svmattributeeval.java

wekaUT是 university texas austin 开发的基于weka的半指导学习(semi supervised learning)的分类器

/*
 *    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.
 */

/*
 *    SVMAttributeEval.java
 *    Copyright (C) 2002 Eibe Frank
 *    Mod by Kieran Holland
 *
 */

package weka.attributeSelection;

import java.io.*;
import java.util.*;
import weka.core.*;
import weka.classifiers.functions.SMO;
import weka.filters.Filter;
import weka.filters.unsupervised.attribute.MakeIndicator;
import weka.attributeSelection.*;

/** 
 * Class for Evaluating attributes individually by using the SVM
 * classifier. Attributes are ranked by the square of the weight
 * assigned by the SVM. Attribute selection for multiclass problems
 * is handled by ranking attributes for each class seperately
 * using a one-vs-all method and then "dealing" from the top of 
 * each pile to give a final ranking.<p>
 *
 * Valid options are: <p>
 *
 * -X <constant rate of elimination> <br>
 * Specify constant rate at which attributes are eliminated per invocation
 * of the support vector machine. Default = 1.<p>
 * 
 * -Y <percent rate of elimination> <br>
 * Specify the percentage rate at which attributes are eliminated per invocation
 * of the support vector machine. This setting trumps the constant rate setting. 
 * Default = 0 (percentage rate ignored).<p>
 *
 * -Z <threshold for percent elimination> <br>
 * Specify the threshold below which the percentage elimination method
 * reverts to the constant elimination method.<p>
 *
 * -C <complexity parameter> <br>
 * Specify the value of C - the complexity parameter to be passed on
 * to the support vector machine. <p>
 * 
 * -P <episilon> <br>
 * Sets the epsilon for round-off error. (default 1.0e-25)<p>
 *
 * -T <tolerance> <br>
 * Sets the tolerance parameter. (default 1.0e-10)<p>
 *
 * @author Eibe Frank ([e-mail])
 * @author Mark Hall ([e-mail])
 * @version $Revision: 1.1.1.1 $
 */
public class SVMAttributeEval extends AttributeEvaluator
  implements OptionHandler {

  /** The attribute scores */
  private double[] m_attScores;

  /** Constant rate of attribute elimination per iteration */
  private int m_numToEliminate = 1;

  /** Percentage rate of attribute elimination, trumps constant
      rate (above threshold), ignored if = 0  */
  private int m_percentToEliminate = 0;

  /** Threshold below which percent elimination switches to
      constant elimination */
  private int m_percentThreshold = 0;

  /** Complexity parameter to pass on to SMO */
  private double m_smoCParameter = 1.0;

  /** Tolerance parameter to pass on to SMO */
  private double m_smoTParameter = 1.0e-10;

  /** Epsilon parameter to pass on to SMO */
  private double m_smoPParameter = 1.0e-25;

  /** Filter parameter to pass on to SMO */
  private int m_smoFilterType = 0;

  /**
   * Returns a string describing this attribute evaluator
   * @return a description of the evaluator suitable for
   * displaying in the explorer/experimenter gui
   */
  public String globalInfo() {
    return "SVMAttributeEval :\n\nEvaluates the worth of an attribute by "
      + "using an SVM classifier.\n";
  }

  /**
   * Constructor
   */
  public SVMAttributeEval() {
    resetOptions();
  }

  /**
   * Returns an enumeration describing all the available options
   *
   * @return an enumeration of options
   */
  public Enumeration listOptions() {
    Vector newVector = new Vector(4);

    newVector.addElement(
			 new Option(
				    "\tSpecify the constant rate of attribute\n"
				    + "\telimination per invocation of\n"
				    + "\tthe support vector machine.\n"
				    + "\tDefault = 1.",
				    "X",
				    1,
				    "-X <constant rate of elimination>"));

    newVector.addElement(
			 new Option(
				    "\tSpecify the percentage rate of attributes to\n"
				    + "\telimination per invocation of\n"
				    + "\tthe support vector machine.\n"
				    + "\tTrumps constant rate (above threshold).\n"
				    + "\tDefault = 0.",
				    "Y",
				    1,
				    "-Y <percent rate of elimination>"));

    newVector.addElement(
			 new Option(
				    "\tSpecify the threshold below which \n"
				    + "\tpercentage attribute elimination\n"
				    + "\treverts to the constant method.\n",
				    "Z",
				    1,
				    "-Z <threshold for percent elimination>"));


    newVector.addElement(
			 new Option(
				    "\tSpecify the value of P (epsilon\n"
				    + "\tparameter) to pass on to the\n"
				    + "\tsupport vector machine.\n"
				    + "\tDefault = 1.0e-25",
				    "P",
				    1,
				    "-P <epsilon>"));

    newVector.addElement(
			 new Option(
				    "\tSpecify the value of T (tolerance\n"
				    + "\tparameter) to pass on to the\n"
				    + "\tsupport vector machine.\n"
				    + "\tDefault = 1.0e-10",
				    "T",
				    1,
				    "-T <tolerance>"));

