DiagonalProduct.h
1 // This file is part of Eigen, a lightweight C++ template library
2 // for linear algebra.
3 //
4 // Copyright (C) 2008 Gael Guennebaud <gael.guennebaud@inria.fr>
5 // Copyright (C) 2007-2009 Benoit Jacob <jacob.benoit.1@gmail.com>
6 //
7 // This Source Code Form is subject to the terms of the Mozilla
8 // Public License v. 2.0. If a copy of the MPL was not distributed
9 // with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
10 
11 #ifndef EIGEN_DIAGONALPRODUCT_H
12 #define EIGEN_DIAGONALPRODUCT_H
13 
14 namespace Eigen {
15 
16 namespace internal {
17 template<typename MatrixType, typename DiagonalType, int ProductOrder>
18 struct traits<DiagonalProduct<MatrixType, DiagonalType, ProductOrder> >
19  : traits<MatrixType>
20 {
21  typedef typename scalar_product_traits<typename MatrixType::Scalar, typename DiagonalType::Scalar>::ReturnType Scalar;
22  enum {
23  RowsAtCompileTime = MatrixType::RowsAtCompileTime,
24  ColsAtCompileTime = MatrixType::ColsAtCompileTime,
25  MaxRowsAtCompileTime = MatrixType::MaxRowsAtCompileTime,
26  MaxColsAtCompileTime = MatrixType::MaxColsAtCompileTime,
27 
28  _StorageOrder = MatrixType::Flags & RowMajorBit ? RowMajor : ColMajor,
29  _PacketOnDiag = !((int(_StorageOrder) == RowMajor && int(ProductOrder) == OnTheLeft)
30  ||(int(_StorageOrder) == ColMajor && int(ProductOrder) == OnTheRight)),
31  _SameTypes = is_same<typename MatrixType::Scalar, typename DiagonalType::Scalar>::value,
32  // FIXME currently we need same types, but in the future the next rule should be the one
33  //_Vectorizable = bool(int(MatrixType::Flags)&PacketAccessBit) && ((!_PacketOnDiag) || (_SameTypes && bool(int(DiagonalType::Flags)&PacketAccessBit))),
34  _Vectorizable = bool(int(MatrixType::Flags)&PacketAccessBit) && _SameTypes && ((!_PacketOnDiag) || (bool(int(DiagonalType::Flags)&PacketAccessBit))),
35 
36  Flags = (HereditaryBits & (unsigned int)(MatrixType::Flags)) | (_Vectorizable ? PacketAccessBit : 0),
37  CoeffReadCost = NumTraits<Scalar>::MulCost + MatrixType::CoeffReadCost + DiagonalType::DiagonalVectorType::CoeffReadCost
38  };
39 };
40 }
41 
42 template<typename MatrixType, typename DiagonalType, int ProductOrder>
43 class DiagonalProduct : internal::no_assignment_operator,
44  public MatrixBase<DiagonalProduct<MatrixType, DiagonalType, ProductOrder> >
45 {
46  public:
47 
48  typedef MatrixBase<DiagonalProduct> Base;
49  EIGEN_DENSE_PUBLIC_INTERFACE(DiagonalProduct)
50 
51  inline DiagonalProduct(const MatrixType& matrix, const DiagonalType& diagonal)
52  : m_matrix(matrix), m_diagonal(diagonal)
53  {
54  eigen_assert(diagonal.diagonal().size() == (ProductOrder == OnTheLeft ? matrix.rows() : matrix.cols()));
55  }
56 
57  inline Index rows() const { return m_matrix.rows(); }
58  inline Index cols() const { return m_matrix.cols(); }
59 
60  const Scalar coeff(Index row, Index col) const
61  {
62  return m_diagonal.diagonal().coeff(ProductOrder == OnTheLeft ? row : col) * m_matrix.coeff(row, col);
63  }
64 
65  template<int LoadMode>
66  EIGEN_STRONG_INLINE PacketScalar packet(Index row, Index col) const
67  {
68  enum {
69  StorageOrder = Flags & RowMajorBit ? RowMajor : ColMajor
70  };
71  const Index indexInDiagonalVector = ProductOrder == OnTheLeft ? row : col;
72 
73  return packet_impl<LoadMode>(row,col,indexInDiagonalVector,typename internal::conditional<
74  ((int(StorageOrder) == RowMajor && int(ProductOrder) == OnTheLeft)
75  ||(int(StorageOrder) == ColMajor && int(ProductOrder) == OnTheRight)), internal::true_type, internal::false_type>::type());
76  }
77 
78  protected:
79  template<int LoadMode>
80  EIGEN_STRONG_INLINE PacketScalar packet_impl(Index row, Index col, Index id, internal::true_type) const
81  {
82  return internal::pmul(m_matrix.template packet<LoadMode>(row, col),
83  internal::pset1<PacketScalar>(m_diagonal.diagonal().coeff(id)));
84  }
85 
86  template<int LoadMode>
87  EIGEN_STRONG_INLINE PacketScalar packet_impl(Index row, Index col, Index id, internal::false_type) const
88  {
89  enum {
90  InnerSize = (MatrixType::Flags & RowMajorBit) ? MatrixType::ColsAtCompileTime : MatrixType::RowsAtCompileTime,
91  DiagonalVectorPacketLoadMode = (LoadMode == Aligned && ((InnerSize%16) == 0)) ? Aligned : Unaligned
92  };
93  return internal::pmul(m_matrix.template packet<LoadMode>(row, col),
94  m_diagonal.diagonal().template packet<DiagonalVectorPacketLoadMode>(id));
95  }
96 
97  typename MatrixType::Nested m_matrix;
98  typename DiagonalType::Nested m_diagonal;
99 };
100 
103 template<typename Derived>
104 template<typename DiagonalDerived>
105 inline const DiagonalProduct<Derived, DiagonalDerived, OnTheRight>
106 MatrixBase<Derived>::operator*(const DiagonalBase<DiagonalDerived> &diagonal) const
107 {
108  return DiagonalProduct<Derived, DiagonalDerived, OnTheRight>(derived(), diagonal.derived());
109 }
110 
113 template<typename DiagonalDerived>
114 template<typename MatrixDerived>
115 inline const DiagonalProduct<MatrixDerived, DiagonalDerived, OnTheLeft>
116 DiagonalBase<DiagonalDerived>::operator*(const MatrixBase<MatrixDerived> &matrix) const
117 {
118  return DiagonalProduct<MatrixDerived, DiagonalDerived, OnTheLeft>(matrix.derived(), derived());
119 }
120 
121 } // end namespace Eigen
122 
123 #endif // EIGEN_DIAGONALPRODUCT_H