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From: leban@par3.cs.umass.edu (Bruce Leban)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Why can't the Mac add?
Message-ID: <20360@dime.cs.umass.edu>
Date: 24 Sep 90 23:41:14 GMT
References: <45060@apple.Apple.COM>
Sender: news@dime.cs.umass.edu
Reply-To: leban@par3.cs.umass.edu (Bruce Leban)
Organization: University of Massachusetts, Amherst
Lines: 14

Several people have suggested replacing:
	for (x=0.0;x!=10.0;x+=0.2)
with variations of:
	for (x = 0.0; x < 10.0+epsilon; x += 0.2)
but that is not the best suggestion since the floating point error
compounds on each addition.  Presumably, what you want is the nearest
approximation to the sequence 0.0, 0.2, 0.4, etc.  In that case, do:
	int y; float x;
	for (y = 0; x = y/10, y <= 100; y += 2)
An excellent reference is the /Elements of Programming Style/ which points
out that "0.1 * 10.0 is hardly ever 1.0".

	--- Bruce
	Leban@cs.umass.edu  @amherst.mass.usa.earth