3.8. index_humansorted()

natsort.index_humansorted(seq, key=None, reverse=False, alg=0)

Return the list of the indexes used to sort the input sequence in a locale-aware manner.

Sorts a sequence in a locale-aware manner, but returns a list of sorted the indexes and not the sorted list. This list of indexes can be used to sort multiple lists by the sorted order of the given sequence.

This is a wrapper around index_natsorted(seq, alg=ns.LOCALE).

Parameters:

seq: iterable

The sequence to sort.

key: callable, optional

A key used to determine how to sort each element of the sequence. It is not applied recursively. It should accept a single argument and return a single value.

reverse : {True, False}, optional

Return the list in reversed sorted order. The default is False.

alg : ns enum, optional

This option is used to control which algorithm natsort uses when sorting. For details into these options, please see the ns class documentation. The default is ns.FLOAT.

Returns:

out : tuple

The ordered indexes of the sequence.

Notes

You may find that if you do not explicitly set the locale your results may not be as you expect... I have found that it depends on the system you are on. To do this is straightforward (in the below example I use ‘en_US.UTF-8’, but you should use your locale):

>>> import locale
>>> # The 'str' call is only to get around a bug on Python 2.x
>>> # where 'setlocale' does not expect unicode strings (ironic,
>>> # right?)
>>> locale.setlocale(locale.LC_ALL, str('en_US.UTF-8'))
'en_US.UTF-8'

It is preferred that you do this before importing natsort. If you use PyICU (see warning above) then you should not need to do this.

Examples

Use index_humansorted just like the builtin sorted:

>>> a = ['Apple', 'Banana', 'apple', 'banana']
>>> index_humansorted(a)
[2, 0, 3, 1]