package de.lmu.ifi.dbs.elki.datasource.filter;
/*
This file is part of ELKI:
Environment for Developing KDD-Applications Supported by Index-Structures
Copyright (C) 2011
Ludwig-Maximilians-Universität München
Lehr- und Forschungseinheit für Datenbanksysteme
ELKI Development Team
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/>.
*/
import java.util.ArrayList;
import java.util.List;
import de.lmu.ifi.dbs.elki.data.ClassLabel;
import de.lmu.ifi.dbs.elki.data.LabelList;
import de.lmu.ifi.dbs.elki.data.SimpleClassLabel;
import de.lmu.ifi.dbs.elki.data.type.SimpleTypeInformation;
import de.lmu.ifi.dbs.elki.data.type.TypeUtil;
import de.lmu.ifi.dbs.elki.datasource.bundle.MultipleObjectsBundle;
import de.lmu.ifi.dbs.elki.utilities.exceptions.AbortException;
import de.lmu.ifi.dbs.elki.utilities.optionhandling.AbstractParameterizer;
import de.lmu.ifi.dbs.elki.utilities.optionhandling.OptionID;
import de.lmu.ifi.dbs.elki.utilities.optionhandling.constraints.GreaterEqualConstraint;
import de.lmu.ifi.dbs.elki.utilities.optionhandling.parameterization.Parameterization;
import de.lmu.ifi.dbs.elki.utilities.optionhandling.parameters.IntParameter;
import de.lmu.ifi.dbs.elki.utilities.optionhandling.parameters.ObjectParameter;
/**
* Class that turns a label column into a class label column.
*
* @author Erich Schubert
*
* @apiviz.uses LabelList oneway - - «reads»
* @apiviz.has ClassLabel
*/
public class ClassLabelFilter implements ObjectFilter {
/**
* Optional parameter that specifies the index of the label to be used as
* class label, must be an integer equal to or greater than 0.
* <p>
* Key: {@code -dbc.classLabelIndex}
* </p>
*/
public static final OptionID CLASS_LABEL_INDEX_ID = OptionID.getOrCreateOptionID("dbc.classLabelIndex", "The index of the label to be used as class label.");
/**
* Parameter to specify the class of occurring class labels.
* <p>
* Key: {@code -dbc.classLabelClass}
* </p>
*/
public static final OptionID CLASS_LABEL_CLASS_ID = OptionID.getOrCreateOptionID("dbc.classLabelClass", "Class label class to use.");
/**
* The index of the label to be used as class label, null if no class label is
* specified.
*/
private final int classLabelIndex;
/**
* The class label class to use.
*/
private final ClassLabel.Factory<?> classLabelFactory;
/**
* Constructor.
*
* @param classLabelIndex The index to convert
* @param classLabelFactory The class label factory to use
*/
public ClassLabelFilter(int classLabelIndex, ClassLabel.Factory<?> classLabelFactory) {
super();
this.classLabelIndex = classLabelIndex;
this.classLabelFactory = classLabelFactory;
}
@Override
public MultipleObjectsBundle filter(MultipleObjectsBundle objects) {
MultipleObjectsBundle bundle = new MultipleObjectsBundle();
// Find a labellist column
boolean done = false;
boolean keeplabelcol = false;
for(int i = 0; i < objects.metaLength(); i++) {
SimpleTypeInformation<?> meta = objects.meta(i);
// Skip non-labellist columns - or if we already had a labellist
if(done || meta.getRestrictionClass() != LabelList.class) {
bundle.appendColumn(meta, objects.getColumn(i));
continue;
}
done = true;
// We split the label column into two parts
List<ClassLabel> clscol = new ArrayList<ClassLabel>(objects.dataLength());
List<LabelList> lblcol = new ArrayList<LabelList>(objects.dataLength());
// Split the column
for(Object obj : objects.getColumn(i)) {
if(obj != null) {
LabelList ll = (LabelList) obj;
try {
ClassLabel lbl = classLabelFactory.makeFromString(ll.remove(classLabelIndex));
clscol.add(lbl);
}
catch(Exception e) {
throw new AbortException("Cannot initialize class labels: "+e.getMessage(), e);
}
lblcol.add(ll);
if(ll.size() > 0) {
keeplabelcol = true;
}
}
else {
clscol.add(null);
lblcol.add(null);
}
}
bundle.appendColumn(TypeUtil.CLASSLABEL, clscol);
// Only add the label column when it's not empty.
if(keeplabelcol) {
bundle.appendColumn(meta, lblcol);
}
}
return bundle;
}
/**
* Parameterization class.
*
* @author Erich Schubert
*
* @apiviz.exclude
*/
public static class Parameterizer extends AbstractParameterizer {
/**
* The index of the label to be used as class label, null if no class label
* is specified.
*/
protected Integer classLabelIndex;
/**
* The class label factory to use.
*/
private ClassLabel.Factory<?> classLabelFactory;
@Override
protected void makeOptions(Parameterization config) {
super.makeOptions(config);
// parameter class label index
final IntParameter classLabelIndexParam = new IntParameter(CLASS_LABEL_INDEX_ID, new GreaterEqualConstraint(0));
final ObjectParameter<ClassLabel.Factory<?>> classlabelClassParam = new ObjectParameter<ClassLabel.Factory<?>>(CLASS_LABEL_CLASS_ID, ClassLabel.Factory.class, SimpleClassLabel.Factory.class);
config.grab(classLabelIndexParam);
config.grab(classlabelClassParam);
if(classLabelIndexParam.isDefined() && classlabelClassParam.isDefined()) {
classLabelIndex = classLabelIndexParam.getValue();
classLabelFactory = classlabelClassParam.instantiateClass(config);
}
}
@Override
protected Object makeInstance() {
return new ClassLabelFilter(classLabelIndex, classLabelFactory);
}
}
}