Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!mnetor!seismo!ll-xn!ames!amdahl!pyramid!batcomputer!braner
From: braner@batcomputer.tn.cornell.edu (braner)
Newsgroups: comp.lang.c
Subject: Re: Comments on ANSI public Oct 86 Public review draft.
Message-ID: <377@batcomputer.tn.cornell.edu>
Date: Tue, 10-Mar-87 00:25:28 EST
Article-I.D.: batcompu.377
Posted: Tue Mar 10 00:25:28 1987
Date-Received: Tue, 10-Mar-87 23:01:58 EST
References: <4804@brl-adm.ARPA>
Reply-To: braner@batcomputer.UUCP (braner)
Organization: Theory Center, Cornell University, Ithaca NY
Lines: 17
Summary: double x,y; if (x==y)... should be retained!

[]

In many numerical programs you do not want to repeat some calculation
if some floating-point variable has not changed.  Therefore,

	double x,y;
	x = y;
	...
	if (x==y) ...

SHOULD be available (and work correctly) even in implementations where
(x*y == y*x) fails.  And it should be no problem to implement, since
x and y are two copies of the same number in the same internal format.
(This is very different from the common mistake of expecting infinite
precision when using FP variables in loop termination criteria...)

- Moshe Braner