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Date: Sun, 25 Aug 2013 08:05:50 +1000
Subject: Re: Fast conversion of numbers to numerator/denominator pairs
From: Tim Delaney <timothy.c.delaney@gmail.com>
To: "Steven D'Aprano" <steve+comp.lang.python@pearwood.info>
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On 25 August 2013 07:59, Tim Delaney <timothy.c.delaney@gmail.com> wrote:

> Breakdown of the above (for 19 digits):
>
> d.as_tuple() takes about 35% of the time.
>
> The multiply and add takes about 55% of the time.
>
> The exponentiation takes about 10% of the time.
>

Bah - sent before complete.

Since the multiply and add takes such a significant proportion of the time,
compiling the above with Cython should gain you a big win as well. Or find
some other way to turn that loop into native code.

Tim Delaney

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<div dir=3D"ltr">On 25 August 2013 07:59, Tim Delaney <span dir=3D"ltr">&lt=
;<a href=3D"mailto:timothy.c.delaney@gmail.com" target=3D"_blank">timothy.c=
.delaney@gmail.com</a>&gt;</span> wrote:<br><div class=3D"gmail_extra"><div=
 class=3D"gmail_quote">
<blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1p=
x #ccc solid;padding-left:1ex"><div dir=3D"ltr"><div class=3D"im"><span sty=
le=3D"color:rgb(34,34,34)">Breakdown of the above (for 19 digits):</span><b=
r></div>
<div class=3D"gmail_extra"><div class=3D"gmail_quote"><div>
<br></div><div>d.as_tuple() takes about 35% of the time.</div><div><br></di=
v><div>The multiply and add takes about 55% of the time.</div><div><br></di=
v><div>The exponentiation takes about 10% of the time.</div></div></div>
</div></blockquote><div><br></div><div>Bah - sent before complete.=C2=A0</d=
iv><div><br></div><div>Since the multiply and add takes such a significant =
proportion of the time, compiling the above with Cython should gain you a b=
ig win as well. Or find some other way to turn that loop into native code.<=
/div>
<div><br></div><div>Tim Delaney</div></div></div></div>

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