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ROOT::Fit::FcnAdapter Class Reference

Definition at line 27 of file FcnAdapter.h.

Public Types

typedef double BackendType
typedef IBaseFunctionMultiDimTempl< doubleBaseFunc

Public Member Functions

 FcnAdapter (void(*fcn)(int &, double *, double &, double *, int), int dim=0)
 ~FcnAdapter () override
ROOT::Math::IMultiGenFunctionClone () const override
 Clone a function.
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.
virtual void FdF (const double *x, double &f, double *df) const
 Optimized method to evaluate at the same time the function value and derivative at a point x.
virtual void Gradient (const double *x, double *grad) const
 Evaluate all the vector of function derivatives (gradient) at a point x.
virtual bool HasGradient () const
unsigned int NDim () const override
 Retrieve the dimension of the function.
double operator() (const double *x) const
 Evaluate the function at a point x[].
void SetDimension (int dim)

Private Member Functions

virtual double DoDerivative (const double *, unsigned int) const
 Function to evaluate the derivative with respect each coordinate. To be implemented by the derived class.
virtual double DoDerivativeWithPrevResult (const double *x, unsigned int icoord, double *, double *, double *) const
 In some cases, the derivative algorithm will use information from the previous step, these can be passed in with this overload.
double DoEval (const double *x) const override
 Implementation of the evaluation function. Must be implemented by derived classes.

Private Attributes

unsigned int fDim
void(* fFCN )(int &, double *, double &, double *, int)

#include <Fit/FcnAdapter.h>

Inheritance diagram for ROOT::Fit::FcnAdapter:
ROOT::Math::IBaseFunctionMultiDimTempl< double >

Member Typedef Documentation

◆ BackendType

typedef double ROOT::Math::IBaseFunctionMultiDimTempl< double >::BackendType
inherited

Definition at line 67 of file IFunction.h.

◆ BaseFunc

typedef IBaseFunctionMultiDimTempl<double> ROOT::Math::IBaseFunctionMultiDimTempl< double >::BaseFunc
inherited

Definition at line 68 of file IFunction.h.

Constructor & Destructor Documentation

◆ FcnAdapter()

ROOT::Fit::FcnAdapter::FcnAdapter ( void(* fcn )(int &, double *, double &, double *, int),
int dim = 0 )
inline

Definition at line 31 of file FcnAdapter.h.

◆ ~FcnAdapter()

ROOT::Fit::FcnAdapter::~FcnAdapter ( )
inlineoverride

Definition at line 36 of file FcnAdapter.h.

Member Function Documentation

◆ Clone()

ROOT::Math::IMultiGenFunction * ROOT::Fit::FcnAdapter::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 40 of file FcnAdapter.h.

◆ Derivative() [1/2]

double ROOT::Math::IBaseFunctionMultiDimTempl< double >::Derivative ( const double * x,
unsigned int icoord,
double * previous_grad,
double * previous_g2,
double * previous_gstep ) const
inlineinherited

In some cases, the derivative algorithm will use information from the previous step, these can be passed in with this overload.

The previous_* arrays can also be used to return second derivative and step size so that these can be passed forward again as well at the call site, if necessary.

Definition at line 120 of file IFunction.h.

◆ Derivative() [2/2]

double ROOT::Math::IBaseFunctionMultiDimTempl< double >::Derivative ( const double * x,
unsigned int icoord = 0 ) const
inlineinherited

Return the partial derivative with respect to the passed coordinate.

Definition at line 115 of file IFunction.h.

◆ DoDerivative()

virtual double ROOT::Math::IBaseFunctionMultiDimTempl< double >::DoDerivative ( const double * ,
unsigned int  ) const
inlineprivatevirtualinherited

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

Reimplemented in ROOT::Math::GradFunctor, ROOT::Math::LSResidualFunc< Func >, ROOT::Math::MinimTransformFunction, and ROOT::Math::MultiNumGradFunction.

Definition at line 131 of file IFunction.h.

◆ DoDerivativeWithPrevResult()

virtual double ROOT::Math::IBaseFunctionMultiDimTempl< double >::DoDerivativeWithPrevResult ( const double * x,
unsigned int icoord,
double * ,
double * ,
double *  ) const
inlineprivatevirtualinherited

In some cases, the derivative algorithm will use information from the previous step, these can be passed in with this overload.

The previous_* arrays can also be used to return second derivative and step size so that these can be passed forward again as well at the call site, if necessary.

Definition at line 136 of file IFunction.h.

◆ DoEval()

double ROOT::Fit::FcnAdapter::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 48 of file FcnAdapter.h.

◆ FdF()

virtual void ROOT::Math::IBaseFunctionMultiDimTempl< double >::FdF ( const double * x,
double & f,
double * df ) const
inlinevirtualinherited

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 in ROOT::Math::LSResidualFunc< Func >.

Definition at line 108 of file IFunction.h.

◆ Gradient()

virtual void ROOT::Math::IBaseFunctionMultiDimTempl< double >::Gradient ( const double * x,
double * grad ) const
inlinevirtualinherited

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 in ROOT::Math::GradFunctor, and ROOT::Math::LSResidualFunc< Func >.

Definition at line 96 of file IFunction.h.

◆ HasGradient()

virtual bool ROOT::Math::IBaseFunctionMultiDimTempl< double >::HasGradient ( ) const
inlinevirtualinherited

Reimplemented in ROOT::Math::IGradientFunctionMultiDimTempl< double >.

Definition at line 92 of file IFunction.h.

◆ NDim()

unsigned int ROOT::Fit::FcnAdapter::NDim ( ) const
inlineoverridevirtual

Retrieve the dimension of the function.

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

Definition at line 38 of file FcnAdapter.h.

◆ operator()()

double ROOT::Math::IBaseFunctionMultiDimTempl< double >::operator() ( const double * x) const
inlineinherited

Evaluate the function at a point x[].

Use the pure virtual private method DoEval which must be implemented by the sub-classes.

Definition at line 81 of file IFunction.h.

◆ SetDimension()

void ROOT::Fit::FcnAdapter::SetDimension ( int dim)
inline

Definition at line 44 of file FcnAdapter.h.

Member Data Documentation

◆ fDim

unsigned int ROOT::Fit::FcnAdapter::fDim
private

Definition at line 58 of file FcnAdapter.h.

◆ fFCN

void(* ROOT::Fit::FcnAdapter::fFCN) (int &, double *, double &, double *, int)
private

Definition at line 59 of file FcnAdapter.h.


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