gtsam::ISAM2Params Struct Reference

#include <ISAM2Params.h>

Public Types
enum	Factorization { CHOLESKY, QR }
typedef std::variant< ISAM2GaussNewtonParams, ISAM2DoglegParams >	OptimizationParams
typedef std::variant< double, FastMap< char, Vector > >	RelinearizationThreshold

Public Member Functions
	ISAM2Params (OptimizationParams _optimizationParams=ISAM2GaussNewtonParams(), RelinearizationThreshold _relinearizeThreshold=0.1, int _relinearizeSkip=10, bool _enableRelinearization=true, bool _evaluateNonlinearError=false, Factorization _factorization=ISAM2Params::CHOLESKY, bool _cacheLinearizedFactors=true, const KeyFormatter &_keyFormatter=DefaultKeyFormatter, bool _enableDetailedResults=false)
void	print (const std::string &str="") const
	print iSAM2 parameters More...
Getters and Setters for all properties
OptimizationParams	getOptimizationParams () const
RelinearizationThreshold	getRelinearizeThreshold () const
std::string	getFactorization () const
KeyFormatter	getKeyFormatter () const
void	setOptimizationParams (OptimizationParams optimizationParams)
void	setRelinearizeThreshold (RelinearizationThreshold relinearizeThreshold)
void	setFactorization (const std::string &factorization)
void	setKeyFormatter (KeyFormatter keyFormatter)
GaussianFactorGraph::Eliminate	getEliminationFunction () const

Static Public Member Functions
Some utilities
static Factorization	factorizationTranslator (const std::string &str)
static std::string	factorizationTranslator (const Factorization &value)

Public Attributes
bool	cacheLinearizedFactors
bool	enableDetailedResults
bool	enablePartialRelinearizationCheck
bool	enableRelinearization
bool	evaluateNonlinearError
Factorization	factorization
bool	findUnusedFactorSlots
KeyFormatter	keyFormatter
OptimizationParams	optimizationParams
int	relinearizeSkip
RelinearizationThreshold	relinearizeThreshold

Detailed Description

Definition at line 136 of file ISAM2Params.h.

Member Typedef Documentation

OptimizationParams

typedef std::variant<ISAM2GaussNewtonParams, ISAM2DoglegParams> gtsam::ISAM2Params::OptimizationParams

Either ISAM2GaussNewtonParams or ISAM2DoglegParams

Definition at line 138 of file ISAM2Params.h.

RelinearizationThreshold

typedef std::variant<double, FastMap<char, Vector> > gtsam::ISAM2Params::RelinearizationThreshold

Either a constant relinearization threshold or a per-variable-type set of thresholds

Definition at line 141 of file ISAM2Params.h.

Member Enumeration Documentation

Factorization

enum gtsam::ISAM2Params::Factorization

Enumerator
CHOLESKY
QR

Definition at line 182 of file ISAM2Params.h.

Constructor & Destructor Documentation

ISAM2Params()

gtsam::ISAM2Params::ISAM2Params ( OptimizationParams  _optimizationParams = ISAM2GaussNewtonParams(), RelinearizationThreshold  _relinearizeThreshold = 0.1, int  _relinearizeSkip = 10, bool  _enableRelinearization = true, bool  _evaluateNonlinearError = false, Factorization  _factorization = ISAM2Params::CHOLESKY, bool  _cacheLinearizedFactors = true, const KeyFormatter &  _keyFormatter = DefaultKeyFormatter, bool  _enableDetailedResults = false  )

inline

Specify parameters as constructor arguments See the documentation of member variables above.

Parameters

_keyFormatter

see ISAM2::Params::keyFormatter,

Definition at line 231 of file ISAM2Params.h.

Member Function Documentation

factorizationTranslator() [1/2]

string gtsam::ISAM2Params::factorizationTranslator ( const Factorization &  value )

static

Definition at line 73 of file ISAM2Params.cpp.

factorizationTranslator() [2/2]

ISAM2Params::Factorization gtsam::ISAM2Params::factorizationTranslator ( const std::string &  str )

static

Definition at line 60 of file ISAM2Params.cpp.

getEliminationFunction()

GaussianFactorGraph::Eliminate gtsam::ISAM2Params::getEliminationFunction ( ) const

inline

Definition at line 323 of file ISAM2Params.h.

getFactorization()

std::string gtsam::ISAM2Params::getFactorization ( ) const

inline

Definition at line 305 of file ISAM2Params.h.

getKeyFormatter()

KeyFormatter gtsam::ISAM2Params::getKeyFormatter ( ) const

inline

Definition at line 308 of file ISAM2Params.h.

getOptimizationParams()

OptimizationParams gtsam::ISAM2Params::getOptimizationParams ( ) const

inline

Definition at line 299 of file ISAM2Params.h.

getRelinearizeThreshold()

RelinearizationThreshold gtsam::ISAM2Params::getRelinearizeThreshold ( ) const

inline

Definition at line 302 of file ISAM2Params.h.

print()

void gtsam::ISAM2Params::print ( const std::string &  str = "" ) const

inline

print iSAM2 parameters

Definition at line 253 of file ISAM2Params.h.

setFactorization()

void gtsam::ISAM2Params::setFactorization ( const std::string &  factorization )

inline

Definition at line 316 of file ISAM2Params.h.

setKeyFormatter()

void gtsam::ISAM2Params::setKeyFormatter ( KeyFormatter  keyFormatter )

inline

Definition at line 319 of file ISAM2Params.h.

setOptimizationParams()

void gtsam::ISAM2Params::setOptimizationParams ( OptimizationParams  optimizationParams )

inline

Definition at line 310 of file ISAM2Params.h.

setRelinearizeThreshold()

void gtsam::ISAM2Params::setRelinearizeThreshold ( RelinearizationThreshold  relinearizeThreshold )

inline

Definition at line 313 of file ISAM2Params.h.

