Python | Extract digits from given string

While programming, sometimes, we just require a certain type of data and need to discard other. This type of problem is quite common in Data Science domain, and since Data Science uses Python worldwide, its important to know how to extract specific elements. This article discusses certain ways in which only digit can be extracted. Let’s discuss the same.

Method #1 : Using join() + isdigit() + filter()

This task can be performed using the combination of above functions. The filter function filters the digits detected by the isdigit function and join function performs the task of reconstruction of join function.

filter_none

edit
close

play_arrow

link
brightness_4
code

# Python3 code to demonstrate
# Extract digit string 
# using join() + isdigit() + filter()
  
# initializing string
test_string = 'g1eeks4geeks5'
  
# printing original strings  
print("The original string : " + test_string)
  
# using join() + isdigit() + filter()
# Extract digit string 
res = ''.join(filter(lambda i: i.isdigit(), test_string))
      
# print result
print("The digits string is : " + str(res))

chevron_right


Output :

The original string : g1eeks4geeks5
The digits string is : 145

 

Method #2 : Using re
The regular expressions can also be used to perform this particular task. We can define the digit type requirement, using “\D”, and only digits are extracted from the string.

filter_none

edit
close

play_arrow

link
brightness_4
code

# Python3 code to demonstrate
# Extract digit string 
# using re
import re
  
# initializing string
test_string = 'g1eeks4geeks5'
  
# printing original strings  
print("The original string : " + test_string)
  
# using re
# Extract digit string 
res = re.sub("\D", "", test_string)
      
# print result
print("The digits string is : " + str(res))

chevron_right


Output :

The original string : g1eeks4geeks5
The digits string is : 145


My Personal Notes arrow_drop_up

Check out this Author's contributed articles.

If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.




Article Tags :

Be the First to upvote.


Please write to us at contribute@geeksforgeeks.org to report any issue with the above content.