Class for computing 1D special polynomials and their associated basis functions. More...

#include <fe_base.hpp>

Classes
class	Basis
	Class for evaluating 1D nodal, positive (Bernstein), or integrated (Gerritsma) bases. More...

Public Types
enum	EvalType { ChangeOfBasis = 0, Barycentric = 1, Positive = 2, Integrated = 3, NumEvalTypes = 4 }
	One-dimensional basis evaluation type. More...

Public Member Functions
	Poly_1D ()

const double *	GetPoints (const int p, const int btype)
	Get the coordinates of the points of the given BasisType, btype. More...

const double *	OpenPoints (const int p, const int btype=BasisType::GaussLegendre)
	Get coordinates of an open (GaussLegendre) set of points if degree p. More...

const double *	ClosedPoints (const int p, const int btype=BasisType::GaussLobatto)
	Get coordinates of a closed (GaussLegendre) set of points if degree p. More...

Basis &	GetBasis (const int p, const int btype)
	Get a Poly_1D::Basis object of the given degree and BasisType, btype. More...

	~Poly_1D ()

Static Public Member Functions
static const int *	Binom (const int p)
	Get a pointer to an array containing the binomial coefficients "p choose k" for k=0,...,p for the given p. More...

static void	CalcBasis (const int p, const double x, double *u)
	Evaluate the values of a hierarchical 1D basis at point x hierarchical = k-th basis function is degree k polynomial. More...

static void	CalcBasis (const int p, const double x, Vector &u)
	Evaluate the values of a hierarchical 1D basis at point x hierarchical = k-th basis function is degree k polynomial. More...

static void	CalcBasis (const int p, const double x, double u, double d)
	Evaluate the values and derivatives of a hierarchical 1D basis at point x. More...

static void	CalcBasis (const int p, const double x, Vector &u, Vector &d)
	Evaluate the values and derivatives of a hierarchical 1D basis at point x. More...

static void	CalcBasis (const int p, const double x, double u, double d, double *dd)
	Evaluate the values, derivatives and second derivatives of a hierarchical 1D basis at point x. More...

static void	CalcBasis (const int p, const double x, Vector &u, Vector &d, Vector &dd)
	Evaluate the values, derivatives and second derivatives of a hierarchical 1D basis at point x. More...

static double	CalcDelta (const int p, const double x)
	Evaluate a representation of a Delta function at point x. More...

static void	ChebyshevPoints (const int p, double *x)
	Compute the points for the Chebyshev polynomials of order p and place them in the already allocated x array. More...

static void	CalcBinomTerms (const int p, const double x, const double y, double *u)
	Compute the p terms in the expansion of the binomial (x + y)^p and store them in the already allocated u array. More...

static void	CalcBinomTerms (const int p, const double x, const double y, double u, double d)
	Compute the terms in the expansion of the binomial (x + y)^p and their derivatives with respect to x assuming that dy/dx = -1. Store the results in the already allocated u and d arrays. More...

static void	CalcDBinomTerms (const int p, const double x, const double y, double *d)
	Compute the derivatives (w.r.t. x) of the terms in the expansion of the binomial (x + y)^p assuming that dy/dx = -1. Store the results in the already allocated d array. More...

static void	CalcBernstein (const int p, const double x, double *u)
	Compute the values of the Bernstein basis functions of order p at coordinate x and store the results in the already allocated u array. More...

static void	CalcBernstein (const int p, const double x, Vector &u)
	Compute the values of the Bernstein basis functions of order p at coordinate x and store the results in the already allocated u array. More...

static void	CalcBernstein (const int p, const double x, double u, double d)
	Compute the values and derivatives of the Bernstein basis functions of order p at coordinate x and store the results in the already allocated u and d arrays. More...

static void	CalcBernstein (const int p, const double x, Vector &u, Vector &d)
	Compute the values and derivatives of the Bernstein basis functions of order p at coordinate x and store the results in the already allocated u and d arrays. More...

static void	CalcLegendre (const int p, const double x, double *u)

static void	CalcLegendre (const int p, const double x, double u, double d)

Detailed Description

Class for computing 1D special polynomials and their associated basis functions.

Definition at line 941 of file fe_base.hpp.

Member Enumeration Documentation

◆ EvalType

enum mfem::Poly_1D::EvalType

One-dimensional basis evaluation type.

Enumerator
ChangeOfBasis	Use change of basis, O(p^2) Evals.
Barycentric	Use barycentric Lagrangian interpolation, O(p) Evals.
Positive	Fast evaluation of Bernstein polynomials.
Integrated	Integrated indicator functions (cf. Gerritsma)
NumEvalTypes	Keep count of the number of eval types.

