671 lines
23 KiB
C++
671 lines
23 KiB
C++
|
// Ceres Solver - A fast non-linear least squares minimizer
|
||
|
// Copyright 2015 Google Inc. All rights reserved.
|
||
|
// http://ceres-solver.org/
|
||
|
//
|
||
|
// Redistribution and use in source and binary forms, with or without
|
||
|
// modification, are permitted provided that the following conditions are met:
|
||
|
//
|
||
|
// * Redistributions of source code must retain the above copyright notice,
|
||
|
// this list of conditions and the following disclaimer.
|
||
|
// * Redistributions in binary form must reproduce the above copyright notice,
|
||
|
// this list of conditions and the following disclaimer in the documentation
|
||
|
// and/or other materials provided with the distribution.
|
||
|
// * Neither the name of Google Inc. nor the names of its contributors may be
|
||
|
// used to endorse or promote products derived from this software without
|
||
|
// specific prior written permission.
|
||
|
//
|
||
|
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
||
|
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
||
|
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
||
|
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
|
||
|
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
||
|
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
||
|
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
||
|
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
||
|
// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
||
|
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
||
|
// POSSIBILITY OF SUCH DAMAGE.
|
||
|
//
|
||
|
// Author: sameeragarwal@google.com (Sameer Agarwal)
|
||
|
|
||
|
#include "ceres/internal/port.h"
|
||
|
|
||
|
#include <algorithm>
|
||
|
#include <ctime>
|
||
|
#include <set>
|
||
|
#include <vector>
|
||
|
|
||
|
#include "ceres/block_random_access_dense_matrix.h"
|
||
|
#include "ceres/block_random_access_matrix.h"
|
||
|
#include "ceres/block_random_access_sparse_matrix.h"
|
||
|
#include "ceres/block_sparse_matrix.h"
|
||
|
#include "ceres/block_structure.h"
|
||
|
#include "ceres/conjugate_gradients_solver.h"
|
||
|
#include "ceres/cxsparse.h"
|
||
|
#include "ceres/detect_structure.h"
|
||
|
#include "ceres/internal/eigen.h"
|
||
|
#include "ceres/internal/scoped_ptr.h"
|
||
|
#include "ceres/lapack.h"
|
||
|
#include "ceres/linear_solver.h"
|
||
|
#include "ceres/schur_complement_solver.h"
|
||
|
#include "ceres/suitesparse.h"
|
||
|
#include "ceres/triplet_sparse_matrix.h"
|
||
|
#include "ceres/types.h"
|
||
|
#include "ceres/wall_time.h"
|
||
|
#include "Eigen/Dense"
|
||
|
#include "Eigen/SparseCore"
|
||
|
|
||
|
namespace ceres {
|
||
|
namespace internal {
|
||
|
|
||
|
using std::make_pair;
|
||
|
using std::pair;
|
||
|
using std::set;
|
||
|
using std::vector;
|
||
|
|
||
|
namespace {
|
||
|
|
||
|
class BlockRandomAccessSparseMatrixAdapter : public LinearOperator {
|
||
|
public:
|
||
|
explicit BlockRandomAccessSparseMatrixAdapter(
|
||
|
const BlockRandomAccessSparseMatrix& m)
|
||
|
: m_(m) {
|
||
|
}
|
||
|
|
||
|
virtual ~BlockRandomAccessSparseMatrixAdapter() {}
|
||
|
|
||
|
// y = y + Ax;
|
||
|
virtual void RightMultiply(const double* x, double* y) const {
|
||
|
m_.SymmetricRightMultiply(x, y);
|
||
|
}
|
||
|
|
||
|
// y = y + A'x;
|
||
|
virtual void LeftMultiply(const double* x, double* y) const {
