如何使用.translate()从Python 3.x中的字符串中删除标点符号？

Question

我想使用.translate()方法从文本文件中删除所有标点符号.它似乎在Python 2.x下运行良好,但在Python 3.4下似乎没有做任何事情.

我的代码如下,输出与输入文本相同.

import string
fhand = open("Hemingway.txt")
for fline in fhand:
    fline = fline.rstrip()
    print(fline.translate(string.punctuation))

Answer 1

您必须使用maketrans传递给str.translate方法的转换表创建转换表.

在Python 3.1及更新版本中,maketrans现在是该str类型的静态方法,因此您可以使用它来创建您想要的每个标点符号的翻译None.

import string

# Thanks to Martijn Pieters for this improved version

# This uses the 3-argument version of str.maketrans
# with arguments (x, y, z) where 'x' and 'y'
# must be equal-length strings and characters in 'x'
# are replaced by characters in 'y'. 'z'
# is a string (string.punctuation here)
# where each character in the string is mapped
# to None
translator = str.maketrans('', '', string.punctuation)

# This is an alternative that creates a dictionary mapping
# of every character from string.punctuation to None (this will
# also work)
#translator = str.maketrans(dict.fromkeys(string.punctuation))

s = 'string with "punctuation" inside of it! Does this work? I hope so.'

# pass the translator to the string's translate method.
print(s.translate(translator))

这应输出:

string with punctuation inside of it Does this work I hope so

Answer 2

在python3.x中,可以使用以下命令完成:

import string
#make translator object
translator=str.maketrans('','',string.punctuation)
string_name=string_name.translate(translator)

Answer 3

str.translate的调用签名已更改,显然已删除参数deletechars.你可以用

import re
fline = re.sub('['+string.punctuation+']', '', fline)

相反,或创建一个表,如另一个答案所示.