fft-C

Fast Fouier Transform in C

This is introduction for the repository and I would like to describe what I have done for implementing fast fourier transform in C language. This is the course work in National Cheng Kung University. The professor tought me all these magic is ycshu. mathematicians are like magicians.

I wrote two versions to implement fast fourier transform algorithm one is using recursive function call the other is using loop to iterate.

Usage

It's welcome to use the algorithm but please note the LICENSE.

#include <complex.h>
#include "fft.h"


int main(){
    ...
    complex double in[200];
    complex double out[200];
    
    // call FFT recursive version which is faster
    FFT(in, out, 200);
    
    // or call FFT iteration version
    FFT_iter(in, out, 200);
    ...
    
    return 0
}

Contribution Guide

It's welcome to contribute the code. Please feel free to have modification. After you done, you can use verify.c to check the answer is correct or not. In the pull request I'll review the GitHub action.

Run the Code

Compile

If you have make

make

If you don't have make

gcc -Ofast fft.c example.c -o example
gcc -Ofast fft.c verify.c -o verify

Recursive

TO BE DONE

Iterative