app.py

import streamlit as st
import folium
import dask.dataframe as dd
from folium.plugins import MarkerCluster

# Top 10 locations for viewing Northern Lights in Iceland
northern_lights_locations = [
    {"name": "Reykjavik", "lat": 64.1265, "lon": -21.8174},
    {"name": "Akureyri", "lat": 65.6885, "lon": -18.1262},
    {"name": "Vik", "lat": 63.4194, "lon": -19.0096},
    {"name": "Hofn", "lat": 64.2539, "lon": -15.2082},
    {"name": "Husavik", "lat": 66.0449, "lon": -17.3382},
    {"name": "Grundarfjordur", "lat": 64.9226, "lon": -23.2543},
    {"name": "Egilsstadir", "lat": 65.2669, "lon": -14.3948},
    {"name": "Seydisfjordur", "lat": 65.2592, "lon": -14.0101},
    {"name": "Isafjordur", "lat": 66.0750, "lon": -23.1266},
    {"name": "Kirkjufell", "lat": 64.9426, "lon": -23.3061},
]

# Function to display the map
def display_map(locations, lat, lon):
    # Create a folium map centered in Iceland
    iceland_map = folium.Map(location=[lat, lon], zoom_start=6)

    # Create a marker cluster group
    marker_cluster = MarkerCluster().add_to(iceland_map)

    # Create a Dask dataframe from the list of locations
    dask_df = dd.from_pandas(pd.DataFrame(locations), npartitions=4)

    # Add markers for the top 10 locations for viewing Northern Lights
    def add_markers(row):
        folium.Marker(
            location=[row["lat"], row["lon"]],
            popup=f"<b>{row['name']}</b>",
        ).add_to(marker_cluster)

    dask_df.map_partitions(lambda df: df.apply(add_markers, axis=1)).compute()

    return iceland_map

# Streamlit app
st.title("Northern Lights Map in Iceland")

# User input for latitude and longitude
lat = st.number_input("Enter latitude:", value=64.9631, step=0.0001)
lon = st.number_input("Enter longitude:", value=-19.0208, step=0.0001)

# Display the map
st.write("Northern Lights Viewing Locations in Iceland:")
folium_map = display_map(northern_lights_locations, lat, lon)
st.folium_static(folium_map)

# Cite references
st.write(
    """
    References:
    - [Folium documentation](https://python-visualization.github.io/folium/)
    - [Streamlit documentation](https://docs.streamlit.io/)
    - [Dask documentation](https://dask.org/)
    - [Top 10 locations](https://www.guidetoiceland.is/best-of-iceland/top-10-places-to-see-the-northern-lights)
"""
)