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Important
You are viewing documentation for an older version of Confluent Platform. For the latest, click here.
Stream Monitoring
Stream Monitoring provides information about how many messages were produced and consumed over time, highlighting any discrepancies between the two. It also provides statistics about how long it takes for messages to be consumed after production.
Chart Types
There are two chart types - one for visualizing message delivery (expected consumption compared with actual consumption counts) and one for visualizing latency (statistics on the time taken for messages to be consumed after production). These charts are always presented together, with the message delivery chart at the top and latency chart at the bottom.
../../_images/c3deliverylatency.png
Message delivery (top) and latency (bottom) charts.
All times referenced on the charts relate to the time at which messages were sent. More specifically, they are the timestamps included in Kafka messages added at the time messages were produced. By default, these timestamps will be generated by the Kafka Client, but an application may override them. For more information about the use of timestamps, refer to the controlcenter_concept.
All data presented by the charts are binned values. The bin size is uniform across all charts displayed at any given time and is annotated in the message delivery chart legend (in the above chart, the bin size is 15 seconds). The bin size is chosen dynamically to best match the data and display. It depends on time domain of the chart, browser window size and screen resolution.
The delivery chart shows the number of messages expected to be consumed in each time-bin as a step chart and the number of messages actually consumed as an area chart.
Note
Remember that the messages associated with a particular time-bin are those that were produced over the corresponding time range. The time at which messages were consumed never affects which time-bin they are associated with.
A gap between the “expected consumption” line and the “consumed” area indicates that some messages that were produced have not yet been consumed by a consumer group that is reading from the topic. Typically, there will be a gap between expected and actual consumption very close to real time, and this gap will diminish over time. (It takes some time for messages to move through a pipeline to be processed.) If a gap persists past one minute behind real time, Control Center will highlight the gap in orange to help draw your attention to it.
It’s also possible for more messages to be consumed than expected (this can happen in the case of consumer failure). In this case, the area chart will higher than the line chart for the affected time bin and the corresponding area on the chart will also be highlighted orange.
../../_images/c3consumptiondiff.png
Example of both under and over consumption
The latency chart shows the minimum latency, average latency, and maximum latency for messages sent within each time window. See controlcenter_concept for more details about how latency is calculated.
Page Layout
The stream monitoring page is split into two sections. The top section (aggregate view) provides a visualization of a specific subset of all messages and the bottom (detail view) a partitioning of this subset. The available views are:
All messages, grouped by:
1. Consumer group, or
2. Topic
A specific consumer group, grouped by:
1. Consumer, or
2. Topic / partition
A specific consumer, grouped by:
1. Topic / partition
Note
A consumer group may read from more than one topic, so the detail view of a specific consumer group or consumer may be comprised of topic / partitions from more than one topic.
All charts on a given page show information corresponding to an identical time range. Hovering over any chart displays information pertinent to the time bin that the mouse is currently over across all charts. This allows for easy comparison of metrics across all charts.
Time Range and Cluster Selection
The current time range (which pertains to all charts shown on screen at any given time) is displayed inside a button at the top right hand side of the page. Clicking this button will open the time range selector:
../../_images/datepicker.png
The Time Range Selector. Current selection: “October 24, Last 30 minutes”
You can use the selector to select one of three types of time ranges:
1. Static - A specific time range with constant start and end times.
2. Rolling - A time range where the end time always equal to the current time and the extent of the time range is held constant.
3. Growing - A time range where the end time always equal to the current time and the start time is held constant.
Next to the time range selector is the cluster selector which allows you to choose which Kafka Cluster to display data for in a multi-cluster setting. Note that an aggregate view of all messages across all clusters is not available.
Summary statistics
Statistics summarizing the aggregate view data over the current visible time window are displayed near the top right of the screen.
../../_images/c3summarystats.png
Average latency is a weighted average (by consumed count) of the average latency over all visible time bins.
Overall completion is the sum of actual completion over all visible time bins as a percentage of the sum of expected completion over all visible time bins. This number can be greater than 100% in the case of over consumption.
If there is any under-consumption sufficiently behind real time (currently fixed at 1 minute behind real time, rounded up to the nearest bin size) an orange pin will be shown next to the overall consumption value to highlight this.
Note
It’s possible for both the orange pin to be visible and an overall consumption value to be greater than 100%. In this case there would have been both under and over consumption in different time bins, and greater over consumption than under consumption.
Missing Metrics Data
Lost or duplicate messages sent by your application can be seen as a difference between expected and actual consumption values in the message delivery chart.
It’s also possible for messages sent by the Confluent metrics interceptors to be lost or duplicated. If this occurs, the affected time range is highlighted by showing a herringbone pattern on the axis. When interceptor data is lost, we can’t tell if any of your application messages were lost, delayed, or duplicated. (It is possible that they were lost, and also possible that they were not.)
../../_images/errorcloseup.png
Lost stream monitoring metrics
Example Scenarios
In this section, we walk through some typical operational scenarios and discuss how they would show up in Stream Monitoring.
Adding a new Consumer Group
When a new consumer group starts reading messages from one or more topics, new pages will be available in Stream Monitoring corresponding to the new consumer group and it’s constituent consumers. Other aggregates will also start to incorporate information corresponding to the new group where appropriate.
There are a couple of details that warrant further discussion:
1. Latencies associated with the consumption of existing messages.
2. Change of expected consumption in existing aggregates.
Latency
Recall that latency is measured as the difference between the time a message was consumed and the timestamp associated with a message when it was produced.
If a new consumer group is configured to read messages that were produced before it’s creation (often from the first message available on a topic), latencies associated with these early messages could potentially be very high as the messages may have been produced a long time in the past. Also, the latencies will decrease with offset because messages with higher offsets will normally have more recent timestamps.
These factors will result in a descending triangle pattern in the latency charts of consumers in the new consumer group:
../../_images/c3oldmessagelatency.png
Latencies after starting a new consumer group that consumes old messages
The latencies in any aggregate that includes the new consumers (all messages and relevant topic aggregates) will also be impacted. Note that when delivery latencies are very high, they will often dominate latencies in the existing aggregates, producing a decending triangle pattern in these aggregates as well.
Expected consumption
For the different types of aggregation, expected consumption over the duration of a particular time bucket is calculated as follows:
• Consumer - The total number of messages produced onto any topic / partition being read by the consumer over the duration of time bucket.
• Consumer Group - The total number of messages produced onto any topic being read by the consumer group over the duration of time bucket.
• Topic / Partition - The total number of messages produced onto the topic / partition over the durtion of time bucket. Note: this aggregation is always shown on a per consumer basis.
• Topic - The total number of messages produced onto the topic over the duration of the time bucket multiplied by the number of consumer groups that read messages from the topic corresponding to the duration of the time bucket.
• All messages - An aggregate of all Consumer Group aggregates. Also an aggregate of all Topic aggregates. (They are the same thing.)
When a new consumer group is created and starts reading messages from one or more topics, the all messages expected consumption aggregate will be affected, as will any relevant topic expected consumption aggregates.
In the example below, two consumer groups were reading from a particular topic. At about 12:46pm, a new consumer group was started and began reading from the same topic (auto.offset.reset property was set to ‘latest’). Before the new consumer group was started, expected consumption from the topic is 2x the number of messages produced onto the topic. After the new consumer group started, expected consumption is 3x the number of messages produced onto the topic:
../../_images/c3consumergroupstart.png
Change in expected consumption when new consumer started.
In general, the first message read by a consumer will not have a timestamp that aligns with a time bucket window. This causes Control Center to show under-consumption in the first time bucket after the new consumer group starts up because expected consumption is calculated as the total number of messages produced in the time window multiplied by the number of consumer groups that read any message that was produced in the time window.
Note
Control Center cannot differentiate between the scenario described above and an error scenario where there was unexpected under-consumption. For this reason, the under consumption associated with consumer group startup is highlighted in orange, even though it is a normal operational scenario.
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Belajar Laravel : Menginstall Laravel
Assalamualaikum,
Setelah membahas tentang mengapa seharusnya kita belajar laravel, kali ini kita akan bahas bagaimana cara menginstall framework yang satu ini. pertama kawan - kawan harus memenuhi apa yang dibutuhkan oleh Laravel itu sendiri, bisa dibaca di artikel ini.
Oke yang paling penting semua kebutuhan dari Laravel sudah dipenuhi dan juga sudah punya Composer tentunya. Oke cara yang pertama yang bisa kita lakukan untuk menginstall Laravel adalah dengan menggunakan Laravel Installer dengan cara menginstall Laravel Installernya terlebih dahulu dengan menjalankan perintah berikut ini:
composer global require laravel/installer
Pastikan system composer diletakkan di direktori vendor bin di $PATH kamu jadi laravel bisa mengeksekusinya.
• macOS: $HOME/.composer/vendor/bin
• GNU / Linux Distributions: $HOME/.config/composer/vendor/bin
Jika sudah, kita bisa menginstall Laravel dengan perintah:
laravel new nama-aplikasi
Kemudian cara yang kedua kita bisa menggunakan Composer Create Project, cara ini lebih praktis jika kita sudah memiliki Composer di laptop atau komputer kita, kita tinggal jalankan perintah sebagai berikut :
composer create-project laravel/laravel --prefer-dist nama-aplikasi
Begitulah cara menginstall Laravel, semoga bermanfaat.
Wassalamualaikum.
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Skip to main content
Implantando no Azure Kubernetes Service
Você pode fazer deploy de seu projeto no Azure Kubernetes Service (AKS) como parte de fluxos de trabalho para implantação contínua (CD).
Introdução
Este guia explica como usar o GitHub Actions para criar e implantar um projeto no Serviço de Kubernetes do Azure.
Observação: Se os seus fluxos de trabalho de GitHub Actions tiverem de acessar recursos de um provedor de nuvem compatível com o OpenID Connect (OIDC), você poderá configurar seus fluxos de trabalho para efetuar a autenticção diretamente no provedor de nuvem. Isso permitirá que você pare de armazenar essas credenciais como segredos de longa duração e proporcione outros benefícios de segurança. Para obter mais informações, confira "Sobre o enrijecimento de segurança com o OpenID Connect". e "Configurando o OpenID Connect no Azure".
Pré-requisitos
Antes de criar seu fluxo de trabalho de GitHub Actions, primeiro você precisa concluir as etapas de configuração a seguir:
1. Crie um cluster-alvo do AKS e um Azure Container Registry (ACR). Para obter mais informações, confira "Guia de Início Rápido: Implantar um cluster do AKS usando o portal do Azure – Serviço de Kubernetes do Azure" e "Guia de Início Rápido – Criar um registro no portal – Registro de Contêiner do Azure" na documentação do Azure.
2. Crie um segredo chamado AZURE_CREDENTIALS para armazenar suas credenciais do Azure. Para obter mais informações sobre como encontrar essas informações e estruturar o segredo, confira a documentação da ação Azure/login.
Criar o fluxo de trabalho
Depois de preencher os pré-requisitos, você pode prosseguir com a criação do fluxo de trabalho.
O exemplo de fluxo de trabalho a seguir demonstra como criar e implantar um projeto no Azure Kubernetes Services quando o código for enviado por push para o seu repositório.
Abaixo da chave env de fluxo de trabalho, altere os seguintes valores:
• AZURE_CONTAINER_REGISTRY para o nome do registro de contêiner
• PROJECT_NAME para o nome do projeto
• RESOURCE_GROUP para o grupo de recursos que contém o cluster do AKS
• CLUSTER_NAME para o nome do cluster do AKS
Esse fluxo de trabalho usa o mecanismo de renderização helm da ação azure/k8s-bake. Se você usar o mecanismo de renderização helm, altere o valor de CHART_PATH para o caminho para o arquivo do Helm. Altere CHART_OVERRIDE_PATH para uma matriz de caminhos de arquivo de substituição. Se você usar outro mecanismo de renderização, atualize os parâmetros de entrada enviados para a ação azure/k8s-bake.
YAML
# Esse fluxo de trabalho usa ações que não são certificadas pelo GitHub.
# São fornecidas por terceiros e regidas por
# termos de serviço, política de privacidade e suporte separados
# online.
# O GitHub recomenda fixar ações em um SHA de commit.
# Para obter uma versão mais recente, você precisará atualizar o SHA.
# Você também pode fazer referência a uma marca ou branch, mas a ação pode ser alterada sem aviso.
name: Build and deploy to Azure Kubernetes Service
env:
AZURE_CONTAINER_REGISTRY: MY_REGISTRY_NAME # set this to the name of your container registry
PROJECT_NAME: MY_PROJECT_NAME # set this to your project's name
RESOURCE_GROUP: MY_RESOURCE_GROUP # set this to the resource group containing your AKS cluster
CLUSTER_NAME: MY_CLUSTER_NAME # set this to the name of your AKS cluster
REGISTRY_URL: MY_REGISTRY_URL # set this to the URL of your registry
# If you bake using helm:
CHART_PATH: MY_HELM_FILE # set this to the path to your helm file
CHART_OVERRIDE_PATH: MY_OVERRIDE_FILES # set this to an array of override file paths
on: [push]
jobs:
build:
runs-on: ubuntu-latest
steps:
- uses: actions/checkout@v4
- name: Azure Login
uses: azure/login@14a755a4e2fd6dff25794233def4f2cf3f866955
with:
creds: ${{ secrets.AZURE_CREDENTIALS }}
- name: Build image on ACR
uses: azure/CLI@61bb69d64d613b52663984bf12d6bac8fd7b3cc8
with:
azcliversion: 2.29.1
inlineScript: |
az configure --defaults acr=${{ env.AZURE_CONTAINER_REGISTRY }}
az acr build -t -t ${{ env.REGISTRY_URL }}/${{ env.PROJECT_NAME }}:${{ github.sha }}
- name: Gets K8s context
uses: azure/aks-set-context@94ccc775c1997a3fcfbfbce3c459fec87e0ab188
with:
creds: ${{ secrets.AZURE_CREDENTIALS }}
resource-group: ${{ env.RESOURCE_GROUP }}
cluster-name: ${{ env.CLUSTER_NAME }}
id: login
- name: Configure deployment
uses: azure/k8s-bake@61041e8c2f75c1f01186c8f05fb8b24e1fc507d8
with:
renderEngine: 'helm'
helmChart: ${{ env.CHART_PATH }}
overrideFiles: ${{ env.CHART_OVERRIDE_PATH }}
overrides: |
replicas:2
helm-version: 'latest'
id: bake
- name: Deploys application
uses: Azure/k8s-deploy@dd4bbd13a5abd2fc9ca8bdcb8aee152bb718fa78
with:
manifests: ${{ steps.bake.outputs.manifestsBundle }}
images: |
${{ env.AZURE_CONTAINER_REGISTRY }}.azurecr.io/${{ env.PROJECT_NAME }}:${{ github.sha }}
imagepullsecrets: |
${{ env.PROJECT_NAME }}
Recursos adicionais
Os seguintes recursos também podem ser úteis:
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user1532146 user1532146 - 4 months ago 24
Java Question
In Java 8, is it possible to use JVM parameter to control when(or in what condition) to unload class?
In my JMeter test I find that JMeter keep loading classes javascript_gen_cmd__xxx and it makes the test can't reach the throughput I set.
Class loading from JConsole
When I click "Perform GC" button in JVisualVM, the classes are unloaded and the throughput is reached.
So i think it would help if I could indicate when the GC should happen,
for example when the total number of loaded class reach certain number.
I tried -XX:MetaspaceSize=120M but it didn't trigger class unload when the metaspace usage reached 120MB.
Answer
Something like -XX:MaxMetaspaceFreeRatio=30 -XX:MinMetaspaceFreeRatio=10 should cause it to fill up quickly and thus trigger class-unloading GCs.
Alternatively -XX:+ExplicitGCInvokesConcurrent -XX:+ExplicitGCInvokesConcurrentAndUnloadsClasses and using CMS or G1 and firing System.gc() via a timer might work too.
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Available Bandwidth Information
Perhaps the most appealing attribute of MPLS Traffic Engineering is the capability to reserve bandwidth across your network. You configure the amount of reservable bandwidth on a link using the following per-interface command:
router(config-if)#ip rsvp bandwidth [<1-10000000 total-reservable-bandwidth> [per-flow-bandwidth]]
This command can take two parameters. The first is the amount of total reservable bandwidth on the interface, in kbps. The second is the maximum amount of bandwidth that can be reserved per flow on the interface. The per-flow maximum is irrelevant to MPLS Traffic Engineering and is ignored. However, the ip rsvp bandwidth command is used for more than just MPLS Traffic Engineering, and the per-flow-bandwidth parameter has relevance to non-MPLS-related RSVP.
NOTE
Currently, RSVP for MPLS TE and "classic RSVP" (for IP microflows) do not play nicely together. You cannot enable an RSVP pool and have it reserved by both RSVP for MPLS TE and classic RSVP. The heart of the issue is that if you configure ip rsvp bandwidth 100 100, both MPLS TE and classic RSVP (as used for Voice over IP, DLSW+, and so on) each think they have 100 kbps of bandwidth available. This behavior is not a feature. If you're going to use RSVP, use it for MPLS TE or IP
signalling; don't use both in your network at the same time.
If you don't configure the ip rsvp bandwidth command, the default reservable bandwidth advertised for that interface is 0. A common cause of tunnels not coming up during testing or initial deployment of MPLS Traffic Engineering is configuring a TE tunnel to require a certain amount of bandwidth but forgetting to configure available bandwidth on any link. See Chapter 11 for more details on how to detect this.
You don't have to specify a value for the total-reservable-bandwidth value in the ip rsvp bandwidth command. If you don't specify a value, the default is 75 percent of the link bandwidth. The link bandwidth is determined by the interface type or the per-interface bandwidth command.
The per-flow maximum defaults to being equal to the total-reservable-bandwidth parameter, but as previously mentioned, it's irrelevant anyway. So fuggetaboutit.
How much bandwidth do you allocate to the interface? That's a larger question than it might seem at first. It has to do with your oversubscription policies and how you enforce them; see Chapter 10, "MPLS TE Deployment Tips," for more information.
You can double-check your configuration using the command show ip rsvp interface, as demonstrated in Example 3-4.
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What is a hacker?
what is a hacker
When talking about hacker you must think that it is the people who are evil or also called cyber criminals. Actually that's a big mistake about that. Hackers are people who make donations that benefit the computer network, share small programs and share them with the public. But in the literacy, Hackers are people who study, analyze, and furthermore want, can create, modify, or even exploit systems contained in a device such as computer software and computer hardware such as computer programs, administration and other things, especially security.
Contributor:
Yuniar Yuga Wardani
History
Hacker terminology appeared in the early 1960s among members of the Tech Model Railroad Club student organization at the Artificial Intelligence Laboratory of the Massachusetts Institute of Technology (MIT). The group of students is one of the pioneers of computer technology development and they are struggling with a number of mainframe computers. The English word "hacker" first appeared with a positive meaning to refer to a member who has expertise in the field of computers and is able to make computer programs better than those that have been designed together. Then in 1983, the term hackers began to connote negatively. The reason, in that year for the first time the FBI arrested the computer criminal group The 414s based in Milwaukee, United States. 414 is their local area code. The so-called hackers were found guilty of breaches of 60 computers, from computers belonging to the Sloan-Kettering Memorial Cancer Center to computers belonging to the Los Alamos National Laboratory. One of the perpetrators was immunized for his testimonials, while the other five were sentenced to probation.
Then in the next development appears another group who mentions herself as a hacker, but it is not. These (especially adult men) who get satisfaction through breaking into the computer and outsmart the phone (phreaking). True hackers call these people crackers and do not like to associate with them. True hackers look at crackers as lazy, irresponsible, and not very smart. True hackers disagree if it says that by breaking into security someone has become a hacker.
The hackers hold an annual meeting, which is every mid-July in Las Vegas. The world's largest hacker gathering event is called Def Con. Def Con event is more to the event of information exchange and technology related to hacking activities.
Hackers have a negative connotation because of the misunderstanding of the community about the different terms of hackers and crackers. Many people understand that hackers are causing certain party losses such as changing the look of a website (defacing), inserting virus codes, etc., when they are crackers. Cracker is using the security gaps that have not been fixed by software makers (bugs) to infiltrate and destroy a system. For this reason the hackers are usually understood to be divided into two groups: White Hat Hackers, the real hackers and crackers are often called the Black Hat Hackers.
The differences between hacker and cracker
Some people confused to difine between hacker and cracker, so here the differences between them.
Hacker
It is a term for those who make a useful contribution to the world of networks and operating systems. Making internet technology more advanced as hackers use their expertise in computers to see, discover and fix weaknesses of security systems in a computer system or in a piece of software, creating an administrator's resume to work because hackers help administrators to strengthen their networks.
Cracker
It is a term for those who go into other people's systems and crackers are more destructive, usually on computer networks, bypass passwords or computer program licenses, deliberately against computer security, deface (change the webpage) of others even up to Delete other people's data, steal data.
Why do people being hacker?
Computer users have more knowledge in terms of programming and networking have a fundamental reason why they, inging, will, and become a hacker. The reason that should be the initial foundation to become a hacker is the desire to experiment and share information that is closely related to the field of information technology, you who want to follow the footsteps do not feel "inferior" with your current ability, do it consistently and consistently With your skills, join with peers who share the same vision and mission, form a solid group or small community so you and your colleagues can exchange positive information.
How hacker works?
There are various ways by a hacker to find the weakness of a website system so they can hack the website. There are various purposes of a hacker in hacking websites, stealing user information, to just a fad. Here are the various ways and tricks of a hacker to hack a website :
1. Footprinting
2. The initial intelligence on everything related to the intended target. In this way an attacker will obtain a complete security profile / posture from the organization / network that will be attacked.
3. Scanning
4. Scanning is a sign of the start of an attack by a hacker (pre-attack). At this stage, the hacker will look for various possibilities that can be used to take over the computer or system of the target. This stage can be done if the information obtained at the reconnaissance stage is sufficient so that hackers can look for "entrance" to master the system. Tools can help a hacker get through this stage.
5. Enumeration
6. Enumeration is the stage of getting information from the victim as well as the early stages of the hacking process only, you do it in a more active way because it directly targeted your victim. Because you are directly in touch with the victim, this action is very likely recorded by the firewall or IDS so it is considered a fairly dangerous stage for hackers.
7. Gaining access
8. Gaining access can also be said to be a penetration phase, where in this phase hackers exploit the weakness of a known system after performing reconnaissance and scanning activities. Hackers are trying to gain access, for example: hackers are trying to log in to gain administrator privileges when the hacker is not the administrator of the system.
9. Escalating Privilege
10. Escalating Privilege. If you just get a user password ditahap earlier, in this stage get privileged network admin with password cracking or similar exploit get admin, sechole, or lc_messages.
11. Pilfering
12. The information gathering process begins again to identify mechanisms to gain access to a trusted system. Includes trust evaluation and cleartext password search diregiatry, config file, and user data.
13. Covering tracks
14. Once full control of the system is obtained, closing the track becomes a priority. Includes clearing network logs and using hide tools such as rootkits and streaming files.
15. Creating backdoor
16. The rear door is created on various parts of the system to make it easy to re-enter the system by creating a fake user account, scheduling batch jobs, changing startup files, embedding remote control services and monitoring tools, and replacing applications with trojans.
17. Denial Of service
18. If all of the above attempts fail, the attacker may disable the target as a last resort. Includes SYN flood, ICMP techniques, Supernuke, land / latierra, teardrop, bonk, newtear, trincoo, and others.
Hacker Level
It turns out that Hackers also have several levels, you need to know if each level is distinguished between the ability and knowledge they have as a hacker, are :
• Developed kiddie, which has the characteristics of age they are still young (children) and still in school, they tried various systems until finally succeeded and proclaimed victory to their other friend. Usually still using Graph User Interface (GUI) and UNIX Without being able to find new weaknesses in the operating system.
• Lammer, which has experience and knowledge but they want to be a Hacker so lammer is often referred to as "wanna be" Hackers, using their main computer is playing games, exchanging software prirate, IRC, they steal credit cards, they do Hacking by using Software trojan, nuke & DoS, and need buddy know they often brag them.
• Script kiddie, which has characteristics like developed kiddie and also lammer, they only have minimal technical knowledge of networking, And they can not be separated from GUI, hacking is done by trojan to scare and troubles some internet users.
• Elite, which has the characteristics of understanding the internal operating system inside, they are able to confirm and connect the network globally. They are very efficient and skilled because do pemrogramman every day, they use the knowledge properly, do not destroy the data and always follow the existing rules . This elite level is usually called "MASTER".
• Semi elite, which has the characteristics of the elite group, has the ability and extensive insight about computers, they understand the operating system (including kelemahanya), the ability progrannya enough to change the exploit program.
Types of hacking
We can separate the infiltrate into different categories, based on what is being hacked. Here is an example :
• Website hacking
• Hacking a website means taking unauthorized control over the webserver and related software such as databases and other interfaces.
• Network hacking
• Network hacking means collecting information about a network using tools such as Telnet, NS lookup, Ping, Tracert, Netstat, etc. with a view to harming the network system and hampering its operation.
• Email hacking
• Including gaining unauthorized access to the Email account and using it without taking the consent of the owner.
• Ethical hacking
• Ethical hacking involves finding weaknesses in computers or network systems for testing purposes and ultimately keeping them going.
• Password hacking
• This is the secret password recovery process from data stored on or transmitted by computer systems.
• Computer hacking
• This is the process of stealing computer IDs and passwords by applying hacking methods and gaining unauthorized access to computer systems.
Advantages and disadvantages of hacking
Hacking is quite useful in as can be seen below
• To recover lost information, especially in case you forgot your password
• To perform penetration testing to strengthen computer and network security
• To place adequate preventive measures to prevent security breaches
• Have a computer system that prevents malicious hackers gain access
Disadvantages of hacking
Hacking is very dangerous if done with dangerous intent. This can cause :
• Major breach of security
• Unauthorized system access to personal information
• Privacy violation
• Inhibits the operating system
• Service denials attack
• Malicious attacks on the system
Conclusion
Hackers use their computer skills to view, discover and fix security vulnerabilities in a computer system or in software. Therefore, thanks to the hackers that the Internet exists and we can enjoy as now, so hackers can be called a network hero being cracker can be called as a network criminal for doing infiltration with the intention of benefiting himself personallity with the intention of harming others.
References
http://www.kafetechno.com/2016/11/mengenal-istilah-istilah-dalam-dunia-hacking.html
https://books.google.co.id/books?isbn=1452904286
https://books.google.co.id/books?isbn=1446453510
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Part 11: Arrays and Slices
Welcome to the part 11 of Golang tutorial series. In this tutorial we deal with Arrays and Slices in Go.
Arrays
An array is a collection of elements that belong to the same type. For example the collection of integers 5, 8, 9, 79, 76 form an array. Mixing values of different types, for example an array that contains both strings and integers is not allowed in Go.
Declaration
An array belongs to type [n]T. n denotes the number of elements in an array and T represents the type of each element. The number of elements n is also a part of the type(We will discuss this in more detail shortly.)
There are different ways to declare arrays. Lets look at them one by one.
package main
import (
"fmt"
)
func main() {
var a [3]int //int array with length 3
fmt.Println(a)
}
Run in playground
var a [3]int declares a integer array of length 3. All elements in an array are automatically assigned the zero value of the array type. In this case a is an integer array and hence all elements of a are assigned to 0, the zero value of int. Running the above program will output [0 0 0].
The index of an array starts from 0 and ends at length - 1. Lets assign some values to the above array.
package main
import (
"fmt"
)
func main() {
var a [3]int //int array with length 3
a[0] = 12 // array index starts at 0
a[1] = 78
a[2] = 50
fmt.Println(a)
}
Run in playground
a[0] assigns value to the first element of the array. The program will output [12 78 50]
Lets create the same array using the short hand declaration.
package main
import (
"fmt"
)
func main() {
a := [3]int{12, 78, 50} // short hand declaration to create array
fmt.Println(a)
}
Run in playground
The program above will print the same output [12 78 50]
It is not necessary that all elements in an array have to be assigned a value during short hand declaration.
package main
import (
"fmt"
)
func main() {
a := [3]int{12}
fmt.Println(a)
}
Run in playground
In the above program in line no. 8 a := [3]int{12} declares an array of length 3 but is provided with only one value 12. The remaining 2 elements are assigned 0 automatically. The program will output [12 0 0]
You can even ignore the length of the array in the declaration and replace it with ... and let the compiler find the length for you. This is done in the following program.
package main
import (
"fmt"
)
func main() {
a := [...]int{12, 78, 50} // ... makes the compiler determine the length
fmt.Println(a)
}
Run in playground
The size of the array is a part of the type. Hence [5]int and [25]int are distinct types. Because of this, arrays cannot be resized. Don't worry about this restriction since slices exist to overcome this.
package main
func main() {
a := [3]int{5, 78, 8}
var b [5]int
b = a //not possible since [3]int and [5]int are distinct types
}
Run in playground
In line no. 6 of the program above, we are trying to assign a variable of type [3]int to a variable of type [5]int which is not allowed and hence the compiler will throw error main.go:6: cannot use a (type [3]int) as type [5]int in assignment.
Arrays are value types
Arrays in Go are value types and not reference types. This means that when they are assigned to a new variable, a copy of the original array is assigned to the new variable. If changes are made to the new variable, it will not be reflected in the original array.
package main
import "fmt"
func main() {
a := [...]string{"USA", "China", "India", "Germany", "France"}
b := a // a copy of a is assigned to b
b[0] = "Singapore"
fmt.Println("a is ", a)
fmt.Println("b is ", b)
}
Run in playground
In the above program in line no. 7, a copy of a is assigned to b. In line no. 8, the first element of b is changed to Singapore. This will not reflect in the original array a. The program will output,
a is [USA China India Germany France]
b is [Singapore China India Germany France]
Similarly when arrays are passed to functions as parameters, they are passed by value and the original array in unchanged.
package main
import "fmt"
func changeLocal(num [5]int) {
num[0] = 55
fmt.Println("inside function ", num)
}
func main() {
num := [...]int{5, 6, 7, 8, 8}
fmt.Println("before passing to function ", num)
changeLocal(num) //num is passed by value
fmt.Println("after passing to function ", num)
}
Run in playground
In the above program in line no. 13, the array num is actually passed by value to the function changeLocal and hence will not change because of the function call. This program will output,
before passing to function [5 6 7 8 8]
inside function [55 6 7 8 8]
after passing to function [5 6 7 8 8]
Length of an array
The length of the array is found by passing the array as parameter to the len function.
package main
import "fmt"
func main() {
a := [...]float64{67.7, 89.8, 21, 78}
fmt.Println("length of a is",len(a))
}
Run in playground
The output of the above program is length of a is 4
Iterating arrays using range
The for loop can be used to iterate over elements of an array.
package main
import "fmt"
func main() {
a := [...]float64{67.7, 89.8, 21, 78}
for i := 0; i < len(a); i++ { //looping from 0 to the length of the array
fmt.Printf("%d th element of a is %.2f\n", i, a[i])
}
}
Run in playground
The above program uses a for loop to iterate over the elements of the array starting from index 0 to length of the array - 1. This program works and will print,
0 th element of a is 67.70
1 th element of a is 89.80
2 th element of a is 21.00
3 th element of a is 78.00
Go provides a better and concise way to iterate over an array by using the range form of the for loop. range returns both the index and the value at that index. Let's rewrite the above code using range. We will also find the sum of all elements of the array.
package main
import "fmt"
func main() {
a := [...]float64{67.7, 89.8, 21, 78}
sum := float64(0)
for i, v := range a {//range returns both the index and value
fmt.Printf("%d the element of a is %.2f\n", i, v)
sum += v
}
fmt.Println("\nsum of all elements of a",sum)
}
Run in playground
line no. 8 for i, v := range a of the above program is the range form of the for loop. It will return both the index and the value at that index. We print the values and also calculate the sum of all elements of the array a. The output of the program is,
0 the element of a is 67.70
1 the element of a is 89.80
2 the element of a is 21.00
3 the element of a is 78.00
sum of all elements of a 256.5
In case you want only the value and want to ignore the index, you can do this by replacing the index with the _ blank identifier.
for _, v := range a { //ignores index
}
The above for loop ignores the index. Similarly the value can also be ignored.
Multidimensional arrays
The arrays we created so far are all single dimension. It is possible to create multidimensional arrays.
package main
import (
"fmt"
)
func printarray(a [3][2]string) {
for _, v1 := range a {
for _, v2 := range v1 {
fmt.Printf("%s ", v2)
}
fmt.Printf("\n")
}
}
func main() {
a := [3][2]string{
{"lion", "tiger"},
{"cat", "dog"},
{"pigeon", "peacock"}, //this comma is necessary. The compiler will complain if you omit this comma
}
printarray(a)
var b [3][2]string
b[0][0] = "apple"
b[0][1] = "samsung"
b[1][0] = "microsoft"
b[1][1] = "google"
b[2][0] = "AT&T"
b[2][1] = "T-Mobile"
fmt.Printf("\n")
printarray(b)
}
Run in playground
In the above program in line no. 17, a two dimensional string array a has been declared using short hand syntax. The comma at the end of line no. 20 is necessary. This is because of the fact that the lexer automatically inserts semicolons according to simple rules. Please read https://golang.org/doc/effective_go.html#semicolons if you are interested to know more as to why this is needed.
Another 2d array b is declared in line no. 23 and strings are added to it one by one for each index. This is another way of initialising a 2d array.
The printarray function in line no. 7 uses two for range loops to print the contents of 2d arrays. The output of the above program is
lion tiger
cat dog
pigeon peacock
apple samsung
microsoft google
AT&T T-Mobile
Thats it for arrays. Although arrays seem to be flexible enough, they come with the restriction that they are of fixed length. It is not possible to increase the length of an array. This is were slices come into picture. In fact in Go, slices are more common than conventional arrays.
Slices
A slice is a convenient, flexible and powerful wrapper on top of an array. Slices do not own any data on their own. They are the just references to existing arrays.
Creating a slice
A slice with elements of type T is represented by []T
package main
import (
"fmt"
)
func main() {
a := [5]int{76, 77, 78, 79, 80}
var b []int = a[1:4] //creates a slice from a[1] to a[3]
fmt.Println(b)
}
Run in playground
The syntax a[start:end] creates a slice from array a starting from index start to index end - 1. So in line no. 9 of the above program a[1:4] creates a slice representation of the array a starting from indexes 1 through 3. Hence the slice b has values [77 78 79].
Lets look at another way to create a slice.
package main
import (
"fmt"
)
func main() {
c := []int{6, 7, 8} //creates and array and returns a slice reference
fmt.Println(c)
}
Run in playground
In the above program in line no. 9, c := []int{6, 7, 8} creates an array with 3 integers and returns a slice reference which is stored in c.
modifying a slice
A slice does not own any data of its own. It is just a representation of the underlying array. Any modifications done to the slice will be reflected in the underlying array.
package main
import (
"fmt"
)
func main() {
darr := [...]int{57, 89, 90, 82, 100, 78, 67, 69, 59}
dslice := darr[2:5]
fmt.Println("array before",darr)
for i := range dslice {
dslice[i]++
}
fmt.Println("array after",darr)
}
Run in playground
In line number 9 of the above program, we create dslice from indexes 2, 3, 4 of the array. The for loop increments the value in these indexes by one. When we print the array after the for loop, we can see that the changes to the slice are reflected in the array. The output of the program is
array before [57 89 90 82 100 78 67 69 59]
array after [57 89 91 83 101 78 67 69 59]
When a number of slices share the same underlying array, the changes that each one makes will be reflected in the array.
package main
import (
"fmt"
)
func main() {
numa := [3]int{78, 79 ,80}
nums1 := numa[:] //creates a slice which contains all elements of the array
nums2 := numa[:]
fmt.Println("array before change 1",numa)
nums1[0] = 100
fmt.Println("array after modification to slice nums1", numa)
nums2[1] = 101
fmt.Println("array after modification to slice nums2", numa)
}
Run in playground
In line no. 9, in numa[:] the start and end values are missing. The default values for start and end are 0 and len(numa) respectively. Both slices nums1 and nums2 share the same array. The output of the program is
array before change 1 [78 79 80]
array after modification to slice nums1 [100 79 80]
array after modification to slice nums2 [100 101 80]
From the output it's clear that when slices share the same array, the modifications which each one makes are reflected in the array.
length and capacity of a slice
The length of the slice is the number of elements in the slice. The capacity of the slice is the number of elements in the underlying array starting from the index from which the slice is created.
Lets write some code to understand this better.
package main
import (
"fmt"
)
func main() {
fruitarray := [...]string{"apple", "orange", "grape", "mango", "water melon", "pine apple", "chikoo"}
fruitslice := fruitarray[1:3]
fmt.Printf("length of slice %d capacity %d", len(fruitslice), cap(fruitslice)) //length of fruitslice is 2 and capacity is 6
}
Run in playground
In the above program, fruitslice is created from indexes 1 and 2 of the fruitarray. Hence the length of fruitslice is 2.
The length of the fruitarray is 7. fruiteslice is created from index 1 of fruitarray. Hence the capacity of fruitslice is the no of elements in fruitarray starting from index 1 i.e from orange and that value is 6. Hence the capacity of fruitslice is 6. The program outputs length of slice 2 capacity 6.
A slice can be re-sliced upto its capacity. Anything beyond that will cause the program to throw a run time error.
package main
import (
"fmt"
)
func main() {
fruitarray := [...]string{"apple", "orange", "grape", "mango", "water melon", "pine apple", "chikoo"}
fruitslice := fruitarray[1:3]
fmt.Printf("length of slice %d capacity %d\n", len(fruitslice), cap(fruitslice)) //length of is 2 and capacity is 6
fruitslice = fruitslice[:cap(fruitslice)] //re-slicing furitslice till its capacity
fmt.Println("After re-slicing length is",len(fruitslice), "and capacity is",cap(fruitslice))
}
Run in playground
In line no. 11 of the above program,fruitslice is re-sliced to its capacity. The above program outputs,
length of slice 2 capacity 6
After re-slicing length is 6 and capacity is 6
creating a slice using make
func make([]T, len, cap) []T can be used to create a slice by passing the type, length and capacity. The capacity parameter is optional and defaults to the length. The make function creates an array and returns a slice reference to it.
package main
import (
"fmt"
)
func main() {
i := make([]int, 5, 5)
fmt.Println(i)
}
Run in playground
The values are zeroed by default when a slice is created using make. The above program will output [0 0 0 0 0].
Appending to a slice
As we already know arrays are restricted to fixed length and their length cannot be increased. Slices are dynamic and new elements can be appended to the slice using append function. The definition of append function is func append(s []T, x ...T) []T.
x ...T in the function definition means that the function accepts variable number of arguments for the parameter x. These type of functions are called variadic functions.
One question might be bothering you though. If slices are backed by arrays and arrays themselves are of fixed length then how come a slice is of dynamic length. Well what happens under the hoods is, when new elements are appended to the slice, a new array is created. The elements of the existing array are copied to this new array and a new slice reference for this new array is returned. The capacity of the new slice is now twice that of the old slice. Pretty cool right :). The following program will make things clear.
package main
import (
"fmt"
)
func main() {
cars := []string{"Ferrari", "Honda", "Ford"}
fmt.Println("cars:", cars, "has old length", len(cars), "and capacity", cap(cars)) //capacity of cars is 3
cars = append(cars, "Toyota")
fmt.Println("cars:", cars, "has new length", len(cars), "and capacity", cap(cars)) //capacity of cars is doubled to 6
}
Run in playground
In the above program, the capacity of cars is 3 initially. We append a new element to cars in line no. 10 and assign the slice returned by append(cars, "Toyota") to cars again. Now the capacity of cars is doubled and becomes 6. The output of the above program is
cars: [Ferrari Honda Ford] has old length 3 and capacity 3
cars: [Ferrari Honda Ford Toyota] has new length 4 and capacity 6
The zero value of a slice type is nil. A nil slice has length and capacity 0. It is possible to append values to a nil slice using the append function.
package main
import (
"fmt"
)
func main() {
var names []string //zero value of a slice is nil
if names == nil {
fmt.Println("slice is nil going to append")
names = append(names, "John", "Sebastian", "Vinay")
fmt.Println("names contents:",names)
}
}
Run in playground
In the above program names is nil and we have appended 3 strings to names. The output of the program is
slice is nil going to append
names contents: [John Sebastian Vinay]
It is also possible to append one slice to another using the ... operator. You can learn more about this operator in the variadic functions tutorial.
package main
import (
"fmt"
)
func main() {
veggies := []string{"potatoes","tomatoes","brinjal"}
fruits := []string{"oranges","apples"}
food := append(veggies, fruits...)
fmt.Println("food:",food)
}
Run in playground
In line no. 10 of the above program food is created by appending fruits to veggies. Output of the program is food: [potatoes tomatoes brinjal oranges apples]
Passing a slice to a function
Slices can be thought of as being represented internally by a structure type. This is how it looks,
type slice struct {
Length int
Capacity int
ZerothElement *byte
}
A slice contains the length, capacity and a pointer to the zeroth element of the array. When a slice is passed to a function, even though it's passed by value, the pointer variable will refer to the same underlying array. Hence when a slice is passed to a function as parameter, changes made inside the function are visible outside the function too. Lets write a program to check this out.
package main
import (
"fmt"
)
func subtactOne(numbers []int) {
for i := range numbers {
numbers[i] -= 2
}
}
func main() {
nos := []int{8, 7, 6}
fmt.Println("slice before function call", nos)
subtactOne(nos) //function modifies the slice
fmt.Println("slice after function call", nos) //modifications are visible outside
}
Run in playground
The function call in line number 17 of the above program decrements each element of the slice by 2. When the slice is printed after the function call, these changes are visible. If you can recall, this is different from an array where the changes made to an array inside a function are not visible outside the function. Output of the above program is,
slice before function call [8 7 6]
slice after function call [6 5 4]
Multidimensional slices
Similar to arrays, slices can have multiple dimensions.
package main
import (
"fmt"
)
func main() {
pls := [][]string {
{"C", "C++"},
{"JavaScript"},
{"Go", "Rust"},
}
for _, v1 := range pls {
for _, v2 := range v1 {
fmt.Printf("%s ", v2)
}
fmt.Printf("\n")
}
}
Run in playground
The output of the program is,
C C++
JavaScript
Go Rust
Memory Optimisation
Slices hold a reference to the underlying array. As long as the slice is in memory, the array cannot be garbage collected. This might be of concern when it comes to memory management. Lets assume that we have a very large array and we are interested in processing only a small part of it. Henceforth we create a slice from that array and start processing the slice. The important thing to be noted here is that the array will still be in memory since the slice references it.
One way to solve this problem is to use the copy function func copy(dst, src []T) int to make a copy of that slice. This way we can use the new slice and the original array can be garbage collected.
package main
import (
"fmt"
)
func countries() []string {
countries := []string{"USA", "Singapore", "Germany", "India", "Australia"}
neededCountries := countries[:len(countries)-2]
countriesCpy := make([]string, len(neededCountries))
copy(countriesCpy, neededCountries) //copies neededCountries to countriesCpy
return countriesCpy
}
func main() {
countriesNeeded := countries()
fmt.Println(countriesNeeded)
}
Run in playground
In line no. 9 of the above program, neededCountries := countries[:len(countries)-2] creates a slice of countries barring the last 2 elements. Line no. 11 of the above program copies neededCountries to countriesCpy and also returns it from the function in the next line. Now countries array can be garbage collected since neededCountries is no longer referenced.
I have compiled all the concepts we discussed so far into a single program. You can download it from github.
Thats it for arrays and slices. Thanks for reading. Please leave your valuable feedback and comments.
Next tutorial - Variadic Functions
Naveen Ramanathan
Naveen Ramanathan has more than 11 years of programming experience in backend and mobile app development. If you would like to hire him, please mail to naveen[at]golangbot[dot]com
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Salta al contenuto principale
Set completo di informazioni sulla riparazione di sistemi e accessori Sony PlayStation. Cominciando con il rilascio della PlayStation originale nel dicembre 1994, Sony ha continuato a sviluppare la PlayStation e diverse versioni della PlayStation Portable (PSP).
5261 Domande Visualizza tutte
PS3: extremely noisy fan
As soon as the console starts up the fan is blowing hard.
The noise is not scratchy or anything but the fan spins at full speed. The console does not seem to be that hot to justify such a blowing.
Can anybody help?
Thank you
Armando
Risposto! Visualizza la risposta Anch'io ho questo problema
Questa è una buona domanda?
Punteggio 7
Commenti:
Armando which PS3 do you have? Does it have enough airflow? Are the airvents clear of any obstruction? How hot is the room where your PS3 is located? Do you have it on the floor or in a cabinet?
da
It's the standard PS3 (not the slim version). Airvents are clear, the room is not particularly hot, even in this summer days the room is somewhere in the neighbor of 24-25°C, and the console is on the floor in a vertical position.
da
I'm sure there is guide on here for how to keep your console (xbox/ps3) in best ventilation and maintenance to prevent ylod etc which might be of use..i think it mentions not vertical?
da
I think the 40 GB has a "Fan Test" feature. Switch off console on front, so red lights appear. Place your finger on eject button (keep it held on), switch it off at the bak with your finger still on eject button, then switch it back on. I believe that this will run the fan at its highest speed to "blow out" any debris. you might want to give it a try.
da
It could be that the thermal paste on the heat sink has dried out and it needs to be applied again . I had a computer that was doing that so I took the heat sink off off the CPU on the motherboard and reapplied the thermal past now it's very quiet. Since consoles these days are like computers that could be it
da
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8 Risposte
Soluzione Prescelta
slim guide:PlayStation 3 Slim Fan Replacement
normal guide:Sostituzione ventola PlayStation 3
slimline guide:not available
normal(ps2)guideSostituzione ventola PlayStation 2:
Immagine PlayStation 2 Ventola
Guida
Sostituzione ventola PlayStation 2
Difficoltà:
Moderato
40 minutes - 1 hour
Immagine PlayStation 3 Slim Fan
Guida
PlayStation 3 Slim Fan Replacement
Difficoltà:
Moderato
15 - 30 minutes
Immagine PlayStation 3 Ventola
Guida
Sostituzione ventola PlayStation 3
Difficoltà:
Moderato
30 minutes - 1 hour
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Commenti:
the problem is the fan doesn't like the changes of the console and will blow hard for for a warning and/or the fan may not be properly seated,so these guides are the solution (sorry there's no ps2 slimline fan installation guide)
da
It is now clarified that the device in question is a PS3 non-slim version. So you can clean your answer by deleted the unnecessary links.
da
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Risposta Più Utile
The ps3 fan has 3 fan speeds (factory standards)
In summer its humid hot etc the air blowing out might not be HOT but the components inside are so this is what its cooling down!
You can notice the fan is louder when it goes at full speed but this is normal
3RD party fans DO NOTHING IN THE SLIGHTEST!
Get AIR CON
Or get a small fan blowing air onto the console. And make sure it isn't clogged up with dust.
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Sit your PS3 up on something to let the bottom ventilate. Instead of standing it up, lay it down and prop it up on a couple of tuna cans or something...anything to get it up off a surface. That should help quiet it down some.
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Take it apart and clean it with air compressor. I just cleaned mine due to loud fan, now it's quiet as can be!
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Hi, can you give me idea of what you mean when taking apart and cleaning system? Also, what compressed air do you use on it?
da
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Usually it sounds loud because it is overheating dust is clogging it so the fans are to cool them I recommend that put some cool air conditionar near it and put it above the floor with something soft.
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I encountered the somewhat same problem with my ps3 only after 10 to 20 minutes of operating time the fan would go into high blow mode sounding like a jet engine. Proceeded to feel the air at the back of console and the temperature was very warm. I then unplugged all cords and used compressed air from my air compressor with 2/16 inch rubber nozzle on air gun and began flushing all dust from every angle and every open port including taking off the sanp hard drive door also. Continued flushing with compressed air for about 10 to 15 minutes until no more dust debris came out. Plugged all cords in and turned on waited for the fan to kick into high and didn't also temperature of air coming from the back of console seemed alot cooler also. Sidenote using compressed air in can might damage componets by coating essential components with frozen nitrogen hindering porcesses and doing permanent damage.
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Commenti:
I just used your Technic and it worked so %#*@ good that I didn't know my shyt came on! Quiet as a Mutha!
Thank you
da
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Honestly a major factor in fan noise is the position of the console to the surrounding material. So if the PS3 case touches a solid surface, it will sound much louder. If the PS3 is near a wall or solid surface, it will reflect sound waves more efficiently and make your PS3 fan much louder!
You can dampen the noise by moving it away from solid surface and raising the console a few inches on something soft (paperback).
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After reading all the posts and knowing that my fan is not faulty it's just running full speed, I realized I have never blown the dust out of it. I turned it on and my fan ran for a few seconds and immediately goes full speed for about 3 seconds and then calms down. I unplugged it took it down to the shop and blew it out with my air compressor at all different angles in every whole back and forth and even when one side seemed clean I blew the other side out and realized it was blowing dust back and forth inside you must go back and forth between all of the ports many times until no dust comes out. If your fan is not faulty it is obviously a heat problem especially on systems like mine which is the 80 gig first generation with almost full backwards compatibility with PS1 and 2. This unit was the first of its kind and I had to special-order it. The later units had the backwards compatibility removed and some processor load reduced in order to lower power consumption. This is very common on the first generation. I would not suggest taking your PS3 apart if you ever plan to have it fixed by Sony they will not touch it even if you pay them. No one has ever opened my system except Sony for a hard drive replacement many years ago. I agree not to use canned air because if any liquid comes out of the can if it does not damage the board it could cause the heat sink paste to become brittle and not conduct heat away from the processor and the fan will always run fast. Blowing the unit out has made a huge Improvement but be careful and do not blow air near the disk slot or you can get dust on the laser and your Blu-ray will not work correctly and don't hold the air hose directly on the vent holes give it 5 or 6 inches in case there is some water condensation in your airline I suggest using an airline with a dryer on it. This has fixed my problem. I have done some temperature test and this unit does run cooler if laid flat because then there are no vents on the bottom. This unit is going to be louder than the later version because it is a power monster. Also suggest you hang on to this unit they are getting rare if you have one like mine with the door and all the slots and 80 gig hard drive and full backwards compatibility. I was offered more for mine than I paid for it which is very rare for a game console so take care of it. Hope this helps.
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take your system completly apart, wipe off the crusty thermal paste on the apu and slop new thermal grease all over the top then put it back together as best you can. left over screws are normal just throw them out
da
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Armando sarà eternamente grato.
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Midpoint Calculator
An online calculator to calculate the midpoint of a segment defined by two points A(Xa , Ya) and B(Xb,Yb). The midpoint is a point whose x and y coordinates are given by
x coordinate = (Xa+Xb) / 2
y coordinate = (Ya+Yb) / 2
How to use the calculator
1 - Enter the x and y coordinates of points A and B and press enter.
Point A: ( , )
Point B: ( , )
More Math Calculators and Solvers.
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/* * Copyright (c) 2000 Silicon Graphics, Inc. All Rights Reserved. * * This program is free software; you can redistribute it and/or modify it * under the terms of version 2 of the GNU General Public License as * published by the Free Software Foundation. * * This program is distributed in the hope that it would be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. * * Further, this software is distributed without any warranty that it is * free of the rightful claim of any third person regarding infringement * or the like. Any license provided herein, whether implied or * otherwise, applies only to this software file. Patent licenses, if * any, provided herein do not apply to combinations of this program with * other software, or any other product whatsoever. * * You should have received a copy of the GNU General Public License along * with this program; if not, write the Free Software Foundation, Inc., 59 * Temple Place - Suite 330, Boston MA 02111-1307, USA. * * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy, * Mountain View, CA 94043, or: * * http://www.sgi.com * * For further information regarding this notice, see: * * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/ */ #include #include void expect_error(int r, int err) { if (r<0) { if (errno == err) { printf(" --- got error %d as expected\n", err); } else { perror(" !!! unexpected error"); } } else { printf(" !!! success instead of error %d as expected\n", err); } } int main(int argc, char **argv) { int fsfd; if (argc != 2) { fprintf(stderr,"usage: %s \n", argv[0]); exit(0); } fsfd = open(argv[1], O_RDONLY); if (fsfd < 0) { perror("open"); exit(1); } printf("--- ioctl with bad output address\n"); expect_error(ioctl(fsfd, XFS_IOC_FSCOUNTS, NULL), EFAULT); printf("--- ioctl with bad input address\n"); expect_error(ioctl(fsfd, XFS_IOC_SET_RESBLKS, NULL), EFAULT); close(fsfd); return 0; }
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Câu hỏi của Nguyễn Thị Kim Anh - Toán lớp 7 - Học trực tuyến OLM
Lỗi: Trang web OLM.VN không tải hết được tài nguyên, xem cách sửa tại đây.
Hỏi đáp bài tập
Gọi số cần tìm là \(\overline{ab7}\)và số mới là \(\overline{7ab}\), ta có:
\(\overline{7ab}\div\overline{ab7}=2\)dư 21
\(\Rightarrow\left(\overline{7ab}-21\right)\div\overline{ab7}=2\)
Mà \(2\times\overline{ab7}=\)số có tận cùng là 4 hay tận cùng là ( b - 1 ) của \(\left(\overline{7ab}-21\right)\)
\(\Leftrightarrow b-1=4\)
\(\Rightarrow b=5\)
Ta lại có :
\(\left(\overline{7ab}-21\right)=\overline{6xy}\)hoặc \(\overline{7cd}\)chia 2 bằng \(\overline{3zt}\)bằng \(\overline{a47}\)( x, y, c, d, z, t là số tự nhiên )
\(\Rightarrow a=3\)
Vậy ta có số cần tìm là 357
Đọc tiếp...
mk k hiểu chỗ :
7ab - 21 = 6xy hoặc 7cd chia 2 bằng 3zt bằng a47 (...)
=> a = 3 ????
GIải thik hộ mk nhé ! mk cảm ơn !!!!
Đọc tiếp...
Dưới đây là một vài câu hỏi có thể liên quan tới câu hỏi mà bạn gửi lên. Có thể trong đó có câu trả lời mà bạn cần!
Gọi số cần tìm là ab7
Nếu chuyển 7 lên đầu ta được số 7ab.
Ta có:
\(7ab=2.ab7+21\)
\(\Rightarrow700+ab=2.\left(ab.10+7\right)+21\)
\(=20.ab+14+21=20.ab+35\)
\(\Rightarrow700=19.ab+35\)
\(\Rightarrow19.ab=665\)
\(\Rightarrow ab=35\)
\(\Rightarrow ab7=357\)
Vậy số cần tìm là 357.
Đọc tiếp...
Số cần tìm là (ab7) = 100a + 10b + 7
Số mới là (7ab) = 700 + 10a + b
Ta có 700 + 10a + b = 2(100a + 10b + 7) + 21
<=> 10a + b + 700 = 200a + 20b + 35
<=> 190a + 19b = 665 <=> 10a + b = 35 <=> a = 3; b = 5
---> Số cần tìm là 357.
quá dễ
động não đi
Đọc tiếp...
Tài trợ
sin cos tan cot sinh cosh tanh
Phép toán
+ - ÷ × = ∄ ± ⋮̸
α β γ η θ λ Δ δ ϵ ξ ϕ φ Φ μ Ω ω χ σ ρ π ( ) [ ] | /
Công thức:
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FIND and SEARCH Function in Excel (2 Comparison Studies)
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It is a very common occurrence to find the position of a particular character or text within a string. This is helpful for data analysis purposes such as extracting, text parsing, etc. Both FIND and SEARCH functions can be used for this purpose. However, in some cases, one can be more suitable than the other. This article will cover an in-depth analysis of the FIND and SEARCH function in Excel, their similarities and differences.
find and search function in excel
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You can download the workbook used for the demonstration from the link below.
Introduction to Excel FIND Function
In Microsoft Excel, the FIND function is generally used to extract the position of a defined text in a cell containing a text string.
• Syntax
FIND(find_text, within_text, [start_num])
• Arguments
find_text is a text or a part of a text to be searched for in a cell containing another text string.
within_text is the cell containing the text where the function will search the defined character or part of the text.
[start_num] is an optional argument which is a defined position in the text string from where the character count will initiate. The default value is 1.
Introduction to Excel SEARCH Function
The SEARCH function returns the number of characters after finding a specific character or text string, reading from left to right. This function searches for a case-insensitive match. It works for both array and non-array formulas.
• Syntax
SEARCH(find_text,within_text,[start_num])
• Arguments
find_text is the text that we search for. It can be a single text or an array of texts.
within_text is the value within which the function searches for the find_text argument. It can be a single text value or an array of text values.
[start_num] is an optional argument like the one used in the FIND function. It is the position of the within_text argument from which it starts searching. It can be a single number or an array of numbers. The default value is 1.
FIND and SEARCH Function in Excel: 2 Comparison Studies
As we can see from the previous sections, both the FIND and SEARCH functions serve the same purpose. They have the same arguments, even the default optional one. However, there can be different results in some cases. This section will cover the different outcomes and their cause for the functions.
1. FIND and SEARCH Function Application for Case Sensitive Searches
This is the main difference between the FIND and SEARCH functions in Excel.
The FIND function searches for the string provided in the find_text argument as it is. If the string of this argument is in upper case, the function will try to find the uppercase match and vice versa. Meanwhile, the SEARCH function just tries to find the string however it is suitable irrespective of whether the letters are capital or small.
Let’s take the following dataset for the demonstration. The dataset contains the text “I am The king of the world”. There are two “the”s in the string. One has an uppercase “T” at the start.
text for case sensitive searches
• Insert the following formula in cell C7. You will see the position of the string “the” is 18.
=FIND(C7,B5)
find function for lower case
• If we insert the following formula instead, we will see the position of the string is 6.
=FIND(D7,B5)
find function for upper case
• For the SEARCH function, insert the following formula. The position of the string here is 6.
=SEARCH(C7,B5)
search function for lower case
• If we insert the following formula for capitalized letters, we can see that the function, once again, gives the result 6.
=SEARCH(D7,B5)
search function for upper case
As we can see, when we search for the string “the”, the FIND function will give us the value of the one with the lowercase letter. This is the starting position of “the” before the “world”.
While searching for “The” with the FIND function it gives 6 which is the starting position of “The” before the “king”.
Irrespective of “the” or “The” we put inside to find with the SEARCH function, we get 6. Because this always targets the one before the ‘king” and is the first match.
Read More: How to Find Text in Cell in Excel
2. FIND and SEARCH Function with Wildcard Arguments
Another major difference between the FIND and SEARCH functions in Excel is the ability to search with wildcard arguments.
As we have seen in the previous section, the FIND function searches for the exact match including the exact case used. So, it can not search for wildcard characters. Meanwhile, the SEARCH function does not look for exact matches and thus we can use wildcards there.
Let’s take the following dataset. It contains some sentences informing about book publishing years. We are going to search if the years in the 20th century are available in the dataset.
wildcard argument texts
The search string we are going for is “19**”. It searches for any string that starts with 19 and will give us the position where 1 starts here if there is a match in the string. Let’s see how it interacts with FIND and SEARCH functions in Excel.
• Inserting the following formula in cell G5 and filling it in G7 gives us an error.
=FIND("19**",B5)
find function result for wildcard arguments
• If we use the following formula for the range H5:H7, we will get some results.
=SEARCH("19**",B5)
search function result for wildcard arguments
Although there are some matches in the first and second strings, the FIND function will always result in a #VALUE error. However, the SEARCH function can pick up the values and returns the position where it found the match. Only the third one gives an error because the year specified in cell D7 does not meet the criteria.
This is another thing to consider while distinguishing between FIND and SEARCH functions while searching for string positions.
FIND and SEARCH Function in Excel: 4 Similar Uses
Aside from the two cases we have discussed, we can use FIND and SEARCH functions in Excel interchangeably. In this section, we will discuss some similarities and how both functions pretty much give the same result in most cases.
1. Combining with LEFT and RIGHT Functions to Find String Before and After Character
Let’s take the following dataset which contains a list of full names of some people. Suppose, we want to extract the first names and last names from the list.
dataset to split names
The idea of extracting a portion of the string is to use the LEFT function and extracting some from the end requires the RIGHT function. These functions require some positional arguments of how many characters they will extract. This is where the FIND and SEARCH functions come into play. We are going to use the LEN function too, which gives the length of the string it takes as an argument.
• Insert the formula in cell C6 and drag the fill handle down to C10.
=LEFT(B6, FIND(" ", B6)-1)
finding first name with left and find functions
🔎 Formula Breakdown
• FIND(” “, B6) searches for an empty string in the value of cell B6. In this case, it returns 6.
• LEFT(B6, FIND(” “, B6)-1) then extracts the first 5 characters from the left of the string. This is the word that comes before the empty space and thus the first name. 1 was extracted in the formula as it would take the space too otherwise.
• Now fill the range D6:D10 with the following formula.
=RIGHT(B6,LEN(B6)-FIND(" ",B6))
finding last name with right and find functions
🔎 Formula Breakdown
• LEN(B6) returns the length of the character in cell B6. In this case, it is 12.
• FIND(“ ”,B6) searches for the first empty string in cell B6, which is 6.
• LEN(B6)-FIND(” “,B6) gives the number of characters after the space in the string. In this case, it is 6.
• RIGHT(B6,LEN(B6)-FIND(” “,B6)) extracts the final 6 characters from the string and gives us the last name.
• Now insert the value in cell E6 and replicate it to E10.
=LEFT(B6, SEARCH(" ", B6)-1)
finding first name with left and search functions
🔎 Formula Breakdown
• SEARCH(” “, B6) searches for the space in cell B6, which is 6 in this case.
• LEFT(B6, SEARCH(” “, B6)-1) returns a number less than the previous function returns as we don’t want the space to include it in the first name.
• Using the following formula for the range F6:F10 will result as follows.
=RIGHT(B6,LEN(B6)-SEARCH(" ",B6))
finding last name with right and search functions
🔎 Formula Breakdown
• LEN(B6) returns the length of the characters in cell B6.
• SEARCH(” “,B6) searches for an empty string in cell B6 and returns the first one it finds from left to right.
• LEN(B6)-SEARCH(” “,B6) indicates the characters available after the space in cell B6.
• RIGHT(B6,LEN(B6)-SEARCH(” “,B6)) then extracts the characters from the right of the string which is the last name from cell B6.
As we can see from four different formulas from the full list of names, there are no differences in the results. The reason behind this is there is no case difference while searching for an empty string. So we can use FIND and SEARCH functions interchangeably in these cases.
Read More: How to Find a Character in String in Excel
2. Merging with MID Function to Find String Between Parentheses
Like space as the string argument, we can both FIND and SEARCH functions for parenthesis too. Take the following dataset containing different product IDs.
finding text between parantheses
We are going to extract values that are inside the brackets. We can use the LEFT and RIGHT functions like the previous example here too. But, we are going to use the MID function here to show the similarity of the FIND and SEARCH functions.
• Select cell C6, insert the following formula and replicate it to the end of the column.
=MID(B6,FIND("(",B6)+1, FIND(")",B6)-FIND("(",B6)-1)
finding text between parentheses with find function
🔎 Formula Breakdown
• FIND(“(“,B6) searches for the position of the opening parenthesis in cell B6, which is 4 here.
• FIND(“)”,B6) searches for the closing parenthesis which is at the 10th position. So it returns 10.
• FIND(“)”,B6)-FIND(“(“,B6)-1 is one less than the difference between closing and opening brackets. The significance of it is it indicates the number of characters in between the brackets. In this case, it is 5.
• MID(B6,FIND(“(“,B6)+1, FIND(“)”,B6)-FIND(“(“,B6)-1) extracts 5 characters from the string, starting from the 5th position(+1 in the starting argument). In the end, we get what is between the brackets in this way.
• To do the same with the SEARCH function, insert the following formula in cell D6 and replicate it till the end of the column.
=MID(B6,SEARCH("(",B6)+1, SEARCH(")",B6)-SEARCH("(",B6)-1)
finding text between parentheses with search function
🔎 Formula Breakdown
• SEARCH(“(“,B6) searches for the opening parenthesis of the value of cell B6 which is 4 in this case.
• SEARCH(“)”,B6) searches for the closing bracket in the value of cell B6 which is 10.
• SEARCH(“)”,B6)-SEARCH(“(“,B6)-1 is one less than that of the position of closing and opening brackets. The -1 at the end is there because the simple difference would include the closing bracket too.
• MID(B6,SEARCH(“(“,B6)+1, SEARCH(“)”,B6)-SEARCH(“(“,B6)-1) then extracts all the characters starting from the 5th position to the 9th which is the string inside the parentheses.
As we can see the outputs are the same in both of the cases. This is because there are no case differences in the opening or closing brackets. There is no wildcard usage here either. So, no matter the function we are combining it with, it gives the same result.
Read More: How to Find Character in String Excel (8 Easy Ways)
3. FIND and SEARCH Function to Find Nth Occurrence of Character
We can do the same for all the special characters and lowercase alphabetic characters. In this section, we will discuss the usage of FIND and SEARCH function in Excel. Much like the previous examples, it should end up with the same result too unless at least an uppercase value is involved.
We are going to operate with the following dataset for this example. The dataset contains a set of strings with a hyphen (-) between them. We are going to find the position of the 3rd hyphen in the string with both the FIND and SEARCH functions.
finding nth occurrence of a character dataset
• First, enter the following formula in cell C6 and copy it down to cell C9.
=FIND("-",B6, FIND("-", B6, FIND("-",B6)+1) +2)
finding nth occurrence with find function
🔎 Formula Breakdown
• FIND(“-“,B6) searches for a hyphen in the string of cell B6, which it finds at the third position.
• FIND(“-“, B6, FIND(“-“,B6)+1) Here the third argument is the optional argument that indicates the main FIND function to start the search from here. FIND(“-“,B6) actually is the first hyphen as mentioned earlier. So using it alone gives the second hyphen position.
• Now using the previous formula as the argument of the main function, it will start the search from the second hyphen. As a result, the final output will be the position of the third hyphen.
• Then in cell D6, we are going to use the following formula.
=SEARCH("-",B6, SEARCH("-", B6, SEARCH("-",B6)+1) +2)
finding nth occurrence with search function
🔎 Formula Breakdown
• SEARCH(“-“,B6) searches for the hyphen in the string of cell B6, which it finds at the third position.
• SEARCH(“-“, B6, SEARCH(“-“,B6)+1) The third argument is the optional argument that indicates the main SEARCH function to start the search from here. SEARCH(“-“,B6) actually is the first hyphen as mentioned earlier. So using it alone gives the second hyphen position.
• Now using the previous formula as the argument of the main function, it will start the search from the second hyphen. As a result, the final output will be the position of the third hyphen.
Even looping the FIND and SEARCH function with themselves give the same output as long as the string it search for is the same and case insensitive.
Read More: Excel Search for Text in Range (11 Quick Methods)
Similar Readings
4. Error Handling with FIND and SEARCH Function in Excel
The FIND and SEARCH function returns an error while not encountering the values they search for. We can combine them with the IFERROR function. This will allow the spreadsheet to not show the error values. Instead, it will give us the output we want in those cases.
As long as the arguments are case insensitive and wildcards are not used, the function will give us the same values.
The following dataset contains some quotes in column B. We are going to search where “great”s are inside these quotes.
error handling dataset
• For the range C6:C10, we are going to use the following formula to replicate.
=IFERROR(FIND("great",B6), "value not found!")
combining iferror and find functions
🔎 Formula Breakdown
• FIND(“great”,B6) searches for the string “great” in cell B6 and returns the position of “g” in the first match from left to right.
• If there are no matches of the string in the desired cell, IFERROR(FIND(“great”,B6), “value not found!”) returns another string “value not found!”
• In the range D6:D10, we are going to use the following formula.
=IFERROR(SEARCH("great",B6), "value not found!")
combining iferror and serach functions
🔎 Formula Breakdown
• SEARCH(“great”,B6) searches for the string “great” in cell B6. It also returns the first position of the character the first place it finds the match from left to right.
• IFERROR(SEARCH(“great”,B6), “value not found!”) returns another string “value not found!” if the SEARCH function doesn’t find any match for the value.
Notice that we have used a case-sensitive search here. The quote in cell B9 is an uppercase “Great”. So, the FIND function encounters an error here and gives a different result than the SEARCH function. Other values are the same. Because if the string “great” exists in them they are in the lower case.
So, as long as the upper/lower case in the string is not of concern, the FIND and SEARCH function gives the same output no matter how we use them.
Read More: How to Use Formula to Find Bold Text in Excel
Causes of #VALUE! Error in FIND and SEARCH Function in Excel
We have already seen a #VALUE! error in the wildcard example. It happened there because the FIND function couldn’t find an exact match in the string. There are other causes of the #VALUE! Error for FIND and SEARCH function in Excel.
• If there are any invalid arguments in the functions such as number or text values, it results in a #VALUE!
• When the string which we are searching the particular string from, or the second argument is not Excel’s text type value, it causes the error.
• The circular references where the result of the function depends on its own result, the function gives us the #VALUE!
• If you use any array arguments and do not press Ctrl+Shift+Enter, it may cause the #VALUE!.
Frequently Asked Questions
• How do I search for Find and Select in Excel?
You can press Ctrl+G on your keyboard for the shortcut to launch the Find and Select feature. Or, you can find that in Home > Find & Select (available in the Editing group) > Go to.
• How do I find and select all values in Excel?
To select all cells with values in a dataset, select a cell within it and press Ctrl+A on your keyboard. If you select a blank cell instead, it will select all of the cells in the spreadsheet.
• How do I search and extract text in Excel?
You can extract text from a string using a combination of LEFT, RIGHT, MID, LEN, etc functions along with FIND or SEARCH functions. A little bit of it is shown in the similar uses section. For more details, you can check out this article- how to extract text from a cell in Excel.
Things to Remember
• Both functions use the same set of arguments- a string to look for, where it will look, and the starting point from where it will search.
• If you need to perform a case-sensitive search, use the FIND Otherwise, you use the SEARCH function.
• For wildcard uses definitely use the SEARCH function.
• For non-alphabetic character searches, you can search with either of the functions.
• Be sure to use the third argument in cases where you need to skip some of the first matches.
• Both functions only work with text values.
Conclusion
That concludes the discussion of similarities and differences between the FIND and SEARCH function in Excel. The main thing to keep in mind for everyday usage is case sensitivity, even while combining with other functions. Hopefully, you can use both functions to find string positions and apply them to your formulas with ease now. I hope you found this guide helpful and informative. If you have any questions or suggestions, let us know in the comments below.
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Sabrina Ayon
Sabrina Ayon
Hi there! This is Sabrina Ayon. I'm really excited to welcome you to my profile. Currently, I'm working in SOFTEKO as a Team Leader. I'm a graduate in BSc in Computer Science and Engineering from United International University. I love working with computers and solving problems. I’ve always been interested in research and development. Here I post articles related to Microsoft Excel. Hoped this may help you. Thank you.
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Jaylen Jaylen - 8 months ago 32
jQuery Question
TypeError: children.size is not a function with jQuery
I found a small plugin that will allow me to add simple pages to my html table.
The first thing I did was to create a new js file and added the following code to it.
(function ($) {
$.fn.SimplePages = function (opts) {
var self = this;
var defaults = {
perPage: 10,
showPrevNext: false,
hidePageNumbers: false
};
var settings = $.extend(defaults, opts);
var listElement = self;
var perPage = settings.perPage;
var children = listElement.children();
var pager = $('.pager');
if (typeof settings.childSelector != "undefined") {
children = listElement.find(settings.childSelector);
}
if (typeof settings.pagerSelector != "undefined") {
pager = $(settings.pagerSelector);
}
var numItems = children.size();
var numPages = Math.ceil(numItems / perPage);
pager.data("curr", 0);
if (settings.showPrevNext) {
$('<li><a href="#" class="prev_link">«</a></li>').appendTo(pager);
}
var curr = 0;
while (numPages > curr && (settings.hidePageNumbers == false)) {
$('<li><a href="#" class="page_link">' + (curr + 1) + '</a></li>').appendTo(pager);
curr++;
}
if (settings.showPrevNext) {
$('<li><a href="#" class="next_link">»</a></li>').appendTo(pager);
}
pager.find('.page_link:first').addClass('active');
pager.find('.prev_link').hide();
if (numPages <= 1) {
pager.find('.next_link').hide();
}
pager.children().eq(1).addClass("active");
children.hide();
children.slice(0, perPage).show();
pager.find('li .page_link').click(function () {
var clickedPage = $(this).html().valueOf() - 1;
goTo(clickedPage, perPage);
return false;
});
pager.find('li .prev_link').click(function () {
previous();
return false;
});
pager.find('li .next_link').click(function () {
next();
return false;
});
function previous() {
var goToPage = parseInt(pager.data("curr")) - 1;
goTo(goToPage);
}
function next() {
goToPage = parseInt(pager.data("curr")) + 1;
goTo(goToPage);
}
function goTo(page) {
var startAt = page * perPage,
endOn = startAt + perPage;
children.css('display', 'none').slice(startAt, endOn).show();
if (page >= 1) {
pager.find('.prev_link').show();
}
else {
pager.find('.prev_link').hide();
}
if (page < (numPages - 1)) {
pager.find('.next_link').show();
}
else {
pager.find('.next_link').hide();
}
pager.data("curr", page);
pager.children().removeClass("active");
pager.children().eq(page + 1).addClass("active");
}
};
}( jQuery ));
Then I am trying to use this plugin like so
$(function () {
$('#UserToClientRelationTable').SimplePages(
{
pagerSelector: '#UserToClientRelationTablePager',
showPrevNext: true,
hidePageNumbers: false,
perPage: 5
});
});
Unfortunately this code keeps giving me the following error in the console
TypeError: children.size is not a function
And, yes I loaded jQuery before loading this file. In face, if I remove this code and the pagination the rest of my code give me no errors.
How can I fix this problem?
Answer
size() was deprecated a long time ago and completely removed from jQuery 3
The norm is to use length property instead
See size() docs
if you are using a version less than 3, then problem is likely elsewhere and we need more info
|
__label__pos
| 0.997629 |
Move semantics is the C++11 feature that allows a copy operation to be replaced by a more efficient "move" when the source object is an rvalue (typically a temporary)
learn more… | top users | synonyms
13
votes
2answers
399 views
Should the Copy-and-Swap Idiom become the Copy-and-Move Idiom in C++11?
As explained in this answer, the copy-and-swap idiom is implemented as follows: class MyClass { private: BigClass data; UnmovableClass *dataPtr; public: MyClass() : data(), ...
14
votes
4answers
543 views
Is std::move really needed on initialization list of constructor for heavy members passed by value?
Recently I read an example from cppreference.../vector/emplace_back: struct President { std::string name; std::string country; int year; President(std::string p_name, std::string ...
1
vote
2answers
93 views
When should I supply a move-aware overload?
If I have a class that manages some dynamic memory (e.g. a vector-type class) and it already has a move-constructor, does it ever make sense to supply a move-aware overload for a function, or will the ...
6
votes
1answer
182 views
Why move on const objects work?
I have a simple code : const std::vector<int> data = {1,2,3}; std::vector<int> data_moved=std::move(data); for(auto& i:data) cout<<i;//output is 123 It compiles without ...
1
vote
2answers
60 views
VS2013: Potential issue with optimizing move semantics for classes with vector members?
I compiled the following code on VS2013 (using "Release" mode optimization) and was dismayed to find the assembly of std::swap(v1,v2) was not the same as std::swap(v3,v4). #include <vector> ...
0
votes
1answer
63 views
Is there a std template class for managing an object with a pointer and provide copy/move/assign operations?
I need a template class which: Manages an object through a pointer to keep the owning class as small as possible Provides move/copy/assigment operations, so that I do not need to implement them in ...
0
votes
3answers
62 views
Initializing a unique_ptr in constructor of base class properly
I try to pass an std::unique_ptr to an inherited class, which will forward it to the base class constructor (using an constructor initializer list). If the base class constructor receives an nullptr ...
0
votes
2answers
63 views
Returning a vector, is RVO or a move constructor being applied here?
I have a class, which has a std::vector data member. I then have a simple get member function which simply returns the data member by value. class X{ public: ...
2
votes
2answers
143 views
How do move semantics work with unique_ptr?
I was experimenting with using unique_ptr and wrote some simple code to check how it works with move semantics. #include <iostream> #include <vector> using namespace std; class X { ...
5
votes
2answers
162 views
GCC 4.9's unordered_set and std::move
When moving an unordered_set out on GCC 4.9, and then reusing the moved-from object, I am getting a divide-by-zero when I add to it. My understanding (from ...
4
votes
1answer
273 views
Can a compiler automatically move a function argument if the function call is the return statement?
In the following situation can a compiler automatically move the function argument v or does it have to be declared manually? std::vector Filter(std::vector v); void ...
1
vote
1answer
91 views
Why should I delete move constructor and move assignment operator in a singleton?
I have the following Singleton policy-class implementation: template <typename T> class Singleton { Singleton(){}; // so we cannot accidentally delete it via pointers Singleton(const ...
-1
votes
2answers
86 views
How to implement a c++11 move function for a user-defined class?
I have a user-defined class (tree structure) with implemented move semantics, and a swap function. I would like to implement a move function the proper way, working as standard std::move ...
1
vote
1answer
52 views
Is this an abuse/misuse of Move Semantics?
When people usually discuss or use move semantics, it's usually in the context of moving two classes of the same type. Eg: MyObject(MyObject &&obj) { // Implementation } But what if ...
2
votes
1answer
56 views
Move constructor without implementation, yet it works
Here is some code I wrote to illustrate my question: struct Foo { Foo() {} Foo( Foo && ); Foo( const Foo & ) = delete; }; Foo GetFoo() { return Foo(); } int main() { ...
14
votes
1answer
508 views
Generic conversion operator templates and move semantics: any universal solution?
This is a follow-up of Explicit ref-qualified conversion operator templates in action. I have experimented with many different options and I am giving some results here in an attempt to see if there ...
3
votes
2answers
69 views
Returning an fstream
I have this function: fstream open_user_file() const { ... } but my compiler complains about fstream copy-constructor being implicitly deleted. Given that the compiler performs RVO, why is the ...
1
vote
2answers
84 views
Move semantics for a resource manager class
I am trying to make a resource class for my game (which makes use of the SFML API). Basically I first load the needed resources and then I just get references to them when needed in order to avoid ...
0
votes
2answers
69 views
return types and move semantics [duplicate]
#include <iostream> struct X { X(const char *) { std::cout << 1; } X(const X&) {std::cout << 2;} //copy ctor; X(X&& ) {std::cout << 3;} //Move ctor; ...
3
votes
1answer
146 views
c++ deleted move assignment operator compilation issues
The following code fails with gcc 4.8.0 (mingw-w64) with -O2 -std=c++11 -frtti -fexceptions -mthreads #include <string> class Param { public: Param() : data(new std::string) { } ...
1
vote
1answer
37 views
Assign just constructed unnamed value using move assignment operator
I want to assign just constructed unnamed(I mean "created in place without declaration". Fix me, please, if it isn't correct terminology.) container with a big number of elements to another container, ...
2
votes
2answers
201 views
Is a std::vector<T> movable if T is not movable?
I am getting a crash when trying to move a std::vector<T> where T is clearly not movable (no move constructor/assignment operator was defined, and it contains internal pointers) But why would ...
1
vote
1answer
75 views
remove arbitrary list of items from std::vector<std::vector<T> >
I have a vector of vectors, representing an array. I would like to remove rows efficiently, ie with minimal complexity and allocations I have thought about building a new vector of vectors, copying ...
2
votes
3answers
233 views
C++11 Move constructor optimization
I'm currently trying to get a hang of move constructor. I came upon the following (Compiled using g++ d.cpp --std=c++11 -O3) class A { string _x; public: A(string x) { cout << "default ...
4
votes
3answers
197 views
What are the benefits and risks, if any, of using std::move with std::shared_ptr
I am in the process of learning C++11 features and as part of that I am diving head first into the world of unique_ptr and shared_ptr. When I started, I wrote some code that used unique_ptr ...
0
votes
1answer
30 views
Wrapped reference-counting, questions about move-semantics
I'm working on a class that acts as a scope helper for reference-counted objects. The interface should allow to use the class as follows: { Handle<String> s = ...
1
vote
2answers
63 views
unordered_map of std::ofstream
I'd like to use a std::unordered_map<unsigned,std::ofstream> but failed. Now I wonder whether this is simply impossible, or a compiler issue, or whether I just didn't get it right. The problem ...
1
vote
2answers
71 views
How to implement Scope Guard that restores value upon scope exit?
Would the following be an idiomatic C++11 implementation of a Scope Guard that restores a value upon scope exit? template<typename T> class ValueScopeGuard { public: template<typename ...
16
votes
4answers
2k views
Move constructors and `std::array`
According to N3485 §23.3.2.2: (...) the implicit move constructor and move assignment operator for array require that T be MoveConstructible or MoveAssignable, respectively. So, std::array ...
11
votes
3answers
322 views
Pass-by-value resulting in extra move
I'm trying to understand move semantics and copy/move elision. I would like a class that wraps up some data. I would like to pass the data in in the constructor and I would like to own the data. ...
0
votes
2answers
69 views
How can I move a shared_ptr's data?
I have an easy question about shared pointers and move semantics. Imagine that I have a class with a private member variable like this: class C { private: ...
2
votes
1answer
202 views
C++11 constructor argument: std::move and value or std::forward and rvalue reference
Which of the below two should be preferred and why? struct X { Y data_; explicit X(Y&& data): data_(std::forward<Y>(data)) {} }; vs struct X { Y data_; explicit X(Y ...
3
votes
1answer
153 views
Behavior of mutating STL algorithms acting on sequences of movable but non-copyable objects
If I have a class Foo that is movable but non-copyable and I store it in a std::vector, then would applying an algorithm like partition or sort have any caveats? As part of these algorithms should a ...
3
votes
1answer
95 views
Forcing the copy constructor
I have a function like this: Object Class::function() { Object o; return o; } Now when I call it like this: Object o = Class::function(); it wants to use the move constructor. However I ...
0
votes
1answer
108 views
C++ Move copy constructor and Move Assignment operator
I have made a simple application with move copy constructor and move copy assignment operator and on each of them I have made a cout statement just to tell me, which are being executed. But during ...
1
vote
1answer
62 views
Passing rvalue argument to parameter of non-const lvalue reference
I'm unsure why the following code works (VC++ 2013): void Foo(std::vector<int> &v) { } In main: std::vector<int> v; Foo(std::move(v)); Because there is no Foo defined which takes ...
0
votes
1answer
84 views
How to create a global vector in c++
So, I have this problem. I have two objects, and I need to compare data in each of them, the problem is, when I call a function, I have to send both of them, but my teacher wants me to make it so I ...
6
votes
3answers
228 views
Why do we need to set rvalue reference to null in move constructor?
//code from https://skillsmatter.com/skillscasts/2188-move-semanticsperfect-forwarding-and-rvalue-references class Widget { public: Widget(Widget&& rhs) : pds(rhs.pds) // take ...
2
votes
2answers
209 views
Why doesn't the std::move() of unique_ptr from list<unique_ptr> really move it - in C++11?
