categoricalattributeoperations.java

一个数据挖掘软件ALPHAMINERR的整个过程的JAVA版源代码

/*
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 *    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.
 */

 /**
  * Title: XELOPES Data Mining Library
  * Description: The XELOPES library is an open platform-independent and data-source-independent library for Embedded Data Mining.
  * Copyright: Copyright (c) 2002 Prudential Systems Software GmbH
  * Company: ZSoft (www.zsoft.ru), Prudsys (www.prudsys.com)
  * @author Michael Thess
  * @version 1.2
  */

package com.prudsys.pdm.Core;

import com.prudsys.pdm.Utils.IntVector;

 /**
  * Performs comparisons and basis transformations of categorical attribute. <p>
  *
  * From PDM CWM extension.
  *
  * @see CategoricalAttribute
  */
public class CategoricalAttributeOperations extends com.prudsys.pdm.Cwm.Core.Class
{
    // -----------------------------------------------------------------------
    //  Variables declarations
    // -----------------------------------------------------------------------
    /** Reference to categorical attribute owning this object. */
    protected CategoricalAttribute thisCatAtt;

    /** Pretransformed categorical attribute. Used for caching. */
    private CategoricalAttribute pretransCatAtt = null;

    /** Transformed categorical attribute. Used for caching. */
    private CategoricalAttribute transCatAtt = null;

    /** Indexes of coordinate assignemnt. */
    private IntVector indexAssign = new IntVector();

    // -----------------------------------------------------------------------
    //  Protected constructor
    // -----------------------------------------------------------------------
    /**
     * Protected constructor with categorical attribute object.
     *
     * @param catAtt categorical attribute owning this object
     */
    protected CategoricalAttributeOperations(CategoricalAttribute catAtt)
    {
      this.thisCatAtt = catAtt;
    }

    // -----------------------------------------------------------------------
    //  Getter and setter methods
    // -----------------------------------------------------------------------
    /**
     * Returns reference to categorical attribute object owning this object.
     *
     * @return categorical attribute object owning this object
     */
    public CategoricalAttribute getThisCatAtt()
    {
      return thisCatAtt;
    }

    // -----------------------------------------------------------------------
    //  Basis transformation methods
    // -----------------------------------------------------------------------
    /**
     * Transforms categorical attribute depending on the basis transformation type.
     *
     * Notice that this method can also be applied to a key without passed categorical
     * attribute. In this case the last attribute basis transformation is used
     * as transformation ressource.
     * Such last attribute transformation could have been done either explicitly,
     * applying transform to some categorical attribute, or implicitely, when a key
     * with attribute was transformed. If none of both cases has ever happened,
     * for the key (without attribute) an exception is thrown.
     *
     * @param catAtt categorical attribute of the key
     * @param key key to be transformed with respect to this categorical attribute
     * @return transformed key
     * @exception MiningException cannot transform key
     */
    public double transform(CategoricalAttribute catAtt, double key) throws MiningException  {

      // Transform categories:
      if (catAtt != null) {
        // Use caching if possible:
        if (catAtt != pretransCatAtt) transform(catAtt);
      }
      else {
        if (transCatAtt == null)
          throw new MiningException("No categorical attribute ressource for basis trafo available");
      }

      // Get key:
      int iKey = (int) key;

      // Check key:
      if (iKey >= indexAssign.size()) {
        if (catAtt != null && catAtt.isUnboundedCategories())
          transform(catAtt);
        else
          throw new MiningException("illegal key: " + key + " no category found for attribute: " + catAtt.getName());
      }

      // Transform key:
      int transKey = indexAssign.IntegerAt(iKey);

      return transKey;
    }

    /**
     * Transforms categorical attribute depending on the basis transformation type.
     *
     * @param catAtt categorical attribute to transform
     * @return transformed categorical attribute
     * @exception MiningException cannot transform attribute
     */
    public CategoricalAttribute transform(CategoricalAttribute catAtt) throws MiningException {

      // Transformed categorical attribute;
      CategoricalAttribute ca = new CategoricalAttribute( catAtt.getName() );

      // Init:
      int nThisCatAtt  = thisCatAtt.getCategoriesNumber();
      int nCatAtt      = catAtt.getCategoriesNumber();

      // Go through thisCatAtt and find thisCatAtt->catAtt mapping:
      IntVector invAssign = new IntVector();
      invAssign.setSize(nThisCatAtt);
      for (int i = 0; i < nThisCatAtt; i++) {
        Category cat = thisCatAtt.getCategory(i);
        double key   = catAtt.getKey(cat);
        if ( !Category.isMissingValue(key) ) {
          invAssign.setElementAt( (int) key, i);
          ca.addCategory( catAtt.getCategory(key) );  // add category of catAtt
        }
        else {
          invAssign.setElementAt( -1, i);
          ca.addCategory(cat);     // must add category of thisCatAdd for trafo
        }
      };

      // Calculate inverse mapping:
      indexAssign.setSize(nCatAtt);
      for (int i = 0; i < nCatAtt; i++)
        indexAssign.setElementAt(-1, i);
      for (int i = 0; i < nThisCatAtt; i++) {
        int ind = invAssign.IntegerAt(i);
        if (ind > -1)
          indexAssign.setElementAt(i, ind);
      }

      // Go through catAtt and find catAtt->thisCatAtt mapping:
      int ind = nThisCatAtt;
      for (int i = 0; i < nCatAtt; i++) {
        if (indexAssign.IntegerAt(i) == -1) {
          ca.addCategory( catAtt.getCategory(i) );
          indexAssign.setElementAt(ind, i);
          ind = ind + 1;
        }
      };

      // Copy remaining variables of catAtt:
      ca.setTaxonomy( catAtt.getTaxonomy() );
      ca.setUnboundedCategories( catAtt.isUnboundedCategories() );
      ca.setUnstoredCategories( catAtt.isUnstoredCategories() );

      transCatAtt = ca;

      // For caching:
      pretransCatAtt = catAtt;

      return transCatAtt;