/*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/*
* NBTreeClassifierTree.java
* Copyright (C) 2004-2012 University of Waikato, Hamilton, New Zealand
*
*/
package weka.classifiers.trees.j48;
import weka.core.Capabilities;
import weka.core.Capabilities.Capability;
import weka.core.Instances;
import weka.core.RevisionUtils;
/**
* Class for handling a naive bayes tree structure used for
* classification.
*
* @author Mark Hall (mhall@cs.waikato.ac.nz)
* @version $Revision: 8034 $
*/
public class NBTreeClassifierTree
extends ClassifierTree {
/** for serialization */
private static final long serialVersionUID = -4472639447877404786L;
public NBTreeClassifierTree(ModelSelection toSelectLocModel) {
super(toSelectLocModel);
}
/**
* Returns default capabilities of the classifier tree.
*
* @return the capabilities of this classifier tree
*/
public Capabilities getCapabilities() {
Capabilities result = super.getCapabilities();
result.disableAll();
// attributes
result.enable(Capability.NOMINAL_ATTRIBUTES);
result.enable(Capability.NUMERIC_ATTRIBUTES);
result.enable(Capability.DATE_ATTRIBUTES);
result.enable(Capability.MISSING_VALUES);
// class
result.enable(Capability.NOMINAL_CLASS);
result.enable(Capability.MISSING_CLASS_VALUES);
// instances
result.setMinimumNumberInstances(0);
return result;
}
/**
* Method for building a naive bayes classifier tree
*
* @exception Exception if something goes wrong
*/
public void buildClassifier(Instances data) throws Exception {
super.buildClassifier(data);
cleanup(new Instances(data, 0));
assignIDs(-1);
}
/**
* Assigns a uniqe id to every node in the tree.
*
public int assignIDs(int lastID) {
int currLastID = lastID + 1;
m_id = currLastID;
if (m_sons != null) {
for (int i = 0; i < m_sons.length; i++) {
currLastID = m_sons[i].assignIDs(currLastID);
}
}
return currLastID;
} */
/**
* Returns a newly created tree.
*
* @param data the training data
* @exception Exception if something goes wrong
*/
protected ClassifierTree getNewTree(Instances data) throws Exception {
ClassifierTree newTree = new NBTreeClassifierTree(m_toSelectModel);
newTree.buildTree(data, false);
return newTree;
}
/**
* Returns a newly created tree.
*
* @param train the training data
* @param test the pruning data.
* @exception Exception if something goes wrong
*/
protected ClassifierTree getNewTree(Instances train, Instances test)
throws Exception {
ClassifierTree newTree = new NBTreeClassifierTree(m_toSelectModel);
newTree.buildTree(train, test, false);
return newTree;
}
/**
* Print the models at the leaves
*
* @return textual description of the leaf models
*/
public String printLeafModels() {
StringBuffer text = new StringBuffer();
if (m_isLeaf) {
text.append("\nLeaf number: " + m_id+" ");
text.append(m_localModel.toString());
text.append("\n");
} else {
for (int i=0;i<m_sons.length;i++) {
text.append(((NBTreeClassifierTree)m_sons[i]).printLeafModels());
}
}
return text.toString();
}
/**
* Prints tree structure.
*/
public String toString() {
try {
StringBuffer text = new StringBuffer();
if (m_isLeaf) {
text.append(": NB");
text.append(m_id);
}else
dumpTreeNB(0,text);
text.append("\n"+printLeafModels());
text.append("\n\nNumber of Leaves : \t"+numLeaves()+"\n");
text.append("\nSize of the tree : \t"+numNodes()+"\n");
return text.toString();
} catch (Exception e) {
e.printStackTrace();
return "Can't print nb tree.";
}
}
/**
* Help method for printing tree structure.
*
* @exception Exception if something goes wrong
*/
private void dumpTreeNB(int depth,StringBuffer text)
throws Exception {
int i,j;
for (i=0;i<m_sons.length;i++) {
text.append("\n");;
for (j=0;j<depth;j++)
text.append("| ");
text.append(m_localModel.leftSide(m_train));
text.append(m_localModel.rightSide(i, m_train));
if (m_sons[i].m_isLeaf) {
text.append(": NB ");
text.append(m_sons[i].m_id);
}else
((NBTreeClassifierTree)m_sons[i]).dumpTreeNB(depth+1,text);
}
}
/**
* Returns graph describing the tree.
*
* @exception Exception if something goes wrong
*/
public String graph() throws Exception {
StringBuffer text = new StringBuffer();
text.append("digraph J48Tree {\n");
if (m_isLeaf) {
text.append("N" + m_id
+ " [label=\"" +
"NB model" + "\" " +
"shape=box style=filled ");
if (m_train != null && m_train.numInstances() > 0) {
text.append("data =\n" + m_train + "\n");
text.append(",\n");
}
text.append("]\n");
}else {
text.append("N" + m_id
+ " [label=\"" +
m_localModel.leftSide(m_train) + "\" ");
if (m_train != null && m_train.numInstances() > 0) {
text.append("data =\n" + m_train + "\n");
text.append(",\n");
}
text.append("]\n");
graphTree(text);
}
return text.toString() +"}\n";
}
/**
* Help method for printing tree structure as a graph.
*
* @exception Exception if something goes wrong
*/
private void graphTree(StringBuffer text) throws Exception {
for (int i = 0; i < m_sons.length; i++) {
text.append("N" + m_id
+ "->" +
"N" + m_sons[i].m_id +
" [label=\"" + m_localModel.rightSide(i,m_train).trim() +
"\"]\n");
if (m_sons[i].m_isLeaf) {
text.append("N" + m_sons[i].m_id +
" [label=\""+"NB Model"+"\" "+
"shape=box style=filled ");
if (m_train != null && m_train.numInstances() > 0) {
text.append("data =\n" + m_sons[i].m_train + "\n");
text.append(",\n");
}
text.append("]\n");
} else {
text.append("N" + m_sons[i].m_id +
" [label=\""+m_sons[i].m_localModel.leftSide(m_train) +
"\" ");
if (m_train != null && m_train.numInstances() > 0) {
text.append("data =\n" + m_sons[i].m_train + "\n");
text.append(",\n");
}
text.append("]\n");
((NBTreeClassifierTree)m_sons[i]).graphTree(text);
}
}
}
/**
* Returns the revision string.
*
* @return the revision
*/
public String getRevision() {
return RevisionUtils.extract("$Revision: 8034 $");
}
}