regex expression to match multiple digits on a single line-CodePudding

Trying to get multiple digits even if its on the same line.

this is what I have so far

import re

lines = '''

1 2

3

4

G3434343 '''

x = re.findall('^\d{1,2}',lines,re.MULTILINE)
print(x)

the output I am getting is:

[1,3,4]

The output I want to get is:

[1,2,3,4]

not sure what to try next any ideas ? Keep in mind the numbers can also be two digits here's another input example

the output for the above should be [8,9,11,15]

CodePudding user response：

You use the ^ which anchors the regex to the beginning of the line. Remove that to find e.g., the "2".

Then you'll also get the "34"s from the "G3434343" which you don't seem to want. So you need to tell the regex that you need to have a word boundary in front and after the digit(s) by using \b. (Adjust this as needed, it's not clear from your examples how you decide which digits you want.)

However, that \b gets interpreted as a backspace, and nothing matches. So you need to change the string to a raw string with a leading 'r' or escape all backslashes with another backslash.

import re

lines = '''

1 2

3

4

G3434343 '''

x = re.findall(r'\b\d{1,2}\b', lines, re.MULTILINE)
print(x)

This prints:

['1', '2', '3', '4']

CodePudding user response：

You can try with lookarounds:

(?<=\s)\d{1,2}(?=\s)

Then map every match of every line to an integer:

[list(map(int, re.findall('(?<=\s)\d{1,2}(?=\s)', line))) for line in lines]

Output:

[[1,2,3,4], [8,9,11,15]]

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