great-ai/example/predict_domain.py
András Schmelczer cef2e51c67 Experiment with framework
Signed-off-by: András Schmelczer <andras@schmelczer.dev>
2022-04-02 21:39:58 +02:00

68 lines
2.1 KiB
Python

import re
from typing import Dict, Iterable, List
from config import model_key
from preprocess import preprocess
from models import DomainPrediction
from sklearn.pipeline import Pipeline
from good_ai import use_model
from sus.clean import clean
@use_model(model_key, version="latest")
def predict_domain(
text: str, model: Pipeline, cut_off_probability: float = 0.2
) -> List[DomainPrediction]:
assert 0 <= cut_off_probability <= 1
cleaned = clean(text, convert_to_ascii=True)
text = re.sub(r"[^a-zA-Z0-9]", " ", cleaned)
feature_names = model.named_steps["vectorizer"].get_feature_names_out()
token_mapping = {
preprocess(original): original
for original in text.split(" ")
}
features = model.named_steps["vectorizer"].transform([" ".join(token_mapping.keys())])
prediction = model.named_steps["classifier"].predict_proba(features)[0]
best_classes = sorted(enumerate(prediction), key=lambda v: v[1], reverse=True)
results: List[DomainPrediction] = []
for class_index, probability in best_classes:
weights = model.named_steps["classifier"].feature_log_prob_[class_index]
results.append(
DomainPrediction(
domain=model.named_steps["classifier"].classes_[class_index],
probability=round(probability * 100),
explanation=_get_explanation(
feature_names=feature_names,
features=features.A[0],
weights=weights,
token_mapping=token_mapping,
),
)
)
if sum(r.probability for r in results) >= cut_off_probability:
break
return results
def _get_explanation(
feature_names: Iterable[str],
features: Iterable[float],
weights: Iterable[float],
token_mapping: Dict[str, str],
) -> List[str]:
influential = [
(value * weight, name)
for name, value, weight in zip(feature_names, features, weights)
if value
]
most_influential = sorted(influential, reverse=True)[:5]
return [token_mapping[v[1]] for v in most_influential]