addnoise.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.
 */

/*
 *    AddNoise.java
 *    Copyright (C) 2000 Gabi Schmidberger.
 */

package weka.filters.unsupervised.attribute;

import weka.filters.*;
import weka.core.Instance;
import weka.core.Instances;
import weka.core.Attribute;
import weka.core.OptionHandler;
import weka.core.Option;
import weka.core.Utils;

import java.util.Random;
import java.util.Enumeration;
import java.util.Vector;

/** 
 * Introduces noise data  a random subsample of the dataset 
 * by changing a given attribute
 * (attribute must be nominal)
 * Valid options are:<p>
 *
 * -C col <br>
 * Index of the attribute to be changed. (default last)<p>
 *
 * -M <br>
 * flag: missing values are treated as an extra value <p>
 *
 * -P num <br>
 * Percentage of noise to be introduced to the data (default 10).<p>
 *
 * -S seed <br>
 * Random number seed for choosing the data to be changed <p>
 * and for choosing the value it is changed to (default 1). <p>
 *
 * @author Gabi Schmidberger ([e-mail])
 * @version $Revision: 1.1.1.1 $ 
 **/
public class AddNoise extends Filter implements UnsupervisedFilter,
						OptionHandler {

  /** The index of the attribute to be changed. */
  private int m_AttIndexSet = -1;

  /** Flag if missing values are taken as value. */
  private boolean m_UseMissing = false;

  /** The subsample size, percent of original set, default 10% */
  private int m_Percent = 10;
  
  /** The random number generator seed */
  private int m_RandomSeed = 1;
  
  /** The attribute's index */
  private int m_AttIndex;

  /** True if the first batch has been done */
  private boolean m_FirstBatchDone = false; 

  /**
   * Returns a string describing this filter
   *
   * @return a description of the filter suitable for
   * displaying in the explorer/experimenter gui
   */
  public String globalInfo() {

    return "An instance filter that changes a percentage of a given"
           + " attributes values. The attribute must be nominal."
           + " Missing value can be treated as value itself.";
  }

 /**
   * 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(
              "\tIndex of the attribute to be changed \n"
              +"\t(default last attribute)",
              "C", 1, "-C <col>"));
    newVector.addElement(new Option(
              "\tTreat missing values as an extra value \n",
              "M", 1, "-M"));
    newVector.addElement(new Option(
              "\tSpecify the percentage of noise introduced \n"
              +"\tto the data (default 10)",
              "P", 1, "-P <num>"));
    newVector.addElement(new Option(
              "\tSpecify the random number seed (default 1)",
              "S", 1, "-S <num>"));

    return newVector.elements();
  }

  /**
   * Parses a list of options for this object. Valid options are:<p>
   *
   * -C col <br>
   * Index of the attribute to be changed. (default last)<p>
   *
   * -M <br>
   * missing values are treated as an extra value <p>
   *
   * -P num <br>
   * Specify the percentage of noise introduced to the data (default 10).<p>
   *
   * -S num <br>
   * Specify the random number seed (default 1).<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 {

    String indexString = Utils.getOption('C', options);
    if (indexString.length() != 0) {
      setAttIndexSet((int)Double.valueOf(indexString).doubleValue());
    } else {
      setAttIndexSet(-1);
    }

    if (Utils.getFlag('M', options)) {
      setUseMissing(true);
    }

    String percentString = Utils.getOption('P', options);
    if (percentString.length() != 0) {
      setPercent((int) Double.valueOf(percentString).doubleValue());
    } else {
      setPercent(10);
    }

    String seedString = Utils.getOption('S', options);
    if (seedString.length() != 0) {
      setRandomSeed(Integer.parseInt(seedString));
    } else {
      setRandomSeed(1);
    }

  }

  /**
   * Gets the current settings of the filter.
   *
   * @return an array of strings suitable for passing to setOptions
   */
  public String [] getOptions() {

    String [] options = new String [8];
    int current = 0;

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

    if (getUseMissing()) {
      options[current++] = "-M";
    }

    options[current++] = "-P"; options[current++] = "" + getPercent();

    options[current++] = "-S"; options[current++] = "" + getRandomSeed();

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

    return "Flag to set if missing values are used.";
  }

  /**
   * Gets the flag if missing values are treated as extra values.
   *
   * @return the flag missing values.
   */
  public boolean getUseMissing() {

    return m_UseMissing;
  }

  /**
   * Sets the flag if missing values are treated as extra values.
   *
   * @param newUseMissing the new flag value.
   */
  public void setUseMissing(boolean newUseMissing) {

    m_UseMissing = newUseMissing;
  }

  /**
   * Returns the tip text for this property
   *
   * @return tip text for this property suitable for
   * displaying in the explorer/experimenter gui
   */
  public String randomSeedTipText() {

    return "Random number seed.";
  }

  /**
   * Gets the random number seed.
   *
   * @return the random number seed.
   */
  public int getRandomSeed() {

    return m_RandomSeed;
  }
  
  /**
   * Sets the random number seed.
   *
   * @param newSeed the new random number seed.
   */
  public void setRandomSeed(int newSeed) {

    m_RandomSeed = newSeed;
  }
  
  /**
   * Returns the tip text for this property
   *
   * @return tip text for this property suitable for
   * displaying in the explorer/experimenter gui
   */
  public String percentTipText() {

    return "Percentage of introduced noise to data.";
  }

  /**
   * Gets the size of noise data as a percentage of the original set.
   *
   * @return the noise data size
   */
  public int getPercent() {

    return m_Percent;
  }
  
  /**
   * Sets the size of noise data, as a percentage of the original set.
   *
   * @param newPercent the subsample set size, between 0 and 100.
   */
  public void setPercent(int newPercent) {

    m_Percent = newPercent;
  }
  
  /**
   * Returns the tip text for this property
   *
   * @return tip text for this property suitable for
   * displaying in the explorer/experimenter gui
   */
  public String attIndexSetTipText() {

    return "Index of the attribute that is to changed.";
  }
  /**
   * Gets the Index of the Attribute that is to be changed.
   *
   * @return the attribute index that is to be changed
   */
  public int getAttIndexSet() {

    return m_AttIndexSet;
  }
  
  /**
   * Sets the Index of the Attribute to be changed.