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From: "Adam Beneschan" <adam@irvine.com>
Subject: Re: Unsigned Integer Restraint Errors
Date: 13 Mar 2007 10:31:57 -0700
Date: 2007-03-13T10:31:57-07:00	[thread overview]
Message-ID: <1173807117.252152.63410@h3g2000cwc.googlegroups.com> (raw)
In-Reply-To: <10l92gksnkfjl$.1rhbr6sokrtjy.dlg@40tude.net>

On Mar 13, 10:23 am, "Dmitry A. Kazakov" <mail...@dmitry-kazakov.de>
wrote:

>
> BTW, the arithmetic complexity can be further "reduced" by removing
> multiplication and computing k**2 using binomial decomposition
> (k+1)*(k+1)=k*k+2*k+1. So it could be:
>
> quadratic := 1; -- k*k, k=1
> linear := 2; -- 2*k+1, k=1
>
> loop
>    linear := linear + 2; -- 2*k+1
>    quadratic := quadratic + linear; -- k*k
>    exit when k>=n;
>    ...
> end loop;

Yep, that's certainly the way I'd do it on some of the *really* bare-
bones computers I occasionally had to work with---like the 6502 (used
in the Apple II).  Some of those chips, including the 6502, didn't
come with integer multiplication or division.

                                 -- Adam




  reply	other threads:[~2007-03-13 17:31 UTC|newest]

Thread overview: 30+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-03-12 15:07 Unsigned Integer Restraint Errors frikk
2007-03-12 16:27 ` Georg Bauhaus
2007-03-12 17:17 ` Adam Beneschan
2007-03-12 17:23 ` Adam Beneschan
2007-03-12 18:11   ` frikk
2007-03-12 20:00     ` frikk
2007-03-12 20:07       ` Adam Beneschan
2007-03-12 18:00 ` Dmitry A. Kazakov
2007-03-12 19:00   ` Martin Krischik
2007-03-12 21:13     ` Dmitry A. Kazakov
2007-03-12 19:13   ` frikk
2007-03-12 19:22     ` Randy Brukardt
2007-03-13  3:13       ` Jeffrey R. Carter
2007-03-13  3:00         ` Randy Brukardt
2007-03-13 12:09           ` frikk
2007-03-13 14:58             ` frikk
2007-03-13 15:31               ` frikk
2007-03-13 15:59                 ` Robert A Duff
2007-03-13 16:18                 ` Dmitry A. Kazakov
2007-03-13 16:21                 ` Jeffrey R. Carter
2007-03-13 16:04               ` Adam Beneschan
2007-03-13 16:41                 ` Adam Beneschan
2007-03-13 16:42                   ` Adam Beneschan
2007-03-14 14:06                     ` frikk
2007-03-13 17:23                 ` Dmitry A. Kazakov
2007-03-13 17:31                   ` Adam Beneschan [this message]
2007-03-14  0:54                   ` Jeffrey R. Carter
2007-03-16 13:38                   ` frikk
2007-03-13 16:16           ` Jeffrey R. Carter
2007-03-12 21:04     ` Dmitry A. Kazakov
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