/**
* 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 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
*/
public class GridFunction extends RegressionFunction {
private int[] counter;
private int maxCounter;
private double dimDistance;
@Override
public void init(RandomGenerator random) {
this.counter = new int[numberOfAttributes];
this.maxCounter = (int) Math.round(Math.exp(Math.log(numberOfExamples) / numberOfAttributes));
this.dimDistance = (getUpperArgumentBound() - getLowerArgumentBound()) / this.maxCounter;
}
@Override
public Attribute getLabel() {
return AttributeFactory.createAttribute("label", Ontology.REAL);
}
@Override
public double calculate(double[] att) throws FunctionException {
return 0.0d;
}
@Override
public double[] createArguments(int number, RandomGenerator random) throws FunctionException {
double[] args = new double[number];
for (int i = 0; i < args.length; i++) {
args[i] = getLowerArgumentBound() + (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);
}
}
}
}