From: "Alexei A. Frounze" <dummy_addressee AT hotmail DOT com>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: exp() doesn't work !
Date: Tue, 22 May 2001 14:37:53 -0400
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To: djgpp AT delorie DOT com
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Reply-To: djgpp AT delorie DOT com

#include <stdio.h>
#include <stdlib.h>
#include <math.h>

int main() //int argc, char **argv)
{
 double s;
 s = exp (1e-15);
 printf("%40.20g\n",s);
 exit(EXIT_SUCCESS);
}

gives approx 1 + 1e-15 as expected from the expansion: e^x = 1 + x + x^/2 +
x^3/6 + ...
everything is correct, just make sure that those small numbers can still be
represented by double type and their contribution in your formulas counts,
is not lost because of their small value.

Good Luck
--
Alexei A. Frounze
alexfru [AT] chat [DOT] ru
http://alexfru.chat.ru
http://members.xoom.com/alexfru/
http://welcome.to/pmode/