sobota, 15 kwietnia 2017
Shared memory by 2 variables instead of pointers, 2 variables in 1 memory
//Shared memory by 2 variables instead of pointers, 2 variables in 1 memory
//współdzielenie pamięci przez 2 zmienne zamiast wskaźników, 2 zmienne w 1 pamięci
//source:
//http://stackoverflow.com/questions/4629317/what-does-int-mean
// http://www.cplusplus.com/forum/windows/17153/
//author marcin matysek (r)ewertyn.PL
#include <iostream>
#include <conio.h>
#include <stdlib.h>
using namespace std;
void funkcja(int & nb3);
int main()
{
int nb1=0;
int &nb2=nb1;
cout<<"Variable1 value= "<<nb1<<" Its address is: "<<&nb1<<endl;
cout<<"Variable2 value= "<<nb2<<" Its address is: "<<&nb2<<endl;
nb2=10;
cout<<endl;
cout<<"After modifying the 2 variables have value:"<<endl;
cout<<"Variable1 value= "<<nb1<<" Its address is: "<<&nb1<<endl;
cout<<"Variable2 value= "<<nb2<<" Its address is: "<<&nb2<<endl;
funkcja(nb1);
cout<<endl;
cout<<"After leaving the function:"<<endl;
cout<<"Variable1 value= "<<nb1<<" Its address is: "<<&nb1<<endl;
cout<<"Variable2 value= "<<nb2<<" Its address is: "<<&nb2<<endl;
system("pause");
return 0;
}
void funkcja(int & nb3)
{
cout<<endl;
cout<<"in function Variable 3 have value and address of Variable1:"<<endl;
cout<<"Variable3 value= "<<nb3<<" Its address is: "<<&nb3<<endl;
cout<<"after modification Variable 3 ,Variable 3 In function has value:"<<endl;
nb3=20;
cout<<endl;
cout<<"Variable3 value= "<<nb3<<" Its address is: "<<&nb3<<endl;
}
inverse fourier transform iFFT radix-4 for N=4096 algorithm c++ source code implementation
//source:
//https://www.google.ch/patents/US6957241
//http://www.google.ch/patents/US20020083107
//https://www.beechwood.eu/fft-implementation-r2-dit-r4-dif-r8-dif/
//http://www.cmlab.csie.ntu.edu.tw/cml/dsp/training/coding/transform/fft.html
//http://dsp.stackexchange.com/questions/3481/radix-4-fft-implementation
//author marcin matysek (r)ewertyn.PL
//szybka odwrotna transformacja fouriera iFFT radix-4 dla N=4096 algorytm c++ kod zródlowy implementacja
//inverse fourier transform iFFT radix-4 for N=4096 algorithm c++ source code implementation
#include <iostream>
#include "conio.h"
#include <stdlib.h>
#include <math.h>
#include <cmath>
#include <time.h>
#include <complex>
#include <fstream>
using namespace std;
//complex number method:
void fun_inverse_bits_radix_4(int N,std::complex<double> tab[]);
void fun_fourier_transform_FFT_radix_4_N_4096(int N,std::complex<double> tab[]);
void fun_inverse_fourier_transform_FFT_radix_4_N_4096(int N,std::complex<double> tab[]);
void fun_fourier_transform_DFT_method5_full_complex(int N,std::complex<double> tab[]);
int fi=0;
static double diffclock(clock_t clock2,clock_t clock1)
{
double diffticks=clock1-clock2;
double diffms=(diffticks)/(CLOCKS_PER_SEC/1000);
return diffms;
}
int main()
{
int N;
//if N==period of signal in table tab[] then resolution = 1 Hz
N=4096;
std::complex<double> tab2[4096]={};
std::complex<double> tab3[4096]={};
for(int i=0;i<N;i++)
{
tab2[i].real()=i+1;
tab2[i].imag()=N+i+1;
tab3[i].real()=i+1;
tab3[i].imag()=N+i+1;
}
double time2;
double zmienna=0;
cout<<"signal 1="<<endl;
system("pause");
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab2[j].real()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab2[j].imag()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
cout<<"signal 2="<<endl;
system("pause");
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab3[j].real()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab3[j].imag()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
system("pause");
clock_t start = clock();
fun_fourier_transform_DFT_method5_full_complex(N,tab3);
//////////////////////////////////////////////////////////
fun_fourier_transform_FFT_radix_4_N_4096(N,tab2);
fun_inverse_bits_radix_4(N,tab2);
///////////////////////////////////////////////////////////
time2=diffclock( start, clock() );
cout<<"frequency Hz radix-4 real()"<<endl;
system("pause");
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab2[j].real()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
cout<<"frequency Hz radix-4 imag()"<<endl;
system("pause");
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab2[j].imag()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
cout<<"frequency Hz DFT real()"<<endl;
system("pause");
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab3[j].real()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
cout<<"frequency Hz DFT imag()"<<endl;
system("pause");
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab3[j].imag()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
cout<<"if radix-4 == DFT tab2[j].real(): "<<endl;system("pause");
for(int j=0;j<N;j++)
{
if(((tab3[j].real()-tab2[j].real()>=-0.03)&&(tab3[j].real()-tab2[j].real()<=0.03)))
{
cout.precision(4);
cout<<round(tab2[j].real()*1000)/1000<<" ";//system("pause");
}
else {
cout<<-1<<" ........ ";
}
}
system("pause");
cout<<endl;
/////////////////////////////////////////////////////////////////
fun_inverse_fourier_transform_FFT_radix_4_N_4096(N,tab2);
fun_inverse_bits_radix_4(N,tab2);
////////////////////////////////////////////////////////////////
cout<<"inverse/signal= real()"<<endl;
system("pause");
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab2[j].real()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
cout<<"inverse/signal= imag()"<<endl;
system("pause");
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab2[j].imag()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
cout<<endl;
system("pause");
return 0;
}
//////////////////////////////////////////////
void fun_inverse_bits_radix_4(int N,std::complex<double> tab[])
{
}
///////////////////////////////////////////////////
void fun_fourier_transform_DFT_method5_full_complex(int N,std::complex<double> tab[])
{
const double pi=3.141592653589793238462;
std::complex<double> tab2[4096]={}; // tab2[]==N
std::complex<double> w[1]={{1,1}};
double zmienna1=2*pi/(float)N;
double fi2=fi;
for (int i=0;i<N;i++)
{
for(int j=0;j<N;j++)
{
//complex number method:
w[0].real()=cos(i*j*zmienna1+fi2);
w[0].imag()=(-sin(i*j*zmienna1+fi2));
tab2[i]=tab2[i]+tab[j]*w[0];
}
}
for(int j=0;j<N;j++)
{
tab[j].real() =tab2[j].real()*2/N;
tab[j].imag() =tab2[j].imag()*2/N;
}
}
//////////////////
void fun_fourier_transform_FFT_radix_4_N_4096(int N,std::complex<double> tab[])
{
const double pi=3.141592653589793238462;
std::complex<double> w1[1]={{1,0}};
std::complex<double> w2[1]={{1,0}};
std::complex<double> w3[1]={{1,0}};
std::complex<double> w4[1]={{1,0}};
std::complex<double> w5[1]={{1,0}};
std::complex<double> w6[1]={{1,0}};
std::complex<double> tmp1,tmp2,tmp3,tmp4;
std::complex<double> tmp10,tmp20,tmp30,tmp40;
int nr1=0,nr2=0,nr3=0,nr4=0,nr5=0;;
int nb_stages=0,rx4=0;
double tmp5;
int increment=0;
int nn=0;
w5[0].real()=0;
w5[0].imag()=-1;
w6[0].real()=0;
w6[0].imag()=1;
tmp5=2*pi/(N/1);
rx4=4;//radix-4
nn=N;
for(int i=0;i<100;i++)
{
nn=(float)nn/(float)rx4;
if(nn>=1.0)
{
nb_stages++;
}
}
//stage 1
for(int i=0;i<(N/rx4);i++)
{
w1[0].real()=cos(0*tmp5);
w1[0].imag()=-sin(0*tmp5);
w2[0].real()=cos(0*tmp5);
w2[0].imag()=-sin(0*tmp5);
w3[0].real()=cos(0*tmp5);
w3[0].imag()=-sin(0*tmp5);
w4[0].real()=cos(0*tmp5);
w4[0].imag()=-sin(0*tmp5);
tmp1=w1[0]*tab[i+0];
tmp2=w2[0]*tab[i+N/4];
