weka.classifiers.trees.j48

Class ClassifierTree

java.lang.Object

weka.classifiers.trees.j48.ClassifierTree

All Implemented Interfaces:

Serializable, CapabilitiesHandler, Drawable, RevisionHandler

Direct Known Subclasses:

C45PruneableClassifierTree, NBTreeClassifierTree, PruneableClassifierTree

public class ClassifierTree
extends Object
implements Drawable, Serializable, CapabilitiesHandler, RevisionHandler

Class for handling a tree structure used for classification.

Version:

$Revision: 8034 $

Author:

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

See Also:

Serialized Form

Field Summary

Fields inherited from interface weka.core.Drawable

BayesNet, Newick, NOT_DRAWABLE, TREE

Constructor Summary

Constructors

Constructor and Description
ClassifierTree(ModelSelection toSelectLocModel) Constructor.

Method Summary

Methods

Modifier and Type	Method and Description
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.
Capabilities	getCapabilities() Returns default capabilities of the classifier tree.
String	getRevision() Returns the revision string.
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.
String	prefix() Returns tree in prefix order.
StringBuffer[]	toSource(String className) Returns source code for the tree as an if-then statement.
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

getCapabilities

public Capabilities getCapabilities()

Returns default capabilities of the classifier tree.

Specified by:

getCapabilities in interface CapabilitiesHandler

Returns:

the capabilities of this classifier tree

See Also:

Capabilities

buildClassifier

public void buildClassifier(Instances data)
                     throws Exception

Method for building a classifier tree.

Parameters:

data - the data to build the tree from

Throws:

Exception - if something goes wrong

buildTree

public void buildTree(Instances data,
             boolean keepData)
               throws 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:

Exception - if something goes wrong

buildTree

public void buildTree(Instances train,
             Instances test,
             boolean keepData)
               throws 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:

Exception - if something goes wrong

classifyInstance

public double classifyInstance(Instance instance)
                        throws Exception

Classifies an instance.

Parameters:

instance - the instance to classify

Returns:

the classification

Throws:

Exception - if something goes wrong

cleanup

public final void cleanup(Instances justHeaderInfo)

Cleanup in order to save memory.

Parameters:

justHeaderInfo -

distributionForInstance

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

Returns class probabilities for a weighted instance.

Parameters:

instance - the instance to get the distribution for

useLaplace - whether to use laplace or not

Returns:

the distribution

Throws:

Exception - if something goes wrong

assignIDs

public int assignIDs(int lastID)

Assigns a uniqe id to every node in the tree.

Parameters:

lastID - the last ID that was assign

Returns:

the new current ID

graphType

public int graphType()

Returns the type of graph this classifier represents.

Specified by:

graphType in interface Drawable

Returns:

Drawable.TREE

graph

public String graph()
             throws Exception

Returns graph describing the tree.

Specified by:

graph in interface Drawable

Returns:

the tree as graph

Throws:

Exception - if something goes wrong

prefix

public String prefix()
              throws Exception

Returns tree in prefix order.

Returns:

the prefix order

Throws:

Exception - if something goes wrong

toSource

public StringBuffer[] toSource(String className)
                        throws 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:

Exception - if something goes wrong

numLeaves

public int numLeaves()

Returns number of leaves in tree structure.

Returns:

the number of leaves

numNodes

public int numNodes()

Returns number of nodes in tree structure.

Returns:

the number of nodes

toString

public String toString()

Prints tree structure.

Overrides:

toString in class Object

Returns:

the tree structure

getRevision

public String getRevision()

Returns the revision string.

Specified by:

getRevision in interface RevisionHandler

Returns:

the revision