| // Ceres Solver - A fast non-linear least squares minimizer |
| // Copyright 2022 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/block_random_access_sparse_matrix.h" |
| |
| #include <algorithm> |
| #include <memory> |
| #include <set> |
| #include <utility> |
| #include <vector> |
| |
| #include "ceres/internal/export.h" |
| #include "ceres/parallel_for.h" |
| #include "ceres/triplet_sparse_matrix.h" |
| #include "ceres/types.h" |
| #include "glog/logging.h" |
| |
| namespace ceres::internal { |
| |
| BlockRandomAccessSparseMatrix::BlockRandomAccessSparseMatrix( |
| const std::vector<Block>& blocks, |
| const std::set<std::pair<int, int>>& block_pairs, |
| ContextImpl* context, |
| int num_threads) |
| : kMaxRowBlocks(10 * 1000 * 1000), |
| blocks_(blocks), |
| context_(context), |
| num_threads_(num_threads) { |
| CHECK_LT(blocks.size(), kMaxRowBlocks); |
| |
| const int num_cols = NumScalarEntries(blocks); |
| |
| // Count the number of scalar non-zero entries and build the layout |
| // object for looking into the values array of the |
| // TripletSparseMatrix. |
| int num_nonzeros = 0; |
| for (const auto& block_pair : block_pairs) { |
| const int row_block_size = blocks_[block_pair.first].size; |
| const int col_block_size = blocks_[block_pair.second].size; |
| num_nonzeros += row_block_size * col_block_size; |
| } |
| |
| VLOG(1) << "Matrix Size [" << num_cols << "," << num_cols << "] " |
| << num_nonzeros; |
| |
| tsm_ = |
| std::make_unique<TripletSparseMatrix>(num_cols, num_cols, num_nonzeros); |
| tsm_->set_num_nonzeros(num_nonzeros); |
| int* rows = tsm_->mutable_rows(); |
| int* cols = tsm_->mutable_cols(); |
| double* values = tsm_->mutable_values(); |
| |
| int pos = 0; |
| for (const auto& block_pair : block_pairs) { |
| const int row_block_size = blocks_[block_pair.first].size; |
| const int col_block_size = blocks_[block_pair.second].size; |
| cell_values_.emplace_back(block_pair, values + pos); |
| layout_[IntPairToLong(block_pair.first, block_pair.second)] = |
| std::make_unique<CellInfo>(values + pos); |
| pos += row_block_size * col_block_size; |
| } |
| |
| // Fill the sparsity pattern of the underlying matrix. |
| for (const auto& block_pair : block_pairs) { |
| const int row_block_id = block_pair.first; |
| const int col_block_id = block_pair.second; |
| const int row_block_size = blocks_[row_block_id].size; |
| const int col_block_size = blocks_[col_block_id].size; |
| int pos = |
| layout_[IntPairToLong(row_block_id, col_block_id)]->values - values; |
| for (int r = 0; r < row_block_size; ++r) { |
| for (int c = 0; c < col_block_size; ++c, ++pos) { |
| rows[pos] = blocks_[row_block_id].position + r; |
| cols[pos] = blocks_[col_block_id].position + c; |
| values[pos] = 1.0; |
| DCHECK_LT(rows[pos], tsm_->num_rows()); |
| DCHECK_LT(cols[pos], tsm_->num_rows()); |
| } |
| } |
| } |
| } |
| |
| CellInfo* BlockRandomAccessSparseMatrix::GetCell(int row_block_id, |
| int col_block_id, |
| int* row, |
| int* col, |
| int* row_stride, |
| int* col_stride) { |
| const auto it = layout_.find(IntPairToLong(row_block_id, col_block_id)); |
| if (it == layout_.end()) { |
| return nullptr; |
| } |
| |
| // Each cell is stored contiguously as its own little dense matrix. |
| *row = 0; |
| *col = 0; |
| *row_stride = blocks_[row_block_id].size; |
| *col_stride = blocks_[col_block_id].size; |
| return it->second.get(); |
| } |
| |
| // Assume that the user does not hold any locks on any cell blocks |
| // when they are calling SetZero. |
| void BlockRandomAccessSparseMatrix::SetZero() { |
| ParallelSetZero( |
| context_, num_threads_, tsm_->mutable_values(), tsm_->num_nonzeros()); |
| } |
| |
| void BlockRandomAccessSparseMatrix::SymmetricRightMultiplyAndAccumulate( |
| const double* x, double* y) const { |
| for (const auto& cell_position_and_data : cell_values_) { |
| const int row = cell_position_and_data.first.first; |
| const int row_block_size = blocks_[row].size; |
| const int row_block_pos = blocks_[row].position; |
| |
| const int col = cell_position_and_data.first.second; |
| const int col_block_size = blocks_[col].size; |
| const int col_block_pos = blocks_[col].position; |
| |
| MatrixVectorMultiply<Eigen::Dynamic, Eigen::Dynamic, 1>( |
| cell_position_and_data.second, |
| row_block_size, |
| col_block_size, |
| x + col_block_pos, |
| y + row_block_pos); |
| |
| // Since the matrix is symmetric, but only the upper triangular |
| // part is stored, if the block being accessed is not a diagonal |
| // block, then use the same block to do the corresponding lower |
| // triangular multiply also. |
| if (row != col) { |
| MatrixTransposeVectorMultiply<Eigen::Dynamic, Eigen::Dynamic, 1>( |
| cell_position_and_data.second, |
| row_block_size, |
| col_block_size, |
| x + row_block_pos, |
| y + col_block_pos); |
| } |
| } |
| } |
| |
| } // namespace ceres::internal |