Base class for all one-dimensional functions that can be fitted. More...

#include <Functions.h>

Inheritance diagram for atomicrex::FunctionBase:

Public Types
enum	NormalizationMode { NONE, SPHERICAL_INTEGRAL, UNITY_ORIGIN }

Public Member Functions
	FunctionBase (const FPString &id, FitJob *job, const FPString &tag=FPString())
	Constructor.

bool	hasCutoff () const
	Returns whether this function has a cutoff.

double	cutoff () const

void	setCutoff (double cutoff)

double	prefactor () const
	Returns the constant prefactor the function is multiplied with.

double	evaluate (double r)
	Evaluates the function at the given r and multiplies the value with the proper normalization factor.

double	evaluate (double r, double &deriv)
	Evaluates the function and its derivative at the given r and multiplies the values with the proper normalization factor.

void	writeTabulated (std::ostream &out, double rmin, double rmax, double dr)
	Write tabulated function to stream for visualization with Gnuplot. More...

NormalizationMode	normalizationMode () const
	Returns the normalization mode set for this function.

void	setNormalizationMode (NormalizationMode mode)
	Specifies the normalization mode to be used for this function.

void	computePrefactor ()

virtual void	dofValueChanged (DegreeOfFreedom &dof) override

const std::shared_ptr< FunctionBase > &	screeningFunction () const
	Returns the screening function applied to this function, or NULL.

void	setScreeningFunction (const std::shared_ptr< FunctionBase > &func)

void	verifyDerivative ()

void	checkDerivativeNumerically (double r)

double	centralDerivative (double r, double h, double &abserr_trunc, double &abserr_round)

virtual void	parse (XML::Element functionElement) override
	Parses function parameters from the given XML element.

virtual XML::OElement	generateXMLDefinition (const FPString &elementName)
	Produces an XML representation of the function's current parameters and DOFs.

Public Member Functions inherited from atomicrex::FitObject
virtual	~FitObject ()=default
	Virtual destructor.

double	relativeWeight () const
	Returns the relative fit weight assigned to this object.

void	setRelativeWeight (double weight)
	Assigns a relative fit weight to this object.

virtual void	assignAbsoluteWeights (double absoluteWeight)
	Recursively assigns absolute weights to the properties of this object and its sub-objects.

virtual bool	computeProperties (bool isFitting)
	Computes all enabled properties of the object.

const std::vector< FitProperty * > &	properties () const
	Returns a list of fitting properties of this object.

void	listAllProperties (std::vector< FitProperty *> &list) const
	Builds a list of properties of this object and all its sub-objects.

FitProperty *	propertyById (const FPString &id) const
	Returns the property with the given ID.

const std::vector< DegreeOfFreedom * > &	DOF () const
	Returns a list of degrees of freedom of this object.

void	listAllDOF (std::vector< DegreeOfFreedom *> &list) const
	Builds a list of degrees of freedom of this object and all its sub-objects.

DegreeOfFreedom *	DOFById (const FPString &id, const FPString &tag=FPString()) const
	Returns the degree of freedom with the given ID (and tag).

const std::vector< FitObject * > &	fitObjects () const
	Returns the list of FitObjects which are part of this group.

void	registerSubObject (FitObject *subobject, bool deleteOnShutdown=false)
	Registers a sub-object.

virtual void	print (MsgLogger &stream)
	Outputs the name of the object.

bool	fitEnabled () const
	Returns whether this object and it's children are included in the fit.

void	setFitEnabled (bool enable)
	Sets whether this object and it's children are included in the fit.

bool	outputEnabled () const

void	setOutputEnabled (bool enable)

const FPString &	id () const
	Returns the identifier of this object instance.

void	setId (const FPString &id)
	Sets the main identification tag.

const FPString &	tag () const
	Returns the assigned tag string.

void	setTag (const FPString &tag)
	Sets the complementary identification tag.

FitJob *	job () const
	Returns a pointer to the job to which this object belongs.

FitObject *	parent () const
	Returns the parent of this object in the hierarchy.

Public Member Functions inherited from atomicrex::NumericalIntegration
template<typename DifferentialForm >
double	integrate (double a, double b, DifferentialForm diffForm)

virtual double	integrate (double a, double b)

virtual double	integrateSpherical (double a, double b)

Static Public Member Functions
static std::shared_ptr< FunctionBase >	createAndParse (XML::Element functionElement, const FPString &id, FitJob *job)
	Parses an XML element and creates a function object out of it.

Protected Member Functions
virtual double	evaluateInternal (double r) override=0

virtual double	evaluateInternal (double r, double &deriv)=0

virtual std::vector< DegreeOfFreedom * >	DOFToExport ()

Protected Member Functions inherited from atomicrex::FitObject
	FitObject ()
	Default Constructor.

	FitObject (const FPString &id, FitJob *job, const FPString &tag=FPString())
	Constructor.

void	registerProperty (FitProperty *prop, bool deleteOnShutdown=false)
	Registers a property of this object.

void	registerDOF (DegreeOfFreedom *dof)
	Registers a DOF of this object.

Protected Attributes
double	_cutoff
	The function cutoff.

double	_prefactor
	The constant prefactor used to normalize the function.

NormalizationMode	_normalizationMode
	Controls the type of normalization applied to the function.

std::shared_ptr< FunctionBase >	_screeningFunction
	Optional screening function.

Protected Attributes inherited from atomicrex::FitObject
bool	_fitEnabled = true
	Controls whether this object and it's children are included in the fit.

bool	_outputEnabled = true

FitJob *	_job = nullptr
	Pointer to the job this object belongs to.

