python equivalent to php natcasesort

Question

Possible Duplicate:
Does Python have a built in function for string natural sort?

Is there a function in python equivalent to php's natcasesort()?

http://php.net/manual/en/function.natcasesort.php

See: http://stackoverflow.com/questions/4836710/does-python-have-a-built-in-function-for-string-natural-sort http://stackoverflow.com/questions/2545532/python-analog-of-natsort-function-sort-a-list-using-a-natural-order-algorithm — Lack, Jan 04 '13 at 18:36
Yes, this is an exact dup, and the first question has perfectly reasonable answers—complete working implementations, links to additional information. — abarnert, Jan 04 '13 at 18:44
@Quamis Python 2 has lambdas. http://docs.python.org/2/reference/expressions.html#lambda — Lack, Jan 04 '13 at 18:54
@Quamis: Actually, `lambdas` are a feature Guido _thought about removing_ in python3, but fortunately everyone else talked him out of it. — abarnert, Jan 04 '13 at 20:01

score 3 · Accepted Answer · answered Jan 04 '13 at 18:37

import re

def atoi(text):
    return int(text) if text.isdigit() else text.lower()

def natural_keys(text):
    '''
    alist.sort(key=natural_keys) sorts in human order
    http://nedbatchelder.com/blog/200712/human_sorting.html
    (See Toothy's implementation in the comments)
    '''    
    return [ atoi(c) for c in re.split('(\d+)', text) ]

names = ('IMG0.png', 'img12.png', 'img10.png', 'img2.png', 'img1.png', 'IMG3.png')

Standard sorting:

print(sorted(names))
# ['IMG0.png', 'IMG3.png', 'img1.png', 'img10.png', 'img12.png', 'img2.png']

Natural order sorting (case-insensitive):

print(sorted(names, key = natural_keys))
# ['IMG0.png', 'img1.png', 'img2.png', 'IMG3.png', 'img10.png', 'img12.png']

python equivalent to php natcasesort

1 Answers1