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Date: Mon, 17 Sep 2012 02:19:58 +1000
Subject: Re: Python presentations
From: Chris Angelico <rosuav@gmail.com>
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Xref: csiph.com comp.lang.python:29332

On Mon, Sep 17, 2012 at 2:13 AM, Alexander Blinne <news@blinne.net> wrote:
> def powerlist3(x,n):
>   return [x**i for i in xrange(n)]
>
> for really big n powerlist3 always takes very much time :)

I would reiterate that a really big n is a really unusual use case for
a function like this, except that... I frankly can't think of *any*
use case for it!! But for many many applications, the simplicity and
readability of a list comp instead of a function is usually going to
outweigh the performance differences.

However, it doesn't surprise me that individually raising a number to
successive powers is slower than iterative multiplication, assuming
you can't massively optimize eg with powers of 2 and bit shifts.

ChrisA