The sample code is: using Ptr = std::unique_ptr<int>; Ptr f(bool arg) { std::list<Ptr> list; Ptr ptr(new int(1)); list.push_back(std::move(ptr)); if (arg) { Ptr&& ...
3
votes
2answers
152 views
Force Move semantics
I'm trying to use move semantics (just as an experiment). Here is my code: class MyClass { public: MyClass(size_t c): count(c) { data = new int[count]; } MyClass( ...
3
votes
3answers
83 views
Move Semantics for POD-ish types
Is there any point implementing a move constructor and move assignment operator for a struct or class that contains only primitive types? For instance, struct Foo { float x; float y; ...
2
votes
1answer
174 views
How to move elements out of STL priority queue
C++'s STL priority queue have a void pop() method, and a const ref top() method. Thus, if you want to move elements out of the queue, you have to do something like this: T moved = ...
5
votes
1answer
98 views
Function return values and rvalue references binding
I'm trying to understand move semantics and perfect forwarding in C++ To do this I made next simple program: #include <iostream> struct Test { Test(){ std::cout << "Test()" << ...
0
votes
0answers
65 views
Is it safe to use a “moved” std::string object? [duplicate]
Is the following code safe, or not? std::string str = "asdfasdf"; std::string str2 = std::move(str); str = "qwerty";
0
votes
1answer
50 views
Move constructor for a custom container?
is the move constructor for a class that holds a dynamically allocated array supposed to delete it? For instance I have: template<typename T> class MyVector { public: MyVector() { data = new ...
0
votes
2answers
88 views
What are the operations supported after an object is moved? [duplicate]
If an object is actually moved to another location, what are the operations supported on the original object? To elaborate it, I have a type T with available move constructor. With the following ...
1
vote
0answers
89 views
How to return string by value C++ with move semantics?
I want to have a function that returns a string by value, and i want to move construct another string from that return value. When NRVO/RVO is invoked, the move construktor works fine, no copy is ...
4
votes
1answer
134 views
“Moving out” internal representation of an object. Okay or not?
Suppose I have a class whose internal data representation is, for example, an std::string: class my_type { std::string m_value; ... }; Would it be fine if I can "move out" the internal ...
1
vote
5answers
53 views
Should I use const return type in a simple access member function?
I am still not quite sure about the "move semantics". In a simple point class, class point { private: double xval_, yval_, zval_; public: // Constructs // ... public: // Access ...
0
votes
3answers
81 views
Moving vector from class, return && or move into temporary?
class EntityFactory { public: EntityFactory(tinyxml2::XMLElement * pEntitiesNode); ~EntityFactory(); std::vector< std::unique_ptr<Entity> > && TakeEntities(); ...
|
__label__pos
| 0.930172 |
Full Stack Software Developer - Purwana Tekno, Software Engineer
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Full Stack Software Developer Purwana
As a software engineer, a full stack developer is responsible for designing, developing, and testing software applications. They possess a strong understanding of programming languages, algorithms, and data structures. They leverage their knowledge to write clean and efficient code that meets the requirements of the project. A software engineer's expertise lies in translating business needs into technical solutions and ensuring that the software functions optimally.
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A full stack software developer is proficient in a variety of programming languages, such as JavaScript, Python, Java, and C#, to name a few. They are well-versed in front-end development frameworks like React, Angular, or Vue.js, which enable them to build intuitive user interfaces and responsive web applications. Additionally, they have expertise in back-end technologies like Node.js, Django, or Ruby on Rails, allowing them to develop server-side logic, handle data storage and retrieval, and create APIs for seamless integration with other systems.
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In conclusion, a full stack software developer combines the expertise of a software engineer and the knowledge of a CAD designer to create comprehensive and robust software solutions. They possess a broad range of technical skills and are proficient in both front-end and back-end development. With their ability to work on all layers of an application, full stack software developers are well-equipped to tackle complex software projects and bridge the gap between software engineering and CAD design. Their versatility and expertise make them highly sought-after professionals in the ever-evolving software development industry.
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|
__label__pos
| 0.838036 |
Take the 2-minute tour ×
MathOverflow is a question and answer site for professional mathematicians. It's 100% free, no registration required.
Since Noetherian rings satisfy the ascending chain condition, every such ring must contain infinitely many chains of prime ideals s.t. the heights of these chains are unbounded.
The only example I know of is the one due to Nagata [1962]: we take a polynomial ring in infinitely many variables over a field, and consider the infinite collection of prime ideals formed by disjoint subsets of the variables. Then we localise the ring by the complement of the union of these prime ideals. With a little work, we can show that by appropriate choice of the subsets, the localised ring will be Noetherian and of infinite Krull dimension. Eisenbud (ex. 9.6) provides a good walkthrough.
The question is: what are other examples of Noetherian rings of infinite Krull dimension?
share|improve this question
The fact that Nagata had to come up with a fairly involved construction means that they probably don't come up in practice, so would you like us to look up other artificial examples? – Harry Gindi Apr 12 '10 at 5:05
Such Noetherian rings are pathological by nature, so artificial examples are probably the way to go... working first from geometry, then to the related algebraic treatment? – moby Apr 12 '10 at 5:23
5
The question could be improved by giving it more focus: one could presumably modify Nagata's construction in various small ways -- e.g. by starting with $\mathbb{Z}$ instead of a field -- but you are probably not interested in such examples. So, what kind of features are you looking for in other examples? E.g. "Does there exist a Noetherian ring of infinite Krull dimension such that...X?" By filling in X, you ask a binary question, which all of a sudden mathematicians are interested in answering. Just asking "What's out there?" doesn't have the same appeal. – Pete L. Clark Apr 12 '10 at 7:20
1
The entire point of coming up with pathological examples is to show that certain conditions are necessary. Presumably the only motivation to come up with more pathological examples to illustrate necessity of a specific condition is if they are simpler to construct, or if you've come up with some sort of "construction scheme" that gives you a whole class of pathological examples. – Harry Gindi Apr 12 '10 at 9:14
5
@Harry: Oftentimes one wants to prove a result for all noetherian rings and the infinite dimensional case is a sticking point. For example Lemma 3.1.5 in Brian Conrad's notes on Grothendieck duality has a very nice (and fairly involved) proof due to Gabber. The lemma is almost trivial when the ring has finite Krull dimension. So having examples at hand could be very helpful. – Jesse Burke Apr 12 '10 at 23:33
2 Answers 2
If you check the book "Krull Dimension" Memoirs of the American Mathematical Society 133 1973, you will find examples of commutative Noetherian integral domains of arbitrary infinite ordinal Krull dimension
share|improve this answer
1
The complete reference: R. Gordon and J. C. Robson, Krull dimension, Memoirs Amer. Math. Soc, No. 133 (1973). – YCor Jan 12 '13 at 20:17
As you did not ask your ring to be commutative, you can probably take differential operators on your Nagata's example. You may want to look at the 1982 paper by Goodearl and Warfield where they construct a commutative ring and its differential operator ring, both of which have infinite Krull dimensions.
share|improve this answer
Your Answer
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|
__label__pos
| 0.531256 |
1
I have a contract called AccessControl, in which the owner of the contract is set when it is deployed.
I want to test that the method on it setCEO updates correctly, but in order to do this the request must come from the owner of the contract.
contract AccessControl {
address public ceoAddress;
modifier onlyCEO() {
require(msg.sender == ceoAddress);
_;
}
function setCEO(address _newCEO) external onlyCEO {
require(_newCEO != address(0));
ceoAddress = _newCEO;
}
}
When I console.log in the tests the current ceoAddress like so:
const paymentPipe = await PaymentPipe.deployed();
console.log(await paymentPipe.ceoAddress());
I see that the address is 0x0000000000000000000000000000000000000000.
When I try to call setCEO in my tests from that account like so:
await paymentPipe.setCEO(bob, {from: contractAddress});
Truffle complains:
Error: sender account not recognized
If I try with any other account in the truffle test suite (i.e. accounts[x]) I get:
Error: VM Exception while processing transaction: revert
Implying that the method did not pass the require statement because the calling address was not the one set as CEO.
What address are contracts deployed from in the truffle test suite? And why, if I can see an address in my contract as 0x0000000000000000000000000000000000000000 can I not use this address to call functions?
• 1
Hi there. Just to check, because it's not included in your contract snippet: does your contract include a constructor, and are you certain it sets ceoAddress as msg.sender? – Richard Horrocks Aug 2 '18 at 19:04
• @RichardHorrocks thank you, this was indeed the problem! – CollaborativeLearner Aug 2 '18 at 20:22
2
I think your problem appear because ceoAddress is not initialized properly, and it will have the value of 0x0000000000000000000000000000000000000000.
Now to change it the contract requires msg.sender == ceoAddress, this implies that msg.sender should be 0x0000000000000000000000000000000000000000. This operation can't be done because you do not have the private key that generates such address.
One options is to initialize your variable in the constructor with the sender account
contract AccessControl {
address public ceoAddress;
modifier onlyCEO() {
require(msg.sender == ceoAddress);
_;
}
constructor() {
// ---- Initialize ceoAddress ----
ceoAddress = msg.sender;
}
function setCEO(address _newCEO) external onlyCEO {
require(_newCEO != address(0));
ceoAddress = _newCEO;
}
}
Truffle uses the first address returned by eth.accounts to deploy contracts.
2_deploy_contracts.js
module.exports = function(deployer, network, accounts) {
// You can pass other parameters like gas or change the from
deployer.deploy(AccessControl, { from: accounts[2] });
}
Check Truffle documentation for more options to use.
Your Answer
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|
__label__pos
| 0.904709 |
Testing Cookies on a Web Server in PHP
Q
How To Test Cookies on a Web Server in PHP?
✍: FYIcenter.com
A
If you want to test cookies with a browser, you need to run a Web server locally, or have access to a Web server remotely. Then you can copy the following PHP cookie test page, setting_receiving_cookies.php, to the Web server:
<?php
setcookie("LoginName","FYICenter");
setcookie("PreferredColor","Blue");
print("<pre>\n");
print("2 cookies were delivered.\n");
if (isset($_COOKIE["LoginName"])) {
$loginName = $_COOKIE["LoginName"];
print("Received a cookie named as LoginName: ".$loginName."\n");
} else {
print("Did not received any cookie named as LoginName.\n");
}
$count = count($_COOKIE);
print("$count cookies received.\n");
foreach ($_COOKIE as $name => $value) {
print " $name = $value\n";
}
print("</pre>\n");
?>
If you open this PHP page with a browser as http://localhost/setting_receiving_cookies.php, you will get:
2 cookies were delivered.
Did not received any cookie named as LoginName.
0 cookies received.
"0 cookies received" is because there was no previous visit from this browser. But if you click the refresh button of your browser, you will get:
2 cookies were delivered.
Received a cookie named as LoginName: FYICenter
2 cookies received.
LoginName = FYICenter
PreferredColor = Blue
Understanding and Managing Cookies in PHP
⇒⇒PHP Tutorials
2016-11-04, 236👍, 0💬
|
__label__pos
| 0.991411 |
summaryrefslogtreecommitdiffhomepage
path: root/host/simu/view/table_eurobot2012.py
blob: 89ada042e9dbd162bbd9b3643e64231acdf531f3 (plain)
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# simu - Robot simulation. {{{
#
# Copyright (C) 2011 Nicolas Schodet
#
# APBTeam:
# Web: http://apbteam.org/
# Email: team AT apbteam DOT org
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
#
# }}}
"""Eurobot 2012 table."""
from simu.inter.drawable import Drawable
import math
from math import pi
PURPLE = '#a737ff'
RED = '#fe4543'
BLUE = '#01c3ff'
GREEN = '#81ff00'
BLACK = '#1f1b1d'
YELLOW = '#f7ff00'
WHITE = '#f5fef2'
TRANS = '#c0c2b5'
BROWN = '#9d4e01'
def draw_coin (d, coin):
d.trans_push ()
color = WHITE if coin.value else BLACK
d.draw_circle ((0, 0), coin.radius, fill = color)
d.draw_circle ((0, 0), 7.5, fill = color)
d.trans_translate ((40.5, 0))
d.draw_rectangle ((-9, -9), (9, 9), fill = color, outline = TRANS)
d.trans_pop ()
class Coin (Drawable):
def __init__ (self, onto, model):
Drawable.__init__ (self, onto)
self.model = model
self.model.register (self.__notified)
self.__notified ()
def __notified (self):
self.pos = self.model.pos
self.angle = self.model.angle
self.update ()
def draw (self):
self.reset ()
if self.pos:
self.trans_translate (self.pos)
self.trans_rotate (self.angle)
draw_coin (self, self.model)
Drawable.draw (self)
def draw_gold_bar (d, gold_bar):
d.draw_rectangle ((-gold_bar.dim[0] / 2, -gold_bar.dim[1] / 2),
(gold_bar.dim[0] / 2, gold_bar.dim[1] / 2), fill = YELLOW)
d.draw_rectangle ((-gold_bar.dim[0] / 2 + 13, -gold_bar.dim[1] / 2 + 13),
(gold_bar.dim[0] / 2 - 13, gold_bar.dim[1] / 2 - 13), fill = YELLOW)
class GoldBar (Drawable):
def __init__ (self, onto, model):
Drawable.__init__ (self, onto)
self.model = model
self.model.register (self.__notified)
self.__notified ()
def __notified (self):
self.pos = self.model.pos
self.angle = self.model.angle
self.update ()
def draw (self):
self.reset ()
if self.pos:
self.trans_translate (self.pos)
self.trans_rotate (self.angle)
draw_gold_bar (self, self.model)
Drawable.draw (self)
class Table (Drawable):
"""The table and its elements."""
def __init__ (self, onto, model):
Drawable.__init__ (self, onto)
self.model = model
for e in self.model.coins:
if e.level <= 2:
Coin (self, e)
for e in self.model.gold_bars:
GoldBar (self, e)
for e in self.model.coins:
if e.level > 2:
Coin (self, e)
def draw_both (self, primitive, *args, **kargs):
"""Draw a primitive on both sides."""
primitive (*args, **kargs)
primitive (*((3000 - x, y) for x, y in args), **kargs)
def draw (self):
# Redraw.
self.reset ()
# Table.
self.draw_rectangle ((-22, -22), (3000 + 22, 2000 + 22), fill = BLUE)
self.draw_rectangle ((0, 0), (3000, 2000), fill = BLUE)
# Start zones.
self.draw_rectangle ((0, 2000 - 500), (500, 2000), fill = PURPLE)
self.draw_rectangle ((3000, 2000 - 500), (3000 - 500, 2000), fill = RED)
# Black lines.
pup = 2000 - 500 + 50
self.draw_both (self.draw_polygon, (500, pup), (650, pup), (650, 0), (630, 0),
(630, pup - 20), (500, pup - 20), fill = BLACK, outline = 'black')
# Ships.
ba = 0.04995839
self.draw_both (self.draw_polygon, (0, 2000 - 500), (400, 2000 - 500), (325, 0), (0, 0),
fill = BROWN, outline = 'black')
self.draw_both (self.draw_rectangle, (0, 2000 - 500), (400, 2000 - 500 - 18), fill = BROWN)
cba = 750 * math.cos (ba)
sba = 750 * math.sin (ba)
self.draw_both (self.draw_polygon, (325, 0), (325 + sba, cba), (325 + sba + 18, cba), (325 + 18, 0),
fill = BROWN, outline = 'black')
self.draw_both (self.draw_rectangle, (-22, -22), (340, 610 - 22), fill = TRANS)
self.draw_both (self.draw_rectangle, (-4, -4), (340 - 18, 610 - 22 - 18), fill = TRANS)
# Peanut island.
self.draw_both (self.draw_circle, (1500 - 400, 1000), r = 300, fill = YELLOW)
self.draw_rectangle ((1500 - 400 + 141, 1000 + 265), (1500 + 400 - 141, 1000 - 265), fill = YELLOW, outline = '')
self.draw_arc ((1500, 1000 + 750), 550, start = pi + 1, extent = pi - 2, fill = BLUE, outline = '')
self.draw_arc ((1500, 1000 + 750), 550, start = pi + 1.08083, extent = pi - 2 * 1.08083, style = 'arc')
self.draw_arc ((1500, 1000 - 750), 550, start = 1, extent = pi - 2, fill = BLUE, outline = '')
self.draw_arc ((1500, 1000 - 750), 550, start = 1.08083, extent = pi - 2 * 1.08083, style = 'arc')
self.draw_both (self.draw_circle, (1500 - 400, 1000), r = 200, fill = GREEN)
self.draw_circle ((1500, 1000), r = 75, fill = GREEN)
self.draw_both (self.draw_rectangle, (1500 - 400 - 125, 1000 - 125), (1500 - 400 + 125, 1000 + 125), fill = BROWN)
# Map island.
self.draw_arc ((1500, 2000), 400, start = pi, extent = pi, fill = YELLOW)
self.draw_arc ((1500, 2000), 300, start = pi, extent = pi, fill = GREEN)
# Map.
self.draw_rectangle ((1500 - 200 - 22, 2000 + 148), (1500 + 200 + 22, 2000 + 140), fill = BLUE)
self.draw_rectangle ((1500 - 200, 2000 + 140), (1500 + 200, 2000 - 8), fill = BLUE)
self.draw_both (self.draw_rectangle, (1500 - 200 - 22, 2000 + 140), (1500 - 200, 2000 + 125), fill = BLUE)
self.draw_both (self.draw_rectangle, (1500 - 200 - 22, 2000 + 125), (1500 - 200, 2000 - 23), fill = BLUE)
self.draw_rectangle ((1500 - 22, 2000 + 140), (1500 + 22, 2000 + 125), fill = BLUE)
self.draw_rectangle ((1500 - 22, 2000 + 125), (1500 + 22, 2000 + 115), fill = BLUE)
self.draw_rectangle ((1500 - 22, 2000 + 2), (1500 + 22, 2000 - 13), fill = BLUE)
self.draw_rectangle ((1500 - 22, 2000 - 13), (1500 + 22, 2000 - 23), fill = BLUE)
# Bottles.
def draw_bottle (x, color):
self.draw_rectangle ((x - 100, 0), (x + 100, -44), fill = color)
self.draw_rectangle ((x - 100, -44), (x + 100, -66), fill = color)
self.draw_rectangle ((x - 11, 44), (x + 11, 0), fill = color)
self.draw_rectangle ((x - 50, 22), (x + 100, -44), fill = color)
self.draw_polygon ((x - 50, 22), (x - 80, 0), (x - 100, 0), (x - 100, -22), (x - 80, -22), (x - 50, -44),
fill = color, outline = 'black')
draw_bottle (640, PURPLE)
draw_bottle (640 + 477, RED)
draw_bottle (3000 - 640, RED)
draw_bottle (3000 - 640 - 477, PURPLE)
# Axes.
self.draw_line ((0, 200), (0, 0), (200, 0), arrow = 'both')
# Beacons.
self.draw_both (self.draw_rectangle, (-22, 2000 + 22), (-22 - 80, 2000 + 22 + 80), fill = BLACK)
self.draw_both (self.draw_rectangle, (-22, 1000 - 40), (-22 - 80, 1000 + 40), fill = BLACK)
self.draw_both (self.draw_rectangle, (-22, -80 - 22), (-22 - 80, -22), fill = BLACK)
# Children.
Drawable.draw (self)
if __name__ == '__main__':
from simu.inter.inter import Inter
import simu.model.table_eurobot2012 as model
app = Inter ()
m = model.Table ()
Table (app.table_view, m)
app.mainloop ()
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Odpowiedzi
2010-02-03T21:43:35+01:00
A) 27 i 243
q = 243:27 = 9
q = 9
b) 8/9 i 4/3
q = 4/3 : 8/9 = 4/3 * 9/8 = 36/24 = 6/4 = 3/2
q = 3/2 lub q = 1 i 1/2
c) -216 i -36
q = (-36) : (-216) = 36/216 = 1/6
q = 1/6
d) - 6/5 i 9/10
q = 9/10 : (-6/5) = 9/10 * (-5/6) = -45/60 = -3/5
q = -3/5
e) √2 i -4
q = (-4) : √2 = -4/√2 = -4*√2/√2*√2 = -4√2/2 = -2√2
q = -2√2
f) 2√3 i 3√2
q = 3√2 : 2√3 = 3√2/2√3 = 3√2*2√3/2√3*2√3 = 6√6/12 = √36*√6/12 = 6√6/12
q = ½√6
co do tego ostatniego nie jestem do końca pewna... sprawdź najlepiej w odpowiedziach :)
3 4 3
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Boolean simplifier.
Simplifier.cs source code in C# .NET Source code for the .NET framework in C#
Boolean simplifier. Things To Know About Boolean simplifier.
The online calculator allows you to quickly build a truth table for an arbitrary Boolean function or its vector, calculate perfect disjunctive and perfect conjunctive normal forms, find function representation in the form of the Zhegalkin polynomial, build a K-Map (Karnaugh Map), and classify the function by classes of Post (Post Emil Leon). Learn Boolean algebra basics and explore various features for your logic circuit designs. BooleanTT - Beta - Online Boolean Algebra BooleanTT is a powerful and lightweight app for Boolean algebra simplification, logic circuit simulation and generation, Karnaugh map solving, number system calculations, and more. CS111, Wellesley College, Spring 2000 Simplifying Boolean Expressions and Conditionals. When writing methods that return booleans, many people make their code much more complicated than it needs to be. For instance, suppose you want a method that detects if a buggle has a wall both to its left and its right. One way of doing this is as …There are two versions included in this repository. You can find the original simplifier here or under the deprecated folder while the new JavaFX application is under development using Java 8. Current Features: Allow simplification of boolean expressions from truth-table; Custom UI components (scalable truth-table) for ease of useBoolean Rules for Simplification. PDF Version. Boolean algebra finds its most practical use in the simplification of logic circuits. If we translate a logic circuit’s function into symbolic (Boolean) form, and apply certain algebraic rules to the resulting equation to reduce the number of terms and/or arithmetic operations, the simplified ...
Enter the statement: [Use AND, OR, NOT, XOR, NAND, NOR, and XNOR, IMPLIES and parentheses]Expression Simplifier. This widget allows beginning algebra students to check their simplification of algebraic expressions. Get the free "Expression Simplifier" widget for your website, blog, Wordpress, Blogger, or iGoogle. Find more Mathematics widgets in …
boolean algebra. Have a question about using Wolfram|Alpha? Contact Pro Premium Expert Support ». Compute answers using Wolfram's breakthrough technology & knowledgebase, relied on by millions of students & professionals. For math, science, nutrition, history, geography, engineering, mathematics, linguistics, sports, finance, music….
Boolean expression expression simplifier SOP & solver. Detailed steps, Logic circuits, KMap, Truth table, & Quizes. All in one calculator.There are 2 methods to find the Boolean equation from the truth table, either by using the output values 0 (calculation of Maxterms) or by using output values 1 (calculation of Minterms ). Example: The output values are 0,1,1,0, (and the table is ordered from 00 to 11), so the truth table is: input. A.The Distributive Property. Lastly, we have the distributive property, illustrating how to expand a Boolean expression formed by the product of a sum, and in reverse shows us how terms may be factored out of Boolean sums-of-products: To summarize, here are the three basic properties: commutative, associative, and distributive. RELATED …Simplification / Minimization of a Boolean function Step-by-Step solution mentioning Boolean Law used at each step. Quine McCluskey method or Tabulation method From truth table by entering minterms and don't cares. Generate Circuit using Common gates, NAND Only and NOR Only Gates. Truth Table Generate TT from equation.
Enter the statement: [Use AND, OR, NOT, XOR, NAND, NOR, and XNOR, IMPLIES and parentheses]
1. There's a nice online tool - tma.main.jp/logic/index_en.html. – Roman Hocke. May 18, 2017 at 6:53. Another tool is boolean-algebra.com it will show the steps to solve it. For …
Anything complemented twice is equal to the original. 4.png; The two variable rule. 3.png. Simplification of Combinational Logic Circuits Using Boolean Algebra.The Karnaugh map, also known as K-map, was invented in 1953 by Maurice Karnaugh, a physicist and mathematician at Bell Laboratories. The map is primarily used to simplify Boolean functions, especially those represented by truth tables or complicated algebraic expressions. The Karnaugh map represents all possible combinations of inputs in a two ...Co-parenting can be a challenging task, especially when it comes to effective communication and coordination between two parents. However, with the help of technology, there are no...Free simplify calculator - simplify algebraic expressions step-by-step. Boolean Algebra is used to simplify and analyze the digital (logic) circuits. It has only the binary numbers i.e. 0 (False) and 1 (True). It is also called Binary Algebra or logical Algebra. Boolean Algebra Calculator makes your calculations easier and solves your questions. Check steps to solve boolean algebra expression, laws of boolean algebra.
Step 1: Make k-map. Step 2: Place the minterms and don’t cares. Step 3: Make groups. Two quads and a singleton are formed. As you can see the second quad used the don’t care values as 1. Step 4: Write the binary value of groups. Step 5: Write the sum of … Boolean Algebra expression simplifier & solver. Detailed steps, Logic circuits, KMap, Truth table, & Quizes. All in one boolean expression calculator. Online tool. Co-parenting can be a challenging task, especially when it comes to effective communication and coordination between two parents. However, with the help of technology, there are no...The Distributive Property. Lastly, we have the distributive property, illustrating how to expand a Boolean expression formed by the product of a sum, and in reverse shows us how terms may be factored out of Boolean sums-of-products: To summarize, here are the three basic properties: commutative, associative, and distributive. RELATED …Solve practice querys using an online SQL terminal. Boolean Algebra expression simplifier & solver. Detailed steps, Logic circuits, KMap, Truth table, & Quizes. All in one boolean expression calculator. Online tool.The Karnaugh map, also known as K-map, was invented in 1953 by Maurice Karnaugh, a physicist and mathematician at Bell Laboratories. The map is primarily used to simplify Boolean functions, especially those represented by truth tables or complicated algebraic expressions. The Karnaugh map represents all possible combinations of inputs in a two ...
There are some computer algebra systems that can simplify boolean expressions using the Quine-McCluskey algorithm, such as Sympy. Quine-McCluskey is the grandfather of two-level minimization. Espresso came 30 years later in 1986. It would be interesting to learn about recent developments in this field.
There are 2 methods to find the Boolean equation from the truth table, either by using the output values 0 (calculation of Maxterms) or by using output values 1 (calculation of Minterms ). Example: The output values are 0,1,1,0, (and the table is ordered from 00 to 11), so the truth table is: input. A.Project description. This library helps you deal with boolean expressions and algebra with variables and the boolean functions AND, OR, NOT. You can parse expressions from strings and simplify and compare expressions. You can also easily create your custom algreba and mini DSL and create custom tokenizers to handle custom …Online minimization of boolean functions. October 9, 2011 Performance up! Reduce time out errors. Heavy example. Karnaugh map gallery. Enter boolean functions. Notation. not A => ~A (Tilde) A and B => AB A or B => A+B A xor B => A^B (circumflex)Karnaugh Map (Kmap solver) calculator - AtoZmath.comBinary and Boolean Examples. Truth Table Examples: Boolean Expression Simplification: Logic Gate ExamplesHere are some examples of Boolean algebra simplifications. Each line gives a form of the expression, and the rule or rules used to derive it from the previous one. Generally, there are several ways to reach the result. Here is the list of simplification rules. Simplify: C …Jul 16, 2019 ... Q. 2.3: Simplify the following Boolean expressions to a minimum number of literals: (a) ABC + A'B + ABC' (b) x'yz + xz (c) (x + y)'(x' + y'...
I am creating a Boolean algebra simplifier in C# for a project. To simplify Boolean algebraic expressions, I am taking the following approach: 1)Simplify the NOTs over each variable and apply De Morgan's Law where applicable. 2)Simplify the brackets, if there are any, within the expression. 3)Expand any brackets within the expression that …
Are you tired of spending hours in the kitchen trying to come up with new and exciting recipes? Look no further. In this article, we will introduce you to a delicious and easy basi...
In mathematics and mathematical logic, Boolean algebra is a branch of algebra. It differs from elementary algebra in two ways. First, the values of the variables are the truth values true and false, usually denoted 1 and 0, whereas in elementary algebra the values of the variables are numbers. Second, Boolean algebra uses logical operators such ...OR: Takes two boolean inputs and returns true if at least one is true. NOT: Takes one boolean input and returns the opposite value. Boolean Algebra Laws. Boolean Algebra operates under certain laws like Commutative, Associative, and Distributive laws, which make it easier to manipulate and simplify Boolean expressions. The Role of Claude ShannonBoolean Algebra expression simplifier & solver. Detailed steps, Logic circuits, KMap, Truth table, & Quizes. All in one boolean expression calculator. Online tool. Learn boolean algebra.In mathematics and mathematical logic, Boolean algebra is a branch of algebra. It differs from elementary algebra in two ways. First, the values of the variables are the truth values true and false, usually denoted 1 and 0, whereas in elementary algebra the values of the variables are numbers. Second, Boolean algebra uses logical operators such ...2.2: Boolean Algebra. Exam Board: Eduqas / WJEC. Specification: 2020 +. Boolean algebra is used to simplify Boolean expressions so that they are easier to understand. Because calculations can use dozens of logical operators, they are simplified in Boolean Algebra using symbols rather than words.4. One common technique used to simplify complex Boolean expressions is Karnaugh Maps. It is relatively easy to learn, and it can help you produce shorter expressions, or even build Boolean expressions from a truth table. Karnaugh Map for your expression is very simple - it looks like this:Enter the statement: [Use AND, OR, NOT, XOR, NAND, NOR, and XNOR, IMPLIES and parentheses] Enter the statement: [Use AND, OR, NOT, XOR, NAND, NOR, and XNOR, IMPLIES and parentheses]
I am creating a Boolean algebra simplifier in C# for a project. To simplify Boolean algebraic expressions, I am taking the following approach: 1)Simplify the NOTs over each variable and apply De Morgan's Law where applicable. 2)Simplify the brackets, if there are any, within the expression. 3)Expand any brackets within the expression that … Experiment with resource instance generation using YamlGen and based on this profile. This feature is in beta. You can help us improve it by giving feedback with the feedback button at the top of the screen. Simplify Boolean expressions with the 2023 version of the 'Boolean Simpifier' software. * Manage truth tables of expressions with up to 26 logic inputs; * Generate truth tables with random outputs; * Create Karnaugh maps from generated truth tables; * Conversion of Boolean expressions to 64 different types of Boolean logic language; * Create expressions in POS (Product of Sums) or SOP (Sum of ... Boolean Algebra is used to simplify and analyze the digital (logic) circuits. It has only the binary numbers i.e. 0 (False) and 1 (True). It is also called Binary Algebra or logical Algebra. Boolean Algebra Calculator makes your calculations easier and solves your questions. Check steps to solve boolean algebra expression, laws of boolean algebra. Instagram:https://instagram. does burlington take apple paysayt dnyaharbor freight duncan oklahomahelicopter 2 person In today’s fast-paced business environment, companies need efficient and reliable banking solutions to keep up with their financial needs. Straight2BankBotswana is a cutting-edge p... rio da yung og quotescb scanner twitter Allows the user to input values for a Karnaugh map and recieve boolean expressions for the output. Karnaugh Map Solver. Skip to main. Function Info. Output Name: ... new star med spa Switching Theory allows us to understand the operation and relationship between Boolean Algebra and two-level logic functions with regards to Digital Logic Gates.Switching theory can be used to further develop the theoretical knowledge and concepts of digital circuits when viewed as an interconnection of input elements …Boolean Calculator is a tool that simplifies the propositional logic statements by converting them to equivalent expressions and showing the steps. You can choose from different rules, such as commutative, associative, distributive, identity, negation, double negation, and more, and preview the result before saving it.Examples. ~ ( (~A+B) (~B+C)) Calculate the simplified forms of your boolean algebra expressions step by step.
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__label__pos
| 0.880395 |
Unification of date and time data with joda in Spark
Here is the code snippet which can first parse various kind of date and time formats and then unify them together to be processed by data munging process.
import org.apache.spark.sql.functions._
import org.joda.time._
import org.joda.time.format._
import org.apache.spark.sql.expressions.Window
val getHour = udf((dt:String) =>
dt match {
case null => None
case s => {
val fmt:DateTimeFormatter = DateTimeFormat.forPattern("MM/dd/yyyy hh:mm:ss aa")
Some(fmt.parseDateTime(s).getHourOfDay)
}
})
val getDT = udf((dt:String) =>
dt match {
case null => None
case s => {
val fmt:DateTimeFormatter = DateTimeFormat.forPattern("MM/dd/yyyy hh:mm:ss aa")
Some(fmt.parseDateTime(s).getMillis / 1000.0 )
}
})
// UDF for day of week
val getDayOfWeek = udf((dt:String) => {
dt match {
case null => None
case s => {
val fmt:DateTimeFormatter = DateTimeFormat.forPattern("MM/dd/yyyy")
Some(fmt.parseDateTime(s.split(" ")(0)).getDayOfWeek)
}
}
})
val getDate = udf((dt:String) => {
dt match {
case null => None
case s => {
Some(s.split(" ")(0))
}
}
})
val getDiffKey = udf((diff:Double) => {
val threshold = 5 // 15 minutes 5 // 75%-tile seconds
if (diff > threshold) {
1 // tag as 2nd diff
} else {
0 // 1st diff
}
})
val rawDF = sqlContext.read
.format("com.databricks.spark.csv")
.option("header", "true")
.load("hdfs://mr-0xc5.0xdata.loc:8020/user/file.csv")
var df = rawDF.withColumn("hourOfDay", getHour(rawDF.col("datetime")))
df = df.withColumn("timestamp", getDT(df.col("datetime")))
df = df.withColumn("dayOfWeek", getDayOfWeek(df.col("datetime")))
df = df.withColumn("date", getDate(df.col("datetime")))
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| 0.963422 |
Cyber Security
Information Gathering: Concepts, Techniques and Tools Explained
Information Gathering: Concepts, Techniques and Tools Explained
Reading Time: 3 minutes
What is Information Gathering?
Information gathering is a process of collecting information from different sources, such as books, websites, interviews, surveys, and more. This process is used to gather information about a particular topic or issue. It helps to create a comprehensive picture of the subject, and is essential for making informed decisions. By gathering information, organizations, and individuals can better understand the environment in which they operate, identify potential risks, develop strategies, and make informed decisions. Additionally, information gathering can help to inform public policy and create public awareness on important topics.
Importance of Information Gathering in Cyber Security
Information gathering is an essential part of cyber security. By gathering information, organizations can better understand their networks, identify potential threats and vulnerabilities, and develop strategies to protect their systems. Additionally, information gathering can help organizations detect and respond to cyber-attacks, as well as help them develop better security practices. Information gathering can also be used to identify malicious actors, establish a baseline of normal network activity, and uncover suspicious patterns of behaviour. Finally, information gathering can help organizations develop better cyber security policies, procedures, and training programs.
Type of Information Required in Cyber Security
The type of information required in cyber security depends on the organization’s goals and objectives. Generally, organizations should collect information about their networks, including details about hardware and software, as well as data about users and their access privileges. Organizations should also gather information about the threats and vulnerabilities they face, as well as information about the malicious actors they may encounter. Additionally, organizations should collect information about their policies and procedures, as well as their security practices. Finally, organizations should collect information about their compliance requirements and the laws and regulations they must abide by.
Information Gathering Techniques
Information gathering techniques vary depending on the type of information being collected. Generally, these techniques can be divided into two categories: active and passive. Active techniques involve actively probing a network or system to collect information, while passive techniques involve listening for information without sending any data or requests. Examples of active techniques include port scanning, vulnerability scanning, and protocol analysis. Examples of passive techniques include traffic analysis, log analysis, and packet capture.
Information Gathering Tools
There are many different tools available for information gathering. Network mapping tools can be used to create a visual representation of an organization’s network, while vulnerability scanners can be used to identify weaknesses in a system. Protocol analysis tools can be used to analyze the data that is transferred between systems, while traffic analysis tools can be used to monitor and analyze network traffic. Additionally, log analysis tools can be used to identify suspicious activity and packet capture tools can be used to record and analyze packets. Finally, there are also a number of tools available for gathering information from public sources, such as search engines and social media.
Information Gathering Websites
There are a number of websites that can be used for information gathering. Popular search engines such as Google, Bing, and Yahoo are good starting points for gathering information. Additionally, social media sites such as Twitter, Facebook, and LinkedIn can be used to gather information about people and organizations. Government websites, such as the US Census Bureau, can also be used to gather information about specific demographics. Finally, there are also a number of websites dedicated to cyber security, such as security blogs and forums, which can provide valuable insight about the latest threats and vulnerabilities.
Information Gathering Phases
The information gathering process typically involves four phases: identification, collection, analysis, and reporting. In the identification phase, the information to be gathered is identified, and the sources of data are identified and categorized. In the collection phase, the data is gathered from the identified sources. In the analysis phase, the data is analyzed to extract useful information and insights. In the reporting phase, the gathered information is reported in a format that is easy to understand and interpret.
Information Gathering By Cyber Criminals
Cyber criminals use a variety of techniques to gather information. These techniques are generally divided into two categories: active and passive. Active techniques involve actively probing a system or network to collect information, while passive techniques involve listening for information without sending any data or requests. Examples of active techniques include port scanning, vulnerability scanning, and protocol analysis. Examples of passive techniques include traffic analysis, log analysis, and packet capture. Cybercriminals also use social engineering techniques such as phishing and social media scraping to collect data about individuals and organizations.
Conclusion:
Information gathering is an essential process for cyber security. By gathering information, organizations can better understand their networks, identify potential threats and vulnerabilities, and develop strategies to protect their systems. Additionally, information gathering can help organizations detect and respond to cyber-attacks, as well as help them develop better security practices. There are a variety of techniques and tools that can be used for information gathering, including search engines, social media, network mapping tools, vulnerability scanners, and more. Cybercriminals also use a variety of techniques to gather information, such as port scanning, social engineering, and packet capture.
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Tell me more ×
Mathematica Stack Exchange is a question and answer site for users of Mathematica. It's 100% free, no registration required.
I'm trying to solve the following differential equation numerically:
s = NDSolve[{
(z + 2 r[z] r'[z]) (1 + r'[z]^2) -z r[z] r''[z] == 0,
r[0.01] == 0.0001,
r'[0.01] == 10
},
r, {z, 0.01, 10}
]
But, when I set the initial condition to $z=0$, there are singularities, so I tried to set it as 0.01. Also, for $r(z=0.01)=0$ there is a singularity, so I set $r(z=0.01)=0.0001$.
However, when I try to solve the equation for any value that I put in the boundary conditions, I'm getting "step size is effectively zero; singularity or stiff system suspected." Is there any method to sort this out?
share|improve this question
The singularity is clear: this equation algebraically implies $r'' = (1+r'^2)\frac{1}{r}$ plus other stuff not involving $r$. Because $1+r'^2\ge 1$ (assuming you want non-Complex solutions), it would be hard for $r$ to approach $0$ while its second derivative is blowing up like $1/r$. This indicates you will have extreme trouble finding any solution for small values of $r$. – whuber Oct 3 '12 at 15:56
1 Answer
This problem seems to be really stiff as whuber has pointed out. Using the BDF method and allowing NDSolve to ruminate about the order, didn't quite change the solution (z value where stiffness was encountered).
NDSolve[{(z + 2 r[z] r'[z]) (1 + r'[z]^2) - z r[z] r''[z] == 0,
r[0.01] == 0.0001, r'[0.01] == 10}, r, {z, 0.01, 10},
MaxStepFraction -> 1/101,
Method -> {"BDF", "MaxDifferenceOrder" -> 5}]
Try these commands out as pointed out by several authors here and here:
These answers helped me out with issues I had with stiff equations.
You can look around and find heaps more information.
?NDSolve`BDF
?NDSolve`LSODA
share|improve this answer
Huh, I haven't said anything about these equations. You intended to address whuber? – J. M. Oct 3 '12 at 16:14
@J.M. Yes, I meant whuber... I think I got that wrong. – drN Oct 3 '12 at 20:44
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|
__label__pos
| 0.568005 |
Metrestick fractions-decimals-percentages
(first published in the SMC Journal Issue 48)
In my last article, I shared what a fantastic resource metre sticks are for teaching early addition and subtraction skills. In this article I will highlight how they are also great for teaching fractions, decimal fractions and percentages in upper primary.
Halves and mixed numbers
Let’s assume your pupils already have a secure understanding of the idea that a fraction is part of a whole and are confident in using fraction notation. Now introduce the metre stick!
The whole stick is one metre (1m). The graduations show centimetres (cm). There are 100 centimetres in a metre. How many centimetres in two metres? How many in no metres? How long is half a metre? What about no halves? What about two halves? Is it possible to have three halves? Yes! If you use another metre stick! What about four or five halves? How many centimetres is that? New idea: 11⁄2m and 21⁄2m are called mixed numbers. Mixed numbers are made up of wholes and fractions.
Quarter metres & improper fractions
Once the children have grasped the idea of halves we can then move on to quarters. How can we divide the metre stick into four equal pieces? Where would 1⁄4 of a metre be? What about 0, 2, 3, 4 quarters of a metre?
Can you get five quarters? Yes! This would be 1 1⁄4 metres or 125cm. How about six quarter metres? We can write 5, 6 or 7 over 4. These are called improper fractions.
Decimal fractions and equivalences
To understand common and improper fractions well, children need to understand their relationship with decimal fractions. First explore tenths. How can we split the metre stick into ten equal parts? What fraction of the metre stick is each part? Point out that each coloured section is one tenth of the metre stick, or 10cm. How many centimetres in 4/10, 7/10, 9/10 of a metre?
We can write one tenth like this: 0∙1. We say ‘zero point one’. The zero shows there are no whole metres and the one shows we have one coloured section, or one tenth. How would you write two tenths as a decimal? How would you read that?
Where is 1⁄2m? How many tenths is that? How could we write 1⁄2m as a decimal fraction? How would you read it?
Ten tenths is one whole metre. Can you get 11 tenths? Yes! You need another metre stick! One whole metre and one tenth of a metre can be written as 1∙1. What do you think 1∙2 means? How about 1.7 etc.?
How could you divide the metre stick into five equal pieces? [see ‘Chopping up a Metre Stick’ for a more in depth practical investigation] What fraction of the metre stick is each piece? One fifth of a metre = 20cm = 0.2m. What would two fifths of a metre be? How about three fifths, four fifths, five fifths? Which is bigger, one fifth or one tenth? How do you know? We say 1 fifth is equivalent to 2 tenths. What other equivalences can you find? (2 fifths = 4 tenths, 3 fifths = 6 tenths etc.)
Add an element of challenge by introducing twentieths. Which is bigger: one twentieth or one fifth? How many times bigger / smaller is a fifth compared to a twentieth / tenth? What other equivalences can you find between fifths, tenths and twentieths?
Percentages
If one hundred percent (100%) equals one whole how would you show 1% on your metre stick? Suddenly all the easy equivalences between fractions, decimal fractions and percentages are open to us:
One quarter of a metre = 25cm = 25%. How would you write two quarters, three quarters as percentages?
1 fifth of a metre = 20cm =20%. How would you write two fifths, three fifths, four fifths as percentages?
1 twentieth of a metre = 5cm = 5%. Challenge the children to find all other equivalences from two twentieths = 10% up to nineteen twentieths = 95%
Extend these ideas further to include twenty-fifths and fiftieths.
Factor rainbows
Finally: if you have never used factor rainbows you have been missing out on something wonderful. [see ‘Multiplication Rectangles and Factor Rainbows’ for a more. In depth investigation of these] Here is the factor rainbow for 100.
Something to puzzle over: What do these numbers have to do with the denominators of the fractions that can be easily converted to percentages? Aha!
Author:
Rob Porteous
Deputy Head, Learning and Teaching, George Watson’s College, Edinburgh
Email: [email protected]
Creator of the Maths Investigations Website.
Author: admin
Leave a Reply
Your email address will not be published. Required fields are marked *
|
__label__pos
| 0.998972 |
Why is $_POST[''] not working with <form>
This is a Rock Paper Scissors game and I am just starting on it, but it will not display the $_POST['keuzen'].
So I don't get why this is not working. Tried many things but can't find a good solution.
<?php session_start(); ?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>RockPaperScissor</title>
</head>
<body>
<form action="RockPaperScissor.php" method="post">
<input type="image" src="steen.jpg" alt="steen" name="keuzen" value="steen" title="Steen">
<input type="image" src="papier.jpg" alt="papier" name="keuzen" value="papier" title="Papier">
<input type="image" src="schaar.jpg" alt="schaar" name="keuzen" value="schaar" title="Schaar">
</form>
<?php
if (isset($_POST['keuzen'])) {
$keuzen = $_POST['keuzen'];
$kiezenuit = array("steen", "papier", "schaar");
$random = rand(0, 2);
$computer = $kiezenuit[$random];
echo 'jij koos ' . $keuzen . '<br>';
echo 'De computer koos ' . $computer . '<br';
if ($keuzen == $computer) {
echo 'Resultaat : Draw ';
}
}
?>
</body>
</html>
Assuming the form is in the same RockPaperScissor.php page, better introduce a hidden field that takes the value of a clicked image, but remove the name tag from the images itself:
<?php session_start(); ?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>RockPaperScissor</title>
</head>
<body>
<form action="RockPaperScissor.php" method="post">
<input type="hidden" name="keuzen" value="">
<input type="image" src="steen.jpg" alt="steen" value="steen" title="Steen" onclick="document.forms[0].keuzen.value=this.value">
<input type="image" src="papier.jpg" alt="papier" value="papier" title="Papier" onclick="document.forms[0].keuzen.value=this.value">
<input type="image" src="schaar.jpg" alt="schaar" value="schaar" title="Schaar" onclick="document.forms[0].keuzen.value=this.value">
</form>
<?php
if (!empty($_POST['keuzen'])) {
$keuzen = $_POST['keuzen'];
$kiezenuit = array("steen", "papier", "schaar");
$random = rand(0, 2);
$computer = $kiezenuit[$random];
echo 'jij koos ' . $keuzen . '<br>';
echo 'De computer koos ' . $computer . '<br>';
if ($keuzen == $computer) {
echo 'Resultaat : Draw ';
}
}
?>
</body>
</html>
Upon POST, you will get the following:
Array
(
[keuzen] => schaar
[x] => 7
[y] => 3
)
jij koos schaar
De computer koos schaar
Resultaat : Draw
PHP: $_POST, $_POST. $HTTP_POST_VARS [deprecated]. (PHP 4 >= 4.1.0, PHP 5, PHP 7). $_ POST --� PHP $_POST. PHP $_POST is a PHP super global variable which is used to collect form data after submitting an HTML form with method="post". $_POST is also widely used to pass variables. The example below shows a form with an input field and a submit button.
The purpose of <input type="image" name="keuzen"> is to provide a server side image map. It submits the form as a side effect, but the purpose is to select coordinates on the image.
When you click it, x and y coordinates will be sent to the server.
If I remember correctly, you'll get something like keuzen.y=123&keuzen.x=456 which PHP will use to populate $_POST['keuzen_x'] and $_POST['keuzen_y'] but not $_POST['keuzen'].
If you do a var_dump($_POST) you can see the data structure you actually get.
If you want to just have regular submit buttons which look like images, then use regular submit buttons containing images:
<button name="keuzen" value="steen"><img src="steen.jpg" alt="steen"></button>
You can style away the borders and background of the button element with CSS if you like.
PHP $_POST, PHP $_POST. PHP $_POST is a PHP super global variable which is used to collect form data after submitting an HTML form with method="post". The $_POST Variable. The $_POST variable is an array of variable names and values sent by the HTTP POST method. The $_POST variable is used to collect values from a form with method="post". Information sent from a form with the POST method is invisible to others and has no limits on the amount of information to send. Example
1. Change names of inputs like this: name="keuzen[steen]" and remove value attributes.
2. Read POSTed value like this: $keuzen = array_keys($_POST['keuzen'])[0];
You can also verify that the POSTed value is not empty.
PHP $_POST, PHP $_POST. PHP $_POST is a PHP super global variable which is used to collect form data after submitting an HTML form with method="post". The problem is that you're checking if $_POST['send'] is set, but it won't be. The "send" field in your form is the button, but the button doesn't have a value, so it won't be included in $_POST. Hope that helps.
$_GET,$_POST, and $_REQUEST, $_GET, $_POST, and $_REQUEST. $_GET Variable. What is it? The $_GET variable is used to get data from a form that is written in HTML. Also in the url� The $_POST variable is also used to collect data from forms, but the $_POST is slightly different because in $_GET it displayed the data in the url and $_POST does not. The data that $_POST gets, is invisible to others and the amount that can be sent is not limited besides the 8MB max size.
What is the purpose of $_POST?, You may want to read up on the basics of PHP. Try reading some starter tutorials. $_POST is a variable used to grab data sent through a web� POST create an array which holds key/value pairs, where keys are the names of the form controls and values are the input data from the user. $_POST is superglobal, which means that it always accessible, regardless of scope - and you can access the
PHP - GET & POST Methods, The PHP provides $_GET associative array to access all the sent information using GET method. Try out following example by putting the source code in test. php� Hi, I have the following code that I want to run only when the “Submit” button is pressed…but a message is echoed even when it has not been clicked…I can’t work out what I need to amend
|
__label__pos
| 0.585784 |
XEON Heatsink/fan question
neljan 01:18 23 Feb 2006
Locked
Hello all,
I'm going to build an Xeon PC and would like to know what the difference between an active / passive heatsink is, and whether I will still need to buy a fan using a passive heatsink.
If so, would the fan need to blow on the CPU or suck from the CPU. Also, the fans I've seen for socket 604 have heatsink included, can I remove the heatsink from the fan & just use the fan?
Bloody jobsworth procedures for a poxy fan!!!
CurlyWhirly 07:12 23 Feb 2006
I can't help you with your Xeon heatsink query but the difference between an active and a passive heatsink is that the active heatsink relies on a fan to keep it cool where as a passive heatsink does not.
These passive heatsinks are usually found on older processors which have slower clock speeds so they produce less heat and therefore they don't need a fan!
neljan 08:52 23 Feb 2006
Thanks, that explains why the passive is more expensive. Maybe I'll see what the manual says when it arrives.
Thanks again.
keef66 11:55 23 Feb 2006
fans usually blow air into the heatsink.
You can't use the fan without the heatsink.
This thread is now locked and can not be replied to.
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|
__label__pos
| 0.610328 |
Login
Translation statistics gatherer
Author:
ramiro
Posted:
August 17, 2008
Language:
Python
Version:
.96
Tags:
internationalization i18n l10n translations status statistics localization
Score:
0 (after 0 ratings)
A script that gathers statistics of translated, untranslated and fuzzy literals of translations (be it Django itself or a project using Django).
For that it re-scans the tree and generates a up-to-date POT in a temporary location, so the statistics of translation "coverage" are calculated relative to the current status of the tree. It doesn't touch the tree it is analyzing at all.
It should be run from the directory containing the locale/ directory of your project or from the django/ directory of a Django copy.
It is based on the makemessages Django management command (or rather its previous standalone make-messages.py script incarnation) and uses the same command line switches:
• -d <domain> -- <domain> is django or djangojs. Optional, defaults to django.
• -l <language> OR
• -a -- process all languages
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#!/usr/bin/env python
# Need to ensure that the i18n framework is enabled
from django.conf import settings
settings.configure(USE_I18N = True)
from django.utils.translation import templatize
import re
import os
import sys
import getopt
from itertools import dropwhile
from tempfile import mkdtemp
from shutil import rmtree
pythonize_re = re.compile(r'\n\s*//')
msgfmt_re = re.compile(r'((?P<transl>\d+) translated messages?)?((, )?(?P<fuzzy>\d+) fuzzy translations?)?((, )?(?P<untransl>\d+) untranslated messages?)?\.')
def calculate_stats():
localedir = None
if os.path.isdir(os.path.join('conf', 'locale')):
#localedir = os.path.abspath(os.path.join('conf', 'locale'))
localedir = os.path.join('conf', 'locale')
elif os.path.isdir('locale'):
#localedir = os.path.abspath('locale')
localedir = 'locale'
else:
print "This script should be run from the django svn tree or your project or app tree."
print "If you did indeed run it from the svn checkout or your project or application,"
print "maybe you are just missing the conf/locale (in the django tree) or locale (for project"
print "and application) directory?."
sys.exit(1)
(opts, args) = getopt.getopt(sys.argv[1:], 'l:d:va')
lang = None
domain = 'django'
verbose = False
all = False
for o, v in opts:
if o == '-l':
lang = v
elif o == '-d':
domain = v
elif o == '-v':
verbose = True
elif o == '-a':
all = True
if domain not in ('django', 'djangojs'):
print "currently l10n-stats.py only supports domains 'django' and 'djangojs'"
sys.exit(1)
if (lang is None and not all) or domain is None:
print "usage: l10n-stats.py -l <language>"
print " or: l10n-stats.py -a"
sys.exit(1)
languages = []
if lang is not None:
languages.append(lang)
elif all:
languages = [el for el in os.listdir(localedir) if not el.startswith('.')]
if not languages:
sys.exit(0)
workdir = mkdtemp()
potfile = os.path.join(workdir, '%s.pot' % domain)
if os.path.exists(potfile):
os.unlink(potfile)
for (dirpath, dirnames, filenames) in os.walk("."):
for file in filenames:
if domain == 'djangojs' and file.endswith('.js'):
if verbose: sys.stdout.write('processing file %s in %s\n' % (file, dirpath))
data = open(os.path.join(dirpath, file), "rb").read()
data = pythonize_re.sub('\n#', data)
thefile = '%s.py' % file
open(os.path.join(dirpath, thefile), "wb").write(data)
cmd = 'xgettext %s -d %s -L Perl --keyword=gettext_noop --keyword=gettext_lazy --keyword=ngettext_lazy:1,2 --from-code UTF-8 -o - "%s"' % (
os.path.exists(potfile) and '--omit-header' or '', domain, os.path.join(dirpath, thefile))
(stdin, stdout, stderr) = os.popen3(cmd, 't')
msgs = stdout.read()
errors = stderr.read()
if errors:
sys.stderr.write('errors happened while running xgettext on %s\n' % file)
sys.stderr.write(errors)
rmtree(workdir, True)
sys.exit(8)
if msgs:
open(potfile, 'ab').write(msgs)
os.unlink(os.path.join(dirpath, thefile))
elif domain == 'django' and (file.endswith('.py') or file.endswith('.html')):
thefile = file
litfile = os.path.join(dirpath, file)
if file.endswith('.html'):
data = open(litfile, "rb").read()
thefile = '%s.py' % file
litdir = os.path.join(workdir, dirpath)
if not os.path.isdir(litdir):
os.makedirs(litdir)
litfile = os.path.join(litdir, thefile)
open(litfile, "wb").write(templatize(data))
if verbose:
sys.stdout.write('processing file %s in %s\n' % (file, dirpath))
cmd = 'xgettext -d %s -L Python --keyword=gettext_noop --keyword=gettext_lazy --keyword=ngettext_lazy:1,2 --keyword=ugettext_noop --keyword=ugettext_lazy --keyword=ungettext_lazy:1,2 --from-code UTF-8 -o - "%s"' % (
domain, litfile)
(stdin, stdout, stderr) = os.popen3(cmd, 't')
msgs = stdout.read()
errors = stderr.read()
if errors:
sys.stderr.write('errors happened while running xgettext on %s\n' % file)
sys.stderr.write(errors)
rmtree(workdir, True)
sys.exit(8)
if os.path.exists(potfile):
# Strip the header
msgs = '\n'.join(dropwhile(len, msgs.split('\n')))
else:
msgs = msgs.replace('charset=CHARSET', 'charset=UTF-8')
if msgs:
open(potfile, 'ab').write(msgs)
if os.path.exists(potfile):
(stdin, stdout, stderr) = os.popen3('msguniq --to-code=utf-8 "%s"' % potfile, 'b')
pot_msgs = stdout.read()
errors = stderr.read()
if errors:
sys.stderr.write('errors happened while running msguniqi\n')
sys.stderr.write(errors)
rmtree(workdir, True)
sys.exit(8)
open(potfile, 'w').write(pot_msgs)
else:
sys.exit(0)
for lang in languages:
basedir = os.path.join(localedir, lang, 'LC_MESSAGES')
if not os.path.isdir(basedir):
continue
dstdir = os.path.join(workdir, basedir)
if not os.path.isdir(dstdir):
os.makedirs(dstdir)
pofile = os.path.join(basedir, '%s.po' % domain)
dstfile = os.path.join(dstdir, '%s.po' % domain)
if os.path.exists(pofile):
(stdin, stdout, stderr) = os.popen3('msgmerge -q "%s" "%s"' % (pofile, potfile), 'b')
msgs = stdout.read()
errors = stderr.read()
if errors:
sys.stderr.write('errors happened while running msgmerge\n')
sys.stderr.write(errors)
rmtree(workdir, True)
sys.exit(8)
open(dstfile, 'wb').write(msgs)
else:
open(dstfile, 'wb').write(pot_msgs)
(stdin, stdout, stderr) = os.popen3('LC_ALL=C msgfmt --statistics -o - "%s"' % dstfile, 't')
dummy = stdout.read()
data = stderr.read()
mo = msgfmt_re.match(data)
if mo:
groups = mo.groupdict('0')
transl = int(groups['transl'])
fuzzy = int(groups['fuzzy'])
untransl = int(groups['untransl'])
total = transl + fuzzy + untransl
print("%s: translated: %d%%, fuzzy: %d%%, untranslated: %d%%" % (lang, transl*100/total, fuzzy*100/total, untransl*100/total))
#os.unlink(potfile)
#os.rmdir(workdir)
rmtree(workdir, True)
if __name__ == "__main__":
calculate_stats()
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__label__pos
| 0.908417 |
Tcp/Ip Question:
Download Questions PDF
Tell us about a suggestion you have made that has benefited an organization you've worked for?
Answers:
Answer #1
This is another opportunity to show the interviewer what you're capable of so make sure to be prepared for this type of question. Have an example ready and make sure its an example of a suggestion you've made that was accepted and that have positive influence. If you can come up with an example that relates to the position you're applying for that would be even better.
Download Tcp/Ip Interview Questions And Answers PDF
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What did you like least about your last (or current) job Regarding Tcp/Ip?What is your dream job?
|
__label__pos
| 0.951552 |
math
In each set of shapes there is one shape that does not belong tell why
1. 👍 0
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3. 👁 43
asked by kim
1. We don't know what shapes you're seeing.
Respond to this Question
First Name
Your Response
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|
__label__pos
| 0.916224 |
MathMLToBoxes
Same functionality now provided by ImportString[string,{"MathML","Boxes"}].
MathMLToBoxes[string]
converts the string containing MathML-flavored XML text into a Wolfram Language box expression.
DetailsDetails
ExamplesExamplesopen allclose all
Basic Examples (1)Basic Examples (1)
In[1]:=
Click for copyable input
Generate some MathML data using BoxesToMathML:
In[2]:=
Click for copyable input
Out[2]=
Convert the output back into a box expression using :
In[3]:=
Click for copyable input
Out[3]=
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elec_distance_testscript
elec_distance_testscript - dist = sqrt ( xd^2 + yd^2 + zd^2...
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% elec_distance_testscript - test electrode distance calculations elec_labels = cellstr(['a' 'b']'); x = [ 2 -2]'; y = [ 3 2]'; z = [ 2 0]'; xd = x(1) - x(2); yd = y(1) - y(2); zd = z(1) - z(2);
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Unformatted text preview: dist = sqrt ( xd^2 + yd^2 + zd^2 ); fprintf('Cartesian distance = %6.4f\n', dist); [labels, dist] = elec_distance(elec_labels,x,y,z); fprintf('Spherical arc length = %6.4f\n', dist(2,1));...
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Go4Expert
Go4Expert (http://www.go4expert.com/)
- C (http://www.go4expert.com/forums/c/)
- - help :D (http://www.go4expert.com/forums/help-d-t18717/)
cooop 28Jul2009 01:09
help :D
2. Write a C++ program that reads data from an input file called “Input.txt” and counts how many times the file contained words that are the same as their inverse. Such words are called e. The input file can be downloaded from the BB. The program should print the number of palindromes found in the text on the screen, and also saves a copy of each palindrome found in the input file in another file (output file) called “palindromes.txt”.
is this true ? ;D
Code:
#include <iostream>
#include <fstream>
#include <string>
#include <iomanip>
using namespace std;
ifstream fin;
ofstream fout;
bool PalindromeChecker(string inputString)
{
int i=0;
int length = inputString.length();
char temp[255] = {'\0'};
for (i=0; i<length; i++)
{
if ((temp[i] >= 'a') && (temp[i] <= 'z'))
temp[i] = char(int(temp[i]) - 32);
}
for (i=0; i<length; i++)
{
if ((temp[i] < 'A') || (temp[i] > 'Z'))
{
for (int j=i; j<length; j++)
{
temp[j] = temp[j+1];
}
i--;
length--;
}
}
int checkLength = length - 1;
if ((checkLength == 0) || (checkLength == 1))
return true;
for (i=0; i<=checkLength/2; i++)
{
if (temp[i] != temp[checkLength-i])
return false;
}
return true;
}
void printAnswer(string input, bool isit)
{
if (isit == true)
cout << input.data() << " is a palindrome." << endl;
else
cout << input.data() << " is not a palindrome." << endl;
}
int main()
{
string inputString;
bool isPalindrome = true;
fin.open("palindromes.txt");
fout.open("output.txt");
if (!fin.good())
throw "I/O Error!";
if (!fout.good())
throw "I/O Error!";
while (fin.good())
{
getline(fin,inputString);
isPalindrome = PalindromeChecker(inputString);
printAnswer(inputString,isPalindrome);
}
fin.close();
fout.close();
return 0;
}
xpi0t0s 28Jul2009 02:19
Re: help :D
Please use code blocks when you post code. You've been around long enough now to know about them. It makes code easier to read by preserving the formatting and using a fixed pitch font.
Rather than me reading the code and trying to figure out if it's correct or not, why don't you plug it into your favourite compiler, write some test data and see what the program does with that data. If it picks out the right data and ignores the wrong, then it works. If it doesn't, then it doesn't.
If you display the contents of temp just before returning from PalindromeChecker(), passing in some known words, does temp contain what you expect?
xpi0t0s 28Jul2009 23:21
Re: help :D
tried the code in Visual Studio 2008. Reduced the code to:
Code:
char *str="HellolleH";
printf("%s %s a palindrome\n",str,PalindromeChecker(str)?"IS":"IS NOT");
and it (wrongly) said IS NOT. Have a look at the code in the PalindromeChecker function and tell me what you think the first for() loop will do. Will that "if" ever evaluate true?
All times are GMT +5.5. The time now is 23:15.
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Calcular el factorial de 130 (¡130!)
¿Cuánto es el factorial 130?
El resultado de 130 factorial se muestra en el campo de abajo. Si desea realizar otro cálculo, ingrese un valor entre 0 y 500 en el campo a continuación y presione calcular:
=
¿Cuál es la fórmula para calcular el factorial 130?
El cálculo se realiza de la siguiente manera: 130! = 130 * ... * 40 * 39 * 38 * 37 * 36 * 35 * 34 * 33 * 32 * 31 * 30 * 29 * 28 * 27 * 26 * 25 * 24 * 23 * 22 * 21 * 20 * 19 * 18 * 17 * 16 * 15 * 14 * 13 * 12 * 11 * 10 * 9 * 8 * 7 * 6 * 5 * 4 * 3 * 2 * 1 = 6466855489220473672507...
¿Cuántos dígitos tiene el factorial 130?
La cantidad de dígitos de 130! Su: 220
¿Cuántos ceros hay al final del factorial de 130?
¡El número de ceros después de 130! Su: 32
Tabla de Factores del 1 al 25
Factorial Resultado
1!1
2!2
3!6
4!24
5!120
6!720
7!5040
8!40320
9!362880
10!3628800
11!39916800
12!479001600
13!6227020800
14!87178297200
15!1307674368000
16!20922789888000
17!355687428096000
18!6402373705728000
19!121645100408832000
20!2432902008176640000
21!51090942171709440000
22!1124000727777607680000
23!25852016738884976640000
24!620448401733239439360000
25!15511210043330985984000000
Otros números factoriales
|
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| 0.962546 |
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Can You Trust Your Tests? (Agile Tour 2015 Kaunas)
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Nobody argues these days that unit tests are useful and provide valuable feedback about your code. But who watches the watchmen? Let's talk about test code quality, code coverage and introduce mutation based testing techniques.
Published in: Software
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Can You Trust Your Tests? (Agile Tour 2015 Kaunas)
1. 1. Can You Trust Your Tests? 2015 Vaidas Pilkauskas & Tadas Ščerbinskas
2. 2. Van Halen
3. 3. Band Tour Rider
4. 4. Van Halen’s 1982 Tour Rider
5. 5. Agenda 1. Test quality & code coverage 2. Mutation testing in theory 3. Mutation testing in practice
6. 6. Prod vs. Test code quality Code has bugs. Tests are code. Tests have bugs.
7. 7. Test quality Readable Focused Concise Well named
8. 8. “Program testing can be used to show the presence of bugs, but never to show their absence!” - Edsger W. Dijkstra
9. 9. Code Coverage
10. 10. Types of Code Coverage Lines Branches Instructions Cyclomatic Complexity Methods & more
11. 11. Lines string foo() { return "a" + "b" } assertThat(a.foo(), is("ab"))
12. 12. Lines string foo(boolean arg) { return arg ? "a" : "b" } assertThat(a.foo(true), is("a"))
13. 13. Branches string foo(boolean arg) { return arg ? "a" : "b" } assertThat(a.foo(true), is("a")) assertThat(a.foo(false), is("b"))
14. 14. SUCCESS: 26/26 (100%) Tests passed
15. 15. Can you trust 100% coverage? Code coverage can only show what is not tested. For interpreted languages 100% code coverage is kind of like full compilation.
16. 16. Code Coverage can be gamed On purpose or by accident
17. 17. Mutation testing
18. 18. Mutation testing Changes your program code and expects your tests to fail.
19. 19. What exactly is a mutation? def isFoo(a) { return a == foo } def isFoo(a) { return a != foo } def isFoo(a) { return true } def isFoo(a) { return null } > > >
20. 20. Terminology Applying a mutation to some code creates a mutant. If test passes - mutant has survived. If test fails - mutant is killed.
21. 21. Failing is the new passing
22. 22. array = [a, b, c] max(array) == ???
23. 23. // test max([0]) == 0 ✘
24. 24. // test max([0]) == 0 ✔ // implementation max(a) { return 0 }
25. 25. // test max([0]) == 0 ✔ max([1]) == 1 ✘ // implementation max(a) { return 0 }
26. 26. // test max([0]) == 0 ✔ max([1]) == 1 ✔ // implementation max(a) { return a.first }
27. 27. // test max([0]) == 0 ✔ max([1]) == 1 ✔ max([0, 2]) == 2 ✘ // implementation max(a) { return a.first }
28. 28. // test max([0]) == 0 ✔ max([1]) == 1 ✔ max([0, 2]) == 2 ✔ // implementation max(a) { m = a.first for (e in a) if (e > m) m = e return m }
29. 29. Coverage
30. 30. Mutation // test max([0]) == 0 ✔ max([1]) == 1 ✔ max([0, 2]) == 2 ✔ // implementation max(a) { m = a.first for (e in a) if (e > m) m = e return m }
31. 31. Mutation // test max([0]) == 0 ✔ max([1]) == 1 ✔ max([0, 2]) == 2 ✔ // implementation max(a) { m = a.first for (e in a) if (true) m = e return m }
32. 32. // test max([0]) == 0 ✔ max([1]) == 1 ✔ max([0, 2]) == 2 ✔ // implementation max(a) { return a.last }
33. 33. // test max([0]) == 0 ✔ max([1]) == 1 ✔ max([0, 2]) == 2 ✔ max([2, 1]) == 2 ✘ // implementation max(a) { return a.last }
34. 34. // implementation max(a) { m = a.first for (e in a) if (e > m) m = e return m } // test max([0]) == 0 ✔ max([1]) == 1 ✔ max([0, 2]) == 2 ✔ max([2, 1]) == 2 ✔
35. 35. Baby steps matter
36. 36. Tests’ effectiveness is measured by number of killed mutants by your test suite.
37. 37. It’s like hiring a white-hat hacker to try to break into your server and making sure you detect it.
38. 38. What if mutant survives ● Simplify your code ● Add additional tests ● TDD - minimal amount of code to pass the test
39. 39. Challenges 1. High computation cost - slow 2. Equivalent mutants - false negatives 3. Infinite loops
40. 40. Equivalent mutations // Original int i = 0; while (i != 10) { doSomething(); i += 1; } // Mutant int i = 0; while (i < 10) { doSomething(); i += 1; }
41. 41. Infinite Runtime // Original while (expression) doSomething(); // Mutant while (true) doSomething();
42. 42. Disadvantages ● Can slow down your TDD rhythm ● May be very noisy
43. 43. Let’s say we have codebase with: ● 300 classes ● around 10 tests per class ● 1 test runs around 1ms ● total test suite runtime is about 3s Is it really slow? Let’s do 10 mutations per class ● We get 3000 (300 * 10) mutations ● runtime with all mutations is 150 minutes (3s * 3000)
44. 44. Speeding it up Run only tests that cover the mutation ● 300 classes ● 10 tests per class ● 10 mutations per class ● 1ms test runtime ● total mutation runtime 10 * 10 * 1 * 300 = 30s
45. 45. Speeding it up During development run tests that cover only your current changes
46. 46. ● Continuous integration ● TDD with mutation testing only on new changes ● Add mutation testing to your legacy project, but do not fail a build - produce warning report Usage scenarios
47. 47. Tools ● Ruby - Mutant ● Java - PIT ● And many tools for other languages
48. 48. Summary ● Code coverage highlights code that is definitely not tested ● Mutation testing highlights code that definitely is tested ● Given non equivalent mutations, good test suite should work the same as a hash function
49. 49. Vaidas Pilkauskas @liucijus ● Vilnius JUG co-founder ● Vilnius Scala leader ● Coderetreat facilitator ● Mountain bicycle rider ● Snowboarder About us Tadas Ščerbinskas @tadassce ● VilniusRB co-organizer ● RubyConfLT co- organizer ● RailsGirls Vilnius & Berlin coach ● Various board sports’ enthusiast
50. 50. Credits A lot of presentation content is based on work by these guys ● Markus Schirp - author of Mutant ● Henry Coles - author of PIT ● Filip Van Laenen - working on a book
51. 51. Q&A
×
|
__label__pos
| 0.951131 |
Matplotlib: как построить категориальные данные по оси y?
Предположим, что у меня есть следующий код, который исходит отсюда :
gender = ['male','male','female','male','female'] import matplotlib.pyplot as plt from collections import Counter c = Counter(gender) men = c['male'] women = c['female'] bar_heights = (men, women) x = (1, 2) fig, ax = plt.subplots() width = 0.4 ax.bar(x, bar_heights, width) ax.set_xlim((0, 3)) ax.set_ylim((0, max(men, women)*1.1)) ax.set_xticks([i+width/2 for i in x]) ax.set_xticklabels(['male', 'female']) plt.show()
Каким образом можно было бы строить категории male и female по оси y, в отличие от оси x?
One Solution collect form web for “Matplotlib: как построить категориальные данные по оси y?”
Возможно, вы ищете barh :
gender = ['male','male','female','male','female'] import matplotlib.pyplot as plt from collections import Counter c = Counter(gender) men = c['male'] women = c['female'] bar_heights = (men, women) y = (1, 2) fig, ax = plt.subplots() width = 0.4 ax.barh(y, bar_heights, width) ax.set_ylim((0, 3)) ax.set_xlim((0, max(men, women)*1.1)) ax.set_yticks([i+width/2 for i in y]) ax.set_yticklabels(['male', 'female']) plt.show()
введите описание изображения здесь
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• Matplotlib: размер финальной фигуры соответствует фигуре с savefig () и bbox_extra_artists
• Вращающиеся стрелки приводят к тому, что тики частично скрыты в matplotlib
• Python - лучший язык программирования в мире.
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| 0.980571 |
qq_29217127
2021-07-06 21:26
采纳率: 100%
浏览 29
如何用python找到文件夹中指定格式的最新文件？
比如我的文件夹中有.txt、.mp3、.mp4三种格式的文件，我想找出.mp4文件中的最新文件，请问该如何用python实现这个效果
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• 写回答
• 关注问题
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2条回答 默认 最新
• 宁缺灬 2021-07-07 10:28
已采纳
img
import os,time
rst = dict()
rst['time'] = 0
f_list = os.listdir("./")
for f in f_list:
if os.path.splitext(f)[1] == ".mp4":
t = str(os.path.getctime(f))
t = int(t[:t.find(".")])
print(f,time.strftime("%Y-%m-%d %H:%M:%S",time.localtime(t)))
if rst['time'] < t:
rst['time'] = t
rst['ftime'] = time.strftime("%Y-%m-%d %H:%M:%S",time.localtime(t))
rst['url'] = f
print(rst)
主要还是拿到最后创建的对应格式的文件。最后x个的话就拿个数组把dict都存进去，根据time做排序就行了。
点赞 评论
• 奋斗的小小鱼 2021-07-06 21:57
参考下：
def getFileName(path):
''' 获取指定目录下的所有指定后缀的文件名 '''
f_list = os.listdir(path)
for i in f_list:
if os.path.splitext(i)[1] == '.mp4':
print(i)
if __name__ == '__main__':
path = 'E:\job'
getFileName(path)
点赞 评论
相关推荐 更多相似问题
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__label__pos
| 0.570268 |
What is the output of below Javascript code?
function check_value()
{
var value = new Boolean(false);
alert(String(value));
}
Posted by vishalneeraj-24503 on 12/19/2013 | Category: JavaScript Interview questions | Views: 2229 | Points: 40
Answer:
Output will be "false".
As we know that,Boolean data-type takes only True and False value.
The String() function converts the value of an object to a string. That's why it would be False.
Asked In: Many Interviews | Alert Moderator
Comments or Responses
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1. 首页
2. WordPress钩子手册
do_robots
do_action( ‘do_robots’ )
动作钩子：：当模板加载器确定robots.txt文件请求。
Action Hook: Fired when the template loader determines a robots.txt request.
目录锚点：#源码
源码（Source）
/**
* Display the robots.txt file content.
*
* The echo content should be with usage of the permalinks or for creating the
* robots.txt file.
*
* @since 2.1.0
*/
function do_robots() {
header( 'Content-Type: text/plain; charset=utf-8' );
/**
* Fires when displaying the robots.txt file.
*
* @since 2.1.0
*/
do_action( 'do_robotstxt' );
$output = "User-agent: *
";
$public = get_option( 'blog_public' );
if ( '0' == $public ) {
$output .= "Disallow: /
";
} else {
$site_url = parse_url( site_url() );
$path = ( !empty( $site_url['path'] ) ) ? $site_url['path'] : '';
$output .= "Disallow: $path/wp-admin/
";
}
/**
* Filter the robots.txt output.
*
* @since 3.0.0
*
* @param string $output Robots.txt output.
* @param bool $public Whether the site is considered "public".
*/
echo apply_filters( 'robots_txt', $output, $public );
}
更新版本 源码位置 使用 被使用
2.1.0 wp-includes/template-loader.php:37 0 0
do_robots 为WP2原创文章，链接：https://www.wp2.cn/hook/do_robots/
|
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| 0.983054 |
Is Java Script Really An Object Oriented Language?
There have been a lot of debate over whether or not JavaScript is an Object Oriented Programming language.
After reading a lot of material on this question I have a short answer for you - YES, JavaScript is an OOP language!
Especially when JS-ninjas who are known for their contributions to the language itself, like Douglas Crockford say it, you might want to believe it.
But, it is not a class-based object-oriented language like Java, C++, C#, etc.
Let's go a little deeper into why JavaScript might be an OOP language. And, explore the basics of object-oriented programming (OOP) using JavaScript.
OOP - Basics
So, what makes any programming language Object Oriented? Well, there are various definitions on this but essentially, for any language to be Object Oriented language it has to support following important features at the least:
1. Encapsulation - Object's internal working is hidden from the rest of the application.
2. Inheritance - Object can inherit properties and method from a parent object.
3. Polymorphism - Object can having multiple forms.
So, if we can prove that JavaScript supports all of the above features we can call it an Object Oriented Programming language. Let's see each feature one by one in action using JavaScript.
Creating Objects in JavaScript
In JavaScript, we can easily create objects out of thin air.
For example, let's say we are creating a game and we want to create a player object. We can define the player's name as "Duffy" and the number of lives as 3.
This data is stored in an object, which is essentially a dictionary with keys and values.
const player = {
name: "Duffy",
lives: 3,
};
Tip: We can even represent this object as a JSON string and pass it over an HTTP request.
But objects in JavaScript can also have functions as values. Isn't that cool?
We can add a function called greet to the player object, which will log "Hello" to the console when executed.
const player = {
name: "Duffy",
lives: 3,
greet: function() {
console.log("Hello");
},
};
By executing player.greet(), we can see the output "Hello" in the console.
Encapsulation.
Encapsulation simply means, private data of an Object should not be directly accessible to the outside world. There should be methods to get and to set the internal properties of that object.
First, let's see, what is NOT encapsulation?
var Person = function (){
return {
fullName: "John Doe"
};
};
var user = Person();
console.log(user.fullName); // "John Doe"
user.fullName = "Foo Joe"
Although it is perfectly legal to write the above code, it is not a recommended way to write it that way due to various reasons like the security of the code, its lack of ability to validate the code, and much more.
What Is Encapsulation?
var Person = function (){
var fullName = "John Doe";
return {
getName: function(){
return fullName;
},
setName: function(name){
fullName = name;
}
};
};
var user = Person();
console.log(user.getName()); // "John Doe"
user.setName("Foo Joe");
The above code is encapsulated because the property fullName cannot be accessed from anywhere outside the Person function.
Thus, by the definition of encapsulation we saw above, it is proved that JavaScript supports encapsulation.
Inheritance
This feature gives the ability to an object to inherit functionality and properties from parent objects.
Developers coming from C++/Java background- please be advised that JavaScript supports prototypal inheritance and not the usual classical inheritance.
I will cover what are prototypes and what is prototypal inheritance in future post. But, for now, it simply means that each object in JavaScript serves as a prototype which can be cloned to create another object having similar behavior as the original object in question.
Now, let's look at a very simple example demonstrating prototypal inheritance in JavaScript.
var animal = { sleeps: true };
var tiger = Object.create(animal);
tiger.eats = true;
console.log(tiger.sleeps); // true
console.log(tiger.eats); // true
In the above example, Object.create() is used to create a new object by specifying its prototype object. A "tiger" object was created using "animal" as its prototype. And due to prototypal inheritance, "tiger" object also got "sleeps" property from its parent "animal" object.
Thus, by the definition of prototypal inheritance, it is proved that JavaScript supports inheritance.
Polymorphism.
JavaScript being a dynamic language by nature, it does not support all the classical types of polymorphism like function overloading or parametric based polymorphism. But, based on the kind of inheritance it exhibits, JavaScript supports subtype polymorphism which is very popular in even class-based languages like Java/C++.
Continuing the same example we saw in inheritance, let's see how polymorphism can be implemented in JavaScript.
var animal = {
sleeps: true,
getInfo: function(){
return "I am animal";
}
};
"animal" is a base object. Let's inherit "lion" and "tiger" objects from "animal".
var lion = Object.create(animal);
var tiger = Object.create(animal);
tiger.getInfo = function(){
return "I am tiger";
};
We used Object.create() method to inherit "lion" and "tiger" objects from "animal". Then for the "tiger" object we overrode the getInfo function to be more specific to that object. But, we did not do the same for the "lion" object.
Now, let's see what happens when getInfo function is called on both the objects.
console.log(lion.getInfo()); // "I am animal"
console.log(tiger.getInfo()); // "I am tiger"
As we did not override getInfo function for "lion" object it uses the getInfo function of its parent, that is, "animal" object. On the other hand, we wrote a specific getInfo function for the "tiger" object hence when the getInfo was executed on it, it executed the specific function to that object instead of the getInfo function of its parent Animal object.
The getInfo function is resolved at runtime, and this is called late binding or dynamic Polymorphism.
Thus, it is proved that JavaScript supports polymorphism.
Final Thoughts
Based on above examples, we can definitely say that, although different from class-based languages, JavaScript is also an Object Oriented Programming language. Remember, everything in Javascript is an object, compared to C++ or Java.
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Introduction to Python
Prep Work
• download anaconda from the link belwo
https://www.anaconda.com/download/#windows
Open it with Anaconda Prompt
create a new environment，克隆一个基础环境
conda create --name hello --clone base
• download Pycharm
• create a new project in pycharm using the environment above
Basic Language
1. Reserved Keywords
Although Python will not stop you, do not use these as variable or function names.
and del from not while
as elif global or with
assert else if pass yield
break except import print
class exec in raise
continue finally is return
def for lambda try
or these other
abs all any apply basestring bin bool buffer bytearray bytes callable chr classmethod cmp coerce compile complex delattr dict dir divmod enumerate eval execfile file filter float format frozenset getattr globals hasattr hash hex id input int intern isinstance issubclass iter len list locals long map max min next object oct open ord pow print property range raw_input reduce reload repr reversed round set setattr slice sorted staticmethod str sum super tuple type unichr unicode vars xrange zip
2. Numbers
Python has common‑sense number‑handling capabilities.
>>> 2+2
4
>>> 2+2 # and a comment on the same line as code
4
>>> (50‑5*6)/4
5
>>> 7/3 # Integer division returns the floor:
2
>>> 7/‑3 # ext integer down
‑3
>>> width = 20
>>> height = 5*9
>>> width * height
>>> x = y = z = 0 # Zero x, y and z
>>> x
0
>>> y
0
>>> z
0
>>> 3 * 3.75 / 1.5
7.5
>>> 7.0 / 2 # float numerator
3.5
>>> from __future__ import division # no more default integer division!
>>> 7/2
3.5
>>> 7 // 2 # double slash gives integer division
3
You can also cast among the numeric types in a common‑sense way:
>>> int(1.33333)
1
>>> float(1)
1.0
>>> type(1)
int
>>> type(float(1))
float
3. Complex Numbers
Python has rudimentary support for complex numbers.
>>> 1j * 1J
(‑1+0j)
>>> 1j * complex(0,1)
(‑1+0j)
>>> 3+1j*3
(3+3j)
>>> (3+1j)*3
(9+3j)
>>> (1+2j)/(1+1j)
(1.5+0.5j)
>>> a=1.5+0.5j
>>> a.real # the dot notation gets an attribute
1.5
>>> a.imag
0.5
>>> a=3.0+4.0j
>>> float(a)
Traceback (most recent call last):
File "<stdin>", line 1, in ?
TypeError: can't convert complex to float; use abs(z)
>>> a.real
3.0
>>> a.imag
4.0
>>> abs(a) # sqrt(a.real**2 + a.imag**2)
5.0
>>> tax = 12.5 / 100
>>> price = 100.50
>>> price * tax
12.5625
>>> price + _
113.0625
>>> round(_, 2)
113.06
4. Strings
String‑handling is very well developed and highly optimized in Python. We just cover the main points here. First, single or double quotes define a string and there is no precedence relationship between sin‑ gle and double quotes.
