weka.classifiers.trees.j48

Class GraftSplit

java.lang.Object

weka.classifiers.trees.j48.ClassifierSplitModel

weka.classifiers.trees.j48.GraftSplit

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, java.lang.Comparable, RevisionHandler

public class GraftSplit
extends ClassifierSplitModel
implements java.lang.Comparable

Class implementing a split for nodes added to a tree during grafting.

Version:

$Revision 1.0 $

Author:

Janice Boughton (jrbought@infotech.monash.edu.au)

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
GraftSplit(int a, double v, int t, double c, double l) constructor
GraftSplit(int a, double v, int t, double oC, double[][] counts) constructor

Method Summary

Modifier and Type	Method and Description
int	attribute()
void	buildClassifier(Instances data) builds m_graftdistro using the passed data
double	classProb(int classIndex, Instance instance, int theSubset) returns the probability for instance for the specified class
int	compareTo(java.lang.Object g) method needed for sorting a collection of GraftSplits by laplace value
void	deleteGraftedCases(Instances data) deletes the cases in data that belong to leaf pointed to by the test (i.e.
java.lang.String	dumpLabelG(int index, Instances data) Prints label for subset index of instances (eg class).
NoSplit	getLeaf()
NoSplit	getOtherLeaf()
java.lang.String	getRevision() Returns the revision string.
double	laplaceForSubsetOfInterest()
java.lang.String	leftSide(Instances data) Prints left side of condition satisfied by instances.
int	maxClassForSubsetOfInterest()
double	positives(int subset)
double	positivesForSubsetOfInterest()
java.lang.String	rightSide(int index, Instances data) Prints condition satisfied by instances in subset index.
java.lang.String	sourceExpression(int index, Instances data) Returns a string containing java source code equivalent to the test made at this node.
double	splitPoint()
int	subsetOfInterest()
int	testType() returns the test type
java.lang.String	toString(Instances data) method for returning information about this GraftSplit
double	totalForSubset(int subset)
double	totalForSubsetOfInterest()
double[]	weights(Instance instance) Returns weights if instance is assigned to more than one subset.
int	whichSubset(Instance instance) Returns index of subset instance is assigned to.

Methods inherited from class weka.classifiers.trees.j48.ClassifierSplitModel

checkModel, classifyInstance, classProbLaplace, clone, codingCost, distribution, dumpLabel, dumpModel, numSubsets, resetDistribution, sourceClass, split

Methods inherited from class java.lang.Object

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

Constructor Detail

GraftSplit

public GraftSplit(int a,
                  double v,
                  int t,
                  double c,
                  double l)

constructor

Parameters:

a - the attribute to split on

v - the value of a where split occurs

t - the test type (0 is <=, 1 is >, 2 is =, 3 is !)

c - the class to label the leaf node pointed to by test as.

l - the laplace value (needed when sorting GraftSplits)

GraftSplit

public GraftSplit(int a,
                  double v,
                  int t,
                  double oC,
                  double[][] counts)
           throws java.lang.Exception

constructor

Parameters:

a - the attribute to split on

v - the value of a where split occurs

t - the test type (0 is <=, 1 is >, 2 is =, 3 is !=)

oC - the class to label the leaf node not pointed to by test as.

counts - the distribution for this split

Throws:

java.lang.Exception

Method Detail

deleteGraftedCases

public void deleteGraftedCases(Instances data)

deletes the cases in data that belong to leaf pointed to by the test (i.e. the subset of interest). this is useful so the instances belonging to that leaf aren't passed down the other branch.

Parameters:

data - the instances to delete from

buildClassifier

public void buildClassifier(Instances data)
                     throws java.lang.Exception

builds m_graftdistro using the passed data

Specified by:

buildClassifier in class ClassifierSplitModel

Parameters:

data - the instances to use when creating the distribution

Throws:

java.lang.Exception - if something goes wrong

getLeaf

public NoSplit getLeaf()

Returns:

the NoSplit object for the leaf pointed to by m_testType branch

getOtherLeaf

public NoSplit getOtherLeaf()

Returns:

the NoSplit object for the leaf not pointed to by m_testType branch

dumpLabelG

public final java.lang.String dumpLabelG(int index,
                                         Instances data)
                                  throws java.lang.Exception

Prints label for subset index of instances (eg class).

