Interface (abstract class) for one-dimensional functions providing a gradient calculation.

The method ROOT::Math::IFunction::Derivative calculates the derivative and ROOT::Math::Fdf calculates the derivative and the function values at the same time. The pure private virtual method DoDerivative() must be implemented by the derived classes, while FdF is by default implemented using DoDerivative, but it can be overloaded by the derived classes to improve the efficiency in the derivative calculation.

Specialized Gradient interface(abstract class) for one dimensional functions It provides a method to evaluate the derivative of the function, Derivative and a method to evaluate at the same time the function and the derivative FdF

Definition at line 275 of file IFunction.h.

Public Member Functions
bool	HasGradient () const override

Public Member Functions inherited from ROOT::Math::IBaseFunctionOneDim
virtual	~IBaseFunctionOneDim ()=default

virtual IBaseFunctionOneDim *	Clone () const =0
	Clone a function.

double	Derivative (const double *x) const
	Compatibility method with multi-dimensional interface for partial derivative.

double	Derivative (double x) const
	Return the derivative of the function at a point x Use the private method DoDerivative.

void	FdF (const double x, double &f, double df) const
	Compatibility method with multi-dimensional interface for Gradient and function evaluation.

virtual void	FdF (double x, double &f, double &df) const
	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
	Compatibility method with multi-dimensional interface for Gradient.

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

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