MYNT-EYE-S-SDK/3rdparty/eigen3/Eigen/src/SparseLU/SparseLU_kernel_bmod.h
2019-01-03 16:25:18 +08:00

131 lines
5.6 KiB
C++

// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// Copyright (C) 2012 Désiré Nuentsa-Wakam <desire.nuentsa_wakam@inria.fr>
// Copyright (C) 2012 Gael Guennebaud <gael.guennebaud@inria.fr>
//
// 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 SPARSELU_KERNEL_BMOD_H
#define SPARSELU_KERNEL_BMOD_H
namespace Eigen {
namespace internal {
/**
* \brief Performs numeric block updates from a given supernode to a single column
*
* \param segsize Size of the segment (and blocks ) to use for updates
* \param[in,out] dense Packed values of the original matrix
* \param tempv temporary vector to use for updates
* \param lusup array containing the supernodes
* \param lda Leading dimension in the supernode
* \param nrow Number of rows in the rectangular part of the supernode
* \param lsub compressed row subscripts of supernodes
* \param lptr pointer to the first column of the current supernode in lsub
* \param no_zeros Number of nonzeros elements before the diagonal part of the supernode
* \return 0 on success
*/
template <int SegSizeAtCompileTime> struct LU_kernel_bmod
{
template <typename BlockScalarVector, typename ScalarVector, typename IndexVector, typename Index>
static EIGEN_DONT_INLINE void run(const int segsize, BlockScalarVector& dense, ScalarVector& tempv, ScalarVector& lusup, Index& luptr, const Index lda,
const Index nrow, IndexVector& lsub, const Index lptr, const Index no_zeros);
};
template <int SegSizeAtCompileTime>
template <typename BlockScalarVector, typename ScalarVector, typename IndexVector, typename Index>
EIGEN_DONT_INLINE void LU_kernel_bmod<SegSizeAtCompileTime>::run(const int segsize, BlockScalarVector& dense, ScalarVector& tempv, ScalarVector& lusup, Index& luptr, const Index lda,
const Index nrow, IndexVector& lsub, const Index lptr, const Index no_zeros)
{
typedef typename ScalarVector::Scalar Scalar;
// First, copy U[*,j] segment from dense(*) to tempv(*)
// The result of triangular solve is in tempv[*];
// The result of matric-vector update is in dense[*]
Index isub = lptr + no_zeros;
int i;
Index irow;
for (i = 0; i < ((SegSizeAtCompileTime==Dynamic)?segsize:SegSizeAtCompileTime); i++)
{
irow = lsub(isub);
tempv(i) = dense(irow);
++isub;
}
// Dense triangular solve -- start effective triangle
luptr += lda * no_zeros + no_zeros;
// Form Eigen matrix and vector
Map<Matrix<Scalar,SegSizeAtCompileTime,SegSizeAtCompileTime, ColMajor>, 0, OuterStride<> > A( &(lusup.data()[luptr]), segsize, segsize, OuterStride<>(lda) );
Map<Matrix<Scalar,SegSizeAtCompileTime,1> > u(tempv.data(), segsize);
u = A.template triangularView<UnitLower>().solve(u);
// Dense matrix-vector product y <-- B*x
luptr += segsize;
const Index PacketSize = internal::packet_traits<Scalar>::size;
Index ldl = internal::first_multiple(nrow, PacketSize);
Map<Matrix<Scalar,Dynamic,SegSizeAtCompileTime, ColMajor>, 0, OuterStride<> > B( &(lusup.data()[luptr]), nrow, segsize, OuterStride<>(lda) );
Index aligned_offset = internal::first_aligned(tempv.data()+segsize, PacketSize);
Index aligned_with_B_offset = (PacketSize-internal::first_aligned(B.data(), PacketSize))%PacketSize;
Map<Matrix<Scalar,Dynamic,1>, 0, OuterStride<> > l(tempv.data()+segsize+aligned_offset+aligned_with_B_offset, nrow, OuterStride<>(ldl) );
l.setZero();
internal::sparselu_gemm<Scalar>(l.rows(), l.cols(), B.cols(), B.data(), B.outerStride(), u.data(), u.outerStride(), l.data(), l.outerStride());
// Scatter tempv[] into SPA dense[] as a temporary storage
isub = lptr + no_zeros;
for (i = 0; i < ((SegSizeAtCompileTime==Dynamic)?segsize:SegSizeAtCompileTime); i++)
{
irow = lsub(isub++);
dense(irow) = tempv(i);
}
// Scatter l into SPA dense[]
for (i = 0; i < nrow; i++)
{
irow = lsub(isub++);
dense(irow) -= l(i);
}
}
template <> struct LU_kernel_bmod<1>
{
template <typename BlockScalarVector, typename ScalarVector, typename IndexVector, typename Index>
static EIGEN_DONT_INLINE void run(const int /*segsize*/, BlockScalarVector& dense, ScalarVector& /*tempv*/, ScalarVector& lusup, Index& luptr,
const Index lda, const Index nrow, IndexVector& lsub, const Index lptr, const Index no_zeros);
};
template <typename BlockScalarVector, typename ScalarVector, typename IndexVector, typename Index>
EIGEN_DONT_INLINE void LU_kernel_bmod<1>::run(const int /*segsize*/, BlockScalarVector& dense, ScalarVector& /*tempv*/, ScalarVector& lusup, Index& luptr,
const Index lda, const Index nrow, IndexVector& lsub, const Index lptr, const Index no_zeros)
{
typedef typename ScalarVector::Scalar Scalar;
Scalar f = dense(lsub(lptr + no_zeros));
luptr += lda * no_zeros + no_zeros + 1;
const Scalar* a(lusup.data() + luptr);
const /*typename IndexVector::Scalar*/Index* irow(lsub.data()+lptr + no_zeros + 1);
Index i = 0;
for (; i+1 < nrow; i+=2)
{
Index i0 = *(irow++);
Index i1 = *(irow++);
Scalar a0 = *(a++);
Scalar a1 = *(a++);
Scalar d0 = dense.coeff(i0);
Scalar d1 = dense.coeff(i1);
d0 -= f*a0;
d1 -= f*a1;
dense.coeffRef(i0) = d0;
dense.coeffRef(i1) = d1;
}
if(i<nrow)
dense.coeffRef(*(irow++)) -= f * *(a++);
}
} // end namespace internal
} // end namespace Eigen
#endif // SPARSELU_KERNEL_BMOD_H