I would like to group consecutive elements satisfying a predicate. A doctest for such a function would look something like
>>> group([1, 2, 3, 0, 4, 5, 0, 0, 6], lambda x: x != 0)
[[1, 2, 3], [4, 5], [6]]
>>> group([1, 2, 3, 0, 4, 5, 0, 0, 6], lambda x: x == 0)
[[0], [0, 0]]
I have written a prototype where I use itertool's takewhile, but it's ugly because I keep casting between list and iter. I also don't want to stick to reading the indices of a list because it feels inefficient. Can someone point me how to mix and match the itertools together in the right way?
from itertools import takewhile
def group(l, p):
blocks = []
while True:
i = iter(l)
taken = list(takewhile(p, i))
l = list(i)
if len(taken) > 0:
blocks.append(taken)
if len(l) == 0:
return blocks
Thanks!