attributesetwriter.java

一个很好的LIBSVM的JAVA源码。对于要研究和改进SVM算法的学者。可以参考。来自数据挖掘工具YALE工具包。

/*
 *  YALE - Yet Another Learning Environment
 *  Copyright (C) 2001-2004
 *      Simon Fischer, Ralf Klinkenberg, Ingo Mierswa, 
 *          Katharina Morik, Oliver Ritthoff
 *      Artificial Intelligence Unit
 *      Computer Science Department
 *      University of Dortmund
 *      44221 Dortmund,  Germany
 *  email: [e-mail]
 *  web:   http://yale.cs.uni-dortmund.de/
 *
 *  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., 59 Temple Place, Suite 330, Boston, MA 02111-1307
 *  USA.
 */
package edu.udo.cs.yale.operator.io;

import edu.udo.cs.yale.operator.Operator;
import edu.udo.cs.yale.operator.IOObject;
import edu.udo.cs.yale.operator.OperatorException;
import edu.udo.cs.yale.operator.UserError;
import edu.udo.cs.yale.operator.parameter.*;
import edu.udo.cs.yale.example.AttributeParser;
import edu.udo.cs.yale.example.ExampleSet;
import edu.udo.cs.yale.example.Attribute;
import edu.udo.cs.yale.tools.LogService;

import java.io.*;
import java.util.List;

/** Writes all attributes of an example set to a file. Each line holds the construction
 *  description of one attribute. This file can be read in another experiment using
 *  the {@link edu.udo.cs.yale.operator.preprocessing.FeatureGenerationOperator} or 
 *  {@link AttributeSetLoader}.
 *
 *  @yale.xmlclass AttributeSetWriter
 *  @author Ingo,Simon
 *  @version $Id: AttributeSetWriter.java,v 1.3 2004/08/27 11:57:37 ingomierswa Exp $
 */
public class AttributeSetWriter extends Operator {

    private static final Class[] INPUT_CLASSES  = { ExampleSet.class };
    private static final Class[] OUTPUT_CLASSES = { ExampleSet.class };


    /** Writes the attribute set to a file. */
    public IOObject[] apply() throws OperatorException {
	String generatorFileName = getParameterAsString("attribute_set_file"); 
	File generatorFile = getExperiment().resolveFileName(generatorFileName);
  	ExampleSet eSet = (ExampleSet)getInput(ExampleSet.class, false);
	try {
	    PrintWriter out = new PrintWriter(new FileWriter(generatorFile));
	    for (int i = 0; i < eSet.getNumberOfAttributes(); i++) {
  		Attribute attribute = eSet.getAttribute(i);
  		out.println(attribute.getName() + AttributeParser.NAME_CONSTRUCTION_DESC_SEP + attribute.getConstructionDescription(false));
	    }
	    out.close();
	} catch (IOException e) {
	    throw new UserError(this, e, 303, new Object[] {generatorFile, e.getMessage() });
	}

	return new IOObject[0];
    }

    public Class[] getInputClasses() {
	return INPUT_CLASSES;
    }
    
    public Class[] getOutputClasses() {
	return OUTPUT_CLASSES;
    }

    public List getParameterTypes() {
	List types = super.getParameterTypes();
	types.add(new ParameterTypeFile("attribute_set_file", "Filename for the attribute set file.", false));
	return types;
    }

}