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first addition of kissfft.hh the C++ template fft engine

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This commit is contained in:
Mark Borgerding
2009-05-17 23:57:26 +00:00
parent 9dbaf860f2
commit 2b5477d54c
3 changed files with 407 additions and 0 deletions
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test/testcpp.cc Normal file
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#include "kissfft.hh"
#include <iostream>
#include <cstdlib>
#include <typeinfo>
#include <sys/time.h>
static inline
double curtime(void)
{
struct timeval tv;
gettimeofday(&tv, NULL);
return (double)tv.tv_sec + (double)tv.tv_usec*.000001;
}
using namespace std;
template <class T>
void dotest(int nfft)
{
typedef kissfft<T> FFT;
typedef std::complex<T> cpx_type;
cout << typeid(T).name() << ":nfft=" << nfft <<endl;
FFT fft(nfft,false);
vector<cpx_type> inbuf(nfft);
vector<cpx_type> outbuf(nfft);
#if 0
for (int k=0;k<nfft;++k)
inbuf[k]= cpx_type(
cosl(2*k* M_PIl / nfft ),
sinl(2*k* M_PIl / nfft ) );
#else
for (int k=0;k<nfft;++k)
inbuf[k]= cpx_type(
(T)(rand()/(double)RAND_MAX - .5),
(T)(rand()/(double)RAND_MAX - .5) );
#endif
fft.transform( &inbuf[0] , &outbuf[0] );
long double totalpower=0;
long double difpower=0;
for (int k0=0;k0<nfft;++k0) {
complex<long double> acc = 0;
long double phinc = 2*k0* M_PIl / nfft;
for (int k1=0;k1<nfft;++k1) {
complex<long double> x(inbuf[k1].real(),inbuf[k1].imag());
acc += x * exp( complex<long double>(0,-k1*phinc) );
}
totalpower += norm(acc);
complex<long double> x(outbuf[k0].real(),outbuf[k0].imag());
complex<long double> dif = acc - x;
difpower += norm(dif);
}
cout << "RMSE:" << sqrt(difpower/totalpower) << "\t";
double t0 = curtime();
int nits=20e6/nfft;
for (int k=0;k<nits;++k) {
fft.transform( &inbuf[0] , &outbuf[0] );
}
double t1 = curtime();
cout << "MSPS:" << ( (nits*nfft)*1e-6/ (t1-t0) ) << endl;
}
int main(int argc,char ** argv)
{
dotest<float>(32);
dotest<double>(32);
dotest<long double>(32);
dotest<float>(1024); dotest<double>(1024); dotest<long double>(1024);
dotest<float>(1800); dotest<double>(1800); dotest<long double>(1800);
return 0;
}