>>> 'spam eggs'
'spam eggs'
>>> 'doesn\'t'
"doesn't"
>>> "doesn't"
"doesn't"
>>> '"Yes," he said.'
'"Yes," he said.'
>>> "\"Yes,\" he said."
'"Yes," he said.'
>>> '"Isn\'t," she said.'
'"Isn\'t," she said.'
Python strings have C‑style escape characters for newlinews, tabs, etc.
>>> print """Usage: thingy [OPTIONS]
‑h Display this usage message
‑H hostname Hostname to connect to
"""
>>> # the 'r' makes this a 'raw' string
>>> hello = r"This is a rather long string containing\n\ several lines of text much as you w
>>> print hello
This is a rather long string containing\n\ several lines of text much as you would do in C.
>>> # otherwise, you get the newline \n
>>> hello = "This is a rather long string containing\n\ several lines of text much as you wo
>>> print hello
This is a rather long string containing
several lines of text much as you would do in C.
>>> u'this a unicode string µ ±' # the 'u' makes it a unicode string
>>> u'this a unicode string \xb5 \xb1' # using hex‑codes
5. Slicing Strings
Python is a zero‑indexed language (like C). The color : character denotes slicing.
>>> word = 'Help' + 'A'
>>> word
'HelpA'
>>> '<' + word*5 + '>'
'<HelpAHelpAHelpAHelpAHelpA>'
>>> word[4]
'A'
>>> word[0:2]
'He'
>>> word[2:4]
'lp'
>>> word[‑1] # The last character
'A'
>>> word[‑2] # The last‑but‑one character
'p'
>>> word[‑2:] # The last two characters
'pA'
>>> word[:‑2] # Everything except the last two characters
'Hel'
>>> word[0] = 'Q' # strings are IMMUTABLE
Traceback (most recent call last):
...
TypeError: 'str' object does not support item assignment
6. String Operations
Some basic numerical operations work with strings.
>>> 'hey '+'you' # concatenate with plus operator
'hey you'
>>> 'hey '*3 # multiply duplicates strings
'hey hey hey '
Python has a built‑in and very powerful regular expression module for string manipulations.
7. Substitutions
String substitution creates new strings.
>>> x = 'This is a string'
>>> print x.replace('string','newstring')
This is a newstring
>>> print x # x hasn't changed
This is a string
8. Formatting Strings
There are so many ways to format strings in Python, but here is the simplest that follows C‑language sprintf conventions in conjunction with the modulo operator %.
>>> print 'this is a decimal number %d' % ( 10 )
this is a decimal number 10
>>> print 'this is a float %3.2f' % (10.33)
this is a float 10.33
>>> x = 1.03
>>> print 'this is a variable %e' % (x) # exponential format
this is a variable 1.030000e+00
Basic Data Structures
Python provides many powerful data structures. The two most powerful and fundamental are the list and dictionary. We have already seen that strings are immutable. Python also provides immutable data structures.
1. Lists – generalized containers (mutable)
The list is an order‑preserving general container.
>>> mix=[3,'tree',5.678,[8,4,2]]; mix # List creation
[3, 'tree', 5.6779999999999999, [8, 4, 2]]
>>> mix[1] # Indexing individual elements
'tree'
>>> mix[0]
3
>>> mix[‑2] # Indexing from the right
5.6779999999999999
>>> mix[3]
[8, 4, 2]
>>> mix[3][1] # Last element is itself a list
4
>>> mix[0]=666; mix # Mutable
[666, 'tree', 5.6779999999999999, [8, 4, 2]]
>>> submix=mix[0:3]; submix # Creating sublist
[666, 'tree', 5.6779999999999999]
>>> switch=mix[3]+submix; switch # + Operator
[8, 4, 2, 666, 'tree', 5.6779999999999999]
>>> len(switch) # Built‑in Function
6
>>> resize=[6.45,'SOFIA',3,8.2E6,15,14]; len(resize)
6
>>> resize[1:4]=[55]; resize; len(resize) # Shrink a sublist
[6.4500000000000002, 55, 15, 14]
4
>>> resize[3]=['all','for','one']; resize; len(resize)
[6.4500000000000002, 55, 15, ['all', 'for', 'one']]
4
>>> resize[4]=2.87 # Cannot append this way
Traceback (most recent call last):
...
IndexError: list assignment index out of range
>>> temp=resize[:3]
>>> resize=temp+resize[3]; resize; len(resize) # add to list
[6.4500000000000002, 55, 15, 'all', 'for', 'one']
6
>>> del resize[3]; resize; len(resize) # delete an element
[6.4500000000000002, 55, 15, 'for', 'one']
5
>>> del resize[1:3]; resize; len(resize) # delete a sublist
[6.4500000000000002, 'for', 'one']
3
• # Sorting lists
>>> sorted([1,9,8,2]) # this sorts lists
[1, 2, 8, 9]
2. Tuples – containers (immutable)
Tuples are another general purpose sequential container in Python, very similar to lists, but these are immutable. Tuples are delimited by commas (parentheses are grouping symbols).
>>> tuple([1,3,4])
(1, 3, 4)
>>> 1,3,4
(1, 3, 4)
>>> pets=('dog','cat','bird') #Parentheses () create tuples
>>> pets[0]
'dog'
>>> pets + pets # addition
('dog', 'cat', 'bird', 'dog', 'cat', 'bird')
>>> pets*3
('dog', 'cat', 'bird', 'dog', 'cat', 'bird', 'dog', 'cat', 'bird')
>>> pets[0]='rat' # assignment not work!
TypeError: 'tuple' object does not support item assignment
3. Key Concept: Mutable vs. Immutable
In Python, the easiest way to think of variables is in terms of immutable (not changeable) or mutable (changeable).
>>> x = [1,3,4,['one',1.33]] # lists are a mutable (i.e. changeable)
>>> x[0]='banana' # no problem changing this
>>> y = (1,3,4,['one',1.33]) # tuples are a immutable (i.e. not changeable)
>>> y[0]='banana'
Traceback (most recent call last):
...
TypeError: 'tuple' object does not support item assignment
>>> z=('banana',)+y[1:] # I need to make a new tuple to change it
>>> print id(y)
25690000
>>> print id(z)
26030320
>>> print id(x)
26055664
>>> x[1]='here I go again' # make a change (okay!)
>>> print id(x)
26055664
4. Dictionaries – The MOST IMPORTANT Python data structure
>>> top={'math':'Gauss','phys':'Newton','art':'Vemeer','phil':'Emerson',
... 'play':'Shakespeare','actor':'Kidman','direct':'Kubrick',
... 'author':'Hemmingway','bio':'Watson','group':'R.E.M'}
...
>>> len(top) #{ } are dictionary creation operators
10
>>> top['pres']='F.D.R.'
>>> top['bio']='Darwin'
>>> #can delete a key,value pair
>>> del top['actor']
>>> # another way of creating a dict
>>> x=dict(key='value',another_key=1.333,more_keys=[1,3,4,'one'])
>>> print x
{'another_key': 1.333, 'more_keys': [1, 3, 4, 'one'], 'key': 'value'}
>>> x={(1,3):'value'} # any immutable type can be a valid key
>>> print x
{(1, 3): 'value'}
>>> x[(1,3)]='immutables can be keys'
What if you want to create a union of dictionaries in one‑line?
>>> d1 = {'a':1, 'b':2, 'c':3}
>>> d2 = {'A':1, 'B':2, 'C':3}
>>> dict(d1,**d2) # combo of d1 and d2
{'A': 1, 'B': 2, 'C': 3, 'a': 1, 'b': 2, 'c': 3}
5. Sets
Python provides mathematical sets and corresponding operations with the set() data structure.
>>> print set([1,2,11,1]) # union‑izes elements
set([1, 2, 11])
>>> print set([1,2,3]) & set([2,3,4]) # intersection
set([2, 3])
>>> print set([1,2,3]) and set([2,3,4]) # not work
set([2, 3, 4])
>>> print set([1,2,3]) ^ set([2,3,4]) # exclusive OR
set([1, 4])
>>> print set([1,2,3]) | set([2,3,4]) # OR
set([1, 2, 3, 4])
>>> print set([ [1,2,3],[2,3,4] ]) # no sets of lists (w/o more work)
Traceback (most recent call last):
TypeError: unhashable type: 'list'
Basic Programming
1. Loops and Conditionals
There are two primary looping constructs in Python: the for loop and the while loop. The syntax of the for loop is straightforward:
>>> for i in range(3):
... print i
Note the colon character at the end. This is your hint that the next line should be indented. The for loop iterates over items that provided by the iterator, which is the range(3) list in the above example. Python abstracts the idea of iterable out of the looping construction so that some Python objects are iterable all by themselves and are just waiting for an iteration provider like a for or while loop to get them going.
The while loop has a similar straightforward construct:
>>> i = 0
>>> while i < 10:
... i += 1
...
Again, note that the presence of the colon character hints at indenting the following line. The while loop will continue until the boolean expression (i.e., i<10) evaluates False. Let’s consider booleans and mem‑ bership in Python.
2. Logic and Membership
Python is a truthy language:
Only these are false:
• None
• False
• zero of any numeric type, for example, 0, 0L, 0.0, 0j.
• any empty sequence, for example, '', (), [].
• any empty mapping, for example, {}.
• instances of user‑defined classes, if the class defines a nonzero() or len() method, when that method returns the integer zero or bool value False.
>>> bool(1)
True
>>> bool([]) # empty list
False
>>> bool({}) # empty dictionary
False
>>> bool(0)
False
>>> bool([0,])
True
Python is syntactically clean about numeric intervals!
>>> 3.2 < 10 < 20
True
You can use disjunctions (or), negations (not), and conjunctions (and) also.
>>> 1 < 2 and 2 < 3 or 3 < 1
True
>>> 1 < 2 and not 2 > 3 or 1<3
True
It’s advisable to use grouping parentheses for readability. You can use logic across iterables as in the following:
>>> (1,2,3) < (4,5,6) # at least one True
True
>>> (1,2,3) < (4,5,1) # logical disjunction across elements
True
I’ve never seen this idiom in the wild, though. Don’t use relative comparison for Python strings (i.e., 'a'< 'b'). It gets weird like that. Use string matching operations instead (i.e., ==).
Membership testing uses the in keyword.
>>> 'on' in [22,['one','too','throw']]
False
>>> 'one' in [22,['one','too','throw']] # no recursion
False
>>> 'one' in [22,'one',['too','throw']]
True
>>> ['too','throw'] not in [22,'one',['too','throw']]
False
If you are testing membership across millions of elements it is much faster to use set() instead of list. For example,
>>> 'one' in {'one','two','three'}
>>> 'one' in set(['one','two','three'])
The is keyword is stronger than equality, because it checks if two objects are the same
>>> x = 'this string'
>>> y = 'this string'
>>> print x is y
False
>>> print x==y
True
However, is is really checking the id of each of the items:
>>> x=y='this string'
>>> print id(x),id(y)
4281928416 4281928416
>>> print x is y
True
By virtue of this, the following idioms are common:
x is True, x is None.
3. Conditonals
Now that we understand boolean expressions, we can build conditional statements using if.
>>> if 1 < 2:
... print 'one less than two'
There is an else and elif, but no switch statement.
>>> a = 10
>>> if a < 10:
... print 'a less than 10'
... elif a < 20:
... print 'a less than 20'
... else:
... print 'a otherwise'
There is a one‑liner for conditionals
>>> x = 1 if (1>2) else 3 # 1‑line conditional
>>> print x
3
The for loop can have an else clause as in the following
>>> rangelist = range(10)
>>> print rangelist
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
>>> for number in rangelist:
... # Check if number is one of
... # the numbers in the tuple.
... if number in (3, 4, 7, 9):
... # "Break" terminates a for without
... # executing the "else" clause.
... break
... else:
... # "Continue" starts the next iteration
... # of the loop. It's rather useless here,
... # as it's the last statement of the loop.
... continue
... else:
... # The "else" clause is optional and is
... # executed only if the loop didn't "break".
... pass # Do nothing
This is good for recognizing when a loop exits normally or via break.
4. List Comprehensions
Collecting items over a loop is common that it is its own idiom in Python. That is,
>>> out=[] # initialize container
>>> for i in range(10): out.append(i**2)
>>> out
[0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
This can be abbreviated as a list comprehension.
>>> [i**2 for i in range(10)]
[0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
Conditional elements can be embedded in the list comprehension.
>>> [i**2 for i in range(10) if i % 2] # embedded conditional
[1, 9, 25, 49, 81]
These comprehensions also works as dictionaries and sets.
>>> {i:i**2 for i in range(5)}
{0: 0, 1: 1, 2: 4, 3: 9, 4: 16}
>>> {i**2 for i in range(5)}
{0, 1, 4, 9, 16}
5. Functions
There are two common ways to define functions. You can use the def keyword as in the following:
>>> def foo(): return 'I said foo'
>>> foo()
'I said foo'
Note that you need a return statement and that you need the parenthesis to actually invoke the func‑ tion. Without the return statement, the functions returns the None singleton.
Functions are first‑class objects.
>>> foo # just another Python object
<function __main__.foo>
Practically speaking, this means they can be manipulated like any other Python object — they can be put in containers and passed around without any special handling. Naturally, we want to supply arguments to our functions. There are two kinds of function arguments positional and keyword.
>>> def foo(x): # positional unnamed argument
... return x*2
...
>>> foo(10)
20
Keyword arguments allow you to specify defaults.
>>> def foo(x=20): # keyword named argument
... return 2*x
...
>>> foo(1)
2
>>> foo()
40
>>> foo(x=30)
60
>>>
>>> def foo(x=20,y=30):
... return x+y
...
>>> foo(20,)
50
>>> foo(1,1)
2
>>> foo(y=12)
32
>>> help(foo)
Help on function foo in module __main__:
...
foo(x=20, y=30) # provides automatic documentation
Python makes it easy to include documentation for your functions using docstrings. The makes the help function more useful for functions.
>>> def foo(position=20,velocity=30): #using a documentation string docstring
... '''position in m
... velocity in m/s
... '''
... return x+y
>>> help(foo)
Help on function foo in module __main__:
...
foo(position=20, velocity=30)
position in m
velocity in m/s
Thus, by using meaningful argument and function names and including basic documentation in the docstrings, you can greatly improve the usability of your Python functions. Also, it is recommended to make function names verb‑like (e.g., get_this, compute_field ) In addition to using the def statement, you can also create functions using lambda. These are sometimes called anonymous functions.
>>> f = lambda x: x**2 # anonymous functions
>>> f(10)
100
>>> [lambda x: x, lambda x:x**2] # list of functions
[<function <lambda> at ...>, <function <lambda> at ...>]
>>> for i in _:
... print i(10)
10
100
So far, we have not made good use of tuple, but these data structures become very powerful when used with functions. This is because they allow you to separate the function arguments (i.e., function signa‑ ture) from the function itself. This means you can pass them around and build function arguments and then later execute them with one or more functions.
The usefulness of tuples derives from using them with functions
>>> args = (1,3,4)
>>> def foo(x,y,z): #defining
... return x+y+z
>>> print foo(*args) # note the asterisk notation
8
This also works with keyword arguments
>>> def foo(x=1,y=2,z=3):
... return x+y+z
>>> kwargs = {'x':10,'y':20,'z':30}
>>> print foo(**kwargs) # note the double asterisks
60
>>> kwargs = {'x':10,'y':20,'z':30,'h':100} # extra argument
>>> print foo(**kwargs) # note the double asterisks
Traceback (most recent call last):
...
TypeError: foo() got an unexpected keyword argument 'h'
This also works in combination
>>> def foo(x,y=2,z=3): # note the the first argument is positional
... return x+y+z
>>> kwargs = {'y':20,'z':30}
>>> args = (1,)
>>> foo(*args,**kwargs)
51
6. Function Variable Scoping
Variables within functions or subfunctions are local to that respective scope. Global variables require special handling if they are going to be changed inside the function body.
>>> x=10 # outside function
>>> def foo():
... return x
>>> def foo():
... x=1 # defined inside function
... return x
>>> def foo():
... global x # define as global
... x=20 # assign inside function scope
... return x
>>> print x
10
7. Function keyword filtering
Using **kwds at the end allows functions to disregard keywords they don’t use while filtering out (using the function signature) the keyword inputs that it does use.
def foo(x=1,y=2,z=3,**kwds):
return x+y+z
def goo(x=10,**kwds):
return foo(x=2*x,**kwds)
def moo(y=1,z=1,**kwds):
return goo(x=z+y,z=z+1,q=10,**kwds)
This means I can call any of these with an unsupported keyword as in
moo(y=91,z=11,zeta_variable = 10,**kwds)
and the zeta_variable will be passed through unused because nobody in the calling sequence uses it. Thus, you can inject some other function in the calling sequence that does use this variable, without having to change the call signatures of any of the other functions. Using keyword arguments this way is very common when using Python to wrap other codes. Here’s another example where we can trace how each of the function signatures are satisfied and the rest of the keyword arguments are passed through.
def foo(x=1,y=2,**kwds):
print 'foo: x = %d, y = %d, kwds=%r'%(x,y,kwds)
print '\t',
goo(x=x,**kwds)
def goo(x=10,**kwds):
print 'goo: x = %d, kwds=%r'%(x,kwds)
print '\t\t',
moo(x=x,**kwds)
def moo(z=20,**kwds):
print 'moo: z=%d, kwds=%r'%(z,kwds)
Then, calling the foo function as shown below:
foo(x=1,y=2,z=3,k=20)
Gives the following output:
foo: x = 1, y = 2, kwds={'k': 20, 'z': 3}
goo: x = 1, kwds={'k': 20, 'z': 3}
moo: z=3, kwds={'x': 1, 'k': 20}
Notice how the function signatures of each of the functions are satisfied and the rest of the keyword ar‑ guments are passed through.
8. Functional Programming Idioms
Although not a real functional programming language (i.e., Haskell), Python has useful functional id‑ ioms. These become important in parallel computing frameworks like PySpark, but have become depre‑ cated in Python 3.x.
>>> print map( lambda x: x**2 , range(10))
[0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
>>> [i**2 for i in range(10)]
[0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
>>> reduce(lambda x,y:x+2*y,[0,1,2,3],0)
12
>>> filter(lambda x: x%2, range(10) )
[1, 3, 5, 7, 9]
>>> [i for i in range(10) if i %2 ]
[1, 3, 5, 7, 9]
Pay attention to the recursive problem that reduce solves because reduce is super‑fast in Python. I’ve seen very tricky problems solved using reduce creatively. For example, the least common multiple algo‑ rithm can be effectively implemented using reduce, as shown:
def gcd(a, b):
"""Return greatest common divisor using Euclid's Algorithm."""
while b:
a, b = b, a % b
return a
def lcm(a, b):
"""Return lowest common multiple."""
return a * b // gcd(a, b)
def lcmm(*args):
"""Return lcm of args."""
return reduce(lcm, args)
File Input/Output
It’s straightforward to read and write files using Python. The same pattern applies when writing to other objects, like sockets.
1. Basic file usage
The following is the traditional way to get I/O in Python. The modern way is to use (The with statement).
2. Serialization: Saving Complex objects
Serialization means packing Python objects to be shipped between separate Python processes or sepa‑ rate computers, say, through a network socket, for example. The multiplatform nature of Python means that one cannot be assured that the low‑level attributes of Python objects (say, between platform types or Python versions) will remain consistent.
For the vast majority of situations, the following will work.
>>> import cPickle
>>> mylist = ["This", "is", 4, 13327]
>>> f=open ('myfile.dat','wb') # write‑binary mode
>>> cPickle.dump(mylist, f)
>>> f.close()
>>> f=open ('myfile.dat','rb') # write‑binary mode
>>> print cPickle.load(f)
['This', 'is', 4, 13327]
3. Pickling a Function
The internal state of a function and how it’s hooked into the Python process in which it was created makes it tricky to pickle functions. As with everything in Python, there are ways around this, depending on your use‑case. The following links provide some context:
Dealing with Errors
This is where Python really shines. More modern languages should adopt the Python approach to error handling. The Python approach is to ask for forgiveness rather than permission. This is the basic template.
>>> try:
... # try something
... except:
... # fix something
The above except block with capture and process any kind of exception that is thrown in the try block. Python provides a long list of built‑in exceptions that you can catch and the ability to create your own exceptions, if needed. In addition to catching exceptions, you can raise your own exception using the raise statement. There is also an assert statement that can throw exceptions if certain statements are not True upon assertion (more on this later).
The following are some examples of how to use the exception handling powers of Python.
>>> def some_function():
... try:
... # Division by zero raises an exception
... 10 / 0
... except ZeroDivisionError:
... print "Oops, invalid."
... else:
... # Exception didn't occur, we're good.
... pass
... finally:
... # This is executed after the code block is run
... # and all exceptions have been handled, even
... # if a new exception is raised while handling.
... print "We're done with that."
>>> some_function()
Oops, invalid.
We're done with that.
>>> out = range (3)
>>> try:
... 10 / 0
... except ZeroDivisionError:
... print 'I caught an attempt to divide by zero'
I caught an attempt to divide by zero
>>> try:
... out[999] # raise IndexError
... except ZeroDivisionError:
... print 'I caught an attempt to divide by zero'
Traceback (most recent call last):
...
IndexError: list index out of range
>>> try:
... 1/0 # raise ZeroDivisionError
... out[999]
... except ZeroDivisionError:
... print 'I caught an attempt to divide by zero but I did not try out[999]'
I caught an attempt to divide by zero but I did not try out[999]
>>> try:
... 1/0 # raise ZeroDivisionError
... out[999]
... except IndexError:
... print 'I caught an attempt to index something out of range'
Traceback (most recent call last):
...
ZeroDivisionError: integer division or modulo by zero
>>> try: #nested exceptions
... try: # inner scope
... 1/0
... except IndexError:
... print 'caught index error inside'
... except ZeroDivisionError as e:
... print 'I caught an attempt to divide by zero inside somewhere'
I caught an attempt to divide by zero inside somewhere
>>> try: #nested exceptions with finally clause
... try:
... 1/0
... except IndexError:
... print 'caught index error inside'
... finally:
... print "I am working in inner scope"
... except ZeroDivisionError as e:
... print 'I caught an attempt to divide by zero inside somewhere'
I am working in inner scope
I caught an attempt to divide by zero inside somewhere
>>> try:
... 1/0
... except (IndexError,ZeroDivisionError) as e:
... if isinstance(e,ZeroDivisionError):
... print 'I caught an attempt to divide by zero inside somewhere'
... elif isinstance(e,IndexError):
... print 'I caught an attempt to index something out of range'
I caught an attempt to divide by zero inside somewhere
>>> try: # more detailed arbitrary exception catching
... 1/0
... except Exception as e:
... print type(e)
<type 'exceptions.ZeroDivisionError'>
Power Python Features to Master
1. The under‑appreciated zip function
Python has a built‑in zip function that can combine iterables pair‑wise.
>>> zip(range(3),'abc')
[(0, 'a'), (1, 'b'), (2, 'c')]
>>> zip(range(3),'abc',range(1,4))
[(0, 'a', 1), (1, 'b', 2), (2, 'c', 3)]
The slick part is reversing this operation using the * operation,
>>> x = zip(range(3),'abc')
>>> print x
[(0, 'a'), (1, 'b'), (2, 'c')]
>>> i,j = zip(*x)
>>> print i
(0, 1, 2)
>>> print j
('a', 'b', 'c')
When combined with dict, zip provide a powerful way to build Python dictionaries,
>>> k = range(10)
>>> v = range(10,20)
>>> dict(zip(k,v))
{0: 10, 1: 11, 2: 12, 3: 13, 4: 14, 5: 15, 6: 16, 7: 17, 8: 18, 9: 19}
2. The max function
The max function takes the maximum of a sequence.
>>> max([1,3,4])
4
If the items in the sequence are tuples, then the first item in the tuple is used for the ranking
>>> max([(1,2),(3,4)])
(3,4)
This function takes a key argument that controls how the items in the sequence are evaluated. For ex‑ ample, we can rank based on the second element in the tuple,
>>> max([(1,4),(3,2)],key=lambda i:i[1])
(1,4)
3. The with statement
Set up a context for subsequent code
class ControlledExecution:
def __enter__(self):
#set things up
return thing
def __exit__(self, type, value, traceback):
#tear things down
with ControlledExecution() as thing:
some code
Advanced Language Features
1. Advanced String Formatting
2. Generators
3. Decorators
4. Coroutines
5. Iteration and Iterables
Q.E.D.
To baldly -_- go no man has gone before
|
__label__pos
| 0.846232 |
मेरा प्रश्न चमकदार बीएस में bsCollapsePanel में शीर्षलेख के टॉगलिंग और अनटॉगलिंग की घटना को देखने से संबंधित है।
आइए निम्नलिखित ऐप को एक उदाहरण के रूप में देखें:
library(shiny)
library(shinyBS)
server = function(input, output, session) {
observeEvent(input$p1Button, ({
updateCollapse(session, "collapseExample", open = "Panel 1")
}))
observeEvent(input$styleSelect, ({
updateCollapse(session, "collapseExample", style = list("Panel 1" = input$styleSelect))
}))
output$randomNumber <- reactive(paste0('some random number'))
}
ui = fluidPage(
sidebarLayout(
sidebarPanel(HTML("This button will open Panel 1 using <code>updateCollapse</code>."),
actionButton("p1Button", "Push Me!"),
selectInput("styleSelect", "Select style for Panel 1",
c("default", "primary", "danger", "warning", "info", "success"))
),
mainPanel(
bsCollapse(id = "collapseExample", open = "Panel 2",
bsCollapsePanel("Panel 1", "This is a panel with just text ",
"and has the default style. You can change the style in ",
"the sidebar.", style = "info")
),
verbatimTextOutput('randomNumber')
)
)
)
app = shinyApp(ui = ui, server = server)
मैं चाहता हूं कि ऐप verbatimTextOutput('randomNumber') फ़ील्ड में एक यादृच्छिक संख्या (R चमकदार प्रतिक्रियाशीलता का उपयोग करके) प्रिंट करने में सक्षम हो, जब भी मैं bsCollapsePanel को Panel 1 हेडर पर क्लिक करके खोलता हूं।
मैं सोच रहा था कि shinyjs पैकेज का उपयोग करना संभव हो सकता है लेकिन इन दोनों पैकेजों के एक साथ उपयोग किए जाने के कई उदाहरण नहीं मिले हैं।
1
user974514 19 अप्रैल 2017, 20:46
2 जवाब
सबसे बढ़िया उत्तर
मुझे पूरा यकीन नहीं है कि आप क्या चाहते हैं, लेकिन यह करीब हो सकता है। ये जोड़ हैं:
• आपके Panel 1 शीर्षलेख की निगरानी के लिए एक observeEvent जोड़ा गया।
• "यादृच्छिक संख्या" रखने के लिए एक reactiveValues जोड़ा गया
• जब Panel 1 को पुश किया जाता है, तो उपरोक्त observeEvent हैंडलर में उस मान को बढ़ा दिया जाता है।
यहाँ कोड है:
library(shiny)
library(shinyBS)
server = function(input, output, session) {
rv <- reactiveValues(number=0)
observeEvent(input$p1Button, ({
updateCollapse(session, "collapseExample", open = "Panel 1")
}))
observeEvent(input$styleSelect, ({
updateCollapse(session, "collapseExample", style = list("Panel 1" = input$styleSelect))
}))
observeEvent(input$collapseExample, ({
rv$number <- rv$number+1
}))
output$randomNumber <- reactive(rv$number)
}
ui = fluidPage(
sidebarLayout(
sidebarPanel(HTML("This button will open Panel 1 using <code>updateCollapse</code>."),
actionButton("p1Button", "Push Me!"),
selectInput("styleSelect", "Select style for Panel 1",
c("default", "primary", "danger", "warning", "info", "success"))
),
mainPanel(
bsCollapse(id = "collapseExample", open = "Panel 2",
bsCollapsePanel("Panel 1", "This is a panel with just text ",
"and has the default style. You can change the style in ",
"the sidebar.", style = "info")
),
verbatimTextOutput('randomNumber')
)
)
)
shinyApp(ui = ui, server = server)
और एक स्क्रीन शॉट:
enter image description here
1
Mike Wise 19 अप्रैल 2017, 21:36
ठीक है, माइक वाइज मुझसे तेज था :) अगर किसी कारण से मेरा समाधान भी मददगार है तो मुझे बताएं अन्यथा मैं इसे हटा देता हूं।
library(shiny)
library(shinyjs)
library(shinyBS)
ui = fluidPage(
useShinyjs(),
sidebarLayout(
sidebarPanel(HTML("This button will open Panel1 using <code>updateCollapse</code>."),
actionButton("p1Button", "Push Me!"),
selectInput("styleSelect", "Select style for Panel1",
c("default", "primary", "danger", "warning", "info", "success"))
),
mainPanel(
bsCollapse(id = "collapseExample", open = "Panel 2",
bsCollapsePanel("Panel1", "This is a panel with just text ",
"and has the default style. You can change the style in ",
"the sidebar.", style = "info", id = "me23")
),
verbatimTextOutput('randomNumber')
)
)
)
server = function(input, output, session) {
observeEvent(input$p1Button, ({
updateCollapse(session, "collapseExample", open = "Panel1")
}))
observeEvent(input$styleSelect, ({
updateCollapse(session, "collapseExample", style = list("Panel1" = input$styleSelect))
}))
observe({
runjs("function getAllElementsWithAttribute(attribute){
var matchingElements = [];
var allElements = document.getElementsByTagName('*');
for (var i = 0, n = allElements.length; i < n; i++)
{
if (allElements[i].getAttribute(attribute) !== null)
{
// Element exists with attribute. Add to array.
matchingElements.push(allElements[i]);
}
}
return matchingElements;
};
ahref = getAllElementsWithAttribute('data-toggle');
ahref[0].onclick = function() {
var nmbr = Math.random();
Shiny.onInputChange('randomNumber', nmbr);
};
")
})
output$randomNumber <- reactive(paste0(input$randomNumber))
}
shinyApp(ui = ui, server = server)
जावास्क्रिप्ट कोड आप यहां पा सकते हैं: जब querySelectorAll नहीं है तो विशेषता के आधार पर तत्व प्राप्त करें पुस्तकालयों का उपयोग किए बिना उपलब्ध है?
2
Community 23 मई 2017, 14:47
|
__label__pos
| 0.735332 |
Installation and usage of the iOS & Swift SDKs with Objective-C
Learn how to pick files, enable the image editor and transform images in iOS.
Overview
In this tutorial we’ll be creating a fresh iOS app where we’ll be able to pick files, edit picked images using the built-in image editor and transform images using Filestack’s remote API. We will rely on CocoaPods to handle the external dependency on Filestack framework and all its subdependencies.
IMPORTANT: This tutorial targets Objective-C. If you would rather prefer using Swift, please check our homologous tutorial Installation and usage of the iOS & Swift SDKs instead.
With that said, let’s get started!
Installation
1. Open Xcode and create a new project (File -> New Project), select iOS as the platform and Tabbed App as the template:
2. On the next step, name your project Filestack-Tutorial, leaving all other settings as default:
3. We will be creating our views programmatically so, delete (using Move to Trash) the following files from the project hierarchy:
• FirstViewController.h
• FirstViewController.m
• SecondViewController.h.
• SecondViewController.m.
• Main.storyboard
4. Now click on the project’s root, select the Filestack-Tutorial target, find the Signing section and enable Automatic signing and set up a Team:
5. Change the Main Interface setting from Main to an empty value (we will be creating our UI programmatically). For Device Orientation make sure only Portrait is enabled:
6. Now go to the Info tab, expand URL Types and click the plus (+) button. Set the identifier to com.filestack.tutorial and URL Schemes to tutorial.
7. Add the following keys to Custom iOS Target Properties:
KeyValue
NSPhotoLibraryUsageDescriptionThis demo needs access to the photo library.
NSCameraUsageDescriptionThis demo needs access to the camera.
1. Right-click each of the following 2 images and save them locally on your Mac. We will need them in our project:
2. Now create a new group inside Filestack-Tutorial called Images and add the images you just downloaded to it making sure Copy items if needed is checked. File hierarchy should look like this:
10. Finally, let’s configure an Objective-C bridging header so we can use Swift frameworks from our Objective-C project. Right-click Filestack-Tutorial on the Project Navigator, choose New File… and select Swift File. The name of the file is not important, just make sure you choose Create Bridging Header when asked if you would like to configure an Objective-C bridging header. Once done, you can delete the file with swift extension that was created.
Setup
In case CocoaPods is not already present in your system, you will need to install it using RubyGems:
gem install cocoapods
After that, in your project’s root run:
pod init
A new file called Podfile will be created. Open the file with your favorite text editor and enter the following:
platform :ios, '11.0'
target 'Filestack-Tutorial' do
use_frameworks!
pod 'Filestack', '~> 2.1'
end
Now we are ready to setup our project to use CocoaPods with the pods we need. For that we run the following:
pod install --repo-update
CocoaPods will generate a new Filestack-Tutorial.xcworkspace that we will be using from now on to work on our project. If Filestack-Tutorial.xcodeproj is still open in Xcode, please close it and open Filestack-Tutorial.xcworkspace instead.
In the new workspace we just created, right-click Filestack-Tutorial on the Project Navigator, choose New File… and select Cocoa Touch Class. Name your class FilestackSetup and make it a subclass of NSObject.
Open FilestackSetup.h and add the following contents to it making sure to set your API key and app secret accordingly:
#import <Foundation/Foundation.h>
NS_ASSUME_NONNULL_BEGIN
// Set your app's URL scheme here.
static NSString *appURLScheme = @"tutorial";
// Set your Filestack's API key here.
static NSString *filestackAPIKey = @"YOUR-API-KEY-HERE";
// Set your Filestack's app secret here.
static NSString *filestackAppSecret = @"YOUR-APP-SECRET-HERE";
@class FSFilestackClient;
@interface FilestackSetup : NSObject
@property(nonatomic, strong) FSFilestackClient *client;
+ (FilestackSetup *)sharedSingleton;
@end
NS_ASSUME_NONNULL_END
Now open FilestackSetup.m and add the following contents:
#import "FilestackSetup.h"
@import FilestackSDK;
@import Filestack;
@implementation FilestackSetup
-(instancetype)init {
self = [super init];
if (self) {
FSPolicyCall policyCall =
FSPolicyCallPick | FSPolicyCallRead | FSPolicyCallStat |
FSPolicyCallWrite | FSPolicyCallWriteURL | FSPolicyCallStore |
FSPolicyCallConvert | FSPolicyCallRemove | FSPolicyCallExif;
FSPolicy *policy = [[FSPolicy alloc] initWithExpiry:NSDate.distantFuture
call:policyCall];
FSSecurity *security = [[FSSecurity alloc] initWithPolicy:policy
appSecret:filestackAppSecret
error:nil];
FSConfig *config = [FSConfig new];
config.appURLScheme = appURLScheme;
config.imageURLExportPreset = FSImageURLExportPresetCurrent;
config.maximumSelectionAllowed = 10;
config.availableCloudSources = @[FSCloudSource.dropbox,
FSCloudSource.googleDrive,
FSCloudSource.googlePhotos,
FSCloudSource.customSource];
config.availableLocalSources = @[FSLocalSource.camera,
FSLocalSource.photoLibrary,
FSLocalSource.documents];
self.client = [[FSFilestackClient alloc] initWithApiKey:filestackAPIKey
security:security
config:config
token:nil];
}
return self;
}
+ (FilestackSetup *)sharedSingleton
{
static FilestackSetup *sharedSingleton;
@synchronized(self)
{
if (!sharedSingleton)
sharedSingleton = [FilestackSetup new];
return sharedSingleton;
}
}
@end
Open AppDelegate.m and add the following imports:
#import "FilestackSetup.h"
Replace your existing - application:didFinishLaunchingWithOptions: with:
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
// Override point for customization after application launch.
[FilestackSetup sharedSingleton];
return YES;
}
Setup UI
Our demo app is going to present a tab view controller containing 2 view controllers:
• PickerViewController — we’ll use this view to present the picker
• TransformImagesViewController — we’ll use this view to transform an image using Filestack’s transformation API
OK, so let’s create our 2 view controllers first…
Right-click Filestack-Tutorial on the Project Navigator, choose New File… and select Cocoa Touch Class. Name your class PickerViewController and make it a subclass of UIViewController.
Open PickerViewController.m and add:
#import "PickerViewController.h"
#import "FilestackSetup.h"
@import Filestack;
@import FilestackSDK;
@interface PickerViewController () <FSPickerNavigationControllerDelegate>
@property(nonatomic, strong) UIButton *presentPickerButton;
@end
@implementation PickerViewController
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view.
self.presentPickerButton = [UIButton buttonWithType:UIButtonTypeSystem];
[self.presentPickerButton setTitle:@"Present Picker"
forState:UIControlStateNormal];
[self.presentPickerButton addTarget:self
action:@selector(presentPicker:)
forControlEvents:UIControlEventTouchUpInside];
self.presentPickerButton.translatesAutoresizingMaskIntoConstraints = NO;
[self.view addSubview:self.presentPickerButton];
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:self.presentPickerButton
attribute:NSLayoutAttributeCenterX
relatedBy:NSLayoutRelationEqual
toItem:self.view
attribute:NSLayoutAttributeCenterX
multiplier:1
constant:0]];
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:self.presentPickerButton
attribute:NSLayoutAttributeCenterY
relatedBy:NSLayoutRelationEqual
toItem:self.view
attribute:NSLayoutAttributeCenterY
multiplier:1
constant:0]];
}
- (IBAction)presentPicker:(id)sender {}
@end
Right-click Filestack-Tutorial on the Project Navigator, choose New File… and select Cocoa Touch Class. Name your class TransformImagesViewController and make it a subclass of UIViewController.
Open TransformImagesViewController.m and add:
#import "TransformImagesViewController.h"
#import "FilestackSetup.h"
@import FilestackSDK;
@import Filestack;
@interface TransformImagesViewController ()
@property(nonatomic, strong) NSURL *originalImageURL;
@property(nonatomic, strong) NSURL *placeholderImageURL;
@property(nonatomic, strong) UILabel *originalImageLabel;
@property(nonatomic, strong) UIImageView *originalImageView;
@property(nonatomic, strong) UIImageView *transformedImageView;
@property(nonatomic, strong) UIButton *transformImageButton;
@property(nonatomic, strong) UIStackView *stackView;
@end
@implementation TransformImagesViewController
- (NSURL *)originalImageURL {
if (!_originalImageURL) {
_originalImageURL = [NSBundle.mainBundle URLForResource:@"original" withExtension:@"jpg"];
}
return _originalImageURL;
}
- (NSURL *)placeholderImageURL {
if (!_placeholderImageURL) {
_placeholderImageURL = [NSBundle.mainBundle URLForResource:@"placeholder" withExtension:@"png"];
}
return _placeholderImageURL;
}
-(UILabel *)originalImageLabel {
if (!_originalImageLabel) {
// Setup original image label
UILabel *label = [UILabel new];
label.text = @"Original Image";
label.font = [UIFont preferredFontForTextStyle:UIFontTextStyleSubheadline];
label.textColor = UIColor.lightGrayColor;
[label setContentCompressionResistancePriority:UILayoutPriorityRequired
forAxis:UILayoutConstraintAxisVertical];
_originalImageLabel = label;
}
return _originalImageLabel;
}
-(UIImageView *)originalImageView {
if (!_originalImageView) {
// Setup original image view
UIImage *originalImage = [UIImage imageWithContentsOfFile:self.originalImageURL.path];
UIImageView *imageView = [[UIImageView alloc] initWithImage:originalImage];
imageView.contentMode = UIViewContentModeScaleAspectFit;
NSLayoutConstraint *constraint = [NSLayoutConstraint constraintWithItem:imageView
attribute:NSLayoutAttributeHeight
relatedBy:NSLayoutRelationEqual
toItem:nil
attribute:NSLayoutAttributeHeight
multiplier:1
constant:220];
[constraint setActive:YES];
_originalImageView = imageView;
}
return _originalImageView;
}
-(UIImageView *)transformedImageView {
if (!_transformedImageView) {
// Setup transformed image view
UIImage *placeholderImage = [UIImage imageWithContentsOfFile:self.placeholderImageURL.path];
UIImageView *imageView = [[UIImageView alloc] initWithImage:placeholderImage];
imageView.contentMode = UIViewContentModeScaleAspectFit;
NSLayoutConstraint *constraint = [NSLayoutConstraint constraintWithItem:imageView
attribute:NSLayoutAttributeHeight
relatedBy:NSLayoutRelationEqual
toItem:nil
attribute:NSLayoutAttributeHeight
multiplier:1
constant:220];
[constraint setActive:YES];
_transformedImageView = imageView;
}
return _transformedImageView;
}
-(UIButton *)transformImageButton {
if (!_transformImageButton) {
// Setup transformed image button
UIButton *button = [UIButton buttonWithType:UIButtonTypeSystem];
[button setTitle:@"Transform Image"
forState:UIControlStateNormal];
[button addTarget:self
action:@selector(transformImage:)
forControlEvents:UIControlEventTouchUpInside];
_transformImageButton = button;
}
return _transformImageButton;
}
- (UIStackView *)stackView {
if (!_stackView) {
// Setup stack view
UIStackView *stackView = [[UIStackView alloc] initWithArrangedSubviews:@[self.originalImageLabel,
self.originalImageView,
self.transformImageButton,
self.transformedImageView
]];
stackView.axis = UILayoutConstraintAxisVertical;
stackView.alignment = UIStackViewAlignmentCenter;
stackView.distribution = UIStackViewDistributionFillProportionally;
stackView.spacing = 22;
stackView.translatesAutoresizingMaskIntoConstraints = NO;
_stackView = stackView;
}
return _stackView;
}
- (void)viewDidLoad {
// Add stack view to view hierarchy
[self.view addSubview:self.stackView];
}
- (void)viewDidAppear:(BOOL)animated {
// Setup stack view constraints
NSDictionary<NSString *, id> *views = @{@"stackView": self.stackView};
NSArray *h = [NSLayoutConstraint constraintsWithVisualFormat:@"H:|-22-[stackView]-22-|"
options:0
metrics:nil
views:views];
NSArray *w = [NSLayoutConstraint constraintsWithVisualFormat:@"V:|-top-[stackView]-bottom-|"
options:0
metrics:@{@"top": @(self.view.safeAreaInsets.top + 22),
@"bottom": @(self.view.safeAreaInsets.bottom + 22)}
views:views];
// Remove existing view constraints
[self.view removeConstraints:self.view.constraints];
// Add new view constraints
[self.view addConstraints:h];
[self.view addConstraints:w];
[super viewDidAppear:animated];
}
-(IBAction)transformImage:(id)sender {}
@end
Once we have the 2 view controllers set up, let’s define our tab bar view controller.
Right-click Filestack-Tutorial on the Project Navigator, choose New File… and select Cocoa Touch Class. Name your class TabBarViewController and make it a subclass of UITabBarController.
Open TabBarViewController.m and add:
#import "TabBarController.h"
#import "PickerViewController.h"
#import "TransformImagesViewController.h"
@implementation TabBarController
-(void)viewDidLoad {
self.view.backgroundColor = UIColor.whiteColor;
PickerViewController *pickerViewController = [PickerViewController new];
pickerViewController.tabBarItem = [[UITabBarItem alloc] initWithTitle:@"Image Picker"
image:[UIImage imageNamed:@"first"]
tag:0];
TransformImagesViewController *transformImagesViewController = [TransformImagesViewController new];
transformImagesViewController.tabBarItem = [[UITabBarItem alloc] initWithTitle:@"Transform Image"
image:[UIImage imageNamed:@"second"]
tag:0];
self.viewControllers = @[pickerViewController, transformImagesViewController];
}
@end
Finally, open AppDelegate.m and replace - application:didFinishLaunchingWithOptions: with:
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
// Override point for customization after application launch.
[FilestackSetup sharedSingleton];
// Added code — we set our TabBarController as the window's root view controller
// and make window key and visible.
self.window = [[UIWindow alloc] initWithFrame:UIScreen.mainScreen.bounds];
self.window.rootViewController = [[UINavigationController alloc] initWithRootViewController:[TabBarController new]];
[self.window makeKeyAndVisible];
return YES;
}
We are also going to add a helper function to simplify alert presentation. Right-click Filestack-Tutorial on the Project Navigator, choose New Group and name it Categories. Now, right-click Categories and choose New File… and select Objective-C. Name it PresentAlert and set class to UIViewController.
Open UIViewController+PresentAlert.h and add:
#import <UIKit/UIKit.h>
NS_ASSUME_NONNULL_BEGIN
@interface UIViewController (PresentAlert)
-(void)presentAlert:(NSString*)title message:(NSString *)message;
@end
NS_ASSUME_NONNULL_END
Now open UIViewController+PresentAlert.m and add:
#import "UIViewController+PresentAlert.h"
@implementation UIViewController (PresentAlert)
-(void)presentAlert:(NSString*)title message:(NSString *)message {
UIAlertController *alertController = [UIAlertController alertControllerWithTitle:title
message:message
preferredStyle:UIAlertControllerStyleAlert];
[alertController addAction:[UIAlertAction actionWithTitle:@"OK"
style:UIAlertActionStyleDefault
handler:nil]];
[self presentViewController:alertController
animated:NO
completion:nil];
}
@end
Our UI and helper code are now ready and all left to do is to add the handling for - presentPicker: and - transformImage:. That’s exactly what we will be doing in the next steps.
Picker integration
Open PickerViewController.m and add the following implementation to - presentPicker::
- (IBAction)presentPicker:(id)sender {
FSFilestackClient *fsClient = [FilestackSetup sharedSingleton].client;
if (!fsClient)
return;
// Store options for your uploaded files.
// Here we are saying our storage location is S3 and access for uploaded files should be public.
FSStorageOptions *storeOptions = [[FSStorageOptions alloc] initWithLocation:FSStorageLocationS3
access:FSStorageAccessPublic];
// Instantiate picker by passing the `StorageOptions` object we just set up.
FSPickerNavigationController *picker = [fsClient pickerWithStoreOptions:storeOptions];
// Set our view controller as the picker's delegate.
picker.pickerDelegate = self;
// Finally, present the picker on the screen.
[self presentViewController:picker
animated:YES
completion:nil];
}
In order to receive notifications from the picker (e.g. when files are uploaded to the storage location), we’ll want our view controller to implement the PickerNavigationControllerDelegate protocol. We already set up our view controller as the picker’s delegate in our code, so all that is left to do is to implement the protocol.
First, make sure to add conformance to FSPickerNavigationControllerDelegate to PickerViewController:
@interface PickerViewController () <FSPickerNavigationControllerDelegate>
Then add the implementation:
#pragma mark - FSPickerNavigationControllerDelegate Implementation
// A file was picked from a cloud source
- (void)pickerStoredFileWithPicker:(FSPickerNavigationController * _Nonnull)picker response:(FSStoreResponse * _Nonnull)response {
[picker dismissViewControllerAnimated:NO completion:^{
NSString *handle = response.contents[@"handle"];
NSError *error = response.error;
if (handle != nil) {
[self presentAlert:@"Success"
message:[NSString stringWithFormat:@"Finished storing file with handle: %@", handle]];
} else if (error != nil) {
[self presentAlert:@"Error"
message:[NSString stringWithFormat:@"Error Uploading File: %@", error.localizedDescription]];
}
}];
}
// A file or set of files were picked from the camera, photo library, or Apple's Document Picker
- (void)pickerUploadedFilesWithPicker:(FSPickerNavigationController * _Nonnull)picker responses:(NSArray<FSNetworkJSONResponse *> * _Nonnull)responses {
[picker dismissViewControllerAnimated:NO completion:^{
NSMutableArray<NSString *> *handles = [NSMutableArray arrayWithCapacity:10];
NSMutableArray<NSString *> *errorMessages = [NSMutableArray arrayWithCapacity:10];
for (FSNetworkJSONResponse *response in responses) {
NSString *handle = response.json[@"handle"];
NSError *error = response.error;
if (handle != nil) {
[handles addObject:handle];
}
if (error != nil) {
[errorMessages addObject:error.localizedDescription];
}
}
if (errorMessages.count == 0) {
NSString *joinedHandles = [handles componentsJoinedByString:@", "];
[self presentAlert:@"Success"
message:[NSString stringWithFormat:@"Finished storing files with handles: %@", joinedHandles]];
} else {
NSString *joinedErrors = [errorMessages componentsJoinedByString:@", "];
[self presentAlert:@"Error Uploading File"
message:joinedErrors];
}
}];
}
Image editor integration
Wouldn’t it be nice to allow users to edit images before they are uploaded? Luckily this is a simple config setting.
Open your FilestackSetup.m and locate:
config.availableLocalSources = @[FSLocalSource.camera,
FSLocalSource.photoLibrary,
FSLocalSource.documents];
Add the following line right below it:
config.showEditorBeforeUpload = YES;
Now, after the user is finished picking files it will have the chance to edit any of the files that happen to be images before they are uploaded to the storage location.
Displaying and transforming files
Open the TransformImagesViewController.m file and let’s first add a helper function:
#pragma mark - Private Methods
-(NSURL *)documentURLFor:(FSFileLink *)filelink {
NSURL *url = [NSFileManager.defaultManager URLsForDirectory:NSDocumentDirectory
inDomains:NSUserDomainMask].firstObject;
return [[url URLByAppendingPathComponent:filelink.handle] URLByAppendingPathExtension:@"jpg"];
}
And now add the actual implementation for - transformImage::
-(IBAction)transformImage:(id)sender {
FSFilestackClient *fsClient = [FilestackSetup sharedSingleton].client;
if (!fsClient)
return;
[self.transformImageButton setEnabled:NO];
[self.transformImageButton setTitle:@"Uploading image..." forState:UIControlStateDisabled];
FSStorageOptions *storeOptions = [[FSStorageOptions alloc] initWithLocation:FSStorageLocationS3
access:FSStorageAccessPublic];
[fsClient uploadFrom:self.originalImageURL
storeOptions:storeOptions
useIntelligentIngestionIfAvailable:YES
queue:dispatch_get_main_queue()
uploadProgress:nil
completionHandler:^(FSNetworkJSONResponse * _Nullable response) {
NSError *error = response.error;
NSString *handle = response.json[@"handle"];
if (error != nil) {
[self presentAlert:@"Transformation Error"
message:error.localizedDescription];
} else if (handle != nil) {
[self.transformImageButton setTitle:@"Transforming image..."
forState:UIControlStateDisabled];
// Obtain Filelink for uploaded file.
FSFileLink *uploadedFilelink = [fsClient.sdkClient fileLinkFor:handle];
// Obtain transformable for Filelink.
FSTransformable *transformable = [uploadedFilelink transformable];
// Add some transformations.
[transformable add:[[[[[FSResizeTransform new]
width:220]
height:220]
fit:FSTransformFitCrop]
align:FSTransformAlignCenter]];
[transformable add:[[[FSRoundedCornersTransform new]
radius:20]
blur:0.25]];
// Store transformed image in Filestack storage.
[transformable storeUsing:storeOptions
base64Decode:NO
queue:dispatch_get_main_queue()
completionHandler:^(FSFileLink * _Nullable filelink, FSNetworkJSONResponse * _Nonnull response) {
// Remove uploaded image from Filestack storage.
[uploadedFilelink deleteWithParameters:nil
queue:dispatch_get_main_queue()
completionHandler:^(FSNetworkDataResponse * _Nonnull response) {
// NO-OP;
}];
if (filelink != nil) {
NSURL *documentURL = [self documentURLFor:filelink];
[self.transformImageButton setTitle:@"Downloading transformed image..."
forState:UIControlStateDisabled];
// Download transformed image from Filestack storage.
[filelink downloadWithDestinationURL:documentURL
parameters:nil
queue:dispatch_get_main_queue()
downloadProgress:nil
completionHandler:^(FSNetworkDownloadResponse * _Nonnull response) {
// Remove transformed image from Filestack storage.
[filelink deleteWithParameters:nil
queue:dispatch_get_main_queue()
completionHandler:^(FSNetworkDataResponse * _Nonnull response) {
// NO-OP;
}];
[self.transformImageButton setEnabled:YES];
// Update image view's image with our transformed image.
if (response.destinationURL != nil) {
self.transformedImageView.image = [UIImage imageWithContentsOfFile:response.destinationURL.path];
}
}];
} else if (response.error != nil ) {
[self.transformImageButton setEnabled:YES];
[self presentAlert:@"Transformation Error"
message:error.localizedDescription];
}
}];
}
}];
}
Resources
|
__label__pos
| 0.941077 |
Solved – Why do we calculate pooled standard deviations by using variances
Why do we calculate the pooled standard deviation by averaging the variances and taking the square root, rather than averaging the standard deviations directly?
Edit: this came up in the context of creating an effect size for a paired samples t-test, but if the answer varies across contexts I am interested to learn about that as well.
We work with variances rather than standard deviations because variances have special properties.
In particular, variances of sums and differences of variables have a simple form, and if the variables are independent, the result is even simpler.
That is, if two variables are independent, the variance of the difference is the sum of the variances ("variances add" — but standard deviations don't).
Specifically, in say a two-sample t test, we're trying to find the standard deviation of the difference in sample means. We can use basic properties of variance (linked above) to see that the variance of the individual sample means is $sigma^2/n$, which we can estimate by $s^2/n$ for each sample.
Now that we have the variance of each the means, we can use the "variances add" result to get that the variance of the difference of the means is the sum of the two variances of the sample means. So the standard deviation of the distribution of the difference in means (the standard error of the difference in means) is the square root of that sum.
This works quite directly for the Welch t-test, where we estimate $text{Var}(bar{X}-bar{Y})$ by $s_x^2/n_x+s_y^2/n_y$. The equal-variance version works using the same idea but because the variances are assumed identical, there we produce a single overall estimate of $sigma^2$ from both samples. That is, we add together all the squared deviations from the corresponding group mean before dividing by the total d.f. from the two groups (each loses 1 d.f. because we measure deviations from the individual group means). This corresponds to a form of d.f.-weighted average of the individual variances $s^2_p=w_xs^2_x+w_ys^2_y$ where $w_x=text{df}_x/(text{df}_x+text{df}_y)$. Then that single estimate of pooled variance $s^2_p$ is used in an estimate of the variance of the difference in means. Since $text{Var}(bar{X})=sigma^2/n_x$ and $text{Var}(bar{Y})=sigma^2/n_y$, again the variance of the sum is the sum of the variances, so $text{Var}(bar{X}-bar{Y})=sigma^2/n_x+sigma^2/n_y$, which we again then estimate by replacing $sigma^2$ by the estimate $s^2_p$.
In either case, we can standardize our difference in means by dividing by the corresponding estimate of standard error. In both cases this is where the denominator of the $t$-statistic comes from.
Similar results come up in other cases.
Similar Posts:
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__label__pos
| 0.999993 |
Data Structures
From TaDa Wiki
Jump to: navigation, search
I [...] claim that the difference between a bad programmer and a good one is whether he considers his code or his data structures more important. - Linus Torvalds
Smart data structures and dumb code works a lot better than the other way around. - Eric S. Raymond, The Cathedral and The Bazaar
Data Structures -- They're Not All the Same
One things most casual programmers don't realize is that different data structures -- lists, vectors, matrices, dataframes, etc. -- aren't just different from the perspective of the user; they actually result in the computer handling data in very different ways. As a result, each structure has its own strengths and weaknesses, and for some operations the speed difference between code that uses the right structure and the wrong structure can easily be many orders of magnitudes, especially in data science.
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| 0.937901 |
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Error correction scheme for facsimile over a packet switched network
Title: Error correction scheme for facsimile over a packet switched network.
Abstract: A method for correcting at least one error in a facsimile transmission over a packet switched communications network includes the steps of: detecting, by a first gateway coupled to the communications network, at least one missing data packet in a sequence of data packets transmitted from a second gateway coupled to the communications network during the facsimile transmission; transmitting, from the first gateway, a request for retransmission of the missing data packet to the second gateway; determining whether the missing data packet is available for retransmission; and, when the missing data packet is available, retransmitting the missing data packet to the first gateway. ...
USPTO Applicaton #: #20120110403 - Class: 714748 (USPTO) - 05/03/12 - Class 714
Inventors: Ximing Chen, Herbert B. Cohen, Chengzhou Li
view organizer monitor keywords
The Patent Description & Claims data below is from USPTO Patent Application 20120110403, Error correction scheme for facsimile over a packet switched network.
FIELD OF THE INVENTION
The present invention relates generally to the electrical, electronic, and computer arts, and more particularly relates to facsimile communications.
BACKGROUND OF THE INVENTION
A traditional analog facsimile (or fax) generally involves the transmission of scanned-in printed material (e.g., text, photographs, or the like), usually to a telephone number associated with a printer or other output device via a public switched telephone network (PSTN), as specified, for example, in the International Telecommunication Union (ITU) T.30 standard (see, e.g., ITU-T Recommendation T30, Procedures for Document Facsimile Transmission in the General Switched Telephone Network, SERIES T: TERMINALS FOR TELEMATIC SERVICES, September 2005, the disclosure of which is incorporated by reference herein in its entirety for all purposes). The original source document is scanned in by the fax machine, which treats the contents as a single fixed graphic image, converting it to a bitmap. Once in this digital form, the information is transmitted as electrical signals through the telephone system. The receiving fax machine reconverts the coded image and prints a paper copy of the document.
Despite efforts to become a paperless society and regardless of the prevalence of email communications, fax transmission of printed materials (e.g., text or images) remains vital, particularly for business users. One reason for the continued popularity of faxes is that, unlike email attachments or digital signatures, the signature on a fax document is legally binding. Moreover, fax documents retain the format of the original source document and are virtually uneditable.
As the transmission of voice over the internet, using voice over internet protocol (VoIP) technology, permeates private and public organizations, such organizations have found it desirable to leverage the value and convenience of their single, distributed Internet Protocol (IP) communications network. Since fax transmissions generally utilize the same facilities as voice communications, it is becoming increasingly popular to implement traditional analog fax transmissions using facsimile over internet protocol (FoIP) as specified, for example, in the International Telecommunication Union (ITU) T.38 standard (see, e.g., ITU-T Recommendation T.38, Group 3 Protocols, Procedures for Real-time Group 3 Facsimile Communication Over IP Networks, SERIES T: TERMINALS FOR TELEMATIC SERVICES, FACSIMILE, April 2007, the disclosure of which is incorporated by reference herein in its entirety for all purposes).
The T.38 fax protocol supports the transmission of fax data across an IP network in real time, much like the original Group 3 (G3) fax standards did for the traditional PSTN. In this manner, T.38 preserves the traditional fax environment and yet allows faxes to be successfully sent and received by dynamically adjusting the transmitted fax signal to compensate for jitter, latency, and packet loss, which are common in the IP network. Without T.38, fax devices, which are sensitive to timing, would otherwise experience difficulty reliably sending and receiving faxes over an IP network. However, while the T.38 fax protocol addresses some of the problems associated with sending and receiving faxes in real-time over a packet network, several problems remain.
SUMMARY
OF THE INVENTION
The present invention, in illustrative embodiments thereof, provides an innovative error correction scheme for efficiently facilitating facsimile transmissions over a packet switched communications network. Techniques of the invention advantageously address problems associated with conventional error correction methodologies used for facsimile transmissions over packet switched communications networks.
In accordance with one embodiment of the invention, a method for correcting at least one error in a facsimile transmission over a packet switched communications network includes the steps of: detecting, by a first gateway coupled to the communications network, at least one missing data packet in a sequence of data packets transmitted from a second gateway coupled to the communications network during the facsimile transmission; transmitting, from the first gateway, a request for retransmission of the missing data packet(s) to the second gateway; determining whether the missing data packet(s) is(are) available for retransmission; and, when the missing data packet(s) is(are) available, retransmitting the missing data packet(s) to the first gateway.
In accordance with another embodiment of the invention, an apparatus for correcting at least one error in a facsimile transmission over a packet switched communications network includes at least a first gateway adapted for connection to the packet switched communications network. The first gateway includes at least one processor operative: (i) to detect at least one missing data packet in a sequence of data packets transmitted from a second gateway coupled to the communications network during the facsimile transmission; (ii) to transmit a request for retransmission of the missing data packet(s) to the second gateway; and (iii) to receive the missing data packet(s) retransmitted from the second gateway when the missing data packet(s) is(are) available for retransmission.
In accordance with yet another embodiment of the invention, an apparatus for correcting at least one error in a facsimile transmission over a packet switched communications network includes at least a first gateway adapted for connection to the packet switched communications network. The first gateway includes memory and at least one processor coupled to the memory. The processor is operative: (i) to transmit at least one facsimile data packet in a sequence of data packets to a second gateway coupled to the communications network during the facsimile transmission; (ii) to store, in the memory, a copy of the data packet; (iii) to receive a request for retransmission of at least one missing data packet, the request for retransmission being sent by the second gateway and identifying the missing data packet(s) in the sequence of data packets detected by the second gateway; and (iv) to retransmit the missing data packet(s) to the second gateway when the missing data packet(s) is(are) available in the memory for retransmission.
These and other features, objects and advantages of the present invention will become apparent from the following detailed description of illustrative embodiments thereof, which is to be read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The following drawings are presented by way of example only and without limitation, wherein like reference numerals indicate corresponding elements throughout the several views, and wherein:
FIG. 1 is a block diagram depicting at least a portion of an illustrative dedicated IP-aware fax engine adapted for providing fax communications over an IP network;
FIG. 2 is a block diagram depicting a simple exemplary FoIP network in which principles of the present invention may be implemented;
FIG. 3 is a block diagram depicting at least a portion of an exemplary fax transmission stream in which fax packets are sent in varying time intervals;
FIG. 4 is a block diagram depicting at least a portion of exemplary fax transmission stream in which idle packets are inserted into the packet sequence such that each packet interval is not greater than a prescribed value, according to an embodiment of the present invention;
FIG. 5 depicts at least a portion of an illustrative data transfer between a transmit gateway and a receive gateway during a FoIP session, according to an embodiment of the present invention; and
FIG. 6 is a block diagram depicting an exemplary data processing system, according to an aspect of the present invention.
It is to be appreciated that elements in the figures are illustrated for simplicity and clarity. Common but well-understood elements that may be useful or necessary in a commercially feasible embodiment may not be shown in order to facilitate a less hindered view of the illustrated embodiments.
DETAILED DESCRIPTION
OF PREFERRED EMBODIMENTS
Principles of the present invention will be described herein in the context of illustrative embodiments of a packet recovery methodology and apparatus for ITU T.38-based FoIP. It is to be appreciated, however, that the invention is not limited to the specific apparatus and methods illustratively shown and described herein. Rather, aspects of the invention are directed broadly to techniques for efficiently correcting errors which may occur in a facsimile transmission over a packet switched communications network. In various embodiments, the innovative error correction scheme for facsimile over a packet switched network is implemented, for example, in a client computing device, a residential gateway, a network device and the like, to support facsimile over packet switched network services to remote facsimile machines. Techniques of the invention may be employed either alone or in conjunction with one or more existing error correction methodologies to thereby enhance such existing methods.
While illustrative embodiments of the invention will be described herein with reference to an ITU T.38 protocol, it is to be appreciated that the invention is not limited to use with this or any particular protocol(s). Rather, principles of the invention may be extended to essentially any facsimile communications protocol, both standard and non-standard. Moreover, it will become apparent to those skilled in the art given the teachings herein that numerous modifications can be made to the embodiments shown that are within the scope of the present invention. That is, no limitations with respect to the specific embodiments described herein are intended or should be inferred.
FIG. 1 is a block diagram depicting at least a portion of an illustrative dedicated IP-aware fax engine 100 adapted for providing fax communications over an IP network. The IP-aware fax engine 100, which may be implemented in an IP fax machine or other fax device, comprises a T.30 fax protocol stack 102 and a T.38 protocol stack 104 coupled to the T.30 fax protocol stack. Although depicted as separate functional units, it is to be appreciated that the T.30 fax protocol stack 102 and T.38 protocol stack may be integrated together within the same block, either alone or with other functional blocks (e.g., circuitry, software modules, etc.).
While not explicitly shown, the IP-aware fax engine 100 may further include a modem controller and fax data pump. Fax image data, representative of printed materials (e.g., text, photographs, or the like) to be transmitted, may be sent through the IP-aware fax engine 100, where they are properly formatted by the modem controller and modulated by the fax data pump for transmission via the IP network. In the IP network, an IP-based fax session may or may not require a modem controller and data pump, depending on the application employed.
The IP-aware fax engine 100 further comprises an IP fax packet buffer 106, or alternative buffer. Buffer 106 is operative to provide an interface between the IP-aware fax engine 100 and an IP network (IPN) 108. Buffer 106 is preferably operative to receive data packets from the T.38 protocol stack 104 and reformat them for transmission over the IP network 108. Likewise, packets received from the IP network 108 by the buffer 106 are preferably reformatted by the buffer for use by the T.38 protocol stack 104.
IP-aware fax engine 100 may be controlled by one or more user applications 110 via an IP signaling protocol unit 112, or an alternative interface/control block. IP signaling protocol unit 112 preferably interfaces with the IP-aware fax engine 100, and sets up fax calls using a known communications protocol, such as, for example, Session Initiation Protocol (SIP), ITU-T H.323 (see, e.g., ITU-T Recommendation H.323, Systems and terminal equipment for audiovisual services, Packet-based multimedia communications systems, SERIES H: AUDIOVISUAL AND MULTIMEDIA SYSTEMS, INFRASTRUCTURE OF AUDIOVISUAL SERVICES, December 2009, the disclosure of which is incorporated by reference herein in its entirety for all purposes), or an alternative control and/or signaling protocol. As previously stated, it is to be understood that the invention is not limited to use with any specific communications protocol(s).
The T.30 fax protocol stack 102 is operative to receive fax image data and/or control signals from, or transmit fax image data and/or controls signal to, user application 110. T.30 fax protocol stack 102 is preferably further operative to specify the procedures that a sending and receiving terminal use to set up a fax call, determine the image size, encoding, and transfer speed, the demarcation between pages, and/or the termination of the call, among other functions, according to the T.30 standard. The T.38 protocol stack 104 is operative to “fool” the terminal into thinking that it's communicating directly with another T.30 terminal. T.38 protocol stack 104, in conjunction with buffer 106, will also preferably correct for network delays with so-called spoofing techniques, and missing or delayed packets with fax-aware buffer-management techniques (e.g., store-and-forward processing).
There are two error correction schemes specified in the ITU-T T.38 standard; namely, (i) packet redundancy and (ii) forward error correction (FEC). These two schemes are intended to handle potential packet losses in the IP network which can often occur as a result of the nature of the IP network. While FEC is optional in the T.38 standard, the redundancy scheme is mandatory in the sense that all T.38 gateways must be able to decode the T.38 IP fax packet that uses the redundancy scheme. The term “gateway” as used herein is intended to broadly refer to a device, node or other functional unit operative in a communications network to interface with another network (or networks) which uses a different communications protocol(s). A gateway generally performs protocol translation/mapping for interconnecting networks with different network protocol topologies.
In practice, there are key disadvantages associated with existing error correction schemes. First, both error correction schemes (packet redundancy and FEC) substantially increase the bandwidth of a T.38/FoIP channel, which is undesirable. By way of example only, Group 3 fax transmissions, which conform to the ITU-T Recommendations T.30 and T.4 (see, e.g., ITU-T Recommendation T4, Standardization of Group 3 facsimile terminals for document transmission, SERIES T: TERMINALS FOR TELEMATIC SERVICES, July 2003, the disclosure of which is incorporated by reference herein in its entirety for all purposes), are digital formats that take advantage of digital compression schemes to greatly reduce transmission times. For G3 with V.34 modulation, also referred to as “Super G3” fax, with redundancy=3, the data bandwidth of T.38 traffic can be more than 134.4 kilobits per second (kbps) (i.e., 33.6 kbps×4), which is much higher than an ITU-T G.711 voice-band-data (VBD) channel (see, e.g., ITU-T Recommendation G.711, Pulse Code Modulation (PCM) of Voice Frequencies, General Aspects of Digital Transmission Systems, Terminal Equipments, November 1988, the disclosure of which is incorporated by reference herein in its entirety for all purposes), which transmits data at 64 kbps.
One touted advantage of T.38/FoIP is regarded to be its low bandwidth in comparison to other methodologies, such as, for example, a G.711 VBD channel. With standard error correction methods, however, the bandwidth advantage offered by T.38 is essentially negated.
Another disadvantage with the existing error correction schemes is that such existing schemes, even without consideration for the high cost of bandwidth, are generally ineffective at handling burst packet losses which are common in IP networks. With a redundancy scheme, if the packet redundancy is set to n (where n is typically a small number, e.g., less than 3 for data packets in most cases), only a maximum of n packets can be recovered during a burst packet loss. For example, consider the illustrative case where n=3 and 10 packets in a sequence are lost. In this scenario, only the last three lost packets can be recovered and the remaining seven packets will be lost. While n can be set higher to increase the number of packets that can be recovered during a burst packet loss (the T.38 specification does not impose a limit on n), there is a significant system resource and performance penalties for doing so. Hence, this approach is not sufficient for fax transmissions over an IP network which is susceptible to burst packet losses.
Accordingly, techniques of the present invention, in illustrative embodiments thereof, offer an alternative error correction methodology for fax transmissions over an IP network which is superior to conventional error correction approaches. Specifically, in the context of an exemplary T.38 FoIP session, aspects of the invention provide a retransmit-on-demand (ROD) methodology for recovering lost packets. As will be described in further detail below, an apparatus (e.g., fax receiver, etc.) operative to receive T.38 packets, or packets using an alternative communications protocol, requests retransmission of the lost (or potentially lost) packets based at least in part on received information. Because of the half-duplex nature of fax transmissions, an apparatus (e.g., fax transmitter, etc.) operative to transmit T.38 packets is adapted to send one or more newly devised frames (e.g., “keep-alive” or “idle” frames) periodically when data is not available from a data pump included in the fax apparatus or from the PSTN line.
FIG. 2 is a block diagram depicting a simple exemplary FoIP network 200 in which principles of the present invention may be implemented. As apparent from the figure, network 200 preferably includes a transmit (Tx) fax machine 202 operatively coupled to a T.38 transmit gateway 206 through a first PSTN 204. The T.38 transmit gateway 206 is, in turn, operatively coupled to a T.38 receive (Rx) gateway 210 through an IP network 208. The T.38 receive gateway 210 is then operatively coupled to a receive fax machine 214 through a second PSTN 212. Transmit fax machine 202 may be implemented as a first fax terminal or other fax apparatus, configured in a transmit mode of operation. Similarly, Receive fax machine 214 may be implemented as a second fax terminal configured in a receive mode of operation. In other words, a fax terminal is typically capable of operation in either a transmit or a receive mode of operation at any given time.
T.38 essentially defines a protocol which supports the use of the T.30 protocol in both the transmit fax machine 202 (i.e., sender terminal) and the receive fax machine 214 (i.e., recipient terminal). T.38 transmit gateway 206 provides an interface between the PSTN 204 and IP network 208 preferably by modifying the T.30 protocol commands and information received from the transmit fax machine 202 on the PSTN side to keep network delays on the IP network side from causing the transaction to fail. This may be accomplished, for example, by padding image lines or deliberately causing a message to be re-transmitted to render network delays substantially transparent to the receiving fax machine 214. Similarly, the T.38 receive gateway 210 is operative to modify fax packets received from the IP network 208 and to deliver the fax packets to the receive fax machine 214 in a manner which ensures a relatively smooth flow of PSTN data upon their release. Thus, as previously stated, the T.38 protocol is operative to “fool” the fax terminal into thinking that it's communicating directly with another T.30 terminal.
As stated above, packet loss is very common in most IP networks. Missing packets will often cause a fax session to fail at worst or to generate one or more image lines in error at best. To insure the reliability of a T.38-based FoIP session, two standard packet recovery schemes have been introduced; namely, redundancy and forward error correction (FEC). These schemes not only increase data bandwidth, but are also not able to sufficiently handle burst packet losses. Techniques of the present invention, in accordance with embodiments thereof, advantageously provide an enhanced error correction methodology which addresses both of these problems.
According to an aspect of the invention, a retransmit-on-demand (ROD) methodology is provided in which a FoIP (e.g., T.38-capable) gateway/analog telephone adapter (ATA), for interfacing between an analog PSTN and an IP network (or alternative packet-based network), sends a retransmission request of one or more specified packets based at least in part on information that has been received and/or an elapsed time from a last received packet. The peer gateway/ATA preferably retransmits the packets, assuming the packets are still available, immediately upon receiving the request or within a prescribed time thereafter.
A fax transmission is, in most of cases, a half-duplex process. In a FoIP session, data transfer from one gateway to another is generally not continuous; that is, the time interval between IP fax packets can vary greatly depending upon a state of the session. With reference to FIG. 3, an illustrative sequence of packets in an exemplary fax transmission 300 is shown in which consecutive fax packets are transmitted having varying time intervals associated therewith. For example, a first fax packet 302 (packet n−1) is transmitted at time t, a second fax packet 304 (packet n) is transmitted at time t+T1, a third fax packet 306 (packet n+1) is transmitted at time t+T1+T2, a fourth fax packet 308 (packet n+2) is transmitted at time t+T1+T2+T3, and so on. As apparent from the figure, however, the time intervals T1, T2, and T3 are not equal relative to one another. Therefore, a receiver of the T.38 packets (e.g., receive fax machine 214 in FIG. 2) is not able to determine when a packet is lost since a large time gap/interval (e.g., greater than about 100 milliseconds (ms)) between packets may be normal in a T.30/T.38 FoIP session.
Because of this inherent inconsistency between the respective time intervals of consecutively transmitted fax packets 302, 304, 306, 308 in a given FoIP session (attributable at least in part to the nature of the IP network), two new types of packets are introduced in an error correction scheme according to an embodiment of the invention; namely, an “idle” packet and a “retransmit request” packet, as will be described in further detail below.
An idle packet, which may be implemented, for example, using a t30-indicator message in the context of a T.38 protocol, is employed to keep packet transmission from one gateway to another gateway in time intervals that are not greater than a prescribed (i.e., negotiated, for example, via signaling protocols such as, but not limited to, Session Initiation Protocol (SIP)/Session Description Protocol (SDP), H.248 or H.323) value. According to the Abstract Syntax Notation One (ASN.1) in Annex A of ITU-T T.38, Internet Fax Protocol (IFP) packets are essentially comprised of two fields. A first field is used to identify the type of IFP packet as either t30-indicator or t30-data. A second field, if required, contains payload data. t30-indicator messages are used to indicate when fax signals have been detected while t30-data messages are used to transfer blocks of data.
Note, that the “keep-alive” (or watchdog) function of the idle packets may sometimes be also performed by t30-indicator packets defined in T.38. For example, when a gateway first detects a V.17 carrier from the PSTN, it sends a v17 training indicator to its peer gateway. Because there is a training period (e.g., greater than about 500 ms) between the carrier detection and the receipt of the first byte of data, the gateway may send the idle packets in time intervals that are not greater than the prescribed (or negotiated) value. Alternatively, the gateway can also keep sending the v17 training indicator in the pre-defined (negotiated) time interval. A purpose of this keep-alive (or watchdog) scheme is to enable gateways to detect packet losses and to know when to request for retransmission of lost or potentially lost packets.
FIG. 4 is a block diagram depicting at least a portion of an exemplary fax transmission stream 400 in which one or more idle packets are inserted into the sequence of packets such that each packet interval is substantially the same relative to one another, according to an embodiment of the invention. Specifically, with reference again to FIG. 3, the time interval between the transmission of the first fax packet 302 (n−1) and the second fax packet 304 (n) is T1 (assuming that T1 is the pre-defined or negotiated maximum allowed packet interval). However, the time interval between transmission of the second fax packet 304 and the third fax packet 306 (n+1) is T2, with interval T2 being substantially greater than interval T1 (e.g., about three times greater). In this instance, the fax receiver may assume that a fax packet has been lost.
In order to address this problem, FIG. 4 shows the insertion of two idle packets, 402 (packet n+1) and 404 (packet n+2), between the second fax packet 304 and the third fax packet, reordered as fifth fax packet 406 (packet n+3), with the time interval between consecutive packets being less than or equal to T1. Likewise, in order to fill the time gap T3 between the transmission of fax packets 306 and 308 in FIG. 3, time interval T3 being greater than time interval T1, an idle packet 408 (packet n+4) is preferably inserted between the fifth fax packet 406 and the fourth fax packet 308 in FIG. 3, reordered as seventh fax packet 410 (packet n+5), with the time interval between consecutive packets being less than or equal to T1. Thus, idle packets will be sent (e.g., inserted into a fax transmission sequence by the transmit gateway 206 in FIG. 2) with valid sequence numbers periodically when there is no data available from the transmit fax apparatus or PSTN (e.g., 202 or 204, respectively, in FIG. 2). This enables a T.38 receive gateway/ATA (e.g., 210 in FIG. 2) to detect delay or loss of T.38 packets sent from the peer T.38 gateway/ATA (e.g., 206 in FIG. 2).
It is to be understood that the number of idle packets inserted between two otherwise consecutive fax data packets is not limited by the invention. Rather, the number of idle packets inserted into the sequence will be dependent upon the length of the time interval between transmitted fax data packets. For example, in the transmission of consecutive fax packets 304 and 406, since time interval T2 (shown in FIG. 3) is about three times greater than time interval T1, three packets total (including fax packet 304 and two idle packets 402 and 404) are inserted between the start of transmission of packet 304 and the start of transmission of packet 406. Conversely, in the transmission of consecutive fax packets 406 and 410, since time interval T3 (shown in FIG. 3) is only about twice T1, two packets total (including fax packet 406 and one idle packet 408) are inserted between the start of transmission of packet 406 and the start of transmission of packet 410. Furthermore, although the packets are preferably sent in substantially equal (e.g., fixed) time intervals T1, the invention is not limited to any specific value for the time intervals.
In contrast to an idle packet described above, a retransmit request packet is preferably operative to store sequence numbers of missing packets. The retransmit request packet may be implemented, for example, using a t30-data message in the context of a T.38 protocol. The sequence numbers of missing packets may be embedded in the payload data of the t30-data message. When a plurality of missed packets are detected that are consecutive in sequence number, only the sequence numbers of a start and an end of the missing packets need to be specified and stored. A retransmit request packet will preferably be sent when the receive gateway (e.g., 210 in FIG. 2) detects a loss, or potential loss, of one or more fax packets. In accordance with aspects of the invention, a user may control criteria for determining packet loss (or potential packet loss) and for sending retransmit request packets, for example in conjunction with jitter buffer management methodologies.
In one illustrative embodiment, requesting retransmission of a fax packet may be initiated by checking the sequence number of arriving packets, including idle packets, and sending out a retransmit request packet to the T.38 transmit gateway (e.g., 206 in FIG. 2) whenever a gap in the sequence number between consecutively received packets is detected. This methodology maybe performed, for example, in the T.38 receive gateway (e.g., 210 in FIG. 2). Alternatively, the methodology can be performed in other devices, such as, but not limited to, IP-aware fax machines and ATAs. The sequence number, or an alternative identifier by which a temporal sequence of a given data packet in a stream may be indicated, can be included, for example, in a header or a payload data portion of the packet, as will become apparent to those skilled in the art given the teachings herein. The receive fax apparatus (e.g., 214 in FIG. 2) may, alternatively, wait a prescribed period of time for out-of-order packets before sending the retransmit request packet to the transmit gateway.
A receiver of retransmit request packets (e.g., transmit gateway) will preferably check the availability of the requested packets and retransmit these packets immediately or within a prescribed period of time after receiving the retransmit request if the missed/requested packet is still available. Determining whether or not the requested/missing data packet(s) is(are) available for retransmission may involve, for example, comparing a first sequence identification (e.g., sequence number) of a data packet stored in the second gateway (e.g., in a transmit buffer) with a second sequence identification of an identified missing data packet. When the requested packet is no longer available, the gateway/ATA that receives the retransmit request packet may simply ignore the request.
The availability of the requested packets depends, at least in part, on a size of a transmit buffer, or other storage element, associated with the gateways and/or the time at which the retransmit request packet is received. The transmit buffer, which may be implemented, for example, using a circular buffer, stores previously transmitted packets. When a new packet is transmitted, a copy of the packet will preferably be stored in the transmit buffer for retransmission and error correction purposes, if necessary; in the meantime, the oldest packet in the transmit buffer will be pushed out or overwritten when all other storage locations in the buffer are filled. A gateway may inform the peer gateway of its transmit buffer size, for example, during call setup via signaling protocols (e.g., SIP/SDP, H.248, H.323, etc), or by alternative means. When the gateway sending a retransmit request does not receive the retransmitted packets within a prescribed period of time, it may assume that the packets are not recoverable and proceed to process the next available packets.
By way of example only and without loss of generality, FIG. 5 depicts at least a portion of an illustrative data transfer 500 between a transmit gateway 206 and a receive gateway 210 during a FoIP session, according to an embodiment of the invention. As apparent from the figure, at least the first three data packets, with sequence numbers Seq#1 through Seq#3, sent by the transmit gateway 206 are received by the receive gateway 210 in the proper order, as indicated by arrows 502, 504 and 506. However, data packets with sequence number from n to n+k transmitted by transmit gateway 206 are lost due to some error (e.g., burst error) attributable to, for example, the transmit gateway 206, the receive gateway 210, and/or the communications channel 508 established between the transmit and receive gateways, as indicated by dotted arrows 510 through 514. The next data packet actually received by the receive gateway 210 is the data packet with sequence number n+k+1, which is assumed to be non-consecutive in relation to the data packet with sequence number Seq#3, as indicated by arrow 516.
The receive gateway 210 detects the packet loss and, after storing (e.g., in memory associated with the receive gateway) the data packet with sequence number n+k+1, sends a retransmission request for the lost packets, as indicated by arrow 518. The retransmission request preferably includes the sequence number of the lost data packet (or sequence numbers if multiple lost data packets are detected). Assuming a copy of the requested packets are still available, transmit gateway 206 will retransmit the requested lost packets, preferably in a burst mode in order to recover the packets in a shorter period of time. In burst mode, a plurality of requested data packets, as identified in the retransmission request, are sent in relatively quick succession compared to a normal transfer rate of the fax data packets. Retransmission of the requested data packets is indicated by arrows 520 through 524.
If the retransmitted packets are still not received by the receive gateway 210 within a prescribed period of time (and are thus presumed lost), another retransmission request may be sent by the receive gateway 210 to the transmit gateway 206. A limit to the number of retransmission attempts may be set by a user (e.g., maximum of two retransmission attempts); otherwise, packet retransmission may interfere with the normal transmission of packet sequences by the transmit gateway 206. Alternatively, if the retransmitted packets are not received, an error message may be sent by the receive gateway 210 or the lost data packets may be simply ignored, at which processing continues with the next received packet.
Once retransmission of the missing data packets is complete (either successfully or unsuccessfully), the transmit gateway 206 preferably resumes normal transmission of the data packets using the next sequence number, n+k+2, following the sequence number of the last data packet that was successfully received (e.g., Seq#n+k+1), as indicated by arrow 526.
