Isolating parts of String from terminal output

Question

I'm using Python3, Linux Mint and Visual Studio Code.

I have some code that reads a directory and prints some xml files like so:

persistence_security_dcshadow_4742.xml
Network_Service_Guest_added_to_admins_4732.xml
spoolsample_5145.xml
LM_Remote_Service02_7045.xml
DE_RDP_Tunneling_4624.xml

I'm trying to figure out how to write so that only the integers remain after I have run this read script, i.e., removing all text with only numbers remaining. I tried using regular expression with use of the import re module but didn't have much luck.

Answer 1

Use regex with [0-9]

import re

regex = r'[0-9]+'

xmls = [
    'persistence_security_dcshadow_4742.xml',
    'Network_Service_Guest_added_to_admins_4732.xml',
    'spoolsample_5145.xml',
    'LM_Remote_Service02_7045.xml',
    'DE_RDP_Tunneling_4624.xml',
]

for xml in xmls:
    matches = re.findall(regex, xml)
    number = matches[-1]
    print(number)

> 4742
> 4732
> 5145
> 7045
> 4624

UPDATE

If you want to print the numbers only after all the files have been read, then you can create a function that takes a list of xml files and returns the corresponding number for each file

import re

def xmls_to_numbers(xmls):
    regex = r'[0-9]+'
    numbers = [ ]
    for xml in xmls:
        matches = re.findall(regex, xml)
        number = matches[-1]
        numbers.append(number)
    return numbers


xmls = [
    'persistence_security_dcshadow_4742.xml',
    'Network_Service_Guest_added_to_admins_4732.xml',
    'spoolsample_5145.xml',
    'LM_Remote_Service02_7045.xml',
    'DE_RDP_Tunneling_4624.xml',
]

print(xmls_to_numbers(xmls))

> ['4742', '4732', '5145', '7045', '4624']