|
||
|
m_.SymmetricRightMultiply(x, y);
|
||
|
}
|
||
|
|
||
|
virtual int num_rows() const { return m_.num_rows(); }
|
||
|
virtual int num_cols() const { return m_.num_rows(); }
|
||
|
|
||
|
private:
|
||
|
const BlockRandomAccessSparseMatrix& m_;
|
||
|
};
|
||
|
|
||
|
class BlockRandomAccessDiagonalMatrixAdapter : public LinearOperator {
|
||
|
public:
|
||
|
explicit BlockRandomAccessDiagonalMatrixAdapter(
|
||
|
const BlockRandomAccessDiagonalMatrix& m)
|
||
|
: m_(m) {
|
||
|
}
|
||
|
|
||
|
virtual ~BlockRandomAccessDiagonalMatrixAdapter() {}
|
||
|
|
||
|
// y = y + Ax;
|
||
|
virtual void RightMultiply(const double* x, double* y) const {
|
||
|
m_.RightMultiply(x, y);
|
||
|
}
|
||
|
|
||
|
// y = y + A'x;
|
||
|
virtual void LeftMultiply(const double* x, double* y) const {
|
||
|
m_.RightMultiply(x, y);
|
||
|
}
|
||
|
|
||
|
virtual int num_rows() const { return m_.num_rows(); }
|
||
|
virtual int num_cols() const { return m_.num_rows(); }
|
||
|
|
||
|
private:
|
||
|
const BlockRandomAccessDiagonalMatrix& m_;
|
||
|
};
|
||
|
|
||
|
} // namespace
|
||
|
|
||
|
LinearSolver::Summary SchurComplementSolver::SolveImpl(
|
||
|
BlockSparseMatrix* A,
|
||
|
const double* b,
|
||
|
const LinearSolver::PerSolveOptions& per_solve_options,
|
||
|
double* x) {
|
||
|
EventLogger event_logger("SchurComplementSolver::Solve");
|
||
|
|
||
|
if (eliminator_.get() == NULL) {
|
||
|
InitStorage(A->block_structure());
|
||
|
DetectStructure(*A->block_structure(),
|
||
|
options_.elimination_groups[0],
|
||
|
&options_.row_block_size,
|
||
|
&options_.e_block_size,
|
||
|
&options_.f_block_size);
|
||
|
eliminator_.reset(CHECK_NOTNULL(SchurEliminatorBase::Create(options_)));
|
||
|
eliminator_->Init(options_.elimination_groups[0], A->block_structure());
|
||
|
};
|
||
|
std::fill(x, x + A->num_cols(), 0.0);
|
||
|
event_logger.AddEvent("Setup");
|
||
|
|
||
|
eliminator_->Eliminate(A, b, per_solve_options.D, lhs_.get(), rhs_.get());
|
||
|
event_logger.AddEvent("Eliminate");
|
||
|
|
||
|
double* reduced_solution = x + A->num_cols() - lhs_->num_cols();
|
||
|
const LinearSolver::Summary summary =
|
||
|
SolveReducedLinearSystem(per_solve_options, reduced_solution);
|
||
|
event_logger.AddEvent("ReducedSolve");
|
||
|
|
||
|
if (summary.termination_type == LINEAR_SOLVER_SUCCESS) {
|
||
|
eliminator_->BackSubstitute(A, b, per_solve_options.D, reduced_solution, x);
|
||
|
event_logger.AddEvent("BackSubstitute");
|
||
|
}
|
||
|
|
||
|
return summary;
|
||
|
}
|
||
|
|
||
|
// Initialize a BlockRandomAccessDenseMatrix to store the Schur
|
||
|
// complement.
|
||
|
void DenseSchurComplementSolver::InitStorage(
|
||
|
const CompressedRowBlockStructure* bs) {
|
||
|
const int num_eliminate_blocks = options().elimination_groups[0];
|
||
|
const int num_col_blocks = bs->cols.size();
|
||
|
|
||
|
vector<int> blocks(num_col_blocks - num_eliminate_blocks, 0);
|
||
|
for (int i = num_eliminate_blocks, j = 0;
|
||
|
i < num_col_blocks;
|
||
|
++i, ++j) {
|
||
|
blocks[j] = bs->cols[i].size;
|
||
|
}
|
||
|
|
||
|
set_lhs(new BlockRandomAccessDenseMatrix(blocks));
|
||
|
set_rhs(new double[lhs()->num_rows()]);
|
||
|
}
|
||
|
|
||
|
// Solve the system Sx = r, assuming that the matrix S is stored in a
|
||
|
// BlockRandomAccessDenseMatrix. The linear system is solved using
|
||
|
// Eigen's Cholesky factorization.
