Squashed 'third_party/ceres/' content from commit e51e9b4

Change-Id: I763587619d57e594d3fa158dc3a7fe0b89a1743b
git-subtree-dir: third_party/ceres
git-subtree-split: e51e9b46f6ca88ab8b2266d0e362771db6d98067
diff --git a/internal/ceres/block_sparse_matrix.cc b/internal/ceres/block_sparse_matrix.cc
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+// 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/block_sparse_matrix.h"
+
+#include <cstddef>
+#include <algorithm>
+#include <vector>
+#include "ceres/block_structure.h"
+#include "ceres/internal/eigen.h"
+#include "ceres/random.h"
+#include "ceres/small_blas.h"
+#include "ceres/triplet_sparse_matrix.h"
+#include "glog/logging.h"
+
+namespace ceres {
+namespace internal {
+
+using std::vector;
+
+BlockSparseMatrix::~BlockSparseMatrix() {}
+
+BlockSparseMatrix::BlockSparseMatrix(
+    CompressedRowBlockStructure* block_structure)
+    : num_rows_(0),
+      num_cols_(0),
+      num_nonzeros_(0),
+      block_structure_(block_structure) {
+  CHECK(block_structure_ != nullptr);
+
+  // Count the number of columns in the matrix.
+  for (int i = 0; i < block_structure_->cols.size(); ++i) {
+    num_cols_ += block_structure_->cols[i].size;
+  }
+
+  // Count the number of non-zero entries and the number of rows in
+  // the matrix.
+  for (int i = 0; i < block_structure_->rows.size(); ++i) {
+    int row_block_size = block_structure_->rows[i].block.size;
+    num_rows_ += row_block_size;
+
+    const vector<Cell>& cells = block_structure_->rows[i].cells;
+    for (int j = 0; j < cells.size(); ++j) {
+      int col_block_id = cells[j].block_id;
+      int col_block_size = block_structure_->cols[col_block_id].size;
+      num_nonzeros_ += col_block_size * row_block_size;
+    }
+  }
+
+  CHECK_GE(num_rows_, 0);
+  CHECK_GE(num_cols_, 0);
+  CHECK_GE(num_nonzeros_, 0);
+  VLOG(2) << "Allocating values array with "
+          << num_nonzeros_ * sizeof(double) << " bytes.";  // NOLINT
+  values_.reset(new double[num_nonzeros_]);
+  max_num_nonzeros_ = num_nonzeros_;
+  CHECK(values_ != nullptr);
+}
+
+void BlockSparseMatrix::SetZero() {
+  std::fill(values_.get(), values_.get() + num_nonzeros_, 0.0);
+}
+
+void BlockSparseMatrix::RightMultiply(const double* x,  double* y) const {
+  CHECK(x != nullptr);
+  CHECK(y != nullptr);
+
+  for (int i = 0; i < block_structure_->rows.size(); ++i) {
+    int row_block_pos = block_structure_->rows[i].block.position;
+    int row_block_size = block_structure_->rows[i].block.size;
+    const vector<Cell>& cells = block_structure_->rows[i].cells;
+    for (int j = 0; j < cells.size(); ++j) {
+      int col_block_id = cells[j].block_id;
+      int col_block_size = block_structure_->cols[col_block_id].size;
+      int col_block_pos = block_structure_->cols[col_block_id].position;
+      MatrixVectorMultiply<Eigen::Dynamic, Eigen::Dynamic, 1>(
+          values_.get() + cells[j].position, row_block_size, col_block_size,
+          x + col_block_pos,
+          y + row_block_pos);
+    }
+  }
+}
+
+void BlockSparseMatrix::LeftMultiply(const double* x, double* y) const {
+  CHECK(x != nullptr);
+  CHECK(y != nullptr);
+
+  for (int i = 0; i < block_structure_->rows.size(); ++i) {
+    int row_block_pos = block_structure_->rows[i].block.position;
+    int row_block_size = block_structure_->rows[i].block.size;
+    const vector<Cell>& cells = block_structure_->rows[i].cells;
+    for (int j = 0; j < cells.size(); ++j) {
+      int col_block_id = cells[j].block_id;
+      int col_block_size = block_structure_->cols[col_block_id].size;
+      int col_block_pos = block_structure_->cols[col_block_id].position;
+      MatrixTransposeVectorMultiply<Eigen::Dynamic, Eigen::Dynamic, 1>(
+          values_.get() + cells[j].position, row_block_size, col_block_size,
