#include <itkGradientDescentLineSearchOptimizerv4.h>

Detailed Description

template<typename TInternalComputationValueType>
class itk::GradientDescentLineSearchOptimizerv4Template< TInternalComputationValueType >

Gradient descent optimizer with a golden section line search.

GradientDescentLineSearchOptimizer implements a simple gradient descent optimizer that is followed by a line search to find the best value for the learning rate. At each iteration the current position is updated according to

\[ p_{n+1} = p_n + \mbox{learningRateByGoldenSectionLineSearch} \, \frac{\partial f(p_n) }{\partial p_n} \]

Options are identical to the superclass's except for:

options Epsilon, LowerLimit and UpperLimit that will guide a golden section line search to find the optimal gradient update within the range :

[ learningRate * LowerLimit , learningRate * UpperLimit ]

where Epsilon sets the resolution of the search. Smaller values lead to additional computation time but better localization of the minimum.

By default, this optimizer will return the best value and associated parameters that were calculated during the optimization. See SetReturnBestParametersAndValue().

Definition at line 60 of file itkGradientDescentLineSearchOptimizerv4.h.

Inheritance diagram for itk::GradientDescentLineSearchOptimizerv4Template< TInternalComputationValueType >:

Collaboration diagram for itk::GradientDescentLineSearchOptimizerv4Template< TInternalComputationValueType >:

Public Types
using	ConstPointer = SmartPointer< const Self >

using	ConvergenceMonitoringType = itk::Function::WindowConvergenceMonitoringFunction< TInternalComputationValueType >

using	InternalComputationValueType = TInternalComputationValueType

using	Pointer = SmartPointer< Self >

using	Self = GradientDescentLineSearchOptimizerv4Template

using	Superclass = GradientDescentOptimizerv4Template< TInternalComputationValueType >

Public Types inherited from itk::GradientDescentOptimizerv4Template< TInternalComputationValueType >
using	ConstPointer = SmartPointer< const Self >

using	InternalComputationValueType = TInternalComputationValueType

using	Pointer = SmartPointer< Self >

using	Self = GradientDescentOptimizerv4Template

using	Superclass = GradientDescentOptimizerBasev4Template< TInternalComputationValueType >

Public Types inherited from itk::GradientDescentOptimizerBasev4Template< TInternalComputationValueType >
using	ConstPointer = SmartPointer< const Self >

using	ConvergenceMonitoringType = itk::Function::WindowConvergenceMonitoringFunction< TInternalComputationValueType >

using	IndexRangeType = ThreadedIndexedContainerPartitioner::IndexRangeType

using	InternalComputationValueType = TInternalComputationValueType

using	MetricTypePointer = typename MetricType::Pointer

using	Pointer = SmartPointer< Self >

using	Self = GradientDescentOptimizerBasev4Template

using	Superclass = ObjectToObjectOptimizerBaseTemplate< TInternalComputationValueType >

Public Types inherited from itk::ObjectToObjectOptimizerBaseTemplate< TInternalComputationValueType >
using	ConstPointer = SmartPointer< const Self >

using	DerivativeType = typename MetricType::DerivativeType

using	MeasureType = typename MetricType::MeasureType

using	MetricType = ObjectToObjectMetricBaseTemplate< TInternalComputationValueType >

using	MetricTypePointer = typename MetricType::Pointer

using	NumberOfParametersType = typename MetricType::NumberOfParametersType

using	ParametersType = OptimizerParameters< TInternalComputationValueType >

using	Pointer = SmartPointer< Self >

using	ScalesEstimatorType = OptimizerParameterScalesEstimatorTemplate< TInternalComputationValueType >

using	ScalesType = OptimizerParameters< TInternalComputationValueType >

using	Self = ObjectToObjectOptimizerBaseTemplate

using	StopConditionDescriptionType = std::ostringstream

using	StopConditionReturnStringType = std::string

using	Superclass = Object

Public Types inherited from itk::Object
using	ConstPointer = SmartPointer< const Self >