|
||
|
LinearSolver::Summary
|
||
|
DenseSchurComplementSolver::SolveReducedLinearSystem(
|
||
|
const LinearSolver::PerSolveOptions& per_solve_options,
|
||
|
double* solution) {
|
||
|
LinearSolver::Summary summary;
|
||
|
summary.num_iterations = 0;
|
||
|
summary.termination_type = LINEAR_SOLVER_SUCCESS;
|
||
|
summary.message = "Success.";
|
||
|
|
||
|
const BlockRandomAccessDenseMatrix* m =
|
||
|
down_cast<const BlockRandomAccessDenseMatrix*>(lhs());
|
||
|
const int num_rows = m->num_rows();
|
||
|
|
||
|
// The case where there are no f blocks, and the system is block
|
||
|
// diagonal.
|
||
|
if (num_rows == 0) {
|
||
|
return summary;
|
||
|
}
|
||
|
|
||
|
summary.num_iterations = 1;
|
||
|
|
||
|
if (options().dense_linear_algebra_library_type == EIGEN) {
|
||
|
Eigen::LLT<Matrix, Eigen::Upper> llt =
|
||
|
ConstMatrixRef(m->values(), num_rows, num_rows)
|
||
|
.selfadjointView<Eigen::Upper>()
|
||
|
.llt();
|
||
|
if (llt.info() != Eigen::Success) {
|
||
|
summary.termination_type = LINEAR_SOLVER_FAILURE;
|
||
|
summary.message =
|
||
|
"Eigen failure. Unable to perform dense Cholesky factorization.";
|
||
|
return summary;
|
||
|
}
|
||
|
|
||
|
VectorRef(solution, num_rows) = llt.solve(ConstVectorRef(rhs(), num_rows));
|
||
|
} else {
|
||
|
VectorRef(solution, num_rows) = ConstVectorRef(rhs(), num_rows);
|
||
|
summary.termination_type =
|
||
|
LAPACK::SolveInPlaceUsingCholesky(num_rows,
|
||
|
m->values(),
|
||
|
solution,
|
||
|
&summary.message);
|
||
|
}
|
||
|
|
||
|
return summary;
|
||
|
}
|
||
|
|
||
|
SparseSchurComplementSolver::SparseSchurComplementSolver(
|
||
|
const LinearSolver::Options& options)
|
||
|
: SchurComplementSolver(options),
|
||
|
factor_(NULL),
|
||
|
cxsparse_factor_(NULL) {
|
||
|
}
|
||
|
|
||
|
SparseSchurComplementSolver::~SparseSchurComplementSolver() {
|
||
|
if (factor_ != NULL) {
|
||
|
ss_.Free(factor_);
|
||
|
factor_ = NULL;
|
||
|
}
|
||
|
|
||
|
if (cxsparse_factor_ != NULL) {
|
||
|
cxsparse_.Free(cxsparse_factor_);
|
||
|
cxsparse_factor_ = NULL;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
// Determine the non-zero blocks in the Schur Complement matrix, and
|
||
|
// initialize a BlockRandomAccessSparseMatrix object.
|
||
|
void SparseSchurComplementSolver::InitStorage(
|
||
|
const CompressedRowBlockStructure* bs) {
|
||
|
const int num_eliminate_blocks = options().elimination_groups[0];
|
||
|
const int num_col_blocks = bs->cols.size();
|
||
|
const int num_row_blocks = bs->rows.size();
|
||
|
|
||
|
blocks_.resize(num_col_blocks - num_eliminate_blocks, 0);
|
||
|
for (int i = num_eliminate_blocks; i < num_col_blocks; ++i) {
|
||
|
blocks_[i - num_eliminate_blocks] = bs->cols[i].size;
|
||
|
}
|
||
|
|
||
|
set<pair<int, int> > block_pairs;
|
||
|
for (int i = 0; i < blocks_.size(); ++i) {
|
||
|
block_pairs.insert(make_pair(i, i));
|
||
|
}
|
||
|
|
||
|
int r = 0;
|
||
|
while (r < num_row_blocks) {
|
||
|
int e_block_id = bs->rows[r].cells.front().block_id;
|
||
|
if (e_block_id >= num_eliminate_blocks) {
|
||
|
break;
|
||
|
}
|
||
|
vector<int> f_blocks;
|
||
|
|
||
|
// Add to the chunk until the first block in the row is
|
||
|
// different than the one in the first row for the chunk.