tmp3=w3[0]*tab[i+N/2];
tmp4=w4[0]*tab[i+3*N/4];
//radix-4
tmp10=tmp1+tmp2+ tmp3+tmp4;
tmp20=tmp1-tmp3+w5[0]*(tmp2-tmp4);
tmp30=tmp1-tmp2+ tmp3-tmp4;
tmp40=tmp1-tmp3+w6[0]*(tmp2-tmp4);
tab[i] =tmp10;
tab[i+N/4] =tmp20;
tab[i+N/2] =tmp30;
tab[i+3*N/4] =tmp40;
}
/////////////////////////////////////////////////////////////////////////////////
increment=0;
for(int stg=1;stg<nb_stages;stg++)
{
nr1=pow(rx4,0+increment);
nr2=pow(rx4,1+increment);
nr3=pow(rx4,2+increment);
nr4=pow(rx4,(nb_stages-2-increment));
nr5=pow(rx4,0+increment);
for(int m=0;m<nr5;m++)//stage 2
{
for(int i=0;i<rx4;i++)
{
for(int j=0;j<nr4;j++)
{
w1[0].real()= cos((nr5*0*i*(j+nr4*0)+nr5*1*i*j)*tmp5);
w1[0].imag()=-sin((nr5*0*i*(j+nr4*0)+nr5*1*i*j)*tmp5);
w2[0].real()= cos((nr5*1*i*(j+nr4*1)+nr5*0*i*j)*tmp5);
w2[0].imag()=-sin((nr5*1*i*(j+nr4*1)+nr5*0*i*j)*tmp5);
w3[0].real()= cos((nr5*2*i*(j+nr4*1)-nr5*1*i*j)*tmp5);
w3[0].imag()=-sin((nr5*2*i*(j+nr4*1)-nr5*1*i*j)*tmp5);
w4[0].real()= cos((nr5*3*i*(j+nr4*1)-nr5*2*i*j)*tmp5);
w4[0].imag()=-sin((nr5*3*i*(j+nr4*1)-nr5*2*i*j)*tmp5);
tmp1=w1[0]*tab[0*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j];
tmp2=w2[0]*tab[1*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j];
tmp3=w3[0]*tab[2*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j];
tmp4=w4[0]*tab[3*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j];
//radix-4
tmp10=tmp1+tmp2+ tmp3+tmp4;
tmp20=tmp1-tmp3+w5[0]*(tmp2-tmp4);
tmp30=tmp1-tmp2+ tmp3-tmp4;
tmp40=tmp1-tmp3+w6[0]*(tmp2-tmp4);
tab[0*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j]=tmp10;
tab[1*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j]=tmp20;
tab[2*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j]=tmp30;
tab[3*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j]=tmp40;
}
}
}
increment++;
}
////////////////////////////////////////////////////////////////////////////////
for(int j=0;j<N;j++)
{
tab[j].real() =tab[j].real()*2/N;
tab[j].imag() =tab[j].imag()*2/N;
}
}
////////////////////////////////
void fun_inverse_fourier_transform_FFT_radix_4_N_4096(int N,std::complex<double> tab[])
{
const double pi=3.141592653589793238462;
std::complex<double> w1[1]={{1,0}};
std::complex<double> w2[1]={{1,0}};
std::complex<double> w3[1]={{1,0}};
std::complex<double> w4[1]={{1,0}};
std::complex<double> w5[1]={{1,0}};
std::complex<double> w6[1]={{1,0}};
std::complex<double> tmp1,tmp2,tmp3,tmp4;
std::complex<double> tmp10,tmp20,tmp30,tmp40;
int nr1=0,nr2=0,nr3=0,nr4=0,nr5=0;;
int nb_stages=0,rx4=0;
double tmp5;
int increment=0;
int nn=0;
w5[0].real()=0;
w5[0].imag()=1;
w6[0].real()=0;
w6[0].imag()=-1;
tmp5=2*pi/(N/1);
rx4=4;//radix-4
nn=N;
for(int i=0;i<100;i++)
{
nn=(float)nn/(float)rx4;
if(nn>=1.0)
{
nb_stages++;
}
}
//stage 1
for(int i=0;i<(N/rx4);i++)
{
w1[0].real()=cos(0*tmp5);
w1[0].imag()= sin(0*tmp5);
w2[0].real()=cos(0*tmp5);
w2[0].imag()= sin(0*tmp5);
w3[0].real()=cos(0*tmp5);
w3[0].imag()= sin(0*tmp5);
w4[0].real()=cos(0*tmp5);
w4[0].imag()= sin(0*tmp5);
tmp1=w1[0]*tab[i+0];
tmp2=w2[0]*tab[i+N/4];
tmp3=w3[0]*tab[i+N/2];
tmp4=w4[0]*tab[i+3*N/4];
//radix-4
tmp10=tmp1+tmp2+ tmp3+tmp4;
tmp20=tmp1-tmp3+w5[0]*(tmp2-tmp4);
tmp30=tmp1-tmp2+ tmp3-tmp4;
tmp40=tmp1-tmp3+w6[0]*(tmp2-tmp4);
tab[i] =tmp10;
tab[i+N/4] =tmp20;
tab[i+N/2] =tmp30;
tab[i+3*N/4] =tmp40;
}
/////////////////////////////////////////////////////////////////////////////////
increment=0;
for(int stg=1;stg<nb_stages;stg++)
{
nr1=pow(rx4,0+increment);
nr2=pow(rx4,1+increment);
nr3=pow(rx4,2+increment);
nr4=pow(rx4,(nb_stages-2-increment));
nr5=pow(rx4,0+increment);
for(int m=0;m<nr5;m++)//stage 2
{
for(int i=0;i<rx4;i++)
{
for(int j=0;j<nr4;j++)
{
w1[0].real()= cos((nr5*0*i*(j+nr4*0)+nr5*1*i*j)*tmp5);
w1[0].imag()= sin((nr5*0*i*(j+nr4*0)+nr5*1*i*j)*tmp5);
w2[0].real()= cos((nr5*1*i*(j+nr4*1)+nr5*0*i*j)*tmp5);
w2[0].imag()= sin((nr5*1*i*(j+nr4*1)+nr5*0*i*j)*tmp5);
w3[0].real()= cos((nr5*2*i*(j+nr4*1)-nr5*1*i*j)*tmp5);
w3[0].imag()= sin((nr5*2*i*(j+nr4*1)-nr5*1*i*j)*tmp5);
w4[0].real()= cos((nr5*3*i*(j+nr4*1)-nr5*2*i*j)*tmp5);
w4[0].imag()= sin((nr5*3*i*(j+nr4*1)-nr5*2*i*j)*tmp5);
tmp1=w1[0]*tab[0*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j];
tmp2=w2[0]*tab[1*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j];
tmp3=w3[0]*tab[2*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j];
tmp4=w4[0]*tab[3*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j];
//radix-4
tmp10=tmp1+tmp2+ tmp3+tmp4;
tmp20=tmp1-tmp3+w5[0]*(tmp2-tmp4);
tmp30=tmp1-tmp2+ tmp3-tmp4;
tmp40=tmp1-tmp3+w6[0]*(tmp2-tmp4);
tab[0*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j]=tmp10;
tab[1*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j]=tmp20;
tab[2*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j]=tmp30;
tab[3*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j]=tmp40;
}
}
}
increment++;
}
/////////////////////////////////////////////////////////////
for(int j=0;j<N;j++)
{
tab[j].real() =tab[j].real()*0.5;
tab[j].imag() =tab[j].imag()*0.5;
}
}
//////////////////
//this is new in that method:
//when you want to have equal results that are in false modificator in normal FFT then change this:
/*
fun_fourier_transform_FFT_radix_4_N_256_official
{
for(int j=0;j<N;j++)
{
tab[j].real() =tab[j].real()*2/N;
tab[j].imag() =tab[j].imag()*2/N;
}
}
//and:
fun_inverse_fourier_transform_FFT_radix_4_N_256_official
{
for(int j=0;j<N;j++)
{
tab[j].real() =tab[j].real()*0.5;
tab[j].imag() =tab[j].imag()*0.5;
}
}
//for official modificator that is only in inverse FFT:
fun_fourier_transform_FFT_radix_4_N_256_official
{
}
fun_inverse_fourier_transform_FFT_radix_4_N_256_official
{
for(int i=0;i<N;i++)
{
tablica1[0][i]=tablica1[0][i]*1/(float)N;
tablica1[1][i]=tablica1[1][i]*1/(float)N;
}
}
*/
//haven't try it with other function that cos(x)+jsin(x)=sin(x+pi/2)+jsin(x)
//https://www.google.ch/patents/US6957241
//http://www.google.ch/patents/US20020083107
//https://www.beechwood.eu/fft-implementation-r2-dit-r4-dif-r8-dif/
//http://www.cmlab.csie.ntu.edu.tw/cml/dsp/training/coding/transform/fft.html
//http://dsp.stackexchange.com/questions/3481/radix-4-fft-implementation
//author marcin matysek (r)ewertyn.PL
//szybka odwrotna transformacja fouriera iFFT radix-4 dla N=4096 algorytm c++ kod zródlowy implementacja
//inverse fourier transform iFFT radix-4 for N=4096 algorithm c++ source code implementation
#include <iostream>
#include "conio.h"
#include <stdlib.h>
#include <math.h>
#include <cmath>
#include <time.h>
#include <complex>
#include <fstream>
using namespace std;
//complex number method:
void fun_inverse_bits_radix_4(int N,std::complex<double> tab[]);
void fun_fourier_transform_FFT_radix_4_N_4096(int N,std::complex<double> tab[]);
void fun_inverse_fourier_transform_FFT_radix_4_N_4096(int N,std::complex<double> tab[]);
void fun_fourier_transform_DFT_method5_full_complex(int N,std::complex<double> tab[]);
int fi=0;
static double diffclock(clock_t clock2,clock_t clock1)
{
double diffticks=clock1-clock2;
double diffms=(diffticks)/(CLOCKS_PER_SEC/1000);
return diffms;
}
int main()
{
int N;
//if N==period of signal in table tab[] then resolution = 1 Hz
N=4096;
std::complex<double> tab2[4096]={};
std::complex<double> tab3[4096]={};
for(int i=0;i<N;i++)
{
tab2[i].real()=i+1;
tab2[i].imag()=N+i+1;
tab3[i].real()=i+1;
tab3[i].imag()=N+i+1;
}
