Herwig::GaussianIntegrator Class Reference

#include <GaussianIntegrator.h>

Inheritance diagram for Herwig::GaussianIntegrator:

Standard constructors and destructors.
template<class T >
using	ValT = decltype(std::declval< typename T::ValType >() *std::declval< typename T::ArgType >())
	helper type for the integration result
std::vector< std::vector< double > >	_weights
	The weights for the gaussian quadrature.
std::vector< std::vector< double > >	_abscissae
	The abscissae.
double	_abserr
	The parameters controlling the error.
double	_relerr
double	_binwidth
	The minimum width of a bin as a fraction of the integration region.
int	_maxeval
	Maximum number of function evaluations.
	GaussianIntegrator ()
	Default Constructor.
	GaussianIntegrator (double abserr, double relerr, double binwidth, int maxeval)
	Specify all the parameters.
template<class T >
ValT< T >	value (const T &, const typename T::ArgType lower, const typename T::ArgType upper) const
	The value of the integral.
GaussianIntegrator &	operator= (const GaussianIntegrator &)=delete
	The assignment operator is private and must never be called.
void	Init ()
	Initialise the weights and abscissae.

Additional Inherited Members
Public Types inherited from ThePEG::Pointer::ReferenceCounted
typedef unsigned int	CounterType
Public Member Functions inherited from ThePEG::Pointer::ReferenceCounted
CounterType	referenceCount () const
Public Attributes inherited from ThePEG::Pointer::ReferenceCounted
const unsigned long	uniqueId
Protected Member Functions inherited from ThePEG::Pointer::ReferenceCounted
	ReferenceCounted (const ReferenceCounted &)
ReferenceCounted &	operator= (const ReferenceCounted &)

Detailed Description

Author

Peter Richardson
This class is designed to perform the integral of a function using Gaussian quadrature.The method is adaptive based on using 6th,12th, 24th,48th, or 96th order Gaussian quadrature combined with subdivision of the integral if this is insufficient.

The class is templated on a simple class which should provide a T::operator () (double) const which provides the integrand for the function.

Definition at line 33 of file GaussianIntegrator.h.

Member Typedef Documentation

ValT

template<class T >

using Herwig::GaussianIntegrator::ValT = decltype(std::declval<typename T::ValType>() * std::declval<typename T::ArgType>())

helper type for the integration result

Definition at line 66 of file GaussianIntegrator.h.

Constructor & Destructor Documentation

GaussianIntegrator() [1/2]

Herwig::GaussianIntegrator::GaussianIntegrator ( )

inline

Default Constructor.

Definition at line 42 of file GaussianIntegrator.h.

References Init().

GaussianIntegrator() [2/2]

Herwig::GaussianIntegrator::GaussianIntegrator ( double  abserr, double  relerr, double  binwidth, int  maxeval  )

inline

Specify all the parameters.

Parameters

abserr	Absolute error.
relerr	Relative error.
binwidth	Width of the bin as a fraction of the integration region.
maxeval	Maximum number of function evaluations

Definition at line 55 of file GaussianIntegrator.h.

References Init().

Member Function Documentation

operator=()

GaussianIntegrator & Herwig::GaussianIntegrator::operator= ( const GaussianIntegrator &  )

privatedelete

The assignment operator is private and must never be called.

In fact, it should not even be implemented.

value()

template<class T >

ValT< T > Herwig::GaussianIntegrator::value ( const T &  , const typename T::ArgType  lower, const typename T::ArgType  upper  ) const

inline

The value of the integral.

Parameters

lower	The lower limit of integration.
upper	The upper limit of integration.

Member Data Documentation

_abscissae

std::vector< std::vector <double> > Herwig::GaussianIntegrator::_abscissae

private

The abscissae.

Definition at line 102 of file GaussianIntegrator.h.

_abserr

double Herwig::GaussianIntegrator::_abserr

private

The parameters controlling the error.

Definition at line 107 of file GaussianIntegrator.h.

_binwidth

double Herwig::GaussianIntegrator::_binwidth

private

The minimum width of a bin as a fraction of the integration region.

Definition at line 112 of file GaussianIntegrator.h.

_maxeval

int Herwig::GaussianIntegrator::_maxeval

private

Maximum number of function evaluations.

Definition at line 117 of file GaussianIntegrator.h.

_relerr

double Herwig::GaussianIntegrator::_relerr

private

Definition at line 107 of file GaussianIntegrator.h.

_weights

std::vector< std::vector<double> > Herwig::GaussianIntegrator::_weights

private

The weights for the gaussian quadrature.

Definition at line 97 of file GaussianIntegrator.h.

---

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

• GaussianIntegrator.h