|
||
|
for (; r < num_row_blocks; ++r) {
|
||
|
const CompressedRow& row = bs->rows[r];
|
||
|
if (row.cells.front().block_id != e_block_id) {
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
// Iterate over the blocks in the row, ignoring the first
|
||
|
// block since it is the one to be eliminated.
|
||
|
for (int c = 1; c < row.cells.size(); ++c) {
|
||
|
const Cell& cell = row.cells[c];
|
||
|
f_blocks.push_back(cell.block_id - num_eliminate_blocks);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
sort(f_blocks.begin(), f_blocks.end());
|
||
|
f_blocks.erase(unique(f_blocks.begin(), f_blocks.end()), f_blocks.end());
|
||
|
for (int i = 0; i < f_blocks.size(); ++i) {
|
||
|
for (int j = i + 1; j < f_blocks.size(); ++j) {
|
||
|
block_pairs.insert(make_pair(f_blocks[i], f_blocks[j]));
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
// Remaing rows do not contribute to the chunks and directly go
|
||
|
// into the schur complement via an outer product.
|
||
|
for (; r < num_row_blocks; ++r) {
|
||
|
const CompressedRow& row = bs->rows[r];
|
||
|
CHECK_GE(row.cells.front().block_id, num_eliminate_blocks);
|
||
|
for (int i = 0; i < row.cells.size(); ++i) {
|
||
|
int r_block1_id = row.cells[i].block_id - num_eliminate_blocks;
|
||
|
for (int j = 0; j < row.cells.size(); ++j) {
|
||
|
int r_block2_id = row.cells[j].block_id - num_eliminate_blocks;
|
||
|
if (r_block1_id <= r_block2_id) {
|
||
|
block_pairs.insert(make_pair(r_block1_id, r_block2_id));
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
set_lhs(new BlockRandomAccessSparseMatrix(blocks_, block_pairs));
|
||
|
set_rhs(new double[lhs()->num_rows()]);
|
||
|
}
|
||
|
|
||
|
LinearSolver::Summary
|
||
|
SparseSchurComplementSolver::SolveReducedLinearSystem(
|
||
|
const LinearSolver::PerSolveOptions& per_solve_options,
|
||
|
double* solution) {
|
||
|
if (options().type == ITERATIVE_SCHUR) {
|
||
|
CHECK(options().use_explicit_schur_complement);
|
||
|
return SolveReducedLinearSystemUsingConjugateGradients(per_solve_options,
|
||
|
solution);
|
||
|
}
|
||
|
|
||
|
switch (options().sparse_linear_algebra_library_type) {
|
||
|
case SUITE_SPARSE:
|
||
|
return SolveReducedLinearSystemUsingSuiteSparse(per_solve_options,
|
||
|
solution);
|
||
|
case CX_SPARSE:
|
||
|
return SolveReducedLinearSystemUsingCXSparse(per_solve_options,
|
||
|
solution);
|
||
|
case EIGEN_SPARSE:
|
||
|
return SolveReducedLinearSystemUsingEigen(per_solve_options,
|
||
|
solution);
|
||
|
default:
|
||
|
LOG(FATAL) << "Unknown sparse linear algebra library : "
|
||
|
<< options().sparse_linear_algebra_library_type;
|
||
|
}
|
||
|
|
||
|
return LinearSolver::Summary();
|
||
|
}
|
||
|
|
||
|
// Solve the system Sx = r, assuming that the matrix S is stored in a
|
||
|
// BlockRandomAccessSparseMatrix. The linear system is solved using
|
||
|
// CHOLMOD's sparse cholesky factorization routines.