Parameters:

index - the bag to dump label for

data - to get attribute names and such

Returns:

the label as a string

Throws:

java.lang.Exception - if something goes wrong

subsetOfInterest

public int subsetOfInterest()

Returns:

the subset that is specified by the test type

positivesForSubsetOfInterest

public double positivesForSubsetOfInterest()

Returns:

the number of positive cases in the subset of interest

positives

public double positives(int subset)

Parameters:

subset - the subset to get the positives for

Returns:

the number of positive cases in the specified subset

totalForSubsetOfInterest

public double totalForSubsetOfInterest()

Returns:

the number of instances in the subset of interest

totalForSubset

public double totalForSubset(int subset)

Parameters:

subset - the index of the bag to get the total for

Returns:

the number of instances in the subset

leftSide

public java.lang.String leftSide(Instances data)

Prints left side of condition satisfied by instances.

Specified by:

leftSide in class ClassifierSplitModel

Parameters:

data - the data.

attribute

public int attribute()

Returns:

the index of the attribute to split on

rightSide

public final java.lang.String rightSide(int index,
                                        Instances data)

Prints condition satisfied by instances in subset index.

Specified by:

rightSide in class ClassifierSplitModel

sourceExpression

public final java.lang.String sourceExpression(int index,
                                               Instances data)

Returns a string containing java source code equivalent to the test made at this node. The instance being tested is called "i".

Specified by:

sourceExpression in class ClassifierSplitModel

Parameters:

index - index of the nominal value tested

data - the data containing instance structure info

Returns:

a value of type 'String'

weights

public double[] weights(Instance instance)

Description copied from class: ClassifierSplitModel

Returns weights if instance is assigned to more than one subset. Returns null if instance is only assigned to one subset.

Specified by:

weights in class ClassifierSplitModel

Parameters:

instance - the instance to produce the weights for

Returns:

a double array of weights, null if only belongs to one subset

whichSubset

public int whichSubset(Instance instance)

Description copied from class: ClassifierSplitModel

Returns index of subset instance is assigned to. Returns -1 if instance is assigned to more than one subset.

Specified by:

whichSubset in class ClassifierSplitModel

Parameters:

instance - the instance for which to determine the subset

Returns:

an int indicating the subset this instance belongs to

splitPoint

public double splitPoint()

Returns:

the value of the split point

maxClassForSubsetOfInterest

public int maxClassForSubsetOfInterest()

Returns:

the dominate class for the subset of interest

laplaceForSubsetOfInterest

public double laplaceForSubsetOfInterest()

Returns:

the laplace value for maxClass of subset of interest

testType

public int testType()

returns the test type

Returns:

value of testtype

compareTo

public int compareTo(java.lang.Object g)

method needed for sorting a collection of GraftSplits by laplace value

Specified by:

compareTo in interface java.lang.Comparable

Parameters:

g - the graft split to compare to this one

Returns:

-1, 0, or 1 if this GraftSplit laplace is <, = or > than that of g

classProb

public final double classProb(int classIndex,
                              Instance instance,
                              int theSubset)
                       throws java.lang.Exception

returns the probability for instance for the specified class

Overrides:

classProb in class ClassifierSplitModel

Parameters:

classIndex - the index of the class

instance - the instance to get the probability for

theSubset - the subset

Throws:

java.lang.Exception - if something goes wrong

toString

public java.lang.String toString(Instances data)

method for returning information about this GraftSplit

Parameters:

data - instances for determining names of attributes and values

Returns:

a string showing this GraftSplit's information

getRevision

public java.lang.String getRevision()

Returns the revision string.

Specified by:

getRevision in interface RevisionHandler

Returns:

the revision