1 // Ceres Solver - A fast non-linear least squares minimizer 2 // Copyright 2012 Google Inc. All rights reserved. 3 // http://code.google.com/p/ceres-solver/ 4 // 5 // Redistribution and use in source and binary forms, with or without 6 // modification, are permitted provided that the following conditions are met: 7 // 8 // * Redistributions of source code must retain the above copyright notice, 9 // this list of conditions and the following disclaimer. 10 // * Redistributions in binary form must reproduce the above copyright notice, 11 // this list of conditions and the following disclaimer in the documentation 12 // and/or other materials provided with the distribution. 13 // * Neither the name of Google Inc. nor the names of its contributors may be 14 // used to endorse or promote products derived from this software without 15 // specific prior written permission. 16 // 17 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 18 // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 // ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 21 // LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 22 // CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 23 // SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 24 // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 25 // CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 26 // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 27 // POSSIBILITY OF SUCH DAMAGE. 28 // 29 // Author: keir@google.com (Keir Mierle) 30 31 #ifndef CERES_INTERNAL_CGNR_SOLVER_H_ 32 #define CERES_INTERNAL_CGNR_SOLVER_H_ 33 34 #include "ceres/internal/scoped_ptr.h" 35 #include "ceres/linear_solver.h" 36 37 namespace ceres { 38 namespace internal { 39 40 class BlockJacobiPreconditioner; 41 42 // A conjugate gradients on the normal equations solver. This directly solves 43 // for the solution to 44 // 45 // (A^T A + D^T D)x = A^T b 46 // 47 // as required for solving for x in the least squares sense. Currently only 48 // block diagonal preconditioning is supported. 49 class CgnrSolver : public LinearSolver { 50 public: 51 explicit CgnrSolver(const LinearSolver::Options& options); 52 virtual Summary Solve(LinearOperator* A, 53 const double* b, 54 const LinearSolver::PerSolveOptions& per_solve_options, 55 double* x); 56 57 private: 58 const LinearSolver::Options options_; 59 scoped_ptr<BlockJacobiPreconditioner> jacobi_preconditioner_; 60 CERES_DISALLOW_COPY_AND_ASSIGN(CgnrSolver); 61 }; 62 63 } // namespace internal 64 } // namespace ceres 65 66 #endif // CERES_INTERNAL_CGNR_SOLVER_H_ 67