Python: Trimming underscores from end of String

Question

Hi everyone! I am trying to debug someones code and I have found the problem. The program loops through an array of strings and count's certain ends. The problem is that some of these strings end with _, so the counting goes wrong. I would like to use regex, but I am not experienced enough. Could someone help me?

I would like to loop through the array and per string check if it ends with _('s) and trim all of these _ off to put them again in the array!

Update

Thanks for the rstrip suggestion! I have tried to write a code that works with my data, but no luck yet...

data_trimmed = []
        for x in data:
            x.rstrip('_')
            data_trimmed.append(x)

        print(data_trimmed)

But this still returns: ['Anna__67_______', 'Dyogo_3__', 'Kiki_P1_', 'BEN_40001__', .... ]

Answer 1

You can use rstrip('_') to remove trailing underscores:

In [15]:
'__as_das___'.rstrip('_')

Out[15]:
'__as_das'

So you can see that any leading underscores and any in the middle of the string are unaffected, see the docs: https://docs.python.org/2/library/string.html#string-functions

To answer your updated question you can use a list comprehension to update each string in the list:

In [18]:
a = ['Anna__67_______', 'Dyogo_3__', 'Kiki_P1_', 'BEN_40001__']
a = [x.rstrip('_') for x in a]
a

Out[18]:
['Anna__67', 'Dyogo_3', 'Kiki_P1', 'BEN_40001']

Answer 2

use string rstrip method to strip off unwanted _

s = 'anything__'
s = s.rstrip('_') # s becomes 'anything'

regex is a bit overkill for this, it can be done as below

import re
s = 'anything__'
s = re.sub('_+$', '', s)  # s becomes 'anything'