weka.classifiers.trees.m5
Class CorrelationSplitInfo

java.lang.Object
  weka.classifiers.trees.m5.CorrelationSplitInfo

All Implemented Interfaces:

java.lang.Cloneable, java.io.Serializable, SplitEvaluate

public final class CorrelationSplitInfo

extends java.lang.Object

implements java.lang.Cloneable, java.io.Serializable, SplitEvaluate

Finds split points using correlation.

Version:

$Revision: 1.1 $

Author:

Mark Hall (mhall@cs.waikato.ac.nz)

See Also:

Serialized Form

Field Summary

private int	m_first the first instance
private int	m_last the last instance
private double	m_maxImpurity the maximum impurity reduction
private int	m_number the number of instances
private int	m_position
private int	m_splitAttr the attribute being tested
private double	m_splitValue the best value on which to split

Constructor Summary

CorrelationSplitInfo(int low, int high, int attr)
Constructs an object which contains the split information

Method Summary

void	attrSplit(int attr, Instances inst) Finds the best splitting point for an attribute in the instances
SplitEvaluate	copy() Makes a copy of this CorrelationSplitInfo object
void	initialize(int low, int high, int attr) Resets the object of split information
double	maxImpurity() Returns the impurity of this split
int	position() Returns the position of the split in the sorted values. -1 indicates that a split could not be found.
int	splitAttr() Returns the attribute used in this split
double	splitValue() Returns the split value

Methods inherited from class java.lang.Object

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

Field Detail

m_first

private int m_first

the first instance

m_last

private int m_last

the last instance

m_position

private int m_position

m_maxImpurity

private double m_maxImpurity

the maximum impurity reduction

m_splitAttr

private int m_splitAttr

the attribute being tested

m_splitValue

private double m_splitValue

the best value on which to split

m_number

private int m_number

the number of instances

Constructor Detail

CorrelationSplitInfo

public CorrelationSplitInfo(int low,
                            int high,
                            int attr)

Constructs an object which contains the split information

Parameters:

low - the index of the first instance

high - the index of the last instance

attr - an attribute

Method Detail

copy

public final SplitEvaluate copy()
                         throws java.lang.Exception

Makes a copy of this CorrelationSplitInfo object

Specified by:

copy in interface SplitEvaluate

Returns:

a copy of the object

Throws:

java.lang.Exception

initialize

public final void initialize(int low,
                             int high,
                             int attr)

Resets the object of split information

Parameters:

low - the index of the first instance

high - the index of the last instance

attr - the attribute

attrSplit

public final void attrSplit(int attr,
                            Instances inst)
                     throws java.lang.Exception

Finds the best splitting point for an attribute in the instances

Specified by:

attrSplit in interface SplitEvaluate

Parameters:

attr - the splitting attribute

inst - the instances

Throws:

java.lang.Exception - if something goes wrong

maxImpurity

public double maxImpurity()

Returns the impurity of this split

Specified by:

maxImpurity in interface SplitEvaluate

Returns:

the impurity of this split

splitAttr

public int splitAttr()

Returns the attribute used in this split

Specified by:

splitAttr in interface SplitEvaluate

Returns:

the attribute used in this split

position

public int position()

Returns the position of the split in the sorted values. -1 indicates that a split could not be found.

Specified by:

position in interface SplitEvaluate

Returns:

an int value

splitValue

public double splitValue()

Returns the split value

Specified by:

splitValue in interface SplitEvaluate

Returns:

the split value