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From: dana@hardy.hdw.csd.harris.com (Dan Aksel)
Newsgroups: comp.arch
Subject: Re: IBM floating point using logarithms
Message-ID: <3637@travis.csd.harris.com>
Date: 11 Jun 91 12:27:00 GMT
References: <1991Jun10.171824.10980@solbourne.com>
Sender: news@travis.csd.harris.com
Organization: Harris Computer Systems, Ft. Lauderdale, FL
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In article <1991Jun10.171824.10980@solbourne.com> McGuire@solbourne.com (Jim McGuire) writes:
>	"The key to the hybrid computational unit
>	is a new approach to representing logarithms
>	that closely parallels the IEEE P754 32-bit
>	floating-point format."
>
>	"The result is a conversion method simple enough
>	to cast in hardware..."

I've never heard of this.  The technique is to take the log of a IEEE P754
number as it comes in from memory?  Then mulitplies become adds, divisions
become subtraction, exponentiate becomes multiplication...

AND ADDITION AND SUBTRACTION BECOME A MESS !

I assume there is some quick translation to get a log of a number?  I'd really
like to hear more about this one.  Anyone out there with more details, I'd
appreciate a followup post.  Thank you.
---
Dan Aksel