template<class Func>
class ROOT::Math::LSResidualFunc< Func >

LSResidualFunc class description.

Internal class used for accessing the residuals of the Least Square function and their derivatives which are estimated numerically using GSL numerical derivation. The class contains a pointer to the fit method function and an index specifying the i-th residual and wraps it in a multi-dim gradient function interface ROOT::Math::IGradientFunctionMultiDim. The class is used by ROOT::Math::GSLNLSMinimizer (GSL non linear least square fitter)

Definition at line 135 of file GSLNLSMinimizer.cxx.

Public Member Functions
	LSResidualFunc (const Func &func, unsigned int i)

	LSResidualFunc (const LSResidualFunc< Func > &rhs)

IMultiGenFunction *	Clone () const override
	Clone a function.

void	FdF (const double x, double &f, double g) const override
	Optimized method to evaluate at the same time the function value and derivative at a point x.

void	Gradient (const double x, double g) const override
	Evaluate all the vector of function derivatives (gradient) at a point x.

bool	IsLSType () const

unsigned int	NDim () const override
	Retrieve the dimension of the function.

LSResidualFunc< Func > &	operator= (const LSResidualFunc< Func > &rhs)

Public Member Functions inherited from ROOT::Math::IGradientFunctionMultiDimTempl< double >
bool	HasGradient () const override

bool	HasGradient () const override

Public Member Functions inherited from ROOT::Math::IBaseFunctionMultiDimTempl< double >
virtual	~IBaseFunctionMultiDimTempl ()=default

virtual	~IBaseFunctionMultiDimTempl ()=default

double	Derivative (const double x, unsigned int icoord, double previous_grad, double previous_g2, double previous_gstep) const
	In some cases, the derivative algorithm will use information from the previous step, these can be passed in with this overload.

double	Derivative (const double x, unsigned int icoord, double previous_grad, double previous_g2, double previous_gstep) const
	In some cases, the derivative algorithm will use information from the previous step, these can be passed in with this overload.

double	Derivative (const double *x, unsigned int icoord=0) const
	Return the partial derivative with respect to the passed coordinate.

double	Derivative (const double *x, unsigned int icoord=0) const
	Return the partial derivative with respect to the passed coordinate.

double	operator() (const double *x) const
	Evaluate the function at a point x[].

double	operator() (const double *x) const
	Evaluate the function at a point x[].

Private Member Functions
double	DoDerivative (const double *, unsigned int) const override
	Function to evaluate the derivative with respect each coordinate. To be implemented by the derived class.

double	DoEval (const double *x) const override
	Implementation of the evaluation function. Must be implemented by derived classes.

Private Attributes
const Func *	fChi2

unsigned int	fIndex

Additional Inherited Members
Public Types inherited from ROOT::Math::IBaseFunctionMultiDimTempl< double >
typedef double	BackendType

typedef IBaseFunctionMultiDimTempl< double >	BaseFunc

Inheritance diagram for ROOT::Math::LSResidualFunc< Func >:

[legend]

Constructor & Destructor Documentation

◆ LSResidualFunc() [1/2]

template<class Func>

ROOT::Math::LSResidualFunc< Func >::LSResidualFunc	(	const Func &	func,
		unsigned int	i )

inline

Definition at line 137 of file GSLNLSMinimizer.cxx.

◆ LSResidualFunc() [2/2]

template<class Func>

ROOT::Math::LSResidualFunc< Func >::LSResidualFunc ( const LSResidualFunc< Func > & rhs )

inline

Definition at line 140 of file GSLNLSMinimizer.cxx.

Member Function Documentation

◆ Clone()

template<class Func>

IMultiGenFunction * ROOT::Math::LSResidualFunc< Func >::Clone ( ) const

inlineoverridevirtual

Clone a function.

Each derived class must implement their version of the Clone method.

Implements ROOT::Math::IBaseFunctionMultiDimTempl< double >.

Definition at line 150 of file GSLNLSMinimizer.cxx.

◆ DoDerivative()

template<class Func>

double ROOT::Math::LSResidualFunc< Func >::DoDerivative	(	const double *	,
		unsigned int	) const

inlineoverrideprivatevirtual

Function to evaluate the derivative with respect each coordinate. To be implemented by the derived class.

Reimplemented from ROOT::Math::IBaseFunctionMultiDimTempl< double >.

Definition at line 167 of file GSLNLSMinimizer.cxx.

◆ DoEval()

template<class Func>

double ROOT::Math::LSResidualFunc< Func >::DoEval ( const double * x ) const

inlineoverrideprivatevirtual

Implementation of the evaluation function. Must be implemented by derived classes.

Implements ROOT::Math::IBaseFunctionMultiDimTempl< double >.

Definition at line 165 of file GSLNLSMinimizer.cxx.

◆ FdF()

template<class Func>

void ROOT::Math::LSResidualFunc< Func >::FdF	(	const double *	x,
		double &	f,
		double *	df ) const

inlineoverridevirtual

Optimized method to evaluate at the same time the function value and derivative at a point x.

Often both value and derivatives are needed and it is often more efficient to compute them at the same time. Derived class should implement this method if performances play an important role and if it is faster to evaluate value and derivative at the same time

Reimplemented from ROOT::Math::IBaseFunctionMultiDimTempl< double >.

Definition at line 162 of file GSLNLSMinimizer.cxx.

◆ Gradient()

template<class Func>

void ROOT::Math::LSResidualFunc< Func >::Gradient	(	const double *	x,
		double *	grad ) const

inlineoverridevirtual

Evaluate all the vector of function derivatives (gradient) at a point x.

Derived classes must re-implement it if more efficient than evaluating one at a time

Reimplemented from ROOT::Math::IBaseFunctionMultiDimTempl< double >.

Definition at line 154 of file GSLNLSMinimizer.cxx.

◆ IsLSType()

template<class Func>

bool ROOT::Math::LSResidualFunc< Func >::IsLSType ( ) const

inline

Definition at line 160 of file GSLNLSMinimizer.cxx.

◆ NDim()

template<class Func>

unsigned int ROOT::Math::LSResidualFunc< Func >::NDim ( ) const

inlineoverridevirtual

Retrieve the dimension of the function.

Implements ROOT::Math::IBaseFunctionMultiDimTempl< double >.

Definition at line 152 of file GSLNLSMinimizer.cxx.

◆ operator=()

template<class Func>

LSResidualFunc< Func > & ROOT::Math::LSResidualFunc< Func >::operator= ( const LSResidualFunc< Func > & rhs )

inline

Definition at line 143 of file GSLNLSMinimizer.cxx.

Member Data Documentation

◆ fChi2

template<class Func>

const Func* ROOT::Math::LSResidualFunc< Func >::fChi2

private

Definition at line 175 of file GSLNLSMinimizer.cxx.

◆ fIndex

template<class Func>

unsigned int ROOT::Math::LSResidualFunc< Func >::fIndex

private

Definition at line 174 of file GSLNLSMinimizer.cxx.

math/mathmore/src/GSLNLSMinimizer.cxx

Public Member Functions

Private Member Functions

Private Attributes

Additional Inherited Members

Constructor & Destructor Documentation

◆ LSResidualFunc() [1/2]

◆ LSResidualFunc() [2/2]

Member Function Documentation

◆ Clone()

◆ DoDerivative()

◆ DoEval()

◆ FdF()

◆ Gradient()

◆ IsLSType()

◆ NDim()

◆ operator=()

Member Data Documentation

◆ fChi2

◆ fIndex