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Date: Thu, 7 Mar 2013 09:27:42 +0000
Subject: iterating over a list as if it were a circular list
From: Sven <svenito@gmail.com>
To: python-list <python-list@python.org>
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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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<div dir=3D"ltr"><div style>Stupid keyboard shortcuts, sent it too early. A=
pologies</div><div style><br></div><div style><br></div><div>I was wonderin=
g what the best approach for the following might be.</div><div><br></div><d=
iv>
Say you have a list P of points and another list N of other items. You can =
always assume that</div><div><br></div><div>len(N) &lt;=3D len(P)</div><div=
><br></div><div>Now I would like to iterate over P and place one N at each =
point. However if you run out of N I&#39;d like to restart from N[0] and ca=
rry on until all the points have been populated.</div>
<div>So far I&#39;ve got (pseudo code)</div><div><br></div><div style>i =3D=
 0</div><div>for point in points:</div><div style>=A0 =A0 put N[i] at point=
</div><div style>=A0 =A0 if i &gt; len(N):</div><div style>=A0 =A0 =A0 =A0 =
i =3D 0</div><div style>
<br></div><div style>is this the most pythonic way to accomplish this?</div=
><div style><br></div><div style>Additionally, what if I wanted to pull a r=
andom element from N, but I want to ensure all elements from N have been us=
ed before starting to pick already chosen random elements again.</div>
<div style>So far I thought of duplicating the list and removing the random=
ly chosen elements from the list, and when it&#39;s empty, re-copying it. B=
ut that seems a little &quot;wrong&quot; if you know what I mean.</div>
<div style><br></div>-- <br>./Sven
</div>

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