double time2;
double zmienna=0;
cout<<"signal 1="<<endl;
system("pause");
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab2[j].real()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab2[j].imag()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
cout<<"signal 2="<<endl;
system("pause");
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab3[j].real()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab3[j].imag()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
system("pause");
clock_t start = clock();
fun_fourier_transform_DFT_method5_full_complex(N,tab3);
//////////////////////////////////////////////////////////
fun_fourier_transform_FFT_radix_4_N_4096(N,tab2);
fun_inverse_bits_radix_4(N,tab2);
///////////////////////////////////////////////////////////
time2=diffclock( start, clock() );
cout<<"frequency Hz radix-4 real()"<<endl;
system("pause");
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab2[j].real()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
cout<<"frequency Hz radix-4 imag()"<<endl;
system("pause");
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab2[j].imag()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
cout<<"frequency Hz DFT real()"<<endl;
system("pause");
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab3[j].real()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
cout<<"frequency Hz DFT imag()"<<endl;
system("pause");
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab3[j].imag()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
cout<<"if radix-4 == DFT tab2[j].real(): "<<endl;system("pause");
for(int j=0;j<N;j++)
{
if(((tab3[j].real()-tab2[j].real()>=-0.03)&&(tab3[j].real()-tab2[j].real()<=0.03)))
{
cout.precision(4);
cout<<round(tab2[j].real()*1000)/1000<<" ";//system("pause");
}
else {
cout<<-1<<" ........ ";
}
}
system("pause");
cout<<endl;
/////////////////////////////////////////////////////////////////
fun_inverse_fourier_transform_FFT_radix_4_N_4096(N,tab2);
fun_inverse_bits_radix_4(N,tab2);
////////////////////////////////////////////////////////////////
cout<<"inverse/signal= real()"<<endl;
system("pause");
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab2[j].real()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
cout<<"inverse/signal= imag()"<<endl;
system("pause");
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab2[j].imag()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
cout<<endl;
system("pause");
return 0;
}
//////////////////////////////////////////////
void fun_inverse_bits_radix_4(int N,std::complex<double> tab[])
{
}
///////////////////////////////////////////////////
void fun_fourier_transform_DFT_method5_full_complex(int N,std::complex<double> tab[])
{
const double pi=3.141592653589793238462;
std::complex<double> tab2[4096]={}; // tab2[]==N
std::complex<double> w[1]={{1,1}};
double zmienna1=2*pi/(float)N;
double fi2=fi;
for (int i=0;i<N;i++)
{
for(int j=0;j<N;j++)
{
//complex number method:
w[0].real()=cos(i*j*zmienna1+fi2);
w[0].imag()=(-sin(i*j*zmienna1+fi2));
tab2[i]=tab2[i]+tab[j]*w[0];
}
}
for(int j=0;j<N;j++)
{
tab[j].real() =tab2[j].real()*2/N;
tab[j].imag() =tab2[j].imag()*2/N;
}
}
//////////////////
void fun_fourier_transform_FFT_radix_4_N_4096(int N,std::complex<double> tab[])
{
const double pi=3.141592653589793238462;
std::complex<double> w1[1]={{1,0}};
std::complex<double> w2[1]={{1,0}};
std::complex<double> w3[1]={{1,0}};
std::complex<double> w4[1]={{1,0}};
std::complex<double> w5[1]={{1,0}};
std::complex<double> w6[1]={{1,0}};
std::complex<double> tmp1,tmp2,tmp3,tmp4;
std::complex<double> tmp10,tmp20,tmp30,tmp40;
int nr1=0,nr2=0,nr3=0,nr4=0,nr5=0;;
int nb_stages=0,rx4=0;
double tmp5;
int increment=0;
int nn=0;
w5[0].real()=0;
w5[0].imag()=-1;
w6[0].real()=0;
w6[0].imag()=1;
tmp5=2*pi/(N/1);
rx4=4;//radix-4
nn=N;
for(int i=0;i<100;i++)
{
nn=(float)nn/(float)rx4;
if(nn>=1.0)
{
nb_stages++;
}
}
//stage 1
for(int i=0;i<(N/rx4);i++)
{
w1[0].real()=cos(0*tmp5);
w1[0].imag()=-sin(0*tmp5);
w2[0].real()=cos(0*tmp5);
w2[0].imag()=-sin(0*tmp5);
w3[0].real()=cos(0*tmp5);
w3[0].imag()=-sin(0*tmp5);
w4[0].real()=cos(0*tmp5);
w4[0].imag()=-sin(0*tmp5);
tmp1=w1[0]*tab[i+0];
tmp2=w2[0]*tab[i+N/4];
tmp3=w3[0]*tab[i+N/2];
tmp4=w4[0]*tab[i+3*N/4];
//radix-4
tmp10=tmp1+tmp2+ tmp3+tmp4;
tmp20=tmp1-tmp3+w5[0]*(tmp2-tmp4);
tmp30=tmp1-tmp2+ tmp3-tmp4;
tmp40=tmp1-tmp3+w6[0]*(tmp2-tmp4);
tab[i] =tmp10;
tab[i+N/4] =tmp20;
tab[i+N/2] =tmp30;
tab[i+3*N/4] =tmp40;
}
/////////////////////////////////////////////////////////////////////////////////
increment=0;
for(int stg=1;stg<nb_stages;stg++)
{
nr1=pow(rx4,0+increment);
nr2=pow(rx4,1+increment);
nr3=pow(rx4,2+increment);
nr4=pow(rx4,(nb_stages-2-increment));
nr5=pow(rx4,0+increment);
for(int m=0;m<nr5;m++)//stage 2
{
for(int i=0;i<rx4;i++)
{
for(int j=0;j<nr4;j++)
{
w1[0].real()= cos((nr5*0*i*(j+nr4*0)+nr5*1*i*j)*tmp5);
w1[0].imag()=-sin((nr5*0*i*(j+nr4*0)+nr5*1*i*j)*tmp5);
w2[0].real()= cos((nr5*1*i*(j+nr4*1)+nr5*0*i*j)*tmp5);
w2[0].imag()=-sin((nr5*1*i*(j+nr4*1)+nr5*0*i*j)*tmp5);
w3[0].real()= cos((nr5*2*i*(j+nr4*1)-nr5*1*i*j)*tmp5);
w3[0].imag()=-sin((nr5*2*i*(j+nr4*1)-nr5*1*i*j)*tmp5);
w4[0].real()= cos((nr5*3*i*(j+nr4*1)-nr5*2*i*j)*tmp5);
w4[0].imag()=-sin((nr5*3*i*(j+nr4*1)-nr5*2*i*j)*tmp5);
tmp1=w1[0]*tab[0*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j];
tmp2=w2[0]*tab[1*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j];
tmp3=w3[0]*tab[2*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j];
tmp4=w4[0]*tab[3*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j];
//radix-4
tmp10=tmp1+tmp2+ tmp3+tmp4;
tmp20=tmp1-tmp3+w5[0]*(tmp2-tmp4);
tmp30=tmp1-tmp2+ tmp3-tmp4;
tmp40=tmp1-tmp3+w6[0]*(tmp2-tmp4);
tab[0*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j]=tmp10;
tab[1*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j]=tmp20;
tab[2*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j]=tmp30;
tab[3*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j]=tmp40;
}
}
}
increment++;
}
////////////////////////////////////////////////////////////////////////////////
for(int j=0;j<N;j++)
{
tab[j].real() =tab[j].real()*2/N;
tab[j].imag() =tab[j].imag()*2/N;
}
}
////////////////////////////////
void fun_inverse_fourier_transform_FFT_radix_4_N_4096(int N,std::complex<double> tab[])
{
const double pi=3.141592653589793238462;
std::complex<double> w1[1]={{1,0}};
std::complex<double> w2[1]={{1,0}};
std::complex<double> w3[1]={{1,0}};
std::complex<double> w4[1]={{1,0}};
std::complex<double> w5[1]={{1,0}};
std::complex<double> w6[1]={{1,0}};
std::complex<double> tmp1,tmp2,tmp3,tmp4;
std::complex<double> tmp10,tmp20,tmp30,tmp40;
int nr1=0,nr2=0,nr3=0,nr4=0,nr5=0;;
int nb_stages=0,rx4=0;
double tmp5;
int increment=0;
int nn=0;
w5[0].real()=0;
w5[0].imag()=1;
w6[0].real()=0;
w6[0].imag()=-1;
tmp5=2*pi/(N/1);
rx4=4;//radix-4
nn=N;
for(int i=0;i<100;i++)
{
nn=(float)nn/(float)rx4;
if(nn>=1.0)
{
nb_stages++;
}
}
//stage 1
for(int i=0;i<(N/rx4);i++)
{
w1[0].real()=cos(0*tmp5);
w1[0].imag()= sin(0*tmp5);
w2[0].real()=cos(0*tmp5);
w2[0].imag()= sin(0*tmp5);
w3[0].real()=cos(0*tmp5);
w3[0].imag()= sin(0*tmp5);
w4[0].real()=cos(0*tmp5);
w4[0].imag()= sin(0*tmp5);
tmp1=w1[0]*tab[i+0];
tmp2=w2[0]*tab[i+N/4];
tmp3=w3[0]*tab[i+N/2];
tmp4=w4[0]*tab[i+3*N/4];
//radix-4
