If I have a the list
listOfFiles = [<str>,<intA>,<intB>]
How can I sort this list first by intA then by intB?
The end result would look like
<str>,1,1
<str>,1,2
<str>,1,3
<str>,2,1
<str>,2,2
etc
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3 Answers
Use a compound key (or rather, a sequence as a key).
listOfFiles.sort(key=operator.itemgetter(1, 2))
answered Apr 14, 2011 at 18:36
Ignacio Vazquez-Abrams
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1 Comment
Daniel Roseman
Wow, didn't know that you could pass multiple arguments to
operator.itemgetter.Python list sorting is done in place and is guaranteed to be stable after 2.4 (I believe, it may have been 2.5). That means you can sort like so and should get the results you want:
listOfFiles.sort(key = lambda x: x[2])
listOfFiles.sort(key = lambda x: x[1])
I presume you actually have a list of lists, or a list of tuples. If not, please provide a more complete example of your data structure.
1 Comment
recursive
I would just make the lambda x[1], x[2] so you only need to sort once.
This also works:
listOfFiles.sort(key=lambda x: (x[1], x[2]))
