10ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// Ceres Solver - A fast non-linear least squares minimizer 20ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// Copyright 2012 Google Inc. All rights reserved. 30ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// http://code.google.com/p/ceres-solver/ 40ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// 50ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// Redistribution and use in source and binary forms, with or without 60ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// modification, are permitted provided that the following conditions are met: 70ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// 80ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// * Redistributions of source code must retain the above copyright notice, 90ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// this list of conditions and the following disclaimer. 100ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// * Redistributions in binary form must reproduce the above copyright notice, 110ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// this list of conditions and the following disclaimer in the documentation 120ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// and/or other materials provided with the distribution. 130ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// * Neither the name of Google Inc. nor the names of its contributors may be 140ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// used to endorse or promote products derived from this software without 150ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// specific prior written permission. 160ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// 170ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 180ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 190ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 200ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 210ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 220ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 230ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 240ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 250ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 260ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 270ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// POSSIBILITY OF SUCH DAMAGE. 280ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// 290ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// Author: sameeragarwal@google.com (Sameer Agarwal) 300ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong 310ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong#ifndef CERES_INTERNAL_LEVENBERG_MARQUARDT_STRATEGY_H_ 320ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong#define CERES_INTERNAL_LEVENBERG_MARQUARDT_STRATEGY_H_ 330ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong 340ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong#include "ceres/internal/eigen.h" 350ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong#include "ceres/trust_region_strategy.h" 360ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong 370ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kongnamespace ceres { 380ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kongnamespace internal { 390ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong 400ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// Levenberg-Marquardt step computation and trust region sizing 410ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// strategy based on on "Methods for Nonlinear Least Squares" by 420ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// K. Madsen, H.B. Nielsen and O. Tingleff. Available to download from 430ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// 440ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong// http://www2.imm.dtu.dk/pubdb/views/edoc_download.php/3215/pdf/imm3215.pdf 450ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kongclass LevenbergMarquardtStrategy : public TrustRegionStrategy { 461d2624a10e2c559f8ba9ef89eaa30832c0a83a96Sascha Haeberling public: 471d2624a10e2c559f8ba9ef89eaa30832c0a83a96Sascha Haeberling explicit LevenbergMarquardtStrategy( 481d2624a10e2c559f8ba9ef89eaa30832c0a83a96Sascha Haeberling const TrustRegionStrategy::Options& options); 490ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong virtual ~LevenbergMarquardtStrategy(); 500ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong 510ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong // TrustRegionStrategy interface 520ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong virtual TrustRegionStrategy::Summary ComputeStep( 530ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong const TrustRegionStrategy::PerSolveOptions& per_solve_options, 540ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong SparseMatrix* jacobian, 550ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong const double* residuals, 560ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong double* step); 570ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong virtual void StepAccepted(double step_quality); 580ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong virtual void StepRejected(double step_quality); 590ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong virtual void StepIsInvalid() { 600ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong // Treat the current step as a rejected step with no increase in 610ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong // solution quality. Since rejected steps lead to decrease in the 620ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong // size of the trust region, the next time ComputeStep is called, 630ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong // this will lead to a better conditioned system. 640ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong StepRejected(0.0); 650ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong } 660ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong 670ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong virtual double Radius() const; 680ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong 690ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong private: 700ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong LinearSolver* linear_solver_; 710ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong double radius_; 720ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong double max_radius_; 730ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong const double min_diagonal_; 740ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong const double max_diagonal_; 750ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong double decrease_factor_; 760ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong bool reuse_diagonal_; 770ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong Vector diagonal_; // diagonal_ = diag(J'J) 780ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong // Scaled copy of diagonal_. Stored here as optimization to prevent 790ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong // allocations in every iteration and reuse when a step fails and 800ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong // ComputeStep is called again. 810ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong Vector lm_diagonal_; // lm_diagonal_ = diagonal_ / radius_; 820ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong}; 830ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong 840ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong} // namespace internal 850ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong} // namespace ceres 860ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong 870ae28bd5885b5daa526898fcf7c323dc2c3e1963Angus Kong#endif // CERES_INTERNAL_LEVENBERG_MARQUARDT_STRATEGY_H_ 88