tmp10=tmp1+tmp2+ tmp3+tmp4;
tmp20=tmp1-tmp3+w5[0]*(tmp2-tmp4);
tmp30=tmp1-tmp2+ tmp3-tmp4;
tmp40=tmp1-tmp3+w6[0]*(tmp2-tmp4);
tab[i] =tmp10;
tab[i+N/4] =tmp20;
tab[i+N/2] =tmp30;
tab[i+3*N/4] =tmp40;
}
/////////////////////////////////////////////////////////////////////////////////
increment=0;
for(int stg=1;stg<nb_stages;stg++)
{
nr1=pow(rx4,0+increment);
nr2=pow(rx4,1+increment);
nr3=pow(rx4,2+increment);
nr4=pow(rx4,(nb_stages-2-increment));
nr5=pow(rx4,0+increment);
for(int m=0;m<nr5;m++)//stage 2
{
for(int i=0;i<rx4;i++)
{
for(int j=0;j<nr4;j++)
{
w1[0].real()= cos((nr5*0*i*(j+nr4*0)+nr5*1*i*j)*tmp5);
w1[0].imag()= sin((nr5*0*i*(j+nr4*0)+nr5*1*i*j)*tmp5);
w2[0].real()= cos((nr5*1*i*(j+nr4*1)+nr5*0*i*j)*tmp5);
w2[0].imag()= sin((nr5*1*i*(j+nr4*1)+nr5*0*i*j)*tmp5);
w3[0].real()= cos((nr5*2*i*(j+nr4*1)-nr5*1*i*j)*tmp5);
w3[0].imag()= sin((nr5*2*i*(j+nr4*1)-nr5*1*i*j)*tmp5);
w4[0].real()= cos((nr5*3*i*(j+nr4*1)-nr5*2*i*j)*tmp5);
w4[0].imag()= sin((nr5*3*i*(j+nr4*1)-nr5*2*i*j)*tmp5);
tmp1=w1[0]*tab[0*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j];
tmp2=w2[0]*tab[1*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j];
tmp3=w3[0]*tab[2*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j];
tmp4=w4[0]*tab[3*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j];
//radix-4
tmp10=tmp1+tmp2+ tmp3+tmp4;
tmp20=tmp1-tmp3+w5[0]*(tmp2-tmp4);
tmp30=tmp1-tmp2+ tmp3-tmp4;
tmp40=tmp1-tmp3+w6[0]*(tmp2-tmp4);
tab[0*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j]=tmp10;
tab[1*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j]=tmp20;
tab[2*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j]=tmp30;
tab[3*N/(nr3)+N/(nr2)*i+N/(nr1)*m+j]=tmp40;
}
}
}
increment++;
}
/////////////////////////////////////////////////////////////
for(int j=0;j<N;j++)
{
tab[j].real() =tab[j].real()*0.5;
tab[j].imag() =tab[j].imag()*0.5;
}
}
//////////////////
//this is new in that method:
//when you want to have equal results that are in false modificator in normal FFT then change this:
/*
fun_fourier_transform_FFT_radix_4_N_256_official
{
for(int j=0;j<N;j++)
{
tab[j].real() =tab[j].real()*2/N;
tab[j].imag() =tab[j].imag()*2/N;
}
}
//and:
fun_inverse_fourier_transform_FFT_radix_4_N_256_official
{
for(int j=0;j<N;j++)
{
tab[j].real() =tab[j].real()*0.5;
tab[j].imag() =tab[j].imag()*0.5;
}
}
//for official modificator that is only in inverse FFT:
fun_fourier_transform_FFT_radix_4_N_256_official
{
}
fun_inverse_fourier_transform_FFT_radix_4_N_256_official
{
for(int i=0;i<N;i++)
{
tablica1[0][i]=tablica1[0][i]*1/(float)N;
tablica1[1][i]=tablica1[1][i]*1/(float)N;
}
}
*/
//haven't try it with other function that cos(x)+jsin(x)=sin(x+pi/2)+jsin(x)
czwartek, 13 kwietnia 2017
fast inverse fourier transform iFFT radix-4 for N=1024 algorithm c++ source code implementation
//source:
//https://www.google.ch/patents/US6957241
//http://www.google.ch/patents/US20020083107
//https://www.beechwood.eu/fft-implementation-r2-dit-r4-dif-r8-dif/
//http://www.cmlab.csie.ntu.edu.tw/cml/dsp/training/coding/transform/fft.html
//http://dsp.stackexchange.com/questions/3481/radix-4-fft-implementation
//author marcin matysek (r)ewertyn.PL
//fast inverse fourier transform iFFT radix-4 for N=1024 algorithm c++ source code implementation
//szybka odwrotna transformacja fouriera iFFT radix-4 dla N=1024 algorytm c++ kod źródłowy implementacja
#include <iostream>
#include "conio.h"
#include <stdlib.h>
#include <math.h>
#include <cmath>
#include <time.h>
#include <complex>
#include <fstream>
using namespace std;
//complex number method:
void fun_inverse_bits_radix_4(int N,std::complex<double> tab[]);
void fun_fourier_transform_FFT_radix_4_N_1024(int N,std::complex<double> tab[]);
void fun_inverse_fourier_transform_FFT_radix_4_N_1024(int N,std::complex<double> tab[]);
void fun_fourier_transform_DFT_method5_full_complex(int N,std::complex<double> tab[]);
int fi=0;
static double diffclock(clock_t clock2,clock_t clock1)
{
double diffticks=clock1-clock2;
double diffms=(diffticks)/(CLOCKS_PER_SEC/1000);
return diffms;
}
int main()
{
int N;
//if N==period of signal in table tab[] then resolution = 1 Hz
N=1024;
std::complex<double> tab2[4096]={};
std::complex<double> tab3[4096]={};
for(int i=0;i<N;i++)
{
tab2[i].real()=i+1;
tab2[i].imag()=N+i+1;
tab3[i].real()=i+1;
tab3[i].imag()=N+i+1;
}
double time2;
double zmienna=0;
cout<<"signal 1="<<endl;
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab2[j].real()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab2[j].imag()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
cout<<"signal 2="<<endl;
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab3[j].real()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab3[j].imag()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
system("pause");
clock_t start = clock();
fun_fourier_transform_DFT_method5_full_complex(N,tab3);
//////////////////////////////////////////////////////////
fun_fourier_transform_FFT_radix_4_N_1024(N,tab2);
fun_inverse_bits_radix_4(N,tab2);
///////////////////////////////////////////////////////////
time2=diffclock( start, clock() );
cout<<"frequency Hz radix-4"<<endl;
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab2[j].real()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab2[j].imag()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
cout<<"frequency Hz DFT"<<endl;
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab3[j].real()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab3[j].imag()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
cout<<"if radix-4 == DFT tab2[j].real(): "<<endl;system("pause");
for(int j=0;j<N;j++)
{
if(((tab3[j].real()-tab2[j].real()>=-0.03)&&(tab3[j].real()-tab2[j].real()<=0.03)))
{
cout.precision(4);
cout<<round(tab2[j].real()*1000)/1000<<" ";//system("pause");
}
else {
cout<<-1<<" ........ ";
}
}
system("pause");
cout<<endl;
/////////////////////////////////////////////////////////////////
fun_inverse_fourier_transform_FFT_radix_4_N_1024(N,tab2);
fun_inverse_bits_radix_4(N,tab2);
////////////////////////////////////////////////////////////////
cout<<"inverse/signal="<<endl;
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab2[j].real()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab2[j].imag()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
cout<<endl;
system("pause");
return 0;
}
//////////////////////////////////////////////
void fun_inverse_bits_radix_4(int N,std::complex<double> tab[])
{
}
///////////////////////////////////////////////////
void fun_fourier_transform_DFT_method5_full_complex(int N,std::complex<double> tab[])
{
const double pi=3.141592653589793238462;
std::complex<double> tab2[4096]={}; // tab2[]==N
std::complex<double> w[1]={{1,1}};
double zmienna1=2*pi/(float)N;
double fi2=fi;
for (int i=0;i<N;i++)
{
for(int j=0;j<N;j++)
{
//complex number method:
w[0].real()=cos(i*j*zmienna1+fi2);
w[0].imag()=(-sin(i*j*zmienna1+fi2));
tab2[i]=tab2[i]+tab[j]*w[0];
}
}
for(int j=0;j<N;j++)
{
tab[j].real() =tab2[j].real()*2/N;
tab[j].imag() =tab2[j].imag()*2/N;
}
}
//////////////////
void fun_fourier_transform_FFT_radix_4_N_1024(int N,std::complex<double> tab[])
{
const double pi=3.141592653589793238462;
std::complex<double> tab2[4096]={}; // tab2[]==N
std::complex<double> w1[1]={{1,0}};
