Hướng dẫn dùng string.punctuation python

!"#$%&'[]*+, -./:;?@[\]^_`{|}~

Punctuation:,
Punctuation: !
Punctuation:,
Punctuation: ?

Many times while working with Python strings, we have a problem in which we need to remove certain characters from strings. This can have applications in data preprocessing in the Data Science domain and also in day-day programming. Let’s discuss certain ways in which we can perform this task using Python.

Method 1: Remove Punctuation from a String with Translate

The first two arguments for string.translate method is empty strings, and the third input is a Python list of the punctuation that should be removed. This instructs the Python method to eliminate punctuation from a string. This is one of the best ways to strip punctuation from a string.

Python3

import string

test_str = 'Gfg, is best: for ! Geeks ;'

test_str = test_str.translate

    [str.maketrans['', '', string.punctuation]]

print[test_str]

Output:

Gfg is best for  Geeks 

Method 2: Remove Punctuation from a String with Python loop

This is the brute way in which this task can be performed. In this, we check for the punctuations using a raw string that contain punctuations and then we construct a string removing those punctuations.

Python3

test_str = "Gfg, is best : for ! Geeks ;"

print["The original string is : " + test_str]

punc =

for ele in test_str:

    if ele in punc:

        test_str = test_str.replace[ele, ""]

print["The string after punctuation filter : " + test_str]

Output: 

The original string is : Gfg, is best : for ! Geeks ;
The string after punctuation filter : Gfg is best  for  Geeks 

Method 3: Remove Punctuation from a String with regex 

The part of replacing with punctuation can also be performed using regex. In this, we replace all punctuation with an empty string using a certain regex.

Python3

import re

test_str = "Gfg, is best : for ! Geeks ;"

print["The original string is : " + test_str]

res = re.sub[r'[^\w\s]', '', test_str]

print["The string after punctuation filter : " + res]

Output : 

The original string is : Gfg, is best : for ! Geeks ;
The string after punctuation filter : Gfg is best  for  Geeks 

Method 4:  Using for loop, punctuation string and not in operator

Python3

test_str = "Gfg, is best : for ! Geeks ;"

print["The original string is : " + test_str]

punc =

res=" "

for ele in test_str:

    if ele not in punc:

        res+=ele

print["The string after punctuation filter : " + res]

Output

The original string is : Gfg, is best : for ! Geeks ;
The string after punctuation filter :  Gfg is best  for  Geeks 

The Time and Space Complexity for all the methods are the same:

Time Complexity: O[n]

Auxiliary Space: O[n]