The Interpolator class is a mother class for the x-space interpolationand requires the implementation of a specialized interpolation algorithm. The current version uses the joint grid object stored allocated by the Grid class. More...

#include <interpolator.h>

Inheritance diagram for apfel::Interpolator:

Public Member Functions
virtual	~Interpolator ()=default

	Interpolator (Grid const &gr)
	The Interpolator constructor.

	Interpolator (Grid const &gr, std::vector< std::vector< double > > const &distsubgrid, std::vector< double > const &distjointgrid)
	The Interpolator constructor.

virtual double	InterpolantLog (int const &beta, double const &lnx, SubGrid const &sg) const =0
	Pure virtual method for the interpolating functions polynomial in log(x).

virtual double	Interpolant (int const &beta, double const &x, SubGrid const &sg) const =0
	Pure virtual method for the interpolating functions.

virtual double	DerInterpolant (int const &, double const &, SubGrid const &) const
	Virtual method for the derivative of the interpolating functions.

virtual double	IntInterpolant (int const &, double const &, double const &, SubGrid const &) const
	Virtual method for the integral of the interpolating functions.

virtual std::array< int, 2 >	SumBounds (double const &x, SubGrid const &sg) const =0
	This purely virtual function computes the lower and upper bounds on which the the sum over interpolants is limited.

Evaluate functions
List of functions that perform the interpolation on the x-space grid. These also include the derivative and the integral of the interpolated function.
double	Evaluate (double const &x) const
	Function that evaluates the interpolated function on the joint grid.

double	Evaluate (double const &x, int const &ig) const
	Function that evaluates the interpolated function on a given subgrid.

double	Derive (double const &x) const
	Function that evaluates the derivative of the interpolated function on the joint grid.

double	Integrate (double const &a, double const &b) const
	Function that evaluates the integral of the interpolated function in the interval [a,b] on the joint grid.

Getters
Grid const &	GetGrid () const
	The grid.

std::vector< std::vector< double > > const &	GetDistributionSubGrid () const
	The distribution on the subgrids.

std::vector< double > const &	GetDistributionJointGrid () const
	The distribution on the joint grid.

void	Print () const
	Print the Interpolator object.

Protected Attributes
Grid const &	_grid
	The stored grid reference.

std::vector< std::vector< double > >	_distributionSubGrid
	The array with the distribution values on the subgrid.

std::vector< double >	_distributionJointGrid
	The array with the distribution values on the joint grid.

Friends
std::ostream &	operator<< (std::ostream &os, Interpolator const &sg)
	Method which prints Interpolator with cout <<. This only prints the first subgrid and is supposed to be used for debugging purposes.

Detailed Description

The Interpolator class is a mother class for the x-space interpolationand requires the implementation of a specialized interpolation algorithm. The current version uses the joint grid object stored allocated by the Grid class.

Constructor & Destructor Documentation

◆ ~Interpolator()

virtual apfel::Interpolator::~Interpolator ( )

virtualdefault

◆ Interpolator() [1/2]

apfel::Interpolator::Interpolator ( Grid const & gr )

The Interpolator constructor.

Parameters

gr	the x-space grid object over which interpolation takes place

◆ Interpolator() [2/2]

apfel::Interpolator::Interpolator	(	Grid const &	gr,
		std::vector< std::vector< double > > const &	distsubgrid,
		std::vector< double > const &	distjointgrid )

The Interpolator constructor.

Parameters

gr	the x-space grid object over which interpolation takes place
distsubgrid	the vector of subgrids
distjointgrid	the joint subgrid

Note: distjointgrid and distsubgrid are assumed to match the structure of the grid gr.

Member Function Documentation

◆ DerInterpolant()

virtual double apfel::Interpolator::DerInterpolant	(	int const &	,
		double const &	,
		SubGrid const &	) const

inlinevirtual

Virtual method for the derivative of the interpolating functions.

Returns: the derivarive of the interpolation weights

Reimplemented in apfel::LagrangeInterpolator.

◆ Derive()

double apfel::Interpolator::Derive ( double const & x ) const

Function that evaluates the derivative of the interpolated function on the joint grid.

Parameters

x	the value in x where the derivative has to be computed

Returns: the derivative of the interpolated function

Examples: qgriddist_test.cc.

◆ Evaluate() [1/2]

double apfel::Interpolator::Evaluate ( double const & x ) const

Function that evaluates the interpolated function on the joint grid.

Parameters

x	the value in x to be interpolated

Returns: the interpolated result

Examples: distribution_test.cc, massiveCF_test.cc, principal_value_test.cc, qgriddist_test.cc, structurefunction_cc_test.cc, structurefunction_massive_test.cc, structurefunction_nc_pol_test.cc, and structurefunction_nc_test.cc.

