Python：檢查句子中是否包含列表中的任何單詞（模糊匹配）

Question

我想從給定list_of_keywords的句子中提取關鍵字。

我設法提取出確切的單詞

[word for word in Sentence if word in set(list_of_keywords)]

是否可以提取與給定list_of_keywords具有良好相似性的單詞，即兩個單詞之間的余弦相似度> 0.8

例如，給定列表中的關鍵字為“過敏”，現在該句子寫為

她對進餐后的堅果產生了嚴重的過敏反應。

“過敏”和“過敏”之間的余弦距離可計算如下

cosdis(word2vec('allergy'), word2vec('allergic'))
Out[861]: 0.8432740427115677

如何基於余弦相似度從句子中提取“過敏”？

Answer 1

def word2vec(word):
    from collections import Counter
    from math import sqrt

    # count the characters in word
    cw = Counter(word)
    # precomputes a set of the different characters
    sw = set(cw)
    # precomputes the "length" of the word vector
    lw = sqrt(sum(c*c for c in cw.values()))

    # return a tuple
    return cw, sw, lw

def cosdis(v1, v2):
    # which characters are common to the two words?
    common = v1[1].intersection(v2[1])
    # by definition of cosine distance we have
    return sum(v1[0][ch]*v2[0][ch] for ch in common)/v1[2]/v2[2]


list_of_keywords = ['allergy', 'something']
Sentence = 'a severe allergic reaction to nuts in the meal she had consumed.'

threshold = 0.80
for key in list_of_keywords:
    for word in Sentence.split():
        try:
            # print(key)
            # print(word)
            res = cosdis(word2vec(word), word2vec(key))
            # print(res)
            if res > threshold:
                print("Found a word with cosine distance > 80 : {} with original word: {}".format(word, key))
        except IndexError:
            pass

輸出 ：

Found a word with cosine distance > 80 : allergic with original word: allergy

編輯 ：

一線殺手：

print([x for x in Sentence.split() for y in list_of_keywords if cosdis(word2vec(x), word2vec(y)) > 0.8])

輸出 ：

['allergic']

Answer 2

單詞的距離必須對照所有關鍵字進行檢查，並且僅在達到任何關鍵字的閾值時才包括在內。 我在原始列表理解中添加了一個額外的條件，而嵌套列表理解正是這樣做的。

def distance(words):
    return cosdis(word2vec(words[0]), word2vec(words[1]))

threshold = 0.8
keywords = set(list_of_keywords)
matches = [word for word in Sentence if word in keywords and 
           any([distance(word, keyword) > threshold for keyword in keywords])]

Answer 3

senectence = 'a severe allergic reaction to nuts in the meal she had consumed.'
list_of_keywords = ['allergy','reaction']
word_list = []
for keyword in list_of_keywords:
    for word in senectence.split():
        if(cosdis(word2vec(keyword), word2vec(word)) > 0.8):
            word_list.append(word)

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或者如果您只想提取基於“過敏”關鍵字的單詞

[word for word in Sentence if cosdis(word2vec('allergy'), word2vec(word)) > 0.8]