wcag_AI_validation/scripts/utils.py

36 lines
1.3 KiB
Python

import numpy as np
from transformers import BertTokenizer, BertModel
from sklearn.feature_extraction.text import TfidfVectorizer
import torch
from bert_score import score
def cosine_similarity(a, b):
return np.dot(a, b) / (np.linalg.norm(a) * np.linalg.norm(b))
def semantic_similarity(text1, text2):
tokenizer = BertTokenizer.from_pretrained('bert-base-uncased')
model = BertModel.from_pretrained('bert-base-uncased')
inputs1 = tokenizer(text1, return_tensors='pt')
inputs2 = tokenizer(text2, return_tensors='pt')
with torch.no_grad():
outputs1 = model(**inputs1)
outputs2 = model(**inputs2)
embedding1 = outputs1.last_hidden_state.mean(dim=1).squeeze().numpy()
embedding2 = outputs2.last_hidden_state.mean(dim=1).squeeze().numpy()
return cosine_similarity(embedding1, embedding2)
def lexical_similarity(text1, text2):
vectorizer = TfidfVectorizer(stop_words=None, analyzer='char', ngram_range=(1, 3))
tfidf_matrix = vectorizer.fit_transform([text1, text2])
vec1 = tfidf_matrix.toarray()[0]
vec2 = tfidf_matrix.toarray()[1]
return cosine_similarity(vec1, vec2)
def bert_score_similarity(texts1, texts2):
P, R, F1 = score(texts1, texts2, lang='en', verbose=False, model_type='bert-base-uncased',device=torch.device('cuda' if torch.cuda.is_available() else 'cpu'))
return F1.item()