|
||
|
LinearSolver::Summary
|
||
|
SparseSchurComplementSolver::SolveReducedLinearSystemUsingSuiteSparse(
|
||
|
const LinearSolver::PerSolveOptions& per_solve_options,
|
||
|
double* solution) {
|
||
|
#ifdef CERES_NO_SUITESPARSE
|
||
|
|
||
|
LinearSolver::Summary summary;
|
||
|
summary.num_iterations = 0;
|
||
|
summary.termination_type = LINEAR_SOLVER_FATAL_ERROR;
|
||
|
summary.message = "Ceres was not built with SuiteSparse support. "
|
||
|
"Therefore, SPARSE_SCHUR cannot be used with SUITE_SPARSE";
|
||
|
return summary;
|
||
|
|
||
|
#else
|
||
|
|
||
|
LinearSolver::Summary summary;
|
||
|
summary.num_iterations = 0;
|
||
|
summary.termination_type = LINEAR_SOLVER_SUCCESS;
|
||
|
summary.message = "Success.";
|
||
|
|
||
|
TripletSparseMatrix* tsm =
|
||
|
const_cast<TripletSparseMatrix*>(
|
||
|
down_cast<const BlockRandomAccessSparseMatrix*>(lhs())->matrix());
|
||
|
const int num_rows = tsm->num_rows();
|
||
|
|
||
|
// The case where there are no f blocks, and the system is block
|
||
|
// diagonal.
|
||
|
if (num_rows == 0) {
|
||
|
return summary;
|
||
|
}
|
||
|
|
||
|
summary.num_iterations = 1;
|
||
|
cholmod_sparse* cholmod_lhs = NULL;
|
||
|
if (options().use_postordering) {
|
||
|
// If we are going to do a full symbolic analysis of the schur
|
||
|
// complement matrix from scratch and not rely on the
|
||
|
// pre-ordering, then the fastest path in cholmod_factorize is the
|
||
|
// one corresponding to upper triangular matrices.
|
||
|
|
||
|
// Create a upper triangular symmetric matrix.
|
||
|
cholmod_lhs = ss_.CreateSparseMatrix(tsm);
|
||
|
cholmod_lhs->stype = 1;
|
||
|
|
||
|
if (factor_ == NULL) {
|
||
|
factor_ = ss_.BlockAnalyzeCholesky(cholmod_lhs,
|
||
|
blocks_,
|
||
|
blocks_,
|
||
|
&summary.message);
|
||
|
}
|
||
|
} else {
|
||
|
// If we are going to use the natural ordering (i.e. rely on the
|
||
|
// pre-ordering computed by solver_impl.cc), then the fastest
|
||
|
// path in cholmod_factorize is the one corresponding to lower
|
||
|
// triangular matrices.
|
||
|
|
||
|
// Create a upper triangular symmetric matrix.
|
||
|
cholmod_lhs = ss_.CreateSparseMatrixTranspose(tsm);
|
||
|
cholmod_lhs->stype = -1;
|
||
|
|
||
|
if (factor_ == NULL) {
|
||
|
factor_ = ss_.AnalyzeCholeskyWithNaturalOrdering(cholmod_lhs,
|
||
|
&summary.message);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
if (factor_ == NULL) {
|
||
|
ss_.Free(cholmod_lhs);
|
||
|
summary.termination_type = LINEAR_SOLVER_FATAL_ERROR;
|
||
|
// No need to set message as it has already been set by the
|
||
|
// symbolic analysis routines above.
|
||
|
return summary;
|
||
|
}
|
||
|
|
||
|
summary.termination_type =
|
||
|
ss_.Cholesky(cholmod_lhs, factor_, &summary.message);
|
||
|
|
||
|
ss_.Free(cholmod_lhs);
|
||
|
|
||
|
if (summary.termination_type != LINEAR_SOLVER_SUCCESS) {
|
||
|
// No need to set message as it has already been set by the
|
||
|
// numeric factorization routine above.