In certain instances in which packets are sent out in a substantially regular time interval, the insertion of idle packets into the packet stream may not be required during image data transfer. Moreover, it is possible to apply this error correction scheme only for the image data transfer mode (e.g., Phase C—image transfer and message transmission—of a T.30 fax session), according to embodiments of the invention. In this case, idle packets are not required.
As previously stated, error correction techniques according to the invention may be combined with one or more known error correction schemes (e.g., redundancy and/or FEC, in the context of a T.38 protocol) to obtain further advantages during a given FoIP session. For example, one can employ both redundancy error correction and ROD in a T.38-based FoIP session, in accordance with an aspect of the invention.
Methodologies of embodiments of the present invention may be particularly well-suited for implementation in an electronic device or alternative system, such as, for example, a network-capable fax device, fax communications system, etc. By way of illustration only, FIG. 6 is a block diagram depicting an exemplary data processing system 600, formed in accordance with an aspect of the invention. System 600 may represent, for example, a fax device (e.g., fax modem, fax machine, etc.) adapted for communicating with a PC and/or another fax device using, for example, a G3 and/or a T.38 communications protocol. System 600 may include a processor 602, memory 604 coupled to the processor, as well as input/output (I/O) circuitry 608 operative to interface with the processor. The processor 602, memory 604, and I/O circuitry 608 can be interconnected, for example, via a bus 606, or alternative connection means, as part of data processing system 600. Suitable interconnections, for example via the bus, can also be provided to a network interface 610, such as a network interface card (NIC), which can be provided to interface with a computer or IP network, and to a media interface, such as a diskette or CD-ROM drive, which can be provided to interface with media. The processor 602 may be configured to perform at least a portion of the methodologies of the present invention described herein above.
It is to be appreciated that the term “processor” as used herein is intended to include any processing device, such as, for example, one that includes a central processing unit (CPU) and/or other processing circuitry (e.g., network processor, DSP, microprocessor, etc.). Additionally, it is to be understood that the term “processor” may refer to more than one processing device, and that various elements associated with a processing device may be shared by other processing devices. The term “memory” as used herein is intended to include memory and other computer-readable media associated with a processor or CPU, such as, for example, random access memory (RAM), read only memory (ROM), fixed storage media (e.g., a hard drive), removable storage media (e.g., a diskette), flash memory, etc. Furthermore, the term “I/O circuitry” as used herein is intended to include, for example, one or more input devices (e.g., keyboard, mouse, etc.) for entering data to the processor, one or more output devices (e.g., printer, monitor, etc.) for presenting the results associated with the processor, and/or interface circuitry for operatively coupling the input or output device(s) to the processor.
Accordingly, an application program, or software components thereof, including instructions or code for performing the methodologies of the invention, as described herein, may be stored in one or more of the associated storage media (e.g., ROM, fixed or removable storage) and, when ready to be utilized, loaded in whole or in part (e.g., into RAM) and executed by the processor 602. In any case, it is to be appreciated that at least a portion of the components shown in FIGS. 1 and 2 may be implemented in various forms of hardware, software, or combinations thereof, e.g., one or more DSPs with associated memory, application-specific integrated circuit(s), functional circuitry, one or more operatively programmed general purpose digital computers with associated memory, etc. Given the teachings of the invention provided herein, one of ordinary skill in the art will be able to contemplate other implementations of the components of the invention.
At least a portion of the techniques of the present invention may be implemented in one or more integrated circuits. In forming integrated circuits, die are typically fabricated in a repeated pattern on a surface of a semiconductor wafer. Each of the die includes a memory described herein, and may include other structures or circuits. Individual die are cut or diced from the wafer, then packaged as integrated circuits. One skilled in the art would know how to dice wafers and package die to produce integrated circuits. Integrated circuits so manufactured are considered part of this invention.
An IC in accordance with embodiments of the present invention can be employed in any application and/or electronic system which is adapted for providing fax communications (e.g., fax modem/machine). Suitable systems for implementing embodiments of the invention may include, but are not limited to, personal computers, portable communications devices (e.g., cell phones), fax devices, etc. Systems incorporating such integrated circuits are considered part of this invention. Given the teachings of the invention provided herein, one of ordinary skill in the art will be able to contemplate other implementations and applications of the techniques of the invention.
Although illustrative embodiments of the present invention have been described herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various other changes and modifications may be made therein by one skilled in the art without departing from the scope of the appended claims.
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Error detection/correction and fault detection/recovery
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stats Patent Info
Application #
US 20120110403 A1
Publish Date
05/03/2012
Document #
12917635
File Date
11/02/2010
USPTO Class
714748
Other USPTO Classes
714E11113
International Class
/
Drawings
5
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Error Detection/correction And Fault Detection/recovery Pulse Or Data Error Handling Digital Data Error Correction Request For Retransmission
|
__label__pos
| 0.781589 |
Download MetaTrader 5
Fastest way to change profiles?
To add comments, please log in or register
Piplover
39
Piplover
Please tell me there is a faster method of changing profiles than, File; Profile; Find and select. Please oh please say there is.
It would be great if the Currency pairs were easily changeable and the Profile remained the same. I don't know but any thing faster than this situation.
rv
461
rv
PipLover:
Please tell me there is a faster method of changing profiles than, File; Profile; Find and select. Please oh please say there is.
It would be great if the Currency pairs were easily changeable and the Profile remained the same. I don't know but any thing faster than this situation.
in the status bar (bottom of metatrader) you see the default profile.
so, create your own profile with same charts and different TF's.
Click there in the status bar and change anytime
qjol
3243
qjol
or a script
PostMessageA(hndl, WM_COMMAND, 34100, 0); // for the first profile
PostMessageA(hndl, WM_COMMAND, 34101, 0); // for the second & so on
Piplover
39
Piplover
Thank you very much!
Ickyrus
873
Ickyrus
PipLover:
It would be great if the Currency pairs were easily changeable and the Profile remained the same. I don't know but any thing faster than this situation.
You can select drag and drop any currency pair on to a chart - instant currency change and chart set up stays the same.
qjol
3243
qjol
Ickyrus:
You can select drag and drop any currency pair on to a chart - instant currency change and chart set up stays the same.
or using a template
Lee
9
Lee
I have many profile, each for different analysis purposes; each profile have many charts windows inside. The issue is it's time consuming to change different market, like from eurusd to usdjpy for example, into the same profile; each time I have to drag and drop many times, very time consuming and non productive!
Is there any way to write a script or code to do this with just one action, or a click?
Any script help with filling many chart windows with one market?
Thank you for your help with code and further instructions as I am new to mql4.
Thank a lots.
Lee
Ubzen
5394
Ubzen
Is there any way to write a script or code to do this with just one action, or a click?
Yes, if you have the programming skills. But you wouldn't be asking if you did. Your best bet is to Pay for an experienced programmer to built.
Lee
9
Lee
Thanks Ubzen for quick instruction,
Frankly, I can not write any code. I just refer to job markets as your instructed, very exciting and economically efficient and I agree letting specialized guys to go the jobs better than learning abc while have no programming background.
However, can you or any other fellow could help me out this time? I want to have a feel of how an automatic piece work in mt4. I assume this job is a simple task?
Let be straight to me guys.
Thanks,
Lee
Ubzen
5394
Ubzen
I assume this job is a simple task?
No, it's not a simple task. I don't have the skills to manipulate Windows. For those who have the skills, it'll take Hours not Minutes to program this from scratch (unless they're super-programmer IMO). If someone have already programmed this before + it meets what you're looking for exactly (un-likely) + they're willing to give it to you for free, then you're in luck.
Lee
9
Lee
Thanks indeed Ubzen!
Lee
12
To add comments, please log in or register
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__label__pos
| 0.792293 |
MegaWidget MegaWidget - 4 months ago 12
Android Question
Passing "this" as root to LayoutInflater.inflate() in a custom component
I am writing the code for a custom component that extends LinearLayout. It will include a Spinner at the top, and some number of settings below, depending on what the Spinner is set to. i.e., when the user selects "Apple" on the spinner, a "color" option appears, and when they select "Banana" a "length" option appears.
Since a spinner option might have many settings associated with it, I define each group of settings in a layout XML with "merge" as the root tag. Then I call initViews() in each constructor to inflate the views so I can add/remove them later.
Here is the code for the class:
public class SchedulePickerView extends LinearLayout {
protected Context context;
protected Spinner typeSpinner;
protected ViewGroup defaultSetters; // ViewGroup to show when no schedule is selected in the spinner
protected ViewGroup simpleSetters; // ViewGroup to show when SimpleSchedule is selected in the spinner
public SchedulePickerView(Context context) {
super(context);
this.context = context;
initViews();
}
public SchedulePickerView(Context context, AttributeSet attr) {
super(context, attr);
this.context = context;
initViews();
}
public SchedulePickerView(Context context, AttributeSet attr, int defstyle) {
super(context, attr, defstyle);
this.context = context;
initViews();
}
private void initViews() {
// Init typeSpinner
typeSpinner = (Spinner) findViewById(R.id.schedulepickerSpinner);
// Init setters (ViewGroups that show settings for the various types of schedules
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
// ERROR IS ON THIS LINE:
defaultSetters = inflater.inflate(R.layout.container_schedulesetter_default, this);
}
}
I get this error on the marked line: "Incompatible types: Required = ViewGroup, Found = View". But LinearLayout extends ViewGroup, as per this documentation. I have even tried casting "this" to a ViewGroup, but strangely the IDE greyed-out the cast (since, obviously, every LinearLayout is already a ViewGroup). So why is there an issue?
Answer
inflate() returns a View and you're trying to assign it to a more specific ViewGroup variable. It's not the this as parent view that is problematic - you need a cast on the return value:
defaultSetters = (ViewGroup)inflater.inflate(...)
|
__label__pos
| 0.995698 |
How do I annotate a document?
Annotations are graphic markers and review remarks you can add to a document preview. You can place annotations in a document preview wherever you want them. For example, using annotations you can add a pushpin marker to a document preview, and enter a comment about the document right where the pushpin is placed. Each person's annotations appear in a unique color, making it easy to follow who said what.
1. Open the document preview (see How do I view a file?).
Note: Document previews are limited to the first 100 pages of a document.
2. Select a tool from the Tools menu.
Table 7-1 Annotation Tools
Tool Usage
None
Select None when you want to move through the document without annotating text.
Pushpin tool
Use the Pushpin tool to post an annotation to a pinpointed location.
Pen tool
Use the Pen tool to create a free-form mark on the material you're annotating.
Highlighter tool
Use the Highlighter tool to highlight one line of the material you're annotating.
Rectangle tool
Use the Rectangle tool to draw a rectangle over the material you're annotating.
Ellipse tool
Use the Ellipse tool to draw a circle over the material you're annotating.
Notes:
• The icon to the left of the Tools menu shows the tool that is currently selected.
• If you don't see the Tools menu at the top of a document on a person's wall, the person does not allow other people to post annotations to his or her personal documents.
3. Click or highlight the text you want to annotate.
• For the pushpin, click the location you want to annotate.
• For the drawing tools, drag them to surround or highlight the text you want to annotate. Drawing tools include the pen, the highlighter, the rectangle, and the ellipse.
A dialog opens where you can enter your remarks.
4. In the dialog, enter a remark.
5. Click Continue to continue annotating the document.
6. When you're finished adding annotations, at the top of the preview, click Publish.
Example 7-1 Associating Multiple Annotations
You can mark several disconnected sections of text and combine them into a single annotation. After adding the first mark, with the annotation box still open, use the selected tool to make additional marks on the same page (you can't join marks on multiple pages). After you add an annotation message and click Continue, the application draws a larger box around all the marks, and ties the single annotation message to all of them.
|
__label__pos
| 0.871393 |
Solved
Need Word Macro to Find and Change Entire Line to Style
Posted on 2016-07-21
6
70 Views
Last Modified: 2016-07-21
Need a macro that would find Sub in the below example, highlight the rest of line (it can include the word Sub) and then
change the style to Heading 2. It need it to run until it reaches the end of the document.
Sub InsertPics()
Dim fd As FileDialog
Dim rng As Range
Dim ilsh As InlineShape
0
Comment
Question by:Alex Campbell
[X]
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• 4
6 Comments
LVL 31
Accepted Solution
by:
Helen Feddema earned 500 total points
ID: 41723826
I have a Word macro that does this (and a lot more). I use it to format code for readability. I just copy a procedure, paste it into a document made from the template, and it applies formatting to the entire procedure. Here is the code, which you could paste into a new template and modify as needed.
Sub Test()
Debug.Print "Docs path: " & Options.DefaultFilePath(wdDocumentsPath)
Debug.Print "Current path: " & Options.DefaultFilePath(wdCurrentFolderPath)
Debug.Print "Template path: " & Options.DefaultFilePath(wdUserTemplatePath)
End Sub
Sub FormatCode()
'Created 03-26-1997 by Helen Feddema
'Last modified 11-10-2003
Dim strTitle As String
Dim strFindText As String
Dim strReplaceText As String
Dim rngSave As Range
Dim strApostrophe As String
Dim lngEnd As Long
Dim rngEnd As Range
Dim varPosition As Variant
With Selection
.WholeStory
.Style = ActiveDocument.Styles("Code")
.HomeKey Unit:=wdStory
.Find.ClearFormatting
.Find.Replacement.ClearFormatting
End With
'Insert page breaks between procedures
strFindText = "^pSub"
strReplaceText = "^p^mSub"
Selection.Find.ClearFormatting
Selection.Find.Replacement.ClearFormatting
With Selection.Find
.Text = strFindText
.Replacement.Text = strReplaceText
.Forward = True
.Wrap = wdFindContinue
.Format = False
End With
Selection.Find.Execute Replace:=wdReplaceAll
strFindText = strFindText
strReplaceText = "^p^mPrivate Sub"
Selection.Find.ClearFormatting
Selection.Find.Replacement.ClearFormatting
With Selection.Find
.Text = "^pPrivate Sub"
.Replacement.Text = strReplaceText
.Forward = True
.Wrap = wdFindContinue
.Format = False
End With
Selection.Find.Execute Replace:=wdReplaceAll
strFindText = "^pFunction"
strReplaceText = "^p^mFunction"
Selection.Find.ClearFormatting
Selection.Find.Replacement.ClearFormatting
With Selection.Find
.Text = strFindText
.Replacement.Text = strReplaceText
.Forward = True
.Wrap = wdFindContinue
.Format = False
End With
Selection.Find.Execute Replace:=wdReplaceAll
strFindText = "^pProperty Get"
strReplaceText = "^p^mProperty Get"
Selection.Find.ClearFormatting
Selection.Find.Replacement.ClearFormatting
With Selection.Find
.Text = strFindText
.Replacement.Text = strReplaceText
.Forward = True
.Wrap = wdFindContinue
.Format = False
End With
Selection.Find.Execute Replace:=wdReplaceAll
strFindText = "^pProperty Let"
strReplaceText = "^p^mProperty Let"
Selection.Find.ClearFormatting
Selection.Find.Replacement.ClearFormatting
With Selection.Find
.Text = strFindText
.Replacement.Text = strReplaceText
.Forward = True
.Wrap = wdFindContinue
.Format = False
End With
Selection.Find.Execute Replace:=wdReplaceAll
strFindText = "^pProperty Set"
strReplaceText = "^p^mProperty Set"
Selection.Find.ClearFormatting
Selection.Find.Replacement.ClearFormatting
With Selection.Find
.Text = strFindText
.Replacement.Text = strReplaceText
.Forward = True
.Wrap = wdFindContinue
.Format = False
End With
Selection.Find.Execute Replace:=wdReplaceAll
strFindText = "^pPublic Function"
strReplaceText = "^p^mPublic Function"
Selection.Find.ClearFormatting
Selection.Find.Replacement.ClearFormatting
With Selection.Find
.Text = strFindText
.Replacement.Text = strReplaceText
.Forward = True
.Wrap = wdFindContinue
.Format = False
End With
Selection.Find.Execute Replace:=wdReplaceAll
strFindText = "^pPublic Sub"
strReplaceText = "^p^mPublic Sub"
Selection.Find.ClearFormatting
Selection.Find.Replacement.ClearFormatting
With Selection.Find
.Text = strFindText
.Replacement.Text = strReplaceText
.Forward = True
.Wrap = wdFindContinue
.Format = False
End With
Selection.Find.Execute Replace:=wdReplaceAll
strFindText = "^pPrivate Function"
strReplaceText = "^p^mPrivate Function"
Selection.Find.ClearFormatting
Selection.Find.Replacement.ClearFormatting
With Selection.Find
.Text = strFindText
.Replacement.Text = strReplaceText
.Forward = True
.Wrap = wdFindContinue
.Format = False
End With
Selection.Find.Execute Replace:=wdReplaceAll
'Format procedure headings with Heading 2 style
Set rngSave = Selection.Range
Selection.HomeKey Unit:=wdStory
strFindText = "^p^mSub"
With Selection.Find
.ClearFormatting
.Execute findtext:=strFindText
While .Found = True
Selection.EndKey Unit:=wdLine, Extend:=wdExtend
Selection.Style = ActiveDocument.Styles("Heading 2")
Selection.MoveRight
.Execute
Wend
rngSave.Select
End With
strFindText = "^p^mPrivate Sub"
With Selection.Find
.ClearFormatting
.Execute findtext:=strFindText
While .Found = True
Selection.EndKey Unit:=wdLine, Extend:=wdExtend
Selection.Style = ActiveDocument.Styles("Heading 2")
Selection.MoveRight
.Execute
Wend
rngSave.Select
End With
strFindText = "^p^mFunction"
With Selection.Find
.ClearFormatting
.Execute findtext:=strFindText
While .Found = True
Selection.EndKey Unit:=wdLine, Extend:=wdExtend
Selection.Style = ActiveDocument.Styles("Heading 2")
Selection.MoveRight
.Execute
Wend
rngSave.Select
End With
strFindText = "^p^mProperty"
With Selection.Find
.ClearFormatting
.Execute findtext:=strFindText
While .Found = True
Selection.EndKey Unit:=wdLine, Extend:=wdExtend
Selection.Style = ActiveDocument.Styles("Heading 2")
Selection.MoveRight
.Execute
Wend
rngSave.Select
End With
strFindText = "^p^mPublic Function"
With Selection.Find
.ClearFormatting
.Execute findtext:=strFindText
While .Found = True
Selection.EndKey Unit:=wdLine, Extend:=wdExtend
Selection.Style = ActiveDocument.Styles("Heading 2")
Selection.MoveRight
.Execute
Wend
rngSave.Select
End With
strFindText = "^p^mPublic Sub"
With Selection.Find
.ClearFormatting
.Execute findtext:=strFindText
While .Found = True
Selection.EndKey Unit:=wdLine, Extend:=wdExtend
Selection.Style = ActiveDocument.Styles("Heading 2")
Selection.MoveRight
.Execute
Wend
rngSave.Select
End With
strFindText = "^p^mPrivate Function"
With Selection.Find
.ClearFormatting
.Execute findtext:=strFindText
While .Found = True
Selection.EndKey Unit:=wdLine, Extend:=wdExtend
Selection.Style = ActiveDocument.Styles("Heading 2")
Selection.MoveRight
.Execute
Wend
rngSave.Select
End With
'Apply Label style to labels
strFindText = ":^p"
With Selection.Find
.ClearFormatting
.Execute findtext:=strFindText
While .Found = True
Selection.HomeKey Unit:=wdLine
Selection.EndKey Unit:=wdLine, Extend:=wdExtend
Selection.Style = ActiveDocument.Styles("Label")
Selection.MoveRight Unit:=wdCharacter, Count:=1
.Execute
Wend
rngSave.Select
End With
'Apply Comment style to comments
strFindText = Chr$(39)
With Selection.Find
.ClearFormatting
.Execute findtext:=strFindText
While .Found = True
'Test whether apostrophe is not at beginning of line
varPosition = _
Selection.Information(wdHorizontalPositionRelativeToTextBoundary)
'Debug.Print "Position of apostrophe: " & varPosition
If varPosition < 140 Then
Selection.EndKey Unit:=wdLine, Extend:=wdExtend
Selection.Style = ActiveDocument.Styles("Comment")
Selection.MoveRight Unit:=wdCharacter, Count:=1
.Execute
Else
Selection.MoveRight Unit:=wdCharacter, Count:=1
.Execute
End If
Wend
rngSave.Select
End With
'Format document heading with Heading 2 style
Selection.EndKey Unit:=wdLine, Extend:=wdExtend
Selection.Style = ActiveDocument.Styles("Heading 2")
Selection.MoveLeft Unit:=wdCharacter, Count:=1, Extend:=wdExtend
strTitle = Selection
If ActiveWindow.View.SplitSpecial <> wdPaneNone Then
ActiveWindow.Panes(2).Close
End If
If ActiveWindow.ActivePane.View.Type = wdNormalView Or ActiveWindow. _
ActivePane.View.Type = wdOutlineView Or ActiveWindow.ActivePane.View.Type _
= wdMasterView Then
ActiveWindow.ActivePane.View.Type = wdPageView
End If
'Suggest document title, and save user's choice to Title field
If ActiveDocument.BuiltInDocumentProperties("Title") = "None" Then
If Left(strTitle, 23) <> "Option Compare Database" Then
ActiveDocument.BuiltInDocumentProperties("Title") = strTitle
Else
strTitle = InputBox(prompt:="Please enter the document name", Title:="Document Name", Default:="___ Form Module")
ActiveDocument.BuiltInDocumentProperties("Title") = strTitle
Selection.HomeKey Unit:=wdLine
Selection.MoveDown Unit:=wdLine, Count:=3, Extend:=wdExtend
Selection.Delete Unit:=wdCharacter, Count:=1
Selection.TypeText Text:=strTitle
Selection.TypeParagraph
End If
End If
End Sub
Open in new window
I am also attaching the template, in case you want to try it. To use it, first copy the code to the clipboard, then make a new document from template; it will ask if you want to import the code from the clipboard -- say Yes. Then run the FormatCode macro to do the formatting. (I put it on the Quick Access Toolbar.)
0
LVL 31
Expert Comment
by:Helen Feddema
ID: 41723828
The .dotm extension wasn't accepted; I tried using a zip file with it inside, but that was rejected too. If you want the template emailed to you, send me a message with your email.
0
LVL 32
Expert Comment
by:Paul Sauvé
ID: 41723898
you can use ee-stuff.com to upload blocked files using your E-E creds to login: https://www.ee-stuff.com/
To upload:
select Experts Area ―> Upload a new file ―> Question or Article URL ―> upload file
To download:
select Experts Area ―> Find files for a question ―> Question URL ―> download file
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On Demand Webinar: Networking for the Cloud Era
Ready to improve network connectivity? Watch this webinar to learn how SD-WANs and a one-click instant connect tool can boost provisions, deployment, and management of your cloud connection.
LVL 31
Expert Comment
by:Helen Feddema
ID: 41723915
I uploaded the template to ee-stuff.
0
LVL 31
Expert Comment
by:Helen Feddema
ID: 41723930
Here is a screen shot of a page of formatted code:
Formatted code
0
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Author Closing Comment
by:Alex Campbell
ID: 41723940
Very good. Thanks
0
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| 0.815853 |
Tutorial: Window.setAsForeground
Window.setAsForeground
Will bring the window to the front of the entire stack and give it focus
Example
async function createWin() {
const app = await fin.Application.start({
name: 'myApp',
uuid: 'app-1',
url: 'https://cdn.openfin.co/docs/javascript/stable/tutorial-Window.setAsForeground.html',
autoShow: true
});
return await app.getWindow();
}
async function setAsForeground() {
const win = await createWin();
return await win.setAsForeground()
}
setAsForeground().then(() => console.log('In the foreground')).catch(err => console.log(err));
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tech on the net
MS Excel: Refresh multiple pivot tables with a button in Excel 2003/XP/2000/97
Learn how to refresh multiple pivot tables with a button in (other versions of Excel):
Question: In Microsoft Excel 2003/XP/2000/97, is it possible to create a button that will refresh/update multiple pivot tables?
Answer: Yes, you can refresh multiple pivot tables with a button. To do this:
Under the View menu, select Toolbars > Forms.
Microsoft Excel
Create a button in your spreadsheet using the Forms toolbar. To do this, click on the button icon (currently highlighted in picture below) and click on your spreadsheet where you would like the button to appear.
Microsoft Excel
After creating the button, the Assign Macro window should appear. Click on the "New" button.
Microsoft Excel
Then paste in similar code as below in the Button_Click event:
Sheets("Sheet1").Select
ActiveSheet.PivotTables("PivotTable1").RefreshTable
Sheets("Sheet2").Select
ActiveSheet.PivotTables("PivotTable2").RefreshTable
Microsoft Excel
You will need to replace the Sheet1 and Sheet2 with the names of your sheets and PivotTable1 and PivotTable2 with the names of your pivot tables.
To find out the name of a pivot table, right-click on the pivot table and select Table Options.
Microsoft Excel
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Oracle® Fusion Middleware Java EE Developer's Guide for Oracle Application Development Framework
11g Release 1 (11.1.1.6.0)
Part Number E16272-04
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4 Creating ADF Databound Tables
This chapter describes how to use the Data Controls panel to create basic databound tables that are based on ADF Faces components, including editable tables and input tables.
This chapter includes the following sections:
4.1 Introduction to Adding Tables
Unlike forms, tables allow you to display more than one data object from a collection returned by an accessor at a time. Figure 4-1 shows a table on the browse page of the Suppliers module, with the products returned from the search.
Figure 4-1 Results Table Displays Products That Match the Search Criteria
The browse page contains a table that lists products
You can create tables that simply display data, or you can create tables that allow you to edit or create data. Once you drop an accessor as a table, you can add command buttons bound to actions that execute some logic on a selected row. You can also modify the default components to suit your needs.
4.2 Creating a Basic Table
Unlike with forms where you bind the individual UI components that make up a form to the individual attributes on the collection, with a table you bind the ADF Faces table component to the complete collection or to a range of n data objects at a time from the collection. The individual components used to display the data in the columns are then bound to the attributes. The iterator binding handles displaying the correct data for each object, while the table component handles displaying each object in a row. JDeveloper allows you to do this declaratively, so that you don't need to write any code.
4.2.1 How to Create a Basic Table
To create a table using a data control, you bind the table component to a returned collection. JDeveloper allows you to do this declaratively by dragging and dropping a collection from the Data Controls panel.
Tip:
You can also create a table by dragging a table component from the Component Palette and completing the Create ADF Faces Table wizard. For more information, see the "How to Display a Table on a Page" section of the Oracle Fusion Middleware Web User Interface Developer's Guide for Oracle Application Development Framework.
To create a databound table:
1. From the Data Controls panel, select a collection.
For example, to create a simple table in the Suppler module that displays products in the system, you would select the productFindAll accessor collection.
2. Drag the collection onto a JSF page, and from the context menu, choose the appropriate table.
When you drag the collection, you can choose from the following types of tables:
• ADF Table: Allows you to select the specific attributes you need your editable table columns to display, and what UI components to use to display the data. By default, ADF inputText components are used for most attributes, thus enabling the table to be editable. Attributes that are dates use the inputDate component. Additionally, if a control type control hint has been created for an attribute, or if the attribute has been configured to be a list, then the component set by the hint is used instead. For more information about setting control hints, see the "Defining Attribute Control Hints for View Objects" section of the Oracle Fusion Middleware Fusion Developer's Guide for Oracle Application Development Framework
• ADF Read-Only Table: Same as the ADF Table; however, each attribute is displayed in an outputText component.
• ADF Read-Only Dynamic Table: Allows you to create a table when the attributes returned and displayed are determined dynamically at runtime. This component is helpful when the attributes for the corresponding object are not known until runtime, or you do not wish to hardcode the column names in the JSF page.
3. The ensuing Edit Table Columns dialog shows each attribute in the collection, and allows you to determine how these attributes will behave and appear as columns in your table.
Note:
If the collection contains a structured attribute (an attribute that is neither a Java primitive type nor a collection), the attributes of the structured attributes will also appear in the dialog.
Using this dialog, you can do the following:
• Allow the ADF Model layer to handle selection by selecting the Row Selection checkbox. Selecting this option means that the iterator binding will access the iterator to determine the selected row. Select this option unless you do not want the table to allow selection.
• Allow the ADF Model layer to handle column sorting by selecting the Sorting checkbox. Selecting this option means that the iterator binding will access the iterator, which will perform an order-by query to determine the order. Select this option unless you do not want to allow column sorting.
• Allow the columns in the table to be filtered using entered criteria by selecting the Filtering checkbox. Selecting this option allows the user to enter criteria in text fields above each column. That criteria is then used to build a Query-by-Example (QBE) search on the collection, so that the table will display only the results returned by the query. For more information, see Section 7.5, "Creating Standalone Filtered Search Tables."
• Group columns for selected attributes together under a parent column, by selecting the desired attributes (shown as rows in the dialog), and clicking the Group button. Figure 4-2 shows how two grouped columns appear in the visual editor after the table is created.
Figure 4-2 Grouped Columns in an ADF Faces Table
You can group columns together
• Change the display label for a column by entering text or an EL expression to bind the label value to something else, for example, a key in a resource file. By default, the label is bound to the labels property for any control hint defined for the attribute on the table binding. This binding allows you to change the value of a label text one time in the structure file, and have the change propagate to all pages that display the label.
• Change the value binding for a column by selecting a different attribute to bind to. If you simply want to rearrange the columns, you should use the order buttons. If you do change the attribute binding for a column, the label for the column also changes.
• Change the UI component used to display an attribute using the dropdown menu. The UI components are set based on the table you selected when you dropped the collection onto the page, on the type of the corresponding attribute (for example, inputDate components are used for attributes that are dates), and on whether or not default components were set as control hints in the Java class's structure file.
Tip:
If one of the attributes for your table is also a primary key, you may want to choose a UI component that will not allow a user to change the value.
Tip:
If you want to use a component that is not listed in the dropdown menu, use this dialog to select the outputText component, and then manually add the other tag to the page.
• Change the order of the columns using the order buttons.
• Add a column using the Add icon. There's no limit to the number of columns you can add. When you first click the icon, JDeveloper adds a new column line at the bottom of the dialog and populates it with the values from the first attribute in the bound collection; subsequent new columns are populated with values from the next attribute in the sequence, and so on.
• Delete a column using the Delete icon.
4. Once the table is dropped on the page, you can use the Property Inspector to set other display properties of the table. For example, you may want to set the width of the table to a certain percentage or size. For more information about display properties, see the "Using Tables and Trees" chapter of the Oracle Fusion Middleware Web User Interface Developer's Guide for Oracle Application Development Framework.
Tip:
When you set the table width to 100%, the table will not include borders, so the actual width of the table will be larger. To have the table set to 100% of the container width, expand the Style section of the Property Inspector, select the Box tab, and set the Border Width attribute to 0 pixels.
5. If you want the user to be able to edit information in the table and save any changes, you need to provide a way to submit and persist those changes. For more information, see Section 4.3, "Creating an Editable Table." For procedures on creating tables that allow users to input data, see Section 4.4, "Creating an Input Table."
4.2.2 What Happens When You Create a Table
Dropping a table from the Data Controls panel has the same effect as dropping a text field or form. Briefly, JDeveloper does the following:
• Creates the bindings for the table and adds the bindings to the page definition file
• Adds the necessary code for the UI components to the JSF page
For more information, see Section 3.2.2, "What Happens When You Create a Text Field."
4.2.2.1 Iterator and Value Bindings for Tables
When you drop a table from the Data Controls panel, a tree value binding is created. A tree consists of a hierarchy of nodes, where each subnode is a branch off a higher level node. In the case of a table, it is a flattened hierarchy, where each attribute (column) is a subnode off the table. Like an attribute binding used in forms, the tree value binding references the accessor iterator binding, while the accessor iterator binding references the iterator for the data control, which facilitates iterating over the data objects in the collection. Instead of creating a separate binding for each attribute, only the tree binding to the table node is created. In the tree binding, the AttrNames element within the nodeDefinition element contains a child element for each attribute that you want to be available for display or reference in each row of the table.
The tree value binding is an instance of the FacesCtrlHierBinding class that extends the core JUCtrlHierBinding class to add two JSF specific properties:
• collectionModel: Returns the data wrapped by an object that extends the javax.faces.model.DataModel object that JSF and ADF Faces use for collection-valued components like tables.
• treeModel: Extends collectionModel to return data that is hierarchical in nature. For more information, see Chapter 5, "Displaying Master-Detail Data."
Example 4-1 shows the value binding for the table created when you drop the productFindAll accessor collection. For simplicity, only a few of the attributes from the collection are shown.
Example 4-1 Value Binding Entries for a Table in the Page Definition File
<bindings>
<tree IterBinding="productFindAllIterator" id="productFindAll">
<nodeDefinition DefName="oracle.fodemo.supplier.model.Product">
<AttrNames>
<Item Value="productId"/>
<Item Value="productName"/>
<Item Value="costPrice"/>
<Item Value="listPrice"/>
<Item Value="minPrice"/>
<Item Value="productStatus"/>
<Item Value="shippingClassCode"/>
<Item Value="warrantyPeriodMonths"/>
</AttrNames>
</nodeDefinition>
</tree>
</bindings>
Only the table component needs to be bound to the model (as opposed to the columns or the text components within the individual cells), because only the table needs access to the data. The tree binding for the table drills down to the individual structure attributes in the table, and the table columns can then derive their information from the table component.
4.2.2.2 Code on the JSF Page for an ADF Faces Table
When you use the Data Controls panel to drop a table onto a JSF page, JDeveloper inserts an ADF Faces table component, which contains an ADF Faces column component for each attribute named in the table binding. Each column then contains another component (such as an inputText or outputText component) bound to the attribute's value. Each column's heading is bound to the labels property for the control hint of the attribute.
Tip:
If an attribute is marked as hidden in the associated structure file, no corresponding UI is created for it.
Example 4-2 shows a simplified code excerpt from a table created by dropping the productFindAll accessor collection as a read-only table.
Example 4-2 Simplified JSF Code for an ADF Faces Table
<af:table value="#{bindings.productFindAll.collectionModel}" var="row"
rows="#{bindings.productFindAll.rangeSize}"
emptyText="#{bindings.productFindAll.viewable ? 'No data to display.' :
'Access Denied.'}"
fetchSize="#{bindings.productFindAll.rangeSize}"
rowBandingInterval="0" id="t1">
<af:column sortProperty="productId" sortable="false"
headerText="#{bindings.productFindAll.hints.productId.label}"
id="c1">
<af:outputText value="#{row.productId}" id="ot8">
<af:convertNumber groupingUsed="false"
pattern="#{bindings.productFindAll.hints.productId.format}"/>
</af:outputText>
</af:column>
<af:column sortProperty="productName" sortable="false"
headerText="#{bindings.productFindAll.hints.productName.label}"
id="c4">
<af:outputText value="#{row.productName}" id="ot7"/>
</af:column>
. . .
</af:table>
The tree binding iterates over the data exposed by the iterator binding. Note that the table's value is bound to the collectionModel property, which accesses the collectionModel object. The table wraps the result set from the iterator binding in a collectionModel object. The collectionModel allows each item in the collection to be available within the table component using the var attribute.
In the example, the table iterates over the rows in the current range of the productFindAll accessor binding. This binding binds to a row set iterator that keeps track of the current row. When you set the var attribute on the table to row, each column then accesses the current data object for the current row presented to the table tag using the row variable, as shown for the value of the af:outputText tag:
<af:outputText value="#{row.productId}"/>
When you drop an ADF Table (as opposed to an ADF Read-Only Table), instead of being bound to the row variable, the value of the input component is implicitly bound to a specific row in the binding container through the bindings property, as shown in Example 4-3. Additionally, JDeveloper adds validator and converter components for each input component. By using the bindings property, any raised exception can be linked to the corresponding binding object or objects. The controller iterates through all exceptions in the binding container and retrieves the binding object to get the client ID when creating FacesMessage objects. This retrieval allows the table to display errors for specific cells. This strategy is used for all input components, including selection components such as lists.
Example 4-3 Using Input Components Adds Validators and Converters
<af:table value="#{bindings.productFindAll.collectionModel}" var="row"
rows="#{bindings.productFindAll.rangeSize}"
emptyText="#{bindings.productFindAll.viewable ? 'No data to display.'
: 'Access Denied.'}"
fetchSize="#{bindings.productFindAll.rangeSize}"
rowBandingInterval="0"
selectedRowKeys="#{bindings.productFindAll1.collectionModel.selectedRow}"
selectionListener="#{bindings.productFindAll1.collectionModel.
makeCurrent}"
rowSelection="single"
filterModel="#{bindings.productFindAllQuery.queryDescriptor}"
queryListener="#{bindings.productFindAllQuery.processQuery}"
filterVisible="true" varStatus="vs" id="t1">
<af:column sortProperty="productId" sortable="false"
headerText="#{bindings.productFindAll.hints.productId.label}"
id="c5">
<af:inputText value="#{row.bindings.productId.inputValue}"
label="#{bindings.productFindAll.hints.productId.label}"
required="#{bindings.productFindAll.hints.productId.mandatory}"
columns="#{bindings.productFindAll.hints.productId.displayWidth}"
maximumLength="#{bindings.productFindAll.hints.productId.precision}"
shortDesc="#{bindings.productFindAll.hints.productId.tooltip}"
id="it4">
<f:validator binding="#{row.bindings.productId.validator}"/>
<af:convertNumber groupingUsed="false"
pattern="#{bindings.productFindAll.hints.productId.format}"/>
</af:inputText>
</af:column>
. . .
</af:table>
For more information about using ADF Faces validators and converters, see the "Validating and Converting Input" chapter of the Oracle Fusion Middleware Web User Interface Developer's Guide for Oracle Application Development Framework.
Table 4-1 shows the other attributes defined by default for ADF Faces tables created using the Data Controls panel.
Table 4-1 ADF Faces Table Attributes and Populated Values
Attribute Description Default Value
rows
Determines how many rows to display at one time.
An EL expression that, by default, evaluates to the rangeSize property of the associated iterator binding, which determines how many rows of data are fetched from a data control at one time. Note that the value of the rows attribute must be equal to or less than the corresponding iterator's rangeSize value, as the table cannot display more rows than are returned. For more information about the rangeSize property, see Section 3.4.2.2, "Iterator RangeSize Attribute."
emptyText
Text to display when there are no rows to return.
An EL expression that evaluates to the viewable property on the iterator. If the table is viewable, the attribute displays No data to display when no objects are returned. If the table is not viewable (for example, if there are authorization restrictions set against the table), it displays Access Denied.
fetchSize
Number of rows of data fetched from the data source.
An EL expression that, by default, evaluates to the rangeSize property of the associated iterator binding. For more information about the rangeSize property, see Section 3.4.2.2, "Iterator RangeSize Attribute." This attribute can be set to a larger number than the rows attribute.
selectedRowKeys
The selection state for the table.
An EL expression that, by default, evaluates to the selected row on the collection model.
selectionListener
Reference to a method that listens for a selection event.
An EL expression that, by default, evaluates to the makeCurrent method on the collection model.
rowSelection
Determines whether rows are selectable.
Set to single to allow one row to be selected at a time.
Column Attributes
sortProperty
Determines the property by which to sort the column.
Set to the column's corresponding attribute binding value.
sortable
Determines whether a column can be sorted.
Set to false. When set to true, the iterator binding will access the iterator to determine the order.
headerText
Determines the text displayed at the top of the column.
An EL expression that, by default, evaluates to the label control hint set on the corresponding attribute.
4.2.3 What You May Need to Know About Setting the Current Row in a Table
When you use tables in an application and you allow the ADF Model layer to manage row selection, the current row is determined by the iterator. When a user selects a row in an ADF Faces table, the row in the table is shaded, and the component notifies the iterator of the selected row. To do this, the selectedRowKeys attribute of the table is bound to the collection model's selected row, as shown in Example 4-4.
Example 4-4 Selection Attributes on a Table
<af:table value="#{bindings.Products1.collectionModel}" var="row"
.
.
.
selectedRowKeys="#{bindings.Products.collectionModel.selectedRow}"
selectionListener="#{bindings.Products.collectionModel.
makeCurrent}"
rowSelection="single">
This binding binds the selected keys in the table to the selected row of the collection model. The selectionListener attribute is then bound to the collection model's makeCurrent property. This binding makes the selected row of the collection the current row of the iterator.
Note:
If you create a custom selection listener, you must create a method binding to the makeCurrent property on the collection model (for example, #{binding.Products.collectionModel.makeCurrent}) and invoke this method binding in the custom selection listener before any custom logic.
Although a table can handle selection automatically, there may be cases where you need to programmatically set the current row for an object on an iterator.
You can call the getKey() method on any view row to get a Key object that encapsulates the one or more key attributes that identify the row. You can also use a Key object to find a view row in a row set using the findByKey(). At runtime, when either the setCurrentRowWithKey or the setCurrentRowWithKeyValue built-in operation is invoked by name by the data binding layer, the findByKey() method is used to find the row based on the value passed in as a parameter before the found row is set as the current row.
The setCurrentRowWithKey and setCurrentRowWithKeyValue operations both expect a parameter named rowKey, but they differ precisely by what each expects that rowKey parameter value to be at runtime:
The setCurrentRowWithKey Operation
setCurrentRowWithKey expects the rowKey parameter value to be the serialized string representation of a view row key. This is a hexadecimal-encoded string that looks like this:
000200000002C20200000002C102000000010000010A5AB7DAD9
The serialized string representation of a key encodes all of the key attributes that might comprise a view row's key in a way that can be conveniently passed as a single value in a browser URL string or form parameter. At runtime, if you inadvertently pass a parameter value that is not a legal serialized string key, you may receive exceptions like oracle.jbo.InvalidParamException or java.io.EOFException as a result. In your web page, you can access the value of the serialized string key of a row by referencing the rowKeyStr property of an ADF control binding (for example. #{bindings.SomeAttrName.rowKeyStr}) or the row variable of an ADF Faces table (for example, #{row.rowKeyStr}).
setCurrentRowWithKeyValue
The setCurrentRowWithKeyValue operation expects the rowKey parameter value to be the literal value representing the key of the view row. For example, its value would be simply "201" to find product number 201.
4.3 Creating an Editable Table
You can create a table that allows the user to edit information within the table, and then commit those changes to the data source. To do this, you use operations that can modify data records associated with the returned collection (or the data control itself) to create command buttons, and place those buttons in a toolbar in the table. For example, the table in the browse.jspx page has a button that allows the user to remove a product. While this button currently causes a dialog to display that allows the user to confirm the removal, the button could be bound to a method that directly removes the product.
Tip:
To create a table that allows you to insert a new record into the data store, see Section 4.4, "Creating an Input Table."
As with editable forms, it is important to note that the ADF Model layer is not aware that any row has been changed until a new instance of the collection is presented. Therefore, you need to invoke the execute operation on the accessor iterator in order for any changes to be committed. For more information, see Section 2.3.4, "What You May Need to Know About Iterator Result Caching."
When you decide to use editable components to display your data, you have the option of having the table displaying all rows as editable at once, or having it display all rows as read-only until the user double-clicks within the row. Figure 4-3 shows a table whose rows all have editable fields. The page is rendered using the components that were added to the page (for example, inputText, inputDate, and inputNumberSpinbox components).
Figure 4-3 Table with Editable Fields
Table with editable fields
Figure 4-2 shows the same table, but configured so that the user must double-click (or single-click if the row is already selected) a row in order to edit or enter data. Note that outputText components are used to display the data in the nonselected rows, even though the same input components as in Figure 4-3 were used to build the page. The only row that actually renders those components is the row selected for editing.
Figure 4-4 Click to Edit a Row
click to edit a row
For more information about how ADF Faces table components handle editing, see the "Editing Data in Tables, Trees, and Tree Tables" section of the Oracle Fusion Middleware Web User Interface Developer's Guide for Oracle Application Development Framework.
4.3.1 How to Create an Editable Table
To create an editable table, you follow procedures similar to those for creating a basic table, then you add command buttons bound to operations. However, in order for the table to contain a toolbar, you need to add an ADF Faces component that associates the toolbar with the items in the collection used to build the table.
To create an editable table:
1. From the Data Controls panel, select the collection to display in the table.
For example, to create a simple table in the Suppliers module that will allow you to edit suppliers in the system, you would select the supplierFindAll accessor collection.
2. Drag the accessor onto a JSF page, and from the context menu, choose ADF Table.
3. Use the ensuing Edit Table Columns dialog to determine how the attributes should behave and appear as columns in your table. Be sure to select the Row Selection checkbox, which will allow the user to select the row to edit.
For more information about using this dialog to configure the table, see Section 4.2, "Creating a Basic Table."
4. With the table selected in the Structure window, expand the Behavior section of the Property Inspector and set the EditingMode attribute. If you want all the rows to be editable select editAll. If you want the user to click into a row to make it editable, select clickToEdit.
5. From the Structure window, right-click the table component and select Surround With from the context menu.
6. In the Surround With dialog, ensure that ADF Faces is selected in the dropdown list, select the Panel Collection component, and click OK.
The panelCollection component's toolbar facet will hold the toolbar which, in turn, will hold the command components used to update the data.
7. In the Structure window, right-click the panelCollection's toolbar facet folder, and from the context menu, choose Insert inside toolbar > Toolbar.
This creates a toolbar that already contains a default menu which allows users to change how the table is displayed, and a Detach link that detaches the entire table and displays it such that it occupies the majority of the space in the browser window. For more information about the panelCollection component, see the "Displaying Table Menus, Toolbars, and Status Bars" section of the Oracle Fusion Middleware Web User Interface Developer's Guide for Oracle Application Development Framework.
8. From the Data Controls panel, select the method or operation associated with the collection of objects on which you wish to execute the logic, and drag it onto the toolbar component in the Structure window. This will place the databound command component inside the toolbar.
For example, if you want to be able to remove a supplier record, you would drag the removeSuppliers(Suppliers) method. Figure 4-5 shows the remove methods in the Suppliers module.
Figure 4-5 Operations Associated with a Collection
Navigation operations in the DCP
9. For the context menu, choose Operations > ADF Toolbar Button.
Because the method takes parameters, the Action Binding Editor opens, asking you to set the value of the parameters.
10. In the Edit Action Binding dialog, you need to populate the value for the method's parameter. For the remove methods (and the other default methods), this is the selected object.
1. In the Parameters section, use the Value dropdown list to select Show EL Expression Builder.
2. In the Expression Builder, expand the node for the accessor's iterator, then expand the currentRow node, and select dataProvider.
This will create an EL expression that evaluates to the data for the current row in the accessor's iterator.
3. Click OK.
For example, if you created a table using the suppliersFindAll accessor, then JDeveloper would have created an accessorIterator binding named suppliersFindAllIterator. You would need to select the dataProvider object for the current row under that iterator, as shown in Figure 4-8. This reference means that the parameter value will resolve to the value of the currently selected row.
Figure 4-6 dataProvider for the Current Row on the suppliersFindAllIterator Binding
dataProvider for Current Row on suppliersFindAllIterator
11. To notify the ADF Model layer that the collection has been modified, you need to also bind the toolbar button to a method that will refresh the iterator.
1. Open the page definition for the JSPX file by right-clicking the file and choosing Go to Page Definition.
2. In the Structure Window for the page definition, right-click bindings and choose Insert inside bindings > Generic Bindings > action.
3. In the Create Action Binding dialog, use the Select an Iterator dropdown list to select the iterator associated with the collection, and for Operation, select Execute.
JDeveloper creates an action binding for the execute operation of the iterator. You now need to have your command button call this operation.
12. In the JSF page, select the command component created when you dropped the method in Step 10. In the Property Inspector, set Action to the following:
#{bindings.Execute.execute}
When the command component is clicked, the binding to the action attribute is evaluated after the binding for the actionListener attribute. This order ensures iterator refreshes and/or executes after the deletion of entity.
4.3.2 What Happens When You Create an Editable Table
Creating an editable table is similar to creating a form used to edit records. Action bindings are created for the operations dropped from the Data Controls panel. For more information, see Section 3.6.2, "What Happens When You Use Methods to Change Data."
4.4 Creating an Input Table
You can create a table that allows users to insert a new blank row into a table and then add values for each column (any default values set on the corresponding entity object will be automatically populated).
4.4.1 How to Create an Input Table
When you create an input table, you want the user to see the new blank row in the context of the other rows within the current row set. To allow this insertion, you need to use the create operation associated with the accessor for the collection. For example, to create a table that allows users to create new suppliers, you would create a table from the supplierFindAll accessor collection and then add a button using the create operation for the supplierFindAll accessor collection.
Because the create operation only creates a row in the cache, you also need to add a button that actually merges the newly created row into the collection. Figure 4-7 shows how this table might look with a new row created.
Figure 4-7 User Can Create Suppliers in This Input Table
Table shows suppliers
ADF Faces components can be set so that one component refreshes based on an interaction with another component, without the whole page needing to be refreshed. This is known as partial page rendering. When the user clicks the button to create the new row, you want the table to refresh to display that new row. To have that happen, you need to configure the table to respond to that user action.
Before you begin:
You need to create an editable table, as described in Section 4.3, "Creating an Editable Table."
To create an input table:
1. From the Data Controls panel, drag the create operation associated with the dropped collection and drop it as a toolbar button into the toolbar.
Tip:
You may want to change the ID to something more recognizable, such as Create. This will make it easier to identify when you need to select it as the partial trigger.
2. In the Structure window, select the table component.
3. In the Property Inspector, expand the Behavior section, click the dropdown menu for the PartialTriggers attribute, and select Edit.
4. In the Edit Property dialog, expand the toolbar facet for the panelCollection component and then expand the toolbar that contains the Create command component. Select that component and shuttle it to the Selected panel. Click OK. This sets that component to be the trigger that will cause the table to refresh.
5. Create a button that allows the user to merge the new object(s) into the collection. From the Data Controls panel, drag the merge method associated with the collection used to create the table, and drop it as a toolbar button or link into the toolbar.
Tip:
If you will want the user to be able to continue updating the row after it is persisted, then you should create the button using the persist method instead. For more information, see Section 3.6.3, "What You May Need to Know About the Difference Between the Merge and Persist Methods."
Figure 4-8 shows merge method for the Suppliers collection.
Figure 4-8 Merge Methods in the Data Controls Panel
The Commit operation is nested under the Operators folder.
4.4.2 What Happens When You Create an Input Table
When you use the create operation to create an input table, JDeveloper:
• Creates an iterator binding for the collection, an action binding for the create operation, and attribute bindings for the table. The create operation is responsible for creating the new row in the row set. If you created command buttons or links using the merge method, JDeveloper also creates an action binding for that method.
• Inserts code in the JSF page for the table for the ADF Faces components.
Example 4-5 shows the page definition file for an input table created from the Supplier collection (some attributes were deleted in the Edit Columns dialog when the collection was dropped).
Example 4-5 Page Definition Code for an Input Table
<executables>
<variableIterator id="variables"/>
<iterator Binds="root" RangeSize="25" DataControl="SessionEJBLocal"
id="SessionEJBLocalIterator"/>
<accessorIterator MasterBinding="SessionEJBLocalIterator"
Binds="suppliersFindAll" RangeSize="25"
DataControl="SessionEJBLocal" BeanClass="model.Suppliers"
id="suppliersFindAllIterator"/>
</executables>
<bindings>
<action IterBinding="suppliersFindAllIterator" id="Create"
RequiresUpdateModel="true" Action="createRow"/>
<methodAction id="mergeSuppliers" RequiresUpdateModel="true"
Action="invokeMethod" MethodName="mergeSuppliers"
IsViewObjectMethod="false" DataControl="SessionEJBLocal"
InstanceName="SessionEJBLocal.dataProvider"
ReturnName="SessionEJBLocal.methodResults.mergeSuppliers_
SessionEJBLocal_dataProvider_mergeSuppliers_result">
<NamedData NDName="suppliers"
NDValue="#{bindings.Create.currentRow.dataProvider}"
NDType="model.Suppliers"/>
</methodAction>
<tree IterBinding="suppliersFindAllIterator" id="suppliersFindAll">
<nodeDefinition DefName="model.Suppliers">
<AttrNames>
<Item Value="email"/>
<Item Value="phoneNumber"/>
<Item Value="supplierId"/>
<Item Value="supplierName"/>
<Item Value="supplierStatus"/>
</AttrNames>
</nodeDefinition>
</tree>
</bindings>
Example 4-6 shows the code added to the JSF page that provides partial page rendering, using the Create Supplier and Commit New Suppliers command toolbar button as the triggers to refresh the table.
Example 4-6 Partial Page Trigger Set on a Command Button for a Table
<af:form id="f1">
<af:panelCollection id="pc1">
<f:facet name="menus"/>
<f:facet name="toolbar">
<af:toolbar id="t2">
<af:commandToolbarButton actionListener="#{bindings.Create.execute}"
text="Create New Supplier"
disabled="#{!bindings.Create.enabled}"
id="ctb1"/>
<af:commandToolbarButton
actionListener="#{bindings.mergeSuppliers.execute}"
text="Commit New Suppliers"
disabled="#{!bindings.mergeSuppliers.enabled}"
id="ctb2"/>
</af:toolbar>
</f:facet>
<f:facet name="statusbar"/>
<af:table value="#{bindings.suppliersFindAll.collectionModel}"
var="row" rows="#{bindings.suppliersFindAll.rangeSize}"
emptyText="#{bindings.suppliersFindAll.viewable ? 'No data to
display.' : 'Access Denied.'}"
fetchSize="#{bindings.suppliersFindAll.rangeSize}"
rowBandingInterval="0"
selectedRowKeys=
"#{bindings.suppliersFindAll.collectionModel.selectedRow}"
selectionListener=
"#{bindings.suppliersFindAll.collectionModel.makeCurrent}"
rowSelection="single" id="t1"
partialTriggers="::ctb1 ::ctb2">
<af:column sortProperty="supplierId" sortable="false"
headerText=
"#{bindings.suppliersFindAll.hints.supplierId.label}"
id="c6">
<af:inputText value="#{row.bindings.supplierId.inputValue}"
label="#{bindings.suppliersFindAll.hints.supplierId.label}"
required="#{bindings.suppliersFindAll.hints.supplierId.mandatory}"
columns="#{bindings.suppliersFindAll.hints.supplierId.displayWidth}"
maximumLength="#{bindings.suppliersFindAll.hints.supplierId.precision}"
shortDesc="#{bindings.suppliersFindAll.hints.supplierId.tooltip}"
id="it4">
<f:validator binding="#{row.bindings.supplierId.validator}"/>
<af:convertNumber groupingUsed="false"
pattern="#{bindings.suppliersFindAll.hints.supplierId.format}"/>
</af:inputText>
</af:column>
.
.
.
</af:table>
</af:panelCollection>
</af:form>
4.4.3 What Happens at Runtime: How Create and Partial Page Refresh Work
When the button bound to the create operation is invoked, the action executes, and a new instance for the collection is created as the page is rerendered. Because the button was configured to be a trigger that causes the table to refresh, the table redraws with the new empty row shown at the top. When the user clicks the button bound to the merge method, the newly created rows in the row set are inserted into the database. For more information about partial page refresh, see the "Rendering Partial Page Content" chapter in the Oracle Fusion Middleware Web User Interface Developer's Guide for Oracle Application Development Framework.
4.4.4 What You May Need to Know About Creating a Row and Sorting Columns
If your table columns allow sorting, and the user has sorted on a column before inserting a new row, then that new row will not be sorted. To have the column sort with the new row, the user must first sort the column opposite to the desired sort, and then re-sort. This is because the table assumes the column is already sorted, so clicking on the desired sort order first will have no effect on the column.
For example, say a user had sorted a column in ascending order, and then added a new row. Initially, that row appears at the top. If the user first clicks to sort the column again in ascending order, the table will not re-sort, as it assumes the column is already in ascending order. The user must first sort on descending order and then ascending order.
If you want the data to automatically sort on a specific column in a specific order after inserting a row, then programmatically queue a SortEvent after the commit, and implement a handler to execute the sort.
4.5 Modifying the Attributes Displayed in the Table
Once you use the Data Controls panel to create a table, you can then delete attributes, change the order in which they are displayed, change the component used to display them, and change the attribute binding for the component. You can also add new attributes, or rebind the table to a new data control.
For more information about modifying existing UI components and bindings, see the "Modifying the Attributes Displayed in the Table" section of the Oracle Fusion Middleware Fusion Developer's Guide for Oracle Application Development Framework.
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Operaciones combinadas
Anuncios patrocinados
Publicado en: Educación, Escuela, Manuales, Matemática
| 11 junio, 2012 | 9 Comentarios
Las operaciones combinadas son aquellas en las cuales aparecen varias operaciones aritméticas para resolver. Pero para obtener el resultado correcto es necesario seguir algunas reglas y tener en cuenta la prioridad entre las operaciones.
En primer lugar siempre se van a separar los términos presentes para luego poder resolver cada uno de estos. Luego vamos a resolver todas las operaciones que se encuentres entre paréntesis, corchetes y llaves, hay que tener en cuenta que si el paréntesis va precedido del signo + se va a suprimir y mantendrán su signo los términos que contenga, en cambio, si el paréntesis va precedido del signo -, cuando se suprima el paréntesis debemos cambiar el signo a todos los términos que contenga.
Para poder resolver las operaciones combinadas, tenemos que seguir un orden específico:
1- En primer lugar potenciación y radicación.
2- Luego la multiplicación y división de fracciones en el orden en el cual aparecen.
3- Por último las sumas y restas, resolviendo las sumas y las restas que separan los términos en el orden en el cual aparecen.
Por ejemplo si la operación es la siguiente:
9 − 7 + 5 + 2 − 6 + 8 − 4 =
Para resolver esto efectuaremos las operaciones según aparecen comenzando por la izquierda a lo cual nos quedaría la siguiente resolución:
9 − 7 + 5 + 2 − 6 + 8 − 4 = 7 sería el resultado final
Ahora si por ejemplo tenemos sumas, restas y multiplicaciones, Realizaremos en primer lugar los productos (en esta caso las multiplicaciones), ya que estos tienen mayor prioridad, continuo a esto efectuaremos las sumas y restas:
3 • 2 − 5 + 4 • 3 − 8 + 5 • 2 =
6 − 5 + 12 − 8 + 10 =
6 − 5 + 12 − 8 + 10 = 15
Y en el caso de tener también divisiones, resolveremos primero las multiplicaciones y cocientes, y por último las sumas y restas.
¿Se entiende? No es muy complejo, quizás se dificulta cuando también tenemos potencias. En este caso efectuaremos en primer lugar las potencias, las cuales en este caso tienen mayor prioridad, a continuación realizaremos los productos y cocientes dejando por ultimo las sumas y restas. Y si la operación de complejiza más y además de sumas, restas, multiplicaciones, divisiones y potencias tenemos paréntesis; en primer lugar resolveremos las operaciones que se encuentran encerradas entre estos, y después quitaremos los paréntesis, realizando el resto de las operaciones:
Y si a todo esto se le suman los corchetes, resolveremos primero las potencias, productos y cocientes que se encuentren dentro de los paréntesis. Realizaremos luego las suma y restas de los paréntesis, resuelto esto podemos usar paréntesis directamente y no corchetes. Luego resolveremos lo que quedó incluido en los paréntesis. Multiplicaremos, restaremos y sumaremos. El siguiente es un ejemplo claro:
Si nuestra operación tiene fracciones, primero debemos proceder a realizar los productos y números mixtos que se encuentren dentro de los paréntesis. Luego de esto se realizará una simplificación. Realizando siempre en primer lugar las operaciones dentro del paréntesis. Por último se realizaran las operaciones del numerador, dividiendo y luego simplificando el resultado.
Si aún no te quedó claro, te dejo un último ejemplo para que despejes tus dudas
Vía: matematica.laguia2000.com
Etiquetas: , , , , , operaciones combinadas resueltas, operaciones combinadas concepto, operaciones combinadas resueltas primaria, operaciones combinadas con vectores y ejemplos, operaciones combinadas de vectores ejemplos, ejercicios resueltos con opetaciones combinadas con vectores
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Manage Assets
In this example, we will show you how to use the CreativeEditor SDK's CreativeEngine to manage assets through the asset API.
To begin working with assets first you need at least one asset source. As the name might imply asset sources provide the engine with assets. These assets then show up in the editor's asset library. But they can also be independently searched and used to create design blocks. Asset sources can be added dynamically using the asset API as we will show in this guide.
Explore a full code sample of the integration on CodeSandbox or view the code on GitHub.
Setup#
This example uses the headless CreativeEngine. See the Setup article for a detailed guide. To get started right away, you can also access the block API within a running CE.SDK instance via cesdk.engine.block. Check out the APIs Overview to see that illustrated in more detail.
Defining a Custom Asset Source#
Asset sources need at least an id and a findAssets function. You may notice asset source functions are all async. This way you can use web requests or other long-running operations inside them and return results asynchronously.
Let's go over these properties one by one:
All functions of the asset API refer to an asset source by its unique id. That's why it has to be mandatory. Trying to add an asset source with an already registered id will fail.
• findAssets(sourceId: string, query: AssetQueryData): Promise<AssetsQueryResult> should return paginated asset results for the given queryData. The asset results have a set of mandatory and optional properties. For a listing with an explanation for each property please refer to the Integrate a Custom Asset Source guide. The properties of the queryData and the pagination mechanism are also explained in this guide.
• applyAsset?: (asset: AssetResult) => Promise<void> is an optional function to define the behavior of what to do when an asset gets applied to the scene. You can use the engine's APIs to do whatever you want with the given asset result. In this case, we always create an image block and add it to the first page we find.
If you don't provide this function the engine's default behavior is to create a block based on the asset result's meta.blockType property, add the block to the active page, and sensibly position and size it.
• applyAssetToBlock?: (asset: AssetResult, block: number) => Promise<void> is an optional function to define the behavior of what to do when an asset gets applied to an existing block. You can use the engine's APIs to do whatever you want with the given asset result. Here we just trigger the default engine behavior.
If you don't provide this function the engine's default behavior is to update the block's source uri based on the asset result's meta.blockType property. For blocks with a corresponding property meta.previewUri is also taken into account.
Registering a New Asset Source#
• addSource(source: AssetSource): void now allows registering our custom asset source with the engine.
• findAllSources(): string[] lists all available sources including our newly registered asset source 'foobar'.
• removeSource(id: string): void allows removing our source. We do this at the very end. But it is not necessary.
Finding and Applying Assets#
• findAssets(sourceId: string, query: AssetQueryData): Promise<AssetsQueryResult> can be used after registering our custom source to obtain a search result. We want an asset from the first page (indexing starts at 0) and at most 100 asset results for that query.
• async apply(sourceId: string, assetResult: AssetResult): Promise<void> Finally, we can apply the first asset result from our query result to the scene using apply. The custom applyAsset function of our asset source will run to do this job.
File:
import CreativeEngine from 'https://cdn.img.ly/packages/imgly/cesdk-engine/1.9.2/index.js';
const config = {
baseURL: 'https://cdn.img.ly/packages/imgly/cesdk-engine/1.9.2/assets'
};
CreativeEngine.init(config).then(async (engine) => {
const scene = engine.scene.create();
const page = engine.block.create('page');
engine.block.appendChild(scene, page);
const customSource = {
id: 'foobar',
async findAssets(queryData) {
return Promise.resolve({
assets: [
{
id: 'logo',
thumbUri: 'https://img.ly/static/ubq_samples/thumbnails/imgly_logo.jpg',
size: {
width: 320,
height: 116
},
meta: {
uri: 'https://img.ly/static/ubq_samples/imgly_logo.jpg',
blockType: 'ly.img.image'
},
context: {
sourceId: 'foobar'
}
}
],
total: 1,
currentPage: queryData.page,
nextPage: undefined
});
},
async applyAsset(assetResult) {
const image = engine.block.create('image');
engine.block.setString(image, 'image/imageFileURI', assetResult.meta.uri);
engine.block.setWidth(image, assetResult.size.width);
engine.block.setHeight(image, assetResult.size.height);
const firstPage = engine.block.findByType('page')[0];
engine.block.appendChild(firstPage, image);
engine.block.setWidth(firstPage, assetResult.size.width);
engine.block.setHeight(firstPage, assetResult.size.height);
engine.scene.zoomToBlock(firstPage, 0, 0, 0, 0);
engine.editor.addUndoStep();
},
async applyAssetToBlock(assetResult, block) {
engine.asset.defaultApplyAssetToBlock(assetResult, block);
}
};
engine.asset.addSource(customSource);
engine.asset.findAllSources()
const result = await engine.asset.findAssets(customSource.id, {page: 0, perPage: 100});
const asset = result.assets[0];
await engine.asset.apply(customSource.id, asset);
engine.asset.removeSource(customSource.id);
});
|
__label__pos
| 0.964875 |
読者です 読者をやめる 読者になる 読者になる
【swift】無限スクロールするUItableViewを実装する方法メモ
swift iPhoneアプリ開発
はじめに
今回やりたかったのは、またありがちなこんな感じの画面です。
f:id:yoppy0066:20150903080226j:plain
といってもやりたかったのは、こちらで書いた内容をコードレベルにしたもので。
【swift】uitableviewが重いときに対処すべき2つのこと - とりあえずphpとか
UITableViewを使うときにパフォーマンス面で気をつけるということでした（なめらかになるにしたかった）
あとは、行によってテーブルセルの高さを動的に変更することでしょうか
上の記事とかぶりますがやっぱり以下がポイントかとおもいます
・１度高さを計算した行は何度も計算し直さない
・セルの高さ計算用のオブジェクトを用意して使い回す
実装方法
ViewController.swift
class ViewController: UIViewController, UITableViewDelegate, UITableViewDataSource
{
var tableView: UITableView = UITableView()
var tableData = [Dictionary<String, AnyObject>]()
// API等からデータを取得するためのクラス
var model: Model = Model()
// セルの高さ計算用のテーブルセル ★ここがポイント
var calcCell = CustomTableViewCell()
// セルの高さ保持用の配列 ★ここがポイント
var cacheCellHeight = [CGFloat]()
// 読み込み中フラグ
var isLoading: Bool = false
override func viewDidLoad()
{
super.viewDidLoad()
// データ取得
self.isLoading = true
model.get { (result) -> Void in
self.callback(result)
}
// VIEWをセットします
setView()
}
// VIEWをセットします
func setView()
{
// ・・・
//テーブルビューのおきまりの処理とか
tableView.registerClass(CustomTableViewCell.self, forCellReuseIdentifier: "CustomCell")
self.view.addSubview(tableView)
}
func callback(result: [Dictionary<String,AnyObject>])
{
for var i = 0; i < result.count; i++ {
self.tableData.insert(result[i], atIndex: self.tableData.count)
}
self.isLoading = false
self.tableView.reloadData()
}
// 1番したまでスクロールしたらデータ取得
func scrollViewDidScroll(scrollView: UIScrollView)
{
var contentOffsetWidthWindow = self.tableView.contentOffset.y + self.tableView.bounds.size.height
var eachToBottom = contentOffsetWidthWindow >= self.tableView.contentSize.height
if (!eachToBottom || self.isLoading) {
return;
}
self.isLoading = true
model.get { (result) -> Void in
self.callback(result)
}
}
// テーブルセルの高さをかえします ★ここがポイント
func tableView(tableView: UITableView, heightForRowAtIndexPath indexPath: NSIndexPath) -> CGFloat
{
if cacheCellHeight.count - 1 >= indexPath.row {
return cacheCellHeight[indexPath.row]
} else {
var height = self.calcCell.setData(tableData[indexPath.row])
cacheCellHeight.insert(height, atIndex: indexPath.row)
return height
}
}
// テーブルの行数をかえします
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int
{
return self.tableData.count
}
}
CustomTableViewCell.swift
カスタムテーブルビューセルで画面にデータをセットすることと、高さをかえすのが役割
class CustomTableViewCell: UITableViewCell
{
var icon = UIImageView()
var title = UILabel()
var content = UILabel()
override init(style: UITableViewCellStyle, reuseIdentifier: String!)
{
super.init(style: style, reuseIdentifier: reuseIdentifier)
self.setUp()
}
required init(coder aDecoder: NSCoder)
{
super.init(coder: aDecoder)
self.setUp()
}
func setUp()
{
self.addSubview(icon)
self.addSubview(title)
self.addSubview(content)
}
// データをセットして高さを返します
func setData(data: Dictionary<String,AnyObject>) -> CGFloat
{
var widthMax: CGFloat = self.frame.width
var heightMax: CGFloat = self.frame.height
icon.frame = CGRectMake(5, 5, 48, 48)
icon.image = UIImage(named: data["icon"] as! String)
title.frame = CGRectMake(icon.frame.origin.x + icon.frame.size.width + 5, 5, widthMax - (5 + icon.frame.size.width + 5 + 5), 20)
title.font = UIFont.boldSystemFontOfSize(15)
title.text = data["name"] as? String
content.frame = CGRectMake(title.frame.origin.x, title.frame.origin.y + title.frame.size.height + 5, title.frame.size.width, 0)
content.numberOfLines = 0
content.font = UIFont.systemFontOfSize(13)
content.text = (data["content"] as? String)! + (data["content"] as? String)! + (data["content"] as? String)!
content.sizeToFit()
var height: CGFloat = content.frame.origin.y + content.frame.size.height + 5
return height
}
}
Model.swift
APIからデータを取得する擬似的なクラス
class Model: NSObject
{
func get(callback:(result: [Dictionary<String,AnyObject>]) -> Void)
{
var result: [Dictionary<String, AnyObject>] = []
for var i = 0; i < 50; i++
{
var n = Int(arc4random() % 5 + 1)
var m = Int(arc4random() % 3 + 1)
var content = ""
for var j = 0; j < n; j++ {
content = content + "コメントコメントコメント"
}
var dictionary: Dictionary<String, AnyObject> = [
"icon": "icon" + String(m) + ".jpg",
"name": "ユーザー名",
"content": content,
]
result.insert(dictionary, atIndex: result.count)
}
callback(result: result)
}
}
ずらずらかきましたが以上です
|
__label__pos
| 0.783456 |
Multiple item entry with edit and delete option
Ask about general coding issues or problems here.
Moderators: macek, egami, gesf
rohanraj
New php-forum User
New php-forum User
Posts: 1
Joined: Thu Jul 11, 2013 10:02 am
Multiple item entry with edit and delete option
Postby rohanraj » Thu Jul 11, 2013 10:07 am
Help me with code for sales order in which one can add multiple item and can store it in database. Example.
-------------------------------------------------------------------------------------------
item name | item rate | item quantity| total amount|
LEd 2100 2 4200 |Edit|Delete (line 1)
Mouse 100 4 400 |Edit|Delete (line 2)
Item list | auto fill | manual | Auto fill | Add (line 3)
Grand Total | 4400 |
**Submit**
Item list is taken from databse. item rate should be come auto as specified in database and total amount should come automatically. after pressing add button next line come automatically as line 3 and the added line must look like line 1 and line 2 with edit and delete option. after submitting the form all entry inserted into database.
Help will be highly appreciated.
the work I have done is .....
------------------------------------------------------------------------------------------------------
fee.php
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Fee</title>
<style type="text/css">
<!--
body {
background-image: url(images/background4.jpg);
}
body,td,th {
font-size: 18px;
}
-->
</style>
<style type="text/css">
<!--
h2 {
font-size: 36px;
}
h3 {
font-size: 36px;
}
a:link {
color: #CCC;
}
-->
</style>
<script src="SpryAssets/SpryValidationTextField.js" type="text/javascript"></script>
<link href="SpryAssets/SpryValidationTextField.css" rel="stylesheet" type="text/css" />
</head>
<link href="/Styles/MainStyle.css" rel="stylesheet" type="text/css">
<link href="/Styles/PrintStyle.css" rel=" stylesheet"
type="text/css" media="print">
<style type="text/css" media="print">
.NonPrintable
{
display: none;
} </style>
<body><center>
</center>
<form method="post" action="checkfee.php">
<center>
<table width="954" height="265" border="0">
<tr bgcolor="#00CCCC">
<td width="948" height="261" bgcolor="#CCCCCC"><table width="947" height="90" >
<tr>
<td width="939" height="84"><center><h1> </h1>
</center></td>
</tr>
</table><center>
<table width="941">
<tr>
<td width="81"> </td>
<td width="723"><strong><center>
Fee
</center></strong></td>
<td width="121">Rs.
<?php
$host="localhost";
$username="root";
$password="";
$database="maggot";
mysql_connect($host,$username,$password);
mysql_select_db("$database");
$query = mysql_query("SELECT MAX(rate) FROM `billing_type`
WHERE department='Fee'");
$results = mysql_fetch_array($query);
$cur_auto_id = $results['MAX(rate)'] ;
echo $cur_auto_id;
//echo" <input type='text' name='recieved_in_words' value='$cur_auto_id' />";
?>
only</td>
</tr>
</table>
</center>
<table width="948" height="30" >
<tr>
<td width="223" height="24" align="left">
<label>Bill No :
<?php
$host="localhost";
$username="root";
$password="";
$database="maggot";
mysql_connect($host,$username,$password);
mysql_select_db("$database");
$query = mysql_query("SELECT MAX(bill) FROM `arv`
WHERE department='Fee'");
$results = mysql_fetch_array($query);
$cur_auto_id = $results['MAX(bill)'] + 1;
echo $cur_auto_id;
?>
</label>
</td>
<td width="492"><strong><center>Cash Reciept</center> </strong></td>
<td width="217" align="right">
<label>Date :
<?php
echo date("Y/m/d");
?>
</label>
</td>
</tr>
</table>
<center>
</center>
<table width="950" height="30">
<tr>
<td width="377" height="24" align="left">
<label>Item Name :<span id="sprytextfield1">
<input type="text" name="itemname" id="text1" />
<span class="textfieldRequiredMsg">A value is required.</span></span></label>
</td>
<td width="353" align="left">
<label>rate :<span id="sprytextfield2">
<input type="text" name="rate" id="text2" />
<span class="textfieldRequiredMsg">A value is required.</span><span class="textfieldInvalidFormatMsg">Invalid format.</span></span></label>
</td>
<td width="204" align="right">
<label>quantity :<span id="sprytextfield3">
<input type="text" name="quantity" id="text3" />
<span class="textfieldRequiredMsg">A value is required.</span></span></label>
</td>
</tr>
</table>
<table width="950" height="28" >
<tr>
<td width="251" align="left">
<label>total :<span id="sprytextfield4">
<input type="text" name="total" id="text4" />
<span class="textfieldRequiredMsg">A value is required.</span></span></label>
</td>
<td width="687" align="left">
<label>grand total :<span id="sprytextfield5">
<input type="text" name="grandtotal" id="text5" />
<span class="textfieldRequiredMsg">A value is required.</span></span></label>
</td>
</tr>
</table>
<table width="950" height="30">
<tr>
<td width="259" height="24"><p>Signature of .................................</p></td>
<td width="480"> </td>
<td width="195"><p>Signature of...................</p></td>
</tr>
</table>
<table width="945" border="0">
<tr>
<td width="468"><label>
<center><input type="submit" name="button" id="button" value="Submit" class="NonPrintable"/>
</center></label></td>
<td width="467"><center></center></td>
</tr>
</table></td>
</tr>
</table>
</center></form>
<script type="text/javascript">
<!--
var sprytextfield1 = new Spry.Widget.ValidationTextField("sprytextfield1");
var sprytextfield2 = new Spry.Widget.ValidationTextField("sprytextfield2", "integer");
var sprytextfield3 = new Spry.Widget.ValidationTextField("sprytextfield3");
var sprytextfield4 = new Spry.Widget.ValidationTextField("sprytextfield4");
var sprytextfield5 = new Spry.Widget.ValidationTextField("sprytextfield5");
//-->
</script>
</body>
</html>
----------------------------------------------------------------------------------------------------------------
checkfee.php
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>fee</title>
<style type="text/css">
<!--
body {
background-image: url(images/background4.jpg);
}
body,td,th {
font-size: 18px;
}
-->
</style>
<style type="text/css">
<!--
h2 {
font-size: 36px;
}
h3 {
font-size: 36px;
}
a:link {
color: #CCC;
}
-->
</style></head>
<link href="/Styles/MainStyle.css" rel="stylesheet" type="text/css">
<link href="/Styles/PrintStyle.css" rel=" stylesheet"
type="text/css" media="print">
<style type="text/css" media="print">
.NonPrintable
{
display: none;
} </style>
<body><center>
</center>
<form method="post" action="">
<center>
<table width="954" height="265" border="0">
<tr bgcolor="#00CCCC">
<td width="948" height="261" bgcolor="#CCCCCC"><table width="947" height="90" >
<tr>
<td width="939" height="84"><center><h1> </h1>
</center></td>
</tr>
</table><center>
<table width="941">
<tr>
<td width="81"> </td>
<td width="766"><strong><center>
Fee
</center></strong></td>
<td width="78">Rs. <?php
$host="localhost";
$username="root";
$password="";
$database="maggot";
mysql_connect($host,$username,$password);
mysql_select_db("$database");
$query = mysql_query("SELECT MAX(rate) FROM `billing_type`
WHERE department='Fee'");
$results = mysql_fetch_array($query);
$cur_auto_id = $results['MAX(rate)'] ;
echo $cur_auto_id;
//echo" <input type='text' name='recieved_in_words' value='$cur_auto_id' />";
?> only</td>
</tr>
</table>
</center>
<table width="948" height="30" >
<tr>
<td width="223" height="24" align="left">
<label>Bill No :
<?php
$host="localhost";
$username="root";
$password="";
$database="maggot";
mysql_connect($host,$username,$password);
mysql_select_db("$database");
$department=$_POST['item'];
$query = mysql_query("SELECT MAX(bill_no) FROM `arv` ");
$results = mysql_fetch_array($query);
$cur_auto_id = $results['MAX(bill_no)'] + 1;
echo $cur_auto_id;
?>
</label>
</td>
<td width="492"><strong><center>Cash Reciept</center> </strong></td>
<td width="217" align="right">
<label>Date :
<?php
echo date("Y/m/d");
?>
</label>
</td>
</tr>
</table>
<center>
</center>
<table width="950" height="30">
<tr>
<td width="435" height="24" align="left">
<label>Name :
<?php
print $_POST['itemname'];
?>
</label>
</td>
<td width="295" align="left">
<label>Age :
<?php
print $_POST['rate'];
?>
</label>
</td>
<td width="204" align="right">
<label>Sex :
<?php
print $_POST['quantity'];
?>
</label>
</td>
</tr>
</table>
<table width="950" height="28" >
<tr>
<td width="435" align="left">
<label>Ward :
<?php
print $_POST['total'];
?>
</label>
</td>
<td width="503" align="left">
<label>Bed No. :
<?php
print $_POST['grandtotal'];
?>
</label>
</td>
</tr>
</table>
<table width="950" height="30">
<tr>
<td width="259" height="24"><p>Signature of .................................</p></td>
<td width="480"> </td>
<td width="195"><p>Signature of...................</p></td>
</tr>
</table>
<table width="945" border="0">
<tr>
<td width="468"><label>
<center>
</center></label></td>
<td width="467"><center><input type="submit" name="button2" id="button2" value="Print" onclick="window.print();return false;" class="NonPrintable"/></center></td>
</tr>
</table></td>
</tr>
</table>
</center></form>
</body>
</html>
<?php
require_once ('../connections/connection.php');
$bill_no=$_POST['bill_no'];
$date=date('Y/m/d');
$name=$_POST['itemname'];
$rate=$_POST['rate'];
$total=$_POST['total'];
$grandtotal=$_POST['grandtotal'];
$quantity=$_POST['quantity'];
$sql1="INSERT INTO arv ( user, bill, date, itemname, rate, quantity, total, grandtotal)
VALUES ('$sname', '$bill_no', '$date', '$itemname', '$rate', '$quantity', '$total', '$grandtotal' )";
mysql_query($sql1);
echo "Form Submitted";
?>
johnj
php-forum Super User
php-forum Super User
Posts: 1805
Joined: Thu Mar 10, 2011 5:07 pm
Re: Multiple item entry with edit and delete option
Postby johnj » Sat Jul 13, 2013 5:58 am
What is the problem that you are facing?
Return to “PHP coding => General”
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Question about random variables
1. Feb 9, 2012 #1
I think I understand the concept of random variable (for example, the number of heads when three coins are tossed together or the temperature of a place at 6.00am every morning).
I am, however, confused as I have seen some material which refers even the values taken by a random variable (or instances) as random variables. For example, consider the text from a PowerPoint presentation. The second part, for example, calls the members of a sample as independent variables.
How should I think about this?
Thanks.
Text from a presentation.
“Suppose we are given a random variable X with some unknown probability distribution. We want to estimate the basic parameters of this distribution, like the expectation of X and the variance of X. The usual way to do this is to observe n independent variables all with the same distribution as X”
“Let X1,X2,…,Xn be independent and identically distributed random variables having c. d. f. F and expected value μ. Such a sequence of random variables is said to constitute a sample from the distribution F.”
2. jcsd
3. Feb 9, 2012 #2
mathman
User Avatar
Science Advisor
Gold Member
The language is a little faulty. He seems to be using random variable to mean both the variable and a sample of the variable. For example the outcome of a coin toss is a random variable with two possible outcomes. Once you toss a coin you are taking a sample.
4. Feb 9, 2012 #3
Stephen Tashi
User Avatar
Science Advisor
If you have a random variable X and you consider the process of taking n independent samples of it (as opposed to taking one definite sample with fixed numerical values) then you have a random vector. Random vectors are sometimes called random variables (just as in vector math, a "variable" could represent a vector.)
When you think about statistics, it is a mistake to try to think about a typical problem in terms of a single random variable. Anything that is a function of a random variable is another random variable to worry about. Thus a random sample of n independent realizations of the random variable X is a random vector. The mean of this sample is another random variable. The variance of the sample is another random variable. The unbiased estimator of the sample variance is another random variable. A statistic, such as the t-statistic is a function of the sample values, so it becomes another random variable. (This is particularly confusing if you are used to thinking of "a statistic" as definite numerical value, such as 78.3 years. In statistics, a statistic is any function of the sample values and hence it is a random variable. Adding further to the confusion is the fact that terms like "sample variance" and "sample mean" are sometimes used to refer to specific numerical results instead of functions of random variables. )
5. Feb 10, 2012 #4
Thanks folks.
Ok. Now I get it. But I have a follow up question. The term IID- independent and identically distributed - a commonly used qualifier for most random variables.
If I am taking samples of a random variable, I am picking points from one distribution. Why do I have to use the qualifier 'identically distributed'?
Also, how does a non-identically distributed sample of a random variable look?
6. Feb 10, 2012 #5
lavinia
User Avatar
Science Advisor
When one has a large number of independent samples of a distribution then the average of the sample is a sample from a nearly normally distributed random variable - assuming that the original distribution has finite variance. Further the mean of the nearly normal distribution
is the mean of the original distribution and its variance converges to zero for increasingly large samples. This is the Central Limit Theorem
http://en.wikipedia.org/wiki/Central_limit_theorem#Classical_CLT
Classical statistics is possible because large averages are close to normally distributed even when the original distribution is unknown. All you need is finite variance and mean. So these two parameters can be accurately estimated from the averages of independent samples because normal distributions are well understood.
