Re: List comprehension timing difference.

From	Bart Kastermans <bkasterm@gmail.com>
Newsgroups	comp.lang.python
Subject	Re: List comprehension timing difference.
Date	2011-09-02 20:15 -0600
Organization	MB-NET.NET for Open-News-Network e.V.
Message-ID	<87bov29xsg.fsf@gmail.com> (permalink)
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ting@thsu.org writes:

> On Sep 2, 9:54 am, Bart Kastermans <bkast...@gmail.com> wrote:
>> if d(a,b) == 1 and a < b:
>
> It will probably be faster if you reverse the evaluation order of that
> expression.
>
> if a<b and d(a,b)==1:
>
> That way the d() function is called less than half the time. Of course
> this assumes that a<b is a faster evaluation than d(a,b), but I think
> that's true for your example.
> --
> // T.Hsu

Indeed makes quite a difference, goes from 275 seconds down to
153 seconds.

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Thread

List comprehension timing difference. Bart Kastermans <bkasterm@gmail.com> - 2011-09-01 18:35 -0600
  Re: List comprehension timing difference. MRAB <python@mrabarnett.plus.com> - 2011-09-02 02:12 +0100
    Re: List comprehension timing difference. Bart Kastermans <bkasterm@gmail.com> - 2011-09-02 07:54 -0600
      Re: List comprehension timing difference. ting@thsu.org - 2011-09-02 07:50 -0700
        Re: List comprehension timing difference. Bart Kastermans <bkasterm@gmail.com> - 2011-09-02 20:15 -0600

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