预处理 pandas 数据框中的字符串数据

Preprocessing string data in pandas dataframe

我有一个用户评论数据集。我已经加载了这个数据集,现在我想预处理用户评论(即删除停用词、标点符号、转换为小写、删除称呼等),然后再将其放入分类器,但出现错误。这是我的代码:

    import pandas as pd
    import numpy as np
    df=pd.read_json("C:/Users/ABC/Downloads/Compressed/reviews_Musical_Instruments_5.json/Musical_Instruments_5.json",lines=True)
    dataset=df.filter(['overall','reviewText'],axis=1)
    def cleanText(text):
        """
        removes punctuation, stopwords and returns lowercase text in a list 
        of single words
        """
        text = (text.lower() for text in text)   

        from bs4 import BeautifulSoup
        text = BeautifulSoup(text).get_text()

        from nltk.tokenize import RegexpTokenizer
        tokenizer = RegexpTokenizer(r'\w+')
        text = tokenizer.tokenize(text)

        from nltk.corpus import stopwords
        clean = [word for word in text if word not in 
        stopwords.words('english')]

        return clean

    dataset['reviewText']=dataset['reviewText'].apply(cleanText)
    dataset['reviewText']

我收到这些错误:

TypeError                                 Traceback (most recent call last)
<ipython-input-68-f42f70ec46e5> in <module>()
----> 1 dataset['reviewText']=dataset['reviewText'].apply(cleanText)
      2 dataset['reviewText']

~\Anaconda3\lib\site-packages\pandas\core\series.py in apply(self, func, convert_dtype, args, **kwds)
   2353             else:
   2354                 values = self.asobject
-> 2355                 mapped = lib.map_infer(values, f, convert=convert_dtype)
   2356 
   2357         if len(mapped) and isinstance(mapped[0], Series):

pandas/_libs/src\inference.pyx in pandas._libs.lib.map_infer()

<ipython-input-64-5c6792de405c> in cleanText(text)
     10     from nltk.tokenize import RegexpTokenizer
     11     tokenizer = RegexpTokenizer(r'\w+')
---> 12     text = tokenizer.tokenize(text)
     13 
     14     from nltk.corpus import stopwords

~\Anaconda3\lib\site-packages\nltk\tokenize\regexp.py in tokenize(self, text)
    127         # If our regexp matches tokens, use re.findall:
    128         else:
--> 129             return self._regexp.findall(text)
    130 
    131     def span_tokenize(self, text):

TypeError: expected string or bytes-like object

TypeError                                 Traceback (most recent call last)
<ipython-input-70-f42f70ec46e5> in <module>()
----> 1 dataset['reviewText']=dataset['reviewText'].apply(cleanText)
      2 dataset['reviewText']

~\Anaconda3\lib\site-packages\pandas\core\series.py in apply(self, func, convert_dtype, args, **kwds)
   2353             else:
   2354                 values = self.asobject
-> 2355                 mapped = lib.map_infer(values, f, convert=convert_dtype)
   2356 
   2357         if len(mapped) and isinstance(mapped[0], Series):

pandas/_libs/src\inference.pyx in pandas._libs.lib.map_infer()

<ipython-input-69-5c6792de405c> in cleanText(text)
     10     from nltk.tokenize import RegexpTokenizer
     11     tokenizer = RegexpTokenizer(r'\w+')
---> 12     text = tokenizer.tokenize(text)
     13 
     14     from nltk.corpus import stopwords

~\Anaconda3\lib\site-packages\nltk\tokenize\regexp.py in tokenize(self, text)
    127         # If our regexp matches tokens, use re.findall:
    128         else:
--> 129             return self._regexp.findall(text)
    130 
    131     def span_tokenize(self, text):

TypeError: expected string or bytes-like object

请在此函数中为我的数据提出更正建议或提出新的数据清理函数。

这是我的数据:

    overall reviewText
0   5   Not much to write about here, but it does exac...
1   5   The product does exactly as it should and is q...
2   5   The primary job of this device is to block the...
3   5   Nice windscreen protects my MXL mic and preven...
4   5   This pop filter is great. It looks and perform...
5   5   So good that I bought another one. Love the h...
6   5   I have used monster cables for years, and with...
7   3   I now use this cable to run from the output of...
8   5   Perfect for my Epiphone Sheraton II. Monster ...
9   5   Monster makes the best cables and a lifetime w...
10  5   Monster makes a wide array of cables, includin...
11  4   I got it to have it if I needed it. I have fou...
12  3   If you are not use to using a large sustaining...
13  5   I love it, I used this for my Yamaha ypt-230 a...
14  5   I bought this to use in my home studio to cont...
15  2   I bought this to use with my keyboard. I wasn'...

打印(df)

    overall reviewText
0   5   Not much to write about here, but it does exac...
1   5   The product does exactly as it should and is q...
2   5   The primary job of this device is to block the...
3   5   Nice windscreen protects my MXL mic and preven...
4   5   This pop filter is great. It looks and perform...
5   5   So good that I bought another one. Love the h...
6   5   I have used monster cables for years, and with...
7   3   I now use this cable to run from the output of...
8   5   Perfect for my Epiphone Sheraton II. Monster ...
9   5   Monster makes the best cables and a lifetime w...
10  5   Monster makes a wide array of cables, includin...
11  4   I got it to have it if I needed it. I have fou...
12  3   If you are not use to using a large sustaining...
13  5   I love it, I used this for my Yamaha ypt-230 a...
14  5   I bought this to use in my home studio to cont...
15  2   I bought this to use with my keyboard. I wasn'...

转换成小写

df.loc[:,"reviewText"] = df.reviewText.apply(lambda x : str.lower(x))

删除标点符号和数字

import re
df.loc[:,"reviewText"] = df.reviewText.apply(lambda x : " ".join(re.findall('[\w]+',x)))

要删除停用词,您可以安装停用词或创建自己的停用词列表并将其与函数一起使用

from stop_words import get_stop_words
stop_words = get_stop_words('en')

def remove_stopWords(s):
    '''For removing stop words
    '''
    s = ' '.join(word for word in s.split() if word not in stop_words)
    return s

df.loc[:,"reviewText"] = df.reviewText.apply(lambda x: remove_stopWords(x))