Split a list into parts based on a set of indexes in Python

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This is the simplest and most pythonic solution I can think of:

def partition(alist, indices):
    return [alist[i:j] for i, j in zip([0]+indices, indices+[None])]

if the inputs are very large, then the iterators solution should be more convenient:

from itertools import izip, chain
def partition(alist, indices):
    pairs = izip(chain([0], indices), chain(indices, [None]))
    return (alist[i:j] for i, j in pairs)

and of course, the very, very lazy guy solution (if you don’t mind to get arrays instead of lists, but anyway you can always revert them to lists):

import numpy
partition = numpy.split

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