Using split function in python3.5

Question

Trying to split the string at number 7 and I want 7 to be included in the second part of the split string.

Code:

a = 'cats can jump up to 7 times their tail length'

words = a.split("7")

print(words)

Output:

['cats can jump up to ', ' times their tail length']

String got split but second part doesn't include 7.

I want to know how I can include 7.

note: not a duplicate of Python split() without removing the delimiter because the separator has to be part of the second string.

Answer 1

A simple and naive way to do this is just to find the index of what you want to split on and slice it:

>>> a = 'cats can jump up to 7 times their tail length'
>>> ind = a.index('7')
>>> a[:ind], a[ind:]
('cats can jump up to ', '7 times their tail length')

Answer 2

in one line, using re.split with the rest of the string, and filter the last, empty string that re.split leaves:

import re
a = 'cats can jump up to 7 times their tail length'
print([x for x in re.split("(7.*)",a) if x])

result:

['cats can jump up to ', '7 times their tail length']

using () in split regex tells re.split not to discard the separator. A (7) regex would have worked but would have created a 3-item list like str.partition does, and would have required some post processing, so no one-liner.

now if the number isn't known, regex is (again) the best way to do it. Just change the code to:

[x for x in re.split("(\d.*)",a) if x]