std::complex<double> w2[1]={{1,0}};
std::complex<double> w3[1]={{1,0}};
std::complex<double> w4[1]={{1,0}};
std::complex<double> w5[1]={{1,0}};
std::complex<double> w6[1]={{1,0}};
std::complex<double> tmp1,tmp2,tmp3,tmp4;
double tmp5;
w5[0].real()=0;
w5[0].imag()=-1;
w6[0].real()=0;
w6[0].imag()=1;
tmp5=2*pi/(N/1);
//stage 1
for(int i=0;i<(N/4);i++)//256
{
w1[0].real()=cos(0*tmp5);
w1[0].imag()=-sin(0*tmp5);
w2[0].real()=cos(0*tmp5);
w2[0].imag()=-sin(0*tmp5);
w3[0].real()=cos(0*tmp5);
w3[0].imag()=-sin(0*tmp5);
w4[0].real()=cos(0*tmp5);
w4[0].imag()=-sin(0*tmp5);
tmp1=w1[0]*tab[i+0];
tmp2=w2[0]*tab[i+N/4];
tmp3=w3[0]*tab[i+N/2];
tmp4=w4[0]*tab[i+3*N/4];
//radix-4
tab2[i] =tmp1+tmp2+tmp3+tmp4;
tab2[i+N/4] =tmp1-tmp3+w5[0]*(tmp2-tmp4);
tab2[i+N/2] =tmp1-tmp2+tmp3-tmp4;
tab2[i+3*N/4] =tmp1-tmp3+w6[0]*(tmp2-tmp4);
}
/////////////////////////////////////////////////////////////////////////////////
for(int m=0;m<1;m++)//stage 2
{
for(int i=0;i<4;i++)
{
for(int j=0;j<4*4*4;j++)
{
w1[0].real()= cos((1*0*i*(j+4*4*4*0)+1*1*i*j)*tmp5);
w1[0].imag()=-sin((1*0*i*(j+4*4*4*0)+1*1*i*j)*tmp5);
w2[0].real()= cos((1*1*i*(j+4*4*4*1)+1*0*i*j)*tmp5);
w2[0].imag()=-sin((1*1*i*(j+4*4*4*1)+1*0*i*j)*tmp5);
w3[0].real()= cos((1*2*i*(j+4*4*4*1)-1*1*i*j)*tmp5);
w3[0].imag()=-sin((1*2*i*(j+4*4*4*1)-1*1*i*j)*tmp5);
w4[0].real()= cos((1*3*i*(j+4*4*4*1)-1*2*i*j)*tmp5);
w4[0].imag()=-sin((1*3*i*(j+4*4*4*1)-1*2*i*j)*tmp5);
tmp1=w1[0]*tab2[0*N/(4*4)+N/(4)*i+N/(1)*m+j];
tmp2=w2[0]*tab2[1*N/(4*4)+N/(4)*i+N/(1)*m+j];
tmp3=w3[0]*tab2[2*N/(4*4)+N/(4)*i+N/(1)*m+j];
tmp4=w4[0]*tab2[3*N/(4*4)+N/(4)*i+N/(1)*m+j];
//radix-4
tab[0*N/(4*4)+N/(4)*i+N/(1)*m+j]=tmp1+tmp2+ tmp3+tmp4;
tab[1*N/(4*4)+N/(4)*i+N/(1)*m+j]=tmp1-tmp3+w5[0]*(tmp2-tmp4);
tab[2*N/(4*4)+N/(4)*i+N/(1)*m+j]=tmp1-tmp2+ tmp3-tmp4;
tab[3*N/(4*4)+N/(4)*i+N/(1)*m+j]=tmp1-tmp3+w6[0]*(tmp2-tmp4);
}
}
}
////////////////////////////////////////////////////////////////////////////////
for(int m=0;m<4;m++)//stage 3
{
for(int i=0;i<4;i++)
{
for(int j=0;j<4*4;j++)
{
w1[0].real()= cos((4*0*i*(j+4*4*0)+4*1*i*j)*tmp5);
w1[0].imag()=-sin((4*0*i*(j+4*4*0)+4*1*i*j)*tmp5);
w2[0].real()= cos((4*1*i*(j+4*4*1)+4*0*i*j)*tmp5);
w2[0].imag()=-sin((4*1*i*(j+4*4*1)+4*0*i*j)*tmp5);
w3[0].real()= cos((4*2*i*(j+4*4*1)-4*1*i*j)*tmp5);
w3[0].imag()=-sin((4*2*i*(j+4*4*1)-4*1*i*j)*tmp5);
w4[0].real()= cos((4*3*i*(j+4*4*1)-4*2*i*j)*tmp5);
w4[0].imag()=-sin((4*3*i*(j+4*4*1)-4*2*i*j)*tmp5);
tmp1=w1[0]*tab[0*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j];
tmp2=w2[0]*tab[1*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j];
tmp3=w3[0]*tab[2*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j];
tmp4=w4[0]*tab[3*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j];
//radix-4
tab2[0*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j]=tmp1+tmp2+ tmp3+tmp4;
tab2[1*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j]=tmp1-tmp3+w5[0]*(tmp2-tmp4);
tab2[2*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j]=tmp1-tmp2+ tmp3-tmp4;
tab2[3*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j]=tmp1-tmp3+w6[0]*(tmp2-tmp4);
}
}
}
////////////////////////////////////////////////////////////////////////////////
for(int m=0;m<4*4;m++)//stage 4
{
for(int i=0;i<4;i++)
{
for(int j=0;j<4;j++)
{
w1[0].real()= cos((4*4*0*i*(j+4*0)+4*4*1*i*j)*tmp5);
w1[0].imag()=-sin((4*4*0*i*(j+4*0)+4*4*1*i*j)*tmp5);
w2[0].real()= cos((4*4*1*i*(j+4*1)+4*4*0*i*j)*tmp5);
w2[0].imag()=-sin((4*4*1*i*(j+4*1)+4*4*0*i*j)*tmp5);
w3[0].real()= cos((4*4*2*i*(j+4*1)-4*4*1*i*j)*tmp5);
w3[0].imag()=-sin((4*4*2*i*(j+4*1)-4*4*1*i*j)*tmp5);
w4[0].real()= cos((4*4*3*i*(j+4*1)-4*4*2*i*j)*tmp5);
w4[0].imag()=-sin((4*4*3*i*(j+4*1)-4*4*2*i*j)*tmp5);
tmp1=w1[0]*tab2[0*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j];
tmp2=w2[0]*tab2[1*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j];
tmp3=w3[0]*tab2[2*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j];
tmp4=w4[0]*tab2[3*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j];
//radix-4
tab[0*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j]=tmp1+tmp2+ tmp3+tmp4;
tab[1*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j]=tmp1-tmp3+w5[0]*(tmp2-tmp4);
tab[2*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j]=tmp1-tmp2+ tmp3-tmp4;
tab[3*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j]=tmp1-tmp3+w6[0]*(tmp2-tmp4);
}
}
}
///////////////////////////////////////////////////////////////////////////////
for(int m=0;m<4*4*4;m++)//stage 5
{
for(int i=0;i<4;i++)
{
for(int j=0;j<1;j++)
{
w1[0].real()= cos((4*4*4*0*i*(j+1*0)+4*4*4*1*i*j)*tmp5);
w1[0].imag()=-sin((4*4*4*0*i*(j+1*0)+4*4*4*1*i*j)*tmp5);
w2[0].real()= cos((4*4*4*1*i*(j+1*1)+4*4*4*0*i*j)*tmp5);
w2[0].imag()=-sin((4*4*4*1*i*(j+1*1)+4*4*4*0*i*j)*tmp5);
w3[0].real()= cos((4*4*4*2*i*(j+1*1)-4*4*4*1*i*j)*tmp5);
w3[0].imag()=-sin((4*4*4*2*i*(j+1*1)-4*4*4*1*i*j)*tmp5);
w4[0].real()= cos((4*4*4*3*i*(j+1*1)-4*4*4*2*i*j)*tmp5);
w4[0].imag()=-sin((4*4*4*3*i*(j+1*1)-4*4*4*2*i*j)*tmp5);
tmp1=w1[0]*tab[0*N/(4*4*4*4*4)+N/(4*4*4*4)*i+N/(4*4*4)*m+j];
tmp2=w2[0]*tab[1*N/(4*4*4*4*4)+N/(4*4*4*4)*i+N/(4*4*4)*m+j];
tmp3=w3[0]*tab[2*N/(4*4*4*4*4)+N/(4*4*4*4)*i+N/(4*4*4)*m+j];
tmp4=w4[0]*tab[3*N/(4*4*4*4*4)+N/(4*4*4*4)*i+N/(4*4*4)*m+j];
//radix-4
tab2[0*N/(4*4*4*4*4)+N/(4*4*4*4)*i+N/(4*4*4)*m+j]=tmp1+tmp2+ tmp3+tmp4;
tab2[1*N/(4*4*4*4*4)+N/(4*4*4*4)*i+N/(4*4*4)*m+j]=tmp1-tmp3+w5[0]*(tmp2-tmp4);
tab2[2*N/(4*4*4*4*4)+N/(4*4*4*4)*i+N/(4*4*4)*m+j]=tmp1-tmp2+ tmp3-tmp4;
tab2[3*N/(4*4*4*4*4)+N/(4*4*4*4)*i+N/(4*4*4)*m+j]=tmp1-tmp3+w6[0]*(tmp2-tmp4);
}
}
}
for(int j=0;j<N;j++)
{
tab[j].real() =tab2[j].real()*2/N;
tab[j].imag() =tab2[j].imag()*2/N;
}
}
//////////////////
void fun_inverse_fourier_transform_FFT_radix_4_N_1024(int N,std::complex<double> tab[])
{
const double pi=3.141592653589793238462;
std::complex<double> tab2[4096]={}; // tab2[]==N
std::complex<double> w1[1]={{1,0}};
std::complex<double> w2[1]={{1,0}};
std::complex<double> w3[1]={{1,0}};
std::complex<double> w4[1]={{1,0}};
std::complex<double> w5[1]={{1,0}};
std::complex<double> w6[1]={{1,0}};
std::complex<double> tmp1,tmp2,tmp3,tmp4;
double tmp5;
w5[0].real()=0;
w5[0].imag()=1;
w6[0].real()=0;
w6[0].imag()=-1;
tmp5=2*pi/(N/1);
//stage 1
for(int i=0;i<(N/4);i++)//256
{
w1[0].real()=cos(0*tmp5);
w1[0].imag()=sin(0*tmp5);
w2[0].real()=cos(0*tmp5);
w2[0].imag()=sin(0*tmp5);
w3[0].real()=cos(0*tmp5);
w3[0].imag()=sin(0*tmp5);
w4[0].real()=cos(0*tmp5);
w4[0].imag()=sin(0*tmp5);
tmp1=w1[0]*tab[i+0];
tmp2=w2[0]*tab[i+N/4];
tmp3=w3[0]*tab[i+N/2];
tmp4=w4[0]*tab[i+3*N/4];
//radix-4
tab2[i] =tmp1+tmp2+tmp3+tmp4;
tab2[i+N/4] =tmp1-tmp3+w5[0]*(tmp2-tmp4);
tab2[i+N/2] =tmp1-tmp2+tmp3-tmp4;
tab2[i+3*N/4] =tmp1-tmp3+w6[0]*(tmp2-tmp4);
}
/////////////////////////////////////////////////////////////////////////////////
for(int m=0;m<1;m++)//stage 2
{
for(int i=0;i<4;i++)
{
for(int j=0;j<4*4*4;j++)
{
w1[0].real()= cos((1*0*i*(j+4*4*4*0)+1*1*i*j)*tmp5);
w1[0].imag()=sin((1*0*i*(j+4*4*4*0)+1*1*i*j)*tmp5);
w2[0].real()= cos((1*1*i*(j+4*4*4*1)+1*0*i*j)*tmp5);
w2[0].imag()=sin((1*1*i*(j+4*4*4*1)+1*0*i*j)*tmp5);
w3[0].real()= cos((1*2*i*(j+4*4*4*1)-1*1*i*j)*tmp5);
w3[0].imag()=sin((1*2*i*(j+4*4*4*1)-1*1*i*j)*tmp5);
w4[0].real()= cos((1*3*i*(j+4*4*4*1)-1*2*i*j)*tmp5);
w4[0].imag()=sin((1*3*i*(j+4*4*4*1)-1*2*i*j)*tmp5);
tmp1=w1[0]*tab2[0*N/(4*4)+N/(4)*i+N/(1)*m+j];
