Constrained Sphere function. More...

#include <shark/ObjectiveFunctions/Benchmarks/ConstrainedSphere.h>

Inheritance diagram for shark::ConstrainedSphere:

Public Member Functions
	ConstrainedSphere (std::size_t numberOfVariables=5, std::size_t m=1)

std::string	name () const
	From INameable: return the class name. More...

std::size_t	numberOfVariables () const
	Accesses the number of variables. More...

bool	hasScalableDimensionality () const

void	setNumberOfVariables (std::size_t numberOfVariables)
	Adjusts the number of variables if the function is scalable. More...

SearchPointType	proposeStartingPoint () const
	Proposes a starting point in the feasible search space of the function. More...

bool	isFeasible (SearchPointType const &input) const
	Tests whether a point in SearchSpace is feasible, e.g., whether the constraints are fulfilled. More...

double	eval (const SearchPointType &p) const
	Evaluates the objective function for the supplied argument. More...

Public Member Functions inherited from shark::AbstractObjectiveFunction< PointType, ResultT >
const Features &	features () const

virtual void	updateFeatures ()

bool	hasValue () const
	returns whether this function can calculate it's function value More...

bool	hasFirstDerivative () const
	returns whether this function can calculate the first derivative More...

bool	hasSecondDerivative () const
	returns whether this function can calculate the second derivative More...

bool	canProposeStartingPoint () const
	returns whether this function can propose a starting point. More...

bool	isConstrained () const
	returns whether this function can return More...

bool	hasConstraintHandler () const
	returns whether this function can return More...

bool	canProvideClosestFeasible () const
	Returns whether this function can calculate thee closest feasible to an infeasible point. More...

bool	isThreadSafe () const
	Returns true, when the function can be usd in parallel threads. More...

bool	isNoisy () const
	Returns true, when the function can be usd in parallel threads. More...

	AbstractObjectiveFunction ()
	Default ctor. More...

virtual	~AbstractObjectiveFunction ()
	Virtual destructor. More...

virtual void	init ()

void	setRng (random::rng_type *rng)
	Sets the Rng used by the objective function. More...

virtual std::size_t	numberOfObjectives () const

virtual bool	hasScalableObjectives () const

virtual void	setNumberOfObjectives (std::size_t numberOfObjectives)
	Adjusts the number of objectives if the function is scalable. More...

std::size_t	evaluationCounter () const
	Accesses the evaluation counter of the function. More...

AbstractConstraintHandler< SearchPointType > const &	getConstraintHandler () const
	Returns the constraint handler of the function if it has one. More...

virtual void	closestFeasible (SearchPointType &input) const
	If supported, the supplied point is repaired such that it satisfies all of the function's constraints. More...

ResultType	operator() (SearchPointType const &input) const
	Evaluates the function. Useful together with STL-Algorithms like std::transform. More...

virtual ResultType	evalDerivative (SearchPointType const &input, FirstOrderDerivative &derivative) const
	Evaluates the objective function and calculates its gradient. More...

virtual ResultType	evalDerivative (SearchPointType const &input, SecondOrderDerivative &derivative) const
	Evaluates the objective function and calculates its gradient. More...

Public Member Functions inherited from shark::INameable
virtual	~INameable ()

Additional Inherited Members
Public Types inherited from shark::AbstractObjectiveFunction< PointType, ResultT >
enum	Feature { HAS_VALUE = 1, HAS_FIRST_DERIVATIVE = 2, HAS_SECOND_DERIVATIVE = 4, CAN_PROPOSE_STARTING_POINT = 8, IS_CONSTRAINED_FEATURE = 16, HAS_CONSTRAINT_HANDLER = 32, CAN_PROVIDE_CLOSEST_FEASIBLE = 64, IS_THREAD_SAFE = 128, IS_NOISY = 256 }
	List of features that are supported by an implementation. More...

typedef PointType	SearchPointType

typedef ResultT	ResultType

typedef boost::mpl::if_< std::is_arithmetic< ResultT >, SearchPointType, RealMatrix >::type	FirstOrderDerivative

typedef TypedFlags< Feature >	Features
	This statement declares the member m_features. See Core/Flags.h for details. More...

typedef TypedFeatureNotAvailableException< Feature >	FeatureNotAvailableException

Protected Member Functions inherited from shark::AbstractObjectiveFunction< PointType, ResultT >
void	announceConstraintHandler (AbstractConstraintHandler< SearchPointType > const *handler)
	helper function which is called to announce the presence of an constraint handler. More...

Protected Attributes inherited from shark::AbstractObjectiveFunction< PointType, ResultT >
Features	m_features

std::size_t	m_evaluationCounter
	Evaluation counter, default value: 0. More...