    newVector.addElement(
			 new Option(
				    "\tSpecify the value of C (complexity\n"
				    + "\tparameter) to pass on to the\n"
				    + "\tsupport vector machine.\n"
				    + "\tDefault = 1.0",
				    "C",
				    1,
				    "-C <complexity>"));

    newVector.addElement(new Option("\tWhether the SVM should "
				    + "0=normalize/1=standardize/2=neither. "
				    + "(default 0=normalize)",
				    "N",
				    1,
				    "-N"));

    return newVector.elements();
  }

  /**
   * Parses a given list of options
   *
   * Valid options are: <p>
   *
   * -X <constant rate of elimination> <br>
   * Specify constant rate at which attributes are eliminated per invocation
   * of the support vector machine. Default = 1.<p>
   * 
   * -Y <percent rate of elimination> <br>
   * Specify the percentage rate at which attributes are eliminated per invocation
   * of the support vector machine. This setting trumps the constant rate setting. 
   * Default = 0 (percentage rate ignored).<p>
   *
   * -Z <threshold for percent elimination> <br>
   * Specify the threshold below which the percentage elimination method
   * reverts to the constant elimination method.<p>
   *
   * -C <complexity parameter> <br>
   * Specify the value of C - the complexity parameter to be passed on
   * to the support vector machine. <p>
   * 
   * -P <episilon> <br>
   * Sets the epsilon for round-off error. (default 1.0e-25)<p>
   *
   * -T <tolerance> <br>
   * Sets the tolerance parameter. (default 1.0e-10)<p>
   *
   * -N <0|1|2> <br>
   * Whether the SVM should 0=normalize/1=standardize/2=neither. (default 0=normalize)<p>
   *
   * @param options the list of options as an array of strings
   * @exception Exception if an error occurs
   */
  public void setOptions(String[] options) throws Exception {
    String optionString;

    optionString = Utils.getOption('X', options);
    if (optionString.length() != 0) {
      setAttsToEliminatePerIteration(Integer.parseInt(optionString));
    }

    optionString = Utils.getOption('Y', options);
    if (optionString.length() != 0) {
      setPercentToEliminatePerIteration(Integer.parseInt(optionString));
    }

    optionString = Utils.getOption('Z', options);
    if (optionString.length() != 0) {
      setPercentThreshold(Integer.parseInt(optionString));
    }

    optionString = Utils.getOption('P', options);
    if (optionString.length() != 0) {
      setEpsilonParameter((new Double(optionString)).doubleValue());
    }

    optionString = Utils.getOption('T', options);
    if (optionString.length() != 0) {
      setToleranceParameter((new Double(optionString)).doubleValue());
    }

    optionString = Utils.getOption('C', options);
    if (optionString.length() != 0) {
      setComplexityParameter((new Double(optionString)).doubleValue());
    }

    optionString = Utils.getOption('N', options);
    if (optionString.length() != 0) {
      setFilterType(new SelectedTag(Integer.parseInt(optionString), SMO.TAGS_FILTER));
    } else {
      setFilterType(new SelectedTag(SMO.FILTER_NORMALIZE, SMO.TAGS_FILTER));
    }

    Utils.checkForRemainingOptions(options);
  }

  /**
   * Gets the current settings of SVMAttributeEval
   *
   * @return an array of strings suitable for passing to setOptions() 
   */
  public String[] getOptions() {
    String[] options = new String[14];
    int current = 0;

    options[current++] = "-X";
    options[current++] = "" + getAttsToEliminatePerIteration();

    options[current++] = "-Y";
    options[current++] = "" + getPercentToEliminatePerIteration();

    options[current++] = "-Z";
    options[current++] = "" + getPercentThreshold();
		
    options[current++] = "-P";
    options[current++] = "" + getEpsilonParameter();

    options[current++] = "-T";
    options[current++] = "" + getToleranceParameter();		

    options[current++] = "-C";
    options[current++] = "" + getComplexityParameter();		

    options[current++] = "-N";
    options[current++] = "" + m_smoFilterType;		

    while (current < options.length) {
      options[current++] = "";
    }

    return options;
  }

  //________________________________________________________________________

  /**
   * Returns a tip text for this property suitable for display in the
   * GUI
   *
   * @return tip text string describing this property
   */
  public String attsToEliminatePerIterationTipText() {
    return "Constant rate of attribute elimination.";
  }

  /**
   * Returns a tip text for this property suitable for display in the
   * GUI
   *
   * @return tip text string describing this property
   */
  public String percentToEliminatePerIterationTipText() {
    return "Percent rate of attribute elimination.";
  }

  /**
   * Returns a tip text for this property suitable for display in the
   * GUI
   *
   * @return tip text string describing this property
   */
  public String percentThresholdTipText() {
    return "Threshold below which percent elimination reverts to constant elimination.";
  }

  /**
   * Returns a tip text for this property suitable for display in the
   * GUI
   *
   * @return tip text string describing this property
   */
  public String epsilonParameterTipText() {
    return "P epsilon parameter to pass to the SVM";
  }

  /**
   * Returns a tip text for this property suitable for display in the
   * GUI
   *
   * @return tip text string describing this property
   */
  public String toleranceParameterTipText() {
    return "T tolerance parameter to pass to the SVM";