The crux of this line of reasoning is the idea of independent sampling. Independent samples from a single random variable are equivalent to samples of different random variables with the same distribution. Independence means that nothing is changed by the sampling process. The samples are the same as if they were taken from different random variables.
It is not unfair to say that the thing that differentiates probability theory from analysis is the idea of independence. This in my opinion is what you should try to understand. Then everything else will make sense.
Last edited: Feb 10, 2012
7. Feb 10, 2012 #6
A sequence of random variables, X1, X2, ... is identically distributed if all have the same distribution function. Then they all have the same set of possible values. For example, X1 is the first flip of a coin, X2 is the second flip, etc.... You could have a bunch of random variables all with different distributions. For example, X1 is the flip of a coin, X2 is the roll of a die, etc.... They are different random variables. But if you repeatedly sample the same random variable then your results are necessarily identically distributed. i.e. X1 is one point drawn from the given distribution, X2 is another point drawn from the same distribution, etc. I think it may be semantics. I know about probability but a statistician may use different language. I think mathman said it well above.
8. Feb 13, 2012 #7
Thanks folks.
But I have a follow up question. The term IID- independent and identically distributed - a commonly used qualifier for most random variables.
If I am taking samples of a random variable, I am picking points from one distribution. Why do I have to use the qualifier 'identically distributed'?
Also, how does a non-identically distributed sample of a random variable look?
9. Feb 13, 2012 #8
HallsofIvy
User Avatar
Staff Emeritus
Science Advisor
If you are picking points "from one distribution" then they are "identically distributed".
As for "non-identically distributed", consider this- flip a coin and roll a single die. The set of "outcomes" is
(H, 1), (H, 2), (H, 3), (H, 4), (H, 5), (H, 6), (T, 1), (T, 2), (T, 3), (T, 4), (T, 5), (T, 6).
10. Feb 13, 2012 #9
Because if the distributions are not identical the steps that follow would not be valid.
The face value of a playing card drawn from a pack without replacement is a simple example.
(Crossposted with HallsofIvy, but I think my example is better ;) so I will let it stand)
11. Feb 14, 2012 #10
... but of course that is an example of a dependent (and non-identically distributed) random variable so perhaps HallsofIvy's example is better after all.
12. Feb 14, 2012 #11
I am not sure, but it seems the distribution of these outcomes will be identical. They will have a uniform distribution with 8.3% chance for each outcome. I actually ran a simulation and I was getting an almost uniform distribution. Is that right?
13. Feb 14, 2012 #12
Hey musicgold.
The easiest way to think about a random variable in any context is basically that you have a function that maps a value to a corresponding probability. It's not the most rigorous way of defining it, but for most purposes this is what a random variable is.
You basically associate an event with a probability. In a continuous distribution your event is actually a non-zero simple interval (i.e. [a,b] where a < b) and with discrete portions you associate one particular value with a probability.
If the random variable follows all the Kolmogorov Axioms (all probabilities add up to 1, all are greater than or equal to 0, etc), then you have a random variable.
14. Feb 14, 2012 #13
I think you are confused now musicgold. You are correct about the 1/12 probability but you are now talking about the joint distribution of 2 random variables. When I mentioned this above I was talking about a sequence of random variables.
Flip a coin repeatedly. X1 is the first flip of a coin. X2 is the second, X3 is the third, etc. You generate a sequence {X1,X2,X3,...} of random variables. Since each random variable is drawn from the same distribution, P(H)=P(T)=1/2, then those random variables X1, X2,...are identically distributed. Now generate a sequence {X1,X2,X3,...} where, for example, X1 is the result of flipping a coin, X2 is the result of rolling one die, X3 is the result of spinning the wheel of fortune, X4 is the result of.... You now have a sequence of random variables {X1,X2,X3,...} which are not identically distributed because they are not all drawn from the same distribution.
Don't confuse this with what you did above. The events which all have equal probability 1/12 are the event "one flip of a coin and one roll of a die". So the two actions together are your event, thus the ordered pair to describe one event. Now those events (flip, roll) are identically distributed.
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| 0.952571 |
\begin{equation} \DeclareMathOperator\Gr{Gr} \DeclareMathOperator\LGr{LGr} \DeclareMathOperator\OGr{OGr} \DeclareMathOperator\SGr{SGr} \DeclareMathOperator\Kzero{K_0} \DeclareMathOperator\index{i} \DeclareMathOperator\rk{rk} \end{equation}
Grassmannian.info
A periodic table of (generalised) Grassmannians.
Cayley plane $\mathbb{OP}^2$
There exist other realisations of this Grassmannian:
Betti numbers
\begin{align*} \mathrm{b}_{ 0 } &= 1 \\ \mathrm{b}_{ 2 } &= 1 \\ \mathrm{b}_{ 4 } &= 1 \\ \mathrm{b}_{ 6 } &= 1 \\ \mathrm{b}_{ 8 } &= 2 \\ \mathrm{b}_{ 10 } &= 2 \\ \mathrm{b}_{ 12 } &= 2 \\ \mathrm{b}_{ 14 } &= 2 \\ \mathrm{b}_{ 16 } &= 3 \\ \mathrm{b}_{ 18 } &= 2 \\ \mathrm{b}_{ 20 } &= 2 \\ \mathrm{b}_{ 22 } &= 2 \\ \mathrm{b}_{ 24 } &= 2 \\ \mathrm{b}_{ 26 } &= 1 \\ \mathrm{b}_{ 28 } &= 1 \\ \mathrm{b}_{ 30 } &= 1 \\ \mathrm{b}_{ 32 } &= 1 \end{align*}
Basic information
dimension
16
index
12
Euler characteristic
27
Betti numbers
$\mathrm{b}_{ 0 } = 1$, $\mathrm{b}_{ 2 } = 1$, $\mathrm{b}_{ 4 } = 1$, $\mathrm{b}_{ 6 } = 1$, $\mathrm{b}_{ 8 } = 2$, $\mathrm{b}_{ 10 } = 2$, $\mathrm{b}_{ 12 } = 2$, $\mathrm{b}_{ 14 } = 2$, $\mathrm{b}_{ 16 } = 3$, $\mathrm{b}_{ 18 } = 2$, $\mathrm{b}_{ 20 } = 2$, $\mathrm{b}_{ 22 } = 2$, $\mathrm{b}_{ 24 } = 2$, $\mathrm{b}_{ 26 } = 1$, $\mathrm{b}_{ 28 } = 1$, $\mathrm{b}_{ 30 } = 1$, $\mathrm{b}_{ 32 } = 1$
$\mathrm{Aut}^0(\mathbb{OP}^2)$
adjoint group of type $\mathrm{E}_{ 6 }$
$\pi_0\mathrm{Aut}(\mathbb{OP}^2)$
$1$
$\dim\mathrm{Aut}^0(\mathbb{OP}^2)$
78
Projective geometry
minimal embedding
$\mathbb{OP}^2\hookrightarrow\mathbb{P}^{ 26 }$
degree
78
Hilbert series
1, 27, 351, 3003, 19305, 100386, 442442, 1706562, 5895396, 18559580, 53965548, 146477916, 374332452, 907036326, 2096092350, 4642456390, 9895762305, 20373628275, 40639459575, 78751105875, ...
Exceptional collections
• Faenzi–Manivel constructed a full exceptional sequence in 2013, see MR3293722.
Quantum cohomology
The small quantum cohomology is generically semisimple.
The big quantum cohomology is generically semisimple.
The eigenvalues of quantum multiplication by $\mathrm{c}_1(\mathbb{OP}^2)$ are given by:
Homological projective duality
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How to set the Size of the ListBox in C#?
In Windows Forms, ListBox control is used to show multiple elements in a list, from which a user can select one or more elements and the elements are generally displayed in multiple columns. In ListBox, you are allowed to set the height and width of the ListBox in pixels using Size Property of the ListBox which makes your ListBox more attractive. You can set this property in two different ways:
1. Design-Time: It is the easiest way to set the size of the ListBox as shown in the following steps:
• Step 1: Create a windows form as shown in the below image:
Visual Studio -> File -> New -> Project -> WindowsFormApp
• Step 2: Drag the ListBox control from the ToolBox and drop it on the windows form. You are allowed to place a ListBox control anywhere on the windows form according to your need.
• Step 3: After drag and drop you will go to the properties of the ListBox control to set the size of the ListBox.
Output:
2. RunTime: It is a little bit trickier than the above method. In this method, you can set the size of the ListBox control programmatically with the help of given syntax:
public System.Drawing.Size Size { get; set; }
Here, Size indicates the height and width of the ListBox in pixels. The following steps show how to set the size of the ListBox dynamically:
• Step 1: Create a list box using the ListBox() constructor is provided by the ListBox class.
// Creating ListBox using ListBox class constructor
ListBox mylist = new ListBox();
• Step 2: After creating ListBox, set the Size property of the ListBox provided by the ListBox class.
// Setting the size of the ListBox
mylist.Size = new Size(120, 95);
• Step 3: And last add this ListBox control to the form using Add() method.
// Add this ListBox to the form
this.Controls.Add(mylist);
Example:
filter_none
edit
close
play_arrow
link
brightness_4
code
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace WindowsFormsApp25 {
public partial class Form1 : Form {
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
// Creating and setting
// the properties of ListBox
ListBox mylist = new ListBox();
mylist.Location = new Point(287, 109);
mylist.Size = new Size(120, 95);
mylist.ForeColor = Color.Purple;
mylist.Items.Add(123);
mylist.Items.Add(456);
mylist.Items.Add(789);
// Adding ListBox control to the form
this.Controls.Add(mylist);
}
}
}
chevron_right
Output:
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| 0.962402 |
Helper for most common use of `std::sync::Once`
#1
Probably the most common thing std::sync::Once is used for is to ensure safe lazy initialization of a global, like this:
use std::sync::{Once, ONCE_INIT};
fn expensive_integer() -> i32 {
static mut EXPENSIVE_INTEGER: i32 = 0;
static mut EXPENSIVE_INTEGER_INIT: Once = ONCE_INIT;
EXPENSIVE_INTEGER_INIT.call_once(|| {
unsafe { EXPENSIVE_INTEGER = /* expensive computation */; }
});
unsafe { EXPENSIVE_INTEGER }
}
This is repetitive and requires unsafe blocks. I’d like to suggest a wrapper that can be used like this instead
use std::sync::InitOnce;
static expensive_integer: InitOnce<i32> = InitOnce::new(|| /* expensive computation */);
Under the hood it’s doing the exact same thing, and then implementing Deref so that it looks like a normal immutable value of type T to consumers.
In addition to being shorter and not requiring application code to use unsafe, please note that in my first example, all of the expensive computation is inside an unsafe block, unless the author takes special care to hoist it. In the second example, that naturally doesn’t happen.
What do people think? This seems simple enough that I may just implement it and send a PR unless everyone hates it.
(Yes, this is essentially what lazy_static does with different syntax. You can’t always use third party crates.)
[pre-RFC] lazy-static move to std
#2
Sounds nice. What is the rationale for this design compared to just having lazy_static in stdlib?
#3
Frankly I hadn’t thought at all about that possibility. I’m not the author of lazy_static and I have no idea what they think about merging or not merging it into the stdlib. This design doesn’t involve any macros, but it might turn out to be unusably clunky in some respects if it stays that way (for instance it might be necessary to write static expensive_integer: InitOnce<i32> = InitOnce::<i32>::new(...) which is getting awfully repetitive…)
In summary: :man_shrugging:
#4
Pinging @Kimundi on lazy_static.
Type inference should be able to elide ::<i32> bit at least so you would have:
static expensive_integer: InitOnce<i32> = InitOnce::new(...);
// and for length-visual comparison:
static expensive_integer: InitOnce<i32> = InitOnce::<i32>::new(...)
This gets more important the longer the type becomes of course.
I wonder if this could be further alleviated by allowing you to elide the type entirely on static (and perhaps const):
static expensive_integer = InitOnce::<i32>::new(...)
At that point I think it’s quite ergonomic. But let’s not block on a hypothetical =)
#5
+100 to build-in lazy static without macros.
One thing that bothers me though is that ideally we want to parametrize InitOnceover the function as well, so as to avoid any possibility of indirect call :slight_smile: But I am 100% sure that this’ll be a premature optimization, and storing, as proposed, fn() -> T function pointer will be good enough, and quite probably LLVM will be able to optimize indirect call away anyway.
But looks like to implement InitOnce we’ll need const fn? But that’s probably OK, because calling const fn on stable should be available soon.
Will it be possible to use InitOnce for non-staic lazy variables? Like in struct S { data: InitOnce<i32> }?
Should we use the name Lazy for this type? Should we provide a lazy convenience function, so that the origical example looks like
static expensive_integer: Lazy<i32> = lazy(|| {
// expensive computation
})
#6
FWIW, .NET has a Lazy<T> class that’s very useful: https://docs.microsoft.com/en-us/dotnet/api/system.lazy-1
I love that in Rust we can do better than a LazyThreadSafetyMode parameter to the constructor :heart:
#7
I agree this would be great. In fact we already have something like this in libstd, just a bit specialized: io::lazy::Lazy. Would be nice to be able to reuse other code there :smiley:
EDIT: Actually all that really needs is a reentrant mutex with a const fn initialization function. That’s not easy to do on POSIX though…
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I Forgot My iTunes Backup Password: A Comprehensive Guide to Recovery
Jason
By Jason
Update on
I Forgot My iTunes Backup Password
Have you ever tried to restore your iPhone from an iTunes backup only to be stopped by the dreaded message: “Enter the password for the iPhone backup”? Not being able to access your backup can be incredibly frustrating, especially if you rely on that data for restoring your device.
Don’t panic – there are several methods you can try to recover or reset your iTunes backup password if you’ve forgotten it. This comprehensive guide will walk you through all of your options, from memory tricks to using third party tools, so you can get back into your backup and restore your iPhone or iPad.
Table of Contents show
Overview: Why You Might Need to Recover Your iTunes Backup Password
iTunes gives you the option to encrypt your iPhone and iPad backups with a password. This is recommended for security reasons – it prevents other people from being able to access your backup data.
However, it also means if you forget that password, you’ll be locked out of your own backup. Here are some common situations where you might need to recover or reset your backup password:
• Forgotten password – You set an encryption password previously but have since forgotten it. iTunes asks you for the password when trying to restore, but you have no idea what it is.
• Password never set – iTunes asks for a backup password that you never actually set. This usually happens when restoring from an old backup or transferring backups between computers.
• Incorrect password – You remember your password but keep getting told it’s wrong when you enter it into iTunes. Maybe you remembered it incorrectly or have a keyboard issue entering certain characters.
• Want to change password – You know your current password but want to change it to something new for increased security. However, there is no direct way to change an existing encryption password in iTunes.
• Lost access to encrypted backup – Your backup is encrypted, but something happened to your original computer and iTunes installation. You’ve lost access to the only place that knew the password.
No matter the reason, if you can’t unlock your backup with the correct password, you have two main options:
1. Reset/recover the password so you can access the existing backup normally.
2. Disable encryption to remove password protection entirely and make a new, unencrypted backup.
This guide will explore various methods for both approaches, going in-depth into the pros, cons, and step-by-step instructions for each technique. First, let’s quickly cover the encryption basics.
How iTunes Backup Encryption Works
Before we dive into resetting or recovering your password, it helps to understand how iTunes backup encryption works in the first place:
• Opt-in protection – Encryption is not enabled by default. You have to actively choose to turn it on in iTunes preferences.
• Password required – Once enabled, iTunes will require you to set and enter a password to make new backups or restore from existing encrypted backups.
• Backup files encrypted – The password is used to encrypt your actual backup files on your computer. Only the correct password can decrypt and restore the data.
• Password not stored – Apple does not have access to or store your specific password anywhere (otherwise it would be useless security!). It only knows an encrypted version that can unlock your backups.
• Can’t be changed – There is no official way to change an existing backup encryption password, only disable it fully. You have to reset the password instead.
Knowing these basics will help inform your strategy for solving an unknown or forgotten iTunes backup password. With proper precautions, encryption provides an important layer of security for your iPhone and iPad backups.
Next let’s explore some tactics for jogging your memory or guessing the old password, before we look at more robust password resetting and removal tools.
Method 1: Try to Remember or Guess the Password
If you can’t immediately remember your iTunes backup password, all hope is not lost yet! Here are some tips for jogging your memory or logically guessing the old password:
Look for Password Hints
See if you wrote down any hints or reminders about the password:
• Check your password manager (1Password, LastPass etc) for an iTunes/Apple related login.
• Look in your Notes app or any documents where you may have jotted the password down.
• Check your email inbox for any password reset emails from Apple.
• Look for any sticky notes or records you may have made when originally creating the password.
Retrace Your Steps
Think back to when you first created the password:
• What passwords were you commonly using around that time?
• Were there any special events or dates you may have based it on?
• Was there a pattern or formula you used for creating passwords back then?
Try Familiar Passwords
Attempt using passwords that you commonly use or used to use:
• Your Apple ID or iCloud password
• Passwords for other devices like your Mac or iPad
• Old passwords that you’ve since changed
• Birthdays or anniversaries of loved ones
• The same password you use for multiple accounts
Use Password Rules of Thumb
Try passwords that fit these common formats:
• All lowercase or uppercase letters
• Only the first letter capitalized
• Important dates like 112263 for Nov 22, 1963
• A dictionary word plus sequence like Horse123
• Repeating characters like Aaa111
Going through this introspective process may help ring a bell and recall that long forgotten iTunes backup password! If not, don’t lose hope – keep reading for tools that can help.
Method 2: Use a Password Recovery/Unlocking Tool
If manually guessing just won’t cut it, your next option is to use a dedicated third party tool designed to remove or reset iTunes backup passwords. Let’s compare two of the top options:
Option 1: 4uKey – iPhone Backup Unlocker
Recover the iTunes Backup Password with 4uKey
4uKey from Tenorshare is one of the most popular and trusted tools for getting past a lost iTunes backup password. Here are the key features:
• Works on Windows and Mac computers
• Simple interface and process – no advanced technical skills required
• 3 password recovery/unlocking methods:
• Dictionary attack – Tries wide range of common words and combinations
• Mask attack – Tries password variants based on known partial password
• Brute force attack – Tries all possible combinations (last resort method)
• High success rate for password recovery
• Keeps backup data intact and reusable after removing password
• Also can disable encryption fully before new backup
YouTube video
Overall, 4uKey makes it easy to reset your iTunes backup password, even with minimal information to go off of. It has a high success rate without putting your backup data at risk.
Option 2: iTunes Backup Password Decryptor
Fix i forgot my itunes backup password by itunespassworddecryptor
The iTunes Backup Password Decryptor from SecurityXploded is another option focused solely on iTunes backup passwords. Here are its main capabilities:
• Recovers passwords by extracting them from your local browser data
• Supports all major browsers: Chrome, Firefox, Safari, Internet Explorer, Opera
• Simple wizard-style interface to guide you through process
• Saves recovered passwords in HTML, XML, Text formats
• Completely free tool
This tool takes an indirect but clever approach – instead of unlocking the backups directly, it recovers your forgotten iTunes password by digging it out of your stored browser data. Worth trying before more intensive brute force methods.
Comparing the Options
4uKey is the more robust choice that can reset even fully unknown passwords, while iTunes Password Decryptor relies on you having the password saved in a browser. However, decryptor is a free option that may help in some cases.
We recommend trying the browser-based iTunes Password Decryptor first since it’s low effort, then move to a full-featured unlocker/reset tool like 4uKey if needed.
Both will get the job done without damaging your backups or data, so choose the one that best fits your password situation.
Method 3: Directly Transfer Backup Data to a New Computer
If you just need to access your backup data, another option is to directly transfer the backup files themselves from your iPhone to a new computer.
This avoids the old password while still migrating your data. Let’s look at how it works:
Step 1: Install the Phone Transfer Tool
You’ll need a third party iOS transfer and manager app like dr.fone Phone Manager to pull data directly from your iPhone or iPad.
dr.fone - Phone Manager
Install it on the new computer where you want your backup migrated.
Step 2: Connect iOS Device and Select Transfer
Connect your iPhone or iPad to the new computer and launch dr.fone. Click on the Phone Manager option.
In the next screen, check the box for Transfer iTunes backup files to this computer.
Rebuild iTunes Library using dr.fone
Step 3: Migrate Backup Data to New Computer
Once you click Transfer, dr.fone will automatically pull your iOS backup data from the device to the new computer.
Resolve Forgot My iTunes Backup Password with dr.fone
It does this directly, without needing the old iTunes installation or password.
Pros and Cons
This method avoids your forgotten password issue entirely by transferring your backup to a clean slate.
However, it only retrieves data that currently exists on your device, not old data only in your encrypted backup. So you may lose some historical information.
Evaluate this option if having a working backup – even incomplete – is your top priority. But for full recovery, password reset tools are still preferable.
Method 4: Reset Password by Disabling Encryption
The nuclear option is to remove iTunes backup encryption entirely, erasing your current password and making new unencrypted backups. Here is how it works:
Step 1: Open iTunes and Uncheck Encryption
In your iTunes app on your computer, go to Edit menu > Preferences > Devices tab.
Uncheck the box for “Encrypt iPhone/iPad backup“.
Step 2: Create New Unencrypted Backup
Connect your iPhone or iPad and make a new backup to iTunes. This new backup will not be password protected.
Step 3: Use Unencrypted Backup Going Forward
Now you can restore from this new backup without needing a password. However, your old encrypted backup will remain inaccessible.
When You Should Use This Method
• You’ve exhausted all other options for recovering the password
• Getting a working backup is critical, even if unencrypted
• You have your most important data stored elsewhere like iCloud
• You have no crucial historical data only in the encrypted backup
There are risks to resetting encryption, namely permanent loss of old backup data. Only use this method as a last resort when you’ve fully accepted that tradeoff.
Tips for Avoiding Forgotten Passwords
Resetting or recovering a lost iTunes backup password can be time consuming and risky. Here are some tips to avoid finding yourself in this mess again down the line:
• Write it down – Seriously, keep a written record of the password in a secure physical location. Too easy to forget otherwise.
• Use a password manager – Programs like 1Password and LastPass also make great places to securely store the password.
• Go with your Apple ID password – Using the same password as your main Apple ID can simplify things.
• Create reminders – Set calendar reminders to periodically change the password before you forget it and can no longer access old backups.
• Use strong but memorable passwords – Passphrases or dates meaningful to you are secure yet easier to recall than random strings.
• Disable encryption – If you don’t need the extra security, disabling encryption sidesteps the whole issue.
Key Takeaways and Summary
To wrap up, here are the key tips to remember from this guide on what to do if you forgot your iTunes backup password:
• First manually try guessing the password based on memory tricks, password rules, and personal information.
• Next use password resetting/decryption software like 4uKey and iTunes Decryptor to unlock the backup.
• Directly transfer backup data from your iPhone avoids the old password but risks losing some historical data.
• Turning off encryption lets you make new unencrypted backups but the old one remains inaccessible.
• Avoid future issues by recording passwords securely, using password managers, and disabling encryption when possible.
Resetting a forgotten iTunes backup password is very possible, just follow the techniques in this guide. Don’t let a lost password prevent you from accessing your valuable iPhone or iPad backup ever again!
Frequently Asked Questions
Here are answers to some common questions about resetting and recovering lost iTunes backup passwords:
1. I forgot my iTunes backup password. What are my options?
You have a few options to access your encrypted backup without the password:
• Try to remember the password or guess based on formulas you use
• Use a 3rd party unlock tool to reset the password
• Directly transfer the backup data from your iPhone to a new computer
• Turn off encryption in iTunes to remove passwords
2. How can I view or change my current iTunes backup password?
Unfortunately there is no direct way to view or change an existing backup password in iTunes. You will need to use a 3rd party password reset tool or turn off encryption and make a new backup.
3. Does Apple offer any official solutions for forgotten iTunes passwords?
No, since Apple does not have access to your chosen encryption passwords. You will need to rely on 3rd party software, your own memory, or turning off encryption entirely.
4. What risks are there in resetting my iTunes backup password?
The main risk is potential data loss if you reset the password incorrectly or turn off encryption. This could cause portions of the backup to become inaccessible.
5. Does resetting my password delete any of my backups?
No, resetting the encryption password will not directly cause any data loss or delete any backups. It simply allows you to decrypt and access the backups again.
6. How can I avoid forgetting my iTunes backup password again in the future?
Tips like writing it down securely, using your Apple ID password, and setting calendar reminders to periodically update the password can help avoid future forgotten password issues.
7. Do I need to decrypt iTunes backups if I no longer use that computer?
If you have moved to a new computer and no longer need to access the iTunes backups on your old computer, you do not need to decrypt or unlock the old backups. Simply create new backups on your new computer.
8. What if I forgot my iCloud backup passwords instead of iTunes?
iCloud uses your Apple ID password to manage backups, so you simply need to reset your main Apple ID password to recover access to iCloud backups.
9. Can iPhone unlocking services help with forgotten iTunes passwords?
Unfortunately most unlocking services cannot assist with forgotten iTunes passwords – they can only carrier unlock lost activation locks. You need more specialized iTunes backup unlocking software.
10. If I disable encryption, can I re-enable it later with a new password?
Yes, you can re-enable encryption after disabling to make new encrypted backups. Just be sure you have separate accessible copies of any old backup data before doing so.
Also, let’s fix the iPhone backup failed issues easily now.
Conclusion
Forgotten iTunes backup passwords can stop you dead in your tracks when trying to restore or access your iPhone or iPad data. Thankfully, this guide has outlined several methods to successfully recover and reset your iTunes backup password.
The key is to stay calm, try memory and guessing techniques first, then leverage dedicated tools like 4uKey. You can avoid future issues by recording your password securely and keeping it updated on a regular basis.
With the right approach, you can regain access to your encrypted backups so that lost passwords never have to derail your iPhone restore again!
Jason
Jason
Skilled software testing specialist with expertise in comparisons and research, passionate about blogging, reviews, and creating video tutorials.
THERE’S MORE TO READ.
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| 0.838011 |
Topic: [SOLVED] interoperating w/ Android Trusted Execution Environment (TEE)
Hello,
My embedded device needs to securely exchange data with an Android smartphone app that uses the TEE. TEE apps use NIST P256-R1 curve. So my embedded device running wolfCrypt needs to perform ECHD (elliptic curve diffie helman) and support the ECDSA signature algorithm. For ECDH, can I simply create a keypair using wc_DhGenerateKeyPair() or do I also need to call wc_DhSetKey() and specify P256R1? If so, how is the curve specified? I'm new to WolfCrypt so any help is appreciated!
Share
Re: [SOLVED] interoperating w/ Android Trusted Execution Environment (TEE)
Hi k77,
I believe the API's you are looking for will be defined in <wolfssl-root>/wolfssl/wolfcrypt/ecc.h since it is Elliptic Curve Diffie Helman and not just Diffie Helman (see section #ifdef HAVE_ECC_DHE in ecc.h header file). For creating a new key from scratch wc_ecc_make_key_ex (extended) should be used to address two of your questions as you can pass in specific curve to the extended API.
For the other parts of your question it's not entirely clear if you are trying to load in the key to wolfcrypt or if you are at the point in the algorithm where you have received the public key from the trusted execution environment and wish to generate a shared secret for passing information securely.
To generate a shared secret please use ecc_shared_secret. To load a key into wolfcrypt please the corresponding ecc_import API. (See section #ifdef HAVE_ECC_KEY_IMPORT in ecc.h header for list of API's)
Best Regards,
Kaleb
Re: [SOLVED] interoperating w/ Android Trusted Execution Environment (TEE)
Thanks Kaleb. A follow-up: Can you tell me the difference between curve_id ECC_CURVE_DEF and ECC_SECP256R1?
Share
Re: [SOLVED] interoperating w/ Android Trusted Execution Environment (TEE)
Hi k77,
ECC_SECP256R1 is a valid curve-id
ECC_CURVE_DEF (ECC CURVE DEFAULT) is a flag that tells our library to iterate through the list of SECP or NIST DEFAULT curves.
Warm Regards,
Kaleb
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| 0.958448 |
Ticket #5744: sorted_dict__init_tuples.diff
File sorted_dict__init_tuples.diff, 1.3 KB (added by Thomas Güttler <hv@…>, 8 years ago)
• tests/regressiontests/datastructures/tests.py
5555>>> print repr(d)
5656{'one': 'not one', 'two': 'two', 'three': 'three'}
5757
58Init from sequence of tuples
59>>> d = SortedDict((
60... (1, "one"),
61... (0, "zero"),
62... (2, "two")))
63>>> print repr(d)
64{1: 'one', 0: 'zero', 2: 'two'}
65
5866### DotExpandedDict ############################################################
5967
6068>>> d = DotExpandedDict({'person.1.firstname': ['Simon'], 'person.1.lastname': ['Willison'], 'person.2.firstname': ['Adrian'], 'person.2.lastname': ['Holovaty']})
• django/utils/datastructures.py
5454 def __init__(self, data=None):
5555 if data is None: data = {}
5656 dict.__init__(self, data)
57 self.keyOrder = data.keys()
57 if isinstance(data, dict):
58 self.keyOrder = data.keys()
59 else:
60 self.keyOrder=[key for key, value in data]
5861
5962 def __setitem__(self, key, value):
6063 dict.__setitem__(self, key, value)
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Mebibits (Mib) to Petabytes (PB) calculator
Input the amount of mebibits you want to convert to petabytes in the below input field, and then click in the "Convert" button. But if you want to convert from petabytes to mebibits, please checkout this tool.
Formula
Formula used to convert Mib to PB:
F(x) = x / 7629394531.25
For example, if you want to convert 15 Mib to PB, just replace x by 15 [Mib]:
15 Mib = 15/7629394531.25 = 1.96608e-09 PB
Steps
1. Divide the amount of mebibits by 7629394531.25.
2. The result will be expressed in petabytes.
Mebibit to Petabyte Conversion Table
The following table will show the most common conversions for Mebibits (Mib) to Petabytes (PB):
Mebibits (Mib) Petabytes (PB)
0.001 Mib 0 PB
0.01 Mib 0 PB
0.1 Mib 0 PB
1 Mib 0.0000000001 PB
2 Mib 0.0000000003 PB
3 Mib 0.0000000004 PB
4 Mib 0.0000000005 PB
5 Mib 0.0000000007 PB
6 Mib 0.0000000008 PB
7 Mib 0.0000000009 PB
8 Mib 0.000000001 PB
9 Mib 0.0000000012 PB
10 Mib 0.0000000013 PB
20 Mib 0.0000000026 PB
30 Mib 0.0000000039 PB
40 Mib 0.0000000052 PB
50 Mib 0.0000000066 PB
60 Mib 0.0000000079 PB
70 Mib 0.0000000092 PB
80 Mib 0.0000000105 PB
90 Mib 0.0000000118 PB
100 Mib 0.0000000131 PB
About Mebibits (Mib)
A mebibit is a unit of measurement for digital information and computer storage. The binary prefix mebi (which is expressed with the letters Mi) is defined in the International System of Quantities (ISQ) as a multiplier of 2^20. Therefore, 1 mebibit is equal to 1,024 kibibits and equal to 1,048,576 bits (around 1.048 megabits). The symbol commonly used to represent a mebibit is Mib (sometimes as Mibit).
About Petabytes (PB)
A petabyte is a unit of measurement for digital information and computer storage. The prefix peta (which is expressed with the letter P) is defined in the International System of Units (SI) as a multiplier of 10^15 (1 quadrillion). Therefore, 1 petabyte is equal to 1,000,000,000,000,000 bytes and equal to 1,000 terabytes. The symbol used to represent a petabyte is PB.
See also
FAQs for Mebibit to Petabyte calculator
What is Mebibit to Petabyte calculator?
Mebibit to Petabyte is a free and online calculator that converts Mebibits to Petabytes.
How do I use Mebibit to Petabyte?
You just have to insert the amount of Mebibits you want to convert and press the "Convert" button. The amount of Petabytes will be outputed in the input field below the button.
Which browsers are supported?
All mayor web browsers are supported, including Internet Explorer, Microsoft Edge, Firefox, Chrome, Safari and Opera.
Which devices does Mebibit to Petabyte work on?
Mebibit to Petabyte calculator works in any device that supports any of the browsers mentioned before. It can be a smartphone, desktop computer, notebook, tablet, etc.
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ArrayTH1D Class Reference
#include <ArrayTH1D.h>
List of all members.
Public Member Functions
ArrayTH1D ()
ArrayTH1D (const Char_t *, const Char_t *, Int_t, Double_t, Double_t, Bool_t variable_flag)
ArrayTH1D (TH1D *hist, Bool_t variable_flag)
~ArrayTH1D ()
Int_t GetNBins ()
Int_t GetNEntries ()
void Fill (Double_t xvalue, Double_t weight)
void Add (ArrayTH1D *arrayhist, Double_t weight)
Double_t GetBinContent (Int_t binplus1)
void SetBinContent (Int_t binplus1, Double_t content)
Double_t GetXaxisGetBinCenter (Int_t binplus1)
Double_t GetXaxisGetBinLowEdge (Int_t binnumber)
Double_t GetXaxisGetBinUpEdge (Int_t binnumber)
void Scale (Double_t scale)
void Decay (Double_t alpha, Double_t sin2)
void Reset ()
Char_t * GetHistName ()
ArrayTH1DCloneArrayHist ()
TH1D * ConvertTH1D (const Char_t *histname)
TH1D * ConvertTH1D ()
Private Member Functions
Int_t GetBinNumber (Double_t xvalue)
void SetNEntries (Int_t entries)
Private Attributes
Int_t fNEntries
Int_t fNBins
Double_t fXMin
Double_t fXMax
Bool_t fVariableBinningFlag
Double_t fUnderflowBinCenter1
Double_t * fOverflowBinCenters
const Char_t * fArrayHistName
const Char_t * fArrayHistTitle
Double_t * fXArray
Double_t * fBinEdges
Detailed Description
Definition at line 8 of file ArrayTH1D.h.
Constructor & Destructor Documentation
ArrayTH1D::ArrayTH1D ( )
Definition at line 12 of file ArrayTH1D.cxx.
Referenced by CloneArrayHist().
00013 {
00014 //Initialise to low level values as constructor
00015 fNBins = 1;
00016 fNEntries = 0;
00017 fXMin = 0.0;
00018 fXMax = 1.0;
00019
00020 fXArray = new Double_t[fNBins+2];
00021 for(Int_t i=0;i<fNBins+2;i++) fXArray[i] = 0.0;
00022 }
ArrayTH1D::ArrayTH1D ( const Char_t * arrayhistname,
const Char_t * arrayhisttitle,
Int_t nbins,
Double_t xmin,
Double_t xmax,
Bool_t variable_flag
)
Definition at line 23 of file ArrayTH1D.cxx.
References fArrayHistName, fArrayHistTitle, fBinEdges, fNBins, fNEntries, fOverflowBinCenters, fUnderflowBinCenter1, fVariableBinningFlag, fXArray, fXMax, and fXMin.
00024 {
00025 fNBins = nbins;
00026 fXMin = xmin;
00027 fXMax = xmax;
00028 fNEntries = 0;
00029 fArrayHistName = arrayhistname;
00030 fArrayHistTitle = arrayhisttitle;
00031 fVariableBinningFlag = variable_flag;
00032
00033 if(fNBins <=0){
00034 cout << " *-* Error: Bin number Incorrect, Setting to 1 " << endl;
00035 fNBins = 1;
00036 }
00037
00038 if(fXMin == fXMax){
00039 cout << " *-* Error: Min Value = Max Value, Incrementing Max Value by 1 *-* " << endl;
00040 fXMax += 1.;
00041 }
00042
00043 if(fXMin > fXMax){
00044 cout << " *-* Error: Min Value > Max Value, Swapping Limits *-*" << endl;
00045 Double_t fmintemp = fXMin;
00046 Double_t fmaxtemp = fXMax;
00047
00048 fXMin = fmaxtemp;
00049 fXMax = fmintemp;
00050 }
00051 //Set up arrays
00052 fXArray = new Double_t[fNBins+2]; for(Int_t i=0;i<fNBins+2;i++) fXArray[i] = 0.0;
00053 fBinEdges = new Double_t[fNBins+1]; for(Int_t i=0;i<fNBins+1;i++) fBinEdges[i] = 0.0;
00054 fOverflowBinCenters = new Double_t[21]; for(Int_t i=0;i<21;i++) fOverflowBinCenters[i] = 0.0;//setup here, only use if varialbe binning array
00055
00056 if(!fVariableBinningFlag){
00057 Double_t binwidth = (fXMax - fXMin)/fNBins;
00058 for(Int_t i=0;i<fNBins;i++) fBinEdges[i+1] = fBinEdges[i] + binwidth;
00059 }
00060
00061 if(fVariableBinningFlag){
00062
00063 if( fNBins<100 ){
00064 cout << " ******** ERROR ERROR ERROR " << endl;
00065 }
00066
00067 fUnderflowBinCenter1 = 0.25;
00068 fOverflowBinCenters[0] = 20.5;
00069 for(Int_t i=0;i<9;i++) fOverflowBinCenters[i+1] = fOverflowBinCenters[i] + 1;
00070 fOverflowBinCenters[10] = 31;
00071 for(Int_t i=1;i<10;i++) fOverflowBinCenters[i+10] = fOverflowBinCenters[i+9] + 2;
00072 fOverflowBinCenters[20] = 75;
00073
00074 fBinEdges[1] = 0.5;
00075 for(Int_t i=2;i<80;i++) fBinEdges[i] = fBinEdges[i-1] + 0.25;
00076 for(Int_t i=80;i<90;i++) fBinEdges[i] = fBinEdges[i-1] + 1;
00077 for(Int_t i=90;i<99;i++) fBinEdges[i] = fBinEdges[i-1] + 2;
00078 fBinEdges[99] = 50; fBinEdges[100] = 200;
00079 }
00080 }
ArrayTH1D::ArrayTH1D ( TH1D * hist,
Bool_t variable_flag
)
Definition at line 82 of file ArrayTH1D.cxx.
References fBinEdges, fNBins, fNEntries, fOverflowBinCenters, fUnderflowBinCenter1, fVariableBinningFlag, fXArray, fXMax, and fXMin.
00083 {
00084 fNBins = hist->GetXaxis()->GetNbins();
00085 fXMin = hist->GetXaxis()->GetBinLowEdge(1);
00086 fXMax = hist->GetXaxis()->GetBinUpEdge(fNBins);
00087 fNEntries = (Int_t)hist->GetEntries();
00088 fVariableBinningFlag = variable_flag;
00089
00090 fXArray = new Double_t[fNBins+2]; for(Int_t i=0;i<fNBins+2;i++) fXArray[i] = 0.0;
00091 fBinEdges = new Double_t[fNBins+1]; for(Int_t i=0;i<fNBins+1;i++) fBinEdges[i] = 0.0;
00092 fOverflowBinCenters = new Double_t[21]; for(Int_t i=0;i<21;i++) fOverflowBinCenters[i] = 0.0;//setup here, only use if varalbe binning array
00093
00094 fBinEdges[0] = hist->GetXaxis()->GetBinLowEdge(1);
00095 for(Int_t i=0;i<fNBins+1;i++){
00096 fBinEdges[i] = hist->GetXaxis()->GetBinUpEdge(i+1);
00097 }
00098
00099 for(Int_t i=0;i<fNBins+2;i++){
00100 fXArray[i] = hist->GetBinContent(i); //copies overflow
00101 }
00102
00103 if(fVariableBinningFlag){
00104
00105 fUnderflowBinCenter1 = 0.25;
00106 fOverflowBinCenters[0] = 20.5;
00107 for(Int_t i=0;i<9;i++) fOverflowBinCenters[i+1] = fOverflowBinCenters[i] + 1;
00108 fOverflowBinCenters[10] = 31;
00109 for(Int_t i=1;i<10;i++) fOverflowBinCenters[i+10] = fOverflowBinCenters[i+9] + 2;
00110 fOverflowBinCenters[20] = 75;
00111 }
00112 }
ArrayTH1D::~ArrayTH1D ( )
Definition at line 114 of file ArrayTH1D.cxx.
References fBinEdges, fOverflowBinCenters, and fXArray.
00115 {
00116 delete[] fXArray;
00117 delete[] fBinEdges;
00118 delete[] fOverflowBinCenters;
00119 }
Member Function Documentation
void ArrayTH1D::Add ( ArrayTH1D arrayhist,
Double_t weight
)
Definition at line 160 of file ArrayTH1D.cxx.
References fNBins, fNEntries, fXArray, GetBinContent(), and GetNBins().
Referenced by GhostSample::GetSpectrum(), and GhostSample::InterpMin().
00161 {
00162 if(this->fNBins == arrayhist->GetNBins()){
00163 for(Int_t i=0;i<fNBins+2;i++){
00164 fXArray[i] += weight*(arrayhist->GetBinContent(i));
00165 }
00166 fNEntries += arrayhist->fNEntries;
00167 }
00168 else cout << " *-* Error: Attempting to Add Array Histograms with Different Numbers of Bins *-*" << endl;
00169 }
ArrayTH1D * ArrayTH1D::CloneArrayHist ( )
Definition at line 187 of file ArrayTH1D.cxx.
References ArrayTH1D(), fNBins, fNEntries, fVariableBinningFlag, fXArray, fXMax, fXMin, SetBinContent(), and SetNEntries().
00188 {
00189 ArrayTH1D* ArrayTH1Dtemp;
00190 const Char_t* name = "clone";
00191 ArrayTH1Dtemp = new ArrayTH1D(name,name,fNBins,fXMin,fXMax,fVariableBinningFlag);
00192 ArrayTH1Dtemp->SetNEntries(fNEntries);
00193
00194 for(int i=0;i<fNBins+2;i++){ //Also clones overflow
00195 Double_t tempbincontent = fXArray[i];
00196 ArrayTH1Dtemp->SetBinContent(i,tempbincontent);
00197 }
00198 return ArrayTH1Dtemp;
00199 }
TH1D * ArrayTH1D::ConvertTH1D ( )
Definition at line 213 of file ArrayTH1D.cxx.
References fArrayHistName, fArrayHistTitle, fBinEdges, fNBins, fNEntries, and fXArray.
00214 {
00215
00216 TH1D* htemp = new TH1D(fArrayHistName,fArrayHistTitle,fNBins,fBinEdges); //Make array for variable bins using, then generate hist
00217
00218 for(Int_t i=0; i<fNBins; i++){
00219 htemp->SetBinContent(i+1,fXArray[i+1]);
00220 }
00221 htemp->SetEntries(fNEntries);
00222 return htemp;
00223 }
TH1D * ArrayTH1D::ConvertTH1D ( const Char_t * histname )
Definition at line 201 of file ArrayTH1D.cxx.
References fBinEdges, fNBins, fNEntries, and fXArray.
Referenced by GhostSample::GetSpectrum().
00202 {
00203
00204 TH1D* htemp = new TH1D(histname,histname,fNBins,fBinEdges);
00205
00206 for(Int_t i=0; i<fNBins; i++){ //Lose information about overflow here
00207 htemp->SetBinContent(i+1,fXArray[i+1]);
00208 }
00209 htemp->SetEntries(fNEntries);
00210 return htemp;
00211 }
void ArrayTH1D::Decay ( Double_t alpha,
Double_t sin2
)
Definition at line 143 of file ArrayTH1D.cxx.
References NuOscProbCalc::DecayWeightNC(), MuELoss::e, fBinEdges, fNBins, and fXArray.
Referenced by GhostSample::GetSpectrum().
00144 {
00145 fXArray[0] *= GhostUtilities::DecayWeightNC(TMath::Max(fBinEdges[0],1e-10),alpha,sin2);
00146 for(Int_t i=1;i<fNBins+2;i++){
00147 Double_t energy = (fBinEdges[i]+fBinEdges[i-1])/2;
00148 fXArray[i] *= GhostUtilities::DecayWeightNC(energy,alpha,sin2);
00149 }
00150 }
void ArrayTH1D::Fill ( Double_t xvalue,
Double_t weight
)
Definition at line 131 of file ArrayTH1D.cxx.
References fNEntries, fXArray, and GetBinNumber().
00132 {
00133 Int_t BinNumber = this->GetBinNumber(xvalue);
00134 fXArray[BinNumber] += weight;
00135 fNEntries += 1;
00136 }
Double_t ArrayTH1D::GetBinContent ( Int_t binplus1 )
Definition at line 171 of file ArrayTH1D.cxx.
References fXArray.
Referenced by Add().
00172 {
00173 if(binplus1 <= fNBins+1 && binplus1 >= 0){
00174 return fXArray[binplus1];
00175 }
00176 return -999;
00177 }
Int_t ArrayTH1D::GetBinNumber ( Double_t xvalue ) [private]
Definition at line 225 of file ArrayTH1D.cxx.
References fBinEdges, fNBins, fXMax, and fXMin.
Referenced by Fill().
00226 {
00227 Int_t fBinNumber = -1;
00228
00229 if(xvalue<=fXMin){
00230 fBinNumber = 0;
00231 return fBinNumber;
00232 }
00233 if(xvalue>=fXMax){
00234 fBinNumber = fNBins + 1;
00235 return fBinNumber;
00236 }
00237 for(Int_t i=0;i<fNBins;i++){
00238 if(fBinEdges[i]<=xvalue && xvalue<fBinEdges[i+1]){
00239 fBinNumber = i+1;
00240 return fBinNumber;
00241 }
00242 }
00243 return -1;
00244 }
Char_t * ArrayTH1D::GetHistName ( )
Definition at line 251 of file ArrayTH1D.cxx.
References fArrayHistName.
00252 {
00253 Char_t* ReturnName = (Char_t*)fArrayHistName;
00254 return ReturnName;
00255 }
Int_t ArrayTH1D::GetNBins ( )
Definition at line 121 of file ArrayTH1D.cxx.
References fNBins.
Referenced by Add().
00122 {
00123 return fNBins;
00124 }
Int_t ArrayTH1D::GetNEntries ( )
Definition at line 126 of file ArrayTH1D.cxx.
References fNEntries.
00127 {
00128 return fNEntries;
00129 }
Double_t ArrayTH1D::GetXaxisGetBinCenter ( Int_t binplus1 )
Definition at line 257 of file ArrayTH1D.cxx.
References fNBins, fOverflowBinCenters, fVariableBinningFlag, fXMax, and fXMin.
00258 {
00259 if(!fVariableBinningFlag){
00260 if(binplus1>=1 && binplus1<=fNBins){
00261 return fXMin + (binplus1-0.5)*(fXMax-fXMin)/(fNBins+0.0);
00262 }
00263 }
00264 if(fVariableBinningFlag){
00265
00266 if(binplus1==1) return 0.25;
00267
00268 if(binplus1>=2 && binplus1<80){
00269 return 0.625 + (binplus1-2)*0.25;;
00270 }
00271
00272 if(binplus1>=80){
00273 return fOverflowBinCenters[binplus1-80];
00274 }
00275 }
00276 if(binplus1<=0){
00277 return fXMin;
00278 }
00279 if(binplus1>fNBins){
00280 return fXMax;
00281 }
00282 return -99999.9;
00283 }
Double_t ArrayTH1D::GetXaxisGetBinLowEdge ( Int_t binnumber )
Definition at line 285 of file ArrayTH1D.cxx.
References fBinEdges, fNBins, fXMax, and fXMin.
00286 {
00287 if(binplus1>=1 && binplus1<=fNBins){
00288 return fBinEdges[binplus1-1];
00289 }
00290
00291 if(binplus1<=0){
00292 cout << " *-* Error: Bin plus1 less than or equal to zero *-*" << endl;
00293 return fXMin;
00294 }
00295
00296 if(binplus1>fNBins){
00297 cout << " *-* Error: Bin plus1 greater then number of bins *-*" << endl;
00298 return fXMax;
00299 }
00300 return -99999.9;
00301 }
Double_t ArrayTH1D::GetXaxisGetBinUpEdge ( Int_t binnumber )
Definition at line 303 of file ArrayTH1D.cxx.
References fBinEdges, fNBins, fXMax, and fXMin.
00304 {
00305 if(binplus1>=1 && binplus1<=fNBins){
00306 return fBinEdges[binplus1];
00307 }
00308
00309 if(binplus1<=0){
00310 cout << " *-* Error: Bin plus1 less than or equal to zero *-*" << endl;
00311 return fXMin;
00312 }
00313
00314 if(binplus1>fNBins){
00315 cout << " *-* Error: Bin plus1 greater then number of bins *-* " << endl;
00316 return fXMax;
00317 }
00318 return -99999.9;
00319 }
void ArrayTH1D::Reset ( )
Definition at line 152 of file ArrayTH1D.cxx.
References fNBins, fNEntries, and fXArray.
Referenced by GhostSample::GetSpectrum(), and GhostSample::InterpolateOscillatedSpectra().
00153 {
00154 for(Int_t i=0;i<fNBins+2;i++){
00155 fXArray[i] = 0.0;
00156 }
00157 fNEntries = 0;
00158 }
void ArrayTH1D::Scale ( Double_t scale )
Definition at line 138 of file ArrayTH1D.cxx.
References fNBins, and fXArray.
Referenced by GhostSample::GetSpectrum().
00139 {
00140 for(Int_t i=0;i<fNBins+2;i++) fXArray[i] = scale*fXArray[i];
00141 }
void ArrayTH1D::SetBinContent ( Int_t binplus1,
Double_t content
)
Definition at line 179 of file ArrayTH1D.cxx.
References fXArray.
Referenced by CloneArrayHist(), and GhostSample::InterpolateOscillatedSpectra().
00180 {
00181 if(binplus1 <= fNBins+1 && binplus1 >= 0){
00182 fXArray[binplus1] = content;
00183 }
00184 else cout << " *-* Error: Bin Number Outside Range *-*" << endl;
00185 }
void ArrayTH1D::SetNEntries ( Int_t entries ) [private]
Definition at line 246 of file ArrayTH1D.cxx.
References fNEntries.
Referenced by CloneArrayHist().
00247 {
00248 fNEntries = entries;
00249 }
Member Data Documentation
const Char_t* ArrayTH1D::fArrayHistName [private]
Definition at line 55 of file ArrayTH1D.h.
Referenced by ArrayTH1D(), ConvertTH1D(), and GetHistName().
const Char_t* ArrayTH1D::fArrayHistTitle [private]
Definition at line 56 of file ArrayTH1D.h.
Referenced by ArrayTH1D(), and ConvertTH1D().
Double_t* ArrayTH1D::fBinEdges [private]
Int_t ArrayTH1D::fNBins [private]
Int_t ArrayTH1D::fNEntries [private]
Definition at line 43 of file ArrayTH1D.h.
Referenced by Add(), ArrayTH1D(), CloneArrayHist(), ConvertTH1D(), Fill(), GetNEntries(), Reset(), and SetNEntries().
Double_t* ArrayTH1D::fOverflowBinCenters [private]
Definition at line 53 of file ArrayTH1D.h.
Referenced by ArrayTH1D(), GetXaxisGetBinCenter(), and ~ArrayTH1D().
Double_t ArrayTH1D::fUnderflowBinCenter1 [private]
Definition at line 51 of file ArrayTH1D.h.
Referenced by ArrayTH1D().
Definition at line 49 of file ArrayTH1D.h.
Referenced by ArrayTH1D(), CloneArrayHist(), and GetXaxisGetBinCenter().
Double_t* ArrayTH1D::fXArray [private]
Double_t ArrayTH1D::fXMax [private]
Double_t ArrayTH1D::fXMin [private]
The documentation for this class was generated from the following files:
Generated on 8 May 2018 for loon by doxygen 1.6.1
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Knowledge Base
All About CSRs and RSAs
A Secure Socket Layer (or SSL) Certificate provides encrypted data transfer between a server and a browser.
If you are transmitting sensitive information like credit card numbers or personal information, you need to secure it with SSL encryption. It is possible for every piece of data to be seen by others unless it is secured by an SSL certificate.
The CSR and RSA key are two components involved in the generation of an SSL certificate. These are provided as blocks of encrypted text and can be confused with one another; however, they are quite different and fill very different roles.
What is a CSR?
A Certificate Signing Request, or CSR, is a block of encrypted text which contains information that will be included in the SSL certificate itself. This includes data such as the organization name, domain name, locality and country. It also includes the public keys for the SSL certificate.
The CSR is generated by the server on which the SSL certificate will be installed, and is then used by the SSL certificate provider to create the SSL certificate itself.
If you are renewing your certificate or if your certificate is expired, then you will need to request a new CSR.
What is an RSA Key?
An RSA key is the private encryption key that will be used to protect sensitive information. As the name implies, an encryption key is used to encode and decode information securely.
Currently, we use a 2048-bit RSA key.
The RSA key is generated by the server which the SSL certificate will be installed upon. You will receive the RSA Key when the CSR Request is submitted.
How Do I Get These?
The CSR will be sent by you to your third-party SSL provider and used to create the SSL certificate itself.
The RSA Key is then returned to us (along with the actual certificate itself) when requesting installation of your third-party SSL certificate.
See also Generate SSH Keys and Connect to Your Account via PuTTY (Windows), Secure Sockets Layer (SSL) Overview, Install an SSL Certificate, Transfer Current SSL to New Account
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Skip to main content
DNSSEC and DNS Amplification Attacks
Published: April 23, 2012
Author: Greg Lindsay, Senior Technical Writer - Windows Server, Microsoft Corporation
A DNS amplification attack (aka DNS reflection attack) is a type of distributed denial of service (DDos) attack that takes advantage of the fact that a small DNS query can generate a much larger response. When combined with source address spoofing, an attacker can direct a large volume of network traffic to a target system by initiating relatively small DNS queries.
The amplification factor in this type of attack depends on the type of DNS query and whether or not a DNS server (used as a middleman in the attack) supports sending large UDP packets in a response, which is a feature intended to optimize DNS communications. If a DNS server does not support large (>512 bytes) UDP packets in a response, it can revert to TCP. This reduces the effectiveness of an amplification attack because TCP is much less vulnerable to source address spoofing.
An attacker who is planning a DNS amplification attack can take advantage of the following:
• Open recursion: Name servers on the Internet that have recursion enabled and provide recursive DNS responses to anyone are referred to as “open resolvers.” The number of DNS servers providing open recursion on the Internet have been estimated to be anywhere from several hundred thousand to several million. In a DNS amplification attack, the open resolver functions as the source of amplification, receiving a small DNS query and returning a much larger DNS response. These DNS servers are not normally compromised, but actually functioning as intended.
• Source address spoofing: Source address spoofing alters a packet's return address so that the packet appears to have come from a source other than the sender. In a DNS amplification attack, the source address for the DNS query is spoofed with the target of the attack, similar to a “Smurf” attack. When an open resolver returns a DNS response, this response is incorrectly sent to the spoofed address.
• Botnets: Botnets are groups of online computers that have been compromised by an attacker. Botnets are used in a DNS amplification attack to send DNS queries to open resolvers.
• Malware: Malware can be used to gain access to botnet computers and provide a means to trigger DNS amplification attacks.
• EDNS0: Extension Mechanisms for DNS (EDNS0 as defined in RFC 2671) allow DNS requestors to advertise the size of their UDP packets and facilitate the transfer of packets larger than 512 bytes. Without EDNS0, a 64 byte query can result in (at most) at 512 byte UDP reply corresponding to an amplification factor of 512/64 = 8x.
• DNSSEC: DNSSEC adds security to DNS responses by providing the ability for DNS servers to validate DNS responses. DNSSEC prevents cache-poisoning attacks, but adds cryptographic signatures resulting in larger DNS message sizes. As a consequence, DNSSEC also requires EDNS0 support; therefore a server that supports DNSSEC will also support large UDP packets in a DNS response. Because of these reasons, DNSSEC has been criticized for contributing to DNS amplification attacks.
If the target of an attack is also a DNS server, a DNS amplification attack using queries for a DNSSEC-signed zone has the potential to increase processor usage due to the cryptographic work involved in validating DNSSEC signed resource records. DNS servers can also just ignore these packets. Note: DNS servers running Windows drop these packets and log them in performance and statistics counter under a packet category of unmatched response.
It is important to note that DNSSEC itself does not enable a successful DNS amplification attack. As previously stated, an 8x amplification factor is possible even without EDNS0 or DNSSEC. Successful DNS amplification attacks do not require EDNS0 or DNSSEC.
To demonstrate how an amplification attack works, and how it is affected by DNSSEC, assume that a very large TXT record has been created on a DNS server. Note that if the record is too large, the server will not use UDP even if EDNS0 is enabled. By default, a DNS server running Windows will fall back to TCP for records that are greater than 4000 bytes in size. This can be demonstrated using Network Monitor:
In the following example, two TXT records are created on a DNS server running Windows Server 8 Beta at 10.123.182.167. Each TXT record consists of lines of text that are 256 bytes in length.
• oktxt.contoso.com contains 15 lines: 15 x 256 = 3840 bytes.
• bigtxt.contoso.com contains 16 lines: 16 x 256 = 4096 bytes.
To issue a query for these records and specify that large UDP packets are allowed in the response, we can use dig (dig @10.123.182.167 oktxt.contoso.com any +edns=0) or the resolve-dnsname Windows PowerShell cmdlet available in Windows 8 Beta. The dnssecok flag tells the server that large UDP response packets are supported:
The queries above are issued from a client computer at 10.123.183.140. Network Monitor on the DNS server shows that bigtxt.contoso.com uses TCP whereas oktxt.contoso.com uses UDP:
Specifically, the frame details for these queries show that the largest UDP playload size is 4000 bytes, and in the case of the bigtxt.contoso.com record the size was 4096 bytes (over the limit):
Since the 4000 byte UDP limit was exceeded, the DNS server used TCP in the DNS response.
The 4000 byte limit can also be displayed on the DNS server using Windows PowerShell:
PS C:\> (Get-DnsServer).ServerSetting.MaximumUdpPacketSize
4000
The frame details for oktxt.contoso.com are below. Only UDP was used for this resource record of length 3840 bytes because it is under the 4000 byte limit:
Recall that UDP is important in DNS amplification attacks because source address spoofing is a critical part of the attack. The three-way handshake used by TCP makes spoofing much more difficult than when DNS responses use UDP. Therefore, an attacker will typically want to limit the size of response so that only UDP is used.
An attacker using the oktxt.contoso.com TXT record can theoretically use a minimum transmission unit size of 64 bytes to issue a query that returns a 3840 byte UDP response, giving an amplification factor of 3840/64 = 60x.
DNS Responses in Signed Zones
What happens if the zone is signed? Windows 8 supports zone signing using Windows PowerShell or using a DNSSEC zone signing wizard available in DNS Manager. This process adds several new resource records to the zone, and these records are returned with the query results. Does this increase the amplification factor in a DNS amplification attack?
After zone signing, a query for oktxt.contoso.com (the smaller TXT record) provides the following network conversations:
There is a TCP conversation in addition to the UDP one, similar to what happened previously with the larger TXT record, bigtxt.contoso.com.
Examination of frame details for the UDP exchange reveals that the same TXT record is sent over UDP as was sent before zone signing:
After zone signing, the additional TCP packet exchange includes the DNSSEC related records (RRSIG):
Signing a DNS zone and adding DNSSEC records to a DNS response increases the total size of a response, but does not increase the risk for DNS amplification past the existing limit placed on the server for UDP response size.
Since the TCP conversation cannot be easily spoofed, these additional records do not inherently increase the severity of DNS amplification attacks.
However, an amplification factor of 60 is not trivial, and DNS amplification attacks continue to be a risk on the Internet. Some things that you can do to help prevent DNS amplification attacks include:
• Do not place open DNS resolvers on the Internet. Limiting the clients that can access the resolver greatly decreases the ability of an attacker to use it maliciously. This can be accomplished using firewall rules, router IP access lists, or other methods.
• Prevent IP address spoofing by configuring Unicast Reverse Path Forwarding (URPF) on network routers. A router configured to use URPF (defined in RFC3074) limits an attacker’s ability to spoof packets by comparing the packet’s source address with its internal routing tables to determine if the address is plausible. If not, the packet is discarded.
• Deploy an intrusion prevention system (IPS) device or monitor DNSSEC traffic in some way. Large numbers of outgoing packets with the same target address, especially whose count suddenly spikes, is a good indicator of an active attack. Deploying filters to drop, limit, or delay the incoming suspect packets should lessen the impact of the attack on the local network and attack target. As previously mentioned, Windows DNS servers drop unmatched response packets and log them in performance and statistics counters. It is important to regularly monitor these counters.
References
About the Author
Greg Lindsay photoGreg Lindsay is a senior technical writer for Windows Server. He has written documentation for Network Access Protection (NAP), DNS, DHCP, and other networking technologies.
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Isomorphism of matrix groups
by kakarukeys
Tags: groups, isomorphism, matrix
kakarukeys
kakarukeys is offline
#1
Sep24-05, 10:11 AM
P: 190
Can isomorphism of matrix groups
[tex]\phi: G_1 \rightarrow G_2[/tex]
always be expressed by
[tex]\phi(M) = S M S^{-1}[/tex]?
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MrSeaman
MrSeaman is offline
#2
Sep24-05, 12:10 PM
P: 6
I don't know if I got the question right (had linear algebra a long time ago). Can we assume [tex] \phi(\lambda_1 w_1 + \lambda_2 w_2) = \lambda_1 \phi(w_1) + \lambda_2 \phi(w_2) [/tex] and that there is a basis for [tex] G_1, G_2 [/tex]?
I think it works something like this then:
If [tex] { (a_1, a_2, \dots , a_n) } [/tex] is a basis to [tex] G_1 [/tex], what can you say about [tex] { (\phi(a_1), \dots, \phi(a_n))} [/tex] ? What does this say about the linear combination you get by mapping [tex] g_1 = \sum \limits_{i=1}^n \alpha_n a_n [/tex] to [tex]G_2[/tex] by [tex] \phi [/tex] ? What does this mean for an arbitrary basis of G_2?
MrSeaman
MrSeaman is offline
#3
Sep24-05, 01:00 PM
P: 6
Well, since groups are not vector spaces, I think this was just glibberish. Sorry.
Hurkyl
Hurkyl is offline
#4
Sep24-05, 01:26 PM
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P: 16,101
Isomorphism of matrix groups
You have to make a big assumption for φ(M) = SMS^-1 to even have a chance at working -- is it a valid assumption?
kakarukeys
kakarukeys is offline
#5
Sep25-05, 12:39 AM
P: 190
I mean matrix goups of same dimension
let me rephrase the question:
Can isomorphism of matrix groups of same dimension
[tex]\phi: G_1 \rightarrow G_2[/tex]
always be expressed by
[tex]\phi(M) = S M S^{-1}[/tex]?
S is any invertible matrix
MrSeaman
MrSeaman is offline
#6
Sep26-05, 02:56 AM
P: 6
What does "same dimension" mean here?
Would the group of matrices [tex] (A_i) [/tex] have the same dimension as the group of Matrices [tex] \left ( \begin{array}{*{2}{c}}
A_i & 0 \\
0 & 0
\end{array} \right)[/tex] ?
kakarukeys
kakarukeys is offline
#7
Sep26-05, 09:03 PM
P: 190
if dimension of a matrix group is n, then each element is an n x n matrix.
rwilsker
rwilsker is offline
#8
Jun30-08, 11:18 PM
P: 1
I think what you're remembering is the following: Let K be one of the fields R, C, or H. Then, up to equivalence, the only irreducible real representation of K(n) is the natural representation on Kn. Hence, if you have two irreducible real representations r1 and r2 of K(n), then there exists a matrix S such that r2(M) = Sr1(M)S-1 for all M in K(n).
You can find details of this in Lang's Algebra.
matt grime
matt grime is offline
#9
Jul1-08, 04:40 AM
Sci Advisor
HW Helper
P: 9,398
Resurrecting a 3 year old thread?
As it happens, I don't think you're supposed to assume that G_i is the group of all nxn invertible matrices.
The answer to (my take on) the original question is no, since it is equivalent to the assertion that all (faithful) representations of a group are uniquely characterised by dimension, which is not true, eg S_n has two faithful n-1 dim reps (for n>3): the natural permutation representation breaks up as the direct sum of trivial plus an n-1 dim rep V. V\otimes sign is the second, which is different from V if n>3.
cathalcummins
cathalcummins is offline
#10
Jul24-08, 05:00 PM
P: 46
Right, this thread is the closest to the topic I could find.
My question is more convention choice than anything else.
The finite Cyclic [tex]C_3[/tex] group is defined by:
[tex]{e,c,b(=c^2)}[/tex]
where [tex]e[/tex] is the identity, [tex]c[/tex] is rotation through [tex]\frac{2\pi}{3}[/tex] etc. I'm keeping formalities to a minimum here. Clearly, we are rotating a triangle with directed sides in one plane through three angles, yeah?
Now, my question has to do with representations of this group.
Let me begin with how I am learning about groups.
The definition I'm working from (and taking the example from) is in line with H F Jones' "Groups, Representations and Physics Second Ed".
A representation of a Group [tex]G[/tex] is the pair [tex]{\iota, V}[/tex] where [tex]V[/tex] is the vector space which is also a group and
[tex]\iota : G \mapsto V[/tex]
is a homomorphism. With the usual condition that [tex]\iota[/tex] preserves the group structure.
So, some books understandably skip the generality of [tex]V[/tex] and claim that [tex]V=M_{n \times n}[/tex] the set of invertible nxn matrices. And to represent [tex]C_3[/tex] we will use the finite subspace
[tex]R(\theta)= \begin{bmatrix}\cos \theta & -\sin \theta & {0} \\ \sin \theta & \cos \theta & {0} \\ {0} & {0} & {1}\end{bmatrix} [/tex]
where [tex]\theta=0, \frac{2 \pi}{3},\frac{4\pi}{3}[/tex]
A representation of [tex]C_3[/tex] is the pair [tex]{\iota, M}[/tex] where [tex]M[/tex] is the vector space with three elements
[tex]M=R(0),R(\frac{2 \pi}{3}),R(\frac{4\pi}{3})[/tex]
[tex]\iota : G \mapsto M[/tex]
Now, finally, I can ask my question.
According to the book [tex]R(\frac{2 \pi}{3})[/tex] would be the "representation" of [tex]c[/tex] in [tex]C_3[/tex]. I find this kind of confusing.
So what would ([tex]\textbf{x'},\textbf{x}[/tex] are just Cartesian column vectors)
[tex]\textbf{x'}=R(\theta)\textbf{x}[/tex]
be?
Can someone shed some light on how to view this definition as intuitive. I understand that a representation shouldn't demand a co-od system. I suppose, to me, it just seems like we're identifying an 'operator' ([tex]R(\theta)\in M_{n \times n}[/tex]) with a 'state' ([tex]e,c,b \in C_3[/tex]).
n_bourbaki
n_bourbaki is offline
#11
Jul24-08, 05:20 PM
P: 103
Quote Quote by cathalcummins View Post
Right, this thread is the closest to the topic I could find.
My question is more convention choice than anything else.
The finite Cyclic [tex]C_3[/tex] group is defined by:
[tex]{e,c,b(=c^2)}[/tex]
where [tex]e[/tex] is the identity, [tex]c[/tex] is rotation through [tex]\frac{2\pi}{3}[/tex] etc. I'm keeping formalities to a minimum here.
That isn't really a minimum. A cyclic group with 3 elements is just <g: g^3=e>
Clearly, we are rotating a triangle with directed sides in one plane through three angles, yeah?
That is an example of a cyclic group with 3 elements. It is not *the* example.
Now, my question has to do with representations of this group.
There are 3 simple ones over the complex numbers....
Let me begin with how I am learning about groups.
If you're just learning about groups, then it may be best to ignore representations to begin with.
The definition I'm working from (and taking the example from) is in line with H F Jones' "Groups, Representations and Physics Second Ed".
A representation of a Group [tex]G[/tex] is the pair [tex]{\iota, V}[/tex] where [tex]V[/tex] is the vector space which is also a group and
[tex]\iota : G \mapsto V[/tex]
is a homomorphism. With the usual condition that [tex]\iota[/tex] preserves the group structure.
That is not a representation.
So, some books understandably skip the generality of [tex]V[/tex] and claim that [tex]V=M_{n \times n}[/tex] the set of invertible nxn matrices.
See, here's a problem. A vector space V comes equipped with a group operation, sure. Addition. But representations map from G to a set of invertible matrices with the group operation matrix composition.
And to represent [tex]C_3[/tex] we will use the finite subspace
[tex]R(\theta)= \begin{bmatrix}\cos \theta & -\sin \theta & {0} \\ \sin \theta & \cos \theta & {0} \\ {0} & {0} & {1}\end{bmatrix} [/tex]
Representing G, and working out *a* representation are probably not the same thing. Be careful.
where [tex]\theta=0, \frac{2 \pi}{3},\frac{4\pi}{3}[/tex]
A representation of [tex]C_3[/tex] is the pair [tex]{\iota, M}[/tex] where [tex]M[/tex] is the vector space with three elements
[tex]M=R(0),R(\frac{2 \pi}{3}),R(\frac{4\pi}{3})[/tex]
M is not a vector space.
[tex]\iota : G \mapsto M[/tex]
Now, finally, I can ask my question.
According to the book [tex]R(\frac{2 \pi}{3})[/tex] would be the "representation" of [tex]c[/tex] in [tex]C_3[/tex]. I find this kind of confusing.
So what would ([tex]\textbf{x'},\textbf{x}[/tex] are just Cartesian column vectors)
[tex]\textbf{x'}=R(\theta)\textbf{x}[/tex]
be?
Can someone shed some light on how to view this definition as intuitive. I understand that a representation shouldn't demand a co-od system. I suppose, to me, it just seems like we're identifying an 'operator' ([tex]R(\theta)\in M_{n \times n}[/tex]) with a 'state' ([tex]e,c,b \in C_3[/tex]).
You should think of it as identifying a group G with a group of operators, though really we aren't identifying since representations are not isomorphisms from G to something but homomorphisms from G to matrices.
Shall we start again? Let G be a group. A representation of the GROUP G is a group homomorphism from G to the invertible matrices M_n for some n. There are infinitely many such representations.
If G were C_3 as above then one representation of G would send a generator of G to rotation by 2pi/3 in R^2. Another represenatation would be to send a generator of G to the identity matrix in M_n for any n.
cathalcummins
cathalcummins is offline
#12
Jul24-08, 05:27 PM
P: 46
when you say
"send a generator of G to rotation by 2pi/3"
what does "to rotation" mean, like an operator on R^2?
n_bourbaki
n_bourbaki is offline
#13
Jul24-08, 05:33 PM
P: 103
If f is a function from X to Y, and f(x)=y for some x in X, then it is a common abuse of language to say f sends x to y.
A representation is a group homomorphism. A function from G to End(V).
If G=C_3 = <g : g^3=e> , then V=R^2, and the function f(g)=R(2pi/3) - the 2x2 rotation matrix by the angle 2pi/3 - extended in the obvious manner (i.e. f(g^2) is rotation by 4pi/3 etc) is a representation of G.
cathalcummins
cathalcummins is offline
#14
Jul24-08, 05:55 PM
P: 46
May I redefine in more familiar language(to my course).
A representation of C_3 is the pair {i,R^2}, where
i : C_3 -> R^2
is the function taking the following form:
i(g) = R(2pi/3)
where, g \in C_3 and R is the 2X2 rotation matrix.
n_bourbaki
n_bourbaki is offline
#15
Jul24-08, 06:01 PM
P: 103
Quote Quote by cathalcummins View Post
May I redefine in more familiar language(to my course).
A representation of C_3 is the pair {i,R^2}, where
i : C_3 -> R^2
No! That is not a representation. That is just a group hom (presumably) into the vector space R^2.
is the function taking the following form:
i(g) = R(2pi/3)
where, g \in C_3 and R is the 2X2 rotation matrix.
That rotation matrix isn't in R^2, so that makes no sense. As you wrote it, i ought to be a map from C_3 to End(R^2) - the matrices of the linear maps from R^2 to itself- and that is a representation.
I'll say it again: a representation of G is a group hom to the linear maps of a vector space. It is not a map to the vector space itself.
There are several ways of referring to a representation which may be confusing you.
To define a representation of G we need _in full_ a vector space V, and a group homomorphism f:g--> End(V). We may call either f, or V the representation, but the function f is matrix valued.
cathalcummins
cathalcummins is offline
#16
Jul25-08, 03:31 AM
P: 46
I apologise, it was very late last night. It all makes sense now. Further, you have solved the puzzle as to why I thought I was dealing with 'operators'.
I hope that I have it right:
A representation of [tex]C_3[/tex] is the pair [tex]\left\{ \iota,\mathbb{R}^2\right\}[/tex] such that;
[tex]\iota : g \mapsto End(\mathbb{R}^2)[/tex]
[tex]\forall g \in C_3[/tex]. The set of all linear maps over [tex]\mathbb{R}^2[/tex].
Specifically,
[tex]\iota(g)=R(2\pi/3) [/tex]
[tex]\iota(g^2)=R(4\pi/3) [/tex]
[tex]\iota(g^3)=\iota(e)=R(0) [/tex]
Where
[tex]R(\theta)= \begin{bmatrix}\cos \theta & -\sin \theta \\ \sin \theta & \cos \theta\end{bmatrix}[/tex]
is just the rotation matrix. The necessary condition of preservation of group structure are inherited from matrix algebra.
And of course,
[tex]R(\theta) : \mathbb{R}^2 \mapsto \mathbb{R}^2[/tex]
which is what gives us our representation.
cathalcummins
cathalcummins is offline
#17
Jul25-08, 03:43 AM
P: 46
Looking at the definition, I didn't realise that V in his definition was not "the space to visualise things in" [tex]\mathbb{C}^{n \times n}[/tex] but the space of all linear maps over that space. And usually it's just taken to be [tex]M_{n \times n}(\mathbb{C})[/tex]
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-4*(4*cos(1+4*exp(x))*exp(x)+sin(1+4*exp(x)))*exp(x) если x=-1/3 (упростите выражение)
Выражение, которое надо упростить:
Например, 1/(a*x-1)-1/(a*x+1)
Решение
Вы ввели
[LaTeX]
/ / x\ x / x\\ x
-4*\4*cos\1 + 4*e /*e + sin\1 + 4*e //*e
$$- 4 \left(e^{x} 4 \cos{\left (4 e^{x} + 1 \right )} + \sin{\left (4 e^{x} + 1 \right )}\right) e^{x}$$
Подстановка условия
[LaTeX]
(-4*((4*cos(1 + 4*exp(x)))*exp(x) + sin(1 + 4*exp(x))))*exp(x) при x = -1/3
(-4*((4*cos(1 + 4*exp(x)))*exp(x) + sin(1 + 4*exp(x))))*exp(x)
$$- 4 \left(e^{x} 4 \cos{\left (4 e^{x} + 1 \right )} + \sin{\left (4 e^{x} + 1 \right )}\right) e^{x}$$
(-4*((4*cos(1 + 4*exp((-1/3))))*exp((-1/3)) + sin(1 + 4*exp((-1/3)))))*exp((-1/3))
$$- 4 \left(e^{(-1/3)} 4 \cos{\left (4 e^{(-1/3)} + 1 \right )} + \sin{\left (4 e^{(-1/3)} + 1 \right )}\right) e^{(-1/3)}$$
(-4*((4*cos(1 + 4*exp(-1/3)))*exp(-1/3) + sin(1 + 4*exp(-1/3))))*exp(-1/3)
$$\frac{1}{e^{\frac{1}{3}}} \left(-1 \cdot 4 \left(\frac{4}{e^{\frac{1}{3}}} \cos{\left (1 + \frac{4}{e^{\frac{1}{3}}} \right )} + \sin{\left (1 + \frac{4}{e^{\frac{1}{3}}} \right )}\right)\right)$$
(-4*sin(1 + 4*exp(-1/3)) - 16*cos(1 + 4*exp(-1/3))*exp(-1/3))*exp(-1/3)
$$\frac{1}{e^{\frac{1}{3}}} \left(- 4 \sin{\left (1 + \frac{4}{e^{\frac{1}{3}}} \right )} - \frac{16}{e^{\frac{1}{3}}} \cos{\left (1 + \frac{4}{e^{\frac{1}{3}}} \right )}\right)$$
Степени
[LaTeX]
/ / x\ / x\ x\ x
\- 4*sin\1 + 4*e / - 16*cos\1 + 4*e /*e /*e
$$\left(- 16 e^{x} \cos{\left (4 e^{x} + 1 \right )} - 4 \sin{\left (4 e^{x} + 1 \right )}\right) e^{x}$$
Численный ответ
[LaTeX]
-4.0*(4.0*cos(1 + 4*exp(x))*exp(x) + sin(1 + 4*exp(x)))*exp(x)
Рациональный знаменатель
[LaTeX]
/ / x\ / x\ x\ x
\- 4*sin\1 + 4*e / - 16*cos\1 + 4*e /*e /*e
$$\left(- 16 e^{x} \cos{\left (4 e^{x} + 1 \right )} - 4 \sin{\left (4 e^{x} + 1 \right )}\right) e^{x}$$
Объединение рациональных выражений
[LaTeX]
/ / x\ / x\ x\ x
\- 4*sin\1 + 4*e / - 16*cos\1 + 4*e /*e /*e
$$\left(- 16 e^{x} \cos{\left (4 e^{x} + 1 \right )} - 4 \sin{\left (4 e^{x} + 1 \right )}\right) e^{x}$$
Общее упрощение
[LaTeX]
/ / x\ x / x\\ x
-4*\4*cos\1 + 4*e /*e + sin\1 + 4*e //*e
$$- 4 \left(4 e^{x} \cos{\left (4 e^{x} + 1 \right )} + \sin{\left (4 e^{x} + 1 \right )}\right) e^{x}$$
Собрать выражение
[LaTeX]
/ x\ 2*x x / x\
- 16*cos\1 + 4*e /*e - 4*e *sin\1 + 4*e /
$$- 16 e^{2 x} \cos{\left (4 e^{x} + 1 \right )} - 4 e^{x} \sin{\left (4 e^{x} + 1 \right )}$$
/ / x\ / x\ x\ x
\- 4*sin\1 + 4*e / - 4*4*cos\1 + 4*e /*e /*e
$$\left(- 16 e^{x} \cos{\left (4 e^{x} + 1 \right )} - 4 \sin{\left (4 e^{x} + 1 \right )}\right) e^{x}$$
Общий знаменатель
[LaTeX]
/ x\ 2*x x / x\
- 16*cos\1 + 4*e /*e - 4*e *sin\1 + 4*e /
$$- 16 e^{2 x} \cos{\left (4 e^{x} + 1 \right )} - 4 e^{x} \sin{\left (4 e^{x} + 1 \right )}$$
Тригонометрическая часть
[LaTeX]
/ / x\ x / x\\ x
-4*\4*cos\1 + 4*e /*e + sin\1 + 4*e //*e
$$- 4 \left(4 e^{x} \cos{\left (4 e^{x} + 1 \right )} + \sin{\left (4 e^{x} + 1 \right )}\right) e^{x}$$
Комбинаторика
[LaTeX]
/ / x\ x / x\\ x
-4*\4*cos\1 + 4*e /*e + sin\1 + 4*e //*e
$$- 4 \left(4 e^{x} \cos{\left (4 e^{x} + 1 \right )} + \sin{\left (4 e^{x} + 1 \right )}\right) e^{x}$$
Раскрыть выражение
[LaTeX]
/ / x\ / x\ / / x\ / x\\ x\ x
-4*\cos(1)*sin\4*e / + cos\4*e /*sin(1) + 4*\cos(1)*cos\4*e / - sin(1)*sin\4*e //*e /*e
$$- 4 \left(4 \left(- \sin{\left (1 \right )} \sin{\left (4 e^{x} \right )} + \cos{\left (1 \right )} \cos{\left (4 e^{x} \right )}\right) e^{x} + \sin{\left (4 e^{x} \right )} \cos{\left (1 \right )} + \sin{\left (1 \right )} \cos{\left (4 e^{x} \right )}\right) e^{x}$$
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Booking Transactions via our API (for Agents)
NOTE: this guide is only relevant for Agents using the API - for information about booking transactions as a Provider see Booking Transactions via our API (for Providers).
Introduction
For a truly white-label payments experience, your application can implement the Cohort Go payments API to collect all information from the customer and book a transaction from within your own application. Note that this is considered an advanced payment method as it requires significant implementation build and likely maintenance within your application. We highly recommend the Payment Buttons approach as a first approach for integration.
Process Flow
StudentYour WebsiteCohort GoInternational BankCreates an orderCreates an invoice describing the orderProvides an order identifierRequests payment methods for the invoiceAs part of your initial data collection,you'll need to collect a countrythey'll make payment from.Offers available payment methodsSelects Payment MethodRequests identity informationAs part of the payment method data,required identity details will beindicated by Cohort GoProvides Identity InformationBooks TransactionProvides transaction reference(Webhook) Provides link to payment instructionsEmails payment instructionsNotifies that funds are awaitingSends payment to Cohort GoStudentYour WebsiteCohort GoInternational Bank
Before You Begin
1. Ensure you have set up API Authentication.
2. Contact your Cohort Go account representative to ensure your account has been given access to the 'White Label API' feature.
Creating an Invoice
After you've identified what you're looking to bill the customer for, this information should be created as an invoice in the Cohort Go platform. An invoice should be added via the Agent Invoices Endpoint, omitting the details of the student.
An example of this may look like:
curl \
-u '<[email protected]>:<service-token>' \
-d '{
"invoice":{
"institution_name": "University of Melbourne",
"currency": "AUD",
"country":"AU",
"amount": 5500.99,
"document_upload_url":"http://some.host/invoice.pdf",
"retained_commission":55.00
}' \
-H "Content-Type: application/json" \
-XPOST \
https://demo.s.portal.cohortgo.com/api/v1/services/payments/agent_invoices.json
NOTE: If you like to use the 'retained_commission' field to set the commission amount to be retained - please contact your Cohort Go account representative to ensure your account is set up to do so.
This will respond with a payload like:
{
"institution_name": "University of Melbourne",
"currency": "AUD",
"amount": 5500.99,
"payment_reference": "invoice:1234",
"id": "S123456789"
}
Retrieving Payment Methods
After uploading your invoice, you'll need to query for available payment methods for the student's home country. This is achieved via the Payment Methods Endpoint. Along with the payment method data that is returned, the response will include details of the KYC information that you'll need to collect for the customer. To make this call, you'll need to have identified the student's home country (with ISO Alpha-2 country code) and the id of the previous invoice created. This information is used to determine both the amount payable and the currency paths that the payment will make.
Note that the payment methods include presentational information that will need to be displayed in your UI. Specifically, it will describe a short-form title, description and visual logos that should be included.
Assuming that you had previously uploaded an invoice with an id of 1234, then retrieving payment methods would look like:
curl \
-u '<[email protected]>:<service-token>' \
-H "Content-Type: application/json" \
https://demo.s.portal.cohortgo.com/api/v1/services/payments/payment_methods?origin_country=CO&invoices[]=1234
Note: addon_commission_rate - Optional parameter available in some markets. The commission rate being added to the payment amount, represented as basis points. Basis points are calculated by multiplying the percentage by 100, eg. 1% => 100 basis points, 2.5% => 250 etc. Please speak with your Cohort Go Account Manager to understand if this field can be enabled in your market.
