NAV::CubicSpline< Scalar > Class Template Reference

Cubic Spline class. More...

Classes
class	BandMatrix
	Sparse matrix whose non-zero entries are confined to a diagonal band, comprising the main diagonal and zero or more diagonals on either side. More...
struct	BoundaryCondition
	Boundary conditions for the spline end-points. More...

Public Member Functions
	CubicSpline ()=default
	Default Constructor.
	CubicSpline (const std::vector< Scalar > &X, const std::vector< Scalar > &Y, BoundaryCondition leftBoundaryCondition={ BoundaryCondition::SecondDerivative, 0.0 }, BoundaryCondition rightBoundaryCondition={ BoundaryCondition::SecondDerivative, 0.0 })
	Constructor.
Scalar	derivative (size_t order, Scalar x) const
	Calculates the derivative of the spline.
Scalar	operator() (Scalar x) const
	Interpolates or extrapolates a value on the spline.
void	setBoundaries (BoundaryCondition leftBoundaryCondition, BoundaryCondition rightBoundaryCondition)
	Set the boundaries conditions. Has to be called before setPoints.
void	setPoints (const std::vector< Scalar > &x, const std::vector< Scalar > &y)
	Set the points/knots of the spline and calculate the spline coefficients.
size_t	size () const noexcept
	Returns the size of the spline vector.

Private Member Functions
size_t	findClosestIdx (Scalar x) const
	Finds the closest index so that vals_x[idx] <= x (return 0 if x < vals_x[0])

Private Attributes
BoundaryCondition	boundaryConditionLeft
	Boundary condition for the left knot.
BoundaryCondition	boundaryConditionRight
	Boundary condition for the right knot.
std::vector< Scalar >	coef_b
	Spline coefficients b.
std::vector< Scalar >	coef_c
	Spline coefficients c.
Scalar	coef_c0
	Spline coefficient c0 for left extrapolation.
std::vector< Scalar >	coef_d
	Spline coefficients d.
std::vector< Scalar >	vals_x
	x coordinates of the knots
std::vector< Scalar >	vals_y
	y coordinates of the knots

Detailed Description

template<typename Scalar>
class NAV::CubicSpline< Scalar >

Cubic Spline class.

Constructor & Destructor Documentation

CubicSpline()

template<typename Scalar >

NAV::CubicSpline< Scalar >::CubicSpline ( const std::vector< Scalar > & X, const std::vector< Scalar > & Y, BoundaryCondition leftBoundaryCondition = { BoundaryCondition::SecondDerivative, 0.0 }, BoundaryCondition rightBoundaryCondition = { BoundaryCondition::SecondDerivative, 0.0 } )

inline

Constructor.

Parameters

[in]	X	List of x coordinates for the spline points/knots
[in]	Y	List of y coordinates for the spline points/knots
[in]	leftBoundaryCondition	Boundary condition for the start knot
[in]	rightBoundaryCondition	Boundary condition for the end knot

Member Function Documentation

derivative()

template<typename Scalar >

Scalar NAV::CubicSpline< Scalar >::derivative ( size_t order, Scalar x ) const

inlinenodiscard

Calculates the derivative of the spline.

Parameters

[in]	order	Order of the derivative to calculate (<= 3)
[in]	x	X coordinate to calculate the derivative for

Returns

The derivative of y up to the given order

findClosestIdx()

template<typename Scalar >

size_t NAV::CubicSpline< Scalar >::findClosestIdx ( Scalar x ) const

inlinenodiscardprivate

Finds the closest index so that vals_x[idx] <= x (return 0 if x < vals_x[0])

Parameters

[in]

x

X coordinate to search the closest knot to

Returns

Index of a knot closest to the x coordinate given

operator()()

template<typename Scalar >

Scalar NAV::CubicSpline< Scalar >::operator() ( Scalar x ) const

inlinenodiscard

Interpolates or extrapolates a value on the spline.

Parameters

[in]

x

X coordinate to inter-/extrapolate the value for

Returns

The y coordinate

setBoundaries()

template<typename Scalar >

void NAV::CubicSpline< Scalar >::setBoundaries ( BoundaryCondition leftBoundaryCondition, BoundaryCondition rightBoundaryCondition )

inline

Set the boundaries conditions. Has to be called before setPoints.

Parameters

[in]	leftBoundaryCondition	Boundary condition for the start knot
[in]	rightBoundaryCondition	Boundary condition for the end knot

setPoints()

template<typename Scalar >

void NAV::CubicSpline< Scalar >::setPoints ( const std::vector< Scalar > & x, const std::vector< Scalar > & y )

inline

Set the points/knots of the spline and calculate the spline coefficients.

Parameters

[in]	x	List of x coordinates of the points
[in]	y	List of y coordinates of the points

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

• /home/runner/work/INSTINCT/INSTINCT/src/Navigation/Math/CubicSpline.hpp