How to remove punctuation marks from a string in Python 3.x using .translate()?

Question

I want to remove all punctuation marks from a text file using .translate() method. It seems to work well under Python 2.x but under Python 3.4 it doesn\'t seem to do anythin

Answer 1

Late answer, but to remove all punctuation on python >= 3.6, you can also use:

import re, string

clean_string = re.sub(rf"[{string.punctuation}]", "", dirty_string)

Demo

Answer 2

The call signature of str.translate has changed and apparently the parameter deletechars has been removed. You could use

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

instead, or create a table as shown in the other answer.

Answer 3

You have to create a translation table using maketrans that you pass to the str.translate method.

In Python 3.1 and newer, maketrans is now a static-method on the str type, so you can use it to create a translation of each punctuation you want to 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))

This should output:

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

Answer 4

I just compared the three methods by speed. translate is slower than re.sub (with precomilation) in about 10 times. And str.replace is faster than re.sub in about 3 times. By str.replace I mean:

for ch in string.punctuation:                                                                                                     
    s = s.replace(ch, "'") 

Answer 5

In python3.x ,it can be done using :

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