/**
* Copyright (C) 2001-2017 by RapidMiner and the contributors
*
* Complete list of developers available at our web site:
*
* http://rapidminer.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.generator;
import java.util.HashSet;
import java.util.Set;
import com.rapidminer.example.Attribute;
import com.rapidminer.example.Attributes;
import com.rapidminer.example.table.AttributeFactory;
import com.rapidminer.operator.ports.metadata.AttributeMetaData;
import com.rapidminer.operator.ports.metadata.ExampleSetMetaData;
import com.rapidminer.operator.ports.metadata.SetRelation;
import com.rapidminer.tools.Ontology;
import com.rapidminer.tools.RandomGenerator;
import com.rapidminer.tools.math.container.Range;
/**
* Generates a data set for two attributes. The data build three rings which are around each other.
*
* @author Ingo Mierswa
*/
public class RingClusteringFunction extends ClusterFunction {
private double bound = ExampleSetGenerator.DEFAULT_SINGLE_BOUND;
private Attribute label = AttributeFactory.createAttribute("label", Ontology.NOMINAL);
private RandomGenerator random;
public RingClusteringFunction() {
label.getMapping().mapString("core");
label.getMapping().mapString("first_ring");
label.getMapping().mapString("second_ring");
}
/** Does nothing. */
@Override
public void init(RandomGenerator random) {
this.random = random;
}
/** Since circles are used the upper and lower bounds must be the same. */
@Override
public void setLowerArgumentBound(double lower) {
this.bound = lower;
}
@Override
public void setUpperArgumentBound(double upper) {
// not used
this.bound = upper;
}
@Override
public Attribute getLabel() {
return label;
}
@Override
public double calculate(double[] att) throws FunctionException {
if (att.length != 2) {
throw new FunctionException("Ring clustering function", "must have 2 attributes!");
}
if (random.nextDouble() < 0.05) {
int type = random.nextInt(3);
switch (type) {
case 0:
return getLabel().getMapping().mapString("core");
case 1:
return getLabel().getMapping().mapString("first_ring");
case 2:
return getLabel().getMapping().mapString("second_ring");
default:
return getLabel().getMapping().mapString("core");
}
} else {
double radius = Math.sqrt(att[0] * att[0] + att[1] * att[1]);
if (radius < bound / 3.0d) {
return getLabel().getMapping().mapString("core");
} else if (radius < 2 * bound / 3.0d) {
return getLabel().getMapping().mapString("first_ring");
} else {
return getLabel().getMapping().mapString("second_ring");
}
}
}
@Override
public double[] createArguments(int number, RandomGenerator random) throws FunctionException {
if (number != 2) {
throw new FunctionException("Ring clustering function", "must have 2 attributes!");
}
double[] args = new double[number];
int type = random.nextInt(3);
double radius = 0.0d;
switch (type) {
case 0:
radius = random.nextGaussian();
break;
case 1:
radius = bound / 2.0d + random.nextGaussian();
break;
case 2:
radius = bound + random.nextGaussian();
break;
default:
radius = random.nextGaussian();
break;
}
double angle = random.nextDouble() * 2 * Math.PI;
args[0] = radius * Math.cos(angle);
args[1] = radius * Math.sin(angle);
return args;
}
@Override
protected Set<String> getClusterSet() {
HashSet<String> set = new HashSet<String>();
set.add("core");
set.add("first_ring");
set.add("second_ring");
return set;
}
@Override
public int getMinNumberOfAttributes() {
return 2;
}
@Override
public int getMaxNumberOfAttributes() {
return 2;
}
@Override
public ExampleSetMetaData getGeneratedMetaData() {
ExampleSetMetaData emd = new ExampleSetMetaData();
// label
AttributeMetaData amd = new AttributeMetaData("label", Ontology.NOMINAL, Attributes.LABEL_NAME);
amd.setValueSet(getClusterSet(), SetRelation.EQUAL);
emd.addAttribute(amd);
// attributes
for (int i = 0; i < numberOfAttributes; i++) {
amd = new AttributeMetaData("att" + (i + 1), Ontology.REAL);
amd.setValueRange(new Range(Double.NEGATIVE_INFINITY, Double.POSITIVE_INFINITY), SetRelation.SUBSET);
emd.addAttribute(amd);
}
emd.setNumberOfExamples(numberOfExamples);
return emd;
}
}