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-rw-r--r--third_party/eigen3/unsupported/Eigen/src/FFT/ei_kissfft_impl.h420
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diff --git a/third_party/eigen3/unsupported/Eigen/src/FFT/ei_kissfft_impl.h b/third_party/eigen3/unsupported/Eigen/src/FFT/ei_kissfft_impl.h
deleted file mode 100644
index be51b4e6fe..0000000000
--- a/third_party/eigen3/unsupported/Eigen/src/FFT/ei_kissfft_impl.h
+++ /dev/null
@@ -1,420 +0,0 @@
-// This file is part of Eigen, a lightweight C++ template library
-// for linear algebra.
-//
-// Copyright (C) 2009 Mark Borgerding mark a borgerding net
-//
-// This Source Code Form is subject to the terms of the Mozilla
-// Public License v. 2.0. If a copy of the MPL was not distributed
-// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
-
-namespace Eigen {
-
-namespace internal {
-
- // This FFT implementation was derived from kissfft http:sourceforge.net/projects/kissfft
- // Copyright 2003-2009 Mark Borgerding
-
-template <typename _Scalar>
-struct kiss_cpx_fft
-{
- typedef _Scalar Scalar;
- typedef std::complex<Scalar> Complex;
- std::vector<Complex> m_twiddles;
- std::vector<int> m_stageRadix;
- std::vector<int> m_stageRemainder;
- std::vector<Complex> m_scratchBuf;
- bool m_inverse;
-
- inline
- void make_twiddles(int nfft,bool inverse)
- {
- using std::acos;
- m_inverse = inverse;
- m_twiddles.resize(nfft);
- Scalar phinc = (inverse?2:-2)* acos( (Scalar) -1) / nfft;
- for (int i=0;i<nfft;++i)
- m_twiddles[i] = exp( Complex(0,i*phinc) );
- }
-
- void factorize(int nfft)
- {
- //start factoring out 4's, then 2's, then 3,5,7,9,...
- int n= nfft;
- int p=4;
- do {
- while (n % p) {
- switch (p) {
- case 4: p = 2; break;
- case 2: p = 3; break;
- default: p += 2; break;
- }
- if (p*p>n)
- p=n;// impossible to have a factor > sqrt(n)
- }
- n /= p;
- m_stageRadix.push_back(p);
- m_stageRemainder.push_back(n);
- if ( p > 5 )
- m_scratchBuf.resize(p); // scratchbuf will be needed in bfly_generic
- }while(n>1);
- }
-
- template <typename _Src>
- inline
- void work( int stage,Complex * xout, const _Src * xin, size_t fstride,size_t in_stride)
- {
- int p = m_stageRadix[stage];
- int m = m_stageRemainder[stage];
- Complex * Fout_beg = xout;
- Complex * Fout_end = xout + p*m;
-
- if (m>1) {
- do{
- // recursive call:
- // DFT of size m*p performed by doing
- // p instances of smaller DFTs of size m,
- // each one takes a decimated version of the input
- work(stage+1, xout , xin, fstride*p,in_stride);
- xin += fstride*in_stride;
- }while( (xout += m) != Fout_end );
- }else{
- do{
- *xout = *xin;
- xin += fstride*in_stride;
- }while(++xout != Fout_end );
- }
- xout=Fout_beg;
-
- // recombine the p smaller DFTs
- switch (p) {
- case 2: bfly2(xout,fstride,m); break;
- case 3: bfly3(xout,fstride,m); break;
