package stream.series.util;



import java.util.Vector;



/**

 * simple implementation of euclidean distance for elements in real valued

 * spaces.

 * 

 * @author Markus Kokott ( markus.kokott(at)udo.edu ) 27.02.2012

 */

public class EuclideanDistance extends Distance {



	/**

	 * 

	 */

	private static final long serialVersionUID = -2204313980397092277L;

	private Integer decimals = -1;



	public EuclideanDistance() {



	}



	public EuclideanDistance(Integer decimals) {



		if (decimals > 0) {

			this.decimals = decimals;

		}

	}



	@Override

	protected Double computeDistance(Vector<Double> coordinates_a,

			Vector<Double> coordinates_b) {



		Double sum = 0d;



		for (int i = 0; i < coordinates_a.size(); i++) {



			sum += Math.pow((coordinates_a.get(i) - coordinates_b.get(i)), 2);

		}



		if (this.decimals > 0) {



			return NumericValueTransformator.roundDouble(Math.sqrt(sum),

					this.decimals);

		}

		return Math.sqrt(sum);

	}



}