corina.index
Class CubicSpline

java.lang.Object
  |
  +--corina.index.Index
        |
        +--corina.index.CubicSpline

All Implemented Interfaces:

Graphable, Runnable, UndoableEdit

public class CubicSpline

extends Index

A cubic spline index.

The algorithm was (first?) discussed in "The Smoothing Spline: A New Approach to Standardizing Forest Interior Tree-Ring Width Series for Dendroclimatic Studies", Edward R. Cook and Kenneth Peters, Tree-Ring Bulletin, Vol. 41, 1981. The algorithm they used comes from Reinsch, C. H., 1967: "Smoothing by spline functions", Numerische Mathematik 10: 177-83.

The "S" term (smoothing factor?) can be set by the user in the preferences; a lower S-value results in a higher-frequency spline. S=1 is a linear fit, S=0 fits the data exactly, and S=1e-16 seems to be a good starting point for dendro datasets.

The original algorithm was written in ALGOL. I do not claim this is an efficient implementation of it, or that it is correct, or even that I understand it. I copied the ALGOL into Java, and twiddled with it until it seemed to work. If there is a newer algorithm or implementation available, I will be happy to use it.

Version:

$Id: CubicSpline.java,v 1.2 2002/04/29 14:36:30 bitpoet Exp $

Author:

Ken Harris

Fields inherited from class corina.index.Index

data, msg, source

Constructor Summary

CubicSpline(Sample s)
Create a new cubic spline.

Method Summary

int	getID()
String	getName() The name of this index.
void	index() Compute the cubic spline.

Methods inherited from class corina.index.Index

addEdit, apply, canRedo, canUndo, die, getChi2, getData, getPresentationName, getR, getRedoPresentationName, getScale, getStart, getTarget, getUndoPresentationName, isSignificant, redo, replaceEdit, run, setProxy, toString, unapply, undo

Methods inherited from class java.lang.Object

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

Constructor Detail

CubicSpline

public CubicSpline(Sample s)

Create a new cubic spline.

Parameters:

s - the Sample to index

Method Detail

index

public void index()

Compute the cubic spline.

Overrides:

index in class Index

getName

public String getName()

The name of this index.

Overrides:

getName in class Index

Returns:

the name of this index

getID

public int getID()

Overrides:

getID in class Index