orb5x::spclibs::Spline1D Struct Reference

1-dimensional B-spline More...

#include "bsplines.hpp"

Collaboration diagram for orb5x::spclibs::Spline1D:

Public Member Functions
int	degree () const
bool	is_initialized () const
Real	knot (int i) const
	Read a knot using the original signed Fortran index convention.
void	set_knot (int i, Real val)
	Replace a knot using the original signed Fortran index convention.
	Spline1D ()=default
	Construct an uninitialized descriptor with empty Kokkos Views.

Public Attributes
Kokkos::View< Real * >	bcoefs
	Spline coefficients.
int	dim = 0
	Dimension of spline space = nints + order - 1.
std::vector< int >	fmap
	Fine to coarse mesh mapping (for non-equidistant)
Kokkos::View< Real ** >	gausw
	Gauss weights (ngauss x nints)
Kokkos::View< Real ** >	gausx
	Gauss abscissas (ngauss x nints)
Real	hinv = 0.0
	Inverse of mesh size (for equidistant grids)
Kokkos::View< Real * >	intspl
	Integral of each spline.
Kokkos::View< Real * >	knots
	Knot sequence (-p:nints+p in Fortran, size 2*p+nints+1)
Real	lperiod = 0.0
	Period length (if periodic)
GBMat	mat
	Interpolation matrix (non-periodic)
PeriodicMat	matp
	Interpolation matrix (periodic)
int	nints = 0
	Number of knot intervals.
bool	nlequid = false
	Is the grid equidistant?
bool	nlppform = true
	Use PPFORM for evaluation?
int	order = 0
	Spline order = degree + 1.
bool	period = false
	Is the grid periodic?
Kokkos::View< Real ** >	ppform
	PPFORM coefficients.
Kokkos::View< Real *** >	val0
	Pre-computed spline values at left boundaries (deriv, basis, interval)
Kokkos::View< Real ** >	valc
	For periodic equidistant: translational invariant values.

Detailed Description

1-dimensional B-spline

Represents a B-spline defined on a 1D grid with:

• Arbitrary order (degree + 1)
• Equidistant or non-equidistant knot sequence
• Optional periodic boundary conditions
• Pre-computed Gauss quadrature points and weights
• Band matrix for interpolation

Constructor & Destructor Documentation

Spline1D()

orb5x::spclibs::Spline1D::Spline1D ( )

default

Construct an uninitialized descriptor with empty Kokkos Views.

Member Function Documentation

degree()

int orb5x::spclibs::Spline1D::degree ( ) const

inline

Returns

Polynomial degree, equal to order-1.

References order.

is_initialized()

bool orb5x::spclibs::Spline1D::is_initialized ( ) const

inline

Returns

true after setup assigns positive order and basis dimension.

References dim, and order.

Referenced by orb5x::spclibs::Spline2D::is_initialized(), and orb5x::spclibs::Spline2D1D::is_initialized().

knot()

Real orb5x::spclibs::Spline1D::knot

(

int

i

)

const

Read a knot using the original signed Fortran index convention.

Parameters

[in]

i

Logical knot index in [-degree(), nints+degree()].

Returns

Knot coordinate in the units of the setup grid.

Note

The View is staged to host and logical index i maps to i + order - 1 in C++ storage.

set_knot()

void orb5x::spclibs::Spline1D::set_knot	(	int	i,
		Real	val
	)

Replace a knot using the original signed Fortran index convention.

Parameters

[in]	i	Logical knot index in [-degree(), nints+degree()].
[in]	val	New coordinate in the units of the setup grid.

Note

This stages the complete knot View through host memory and does not recompute cached basis, quadrature, or matrix data.

Member Data Documentation

bcoefs

Kokkos::View<Real*> orb5x::spclibs::Spline1D::bcoefs

Spline coefficients.

dim

int orb5x::spclibs::Spline1D::dim = 0

Dimension of spline space = nints + order - 1.

Referenced by is_initialized().

fmap

std::vector<int> orb5x::spclibs::Spline1D::fmap

Fine to coarse mesh mapping (for non-equidistant)

gausw

Kokkos::View<Real**> orb5x::spclibs::Spline1D::gausw

Gauss weights (ngauss x nints)

gausx

Kokkos::View<Real**> orb5x::spclibs::Spline1D::gausx

Gauss abscissas (ngauss x nints)

hinv

Real orb5x::spclibs::Spline1D::hinv = 0.0

Inverse of mesh size (for equidistant grids)

intspl

Kokkos::View<Real*> orb5x::spclibs::Spline1D::intspl

Integral of each spline.

knots

Kokkos::View<Real*> orb5x::spclibs::Spline1D::knots

Knot sequence (-p:nints+p in Fortran, size 2*p+nints+1)

lperiod

Real orb5x::spclibs::Spline1D::lperiod = 0.0

Period length (if periodic)

mat

GBMat orb5x::spclibs::Spline1D::mat

Interpolation matrix (non-periodic)

matp

PeriodicMat orb5x::spclibs::Spline1D::matp

Interpolation matrix (periodic)

nints

int orb5x::spclibs::Spline1D::nints = 0

Number of knot intervals.

nlequid

bool orb5x::spclibs::Spline1D::nlequid = false

Is the grid equidistant?

nlppform

bool orb5x::spclibs::Spline1D::nlppform = true

Use PPFORM for evaluation?

order

int orb5x::spclibs::Spline1D::order = 0

Spline order = degree + 1.

Referenced by degree(), and is_initialized().

period

bool orb5x::spclibs::Spline1D::period = false

Is the grid periodic?

ppform

Kokkos::View<Real**> orb5x::spclibs::Spline1D::ppform

PPFORM coefficients.

val0

Kokkos::View<Real***> orb5x::spclibs::Spline1D::val0

Pre-computed spline values at left boundaries (deriv, basis, interval)

valc

Kokkos::View<Real**> orb5x::spclibs::Spline1D::valc

For periodic equidistant: translational invariant values.

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

• bsplines.hpp