/*
* 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.
*/
/*
* MIPolyKernel.java
* Copyright (C) 2005 University of Waikato, Hamilton, New Zealand
*
*/
package weka.classifiers.mi.supportVector;
import weka.classifiers.functions.supportVector.PolyKernel;
import weka.core.Capabilities;
import weka.core.Instance;
import weka.core.Instances;
import weka.core.MultiInstanceCapabilitiesHandler;
import weka.core.RevisionUtils;
import weka.core.Capabilities.Capability;
/**
<!-- globalinfo-start -->
* The polynomial kernel : K(x, y) = <x, y>^p or K(x, y) = (<x, y>+1)^p
* <p/>
<!-- globalinfo-end -->
*
<!-- options-start -->
* Valid options are: <p/>
*
* <pre> -D
* Enables debugging output (if available) to be printed.
* (default: off)</pre>
*
* <pre> -no-checks
* Turns off all checks - use with caution!
* (default: checks on)</pre>
*
* <pre> -C <num>
* The size of the cache (a prime number), 0 for full cache and
* -1 to turn it off.
* (default: 250007)</pre>
*
* <pre> -E <num>
* The Exponent to use.
* (default: 1.0)</pre>
*
* <pre> -L
* Use lower-order terms.
* (default: no)</pre>
*
<!-- options-end -->
*
* @author Eibe Frank (eibe@cs.waikato.ac.nz)
* @author Shane Legg (shane@intelligenesis.net) (sparse vector code)
* @author Stuart Inglis (stuart@reeltwo.com) (sparse vector code)
* @author Lin Dong (ld21@cs.waikato.ac.nz) (MIkernel)
* @version $Revision: 1.4 $
*/
public class MIPolyKernel
extends PolyKernel
implements MultiInstanceCapabilitiesHandler {
/** for serialiation */
private static final long serialVersionUID = 7926421479341051777L;
/**
* default constructor - does nothing.
*/
public MIPolyKernel() {
super();
}
/**
* Creates a new <code>MIPolyKernel</code> instance.
*
* @param data the training dataset used.
* @param cacheSize the size of the cache (a prime number)
* @param exponent the exponent to use
* @param lowerOrder whether to use lower-order terms
* @throws Exception if something goes wrong
*/
public MIPolyKernel(Instances data, int cacheSize, double exponent,
boolean lowerOrder) throws Exception {
super(data, cacheSize, exponent, lowerOrder);
}
/**
*
* @param id1 the index of instance 1
* @param id2 the index of instance 2
* @param inst1 the instance 1 object
* @return the dot product
* @throws Exception if something goes wrong
*/
protected double evaluate(int id1, int id2, Instance inst1)
throws Exception {
double result, res;
Instances data1= new Instances(inst1.relationalValue(1));
Instances data2;
if(id1==id2)
data2= new Instances(data1);
else
data2 = new Instances (m_data.instance(id2).relationalValue(1));
res=0;
for(int i=0; i<data1.numInstances();i++){
for (int j=0; j<data2.numInstances(); j++){
result = dotProd(data1.instance(i), data2.instance(j));
// Use lower order terms?
if (getUseLowerOrder()) {
result += 1.0;
}
if (getExponent() != 1.0) {
result = Math.pow(result, getExponent());
}
res += result;
}
}
return res;
}
/**
* Returns the Capabilities of this kernel.
*
* @return the capabilities of this object
* @see Capabilities
*/
public Capabilities getCapabilities() {
Capabilities result = super.getCapabilities();
// attributes
result.enable(Capability.NOMINAL_ATTRIBUTES);
result.enable(Capability.RELATIONAL_ATTRIBUTES);
result.enable(Capability.MISSING_VALUES);
// class
result.enableAllClasses();
// other
result.enable(Capability.ONLY_MULTIINSTANCE);
return result;
}
/**
* Returns the capabilities of this multi-instance kernel for the
* relational data.
*
* @return the capabilities of this object
* @see Capabilities
*/
public Capabilities getMultiInstanceCapabilities() {
Capabilities result = super.getCapabilities();
// class
result.disableAllClasses();
result.enable(Capability.NO_CLASS);
return result;
}
/**
* Returns the revision string.
*
* @return the revision
*/
public String getRevision() {
return RevisionUtils.extract("$Revision: 1.4 $");
}
}