FPString	_id
	The identifier string of this object instance.

double	_relativeWeight = 1.0
	The relative fit weight assigned to this object.

Detailed Description

Base class for all one-dimensional functions that can be fitted.

Optionally, a function can be normalized by multiplying it with a constant pre-factor, and a screening function can be imposed.

Member Enumeration Documentation

◆ NormalizationMode

enum atomicrex::FunctionBase::NormalizationMode

Enumerator
NONE	Do not perform any normalization; use unmodified function.
SPHERICAL_INTEGRAL	Spherical integral over [0,cutoff] is unity, $\int dx f(x) = 1$ .
UNITY_ORIGIN	Function is one at origin, .

Member Function Documentation

◆ centralDerivative()

double atomicrex::FunctionBase::centralDerivative	(	double	r,
		double	h,
		double &	abserr_trunc,
		double &	abserr_round
	)

Compute the numerical derivative at the given r using the 5-point rule ( $-h$ , $-h/2$ , $0$ , $+h/2$ , $+h$ ). Note that the value at the central point is not used.

◆ checkDerivativeNumerically()

void atomicrex::FunctionBase::checkDerivativeNumerically ( double r )

Performs a validation of the analytical derivative by comparing it to a numerically computed derivative at the given r. Throws an exception if the analytical derivative does not match.

◆ computePrefactor()

void atomicrex::FunctionBase::computePrefactor ( )

Normalizes the function by computing the constant prefactor. This function is called once every time the parameters of the function have changed.

◆ cutoff()

double atomicrex::FunctionBase::cutoff ( ) const

inline

Returns the cutoff of this function. The function will evaluate to flat zero for positions beyond this cutoff.

◆ DOFToExport()

virtual std::vector<DegreeOfFreedom*> atomicrex::FunctionBase::DOFToExport ( )

inlineprotectedvirtual

Returns the list of DOFs that should be exported as part of the <fit-dof> element. By default, all DOFs of the function are exported in this way. Subclasses may override this method to implement custom output formats for certain DOFs.

Reimplemented in atomicrex::FunctionSpline, and atomicrex::FunctionPoly.

◆ dofValueChanged()

virtual void atomicrex::FunctionBase::dofValueChanged ( DegreeOfFreedom & dof )

inlineoverridevirtual

This function is called by the DOFs of this object each time their value changes. Setting the prefactor to zero will trigger its recalculation next time evaluateNormalized() is called.

Reimplemented from atomicrex::FitObject.

Reimplemented in atomicrex::FunctionSpline, atomicrex::FunctionPoly, and atomicrex::ParsedFunction.

◆ evaluateInternal() [1/2]

virtual double atomicrex::FunctionBase::evaluateInternal ( double r )

overrideprotectedpure virtual

Evaluates the function at the given r. This does not include the constant pre-factor, or the optional screening function.

Implements atomicrex::NumericalIntegration.

Implemented in atomicrex::FunctionProduct, atomicrex::FunctionConstant, atomicrex::FunctionSum, atomicrex::FunctionInverseArgument, atomicrex::FunctionSpline, atomicrex::FunctionPoly, atomicrex::FunctionMorseC, atomicrex::FunctionMorseB, atomicrex::FunctionMorseA, atomicrex::FunctionExpGaussian, atomicrex::FunctionExpB, atomicrex::FunctionExpA, and atomicrex::ParsedFunction.

◆ evaluateInternal() [2/2]

virtual double atomicrex::FunctionBase::evaluateInternal	(	double	r,
		double &	deriv
	)

protectedpure virtual

Evaluates the function and its derivative at the given r. This does not include the constant pre-factor, or the optional screening function.

Implemented in atomicrex::FunctionProduct, atomicrex::FunctionConstant, atomicrex::FunctionSum, atomicrex::FunctionInverseArgument, atomicrex::FunctionSpline, atomicrex::FunctionPoly, atomicrex::FunctionMorseC, atomicrex::FunctionMorseB, atomicrex::FunctionMorseA, atomicrex::FunctionExpGaussian, atomicrex::FunctionExpB, atomicrex::FunctionExpA, and atomicrex::ParsedFunction.

◆ setCutoff()

void atomicrex::FunctionBase::setCutoff ( double cutoff )

inline

Sets the cutoff of this function. The function will evaluate to flat zero for positions beyond this cutoff.

◆ setScreeningFunction()

void atomicrex::FunctionBase::setScreeningFunction ( const std::shared_ptr< FunctionBase > & func )

inline

Applies the given screening function to this function. This function becomes the owner of the screening function and will delete it when done.

◆ verifyDerivative()

void atomicrex::FunctionBase::verifyDerivative ( )

Makes sure that the analytical first derivative is correct by comparing its value at various point to the numeric first derivative.

◆ writeTabulated()

void atomicrex::FunctionBase::writeTabulated	(	std::ostream &	out,
		double	rmin,
		double	rmax,
		double	dr
	)

Write tabulated function to stream for visualization with Gnuplot.

Parameters

out[in]	output stream
rmin[in]	lower limit of range for input variable
rmax[in]	upper limit of range for input variable
dr[in]	spacing of input variable

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

Functions.h
Functions.cpp

Public Types

Public Member Functions

Static Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Member Enumeration Documentation

◆ NormalizationMode

Member Function Documentation

◆ centralDerivative()

◆ checkDerivativeNumerically()

◆ computePrefactor()

◆ cutoff()

◆ DOFToExport()

◆ dofValueChanged()

◆ evaluateInternal() [1/2]

◆ evaluateInternal() [2/2]

◆ setCutoff()

◆ setScreeningFunction()

◆ verifyDerivative()

◆ writeTabulated()