using	Pointer = SmartPointer< Self >

using	Self = Object

using	Superclass = LightObject

Public Types inherited from itk::LightObject
using	ConstPointer = SmartPointer< const Self >

using	Pointer = SmartPointer< Self >

using	Self = LightObject

Public Member Functions
const char *	GetNameOfClass () const override


virtual void	SetEpsilon (TInternalComputationValueType _arg)

virtual TInternalComputationValueType	GetEpsilon ()


virtual void	SetLowerLimit (TInternalComputationValueType _arg)

virtual TInternalComputationValueType	GetLowerLimit ()

virtual void	SetUpperLimit (TInternalComputationValueType _arg)

virtual TInternalComputationValueType	GetUpperLimit ()

virtual void	SetMaximumLineSearchIterations (unsigned int _arg)

virtual unsigned int	GetMaximumLineSearchIterations ()

Public Member Functions inherited from itk::GradientDescentOptimizerv4Template< TInternalComputationValueType >
virtual void	EstimateLearningRate ()

virtual const TInternalComputationValueType &	GetConvergenceValue () const

const char *	GetNameOfClass () const override

void	ResumeOptimization () override

virtual void	SetConvergenceWindowSize (SizeValueType _arg)

virtual void	SetMinimumConvergenceValue (TInternalComputationValueType _arg)

void	StartOptimization (bool doOnlyInitialization=false) override

void	StopOptimization () override

virtual void	SetLearningRate (TInternalComputationValueType _arg)

virtual const TInternalComputationValueType &	GetLearningRate () const

virtual void	SetMaximumStepSizeInPhysicalUnits (TInternalComputationValueType _arg)

virtual const TInternalComputationValueType &	GetMaximumStepSizeInPhysicalUnits () const

virtual void	SetDoEstimateLearningRateAtEachIteration (bool _arg)

virtual const bool &	GetDoEstimateLearningRateAtEachIteration () const

virtual void	DoEstimateLearningRateAtEachIterationOn ()

virtual void	SetDoEstimateLearningRateOnce (bool _arg)

virtual const bool &	GetDoEstimateLearningRateOnce () const

virtual void	DoEstimateLearningRateOnceOn ()

virtual void	SetReturnBestParametersAndValue (bool _arg)

virtual const bool &	GetReturnBestParametersAndValue () const

virtual void	ReturnBestParametersAndValueOn ()

Public Member Functions inherited from itk::GradientDescentOptimizerBasev4Template< TInternalComputationValueType >
virtual const DerivativeType &	GetGradient () const

const char *	GetNameOfClass () const override

virtual const StopConditionObjectToObjectOptimizerEnum &	GetStopCondition () const

StopConditionReturnStringType	GetStopConditionDescription () const override

virtual void	ModifyGradientByLearningRateOverSubRange (const IndexRangeType &subrange)=0

virtual void	ModifyGradientByScalesOverSubRange (const IndexRangeType &subrange)=0

virtual void	ResumeOptimization ()=0

void	StartOptimization (bool doOnlyInitialization=false) override

virtual void	StopOptimization ()

virtual void	ModifyGradientByScales ()

virtual void	ModifyGradientByLearningRate ()

Public Member Functions inherited from itk::ObjectToObjectOptimizerBaseTemplate< TInternalComputationValueType >
virtual bool	CanUseScales () const

virtual SizeValueType	GetCurrentIteration () const

virtual const MeasureType &	GetCurrentMetricValue () const

virtual const ParametersType &	GetCurrentPosition () const

const char *	GetNameOfClass () const override

virtual SizeValueType	GetNumberOfIterations () const

virtual const ThreadIdType &	GetNumberOfWorkUnits () const

virtual const ScalesType &	GetScales () const

virtual const bool &	GetScalesAreIdentity () const

bool	GetScalesInitialized () const

virtual StopConditionReturnStringType	GetStopConditionDescription () const=0

virtual const MeasureType &	GetValue () const

virtual const ScalesType &	GetWeights () const

virtual const bool &	GetWeightsAreIdentity () const

virtual void	SetNumberOfIterations (SizeValueType _arg)

