1 // This file is part of Eigen, a lightweight C++ template library
2 // for linear algebra.
3 //
4 // Copyright (C) 2009 Gael Guennebaud <gael.guennebaud@inria.fr>
5 //
6 // This Source Code Form is subject to the terms of the Mozilla
7 // Public License v. 2.0. If a copy of the MPL was not distributed
8 // with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
9 
10 #ifndef EIGEN_SELFADJOINT_PRODUCT_H
11 #define EIGEN_SELFADJOINT_PRODUCT_H
12 
13 /**********************************************************************
14 * This file implements a self adjoint product: C += A A^T updating only
15 * half of the selfadjoint matrix C.
16 * It corresponds to the level 3 SYRK and level 2 SYR Blas routines.
17 **********************************************************************/
18 
19 namespace Eigen {
20 
21 
22 template<typename Scalar, typename Index, int UpLo, bool ConjLhs, bool ConjRhs>
23 struct selfadjoint_rank1_update<Scalar,Index,ColMajor,UpLo,ConjLhs,ConjRhs>
24 {
25   static void run(Index size, Scalar* mat, Index stride, const Scalar* vecX, const Scalar* vecY, const Scalar& alpha)
26   {
27     internal::conj_if<ConjRhs> cj;
28     typedef Map<const Matrix<Scalar,Dynamic,1> > OtherMap;
29     typedef typename internal::conditional<ConjLhs,typename OtherMap::ConjugateReturnType,const OtherMap&>::type ConjLhsType;
30     for (Index i=0; i<size; ++i)
31     {
32       Map<Matrix<Scalar,Dynamic,1> >(mat+stride*i+(UpLo==Lower ? i : 0), (UpLo==Lower ? size-i : (i+1)))
33           += (alpha * cj(vecY[i])) * ConjLhsType(OtherMap(vecX+(UpLo==Lower ? i : 0),UpLo==Lower ? size-i : (i+1)));
34     }
35   }
36 };
37 
38 template<typename Scalar, typename Index, int UpLo, bool ConjLhs, bool ConjRhs>
39 struct selfadjoint_rank1_update<Scalar,Index,RowMajor,UpLo,ConjLhs,ConjRhs>
40 {
41   static void run(Index size, Scalar* mat, Index stride, const Scalar* vecX, const Scalar* vecY, const Scalar& alpha)
42   {
43     selfadjoint_rank1_update<Scalar,Index,ColMajor,UpLo==Lower?Upper:Lower,ConjRhs,ConjLhs>::run(size,mat,stride,vecY,vecX,alpha);
44   }
45 };
46 
47 template<typename MatrixType, typename OtherType, int UpLo, bool OtherIsVector = OtherType::IsVectorAtCompileTime>
48 struct selfadjoint_product_selector;
49 
50 template<typename MatrixType, typename OtherType, int UpLo>
51 struct selfadjoint_product_selector<MatrixType,OtherType,UpLo,true>
52 {
53   static void run(MatrixType& mat, const OtherType& other, const typename MatrixType::Scalar& alpha)
54   {
55     typedef typename MatrixType::Scalar Scalar;
56     typedef internal::blas_traits<OtherType> OtherBlasTraits;
57     typedef typename OtherBlasTraits::DirectLinearAccessType ActualOtherType;
58     typedef typename internal::remove_all<ActualOtherType>::type _ActualOtherType;
59     typename internal::add_const_on_value_type<ActualOtherType>::type actualOther = OtherBlasTraits::extract(other.derived());
60 
61     Scalar actualAlpha = alpha * OtherBlasTraits::extractScalarFactor(other.derived());
62 
63     enum {
64       StorageOrder = (internal::traits<MatrixType>::Flags&RowMajorBit) ? RowMajor : ColMajor,
65       UseOtherDirectly = _ActualOtherType::InnerStrideAtCompileTime==1
66     };