Definition at line 945 of file fe_base.hpp.

Constructor & Destructor Documentation

◆ Poly_1D()

mfem::Poly_1D::Poly_1D ( )

inline

Definition at line 1026 of file fe_base.hpp.

◆ ~Poly_1D()

mfem::Poly_1D::~Poly_1D ( )

Definition at line 2221 of file fe_base.cpp.

Member Function Documentation

◆ Binom()

const int * mfem::Poly_1D::Binom ( const int p )

static

Get a pointer to an array containing the binomial coefficients "p choose k" for k=0,...,p for the given p.

Definition at line 1930 of file fe_base.cpp.

◆ CalcBasis() [1/6]

static void mfem::Poly_1D::CalcBasis	(	const int	p,
		const double	x,
		double *	u
	)

inlinestatic

Evaluate the values of a hierarchical 1D basis at point x hierarchical = k-th basis function is degree k polynomial.

Definition at line 1065 of file fe_base.hpp.

◆ CalcBasis() [2/6]

static void mfem::Poly_1D::CalcBasis	(	const int	p,
		const double	x,
		Vector &	u
	)

inlinestatic

Evaluate the values of a hierarchical 1D basis at point x hierarchical = k-th basis function is degree k polynomial.

Definition at line 1075 of file fe_base.hpp.

◆ CalcBasis() [3/6]

static void mfem::Poly_1D::CalcBasis	(	const int	p,
		const double	x,
		double *	u,
		double *	d
	)

inlinestatic

Evaluate the values and derivatives of a hierarchical 1D basis at point x.

Definition at line 1079 of file fe_base.hpp.

◆ CalcBasis() [4/6]

static void mfem::Poly_1D::CalcBasis	(	const int	p,
		const double	x,
		Vector &	u,
		Vector &	d
	)

inlinestatic

Evaluate the values and derivatives of a hierarchical 1D basis at point x.

Definition at line 1087 of file fe_base.hpp.

◆ CalcBasis() [5/6]

static void mfem::Poly_1D::CalcBasis	(	const int	p,
		const double	x,
		double *	u,
		double *	d,
		double *	dd
	)

inlinestatic

Evaluate the values, derivatives and second derivatives of a hierarchical 1D basis at point x.

Definition at line 1091 of file fe_base.hpp.

◆ CalcBasis() [6/6]

static void mfem::Poly_1D::CalcBasis	(	const int	p,
		const double	x,
		Vector &	u,
		Vector &	d,
		Vector &	dd
	)

inlinestatic

Evaluate the values, derivatives and second derivatives of a hierarchical 1D basis at point x.

Definition at line 1100 of file fe_base.hpp.

◆ CalcBernstein() [1/4]

static void mfem::Poly_1D::CalcBernstein	(	const int	p,
		const double	x,
		double *	u
	)

inlinestatic

Compute the values of the Bernstein basis functions of order p at coordinate x and store the results in the already allocated u array.

Definition at line 1130 of file fe_base.hpp.

◆ CalcBernstein() [2/4]

static void mfem::Poly_1D::CalcBernstein	(	const int	p,
		const double	x,
		Vector &	u
	)

inlinestatic

Compute the values of the Bernstein basis functions of order p at coordinate x and store the results in the already allocated u array.

Definition at line 1136 of file fe_base.hpp.

◆ CalcBernstein() [3/4]

static void mfem::Poly_1D::CalcBernstein	(	const int	p,
		const double	x,
		double *	u,
		double *	d
	)

inlinestatic

Compute the values and derivatives of the Bernstein basis functions of order p at coordinate x and store the results in the already allocated u and d arrays.

Definition at line 1142 of file fe_base.hpp.

◆ CalcBernstein() [4/4]

static void mfem::Poly_1D::CalcBernstein	(	const int	p,
		const double	x,
		Vector &	u,
		Vector &	d
	)

inlinestatic

Compute the values and derivatives of the Bernstein basis functions of order p at coordinate x and store the results in the already allocated u and d arrays.

Definition at line 1148 of file fe_base.hpp.

◆ CalcBinomTerms() [1/2]

void mfem::Poly_1D::CalcBinomTerms	(	const int	p,
		const double	x,
		const double	y,
		double *	u
	)

static

Compute the p terms in the expansion of the binomial (x + y)^p and store them in the already allocated u array.

