nosplit.java

一个很好的LIBSVM的JAVA源码。对于要研究和改进SVM算法的学者。可以参考。来自数据挖掘工具YALE工具包。

/*
 *  YALE - Yet Another Learning Environment
 *  Copyright (C) 2001-2004
 *      Simon Fischer, Ralf Klinkenberg, Ingo Mierswa, 
 *          Katharina Morik, Oliver Ritthoff
 *      Artificial Intelligence Unit
 *      Computer Science Department
 *      University of Dortmund
 *      44221 Dortmund,  Germany
 *  email: [e-mail]
 *  web:   http://yale.cs.uni-dortmund.de/
 *
 *  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., 59 Temple Place, Suite 330, Boston, MA 02111-1307
 *  USA.
 */
package edu.udo.cs.yale.operator.learner.decisiontree.y45.j48;

import weka.core.*;

/**
 * Class implementing a "no-split"-split.
 *
 * @author Eibe Frank ([e-mail])
 * @version $Revision: 1.3 $
 */
public final class NoSplit extends ClassifierSplitModel{

  /**
   * Creates "no-split"-split for given distribution.
   */
  public NoSplit(Distribution distribution){
    
    m_distribution = new Distribution(distribution);
    m_numSubsets = 1;
  }
  
  /**
   * Creates a "no-split"-split for a given set of instances.
   *
   * @exception Exception if split can't be built successfully
   */
  public final void buildClassifier(Instances instances) 
       throws Exception {

    m_distribution = new Distribution(instances);
    m_numSubsets = 1;
  }

  /**
   * Always returns 0 because only there is only one subset.
   */
  public final int whichSubset(Instance instance){
    
    return 0;
  }

  /**
   * Always returns null because there is only one subset.
   */
  public final double [] weights(Instance instance){

    return null;
  }
  
  /**
   * Does nothing because no condition has to be satisfied.
   */
  public final String leftSide(Instances instances){

    return "";
  }
  
  /**
   * Does nothing because no condition has to be satisfied.
   */
  public final String rightSide(int index, Instances instances){

    return "";
  }

  /**
   * Returns a string containing java source code equivalent to the test
   * made at this node. The instance being tested is called "i".
   *
   * @param index index of the nominal value tested
   * @param data the data containing instance structure info
   * @return a value of type 'String'
   */
  public final String sourceExpression(int index, Instances data) {

    return "true";  // or should this be false??
  }  

}