virtual void	SetNumberOfWorkUnits (ThreadIdType number)

virtual void	SetScalesEstimator (ScalesEstimatorType *_arg)

virtual void	SetWeights (ScalesType _arg)

virtual void	StartOptimization (bool doOnlyInitialization=false)

virtual void	SetMetric (MetricType *_arg)

virtual MetricType *	GetModifiableMetric ()

virtual void	SetScales (const ScalesType &scales)

virtual void	SetDoEstimateScales (bool _arg)

virtual const bool &	GetDoEstimateScales () const

virtual void	DoEstimateScalesOn ()

Public Member Functions inherited from itk::Object
unsigned long	AddObserver (const EventObject &event, Command *cmd) const

unsigned long	AddObserver (const EventObject &event, std::function< void(const EventObject &)> function) const

LightObject::Pointer	CreateAnother () const override

virtual void	DebugOff () const

virtual void	DebugOn () const

Command *	GetCommand (unsigned long tag)

bool	GetDebug () const

MetaDataDictionary &	GetMetaDataDictionary ()

const MetaDataDictionary &	GetMetaDataDictionary () const

virtual ModifiedTimeType	GetMTime () const

const char *	GetNameOfClass () const override

virtual const TimeStamp &	GetTimeStamp () const

bool	HasObserver (const EventObject &event) const

void	InvokeEvent (const EventObject &)

void	InvokeEvent (const EventObject &) const

virtual void	Modified () const

void	Register () const override

void	RemoveAllObservers ()

void	RemoveObserver (unsigned long tag) const

void	SetDebug (bool debugFlag) const

void	SetReferenceCount (int) override

void	UnRegister () const noexcept override

void	SetMetaDataDictionary (const MetaDataDictionary &rhs)

void	SetMetaDataDictionary (MetaDataDictionary &&rrhs)

virtual void	SetObjectName (std::string _arg)

virtual const std::string &	GetObjectName () const

Public Member Functions inherited from itk::LightObject
Pointer	Clone () const

virtual Pointer	CreateAnother () const

virtual void	Delete ()

virtual const char *	GetNameOfClass () const

virtual int	GetReferenceCount () const

void	Print (std::ostream &os, Indent indent=0) const

virtual void	Register () const

virtual void	SetReferenceCount (int)

virtual void	UnRegister () const noexcept

Static Public Member Functions
static Pointer	New ()

Static Public Member Functions inherited from itk::GradientDescentOptimizerv4Template< TInternalComputationValueType >
static Pointer	New ()

Static Public Member Functions inherited from itk::Object
static bool	GetGlobalWarningDisplay ()

static void	GlobalWarningDisplayOff ()

static void	GlobalWarningDisplayOn ()

static Pointer	New ()

static void	SetGlobalWarningDisplay (bool val)

Static Public Member Functions inherited from itk::LightObject
static void	BreakOnError ()

static Pointer	New ()

Protected Member Functions
void	AdvanceOneStep () override

	GradientDescentLineSearchOptimizerv4Template ()

void	PrintSelf (std::ostream &os, Indent indent) const override

	~GradientDescentLineSearchOptimizerv4Template () override=default


TInternalComputationValueType	GoldenSectionSearch (TInternalComputationValueType a, TInternalComputationValueType b, TInternalComputationValueType c, TInternalComputationValueType metricb=NumericTraits< TInternalComputationValueType >::max())

Protected Member Functions inherited from itk::GradientDescentOptimizerv4Template< TInternalComputationValueType >
virtual void	AdvanceOneStep ()

