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Removed the needless use of a traits class.

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This commit is contained in:
Ralph Tandetzky 2016-04-21 13:20:29 +02:00
parent b10fb43644
commit 0395af753e
1 changed files with 27 additions and 53 deletions
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64
kissfft.hh
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@ -3,35 +3,30 @@
#include <complex> #include <complex>
#include <vector> #include <vector>
namespace kissfft_utils {
template <typename T_scalar> template <typename T_Scalar,
struct traits typename T_Complex=std::complex<T_Scalar>
>
class kissfft
{ {
typedef T_scalar scalar_type; public:
typedef std::complex<scalar_type> cpx_type; typedef T_Scalar scalar_type;
static void fill_twiddles( cpx_type * dst, typedef T_Complex cpx_type;
std::size_t nfft,
bool inverse )
{
const T_scalar phinc = (inverse?2:-2)* acos( (T_scalar) -1) / nfft;
for (std::size_t i=0;i<nfft;++i)
dst[i] = std::exp( cpx_type(0,i*phinc) );
}
static void prepare( kissfft( std::size_t nfft,
std::vector< cpx_type > & _twiddles, bool inverse )
std::size_t nfft, :_nfft(nfft)
bool inverse, ,_inverse(inverse)
std::vector<std::size_t> & stageRadix,
std::vector<std::size_t> & stageRemainder )
{ {
_twiddles.resize(nfft); // fill twiddle factors
fill_twiddles( &_twiddles[0],nfft,inverse); _twiddles.resize(_nfft);
const scalar_type phinc = (_inverse?2:-2)* acos( (scalar_type) -1) / _nfft;
for (std::size_t i=0;i<_nfft;++i)
_twiddles[i] = std::exp( cpx_type(0,i*phinc) );
//factorize //factorize
//start factoring out 4's, then 2's, then 3,5,7,9,... //start factoring out 4's, then 2's, then 3,5,7,9,...
std::size_t n= nfft; std::size_t n= _nfft;
std::size_t p=4; std::size_t p=4;
do { do {
while (n % p) { while (n % p) {
@ -44,31 +39,10 @@ struct traits
p = n;// no more factors p = n;// no more factors
} }
n /= p; n /= p;
stageRadix.push_back(p); _stageRadix.push_back(p);
stageRemainder.push_back(n); _stageRemainder.push_back(n);
}while(n>1); }while(n>1);
} }
};
}
template <typename T_Scalar,
typename T_traits=kissfft_utils::traits<T_Scalar>
>
class kissfft
{
public:
typedef T_traits traits_type;
typedef typename traits_type::scalar_type scalar_type;
typedef typename traits_type::cpx_type cpx_type;
kissfft( std::size_t nfft,
bool inverse )
:_nfft(nfft)
,_inverse(inverse)
{
T_traits::prepare(_twiddles, _nfft,_inverse ,_stageRadix, _stageRemainder);
}
void transform( const cpx_type * src, void transform( const cpx_type * src,
cpx_type * dst ) const cpx_type * dst ) const