tmp2=w2[0]*tab2[1*N/(4*4)+N/(4)*i+N/(1)*m+j];
tmp3=w3[0]*tab2[2*N/(4*4)+N/(4)*i+N/(1)*m+j];
tmp4=w4[0]*tab2[3*N/(4*4)+N/(4)*i+N/(1)*m+j];
//radix-4
tab[0*N/(4*4)+N/(4)*i+N/(1)*m+j]=tmp1+tmp2+ tmp3+tmp4;
tab[1*N/(4*4)+N/(4)*i+N/(1)*m+j]=tmp1-tmp3+w5[0]*(tmp2-tmp4);
tab[2*N/(4*4)+N/(4)*i+N/(1)*m+j]=tmp1-tmp2+ tmp3-tmp4;
tab[3*N/(4*4)+N/(4)*i+N/(1)*m+j]=tmp1-tmp3+w6[0]*(tmp2-tmp4);
}
}
}
////////////////////////////////////////////////////////////////////////////////
for(int m=0;m<4;m++)//stage 3
{
for(int i=0;i<4;i++)
{
for(int j=0;j<4*4;j++)
{
w1[0].real()= cos((4*0*i*(j+4*4*0)+4*1*i*j)*tmp5);
w1[0].imag()=sin((4*0*i*(j+4*4*0)+4*1*i*j)*tmp5);
w2[0].real()= cos((4*1*i*(j+4*4*1)+4*0*i*j)*tmp5);
w2[0].imag()=sin((4*1*i*(j+4*4*1)+4*0*i*j)*tmp5);
w3[0].real()= cos((4*2*i*(j+4*4*1)-4*1*i*j)*tmp5);
w3[0].imag()=sin((4*2*i*(j+4*4*1)-4*1*i*j)*tmp5);
w4[0].real()= cos((4*3*i*(j+4*4*1)-4*2*i*j)*tmp5);
w4[0].imag()=sin((4*3*i*(j+4*4*1)-4*2*i*j)*tmp5);
tmp1=w1[0]*tab[0*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j];
tmp2=w2[0]*tab[1*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j];
tmp3=w3[0]*tab[2*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j];
tmp4=w4[0]*tab[3*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j];
//radix-4
tab2[0*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j]=tmp1+tmp2+ tmp3+tmp4;
tab2[1*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j]=tmp1-tmp3+w5[0]*(tmp2-tmp4);
tab2[2*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j]=tmp1-tmp2+ tmp3-tmp4;
tab2[3*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j]=tmp1-tmp3+w6[0]*(tmp2-tmp4);
}
}
}
////////////////////////////////////////////////////////////////////////////////
for(int m=0;m<4*4;m++)//stage 4
{
for(int i=0;i<4;i++)
{
for(int j=0;j<4;j++)
{
w1[0].real()= cos((4*4*0*i*(j+4*0)+4*4*1*i*j)*tmp5);
w1[0].imag()=sin((4*4*0*i*(j+4*0)+4*4*1*i*j)*tmp5);
w2[0].real()= cos((4*4*1*i*(j+4*1)+4*4*0*i*j)*tmp5);
w2[0].imag()=sin((4*4*1*i*(j+4*1)+4*4*0*i*j)*tmp5);
w3[0].real()=cos((4*4*2*i*(j+4*1)-4*4*1*i*j)*tmp5);
w3[0].imag()=sin((4*4*2*i*(j+4*1)-4*4*1*i*j)*tmp5);
w4[0].real()= cos((4*4*3*i*(j+4*1)-4*4*2*i*j)*tmp5);
w4[0].imag()=sin((4*4*3*i*(j+4*1)-4*4*2*i*j)*tmp5);
tmp1=w1[0]*tab2[0*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j];
tmp2=w2[0]*tab2[1*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j];
tmp3=w3[0]*tab2[2*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j];
tmp4=w4[0]*tab2[3*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j];
//radix-4
tab[0*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j]=tmp1+tmp2+ tmp3+tmp4;
tab[1*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j]=tmp1-tmp3+w5[0]*(tmp2-tmp4);
tab[2*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j]=tmp1-tmp2+ tmp3-tmp4;
tab[3*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j]=tmp1-tmp3+w6[0]*(tmp2-tmp4);
}
}
}
///////////////////////////////////////////////////////////////////////////////
for(int m=0;m<4*4*4;m++)//stage 5
{
for(int i=0;i<4;i++)
{
for(int j=0;j<1;j++)
{
w1[0].real()= cos((4*4*4*0*i*(j+1*0)+4*4*4*1*i*j)*tmp5);
w1[0].imag()=sin((4*4*4*0*i*(j+1*0)+4*4*4*1*i*j)*tmp5);
w2[0].real()= cos((4*4*4*1*i*(j+1*1)+4*4*4*0*i*j)*tmp5);
w2[0].imag()=sin((4*4*4*1*i*(j+1*1)+4*4*4*0*i*j)*tmp5);
w3[0].real()= cos((4*4*4*2*i*(j+1*1)-4*4*4*1*i*j)*tmp5);
w3[0].imag()=sin((4*4*4*2*i*(j+1*1)-4*4*4*1*i*j)*tmp5);
w4[0].real()= cos((4*4*4*3*i*(j+1*1)-4*4*4*2*i*j)*tmp5);
w4[0].imag()=sin((4*4*4*3*i*(j+1*1)-4*4*4*2*i*j)*tmp5);
tmp1=w1[0]*tab[0*N/(4*4*4*4*4)+N/(4*4*4*4)*i+N/(4*4*4)*m+j];
tmp2=w2[0]*tab[1*N/(4*4*4*4*4)+N/(4*4*4*4)*i+N/(4*4*4)*m+j];
tmp3=w3[0]*tab[2*N/(4*4*4*4*4)+N/(4*4*4*4)*i+N/(4*4*4)*m+j];
tmp4=w4[0]*tab[3*N/(4*4*4*4*4)+N/(4*4*4*4)*i+N/(4*4*4)*m+j];
//radix-4
tab2[0*N/(4*4*4*4*4)+N/(4*4*4*4)*i+N/(4*4*4)*m+j]=tmp1+tmp2+ tmp3+tmp4;
tab2[1*N/(4*4*4*4*4)+N/(4*4*4*4)*i+N/(4*4*4)*m+j]=tmp1-tmp3+w5[0]*(tmp2-tmp4);
tab2[2*N/(4*4*4*4*4)+N/(4*4*4*4)*i+N/(4*4*4)*m+j]=tmp1-tmp2+ tmp3-tmp4;
tab2[3*N/(4*4*4*4*4)+N/(4*4*4*4)*i+N/(4*4*4)*m+j]=tmp1-tmp3+w6[0]*(tmp2-tmp4);
}
}
}
for(int j=0;j<N;j++)
{
tab[j].real() =tab2[j].real()*0.5;
tab[j].imag() =tab2[j].imag()*0.5;
}
}
//this is new in that method:
//when you want to have equal results that are in false modificator in normal FFT then change this:
/*
fun_fourier_transform_FFT_radix_4_N_256_official
{
for(int j=0;j<N;j++)
{
tab[j].real() =tab[j].real()*2/N;
tab[j].imag() =tab[j].imag()*2/N;
}
}
//and:
fun_inverse_fourier_transform_FFT_radix_4_N_256_official
{
for(int j=0;j<N;j++)
{
tab[j].real() =tab[j].real()*0.5;
tab[j].imag() =tab[j].imag()*0.5;
}
}
//for official modificator that is only in inverse FFT:
fun_fourier_transform_FFT_radix_4_N_256_official
{
}
fun_inverse_fourier_transform_FFT_radix_4_N_256_official
{
for(int i=0;i<N;i++)
{
tablica1[0][i]=tablica1[0][i]*1/(float)N;
tablica1[1][i]=tablica1[1][i]*1/(float)N;
}
}
*/
//haven't try it with other function that cos(x)+jsin(x)=sin(x+pi/2)+jsin(x)
fast fourier transform FFT radix-4 for N=1024 algorithm c++ source code implementation
//source:
//https://www.google.ch/patents/US6957241
//http://www.google.ch/patents/US20020083107
//https://www.beechwood.eu/fft-implementation-r2-dit-r4-dif-r8-dif/
//http://www.cmlab.csie.ntu.edu.tw/cml/dsp/training/coding/transform/fft.html
//http://dsp.stackexchange.com/questions/3481/radix-4-fft-implementation
//author marcin matysek (r)ewertyn.PL
//fast fourier transform FFT radix-4 for N=1024 algorithm c++ source code implementation
void fun_fourier_transform_FFT_radix_4_N_1024(int N,std::complex<double> tab[])
{
const double pi=3.141592653589793238462;
std::complex<double> tab2[4096]={}; // tab2[]==N
std::complex<double> w1[1]={{1,0}};
std::complex<double> w2[1]={{1,0}};
std::complex<double> w3[1]={{1,0}};
std::complex<double> w4[1]={{1,0}};
std::complex<double> w5[1]={{1,0}};
std::complex<double> w6[1]={{1,0}};
std::complex<double> tmp1,tmp2,tmp3,tmp4;
double tmp5;
w5[0].real()=0;
w5[0].imag()=-1;
w6[0].real()=0;
w6[0].imag()=1;
tmp5=2*pi/(N/1);
//stage 1
for(int i=0;i<(N/4);i++)//256
{
w1[0].real()=cos(0*tmp5);
w1[0].imag()=-sin(0*tmp5);
w2[0].real()=cos(0*tmp5);
w2[0].imag()=-sin(0*tmp5);
w3[0].real()=cos(0*tmp5);
w3[0].imag()=-sin(0*tmp5);
w4[0].real()=cos(0*tmp5);
w4[0].imag()=-sin(0*tmp5);
tmp1=w1[0]*tab[i+0];
tmp2=w2[0]*tab[i+N/4];
tmp3=w3[0]*tab[i+N/2];
tmp4=w4[0]*tab[i+3*N/4];
//radix-4
tab2[i] =tmp1+tmp2+tmp3+tmp4;
tab2[i+N/4] =tmp1-tmp3+w5[0]*(tmp2-tmp4);
tab2[i+N/2] =tmp1-tmp2+tmp3-tmp4;
tab2[i+3*N/4] =tmp1-tmp3+w6[0]*(tmp2-tmp4);
}
/////////////////////////////////////////////////////////////////////////////////
for(int m=0;m<1;m++)//stage 2
{
for(int i=0;i<4;i++)
{
for(int j=0;j<4*4*4;j++)
{
w1[0].real()= cos((1*0*i*(j+4*4*4*0)+1*1*i*j)*tmp5);
w1[0].imag()=-sin((1*0*i*(j+4*4*4*0)+1*1*i*j)*tmp5);
w2[0].real()= cos((1*1*i*(j+4*4*4*1)+1*0*i*j)*tmp5);
w2[0].imag()=-sin((1*1*i*(j+4*4*4*1)+1*0*i*j)*tmp5);
w3[0].real()= cos((1*2*i*(j+4*4*4*1)-1*1*i*j)*tmp5);
w3[0].imag()=-sin((1*2*i*(j+4*4*4*1)-1*1*i*j)*tmp5);
w4[0].real()= cos((1*3*i*(j+4*4*4*1)-1*2*i*j)*tmp5);
w4[0].imag()=-sin((1*3*i*(j+4*4*4*1)-1*2*i*j)*tmp5);
tmp1=w1[0]*tab2[0*N/(4*4)+N/(4)*i+N/(1)*m+j];
tmp2=w2[0]*tab2[1*N/(4*4)+N/(4)*i+N/(1)*m+j];
tmp3=w3[0]*tab2[2*N/(4*4)+N/(4)*i+N/(1)*m+j];
tmp4=w4[0]*tab2[3*N/(4*4)+N/(4)*i+N/(1)*m+j];
