org.apache.commons.math3.analysis.interpolation
Class AbstractLinearIntervalsFunction

java.lang.Object
  org.apache.commons.math3.analysis.interpolation.AbstractLinearIntervalsFunction

Direct Known Subclasses:

BiLinearIntervalsFunction, TriLinearIntervalsFunction, UniLinearIntervalsFunction

public abstract class AbstractLinearIntervalsFunction
extends Object

Abstract class for linear interpolation. Allows 1, 2 or 3 dimensions. Owns an optimised indices search.

Since:

2.3

Version:

$Id: AbstractLinearIntervalsFunction.java 17603 2017-05-18 08:28:32Z bignon $

Author:

Sophie LAURENS

Field Summary

protected static double	EPSILON Numerical precision.
protected int	nxmax Maximal indices in the first dimension of fthe tab in dimension 1, 2 and 3.
protected int	nymax Maximal indices in the second dimension of ftab in dimension 2 and 3.
protected int	nzmax Maximal indices in the third dimension of ftab in dimension 3.
protected ISearchIndex	searchXIndex xtab used for search and satisfies condition from SearchIndex.
protected ISearchIndex	searchYIndex ytab used for search and satisfies condition from SearchIndex.
protected ISearchIndex	searchZIndex ztab used for search and satisfies condition from SearchIndex.
protected double[]	xtab Abscissas array.
protected double[]	ytab Ordinates array.
protected double[]	ztab Heights array.

Constructor Summary

AbstractLinearIntervalsFunction()

Method Summary

double[]	getxtab() Gets xtab
protected double	interp1D(double f0, double f1, double x0, double x1, double x) Interpolates in 1D.
protected double	interp2D(double fx0y0, double fx1y0, double fx0y1, double fx1y1, double x0, double x1, double y0, double y1, double x, double y) Interpolates in 2D by 2-successives 1D interpolation.
protected boolean	isNan(double[] val) Tests if an array of double contains NaN values.

Methods inherited from class java.lang.Object

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

Field Detail

EPSILON

protected static final double EPSILON

Numerical precision.

See Also:

Constant Field Values

nxmax

protected int nxmax

Maximal indices in the first dimension of fthe tab in dimension 1, 2 and 3.

nymax

protected int nymax

Maximal indices in the second dimension of ftab in dimension 2 and 3.

nzmax

protected int nzmax

Maximal indices in the third dimension of ftab in dimension 3.

xtab

protected double[] xtab

Abscissas array.

ytab

protected double[] ytab

Ordinates array.

ztab

protected double[] ztab

Heights array.

searchXIndex

protected ISearchIndex searchXIndex

xtab used for search and satisfies condition from SearchIndex.

searchYIndex

protected ISearchIndex searchYIndex

ytab used for search and satisfies condition from SearchIndex.

searchZIndex

protected ISearchIndex searchZIndex

ztab used for search and satisfies condition from SearchIndex.

Constructor Detail

AbstractLinearIntervalsFunction

public AbstractLinearIntervalsFunction()

Method Detail

interp1D

protected double interp1D(double f0,
                          double f1,
                          double x0,
                          double x1,
                          double x)

Interpolates in 1D.

Parameters:

f0 - : f(x0)

f1 - : f(x1)

x0 - : lower bound

x1 - : upper bound

x - : the point where to do the interpolation

Returns:

finterp : f(x) = a x + b.

Preconditions :

x0 different from x1, and x belongs to [x0, x1[

interp2D

protected double interp2D(double fx0y0,
                          double fx1y0,
                          double fx0y1,
                          double fx1y1,
                          double x0,
                          double x1,
                          double y0,
                          double y1,
                          double x,
                          double y)

Interpolates in 2D by 2-successives 1D interpolation. In this case, the first interpolation is in the x direction, and the second in y.

Parameters:

fx0y0 - : f(x0,y0): lower point for the 1st interpolation (the lower bound for the 2nd interpolation).

fx1y0 - : f(x1,y0): upper point for the 1st interpolation (the lower bound for the 2nd interpolation).

fx0y1 - : f(x0,y1): lower point for the 2nd interpolation (the upper bound for the 2nd interpolation).

fx1y1 - : f(x1,y1): upper point for the 2nd interpolation (the upper bound for the 2nd interpolation).

x0 - : lower bound for the first direction

x1 - : upper bound for the first direction

y0 - : lower bound for the second direction

y1 - : upper bound for the second direction

x - : the point where to do the interpolation in the 1st direction

y - : the point where to do the interpolation in the 2nd direction

Returns:

finterp : f(x,y) = b f(x,y0) + (1-b) f(x,y1), and f(x,y0) = a0 f(x0,y0) + (1-a0) f(x1,y0) f(x,y1) = a1 f(x0,y1) + (1-a1) f(x1,y1).

Preconditions :

x0 (resp. y0) different from x1 (resp. y1), and x (resp. y) belongs to [x0, x1[ (resp. [y0, y1[).

isNan

protected boolean isNan(double[] val)

Tests if an array of double contains NaN values.

Parameters:

val - the array

Returns:

true if at least one value is NaN

getxtab

public double[] getxtab()

Gets xtab

Returns:

the x values