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From: lindsay@gandalf.cs.cmu.edu (Donald Lindsay)
Newsgroups: comp.arch
Subject: Re: IEEE floating point
Message-ID: <13203@pt.cs.cmu.edu>
Date: 25 May 91 21:12:40 GMT
References: <9105240158.AA02761@ucbvax.Berkeley.EDU> <1991May24.173747.1483@zoo.toronto.edu>
Organization: Carnegie Mellon
Lines: 18

In article <9105240158.AA02761@ucbvax.Berkeley.EDU> 
	jbs@WATSON.IBM.COM writes:
>As to wrong answers, wrong answers are generally caused by
>users not knowing what they are doing.

I disagree. Dr. Kahan tells excellent anecdotes on this point, with
examples of well-respected products (e.g. Mathematica, hand
calculators) giving wrong answers to simple problems.

In article <1991May24.173747.1483@zoo.toronto.edu> 
	henry@zoo.toronto.edu (Henry Spencer) writes:
>However, well-designed tools like IEEE FP improve the odds a lot.

Seconded. People who think that the common alternatives are as well
designed, are probably unfamiliar with the sore points.  For example,
Cray format allows a value which will overflow if multiplied by 1 ...
-- 
Don		D.C.Lindsay 	Carnegie Mellon Robotics Institute