From: "Andrew Hurrell" <andrew AT acoustics DOT co DOT uk>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Imaginary Numbers
Date: 22 Nov 1999 14:19:37 GMT
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David Pinkerton <pinkerton AT desupernet DOT net> wrote in article
<383777ff AT news DOT desupernet DOT net>...

> Im working on making a small program that would display Fractals and the
> like , but all the equations ive seen involved imaginary numbers. Is
there a
> biult in constant somwhere in djgpp for dealing with these. i tried
setting
> a variable equal to sqrt(-1) but it came back undefined. thanks alot

GCC supports the C extension __complex__.

Look at the info gcc files
select the "C Extensions" menu and within that the "Complex" menu.

This should get you started.

If you then want to use functions of complex numbers I would suggest
that you download Steve Moshier's Cephes package from

www.netlib.org

The complex number part of this package uses this C extension in a
very user friendly manner and has some really cool maths capabilities.

Eli Z gave me a neat trick that aids debuggin code written with complex
arithmetic.  Specifically, compile with the -gstabs+ switch rather than the
basic -g3.  It works really well - thanks Eli !

If you get stuck -email me !