// This file is part of Eigen, a lightweight C++ template library // for linear algebra. // // Copyright (C) 2009 Thomas Capricelli // // This Source Code Form is subject to the terms of the Mozilla // Public License v. 2.0. If a copy of the MPL was not distributed // with this file, You can obtain one at http://mozilla.org/MPL/2.0/. #ifndef EIGEN_NONLINEAROPTIMIZATION_MODULE #define EIGEN_NONLINEAROPTIMIZATION_MODULE #include #include #include #include #include /** * \defgroup NonLinearOptimization_Module Non linear optimization module * * \code * #include * \endcode * * This module provides implementation of two important algorithms in non linear * optimization. In both cases, we consider a system of non linear functions. Of * course, this should work, and even work very well if those functions are * actually linear. But if this is so, you should probably better use other * methods more fitted to this special case. * * One algorithm allows to find an extremum of such a system (Levenberg * Marquardt algorithm) and the second one is used to find * a zero for the system (Powell hybrid "dogleg" method). * * This code is a port of minpack (http://en.wikipedia.org/wiki/MINPACK). * Minpack is a very famous, old, robust and well-reknown package, written in * fortran. Those implementations have been carefully tuned, tested, and used * for several decades. * * The original fortran code was automatically translated using f2c (http://en.wikipedia.org/wiki/F2c) in C, * then c++, and then cleaned by several different authors. * The last one of those cleanings being our starting point : * http://devernay.free.fr/hacks/cminpack.html * * Finally, we ported this code to Eigen, creating classes and API * coherent with Eigen. When possible, we switched to Eigen * implementation, such as most linear algebra (vectors, matrices, stable norms). * * Doing so, we were very careful to check the tests we setup at the very * beginning, which ensure that the same results are found. * * \section Tests Tests * * The tests are placed in the file unsupported/test/NonLinear.cpp. * * There are two kinds of tests : those that come from examples bundled with cminpack. * They guaranty we get the same results as the original algorithms (value for 'x', * for the number of evaluations of the function, and for the number of evaluations * of the jacobian if ever). * * Other tests were added by myself at the very beginning of the * process and check the results for levenberg-marquardt using the reference data * on http://www.itl.nist.gov/div898/strd/nls/nls_main.shtml. Since then i've * carefully checked that the same results were obtained when modifiying the * code. Please note that we do not always get the exact same decimals as they do, * but this is ok : they use 128bits float, and we do the tests using the C type 'double', * which is 64 bits on most platforms (x86 and amd64, at least). * I've performed those tests on several other implementations of levenberg-marquardt, and * (c)minpack performs VERY well compared to those, both in accuracy and speed. * * The documentation for running the tests is on the wiki * http://eigen.tuxfamily.org/index.php?title=Tests * * \section API API : overview of methods * * Both algorithms can use either the jacobian (provided by the user) or compute * an approximation by themselves (actually using Eigen \ref NumericalDiff_Module). * The part of API referring to the latter use 'NumericalDiff' in the method names * (exemple: LevenbergMarquardt.minimizeNumericalDiff() ) * * The methods LevenbergMarquardt.lmder1()/lmdif1()/lmstr1() and * HybridNonLinearSolver.hybrj1()/hybrd1() are specific methods from the original * minpack package that you probably should NOT use until you are porting a code that * was previously using minpack. They just define a 'simple' API with default values * for some parameters. * * All algorithms are provided using Two APIs : * - one where the user inits the algorithm, and uses '*OneStep()' as much as he wants : * this way the caller have control over the steps * - one where the user just calls a method (optimize() or solve()) which will * handle the loop: init + loop until a stop condition is met. Those are provided for * convenience. * * As an example, the method LevenbergMarquardt::minimize() is * implemented as follow : * \code * Status LevenbergMarquardt::minimize(FVectorType &x, const int mode) * { * Status status = minimizeInit(x, mode); * do { * status = minimizeOneStep(x, mode); * } while (status==Running); * return status; * } * \endcode * * \section examples Examples * * The easiest way to understand how to use this module is by looking at the many examples in the file * unsupported/test/NonLinearOptimization.cpp. */ #ifndef EIGEN_PARSED_BY_DOXYGEN #include "src/NonLinearOptimization/qrsolv.h" #include "src/NonLinearOptimization/r1updt.h" #include "src/NonLinearOptimization/r1mpyq.h" #include "src/NonLinearOptimization/rwupdt.h" #include "src/NonLinearOptimization/fdjac1.h" #include "src/NonLinearOptimization/lmpar.h" #include "src/NonLinearOptimization/dogleg.h" #include "src/NonLinearOptimization/covar.h" #include "src/NonLinearOptimization/chkder.h" #endif #include "src/NonLinearOptimization/HybridNonLinearSolver.h" #include "src/NonLinearOptimization/LevenbergMarquardt.h" #endif // EIGEN_NONLINEAROPTIMIZATION_MODULE