[Tutor] manipulating list of lists

[John Fouhy]

On 25/10/05, Brian van den Broek <broek at cc.umanitoba.ca> wrote:
> To sort by the second item, try
>
>  >>> def sort_by_second(sequence):
>         decorated = [(x[1], x) for x in sequence]
>         decorated.sort()
>         return [x[1] for x in decorated]

With python2.4, you can use the key= argument to sort.

eg:
>>> arr = [('a', 5), ('b', 3), ('c', 7), ('d', 1), ('e', 2)]
>>> arr.sort(key=lambda x: x[1])
>>> arr
[('d', 1), ('e', 2), ('b', 3), ('a', 5), ('c', 7)]

--
John.