org.apache.commons.math3.analysis.interpolation

Class BicubicSplineFunction

java.lang.Object

org.apache.commons.math3.analysis.interpolation.BicubicSplineFunction

All Implemented Interfaces:

BivariateFunction

 class BicubicSplineFunction
extends java.lang.Object
implements BivariateFunction

2D-spline function.

Field Summary

Fields

Modifier and Type	Field and Description
private double[][]	a Coefficients
private static short	N Number of points.
private BivariateFunction	partialDerivativeX First partial derivative along x.
private BivariateFunction	partialDerivativeXX Second partial derivative along x.
private BivariateFunction	partialDerivativeXY Second crossed partial derivative.
private BivariateFunction	partialDerivativeY First partial derivative along y.
private BivariateFunction	partialDerivativeYY Second partial derivative along y.

Constructor Summary

Constructors

Constructor and Description
BicubicSplineFunction(double[] coeff) Simple constructor.
BicubicSplineFunction(double[] coeff, boolean initializeDerivatives) Simple constructor.

Method Summary

Methods

Modifier and Type	Method and Description
private double	apply(double[] pX, double[] pY, double[][] coeff) Compute the value of the bicubic polynomial.
BivariateFunction	partialDerivativeX()
BivariateFunction	partialDerivativeXX()
BivariateFunction	partialDerivativeXY()
BivariateFunction	partialDerivativeY()
BivariateFunction	partialDerivativeYY()
double	value(double x, double y) Compute the value for the function.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

N

private static final short N

Number of points.

See Also:

Constant Field Values

a

private final double[][] a

Coefficients

partialDerivativeX

private final BivariateFunction partialDerivativeX

First partial derivative along x.

partialDerivativeY

private final BivariateFunction partialDerivativeY

First partial derivative along y.

partialDerivativeXX

private final BivariateFunction partialDerivativeXX

Second partial derivative along x.

partialDerivativeYY

private final BivariateFunction partialDerivativeYY

Second partial derivative along y.

partialDerivativeXY

private final BivariateFunction partialDerivativeXY

Second crossed partial derivative.

Constructor Detail

BicubicSplineFunction

public BicubicSplineFunction(double[] coeff)

Simple constructor.

Parameters:

coeff - Spline coefficients.

BicubicSplineFunction

public BicubicSplineFunction(double[] coeff,
                     boolean initializeDerivatives)

Simple constructor.

Parameters:

coeff - Spline coefficients.

initializeDerivatives - Whether to initialize the internal data needed for calling any of the methods that compute the partial derivatives this function.

Method Detail

value

public double value(double x,
           double y)

Compute the value for the function.

Specified by:

value in interface BivariateFunction

Parameters:

x - Abscissa for which the function value should be computed.

y - Ordinate for which the function value should be computed.

Returns:

the value.

apply

private double apply(double[] pX,
           double[] pY,
           double[][] coeff)

Compute the value of the bicubic polynomial.

Parameters:

pX - Powers of the x-coordinate.

pY - Powers of the y-coordinate.

coeff - Spline coefficients.

Returns:

the interpolated value.

partialDerivativeX

public BivariateFunction partialDerivativeX()

Returns:

the partial derivative wrt x.

partialDerivativeY

public BivariateFunction partialDerivativeY()

Returns:

the partial derivative wrt y.

partialDerivativeXX

public BivariateFunction partialDerivativeXX()

Returns:

the second partial derivative wrt x.

partialDerivativeYY

public BivariateFunction partialDerivativeYY()

Returns:

the second partial derivative wrt y.

partialDerivativeXY

public BivariateFunction partialDerivativeXY()

Returns:

the second partial cross-derivative.