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Diffstat (limited to 'extern/libmv/third_party/ceres/internal/ceres/incomplete_lq_factorization.cc')
-rw-r--r-- | extern/libmv/third_party/ceres/internal/ceres/incomplete_lq_factorization.cc | 239 |
1 files changed, 0 insertions, 239 deletions
diff --git a/extern/libmv/third_party/ceres/internal/ceres/incomplete_lq_factorization.cc b/extern/libmv/third_party/ceres/internal/ceres/incomplete_lq_factorization.cc deleted file mode 100644 index 6ba38ec8eec..00000000000 --- a/extern/libmv/third_party/ceres/internal/ceres/incomplete_lq_factorization.cc +++ /dev/null @@ -1,239 +0,0 @@ -// 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 "ceres/incomplete_lq_factorization.h" - -#include <vector> -#include <utility> -#include <cmath> -#include "ceres/compressed_row_sparse_matrix.h" -#include "ceres/internal/eigen.h" -#include "ceres/internal/port.h" -#include "glog/logging.h" - -namespace ceres { -namespace internal { - -// Normalize a row and return it's norm. -inline double NormalizeRow(const int row, CompressedRowSparseMatrix* matrix) { - const int row_begin = matrix->rows()[row]; - const int row_end = matrix->rows()[row + 1]; - - double* values = matrix->mutable_values(); - double norm = 0.0; - for (int i = row_begin; i < row_end; ++i) { - norm += values[i] * values[i]; - } - - norm = sqrt(norm); - const double inverse_norm = 1.0 / norm; - for (int i = row_begin; i < row_end; ++i) { - values[i] *= inverse_norm; - } - - return norm; -} - -// Compute a(row_a,:) * b(row_b, :)' -inline double RowDotProduct(const CompressedRowSparseMatrix& a, - const int row_a, - const CompressedRowSparseMatrix& b, - const int row_b) { - const int* a_rows = a.rows(); - const int* a_cols = a.cols(); - const double* a_values = a.values(); - - const int* b_rows = b.rows(); - const int* b_cols = b.cols(); - const double* b_values = b.values(); - - const int row_a_end = a_rows[row_a + 1]; - const int row_b_end = b_rows[row_b + 1]; - - int idx_a = a_rows[row_a]; - int idx_b = b_rows[row_b]; - double dot_product = 0.0; - while (idx_a < row_a_end && idx_b < row_b_end) { - if (a_cols[idx_a] == b_cols[idx_b]) { - dot_product += a_values[idx_a++] * b_values[idx_b++]; - } - - while (a_cols[idx_a] < b_cols[idx_b] && idx_a < row_a_end) { - ++idx_a; - } - - while (a_cols[idx_a] > b_cols[idx_b] && idx_b < row_b_end) { - ++idx_b; - } - } - - return dot_product; -} - -struct SecondGreaterThan { - public: - bool operator()(const pair<int, double>& lhs, - const pair<int, double>& rhs) const { - return (fabs(lhs.second) > fabs(rhs.second)); - } -}; - -// In the row vector dense_row(0:num_cols), drop values smaller than -// the max_value * drop_tolerance. Of the remaining non-zero values, -// choose at most level_of_fill values and then add the resulting row -// vector to matrix. - -void DropEntriesAndAddRow(const Vector& dense_row, - const int num_entries, - const int level_of_fill, - const double drop_tolerance, - vector<pair<int, double> >* scratch, - CompressedRowSparseMatrix* matrix) { - int* rows = matrix->mutable_rows(); - int* cols = matrix->mutable_cols(); - double* values = matrix->mutable_values(); - int num_nonzeros = rows[matrix->num_rows()]; - - if (num_entries == 0) { - matrix->set_num_rows(matrix->num_rows() + 1); - rows[matrix->num_rows()] = num_nonzeros; - return; - } - - const double max_value = dense_row.head(num_entries).cwiseAbs().maxCoeff(); - const double threshold = drop_tolerance * max_value; - - int scratch_count = 0; - for (int i = 0; i < num_entries; ++i) { - if (fabs(dense_row[i]) > threshold) { - pair<int, double>& entry = (*scratch)[scratch_count]; - entry.first = i; - entry.second = dense_row[i]; - ++scratch_count; - } - } - - if (scratch_count > level_of_fill) { - nth_element(scratch->begin(), - scratch->begin() + level_of_fill, - scratch->begin() + scratch_count, - SecondGreaterThan()); - scratch_count = level_of_fill; - sort(scratch->begin(), scratch->begin() + scratch_count); - } - - for (int i = 0; i < scratch_count; ++i) { - const pair<int, double>& entry = (*scratch)[i]; - cols[num_nonzeros] = entry.first; - values[num_nonzeros] = entry.second; - ++num_nonzeros; - } - - matrix->set_num_rows(matrix->num_rows() + 1); - rows[matrix->num_rows()] = num_nonzeros; -} - -// Saad's Incomplete LQ factorization algorithm. -CompressedRowSparseMatrix* IncompleteLQFactorization( - const CompressedRowSparseMatrix& matrix, - const int l_level_of_fill, - const double l_drop_tolerance, - const int q_level_of_fill, - const double q_drop_tolerance) { - const int num_rows = matrix.num_rows(); - const int num_cols = matrix.num_cols(); - const int* rows = matrix.rows(); - const int* cols = matrix.cols(); - const double* values = matrix.values(); - - CompressedRowSparseMatrix* l = - new CompressedRowSparseMatrix(num_rows, - num_rows, - l_level_of_fill * num_rows); - l->set_num_rows(0); - - CompressedRowSparseMatrix q(num_rows, num_cols, q_level_of_fill * num_rows); - q.set_num_rows(0); - - int* l_rows = l->mutable_rows(); - int* l_cols = l->mutable_cols(); - double* l_values = l->mutable_values(); - - int* q_rows = q.mutable_rows(); - int* q_cols = q.mutable_cols(); - double* q_values = q.mutable_values(); - - Vector l_i(num_rows); - Vector q_i(num_cols); - vector<pair<int, double> > scratch(num_cols); - for (int i = 0; i < num_rows; ++i) { - // l_i = q * matrix(i,:)'); - l_i.setZero(); - for (int j = 0; j < i; ++j) { - l_i(j) = RowDotProduct(matrix, i, q, j); - } - DropEntriesAndAddRow(l_i, - i, - l_level_of_fill, - l_drop_tolerance, - &scratch, - l); - - // q_i = matrix(i,:) - q(0:i-1,:) * l_i); - q_i.setZero(); - for (int idx = rows[i]; idx < rows[i + 1]; ++idx) { - q_i(cols[idx]) = values[idx]; - } - - for (int j = l_rows[i]; j < l_rows[i + 1]; ++j) { - const int r = l_cols[j]; - const double lij = l_values[j]; - for (int idx = q_rows[r]; idx < q_rows[r + 1]; ++idx) { - q_i(q_cols[idx]) -= lij * q_values[idx]; - } - } - DropEntriesAndAddRow(q_i, - num_cols, - q_level_of_fill, - q_drop_tolerance, - &scratch, - &q); - - // lii = |qi| - l_cols[l->num_nonzeros()] = i; - l_values[l->num_nonzeros()] = NormalizeRow(i, &q); - l_rows[l->num_rows()] += 1; - } - - return l; -} - -} // namespace internal -} // namespace ceres |