Member Data Documentation

cacheLinearizedFactors

bool gtsam::ISAM2Params::cacheLinearizedFactors

Whether to cache linear factors (default: true). This can improve performance if linearization is expensive, but can hurt performance if linearization is very cleap due to computation to look up additional keys.

Definition at line 201 of file ISAM2Params.h.

enableDetailedResults

bool gtsam::ISAM2Params::enableDetailedResults

Whether to compute and return ISAM2Result::detailedResults, this can increase running time (default: false)

Definition at line 207 of file ISAM2Params.h.

enablePartialRelinearizationCheck

bool gtsam::ISAM2Params::enablePartialRelinearizationCheck

Check variables for relinearization in tree-order, stopping the check once a variable does not need to be relinearized (default: false). This can improve speed by only checking a small part of the top of the tree. However, variables below the check cut-off can accumulate significant deltas without triggering relinearization. This is particularly useful in exploration scenarios where real-time performance is desired over correctness. Use with caution.

Definition at line 219 of file ISAM2Params.h.

enableRelinearization

bool gtsam::ISAM2Params::enableRelinearization

Controls whether ISAM2 will ever relinearize any variables (default: true)

Definition at line 175 of file ISAM2Params.h.

evaluateNonlinearError

bool gtsam::ISAM2Params::evaluateNonlinearError

Whether to evaluate the nonlinear error before and after the update, to return in ISAM2Result from update()

Definition at line 178 of file ISAM2Params.h.

factorization

Factorization gtsam::ISAM2Params::factorization

Specifies whether to use QR or CHOESKY numerical factorization (default: CHOLESKY). Cholesky is faster but potentially numerically unstable for poorly-conditioned problems, which can occur when uncertainty is very low in some variables (or dimensions of variables) and very high in others. QR is slower but more numerically stable in poorly-conditioned problems. We suggest using the default of Cholesky unless gtsam sometimes throws IndefiniteLinearSystemException when your problem's Hessian is actually positive definite. For positive definite problems, numerical error accumulation can cause the problem to become numerically negative or indefinite as solving proceeds, especially when using Cholesky.

Definition at line 194 of file ISAM2Params.h.

findUnusedFactorSlots

bool gtsam::ISAM2Params::findUnusedFactorSlots

When you will be removing many factors, e.g. when using ISAM2 as a fixed-lag smoother, enable this option to add factors in the first available factor slots, to avoid accumulating nullptr factor slots, at the cost of having to search for slots every time a factor is added.

Definition at line 225 of file ISAM2Params.h.

keyFormatter

KeyFormatter gtsam::ISAM2Params::keyFormatter

A KeyFormatter for when keys are printed during debugging (default: DefaultKeyFormatter)

Definition at line 204 of file ISAM2Params.h.

optimizationParams

OptimizationParams gtsam::ISAM2Params::optimizationParams

Optimization parameters, this both selects the nonlinear optimization method and specifies its parameters, either ISAM2GaussNewtonParams or ISAM2DoglegParams. In the former, Gauss-Newton optimization will be used with the specified parameters, and in the latter Powell's dog-leg algorithm will be used with the specified parameters.

Definition at line 151 of file ISAM2Params.h.

relinearizeSkip

int gtsam::ISAM2Params::relinearizeSkip

Only relinearize any variables every relinearizeSkip calls to ISAM2::update (default: 10)

Definition at line 171 of file ISAM2Params.h.

relinearizeThreshold

RelinearizationThreshold gtsam::ISAM2Params::relinearizeThreshold

Only relinearize variables whose linear delta magnitude is greater than this threshold (default: 0.1). If this is a FastMap<char,Vector> instead of a double, then the threshold is specified for each dimension of each variable type. This parameter then maps from a character indicating the variable type to a Vector of thresholds for each dimension of that variable. For example, if Pose keys are of type TypedSymbol<'x',Pose3>, and landmark keys are of type TypedSymbol<'l',Point3>, then appropriate entries would be added with:

  FastMap<char,Vector> thresholds;
  thresholds['x'] = (Vector(6) << 0.1, 0.1, 0.1, 0.5, 0.5, 0.5).finished();
// 0.1 rad rotation threshold, 0.5 m translation threshold thresholds['l'] =
Vector3(1.0, 1.0, 1.0);                // 1.0 m landmark position threshold
  params.relinearizeThreshold = thresholds;

Definition at line 169 of file ISAM2Params.h.

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The documentation for this struct was generated from the following files:

• ISAM2Params.h
• ISAM2Params.cpp