67     internal::gemv_static_vector_if<Scalar,OtherType::SizeAtCompileTime,OtherType::MaxSizeAtCompileTime,!UseOtherDirectly> static_other;
68 
69     ei_declare_aligned_stack_constructed_variable(Scalar, actualOtherPtr, other.size(),
70       (UseOtherDirectly ? const_cast<Scalar*>(actualOther.data()) : static_other.data()));
71 
72     if(!UseOtherDirectly)
73       Map<typename _ActualOtherType::PlainObject>(actualOtherPtr, actualOther.size()) = actualOther;
74 
75     selfadjoint_rank1_update<Scalar,Index,StorageOrder,UpLo,
76                               OtherBlasTraits::NeedToConjugate  && NumTraits<Scalar>::IsComplex,
77                             (!OtherBlasTraits::NeedToConjugate) && NumTraits<Scalar>::IsComplex>
78           ::run(other.size(), mat.data(), mat.outerStride(), actualOtherPtr, actualOtherPtr, actualAlpha);
79   }
80 };
81 
82 template<typename MatrixType, typename OtherType, int UpLo>
83 struct selfadjoint_product_selector<MatrixType,OtherType,UpLo,false>
84 {
85   static void run(MatrixType& mat, const OtherType& other, const typename MatrixType::Scalar& alpha)
86   {
87     typedef typename MatrixType::Scalar Scalar;
88     typedef internal::blas_traits<OtherType> OtherBlasTraits;
89     typedef typename OtherBlasTraits::DirectLinearAccessType ActualOtherType;
90     typedef typename internal::remove_all<ActualOtherType>::type _ActualOtherType;
91     typename internal::add_const_on_value_type<ActualOtherType>::type actualOther = OtherBlasTraits::extract(other.derived());
92 
93     Scalar actualAlpha = alpha * OtherBlasTraits::extractScalarFactor(other.derived());
94 
95     enum {
96       IsRowMajor = (internal::traits<MatrixType>::Flags&RowMajorBit) ? 1 : 0,
97       OtherIsRowMajor = _ActualOtherType::Flags&RowMajorBit ? 1 : 0
98     };
99 
100     Index size = mat.cols();
101     Index depth = actualOther.cols();
102 
103     typedef internal::gemm_blocking_space<IsRowMajor ? RowMajor : ColMajor,Scalar,Scalar,
104               MatrixType::MaxColsAtCompileTime, MatrixType::MaxColsAtCompileTime, _ActualOtherType::MaxColsAtCompileTime> BlockingType;
105 
106     BlockingType blocking(size, size, depth, 1, false);
107 
108 
109     internal::general_matrix_matrix_triangular_product<Index,
110       Scalar, OtherIsRowMajor ? RowMajor : ColMajor,   OtherBlasTraits::NeedToConjugate  && NumTraits<Scalar>::IsComplex,
111       Scalar, OtherIsRowMajor ? ColMajor : RowMajor, (!OtherBlasTraits::NeedToConjugate) && NumTraits<Scalar>::IsComplex,
112       IsRowMajor ? RowMajor : ColMajor, UpLo>
113       ::run(size, depth,
114             &actualOther.coeffRef(0,0), actualOther.outerStride(), &actualOther.coeffRef(0,0), actualOther.outerStride(),
115             mat.data(), mat.outerStride(), actualAlpha, blocking);
116   }
117 };
118 
119 // high level API
120 
121 template<typename MatrixType, unsigned int UpLo>
122 template<typename DerivedU>
123 SelfAdjointView<MatrixType,UpLo>& SelfAdjointView<MatrixType,UpLo>
124 ::rankUpdate(const MatrixBase<DerivedU>& u, const Scalar& alpha)
125 {
126   selfadjoint_product_selector<MatrixType,DerivedU,UpLo>::run(_expression().const_cast_derived(), u.derived(), alpha);
127 
128   return *this;
129 }
130 
131 } // end namespace Eigen
132 
133 #endif // EIGEN_SELFADJOINT_PRODUCT_H
134