/*
* 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 2 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, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/*
* MultipleClassifiersCombiner.java
* Copyright (C) 2004 University of Waikato, Hamilton, New Zealand
*
*/
package weka.classifiers;
import weka.core.Capabilities;
import weka.core.Option;
import weka.core.OptionHandler;
import weka.core.Utils;
import weka.core.Capabilities.Capability;
import java.util.Enumeration;
import java.util.Vector;
/**
* Abstract utility class for handling settings common to
* meta classifiers that build an ensemble from multiple classifiers.
*
* @author Eibe Frank (eibe@cs.waikato.ac.nz)
* @version $Revision: 6041 $
*/
public abstract class MultipleClassifiersCombiner extends AbstractClassifier {
/** for serialization */
private static final long serialVersionUID = 2776436621129422119L;
/** Array for storing the generated base classifiers. */
protected Classifier[] m_Classifiers = {
new weka.classifiers.rules.ZeroR()
};
/**
* Returns an enumeration describing the available options
*
* @return an enumeration of all the available options
*/
public Enumeration listOptions() {
Vector newVector = new Vector(1);
newVector.addElement(new Option(
"\tFull class name of classifier to include, followed\n"
+ "\tby scheme options. May be specified multiple times.\n"
+ "\t(default: \"weka.classifiers.rules.ZeroR\")",
"B", 1, "-B <classifier specification>"));
Enumeration enu = super.listOptions();
while (enu.hasMoreElements()) {
newVector.addElement(enu.nextElement());
}
return newVector.elements();
}
/**
* Parses a given list of options. Valid options are:<p>
*
* -B classifierstring <br>
* Classifierstring should contain the full class name of a scheme
* included for selection followed by options to the classifier
* (required, option should be used once for each classifier).<p>
*
* @param options the list of options as an array of strings
* @exception Exception if an option is not supported
*/
public void setOptions(String[] options) throws Exception {
// Iterate through the schemes
Vector classifiers = new Vector();
while (true) {
String classifierString = Utils.getOption('B', options);
if (classifierString.length() == 0) {
break;
}
String [] classifierSpec = Utils.splitOptions(classifierString);
if (classifierSpec.length == 0) {
throw new IllegalArgumentException("Invalid classifier specification string");
}
String classifierName = classifierSpec[0];
classifierSpec[0] = "";
classifiers.addElement(AbstractClassifier.forName(classifierName,
classifierSpec));
}
if (classifiers.size() == 0) {
classifiers.addElement(new weka.classifiers.rules.ZeroR());
}
Classifier [] classifiersArray = new Classifier [classifiers.size()];
for (int i = 0; i < classifiersArray.length; i++) {
classifiersArray[i] = (Classifier) classifiers.elementAt(i);
}
setClassifiers(classifiersArray);
super.setOptions(options);
}
/**
* Gets the current settings of the Classifier.
*
* @return an array of strings suitable for passing to setOptions
*/
public String [] getOptions() {
String [] superOptions = super.getOptions();
int current = 0;
String[] options = new String [superOptions.length + m_Classifiers.length * 2];
for (int i = 0; i < m_Classifiers.length; i++) {
options[current++] = "-B";
options[current++] = "" + getClassifierSpec(i);
}
System.arraycopy(superOptions, 0, options, current,
superOptions.length);
return options;
}
/**
* Returns the tip text for this property
* @return tip text for this property suitable for
* displaying in the explorer/experimenter gui
*/
public String classifiersTipText() {
return "The base classifiers to be used.";
}
/**
* Sets the list of possible classifers to choose from.
*
* @param classifiers an array of classifiers with all options set.
*/
public void setClassifiers(Classifier [] classifiers) {
m_Classifiers = classifiers;
}
/**
* Gets the list of possible classifers to choose from.
*
* @return the array of Classifiers
*/
public Classifier [] getClassifiers() {
return m_Classifiers;
}
/**
* Gets a single classifier from the set of available classifiers.
*
* @param index the index of the classifier wanted
* @return the Classifier
*/
public Classifier getClassifier(int index) {
return m_Classifiers[index];
}
/**
* Gets the classifier specification string, which contains the class name of
* the classifier and any options to the classifier
*
* @param index the index of the classifier string to retrieve, starting from
* 0.
* @return the classifier string, or the empty string if no classifier
* has been assigned (or the index given is out of range).
*/
protected String getClassifierSpec(int index) {
if (m_Classifiers.length < index) {
return "";
}
Classifier c = getClassifier(index);
return c.getClass().getName() + " "
+ Utils.joinOptions(((OptionHandler)c).getOptions());
}
/**
* Returns combined capabilities of the base classifiers, i.e., the
* capabilities all of them have in common.
*
* @return the capabilities of the base classifiers
*/
public Capabilities getCapabilities() {
Capabilities result;
int i;
if (getClassifiers().length == 0) {
result = new Capabilities(this);
result.disableAll();
}
else {
result = (Capabilities) getClassifier(0).getCapabilities().clone();
for (i = 1; i < getClassifiers().length; i++)
result.and(getClassifier(i).getCapabilities());
}
// set dependencies
for (Capability cap: Capability.values())
result.enableDependency(cap);
result.setOwner(this);
return result;
}
}