快速傅里叶变换算法 c语言编程

#include<D:\Microchip\MPLAB C30\support\dsPIC30F\h\p30f6014.h>
#include <stdlib.h>
#include <math.h>
#define ZERO 0.00001
#define PI 3.1415926
#define ISZERO(i) (fabs(i)<0.00001) 
typedef struct
{
float real;
float img;
}COMPLEX;
unsigned BinInv(unsigned target,unsigned width);
COMPLEX  *ComAdd(const COMPLEX  *add1, const COMPLEX  *add2,COMPLEX  *result);
COMPLEX  *ComSub(const COMPLEX  *sub1, const COMPLEX  *sub2,COMPLEX  *result);
COMPLEX  *ComMul(const COMPLEX  *mul1, const COMPLEX  *mul2,COMPLEX  *result);
COMPLEX *FFT(COMPLEX  *X,COMPLEX  *x, unsigned   N);
int main()
{
double k;
//double Q;
unsigned NUM = 64;
COMPLEX *P=NULL,*X,*x;
unsigned i = 0;
float tmp;
int sam_freq = 128;
for(i=0;i<NUM;i++)
{
tmp = 1.00/sam_freq*i;
x[i].real =1.5*sin(2*PI*50*tmp)+0.9*sin(2*PI*100*tmp)+0.5*sin(2*PI*150*tmp);
x[i].img = 0.0;