File size: 3,960 Bytes
d94d830 |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 |
class ContextSampler:
def __init__(self, docs, task, fewshot_indices=None, rnd=None) -> None:
self.rnd = rnd
assert self.rnd, "must pass rnd to FewShotSampler!"
self.task = task
self.config = task._config
self.target_delimiter = self.config.target_delimiter
self.fewshot_delimiter = self.config.fewshot_delimiter
self.doc_to_text = self.task.doc_to_text
self.doc_to_target = self.task.doc_to_target
self.doc_to_choice = self.task.doc_to_choice
self.docs = docs # HF dataset split, provided by task._fewshot_docs()
if fewshot_indices: # subset few-shot docs from
self.docs = self.docs.select(fewshot_indices)
def get_context(self, doc, num_fewshot):
# draw an extra fewshot sample if using same split as evaluating on
n_samples = (
num_fewshot + 1
if self.config.fewshot_split == self.config.test_split
else num_fewshot
)
# draw `n_samples` docs from fewshot_docs
fewshotex = self.sample(n_samples)
# get rid of the doc that's the one we're evaluating, if it's in the fewshot
# TODO: should we just stop people from using fewshot from same split as evaluating?
selected_docs = [x for x in fewshotex if x != doc][:num_fewshot]
labeled_examples = (
self.fewshot_delimiter.join(
[
# TODO: is separating doc_to_text and doc_to_target by one space always desired?
(
self.doc_to_text(doc)
if (
self.config.doc_to_choice is None
or isinstance(self.doc_to_text(doc), str)
)
else self.doc_to_choice(doc)[self.doc_to_text(doc)]
)
+ self.target_delimiter
+ (
str(self.doc_to_target(doc)[0])
if isinstance(self.doc_to_target(doc), list)
else self.doc_to_target(doc)
if (
self.config.doc_to_choice is None
or isinstance(self.doc_to_target(doc), str)
)
else str(self.doc_to_choice(doc)[self.doc_to_target(doc)])
)
for doc in selected_docs
]
)
+ self.fewshot_delimiter
)
return labeled_examples
def sample(self, n):
"""
Draw `n` samples from our fewshot docs. This method should be overridden by subclasses.
"""
return self.rnd.sample(self.docs, n)
class FirstNSampler(ContextSampler):
def sample(self, n) -> None:
"""
Draw the first `n` samples in order from the specified split.
Used for tasks with "canonical" ordered fewshot examples, such as MMLU and CMMLU.
"""
assert (
n <= len(self.docs)
), f"Error: number of fewshot samples requested exceeds the {len(self.docs)} that are available."
return self.docs[:n]
class BalancedSampler(ContextSampler):
def sample(self, n) -> None:
"""
TODO: this should return approximately class-balanced samples from our fewshot examples.
TODO: what order should they be in? maybe random?
"""
pass
class ManualSampler(ContextSampler):
def sample(self, n) -> None:
""" """
pass
SAMPLER_REGISTRY = {
"default": ContextSampler,
"first_n": FirstNSampler,
}
def get_sampler(name):
try:
return SAMPLER_REGISTRY[name]
except KeyError:
raise ValueError(
f"Attempted to use contextsampler '{name}', but no sampling strategy for this name found! Supported model names: {', '.join(SAMPLER_REGISTRY.keys())}"
)
|