- case 4: bfly4(xout,fstride,m); break;
- case 5: bfly5(xout,fstride,m); break;
- default: bfly_generic(xout,fstride,m,p); break;
- }
- }
-
- inline
- void bfly2( Complex * Fout, const size_t fstride, int m)
- {
- for (int k=0;k<m;++k) {
- Complex t = Fout[m+k] * m_twiddles[k*fstride];
- Fout[m+k] = Fout[k] - t;
- Fout[k] += t;
- }
- }
-
- inline
- void bfly4( Complex * Fout, const size_t fstride, const size_t m)
- {
- Complex scratch[6];
- int negative_if_inverse = m_inverse * -2 +1;
- for (size_t k=0;k<m;++k) {
- scratch[0] = Fout[k+m] * m_twiddles[k*fstride];
- scratch[1] = Fout[k+2*m] * m_twiddles[k*fstride*2];
- scratch[2] = Fout[k+3*m] * m_twiddles[k*fstride*3];
- scratch[5] = Fout[k] - scratch[1];
-
- Fout[k] += scratch[1];
- scratch[3] = scratch[0] + scratch[2];
- scratch[4] = scratch[0] - scratch[2];
- scratch[4] = Complex( scratch[4].imag()*negative_if_inverse , -scratch[4].real()* negative_if_inverse );
-
- Fout[k+2*m] = Fout[k] - scratch[3];
- Fout[k] += scratch[3];
- Fout[k+m] = scratch[5] + scratch[4];
- Fout[k+3*m] = scratch[5] - scratch[4];
- }
- }
-
- inline
- void bfly3( Complex * Fout, const size_t fstride, const size_t m)
- {
- size_t k=m;
- const size_t m2 = 2*m;
- Complex *tw1,*tw2;
- Complex scratch[5];
- Complex epi3;
- epi3 = m_twiddles[fstride*m];
-
- tw1=tw2=&m_twiddles[0];
-
- do{
- scratch[1]=Fout[m] * *tw1;
- scratch[2]=Fout[m2] * *tw2;
-
- scratch[3]=scratch[1]+scratch[2];
- scratch[0]=scratch[1]-scratch[2];
- tw1 += fstride;
- tw2 += fstride*2;
- Fout[m] = Complex( Fout->real() - Scalar(.5)*scratch[3].real() , Fout->imag() - Scalar(.5)*scratch[3].imag() );
- scratch[0] *= epi3.imag();
- *Fout += scratch[3];
- Fout[m2] = Complex( Fout[m].real() + scratch[0].imag() , Fout[m].imag() - scratch[0].real() );
- Fout[m] += Complex( -scratch[0].imag(),scratch[0].real() );
- ++Fout;
- }while(--k);
- }
-
- inline
- void bfly5( Complex * Fout, const size_t fstride, const size_t m)
- {
- Complex *Fout0,*Fout1,*Fout2,*Fout3,*Fout4;
- size_t u;
- Complex scratch[13];
- Complex * twiddles = &m_twiddles[0];
- Complex *tw;
- Complex ya,yb;
- ya = twiddles[fstride*m];
- yb = twiddles[fstride*2*m];
-
- Fout0=Fout;
- Fout1=Fout0+m;
- Fout2=Fout0+2*m;
- Fout3=Fout0+3*m;
- Fout4=Fout0+4*m;
-
- tw=twiddles;
- for ( u=0; u<m; ++u ) {
- scratch[0] = *Fout0;
-
- scratch[1] = *Fout1 * tw[u*fstride];
- scratch[2] = *Fout2 * tw[2*u*fstride];
- scratch[3] = *Fout3 * tw[3*u*fstride];
- scratch[4] = *Fout4 * tw[4*u*fstride];
-
- scratch[7] = scratch[1] + scratch[4];
- scratch[10] = scratch[1] - scratch[4];
- scratch[8] = scratch[2] + scratch[3];
- scratch[9] = scratch[2] - scratch[3];
-
- *Fout0 += scratch[7];
- *Fout0 += scratch[8];
-
- scratch[5] = scratch[0] + Complex(
- (scratch[7].real()*ya.real() ) + (scratch[8].real() *yb.real() ),
