From: Erik Max Francis <max AT alcyone DOT com>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Variable malfunction?
Date: Sat, 19 Dec 1998 12:23:55 -0800
Organization: Alcyone Systems
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Veli-Pekka Kilpeläinen wrote:

> gr = index / 8192 * pi2;        // gr is always zero!

It's because you're letting it use the default order of operations, in
which the division occurs in integer math, and so the result is always
zero, which is them multiplied by a double, promoted to double, but is
still zero.

What you need to do is promote the computation to double early on.  The
easiest way to do this is to make the 8192 constant floating point:

    gr = index/8192.*pi2;

Now to calculate index/8192., index must be promoted to double, and you
get the result that you want.

-- 
Erik Max Francis / email max AT alcyone DOT com / whois mf303 / icq 16063900
Alcyone Systems / irc maxxon (efnet) / finger max AT finger DOT alcyone DOT com
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