From: Horst Kraemer <horst DOT kraemer AT gmx DOT de>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: modf BROKEN ??
Date: Tue, 01 Aug 2000 19:37:54 +0200
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To: djgpp AT delorie DOT com
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On Mon, 31 Jul 2000 22:37:40 -0400, Radical NetSurfer
<radsmail AT juno DOT com> wrote:

> Why does the following program INCORRECTLY display
> the fractional part?

It does display CORRECTLY the fractional part.

The problem is that you think that adding up 20 times the floating
point value 0.1 will yield exactly 2.0. The number 0.1 isn't exactly
representable as a binary floating point number. Adding up the "wrong"
binary value associated to '0.1' will increase the representation
error.

Using FP numbers as contrl variable in a loop is almost always an
error.

Regards
Horst