ViennaCL - The Vienna Computing Library  1.5.2
viennacl/linalg/toeplitz_matrix_operations.hpp
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00001 #ifndef VIENNACL_LINALG_TOEPLITZ_MATRIX_OPERATIONS_HPP_
00002 #define VIENNACL_LINALG_TOEPLITZ_MATRIX_OPERATIONS_HPP_
00003 
00004 /* =========================================================================
00005    Copyright (c) 2010-2014, Institute for Microelectronics,
00006                             Institute for Analysis and Scientific Computing,
00007                             TU Wien.
00008    Portions of this software are copyright by UChicago Argonne, LLC.
00009 
00010                             -----------------
00011                   ViennaCL - The Vienna Computing Library
00012                             -----------------
00013 
00014    Project Head:    Karl Rupp                   rupp@iue.tuwien.ac.at
00015 
00016    (A list of authors and contributors can be found in the PDF manual)
00017 
00018    License:         MIT (X11), see file LICENSE in the base directory
00019 ============================================================================= */
00020 
00025 #include "viennacl/forwards.h"
00026 #include "viennacl/ocl/backend.hpp"
00027 #include "viennacl/scalar.hpp"
00028 #include "viennacl/vector.hpp"
00029 #include "viennacl/tools/tools.hpp"
00030 #include "viennacl/fft.hpp"
00031 
00032 namespace viennacl
00033 {
00034   namespace linalg
00035   {
00036 
00037 
00038     // A * x
00039 
00048     template<class SCALARTYPE, unsigned int ALIGNMENT>
00049     void prod_impl(const viennacl::toeplitz_matrix<SCALARTYPE, ALIGNMENT> & mat,
00050                    const viennacl::vector_base<SCALARTYPE> & vec,
00051                          viennacl::vector_base<SCALARTYPE> & result)
00052     {
00053       assert(mat.size1() == result.size());
00054       assert(mat.size2() == vec.size());
00055 
00056       viennacl::vector<SCALARTYPE> tmp(vec.size() * 4); tmp.clear();
00057       viennacl::vector<SCALARTYPE> tmp2(vec.size() * 4);
00058 
00059       viennacl::vector<SCALARTYPE> tep(mat.elements().size() * 2);
00060       viennacl::detail::fft::real_to_complex(mat.elements(), tep, mat.elements().size());
00061 
00062 
00063 
00064       copy(vec, tmp);
00065       viennacl::detail::fft::real_to_complex(tmp, tmp2, vec.size() * 2);
00066       viennacl::linalg::convolve(tep, tmp2, tmp);
00067       viennacl::detail::fft::complex_to_real(tmp, tmp2, vec.size() * 2);
00068       copy(tmp2.begin(), tmp2.begin() + static_cast<vcl_ptrdiff_t>(vec.size()), result.begin());
00069     }
00070 
00071   } //namespace linalg
00072 
00073 
00074 
00075 } //namespace viennacl
00076 
00077 
00078 #endif