AbstractConstraintHandler< SearchPointType > const *	m_constraintHandler

random::rng_type *	mep_rng

Detailed Description

Constrained Sphere function.

This is a simple sphere function minimizing \( f(x) = \sum_i^N x_i^2-m \) under the constraints that \( x_i \geq 1\) for \( i = 1,\dots,m \). The minimum is at \( x_1=\dots = x_m = 1\) and \( x_{m+1}=\dots = x_N = 0 \) with function value 0.

This is a simple benchmark for evolutionary algorithms as, the closer the algorithm is to the optimu

Definition at line 47 of file ConstrainedSphere.h.

Constructor & Destructor Documentation

◆ ConstrainedSphere()

shark::ConstrainedSphere::ConstrainedSphere	(	std::size_t	numberOfVariables = `5`,
		std::size_t	m = `1`
	)

inline

Definition at line 49 of file ConstrainedSphere.h.

References shark::AbstractObjectiveFunction< PointType, ResultT >::CAN_PROPOSE_STARTING_POINT, shark::AbstractObjectiveFunction< PointType, ResultT >::IS_CONSTRAINED_FEATURE, shark::AbstractObjectiveFunction< PointType, ResultT >::IS_THREAD_SAFE, and shark::AbstractObjectiveFunction< PointType, ResultT >::m_features.

Member Function Documentation

◆ eval()

double shark::ConstrainedSphere::eval ( const SearchPointType & input ) const

inlinevirtual

Evaluates the objective function for the supplied argument.

Parameters

[in] input The argument for which the function shall be evaluated.

Returns: The result of evaluating the function for the supplied argument.

Exceptions

FeatureNotAvailableException in the default implementation and if a function does not support this feature.

Reimplemented from shark::AbstractObjectiveFunction< PointType, ResultT >.

Definition at line 91 of file ConstrainedSphere.h.

References shark::AbstractObjectiveFunction< PointType, ResultT >::m_evaluationCounter.

◆ hasScalableDimensionality()

bool shark::ConstrainedSphere::hasScalableDimensionality ( ) const

inlinevirtual

Reimplemented from shark::AbstractObjectiveFunction< PointType, ResultT >.

Definition at line 64 of file ConstrainedSphere.h.

◆ isFeasible()

bool shark::ConstrainedSphere::isFeasible ( SearchPointType const & input ) const

inlinevirtual

Tests whether a point in SearchSpace is feasible, e.g., whether the constraints are fulfilled.

Parameters

[in] input The point to be tested for feasibility.

Returns: true if the point is feasible, false otherwise.

Reimplemented from shark::AbstractObjectiveFunction< PointType, ResultT >.

Definition at line 84 of file ConstrainedSphere.h.

◆ name()

std::string shark::ConstrainedSphere::name ( ) const

inlinevirtual

From INameable: return the class name.

Reimplemented from shark::INameable.

Definition at line 57 of file ConstrainedSphere.h.

◆ numberOfVariables()

std::size_t shark::ConstrainedSphere::numberOfVariables ( ) const

inlinevirtual

Accesses the number of variables.

Implements shark::AbstractObjectiveFunction< PointType, ResultT >.

Definition at line 60 of file ConstrainedSphere.h.

Referenced by proposeStartingPoint(), and setNumberOfVariables().

◆ proposeStartingPoint()

SearchPointType shark::ConstrainedSphere::proposeStartingPoint ( ) const

inlinevirtual

Proposes a starting point in the feasible search space of the function.

Returns: The generated starting point.

Exceptions

FeatureNotAvailableException in the default implementation and if a function does not support this feature.

Reimplemented from shark::AbstractObjectiveFunction< PointType, ResultT >.

Definition at line 72 of file ConstrainedSphere.h.

References shark::random::gauss(), shark::AbstractObjectiveFunction< PointType, ResultT >::mep_rng, and numberOfVariables().

◆ setNumberOfVariables()

void shark::ConstrainedSphere::setNumberOfVariables ( std::size_t numberOfVariables )

inlinevirtual

Adjusts the number of variables if the function is scalable.

Parameters

[in] numberOfVariables The new dimension.

Reimplemented from shark::AbstractObjectiveFunction< PointType, ResultT >.

Definition at line 68 of file ConstrainedSphere.h.

References numberOfVariables().

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

include/shark/ObjectiveFunctions/Benchmarks/ConstrainedSphere.h

Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ ConstrainedSphere()

Member Function Documentation

◆ eval()

◆ hasScalableDimensionality()

◆ isFeasible()

◆ name()

◆ numberOfVariables()

◆ proposeStartingPoint()

◆ setNumberOfVariables()