/*
* RapidMiner
*
* Copyright (C) 2001-2011 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 com.rapidminer.example.Attribute;
import com.rapidminer.example.Example;
import com.rapidminer.example.ExampleSet;
import com.rapidminer.operator.OperatorDescription;
import com.rapidminer.operator.OperatorException;
import com.rapidminer.operator.ports.metadata.AttributeMetaData;
import com.rapidminer.operator.ports.metadata.ExampleSetMetaData;
import com.rapidminer.operator.preprocessing.AbstractValueProcessing;
import com.rapidminer.tools.Ontology;
import com.rapidminer.tools.math.container.Range;
/**
* This operator simply replaces all values by their absolute
* respective value.
*
* @author Ingo Mierswa, Sebastian Land, Tobias Malbrecht
*/
public class AbsoluteValueFilter extends AbstractValueProcessing {
public AbsoluteValueFilter(OperatorDescription description) {
super(description);
}
@Override
public ExampleSetMetaData applyOnFilteredMetaData(ExampleSetMetaData metaData) {
for (AttributeMetaData amd: metaData.getAllAttributes()) {
if (amd.isNumerical() && !amd.isSpecial()) {
Range range = amd.getValueRange();
amd.setValueRange(new Range(0, Math.max(Math.abs(range.getLower()), Math.abs(range.getUpper()))), amd.getValueSetRelation());
amd.getMean().setUnkown();
}
}
return metaData;
}
@Override
public ExampleSet applyOnFiltered(ExampleSet exampleSet) throws OperatorException {
for (Example example : exampleSet) {
for (Attribute attribute : exampleSet.getAttributes()) {
if (attribute.isNumerical()) {
double value = example.getValue(attribute);
value = Math.abs(value);
example.setValue(attribute, value);
}
}
}
return exampleSet;
}
@Override
protected int[] getFilterValueTypes() {
return new int[] { Ontology.NUMERICAL };
}
@Override
public boolean writesIntoExistingData() {
return true;
}
}