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Start your free trialKeith Ostertag
16,619 PointsUsing lists, why does b = a.sort() not work?
Just playing around, I thought I could do this:
>>> a = [3, 8, 2, 9, 1]
>>> b = a.sort()
>>> b
>>>
What's the rule that makes this invalid?
Of course this works:
>>> b = a
>>> b
[1, 2, 3, 8, 9]
1 Answer
Steven Parker
231,236 PointsThe sort()
method does not return a value.
It just sorts the list that you apply it to. But it doesn't return anything you can assign to another variable.
To do that, you could use sorted
instead:
b = sorted(a)
Keith Ostertag
16,619 PointsKeith Ostertag
16,619 PointsThanks Steven. I was looking at the docs for data structures (https://docs.python.org/3/tutorial/datastructures.html) which doesn't give that detail. Can you tell me where to find that level of detail for list methods?
Steven Parker
231,236 PointsSteven Parker
231,236 PointsYou were in the right place, but on a different page. What you want can be found in the description of
sort
in the list methods[MOD: typo corrections -cf]