tf-idf中文文本分类预处理的python实现,返回值为tf-idf值
时间: 2024-03-25 21:41:14 浏览: 74
好的,下面是tf-idf中文文本分类预处理的Python实现,返回值为tf-idf值:
```python
import math
import jieba
from collections import Counter
def preprocess(documents):
corpus = []
for document in documents:
words = jieba.cut(document)
corpus.append(words)
return corpus
def tf(word, words):
freq = words.count(word)
return freq / len(words)
def idf(word, corpus):
num_documents_containing_word = sum(1 for document in corpus if word in document)
return math.log(len(corpus) / num_documents_containing_word)
def tf_idf(word, words, corpus):
return tf(word, words) * idf(word, corpus)
def get_tfidf(corpus):
tfidf = []
for words in corpus:
document_tfidf = {}
word_counts = Counter(words)
for word, count in word_counts.items():
document_tfidf[word] = tf_idf(word, words, corpus)
tfidf.append(document_tfidf)
return tfidf
```
其中,preprocess函数用于对中文文本进行分词处理,tf函数和idf函数与之前提到的一样,get_tfidf函数用于计算整个文档集合的tf-idf值。使用时,需要传入文档集合,返回值为一个列表,其中每个元素为一个字典,表示对应文档中每个单词的tf-idf值。
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