weka.classifiers.trees.j48
Class ClassifierTree

java.lang.Object
  |
  +--weka.classifiers.trees.j48.ClassifierTree

All Implemented Interfaces:

Drawable, java.io.Serializable

Direct Known Subclasses:

C45PruneableClassifierTree, PruneableClassifierTree

public class ClassifierTree

extends java.lang.Object

implements Drawable, java.io.Serializable

Class for handling a tree structure used for classification.

Version:

$Revision: 1.17 $

Author:

Eibe Frank (eibe@cs.waikato.ac.nz)

See Also:

Serialized Form

Field Summary

Fields inherited from interface weka.core.Drawable

BayesNet, NOT_DRAWABLE, TREE

Constructor Summary

ClassifierTree(ModelSelection toSelectLocModel)
Constructor.

Method Summary

int	assignIDs(int lastID) Assigns a uniqe id to every node in the tree.
void	buildClassifier(Instances data) Method for building a classifier tree.
void	buildTree(Instances data, boolean keepData) Builds the tree structure.
void	buildTree(Instances train, Instances test, boolean keepData) Builds the tree structure with hold out set
double	classifyInstance(Instance instance) Classifies an instance.
void	cleanup(Instances justHeaderInfo) Cleanup in order to save memory.
double[]	distributionForInstance(Instance instance, boolean useLaplace) Returns class probabilities for a weighted instance.
java.lang.String	graph() Returns graph describing the tree.
int	graphType() Returns the type of graph this classifier represents.
int	numLeaves() Returns number of leaves in tree structure.
int	numNodes() Returns number of nodes in tree structure.
java.lang.String	prefix() Returns tree in prefix order.
java.lang.StringBuffer[]	toSource(java.lang.String className) Returns source code for the tree as an if-then statement.
java.lang.String	toString() Prints tree structure.

Methods inherited from class java.lang.Object

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

Constructor Detail

ClassifierTree

public ClassifierTree(ModelSelection toSelectLocModel)

Constructor.

Method Detail

buildClassifier

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

Method for building a classifier tree.

Throws:

java.lang.Exception - if something goes wrong

buildTree

public void buildTree(Instances data,
                      boolean keepData)
               throws java.lang.Exception

Builds the tree structure.

Parameters:

data - the data for which the tree structure is to be generated.

keepData - is training data to be kept?

Throws:

java.lang.Exception - if something goes wrong

buildTree

public void buildTree(Instances train,
                      Instances test,
                      boolean keepData)
               throws java.lang.Exception

Builds the tree structure with hold out set

Parameters:

train - the data for which the tree structure is to be generated.

test - the test data for potential pruning

keepData - is training Data to be kept?

Throws:

java.lang.Exception - if something goes wrong

classifyInstance

public double classifyInstance(Instance instance)
                        throws java.lang.Exception

Classifies an instance.

Throws:

java.lang.Exception - if something goes wrong

cleanup

public final void cleanup(Instances justHeaderInfo)

Cleanup in order to save memory.

distributionForInstance

public final double[] distributionForInstance(Instance instance,
                                              boolean useLaplace)
                                       throws java.lang.Exception

Returns class probabilities for a weighted instance.

Throws:

java.lang.Exception - if something goes wrong

assignIDs

public int assignIDs(int lastID)

Assigns a uniqe id to every node in the tree.

graphType

public int graphType()

Returns the type of graph this classifier represents.

Specified by:

graphType in interface Drawable

Returns:

Drawable.TREE

graph

public java.lang.String graph()
                       throws java.lang.Exception

Returns graph describing the tree.

Specified by:

graph in interface Drawable

Returns:

the graph described by a string

Throws:

java.lang.Exception - if something goes wrong

prefix

public java.lang.String prefix()
                        throws java.lang.Exception

Returns tree in prefix order.

Throws:

java.lang.Exception - if something goes wrong

toSource

public java.lang.StringBuffer[] toSource(java.lang.String className)
                                  throws java.lang.Exception

Returns source code for the tree as an if-then statement. The class is assigned to variable "p", and assumes the tested instance is named "i". The results are returned as two stringbuffers: a section of code for assignment of the class, and a section of code containing support code (eg: other support methods).

Parameters:

className - the classname that this static classifier has

Returns:

an array containing two stringbuffers, the first string containing assignment code, and the second containing source for support code.

Throws:

java.lang.Exception - if something goes wrong

numLeaves

public int numLeaves()

Returns number of leaves in tree structure.

numNodes

public int numNodes()

Returns number of nodes in tree structure.

toString

public java.lang.String toString()

Prints tree structure.

Overrides:

toString in class java.lang.Object