weka.attributeSelection.ASEvaluation Maven / Gradle / Ivy

Show more of this group Show more artifacts with this name
Show all versions of weka-stable Show documentation
The Waikato Environment for Knowledge Analysis (WEKA), a machine learning workbench. This is the stable version. Apart from bugfixes, this version does not receive any other updates.
There is a newer version: 3.8.6
Show newest version
/*
 *   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 3 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, see .
 */

/*
 *    ASEvaluation.java
 *    Copyright (C) 1999-2012 University of Waikato, Hamilton, New Zealand
 *
 */

package weka.attributeSelection;

import weka.core.Capabilities;
import weka.core.CapabilitiesHandler;
import weka.core.CapabilitiesIgnorer;
import weka.core.CommandlineRunnable;
import weka.core.Instances;
import weka.core.RevisionHandler;
import weka.core.RevisionUtils;
import weka.core.SerializedObject;
import weka.core.Utils;

import java.io.Serializable;

/**
 * Abstract attribute selection evaluation class
 * 
 * @author Mark Hall ([email protected])
 * @version $Revision: 12201 $
 */
public abstract class ASEvaluation implements Serializable, CapabilitiesHandler,
  CapabilitiesIgnorer, RevisionHandler, CommandlineRunnable {

  /** for serialization */
  private static final long serialVersionUID = 2091705669885950849L;

  /** Whether capabilities should not be checked */
  protected boolean m_DoNotCheckCapabilities = false;

  /**
   * Returns the tip text for this property
   * 
   * @return tip text for this property suitable for displaying in the
   *         explorer/experimenter gui
   */
  public String doNotCheckCapabilitiesTipText() {
    return "If set, evaluator capabilities are not checked before evaluator is built"
      + " (Use with caution to reduce runtime).";
  }

  /**
   * Set whether not to check capabilities.
   * 
   * @param doNotCheckCapabilities true if capabilities are not to be checked.
   */
  @Override
  public void setDoNotCheckCapabilities(boolean doNotCheckCapabilities) {

    m_DoNotCheckCapabilities = doNotCheckCapabilities;
  }

  /**
   * Get whether capabilities checking is turned off.
   * 
   * @return true if capabilities checking is turned off.
   */
  @Override
  public boolean getDoNotCheckCapabilities() {

    return m_DoNotCheckCapabilities;
  }

  // ===============
  // Public methods.
  // ===============

  /**
   * Generates a attribute evaluator. Has to initialize all fields of the
   * evaluator that are not being set via options.
   * 
   * @param data set of instances serving as training data
   * @exception Exception if the evaluator has not been generated successfully
   */
  public abstract void buildEvaluator(Instances data) throws Exception;

  /**
   * Provides a chance for a attribute evaluator to do any special post
   * processing of the selected attribute set. Can also be used to clean up any
   * data structures post attribute selection.
   * 
   * @param attributeSet the set of attributes found by the search
   * @return a possibly ranked list of postprocessed attributes
   * @exception Exception if postprocessing fails for some reason
   */
  public int[] postProcess(int[] attributeSet) throws Exception {
    return attributeSet;
  }

  /**
   * Creates a new instance of an attribute/subset evaluator given it's class
   * name and (optional) arguments to pass to it's setOptions method. If the
   * evaluator implements OptionHandler and the options parameter is non-null,
   * the evaluator will have it's options set.
   * 
   * @param evaluatorName the fully qualified class name of the evaluator
   * @param options an array of options suitable for passing to setOptions. May
   *          be null.
   * @return the newly created evaluator, ready for use.
   * @exception Exception if the evaluator name is invalid, or the options
   *              supplied are not acceptable to the evaluator
   */
  public static ASEvaluation forName(String evaluatorName, String[] options)
    throws Exception {
    return (ASEvaluation) Utils.forName(ASEvaluation.class, evaluatorName,
      options);
  }

  /**
   * Creates copies of the current evaluator. Note that this method now uses
   * Serialization to perform a deep copy, so the evaluator object must be fully
   * Serializable. Any currently built model will now be copied as well.
   * 
   * @param model an example evaluator to copy
   * @param num the number of evaluator copies to create.
   * @return an array of evaluators.
   * @exception Exception if an error occurs
   */
  public static ASEvaluation[] makeCopies(ASEvaluation model, int num)
    throws Exception {

    if (model == null) {
      throw new Exception("No model evaluator set");
    }
    ASEvaluation[] evaluators = new ASEvaluation[num];
    SerializedObject so = new SerializedObject(model);
    for (int i = 0; i < evaluators.length; i++) {
      evaluators[i] = (ASEvaluation) so.getObject();
    }
    return evaluators;
  }

  /**
   * Returns the capabilities of this evaluator.
   * 
   * @return the capabilities of this evaluator
   * @see Capabilities
   */
  @Override
  public Capabilities getCapabilities() {
    Capabilities result = new Capabilities(this);
    result.enableAll();

    return result;
  }

  /**
   * Returns the revision string.
   * 
   * @return the revision
   */
  @Override
  public String getRevision() {
    return RevisionUtils.extract("$Revision: 12201 $");
  }

  /**
   * Tells the evaluator that the attribute selection process is complete. It
   * can then clean up data structures, references to training data as necessary
   * in order to save memory
   */
  public void clean() {
    // subclasses to override
  }

  /**
   * runs the evaluator with the given commandline options
   * 
   * @param evaluator the evaluator to run
   * @param options the commandline options
   */
  public static void runEvaluator(ASEvaluation evaluator, String[] options) {
    try {
      evaluator.preExecution();
      System.out
        .println(AttributeSelection.SelectAttributes(evaluator, options));
    } catch (Exception e) {
      String msg = e.toString().toLowerCase();
      if ((msg.indexOf("help requested") == -1)
        && (msg.indexOf("no training file given") == -1)) {
        e.printStackTrace();
      }
      System.err.println(e.getMessage());
    }

    try {
      evaluator.postExecution();
    } catch (Exception ex) {
      ex.printStackTrace();
    }
  }

  /**
   * Perform any setup stuff that might need to happen before commandline
   * execution. Subclasses should override if they need to do something here
   *
   * @throws Exception if a problem occurs during setup
   */
  @Override
  public void preExecution() throws Exception {
  }

  /**
   * Execute the supplied object. Subclasses need to override this method.
   *
   * @param toRun the object to execute
   * @param options any options to pass to the object
   * @throws Exception if a problem occurs
   */
  @Override
  public void run(Object toRun, String[] options) throws Exception {
    if (!(toRun instanceof ASEvaluation)) {
      throw new IllegalArgumentException(
        "Object to run is not an instance of ASEValuation!");
    }

    preExecution();
    runEvaluator((ASEvaluation) toRun, options);
    postExecution();
  }

  /**
   * Perform any teardown stuff that might need to happen after execution.
   * Subclasses should override if they need to do something here
   *
   * @throws Exception if a problem occurs during teardown
   */
  @Override
  public void postExecution() throws Exception {
  }
}