transposeminingstream.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.Special;

import com.prudsys.pdm.Core.MiningDataSpecification;
import com.prudsys.pdm.Core.MiningException;
import com.prudsys.pdm.Core.NumericAttribute;
import com.prudsys.pdm.Input.MiningInputStream;
import com.prudsys.pdm.Input.MiningVector;
import com.prudsys.pdm.Transform.MiningStreamTransformer;

/**
 * Transposes a mining input stream. Especially useful for clustering
 * of attributes.
 *
 * @see MiningInputStream
 */
public class TransposeMiningStream implements MiningStreamTransformer
{
  // -----------------------------------------------------------------------
  //  Constructor
  // -----------------------------------------------------------------------
    /**
     * Empty constructor.
     */
    public TransposeMiningStream() {

    }

    // -----------------------------------------------------------------------
    //  Transformation methods
    // -----------------------------------------------------------------------
  /**
   * Transposes mining input stream. All attributes must be numeric.
   * The targetStream must contain an updatable mining stream.
   *
   * @param sourceStream mining stream used as source of transposition
   * @param targetStream mining stream used as target of transposition
   * @return number of vectors of transformation
   * @exception MiningException can't transpose mining input stream
   */
  public int transform( MiningInputStream sourceStream, MiningInputStream targetStream )
    throws MiningException {

    // New metadata:
    MiningDataSpecification metaDataSource = sourceStream.getMetaData();
    int nAtt = metaDataSource.getAttributesNumber();
    for (int i = 0; i < nAtt; i++)
      if ( !(metaDataSource.getMiningAttribute(i) instanceof NumericAttribute) )
        throw new MiningException("all attributes must be numeric");

    int nAttTrans = sourceStream.getVectorsNumber();
    MiningDataSpecification targetMetaData = new MiningDataSpecification();
    targetMetaData.setRelationName( "Transposed: " + metaDataSource.getRelationName() );
    for (int i = 0; i < nAttTrans; i++)
      targetMetaData.addMiningAttribute( new NumericAttribute("att_" + String.valueOf(i)) );;
    targetStream.updateSetMetaData(targetMetaData);

    // Transpose stream:
    int nVec = nAttTrans;
    targetStream.updateRemoveAllVectors();
    for (int i = 0; i < nAtt; i++) {
      double[] values = new double[nVec];
      for (int j = 0; j < nVec; j++)
        sourceStream.readAttributeValue(j, i);
      MiningVector mv = new MiningVector(values);
      mv.setMetaData(targetMetaData);
      targetStream.updateAppendVector(mv);
    };

    return nVec;
  }
}