package stream.series.util;



import java.io.Serializable;

import java.util.Vector;



/**

 * This class provides an outline for distance functions on real valued spaces. Coordinates

 * must be provided as {@code Vector}s containing {@code Double} values for each dimension.

 * 

 * @author Markus Kokott ( markus.kokott(at)udo.edu )

 * 27.02.2012

 */

public abstract class Distance implements Serializable {



	

	/**

	 * 

	 */

	private static final long serialVersionUID = -7977518993888146888L;



	public Double getDistance (Vector<Double> coordinates_a, Vector<Double> coordinates_b){

		

		if (coordinates_a.size() != coordinates_b.size() || coordinates_a.isEmpty()){

			

			return Double.NaN;

		}

		

		return this.computeDistance(coordinates_a, coordinates_b);

	}

	

	/**

	 * Override this method for computing a distance. 

	 * @param coordinates_a

	 * @param coordinates_b

	 * @return

	 */

	protected abstract Double computeDistance(Vector<Double> coordinates_a, Vector<Double> coordinates_b);

}