|
||
|
return summary;
|
||
|
}
|
||
|
|
||
|
cholmod_dense* cholmod_rhs =
|
||
|
ss_.CreateDenseVector(const_cast<double*>(rhs()), num_rows, num_rows);
|
||
|
cholmod_dense* cholmod_solution = ss_.Solve(factor_,
|
||
|
cholmod_rhs,
|
||
|
&summary.message);
|
||
|
ss_.Free(cholmod_rhs);
|
||
|
|
||
|
if (cholmod_solution == NULL) {
|
||
|
summary.message =
|
||
|
"SuiteSparse failure. Unable to perform triangular solve.";
|
||
|
summary.termination_type = LINEAR_SOLVER_FAILURE;
|
||
|
return summary;
|
||
|
}
|
||
|
|
||
|
VectorRef(solution, num_rows)
|
||
|
= VectorRef(static_cast<double*>(cholmod_solution->x), num_rows);
|
||
|
ss_.Free(cholmod_solution);
|
||
|
return summary;
|
||
|
#endif // CERES_NO_SUITESPARSE
|
||
|
}
|
||
|
|
||
|
// Solve the system Sx = r, assuming that the matrix S is stored in a
|
||
|
// BlockRandomAccessSparseMatrix. The linear system is solved using
|
||
|
// CXSparse's sparse cholesky factorization routines.
|
||
|
LinearSolver::Summary
|
||
|
SparseSchurComplementSolver::SolveReducedLinearSystemUsingCXSparse(
|
||
|
const LinearSolver::PerSolveOptions& per_solve_options,
|
||
|
double* solution) {
|
||
|
#ifdef CERES_NO_CXSPARSE
|
||
|
|
||
|
LinearSolver::Summary summary;
|
||
|
summary.num_iterations = 0;
|
||
|
summary.termination_type = LINEAR_SOLVER_FATAL_ERROR;
|
||
|
summary.message = "Ceres was not built with CXSparse support. "
|
||
|
"Therefore, SPARSE_SCHUR cannot be used with CX_SPARSE";
|
||
|
return summary;
|
||
|
|
||
|
#else
|
||
|
|
||
|
LinearSolver::Summary summary;
|
||
|
summary.num_iterations = 0;
|
||
|
summary.termination_type = LINEAR_SOLVER_SUCCESS;
|
||
|
summary.message = "Success.";
|
||
|
|
||
|
// Extract the TripletSparseMatrix that is used for actually storing S.
|
||
|
TripletSparseMatrix* tsm =
|
||
|
const_cast<TripletSparseMatrix*>(
|
||
|
down_cast<const BlockRandomAccessSparseMatrix*>(lhs())->matrix());
|
||
|
const int num_rows = tsm->num_rows();
|
||
|
|
||
|
// The case where there are no f blocks, and the system is block
|
||
|
// diagonal.
|
||
|
if (num_rows == 0) {
|
||
|
return summary;
|
||
|
}
|
||
|
|
||
|
cs_di* lhs = CHECK_NOTNULL(cxsparse_.CreateSparseMatrix(tsm));
|
||
|
VectorRef(solution, num_rows) = ConstVectorRef(rhs(), num_rows);
|
||
|
|
||
|
// Compute symbolic factorization if not available.
|
||
|
if (cxsparse_factor_ == NULL) {
|
||
|
cxsparse_factor_ = cxsparse_.BlockAnalyzeCholesky(lhs, blocks_, blocks_);
|
||
|
}
|
||
|
|
||
|
if (cxsparse_factor_ == NULL) {
|
||
|
summary.termination_type = LINEAR_SOLVER_FATAL_ERROR;
|
||
|
summary.message =
|
||
|
"CXSparse failure. Unable to find symbolic factorization.";
|
||
|
} else if (!cxsparse_.SolveCholesky(lhs, cxsparse_factor_, solution)) {
|
||
|
summary.termination_type = LINEAR_SOLVER_FAILURE;
|
||
|
summary.message = "CXSparse::SolveCholesky failed.";
|
||
|
}
|
||
|
|
||
|
cxsparse_.Free(lhs);
|
||
|
return summary;
|
||
|
#endif // CERES_NO_CXPARSE
|
||
|
}
|
||
|
|
||
|
// Solve the system Sx = r, assuming that the matrix S is stored in a
|
||
|
// BlockRandomAccessSparseMatrix. The linear system is solved using
|
||
|
// Eigen's sparse cholesky factorization routines.
