1 files changed, 90 insertions, 0 deletions
diff --git a/internal/ceres/dense_qr_solver.cc b/internal/ceres/dense_qr_solver.cc
new file mode 100644
index 0000000..7aec450
--- /dev/null
+++ b/internal/ceres/dense_qr_solver.cc
@@ -0,0 +1,90 @@
+// Ceres Solver - A fast non-linear least squares minimizer
+// Copyright 2010, 2011, 2012 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/dense_qr_solver.h"
+
+#include <cstddef>
+
+#include "Eigen/Dense"
+#include "ceres/dense_sparse_matrix.h"
+#include "ceres/linear_solver.h"
+#include "ceres/internal/eigen.h"
+#include "ceres/internal/scoped_ptr.h"
+#include "ceres/types.h"
+
+namespace ceres {
+namespace internal {
+
+DenseQRSolver::DenseQRSolver(const LinearSolver::Options& options)
+    : options_(options) {}
+
+LinearSolver::Summary DenseQRSolver::SolveImpl(
+    DenseSparseMatrix* A,
+    const double* b,
+    const LinearSolver::PerSolveOptions& per_solve_options,
+    double* x) {
+  const int num_rows = A->num_rows();
+  const int num_cols = A->num_cols();
+  VLOG(2) << "DenseQRSolver: "
+          << num_rows << " x " << num_cols << " system.";
+
+  if (per_solve_options.D != NULL) {
+    // Temporarily append a diagonal block to the A matrix, but undo
+    // it before returning the matrix to the user.
+    A->AppendDiagonal(per_solve_options.D);
+  }
+
+  // rhs = [b;0] to account for the additional rows in the lhs.
+  const int augmented_num_rows = num_rows + ((per_solve_options.D != NULL) ? num_cols : 0);
+  if (rhs_.rows() != augmented_num_rows) {
+    rhs_.resize(augmented_num_rows);
+    rhs_.setZero();
+  }
+  rhs_.head(num_rows) = ConstVectorRef(b, num_rows);
+
+  // Solve the system.
+  VectorRef(x, num_cols) = A->matrix().colPivHouseholderQr().solve(rhs_);
+
+  if (per_solve_options.D != NULL) {
+    // Undo the modifications to the matrix A.
+    A->RemoveDiagonal();
+  }
+
+  // We always succeed, since the QR solver returns the best solution
+  // it can. It is the job of the caller to determine if the solution
+  // is good enough or not.
+  LinearSolver::Summary summary;
+  summary.num_iterations = 1;
+  summary.termination_type = TOLERANCE;
+  return summary;
+}
+
+}   // namespace internal
+}   // namespace ceres