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_SELFADJOINT_PACKED_PRODUCT_H
11#define EIGEN_SELFADJOINT_PACKED_PRODUCT_H
12
13namespace internal {
14
15/* Optimized matrix += alpha * uv'
16 * The matrix is in packed form.
17 */
18template<typename Scalar, typename Index, int StorageOrder, int UpLo, bool ConjLhs, bool ConjRhs>
19struct selfadjoint_packed_rank1_update;
20
21template<typename Scalar, typename Index, int UpLo, bool ConjLhs, bool ConjRhs>
22struct selfadjoint_packed_rank1_update<Scalar,Index,ColMajor,UpLo,ConjLhs,ConjRhs>
23{
24  typedef typename NumTraits<Scalar>::Real RealScalar;
25  static void run(Index size, Scalar* mat, const Scalar* vec, RealScalar alpha)
26  {
27    typedef Map<const Matrix<Scalar,Dynamic,1> > OtherMap;
28    typedef typename conj_expr_if<ConjLhs,OtherMap>::type ConjRhsType;
29    conj_if<ConjRhs> cj;
30
31    for (Index i=0; i<size; ++i)
32    {
33      Map<Matrix<Scalar,Dynamic,1> >(mat, UpLo==Lower ? size-i : (i+1)) += alpha * cj(vec[i]) * ConjRhsType(OtherMap(vec+(UpLo==Lower ? i : 0), UpLo==Lower ? size-i : (i+1)));
34      //FIXME This should be handled outside.
35      mat[UpLo==Lower ? 0 : i] = numext::real(mat[UpLo==Lower ? 0 : i]);
36      mat += UpLo==Lower ? size-i : (i+1);
37    }
38  }
39};
40
41template<typename Scalar, typename Index, int UpLo, bool ConjLhs, bool ConjRhs>
42struct selfadjoint_packed_rank1_update<Scalar,Index,RowMajor,UpLo,ConjLhs,ConjRhs>
43{
44  typedef typename NumTraits<Scalar>::Real RealScalar;
45  static void run(Index size, Scalar* mat, const Scalar* vec, RealScalar alpha)
46  {
47    selfadjoint_packed_rank1_update<Scalar,Index,ColMajor,UpLo==Lower?Upper:Lower,ConjRhs,ConjLhs>::run(size,mat,vec,alpha);
48  }
49};
50
51} // end namespace internal
52
53#endif // EIGEN_SELFADJOINT_PACKED_PRODUCT_H
54