This will respond with a payload like (abbreviated for clarity):
{
"expires": "string",
"methods": [
{
...
"identity_field_requirements": [
{
"field": "given_name",
"label": "string",
"required_for_student": "always",
"required_for_payer": "always",
"student_description": "string",
"payer_description": "string"
}
],
...
"documentation_requirements": [
{
"field": "passport",
"required_for_student": "always",
"required_for_payer": "always",
"student_description": "string",
"payer_description": "string"
}
]
}
]
}
Collecting KYC Information
The Payment Methods Endpoint response will include the identity_field_requirements and documentation_requirements properties for each payment method. These are different per payment method and based upon required KYC information. You will need to render the specified fields in your UI using the labels provided by the Cohort Go system (as the appropriate labelling of these are country and payment method dependent).
Note that a Cohort Go transaction requires both a student and payer to be specified. Only if the payer is the same as the student then the payer information can be ommitted.
Structuring Addresses
Given the variation in address formatting globally, Cohort Go accepts different fields depending upon the student/payer's address country.
To retrieve the structuring and labelling for an address, using the Address Config Endpoint. This takes an ISO Alpha-2 country code, and returns the fields that are required from the standard Address set, along with the country sensitive labels to use.
Note that the address country passed for a student or payer does not need to be the same as the home country.
An example of retrieving an address config for India would be:
curl \
-u '<[email protected]>:<service-token>' \
-H "Content-Type: application/json" \
https://demo.s.portal.cohortgo.com/api/v1/addresses/IN
This would return a payload like:
"street_address": {
"label": "Street Address",
"visible": true,
"collection": null,
"required": true,
"hint": false
},
"locality": {
"label": "City/District",
"visible": true,
"collection": null,
"required": true,
"hint": false
},
"sub_locality": {
"label": "Locality/Village Name",
"visible": true,
"collection": null,
"required": true,
"hint": false
},
"sub_region": {
"label": "Sub region",
"visible": false,
"collection": null,
"required": false,
"hint": false
},
"postcode": {
"label": "PIN",
"visible": true,
"collection": null,
"required": true,
"hint": false
},
"region": {
"label": "State",
"visible": true,
"collection": [
[
"Andaman and Nicobar Islands",
"AN"
],
...
],
"required": true,
"hint": null
}
}
Note that not all fields are visible, some should utilise collections (dropdowns) for display, and the labels use local terminology.
Booking a Transaction
After you've completed the collection of KYC, the transaction is ready to be booked via the Book Transaction Endpoint.
Note: to disable email notifications to student ensure the suppress_emails field is set to true.
An example of booking this transaction would look like:
curl \
-u '<[email protected]>:<service-token>' \
-d '{
{
"invoices": ["1234"],
"payment_method": "method:1234",
"rate_sig": "asdasd123asdasd",
"student": {
"email": "[email protected]",
"home_country": "CO",
"given_name": "Stu",
"family_name": "Dent",
"dob": "2000-02-17",
"passport_number": "M123123",
"passport_country": "CO",
"phone_number": "01123123213",
"national_identity_number": "123412",
"passport_url": "http://example.com/passport.pdf",
"supporting_documents": [],
"suppress_emails": true,
"address": {
"street_address": "12 Smith St",
"locality": "Medellin",
"region": "ME",
"postcode": "12345",
"country": "CO"
}
},
"payer": {
"email": "[email protected]",
"given_name": "Payer",
"family_name": "Dent",
"dob": "1970-02-17",
"phone_number": "1235123123",
"passport_country": "CO",
"supporting_documents": [],
"address": {
"street_address": "12 Smith St",
"locality": "Medellin",
"region": "ME",
"postcode": "12345",
"country": "CO"
}
},
"addon_commission_rate": 100
}' \
-H "Content-Type: application/json" \
-XPOST \
https://demo.s.portal.cohortgo.com/api/v1/services/payments/transactions.json
The response to this will include the payment reference (generally in the form CPSxxxx), and may include a payment instructions document, depending upon the output of the automated Cohort Go KYC procedures.
Note: addon_commission_rate - Optional parameter available in some markets. The commission rate being added to the payment amount, represented as basis points. Basis points are calculated by multiplying the percentage by 100, eg. 1% => 100 basis points, 2.5% => 250 etc. Please speak with your Cohort Go Account Manager to understand if this field can be enabled in your market.
If the payment method supports immediate payment (for example, Alipay or Unionpay in China), then the response payload will include an immediate_payment field that provides details for presenting a link to the student to complete their payment.
Links for making immediate payment will need to redirect to the provided url via GET or POST using a hidden form. If the params field is included as part of immediate_payment you will also need to include these paramaters as hidden form fields.
When a transfer form is required to complete payment a transfer_form field will be included in the transaction booking response. This is most common for payments in India that require completing an A2 Form. You will need to provide the student with a link to download the form using the download_url and a way to upload the form to the upload_url once it has been completed. The field will also include a label and description to display in your UI.
An example of a transaction booking response with immediate payment might look like:
{
"reference": "CPS12345",
"payment_instructions_url": "https://example.com/payment_instructions.pdf",
"transfer_form": {
"label": "A2 Form",
"description": "Transfer form required when making payments in India",
"download_url": "https://example.com/a2_form.pdf",
"upload_url": "https://example.com/upload_transfer_form"
},
"immediate_payment": {
"url": "https://merchant.com/payment/request",
"method": "POST",
"params" {
"proc_code": "1234",
"process_code": "1234567",
"trans_date": "20200601",
"merchant_no": "1234567"
}
}
}
Retrieving Transaction Details
After a transaction has been booked, the details of a transaction can be queried by using the Get Transaction endpoint. The payment's due date will also be returned in the response. Assuming that you had previously booked a transaction with a resulting reference of CPS12345, then retrieving the transaction status would look like:
curl \
-u '<[email protected]>:<service-token>' \
-H "Content-Type: application/json" \
https://demo.s.portal.cohortgo.com/api/v1/services/payments/transactions/CPS12345
This will respond with something similar to:
{
"reference": "CPS12345",
"status": "awaiting_funds",
"due_date": "2022-01-20",
"payment_instructions_url": "https://example.com/payment_instructions.pdf",
"payment_proof_upload_url": "https://example.com/payment_proof_upload_url"
}
NOTE: If the transaction is not in the state awaiting_funds, then the additional URL attributes will not appear in the response.
Receiving Transaction Updates
The Cohort Go platform can notify your system of transaction updates if you want to keep track the progress. This can be set up by adding two new fields: notification_url and external_reference when creating an invoice via the Agent Invoices Endpoint. The updates will be delivered by a JSON POST request to the provided URL.
• notification_url - Endpoint where you want to receive the update
• external_reference - Invoice reference number from agent's side
An example of this may look like:
curl \
-u '<[email protected]>:<service-token>' \
-d '{
"invoice":{
"institution_name": "University of Melbourne",
"currency": "AUD",
"country":"AU",
"amount": 5500.99,
"document_upload_url":"http://some.host/invoice.pdf",
"notification_url": "http://notify.test",
"external_reference": "AUS123"
}' \
-H "Content-Type: application/json" \
-XPOST \
https://demo.s.portal.cohortgo.com/api/v1/services/payments/agent_invoices.json
This will respond with a playload like:
{
"institution_name": "University of Melbourne",
"currency": "AUD",
"amount": 5500.99,
"notification_url": "http://notify.test",
"external_reference": "AUS123",
"payment_reference": "invoice:1234",
"id": "S123456789"
}
Transaction updates will be sent if the status has changed to:
1. funds_received - Funds have been received from the student in a foreign currency
2. settled - Funds have been paid to the institution or the education service provider as per invoice
3. expired - Funds have not been received before expiry date
4. cancelled - Transaction request has been cancelled
Funds Received Notification
For a funds received notification, a payload would look like:
{
"reference": "AUS123",
"state": "funds_received",
"transaction": "CPS1234",
"amount": 5500.99,
"cleared_funds": true
}
Points of note in this notification:
• The cleared_funds field will be false in cases where Cohort Go still needs to complete a process of clearing funds with local regulators. It may be possible in these cases that additional information might be needed from the customer to finalise the payment, or further that the payment may need to be cancelled. It is recommended that if you are performing immediate processes based upon a funds_received notification that these processes wait until a "cleared_funds": true value is received. If an initial notification is sent with "cleared_funds": false, then an updated notification will be sent with "cleared_funds": true once this process completes. In some circumstances such as delivery failures, it may be possible that a settled notification will be sent first - in this case, it can be safely assumed that funds did clear.
Settled Notification
For a completion notification, a payload would look like:
{
"reference": "AUS123",
"state": "settled",
"transaction": "CPS1234",
"amount": 5500.99,
"cleared_funds": true
}
Expried Notification
For a expried notification, a payload would look like:
{
"reference": "AUS123",
"state": "expired",
"transaction": "CPS1234",
"amount": 5500.99,
}
Cancelled Notification
For a expried notification, a payload would look like:
{
"reference": "AUS123",
"state": "cancelled",
"transaction": "CPS1234",
"amount": 5500.99,
}
For the fields in each of these notifications:
• reference - reference number from agent's side for the payment being made;
• state - the state of the invoice - will be one of awaiting_funds, funds_received or settled;
• transaction - the Cohort Go internal reference for the payment being made. This can be treated as a unique reference for a given payment;
• amount - the amount paid;
Renewing a Transaction
If the transaction expires before payment is received then you can renew the transaction through the Renew Transaction Endpoint with a new rate signature retrieved from the Payment Methods Endpoint.
Assuming that you had previously booked a transaction with an id of CPS1234, then renewing a transaction would look like:
curl \
-u '<[email protected]>:<service-token>' \
-d '{
"rate_sig":"asdasd123asdasd"
}' \
-H "Content-Type: application/json" \
-X POST \
https://demo.s.portal.cohortgo.com/api/v1/services/payments/transactions/CPS1234/renew
A successful response will return the same content as when you booked the transaction. An example of this might look like:
{
"reference": "CPS1234",
"payment_instructions_url": "https://example.com/payment_instructions.pdf",
"transfer_form": {
"label": "A2 Form",
"description": "Transfer form required when making payments in India",
"download_url": "https://example.com/a2_form.pdf",
"upload_url": "https://example.com/upload_transfer_form"
}
}
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8.2: Angle Pairs
Difficulty Level: At Grade Created by: CK-12
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Lily wants to change the hopscotch design so that each player's foot can only land in half of each box. Her plan is to draw a line from one corner of each box to the diagonal corner of each box. She takes out a protractor to measure half of a corner angle in Box 1. What should be the measure of half of a corner angle?
In this concept, you will learn how to identify and use angle pairs.
Identifying and Using Angle Pairs
Two angles together are angle pairs. Sometimes, the measures of these angles form a special relationship. One special relationship is called complementary angles. Complementary angles are angle pairs that add up to exactly \begin{align*}90^{\text{o}}.\end{align*}90o. In other words, when put together, the two angles form a right angle.
Below are some pairs of complementary angles.
Supplementary angles are two angles that add up to exactly \begin{align*}180^{\text{o}}.\end{align*}180o. When put together, the two angles form a straight angle. Take a look at the pairs of supplementary angles below.
Let’s look at two examples.
Classify the following pairs of angles as either complementary or supplementary.
The sum of the angles in Figure 1 is \begin{align*}180^{\text{o}}.\end{align*}180o. Therefore these angles are supplementary angles.
The sum of the angles in Figure 2 is \begin{align*}90^{\text{o}}.\end{align*}90o. Therefore these angles are complementary angles.
Remember, complementary angles add up to \begin{align*}90^{\text{o}},\end{align*}90o, and supplementary angles add up to \begin{align*}180^{\text{o}}.\end{align*}180o.
Examples
Example 1
Earlier, you were given a problem about Lily, who wants to divide spaces in half by drawing a line from one corner to the diagonal corner.
Lily needs to figure out the value of half of a corner angle. If she divides a \begin{align*}90^{\text{o}}\end{align*}90oangle in half, what type of angles will she form? What will be the value of those angles?
First, what type of angle pair equals \begin{align*}90^{\text{o}}?\end{align*}90o?
Complementary angles
Next, what is the value of half of \begin{align*}90^{\text{o}}\end{align*}90o
\begin{align*}45^{\text{o}}\end{align*}45o
Then, write the size of each angle.
\begin{align*}45^{\text{o}} \! , \ 45^{\text{o}}\end{align*}45o, 45o
The answer is that Lily will create complementary angles that each have a measure of \begin{align*}45^{\text{o}}.\end{align*}45o.
Example 2
Solve the following problem by identifying the angle pair as complementary, supplementary or neither.
Angle \begin{align*}A = 36^{\text{o}} \! ,\end{align*}A=36o, Angle \begin{align*}B = 45^{\text{o}}.\end{align*}B=45o.
First, add the values of the angles.
\begin{align*}36^{\text{o}} + 45^{\text{o}} = 81^{\text{o}}\end{align*}36o+45o=81o
Next, check to see if the sum is \begin{align*}90^{\text{o}}\end{align*}90o or \begin{align*}180^{\text{o}}\end{align*}180o.
The sum is \begin{align*}81^{\text{o}}.\end{align*}81o.
Then, draw a conclusion.
Neither complementary nor supplementary.
The answer is neither.
Identify the following angle pairs as complementary, supplementary or neither.
Example 3
Angle \begin{align*}A = 23^{\text{o}},\end{align*}A=23o, Angle \begin{align*}B = 45^{\text{o}}\end{align*}B=45o
First, add the values of the angles.
\begin{align*}23^{\text{o}} + 45^{\text{o}} = 68^{\text{o}}\end{align*}23o+45o=68o
Next, check to see if the sum is \begin{align*}90^{\text{o}}\end{align*}90o or \begin{align*}180^{\text{o}}.\end{align*}180o.
The sum is \begin{align*}68^o\end{align*}68o
Then, draw a conclusion.
Neither complementary nor supplementary.
The answer is neither.
Example 4
Angle \begin{align*}A = 45^{\text{o}} \!,\end{align*}A=45o, Angle \begin{align*}B = 45^{\text{o}}\!.\end{align*}B=45o.
First, add the values of the angles.
\begin{align*}45^{\text{o}} + 45^{\text{o}} = 90^{\text{o}}\end{align*}45o+45o=90o
Next, check to see if the sum is \begin{align*}90^{\text{o}}\end{align*}90o or \begin{align*}180^{\text{o}} \!.\end{align*}180o.
The sum is \begin{align*}90^{\text{o}} \!.\end{align*}90o.
Then, draw a conclusion.
The angles are complementary.
The answer is complementary angles.
Example 5
Angle \begin{align*}A = 103^{\text{o}} \!,\end{align*}A=103o, Angle \begin{align*}B = 77^{\text{o}}\end{align*}B=77o
First, add the values of the angles.
\begin{align*}103^o + 77^o = 180^o\end{align*}
Next, check to see if the sum is \begin{align*}90^{\text{o}}\end{align*} or \begin{align*}180^{\text{o}}\!.\end{align*}
The sum is \begin{align*}180^{\text{o}}\!.\end{align*}
Then, draw a conclusion.
The angles are supplementary.
The answer is supplementary angles.
Review
Identify whether the pairs below are complementary, supplementary or neither.
1. An angle pair whose sum is \begin{align*}180^{\text{o}}\end{align*}
2. Angle \begin{align*}A = 90^{\text{o}}\end{align*} Angle \begin{align*}B\end{align*} is \begin{align*}45^{\text{o}}\end{align*}
3. Angle \begin{align*}C = 125^{\text{o}}\end{align*} Angle \begin{align*}B = 55^{\text{o}}\end{align*}
4. An angle pair whose sum is \begin{align*}180^{\text{o}}\end{align*}
5. An angle pair whose sum is \begin{align*}245^{\text{o}}\end{align*}
6. An angle pair whose sum is \begin{align*}80^{\text{o}}\end{align*}
7. An angle pair whose sum is \begin{align*}90^{\text{o}}\end{align*}
8. An angle pair whose sum is \begin{align*}55^{\text{o}}\end{align*}
9. An angle pair whose sum is \begin{align*}120^{\text{o}}\end{align*}
10. An angle pair whose sum is \begin{align*}95^{\text{o}}\end{align*}
11. An angle pair whose sum is \begin{align*}201^{\text{o}}\end{align*}
12. An angle pair whose sum is \begin{align*}190^{\text{o}}\end{align*}
Review (Answers)
To see the Review answers, open this PDF file and look for section 8.2.
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Mathematics LibreTexts
5.5: Substitution
• Page ID
80106
• \( \newcommand{\vecs}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \)
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Learning Objectives
• Use substitution to evaluate indefinite integrals.
• Use substitution to evaluate definite integrals.
The Fundamental Theorem of Calculus gave us a method to evaluate integrals without using Riemann sums. The drawback of this method, though, is that we must be able to find an antiderivative, and this is not always easy. In this section we examine a technique, called integration by substitution, to help us find antiderivatives. Specifically, this method helps us find antiderivatives when the integrand is the result of a chain-rule derivative.
At first, the approach to the substitution procedure may not appear very obvious. However, it is primarily a visual task—that is, the integrand shows you what to do; it is a matter of recognizing the form of the function. So, what are we supposed to see? We are looking for an integrand of the form \(f\big[g(x)\big]g′(x)\,dx\). For example, in the integral
\[ ∫(x^2−3)^3 \, 2x \, dx. \label{eq1} \]
we have
\[ f(x)=x^3 \nonumber \]
and
\[g(x)=x^2−3.\nonumber \]
Then
\[ g'(x)=2x.\nonumber \]
and
\[ f[g(x)]g′(x)=(x^2−3)^3(2x),\nonumber \]
and we see that our integrand is in the correct form. The method is called substitution because we substitute part of the integrand with the variable \(u\) and part of the integrand with \(du\). It is also referred to as change of variables because we are changing variables to obtain an expression that is easier to work with for applying the integration rules.
Substitution with Indefinite Integrals
Let \(u=g(x)\),, where \(g′(x)\) is continuous over an interval, let \(f(x)\) be continuous over the corresponding range of \(g\), and let \(F(x)\) be an antiderivative of \(f(x).\) Then,
\[ \begin{align*} ∫f[g(x)]g′(x)\,dx &=∫f(u)\,du \\[4pt] &=F(u)+C \\[4pt] &= F(g(x))+C \end{align*}\]
Proof
Let \(f\), \(g\), \(u\), and \(F\) be as specified in the theorem. Then
\[ \dfrac{d}{dx}\big[F(g(x))\big]=F′(g(x))g′(x)=f[g(x)]g′(x). \nonumber \]
Integrating both sides with respect to \(x\), we see that
\[ ∫f[g(x)]g′(x)\,dx=F(g(x))+C. \nonumber \]
If we now substitute \(u=g(x)\), and \(du=g'(x)\,dx\), we get
\[ ∫f[g(x)]g′(x)\,dx=∫f(u)\,du=F(u)+C=F(g(x))+C. \nonumber \]
Returning to the problem we looked at originally, we let \(u=x^2−3\) and then \(du=2x\,dx\).
Rewrite the integral (Equation \ref{eq1}) in terms of \(u\):
\[ ∫(x^2−3)^3(2x\,dx)=∫u^3\,du. \nonumber \]
Using the power rule for integrals, we have
\[ ∫u^3\,du=\dfrac{u^4}{4}+C. \nonumber \]
Substitute the original expression for \(x\) back into the solution:
\[ \dfrac{u^4}{4}+C=\dfrac{(x^2−3)^4}{4}+C.\nonumber \]
We can generalize the procedure in the following Problem-Solving Strategy.
Problem-Solving Strategy: Integration by Substitution
1. Look carefully at the integrand and select an expression \(g(x)\) within the integrand to set equal to u. Let’s select \(g(x)\). such that \(g′(x)\) is also part of the integrand.
2. Substitute \(u=g(x)\) and \(du=g′(x)dx.\) into the integral.
3. We should now be able to evaluate the integral with respect to \(u\). If the integral can’t be evaluated we need to go back and select a different expression to use as \(u\).
4. Evaluate the integral in terms of \(u\).
5. Write the result in terms of \(x\) and the expression \(g(x).\)
Example \(\PageIndex{1}\): Using Substitution to Find an Antiderivative
Use substitution to find the antiderivative of \(\displaystyle ∫6x(3x^2+4)^4\,dx.\)
Solution
The first step is to choose an expression for \(u\). We choose \(u=3x^2+4\) because then \(du=6x\,dx\) and we already have \(du\) in the integrand. Write the integral in terms of \(u\):
\[ ∫6x(3x^2+4)^4\,dx=∫u^4\,du. \nonumber \]
Remember that \(du\) is the derivative of the expression chosen for \(u\), regardless of what is inside the integrand. Now we can evaluate the integral with respect to \(u\):
\[ ∫u^4\,du=\dfrac{u^5}{5}+C=\dfrac{(3x^2+4)^5}{5}+C.\nonumber \]
Analysis
We can check our answer by taking the derivative of the result of integration. We should obtain the integrand. Picking a value for \(C\) of \(1\), we let \(y=\dfrac{1}{5}(3x^2+4)^5+1.\) We have
\[ y=\dfrac{1}{5}(3x^2+4)^5+1,\nonumber \]
so
\[ \begin{align*} y′ &=\left(\dfrac{1}{5}\right)5(3x^2+4)^46x \\[4pt] &=6x(3x^2+4)^4.\end{align*}\]
This is exactly the expression we started with inside the integrand.
Exercise \(\PageIndex{1}\)
Use substitution to find the antiderivative of \(\displaystyle ∫3x^2(x^3−3)^2\,dx.\)
Hint
Let \(u=x^3−3.\)
Answer
\(\displaystyle ∫3x^2(x^3−3)^2\,dx=\dfrac{1}{3}(x^3−3)^3+C \)
Sometimes we need to adjust the constants in our integral if they don’t match up exactly with the expressions we are substituting.
Example \(\PageIndex{2}\): Using Substitution with Alteration
Use substitution to find the antiderivative of \[ ∫z\sqrt{z^2−5}\,dz. \nonumber \]
Solution
Rewrite the integral as \(\displaystyle ∫z(z^2−5)^{1/2}\,dz.\) Let \(u=z^2−5\) and \(du=2z\,dz.\) Now we have a problem because \(du=2z\,dz\) and the original expression has only \(z\,dz.\) We have to alter our expression for \(du\) or the integral in \(u\) will be twice as large as it should be. If we multiply both sides of the \(du\) equation by \(\dfrac{1}{2}\). we can solve this problem. Thus,
\[ u=z^2−5\nonumber \]
\[ du=2z\,dz \nonumber \]
\[ \dfrac{1}{2}du=\dfrac{1}{2}(2z)\,dz=z\,dz. \nonumber \]
Write the integral in terms of \(u\), but pull the \(\dfrac{1}{2}\) outside the integration symbol:
\[ ∫z(z^2−5)^{1/2}\,dz=\dfrac{1}{2}∫u^{1/2}\,du.\nonumber \]
Integrate the expression in \(u\):
\[ \begin{align*} \dfrac{1}{2}∫u^{1/2}\,du &= \left(\dfrac{1}{2}\right)\dfrac{u^{3/2}}{\dfrac{3}{2}}+C \\[4pt] &= \left(\dfrac{1}{2}\right)\left(\dfrac{2}{3}\right)u^{3/2}+C \\[4pt] &=\dfrac{1}{3}u^{3/2}+C \\[4pt] &=\dfrac{1}{3}(z^2−5)^{3/2}+C \end{align*}\]
Exercise \(\PageIndex{2}\)
Use substitution to find the antiderivative of \(\displaystyle ∫x^2(x^3+5)^9\,dx.\)
Hint
Multiply the du equation by \(\dfrac{1}{3}\).
Answer
\(\displaystyle ∫x^2(x^3+5)^9\,dx = \dfrac{(x^3+5)^{10}}{30}+C \)
Example \(\PageIndex{3}\): Using Substitution with Integrals of Trigonometric Functions
Use substitution to evaluate the integral \(\displaystyle ∫\dfrac{\sin t}{\cos^3t}\,dt.\)
Solution
We know the derivative of \(\cos t\) is \(−\sin t\), so we set \(u=\cos t\). Then \(du=−\sin t\,dt.\)
Substituting into the integral, we have
\[ ∫\dfrac{\sin t}{\cos^3t}\,dt=−∫\dfrac{du}{u^3}.\nonumber \]
Evaluating the integral, we get
\[ −∫\dfrac{du}{u^3}=−∫u^{−3}\,du=−\left(−\dfrac{1}{2}\right)u^{−2}+C.\nonumber \]
Putting the answer back in terms of t, we get
\[ ∫\dfrac{\sin t}{\cos^3t}\,dt=\dfrac{1}{2u^2}+C=\dfrac{1}{2\cos^2t}+C.\nonumber \]
Exercise \(\PageIndex{3}\)
Use substitution to evaluate the integral \( \displaystyle ∫\dfrac{\cos t}{\sin^2t}\,dt.\)
Hint
Use the process from Example \(\PageIndex{3}\) to solve the problem.
Answer
\(\displaystyle ∫\dfrac{\cos t}{\sin^2t}\,dt = −\dfrac{1}{\sin t}+C\)
Exercise \(\PageIndex{4}\)
Use substitution to evaluate the indefinite integral \(\displaystyle ∫\cos^3t\sin t\,dt. \)
Hint
Use the process from Example \(\PageIndex{3}\) to solve the problem.
Answer
\(\displaystyle ∫\cos^3t\sin t\,dt = −\dfrac{\cos^4t}{4}+C \)
Sometimes we need to manipulate an integral in ways that are more complicated than just multiplying or dividing by a constant. We need to eliminate all the expressions within the integrand that are in terms of the original variable. When we are done, \(u\) should be the only variable in the integrand. In some cases, this means solving for the original variable in terms of \(u\). This technique should become clear in the next example.
Example \(\PageIndex{4}\): Finding an Antiderivative Using \(u\)-Substitution
Use substitution to find the antiderivative of \[ ∫\dfrac{x}{\sqrt{x−1}}\,dx. \nonumber \]
Solution
If we let \(u=x−1,\) then \(du=dx\). But this does not account for the \(x\) in the numerator of the integrand. We need to express \(x\) in terms of \(u.\) If \(u=x−1\), then \(x=u+1.\) Now we can rewrite the integral in terms of \(u:\)
\[ ∫\dfrac{x}{\sqrt{x−1}}\,dx=∫\dfrac{u+1}{\sqrt{u}}\,du=∫\left(\sqrt{u}+\dfrac{1}{\sqrt{u}}\right)\,du=∫\left(u^{1/2}+u^{−1/2}\right)\,du.\nonumber \]
Then we integrate in the usual way, replace \(u\) with the original expression, and factor and simplify the result. Thus,
\[ \begin{align*} ∫(u^{1/2}+u^{−1/2})\,du &=\dfrac{2}{3}u^{3/2}+2u^{1/2}+C \\[4pt] &= \dfrac{2}{3}(x−1)^{3/2}+2(x−1)^{1/2}+C \\[4pt] &= (x−1)^{1/2}\left[\dfrac{2}{3}(x−1)+2\right]+C \\[4pt] &= (x−1)^{1/2}\left(\dfrac{2}{3}x−\dfrac{2}{3}+\dfrac{6}{3}\right) \\[4pt] &= (x−1)^{1/2}\left(\dfrac{2}{3}x+\dfrac{4}{3}\right) \\[4pt] &= \dfrac{2}{3}(x−1)^{1/2}(x+2)+C. \end{align*}\]
Substitution for Definite Integrals
Substitution can be used with definite integrals, too. However, using substitution to evaluate a definite integral requires a change to the limits of integration. If we change variables in the integrand, the limits of integration change as well.
Substitution with Definite Integrals
Let \(u=g(x)\) and let \(g'\) be continuous over an interval \([a,b]\), and let \(f\) be continuous over the range of \(u=g(x).\) Then,
\[∫^b_af(g(x))g′(x)\,dx=∫^{g(b)}_{g(a)}f(u)\,du. \nonumber \]
Although we will not formally prove this theorem, we justify it with some calculations here. From the substitution rule for indefinite integrals, if \(F(x)\) is an antiderivative of \(f(x),\) we have
\[ ∫f(g(x))g′(x)\,dx=F(g(x))+C. \nonumber \]
Then
\[\begin{align*} ∫^b_af[g(x)]g′(x)\,dx &= F(g(x))\bigg|^{x=b}_{x=a} \\[4pt] &=F(g(b))−F(g(a)) \\[4pt] &= F(u) \bigg|^{u=g(b)}_{u=g(a)} \\[4pt] &=∫^{g(b)}_{g(a)}f(u)\,du \end{align*}\]
and we have the desired result.
Example \(\PageIndex{5}\): Using Substitution to Evaluate a Definite Integral
Use substitution to evaluate \[ ∫^1_0x^2(1+2x^3)^5\,dx. \nonumber \]
Solution
Let \(u=1+2x^3\), so \(du=6x^2\,dx\). Since the original function includes one factor of \(x^2\) and \(du=6x^2\,dx\), multiply both sides of the \(du\) equation by \(1/6.\) Then,
\[ \begin{align*} du &=6x^2\,dx \\[4pt] \text{becomes}\quad \dfrac{1}{6}du &=x^2\,dx. \end{align*}\]
To adjust the limits of integration, note that when \(x=0,u=1+2(0)=1,\) and when \(x=1,\;u=1+2(1)=3.\)
Then
\[ ∫^1_0x^2(1+2x^3)^5dx=\dfrac{1}{6}∫^3_1u^5\,du. \nonumber \]
Evaluating this expression, we get
\[ \begin{align*} \dfrac{1}{6}∫^3_1u^5\,du &=\left(\dfrac{1}{6}\right)\left(\dfrac{u^6}{6}\right)\Big|^3_1 \\[4pt] &=\dfrac{1}{36}\big[(3)^6−(1)^6\big] \\[4pt] &=\dfrac{182}{9}. \end{align*}\]
Exercise \(\PageIndex{5}\)
Use substitution to evaluate the definite integral \(\displaystyle ∫^0_{−1}y(2y^2−3)^5\,dy. \)
Hint
Use the steps from Example \(\PageIndex{5}\) to solve the problem.
Answer
\(\displaystyle ∫^0_{−1}y(2y^2−3)^5\,dy = \dfrac{91}{3}\)
Exercise \(\PageIndex{6}\)
Use substitution to evaluate \(\displaystyle ∫^1_0x^2 \cos \left(\dfrac{π}{2}x^3\right)\,dx. \)
Hint
Use the process from Example \(\PageIndex{5}\) to solve the problem.
Answer
\(\displaystyle ∫^1_0x^2 \cos \left(\dfrac{π}{2}x^3\right)\,dx = \dfrac{2}{3π}≈0.2122\)
Example \(\PageIndex{6}\): Using Substitution with an Exponential Function
Use substitution to evaluate \[ ∫^1_0xe^{4x^2+3}\,dx. \nonumber \]
Solution
Let \(u=4x^3+3.\) Then, \(du=8x\,dx.\) To adjust the limits of integration, we note that when \(x=0,\,u=3\), and when \(x=1,\,u=7\). So our substitution gives
\[\begin{align*} ∫^1_0xe^{4x^2+3}\,dx &= \dfrac{1}{8}∫^7_3e^u\,du \\[4pt] &=\dfrac{1}{8}e^u\Big|^7_3 \\[4pt] &=\dfrac{e^7−e^3}{8} \\[4pt] &≈134.568 \end{align*}\]
Substitution may be only one of the techniques needed to evaluate a definite integral. All of the properties and rules of integration apply independently, and trigonometric functions may need to be rewritten using a trigonometric identity before we can apply substitution. Also, we have the option of replacing the original expression for \(u\) after we find the antiderivative, which means that we do not have to change the limits of integration. These two approaches are shown in Example \(\PageIndex{7}\).
Example \(\PageIndex{7}\): Using Substitution to Evaluate a Trigonometric Integral
Use substitution to evaluate \[∫^{π/2}_0\cos^2θ\,dθ. \nonumber \]
Solution
Let us first use a trigonometric identity to rewrite the integral. The trig identity \(\cos^2θ=\dfrac{1+\cos 2θ}{2}\) allows us to rewrite the integral as
\[∫^{π/2}_0\cos^2θ\,dθ=∫^{π/2}_0\dfrac{1+\cos2θ}{2}\,dθ. \nonumber \]
Then,
\[ \begin{align*} ∫^{π/2}_0\left(\dfrac{1+\cos2θ}{2}\right)\,dθ &=∫^{π/2}_0\left(\dfrac{1}{2}+\dfrac{1}{2}\cos 2θ\right)\,dθ \\[4pt] &=\dfrac{1}{2}∫^{π/2}_0\,dθ+∫^{π/2}_0\cos2θ\,dθ. \end{align*}\]
We can evaluate the first integral as it is, but we need to make a substitution to evaluate the second integral. Let \(u=2θ.\) Then, \(du=2\,dθ,\) or \(\dfrac{1}{2}\,du=dθ\). Also, when \(θ=0,\,u=0,\) and when \(θ=π/2,\,u=π.\) Expressing the second integral in terms of \(u\), we have
\[ \begin{align*}\dfrac{1}{2}∫^{π/2}_0\,dθ+\dfrac{1}{2}∫^{π/2}_0 \cos 2θ\,dθ &=\dfrac{1}{2}∫^{π/2}_0\,dθ+\dfrac{1}{2}\left(\dfrac{1}{2}\right)∫^π_0 \cos u \,du \\[4pt] &=\dfrac{θ}{2}\,\bigg|^{θ=π/2}_{θ=0}+\dfrac{1}{4}\sin u\,\bigg|^{u=θ}_{u=0} \\[4pt] &=\left(\dfrac{π}{4}−0\right)+(0−0)=\dfrac{π}{4} \end{align*}\]
Key Concepts
• Substitution is a technique that simplifies the integration of functions that are the result of a chain-rule derivative. The term ‘substitution’ refers to changing variables or substituting the variable \(u\) and \(du\) for appropriate expressions in the integrand.
• When using substitution for a definite integral, we also have to change the limits of integration.
Key Equations
• Substitution with Indefinite Integrals \[∫f[g(x)]g′(x)\,dx=∫f(u)\,du=F(u)+C=F(g(x))+C \nonumber \]
• Substitution with Definite Integrals \[∫^b_af(g(x))g'(x)\,dx=∫^{g(b)}_{g(a)}f(u)\,du \nonumber \]
Glossary
change of variables
the substitution of a variable, such as \(u\), for an expression in the integrand
integration by substitution
a technique for integration that allows integration of functions that are the result of a chain-rule derivative
This page titled 5.5: Substitution is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by OpenStax via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.
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Ioannis Kokkinis Ioannis Kokkinis - 1 year ago 109
Javascript Question
return Json.Stringfy result
I have this piece of code :
$.getJSON('http://myjsonurl', function(json){console.log(JSON.stringify(json.columns)); });
This returns in the console all I need from my json response. My aim is to get this value into a function so that I can call it in another place. (For example :
"columns" : getColumns();
So I am making a function like this :
function getColumns() {
$.getJSON('http://myjsonurl', function(json){return JSON.stringify(json.columns); });
}
console.log(getColumns()); // and then call the function in the console log expecting to see the same result as before.
But all I get is undefined.
Why?
UPDATE:
This is how I achieved what I wanted. The following code will reinitiate a datatable based on a json response with data and columns (something not supported natively from datatables). The code will reload the table with new query parameters and includes the buttons plugin :
var theurl;
theurl = "http://myjson.json";
function updateQueryStringParameternondt(key, value) {
var table = $('#datatable-buttons').DataTable();
var ajaxurl = theurl;
var re = new RegExp("([?&])" + key + "=.*?(&|$)", "i");
var separator = ajaxurl.indexOf('?') !== -1 ? "&" : "?";
if (ajaxurl.match(re)) {
console.log( ajaxurl.replace(re, '$1' + key + "=" + value + '$2'));
theurl = ajaxurl.replace(re, '$1' + key + "=" + value + '$2');
table.destroy();
TableManageButtons.init();
}
else {
console.log( ajaxurl + separator + key + "=" + value);
theurl = ajaxurl + separator + key + "=" + value ;
table.destroy();
TableManageButtons.init();
}
}
TableManageButtons.init();
var handleDataTableButtons = function() {
0 !== $("#datatable-buttons").length &&
$.ajax( {
url:theurl,
dataType: 'json',
success: function ( json ) {
$("#datatable-buttons").DataTable({
"data" : json.data,
"columns": json.columns,
dom: "Bfrtip",
buttons: [{
extend: "copy",
className: "btn-sm"
}, {
extend: "csv",
className: "btn-sm"
}, {
extend: "excel",
className: "btn-sm"
}, {
extend: "pdf",
className: "btn-sm"
}, {
extend: "print",
className: "btn-sm"
}],
responsive: !0
});
}
} );
},
TableManageButtons = function() {
"use strict";
return {
init: function() {
handleDataTableButtons();
}
};
}();
Answer
@guest271314 answer is correct and should guide you to resolve the issues regarding returning undefined from getColumns method.
I just want to point out some key things here.
First investigate the plunk I created a moment ago. As you can see all the juice here is to manipulate the Deferred object (See here for more). Rougly explaining, the Deferred object can register callbacks, and if you like multiple ones, chain them, and by invoking them can broadcast their state's as well as their responses. It is based to promises design, so such methods return a promise which can be resolved, synchronous or asynchronous (most of times promises are useful in asynchronous operations).
jQuery's asynchronous methods, like $.ajax return a promise. $.getJSON is no different, as it calls $.ajax in the end which, as mentioned returns a jQuery Deferred Promise.
For jQuery's animation method, see @guest271314 comment below.
More on promise here.
From documentation:
Return a Promise object to observe when all actions of a certain type bound to the collection, queued or not, have finished.
A promise, when handled is either resolved or rejected. resolve stands for success responses, as reject stands for failures. From documentation we can see that there are methods of Deferred object to handle success, failure or both.
deferred.done() Add handlers to be called when the Deferred object is resolved.
deferred.fail() Add handlers to be called when the Deferred object is rejected.
deferred.always() Add handlers to be called when the Deferred object is either resolved or rejected.
So, let's get back to the OP's question. As you can see now from the code:
function getColumns() {
$.getJSON('http://myjsonurl', function(json){return JSON.stringify(json.columns); });
}
There is no way for you to know the getColumns state, because you do not return the promise. When using the $.getJSON handler you essentially handling the response there without emitting the promise object. The getColumns function of course returns undefined because there is not sign of return and by default you get that.
Regarding the deferred.then() method, with this you can handle a promise also, handling its state as well as its progress. In the example code in Plunker I've posted above I do not care about progress, just only the state, so in the first example the promise is handled with the .then() method, with the first function to be the success handler and the second function to be the fail handler. Returning the response from them essentially means the promise gets resolved. I return the promise itself as well.
In the commented out section you can see that you can return only the promise if you'd like and resolve the response in always method
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JURNAL BASIS DATA
Memahami Konsep Jurnal Basis Data
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Kesimpulan
Jurnal basis data sangat penting dalam memastikan keakuratan dan keandalan data pada sistem basis data. Dengan mencatat setiap perubahan yang terjadi pada basis data, jurnal basis data memungkinkan kita untuk melacak setiap transaksi yang terjadi pada sistem. Jurnal basis data juga bisa membantu kita dalam memperbaiki masalah yang mungkin muncul pada sistem. Oleh karena itu, penting untuk selalu mencatat setiap perubahan yang terjadi pada sistem basis data.
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__label__pos
| 0.995672 |
Home Store Docs Blog
Help adding new modules
(Seth) #1
I used the custom image from Ardusub to setup my raspberry pi (which connects to a PixHawk to control the motors). I am able to use mavproxy modules that currently exist to control the motors but I am unable to use new modules. I add them to /MAVProxy/modules and then run setup.py build etc but when I try to load the modules with module load newMod, it doesn’t work. Please help
(Jacob) #2
Can you share your code?
(Seth) #3
I would love to but I am not sure what I am sharing. I tested adding new modules by duplicating the mavproxy_example.py module and changing everywhere where it said example to example2, thus creating the mavproxy_example2.py module.
This is stored in /usr/local/lib/python2.7/dist-packages/MAVProxy/modules
In a prior robot, I was able to then go to /usr/local/lib/python2.7/dist-packages and run the setup.py script:
sudo python setup.py build install --user
to make mavproxy_example2.py usable by mavproxy. However, mavproxy tells me no module: mavproxy_example2.py found which is odd because the statements from setup.py tell me that a byte compiled version of example was created and stored in
copying build/lib.linux-armv7l-2.7/MAVProxy/modules/mavproxy_example2.py -> build/bdist.linux-armv7l/egg/MAVProxy/modules
However after running mavproxy, I used the command module load example2 and received the aforementioned error message.
(Jacob) #4
Please provide the file example2.py and screenshots, or paste of the terminal commands for build install and running mavproxy to show what it looks like to you (directory and everything).
(Seth) #5
Thanks anyways. Solved the issue. called mavproxy.py in a different directory and it solved my issues
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__label__pos
| 0.956391 |
G2A Online Shop
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Tukui » Tukui » Technical Support » I am not sure where to put this
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Posted 4 years ago - #1
4 times reloading now and same bug everytime.
Message: ...terface\AddOns\Tukui\modules\skins\blizzard\help.lua:55: attempt to index field '?' (a nil value)
Time: 04/18/12 08:56:08
Count: 1
Stack: ...terface\AddOns\Tukui\modules\skins\blizzard\help.lua:55: in function `skinfunc'
Interface\AddOns\Tukui\core\functions.lua:588: in function <Interface\AddOns\Tukui\core\functions.lua:571>
Locals: frames = <table> {
1 = "HelpFrameLeftInset"
2 = "HelpFrameMainInset"
3 = "HelpFrameKnowledgebase"
4 = "HelpFrameHeader"
5 = "HelpFrameKnowledgebaseErrorFrame"
}
buttons = <table> {
1 = "HelpFrameAccountSecurityOpenTicket"
2 = "HelpFrameReportLagLoot"
3 = "HelpFrameReportLagAuctionHouse"
4 = "HelpFrameReportLagMail"
5 = "HelpFrameReportLagMovement"
6 = "HelpFrameReportLagSpell"
7 = "HelpFrameReportLagChat"
8 = "HelpFrameReportAbuseOpenTicket"
9 = "HelpFrameOpenTicketHelpTopIssues"
10 = "HelpFrameOpenTicketHelpOpenTicket"
11 = "HelpFrameKnowledgebaseSearchButton"
12 = "HelpFrameKnowledgebaseNavBarHomeButton"
13 = "HelpFrameCharacterStuckStuck"
14 = "GMChatOpenLog"
15 = "HelpFrameTicketSubmit"
16 = "HelpFrameTicketCancel"
}
(for index) = 2
(for limit) = 16
(for step) = 1
i = 2
(*temporary) = nil
(*temporary) = nil
(*temporary) = "CENTER"
(*temporary) = <userdata>
(*temporary) = HelpFrameAccountSecurityOpenTicket {
0 = <userdata>
text = HelpFrameAccountSecurityOpenTicketText {
}
icon = HelpFrameAccountSecurityOpenTicketIcon {
}
selected = HelpFrameAccountSecurityOpenTicketSelected {
}
}
(*temporary) = "OnLeave"
(*temporary) = <function> defined @Interface\AddOns\Tukui\core\functions.lua:326
(*temporary) = nil
(*temporary) = HelpFrameAccountSecurityOpenTicket {
0 = <userdata>
text = HelpFrameAccountSecurityOpenTicketText {
}
icon = HelpFrameAccountSecurityOpenTicketIcon {
}
selected = HelpFrameAccountSecurityOpenTicketSelected {
}
}
(*temporary) = 0.6
(*temporary) = 0.6
(*temporary) = 0.6
(*temporary) = "attempt to index field '?' (a nil value)"
T = <table> {
SkinCheckBox = <function> defined @Interface\AddOns\Tukui\core\functions.lua:536
countOffsets = <table> {
}
SetFontString = <function> defined @Interface\AddOns\Tukui\core\functions.lua:19
Scale = <function> defined @Interface\AddOns\Tukui\core\api.lua:23
PostUpdateAura = <function> defined @Interface\AddOns\Tukui\core\functions.lua:951
AchievementMove = <function> defined @Interface\AddOns\Tukui\modules\blizzard\achievements.lua:18
resolution = "1600x900"
dummy = <function> defined @Interface\AddOns\Tukui\core\init.lua:27
petbuttonsize = 29
UpdateDruidManaText = <function> defined @Interface\AddOns\Tukui\core\functions.lua:1144
StylePet = <function> defined @Interface\AddOns\Tukui\modules\actionbars\Style.lua:142
level = 85
versionnumber = 14.29
StyleActionBarPetAndShiftButton = <function> defined @Interface\AddOns\Tukui\modules\actionbars\Style.lua:87
myrace = "Worgen"
screenwidth = 1600
MicroMenu = <table> {
}
Delay = <function> defined @Interface\AddOns\Tukui\core\functions.lua:285
screenheight = 900
UpdateShards = <function> defined @Interface\AddOns\Tukui\core\functions.lua:1031
PostAchievementMove = <function> defined @Interface\AddOns\Tukui\modules\blizzard\achievements.lua:68
UpdateManaLevel = <function> defined @Interface\AddOns\Tukui\core\functions.lua:1127
AllowFrameMoving = <table> {
}
myclass = "ROGUE"
PP = <function> defined @Interface\AddOns\Tukui\core\functions.lua:29
UnitColor = <table> {
}
ShortValue = <function> defined @Interface\AddOns\Tukui\core\functions.lua:249
MoveUnitFrames = <function> defined @Interface\AddOns\Tukui\modules\unitframes\plugins\oUF_MovableFrames\movable.lua:534
StyleActionBarFlyout = <function> defined @Interface\AddOns\Tukui\modules\actionbars\Style.lua:213
ColorTemplate = <table> {
}
SetModifiedBackdrop = <function> defined @Interface\AddOns\Tukui\core\functions.lua:320
SkinNextPrevButton = <function> defined @Interface\AddOns\Tukui\core\functions.lua:455
CustomCastDelayText = <function> defined @Interface\AddOns\Tuku
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offline
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Posted 4 years ago - #2
With this i am getting severe skinning issues ... like only half the items skinning or just buttons in the window being skinned
3. Gladiator Catok
offline
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XP:
1337 / 1337
Posted 4 years ago - #3
You need to update.
http://www.tukui.org/dl.php
4. Rival Nisha
offline
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XP:
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Posted 4 years ago - #4
Update your Tukui. this i caused by Patch 4.3.4!
5. Gladiator cohesioN
offline
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XP:
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Posted 4 years ago - #5
you can now submit error reports with our new ticket system (this issue has been fixed though as Catok and Nisha said, please update your UI to 14.30)
tickets: http://www.tukui.org/tickets/tukui/
download: http://www.tukui.org/dl.php
"All the world's indeed a stage and we are merely players, performers and portrayers. Each another's audience outside the gilded cage."
6. offline
Member
XP:
4 / 1337
Posted 4 years ago - #6
Thank you any clue when curse client will update?
7. Gladiator Catok
offline
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XP:
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Posted 4 years ago - #7
Downloads? Curse?
GONE! I never really liked to work with Curse for reasons that I won't explain here but this was requested a lot in the past. We decided to give it a shot in July 2011. Unfortunately it was a really bad move. Sure, it's a lot easier for the user to update their favourite user interface, but we are not really happy with their current system for various reasons. One reason that comes to mind is the slow update and approval process. If we need to deploy a quick and urgent fix, it can take up to 1 day before the package is updated and approved on Curse which is really annoying. That's just one example. I'll leave the other reasons out because I want to make this article brief. The only great tool we've seen on Curse was the ticket system, which is something I'll talk about a little later in this blog because we came up with our own solution.
Q: So, no more update from curse client? It was a lot easier for us :(
Yep it was a lot easier for you, but not for us, so... nope! A lot of the time CurseForge was not accessible and it was very annoying for us to deploy updates. We are sorry to come to this decision but it was necessary. At the moment you are still able to download both projects from Curse but they are already outdated and they will be removed in the next couple of days. I know it will affect some people, but this is a decision we are able to live with. Anyway, our users were ok with this back in 2008, 2009 and 2010. If you can't live without an auto-update tool, we've implemented a system, which is already available for use, for a possible auto-update tool. Unfortunately we have so many things to focus on right now so we will not be building it ourselves. We are counting on the community for building a Windows, Linux or Mac auto-update tool. This is something we have seen in the past thanks to some good developers around here so we have no doubt that an application will follow very soon like we saw in the past back in 2009. If you are interested in building such an application, you can private message me for more information about how to query the data on our systems.
http://www.tukui.org/blog/48
8. Challenger TheSamaKutra
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Posted 4 years ago - #8
Darn catok, you beat me to it :)
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| 0.661698 |
Pre-modded Wii
Discussion in 'Wii - Hacking' started by science, Jan 31, 2008.
Jan 31, 2008
Pre-modded Wii by science at 10:43 PM (1,112 Views / 0 Likes) 6 replies
1. science
OP
Member science science rules
Joined:
Jun 9, 2006
Messages:
3,695
Country:
Canada
How much do you think I could get for a Wii premodded with a Wiikey? And would I be able to sell it on ebay?
2. Redsquirrel
Member Redsquirrel GBAtemp Advanced Fan
Joined:
Mar 27, 2007
Messages:
615
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United Kingdom
cant you just wait for a wiikey update next week?
3. science
OP
Member science science rules
Joined:
Jun 9, 2006
Messages:
3,695
Country:
Canada
I don't even want to play Smash Brothers, I just would rather buy a Macbook, and I never ever play my Wii, and I want to sell the Wii at the height of popularity (Smash Brothers)
4. Redsquirrel
Member Redsquirrel GBAtemp Advanced Fan
Joined:
Mar 27, 2007
Messages:
615
Country:
United Kingdom
Ah sorry i did wonder whether it was because of ssbb or not. I think you could still get a lot for it.. RRP + a bit more..
5. stonefry
Member stonefry GBAtemp Regular
Joined:
Aug 16, 2006
Messages:
172
Country:
United States
To answer your question:
No, you can't sell it on ebay. They will yank the auction if it has any reference to a mod.
6. link459
Member link459 GBAtemp Fan
Joined:
Oct 17, 2006
Messages:
354
Country:
United States
You can try craigslist.
7. Traveller
Newcomer Traveller Newbie
Joined:
Feb 1, 2008
Messages:
1
Country:
Australia
Hmm actually I might be interested. How much?
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__label__pos
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This website is for sale for 0.15 BTC Contact us if you are interested.
How Artificial Intelligence (AI) can mix with the Blockchain Technology
0
Artificial Intelligence (AI) and Blockchain are two of the most promising technologies of the 21st century. AI is revolutionizing the way we process information and make decisions, while blockchain is transforming the way we store and transfer value. The combination of these two technologies has the potential to create new and innovative solutions that can have a significant impact on various industries. In this article, we will explore how AI and blockchain can be blended to create a powerful combination that can enhance security, privacy, and efficiency in various applications.
1. Decentralized AI
One of the key advantages of blockchain is its decentralized nature, which makes it more secure and resistant to tampering compared to centralized systems. By combining AI with blockchain, it is possible to create decentralized AI systems that are secure and trustworthy. For example, a decentralized AI system can be used to store and process large amounts of data securely, while ensuring the privacy and confidentiality of the data.
1. Secure and Transparent AI Models
Blockchain technology can also be used to ensure the transparency and security of AI models. With blockchain, it is possible to create a secure and transparent environment for AI models, where data can be shared and verified in a decentralized and transparent manner. This can help to prevent data breaches and ensure that AI models are free from bias and manipulation.
1. AI-Powered Decentralized Applications
One of the most exciting applications of the combination of AI and blockchain is the creation of AI-powered decentralized applications. These applications can use AI to process and analyze data in real-time, while relying on blockchain to ensure the security and transparency of the data. This can lead to new and innovative solutions in various industries, including finance, healthcare, and supply chain management.
1. Tokenizing AI Services
Another important application of the combination of AI and blockchain is the tokenization of AI services. With blockchain, it is possible to create tokens that represent the value of AI services, making it easier to buy and sell AI services in a secure and transparent manner. This can help to create a new market for AI services and make AI more accessible to businesses and individuals.
In conclusion, the combination of AI and blockchain has the potential to create new and innovative solutions that can improve the efficiency, security, and transparency of various applications. The combination of these two technologies is still in its early stages, but it is clear that it has the potential to change the way we use and store data in the future. As the technology continues to evolve, we can expect to see new and exciting applications of AI and blockchain in various industries.
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__label__pos
| 0.992753 |
3
We already have canonical answers on how Close Votes work and how Review queues work. This one is intended to hold one regarding their connection & interaction.
Close votes and Close Review are definitely connected, but the nature of the connection remains a mystery - which leads to confusion.
Specifically, Close votes and close Review votes appear to be one and the same:
• The close reason selection UI is identical
• "Previous votes" seen in the UI in both cases always have have the same number and distribution
• The numbers of both types of votes appear to always be the same
However:
• Sometimes, discrepancies occur between the numbers
• Voting to close initiates Close Review, but finishing the Close Review with "keep" doesn't make the Close Votes disappear
Which is counterintuitive and thus appears to be a bug (which, as the linked question showed, it is not) or a bias in the system.
So, how do the mechanisms interact? Specifically, how are the two close vote types related?
| improve this question | | | | |
2
Close votes are distinct from close Review votes, although the two notions are closely connected. Identical UI makes this even more confusing.
• When a user flags a question for closure / casts the initial close vote
• The question goes into the Close Review queue
• If the user has the close privilege, it also registers a close vote with the stated reason
• regardless of whether the user used the "close" or "flag" link (so, for such users, the two are identical as far as closure is concerned)
• If the user doesn't have the privilege (and thus can only flag), it only sets the suggested close reason for the review item
• When further close votes are cast
• they do not add to close Review votes
• The "previous votes" in the close reason selection UI are taken from existing close votes
• When close Review votes are cast
• they also register as close votes
• The "previous votes" in the close reason selection UI are taken from existing close votes
• When an "Edit" is chosen and submitted from the Review UI while the review is still active
• An Edit vote is registered in review results
• The review is instantly complete with "keep open" result (see below for consequences)
• When the close criteria are met during a review
I.e. (as of this writing) 5 close votes (=(due to the above) 5 votes to close, regardless of their origin) or a binding vote by a ♦ mod (or gold badge holder, if it's a dupe).
• the question is put on hold
• close votes disappear
• review is marked complete, its results can still be viewed
• the review results only show actions taken from the Review UI, not actions taken outside of review, such as close votes cast directly or flags raised
• close reason is selected from close votes (details; (strangely, this doesn't appear to be documented anywhere else))
• When the review reaches consensus to keep open
(As of this writing, this means 3 "keep open" votes or a binding vote by a ♦ mod.)
• review is marked complete etc. (see above)
• existing close votes do not disappear
• but are subject to be aged away
• when another close vote is cast
• a new, empty, Close Votes Review entry is created for the same question. Reason selection UI shows all close votes that still exist.
• if close criteria are met - with "old" and "new" votes combined -
• the question is still closed, ignoring any opposing votes in Review
This essentially makes the system biased towards closing questionable questions. (On a brighter note, this also compensates for the similarly powerful "Edit" Review option.)
(Credits: based on https://meta.stackoverflow.com/a/300851/648265)
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| 0.82931 |
How To Fix The Error object not found In R
The error object not found in R typically occurs when you are trying to access an object (such as a variable, function, or data frame) that doesn’t exist in your current environment.
This can happen for a variety of reasons, making R fail to resolve the reference you provide. This guide will explain how you can fix the error in each case.
How To Fix The Error object not found In R
You mistype the object’s name
There are times you mistype the name of the object you want to use. If the wrong name isn’t available, R will give you an error. This happens more in real life than you might think.
For instance, we create a data frame from the built-in dataset mtcars with the function head(). If we give the resulting data frame the name “df1” but use “df2” later, R will tell you that such an object doesn’t exist:
df1 <- head(mtcars)
df2
Error: object 'df2' not found
Make sure you have spelled the object name correctly and that you are using the correct case, which should be “df1” in the above example.
df1 <- head(mtcars)
df1
Output
You haven’t created the object
Another common scenario is when you use a name of an object that hasn’t been created.
This may happen when you read a tutorial and execute a copied code. It may contain some objects that need to be created first.
For example, in our guide on finding duplicates in R, we demonstrate the capabilities of the function duplicated() with a simple example. In it, we first create a vector called x. When you forget this step and jump to the command with duplicated() right away, it won’t work as intended:
duplicated(x)
Error in duplicated(x) : object 'x' not found
Make sure that you have created the object or imported it into your environment before trying to use it. In this case, follow our example precisely and create x first to make it work:
x <- c(1, 2, 3, 4, 3, 4, 5, 6, 7, 5, 6, 8, 9, 10)
duplicated(x)
Output
[1] FALSE FALSE FALSE FALSE TRUE TRUE FALSE FALSE FALSE TRUE TRUE FALSE FALSE FALSE
You haven’t imported the object
R allows you to save objects into files and load them later. This is a great way to back up your working data and make it available for other sessions.
For instance, you can save the vector x above into an RData file with the save() function:
save(x, file = "x.RData")
But remember that R doesn’t automatically load this file, and therefore the vector x. If you open a new R session and use x right away, you will see the same error:
x
Error: object 'x' not found
Use the load() function to load objects in a file to your R environment when you want to use them:
load("x.RData")
x
Output
[1] 1 2 3 4 3 4 5 6 7 5 6 8 9 10
Summary
The error object not found in R occurs when you give it a name that doesn’t exist in its memory. You should double-check to see whether you have created, loaded, or typed the name the right way.
Posted in R
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__label__pos
| 0.752881 |
US7991780B1 - Performing multiple related searches - Google Patents
Performing multiple related searches Download PDF
Info
Publication number
US7991780B1
US7991780B1 US12116698 US11669808A US7991780B1 US 7991780 B1 US7991780 B1 US 7991780B1 US 12116698 US12116698 US 12116698 US 11669808 A US11669808 A US 11669808A US 7991780 B1 US7991780 B1 US 7991780B1
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US
Grant status
Grant
Patent type
Prior art keywords
plurality
search
results
content items
set
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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US12116698
Inventor
Corin Anderson
Benedict A. Gomes
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Google LLC
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Google LLC
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• GPHYSICS
• G06COMPUTING; CALCULATING; COUNTING
• G06FELECTRIC DIGITAL DATA PROCESSING
• G06F17/00Digital computing or data processing equipment or methods, specially adapted for specific functions
• G06F17/30Information retrieval; Database structures therefor ; File system structures therefor
• G06F17/30861Retrieval from the Internet, e.g. browsers
• G06F17/30864Retrieval from the Internet, e.g. browsers by querying, e.g. search engines or meta-search engines, crawling techniques, push systems
Abstract
A first search is performed in response to a received search query. The first search is based at least in part on a first portion of the search query. In the first search, a first set of content items are searched over to identify a first set of search results. Each result in the first set of search results identifies at least one content item of the first set of content items. A second set of content items for performing a second search is determined based at least in part on one or more of the results in the first set of search results. The second set of content items includes content items not included in the first set of search results. A second search is performed, searching over the second set of content items to identify a second set of search results. The second search is based at least in part on a second portion of the search query. Each result in the second set of search results identifies at least one content item of the second set of content items.
Description
BACKGROUND
This document relates to performing multiple searches.
The rise of the Internet has enabled access to a wide variety of content items, e.g., video and/or audio files, web pages for particular subjects, news articles, etc. Content items of particular interest to a user can be identified by a search engine in response to a query. One example search engine is the Google search engine provided by Google Inc. of Mountain View, Calif., U.S.A. The query can include one or more search terms or phrases, and the search engine can identify and, optionally, rank the content items based on the search terms or phrases in the query and present the content items to the user (e.g., in order according to the rank).
SUMMARY
In one general aspect, a first search is performed in response to a received search query. The first search is based at least in part on a first portion of the search query. In the first search, a first set of content items are searched over to identify a first set of search results. Each result in the first set of search results identifies at least one content item of the first set of content items. A second set of content items, for performing a second search, is determined based at least in part on one or more of the results in the first set of search results. The second set of content items may include content items not included in the first set of search results. A second search is performed, searching over the second set of content items to identify a second set of search results. The second search is based at least in part on a second portion of the search query. Each result in the second set of search results identifies at least one content item of the second set of content items.
Implementations can include one or more of the following features. The second set of content items can be a subset of the first set of content items. The second set of content items can be determined based in part on the second portion of the search query. The first set of content items can be a first set of web pages. Each result in the first set of search results can identify one of the web pages by a web address of the web page.
The second set of content items can be a second set of web pages. The second set of web pages can be determined based on a first result in the first set of results, where the first result identifies a first web page. A web address of the first web page can include a domain name, and a web address of each of the second set of web pages can also include the domain name. The first web page can include a link to each of the second set of web pages. Each of the second set of web pages can include a link to the first web page. The second set of content items can be assets of a content item. The first web page can have a number of assets, and each of the second set of content items can be one of the assets of the first web page.
The first and second portions of the search query can be received together or separately. A graphical user interface can allow entry of the search query on a user machine. The graphical user interface can have a plurality of text boxes, including a first text box and a second text box. The first text box can allow entry of the first portion of the search query, and the second text box can allow entry of the second portion of the search query. The graphical user interface can include a text box for entering a single text string, and receiving a search query can include receiving the text string entered in the text box. The first portion of the search query can be identified based on the received text string. The second portion of the search query can also be identified based on the received text string.
A first graphical user interface can be presented, allowing entry of the first portion of the search query on the user machine, and an identification of the first set of results can be displayed on the user machine. After displaying the identification of the first set of results, a second graphical user interface, allowing entry of the second portion of the search query, can be presented on the user machine. The first set of results and the second set of results can be sent to the user machine.
The details of one or more implementations are set forth in the accompanying drawings and the description below. Other features will be apparent from the description and drawings, and from the claims.
DESCRIPTION OF DRAWINGS
FIG. 1 is a block diagram illustrating an example system for performing multiple related searches.
FIG. 2 is an example screen shot of a graphical user interface for performing multiple related searches.
FIG. 3 is a block diagram illustrating example content items.
FIG. 4 is a flow chart illustrating an example process for performing multiple related searches.
Like reference symbols in the various drawings indicate like elements.
DETAILED DESCRIPTION
Multiple related searches may be used to identify one or more content items of interest to a user more efficiently and/or accurately. Multiple related searches can be performed in sequence, and after the first search, each search in the sequence can be based on the results of one or more earlier searches in the sequence. In some implementations, a second (or subsequent) search identifies content items that were not identified in the first (or a different earlier) search. Each of the multiple related searches can be based on different portions of a search query. A first search may identify a particular web page based on a first portion of a search query (e.g., “Las Vegas hotels”). A second search may be based on a second portion of the search query (e.g., “buffets”) and a particular web page identified by the first search. For example, the second search can, in some cases, search over all web pages that provide a link to (and/or all web pages that are linked to by) the particular web page identified by the first search. As another example, if the particular web page identified by the first search is a home page or another particular page within a website, the second search can search all of the web pages in the website or domain. The user can identify the second portion (and/or subsequent portions) of the search query after reviewing results from a previous search, or a user can identify the second portion (and optionally subsequent portions) of the search query concurrently with the first portion of the search query. The first and second portions of the search query can be entered by the user, for example, in separate text boxes, or the first and second portions of the search query can be identified automatically based on a search query entered by the user, for example, in a single text box.
FIG. 1 is a block diagram illustrating an example system 100 for performing multiple searches. The system 100 includes a server 102 and a client machine 104 in communication over a network 106. The server 102 and the client 104 can also communicate with multiple content providers 108 over the network 106. According to the illustration, the client 104 sends a search query 110 to the server 102, and the server 102 performs multiple related searches based on the query 110. The server 102 can receive the search query 110 as a single transmission, or the server 102 can receive different portions of the search query 110 at different times. For example, the server 102 can perform a first search based on a first part of the search query 110, send search results 112 to the client 104, then receive a second part of the search query, and then perform a second search based on the second part of the search query 110. Each of the multiple searches can identify content items (e.g., web pages, videos, documents) provided by content providers 108. The server 102 may identify, and possibly rank, one or more content items that are related to the search query 110. The server sends search results 112 to the client 104 over the network 106. Based on the search results 112, the client 104 can access one or more of the content items identified by the server 102 during the search. For example, the search results 112 can include links to web pages provided by a content provider 108.
The server 102 can receive, transmit, process and store data related to multiple related searches. In particular, the server 102 can receive a search query 110, perform multiple related searches based on the query 110, and transmit search results 112. The server 102 can be implemented using computers other than servers, as well as a server pool. Server 102 can be any computer, electronic or processing device such as a blade server, a general-purpose personal computer (PC), a Macintosh, a workstation, or a Unix-based computer. The system 100 can include computers other than general purpose computers as well as computers without conventional operating systems. The server 102 can be adapted to execute operating systems including Linux, UNIX, Windows Server, or others. In certain implementations, the server 102 includes or is coupled with a web server and/or a mail server. The various elements of the server 102 can be implemented as a single machine or as multiple machines connected over a network, such as an intranet, the network 106, and/or the Internet.
Server 102 includes a memory 128, a processor 130, and an interface 114. The memory 128 includes machine-readable media for storing information related to multiple searches, including query data 116 and search data 122. The memory 128 can be volatile or non-volatile memory including magnetic media, optical media, random access memory (RAM), read-only memory (ROM), removable media, and/or others. In addition to query data 116 and search data 122, the memory 128 can store other data such as applications or services, firewall policies, a security or access log, HTML files or templates, data classes or object interfaces, child software applications or sub-systems, and others. The memory 128 can additionally store information related to content items, for example, the content items provided by content providers 108.
The query data 116 includes information related to search queries 110 received by the server 102. The query data 116 can include information related to many search queries received from multiple different clients. The query data 116 can include an identification of multiple different parts of the search query 110 for performing multiple searches. For example, the query data 116 can include an identification of a first portion of a search query 110 for performing a first search and an identification of a second (and/or a subsequent) portion of the search query 110 for performing a second (and/or a subsequent) search. The query data 116 can include information related to modifications to the search query 110, such as automatic spelling corrections. The query data 116 can additionally include information about tokens (described below) used in the search query 110. The query data 116 can include information about which client transmitted the query 110 and information about previous queries received from the same client.
The search data 122 includes information provided by the search engine 120, such as information related to search results 112. The search data 122 can include information related to one or more different search queries 110. The search data 122 can include information related to each of multiple related searches that are collectively based on a single search query 110. For example, the search data 122 can include a first set of search results from a search based on a first portion of a search query and a second (and/or a subsequent) set of search results from a search based on a second (and/or a subsequent) portion of the search query. In addition to an identification of the content items identified during a search, the search data 122 can include other information about each content item identified during the search, for example, a web address, a summary of each content item, an identification of pages similar to each content item, a “snippet” (e.g., a short text excerpt) from each content item, a date and/or time when each content item was last updated, a size (e.g., 52 kilobytes) of each content item, a popularity or user rating of each content item, a search score associated with each content item, a listing of links (e.g., hyperlinks) included in each content item, and/or a listing of other content items that link to each of the content items identified during the search.
The processor 130 executes instructions and manipulates data to perform operations of the server 102. Although FIG. 1 illustrates a single processor 130 in the server 102, multiple processors 130 may be used, and reference to processor 130 is meant to include multiple processors 130 where applicable. In the illustrated implementation, processor 130 executes a query analyzer 118, a search engine 120, and a search results analyzer 124, for example, in response to a request or input from a user of server 102 or any appropriate computer system coupled with network 106.
The query analyzer 118 can include any software, hardware, and/or firmware, or combination thereof, operable to process a search query 110. The query analyzer 118 can take as an input the search query 110 and identify multiple portions of the search query 110 for performing multiple related searches. The query analyzer 118 can take as an input a single portion of the search query 110 or an aggregate of all portions of the search query 110. The query analyzer 118 can identify search tokens in the search query 110 (or a portion of the search query 110) and use the search tokens to identify a type of search to be performed. A search token may, for example, indicate an essential term in the search query, a term to exclude from the search, or a type of content item to search for during the search. A search token may, for example, identify the first, second, and/or other portions of the search query 110. The query analyzer 118 can identify misspelled words and/or a probability that a word is misspelled and take appropriate action, such as correcting the misspelled word. The query analyzer 118 can receive information from and send information to the memory 128. For example, the query analyzer 118 can receive a search query 110 from the query data 116, identify a first portion and a second portion of the query 110, and store the output in the query data 116. The query analyzer 118 can send information, such as a search query 110 or a portion of a search query 110, to the search engine 120 and/or to the search results analyzer 124.
The search engine 120 can perform one or more searches for content items based on the search query 110 and/or a portion of the search query 110. In some implementations, the search engine searches the Internet for web pages that most accurately define the term or terms included in a portion of the search query 110. For example, if a first portion of a search query is “Las Vegas hotels,” the search engine 120 can search for web pages that are related to “Las Vegas hotels.” In some implementations, the search engine performs one or more subsequent searches after the first search, and the one or more subsequent searches are based on the results of the first (or another previous) search and/or a second (or subsequent) portion of the search query. For example, if a second portion of the search query is “buffet,” the search engine 120 can search for the term “buffet” in the web sites related to one or more of the first search results. The search engine 120 can search over local data stored in the memory 128 and/or remote data stored by a content provider 108. The search engine 120 can search over information available over any network or other connection available to the server 102. The search engine 120 can receive information from the query analyzer 118 and send information to the memory 128. For example, the search engine 120 can store in the search data 122 information related to web pages identified during a search.
The search results analyzer 124 can process search data 122 and/or query data 116. The search results analyzer 124 can determine a set of content items, or properties of content items, over which to search during a second (or subsequent) search. In some implementations, the search results analyzer 124 takes as an input a first set of search results identified during a first search, and the search results analyzer 124 determines, based at least in part on one or more of the results in the first set of search results, a second set of content items to be searched over in a second search. The search results analyzer 124 may determine the second set of content items by identifying the actual content items (e.g., by a web address) or by identifying a property of the content items. Each content item in the second set of content items can be identified based on its relationship to one or more of the results of the first search. For example, each of the second set of content items can be web pages included in the same website as one of the results from the first search. As another example, each of the second set of content items can be a web page that is linked to by one or more websites identified during the first search. As another example, each of the second set of content items can be a web page that provides a link to one or more websites identified during the first search. As another example, each of the second set of content items can be an asset of a content item identified during the first search. Assets of a content item can include text, images, links, metadata, and other information included in or referenced by the content item.
In some implementations, firmware and/or wired or programmed hardware, alone or in combination with software, may be used in lieu of software. The query analyzer 118, the search engine 120, and the search results analyzer 124, may be written or described in any appropriate computer language including C, C++, Java, J#, Visual Basic, assembler, Perl, any suitable version of 4GL, as well as others. While the query analyzer 118, the search engine 120, and the search results analyzer 124 are illustrated as including individual modules, each may include numerous other sub-modules or may instead be a single multi-tasked module that implements the various features and functionality through various objects, methods, or other processes. Further, while illustrated as internal to server 102, one or more processes associated with the query analyzer 118, the search engine 120, and the search results analyzer 124 may be stored, referenced, or executed remotely. Moreover, the query analyzer 118, the search engine 120, and the search results analyzer 124 may be a child or sub-module of another software module.
The server 102 may also include an interface 114 for communicating with other computer systems, such as the client 104 and the content providers 108, over the network 106 in a client-server or other distributed environment. In certain implementations, the server 102 receives data from internal or external senders through interface 114 for storage in the memory 128 and/or processing by the processor 130. The interface 114 can be implemented as logic encoded in software and/or hardware and operable to communicate with network 106. The interface 114 can include software supporting one or more communications protocols associated with the network 106 or hardware operable to communicate signals.
The client 104 is any device (e.g., computing device) operable to connect or communicate with the server 102 or the network 106. The client 104 can receive, transmit, process, and store data associated with multiple related searches. While the illustrated implementation includes a single client 104, the system 100 may include any number of clients 104 communicably coupled to the network 106. The client 104 may be operated by a single user, by multiple users, or automatically (e.g., executing programmed instructions with little or no human interface). Furthermore, “client”, “user”, and “user machine” may be used interchangeably, as appropriate, to refer to the client machine 104 and/or a user of the client machine 104.
Client 104 can be a personal computer, touch screen terminal, workstation, network computer, kiosk, wireless data port, smart phone, personal data assistant (PDA), one or more processors within these or other devices, or any other suitable processing or electronic device used by an advertiser to access the network 106. For example, client 104 can be a PDA wirelessly connected with an external or unsecured network. In another example, client 104 can be a laptop that includes an input device, such as a keypad, touch screen, mouse, or other device that can accept information, and an output device that conveys search results 112, including digital data, visual information, or GUI 126. Both the input device and output device may include fixed or removable storage media such as a magnetic computer disk, optical storage, flash memory, or other suitable media to both receive input from and provide output to users of clients 104 through the display, namely the client portion of GUI 126.
GUI 126 comprises a graphical user interface operable to allow the user of client 104 to interface with at least a portion of system 100, for example, to enter a search query. A screenshot of an example GUI 126 is provided in FIG. 2. GUI 126 can be an efficient and/or user-friendly presentation of data provided by or communicated within system 100. GUI 126 can include customizable frames or views having interactive fields, text boxes, pull-down lists, and/or buttons operated by the user. GUI 126 can display one or more text boxes for entering a search query and/or search results from a search related to a previously entered search query. For example, the GUI 126 can present two, three, or more text boxes for entering each portion of a multiple-search query. Alternatively, the GUI 126 can present a single text box for entering a first portion of a search query. Then, when search results from the first search query are presented to the user, the GUI 126 can provide a second text box for entering a second portion of the search query. The GUI 126 can be configurable, supporting a combination of tables, graphs, text, and images. The term graphical user interface may be used in the singular or in the plural to describe one or more graphical user interfaces and each of the displays of a particular graphical user interface. For example, the GUI 126 can be implemented using a generic web browser or touch screen that processes information in system 100 and efficiently presents the results to the user. The client 104 can transmit data (e.g., the search query 110) to the server 102 using the web browser (e.g., Microsoft Internet Explorer, Mozilla Firefox, Netscape Navigator), and the client 104 can display data (e.g., search results 112, HTML or XML documents) received from the server over the network 106.
The network 106 facilitates wireless and/or wireline communication between the server 102 and other local or remote entities including the client 104 and the content providers 108. The network 106 can include all or a portion of a secured network. While illustrated as a single network, network 106 may be a continuous network logically divided into various sub-nets or virtual networks. In some implementations, network 106 encompasses any internal or external network, networks, sub-network, or combination thereof operable to facilitate communications between various computing components in system 100. Network 106 may communicate, for example, Internet Protocol (IP) packets, Frame Relay frames, Asynchronous Transfer Mode (ATM) cells, voice, video, data, and other suitable information between network addresses. Network 106 may include one or more local area networks (LANs), radio access networks (RANs), metropolitan area networks (MANs), wide area networks (WANs), all or a portion of the global network known as the Internet, and/or any other communication system or systems at one or more locations.
The content providers 108 are systems or system components providing network access to content items. The content providers 108 can be servers hosting websites, web pages, or other types of information. For example, a search result 112 returned by the server 102 to the client 104 can be a link to a particular web page stored locally by one of the content providers 108. The client 104 can then use the link to access the particular web page.
The search query 110 can be a text string including one or more search terms. A search query 110 can include Boolean operators, search tokens, and/or other types of search-related information. A search query 110 can include multiple portions of the search query 110 for performing multiple related searches. The multiple portions can be transmitted concurrently and include an identification of each of the multiple portions of the query. For example, the search query 110 may include special tokens identifying the first portion and the second portion of the query. In other implementations, the multiple portions are transmitted concurrently with no identification of the first or second portion, and the query analyzer 118 divides the query into multiple portions. Alternatively, the multiple portions can be transmitted separately (e.g., at different times). For example, in some implementations, only the first portion of the search query is initially transmitted, and a second (or subsequent) portion of the query is transmitted later, for example, after presenting results from a search based on the first portion of the search query.
The search results 112 can be an identification of content items found by the search engine 120 during a first, second, or subsequent search. For example, a search result can be a link to (or some other identification of a web address of) a web page, a document, or any other electronic file found during a search. The search results 112 can include any information included in search data 122. For example, the search results 112 can include web addresses, content item summaries, links to other content items that are similar to content items found during the search, content item “snippets”, content item update information, content item size (e.g., 52 kilobytes, 3.4 megabytes) information, search rankings, search scores, particular assets of content items, and/or others. The search results 112 can be an HTML or XML document that includes search result data or a reference or a link to search result data.
In one aspect of operation, the client 104 transmits, over the network 106, the search query 110 to the server 102. The server 102 stores the search query 110 with query data 116. The query analyzer 118 processes the search query 110, identifying a first portion of the query and a second portion of the query. The query analyzer sends the first portion of the query to the search engine 120, and the search engine performs a first search based on the first portion of the query. The search engine 120 stores the results of the first search with the search data 122. The search results analyzer 124 receives the results of the first search and information about a second portion of the search query 110. In some implementations, the information about the second portion of the search query 110 identifies a type of second search to perform. For example, the information about the second portion of the search query 110 can indicate that a second search is to search over all content items that are linked to by at least one of the content items identified during the first search. In other implementations, the type of second search may be predetermined (e.g., based on the initial page used to initiate the search query 110). Based on the received information, the search results analyzer 124 identifies a second set of content items to search over during a second search. The search engine receives the second portion of the search query and an identification of the second set of content items to be searched over. The identification of the second set of content items can be, for example, a property of the second set of content items, such as a domain name. The identification of the second set of content items can be a complete listing, such as web addresses or file names, of each of the second set of content items. The search engine 120 performs the second search and stores the results of the second search with the search data 122. The server 102 transmits, over the network 106, the search results 112 to the client 104.
In another aspect of operation, the client 104 transmits, over the network 106, a portion of the search query 110 to the server 102. The server 102 then performs a search and transmits the results of the first search to the client 104. In response, the client 104 transmits a second portion of the search query 110, and the server 102 performs a second search based on the first search results and the second portion of the search query 110. The client-side process of receiving search results and transmitting subsequent portions of a search query can continue, for example, for a third search, a fourth search, a fifth search, and so on.
FIG. 2 is an illustration of an example GUI 126. The example GUI 126 can be displayed on a monitor or display screen of client 104 of FIG. 1. The GUI 126 provides a text box 202 for entering a first portion of a search query. For example, a user could enter text defining search terms for the first portion of the search query. As illustrated, the first portion of the search query is defined by the text 204 “vintage clothes.” The GUI 126 includes an identification of three search results 206 a, 206 b, and 206 c from the first search. The search results 206 are links to web pages identified, for example, by a search engine based on the first portion of the search query. The GUI 126 also provides a text box 208 for entering a second portion of a search query. For example, after receiving the search results 206 from the first search, the user could enter text defining search terms for the second portion of the search query. As illustrated, the second portion of the search query is defined by the text 210 “jeans.” The GUI 126 includes an identification of search results 212 a-212 h of the second search. The illustrated search results 212 are links to web pages identified, for example, by a search engine based on the second portion of the search query and the results 206 of the first search. Each of the results 212 from the second search is associated with one of the results 206 from the first search. For example, results 212 a, 212 b, and 212 c are associated with result 206 a. The first search identified the result 206 a, the web address “www.rustyzipper.com,” based on the search terms “vintage clothes.” In the second search, all web pages associated with the website “www.rustyzipper.com/” were searched based on the search term “jeans.” The second search identified results including the result 212 a, the web address “www.rustyzipper.com/shop.cfm/rz/type.” In some implementations, a GUI 126 is formatted differently from the example GUI 126 of FIG. 2. For example, a GUI 126 can include multiple text boxes (e.g., two or three text boxes) on the initial search page, where a different portion of the search query is entered into each text box. Alternatively, data entered into a single text box (e.g., on the initial search page) can be analyzed and divided into multiple portions automatically (e.g., by the query analyzer 118).
FIG. 3 is a block diagram 300 illustrating example content items and relationships among the example content items. A first content item is a web page 302 identified by a first search, where the first search is based on a first portion of a search query. A second search can be performed based on a second portion of the search query, and the content items to be searched over during the second search can be determined based on properties of the web page 302. For example, the content items to be searched over during the second search can be web pages 328 a, 328 b, and 328 c, which are linked to by the web page 302. As another example, the content items to be searched over during the second search can be web pages 324 a, 324 b, and 324 c, which provide links to the web page 302. As another example, the content items to be searched over during the second search can be web pages 326 a, 326 b, and 326 c, which have a common domain name as the web page 302. As another example, the content items to be searched over during the second search can be one or more assets 304 of the web page 302.
The web page 302 is an electronic file formatted to be displayed by a web browser or program. The web page 302 has a web address 306 a and a number of assets 304. The web address 306 a includes two constituent parts: a domain name 318 and extensions 320 a. For example, if the web address 306 a is “www.ExampleWebAddressA.com/home/index.html,” then the domain name 318 is “www.ExampleWebAddressA.com,” and the extensions 320 a are “/home/index.html.”Each of the web pages 326 a, 326 b, and 326 c has the same domain name 318, but different extensions 320 b, 320 c, or 320 d. For example, the web page 326 b may have the web address “www.ExampleWebAddressA.com/tools/calendar.html.” Each of the web pages 328 a, 328 b, and 328 c has its own web address that is linked to by the web page 302. The web addresses 306 b, 306 c, and 306 d may or may not have any relationship to the web address 306 a. For example, the web address 306 b could be “web.ExampleWebAddressB.org/index.htm.” Each of the web pages 322 a, 322 b, and 322 c includes a link to the web page 302. For example, the web page 322 a may include multiple links 324 a, and one of the links may identify the web address 306 a (e.g., “www.ExampleWebAddressA.com/home/index.html”).
The assets of web page 302 include text 308, graphics 310, metadata 312, other data 314, and links 316. The text 308 can include the text displayed when the web page 302 is displayed. The graphics 310 can include the graphics displayed when the web page 302 is displayed. For example, graphics may include one or more of the following formats: bitmap, Joint Photographic Experts Group (JPEG), Tagged Image File Format (TIFF), Portable Network Graphics (PNG), Graphics Interchange Format (GIF), Post Script (PS), Encapsulated Post Script (EPS), Portable Document File (PDF), or others. The metadata 312 can include information that is not displayed by a browser but is used, for example, by a search engine to classify the contents of a web page. The links 316 can include hyperlinks or other entities that identify a web address or filename of a content item. Other data 314 can include any other type of information related to the web page 302 such as multimedia files, scripts, executable codes, and/or data.
FIG. 4 is a flow chart illustrating an example process 400 for performing multiple searches in accordance with the present disclosure. The process 400 can be implemented automatically, for example, by a processor executing instructions stored in a machine-readable medium. A user or a server administrator may initiate one or more operations in the process 400, for example by entering a command at a work station.
