Add BlockRandomAccessDiagonalMatrix.
This class is used in the SchurJacobiPreconditioner for
storing the preconditioner matrix. Using it speeds up
the computation of the preconditioner by ~15% due to
the elimination of a hash table lookup.
Change-Id: Iba2b34aad0d9eb9bcb7f6e6fad16aa416aac0d2a
diff --git a/internal/ceres/block_random_access_diagonal_matrix_test.cc b/internal/ceres/block_random_access_diagonal_matrix_test.cc
new file mode 100644
index 0000000..e19268b
--- /dev/null
+++ b/internal/ceres/block_random_access_diagonal_matrix_test.cc
@@ -0,0 +1,116 @@
+// Ceres Solver - A fast non-linear least squares minimizer
+// Copyright 2013 Google Inc. All rights reserved.
+// http://code.google.com/p/ceres-solver/
+//
+// 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 <limits>
+#include <vector>
+
+#include "ceres/block_random_access_diagonal_matrix.h"
+#include "ceres/internal/eigen.h"
+#include "glog/logging.h"
+#include "gtest/gtest.h"
+
+namespace ceres {
+namespace internal {
+
+TEST(BlockRandomAccessDiagonalMatrix, GetCell) {
+ vector<int> blocks;
+ blocks.push_back(3);
+ blocks.push_back(4);
+ blocks.push_back(5);
+ const int num_rows = 3 + 4 + 5;
+ const int num_nonzeros = 3 * 3 + 4 * 4 + 5 * 5;
+
+ BlockRandomAccessDiagonalMatrix m(blocks);
+ EXPECT_EQ(m.num_rows(), num_rows);
+ EXPECT_EQ(m.num_cols(), num_rows);
+
+ for (int i = 0; i < blocks.size(); ++i) {
+ const int row_block_id = i;
+ int col_block_id;
+ int row;
+ int col;
+ int row_stride;
+ int col_stride;
+
+ for (int j = 0; j < blocks.size(); ++j) {
+ col_block_id = j;
+ CellInfo* cell = m.GetCell(row_block_id, col_block_id,
+ &row, &col,
+ &row_stride, &col_stride);
+ // Off diagonal entries are not present.
+ if (i != j) {
+ EXPECT_TRUE(cell == NULL);
+ continue;
+ }
+
+ EXPECT_TRUE(cell != NULL);
+ EXPECT_EQ(row, 0);
+ EXPECT_EQ(col, 0);
+ EXPECT_EQ(row_stride, blocks[row_block_id]);
+ EXPECT_EQ(col_stride, blocks[col_block_id]);
+
+ // Write into the block
+ MatrixRef(cell->values, row_stride, col_stride).block(
+ row, col, blocks[row_block_id], blocks[col_block_id]) =
+ (row_block_id + 1) * (col_block_id +1) *
+ Matrix::Ones(blocks[row_block_id], blocks[col_block_id]);
+ }
+ }
+
+ const TripletSparseMatrix* tsm = m.matrix();
+ EXPECT_EQ(tsm->num_nonzeros(), num_nonzeros);
+ EXPECT_EQ(tsm->max_num_nonzeros(), num_nonzeros);
+
+ Matrix dense;
+ tsm->ToDenseMatrix(&dense);
+
+ double kTolerance = 1e-14;
+
+ // (0,0)
+ EXPECT_NEAR((dense.block(0, 0, 3, 3) - Matrix::Ones(3, 3)).norm(),
+ 0.0,
+ kTolerance);
+
+ // (1,1)
+ EXPECT_NEAR((dense.block(3, 3, 4, 4) - 2 * 2 * Matrix::Ones(4, 4)).norm(),
+ 0.0,
+ kTolerance);
+
+ // (1,1)
+ EXPECT_NEAR((dense.block(7, 7, 5, 5) - 3 * 3 * Matrix::Ones(5, 5)).norm(),
+ 0.0,
+ kTolerance);
+
+ // There is nothing else in the matrix besides these four blocks.
+ EXPECT_NEAR(dense.norm(), sqrt(9.0 + 16. * 16. + 81.0 * 25.), kTolerance);
+}
+
+} // namespace internal
+} // namespace ceres
