open:无效模式或文件名

Question

这是单词计数程序。怎么能让它变得更简单呢？

import re
from collections import Counter
with open('C:Datatest.txt') as f:
passage = f.read()
words = re.findall(r'w+', passage)
cap_words = [word.upper() for word in words]
word_counts = Counter(cap_words)

不断得到这个错误消息：

Traceback (most recent call last):
File "C:/Python27/wordcount", line 4, in <module>
with open('C:Datatest.txt') as f:
IOError: [Errno 22] invalid mode ('r') or filename: 'C:\Datatest.txt'

Answer 1

使用原始字符串或用转义每个。这是必需的，因为如果没有它，'t'将被转换为选项卡空间：

r'C:Datatest.txt'

示例：

>>> print 'C:Datatest.txt'
C:Data est.txt                 #t is converted to tab
>>> print r'C:Datatest.txt'   
C:Datatest.txt                #here it is fine
>>> print 'C:\Data\test.txt'  #same as raw string, but manual escaping
C:Datatest.txt