|
||
|
LinearSolver::Summary
|
||
|
SparseSchurComplementSolver::SolveReducedLinearSystemUsingEigen(
|
||
|
const LinearSolver::PerSolveOptions& per_solve_options,
|
||
|
double* solution) {
|
||
|
#ifndef CERES_USE_EIGEN_SPARSE
|
||
|
|
||
|
LinearSolver::Summary summary;
|
||
|
summary.num_iterations = 0;
|
||
|
summary.termination_type = LINEAR_SOLVER_FATAL_ERROR;
|
||
|
summary.message =
|
||
|
"SPARSE_SCHUR cannot be used with EIGEN_SPARSE. "
|
||
|
"Ceres was not built with support for "
|
||
|
"Eigen's SimplicialLDLT decomposition. "
|
||
|
"This requires enabling building with -DEIGENSPARSE=ON.";
|
||
|
return summary;
|
||
|
|
||
|
#else
|
||
|
EventLogger event_logger("SchurComplementSolver::EigenSolve");
|
||
|
LinearSolver::Summary summary;
|
||
|
summary.num_iterations = 0;
|
||
|
summary.termination_type = LINEAR_SOLVER_SUCCESS;
|
||
|
summary.message = "Success.";
|
||
|
|
||
|
// Extract the TripletSparseMatrix that is used for actually storing S.
|
||
|
TripletSparseMatrix* tsm =
|
||
|
const_cast<TripletSparseMatrix*>(
|
||
|
down_cast<const BlockRandomAccessSparseMatrix*>(lhs())->matrix());
|
||
|
const int num_rows = tsm->num_rows();
|
||
|
|
||
|
// The case where there are no f blocks, and the system is block
|
||
|
// diagonal.
|
||
|
if (num_rows == 0) {
|
||
|
return summary;
|
||
|
}
|
||
|
|
||
|
// This is an upper triangular matrix.
|
||
|
CompressedRowSparseMatrix crsm(*tsm);
|
||
|
// Map this to a column major, lower triangular matrix.
|
||
|
Eigen::MappedSparseMatrix<double, Eigen::ColMajor> eigen_lhs(
|
||
|
crsm.num_rows(),
|
||
|
crsm.num_rows(),
|
||
|
crsm.num_nonzeros(),
|
||
|
crsm.mutable_rows(),
|
||
|
crsm.mutable_cols(),
|
||
|
crsm.mutable_values());
|
||
|
event_logger.AddEvent("ToCompressedRowSparseMatrix");
|
||
|
|
||
|
// Compute symbolic factorization if one does not exist.
|
||
|
if (simplicial_ldlt_.get() == NULL) {
|
||
|
simplicial_ldlt_.reset(new SimplicialLDLT);
|
||
|
// This ordering is quite bad. The scalar ordering produced by the
|
||
|
// AMD algorithm is quite bad and can be an order of magnitude
|
||
|
// worse than the one computed using the block version of the
|
||
|
// algorithm.
|
||
|
simplicial_ldlt_->analyzePattern(eigen_lhs);
|
||
|
event_logger.AddEvent("Analysis");
|
||
|
if (simplicial_ldlt_->info() != Eigen::Success) {
|
||
|
summary.termination_type = LINEAR_SOLVER_FATAL_ERROR;
|
||
|
summary.message =
|
||
|
"Eigen failure. Unable to find symbolic factorization.";
|
||
|
return summary;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
simplicial_ldlt_->factorize(eigen_lhs);
|
||
|
event_logger.AddEvent("Factorize");
|
||
|
if (simplicial_ldlt_->info() != Eigen::Success) {
|
||
|
summary.termination_type = LINEAR_SOLVER_FAILURE;
|
||
|
summary.message = "Eigen failure. Unable to find numeric factoriztion.";
|
||
|
return summary;
|
||
|
}
|
||
|
|
||
|
VectorRef(solution, num_rows) =
|
||
|
simplicial_ldlt_->solve(ConstVectorRef(rhs(), num_rows));
|
||
|
event_logger.AddEvent("Solve");
|
||
|
if (simplicial_ldlt_->info() != Eigen::Success) {
|
||
|
summary.termination_type = LINEAR_SOLVER_FAILURE;
|
||
|
summary.message = "Eigen failure. Unable to do triangular solve.";
|
||
|
}
|
||
|
|
||
|
return summary;
|
||
|
#endif // CERES_USE_EIGEN_SPARSE
|
||
|
}
|
||
|
|
||
|
LinearSolver::Summary
|
||
|
SparseSchurComplementSolver::SolveReducedLinearSystemUsingConjugateGradients(
|
||
|
const LinearSolver::PerSolveOptions& per_solve_options,
|
||
|
double* solution) {
|
||
|
const int num_rows = lhs()->num_rows();
|
||
|
// The case where there are no f blocks, and the system is block
|
||
|
// diagonal.
