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iterating over a list as if it were a circular list

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Stupid keyboard shortcuts, sent it too early. Apologies


I was wondering what the best approach for the following might be.

Say you have a list P of points and another list N of other items. You can
always assume that

len(N) <= len(P)

Now I would like to iterate over P and place one N at each point. However
if you run out of N I'd like to restart from N[0] and carry on until all
the points have been populated.
So far I've got (pseudo code)

i = 0
for point in points:
    put N[i] at point
    if i > len(N):
        i = 0

is this the most pythonic way to accomplish this?

Additionally, what if I wanted to pull a random element from N, but I want
to ensure all elements from N have been used before starting to pick
already chosen random elements again.
So far I thought of duplicating the list and removing the randomly chosen
elements from the list, and when it's empty, re-copying it. But that seems
a little "wrong" if you know what I mean.

-- 
./Sven

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Thread

iterating over a list as if it were a circular list Sven <svenito@gmail.com> - 2013-03-07 09:27 +0000
  Re: iterating over a list as if it were a circular list Alexander Blinne <news@blinne.net> - 2013-03-08 00:49 +0100
    Re: iterating over a list as if it were a circular list Alexander Blinne <news@blinne.net> - 2013-03-08 00:50 +0100
  Re: iterating over a list as if it were a circular list Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-03-08 17:59 +0000

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