Subj : Re: FFT  Fourier code
To   : comp.programming.threads
From : eg
Date : Fri Jan 14 2005 10:57 pm


Google is your friend.

http://www.fftw.org/links.html



james wrote:
> Hallo
> 
> I'm trying to implemet the code about FFT or DFT but i can't
> understand how is possible to calculate the real and the imaginary
> parameter from a list of number that describe a waveform.
> For example if i have a list of number like this and suppose a time
> between data of one second:
> 
> 0
> 10
> 20
> 30
> 20
> 10
> 0
> -10
> -20
> ...
> 
> now i need the real and the imaginary component from them to use FFT
> of DFT function that is like this:
> 
> int DFT(int dir,int m,double *x1,double *y1)
> {
> ...
> }
> 
> where 
> double *x1 = real component
> double *y1 = imaginary component
> 
> I've tryed to calculate these components but i get erroneous results.
> 
> Exist a code or similar that do it?
> 
> If you haven't this code can you tell me if you know some place in the
> web where is possible to find this kind of code?
> 
> At this moment i've found only complicated mathematical formulas. Not
> for me.
> 
> Thanks

.