gtsam/gtsam/nonlinear/LevenbergMarquardtOptimizer.h

285 lines
9.3 KiB
C++

/* ----------------------------------------------------------------------------
* GTSAM Copyright 2010, Georgia Tech Research Corporation,
* Atlanta, Georgia 30332-0415
* All Rights Reserved
* Authors: Frank Dellaert, et al. (see THANKS for the full author list)
* See LICENSE for the license information
* -------------------------------------------------------------------------- */
/**
* @file LevenbergMarquardtOptimizer.h
* @brief
* @author Richard Roberts
* @date Feb 26, 2012
*/
#pragma once
#include <gtsam/nonlinear/NonlinearOptimizer.h>
#include <gtsam/linear/VectorValues.h>
#include <boost/date_time/posix_time/posix_time.hpp>
class NonlinearOptimizerMoreOptimizationTest;
namespace gtsam {
class LevenbergMarquardtOptimizer;
/** Parameters for Levenberg-Marquardt optimization. Note that this parameters
* class inherits from NonlinearOptimizerParams, which specifies the parameters
* common to all nonlinear optimization algorithms. This class also contains
* all of those parameters.
*/
class GTSAM_EXPORT LevenbergMarquardtParams: public NonlinearOptimizerParams {
public:
/** See LevenbergMarquardtParams::lmVerbosity */
enum VerbosityLM {
SILENT = 0, TERMINATION, LAMBDA, TRYLAMBDA, TRYCONFIG, DAMPED, TRYDELTA
};
static VerbosityLM verbosityLMTranslator(const std::string &s);
static std::string verbosityLMTranslator(VerbosityLM value);
public:
double lambdaInitial; ///< The initial Levenberg-Marquardt damping term (default: 1e-5)
double lambdaFactor; ///< The amount by which to multiply or divide lambda when adjusting lambda (default: 10.0)
double lambdaUpperBound; ///< The maximum lambda to try before assuming the optimization has failed (default: 1e5)
double lambdaLowerBound; ///< The minimum lambda used in LM (default: 0)
VerbosityLM verbosityLM; ///< The verbosity level for Levenberg-Marquardt (default: SILENT), see also NonlinearOptimizerParams::verbosity
double minModelFidelity; ///< Lower bound for the modelFidelity to accept the result of an LM iteration
std::string logFile; ///< an optional CSV log file, with [iteration, time, error, labda]
bool diagonalDamping; ///< if true, use diagonal of Hessian
bool reuse_diagonal_; ///< an additional option in Ceres for diagonalDamping (related to efficiency)
bool useFixedLambdaFactor_; ///< if true applies constant increase (or decrease) to lambda according to lambdaFactor
double min_diagonal_; ///< when using diagonal damping saturates the minimum diagonal entries (default: 1e-6)
double max_diagonal_; ///< when using diagonal damping saturates the maximum diagonal entries (default: 1e32)
LevenbergMarquardtParams() :
lambdaInitial(1e-5), lambdaFactor(10.0), lambdaUpperBound(1e5), lambdaLowerBound(
0.0), verbosityLM(SILENT), minModelFidelity(1e-3),
diagonalDamping(false), reuse_diagonal_(false), useFixedLambdaFactor_(true),
min_diagonal_(1e-6), max_diagonal_(1e32) {
}
virtual ~LevenbergMarquardtParams() {
}
virtual void print(const std::string& str = "") const;
inline double getlambdaInitial() const {
return lambdaInitial;
}
inline double getlambdaFactor() const {
return lambdaFactor;
}
inline double getlambdaUpperBound() const {
return lambdaUpperBound;
}
inline double getlambdaLowerBound() const {
return lambdaLowerBound;
}
inline std::string getVerbosityLM() const {
return verbosityLMTranslator(verbosityLM);
}
inline std::string getLogFile() const {
return logFile;
}
inline bool getDiagonalDamping() const {
return diagonalDamping;
}
inline void setlambdaInitial(double value) {
lambdaInitial = value;
}
inline void setlambdaFactor(double value) {
lambdaFactor = value;
}
inline void setlambdaUpperBound(double value) {
lambdaUpperBound = value;
}
inline void setlambdaLowerBound(double value) {
lambdaLowerBound = value;
}
inline void setVerbosityLM(const std::string &s) {
verbosityLM = verbosityLMTranslator(s);
}
inline void setLogFile(const std::string &s) {
logFile = s;
}
inline void setDiagonalDamping(bool flag) {
diagonalDamping = flag;
}
inline void setUseFixedLambdaFactor(bool flag) {
useFixedLambdaFactor_ = flag;
}
};
/**
* State for LevenbergMarquardtOptimizer
*/
class GTSAM_EXPORT LevenbergMarquardtState: public NonlinearOptimizerState {
public:
double lambda;
int totalNumberInnerIterations; // The total number of inner iterations in the optimization (for each iteration, LM may try multiple iterations with different lambdas)
boost::posix_time::ptime startTime;