- (scratch[7].imag()*ya.real()) + (scratch[8].imag()*yb.real())
- );
-
- scratch[6] = Complex(
- (scratch[10].imag()*ya.imag()) + (scratch[9].imag()*yb.imag()),
- -(scratch[10].real()*ya.imag()) - (scratch[9].real()*yb.imag())
- );
-
- *Fout1 = scratch[5] - scratch[6];
- *Fout4 = scratch[5] + scratch[6];
-
- scratch[11] = scratch[0] +
- Complex(
- (scratch[7].real()*yb.real()) + (scratch[8].real()*ya.real()),
- (scratch[7].imag()*yb.real()) + (scratch[8].imag()*ya.real())
- );
-
- scratch[12] = Complex(
- -(scratch[10].imag()*yb.imag()) + (scratch[9].imag()*ya.imag()),
- (scratch[10].real()*yb.imag()) - (scratch[9].real()*ya.imag())
- );
-
- *Fout2=scratch[11]+scratch[12];
- *Fout3=scratch[11]-scratch[12];
-
- ++Fout0;++Fout1;++Fout2;++Fout3;++Fout4;
- }
- }
-
- /* perform the butterfly for one stage of a mixed radix FFT */
- inline
- void bfly_generic(
- Complex * Fout,
- const size_t fstride,
- int m,
- int p
- )
- {
- int u,k,q1,q;
- Complex * twiddles = &m_twiddles[0];
- Complex t;
- int Norig = static_cast<int>(m_twiddles.size());
- Complex * scratchbuf = &m_scratchBuf[0];
-
- for ( u=0; u<m; ++u ) {
- k=u;
- for ( q1=0 ; q1<p ; ++q1 ) {
- scratchbuf[q1] = Fout[ k ];
- k += m;
- }
-
- k=u;
- for ( q1=0 ; q1<p ; ++q1 ) {
- int twidx=0;
- Fout[ k ] = scratchbuf[0];
- for (q=1;q<p;++q ) {
- twidx += static_cast<int>(fstride) * k;
- if (twidx>=Norig) twidx-=Norig;
- t=scratchbuf[q] * twiddles[twidx];
- Fout[ k ] += t;
- }
- k += m;
- }
- }
- }
-};
-
-template <typename _Scalar>
-struct kissfft_impl
-{
- typedef _Scalar Scalar;
- typedef std::complex<Scalar> Complex;
-
- void clear()
- {
- m_plans.clear();
- m_realTwiddles.clear();
- }
-
- inline
- void fwd( Complex * dst,const Complex *src,int nfft)
- {
- get_plan(nfft,false).work(0, dst, src, 1,1);
- }
-
- inline
- void fwd2( Complex * dst,const Complex *src,int n0,int n1)
- {
- EIGEN_UNUSED_VARIABLE(dst);
- EIGEN_UNUSED_VARIABLE(src);
- EIGEN_UNUSED_VARIABLE(n0);
- EIGEN_UNUSED_VARIABLE(n1);
- }
-
- inline
- void inv2( Complex * dst,const Complex *src,int n0,int n1)
- {
- EIGEN_UNUSED_VARIABLE(dst);
- EIGEN_UNUSED_VARIABLE(src);
- EIGEN_UNUSED_VARIABLE(n0);
- EIGEN_UNUSED_VARIABLE(n1);
- }
-
- // real-to-complex forward FFT
- // perform two FFTs of src even and src odd
- // then twiddle to recombine them into the half-spectrum format
- // then fill in the conjugate symmetric half
- inline
- void fwd( Complex * dst,const Scalar * src,int nfft)
- {
- if ( nfft&3 ) {
- // use generic mode for odd
- m_tmpBuf1.resize(nfft);
- get_plan(nfft,false).work(0, &m_tmpBuf1[0], src, 1,1);
- std::copy(m_tmpBuf1.begin(),m_tmpBuf1.begin()+(nfft>>1)+1,dst );
- }else{
- int ncfft = nfft>>1;
- int ncfft2 = nfft>>2;
- Complex * rtw = real_twiddles(ncfft2);
-
- // use optimized mode for even real
- fwd( dst, reinterpret_cast<const Complex*> (src), ncfft);
