大熊猫read_csv不服从正则表达式月

Question

数据：

from io import StringIO 
import pandas as pd 

s = '''ID,Level,QID,Text,ResponseID,responseText,date_key,last 
375280046,S,D3M,Which is your favorite?,D5M0,option 1,2012-08-08 00:00:00,ynot 
375280046,S,D3M,How often? (at home, at work, other),D3M0,Work,2010-03-31 00:00:00,okkk 
375280046,M,A78,Do you prefer a, b, or c?,A78C,a,2010-03-31 00:00:00,abc 
376918925,M,A78,Which ONE (select only one),A78E,Milk,2004-02-02 00:00:00,launch Wed., ''' 

df = pd.read_csv(StringIO(s), sep=r',(?!\s)') 

问题：我问一个问题here。但我遇到了一个新问题。注意在最后一行的末尾，它是一个逗号和一个空格。 sep=r',(?!\s)'中的正则表达式应该忽略后跟空格的逗号。

问题：有没有办法读的最后一列字面上launch Wed.,，其中逗号不是一个分离器/分隔符，但实际上就是在last列文本逗号 - 只使用pd.read_csv？

错误：

ValueError: Expected 8 fields in line 5, saw 9. Error could possibly be due to quotes being ignored when a multi-char delimiter is used. 

预期/所需的输出：

  ID Level QID         Text ResponseID \ 
0 375280046  S D3M    Which is your favorite?  D5M0 
1 375280046  S D3M How often? (at home, at work, other)  D3M0 
2 375280046  M A78    Do you prefer a, b, or c?  A78C 
3 376918925  M A78   Which ONE (select only one)  A78E 

    responseText    date_key   last 
0  option 1 2012-08-08 00:00:00   ynot 
1   Work 2010-03-31 00:00:00   okkk 
2   a 2010-03-31 00:00:00   abc 
3   Milk 2004-02-02 00:00:00 launch Wed., 

Answer 1

让我们来看看这个SO Post。

使用上面说明的这个正则表达式r',(?=\S)'。

from io import StringIO 
import pandas as pd 

s = '''ID,Level,QID,Text,ResponseID,responseText,date_key,last 
375280046,S,D3M,Which is your favorite?,D5M0,option 1,2012-08-08 00:00:00,ynot 
375280046,S,D3M,How often? (at home, at work, other),D3M0,Work,2010-03-31 00:00:00,okkk 
375280046,M,A78,Do you prefer a, b, or c?,A78C,a,2010-03-31 00:00:00,abc 
376918925,M,A78,Which ONE (select only one),A78E,Milk,2004-02-02 00:00:00,launch Wed., ''' 

df = pd.read_csv(StringIO(s), sep=r',(?=\S)') 

输出：

   ID         Level QID  Text \ 
375280046 S D3M    Which is your favorite? D5M0 option 1 
      S D3M How often? (at home, at work, other) D3M0  Work 
      M A78    Do you prefer a, b, or c? A78C   a 
376918925 M A78   Which ONE (select only one) A78E  Milk 

       ResponseID responseText date_key   last 
375280046 S 2012-08-08 00    0   0   ynot 
      S 2010-03-31 00    0   0   okkk 
      M 2010-03-31 00    0   0   abc 
376918925 M 2004-02-02 00    0   0 launch Wed., 

Answer 2

read_csv出现尝试识别分离器之前被汽提从所述串的端部的空间。这可以通过修改正则表达式来检查在文件结尾之前识别的逗号：

pd.read_csv(StringIO(s), sep=r',(?!\s|\Z)', engine='python') 
Out[347]: 
      ID Level QID         Text ResponseID \ 
0 375280046  S D3M    Which is your favorite?  D5M0 
1 375280046  S D3M How often? (at home, at work, other)  D3M0 
2 375280046  M A78    Do you prefer a, b, or c?  A78C 
3 376918925  M A78   Which ONE (select only one)  A78E 

    responseText    date_key   last 
0  option 1 2012-08-08 00:00:00   ynot 
1   Work 2010-03-31 00:00:00   okkk 
2   a 2010-03-31 00:00:00   abc 
3   Milk 2004-02-02 00:00:00 launch Wed.,