/*
* 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.preprocessing.filter;
import java.util.List;
import com.rapidminer.example.Attribute;
import com.rapidminer.example.ExampleSet;
import com.rapidminer.example.set.SortedExampleSet;
import com.rapidminer.operator.IOObject;
import com.rapidminer.operator.Operator;
import com.rapidminer.operator.OperatorDescription;
import com.rapidminer.operator.OperatorException;
import com.rapidminer.operator.UserError;
import com.rapidminer.parameter.ParameterType;
import com.rapidminer.parameter.ParameterTypeCategory;
import com.rapidminer.parameter.ParameterTypeString;
/**
* <p>
* This operator sorts the given example set according to a single attribute. The example
* set is sorted according to the natural order of the values of this attribute either
* in increasing or in decreasing direction.
* </p>
*
* @author Ingo Mierswa
* @version $Id: Sorting.java,v 1.6 2008/07/07 07:06:40 ingomierswa Exp $
*/
public class Sorting extends Operator {
/** The parameter name for "Indicates the attribute which should be used for determining the sorting." */
public static final String PARAMETER_ATTRIBUTE_NAME = "attribute_name";
/** The parameter name for "Indicates the direction of the sorting." */
public static final String PARAMETER_SORTING_DIRECTION = "sorting_direction";
public Sorting(OperatorDescription description) {
super(description);
}
public IOObject[] apply() throws OperatorException {
ExampleSet exampleSet = getInput(ExampleSet.class);
int sortingDirection = getParameterAsInt(PARAMETER_SORTING_DIRECTION);
Attribute sortingAttribute = exampleSet.getAttributes().get(getParameterAsString(PARAMETER_ATTRIBUTE_NAME));
// some checks
if (sortingAttribute == null) {
throw new UserError(this, 111, getParameterAsString(PARAMETER_ATTRIBUTE_NAME));
}
ExampleSet result = new SortedExampleSet(exampleSet, sortingAttribute, sortingDirection);
return new IOObject[] { result };
}
public Class<?>[] getInputClasses() {
return new Class[] { ExampleSet.class };
}
public Class<?>[] getOutputClasses() {
return new Class[] { ExampleSet.class };
}
public List<ParameterType> getParameterTypes() {
List<ParameterType> types = super.getParameterTypes();
types.add(new ParameterTypeString(PARAMETER_ATTRIBUTE_NAME, "Indicates the attribute which should be used for determining the sorting.", false));
types.add(new ParameterTypeCategory(PARAMETER_SORTING_DIRECTION, "Indicates the direction of the sorting.", SortedExampleSet.SORTING_DIRECTIONS, SortedExampleSet.INCREASING));
return types;
}
}