Sort tuples based on second parameter

python sorting tuples
user974703 picture user974703 · Dec 10, 2011 · Viewed 101.7k times · Source

I have a list of tuples that look something like this:

("Person 1",10)
("Person 2",8)
("Person 3",12)
("Person 4",20)

What I want produced, is the list sorted in ascending order, by the second value of the tuple. So L[0] should be ("Person 2", 8) after sorting.

How can I do this? Using Python 3.2.2 If that helps.

Answer

Sven Marnach picture Sven Marnach · Dec 10, 2011

You can use the key parameter to list.sort():

my_list.sort(key=lambda x: x[1])

or, slightly faster,

my_list.sort(key=operator.itemgetter(1))

(As with any module, you'll need to import operator to be able to use it.)

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