+          x + row_block_pos,
+          y + col_block_pos);
+    }
+  }
+}
+
+void BlockSparseMatrix::SquaredColumnNorm(double* x) const {
+  CHECK(x != nullptr);
+  VectorRef(x, num_cols_).setZero();
+  for (int i = 0; i < block_structure_->rows.size(); ++i) {
+    int row_block_size = block_structure_->rows[i].block.size;
+    const vector<Cell>& cells = block_structure_->rows[i].cells;
+    for (int j = 0; j < cells.size(); ++j) {
+      int col_block_id = cells[j].block_id;
+      int col_block_size = block_structure_->cols[col_block_id].size;
+      int col_block_pos = block_structure_->cols[col_block_id].position;
+      const MatrixRef m(values_.get() + cells[j].position,
+                        row_block_size, col_block_size);
+      VectorRef(x + col_block_pos, col_block_size) += m.colwise().squaredNorm();
+    }
+  }
+}
+
+void BlockSparseMatrix::ScaleColumns(const double* scale) {
+  CHECK(scale != nullptr);
+
+  for (int i = 0; i < block_structure_->rows.size(); ++i) {
+    int row_block_size = block_structure_->rows[i].block.size;
+    const vector<Cell>& cells = block_structure_->rows[i].cells;
+    for (int j = 0; j < cells.size(); ++j) {
+      int col_block_id = cells[j].block_id;
+      int col_block_size = block_structure_->cols[col_block_id].size;
+      int col_block_pos = block_structure_->cols[col_block_id].position;
+      MatrixRef m(values_.get() + cells[j].position,
+                        row_block_size, col_block_size);
+      m *= ConstVectorRef(scale + col_block_pos, col_block_size).asDiagonal();
+    }
+  }
+}
+
+void BlockSparseMatrix::ToDenseMatrix(Matrix* dense_matrix) const {
+  CHECK(dense_matrix != nullptr);
+
+  dense_matrix->resize(num_rows_, num_cols_);
+  dense_matrix->setZero();
+  Matrix& m = *dense_matrix;
+
+  for (int i = 0; i < block_structure_->rows.size(); ++i) {
+    int row_block_pos = block_structure_->rows[i].block.position;
+    int row_block_size = block_structure_->rows[i].block.size;
+    const vector<Cell>& cells = block_structure_->rows[i].cells;
+    for (int j = 0; j < cells.size(); ++j) {
+      int col_block_id = cells[j].block_id;
+      int col_block_size = block_structure_->cols[col_block_id].size;
+      int col_block_pos = block_structure_->cols[col_block_id].position;
+      int jac_pos = cells[j].position;
+      m.block(row_block_pos, col_block_pos, row_block_size, col_block_size)
+          += MatrixRef(values_.get() + jac_pos, row_block_size, col_block_size);
+    }
+  }
+}
+
+void BlockSparseMatrix::ToTripletSparseMatrix(
+    TripletSparseMatrix* matrix) const {
+  CHECK(matrix != nullptr);
+
+  matrix->Reserve(num_nonzeros_);
+  matrix->Resize(num_rows_, num_cols_);
+  matrix->SetZero();
+
+  for (int i = 0; i < block_structure_->rows.size(); ++i) {
+    int row_block_pos = block_structure_->rows[i].block.position;
+    int row_block_size = block_structure_->rows[i].block.size;
+    const vector<Cell>& cells = block_structure_->rows[i].cells;
+    for (int j = 0; j < cells.size(); ++j) {
+      int col_block_id = cells[j].block_id;
+      int col_block_size = block_structure_->cols[col_block_id].size;
+      int col_block_pos = block_structure_->cols[col_block_id].position;
+      int jac_pos = cells[j].position;
+       for (int r = 0; r < row_block_size; ++r) {
+        for (int c = 0; c < col_block_size; ++c, ++jac_pos) {
+          matrix->mutable_rows()[jac_pos] = row_block_pos + r;
+          matrix->mutable_cols()[jac_pos] = col_block_pos + c;
+          matrix->mutable_values()[jac_pos] = values_[jac_pos];
+        }
+      }
+    }
+  }
+  matrix->set_num_nonzeros(num_nonzeros_);
+}
+
+// Return a pointer to the block structure. We continue to hold
+// ownership of the object though.
