/**
* 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.learner.functions.kernel.rvm.kernel;
import java.io.Serializable;
/**
* Abstract base class for all RVM / GP kernels. Please note that all kernel functions must have a
* zero argument constructor.
*
* @author Piotr Kasprzak, Ingo Mierswa
*
*/
public abstract class Kernel implements Serializable {
/**
*
*/
private static final long serialVersionUID = -8434771989480100605L;
/** Constructor(s) */
public Kernel() {}
/** Evaluate kernel */
public abstract double eval(double[] x, double[] y);
/** Calculates l2-norm(x, y)^2 = ||x - y||^2 */
public double norm2(double[] x, double[] y) {
double result = 0, diff;
for (int i = 0; i < x.length; i++) {
diff = x[i] - y[i];
result += diff * diff;
}
return result;
}
}