/*
* RapidMiner
*
* Copyright (C) 2001-2008 by Rapid-I and the contributors
*
* Complete list of developers available at our web site:
*
* http://rapid-i.com
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see http://www.gnu.org/licenses/.
*/
package com.rapidminer.operator.meta;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import com.rapidminer.example.Attribute;
import com.rapidminer.example.AttributeRole;
import com.rapidminer.example.Attributes;
import com.rapidminer.example.ExampleSet;
import com.rapidminer.operator.IOContainer;
import com.rapidminer.operator.IOObject;
import com.rapidminer.operator.OperatorChain;
import com.rapidminer.operator.OperatorDescription;
import com.rapidminer.operator.OperatorException;
import com.rapidminer.operator.UserError;
import com.rapidminer.operator.condition.InnerOperatorCondition;
import com.rapidminer.operator.condition.SimpleChainInnerOperatorCondition;
/**
* Performs the inner operator for all label attributes, i.e. special attributes
* whose name starts with "label". In each iteration one of the
* multiple labels is used as label. The results of the inner operators are
* collected and returned. The example set will be consumed during the
* iteration.
*
* @author Ingo Mierswa
* @version $Id: MultipleLabelIterator.java,v 1.9 2006/04/05 08:57:26
* ingomierswa Exp $
*/
public class MultipleLabelIterator extends OperatorChain {
public MultipleLabelIterator(OperatorDescription description) {
super(description);
}
public IOObject[] apply() throws OperatorException {
ExampleSet exampleSet = getInput(ExampleSet.class);
Attribute[] labels = getLabels(exampleSet);
if (labels.length == 0)
throw new UserError(this, 105);
List<IOObject> outputs = new LinkedList<IOObject>();
for (int i = 0; i < labels.length; i++) {
ExampleSet cloneSet = (ExampleSet) exampleSet.clone();
cloneSet.getAttributes().setLabel(labels[i]);
IOContainer input = new IOContainer(new IOObject[] { cloneSet });
for (int o = 0; o < getNumberOfOperators(); o++) {
input = getOperator(o).apply(input);
}
// add the result ioobjects to the result list
IOObject[] innerResult = input.getIOObjects();
for (int j = 0; j < innerResult.length; j++)
outputs.add(innerResult[j]);
inApplyLoop();
}
IOObject[] result = new IOObject[outputs.size()];
outputs.toArray(result);
return result;
}
public Class<?>[] getInputClasses() {
return new Class[] { ExampleSet.class };
}
public Class<?>[] getOutputClasses() {
if (getNumberOfOperators() == 0)
return new Class[0];
else
return getOperator(getNumberOfOperators() - 1).getOutputClasses();
}
public int getMinNumberOfInnerOperators() {
return 1;
}
public int getMaxNumberOfInnerOperators() {
return Integer.MAX_VALUE;
}
/**
* Returns true since this operator chain should just return the output of
* the last inner operator.
*/
public boolean shouldReturnInnerOutput() {
return true;
}
/** Returns a simple chain condition. */
public InnerOperatorCondition getInnerOperatorCondition() {
return new SimpleChainInnerOperatorCondition();
}
private Attribute[] getLabels(ExampleSet exampleSet) {
List<Attribute> attributes = new LinkedList<Attribute>();
Iterator<AttributeRole> i = exampleSet.getAttributes().specialAttributes();
while (i.hasNext()) {
AttributeRole role = i.next();
String name = role.getSpecialName();
if (name.startsWith(Attributes.LABEL_NAME))
attributes.add(role.getAttribute());
}
Attribute[] result = new Attribute[attributes.size()];
attributes.toArray(result);
return result;
}
}