City.java

/*
 * Encog(tm) Java Examples v3.4
 * http://www.heatonresearch.com/encog/
 * https://github.com/encog/encog-java-examples
 *
 * Copyright 2008-2016 Heaton Research, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *   
 * For more information on Heaton Research copyrights, licenses 
 * and trademarks visit:
 * http://www.heatonresearch.com/copyright
 */
package org.encog.examples.ml.tsp;

/**
 * City: Holds the location of a city for the traveling salesman problem.
 * 
 * @author Jeff Heaton
 * @version 2.1
 */
public class City {

	/**
	 * The city's x position.
	 */
	int xpos;

	/**
	 * The city's y position.
	 */
	int ypos;

	/**
	 * Constructor.
	 * 
	 * @param x
	 *            The city's x position
	 * @param y
	 *            The city's y position.
	 */
	public City(final int x, final int y) {
		this.xpos = x;
		this.ypos = y;
	}

	/**
	 * Return's the city's x position.
	 * 
	 * @return The city's x position.
	 */
	int getx() {
		return this.xpos;
	}

	/**
	 * Returns the city's y position.
	 * 
	 * @return The city's y position.
	 */
	int gety() {
		return this.ypos;
	}

	/**
	 * Returns how close the city is to another city.
	 * 
	 * @param cother
	 *            The other city.
	 * @return A distance.
	 */
	public int proximity(final City cother) {
		return proximity(cother.getx(), cother.gety());
	}

	/**
	 * Returns how far this city is from a a specific point. This method uses
	 * the pythagorean theorem to calculate the distance.
	 * 
	 * @param x
	 *            The x coordinate
	 * @param y
	 *            The y coordinate
	 * @return The distance.
	 */
	int proximity(final int x, final int y) {
		final int xdiff = this.xpos - x;
		final int ydiff = this.ypos - y;
		return (int) Math.sqrt(xdiff * xdiff + ydiff * ydiff);
	}
}