//radix-4
tab[0*N/(4*4)+N/(4)*i+N/(1)*m+j]=tmp1+tmp2+ tmp3+tmp4;
tab[1*N/(4*4)+N/(4)*i+N/(1)*m+j]=tmp1-tmp3+w5[0]*(tmp2-tmp4);
tab[2*N/(4*4)+N/(4)*i+N/(1)*m+j]=tmp1-tmp2+ tmp3-tmp4;
tab[3*N/(4*4)+N/(4)*i+N/(1)*m+j]=tmp1-tmp3+w6[0]*(tmp2-tmp4);
}
}
}
////////////////////////////////////////////////////////////////////////////////
for(int m=0;m<4;m++)//stage 3
{
for(int i=0;i<4;i++)
{
for(int j=0;j<4*4;j++)
{
w1[0].real()= cos((4*0*i*(j+4*4*0)+4*1*i*j)*tmp5);
w1[0].imag()=-sin((4*0*i*(j+4*4*0)+4*1*i*j)*tmp5);
w2[0].real()= cos((4*1*i*(j+4*4*1)+4*0*i*j)*tmp5);
w2[0].imag()=-sin((4*1*i*(j+4*4*1)+4*0*i*j)*tmp5);
w3[0].real()= cos((4*2*i*(j+4*4*1)-4*1*i*j)*tmp5);
w3[0].imag()=-sin((4*2*i*(j+4*4*1)-4*1*i*j)*tmp5);
w4[0].real()= cos((4*3*i*(j+4*4*1)-4*2*i*j)*tmp5);
w4[0].imag()=-sin((4*3*i*(j+4*4*1)-4*2*i*j)*tmp5);
tmp1=w1[0]*tab[0*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j];
tmp2=w2[0]*tab[1*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j];
tmp3=w3[0]*tab[2*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j];
tmp4=w4[0]*tab[3*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j];
//radix-4
tab2[0*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j]=tmp1+tmp2+ tmp3+tmp4;
tab2[1*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j]=tmp1-tmp3+w5[0]*(tmp2-tmp4);
tab2[2*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j]=tmp1-tmp2+ tmp3-tmp4;
tab2[3*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j]=tmp1-tmp3+w6[0]*(tmp2-tmp4);
}
}
}
////////////////////////////////////////////////////////////////////////////////
for(int m=0;m<4*4;m++)//stage 4
{
for(int i=0;i<4;i++)
{
for(int j=0;j<4;j++)
{
w1[0].real()= cos((4*4*0*i*(j+4*0)+4*4*1*i*j)*tmp5);
w1[0].imag()=-sin((4*4*0*i*(j+4*0)+4*4*1*i*j)*tmp5);
w2[0].real()= cos((4*4*1*i*(j+4*1)+4*4*0*i*j)*tmp5);
w2[0].imag()=-sin((4*4*1*i*(j+4*1)+4*4*0*i*j)*tmp5);
w3[0].real()= cos((4*4*2*i*(j+4*1)-4*4*1*i*j)*tmp5);
w3[0].imag()=-sin((4*4*2*i*(j+4*1)-4*4*1*i*j)*tmp5);
w4[0].real()= cos((4*4*3*i*(j+4*1)-4*4*2*i*j)*tmp5);
w4[0].imag()=-sin((4*4*3*i*(j+4*1)-4*4*2*i*j)*tmp5);
tmp1=w1[0]*tab2[0*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j];
tmp2=w2[0]*tab2[1*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j];
tmp3=w3[0]*tab2[2*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j];
tmp4=w4[0]*tab2[3*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j];
//radix-4
tab[0*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j]=tmp1+tmp2+ tmp3+tmp4;
tab[1*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j]=tmp1-tmp3+w5[0]*(tmp2-tmp4);
tab[2*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j]=tmp1-tmp2+ tmp3-tmp4;
tab[3*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j]=tmp1-tmp3+w6[0]*(tmp2-tmp4);
}
}
}
///////////////////////////////////////////////////////////////////////////////
for(int m=0;m<4*4*4;m++)//stage 5
{
for(int i=0;i<4;i++)
{
for(int j=0;j<1;j++)
{
w1[0].real()= cos((4*4*4*0*i*(j+1*0)+4*4*4*1*i*j)*tmp5);
w1[0].imag()=-sin((4*4*4*0*i*(j+1*0)+4*4*4*1*i*j)*tmp5);
w2[0].real()= cos((4*4*4*1*i*(j+1*1)+4*4*4*0*i*j)*tmp5);
w2[0].imag()=-sin((4*4*4*1*i*(j+1*1)+4*4*4*0*i*j)*tmp5);
w3[0].real()= cos((4*4*4*2*i*(j+1*1)-4*4*4*1*i*j)*tmp5);
w3[0].imag()=-sin((4*4*4*2*i*(j+1*1)-4*4*4*1*i*j)*tmp5);
w4[0].real()= cos((4*4*4*3*i*(j+1*1)-4*4*4*2*i*j)*tmp5);
w4[0].imag()=-sin((4*4*4*3*i*(j+1*1)-4*4*4*2*i*j)*tmp5);
tmp1=w1[0]*tab[0*N/(4*4*4*4*4)+N/(4*4*4*4)*i+N/(4*4*4)*m+j];
tmp2=w2[0]*tab[1*N/(4*4*4*4*4)+N/(4*4*4*4)*i+N/(4*4*4)*m+j];
tmp3=w3[0]*tab[2*N/(4*4*4*4*4)+N/(4*4*4*4)*i+N/(4*4*4)*m+j];
tmp4=w4[0]*tab[3*N/(4*4*4*4*4)+N/(4*4*4*4)*i+N/(4*4*4)*m+j];
//radix-4
tab2[0*N/(4*4*4*4*4)+N/(4*4*4*4)*i+N/(4*4*4)*m+j]=tmp1+tmp2+ tmp3+tmp4;
tab2[1*N/(4*4*4*4*4)+N/(4*4*4*4)*i+N/(4*4*4)*m+j]=tmp1-tmp3+w5[0]*(tmp2-tmp4);
tab2[2*N/(4*4*4*4*4)+N/(4*4*4*4)*i+N/(4*4*4)*m+j]=tmp1-tmp2+ tmp3-tmp4;
tab2[3*N/(4*4*4*4*4)+N/(4*4*4*4)*i+N/(4*4*4)*m+j]=tmp1-tmp3+w6[0]*(tmp2-tmp4);
}
}
}
for(int j=0;j<N;j++)
{
tab[j].real() =tab2[j].real();
tab[j].imag() =tab2[j].imag();
}
/*
for(int j=0;j<N;j++)
{
tab[j].real() =tab2[j].real()*2/N;
tab[j].imag() =tab2[j].imag()*2/N;
}
*/
}
///////////////////////////////////////////////
środa, 12 kwietnia 2017
FFT radix-4 multiplier Wn for N=256
//FFT radix-4 multiplier Wn for N=256
//stage 1 FFT radix-4 multiplier Wn for N=256
//////////////////////////////////
//////////////////////////////////
for(int m=0;m<1;m++)//stage 2
{
for(int i=0;i<4;i++)
{
for(int j=0;j<16;j++)
{
tab5[0*N/(4*4)+N/(4)*i+j]=1*0*i*(j+16*0)+1*1*i*j;
tab5[1*N/(4*4)+N/(4)*i+j]=1*1*i*(j+16*1)+1*0*i*j;
tab5[2*N/(4*4)+N/(4)*i+j]=1*2*i*(j+16*1)-1*1*i*j;
tab5[3*N/(4*4)+N/(4)*i+j]=1*3*i*(j+16*1)-1*2*i*j;
}
}
}
//////////////////////////////////
for(int m=0;m<4;m++)//stage 3
{
for(int i=0;i<4;i++)
{
for(int j=0;j<4;j++)
{
tab5[0*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j]=4*0*i*(j+4*0)+4*1*i*j;
tab5[1*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j]=4*1*i*(j+4*1)+4*0*i*j;
tab5[2*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j]=4*2*i*(j+4*1)-4*1*i*j;
tab5[3*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j]=4*3*i*(j+4*1)-4*2*i*j;
}
}
}
//////////////////////////////////
for(int m=0;m<16;m++)//stage 4
{
for(int i=0;i<4;i++)
{
for(int j=0;j<1;j++)
{
tab5[0*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j]=16*0*i*(j+1*0)+16*1*i*j;
tab5[1*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j]=16*1*i*(j+1*1)+16*0*i*j;
tab5[2*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j]=16*2*i*(j+1*1)-16*1*i*j;
tab5[3*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j]=16*3*i*(j+1*1)-16*2*i*j;
}
}
}
/////////////////////////////////
//stage 1 FFT radix-4 multiplier Wn for N=256
//////////////////////////////////
//////////////////////////////////
for(int m=0;m<1;m++)//stage 2
{
for(int i=0;i<4;i++)
{
for(int j=0;j<16;j++)
{
tab5[0*N/(4*4)+N/(4)*i+j]=1*0*i*(j+16*0)+1*1*i*j;
tab5[1*N/(4*4)+N/(4)*i+j]=1*1*i*(j+16*1)+1*0*i*j;
tab5[2*N/(4*4)+N/(4)*i+j]=1*2*i*(j+16*1)-1*1*i*j;
tab5[3*N/(4*4)+N/(4)*i+j]=1*3*i*(j+16*1)-1*2*i*j;
}
}
}
//////////////////////////////////
for(int m=0;m<4;m++)//stage 3
{
for(int i=0;i<4;i++)
{
for(int j=0;j<4;j++)
{
tab5[0*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j]=4*0*i*(j+4*0)+4*1*i*j;
tab5[1*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j]=4*1*i*(j+4*1)+4*0*i*j;
tab5[2*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j]=4*2*i*(j+4*1)-4*1*i*j;
tab5[3*N/(4*4*4)+N/(4*4)*i+N/(4)*m+j]=4*3*i*(j+4*1)-4*2*i*j;
}
}
}
//////////////////////////////////
for(int m=0;m<16;m++)//stage 4
{
for(int i=0;i<4;i++)
{
for(int j=0;j<1;j++)
{
tab5[0*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j]=16*0*i*(j+1*0)+16*1*i*j;
tab5[1*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j]=16*1*i*(j+1*1)+16*0*i*j;
tab5[2*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j]=16*2*i*(j+1*1)-16*1*i*j;
tab5[3*N/(4*4*4*4)+N/(4*4*4)*i+N/(4*4)*m+j]=16*3*i*(j+1*1)-16*2*i*j;
}
}
}
/////////////////////////////////
poniedziałek, 10 kwietnia 2017
my interpretation of FFT 16*radix-4 for N=16 algorithm c++ source code
////https://www.beechwood.eu/fft-implementation-r2-dit-r4-dif-r8-dif/
//my interpretation of FFT 16*radix-4 for N=16 algorithm c++ source code it works witch
