Package cnuphys.splot.fit

Class ANonlinearFit

java.lang.Object

cnuphys.splot.fit.ANonlinearFit

All Implemented Interfaces:

IValueGetter

public abstract class ANonlinearFit
extends Object
implements IValueGetter

Constructor Summary

Constructors

Constructor	Description
ANonlinearFit(Fit fit)	Create a Error function Fit

Method Summary

Modifier and Type	Method	Description
double	getChiSquare()	Get the chi square of the fit
double[][]	getCovarianceMatrix()	Get the covariance matrix
double[]	getFitParameters()	Get the fit parameters
protected abstract com.nr.model.MultiFuncd	getFunc()
protected abstract double[]	initialGuess(Fit fit)
double	value(double x)	This method is an "after the fact" evaluator.

Methods inherited from class java.lang.Object

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

Constructor Details

ANonlinearFit

public ANonlinearFit(Fit fit)
              throws IllegalArgumentException

Create a Error function Fit

Parameters:

fit - the fit data

tolerance - the tolerance

Throws:

IllegalArgumentException

Method Details

getFitParameters

public double[] getFitParameters()

Get the fit parameters

Returns:

the fit parameters

getCovarianceMatrix

public double[][] getCovarianceMatrix()

Get the covariance matrix

Returns:

the covariance matrix

getChiSquare

public double getChiSquare()

Get the chi square of the fit

Returns:

the chi square

value

public double value(double x)

This method is an "after the fact" evaluator. After the fit is complete is should be able to use the resulting fit parameters to simply evaluate the function at a given x. The default implementation uses the fitting function _func. This is good in that it guarantees consistency, but the fitting function also computes the derivatives so there is an inefficiency. NOTE: this function is NOT used by the fitting process. It is only for convenience, afterward, such as in plotting.

Specified by:

value in interface IValueGetter

initialGuess

protected abstract double[] initialGuess(Fit fit)

getFunc

protected abstract com.nr.model.MultiFuncd getFunc()