/*
* 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.generator;
import com.rapidminer.example.Attribute;
import com.rapidminer.example.table.AttributeFactory;
import com.rapidminer.tools.Ontology;
import com.rapidminer.tools.RandomGenerator;
/** Generates a uniformly distributed grid in the given dimensions.
*
* @author Ingo Mierswa
* @version $Id: GridFunction.java,v 1.3 2008/05/09 19:22:51 ingomierswa Exp $
*/
public class GridFunction implements TargetFunction {
private double lowerBound = -10.0d;
private double upperBound = 10.0d;
private int numberOfExamples;
private int numberOfAttributes;
private int[] counter;
private int maxCounter;
private double dimDistance;
public void init(RandomGenerator random) {
this.counter = new int[numberOfAttributes];
this.maxCounter = (int) Math.round(Math.exp(Math.log(numberOfExamples) / numberOfAttributes));
this.dimDistance = (upperBound - lowerBound) / this.maxCounter;
}
public void setTotalNumberOfExamples(int number) {
this.numberOfExamples = number;
}
public void setTotalNumberOfAttributes(int number) {
this.numberOfAttributes = number;
}
public void setLowerArgumentBound(double lower) {
this.lowerBound = lower;
}
public void setUpperArgumentBound(double upper) {
this.upperBound = upper;
}
public Attribute getLabel() {
return AttributeFactory.createAttribute("label", Ontology.REAL);
}
public double calculate(double[] att) throws FunctionException {
return 0.0d;
}
public double[] createArguments(int number, RandomGenerator random) throws FunctionException {
if (number <= 0)
throw new FunctionException("Grid function", "must have at least one attribute!");
double[] args = new double[number];
for (int i = 0; i < args.length; i++) {
args[i] = lowerBound + (dimDistance / 2.0d) + counter[i] * dimDistance;
}
incrementCounter(counter, 0);
return args;
}
private void incrementCounter(int[] counter, int pos) {
counter[pos]++;
if (counter[pos] >= maxCounter) {
counter[pos] = 0;
if (pos < counter.length - 1) {
incrementCounter(counter, pos + 1);
}
}
}
}