Remove an element from a str

Question

I have a list in which I add elements like this:

listA.append('{:<30s} {:>10s}'.format(element, str(code)))

so listA looks like this:

Paris          75
Amsterdam      120
New York City  444 
L.A            845

I would like, now from this listA, to add elements to a "listB" list, without the code. I would like to do this:

for i in listA:
    listB.append(i - str(code))   #that's what i want to do. The code is not good

and I want the listB to look like this:

    Paris
    Amsterdam 
    New York City
    L.A

and only using listA and without having access to 'element' and 'code'

Can someone can help me ?

You're not using `i` in the second loop at all. Where is `element` and `code` coming from? — Milan Cermak, Jun 16 '20 at 08:13
It sounds like you're probably looking for this: [How to remove specific substrings...in Python](https://stackoverflow.com/a/37372690) — asdf, Jun 16 '20 at 08:15
Not sure I fully understand you, but why don't you build listB right after you build listA, something like - listB.append(element)? — LemonPy, Jun 16 '20 at 08:16
@IftahP because it's just an example. in my project I no longer have access to 'element' and 'code'. I just have access to the list A already made — Isoka05m, Jun 16 '20 at 08:18

score 2 · Accepted Answer · answered Jun 16 '20 at 08:19

2

You can use regex for that

import re

for i in listA:
    listB.append(re.sub(r"\W+\d+", "", i))

This will remove the code that is numbers and the spaces before it.

answered Jun 16 '20 at 08:19

Leo Arad

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score 1 · Answer 2 · answered Jun 16 '20 at 08:19

1

Try this:

import re
listB = [re.sub('\d+', '', x).strip() for x in listA]
print(listB)

Output:

['Paris', 'Amsterdam', 'New York City', 'L.A']

answered Jun 16 '20 at 08:19

deadshot

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score 0 · Answer 3 · answered Jun 16 '20 at 08:20

0

This seems to work for me

listB=[]
for i in listA:
    listB.append(listA[0][:len(element)])
print(listB)

answered Jun 16 '20 at 08:20

maria_g

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Deerenaros · Answer 4 · 2020-06-16T08:30:43.160

How about to use re.sub? And instead of using for in it would be better to map functional style or [for in] list comprehension:

import re
listB = list(map(lambda x: re.sub(r"\s+\d+", "", x), listA))

or, even better

import re
listB = [re.sub(r"\s+\d+", "", x) for x in listA]

A little about regex:

re.sub - is a function what searches an removes all occurrences of first argument to second in third one
r"\s+\d+" - is a 'raw' string literal with regex inside
\s+ - one or more whitespaces (\t\n\r etc)
\d+ - one or more digits (\d is an allias for [0-9])
For more information about regex use this documentation page

score 0 · Answer 5 · edited Jun 16 '20 at 11:54

0

Easiest way without any new libraries.

You can create a variable with 40 spaces(because of 40 spaces in the format clause). eg: space_var = " " Then use the following code to extract element from listA:

listB=[]
for i in listA:
    listB.append(listA[0].rsplit(space_var,1)[0])

edited Jun 16 '20 at 11:54

DavideBrex

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answered Jun 16 '20 at 08:27

chohan kumar

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score 0 · Answer 6 · answered Jun 16 '20 at 08:28

You can try the following:

listB = [element.rsplit(' ', maxsplit=1)[0].rstrip() for element in listA]

rsplit(' ', maxsplit=1) means you will split the element of listA once at first space from the right side. Additional rstrip() will get rid of the other spaces from the right side.

Remove an element from a str

6 Answers6