Dumux::MonotoneCubicSpline< Scalar > Class Template Reference

A monotone cubic spline. More...

#include <dumux/common/monotonecubicspline.hh>

Inheritance diagram for Dumux::MonotoneCubicSpline< Scalar >:

Description

template<class Scalar = double>
class Dumux::MonotoneCubicSpline< Scalar >

A monotone cubic spline.

Note

Construction after Fritsch & Butland (1984) (see https://doi.org/10.1137/0905021)

The resulting interpolation is globally monotone but only C^1

Public Member Functions
	MonotoneCubicSpline ()=default
	Default constructor. More...
	MonotoneCubicSpline (const std::vector< Scalar > &x, const std::vector< Scalar > &y)
	Construct a monotone cubic spline from the control points (x[i], y[i]) More...
void	updatePoints (const std::vector< Scalar > &x, const std::vector< Scalar > &y)
	Create a monotone cubic spline from the control points (x[i], y[i]) More...
Scalar	eval (const Scalar x) const
	Evaluate the y value at a given x value. More...
Scalar	evalDerivative (const Scalar x) const
	Evaluate the first derivative dy/dx at a given x value. More...
Scalar	evalInverse (const Scalar y) const
	Evaluate the inverse function. More...

Constructor & Destructor Documentation

MonotoneCubicSpline() [1/2]

template<class Scalar = double>

Dumux::MonotoneCubicSpline< Scalar >::MonotoneCubicSpline ( )

default

Default constructor.

MonotoneCubicSpline() [2/2]

template<class Scalar = double>

Dumux::MonotoneCubicSpline< Scalar >::MonotoneCubicSpline ( const std::vector< Scalar > &  x, const std::vector< Scalar > &  y  )

inline

Construct a monotone cubic spline from the control points (x[i], y[i])

Note

if the data set is monotone, monotonicity is preserved

Parameters

x	a vector of x-coordinates
y	a vector of y-coordinates

Member Function Documentation

eval()

template<class Scalar = double>

Scalar Dumux::MonotoneCubicSpline< Scalar >::eval ( const Scalar  x ) const

inline

Evaluate the y value at a given x value.

Parameters

x	the x-coordinate

Note

We extrapolate linearly if out of bounds

evalDerivative()

template<class Scalar = double>

Scalar Dumux::MonotoneCubicSpline< Scalar >::evalDerivative ( const Scalar  x ) const

inline

Evaluate the first derivative dy/dx at a given x value.

Parameters

x	the x-coordinate

Note

We extrapolate linearly if out of bounds

evalInverse()

template<class Scalar = double>

Scalar Dumux::MonotoneCubicSpline< Scalar >::evalInverse ( const Scalar  y ) const

inline

Evaluate the inverse function.

Parameters

y	the y-coordinate

Note

We extrapolate linearly if out of bounds

Throws exception if inverse could not be found (e.g. not unique)

updatePoints()

template<class Scalar = double>

void Dumux::MonotoneCubicSpline< Scalar >::updatePoints ( const std::vector< Scalar > &  x, const std::vector< Scalar > &  y  )

inline

Create a monotone cubic spline from the control points (x[i], y[i])

Parameters

x	a vector of x-coordinates
y	a vector of y-coordinates

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

• monotonecubicspline.hh