At 402, at least part of a search query is received. For example, a user of a client machine 104 may enter a search query in a text box provided by a search engine service (e.g., the Google search engine service provided by Google Inc. of Mountain View, Calif., U.S.A.), and the search query can be sent from the client machine and received by a remote server. The text box for entering the search query can be included in a GUI, for example, on a web page provided by the search engine service, and the GUI can be displayed by a browser on the client machine 104. The GUI can include multiple text boxes (e.g., two or three text boxes) for entering multiple parts of the search query at once. Alternatively, the GUI can provide a single text box for entering one or more parts of the search query. In this case, different parts of the search query can be identified either manually by the user (e.g., by tokens in the query or when prompted on a subsequent screen) or automatically by a processor (e.g., based on statistical data).
At 404, a first search is performed based on the first part of the search query. For example, in response to receiving the search query, a server may perform a first search over a first plurality of content items (e.g., web pages) to identify a first set of results for the first search, where each result in the first set of results identifies one of the first plurality of content items. The first plurality of content items can include, for example, all of the content items (e.g., web pages, electronic documents, graphics) provided by one or more content providers over a network (e.g., the Internet). In some implementations, the results of the first search are transmitted to the user after the first search is performed. In other implementations, the results of the first search are not transmitted until after a second or a subsequent search. In other implementations, the results of the first search are not transmitted to the user at all. In some implementations, for example, in the case that only the first part of the search query is received at 402, a second part of the search query is received from the user after the first search is performed. The second part of the search query may be entered by a user, for example, after the user has been shown the results of the first search.
At 406, parameters for a second search are defined based on results of the first search. The parameters for the second search can also be based on a second part of the search query. For example, a server may determine a second plurality of content items for performing the second search, wherein the second plurality of content items includes content items not included in the first set of results. The second plurality of content items can be a subset of the first plurality of content items searched over during the first search, or the second plurality of content items can include content items that were not searched over during the first search. The second plurality of content items may or may not be determined based on the second part of the search query.
For example, the first search (at 404) can be performed, searching over a first set of web pages, and each result from the first search can identify one of the web pages in the first set of web pages. A result can be a web address (or a link including the web address) of one of the web pages in the first set of web pages. The second search can then be performed, searching over a second set of content items. The second set of content items may or may not be web pages. The second set of content items can be determined based on a particular web page (or a particular set of web pages) included in the results of the first search. In some implementations, the particular web page has a web address that includes a domain name, and each of the second set of content items is a web page having a web address that includes the domain name. In some implementations, each of the second plurality of content items is a web page that includes a link to one or more of the web pages included in the results of the first search. In some implementations, each of the second plurality of content items is a web page that is linked to by one or more of the web pages included in the results of the first search. In some implementations, each of the second plurality of content items is an asset (e.g., text, graphics) of one or more of the web pages included in the results of the first search.
At 408, the second search is performed over the second plurality of content items. In some implementations, the second search searches for web pages related to one or more of the results of the first search based on a second portion of the search query. In such an implementation, the second search can add additional results to the results provided by the first search. The second search can be used to locate (and optionally display to the user) links, graphics, and/or specific words or phrases in a web page or a document identified by one of the first search results. The second search can also be used to categorize results of the first search.
In a specific example, a first search returns a number of links to web pages related to “banana nut bread,” and a second search looks for the word “salt” in each of the first search result web pages. After the search results are sent to the client machine, the client machine displays a link to each web page identified by the first search, and near (e.g., below) each link to a web page, each occurrence of the word “salt,” along with the surrounding text, in the web page is displayed.
At 410, the search results are transmitted to the user. The results can include results from the first search and/or the second search. The results can then be displayed to the user, for example, in a GUI.
While the process 400 is discussed with respect to a first search based on a first part of a search query and a second search based on a second part of the search query, any number of related searches can be performed subsequent to the second search, in a manner similar to the second search. For example, a third search could be performed based on a third part of the search query. The third search could additionally be based on the results of the first search and/or the results of the second search.
The invention and all of the functional operations described in this specification can be implemented in digital electronic circuitry, or in computer software, firmware, or hardware, including the structural means disclosed in this specification and structural equivalents thereof, or in combinations of them. The invention can be implemented as one or more computer program products, i.e., one or more computer programs tangibly embodied in an information carrier, e.g., in a machine readable storage device or in a propagated signal, for execution by, or to control the operation of, data processing apparatus, e.g., a programmable processor, a computer, or multiple computers. A computer program (also known as a program, software, software application, or code) can be written in any form of programming language, including compiled or interpreted languages, and it can be deployed in any form, including as a stand alone program or as a module, component, subroutine, or other unit suitable for use in a computing environment. A computer program does not necessarily correspond to a file. A program can be stored in a portion of a file that holds other programs or data, in a single file dedicated to the program in question, or in multiple coordinated files (e.g., files that store one or more modules, sub programs, or portions of code). A computer program can be deployed to be executed on one computer or on multiple computers at one site or distributed across multiple sites and interconnected by a communication network.
The processes and logic flows described in this specification, including the method steps of the invention, can be performed by one or more programmable processors executing one or more computer programs to perform functions of the invention by operating on input data and generating output. The processes and logic flows can also be performed by, and apparatus of the invention can be implemented as, special purpose logic circuitry, e.g., an FPGA (field programmable gate array) or an ASIC (application specific integrated circuit).
Processors suitable for the execution of a computer program include, by way of example, both general and special purpose microprocessors, and any one or more processors of any kind of digital computer. Generally, the processor will receive instructions and data from a read only memory or a random access memory or both. The essential elements of a computer are a processor for executing instructions and one or more memory devices for storing instructions and data. Generally, a computer will also include, or be operatively coupled to receive data from or transfer data to, or both, one or more mass storage devices for storing data, e.g., magnetic, magneto optical disks, or optical disks. Information carriers suitable for embodying computer program instructions and data include all forms of non volatile memory, including by way of example semiconductor memory devices, e.g., EPROM, EEPROM, and flash memory devices; magnetic disks, e.g., internal hard disks or removable disks; magneto optical disks; and CD ROM and DVD-ROM disks. The processor and the memory can be supplemented by, or incorporated in, special purpose logic circuitry.
To provide for interaction with a user, the invention can be implemented on a computer having a display device, e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor, for displaying information to the user and a keyboard and a pointing device, e.g., a mouse or a trackball, by which the user can provide input to the computer. Other kinds of devices can be used to provide for interaction with a user as well; for example, feedback provided to the user can be any form of sensory feedback, e.g., visual feedback, auditory feedback, or tactile feedback; and input from the user can be received in any form, including acoustic, speech, or tactile input.
The invention can be implemented in a computing system that includes a back-end component, e.g., as a data server, or that includes a middleware component, e.g., an application server, or that includes a front-end component, e.g., a client computer having a graphical user interface or a Web browser through which a user can interact with an implementation of the invention, or any combination of such back-end, middleware, or front-end components. The components of the system can be interconnected by any form or medium of digital data communication, e.g., a communication network. Examples of communication networks include a local area network (“LAN”) and a wide area network (“WAN”), e.g., the Internet.
The computing system can include clients and servers. A client and server are generally remote from each other and typically interact through a communication network. The relationship of client and server arises by virtue of computer programs running on the respective computers and having a client-server relationship to each other.
Various modifications may be made without departing from the scope of this specification. For example, many different types of second searches, which have not been specifically described herein, may be implemented in the various embodiments of the present disclosure. Accordingly, other embodiments are within the scope of the following claims.
Claims (26)
1. A computer-implemented method comprising:
receiving a search query;
in response to the search query, performing a first search over a first plurality of content items to identify a first set of results for the first search, the first search based at least in part on a first portion of the search query, each result in the first set of results identifying at least one of the first plurality of content items;
based at least in part on one or more of the results in the first set of results, determining a second plurality of content items for performing a second search, wherein the second plurality of content items includes content items not identified in the first set of results; and
performing the second search over the second plurality of content items to identify a second set of results for the second search, the second search based at least in part on a second portion of the search query, each result in the second set of results identifying at least one of the second plurality of content items.
2. The method of claim 1, wherein the second plurality of content items comprises a subset of the first plurality of content items.
3. The method of claim 1, wherein the second plurality of content items is determined based in part on the second portion of the search query.
4. The method of claim 1, wherein the first plurality of content items comprises a first plurality of web pages and each result in the first set of results identifies one of the plurality of web pages by a web address of the web page.
5. The method of claim 4, wherein the second plurality of content items comprises a second plurality of web pages.
6. The method of claim 5, wherein the second plurality of web pages is determined based on a first result in the first set of results, the first result identifies a first web page by a first web address, the first web address comprises a domain name, and a web address of each of the second plurality of web pages comprises the domain name.
7. The method of claim 5, wherein the second plurality of web pages is determined based on a first result in the first set of results, and the first result identifies a web page that includes a link to each of the second plurality of web pages.
8. The method of claim 5, wherein the second plurality of web pages is determined based on a first result in the first set of results, the first result identifies a first web page, and each of the second plurality of web pages includes a link to the first web page.
9. The method of claim 4, wherein the second plurality of content items is determined based on a first result in the first set of results, the first result identifies a first web page comprising a plurality of assets, and each of the second plurality of content items comprises one of the plurality of assets.
10. The method of claim 1, further comprising presenting a graphical user interface allowing entry of the search query on a user machine.
11. The method of claim 10, wherein the graphical user interface comprises a plurality of text boxes including a first text box and a second text box, the first text box allowing entry of the first portion of the search query, the second text box allowing entry of the second portion of the search query.
12. The method of claim 10, further comprising sending the first set of results and the second set of results to the user machine.
13. The method of claim 10, wherein the graphical user interface comprises a text box for entering a text string, receiving a search query comprises receiving a text string entered in the text box, and the method further comprises:
identifying the first portion of the search query based on the received text string; and
identifying the second portion of the search query based on the received text string.
14. The method of claim 1, wherein receiving a search query comprises receiving the first portion of the search query from a user machine, and the method further comprises:
presenting a first graphical user interface allowing entry of the first portion of the search query on the user machine;
displaying an identification of the first set of results on the user machine;
presenting a second graphical user interface allowing entry of the second portion of the search query on the user machine after displaying the identification of the first set of results; and
receiving the second portion of the search query from the user machine.
15. An article comprising a machine-readable storage medium storing instructions for causing data processing apparatus to perform operations comprising:
receiving a search query;
in response to the search query, performing a first search over a first plurality of content items to identify a first set of results for the first search, the first search based at least in part on a first portion of the search query, each result in the first set of results identifying at least one of the first plurality of content items;
based at least in part on one or more of the results in the first set of results, determining a second plurality of content items for performing a second search, wherein the second plurality of content items includes content items not identified in the first set of results; and
performing the second search over the second plurality of content items to identify a second set of results for the second search, the second search based at least in part on a second portion of the search query, each result in the second set of results identifying at least one of the second plurality of content items.
16. The article of claim 15, wherein the first plurality of content items comprises a first plurality of web pages and each result in the first set of results identifies one of the first plurality of web pages by a web address of the web page.
17. The article of claim 16, wherein the second plurality of content items comprises a second plurality of web pages, the second plurality of web pages is determined based on a first result in the first set of results, the first result identifies a first web page by a first web address, the first web address comprises a domain name, and a web address of each of the second plurality of web pages comprises the domain name.
18. The article of claim 16, wherein the second plurality of content items comprises a second plurality of web pages, the second plurality of web pages is determined based on a first result in the first set of results, and the first result identifies a web page that includes a link to each of the second plurality of web pages.
19. The article of claim 16, wherein the second plurality of content items comprises a second plurality of web pages, the second plurality of web pages is determined based on a first result in the first set of results, the first result identifies a first web page, and each of the second plurality of web pages includes a link to the first web page.
20. The article of claim 16, wherein the second plurality of content items is determined based on a first result in the first set of results, the first result identifies a first web page comprising a plurality of assets, and each of the second plurality of content items comprises one of the plurality of assets.
21. A system comprising one or more servers, the one or more servers comprising data processing apparatus adapted to:
receive a search query;
in response to the search query, perform a first search over a first plurality of content items to identify a first set of results for the first search, the first search based at least in part on a first portion of the search query, each result in the first set of results identifying at least one of the first plurality of content items;
based at least in part on one or more of the results in the first set of results, determine a second plurality of content items for performing a second search, wherein the second plurality of content items includes content items not identified in the first set of results; and
perform the second search over the second plurality of content items to identify a second set of results for the second search, the second search based at least in part on a second portion of the search query, each result in the second set of results identifying at least one of the second plurality of content items.
22. The system of claim 21, wherein the first plurality of content items comprises a first plurality of web pages and each result in the first set of results identifies one of the first plurality of web pages by a web address of the web page.
23. The system of claim 22, wherein the second plurality of content items comprises a second plurality of web pages, the second plurality of web pages is determined based on a first result in the first set of results, the first result identifies a first web page by a first web address, the first web address comprises a domain name, and a web address of each of the second plurality of web pages comprises the domain name.
24. The system of claim 22, wherein the second plurality of content items comprises a second plurality of web pages, the second plurality of web pages is determined based on a first result in the first set of results, and the first result identifies a web page that includes a link to each of the second plurality of web pages.
25. The system of claim 22, wherein the second plurality of content items comprises a second plurality of web pages, the second plurality of web pages is determined based on a first result in the first set of results, the first result identifies a first web page, and each of the second plurality of web pages includes a link to the first web page.
26. The system of claim 22, wherein the second plurality of content items is determined based on a first result in the first set of results, the first result identifies a first web page comprising a plurality of assets, and each of the second plurality of content items comprises one of the plurality of assets.
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Cited By (7)
* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20090083642A1 (en) * 2007-09-21 2009-03-26 Samsung Electronics Co., Ltd. Method for providing graphic user interface (gui) to display other contents related to content being currently generated, and a multimedia apparatus applying the same
US20110218821A1 (en) * 2009-12-15 2011-09-08 Matt Walton Health care device and systems and methods for using the same
US20130080150A1 (en) * 2011-09-23 2013-03-28 Microsoft Corporation Automatic Semantic Evaluation of Speech Recognition Results
US20130113741A1 (en) * 2011-11-08 2013-05-09 Samsung Electronics Co., Ltd. System and method for searching keywords
WO2013119562A1 (en) * 2012-02-06 2013-08-15 Mycare, Llc Methods for searching genomic databases
US8965909B2 (en) * 2012-12-24 2015-02-24 Yahoo! Inc. Type-ahead search optimization
US20160299883A1 (en) * 2015-04-10 2016-10-13 Facebook, Inc. Spell correction with hidden markov models on online social networks
Citations (18)
* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20040138988A1 (en) 2002-12-20 2004-07-15 Bart Munro Method to facilitate a search of a database utilizing multiple search criteria
US6772150B1 (en) 1999-12-10 2004-08-03 Amazon.Com, Inc. Search query refinement using related search phrases
US6876997B1 (en) 2000-05-22 2005-04-05 Overture Services, Inc. Method and apparatus for indentifying related searches in a database search system
US20060010117A1 (en) * 2004-07-06 2006-01-12 Icosystem Corporation Methods and systems for interactive search
US7152057B2 (en) * 2003-06-18 2006-12-19 Microsoft Corporation Utilizing information redundancy to improve text searches
US20060287985A1 (en) 2005-06-20 2006-12-21 Luis Castro Systems and methods for providing search results
US7212996B1 (en) * 2000-04-20 2007-05-01 Jpmorgan Chase Bank, N.A. System and method for dynamic, multivariable comparison of financial products
US20070112759A1 (en) 2005-05-26 2007-05-17 Claria Corporation Coordinated Related-Search Feedback That Assists Search Refinement
US20070266022A1 (en) 2006-05-10 2007-11-15 Google Inc. Presenting Search Result Information
US20080010248A1 (en) * 2006-07-10 2008-01-10 Oracle International Corporation Computer implemented methods and systems to facilitate retrieval and viewing of call center contact and customer information
US20080160490A1 (en) 2006-12-29 2008-07-03 Google Inc. Seeking Answers to Questions
US7430563B2 (en) * 2000-10-06 2008-09-30 Polar Extreme Research Limited System for storing and retrieving data
US7523103B2 (en) 2000-08-08 2009-04-21 Aol Llc Category searching
US20090150343A1 (en) * 2007-12-05 2009-06-11 Kayak Software Corporation Multi-Phase Search And Presentation For Vertical Search Websites
US20090171907A1 (en) * 2007-12-26 2009-07-02 Radovanovic Nash R Method and system for searching text-containing documents
US7672932B2 (en) * 2005-08-24 2010-03-02 Yahoo! Inc. Speculative search result based on a not-yet-submitted search query
US7707220B2 (en) * 2004-07-06 2010-04-27 Icosystem Corporation Methods and apparatus for interactive searching techniques
US7747638B1 (en) * 2003-11-20 2010-06-29 Yahoo! Inc. Techniques for selectively performing searches against data and providing search results
Patent Citations (19)
* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6772150B1 (en) 1999-12-10 2004-08-03 Amazon.Com, Inc. Search query refinement using related search phrases
US7212996B1 (en) * 2000-04-20 2007-05-01 Jpmorgan Chase Bank, N.A. System and method for dynamic, multivariable comparison of financial products
US6876997B1 (en) 2000-05-22 2005-04-05 Overture Services, Inc. Method and apparatus for indentifying related searches in a database search system
US20050240557A1 (en) 2000-05-22 2005-10-27 Overture Services, Inc. Method and apparatus for identifying related searches in a database search system
US7523103B2 (en) 2000-08-08 2009-04-21 Aol Llc Category searching
US7430563B2 (en) * 2000-10-06 2008-09-30 Polar Extreme Research Limited System for storing and retrieving data
US20040138988A1 (en) 2002-12-20 2004-07-15 Bart Munro Method to facilitate a search of a database utilizing multiple search criteria
US7152057B2 (en) * 2003-06-18 2006-12-19 Microsoft Corporation Utilizing information redundancy to improve text searches
US7747638B1 (en) * 2003-11-20 2010-06-29 Yahoo! Inc. Techniques for selectively performing searches against data and providing search results
US7707220B2 (en) * 2004-07-06 2010-04-27 Icosystem Corporation Methods and apparatus for interactive searching techniques
US20060010117A1 (en) * 2004-07-06 2006-01-12 Icosystem Corporation Methods and systems for interactive search
US20070112759A1 (en) 2005-05-26 2007-05-17 Claria Corporation Coordinated Related-Search Feedback That Assists Search Refinement
US20060287985A1 (en) 2005-06-20 2006-12-21 Luis Castro Systems and methods for providing search results
US7672932B2 (en) * 2005-08-24 2010-03-02 Yahoo! Inc. Speculative search result based on a not-yet-submitted search query
US20070266022A1 (en) 2006-05-10 2007-11-15 Google Inc. Presenting Search Result Information
US20080010248A1 (en) * 2006-07-10 2008-01-10 Oracle International Corporation Computer implemented methods and systems to facilitate retrieval and viewing of call center contact and customer information
US20080160490A1 (en) 2006-12-29 2008-07-03 Google Inc. Seeking Answers to Questions
US20090150343A1 (en) * 2007-12-05 2009-06-11 Kayak Software Corporation Multi-Phase Search And Presentation For Vertical Search Websites
US20090171907A1 (en) * 2007-12-26 2009-07-02 Radovanovic Nash R Method and system for searching text-containing documents
Cited By (9)
* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20090083642A1 (en) * 2007-09-21 2009-03-26 Samsung Electronics Co., Ltd. Method for providing graphic user interface (gui) to display other contents related to content being currently generated, and a multimedia apparatus applying the same
US20110218821A1 (en) * 2009-12-15 2011-09-08 Matt Walton Health care device and systems and methods for using the same
US20130080150A1 (en) * 2011-09-23 2013-03-28 Microsoft Corporation Automatic Semantic Evaluation of Speech Recognition Results
US9053087B2 (en) * 2011-09-23 2015-06-09 Microsoft Technology Licensing, Llc Automatic semantic evaluation of speech recognition results
US20130113741A1 (en) * 2011-11-08 2013-05-09 Samsung Electronics Co., Ltd. System and method for searching keywords
WO2013119562A1 (en) * 2012-02-06 2013-08-15 Mycare, Llc Methods for searching genomic databases
US8965909B2 (en) * 2012-12-24 2015-02-24 Yahoo! Inc. Type-ahead search optimization
US20160299883A1 (en) * 2015-04-10 2016-10-13 Facebook, Inc. Spell correction with hidden markov models on online social networks
US10049099B2 (en) * 2015-04-10 2018-08-14 Facebook, Inc. Spell correction with hidden markov models on online social networks
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__label__pos
| 0.734953 |
ihue ihue - 1 year ago 106
Python Question
Execute Selenium Python Code in a For Loop
I have a script call create_cpe.py
It open up firefox and create a cpe.
create_cpe.py
# -*- coding: utf-8 -*-
from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.webdriver.common.keys import Keys
from selenium.webdriver.support.ui import Select
from selenium.common.exceptions import NoSuchElementException
from selenium.common.exceptions import NoAlertPresentException
import unittest, time, re
import random
import requests
class CreateCPE(unittest.TestCase):
def setUp(self):
self.driver = webdriver.Firefox()
self.driver.implicitly_wait(30)
self.base_url = "http://localhost:8888"
self.verificationErrors = []
self.accept_next_alert = True
def test_create_c_p_e(self):
mac = [ 0x00, 0x24, 0x81,
random.randint(0x00, 0x7f),
random.randint(0x00, 0xff),
random.randint(0x00, 0xff) ]
cpe_mac = ':'.join(map(lambda x: "%02x" % x, mac))
cpe_mac = cpe_mac.replace(":","").upper()
rand_cpe_name = "Bunlong's AP " + str(random.randint(2,99))
url = "https://randomuser.me/api/"
data = requests.get(url).json()
add1 = data['results'][0]['location']['street']
city = data['results'][0]['location']['city']
state = data['results'][0]['location']['state']
postcode = data['results'][0]['location']['postcode']
print rand_cpe_name
print cpe_mac
driver = self.driver
driver.get(self.base_url + "/")
driver.find_element_by_id("username").send_keys("[email protected]")
driver.find_element_by_id("password").send_keys("admin")
driver.find_element_by_xpath("//button[@type='submit']").click()
driver.get(self.base_url + "/account/1001/cpe/create")
driver.find_element_by_css_selector(".add-location").click()
driver.find_element_by_name("add1").send_keys(add1)
driver.find_element_by_name("add2").send_keys("")
driver.find_element_by_name("city").send_keys(city)
driver.find_element_by_name("state").send_keys(state)
driver.find_element_by_name("zip").send_keys(postcode)
driver.find_element_by_name("country").send_keys("USA")
driver.find_element_by_css_selector(".btn.btn-primary").click()
driver.find_element_by_name("mac").send_keys(cpe_mac)
driver.find_element_by_name("cpe_name").send_keys(rand_cpe_name)
driver.find_element_by_name("p_ip").send_keys("192.168.9.2")
driver.find_element_by_name("p_netmask").send_keys("255.255.255.0")
driver.find_element_by_name("p_max_user").send_keys("50")
driver.find_element_by_name("dns").send_keys("172.16.0.73")
driver.find_element_by_name("dns2").send_keys("172.16.0.74")
Select(driver.find_element_by_name("g_max_up")).select_by_visible_text("256 Kbps")
Select(driver.find_element_by_name("g_max_down")).select_by_visible_text("2000 Kbps")
driver.find_element_by_name("g_dns2").send_keys("172.16.0.74")
driver.find_element_by_name("g_portal").send_keys("http://www.bunlongheng.com")
driver.find_element_by_name("g_netmask").send_keys("255.255.255.0")
driver.find_element_by_name("g_max_user").send_keys("40")
driver.find_element_by_name("g_dns").send_keys("172.16.0.74")
driver.find_element_by_name("dns2").send_keys("172.16.0.75")
driver.find_element_by_name("g_dns2").send_keys("172.16.0.76")
driver.find_element_by_name("g_ip").send_keys("192.168.9.3")
driver.find_element_by_css_selector("button.btn.btn-success").click()
def is_element_present(self, how, what):
try: self.driver.find_element(by=how, value=what)
except NoSuchElementException as e: return False
return True
def is_alert_present(self):
try: self.driver.switch_to_alert()
except NoAlertPresentException as e: return False
return True
def close_alert_and_get_its_text(self):
try:
alert = self.driver.switch_to_alert()
alert_text = alert.text
if self.accept_next_alert:
alert.accept()
else:
alert.dismiss()
return alert_text
finally: self.accept_next_alert = True
def tearDown(self):
self.driver.quit()
self.assertEqual([], self.verificationErrors)
if __name__ == "__main__":
unittest.main()
It works when I run
python create_cpe.py
Now
I'm take it to the next level.
I'm trying to create a for loop and run that same script
import os
cpe = raw_input("How many CPE you want to create ? : ")
for x in xrange(int(cpe)):
os.system("/Applications/MAMP/htdocs/code/python/create_cpe.py")
print cpe + ' new CPE(s) inserted !'
and I got
from: can't read /var/mail/selenium
from: can't read /var/mail/selenium.webdriver.common.by
from: can't read /var/mail/selenium.webdriver.common.keys
from: can't read /var/mail/selenium.webdriver.support.ui
from: can't read /var/mail/selenium.common.exceptions
from: can't read /var/mail/selenium.common.exceptions
/Applications/MAMP/htdocs/code/python/create_cpe.py: line 8: import: command not found
/Applications/MAMP/htdocs/code/python/create_cpe.py: line 9: import: command not found
/Applications/MAMP/htdocs/code/python/create_cpe.py: line 10: import: command not found
/Applications/MAMP/htdocs/code/python/create_cpe.py: line 12: syntax error near unexpected token `('
/Applications/MAMP/htdocs/code/python/create_cpe.py: line 12: `class CreateCPE(unittest.TestCase):'
Did I missed anything ?
Should I try something elses ?
Why it is not working when I use the for loop to execute it ?
Answer Source
os.system is running it like it's a bash script. The line that runs it should be
os.system("python /Applications/MAMP/htdocs/code/python/create_cpe.py")
|
__label__pos
| 0.993366 |
C# Tuple
I have recently found this C# feature and found it interesting, let’s take a look.
C# tuples are types that you define using a lightweight syntax. Basically, it gives you the opportunity to define data structures with multiple fields without the complexity of using classes.
Please look at the following example.
(string, int) tuple = ("Hello", 1);
Console.WriteLine($"Tuple with elements {tuple.Item1} and {tuple.Item2}.");
// Output:
// Tuple with elements Hello and 1.
Optionally, you can define the field names.
(string Text, int Count) tuple = ("Hello", 1);
Console.WriteLine($"Tuple with elements {tuple.Text} and {tuple.Count}.");
// Output:
// Tuple with elements Hello and 1.
Another interesting feature of tuples is the support for equality operators.
(string Text, int Count) left = ("Hello", 1);
(string Text, int Count) right = ("Hello", 1);
Console.WriteLine(left == right);
// Output:
// True
Also, you can assign tuples to each other. Keep in mind that tuples must have the same number of fields and the values must be implicitly converted.
(int, double) tuple1 = (17, 3.14);
(double First, double Second) tuple2 = (0.0, 1.0);
tuple2 = tuple1;
Console.WriteLine($"{nameof(tuple2)}: {tuple2.First} and {tuple2.Second}");
// Output:
// tuple2: 17 and 3.14
Now, I must say that you should not go crazy with tuples; replacing separate classes with tuples because you will save a few lines of code it is not a good idea, so before implementing tuples in your code base make sure to document their usage for scenarios where they could be helpful without sacrificing your code quality.
A tiny overview at tuples, but share your thoughts.
For more information about tuples visit Tuple types – C# reference | Microsoft Docs.
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|
__label__pos
| 0.99762 |
13.11. OOP Architecture
13.11.1. Boxes and Arrows
../../_images/uml-class-diagram-1.jpg
13.11.2. UML
• Unified Modeling Language
13.11.3. UML Class Diagram
../../_images/uml-class-diagram-2.png
../../_images/uml-class-diagram-3.png
../../_images/uml-class-diagram-4.png
../../_images/uml-class-diagram-5.png
../../_images/uml-class-diagram-6.png
../../_images/uml-class-diagram-7.png
../../_images/uml-class-diagram-8.jpg
../../_images/uml-class-diagram-9.jpg
../../_images/uml-class-diagram-10.png
13.11.4. UML Sequence Diagram
../../_images/uml-sequence-diagram.jpg
13.11.5. Mermaid
• mermaid - Markdown extension
```mermaid
classDiagram
Animal <|-- Duck
Animal <|-- Fish
Animal <|-- Zebra
Animal : +int age
Animal : +String gender
Animal: +isMammal()
Animal: +mate()
class Duck{
+String beakColor
+swim()
+quack()
}
class Fish{
-int sizeInFeet
-canEat()
}
class Zebra{
+bool is_wild
+run()
}
```
|
__label__pos
| 0.995267 |
Verified Commit 0317ef25 authored by Tomasz Maczukin's avatar Tomasz Maczukin
Browse files
Generate table of FF in documentation automatically from the definitions
parent ddb1860f
......@@ -371,6 +371,9 @@ prepare_release_checklist_issue: $(GOPATH_SETUP)
-issue-template-file ".gitlab/issue_templates/Release Checklist.md" \
$(opts)
update_feature_flags_docs: $(GOPATH_SETUP)
go run ./scripts/update-feature-flags-docs/main.go
development_setup:
test -d tmp/gitlab-test || git clone https://gitlab.com/gitlab-org/ci-cd/tests/gitlab-test.git tmp/gitlab-test
if prlctl --version ; then $(MAKE) -C tests/ubuntu parallels ; fi
......
......@@ -26,13 +26,19 @@ change hidden behind the feature flag disabled a corresponding environment varia
## Available feature flags
| Feature flag | Default value | Deprecated | To be removed with | Description |
|--------------------------------------|---------------|------------|--------------------|-------------|
| `FF_K8S_USE_ENTRYPOINT_OVER_COMMAND` | `true` | ✓ | 12.0 | Enables [the fix][mr-1010] for entrypoint configuration when `kubernetes` executor is used. |
| `FF_DOCKER_HELPER_IMAGE_V2` | `false` | ✓ | 12.0 | Enable the helper image to use the new commands when [helper_image](https://docs.gitlab.com/runner/configuration/advanced-configuration.html#the-runnersdocker-section) is specified. This will start using the new API that will be used in 12.0 and stop showing the warning message in the build log. |
| `FF_CMD_DISABLE_DELAYED_ERROR_LEVEL_EXPANSION` | `false` | ✓ | TBA | Disables [EnableDelayedExpansion](https://ss64.com/nt/delayedexpansion.html) for error checking for when using [Window Batch](https://docs.gitlab.com/runner/shells/#windows-batch) shell. |
| `FF_USE_LEGACY_GIT_CLEAN_STRATEGY` | `false` | ✓ | 12.0 | Enables the new strategy for `git clean` that moves the clean operation after checkout and enables support for `GIT_CLEAN_FLAGS` |
| `FF_USE_LEGACY_BUILDS_DIR_FOR_DOCKER` | `false` | ✓ | 13.0 | Enables the new strategy for Docker executor to cache the content of `/builds` directory instead of `/builds/group-org` |
[mr-1010]: https://gitlab.com/gitlab-org/gitlab-runner/merge_requests/1010
<!--
The list of feature flags is created automatically.
If you need to update it, call `make update_feature_flags_docs` in the
root directory of this project.
The flags are defined in `./helpers/feature_flags/flags.go` file.
-->
<!-- feature_flags_list_start -->
| Feature flag | Default value | Deprecated | To be removed with | Description |
|--------------|---------------|------------|--------------------|-------------|
| `FF_K8S_USE_ENTRYPOINT_OVER_COMMAND` | `true` | ✓ | 12.0 | Enables [the fix](https://gitlab.com/gitlab-org/gitlab-runner/merge_requests/1010) for entrypoint configuration when `kubernetes` executor is used |
| `FF_DOCKER_HELPER_IMAGE_V2` | `false` | ✓ | 12.0 | Enable the helper image to use the new commands when [helper_image](https://docs.gitlab.com/runner/configuration/advanced-configuration.html#the-runnersdocker-section) is specified. This will start using the new API that will be used in 12.0 and stop showing the warning message in the build log |
| `FF_CMD_DISABLE_DELAYED_ERROR_LEVEL_EXPANSION` | `false` | ✗ | | Disables [EnableDelayedExpansion](https://ss64.com/nt/delayedexpansion.html) for error checking for when using [Window Batch](https://docs.gitlab.com/runner/shells/#windows-batch) shell |
| `FF_USE_LEGACY_GIT_CLEAN_STRATEGY` | `false` | ✓ | 12.0 | Enables the new strategy for `git clean` that moves the clean operation after checkout and enables support for `GIT_CLEAN_FLAGS` |
| `FF_USE_LEGACY_BUILDS_DIR_FOR_DOCKER` | `false` | ✓ | 13.0 | Enables the new strategy for Docker executor to cache the content of `/builds` directory instead of `/builds/group-org` |
<!-- feature_flags_list_end -->
......@@ -20,6 +20,11 @@ type FeatureFlag struct {
Description string
}
// REMEMBER to update the documentation after adding or removing a feature flag
//
// Please use `make update_feature_flags_docs` to make the update automatic and
// properly formatted. It will replace the existing table with the new one, computed
// basing on the values below
var flags = []FeatureFlag{
{
Name: FFK8sEntrypointOverCommand,
......
package main
import (
"bytes"
"fmt"
"io"
"io/ioutil"
"strings"
"text/template"
"gitlab.com/gitlab-org/gitlab-runner/helpers/featureflags"
)
const (
docsFile = "./docs/configuration/feature-flags.md"
startPlaceholder = "<!-- feature_flags_list_start -->"
endPlaceholder = "<!-- feature_flags_list_end -->"
)
var ffTableTemplate = `{{ placeholder "start" }}
| Feature flag | Default value | Deprecated | To be removed with | Description |
|--------------|---------------|------------|--------------------|-------------|
{{ range $_, $flag := . -}}
| {{ $flag.Name | raw }} | {{ $flag.DefaultValue | raw }} | {{ $flag.Deprecated | tick }} | {{ $flag.ToBeRemovedWith }} | {{ $flag.Description }} |
{{ end -}}
{{ placeholder "end" }}
`
func main() {
fileContent := getFileContent()
tableContent := prepareTable()
newFileContent := replace(fileContent, tableContent)
saveFileContent(newFileContent)
}
func getFileContent() string {
data, err := ioutil.ReadFile(docsFile)
if err != nil {
panic(fmt.Sprintf("Error while reading file %q: %v", docsFile, err))
}
return string(data)
}
func prepareTable() string {
tpl := template.New("ffTable")
tpl.Funcs(template.FuncMap{
"placeholder": func(placeholderType string) string {
switch placeholderType {
case "start":
return startPlaceholder
case "end":
return endPlaceholder
default:
panic(fmt.Sprintf("Undefined placeholder type %q", placeholderType))
}
},
"raw": func(input string) string {
return fmt.Sprintf("`%s`", input)
},
"tick": func(input bool) string {
if input {
return "✓"
}
return "✗"
},
})
tpl, err := tpl.Parse(ffTableTemplate)
if err != nil {
panic(fmt.Sprintf("Error while parsing the template: %v", err))
}
buffer := new(bytes.Buffer)
err = tpl.Execute(buffer, featureflags.GetAll())
if err != nil {
panic(fmt.Sprintf("Error while executing the template: %v", err))
}
return buffer.String()
}
func replace(fileContent string, tableContent string) string {
replacer := newBlockLineReplacer(startPlaceholder, endPlaceholder, fileContent, tableContent)
newContent, err := replacer.Replace()
if err != nil {
panic(fmt.Sprintf("Error while replacing the content: %v", err))
}
return newContent
}
func saveFileContent(newFileContent string) {
err := ioutil.WriteFile(docsFile, []byte(newFileContent), 0644)
if err != nil {
panic(fmt.Sprintf("Error while writing new content for %q file: %v", docsFile, err))
}
}
type blockLineReplacer struct {
startLine string
endLine string
replaceContent string
input *bytes.Buffer
output *bytes.Buffer
startFound bool
endFound bool
}
func (r *blockLineReplacer) Replace() (string, error) {
for {
line, err := r.input.ReadString('\n')
if err == io.EOF {
break
}
if err != nil {
return "", fmt.Errorf("error while reading issue description: %v", err)
}
r.handleLine(line)
}
return r.output.String(), nil
}
func (r *blockLineReplacer) handleLine(line string) {
r.handleStart(line)
r.handleRewrite(line)
r.handleEnd(line)
}
func (r *blockLineReplacer) handleStart(line string) {
if r.startFound || !strings.Contains(line, r.startLine) {
return
}
r.startFound = true
}
func (r *blockLineReplacer) handleRewrite(line string) {
if r.startFound && !r.endFound {
return
}
r.output.WriteString(line)
}
func (r *blockLineReplacer) handleEnd(line string) {
if !strings.Contains(line, r.endLine) {
return
}
r.endFound = true
r.output.WriteString(r.replaceContent)
}
func newBlockLineReplacer(startLine string, endLine string, input string, replaceContent string) *blockLineReplacer {
return &blockLineReplacer{
startLine: startLine,
endLine: endLine,
input: bytes.NewBufferString(input),
output: new(bytes.Buffer),
replaceContent: replaceContent,
startFound: false,
endFound: false,
}
}
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|
__label__pos
| 0.999506 |
Regular Expressions in Oracle
Regular Expressions (RE) are a powerful feature in Oracle. I have found them to be most useful for situations where you need to quickly find some very specific data, or for modifying (string or XML) data that would normally have required many lines of various Oracle function calls and conditional checks, or were simply impossible to do with 1 query statement.
No doubt that REs can make your code more compact, but on the other hand they should also be avoided in queries that are used on a regular basis in a production system. REs can make your queries slower, especially on large tables or when the actual expression becomes more complicated. So use them with caution within an application. However, for reasons such as troubleshooting, one-time queries or updates, etc they could prove extremely useful.
Next RE functions can be used directly in Oracle queries:
• REGEXP_LIKE
• REGEXP_INSTR
• REGEXP_SUBSTR
• REGEXP_REPLACE
These are basically the functions LIKE, INSTR, SUBSTR and REPLACE put on steroids.
Here are some examples. But first, create a table with some test data in it:
create table testtable (recid number, val varchar2(1000));
insert into testtable values (1, 'the dog barks');
insert into testtable values (2, 'the cat does not bark');
insert into testtable values (3, 'the dog sleeps');
insert into testtable values (4, 'the cat sleeps');
Two different non-RE ways to find data that contains the word ‘dog’:
select * from testtable where val like '%dog%';
select * from testtable where instr(val, 'dog') > 0;
Two different RE ways to find data that contains the word ‘dog’:
select * from testtable where regexp_instr(val, 'dog') > 0;
select * from testtable where regexp_substr(val, 'dog')='dog';
The solution with the like clause seems to be the quickest, even faster than the instr solution. Generally, the use of non-RE functions is recommended above the RE based, if possible. In this particular case, the RE functions are a bit of overkill for such kind of simple string matches.
Now let’s select the records that contain the words ‘cat’ or ‘dog’ but not ‘sleep’:
select * from testtable
where val not like '%sleep%'
and regexp_instr(val, 'cat|dog') > 0;
The next update replaces the word ‘the’ at the beginning of each record, by the word ‘a’:
update testtable
set val = regexp_replace(val, '^the ', 'a ');
The data now looks like this:
a dog barks
a cat does not bark
a dog sleeps
a cat sleeps
This update places the last word of each record between quotes (“):
update testtable
set val = regexp_replace(val, ' ([^ ]+)$', ' "\1"');
The new data looks like this:
a dog "barks"
a cat does not "bark"
a dog "sleeps"
a cat "sleeps"
REs can also be useful for searching within XML data. This could be useful if you want
to avoid using the DOM functions in Oracle, as this tends to require more coding and
several extra function calls.
First create a table that can hold XMLType objects (these are basically CLOBs):
create table xmltable (recid number, xml xmltype);
Insert a row with a small XML structure:
insert into xmltable values (1, '<?xml version="1.0"?>
<products>
<item type="book" price="25">title 1</item>
<item type="cd" price="22">michael jackson</item>
<item type="book" price="18">title 2</item>
</products>');
The next query will select the first occurrence of the node that contains a
TextNode with the value ‘jackson’ anywhere in it. The match is case-insensitive.
select regexp_substr(XMLType.getClobVal(xml),
'<item[^>]*>[^<]*JACKSON[^<]*<[^>]*>',
1,1,'in')
from xmltable;
This will return next line:
<item type="cd" price="22">michael jackson</item>
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|
__label__pos
| 0.63351 |
Share
## https://sploitus.com/exploit?id=9182C670-2F82-5C5D-B1A0-5604CAB46BFE
# CVE 2023 29357
## Informations
- Cible SharePoint (Windows Server 2016 avec SharePoint 2019)
```
Login : FSI\Administrateur
Password : Admin123!
IP : 192.168.56.4
Hostname : WIN-HEVUJ4GJMA6
```
- Attanquant Lubuntu (Version 22.04.3)
```
Login : fsi
Password : Admin123!
IP : 192.168.56.3
```
## Mise en place de l'environnement de test
- Lancement de la VM Sharepoint
```
cd "Serveur SharePoint"
vagrant up
```
[Téléchargment de la Box (facultatif)](https://app.vagrantup.com/leiven/boxes/cve-2023-29357-sharepoint)
- Lancement de VM LUbuntu
```
cd "Client LUbuntu"
vagrant up
```
[Téléchargment de la Box (facultatif)](https://app.vagrantup.com/leiven/boxes/cve-2023-29357-lubuntu)
## Exploit
### https://github.com/Chocapikk/CVE-2023-29357
Une fois les machines démarrés, lancer le script python sur la machine attaquante :
```
python3 exploit.py -u http://win-hevujkgjma6/ -v
```
|
__label__pos
| 0.962064 |
Manage scenarios
You can edit or delete a scenario from a workspace, or create a new scenario from an existing scenario.
Note: If the scenario uses a template, it's not updated automatically if the template is updated. To apply the updated template, edit the scenario to re-select the template and then save your changes.
Edit a scenario
1. Ensure that the required workspace is on the Workspace toolbar.
2. Hover over the workspace to view the Workspace menu.
3. Under Workflows click Scenario List.
The Scenarios List page opens. It lists all existing scenarios.
4. Either click the scenario’s name or click Edit.
The scenario opens on the New Message page.
5. Make your changes and click Save Scenario.
Delete one or more scenarios
1. Ensure that the required workspace is on the Workspace toolbar.
2. Hover over the workspace to view the Workspace menu.
3. Under Workflows click Scenario List.
The Scenarios List page opens. It lists all existing scenarios.
4. Select the check box beside the scenarios you want to delete.
5. Click Delete Scenario.
6. Note: If you're deleting only one scenario you can simply click the Delete link beside it instead.
7. Click OK in the message to confirm your action.
Create a new scenario from an existing scenario
You can open an existing scenario and save it with a new name to create a new scenario.
1. Ensure that the required workspace is on the Workspace toolbar.
2. Hover over the workspace to view the Workspace menu.
3. Under Workflows click Scenario List.
The Scenarios List page opens. It lists all existing scenarios.
4. Either click the scenario’s name or click Edit.
The scenario opens on the New Message page.
5. Make any required changes to the scenario.
6. Click Save Scenario As.
The Save Scenario As dialog opens.
7. Enter a new scenario name (maximum of 30 characters, including spaces).
Make it descriptive and easy to differentiate from other scenarios.
8. Enter a new scenario description.
9. In the Permissions field select an option:
• Everyone: Select this option to allow all users with access to the active workspace to perform actions on the scenario (as defined in their Whispir role permissions). For example, View, Edit or Delete.
• Selected Users: Select this option to choose specific users who can perform actions on the scenario.
10. Click Save.
Related links
BACK TO TOP
|
__label__pos
| 0.887141 |
user6313669 user6313669 - 2 months ago 13
Android Question
SIgn IN Sign Up with Sqlite in android .Unable to solve
I am creating sign-in sign up with Sqlite But unable to sign in. While sign up is working. Please help me where is the problem?
Signup is working fine but unable to click Sign in.
MainActivity
import android.app.Activity;
import android.app.Dialog;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class MainActivity extends Activity {
EditText editTextUserName, editTextPassword;
Button btnSignIn, btnSignUp;
// String userName,password;
LoginDataBaseAdapter loginDataBaseAdapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// create a instance of SQLite Database
loginDataBaseAdapter = new LoginDataBaseAdapter(this);
loginDataBaseAdapter = loginDataBaseAdapter.open();
btnSignIn = (Button) findViewById(R.id.buttonSignIn);
btnSignUp = (Button) findViewById(R.id.buttonSignUp);
// Get The Refference Of Buttons
// Set OnClick Listener on SignUp button
btnSignUp.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
// TODO Auto-generated method stub
/// Create Intent for SignUpActivity abd Start The Activity
Intent intentSignUP = new Intent(getApplicationContext(), SignupActivity.class);
startActivity(intentSignUP);
}
});
}
// Methos to handleClick Event of Sign In Button
public void SignIn(View V)
{
final Dialog dialog = new Dialog(MainActivity.this);
dialog.setContentView(R.layout.signin);
dialog.setTitle("Login");
// get the Refferences of views
final EditText editTextUserName=(EditText)dialog.findViewById(R.id.editTextUserNameToLogin);
final EditText editTextPassword=(EditText)dialog.findViewById(R.id.editTextPasswordToLogin);
Button btnSignIn=(Button)dialog.findViewById(R.id.buttonSignIn);
// Set On ClickListener
btnSignIn.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
// get The User name and Password
String userName=editTextUserName.getText().toString();
String password=editTextPassword.getText().toString();
// fetch the Password form database for respective user name
String storedPassword=loginDataBaseAdapter.getSinlgeEntry(userName);
// check if the Stored password matches with Password entered by user
if(password.equals(storedPassword))
{
Toast.makeText(MainActivity.this, "Congrats: Login Successfull", Toast.LENGTH_LONG).show();
dialog.dismiss();
}
else
{
Toast.makeText(MainActivity.this, "User Name or Password does not match", Toast.LENGTH_LONG).show();
}
}
});
dialog.show();
}
@Override
protected void onDestroy() {
super.onDestroy();
// Close The Database
loginDataBaseAdapter.close();
}
}
activity_main
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TextView
android:id="@+id/Mobileno"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="60dp"
android:layout_gravity="center"
android:textSize="20dp"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:text="@string/Registeresd_Mobile_Number"/>
<EditText
android:id="@+id/editTextUserName"
android:hint="User Name"
android:layout_marginTop="20dp"
android:layout_gravity="center"
android:textSize="15dp"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
</EditText>
<View
android:layout_width="300dp"
android:layout_height="2dp"
android:layout_marginTop="20dp"
android:layout_marginLeft="15dp"
android:layout_marginRight="15dp"
android:layout_gravity="center"
android:background="#c0c0c0"></View>
<TextView
android:id="@+id/editTextPassword"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="20dp"
android:layout_gravity="center"
android:textSize="20dp"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:text="@string/password"/>
<EditText
android:id="@+id/editTextPasswordToLogin"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:layout_gravity="center"
android:maxLength="20"
android:inputType="textPassword"
android:hint="Password" />
<View
android:layout_width="300dp"
android:layout_height="2dp"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:layout_marginTop="20dp"
android:layout_gravity="center"
android:background="#c0c0c0"></View>
<Button
android:id="@+id/buttonSignIn"
android:layout_marginTop="20dp"
android:color="#7EC0EE"
android:layout_width="fill_parent"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:layout_height="wrap_content"
android:background="@drawable/rounded_edittext"
android:clickable="true"
android:text="Sign In" />
<TextView
android:id="@+id/Signup"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="20dp"
android:layout_gravity="center"
android:textSize="15dp"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:clickable="true"
android:text="@string/signup"/>
<Button
android:id="@+id/buttonSignUp"
android:layout_marginTop="20dp"
android:color="#7EC0EE"
android:layout_width="fill_parent"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:layout_height="wrap_content"
android:background="@drawable/rounded_edittext"
android:text="Sign Up" />
</LinearLayout>
Signup
<?xml version="1.0" encoding="utf-8"?>
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:fillViewport="false"
>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:gravity="center_vertical" >
<TextView
android:id="@+id/username"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="20dp"
android:layout_gravity="center"
android:textSize="20dp"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:text="@string/username"/>
<EditText
android:id="@+id/editTextUserName"
android:hint="User Name"
android:layout_marginTop="20dp"
android:layout_gravity="center"
android:textSize="15dp"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
</EditText>
<View
android:layout_width="300dp"
android:layout_height="2dp"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:layout_marginTop="20dp"
android:layout_gravity="center"
android:background="#c0c0c0"></View>
<TextView
android:id="@+id/Email"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="20dp"
android:layout_gravity="center"
android:textSize="20dp"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:text="@string/Email"/>
<EditText
android:id="@+id/emailid"
android:hint="Emailid"
android:layout_marginTop="20dp"
android:layout_gravity="center"
android:textSize="15dp"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
</EditText>
<View
android:layout_width="300dp"
android:layout_height="2dp"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:layout_marginTop="20dp"
android:layout_gravity="center"
android:background="#c0c0c0"></View>
<TextView
android:id="@+id/Contact"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="20dp"
android:layout_gravity="center"
android:textSize="20dp"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:text="@string/contact"/>
<EditText
android:id="@+id/ContactNumber"
android:hint="Contact Number"
android:layout_marginTop="20dp"
android:layout_gravity="center"
android:textSize="15dp"
android:maxLength="10"
android:inputType="number"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
</EditText>
<View
android:layout_width="300dp"
android:layout_height="2dp"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:layout_marginTop="20dp"
android:layout_gravity="center"
android:background="#c0c0c0"></View>
<TextView
android:id="@+id/Password1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="20dp"
android:layout_gravity="center"
android:textSize="20dp"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:text="@string/password1"/>
<EditText
android:id="@+id/editTextPassword"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="20dp"
android:layout_gravity="center"
android:textSize="15dp"
android:maxLength="20"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:hint="Password"
android:inputType="textPassword" />
<View
android:layout_width="300dp"
android:layout_height="2dp"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:layout_marginTop="20dp"
android:layout_gravity="center"
android:background="#c0c0c0"></View>
<TextView
android:id="@+id/confirmPassword1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="20dp"
android:layout_gravity="center"
android:textSize="20dp"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:text="@string/confirmpassword1"/>
<EditText
android:id="@+id/editTextConfirmPassword"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_marginLeft="20dp"
android:layout_marginTop="20dp"
android:layout_marginRight="20dp"
android:hint="Confirm Password"
android:maxLength="20"
android:inputType="textPassword" />
<Button
android:id="@+id/buttonCreateAccount"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Create Account"
android:layout_marginBottom="60dp"
android:layout_marginLeft="20dp"
android:layout_marginTop="20dp"
android:layout_marginRight="20dp"
android:background="@drawable/rounded_edittext"/>
</LinearLayout>
</ScrollView>
Signup
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class SignupActivity extends Activity
{
EditText editTextUserName,editTextPassword,editTextConfirmPassword,emailid,ContactNumber;
Button btnCreateAccount;
LoginDataBaseAdapter loginDataBaseAdapter;
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.signup);
// get Instance of Database Adapter
loginDataBaseAdapter=new LoginDataBaseAdapter(this);
loginDataBaseAdapter=loginDataBaseAdapter.open();
// Get Refferences of Views
editTextUserName=(EditText)findViewById(R.id.editTextUserName);
editTextPassword=(EditText)findViewById(R.id.editTextPassword);
editTextConfirmPassword=(EditText)findViewById(R.id.editTextConfirmPassword);
emailid=(EditText)findViewById(R.id.emailid);
ContactNumber=(EditText)findViewById(R.id.ContactNumber);
btnCreateAccount=(Button)findViewById(R.id.buttonCreateAccount);
btnCreateAccount.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
// TODO Auto-generated method stub
String userName=editTextUserName.getText().toString();
String password=editTextPassword.getText().toString();
String confirmPassword=editTextConfirmPassword.getText().toString();
String id=emailid.getText().toString();
String number= ContactNumber.getText().toString();
// check if any of the fields are vaccant
if(userName.equals("")||password.equals("")||confirmPassword.equals(""))
{
Toast.makeText(getApplicationContext(), "Field Vaccant", Toast.LENGTH_LONG).show();
return;
}
// check if both password matches
if(!password.equals(confirmPassword))
{
Toast.makeText(getApplicationContext(), "Password does not match", Toast.LENGTH_LONG).show();
return;
}
/* if(!emailid(isValidEmail(charSequence target)))
{
}*/
else
{
// Save the Data in Database
loginDataBaseAdapter.insertEntry(number, password);
Toast.makeText(getApplicationContext(), "Account Successfully Created ", Toast.LENGTH_LONG).show();
}
}
});
}
public final static boolean isValidEmail(CharSequence target) {
if (target == null) {
return false;
} else {
return android.util.Patterns.EMAIL_ADDRESS.matcher(target).matches();
}
}
@Override
protected void onDestroy() {
// TODO Auto-generated method stub
super.onDestroy();
loginDataBaseAdapter.close();
}
}
logindatabaseadapter
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
public class LoginDataBaseAdapter
{
static final String DATABASE_NAME = "login.db";
static final int DATABASE_VERSION = 1;
public static final int NAME_COLUMN = 1;
// TODO: Create public field for each column in your table.
// SQL Statement to create a new database.
static final String DATABASE_CREATE = "create table "+"LOGIN"+
"( " +"ID"+" integer primary key autoincrement,"+ "USERNAME text,PASSWORD text); ";
// Variable to hold the database instance
public SQLiteDatabase db;
// Context of the application using the database.
private final Context context;
// Database open/upgrade helper
private DataBaseHelper dbHelper;
public LoginDataBaseAdapter(Context _context)
{
context = _context;
dbHelper = new DataBaseHelper(context, DATABASE_NAME, null, DATABASE_VERSION);
}
public LoginDataBaseAdapter open() throws SQLException
{
db = dbHelper.getWritableDatabase();
return this;
}
public void close()
{
db.close();
}
public SQLiteDatabase getDatabaseInstance()
{
return db;
}
public void insertEntry(String userName,String password)
{
ContentValues newValues = new ContentValues();
// Assign values for each row.
newValues.put("USERNAME", userName);
newValues.put("PASSWORD",password);
// Insert the row into your table
db.insert("LOGIN", null, newValues);
///Toast.makeText(context, "Reminder Is Successfully Saved", Toast.LENGTH_LONG).show();
}
public int deleteEntry(String UserName)
{
//String id=String.valueOf(ID);
String where="USERNAME=?";
int numberOFEntriesDeleted= db.delete("LOGIN", where, new String[]{UserName}) ;
// Toast.makeText(context, "Number fo Entry Deleted Successfully : "+numberOFEntriesDeleted, Toast.LENGTH_LONG).show();
return numberOFEntriesDeleted;
}
public String getSinlgeEntry(String userName)
{
Cursor cursor=db.query("LOGIN", null, " USERNAME=?", new String[]{userName}, null, null, null);
if(cursor.getCount()<1) // UserName Not Exist
{
cursor.close();
return "NOT EXIST";
}
cursor.moveToFirst();
String password= cursor.getString(cursor.getColumnIndex("PASSWORD"));
cursor.close();
return password;
}
public void updateEntry(String userName,String password)
{
// Define the updated row content.
ContentValues updatedValues = new ContentValues();
// Assign values for each row.
updatedValues.put("USERNAME", userName);
updatedValues.put("PASSWORD",password);
String where="USERNAME = ?";
db.update("LOGIN",updatedValues, where, new String[]{userName});
}
}
databasehelper
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
/**
* Created by Neha Thakur on 5/23/2016.
*/
public class DataBaseHelper extends SQLiteOpenHelper
{
public DataBaseHelper(Context context, String name, SQLiteDatabase.CursorFactory factory, int version)
{
super(context, name, factory, version);
}
// Called when no database exists in disk and the helper class needs
// to create a new one.
@Override
public void onCreate(SQLiteDatabase _db)
{
_db.execSQL(LoginDataBaseAdapter.DATABASE_CREATE);
}
// Called when there is a database version mismatch meaning that the version
// of the database on disk needs to be upgraded to the current version.
@Override
public void onUpgrade(SQLiteDatabase _db, int _oldVersion, int _newVersion)
{
// Log the version upgrade.
Log.w("TaskDBAdapter", "Upgrading from version " +_oldVersion + " to " +_newVersion + ", which will destroy all old data");
// Upgrade the existing database to conform to the new version. Multiple
// previous versions can be handled by comparing _oldVersion and _newVersion
// values.
// The simplest case is to drop the old table and create a new one.
_db.execSQL("DROP TABLE IF EXISTS " + "TEMPLATE");
// Create a new one.
onCreate(_db);
}
}
Signin
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TextView
android:id="@+id/Mobileno"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="60dp"
android:layout_gravity="center"
android:textSize="20dp"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:text="@string/Registeresd_Mobile_Number"/>
<EditText
android:id="@+id/editTextUserNameToLogin"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:layout_gravity="center"
android:inputType="number"
android:maxLength="10"
android:hint="Mobile Number">
</EditText>
<View
android:layout_width="300dp"
android:layout_height="2dp"
android:layout_marginTop="20dp"
android:layout_marginLeft="15dp"
android:layout_marginRight="15dp"
android:layout_gravity="center"
android:background="#c0c0c0"></View>
<TextView
android:id="@+id/editTextPassword"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="20dp"
android:layout_gravity="center"
android:textSize="20dp"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:text="@string/password"/>
<EditText
android:id="@+id/editTextPasswordToLogin"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:layout_gravity="center"
android:maxLength="20"
android:inputType="textPassword"
android:hint="Password" />
<View
android:layout_width="300dp"
android:layout_height="2dp"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:layout_marginTop="20dp"
android:layout_gravity="center"
android:background="#c0c0c0"></View>
<Button
android:id="@+id/buttonSignIn"
android:layout_marginTop="20dp"
android:color="#7EC0EE"
android:layout_width="fill_parent"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:layout_height="wrap_content"
android:background="@drawable/rounded_edittext"
android:text="Sign In" />
</LinearLayout>
Answer
Add onClick method also to your signIn button.
<Button
android:id="@+id/buttonSignIn"
android:layout_marginTop="20dp"
android:color="#7EC0EE"
android:layout_width="fill_parent"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:layout_height="wrap_content"
android:background="@drawable/rounded_edittext"
<!-- Here -->
android:onClick="SignIn"
android:clickable="true"
android:text="Sign In" />
|
__label__pos
| 0.969167 |
技术文章 > 在Visual C#中使用XML指南之读取XML
在Visual C#中使用XML指南之读取XML
2018-11-14 15:22
文档管理软件，文档管理系统，知识管理系统，档案管理系统的技术资料：
对于XML，想必各位都比较了解，我也就不用费笔墨来描述它是什么了，我想在未来的Web开发中XML一定会大放异彩，XML是可扩展标记语言，使用它企业可以制定一套自己的数据格式，数据按照这种格式在网络中传输然后再通过XSLT将数据转换成用户期望的样子表示出来，这样便轻易的解决了数据格式不兼容的问题。用于Internet的数据传输，我想，这是XML对于我们这些程序员最诱人的地方！
我们今天的主题不是论述XML的好处，而是讨论在C#中如何使用XML。下面我们来了解一下使用程序访问XML的一些基础理论知识。
访问的两种模型：
在程序中访问进而操作XML文件一般有两种模型，分别是使用DOM（文档对象模型）和流模型，使用DOM的好处在于它允许编辑和更新XML文档，可以随机访问文档中的数据，可以使用XPath查询，但是，DOM的缺点在于它需要一次性的加载整个文档到内存中，对于大型的文档，这会造成资源问题。流模型很好的解决了这个问题，因为它对XML文件的访问采用的是流的概念，也就是说，任何时候在内存中只有当前节点，但它也有它的不足，它是只读的，仅向前的，不能在文档中执行向后导航操作。虽然是各有千秋，但我们也可以在程序中两者并用实现优劣互补嘛，呵呵，这是题外话了！我们今天主要讨论XML的读取，那我们就详细讨论一下流模型吧！
流模型中的变体：
流模型每次迭代XML文档中的一个节点，适合于处理较大的文档，所耗内存空间小。流模型中有两种变体——"推”模型和"拉”模型。
推模型也就是常说的SAX，SAX是一种靠事件驱动的模型，也就是说：它每发现一个节点就用推模型引发一个事件，而我们必须编写这些事件的处理程序，这样的做法非常的不灵活，也很麻烦。
.NET中使用的是基于"拉”模型的实现方案，"拉”模型在遍历文档时会把感兴趣的文档部分从读取器中拉出，不需要引发事件，允许我们以编程的方式访问文档，这大大的提高了灵活性，在性能上"拉”模型可以选择性的处理节点，而SAX每发现一个节点都会通知客户机，从而，使用"拉”模型可以提高Application的整体效率。在.NET中"拉”模型是作为XmlReader类实现的，下面看一下该类的继承结构：
我们今天来讲一下该体系结构中的XmlTextReader类，该类提供对Xml文件进行读取的功能，它可以验证文档是否格式良好，如果不是格式良好的Xml文档，该类在读取过程中将会抛出XmlException异常，可使用该类提供的一些方法对文档节点进行读取，筛选等操作以及得到节点的名称和值，请牢记：XmlTextReader是基于流模型的实现，打个不恰当的比喻，XML文件就好象水源，闸一开水就流出，流过了就流过了不会也不可以往回流。内存中任何时候只有当前节点，你可以使用XmlTextReader类的Read()方法读取下一个节点。好了，说了这么多来看一个例子，编程要注重实际对吧。看代码前先看下运行效果吧！
Example1按纽遍历文档读取数据，Example2，Example3按纽得到节点类型，Example4过滤文档只获得数据内容，Example5得到属性节点，Example6按纽得到命名空间，Example7显示整个XML文档，为此，我专门写一个类来封装以上功能，该类代码如下：
[code]
csharp
//---------------------------------------------------------------------------------------------------
//XmlReader类用于Xml文件的一般读取操作，以下对这个类做简单介绍：
//
//Attributes(属性):
//listBox: 设置该属性主要为了得到客户端控件以便于显示所读到的文件的内容(这里是ListBox控件)
//xmlPath: 设置该属性为了得到一个确定的Xml文件的绝对路径
//
//Basilic Using(重要的引用):
//System.Xml: 该命名空间中封装有对Xml进行操作的常用类，本类中使用了其中的XmlTextReader类
//XmlTextReader: 该类提供对Xml文件进行读取的功能，它可以验证文档是否格式良好，如果不是格式 // 良好的Xml文档，该类在读取过程中将会抛出XmlException异常，可使用该类提供的
// 一些方法对文档节点进行读取，筛选等操作以及得到节点的名称和值
//
//bool XmlTextReader.Read(): 读取流中下一个节点，当读完最后一个节点再次调用该方法该方法返回false
//XmlNodeType XmlTextReader.NodeType: 该属性返回当前节点的类型
// XmlNodeType.Element 元素节点
// XmlNodeType.EndElement 结尾元素节点
// XmlNodeType.XmlDeclaration 文档的第一个节点
// XmlNodeType.Text 文本节点
//bool XmlTextReader.HasAttributes: 当前节点有没有属性，返回true或false
//string XmlTextReader.Name: 返回当前节点的名称
//string XmlTextReader.Value: 返回当前节点的值
//string XmlTextReader.LocalName: 返回当前节点的本地名称
//string XmlTextReader.NamespaceURI: 返回当前节点的命名空间URI
//string XmlTextReader.Prefix: 返回当前节点的前缀
//bool XmlTextReader.MoveToNextAttribute(): 移动到当前节点的下一个属性
//---------------------------------------------------------------------------------------------------
namespace XMLReading
{
using System;
using System.Xml;
using System.Windows.Forms;
using System.ComponentModel;
/// ＜summary＞
/// Xml文件读取器
/// ＜/summary＞
public class XmlReader : IDisposable
{
private string _xmlPath;
private const string _errMsg = "Error Occurred While Reading ";
private ListBox _listBox;
private XmlTextReader xmlTxtRd;
#region XmlReader 的构造器
public XmlReader()
{
this._xmlPath = string.Empty;
this._listBox = null;
this.xmlTxtRd = null;
}
/// ＜summary＞
/// 构造器
/// ＜/summary＞
/// ＜param name="_xmlPath"＞xml文件绝对路径＜/param＞
/// ＜param name="_listBox"＞列表框用于显示xml＜/param＞
public XmlReader(string _xmlPath, ListBox _listBox)
{
this._xmlPath = _xmlPath;
this._listBox = _listBox;
this.xmlTxtRd = null;
}
#endregion
#region XmlReader 的资源释放方法
/// ＜summary＞
/// 清理该对象所有正在使用的资源
/// ＜/summary＞
public void Dispose()
{
this.Dispose(true);
GC.SuppressFinalize(this);
}
/// ＜summary＞
/// 释放该对象的实例变量
/// ＜/summary＞
/// ＜param name="disposing"＞＜/param＞
protected virtual void Dispose(bool disposing)
{
if (!disposing)
return;
if (this.xmlTxtRd != null)
{
this.xmlTxtRd.Close();
this.xmlTxtRd = null;
}
if (this._xmlPath != null)
{
this._xmlPath = null;
}
}
#endregion
#region XmlReader 的属性
/// ＜summary＞
/// 获取或设置列表框用于显示xml
/// ＜/summary＞
public ListBox listBox
{
get
{
return this._listBox;
}
set
{
this._listBox = value;
}
}
/// ＜summary＞
/// 获取或设置xml文件的绝对路径
/// ＜/summary＞
public string xmlPath
{
get
{
return this._xmlPath;
}
set
{
this._xmlPath = value;
}
}
#endregion
/// ＜summary＞
/// 遍历Xml文件
/// ＜/summary＞
public void EachXml()
{
this._listBox.Items.Clear();
this.xmlTxtRd = new XmlTextReader(this._xmlPath);
try
{
while (xmlTxtRd.Read())
{
this._listBox.Items.Add(this.xmlTxtRd.Value);
}
}
catch (XmlException exp)
{
throw new XmlException(_errMsg + this._xmlPath + exp.ToString());
}
finally
{
if (this.xmlTxtRd != null)
this.xmlTxtRd.Close();
}
}
/// ＜summary＞
/// 读取Xml文件的节点类型
/// ＜/summary＞
public void ReadXmlByNodeType()
{
this._listBox.Items.Clear();
this.xmlTxtRd = new XmlTextReader(this._xmlPath);
try
{
while (xmlTxtRd.Read())
{
this._listBox.Items.Add(this.xmlTxtRd.NodeType.ToString());
}
}
catch (XmlException exp)
{
throw new XmlException(_errMsg + this._xmlPath + exp.ToString());
}
finally
{
if (this.xmlTxtRd != null)
this.xmlTxtRd.Close();
}
}
/// ＜summary＞
/// 根据节点类型过滤Xml文档
/// ＜/summary＞
/// ＜param name="xmlNType"＞XmlNodeType 节点类型的数组＜/param＞
public void FilterByNodeType(XmlNodeType[] xmlNType)
{
this._listBox.Items.Clear();
this.xmlTxtRd = new XmlTextReader(this._xmlPath);
try
{
while (xmlTxtRd.Read())
{
for (int i = 0; i < xmlNType.Length; i++)
{
if (xmlTxtRd.NodeType == xmlNType[i])
{
this._listBox.Items.Add(xmlTxtRd.Name + " is Type " + xmlTxtRd.NodeType.ToString());
}
}
}
}
catch (XmlException exp)
{
throw new XmlException(_errMsg + this.xmlPath + exp.ToString());
}
finally
{
if (this.xmlTxtRd != null)
this.xmlTxtRd.Close();
}
}
/// ＜summary＞
/// 读取Xml文件的所有文本节点值
/// ＜/summary＞
public void ReadXmlTextValue()
{
this._listBox.Items.Clear();
this.xmlTxtRd = new XmlTextReader(this._xmlPath);
try
{
while (xmlTxtRd.Read())
{
if (xmlTxtRd.NodeType == XmlNodeType.Text)
{
this._listBox.Items.Add(xmlTxtRd.Value);
}
}
}
catch (XmlException xmlExp)
{
throw new XmlException(_errMsg + this._xmlPath + xmlExp.ToString());
}
finally
{
if (this.xmlTxtRd != null)
this.xmlTxtRd.Close();
}
}
/// ＜summary＞
/// 读取Xml文件的属性
/// ＜/summary＞
public void ReadXmlAttributes()
{
this._listBox.Items.Clear();
this.xmlTxtRd = new XmlTextReader(this._xmlPath);
try
{
while (xmlTxtRd.Read())
{
if (xmlTxtRd.NodeType == XmlNodeType.Element)
{
if (xmlTxtRd.HasAttributes)
{
this._listBox.Items.Add("The Element " + xmlTxtRd.Name + " has " + xmlTxtRd.AttributeCount + " Attributes");
this._listBox.Items.Add("The Attributes are:");
while (xmlTxtRd.MoveToNextAttribute())
{
this._listBox.Items.Add(xmlTxtRd.Name + " = " + xmlTxtRd.Value);
}
}
else
{
this._listBox.Items.Add("The Element " + xmlTxtRd.Name + " has no Attribute");
}
this._listBox.Items.Add("");
}
}
}
catch (XmlException xmlExp)
{
throw new XmlException(_errMsg + this._xmlPath + xmlExp.ToString());
}
finally
{
if (this.xmlTxtRd != null)
this.xmlTxtRd.Close();
}
}
/// ＜summary＞
/// 读取Xml文件的命名空间
/// ＜/summary＞
public void ReadXmlNamespace()
{
this._listBox.Items.Clear();
this.xmlTxtRd = new XmlTextReader(this._xmlPath);
try
{
while (xmlTxtRd.Read())
{
if (xmlTxtRd.NodeType == XmlNodeType.Element && xmlTxtRd.Prefix != "")
{
this._listBox.Items.Add("The Prefix " + xmlTxtRd.Prefix + " is associated with namespace " + xmlTxtRd.NamespaceURI);
this._listBox.Items.Add("The Element with the local name " + xmlTxtRd.LocalName + " is associated with" + " the namespace " + xmlTxtRd.NamespaceURI);
}
if (xmlTxtRd.NodeType == XmlNodeType.Element && xmlTxtRd.HasAttributes)
{
while (xmlTxtRd.MoveToNextAttribute())
{
if (xmlTxtRd.Prefix != "")
{
this._listBox.Items.Add("The Prefix " + xmlTxtRd.Prefix + " is associated with namespace " + xmlTxtRd.NamespaceURI);
this._listBox.Items.Add("The Attribute with the local name " + xmlTxtRd.LocalName + " is associated with the namespace " + xmlTxtRd.NamespaceURI);
}
}
}
}
}
catch (XmlException xmlExp)
{
throw new XmlException(_errMsg + this._xmlPath + xmlExp.ToString());
}
finally
{
if (this.xmlTxtRd != null)
this.xmlTxtRd.Close();
}
}
/// ＜summary＞
/// 读取整个Xml文件
/// ＜/summary＞
public void ReadXml()
{
string attAndEle = string.Empty;
this._listBox.Items.Clear();
this.xmlTxtRd = new XmlTextReader(this._xmlPath);
try
{
while (xmlTxtRd.Read())
{
if (xmlTxtRd.NodeType == XmlNodeType.XmlDeclaration)
this._listBox.Items.Add(string.Format("＜?{0} {1} ?＞", xmlTxtRd.Name, xmlTxtRd.Value));
else if (xmlTxtRd.NodeType == XmlNodeType.Element)
{
attAndEle = string.Format("＜{0} ", xmlTxtRd.Name);
if (xmlTxtRd.HasAttributes)
{
while (xmlTxtRd.MoveToNextAttribute())
{
attAndEle = attAndEle + string.Format("{0}=\"{1}\" ", xmlTxtRd.Name, xmlTxtRd.Value);
}
}
attAndEle = attAndEle.Trim() + "＞";
this._listBox.Items.Add(attAndEle);
}
else if (xmlTxtRd.NodeType == XmlNodeType.EndElement)
this._listBox.Items.Add(string.Format("＜/{0}＞", xmlTxtRd.Name));
else if (xmlTxtRd.NodeType == XmlNodeType.Text)
this._listBox.Items.Add(xmlTxtRd.Value);
}
}
catch (XmlException xmlExp)
{
throw new XmlException(_errMsg + this._xmlPath + xmlExp.ToString());
}
finally
{
if (this.xmlTxtRd != null)
this.xmlTxtRd.Close();
}
}
}
}
[/code]
窗体代码如下：
[code]
csharp
namespace XMLReading
{
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
using System.Xml;
public class Form1 : System.Windows.Forms.Form
{
private System.Windows.Forms.ListBox listBox1;
private System.Windows.Forms.Button button1;
private System.Windows.Forms.Button button2;
private System.Windows.Forms.Button button3;
private System.Windows.Forms.Button button4;
private System.Windows.Forms.Button button5;
private System.Windows.Forms.Button button6;
private System.Windows.Forms.Button button7;
private string xmlPath;
private XmlReader xRead;
/// ＜summary＞
/// 必需的设计器变量。
/// ＜/summary＞
private System.ComponentModel.Container components = null;
public Form1()
{
InitializeComponent();
}
/// ＜summary＞
/// 清理所有正在使用的资源。
/// ＜/summary＞
protected override void Dispose(bool disposing)
{
if (disposing)
{
if (components != null)
{
components.Dispose();
}
}
base.Dispose(disposing);
}
#region Windows 窗体设计器生成的代码
/// ＜summary＞
/// 设计器支持所需的方法 - 不要使用代码编辑器修改
/// 此方法的内容。
/// ＜/summary＞
private void InitializeComponent()
{
this.listBox1 = new System.Windows.Forms.ListBox();
this.button1 = new System.Windows.Forms.Button();
this.button2 = new System.Windows.Forms.Button();
this.button3 = new System.Windows.Forms.Button();
this.button4 = new System.Windows.Forms.Button();
this.button5 = new System.Windows.Forms.Button();
this.button6 = new System.Windows.Forms.Button();
this.button7 = new System.Windows.Forms.Button();
this.SuspendLayout();
//
// listBox1
//
this.listBox1.Anchor = ((System.Windows.Forms.AnchorStyles)((((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Bottom)
| System.Windows.Forms.AnchorStyles.Left)
| System.Windows.Forms.AnchorStyles.Right)));
this.listBox1.ItemHeight = 12;
this.listBox1.Location = new System.Drawing.Point(8, 8);
this.listBox1.Name = "listBox1";
this.listBox1.Size = new System.Drawing.Size(716, 460);
this.listBox1.TabIndex = 0;
//
// button1
//
this.button1.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Left)));
this.button1.Location = new System.Drawing.Point(8, 488);
this.button1.Name = "button1";
this.button1.TabIndex = 1;
this.button1.Text = "Example1";
this.button1.Click += new System.EventHandler(this.button1_Click);
//
// button2
//
this.button2.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Left)));
this.button2.Location = new System.Drawing.Point(96, 488);
this.button2.Name = "button2";
this.button2.TabIndex = 2;
this.button2.Text = "Example2";
this.button2.Click += new System.EventHandler(this.button2_Click);
//
// button3
//
this.button3.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Right)));
this.button3.Location = new System.Drawing.Point(648, 488);
this.button3.Name = "button3";
this.button3.TabIndex = 3;
this.button3.Text = "Example7";
this.button3.Click += new System.EventHandler(this.button3_Click);
//
// button4
//
this.button4.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Left)));
this.button4.Location = new System.Drawing.Point(184, 488);
this.button4.Name = "button4";
this.button4.TabIndex = 4;
this.button4.Text = "Example3";
this.button4.Click += new System.EventHandler(this.button4_Click);
//
// button5
//
this.button5.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Left)));
this.button5.Location = new System.Drawing.Point(272, 488);
this.button5.Name = "button5";
this.button5.TabIndex = 5;
this.button5.Text = "Example4";
this.button5.Click += new System.EventHandler(this.button5_Click);
//
// button6
//
this.button6.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Left)));
this.button6.Location = new System.Drawing.Point(360, 488);
this.button6.Name = "button6";
this.button6.TabIndex = 6;
this.button6.Text = "Example5";
this.button6.Click += new System.EventHandler(this.button6_Click);
//
// button7
//
this.button7.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Left)));
this.button7.Location = new System.Drawing.Point(448, 488);
this.button7.Name = "button7";
this.button7.TabIndex = 7;
this.button7.Text = "Example6";
this.button7.Click += new System.EventHandler(this.button7_Click);
//
// Form1
//
this.AutoScaleBaseSize = new System.Drawing.Size(6, 14);
this.ClientSize = new System.Drawing.Size(728, 517);
this.Controls.Add(this.button7);
this.Controls.Add(this.button6);
this.Controls.Add(this.button5);
this.Controls.Add(this.button4);
this.Controls.Add(this.button3);
this.Controls.Add(this.button2);
this.Controls.Add(this.button1);
this.Controls.Add(this.listBox1);
this.Name = "Form1";
this.Text = "XMLReader";
this.ResumeLayout(false);
//
// xmlPath
//
this.xmlPath = "sample.xml";
}
#endregion
/// ＜summary＞
/// 应用程序的主入口点。
/// ＜/summary＞
[STAThread]
static void Main()
{
Application.Run(new Form1());
}
private void button1_Click(object sender, System.EventArgs e)
{
xRead = new XmlReader(this.xmlPath, this.listBox1);
try
{
xRead.EachXml();
}
catch (XmlException xmlExp)
{
MessageBox.Show(xmlExp.ToString(), "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
catch (Exception exp)
{
MessageBox.Show(exp.ToString(), "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
finally
{
xRead.Dispose();
}
}
private void button2_Click(object sender, System.EventArgs e)
{
xRead = new XmlReader(this.xmlPath, this.listBox1);
try
{
xRead.ReadXmlByNodeType();
}
catch (XmlException xmlExp)
{
MessageBox.Show(xmlExp.ToString(), "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
catch (Exception exp)
{
MessageBox.Show(exp.ToString(), "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
finally
{
xRead.Dispose();
}
}
private void button3_Click(object sender, System.EventArgs e)
{
XmlNodeType[] xmlNType = { XmlNodeType.Element, XmlNodeType.EndElement, XmlNodeType.XmlDeclaration };
xRead = new XmlReader(this.xmlPath, this.listBox1);
try
{
xRead.FilterByNodeType(xmlNType);
}
catch (XmlException xmlExp)
{
MessageBox.Show(xmlExp.ToString(), "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
catch (Exception exp)
{
MessageBox.Show(exp.ToString(), "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
finally
{
xRead.Dispose();
}
}
private void button4_Click(object sender, System.EventArgs e)
{
xRead = new XmlReader(this.xmlPath, this.listBox1);
try
{
xRead.ReadXmlTextValue();
}
catch (XmlException xmlExp)
{
MessageBox.Show(xmlExp.ToString(), "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
catch (Exception exp)
{
MessageBox.Show(exp.ToString(), "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
finally
{
xRead.Dispose();
}
}
private void button5_Click(object sender, System.EventArgs e)
{
xRead = new XmlReader(this.xmlPath, this.listBox1);
try
{
xRead.ReadXmlAttributes();
}
catch (XmlException xmlExp)
{
MessageBox.Show(xmlExp.ToString(), "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
catch (Exception exp)
{
MessageBox.Show(exp.ToString(), "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
finally
{
xRead.Dispose();
}
}
private void button6_Click(object sender, System.EventArgs e)
{
xRead = new XmlReader(this.xmlPath, this.listBox1);
try
{
xRead.ReadXmlNamespace();
}
catch (XmlException xmlExp)
{
MessageBox.Show(xmlExp.ToString(), "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
catch (Exception exp)
{
MessageBox.Show(exp.ToString(), "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
finally
{
xRead.Dispose();
}
}
private void button7_Click(object sender, System.EventArgs e)
{
xRead = new XmlReader(this.xmlPath, this.listBox1);
try
{
xRead.ReadXml();
}
catch (XmlException xmlExp)
{
MessageBox.Show(xmlExp.ToString(), "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
catch (Exception exp)
{
MessageBox.Show(exp.ToString(), "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
finally
{
xRead.Dispose();
}
}
}
}
[/code]
以下是用于测试的XML文件：
在项目中新建一个XML文件取名为sample.xml，建好后把该文件拷到项目的bin目录下的Debug目录下
＜?xml version="1.0" encoding="utf-8" ?＞
＜Invoices date="28/11/2001" xmlns:cat="uri:Business-Categories"＞
＜customers custname="Chile Wines Inc" phone="1241 923 56332" email="[email protected]" custid="192398" delivery="international" offerID="27"＞
＜cat:businfo＞Wine Division South＜/cat:businfo＞
＜cat:businfo＞Beer Division North＜/cat:businfo＞
＜order orderID="OID921" batchid="123"＞
＜details＞
＜items cat:num="2"＞
＜item＞Rancagua While＜/item＞
＜item＞Rancagua Red＜/item＞
＜/items＞
＜/details＞
＜/order＞
＜order orderID="OID927"＞
＜details＞
＜items num="5"＞
＜item＞Chillan Red＜/item＞
＜item＞Rancagua While＜/item＞
＜item＞Santiago Red＜/item＞
＜item＞Rancagua While＜/item＞
＜item＞Rancagua Red＜/item＞
＜/items＞
＜/details＞
＜/order＞
＜order orderID="OID931" batchid="123"＞
＜details＞
＜items num="6"＞
＜item＞Rancegao Red＜/item＞
＜item＞Sutothad Black＜/item＞
＜item＞BlackNme Blue＜/item＞
＜item＞Booklist Red＜/item＞
＜item＞Rancegao White＜/item＞
＜/items＞
＜/details＞
＜/order＞
＜/customers＞
＜/Invoices＞
|
__label__pos
| 0.997849 |
I ran into an example where recipetool was getting the name/version
completely wrong:
https://bitbucket.org/sortsmill/libunicodenames/downloads/libunicodenames-1.1.0_beta1.tar.xz
>From this it would create a libunicodenames-1.1.0-beta1_1.1.0-beta1.bb
file (likely because it couldn't split the file name and therefore took
all of it, then got the version from one of the files inside the
tarball). When this happens it's just irritating because you then have
to delete the recipe / run devtool reset and then run recipetool create
/ devtool add again and specify the version manually.
This patch is the result of systematically running the
determine_from_filename() function over the files on the Yocto Project
source mirror and my local downloads directory and fixing as many of the
generic issues as reasonably practical - it now gets the name and
version correct much more often. There are still cases where it won't,
but they are now in the minority.
