mirror of
https://gitlab.com/libeigen/eigen.git
synced 2024-12-27 07:29:52 +08:00
58 lines
2.1 KiB
C++
58 lines
2.1 KiB
C++
// This file is part of Eigen, a lightweight C++ template library
|
|
// for linear algebra.
|
|
//
|
|
// Copyright (C) 2012 Chen-Pang He <jdh8@ms63.hinet.net>
|
|
//
|
|
// This Source Code Form is subject to the terms of the Mozilla
|
|
// Public License v. 2.0. If a copy of the MPL was not distributed
|
|
// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
|
|
|
|
#ifndef EIGEN_RANK2UPDATE_H
|
|
#define EIGEN_RANK2UPDATE_H
|
|
|
|
namespace internal {
|
|
|
|
/* Optimized selfadjoint matrix += alpha * uv' + conj(alpha)*vu'
|
|
* This is the low-level version of SelfadjointRank2Update.h
|
|
*/
|
|
template<typename Scalar, typename Index, int UpLo>
|
|
struct rank2_update_selector
|
|
{
|
|
static void run(Index size, Scalar* mat, Index stride, const Scalar* u, const Scalar* v, Scalar alpha)
|
|
{
|
|
typedef Map<const Matrix<Scalar,Dynamic,1> > OtherMap;
|
|
for (Index i=0; i<size; ++i)
|
|
{
|
|
Map<Matrix<Scalar,Dynamic,1> >(mat+stride*i+(UpLo==Lower ? i : 0), UpLo==Lower ? size-i : (i+1)) +=
|
|
numext::conj(alpha) * numext::conj(u[i]) * OtherMap(v+(UpLo==Lower ? i : 0), UpLo==Lower ? size-i : (i+1))
|
|
+ alpha * numext::conj(v[i]) * OtherMap(u+(UpLo==Lower ? i : 0), UpLo==Lower ? size-i : (i+1));
|
|
}
|
|
}
|
|
};
|
|
|
|
/* Optimized selfadjoint matrix += alpha * uv' + conj(alpha)*vu'
|
|
* The matrix is in packed form.
|
|
*/
|
|
template<typename Scalar, typename Index, int UpLo>
|
|
struct packed_rank2_update_selector
|
|
{
|
|
static void run(Index size, Scalar* mat, const Scalar* u, const Scalar* v, Scalar alpha)
|
|
{
|
|
typedef Map<const Matrix<Scalar,Dynamic,1> > OtherMap;
|
|
Index offset = 0;
|
|
for (Index i=0; i<size; ++i)
|
|
{
|
|
Map<Matrix<Scalar,Dynamic,1> >(mat+offset, UpLo==Lower ? size-i : (i+1)) +=
|
|
numext::conj(alpha) * numext::conj(u[i]) * OtherMap(v+(UpLo==Lower ? i : 0), UpLo==Lower ? size-i : (i+1))
|
|
+ alpha * numext::conj(v[i]) * OtherMap(u+(UpLo==Lower ? i : 0), UpLo==Lower ? size-i : (i+1));
|
|
//FIXME This should be handled outside.
|
|
mat[offset+(UpLo==Lower ? 0 : i)] = numext::real(mat[offset+(UpLo==Lower ? 0 : i)]);
|
|
offset += UpLo==Lower ? size-i : (i+1);
|
|
}
|
|
}
|
|
};
|
|
|
|
} // end namespace internal
|
|
|
|
#endif // EIGEN_RANK2UPDATE_H
|