def test_extract_window(self):
sen_str = 'this is a test sentence.'
sen = word_tokenize(sen_str.lower())
test_token = 'this'
window = ngram_window_extractor.extract_window(sen, test_token)
self.assertListEqual(window, ['_START_', 'this', 'is'], 'A window starting with the first token should be correct')
sen2_str = 'this is a test sentence.'
sen2 = word_tokenize(sen2_str.lower())
test_token2 = 'is'
window2 = ngram_window_extractor.extract_window(sen2, test_token2)
self.assertListEqual(window2, ['this', 'is', 'a'], 'A window starting with the second token should be correct')
def get_features(self, context_obj):
idx = context_obj['index']
left_ngram = left_context(context_obj['target'], context_obj['token'], context_size=self.order-1, idx=idx) + [context_obj['token']]
right_ngram = [context_obj['token']] + right_context(context_obj['target'], context_obj['token'], context_size=self.order-1, idx=idx)
left_ngram_order = self.check_lm(left_ngram, side='left')
right_ngram_order = self.check_lm(right_ngram, side='right')
left_trigram = left_context(context_obj['target'], context_obj['token'], context_size=2, idx=idx) + [context_obj['token']]
middle_trigram = extract_window(context_obj['target'], context_obj['token'], idx=idx)
right_trigram = [context_obj['token']] + right_context(context_obj['target'], context_obj['token'], context_size=2, idx=idx)
backoff_left = self.get_backoff(left_trigram)
backoff_middle = self.get_backoff(middle_trigram)
backoff_right = self.get_backoff(right_trigram)
return [left_ngram_order, right_ngram_order, backoff_left, backoff_middle, backoff_right]
def get_features(self, context_obj):
idx = context_obj['index']
left_ngram = left_context(context_obj['target'],
context_obj['token'],
context_size=self.order - 1,
idx=idx) + [context_obj['token']]
right_ngram = [context_obj['token']] + right_context(
context_obj['target'],
context_obj['token'],
context_size=self.order - 1,
idx=idx)
left_ngram_order = self.check_lm(left_ngram, side='left')
right_ngram_order = self.check_lm(right_ngram, side='right')
left_trigram = left_context(context_obj['target'],
context_obj['token'],
context_size=2,
idx=idx) + [context_obj['token']]
middle_trigram = extract_window(context_obj['target'],
context_obj['token'],
idx=idx)
right_trigram = [context_obj['token']] + right_context(
context_obj['target'],
context_obj['token'],
context_size=2,
idx=idx)
# TODO: instead of _START_ there should be <s>
backoff_left = self.get_backoff(left_trigram)
backoff_middle = self.get_backoff(middle_trigram)
backoff_right = self.get_backoff(right_trigram)
return [
left_ngram_order, right_ngram_order, backoff_left, backoff_middle,
backoff_right
]