How to best replace multiple whitespaces by one (in python)?

Question

In python I have, for example, the following string:

a = "Sentence  with     weird    whitespaces"

I want the same string with extended whitespaces replaced by just one, so the final string would read

 'Sentence with weird whitespaces'

I found a solution myself, but is there a better/shorter one?

' '.join([x for x in a.split(' ') if len(x)>0])

have you tried using [`re.sub`](https://docs.python.org/2/library/re.html#re.sub)? — R Nar, May 25 '16 at 18:48
see this link: http://stackoverflow.com/questions/2077897/substitute-multiple-whitespace-with-single-whitespace-in-python — SD433, May 25 '16 at 18:48
If you're looking to make it shorter, you could replace `if len(x).0` with `if x`. Note that this doesn't make it *better*, just shorter. (Code-golf disclaimer) — DJMcMayhem, May 25 '16 at 18:52
Yes sure, I just saw that myself. Adding an empty string is just 'fine' (maybe not from a performance point-of-view, but still) — Alex, May 25 '16 at 18:53

score 34 · Accepted Answer · answered May 25 '16 at 18:48

34

You can use:

import re
a = re.sub(' +',' ',a)

answered May 25 '16 at 18:48

Keiwan

1

I really should use regular expressions more often .... Thanks – Alex May 25 '16 at 18:51
Thank you so much. Would be cool if someone wants to elaborate on the plus sign in that regex as this a perfect example of a situation that calls for it. – Llama D'Attore Oct 26 '20 at 04:31
2

@AlexanderD'Attore + sign above checks for 1 or more consecutive occurrences of a space. – Abhash Upadhyaya Sep 13 '21 at 00:46

score 11 · Answer 2 · answered May 25 '16 at 18:51

11

" ".join(a.split())

pulled this from one of the duplicates for your question

answered May 25 '16 at 18:51

WildCard

Right, I can omit my length check. Adding an empty string to a string does not change string. I really should call it a day... – Alex May 25 '16 at 18:52

score 1 · Answer 3 · answered May 25 '16 at 18:49

Your solution is already very pythonic, I often use a more readable version:

sentence = "Sentence  with     weird    whitespaces"

while "  " in sentence:
    sentence = sentence.replace("  ", " ")

(Replace double spaces by one while double spaces are in string).

Hope this helps!

3 Answers3