1 // This file is part of Eigen, a lightweight C++ template library
2 // for linear algebra.
3 //
4 // Copyright (C) 2012 Chen-Pang He <jdh8@ms63.hinet.net>
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_PACKED_TRIANGULAR_MATRIX_VECTOR_H
11 #define EIGEN_PACKED_TRIANGULAR_MATRIX_VECTOR_H
12 
13 namespace internal {
14 
15 template<typename Index, int Mode, typename LhsScalar, bool ConjLhs, typename RhsScalar, bool ConjRhs, int StorageOrder>
16 struct packed_triangular_matrix_vector_product;
17 
18 template<typename Index, int Mode, typename LhsScalar, bool ConjLhs, typename RhsScalar, bool ConjRhs>
19 struct packed_triangular_matrix_vector_product<Index,Mode,LhsScalar,ConjLhs,RhsScalar,ConjRhs,ColMajor>
20 {
21   typedef typename scalar_product_traits<LhsScalar, RhsScalar>::ReturnType ResScalar;
22   enum {
23     IsLower     = (Mode & Lower)   ==Lower,
24     HasUnitDiag = (Mode & UnitDiag)==UnitDiag,
25     HasZeroDiag = (Mode & ZeroDiag)==ZeroDiag
26   };
27   static void run(Index size, const LhsScalar* lhs, const RhsScalar* rhs, ResScalar* res, ResScalar alpha)
28   {
29     internal::conj_if<ConjRhs> cj;
30     typedef Map<const Matrix<LhsScalar,Dynamic,1> > LhsMap;
31     typedef typename conj_expr_if<ConjLhs,LhsMap>::type ConjLhsType;
32     typedef Map<Matrix<ResScalar,Dynamic,1> > ResMap;
33 
34     for (Index i=0; i<size; ++i)
35     {
36       Index s = IsLower&&(HasUnitDiag||HasZeroDiag) ? 1 : 0;
37       Index r = IsLower ? size-i: i+1;
38       if (EIGEN_IMPLIES(HasUnitDiag||HasZeroDiag, (--r)>0))
39 	ResMap(res+(IsLower ? s+i : 0),r) += alpha * cj(rhs[i]) * ConjLhsType(LhsMap(lhs+s,r));
40       if (HasUnitDiag)
41 	res[i] += alpha * cj(rhs[i]);
42       lhs += IsLower ? size-i: i+1;
43     }
44   };
45 };
46 
47 template<typename Index, int Mode, typename LhsScalar, bool ConjLhs, typename RhsScalar, bool ConjRhs>
48 struct packed_triangular_matrix_vector_product<Index,Mode,LhsScalar,ConjLhs,RhsScalar,ConjRhs,RowMajor>
49 {
50   typedef typename scalar_product_traits<LhsScalar, RhsScalar>::ReturnType ResScalar;
51   enum {
52     IsLower     = (Mode & Lower)   ==Lower,
53     HasUnitDiag = (Mode & UnitDiag)==UnitDiag,
54     HasZeroDiag = (Mode & ZeroDiag)==ZeroDiag
55   };
56   static void run(Index size, const LhsScalar* lhs, const RhsScalar* rhs, ResScalar* res, ResScalar alpha)
57   {
58     internal::conj_if<ConjRhs> cj;
59     typedef Map<const Matrix<LhsScalar,Dynamic,1> > LhsMap;
60     typedef typename conj_expr_if<ConjLhs,LhsMap>::type ConjLhsType;
61     typedef Map<const Matrix<RhsScalar,Dynamic,1> > RhsMap;
62     typedef typename conj_expr_if<ConjRhs,RhsMap>::type ConjRhsType;
63 
64     for (Index i=0; i<size; ++i)
65     {
66       Index s = !IsLower&&(HasUnitDiag||HasZeroDiag) ? 1 : 0;
67       Index r = IsLower ? i+1 : size-i;
68       if (EIGEN_IMPLIES(HasUnitDiag||HasZeroDiag, (--r)>0))
69 	res[i] += alpha * (ConjLhsType(LhsMap(lhs+s,r)).cwiseProduct(ConjRhsType(RhsMap(rhs+(IsLower ? 0 : s+i),r)))).sum();
70       if (HasUnitDiag)
71 	res[i] += alpha * cj(rhs[i]);
72       lhs += IsLower ? i+1 : size-i;
73     }
74   };
75 };
76 
77 } // end namespace internal
78 
79 #endif // EIGEN_PACKED_TRIANGULAR_MATRIX_VECTOR_H
80