From: "Mike Collins" <Mike AT NO_SPAM DOT e-col DOT freeserve DOT co DOT uk>
Newsgroups: comp.lang.c,comp.os.msdos.djgpp
Subject: Low-freq. Fourrier spectrum analisis
Date: Sat, 5 Feb 2000 18:52:20 -0000
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To: djgpp AT delorie DOT com
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Can anybody point me at a source of C-code for Fourrier analysis, please?

I want to find the amplitudes of the 8-12Hz, 12-16Hz, 16-20Hz, 20-24Hz bands
of a complex signal with a total bandwidth of not more than 30Hz.

Source code would be really great, but any pointers to a simple explanation
of how it works mathematically would also be most appreciated.

--
Mike Collins

PS. If replying by e-mail, please make the obvious correction to my address.