|
||
|
if (num_rows == 0) {
|
||
|
LinearSolver::Summary summary;
|
||
|
summary.num_iterations = 0;
|
||
|
summary.termination_type = LINEAR_SOLVER_SUCCESS;
|
||
|
summary.message = "Success.";
|
||
|
return summary;
|
||
|
}
|
||
|
|
||
|
// Only SCHUR_JACOBI is supported over here right now.
|
||
|
CHECK_EQ(options().preconditioner_type, SCHUR_JACOBI);
|
||
|
|
||
|
if (preconditioner_.get() == NULL) {
|
||
|
preconditioner_.reset(new BlockRandomAccessDiagonalMatrix(blocks_));
|
||
|
}
|
||
|
|
||
|
BlockRandomAccessSparseMatrix* sc =
|
||
|
down_cast<BlockRandomAccessSparseMatrix*>(
|
||
|
const_cast<BlockRandomAccessMatrix*>(lhs()));
|
||
|
|
||
|
// Extract block diagonal from the Schur complement to construct the
|
||
|
// schur_jacobi preconditioner.
|
||
|
for (int i = 0; i < blocks_.size(); ++i) {
|
||
|
const int block_size = blocks_[i];
|
||
|
|
||
|
int sc_r, sc_c, sc_row_stride, sc_col_stride;
|
||
|
CellInfo* sc_cell_info =
|
||
|
CHECK_NOTNULL(sc->GetCell(i, i,
|
||
|
&sc_r, &sc_c,
|
||
|
&sc_row_stride, &sc_col_stride));
|
||
|
MatrixRef sc_m(sc_cell_info->values, sc_row_stride, sc_col_stride);
|
||
|
|
||
|
int pre_r, pre_c, pre_row_stride, pre_col_stride;
|
||
|
CellInfo* pre_cell_info = CHECK_NOTNULL(
|
||
|
preconditioner_->GetCell(i, i,
|
||
|
&pre_r, &pre_c,
|
||
|
&pre_row_stride, &pre_col_stride));
|
||
|
MatrixRef pre_m(pre_cell_info->values, pre_row_stride, pre_col_stride);
|
||
|
|
||
|
pre_m.block(pre_r, pre_c, block_size, block_size) =
|
||
|
sc_m.block(sc_r, sc_c, block_size, block_size);
|
||
|
}
|
||
|
preconditioner_->Invert();
|
||
|
|
||
|
VectorRef(solution, num_rows).setZero();
|
||
|
|
||
|
scoped_ptr<LinearOperator> lhs_adapter(
|
||
|
new BlockRandomAccessSparseMatrixAdapter(*sc));
|
||
|
scoped_ptr<LinearOperator> preconditioner_adapter(
|
||
|
new BlockRandomAccessDiagonalMatrixAdapter(*preconditioner_));
|
||
|
|
||
|
|
||
|
LinearSolver::Options cg_options;
|
||
|
cg_options.min_num_iterations = options().min_num_iterations;
|
||
|
cg_options.max_num_iterations = options().max_num_iterations;
|
||
|
ConjugateGradientsSolver cg_solver(cg_options);
|
||
|
|
||
|
LinearSolver::PerSolveOptions cg_per_solve_options;
|
||
|
cg_per_solve_options.r_tolerance = per_solve_options.r_tolerance;
|
||
|
cg_per_solve_options.q_tolerance = per_solve_options.q_tolerance;
|
||
|
cg_per_solve_options.preconditioner = preconditioner_adapter.get();
|
||
|
|
||
|
return cg_solver.Solve(lhs_adapter.get(),
|
||
|
rhs(),
|
||
|
cg_per_solve_options,
|
||
|
solution);
|
||
|
}
|
||
|
|
||
|
} // namespace internal
|
||
|
} // namespace ceres
|