exponential.java

一个数据挖掘软件ALPHAMINERR的整个过程的JAVA版源代码

/*
 *    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.
 */

 /**
  * 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 1.0
  */
package com.prudsys.pdm.Transform.OneToOne;

import com.prudsys.pdm.Adapters.PmmlVersion20.DerivedField;
import com.prudsys.pdm.Core.Category;
import com.prudsys.pdm.Core.MiningAttribute;
import com.prudsys.pdm.Core.MiningException;
import com.prudsys.pdm.Core.NumericAttribute;
import com.prudsys.pdm.Transform.OneToOneMapping;

/**
 * Realization of exponential transformation. Inverse of Logarithmic transformation.
 *
 * Missing values are transformed into missing values.
 */
public class Exponential extends OneToOneMapping
{
  // -----------------------------------------------------------------------
  //  Constructor
  // -----------------------------------------------------------------------
  /**
   * Empty constructor.
   */
  public Exponential()
  {
  }

  // -----------------------------------------------------------------------
  //  Transformation methods
  // -----------------------------------------------------------------------
  /**
   * Transforms the source attribute. The result is the target attribute.
   *
   * @return transformed (exponential) attribute
   * @exception MiningException could not transform attribute
   */
  public MiningAttribute transformAttribute() throws MiningException
  {
      if (getSourceAttribute() == null)
        throw new MiningException("Could not find source attribute: " + sourceName);

      if (! (getSourceAttribute() instanceof NumericAttribute))
        throw new MiningException("Source attribute '" + sourceName + "' must be numeric");

      NumericAttribute sourceAttribute      = (NumericAttribute) getSourceAttribute();
      NumericAttribute transformedAttribute = (NumericAttribute) sourceAttribute.clone();

      transformedAttribute.setName( getTargetNameDynamic() );
      transformedAttribute.setLowerBound( Math.exp( sourceAttribute.getLowerBound() ) );
      transformedAttribute.setUpperBound( Math.exp( sourceAttribute.getUpperBound() ) );

      return transformedAttribute;
  }

  /**
   * Transforms attribute value. The result is also a value.
   *
   * @param attributeValue value of attribute to be transformed
   * @return tranformed (exponential) value
   * @exception MiningException could not transform attribute value
   */
  public double transformAttributeValue( double attributeValue ) throws MiningException
  {
      // Missing value:
      if (Category.isMissingValue(attributeValue))
        return attributeValue;

      // Transformation:
      double transformedValue = Math.exp( attributeValue );

      return transformedValue;
  }

  // -----------------------------------------------------------------------
  //  Methods of PMML handling
  // -----------------------------------------------------------------------
  /**
   * Creates PMML object DerivedField of this object of Exponential type.
   *
   * @return DerivedField element
   * @see com.prudsys.pdm.Adapters.PmmlVersion20.Exponential
   * @exception MiningException cannot create PMML object
   */
  public Object createPmmlObject() throws MiningException
  {
      DerivedField field = (DerivedField) super.createPmmlObject();

      com.prudsys.pdm.Adapters.PmmlVersion20.Exponential exponential = new com.prudsys.pdm.Adapters.PmmlVersion20.Exponential();
      exponential.setField( sourceName );

      field.setExponential( exponential );
      return field;
  }

  /**
   * Creates this object from PMML object DerivedField, subobject Exponential.
   *
   * @param pmml DerivedField element
   * @see com.prudsys.pdm.Adapters.PmmlVersion20.Exponential
   * @exception MiningException cannot parse PMML object
   */
  public void parsePmmlObject(Object pmml) throws MiningException
  {
      super.parsePmmlObject(pmml);

      DerivedField field = (DerivedField) pmml;

      com.prudsys.pdm.Adapters.PmmlVersion20.Exponential expo = field.getExponential();
      sourceName = expo.getField();
  }
}