+const CompressedRowBlockStructure* BlockSparseMatrix::block_structure()
+    const {
+  return block_structure_.get();
+}
+
+void BlockSparseMatrix::ToTextFile(FILE* file) const {
+  CHECK(file != nullptr);
+  for (int i = 0; i < block_structure_->rows.size(); ++i) {
+    const int row_block_pos = block_structure_->rows[i].block.position;
+    const int row_block_size = block_structure_->rows[i].block.size;
+    const vector<Cell>& cells = block_structure_->rows[i].cells;
+    for (int j = 0; j < cells.size(); ++j) {
+      const int col_block_id = cells[j].block_id;
+      const int col_block_size = block_structure_->cols[col_block_id].size;
+      const int col_block_pos = block_structure_->cols[col_block_id].position;
+      int jac_pos = cells[j].position;
+      for (int r = 0; r < row_block_size; ++r) {
+        for (int c = 0; c < col_block_size; ++c) {
+          fprintf(file, "% 10d % 10d %17f\n",
+                  row_block_pos + r,
+                  col_block_pos + c,
+                  values_[jac_pos++]);
+        }
+      }
+    }
+  }
+}
+
+BlockSparseMatrix* BlockSparseMatrix::CreateDiagonalMatrix(
+    const double* diagonal, const std::vector<Block>& column_blocks) {
+  // Create the block structure for the diagonal matrix.
+  CompressedRowBlockStructure* bs = new CompressedRowBlockStructure();
+  bs->cols = column_blocks;
+  int position = 0;
+  bs->rows.resize(column_blocks.size(), CompressedRow(1));
+  for (int i = 0; i < column_blocks.size(); ++i) {
+    CompressedRow& row = bs->rows[i];
+    row.block = column_blocks[i];
+    Cell& cell = row.cells[0];
+    cell.block_id = i;
+    cell.position = position;
+    position += row.block.size * row.block.size;
+  }
+
+  // Create the BlockSparseMatrix with the given block structure.
+  BlockSparseMatrix* matrix = new BlockSparseMatrix(bs);
+  matrix->SetZero();
+
+  // Fill the values array of the block sparse matrix.
+  double* values = matrix->mutable_values();
+  for (int i = 0; i < column_blocks.size(); ++i) {
+    const int size = column_blocks[i].size;
+    for (int j = 0; j < size; ++j) {
+      // (j + 1) * size is compact way of accessing the (j,j) entry.
+      values[j * (size + 1)] = diagonal[j];
+    }
+    diagonal += size;
+    values += size * size;
+  }
+
+  return matrix;
+}
+
+void BlockSparseMatrix::AppendRows(const BlockSparseMatrix& m) {
+  CHECK_EQ(m.num_cols(), num_cols());
+  const CompressedRowBlockStructure* m_bs = m.block_structure();
+  CHECK_EQ(m_bs->cols.size(), block_structure_->cols.size());
+
+  const int old_num_nonzeros = num_nonzeros_;
+  const int old_num_row_blocks = block_structure_->rows.size();
+  block_structure_->rows.resize(old_num_row_blocks + m_bs->rows.size());
+
+  for (int i = 0; i < m_bs->rows.size(); ++i) {
+    const CompressedRow& m_row = m_bs->rows[i];
+    CompressedRow& row = block_structure_->rows[old_num_row_blocks + i];
+    row.block.size = m_row.block.size;
+    row.block.position = num_rows_;
+    num_rows_ += m_row.block.size;
+    row.cells.resize(m_row.cells.size());
+    for (int c = 0; c < m_row.cells.size(); ++c) {
+      const int block_id = m_row.cells[c].block_id;
+      row.cells[c].block_id = block_id;
+      row.cells[c].position = num_nonzeros_;
+      num_nonzeros_ += m_row.block.size * m_bs->cols[block_id].size;
+    }
+  }
+
+  if (num_nonzeros_ > max_num_nonzeros_) {
+    double* new_values = new double[num_nonzeros_];
+    std::copy(values_.get(), values_.get() + old_num_nonzeros, new_values);
+    values_.reset(new_values);
