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From: radford@calgary.UUCP
Newsgroups: comp.arch
Subject: Re: Calculating logs and exponentials
Message-ID: <950@vaxb.calgary.UUCP>
Date: Fri, 5-Jun-87 01:52:06 EDT
Article-I.D.: vaxb.950
Posted: Fri Jun  5 01:52:06 1987
Date-Received: Sat, 6-Jun-87 07:18:40 EDT
Organization: U. of Calgary, Calgary, Ab.
Lines: 15
Keywords: CORDIC

It turns out that my algorithm for computing logs and exponentials is
a special case of the CORDIC algorithm, for which see, e.g.:

    Walther, J. (1971) A Unified Algorithm for Elementary Functions,
    Joint Computer Conference Proceedings, vol. 38 (Spring 1971),
    pp. 379-385.

CORDIC also calculates sin, cos, and lots more, all in about the
time required for a multiply, assuming it is implemented in the same
technology as the multiply.

Thanks to all who responded. My next question is: Why is CORDIC not used
more?

   Radford Neal