VectorValues hessianDiagonal; //only update hessianDiagonal when reuse_diagonal_ = false
LevenbergMarquardtState() {
initTime();
}
void initTime() {
startTime = boost::posix_time::microsec_clock::universal_time();
}
virtual ~LevenbergMarquardtState() {
}
protected:
LevenbergMarquardtState(const NonlinearFactorGraph& graph,
const Values& initialValues, const LevenbergMarquardtParams& params,
unsigned int iterations = 0) :
NonlinearOptimizerState(graph, initialValues, iterations), lambda(
params.lambdaInitial), totalNumberInnerIterations(0) {
initTime();
}
friend class LevenbergMarquardtOptimizer;
};
/**
* This class performs Levenberg-Marquardt nonlinear optimization
*/
class GTSAM_EXPORT LevenbergMarquardtOptimizer: public NonlinearOptimizer {
protected:
LevenbergMarquardtParams params_; ///< LM parameters
LevenbergMarquardtState state_; ///< optimization state
public:
typedef boost::shared_ptr<LevenbergMarquardtOptimizer> shared_ptr;
/// @name Standard interface
/// @{
/** Standard constructor, requires a nonlinear factor graph, initial
* variable assignments, and optimization parameters. For convenience this
* version takes plain objects instead of shared pointers, but internally
* copies the objects.
* @param graph The nonlinear factor graph to optimize
* @param initialValues The initial variable assignments
* @param params The optimization parameters
*/
LevenbergMarquardtOptimizer(const NonlinearFactorGraph& graph,
const Values& initialValues, const LevenbergMarquardtParams& params =
LevenbergMarquardtParams()) :
NonlinearOptimizer(graph), params_(ensureHasOrdering(params, graph)), state_(
graph, initialValues, params_) {
}
/** Standard constructor, requires a nonlinear factor graph, initial
* variable assignments, and optimization parameters. For convenience this
* version takes plain objects instead of shared pointers, but internally
* copies the objects.
* @param graph The nonlinear factor graph to optimize
* @param initialValues The initial variable assignments
*/
LevenbergMarquardtOptimizer(const NonlinearFactorGraph& graph,
const Values& initialValues, const Ordering& ordering) :
NonlinearOptimizer(graph) {
params_.ordering = ordering;
state_ = LevenbergMarquardtState(graph, initialValues, params_);
}
/// Access the current damping value
double lambda() const {
return state_.lambda;
}
// Apply policy to increase lambda if the current update was successful (stepQuality not used in the naive policy)
void increaseLambda();
// Apply policy to decrease lambda if the current update was NOT successful (stepQuality not used in the naive policy)
void decreaseLambda(double stepQuality);
/// Access the current number of inner iterations
int getInnerIterations() const {
return state_.totalNumberInnerIterations;
}
/// print
virtual void print(const std::string& str = "") const {
std::cout << str << "LevenbergMarquardtOptimizer" << std::endl;
this->params_.print(" parameters:\n");
}
/// @}
/// @name Advanced interface
/// @{
/** Virtual destructor */
virtual ~LevenbergMarquardtOptimizer() {
}
/** Perform a single iteration, returning a new NonlinearOptimizer class
* containing the updated variable assignments, which may be retrieved with
* values().
*/
virtual void iterate();
/** Read-only access the parameters */
const LevenbergMarquardtParams& params() const {
return params_;
}
/** Read/write access the parameters */
LevenbergMarquardtParams& params() {
return params_;
}
/** Read-only access the last state */
const LevenbergMarquardtState& state() const {
return state_;
}
/** Read/write access the last state. When modifying the state, the error, etc. must be consistent before calling iterate() */
LevenbergMarquardtState& state() {
return state_;
}
/** Build a damped system for a specific lambda */
GaussianFactorGraph::shared_ptr buildDampedSystem(const GaussianFactorGraph& linear);
friend class ::NonlinearOptimizerMoreOptimizationTest;
void writeLogFile(double currentError);
/// @}
protected:
/** Access the parameters (base class version) */
virtual const NonlinearOptimizerParams& _params() const {
return params_;
}
/** Access the state (base class version) */
virtual const NonlinearOptimizerState& _state() const {
return state_;
}
/** Internal function for computing a COLAMD ordering if no ordering is specified */
LevenbergMarquardtParams ensureHasOrdering(LevenbergMarquardtParams params,
const NonlinearFactorGraph& graph) const;
/** linearize, can be overwritten */
virtual GaussianFactorGraph::shared_ptr linearize() const;
};
}