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From: ken@rochester.UUCP (Ipse dixit)
Newsgroups: net.arch
Subject: Re: Representations of Real Numbers
Message-ID: <15361@rochester.UUCP>
Date: Sun, 16-Feb-86 11:24:00 EST
Article-I.D.: rocheste.15361
Posted: Sun Feb 16 11:24:00 1986
Date-Received: Mon, 17-Feb-86 06:24:21 EST
References: <931@houxa.UUCP> <17200002@umn-cs.UUCP>
Reply-To: ken@rochester.UUCP (Ipse dixit)
Organization: Sans Serif
Lines: 21

In article <17200002@umn-cs.UUCP> herndon@umn-cs.UUCP writes:
>  There was an article in byte a while back suggesting an alternate
>representation for floating point numbers which might be useful
>on a micro... unfortunately I've forgotten all the details.  I
>think the idea was to keep the logarithm of the number, and then
>do multiplies and divisions by adding and subtracting... mildly
>interesting, anyway.

In 1979, Aug I think, an article appeared in CACM with the above
scheme.  It was called FOCUS. The rationale was that data from real
world sensors, e.g. light, sound follow logarithmic scales so there
were advantages to being able to multiply or divide quickly on cheap
micros, and the lack of a true zero didn't matter much, the smallest
number being essentially below thermal noise levels.

I am curious to know if anybody actually used this scheme.

	Ken
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