how to sort tuple in python?

Question

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Sorting a tuple that contains tuples

I am having some trouble with sorting a tuple which contain number and string. in the beginning, I have a tuple like this:

a=(("a",2),("b",2),("a",1))

then how can I sort it into: (by number first then alphabetical)

a=(("a",1),("a",2),("b",2))

Thank a lot for your help!

Definitly a duplicate. And man, that's the first 5 entries in Google for "sort tuple". — Bite code, Dec 03 '11 at 17:51

vasek1 · Answer 1 · 2011-12-03T18:09:26.063

3

Tuples cannot be sorted by definition because they are immutable. You can convert this to a list, sort the list, and then convert back to tuple. Something like this,

mylist = sorted(a, key = lambda x: str(x[1])+str(x[0]))
a = tuple(mylist)

edited Dec 03 '11 at 18:09

answered Dec 03 '11 at 17:49

vasek1

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Sorted converts it to a list automatically. No need to do list(a) first. – U-DON Dec 03 '11 at 17:51
Didn't know that, but will keep in mind from now on. Thanks! – vasek1 Dec 03 '11 at 18:08

score 3 · Accepted Answer · edited Dec 03 '11 at 18:12

3

>>> a=(("a",2),("b",2),("a",1))
>>> from operator import itemgetter
>>> sorted(a, key=itemgetter(1, 0))
[('a', 1), ('a', 2), ('b', 2)]

edited Dec 03 '11 at 18:12

Petr Viktorin

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answered Dec 03 '11 at 17:51

setrofim

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Did you know you can use `itemgetter(1, 0)` to get two items at once? No need to call `sorted` twice. – Petr Viktorin Dec 03 '11 at 17:54
Nope, didn't know that one. Thanks for that. – setrofim Dec 03 '11 at 18:02
It's worth mentioning that this returns a list while the question specifically wants a tuple as the output. Sometimes this can matter. – AnnanFay Nov 19 '19 at 18:20

score 1 · Answer 3 · answered Dec 03 '11 at 17:48

1

The built-in function sorted will do that for you.

answered Dec 03 '11 at 17:48

Bite code

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how to sort tuple in python?

3 Answers3