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[jak]

Il 05/08/2021 11:40, Jach Feng ha scritto:
> I want to distinguish between numbers with/without a dot attached:
> 
>>>> text = 'ch 1. is\nch 23. is\nch 4 is\nch 56 is\n'
>>>> re.compile(r'ch \d{1,}[.]').findall(text)
> ['ch 1.', 'ch 23.']
>>>> re.compile(r'ch \d{1,}[^.]').findall(text)
> ['ch 23', 'ch 4 ', 'ch 56 ']
> 
> I can guess why the 'ch 23' appears in the second list. But how to get rid of it?
> 
> --Jach
> 

import re

t = 'ch 1. is\nch 23. is\nch 4 is\nch 56 is\n'
r = re.compile(r'(ch +\d+\.)|(ch +\d+)', re.M)

res = r.findall(t)

dot = [x[1] for x in res if x[1] != '']
udot = [x[0] for x in res if x[0] != '']

print(f"dot:   {dot}")
print(f"undot: {udot}")

out:

dot:   ['ch 4', 'ch 56']
undot: ['ch 1.', 'ch 23.']