pythonic way of selecing a random value that satisfies a certain predicate

Posted by MK on Stack Overflow See other posts from Stack Overflow or by MK
Published on 2010-05-14T16:18:17Z Indexed on 2010/05/14 16:24 UTC
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pythonic

Suppose I have a list of elements and I want to randomly select an element from the list that satisfies a predicate. What is the pythonic way of doing this?

I currently do a comprehension followed by a random.choice() but that is unnecessarily inefficient :

intlist = [1,2,3,4,5,6,7,8,9]
evenlist = [ i for i in intlist if i % 2 == 0 ] 
randomeven = random.choice(evenlist)

Thanks!

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