	GradientDescentOptimizerv4Template ()

void	ModifyGradientByLearningRateOverSubRange (const IndexRangeType &subrange) override

void	ModifyGradientByScalesOverSubRange (const IndexRangeType &subrange) override

void	PrintSelf (std::ostream &os, Indent indent) const override

	~GradientDescentOptimizerv4Template () override=default

Protected Member Functions inherited from itk::GradientDescentOptimizerBasev4Template< TInternalComputationValueType >
void	PrintSelf (std::ostream &os, Indent indent) const override

	GradientDescentOptimizerBasev4Template ()

	~GradientDescentOptimizerBasev4Template () override=default

Protected Member Functions inherited from itk::ObjectToObjectOptimizerBaseTemplate< TInternalComputationValueType >
void	PrintSelf (std::ostream &os, Indent indent) const override

	ObjectToObjectOptimizerBaseTemplate ()

	~ObjectToObjectOptimizerBaseTemplate () override

Protected Member Functions inherited from itk::Object
	Object ()

bool	PrintObservers (std::ostream &os, Indent indent) const

void	PrintSelf (std::ostream &os, Indent indent) const override

virtual void	SetTimeStamp (const TimeStamp &timeStamp)

	~Object () override

Protected Member Functions inherited from itk::LightObject
virtual LightObject::Pointer	InternalClone () const

	LightObject ()

virtual void	PrintHeader (std::ostream &os, Indent indent) const

virtual void	PrintSelf (std::ostream &os, Indent indent) const

virtual void	PrintTrailer (std::ostream &os, Indent indent) const

virtual	~LightObject ()

Protected Attributes
TInternalComputationValueType	m_Epsilon {}

unsigned int	m_LineSearchIterations {}

TInternalComputationValueType	m_LowerLimit {}

unsigned int	m_MaximumLineSearchIterations {}

TInternalComputationValueType	m_Phi {}

TInternalComputationValueType	m_Resphi {}

TInternalComputationValueType	m_UpperLimit {}

Protected Attributes inherited from itk::GradientDescentOptimizerv4Template< TInternalComputationValueType >
ParametersType	m_BestParameters {}

TInternalComputationValueType	m_ConvergenceValue {}

MeasureType	m_CurrentBestValue {}

TInternalComputationValueType	m_LearningRate {}

TInternalComputationValueType	m_MinimumConvergenceValue {}

DerivativeType	m_PreviousGradient {}

bool	m_ReturnBestParametersAndValue { false }

Protected Attributes inherited from itk::GradientDescentOptimizerBasev4Template< TInternalComputationValueType >
ConvergenceMonitoringType::Pointer	m_ConvergenceMonitoring {}

SizeValueType	m_ConvergenceWindowSize {}

bool	m_DoEstimateLearningRateAtEachIteration {}

bool	m_DoEstimateLearningRateOnce {}

DerivativeType	m_Gradient {}

TInternalComputationValueType	m_MaximumStepSizeInPhysicalUnits {}

DomainThreader< ThreadedIndexedContainerPartitioner, Self >::Pointer	m_ModifyGradientByLearningRateThreader {}

DomainThreader< ThreadedIndexedContainerPartitioner, Self >::Pointer	m_ModifyGradientByScalesThreader {}

bool	m_Stop { false }

StopConditionObjectToObjectOptimizerEnum	m_StopCondition {}

StopConditionDescriptionType	m_StopConditionDescription {}

bool	m_UseConvergenceMonitoring {}

Protected Attributes inherited from itk::ObjectToObjectOptimizerBaseTemplate< TInternalComputationValueType >
SizeValueType	m_CurrentIteration

MeasureType	m_CurrentMetricValue

bool	m_DoEstimateScales

MetricTypePointer	m_Metric

SizeValueType	m_NumberOfIterations

ThreadIdType	m_NumberOfWorkUnits

ScalesType	m_Scales

bool	m_ScalesAreIdentity

ScalesEstimatorType::Pointer	m_ScalesEstimator

ScalesType	m_Weights

bool	m_WeightsAreIdentity

Protected Attributes inherited from itk::LightObject
std::atomic< int >	m_ReferenceCount {}