math.numerics
Class LegendreInterpolator

java.lang.Object
  math.numerics.LegendreInterpolator

All Implemented Interfaces:

Function

public class LegendreInterpolator
extends java.lang.Object
implements Function

LegendreInterpolator uses a polynomial interpolation formula to evaluate values between data points.

Version:

1.0

Author:

W. Christian

Constructor Summary

LegendreInterpolator(double[] xdata, double[] ydata)
Constructs a Legendre interpolating polynomial from the given data.

Method Summary

double	evaluate(double x) Computes the interpolated y value for a given x value.
double[]	getCoefficients() Gets the polynomial coefficients c in c[0] + c[1] * x + c[2] * x^2 + ....

Methods inherited from class java.lang.Object

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

Constructor Detail

LegendreInterpolator

public LegendreInterpolator(double[] xdata,
                            double[] ydata)

Constructs a Legendre interpolating polynomial from the given data.

Parameters:

xdata - double[]

ydata - double[]

Method Detail

evaluate

public double evaluate(double x)

Computes the interpolated y value for a given x value.

Specified by:

evaluate in interface Function

Parameters:

aNumber - x value.

Returns:

interpolated y value.

getCoefficients

public double[] getCoefficients()

Gets the polynomial coefficients c in c[0] + c[1] * x + c[2] * x^2 + .... This routine should be used with care because the Vandermonde matrix that is being solved is ill conditioned. See Press et al.

Returns:

double[]