- Complex dc = dst[0].real() + dst[0].imag();
- Complex nyquist = dst[0].real() - dst[0].imag();
- int k;
- for ( k=1;k <= ncfft2 ; ++k ) {
- Complex fpk = dst[k];
- Complex fpnk = conj(dst[ncfft-k]);
- Complex f1k = fpk + fpnk;
- Complex f2k = fpk - fpnk;
- Complex tw= f2k * rtw[k-1];
- dst[k] = (f1k + tw) * Scalar(.5);
- dst[ncfft-k] = conj(f1k -tw)*Scalar(.5);
- }
- dst[0] = dc;
- dst[ncfft] = nyquist;
- }
- }
-
- // inverse complex-to-complex
- inline
- void inv(Complex * dst,const Complex *src,int nfft)
- {
- get_plan(nfft,true).work(0, dst, src, 1,1);
- }
-
- // half-complex to scalar
- inline
- void inv( Scalar * dst,const Complex * src,int nfft)
- {
- if (nfft&3) {
- m_tmpBuf1.resize(nfft);
- m_tmpBuf2.resize(nfft);
- std::copy(src,src+(nfft>>1)+1,m_tmpBuf1.begin() );
- for (int k=1;k<(nfft>>1)+1;++k)
- m_tmpBuf1[nfft-k] = conj(m_tmpBuf1[k]);
- inv(&m_tmpBuf2[0],&m_tmpBuf1[0],nfft);
- for (int k=0;k<nfft;++k)
- dst[k] = m_tmpBuf2[k].real();
- }else{
- // optimized version for multiple of 4
- int ncfft = nfft>>1;
- int ncfft2 = nfft>>2;
- Complex * rtw = real_twiddles(ncfft2);
- m_tmpBuf1.resize(ncfft);
- m_tmpBuf1[0] = Complex( src[0].real() + src[ncfft].real(), src[0].real() - src[ncfft].real() );
- for (int k = 1; k <= ncfft / 2; ++k) {
- Complex fk = src[k];
- Complex fnkc = conj(src[ncfft-k]);
- Complex fek = fk + fnkc;
- Complex tmp = fk - fnkc;
- Complex fok = tmp * conj(rtw[k-1]);
- m_tmpBuf1[k] = fek + fok;
- m_tmpBuf1[ncfft-k] = conj(fek - fok);
- }
- get_plan(ncfft,true).work(0, reinterpret_cast<Complex*>(dst), &m_tmpBuf1[0], 1,1);
- }
- }
-
- protected:
- typedef kiss_cpx_fft<Scalar> PlanData;
- typedef std::map<int,PlanData> PlanMap;
-
- PlanMap m_plans;
- std::map<int, std::vector<Complex> > m_realTwiddles;
- std::vector<Complex> m_tmpBuf1;
- std::vector<Complex> m_tmpBuf2;
-
- inline
- int PlanKey(int nfft, bool isinverse) const { return (nfft<<1) | int(isinverse); }
-
- inline
- PlanData & get_plan(int nfft, bool inverse)
- {
- // TODO look for PlanKey(nfft, ! inverse) and conjugate the twiddles
- PlanData & pd = m_plans[ PlanKey(nfft,inverse) ];
- if ( pd.m_twiddles.size() == 0 ) {
- pd.make_twiddles(nfft,inverse);
- pd.factorize(nfft);
- }
- return pd;
- }
-
- inline
- Complex * real_twiddles(int ncfft2)
- {
- using std::acos;
- std::vector<Complex> & twidref = m_realTwiddles[ncfft2];// creates new if not there
- if ( (int)twidref.size() != ncfft2 ) {
- twidref.resize(ncfft2);
- int ncfft= ncfft2<<1;
- Scalar pi = acos( Scalar(-1) );
- for (int k=1;k<=ncfft2;++k)
- twidref[k-1] = exp( Complex(0,-pi * (Scalar(k) / ncfft + Scalar(.5)) ) );
- }
- return &twidref[0];
- }
-};
-
-} // end namespace internal
-
-} // end namespace Eigen
-
-/* vim: set filetype=cpp et sw=2 ts=2 ai: */
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