aparler/RosettaCodeData
1
0
Fork 0
Code Issues 12 Pull requests 3 Projects Releases Packages Wiki Activity Actions

2016 Update

Browse source
This commit is contained in:
Tina Müller 2016-12-05 22:15:40 +01:00
parent 948b86eafa
commit dcf5d15da3
7965 changed files with 139854 additions and 31002 deletions
Download patch file Download diff file Expand all files Collapse all files

23
Task/Fast-Fourier-transform/C/fast-fourier-transform-1.c
View file

@ -27,23 +27,24 @@ void fft(cplx buf[], int n)
_fft(buf, out, n, 1);
}
void show(const char * s, cplx buf[]) {
printf("%s", s);
for (int i = 0; i < 8; i++)
if (!cimag(buf[i]))
printf("%g ", creal(buf[i]));
else
printf("(%g, %g) ", creal(buf[i]), cimag(buf[i]));
}
int main()
{
PI = atan2(1, 1) * 4;
cplx buf[] = {1, 1, 1, 1, 0, 0, 0, 0};
void show(const char * s) {
printf("%s", s);
for (int i = 0; i < 8; i++)
if (!cimag(buf[i]))
printf("%g ", creal(buf[i]));
else
printf("(%g, %g) ", creal(buf[i]), cimag(buf[i]));
}
show("Data: ");
show("Data: ", buf);
fft(buf, 8);
show("\nFFT : ");
show("\nFFT : ", buf);
return 0;
}

43
Task/Fast-Fourier-transform/C/fast-fourier-transform-2.c
View file

@ -1,2 +1,41 @@
Data: 1 1 1 1 0 0 0 0
FFT : 4 (1, -2.41421) 0 (1, -0.414214) 0 (1, 0.414214) 0 (1, 2.41421)
#include <stdio.h>
#include <Accelerate/Accelerate.h>
void fft(DSPComplex buf[], int n) {
float inputMemory[2*n];
float outputMemory[2*n];
// half for real and half for complex
DSPSplitComplex inputSplit = {inputMemory, inputMemory + n};
DSPSplitComplex outputSplit = {outputMemory, outputMemory + n};
vDSP_ctoz(buf, 2, &inputSplit, 1, n);
vDSP_DFT_Setup setup = vDSP_DFT_zop_CreateSetup(NULL, n, vDSP_DFT_FORWARD);
vDSP_DFT_Execute(setup,
inputSplit.realp, inputSplit.imagp,
outputSplit.realp, outputSplit.imagp);
vDSP_ztoc(&outputSplit, 1, buf, 2, n);
}
void show(const char *s, DSPComplex buf[], int n) {
printf("%s", s);
for (int i = 0; i < n; i++)
if (!buf[i].imag)
printf("%g ", buf[i].real);
else
printf("(%g, %g) ", buf[i].real, buf[i].imag);
printf("\n");
}
int main() {
DSPComplex buf[] = {{1,0}, {1,0}, {1,0}, {1,0}, {0,0}, {0,0}, {0,0}, {0,0}};
show("Data: ", buf, 8);
fft(buf, 8);
show("FFT : ", buf, 8);
return 0;
}

50
Task/Fast-Fourier-transform/C/fast-fourier-transform.c
View file

@ -1,50 +0,0 @@
#include <stdio.h>
#include <math.h>
#include <complex.h>
double PI;
typedef double complex cplx;
void _fft(cplx buf[], cplx out[], int n, int step)
{
if (step < n) {
_fft(out, buf, n, step * 2);
_fft(out + step, buf + step, n, step * 2);
for (int i = 0; i < n; i += 2 * step) {
cplx t = cexp(-I * PI * i / n) * out[i + step];
buf[i / 2] = out[i] + t;
buf[(i + n)/2] = out[i] - t;
}
}
}
void fft(cplx buf[], int n)
{
cplx out[n];
for (int i = 0; i < n; i++) out[i] = buf[i];
_fft(buf, out, n, 1);
}
void show(const char * s, cplx buf[]) {
printf("%s", s);
for (int i = 0; i < 8; i++)
if (!cimag(buf[i]))
printf("%g ", creal(buf[i]));
else
printf("(%g, %g) ", creal(buf[i]), cimag(buf[i]));
}
int main()
{
PI = atan2(1, 1) * 4;
cplx buf[] = {1, 1, 1, 1, 0, 0, 0, 0};
show("Data: ", buf);
fft(buf, 8);
show("\nFFT : ", buf);
return 0;
}