+    max_num_nonzeros_ = num_nonzeros_;
+  }
+
+  std::copy(m.values(),
+            m.values() + m.num_nonzeros(),
+            values_.get() + old_num_nonzeros);
+}
+
+void BlockSparseMatrix::DeleteRowBlocks(const int delta_row_blocks) {
+  const int num_row_blocks = block_structure_->rows.size();
+  int delta_num_nonzeros = 0;
+  int delta_num_rows = 0;
+  const std::vector<Block>& column_blocks = block_structure_->cols;
+  for (int i = 0; i < delta_row_blocks; ++i) {
+    const CompressedRow& row = block_structure_->rows[num_row_blocks - i - 1];
+    delta_num_rows += row.block.size;
+    for (int c = 0; c < row.cells.size(); ++c) {
+      const Cell& cell = row.cells[c];
+      delta_num_nonzeros += row.block.size * column_blocks[cell.block_id].size;
+    }
+  }
+  num_nonzeros_ -= delta_num_nonzeros;
+  num_rows_ -= delta_num_rows;
+  block_structure_->rows.resize(num_row_blocks - delta_row_blocks);
+}
+
+BlockSparseMatrix* BlockSparseMatrix::CreateRandomMatrix(
+    const BlockSparseMatrix::RandomMatrixOptions& options) {
+  CHECK_GT(options.num_row_blocks, 0);
+  CHECK_GT(options.min_row_block_size, 0);
+  CHECK_GT(options.max_row_block_size, 0);
+  CHECK_LE(options.min_row_block_size, options.max_row_block_size);
+  CHECK_GT(options.block_density, 0.0);
+  CHECK_LE(options.block_density, 1.0);
+
+  CompressedRowBlockStructure* bs = new CompressedRowBlockStructure();
+  if (options.col_blocks.empty()) {
+    CHECK_GT(options.num_col_blocks, 0);
+    CHECK_GT(options.min_col_block_size, 0);
+    CHECK_GT(options.max_col_block_size, 0);
+    CHECK_LE(options.min_col_block_size, options.max_col_block_size);
+
+    // Generate the col block structure.
+    int col_block_position = 0;
+    for (int i = 0; i < options.num_col_blocks; ++i) {
+      // Generate a random integer in [min_col_block_size, max_col_block_size]
+      const int delta_block_size =
+          Uniform(options.max_col_block_size - options.min_col_block_size);
+      const int col_block_size = options.min_col_block_size + delta_block_size;
+      bs->cols.push_back(Block(col_block_size, col_block_position));
+      col_block_position += col_block_size;
+    }
+  } else {
+    bs->cols = options.col_blocks;
+  }
+
+  bool matrix_has_blocks = false;
+  while (!matrix_has_blocks) {
+    VLOG(1) << "Clearing";
+    bs->rows.clear();
+    int row_block_position = 0;
+    int value_position = 0;
+    for (int r = 0; r < options.num_row_blocks; ++r) {
+
+      const int delta_block_size =
+          Uniform(options.max_row_block_size - options.min_row_block_size);
+      const int row_block_size = options.min_row_block_size + delta_block_size;
+      bs->rows.push_back(CompressedRow());
+      CompressedRow& row = bs->rows.back();
+      row.block.size = row_block_size;
+      row.block.position = row_block_position;
+      row_block_position += row_block_size;
+      for (int c = 0; c < bs->cols.size(); ++c) {
+        if (RandDouble() > options.block_density) continue;
+
+        row.cells.push_back(Cell());
+        Cell& cell = row.cells.back();
+        cell.block_id = c;
+        cell.position = value_position;
+        value_position += row_block_size * bs->cols[c].size;
+        matrix_has_blocks = true;
+      }
+    }
+  }
+
+  BlockSparseMatrix* matrix = new BlockSparseMatrix(bs);
+  double* values = matrix->mutable_values();
+  for (int i = 0; i < matrix->num_nonzeros(); ++i) {
+    values[i] = RandNormal();
+  }
+
+  return matrix;
+}
+
+}  // namespace internal
+}  // namespace ceres