1//=====================================================
2// Copyright (C) 2014 Benoit Steiner <benoit.steiner.goog@gmail.com>
3//=====================================================
4//
5// This Source Code Form is subject to the terms of the Mozilla
6// Public License v. 2.0. If a copy of the MPL was not distributed
7// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
8//
9#ifndef TENSOR_INTERFACE_HH
10#define TENSOR_INTERFACE_HH
11
12#include <unsupported/Eigen/CXX11/Tensor>
13#include <vector>
14#include "btl.hh"
15
16using namespace Eigen;
17
18template<class real>
19class tensor_interface
20{
21public :
22  typedef real real_type;
23  typedef typename Eigen::Tensor<real,2>::Index Index;
24
25  typedef std::vector<real> stl_vector;
26  typedef std::vector<stl_vector> stl_matrix;
27
28  typedef Eigen::Tensor<real,2> gene_matrix;
29  typedef Eigen::Tensor<real,1> gene_vector;
30
31
32  static inline std::string name( void )
33  {
34    return EIGEN_MAKESTRING(BTL_PREFIX);
35  }
36
37  static void free_matrix(gene_matrix & /*A*/, int /*N*/) {}
38
39  static void free_vector(gene_vector & /*B*/) {}
40
41  static BTL_DONT_INLINE void matrix_from_stl(gene_matrix & A, stl_matrix & A_stl){
42    A.resize(Eigen::array<Index,2>(A_stl[0].size(), A_stl.size()));
43
44    for (unsigned int j=0; j<A_stl.size() ; j++){
45      for (unsigned int i=0; i<A_stl[j].size() ; i++){
46        A.coeffRef(Eigen::array<Index,2>(i,j)) = A_stl[j][i];
47      }
48    }
49  }
50
51  static BTL_DONT_INLINE  void vector_from_stl(gene_vector & B, stl_vector & B_stl){
52    B.resize(B_stl.size());
53
54    for (unsigned int i=0; i<B_stl.size() ; i++){
55      B.coeffRef(i) = B_stl[i];
56    }
57  }
58
59  static BTL_DONT_INLINE  void vector_to_stl(gene_vector & B, stl_vector & B_stl){
60    for (unsigned int i=0; i<B_stl.size() ; i++){
61      B_stl[i] = B.coeff(i);
62    }
63  }
64
65  static BTL_DONT_INLINE  void matrix_to_stl(gene_matrix & A, stl_matrix & A_stl){
66    int  N=A_stl.size();
67
68    for (int j=0;j<N;j++){
69      A_stl[j].resize(N);
70      for (int i=0;i<N;i++){
71        A_stl[j][i] = A.coeff(Eigen::array<Index,2>(i,j));
72      }
73    }
74  }
75
76  static inline void matrix_matrix_product(const gene_matrix & A, const gene_matrix & B, gene_matrix & X, int  /*N*/){
77    typedef typename Eigen::Tensor<real_type, 1>::DimensionPair DimPair;
78    const Eigen::array<DimPair, 1> dims(DimPair(1, 0));
79    X/*.noalias()*/ = A.contract(B, dims);
80  }
81
82  static inline void matrix_vector_product(const gene_matrix & A, const gene_vector & B, gene_vector & X, int  /*N*/){
83    typedef typename Eigen::Tensor<real_type, 1>::DimensionPair DimPair;
84    const Eigen::array<DimPair, 1> dims(DimPair(1, 0));
85    X/*.noalias()*/ = A.contract(B, dims);
86  }
87
88  static inline void axpy(real coef, const gene_vector & X, gene_vector & Y, int  /*N*/){
89    Y += X.constant(coef) * X;
90  }
91
92  static inline void axpby(real a, const gene_vector & X, real b, gene_vector & Y, int  /*N*/){
93    Y = X.constant(a)*X + Y.constant(b)*Y;
94  }
95
96  static EIGEN_DONT_INLINE void copy_matrix(const gene_matrix & source, gene_matrix & cible, int  /*N*/){
97    cible = source;
98  }
99
100  static EIGEN_DONT_INLINE void copy_vector(const gene_vector & source, gene_vector & cible, int  /*N*/){
101    cible = source;
102  }
103};
104
105#endif
106