// FFT=+/-cos(w+fi)-isin(w+fi) and maybe witch other functions that are mirror inverse
//author marcin matysek (r)ewertyn.PL
#include <iostream>
#include "conio.h"
#include <stdlib.h>
#include <math.h>
#include <complex>
#include <fstream>
using namespace std;
void fun_fourier_transform_DFT_method5_full_complex(int N,std::complex<double> tab[]);
void fun_fourier_transform_FFT_radix_4_N_4(int N,std::complex<double> tab[]);
void fun_inverse_bits_radix_4(int N,std::complex<double> tab[]);
int b1,b2,b3;
double fi=-0.41;
int main()
{
std::complex<double>tab2[16]={};
std::complex<double>tab3[16]={};
std::fstream plik;
plik.open("test.txt", std::ios::in | std::ios::out);
/*
if( plik.good() == false )
{
cout<<"create file : test.txt"<<endl;
system("pause");
}
*/
int N=16;
for(int i=0;i<N;i++)
{
tab2[i].real()=i*1.2+1;
tab2[i].imag()=i*3.2+11;
tab3[i].real()=i*1.2+1;
tab3[i].imag()=i*3.2+11;
}
cout<<endl;
cout<<"signal g(x)"<<endl;
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab2[j].real()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab2[j].imag()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
cout<<"signal g(x)"<<endl;
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab3[j].real()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab3[j].imag()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
for(int i1=0;i1<2;i1++)
{
if(i1==0){b1=0;}
if(i1==1){b1=1;}
for(int i2=0;i2<2;i2++)
{
if(i2==0){b2=0;}
if(i2==1){b2=1;}
for(int i3=0;i3<2;i3++)
{
if(i3==0){b3=0;}
if(i3==1){b3=1;}
for(int i=0;i<N;i++)
{
tab2[i].real()=i*1.2+1;
tab2[i].imag()=i*3.2+11;
tab3[i].real()=i*1.2+1;
tab3[i].imag()=i*3.2+11;
}
fun_fourier_transform_DFT_method5_full_complex(N,tab2);
fun_fourier_transform_FFT_radix_4_N_4(N,tab3);
cout<<endl;
cout<<endl;
cout<<endl;
cout<<endl;
cout<<"frequency Hz DFT:"<<endl;
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab2[j].real()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab2[j].imag()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
cout<<endl;
cout<<"frequency Hz radix4:"<<endl;
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab3[j].real()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
for(int j=0;j<N;j++)
{
cout.precision(4);
cout<<round(tab3[j].imag()*1000)/1000<<" ";
}
cout<<endl;
cout<<endl;
cout<<endl;
if((((fabs(tab3[0].real())-fabs(tab2[0].real())>=-0.03)&&(fabs(tab3[0].real())-fabs(tab2[0].real())<=0.03))&&
((fabs(tab3[1].real())-fabs(tab2[1].real())>=-0.03)&&(fabs(tab3[1].real())-fabs(tab2[1].real())<=0.03))&&
((fabs(tab3[2].real())-fabs(tab2[2].real())>=-0.03)&&(fabs(tab3[2].real())-fabs(tab2[2].real())<=0.03))&&
((fabs(tab3[3].real())-fabs(tab2[3].real())>=-0.03)&&(fabs(tab3[3].real())-fabs(tab2[3].real())<=0.03)))
)
{
cout<<"DFT==FFT =>";
cout<<endl;
for(int j=0;j<N;j++)
{
if(((tab3[j].real()-tab2[j].real()>=-0.03)&&(tab3[j].real()-tab2[j].real()<=0.03)))
{
cout.precision(4);
cout<<round(tab2[j].real()*1000)/1000<<" ";//system("pause");
}
else {
cout<<-1<<" . ";
}
}
cout<<endl<<endl;
cout<<", b1="<<b1<<" b2="<<b2<<" b3="<<b3<<endl<<endl;system("pause");
// plik<<a1<<" "<<a2<<" "<<a3<<" "<<a4<<" "<<a5<<" "<<a11<<" , "<<a12<<" "<<a13<<" "<<a14<<" "<<a15<<" "<<a16<<" "<<endl;
}
}}}
//cout<<"end:"<<endl;
cout<<endl;
cout<<endl;
//plik.close();
system("pause");
return 0;
}
///////////////
void fun_fourier_transform_DFT_method5_full_complex(int N,std::complex<double> tab[])
{
const double pi=3.141592653589793238462;
std::complex<double> tab2[16]={}; // tab2[]==N
std::complex<double> w[1]={{1,1}};
double zmienna1=2*pi/(float)N;
double fi2=fi;
for (int i=0;i<N;i++)
{
for(int j=0;j<N;j++)
{
//complex number method:
w[0].real()=-cos(i*j*zmienna1+fi2);
w[0].imag()=(-sin(i*j*zmienna1+fi2));
tab2[i]=tab2[i]+tab[j]*w[0];
}
}
for(int j=0;j<N;j++)
{
tab[j].real() =tab2[j].real()*2/N;
tab[j].imag() =tab2[j].imag()*2/N;
}
}
//////////////////
void fun_inverse_bits_radix_4(int N,std::complex<double> tab[])
{
}
///////////////////
void fun_fourier_transform_FFT_radix_4_N_4(int N,std::complex<double> tab[])
{
const double pi=3.141592653589793238462;
std::complex<double> tab2[64]={}; // tab2[]==N
std::complex<double> w0[1]={{1,0}};
std::complex<double> w1[1]={{1,0}};
std::complex<double> w2[1]={{1,0}};
std::complex<double> w3[1]={{1,0}};
std::complex<double> a0,a1,a2,a3,a4,a6,a9;
double zm=2*pi/4;
double wbm=2*pi/N;
double fi1;
int nr1=1;
int nr2=1;
int nr3=1;
if(b1==0){nr1=-1;}
else if(b1==1){nr1=1;}
else{}
if(b2==0){nr2=-1;}
else if(b2==1){nr2=1;}
else{}
if(b3==0){nr3=-1;}
else if(b3==1){nr3=1;}
else{}
//cout<<"b1="<<b1<<endl<<endl;
// nr1=1;
// nr2=-1;
// nr3=1;
fi1=fi;
a0.real()=nr1*cos(0*zm+fi1);
a0.imag()=-sin(0*zm+fi1);
a1.real()=nr1*cos(1*zm+fi1);
a1.imag()=-sin(1*zm+fi1);
a2.real()=nr1*cos(2*zm+fi1);
a2.imag()=-sin(2*zm+fi1);
a3.real()=nr1*cos(3*zm+fi1);
a3.imag()=-sin(3*zm+fi1);
a4.real()=nr1*cos(4*zm+fi1);
a4.imag()=-sin(4*zm+fi1);
a6.real()=nr1*cos(6*zm+fi1);
a6.imag()=-sin(6*zm+fi1);
a9.real()=nr1*cos(9*zm+fi1);
a9.imag()=-sin(9*zm+fi1);
//cout.precision(3);
//cout<<" ["<<round(a0.real()*1000)/1000<<" "<<round(a0.imag()*1000)/1000<<"i] ["<<round(a0.real()*1000)/1000<<" "<<round(a0.imag()*1000)/1000<<"i] ["<<round(a0.real()*1000)/1000<<" "<<round(a0.imag()*1000)/1000<<"i] ["<<round(a0.real()*1000)/1000<<" "<<round(a0.imag()*1000)/1000<<"i] "<<endl;
//// cout<<" ["<<round(a0.real()*1000)/1000<<" "<<round(a0.imag()*1000)/1000<<"i] ["<<round(a1.real()*1000)/1000<<" "<<round(a1.imag()*1000)/1000<<"i] ["<<round(a2.real()*1000)/1000<<" "<<round(a2.imag()*1000)/1000<<"i] ["<<round(a3.real()*1000)/1000<<" "<<round(a3.imag()*1000)/1000<<"i] "<<endl;
// cout<<" ["<<round(a0.real()*1000)/1000<<" "<<round(a0.imag()*1000)/1000<<"i] ["<<round(a2.real()*1000)/1000<<" "<<round(a2.imag()*1000)/1000<<"i] ["<<round(a4.real()*1000)/1000<<" "<<round(a4.imag()*1000)/1000<<"i] ["<<round(a6.real()*1000)/1000<<" "<<round(a6.imag()*1000)/1000<<"i] "<<endl;
//cout<<" ["<<round(a0.real()*1000)/1000<<" "<<round(a0.imag()*1000)/1000<<"i] ["<<round(a3.real())<<" "<<round(a3.imag())<<"i] ["<<round(a6.real())<<" "<<round(a6.imag())<<"i] ["<<round(a9.real())<<" "<<round(a9.imag())<<"i] "<<endl;
//system("pause");
//radix-4
w0[0].real()=nr3*cos(0+fi1);
w0[0].imag()=-sin(0+fi1);
for(int k=0;k<4;k++)
{
for(int n=0;n<4;n++)
{
w2[0].real()=nr2*cos(n*k*2*pi/(N/4)+fi1);
w2[0].imag()=-sin(n*k*2*pi/(N/4)+fi1);
tab2[4*k+0]=tab2[4*k+0]+(-a0*tab[n]-a0*tab[n+4]-a0*tab[n+8]-a0*tab[n+12])*w0[0]*w2[0];
w1[0].real()=nr3*cos(n*wbm+fi1);
w1[0].imag()=-sin(n*wbm+fi1);
tab2[4*k+1]=tab2[4*k+1]+(-a0*tab[n]-a1*tab[n+4]-a2*tab[n+8]-a3*tab[n+12])*w1[0]*w2[0];
w1[0].real()=nr3*cos(2*n*wbm+fi1);
w1[0].imag()=-sin(2*n*wbm+fi1);
tab2[4*k+2]=tab2[4*k+2]+(-a0*tab[n]-a2*tab[n+4]-a4*tab[n+8]-a6*tab[n+12])*w1[0]*w2[0];
w1[0].real()=nr3*cos(3*n*wbm+fi1);
w1[0].imag()=-sin(3*n*wbm+fi1);
tab2[4*k+3]=tab2[4*k+3]+(-a0*tab[n]-a3*tab[n+4]-a6*tab[n+8]-a9*tab[n+12])*w1[0]*w2[0];
}
}
/////////////////////////////
//inverse
std::complex<double> tmp;
tmp=tab2[4];
tab2[4]=tab2[12];
tab2[12]=tmp;
tmp=tab2[4+1];
tab2[4+1]=tab2[12+1];
tab2[12+1]=tmp;
tmp=tab2[4+2];
tab2[4+2]=tab2[12+2];
tab2[12+2]=tmp;
tmp=tab2[4+3];
tab2[4+3]=tab2[12+3];
tab2[12+3]=tmp;
for(int j=0;j<N;j++)
{
tab[j].real() =tab2[j].real()*2/N;
tab[j].imag() =tab2[j].imag()*2/N;
}
}
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