How to pick out a particular group of numbers in a string

December 3, 2021

I have a string (which is different everytime but follows a similar format):

54321.0 67778.0000002 0.3673987009 1 1017.750 88.370 512 7 1 H8711-3040

I’m trying to use regular expressions to be able to pick out any one of those entries in my python code, but I’m struggling.

I’m trying

testRegex = re.compile(r'\w.+\w')
out = testRegex.search('# 53421.0 67778.0000002 0.3673987009 1 1517.750 88.370 512 7 1 J1745-3040')
print(out.group())

But I’m just getting the whole line returned. I can see why it does that but not sure how to just pick out "512" for example (whatever number might be in its place).

>Solution :

You can use

re.findall(r'\b\w(?:\S*\w)?\b', s)

See the regex demo. Details:

\b – a word boundary
\w – a word char
?:\S*\w)? – an optional sequence of any zero or more non-whitespace chars and then a word char
\b – a word boundary

See the Python demo:

import re
s = '# 53421.0 67778.0000002 0.3673987009 1 1517.750 88.370 512 7 1 J1745-3040'
print( re.findall(r'\b\w(?:\S*\w)?\b', s) )
# => ['53421.0', '67778.0000002', '0.3673987009', '1', '1517.750', '88.370', '512', '7', '1', 'J1745-3040']