Definition at line 1979 of file fe_base.cpp.

◆ CalcBinomTerms() [2/2]

void mfem::Poly_1D::CalcBinomTerms	(	const int	p,
		const double	x,
		const double	y,
		double *	u,
		double *	d
	)

static

Compute the terms in the expansion of the binomial (x + y)^p and their derivatives with respect to x assuming that dy/dx = -1. Store the results in the already allocated u and d arrays.

Definition at line 2008 of file fe_base.cpp.

◆ CalcDBinomTerms()

void mfem::Poly_1D::CalcDBinomTerms	(	const int	p,
		const double	x,
		const double	y,
		double *	d
	)

static

Compute the derivatives (w.r.t. x) of the terms in the expansion of the binomial (x + y)^p assuming that dy/dx = -1. Store the results in the already allocated d array.

Definition at line 2043 of file fe_base.cpp.

◆ CalcDelta()

static double mfem::Poly_1D::CalcDelta	(	const int	p,
		const double	x
	)

inlinestatic

Evaluate a representation of a Delta function at point x.

Definition at line 1105 of file fe_base.hpp.

◆ CalcLegendre() [1/2]

void mfem::Poly_1D::CalcLegendre	(	const int	p,
		const double	x,
		double *	u
	)

static

Definition at line 2073 of file fe_base.cpp.

◆ CalcLegendre() [2/2]

void mfem::Poly_1D::CalcLegendre	(	const int	p,
		const double	x,
		double *	u,
		double *	d
	)

static

Definition at line 2087 of file fe_base.cpp.

◆ ChebyshevPoints()

void mfem::Poly_1D::ChebyshevPoints	(	const int	p,
		double *	x
	)

static

Compute the points for the Chebyshev polynomials of order p and place them in the already allocated x array.

Definition at line 1947 of file fe_base.cpp.

◆ ClosedPoints()

const double* mfem::Poly_1D::ClosedPoints	(	const int	p,
		const int	btype = `BasisType::GaussLobatto`
	)

inline

Get coordinates of a closed (GaussLegendre) set of points if degree p.

Definition at line 1049 of file fe_base.hpp.

◆ GetBasis()

Poly_1D::Basis & mfem::Poly_1D::GetBasis	(	const int	p,
		const int	btype
	)

Get a Poly_1D::Basis object of the given degree and BasisType, btype.

Parameters

[in]	p	The polynomial degree of the basis.
[in]	btype	The BasisType.

Returns: A reference to an object of type Poly_1D::Basis that represents the requested basis type.

Definition at line 2196 of file fe_base.cpp.

◆ GetPoints()

const double * mfem::Poly_1D::GetPoints	(	const int	p,
		const int	btype
	)

Get the coordinates of the points of the given BasisType, btype.

Parameters

[in]	p	The polynomial degree; the number of points is `p+1`.
[in]	btype	The BasisType.

Returns: A pointer to an array containing the p+1 coordinates of the points. Returns NULL if the BasisType has no associated set of points.

Definition at line 2172 of file fe_base.cpp.

◆ OpenPoints()

const double* mfem::Poly_1D::OpenPoints	(	const int	p,
		const int	btype = `BasisType::GaussLegendre`
	)

inline

Get coordinates of an open (GaussLegendre) set of points if degree p.

Definition at line 1044 of file fe_base.hpp.

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

fem/fe/fe_base.hpp
fem/fe.cpp
fem/fe/fe_base.cpp

Classes

Public Types

Public Member Functions

Static Public Member Functions

Detailed Description

Member Enumeration Documentation

◆ EvalType

Constructor & Destructor Documentation

◆ Poly_1D()

◆ ~Poly_1D()

Member Function Documentation

◆ Binom()

◆ CalcBasis() [1/6]

◆ CalcBasis() [2/6]

◆ CalcBasis() [3/6]

◆ CalcBasis() [4/6]

◆ CalcBasis() [5/6]

◆ CalcBasis() [6/6]

◆ CalcBernstein() [1/4]

◆ CalcBernstein() [2/4]

◆ CalcBernstein() [3/4]

◆ CalcBernstein() [4/4]

◆ CalcBinomTerms() [1/2]

◆ CalcBinomTerms() [2/2]

◆ CalcDBinomTerms()

◆ CalcDelta()

◆ CalcLegendre() [1/2]

◆ CalcLegendre() [2/2]

◆ ChebyshevPoints()

◆ ClosedPoints()

◆ GetBasis()

◆ GetPoints()

◆ OpenPoints()