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mirror of https://github.com/cookiengineer/audacity synced 2025-05-05 14:18:53 +02:00
2010-01-24 09:19:39 +00:00

99 lines
2.1 KiB
C

/* A program to time complex forward and inverse fast fourier transform routines */
void four1(float data[], unsigned long nn, int isign);
#include <stdio.h>
#include <stdlib.h>
#include <fp.h>
#include <math.h>
#include "fftlib.h"
#include "fftext.h"
#if macintosh
#include <timer.h>
#endif
#define NSIZES 3 /* the number of different ffts sizes to time */
typedef struct{
float Re;
float Im;
} Complex;
void main(){
long fftSize[NSIZES] = {1024, 16384, 262144}; /* size of FFTs, must be powers of 2 */
long fftRepeats[NSIZES] = {2000, 50, 1}; /* number of timing loops */
Complex *a;
long isize;
long i1;
long TheErr;
long N;
long M;
#if macintosh
UnsignedWide TheTime1;
UnsignedWide TheTime2;
double TheTime;
#endif
printf(" %6d Byte Floats \n", sizeof(a[0].Re));
for (isize = 0; isize < NSIZES; isize++){
N = fftSize[isize];
printf("ffts size = %7d, ", N);
M = roundtol(LOG2(N));
TheErr = fftInit(M);
if(!TheErr){
a = (Complex *) malloc(N*sizeof(Complex) );
if (a == 0) TheErr = 2;
}
if(!TheErr){
/* set up a simple test case */
for (i1=0; i1<N; i1++){
a[i1].Re = sqrt(i1+.77777);
a[i1].Im = sqrt(i1+.22222);
}
#if macintosh
/* make sure routines are in physical (not virtual) memory */
Microseconds(&TheTime1);
ffts((float *)a, M, 1);
iffts((float *)a, M, 1);
Microseconds(&TheTime1);
for (i1=0;i1<fftRepeats[isize];i1++){ /* do many times for timing */
ffts((float *)a, M, 1);
iffts((float *)a, M, 1);
}
Microseconds(&TheTime2);
TheTime = (double)(TheTime2.hi - TheTime1.hi) * 65536.0 * 65536.0;
TheTime = (TheTime + (double)(TheTime2.lo - TheTime1.lo));
printf("ffts time = %12.1f µs, a[0].Re=%6e\n", TheTime/fftRepeats[isize]/2, a[0].Re);
#else
printf("start timing %12d real ffts's\n", fftRepeats[isize]*2);
for (i1=0;i1<fftRepeats[isize];i1++){ /* do many times for timing */
ffts((float *)a, M, 1);
iffts((float *)a, M, 1);
}
printf("end timing \n");
#endif
free(a);
fftFree();
}
else{
if(TheErr==2) printf(" out of memory \n");
else printf(" error \n");
fftFree();
}
}
printf(" Done. \n");
return;
}