◆ Evaluate() [2/2]

double apfel::Interpolator::Evaluate	(	double const &	x,
		int const &	ig ) const

Function that evaluates the interpolated function on a given subgrid.

Parameters

x	the value in x to be interpolated
ig	the subgrid index

Returns: the interpolated result

◆ GetDistributionJointGrid()

std::vector< double > const & apfel::Interpolator::GetDistributionJointGrid ( ) const

inline

The distribution on the joint grid.

◆ GetDistributionSubGrid()

std::vector< std::vector< double > > const & apfel::Interpolator::GetDistributionSubGrid ( ) const

inline

The distribution on the subgrids.

◆ GetGrid()

Grid const & apfel::Interpolator::GetGrid ( ) const

inline

The grid.

◆ Integrate()

double apfel::Interpolator::Integrate	(	double const &	a,
		double const &	b ) const

Function that evaluates the integral of the interpolated function in the interval [a,b] on the joint grid.

Parameters

a	the lower integration bound
b	the upper integration bound

Returns: the integral of the interpolated function

Examples: qgriddist_test.cc.

◆ Interpolant()

virtual double apfel::Interpolator::Interpolant	(	int const &	beta,
		double const &	x,
		SubGrid const &	sg ) const

pure virtual

Pure virtual method for the interpolating functions.

Parameters

beta	the x-space grid index
x	the value of the interpolation point
sg	the SubGrid over which the interpolant is defined

Returns: the interpolation weights

Implemented in apfel::LagrangeInterpolator.

◆ InterpolantLog()

virtual double apfel::Interpolator::InterpolantLog	(	int const &	beta,
		double const &	lnx,
		SubGrid const &	sg ) const

pure virtual

Pure virtual method for the interpolating functions polynomial in log(x).

Parameters

beta	the x-space grid index
lnx	the value (of the log) of the interpolation point
sg	the SubGrid over which the interpolant is defined

Returns: the interpolation weights

Note: This interpolant is polynomial in log(x) and is used when computing operators on the grid. The reason is it's translation invariance on a logarithmically spaced grid that reduces the ammount of computations.

Implemented in apfel::LagrangeInterpolator.

◆ IntInterpolant()

virtual double apfel::Interpolator::IntInterpolant	(	int const &	,
		double const &	,
		double const &	,
		SubGrid const &	) const

inlinevirtual

Virtual method for the integral of the interpolating functions.

Returns: the integral of the interpolation weights

Reimplemented in apfel::LagrangeInterpolator.

◆ Print()

void apfel::Interpolator::Print ( ) const

inline

Print the Interpolator object.

◆ SumBounds()

virtual std::array< int, 2 > apfel::Interpolator::SumBounds	(	double const &	x,
		SubGrid const &	sg ) const

pure virtual

This purely virtual function computes the lower and upper bounds on which the the sum over interpolants is limited.

Parameters

x	the value in x to be interpolated
sg	the SubGrid over which the interpolant is defined

Returns: the lower and upper bounds of the grid index

Implemented in apfel::LagrangeInterpolator.

Friends And Related Symbol Documentation

◆ operator<<

std::ostream & operator<<	(	std::ostream &	os,
		Interpolator const &	sg )

friend

Method which prints Interpolator with cout <<. This only prints the first subgrid and is supposed to be used for debugging purposes.

Member Data Documentation

◆ _distributionJointGrid

std::vector<double> apfel::Interpolator::_distributionJointGrid

protected

The array with the distribution values on the joint grid.

◆ _distributionSubGrid

std::vector<std::vector<double> > apfel::Interpolator::_distributionSubGrid

protected

The array with the distribution values on the subgrid.

◆ _grid

Grid const& apfel::Interpolator::_grid

protected

The stored grid reference.

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

/Users/vb262523/Codes/apfelxx/inc/apfel/interpolator.h

Public Member Functions

Protected Attributes

Friends

Detailed Description

Constructor & Destructor Documentation

◆ ~Interpolator()

◆ Interpolator() [1/2]

◆ Interpolator() [2/2]

Member Function Documentation

◆ DerInterpolant()

◆ Derive()

◆ Evaluate() [1/2]

◆ Evaluate() [2/2]

◆ GetDistributionJointGrid()

◆ GetDistributionSubGrid()

◆ GetGrid()

◆ Integrate()

◆ Interpolant()

◆ InterpolantLog()

◆ IntInterpolant()

◆ Print()

◆ SumBounds()

Friends And Related Symbol Documentation

◆ operator<<

Member Data Documentation

◆ _distributionJointGrid

◆ _distributionSubGrid

◆ _grid