ViennaCL - The Vienna Computing Library  1.5.0
viennacl/linalg/circulant_matrix_operations.hpp
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00001 #ifndef VIENNACL_LINALG_CIRCULANT_MATRIX_OPERATIONS_HPP_
00002 #define VIENNACL_LINALG_CIRCULANT_MATRIX_OPERATIONS_HPP_
00003 
00004 /* =========================================================================
00005    Copyright (c) 2010-2013, 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 //#include "viennacl/linalg/kernels/coordinate_matrix_kernels.h"
00032 
00033 namespace viennacl
00034 {
00035   namespace linalg
00036   {
00037 
00038     // A * x
00039 
00048       template<class SCALARTYPE, unsigned int ALIGNMENT>
00049       void prod_impl(const viennacl::circulant_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         //result.clear();
00056 
00057         //std::cout << "prod(circulant_matrix" << ALIGNMENT << ", vector) called with internal_nnz=" << mat.internal_nnz() << std::endl;
00058 
00059         viennacl::vector<SCALARTYPE> circ(mat.elements().size() * 2);
00060         viennacl::detail::fft::real_to_complex(mat.elements(), circ, mat.elements().size());
00061 
00062         viennacl::vector<SCALARTYPE> tmp(vec.size() * 2);
00063         viennacl::vector<SCALARTYPE> tmp2(vec.size() * 2);
00064 
00065         viennacl::detail::fft::real_to_complex(vec, tmp, vec.size());
00066         viennacl::linalg::convolve(circ, tmp, tmp2);
00067         viennacl::detail::fft::complex_to_real(tmp2, result, vec.size());
00068 
00069       }
00070 
00071   } //namespace linalg
00072 
00073 
00074 } //namespace viennacl
00075 
00076 
00077 #endif