Signed-off-by: Paul Eggleton <[email protected]>
---
scripts/lib/recipetool/create.py | 50 +++++++++++++++++++++++++++++-----------
1 file changed, 36 insertions(+), 14 deletions(-)
diff --git a/scripts/lib/recipetool/create.py b/scripts/lib/recipetool/create.py
index cd86747..f7b0676 100644
--- a/scripts/lib/recipetool/create.py
+++ b/scripts/lib/recipetool/create.py
@@ -256,27 +256,49 @@ def validate_pv(pv):
def determine_from_filename(srcfile):
"""Determine name and version from a filename"""
- part = ''
- if '.tar.' in srcfile:
- namepart = srcfile.split('.tar.')[0].lower()
- else:
- namepart = os.path.splitext(srcfile)[0].lower()
if is_package(srcfile):
# Force getting the value from the package metadata
return None, None
+
+ if '.tar.' in srcfile:
+ namepart = srcfile.split('.tar.')[0]
else:
- splitval = namepart.rsplit('_', 1)
+ namepart = os.path.splitext(srcfile)[0]
+ namepart = namepart.lower().replace('_', '-')
+ if namepart.endswith('.src'):
+ namepart = namepart[:-4]
+ if namepart.endswith('.orig'):
+ namepart = namepart[:-5]
+ splitval = namepart.split('-')
+ logger.debug('determine_from_filename: split name %s into: %s' % (srcfile,
splitval))
+
+ ver_re = re.compile('^v?[0-9]')
+
+ pv = None
+ pn = None
if len(splitval) == 1:
- splitval = namepart.rsplit('-', 1)
- pn = splitval[0].replace('_', '-')
- if len(splitval) > 1:
- if splitval[1][0] in '0123456789':
- pv = splitval[1]
+ # Try to split the version out if there is no separator (or a .)
+ res = re.match('^([^0-9]+)([0-9.]+.*)$', namepart)
+ if res:
+ if len(res.group(1)) > 1 and len(res.group(2)) > 1:
+ pn = res.group(1).rstrip('.')
+ pv = res.group(2)
else:
- pn = '-'.join(splitval).replace('_', '-')
- pv = None
+ pn = namepart
else:
- pv = None
+ if splitval[-1] in ['source', 'src']:
+ splitval.pop()
+ if len(splitval) > 2 and
re.match('^(alpha|beta|stable|release|rc[0-9]|pre[0-9]|p[0-9]|[0-9]{8})',
splitval[-1]) and ver_re.match(splitval[-2]):
+ pv = '-'.join(splitval[-2:])
+ if pv.endswith('-release'):
+ pv = pv[:-8]
+ splitval = splitval[:-2]
+ elif ver_re.match(splitval[-1]):
+ pv = splitval.pop()
+ pn = '-'.join(splitval)
+ if pv and pv.startswith('v'):
+ pv = pv[1:]
+ logger.debug('determine_from_filename: name = "%s" version = "%s"' % (pn,
pv))
return (pn, pv)
def determine_from_url(srcuri):
--
2.5.5
--
_______________________________________________
Openembedded-core mailing list
[email protected]
http://lists.openembedded.org/mailman/listinfo/openembedded-core
Reply via email to
|
__label__pos
| 0.937577 |
ia64/xen-unstable
view xen/common/sched_sedf.c @ 10570:8dc4af3f192c
[IA64] Implement and use DOM0_DOMAIN_STEUP.
DOM0_GETMEMLIST now reads ptes and use gpfn.
Domain builder reworked: calls DOMAIN_SETUP, setup start_info page.
SAL data are now in domain memory.
is_vti field added in domain.arch.
Many cleanups (indentation, static, warnings).
Signed-off-by: Tristan Gingold <[email protected]>
author [email protected]
date Wed Jul 05 09:28:32 2006 -0600 (2006-07-05)
parents ef8cdd1dc836
children 462d6e4cb29a
line source
1 /******************************************************************************
2 * Simple EDF scheduler for xen
3 *
4 * by Stephan Diestelhorst (C) 2004 Cambridge University
5 * based on code by Mark Williamson (C) 2004 Intel Research Cambridge
6 */
8 #include <xen/lib.h>
9 #include <xen/sched.h>
10 #include <xen/sched-if.h>
11 #include <public/sched_ctl.h>
12 #include <xen/timer.h>
13 #include <xen/softirq.h>
14 #include <xen/time.h>
16 /*verbosity settings*/
17 #define SEDFLEVEL 0
18 #define PRINT(_f, _a...) \
19 do { \
20 if ( (_f) <= SEDFLEVEL ) \
21 printk(_a ); \
22 } while ( 0 )
24 #ifndef NDEBUG
25 #define SEDF_STATS
26 #define CHECK(_p) \
27 do { \
28 if ( !(_p) ) \
29 printk("Check '%s' failed, line %d, file %s\n", \
30 #_p , __LINE__, __FILE__); \
31 } while ( 0 )
32 #else
33 #define CHECK(_p) ((void)0)
34 #endif
36 #define EXTRA_NONE (0)
37 #define EXTRA_AWARE (1)
38 #define EXTRA_RUN_PEN (2)
39 #define EXTRA_RUN_UTIL (4)
40 #define EXTRA_WANT_PEN_Q (8)
41 #define EXTRA_PEN_Q (0)
42 #define EXTRA_UTIL_Q (1)
43 #define SEDF_ASLEEP (16)
45 #define EXTRA_QUANTUM (MICROSECS(500))
46 #define WEIGHT_PERIOD (MILLISECS(100))
47 #define WEIGHT_SAFETY (MILLISECS(5))
49 #define PERIOD_MAX MILLISECS(10000) /* 10s */
50 #define PERIOD_MIN (MICROSECS(10)) /* 10us */
51 #define SLICE_MIN (MICROSECS(5)) /* 5us */
53 #define IMPLY(a, b) (!(a) || (b))
54 #define EQ(a, b) ((!!(a)) == (!!(b)))
57 struct sedf_dom_info {
58 struct domain *domain;
59 };
61 struct sedf_vcpu_info {
62 struct vcpu *vcpu;
63 struct list_head list;
64 struct list_head extralist[2];
66 /*Parameters for EDF*/
67 s_time_t period; /*=(relative deadline)*/
68 s_time_t slice; /*=worst case execution time*/
70 /*Advaced Parameters*/
71 /*Latency Scaling*/
72 s_time_t period_orig;
73 s_time_t slice_orig;
74 s_time_t latency;
76 /*status of domain*/
77 int status;
78 /*weights for "Scheduling for beginners/ lazy/ etc." ;)*/
79 short weight;
80 short extraweight;
81 /*Bookkeeping*/
82 s_time_t deadl_abs;
83 s_time_t sched_start_abs;
84 s_time_t cputime;
85 /* times the domain un-/blocked */
86 s_time_t block_abs;
87 s_time_t unblock_abs;
89 /*scores for {util, block penalty}-weighted extratime distribution*/
90 int score[2];
91 s_time_t short_block_lost_tot;
93 /*Statistics*/
94 s_time_t extra_time_tot;
96 #ifdef SEDF_STATS
97 s_time_t block_time_tot;
98 s_time_t penalty_time_tot;
99 int block_tot;
100 int short_block_tot;
101 int long_block_tot;
102 int short_cont;
103 int pen_extra_blocks;
104 int pen_extra_slices;
105 #endif
106 };
108 struct sedf_cpu_info {
109 struct list_head runnableq;
110 struct list_head waitq;
111 struct list_head extraq[2];
112 s_time_t current_slice_expires;
113 };
115 #define EDOM_INFO(d) ((struct sedf_vcpu_info *)((d)->sched_priv))
116 #define CPU_INFO(cpu) ((struct sedf_cpu_info *)schedule_data[cpu].sched_priv)
117 #define LIST(d) (&EDOM_INFO(d)->list)
118 #define EXTRALIST(d,i) (&(EDOM_INFO(d)->extralist[i]))
119 #define RUNQ(cpu) (&CPU_INFO(cpu)->runnableq)
120 #define WAITQ(cpu) (&CPU_INFO(cpu)->waitq)
121 #define EXTRAQ(cpu,i) (&(CPU_INFO(cpu)->extraq[i]))
122 #define IDLETASK(cpu) ((struct vcpu *)schedule_data[cpu].idle)
124 #define PERIOD_BEGIN(inf) ((inf)->deadl_abs - (inf)->period)
126 #define MIN(x,y) (((x)<(y))?(x):(y))
127 #define DIV_UP(x,y) (((x) + (y) - 1) / y)
129 #define extra_runs(inf) ((inf->status) & 6)
130 #define extra_get_cur_q(inf) (((inf->status & 6) >> 1)-1)
131 #define sedf_runnable(edom) (!(EDOM_INFO(edom)->status & SEDF_ASLEEP))
134 static void sedf_dump_cpu_state(int i);
136 static inline int extraq_on(struct vcpu *d, int i)
137 {
138 return ((EXTRALIST(d,i)->next != NULL) &&
139 (EXTRALIST(d,i)->next != EXTRALIST(d,i)));
140 }
142 static inline void extraq_add_head(struct vcpu *d, int i)
143 {
144 list_add(EXTRALIST(d,i), EXTRAQ(d->processor,i));
145 ASSERT(extraq_on(d, i));
146 }
148 static inline void extraq_add_tail(struct vcpu *d, int i)
149 {
150 list_add_tail(EXTRALIST(d,i), EXTRAQ(d->processor,i));
151 ASSERT(extraq_on(d, i));
152 }
154 static inline void extraq_del(struct vcpu *d, int i)
155 {
156 struct list_head *list = EXTRALIST(d,i);
157 ASSERT(extraq_on(d,i));
158 PRINT(3, "Removing domain %i.%i from L%i extraq\n",
159 d->domain->domain_id, d->vcpu_id, i);
160 list_del(list);
161 list->next = NULL;
162 ASSERT(!extraq_on(d, i));
163 }
165 /* adds a domain to the queue of processes which are aware of extra time. List
166 is sorted by score, where a lower score means higher priority for an extra
167 slice. It also updates the score, by simply subtracting a fixed value from
168 each entry, in order to avoid overflow. The algorithm works by simply
169 charging each domain that recieved extratime with an inverse of its weight.
170 */
171 static inline void extraq_add_sort_update(struct vcpu *d, int i, int sub)
172 {
173 struct list_head *cur;
174 struct sedf_vcpu_info *curinf;
176 ASSERT(!extraq_on(d,i));
178 PRINT(3, "Adding domain %i.%i (score= %i, short_pen= %"PRIi64")"
179 " to L%i extraq\n",
180 d->domain->domain_id, d->vcpu_id, EDOM_INFO(d)->score[i],
181 EDOM_INFO(d)->short_block_lost_tot, i);
183 /*
184 * Iterate through all elements to find our "hole" and on our way
185 * update all the other scores.
186 */
187 list_for_each ( cur, EXTRAQ(d->processor, i) )
188 {
189 curinf = list_entry(cur,struct sedf_vcpu_info,extralist[i]);
190 curinf->score[i] -= sub;
191 if ( EDOM_INFO(d)->score[i] < curinf->score[i] )
192 break;
193 PRINT(4,"\tbehind domain %i.%i (score= %i)\n",
194 curinf->vcpu->domain->domain_id,
195 curinf->vcpu->vcpu_id, curinf->score[i]);
196 }
198 /* cur now contains the element, before which we'll enqueue. */
199 PRINT(3, "\tlist_add to %p\n", cur->prev);
200 list_add(EXTRALIST(d,i),cur->prev);
202 /* Continue updating the extraq. */
203 if ( (cur != EXTRAQ(d->processor,i)) && sub )
204 {
205 for ( cur = cur->next; cur != EXTRAQ(d->processor,i); cur = cur->next )
206 {
207 curinf = list_entry(cur,struct sedf_vcpu_info, extralist[i]);
208 curinf->score[i] -= sub;
209 PRINT(4, "\tupdating domain %i.%i (score= %u)\n",
210 curinf->vcpu->domain->domain_id,
211 curinf->vcpu->vcpu_id, curinf->score[i]);
212 }
213 }
215 ASSERT(extraq_on(d,i));
216 }
217 static inline void extraq_check(struct vcpu *d)
218 {
219 if ( extraq_on(d, EXTRA_UTIL_Q) )
220 {
221 PRINT(2,"Dom %i.%i is on L1 extraQ\n",
222 d->domain->domain_id, d->vcpu_id);
224 if ( !(EDOM_INFO(d)->status & EXTRA_AWARE) &&
225 !extra_runs(EDOM_INFO(d)) )
226 {
227 extraq_del(d, EXTRA_UTIL_Q);
228 PRINT(2,"Removed dom %i.%i from L1 extraQ\n",
229 d->domain->domain_id, d->vcpu_id);
230 }
231 }
232 else
233 {
234 PRINT(2, "Dom %i.%i is NOT on L1 extraQ\n",
235 d->domain->domain_id,
236 d->vcpu_id);
238 if ( (EDOM_INFO(d)->status & EXTRA_AWARE) && sedf_runnable(d) )
239 {
240 extraq_add_sort_update(d, EXTRA_UTIL_Q, 0);
241 PRINT(2,"Added dom %i.%i to L1 extraQ\n",
242 d->domain->domain_id, d->vcpu_id);
243 }
244 }
245 }
247 static inline void extraq_check_add_unblocked(struct vcpu *d, int priority)
248 {
249 struct sedf_vcpu_info *inf = EDOM_INFO(d);
251 if ( inf->status & EXTRA_AWARE )
252 /* Put on the weighted extraq without updating any scores. */
253 extraq_add_sort_update(d, EXTRA_UTIL_Q, 0);
254 }
256 static inline int __task_on_queue(struct vcpu *d)
257 {
258 return (((LIST(d))->next != NULL) && (LIST(d)->next != LIST(d)));
259 }
261 static inline void __del_from_queue(struct vcpu *d)
262 {
263 struct list_head *list = LIST(d);
264 ASSERT(__task_on_queue(d));
265 PRINT(3,"Removing domain %i.%i (bop= %"PRIu64") from runq/waitq\n",
266 d->domain->domain_id, d->vcpu_id, PERIOD_BEGIN(EDOM_INFO(d)));
267 list_del(list);
268 list->next = NULL;
269 ASSERT(!__task_on_queue(d));
270 }
272 typedef int(*list_comparer)(struct list_head* el1, struct list_head* el2);
274 static inline void list_insert_sort(
275 struct list_head *list, struct list_head *element, list_comparer comp)
276 {
277 struct list_head *cur;
279 /* Iterate through all elements to find our "hole". */
280 list_for_each( cur, list )
281 if ( comp(element, cur) < 0 )
282 break;
284 /* cur now contains the element, before which we'll enqueue. */
285 PRINT(3,"\tlist_add to %p\n",cur->prev);
286 list_add(element, cur->prev);
287 }
289 #define DOMAIN_COMPARER(name, field, comp1, comp2) \
290 int name##_comp(struct list_head* el1, struct list_head* el2) \
291 { \
292 struct sedf_vcpu_info *d1, *d2; \
293 d1 = list_entry(el1,struct sedf_vcpu_info, field); \
294 d2 = list_entry(el2,struct sedf_vcpu_info, field); \
295 if ( (comp1) == (comp2) ) \
296 return 0; \
297 if ( (comp1) < (comp2) ) \
298 return -1; \
299 else \
300 return 1; \
301 }
303 /* adds a domain to the queue of processes which wait for the beginning of the
304 next period; this list is therefore sortet by this time, which is simply
305 absol. deadline - period
306 */
307 DOMAIN_COMPARER(waitq, list, PERIOD_BEGIN(d1), PERIOD_BEGIN(d2));
308 static inline void __add_to_waitqueue_sort(struct vcpu *v)
309 {
310 ASSERT(!__task_on_queue(v));
311 PRINT(3,"Adding domain %i.%i (bop= %"PRIu64") to waitq\n",
312 v->domain->domain_id, v->vcpu_id, PERIOD_BEGIN(EDOM_INFO(v)));
313 list_insert_sort(WAITQ(v->processor), LIST(v), waitq_comp);
314 ASSERT(__task_on_queue(v));
315 }
317 /* adds a domain to the queue of processes which have started their current
318 period and are runnable (i.e. not blocked, dieing,...). The first element
319 on this list is running on the processor, if the list is empty the idle
320 task will run. As we are implementing EDF, this list is sorted by deadlines.
321 */
322 DOMAIN_COMPARER(runq, list, d1->deadl_abs, d2->deadl_abs);
323 static inline void __add_to_runqueue_sort(struct vcpu *v)
324 {
325 PRINT(3,"Adding domain %i.%i (deadl= %"PRIu64") to runq\n",
326 v->domain->domain_id, v->vcpu_id, EDOM_INFO(v)->deadl_abs);
327 list_insert_sort(RUNQ(v->processor), LIST(v), runq_comp);
328 }
331 static int sedf_init_vcpu(struct vcpu *v)
332 {
333 struct sedf_vcpu_info *inf;
335 if ( v->domain->sched_priv == NULL )
336 {
337 v->domain->sched_priv = xmalloc(struct sedf_dom_info);
338 if ( v->domain->sched_priv == NULL )
339 return -1;
340 memset(v->domain->sched_priv, 0, sizeof(struct sedf_dom_info));
341 }
343 if ( (v->sched_priv = xmalloc(struct sedf_vcpu_info)) == NULL )
344 return -1;
345 memset(v->sched_priv, 0, sizeof(struct sedf_vcpu_info));
347 inf = EDOM_INFO(v);
348 inf->vcpu = v;
350 /* Allocate per-CPU context if this is the first domain to be added. */
351 if ( unlikely(schedule_data[v->processor].sched_priv == NULL) )
352 {
353 schedule_data[v->processor].sched_priv =
354 xmalloc(struct sedf_cpu_info);
355 BUG_ON(schedule_data[v->processor].sched_priv == NULL);
356 memset(CPU_INFO(v->processor), 0, sizeof(*CPU_INFO(v->processor)));
357 INIT_LIST_HEAD(WAITQ(v->processor));
358 INIT_LIST_HEAD(RUNQ(v->processor));
359 INIT_LIST_HEAD(EXTRAQ(v->processor,EXTRA_PEN_Q));
360 INIT_LIST_HEAD(EXTRAQ(v->processor,EXTRA_UTIL_Q));
361 }
363 /* Every VCPU gets an equal share of extratime by default. */
364 inf->deadl_abs = 0;
365 inf->latency = 0;
366 inf->status = EXTRA_AWARE | SEDF_ASLEEP;
367 inf->extraweight = 1;
369 if ( v->domain->domain_id == 0 )
370 {
371 /* Domain0 gets 75% guaranteed (15ms every 20ms). */
372 inf->period = MILLISECS(20);
373 inf->slice = MILLISECS(15);
374 }
375 else
376 {
377 /* Best-effort extratime only. */
378 inf->period = WEIGHT_PERIOD;
379 inf->slice = 0;
380 }
382 inf->period_orig = inf->period; inf->slice_orig = inf->slice;
383 INIT_LIST_HEAD(&(inf->list));
384 INIT_LIST_HEAD(&(inf->extralist[EXTRA_PEN_Q]));
385 INIT_LIST_HEAD(&(inf->extralist[EXTRA_UTIL_Q]));
387 if ( !is_idle_vcpu(v) )
388 {
389 extraq_check(v);
390 }
391 else
392 {
393 EDOM_INFO(v)->deadl_abs = 0;
394 EDOM_INFO(v)->status &= ~SEDF_ASLEEP;
395 }
397 return 0;
398 }
400 static void sedf_destroy_domain(struct domain *d)
401 {
402 int i;
404 xfree(d->sched_priv);
406 for ( i = 0; i < MAX_VIRT_CPUS; i++ )
407 if ( d->vcpu[i] )
408 xfree(d->vcpu[i]->sched_priv);
409 }
411 /*
412 * Handles the rescheduling & bookkeeping of domains running in their
413 * guaranteed timeslice.
414 */
415 static void desched_edf_dom(s_time_t now, struct vcpu* d)
416 {
417 struct sedf_vcpu_info* inf = EDOM_INFO(d);
419 /* Current domain is running in real time mode. */
420 ASSERT(__task_on_queue(d));
422 /* Update the domain's cputime. */
423 inf->cputime += now - inf->sched_start_abs;
425 /*
426 * Scheduling decisions which don't remove the running domain from the
427 * runq.
428 */
429 if ( (inf->cputime < inf->slice) && sedf_runnable(d) )
430 return;
432 __del_from_queue(d);
434 /*
435 * Manage bookkeeping (i.e. calculate next deadline, memorise
436 * overrun-time of slice) of finished domains.
437 */
438 if ( inf->cputime >= inf->slice )
439 {
440 inf->cputime -= inf->slice;
442 if ( inf->period < inf->period_orig )
443 {
444 /* This domain runs in latency scaling or burst mode. */
445 inf->period *= 2;
446 inf->slice *= 2;
447 if ( (inf->period > inf->period_orig) ||
448 (inf->slice > inf->slice_orig) )
449 {
450 /* Reset slice and period. */
451 inf->period = inf->period_orig;
452 inf->slice = inf->slice_orig;
453 }
454 }
456 /* Set next deadline. */
457 inf->deadl_abs += inf->period;
458 }
460 /* Add a runnable domain to the waitqueue. */
461 if ( sedf_runnable(d) )
462 {
463 __add_to_waitqueue_sort(d);
464 }
465 else
466 {
467 /* We have a blocked realtime task -> remove it from exqs too. */
468 if ( extraq_on(d, EXTRA_PEN_Q) )
469 extraq_del(d, EXTRA_PEN_Q);
470 if ( extraq_on(d, EXTRA_UTIL_Q) )
471 extraq_del(d, EXTRA_UTIL_Q);
472 }
474 ASSERT(EQ(sedf_runnable(d), __task_on_queue(d)));
475 ASSERT(IMPLY(extraq_on(d, EXTRA_UTIL_Q) || extraq_on(d, EXTRA_PEN_Q),
476 sedf_runnable(d)));
477 }
480 /* Update all elements on the queues */
481 static void update_queues(
482 s_time_t now, struct list_head *runq, struct list_head *waitq)
483 {
484 struct list_head *cur, *tmp;
485 struct sedf_vcpu_info *curinf;
487 PRINT(3,"Updating waitq..\n");
489 /*
490 * Check for the first elements of the waitqueue, whether their
491 * next period has already started.
492 */
493 list_for_each_safe ( cur, tmp, waitq )
494 {
495 curinf = list_entry(cur, struct sedf_vcpu_info, list);
496 PRINT(4,"\tLooking @ dom %i.%i\n",
497 curinf->vcpu->domain->domain_id, curinf->vcpu->vcpu_id);
498 if ( PERIOD_BEGIN(curinf) > now )
499 break;
500 __del_from_queue(curinf->vcpu);
501 __add_to_runqueue_sort(curinf->vcpu);
502 }
504 PRINT(3,"Updating runq..\n");
506 /* Process the runq, find domains that are on the runq that shouldn't. */
507 list_for_each_safe ( cur, tmp, runq )
508 {
509 curinf = list_entry(cur,struct sedf_vcpu_info,list);
510 PRINT(4,"\tLooking @ dom %i.%i\n",
511 curinf->vcpu->domain->domain_id, curinf->vcpu->vcpu_id);
513 if ( unlikely(curinf->slice == 0) )
514 {
515 /* Ignore domains with empty slice. */
516 PRINT(4,"\tUpdating zero-slice domain %i.%i\n",
517 curinf->vcpu->domain->domain_id,
518 curinf->vcpu->vcpu_id);
519 __del_from_queue(curinf->vcpu);
521 /* Move them to their next period. */
522 curinf->deadl_abs += curinf->period;
524 /* Ensure that the start of the next period is in the future. */
525 if ( unlikely(PERIOD_BEGIN(curinf) < now) )
526 curinf->deadl_abs +=
527 (DIV_UP(now - PERIOD_BEGIN(curinf),
528 curinf->period)) * curinf->period;
530 /* Put them back into the queue. */
531 __add_to_waitqueue_sort(curinf->vcpu);
532 }
533 else if ( unlikely((curinf->deadl_abs < now) ||
534 (curinf->cputime > curinf->slice)) )
535 {
536 /*
537 * We missed the deadline or the slice was already finished.
538 * Might hapen because of dom_adj.
539 */
540 PRINT(4,"\tDomain %i.%i exceeded it's deadline/"
541 "slice (%"PRIu64" / %"PRIu64") now: %"PRIu64
542 " cputime: %"PRIu64"\n",
543 curinf->vcpu->domain->domain_id,
544 curinf->vcpu->vcpu_id,
545 curinf->deadl_abs, curinf->slice, now,
546 curinf->cputime);
547 __del_from_queue(curinf->vcpu);
549 /* Common case: we miss one period. */
550 curinf->deadl_abs += curinf->period;
552 /*
553 * If we are still behind: modulo arithmetic, force deadline
554 * to be in future and aligned to period borders.
555 */
556 if ( unlikely(curinf->deadl_abs < now) )
557 curinf->deadl_abs +=
558 DIV_UP(now - curinf->deadl_abs,
559 curinf->period) * curinf->period;
560 ASSERT(curinf->deadl_abs >= now);
562 /* Give a fresh slice. */
563 curinf->cputime = 0;
564 if ( PERIOD_BEGIN(curinf) > now )
565 __add_to_waitqueue_sort(curinf->vcpu);
566 else
567 __add_to_runqueue_sort(curinf->vcpu);
568 }
569 else
570 break;
571 }
573 PRINT(3,"done updating the queues\n");
574 }
577 /* removes a domain from the head of the according extraQ and
578 requeues it at a specified position:
579 round-robin extratime: end of extraQ
580 weighted ext.: insert in sorted list by score
581 if the domain is blocked / has regained its short-block-loss
582 time it is not put on any queue */
583 static void desched_extra_dom(s_time_t now, struct vcpu *d)
584 {
585 struct sedf_vcpu_info *inf = EDOM_INFO(d);
586 int i = extra_get_cur_q(inf);
587 unsigned long oldscore;
589 ASSERT(extraq_on(d, i));
591 /* Unset all running flags. */
592 inf->status &= ~(EXTRA_RUN_PEN | EXTRA_RUN_UTIL);
593 /* Fresh slice for the next run. */
594 inf->cputime = 0;
595 /* Accumulate total extratime. */
596 inf->extra_time_tot += now - inf->sched_start_abs;
597 /* Remove extradomain from head of the queue. */
598 extraq_del(d, i);
600 /* Update the score. */
601 oldscore = inf->score[i];
602 if ( i == EXTRA_PEN_Q )
603 {
604 /*domain was running in L0 extraq*/
605 /*reduce block lost, probably more sophistication here!*/
606 /*inf->short_block_lost_tot -= EXTRA_QUANTUM;*/
607 inf->short_block_lost_tot -= now - inf->sched_start_abs;
608 PRINT(3,"Domain %i.%i: Short_block_loss: %"PRIi64"\n",
609 inf->vcpu->domain->domain_id, inf->vcpu->vcpu_id,
610 inf->short_block_lost_tot);
611 #if 0
612 /*
613 * KAF: If we don't exit short-blocking state at this point
614 * domain0 can steal all CPU for up to 10 seconds before
615 * scheduling settles down (when competing against another
616 * CPU-bound domain). Doing this seems to make things behave
617 * nicely. Noone gets starved by default.
618 */
619 if ( inf->short_block_lost_tot <= 0 )
620 #endif
621 {
622 PRINT(4,"Domain %i.%i compensated short block loss!\n",
623 inf->vcpu->domain->domain_id, inf->vcpu->vcpu_id);
624 /*we have (over-)compensated our block penalty*/
625 inf->short_block_lost_tot = 0;
626 /*we don't want a place on the penalty queue anymore!*/
627 inf->status &= ~EXTRA_WANT_PEN_Q;
628 goto check_extra_queues;
629 }
631 /*we have to go again for another try in the block-extraq,
632 the score is not used incremantally here, as this is
633 already done by recalculating the block_lost*/
634 inf->score[EXTRA_PEN_Q] = (inf->period << 10) /
635 inf->short_block_lost_tot;
636 oldscore = 0;
637 }
638 else
639 {
640 /*domain was running in L1 extraq => score is inverse of
641 utilization and is used somewhat incremental!*/
642 if ( !inf->extraweight )
643 /*NB: use fixed point arithmetic with 10 bits*/
644 inf->score[EXTRA_UTIL_Q] = (inf->period << 10) /
645 inf->slice;
646 else
647 /*conversion between realtime utilisation and extrawieght:
648 full (ie 100%) utilization is equivalent to 128 extraweight*/
649 inf->score[EXTRA_UTIL_Q] = (1<<17) / inf->extraweight;
650 }
652 check_extra_queues:
653 /* Adding a runnable domain to the right queue and removing blocked ones*/
654 if ( sedf_runnable(d) )
655 {
656 /*add according to score: weighted round robin*/
657 if (((inf->status & EXTRA_AWARE) && (i == EXTRA_UTIL_Q)) ||
658 ((inf->status & EXTRA_WANT_PEN_Q) && (i == EXTRA_PEN_Q)))
659 extraq_add_sort_update(d, i, oldscore);
660 }
661 else
662 {
663 /*remove this blocked domain from the waitq!*/
664 __del_from_queue(d);
665 /*make sure that we remove a blocked domain from the other
666 extraq too*/
667 if ( i == EXTRA_PEN_Q )
668 {
669 if ( extraq_on(d, EXTRA_UTIL_Q) )
670 extraq_del(d, EXTRA_UTIL_Q);
671 }
672 else
673 {
674 if ( extraq_on(d, EXTRA_PEN_Q) )
675 extraq_del(d, EXTRA_PEN_Q);
676 }
677 }
679 ASSERT(EQ(sedf_runnable(d), __task_on_queue(d)));
680 ASSERT(IMPLY(extraq_on(d, EXTRA_UTIL_Q) || extraq_on(d, EXTRA_PEN_Q),
681 sedf_runnable(d)));
682 }
685 static struct task_slice sedf_do_extra_schedule(
686 s_time_t now, s_time_t end_xt, struct list_head *extraq[], int cpu)
687 {
688 struct task_slice ret;
689 struct sedf_vcpu_info *runinf;
690 ASSERT(end_xt > now);
692 /* Enough time left to use for extratime? */
693 if ( end_xt - now < EXTRA_QUANTUM )
694 goto return_idle;
696 if ( !list_empty(extraq[EXTRA_PEN_Q]) )
697 {
698 /*we still have elements on the level 0 extraq
699 => let those run first!*/
700 runinf = list_entry(extraq[EXTRA_PEN_Q]->next,
701 struct sedf_vcpu_info, extralist[EXTRA_PEN_Q]);
702 runinf->status |= EXTRA_RUN_PEN;
703 ret.task = runinf->vcpu;
704 ret.time = EXTRA_QUANTUM;
705 #ifdef SEDF_STATS
706 runinf->pen_extra_slices++;
707 #endif
708 }
709 else
710 {
711 if ( !list_empty(extraq[EXTRA_UTIL_Q]) )
712 {
713 /*use elements from the normal extraqueue*/
714 runinf = list_entry(extraq[EXTRA_UTIL_Q]->next,
715 struct sedf_vcpu_info,
716 extralist[EXTRA_UTIL_Q]);
717 runinf->status |= EXTRA_RUN_UTIL;
718 ret.task = runinf->vcpu;
719 ret.time = EXTRA_QUANTUM;
720 }
721 else
722 goto return_idle;
723 }
725 ASSERT(ret.time > 0);
726 ASSERT(sedf_runnable(ret.task));
727 return ret;
729 return_idle:
730 ret.task = IDLETASK(cpu);
731 ret.time = end_xt - now;
732 ASSERT(ret.time > 0);
733 ASSERT(sedf_runnable(ret.task));
734 return ret;
735 }
738 /* Main scheduling function
739 Reasons for calling this function are:
740 -timeslice for the current period used up
741 -domain on waitqueue has started it's period
742 -and various others ;) in general: determine which domain to run next*/
743 static struct task_slice sedf_do_schedule(s_time_t now)
744 {
745 int cpu = smp_processor_id();
746 struct list_head *runq = RUNQ(cpu);
747 struct list_head *waitq = WAITQ(cpu);
748 struct sedf_vcpu_info *inf = EDOM_INFO(current);
749 struct list_head *extraq[] = {
750 EXTRAQ(cpu, EXTRA_PEN_Q), EXTRAQ(cpu, EXTRA_UTIL_Q)};
751 struct sedf_vcpu_info *runinf, *waitinf;
752 struct task_slice ret;
754 /*idle tasks don't need any of the following stuf*/
755 if ( is_idle_vcpu(current) )
756 goto check_waitq;
758 /* create local state of the status of the domain, in order to avoid
759 inconsistent state during scheduling decisions, because data for
760 vcpu_runnable is not protected by the scheduling lock!*/
761 if ( !vcpu_runnable(current) )
762 inf->status |= SEDF_ASLEEP;
764 if ( inf->status & SEDF_ASLEEP )
765 inf->block_abs = now;
767 if ( unlikely(extra_runs(inf)) )
768 {
769 /*special treatment of domains running in extra time*/
770 desched_extra_dom(now, current);
771 }
772 else
773 {
774 desched_edf_dom(now, current);
775 }
776 check_waitq:
777 update_queues(now, runq, waitq);
779 /*now simply pick the first domain from the runqueue, which has the
780 earliest deadline, because the list is sorted*/
782 if ( !list_empty(runq) )
783 {
784 runinf = list_entry(runq->next,struct sedf_vcpu_info,list);
785 ret.task = runinf->vcpu;
786 if ( !list_empty(waitq) )
787 {
788 waitinf = list_entry(waitq->next,
789 struct sedf_vcpu_info,list);
790 /*rerun scheduler, when scheduled domain reaches it's
791 end of slice or the first domain from the waitqueue
792 gets ready*/
793 ret.time = MIN(now + runinf->slice - runinf->cputime,
794 PERIOD_BEGIN(waitinf)) - now;
795 }
796 else
797 {
798 ret.time = runinf->slice - runinf->cputime;
799 }
800 CHECK(ret.time > 0);
801 goto sched_done;
802 }
804 if ( !list_empty(waitq) )
805 {
806 waitinf = list_entry(waitq->next,struct sedf_vcpu_info, list);
807 /*we could not find any suitable domain
808 => look for domains that are aware of extratime*/
809 ret = sedf_do_extra_schedule(now, PERIOD_BEGIN(waitinf),
810 extraq, cpu);
811 CHECK(ret.time > 0);
812 }
813 else
814 {
815 /*this could probably never happen, but one never knows...*/
816 /*it can... imagine a second CPU, which is pure scifi ATM,
817 but one never knows ;)*/
818 ret.task = IDLETASK(cpu);
819 ret.time = SECONDS(1);
820 }
822 sched_done:
823 /*TODO: Do something USEFUL when this happens and find out, why it
824 still can happen!!!*/
825 if ( ret.time < 0)
826 {
827 printk("Ouch! We are seriously BEHIND schedule! %"PRIi64"\n",
828 ret.time);
829 ret.time = EXTRA_QUANTUM;
830 }
832 EDOM_INFO(ret.task)->sched_start_abs = now;
833 CHECK(ret.time > 0);
834 ASSERT(sedf_runnable(ret.task));
835 CPU_INFO(cpu)->current_slice_expires = now + ret.time;
836 return ret;
837 }
840 static void sedf_sleep(struct vcpu *d)
841 {
842 PRINT(2,"sedf_sleep was called, domain-id %i.%i\n",
843 d->domain->domain_id, d->vcpu_id);
845 if ( is_idle_vcpu(d) )
846 return;
848 EDOM_INFO(d)->status |= SEDF_ASLEEP;
850 if ( schedule_data[d->processor].curr == d )
851 {
852 cpu_raise_softirq(d->processor, SCHEDULE_SOFTIRQ);
853 }
854 else
855 {
856 if ( __task_on_queue(d) )
857 __del_from_queue(d);
858 if ( extraq_on(d, EXTRA_UTIL_Q) )
859 extraq_del(d, EXTRA_UTIL_Q);
860 if ( extraq_on(d, EXTRA_PEN_Q) )
861 extraq_del(d, EXTRA_PEN_Q);
862 }
863 }
866 /* This function wakes up a domain, i.e. moves them into the waitqueue
867 * things to mention are: admission control is taking place nowhere at
868 * the moment, so we can't be sure, whether it is safe to wake the domain
869 * up at all. Anyway, even if it is safe (total cpu usage <=100%) there are
870 * some considerations on when to allow the domain to wake up and have it's
871 * first deadline...
872 * I detected 3 cases, which could describe the possible behaviour of the
873 * scheduler,
874 * and I'll try to make them more clear:
875 *
876 * 1. Very conservative
877 * -when a blocked domain unblocks, it is allowed to start execution at
878 * the beginning of the next complete period
879 * (D..deadline, R..running, B..blocking/sleeping, U..unblocking/waking up
880 *
881 * DRRB_____D__U_____DRRRRR___D________ ...
882 *
883 * -this causes the domain to miss a period (and a deadlline)
884 * -doesn't disturb the schedule at all
885 * -deadlines keep occuring isochronous
886 *
887 * 2. Conservative Part 1: Short Unblocking
888 * -when a domain unblocks in the same period as it was blocked it
889 * unblocks and may consume the rest of it's original time-slice minus
890 * the time it was blocked
891 * (assume period=9, slice=5)
892 *
893 * DRB_UR___DRRRRR___D...
894 *
895 * -this also doesn't disturb scheduling, but might lead to the fact, that
896 * the domain can't finish it's workload in the period
897 * -in addition to that the domain can be treated prioritised when
898 * extratime is available
899 * -addition: experiments have shown that this may have a HUGE impact on
900 * performance of other domains, becaus it can lead to excessive context
901 * switches
902 *
903 * Part2: Long Unblocking
904 * Part 2a
905 * -it is obvious that such accounting of block time, applied when
906 * unblocking is happening in later periods, works fine aswell
907 * -the domain is treated as if it would have been running since the start
908 * of its new period
909 *
910 * DRB______D___UR___D...
911 *
912 * Part 2b
913 * -if one needs the full slice in the next period, it is necessary to
914 * treat the unblocking time as the start of the new period, i.e. move
915 * the deadline further back (later)
916 * -this doesn't disturb scheduling as well, because for EDF periods can
917 * be treated as minimal inter-release times and scheduling stays
918 * correct, when deadlines are kept relative to the time the process
919 * unblocks
920 *
921 * DRB______D___URRRR___D...<prev [Thread] next>
922 * (D) <- old deadline was here
923 * -problem: deadlines don't occur isochronous anymore
924 * Part 2c (Improved Atropos design)
925 * -when a domain unblocks it is given a very short period (=latency hint)
926 * and slice length scaled accordingly
927 * -both rise again to the original value (e.g. get doubled every period)
928 *
929 * 3. Unconservative (i.e. incorrect)
930 * -to boost the performance of I/O dependent domains it would be possible
931 * to put the domain into the runnable queue immediately, and let it run
932 * for the remainder of the slice of the current period
933 * (or even worse: allocate a new full slice for the domain)
934 * -either behaviour can lead to missed deadlines in other domains as
935 * opposed to approaches 1,2a,2b
936 */
937 static void unblock_short_extra_support(
938 struct sedf_vcpu_info* inf, s_time_t now)
939 {
940 /*this unblocking scheme tries to support the domain, by assigning it
941 a priority in extratime distribution according to the loss of time
942 in this slice due to blocking*/
943 s_time_t pen;
945 /*no more realtime execution in this period!*/
946 inf->deadl_abs += inf->period;
947 if ( likely(inf->block_abs) )
948 {
949 //treat blocked time as consumed by the domain*/
950 /*inf->cputime += now - inf->block_abs;*/
951 /*penalty is time the domain would have
952 had if it continued to run */
953 pen = (inf->slice - inf->cputime);
954 if ( pen < 0 )
955 pen = 0;
956 /*accumulate all penalties over the periods*/
957 /*inf->short_block_lost_tot += pen;*/
958 /*set penalty to the current value*/
959 inf->short_block_lost_tot = pen;
960 /*not sure which one is better.. but seems to work well...*/
962 if ( inf->short_block_lost_tot )
963 {
964 inf->score[0] = (inf->period << 10) /
965 inf->short_block_lost_tot;
966 #ifdef SEDF_STATS
967 inf->pen_extra_blocks++;
968 #endif
969 if ( extraq_on(inf->vcpu, EXTRA_PEN_Q) )
970 /*remove domain for possible resorting!*/
971 extraq_del(inf->vcpu, EXTRA_PEN_Q);
972 else
973 /*remember that we want to be on the penalty q
974 so that we can continue when we (un-)block
975 in penalty-extratime*/
976 inf->status |= EXTRA_WANT_PEN_Q;
978 /*(re-)add domain to the penalty extraq*/
979 extraq_add_sort_update(inf->vcpu, EXTRA_PEN_Q, 0);
980 }
981 }
983 /*give it a fresh slice in the next period!*/
984 inf->cputime = 0;
985 }
988 static void unblock_long_cons_b(struct sedf_vcpu_info* inf,s_time_t now)
989 {
990 /*Conservative 2b*/
991 /*Treat the unblocking time as a start of a new period */
992 inf->deadl_abs = now + inf->period;
993 inf->cputime = 0;
994 }
997 #define DOMAIN_EDF 1
998 #define DOMAIN_EXTRA_PEN 2
999 #define DOMAIN_EXTRA_UTIL 3
1000 #define DOMAIN_IDLE 4
1001 static inline int get_run_type(struct vcpu* d)
1003 struct sedf_vcpu_info* inf = EDOM_INFO(d);
1004 if (is_idle_vcpu(d))
1005 return DOMAIN_IDLE;
1006 if (inf->status & EXTRA_RUN_PEN)
1007 return DOMAIN_EXTRA_PEN;
1008 if (inf->status & EXTRA_RUN_UTIL)
1009 return DOMAIN_EXTRA_UTIL;
1010 return DOMAIN_EDF;
1014 /*Compares two domains in the relation of whether the one is allowed to
1015 interrupt the others execution.
1016 It returns true (!=0) if a switch to the other domain is good.
1017 Current Priority scheme is as follows:
1018 EDF > L0 (penalty based) extra-time >
1019 L1 (utilization) extra-time > idle-domain
1020 In the same class priorities are assigned as following:
1021 EDF: early deadline > late deadline
1022 L0 extra-time: lower score > higher score*/
1023 static inline int should_switch(struct vcpu *cur,
1024 struct vcpu *other,
1025 s_time_t now)
1027 struct sedf_vcpu_info *cur_inf, *other_inf;
1028 cur_inf = EDOM_INFO(cur);
1029 other_inf = EDOM_INFO(other);
1031 /* Check whether we need to make an earlier scheduling decision. */
1032 if ( PERIOD_BEGIN(other_inf) <
1033 CPU_INFO(other->processor)->current_slice_expires )
1034 return 1;
1036 /* No timing-based switches need to be taken into account here. */
1037 switch ( get_run_type(cur) )
1039 case DOMAIN_EDF:
1040 /* Do not interrupt a running EDF domain. */
1041 return 0;
1042 case DOMAIN_EXTRA_PEN:
1043 /* Check whether we also want the L0 ex-q with lower score. */
1044 return ((other_inf->status & EXTRA_WANT_PEN_Q) &&
1045 (other_inf->score[EXTRA_PEN_Q] <
1046 cur_inf->score[EXTRA_PEN_Q]));
1047 case DOMAIN_EXTRA_UTIL:
1048 /* Check whether we want the L0 extraq. Don't
1049 * switch if both domains want L1 extraq.
1050 */
1051 return !!(other_inf->status & EXTRA_WANT_PEN_Q);
1052 case DOMAIN_IDLE:
1053 return 1;
1056 return 1;
1059 void sedf_wake(struct vcpu *d)
1061 s_time_t now = NOW();
1062 struct sedf_vcpu_info* inf = EDOM_INFO(d);
1064 PRINT(3, "sedf_wake was called, domain-id %i.%i\n",d->domain->domain_id,
1065 d->vcpu_id);
1067 if ( unlikely(is_idle_vcpu(d)) )
1068 return;
1070 if ( unlikely(__task_on_queue(d)) )
1072 PRINT(3,"\tdomain %i.%i is already in some queue\n",
1073 d->domain->domain_id, d->vcpu_id);
1074 return;
1077 ASSERT(!sedf_runnable(d));
1078 inf->status &= ~SEDF_ASLEEP;
1079 ASSERT(!extraq_on(d, EXTRA_UTIL_Q));
1080 ASSERT(!extraq_on(d, EXTRA_PEN_Q));
1082 if ( unlikely(inf->deadl_abs == 0) )
1084 /*initial setup of the deadline*/
1085 inf->deadl_abs = now + inf->slice;
1088 PRINT(3, "waking up domain %i.%i (deadl= %"PRIu64" period= %"PRIu64
1089 "now= %"PRIu64")\n",
1090 d->domain->domain_id, d->vcpu_id, inf->deadl_abs, inf->period, now);
1092 #ifdef SEDF_STATS
1093 inf->block_tot++;
1094 #endif
1096 if ( unlikely(now < PERIOD_BEGIN(inf)) )
1098 PRINT(4,"extratime unblock\n");
1099 /* unblocking in extra-time! */
1100 if ( inf->status & EXTRA_WANT_PEN_Q )
1102 /*we have a domain that wants compensation
1103 for block penalty and did just block in
1104 its compensation time. Give it another
1105 chance!*/
1106 extraq_add_sort_update(d, EXTRA_PEN_Q, 0);
1108 extraq_check_add_unblocked(d, 0);
1110 else
1112 if ( now < inf->deadl_abs )
1114 PRINT(4,"short unblocking\n");
1115 /*short blocking*/
1116 #ifdef SEDF_STATS
1117 inf->short_block_tot++;
1118 #endif
1119 unblock_short_extra_support(inf, now);
1121 extraq_check_add_unblocked(d, 1);
1123 else
1125 PRINT(4,"long unblocking\n");
1126 /*long unblocking*/
1127 #ifdef SEDF_STATS
1128 inf->long_block_tot++;
1129 #endif
1130 unblock_long_cons_b(inf, now);
1132 extraq_check_add_unblocked(d, 1);
1136 PRINT(3, "woke up domain %i.%i (deadl= %"PRIu64" period= %"PRIu64
1137 "now= %"PRIu64")\n",
1138 d->domain->domain_id, d->vcpu_id, inf->deadl_abs,
1139 inf->period, now);
1141 if ( PERIOD_BEGIN(inf) > now )
1143 __add_to_waitqueue_sort(d);
1144 PRINT(3,"added to waitq\n");
1146 else
1148 __add_to_runqueue_sort(d);
1149 PRINT(3,"added to runq\n");
1152 #ifdef SEDF_STATS
1153 /*do some statistics here...*/
1154 if ( inf->block_abs != 0 )
1156 inf->block_time_tot += now - inf->block_abs;
1157 inf->penalty_time_tot +=
1158 PERIOD_BEGIN(inf) + inf->cputime - inf->block_abs;
1160 #endif
1162 /*sanity check: make sure each extra-aware domain IS on the util-q!*/
1163 ASSERT(IMPLY(inf->status & EXTRA_AWARE, extraq_on(d, EXTRA_UTIL_Q)));
1164 ASSERT(__task_on_queue(d));
1165 /*check whether the awakened task needs to invoke the do_schedule
1166 routine. Try to avoid unnecessary runs but:
1167 Save approximation: Always switch to scheduler!*/
1168 ASSERT(d->processor >= 0);
1169 ASSERT(d->processor < NR_CPUS);
1170 ASSERT(schedule_data[d->processor].curr);
1172 if ( should_switch(schedule_data[d->processor].curr, d, now) )
1173 cpu_raise_softirq(d->processor, SCHEDULE_SOFTIRQ);
1177 static int sedf_set_affinity(struct vcpu *v, cpumask_t *affinity)
1179 if ( v == current )
1180 return cpu_isset(v->processor, *affinity) ? 0 : -EBUSY;
1182 vcpu_pause(v);
1183 v->cpu_affinity = *affinity;
1184 v->processor = first_cpu(v->cpu_affinity);
1185 vcpu_unpause(v);
1187 return 0;
1191 /* Print a lot of useful information about a domains in the system */
1192 static void sedf_dump_domain(struct vcpu *d)
1194 printk("%i.%i has=%c ", d->domain->domain_id, d->vcpu_id,
1195 test_bit(_VCPUF_running, &d->vcpu_flags) ? 'T':'F');
1196 printk("p=%"PRIu64" sl=%"PRIu64" ddl=%"PRIu64" w=%hu"
1197 " sc=%i xtr(%s)=%"PRIu64" ew=%hu",
1198 EDOM_INFO(d)->period, EDOM_INFO(d)->slice, EDOM_INFO(d)->deadl_abs,
1199 EDOM_INFO(d)->weight,
1200 EDOM_INFO(d)->score[EXTRA_UTIL_Q],
1201 (EDOM_INFO(d)->status & EXTRA_AWARE) ? "yes" : "no",
1202 EDOM_INFO(d)->extra_time_tot, EDOM_INFO(d)->extraweight);
1204 #ifdef SEDF_STATS
1205 if ( EDOM_INFO(d)->block_time_tot != 0 )
1206 printf(" pen=%"PRIu64"%%", (EDOM_INFO(d)->penalty_time_tot * 100) /
1207 EDOM_INFO(d)->block_time_tot);
1208 if ( EDOM_INFO(d)->block_tot != 0 )
1209 printf("\n blks=%u sh=%u (%u%%) (shc=%u (%u%%) shex=%i "\
1210 "shexsl=%i) l=%u (%u%%) avg: b=%"PRIu64" p=%"PRIu64"",
1211 EDOM_INFO(d)->block_tot, EDOM_INFO(d)->short_block_tot,
1212 (EDOM_INFO(d)->short_block_tot * 100)
1213 / EDOM_INFO(d)->block_tot, EDOM_INFO(d)->short_cont,
1214 (EDOM_INFO(d)->short_cont * 100) / EDOM_INFO(d)->block_tot,
1215 EDOM_INFO(d)->pen_extra_blocks,
1216 EDOM_INFO(d)->pen_extra_slices,
1217 EDOM_INFO(d)->long_block_tot,
1218 (EDOM_INFO(d)->long_block_tot * 100) / EDOM_INFO(d)->block_tot,
1219 (EDOM_INFO(d)->block_time_tot) / EDOM_INFO(d)->block_tot,
1220 (EDOM_INFO(d)->penalty_time_tot) / EDOM_INFO(d)->block_tot);
1221 #endif
1222 printf("\n");
1226 /* dumps all domains on hte specified cpu */
1227 static void sedf_dump_cpu_state(int i)
1229 struct list_head *list, *queue, *tmp;
1230 struct sedf_vcpu_info *d_inf;
1231 struct domain *d;
1232 struct vcpu *ed;
1233 int loop = 0;
1235 printk("now=%"PRIu64"\n",NOW());
1236 queue = RUNQ(i);
1237 printk("RUNQ rq %lx n: %lx, p: %lx\n", (unsigned long)queue,
1238 (unsigned long) queue->next, (unsigned long) queue->prev);
1239 list_for_each_safe ( list, tmp, queue )
1241 printk("%3d: ",loop++);
1242 d_inf = list_entry(list, struct sedf_vcpu_info, list);
1243 sedf_dump_domain(d_inf->vcpu);
1246 queue = WAITQ(i); loop = 0;
1247 printk("\nWAITQ rq %lx n: %lx, p: %lx\n", (unsigned long)queue,
1248 (unsigned long) queue->next, (unsigned long) queue->prev);
1249 list_for_each_safe ( list, tmp, queue )
1251 printk("%3d: ",loop++);
1252 d_inf = list_entry(list, struct sedf_vcpu_info, list);
1253 sedf_dump_domain(d_inf->vcpu);
1256 queue = EXTRAQ(i,EXTRA_PEN_Q); loop = 0;
1257 printk("\nEXTRAQ (penalty) rq %lx n: %lx, p: %lx\n",
1258 (unsigned long)queue, (unsigned long) queue->next,
1259 (unsigned long) queue->prev);
1260 list_for_each_safe ( list, tmp, queue )
1262 d_inf = list_entry(list, struct sedf_vcpu_info,
1263 extralist[EXTRA_PEN_Q]);
1264 printk("%3d: ",loop++);
1265 sedf_dump_domain(d_inf->vcpu);
1268 queue = EXTRAQ(i,EXTRA_UTIL_Q); loop = 0;
1269 printk("\nEXTRAQ (utilization) rq %lx n: %lx, p: %lx\n",
1270 (unsigned long)queue, (unsigned long) queue->next,
1271 (unsigned long) queue->prev);
1272 list_for_each_safe ( list, tmp, queue )
1274 d_inf = list_entry(list, struct sedf_vcpu_info,
1275 extralist[EXTRA_UTIL_Q]);
1276 printk("%3d: ",loop++);
1277 sedf_dump_domain(d_inf->vcpu);
1280 loop = 0;
1281 printk("\nnot on Q\n");
1283 for_each_domain ( d )
1285 for_each_vcpu(d, ed)
1287 if ( !__task_on_queue(ed) && (ed->processor == i) )
1289 printk("%3d: ",loop++);
1290 sedf_dump_domain(ed);
1297 /* Adjusts periods and slices of the domains accordingly to their weights. */
1298 static int sedf_adjust_weights(struct sched_adjdom_cmd *cmd)
1300 struct vcpu *p;
1301 struct domain *d;
1302 int sumw[NR_CPUS];
1303 s_time_t sumt[NR_CPUS];
1304 int cpu;
1306 for ( cpu = 0; cpu < NR_CPUS; cpu++ )
1308 sumw[cpu] = 0;
1309 sumt[cpu] = 0;
1312 /* Sum across all weights. */
1313 for_each_domain( d )
1315 for_each_vcpu( d, p )
1317 if ( EDOM_INFO(p)->weight )
1319 sumw[p->processor] += EDOM_INFO(p)->weight;
1321 else
1323 /*don't modify domains who don't have a weight, but sum
1324 up the time they need, projected to a WEIGHT_PERIOD,
1325 so that this time is not given to the weight-driven
1326 domains*/
1327 /*check for overflows*/
1328 ASSERT((WEIGHT_PERIOD < ULONG_MAX)
1329 && (EDOM_INFO(p)->slice_orig < ULONG_MAX));
1330 sumt[p->processor] +=
1331 (WEIGHT_PERIOD * EDOM_INFO(p)->slice_orig) /
1332 EDOM_INFO(p)->period_orig;
1337 /* Adjust all slices (and periods) to the new weight. */
1338 for_each_domain( d )
1340 for_each_vcpu ( d, p )
1342 if ( EDOM_INFO(p)->weight )
1344 EDOM_INFO(p)->period_orig =
1345 EDOM_INFO(p)->period = WEIGHT_PERIOD;
1346 EDOM_INFO(p)->slice_orig =
1347 EDOM_INFO(p)->slice =
1348 (EDOM_INFO(p)->weight *
1349 (WEIGHT_PERIOD - WEIGHT_SAFETY - sumt[p->processor])) /
1350 sumw[p->processor];
1355 return 0;
1359 /* set or fetch domain scheduling parameters */
1360 static int sedf_adjdom(struct domain *p, struct sched_adjdom_cmd *cmd)
1362 struct vcpu *v;
1364 PRINT(2,"sedf_adjdom was called, domain-id %i new period %"PRIu64" "
1365 "new slice %"PRIu64"\nlatency %"PRIu64" extra:%s\n",
1366 p->domain_id, cmd->u.sedf.period, cmd->u.sedf.slice,
1367 cmd->u.sedf.latency, (cmd->u.sedf.extratime)?"yes":"no");
1369 if ( cmd->direction == SCHED_INFO_PUT )
1371 /* Check for sane parameters. */
1372 if ( !cmd->u.sedf.period && !cmd->u.sedf.weight )
1373 return -EINVAL;
1374 if ( cmd->u.sedf.weight )
1376 if ( (cmd->u.sedf.extratime & EXTRA_AWARE) &&
1377 (!cmd->u.sedf.period) )
1379 /* Weight-driven domains with extratime only. */
1380 for_each_vcpu ( p, v )
1382 EDOM_INFO(v)->extraweight = cmd->u.sedf.weight;
1383 EDOM_INFO(v)->weight = 0;
1384 EDOM_INFO(v)->slice = 0;
1385 EDOM_INFO(v)->period = WEIGHT_PERIOD;
1388 else
1390 /* Weight-driven domains with real-time execution. */
1391 for_each_vcpu ( p, v )
1392 EDOM_INFO(v)->weight = cmd->u.sedf.weight;
1395 else
1397 /* Time-driven domains. */
1398 for_each_vcpu ( p, v )
1400 /*
1401 * Sanity checking: note that disabling extra weight requires
1402 * that we set a non-zero slice.
1403 */
1404 if ( (cmd->u.sedf.period > PERIOD_MAX) ||
1405 (cmd->u.sedf.period < PERIOD_MIN) ||
1406 (cmd->u.sedf.slice > cmd->u.sedf.period) ||
1407 (cmd->u.sedf.slice < SLICE_MIN) )
1408 return -EINVAL;
1409 EDOM_INFO(v)->weight = 0;
1410 EDOM_INFO(v)->extraweight = 0;
1411 EDOM_INFO(v)->period_orig =
1412 EDOM_INFO(v)->period = cmd->u.sedf.period;
1413 EDOM_INFO(v)->slice_orig =
1414 EDOM_INFO(v)->slice = cmd->u.sedf.slice;
1418 if ( sedf_adjust_weights(cmd) )
1419 return -EINVAL;
1421 for_each_vcpu ( p, v )
1423 EDOM_INFO(v)->status =
1424 (EDOM_INFO(v)->status &
1425 ~EXTRA_AWARE) | (cmd->u.sedf.extratime & EXTRA_AWARE);
1426 EDOM_INFO(v)->latency = cmd->u.sedf.latency;
1427 extraq_check(v);
1430 else if ( cmd->direction == SCHED_INFO_GET )
1432 cmd->u.sedf.period = EDOM_INFO(p->vcpu[0])->period;
1433 cmd->u.sedf.slice = EDOM_INFO(p->vcpu[0])->slice;
1434 cmd->u.sedf.extratime = EDOM_INFO(p->vcpu[0])->status & EXTRA_AWARE;
1435 cmd->u.sedf.latency = EDOM_INFO(p->vcpu[0])->latency;
1436 cmd->u.sedf.weight = EDOM_INFO(p->vcpu[0])->weight;
1439 PRINT(2,"sedf_adjdom_finished\n");
1440 return 0;
1443 struct scheduler sched_sedf_def = {
1444 .name = "Simple EDF Scheduler",
1445 .opt_name = "sedf",
1446 .sched_id = SCHED_SEDF,
1448 .init_vcpu = sedf_init_vcpu,
1449 .destroy_domain = sedf_destroy_domain,
1451 .do_schedule = sedf_do_schedule,
1452 .dump_cpu_state = sedf_dump_cpu_state,
1453 .sleep = sedf_sleep,
1454 .wake = sedf_wake,
1455 .adjdom = sedf_adjdom,
1456 .set_affinity = sedf_set_affinity
1457 };
1459 /*
1460 * Local variables:
1461 * mode: C
1462 * c-set-style: "BSD"
1463 * c-basic-offset: 4
1464 * tab-width: 4
1465 * indent-tabs-mode: nil
1466 * End:
1467 */
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Imagining FashionText
Todd Perry
3 min readAug 17, 2021
I might build a software application that allows a Buyer to pay a Seller in return for performing the following tasks:
1) Buyer attaches a collection of texts to a “spool” within the app, and the app would also provide a terms of service agreement and a content moderation service for the purpose of holding back Buyer from doing bad things, such as attaching texts in violation of copyright restrictions, etc.
2) The spool would also specify a number of threads that Seller would be expected to “pull” from the spool, prior to a “closing date,” where pulling a thread could refer to the concept of selecting a “string” from the collection of texts and then inviting the puller to ask a question about the string and then maybe supply zero or more answers to their own question, and the question could also be a statement, or the answers could be totally satirical, because these threads and the spool from which they are pulled could be as serious or silly as the collaborators in question want them to be.
3) The spool would also define a closing routine that might involve an hour long video chat between Seller and Buyer followed by a payment, at which point the app would “certify” the spool for distribution and resale via the app’s platform interface, and so on and so forth.
There would be lots of design variations for entrepreneurs in this space to explore, and I would like to create an open source reference implementation of this idea so that lots of people can run online services that generate and market these sorts of virtual spools of threads.
“Threads” would be like any other tree structure of text based comments that might appear on a computer screen, but grouping them into spools that could be created collaboratively by buyers and sellers might facilitate the development of libraries of spools that could be resold at higher and higher prices over time.
For example, if I acted as a Buyer and someone else with a bigger following than me (or maybe just a different following) acted as the Seller, in order to generate a spool of threads that were pulled from this article, “our” new spool could create extra distribution for the ideas in this article, and there might eventually be more and more people who would pay a premium over what I paid, as the original Buyer, so that they too can exercise the right to resell the spool at their discretion, and the original Seller and all of the previous owners could potentially collect additional royalties each time the spool is resold.
And, the price of well-formed spools that are based on this article might keep going up over time is because this article could become a foundational text for a whole class of successful apps that might eventually challenge the potentially unsustainable grip on power that Big Tech’s algorithms currently hold in relation to human beings.
Finally, each “spool” could be like a new crypto currency or maybe an NFT, but the value creation that I have in mind would be an elaboration of such ideas in the form of working code, and, in the long term, libraries of spools could become a record of useful training data for future AI.
NOTE: This text has not changed much since I wrote it in 2021, but I added the AI-generated header and footer image combinations in 2024.
Please visit fashiontext.com for more information.
--
--
Todd Perry
Todd taught computer science on the east coast from 2001 to 2005, and then he developed software in Palo Alto, CA, from 2006 to 2010, first at PT and then FB.
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| 0.945714 |
Aspectos
Informar un problema Ver fuente Por la noche · 7.2 · 7.1 · 7.0 · 6.5 · 6.4
En esta página, se explican los conceptos básicos y los beneficios de utilizar aspectos y brinda una solución simple y avanzada ejemplos.
Los aspectos permiten aumentar los gráficos de dependencias de compilación con información adicional y acciones. Estas son algunas situaciones típicas en las que los aspectos pueden ser útiles:
• Los IDE que integran Bazel pueden usar aspectos para recopilar información sobre el en un proyecto final.
• Las herramientas de generación de código pueden aprovechar aspectos para ejecutar en sus entradas independiente del objetivo. Por ejemplo, los archivos BUILD pueden especificar una jerarquía de la biblioteca de protobuf y las reglas específicas de cada lenguaje pueden usar aspectos para adjuntar acciones que generan código de compatibilidad de protobuf para un lenguaje en particular.
Aspectos básicos de los aspectos
Los archivos BUILD proporcionan una descripción del código fuente de un proyecto: ¿de qué fuente? como parte del proyecto, a partir de qué artefactos (destinos) se deben compilar esos archivos, cuáles son las dependencias entre ellos, etc. Bazel usa esta información para realizar una compilación, es decir, descifra el conjunto de acciones necesarios para producir los artefactos (como la ejecución del compilador o vinculador) y ejecuta esas acciones. Bazel logra esto construyendo una dependencia gráfico entre los objetivos y visitar este gráfico para recopilar esas acciones.
Considera el siguiente archivo BUILD:
java_library(name = 'W', ...)
java_library(name = 'Y', deps = [':W'], ...)
java_library(name = 'Z', deps = [':W'], ...)
java_library(name = 'Q', ...)
java_library(name = 'T', deps = [':Q'], ...)
java_library(name = 'X', deps = [':Y',':Z'], runtime_deps = [':T'], ...)
Este archivo BUILD define un gráfico de dependencia que se muestra en la siguiente figura:
Gráfico de compilación
Figura 1: Gráfico de dependencia de archivos de BUILD
Bazel analiza este gráfico de dependencias llamando a una función de implementación de la regla correspondiente (en este caso, "java_library") para cada objetivo en el ejemplo anterior. Las funciones de implementación de reglas generan acciones compilar artefactos, como archivos .jar, y pasar información, como ubicaciones y nombres de esos artefactos, a las dependencias inversas de esos objetivos en proveedores.
Los aspectos son similares a las reglas, ya que tienen una función de implementación genera acciones y devuelve proveedores. Sin embargo, su poder proviene de la forma en que el gráfico de dependencias está creado para ellos. Un aspecto tiene una implementación y una lista de todos los atributos que se propagan. Considera un aspecto A que se propaga a lo largo de atributos llamados “deps”. Este aspecto se puede aplicar un destino X, lo que produce un nodo de aplicación de aspecto A(X). Durante su aplicación, el aspecto A se aplica de manera recursiva a todos los objetivos a los que X hace referencia en sus “dependencias” (todos los atributos de la lista de propagación de A).
Por lo tanto, un solo acto de aplicar el aspecto A a un objetivo X produce un “gráfico de sombras” de el gráfico de dependencia original de los objetivos que se muestra en la siguiente figura:
Crear gráfico con aspecto
Figura 2: Compilar un gráfico con aspectos
Los únicos bordes sombreados son aquellos a lo largo de los atributos en el conjunto de propagación, por lo que el borde runtime_deps no se sombrea en este ejemplo. Luego, se invoca una función de implementación de aspecto en todos los nodos en el gráfico paralelo, de manera similar a como se invocan las implementaciones de reglas en los nodos del gráfico original.
Ejemplo simple
Este ejemplo demuestra cómo imprimir de manera recursiva los archivos fuente para un y todas sus dependencias que tienen un atributo deps. Muestra una implementación de aspecto, una definición de aspecto y cómo invocar este aspecto desde la línea de comandos de Bazel.
def _print_aspect_impl(target, ctx):
# Make sure the rule has a srcs attribute.
if hasattr(ctx.rule.attr, 'srcs'):
# Iterate through the files that make up the sources and
# print their paths.
for src in ctx.rule.attr.srcs:
for f in src.files.to_list():
print(f.path)
return []
print_aspect = aspect(
implementation = _print_aspect_impl,
attr_aspects = ['deps'],
)
Desglosemos el ejemplo en sus partes y examinemos cada una de forma individual.
Definición de aspecto
print_aspect = aspect(
implementation = _print_aspect_impl,
attr_aspects = ['deps'],
)
Las definiciones de aspecto son similares a las definiciones de reglas y se definen con La función aspect
Al igual que una regla, un aspecto tiene una función de implementación que, en este caso, es _print_aspect_impl
attr_aspects es una lista de atributos de reglas a través de los cuales se propaga el aspecto. En este caso, el aspecto se propagará a lo largo del atributo deps del las reglas a las que se aplica.
Otro argumento común para attr_aspects es ['*'], que propagaría el en todos los atributos de una regla.
Implementación de Aspect
def _print_aspect_impl(target, ctx):
# Make sure the rule has a srcs attribute.
if hasattr(ctx.rule.attr, 'srcs'):
# Iterate through the files that make up the sources and
# print their paths.
for src in ctx.rule.attr.srcs:
for f in src.files.to_list():
print(f.path)
return []
Las funciones de implementación de Aspecto son similares a las de la implementación de reglas funciones. Muestran providers, pueden generar actions y toma dos argumentos:
• target: Es el objetivo al que se aplica el aspecto.
• ctx: Es un objeto ctx que se puede usar para acceder a los atributos. y generar resultados y acciones.
La función de implementación puede acceder a los atributos de la regla objetivo mediante ctx.rule.attr Puede examinar a los proveedores que son que proporciona el destino al que se aplica (a través del argumento target).
Los aspectos son obligatorios para mostrar una lista de proveedores. En este ejemplo, el aspecto no proporciona nada, por lo que muestra una lista vacía.
Cómo invocar el aspecto con la línea de comandos
La forma más sencilla de aplicar un aspecto es desde la línea de comandos usando el --aspects argumento. Suponiendo que los aspectos anteriores se hayan definido en un archivo llamado print.bzl esto:
bazel build //MyExample:example --aspects print.bzl%print_aspect
aplicaría el print_aspect al example objetivo y todos los reglas de destino a las que se puede acceder de forma recursiva a través del atributo deps
La marca --aspects toma un argumento, que es una especificación del aspecto en el formato <extension file label>%<aspect top-level name>.
Ejemplo avanzado
En el siguiente ejemplo, se muestra el uso de un aspecto de una regla objetivo que registra los archivos en los destinos y, posiblemente, los filtre por extensión. Muestra cómo usar un proveedor para devolver valores, cómo usar parámetros para pasar un argumento en la implementación de un aspecto y cómo invocar un aspecto a partir de una regla.
Archivo file_count.bzl:
FileCountInfo = provider(
fields = {
'count' : 'number of files'
}
)
def _file_count_aspect_impl(target, ctx):
count = 0
# Make sure the rule has a srcs attribute.
if hasattr(ctx.rule.attr, 'srcs'):
# Iterate through the sources counting files
for src in ctx.rule.attr.srcs:
for f in src.files.to_list():
if ctx.attr.extension == '*' or ctx.attr.extension == f.extension:
count = count + 1
# Get the counts from our dependencies.
for dep in ctx.rule.attr.deps:
count = count + dep[FileCountInfo].count
return [FileCountInfo(count = count)]
file_count_aspect = aspect(
implementation = _file_count_aspect_impl,
attr_aspects = ['deps'],
attrs = {
'extension' : attr.string(values = ['*', 'h', 'cc']),
}
)
def _file_count_rule_impl(ctx):
for dep in ctx.attr.deps:
print(dep[FileCountInfo].count)
file_count_rule = rule(
implementation = _file_count_rule_impl,
attrs = {
'deps' : attr.label_list(aspects = [file_count_aspect]),
'extension' : attr.string(default = '*'),
},
)
Archivo BUILD.bazel:
load('//:file_count.bzl', 'file_count_rule')
cc_library(
name = 'lib',
srcs = [
'lib.h',
'lib.cc',
],
)
cc_binary(
name = 'app',
srcs = [
'app.h',
'app.cc',
'main.cc',
],
deps = ['lib'],
)
file_count_rule(
name = 'file_count',
deps = ['app'],
extension = 'h',
)
Definición de aspecto
file_count_aspect = aspect(
implementation = _file_count_aspect_impl,
attr_aspects = ['deps'],
attrs = {
'extension' : attr.string(values = ['*', 'h', 'cc']),
}
)
En este ejemplo, se muestra cómo se propaga el aspecto a través del atributo deps.
attrs define un conjunto de atributos para un aspecto. Atributos de aspecto público definen parámetros y solo pueden ser de tipos bool, int o string. Para los aspectos propagados por reglas, los parámetros int y string deben tener Se especificó values en ellos. Este ejemplo tiene un parámetro llamado extension que puede tener "*", "h" o "cc" como un valor.
Para los aspectos propagados por regla, los valores de los parámetros se toman de la regla que solicita el aspecto con el atributo de la regla que tiene el mismo nombre y tipo. (consulta la definición de file_count_rule).
Para los aspectos de la línea de comandos, los valores de los parámetros se pueden pasar con --aspects_parameters marca. Se puede aplicar la restricción values de los parámetros int y string omitido.
Los aspectos también pueden tener atributos privados de los tipos label o label_list Los atributos de etiqueta privada se pueden usar para especificar dependencias herramientas o bibliotecas necesarias para acciones generadas por aspectos. No hay un atributo privado definido en este ejemplo, pero el siguiente fragmento de código demuestra cómo podrías pasar una herramienta a un aspecto:
...
attrs = {
'_protoc' : attr.label(
default = Label('//tools:protoc'),
executable = True,
cfg = "exec"
)
}
...
Implementación de Aspect
FileCountInfo = provider(
fields = {
'count' : 'number of files'
}
)
def _file_count_aspect_impl(target, ctx):
count = 0
# Make sure the rule has a srcs attribute.
if hasattr(ctx.rule.attr, 'srcs'):
# Iterate through the sources counting files
for src in ctx.rule.attr.srcs:
for f in src.files.to_list():
if ctx.attr.extension == '*' or ctx.attr.extension == f.extension:
count = count + 1
# Get the counts from our dependencies.
for dep in ctx.rule.attr.deps:
count = count + dep[FileCountInfo].count
return [FileCountInfo(count = count)]
Al igual que una función de implementación de reglas, una función de implementación de aspectos devuelve una estructura de proveedores a los que pueden acceder sus dependencias.
En este ejemplo, FileCountInfo se define como un proveedor que tiene un count. Una práctica recomendada es definir explícitamente los campos de un con el atributo fields.
El conjunto de proveedores para una aplicación de aspecto A(X) es la unión de proveedores. que provienen de la implementación de una regla para el objetivo X y de implementación del aspecto A. Los proveedores que propaga la implementación de una regla se crean y se inmovilizan antes de que se apliquen los aspectos y no se pueden modificar desde una aspecto. Es un error si un objetivo y un aspecto que se le aplica cada uno proporcionar a un proveedor del mismo tipo, a excepción de OutputGroupInfo (que está fusionado, siempre que el la regla y el aspecto especifican diferentes grupos de salida) y InstrumentedFilesInfo (toma del aspecto). Esto significa que las implementaciones de aspectos nunca se muestra DefaultInfo.
Los parámetros y los atributos privados se pasan en los atributos de la ctx En este ejemplo, se hace referencia al parámetro extension y determina qué archivos contar.
En el caso de los proveedores recurrentes, los valores de los atributos con los que el aspecto se propaga (de la lista attr_aspects) se reemplazan por los resultados de una aplicación del aspecto. Por ejemplo, si el objetivo X tiene Y y Z en sus dependencias, ctx.rule.attr.deps para A(X) será [A(Y), A(Z)]. En este ejemplo, ctx.rule.attr.deps son objetos de destino que son resultados de la aplicación del aspecto a las “deps” del destino original al que se aplicó el aspecto.
En el ejemplo, el aspecto accede al proveedor de FileCountInfo desde el destino para acumular la cantidad total transitiva de archivos.
Invoca el aspecto de una regla
def _file_count_rule_impl(ctx):
for dep in ctx.attr.deps:
print(dep[FileCountInfo].count)
file_count_rule = rule(
implementation = _file_count_rule_impl,
attrs = {
'deps' : attr.label_list(aspects = [file_count_aspect]),
'extension' : attr.string(default = '*'),
},
)
La implementación de reglas muestra cómo acceder a FileCountInfo. a través del ctx.attr.deps.
La definición de la regla muestra cómo definir un parámetro (extension) y asígnale un valor predeterminado (*). Ten en cuenta que tener un valor predeterminado que no fue uno de "cc", "h" ni "*" sería un error debido al restricciones aplicadas al parámetro en la definición de aspecto.
Cómo invocar un aspecto a través de una regla objetivo
load('//:file_count.bzl', 'file_count_rule')
cc_binary(
name = 'app',
...
)
file_count_rule(
name = 'file_count',
deps = ['app'],
extension = 'h',
)
Esto muestra cómo pasar el parámetro extension al aspecto a través de la regla. Como el parámetro extension tiene un valor predeterminado en el implementación de reglas, extension se consideraría un parámetro opcional.
Cuando se crea el destino file_count, nuestro aspecto se evaluará en función de lo siguiente: y todos los destinos accesibles de forma recurrente a través de deps.
Referencias
|
__label__pos
| 0.884218 |
Bug 1452706 - Add the 'expected' arguments to throws/rejects for devtools/shared/sourcemap. r?yulia draft
authorMark Banner <[email protected]>
Tue, 03 Jul 2018 20:16:20 +0100
changeset 814484 535598b33b49bb5fef37fb072d93fcd2f23e7b0a
parent 814369 90be04d99fc7941cb9b7186bf5f95e184a4e989a
child 814485 59e979897e9cc2aa262a9112aac7debf91596fac
push id115229
push userbmo:[email protected]
push dateThu, 05 Jul 2018 13:40:07 +0000
reviewersyulia
bugs1452706
milestone63.0a1
Bug 1452706 - Add the 'expected' arguments to throws/rejects for devtools/shared/sourcemap. r?yulia MozReview-Commit-ID: AdOD0Txwdi7
devtools/shared/sourcemap/tests/unit/test_base64.js
devtools/shared/sourcemap/tests/unit/test_source_map_generator.js
devtools/shared/sourcemap/tests/unit/test_source_node.js
--- a/devtools/shared/sourcemap/tests/unit/test_base64.js
+++ b/devtools/shared/sourcemap/tests/unit/test_base64.js
@@ -61,20 +61,20 @@ var SOURCE_MAP_TEST_MODULE =
* http://opensource.org/licenses/BSD-3-Clause
*/
var base64 = __webpack_require__(1);
exports['test out of range encoding'] = function (assert) {
assert.throws(function () {
base64.encode(-1);
- });
+ }, /Must be between 0 and 63/);
assert.throws(function () {
base64.encode(64);
- });
+ }, /Must be between 0 and 63/);
};
exports['test out of range decoding'] = function (assert) {
assert.equal(base64.decode('='.charCodeAt(0)), -1);
};
exports['test normal encoding and decoding'] = function (assert) {
for (var i = 0; i < 64; i++) {
--- a/devtools/shared/sourcemap/tests/unit/test_source_map_generator.js
+++ b/devtools/shared/sourcemap/tests/unit/test_source_map_generator.js
@@ -135,38 +135,38 @@ var SOURCE_MAP_TEST_MODULE =
var map = new SourceMapGenerator({
file: 'generated-foo.js',
sourceRoot: '.'
});
// Not enough info.
assert.throws(function () {
map.addMapping({});
- });
+ }, /"generated" is a required argument/);
// Original file position, but no source.
assert.throws(function () {
map.addMapping({
generated: { line: 1, column: 1 },
original: { line: 1, column: 1 }
});
- });
+ }, /Invalid mapping/);
};
exports['test adding mappings with skipValidation'] = function (assert) {
var map = new SourceMapGenerator({
file: 'generated-foo.js',
sourceRoot: '.',
skipValidation: true
});
// Not enough info, caught by `util.getArgs`
assert.throws(function () {
map.addMapping({});
- });
+ }, /"generated" is a required argument/);
// Original file position, but no source. Not checked.
assert.doesNotThrow(function () {
map.addMapping({
generated: { line: 1, column: 1 },
original: { line: 1, column: 1 }
});
});
@@ -391,17 +391,17 @@ var SOURCE_MAP_TEST_MODULE =
exports['test applySourceMap throws when file is missing'] = function (assert) {
var map = new SourceMapGenerator({
file: 'test.js'
});
var map2 = new SourceMapGenerator();
assert.throws(function() {
map.applySourceMap(new SourceMapConsumer(map2.toJSON()));
- });
+ }, /Error: SourceMapGenerator.prototype.applySourceMap requires either an explicit source file/);
};
exports['test the two additional parameters of applySourceMap'] = function (assert) {
// Assume the following directory structure:
//
// http://foo.org/
// bar.coffee
// app/
--- a/devtools/shared/sourcemap/tests/unit/test_source_node.js
+++ b/devtools/shared/sourcemap/tests/unit/test_source_node.js
@@ -85,20 +85,20 @@ var SOURCE_MAP_TEST_MODULE =
node.add(['function foo() {',
new SourceNode(null, null, null,
'return 10;'),
'}']);
// Adding other stuff doesn't.
assert.throws(function () {
node.add({});
- });
+ }, /TypeError: Expected a SourceNode, string, or an array of SourceNodes and strings/);
assert.throws(function () {
node.add(function () {});
- });
+ }, /TypeError: Expected a SourceNode, string, or an array of SourceNodes and strings/);
};
exports['test .prepend()'] = function (assert) {
var node = new SourceNode(null, null, null);
// Prepending a string works.
node.prepend('function noop() {}');
assert.equal(node.children[0], 'function noop() {}');
@@ -120,20 +120,20 @@ var SOURCE_MAP_TEST_MODULE =
assert.equal(node.children[2], '}');
assert.equal(node.children[3], '');
assert.equal(node.children[4], 'function noop() {}');
assert.equal(node.children.length, 5);
// Prepending other stuff doesn't.
assert.throws(function () {
node.prepend({});
- });
+ }, /TypeError: Expected a SourceNode, string, or an array of SourceNodes and strings/);
assert.throws(function () {
node.prepend(function () {});
- });
+ }, /TypeError: Expected a SourceNode, string, or an array of SourceNodes and strings/);
};
exports['test .toString()'] = function (assert) {
assert.equal((new SourceNode(null, null, null,
['function foo() {',
new SourceNode(null, null, null, 'return 10;'),
'}'])).toString(),
'function foo() {return 10;}');
|
__label__pos
| 0.984357 |
What is the code for copyright?
What is the code for copyright?
Copyright symbol
©
Copyright sign
See also U+2117 ℗ SOUND RECORDING COPYRIGHT (HTML ℗ · ©sr ) U+1F12F ? COPYLEFT SYMBOL (HTML ? )
Different from
Different from U+24B8 Ⓒ CIRCLED LATIN CAPITAL LETTER C (HTML Ⓒ )
How do you add a copyright symbol in CSS?
CSS doesn’t use HTML’s entities; it uses its own unicode escape sequences. You need to use \00a9 for the copyright symbol.
How do I add a trademark symbol in HTML?
Alternatively, you can also use the following shortcuts: ®; for registered trademark symbol ® ™ for trademark symbol ™…Inserting Trademark Symbols in HTML
1. For the ™ symbol, type in ™
2. For © symbol, type in ©
3. For ® symbol, type in ®
Can you copyright code?
Is the code copyrighted? Almost certainly yes. Under copyright law, source code is a literary work (like a book). And, just like any other writing, it is immediately copyrighted regardless of the author registering it with the U.S. Copyright Office.
How do you write copyright?
To insert the copyright symbol, press Ctrl+Alt+C. To insert the trademark symbol, press Ctrl+Alt+T.
How do you add a copyright code?
Use the Ctrl + . or Ctrl + ~ shortcut to invoke the Code Actions Menu and select Add Copyright Header from the menu.
How do you write a fraction in HTML?
Text on web documents is written straight across with where only one character can take up one space on the line. Characters can be moved vertically, but cannot have another character immediately below them. To write a fraction, people write fractions with a slash symbol (/) between the numbers.
How do I license my code?
Applying a license to your open source projects
1. Open your GitHub repository in a browser.
2. In the root directory, click on Create new file .
3. Name the file “LICENSE”.
4. Click on Choose a license template .
5. Pick one of the licenses (all the ones mentioned in this article are there).
6. Once chosen, click on Review and submit .
Should I copyright source code?
The Copyright Office strongly prefers that you submit your copyright application using a source code deposit. You can submit a deposit using the object code of the computer program; however, your claim will be subject to the Copyright Office’s Rule of Doubt.
How do you make a copyright symbol on a keyboard?
On the keyboard. The copyright symbol is made on most PCs by holding the ALT key and typing 0169 on the numeric keypad to the right. Another easy way to make a copyright symbol is by pressing CTRL + ALT + C. This command works well on laptops that do not have a numerical keypad.
Is HTML copyrighted?
The Copyright Office will not register HTML as a computer program, because HTML does not constitute source code. Source code is typi- cally written by a human being using a computer programming language, such as Java, C, or C++.
What is copyright symbol?
The copyright symbol, or copyright sign, designated by © (a circled capital letter “C”), is the symbol used in copyright notices for works other than sound recordings (which are indicated with the ℗ symbol). The use of the symbol is described in United States law, and, internationally, by the Universal Copyright Convention .
How do you make copyright symbol on Windows?
Use Character Map to insert copyright symbol: Open the Run command box (by pressing Windows+R shortcut key) In the Run box, type charmap and press Enter. Select the copyright symbol from the list given list. Copy the symbol and paste it anywhere you want.
|
__label__pos
| 1 |
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