changed name from simple_fft_traits to ei_kissfft_impl

1 files changed, 95 insertions, 0 deletions

diff --git a/unsupported/Eigen/FFT b/unsupported/Eigen/FFT
new file mode 100644
index 000000000..3d852f5a2
--- /dev/null
+++ b/unsupported/Eigen/FFT
@@ -0,0 +1,95 @@
+// This file is part of Eigen, a lightweight C++ template library
+// for linear algebra. Eigen itself is part of the KDE project.
+//
+// Copyright (C) 2009 Mark Borgerding mark a borgerding net
+//
+// Eigen is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Lesser General Public
+// License as published by the Free Software Foundation; either
+// version 3 of the License, or (at your option) any later version.
+//
+// Alternatively, you can redistribute it and/or
+// modify it under the terms of the GNU General Public License as
+// published by the Free Software Foundation; either version 2 of
+// the License, or (at your option) any later version.
+//
+// Eigen is distributed in the hope that it will be useful, but WITHOUT ANY
+// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+// FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License or the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License and a copy of the GNU General Public License along with
+// Eigen. If not, see <http://www.gnu.org/licenses/>.
+
+#ifndef EIGEN_FFT_H
+#define EIGEN_FFT_H
+
+// ei_kissfft_impl:  small, free, reasonably efficient default, derived from kissfft
+#include "src/FFT/ei_kissfft_impl.h"
+#define DEFAULT_FFT_IMPL ei_kissfft_impl
+
+// FFTW: faster, GPL-not LGPL, bigger code size
+#ifdef FFTW_PATIENT  // definition of FFTW_PATIENT indicates the caller has included fftw3.h, we can use FFTW routines
+// TODO 
+// #include "src/FFT/ei_fftw_impl.h"
+// #define DEFAULT_FFT_IMPL ei_fftw_impl
+#endif
+
+// intel Math Kernel Library: fastest, commerical
+#ifdef _MKL_DFTI_H_ // mkl_dfti.h has been included, we can use MKL FFT routines
+// TODO 
+// #include "src/FFT/ei_imkl_impl.h"
+// #define DEFAULT_FFT_IMPL ei_imkl_impl
+#endif
+
+namespace Eigen {
+
+template <typename _Scalar,
+         typename _Traits=DEFAULT_FFT_IMPL<_Scalar> 
+         >
+class FFT
+{
+  public:
+    typedef _Traits traits_type;
+    typedef typename traits_type::Scalar Scalar;
+    typedef typename traits_type::Complex Complex;
+
+    FFT(const traits_type & traits=traits_type() ) :m_traits(traits) { }
+
+    template <typename _Input>
+    void fwd( Complex * dst, const _Input * src, int nfft)
+    {
+        m_traits.fwd(dst,src,nfft);
+    }
+
+    template <typename _Input>
+    void fwd( std::vector<Complex> & dst, const std::vector<_Input> & src) 
+    {
+        dst.resize( src.size() );
+        fwd( &dst[0],&src[0],src.size() );
+    }
+
+    template <typename _Output>
+    void inv( _Output * dst, const Complex * src, int nfft)
+    {
+        m_traits.inv( dst,src,nfft );
+    }
+
+    template <typename _Output>
+    void inv( std::vector<_Output> & dst, const std::vector<Complex> & src) 
+    {
+        dst.resize( src.size() );
+        inv( &dst[0],&src[0],src.size() );
+    }
+
+    // TODO: multi-dimensional FFTs
+    // TODO: handle Eigen MatrixBase
+
+    traits_type & traits() {return m_traits;}
+  private:
+    traits_type m_traits;
+};
+#undef DEFAULT_FFT_IMPL
+}
+#endif