distance.java

来自「上传试试看 不知道 是不是一定成功的」· Java 代码 · 共 69 行

/**
 *
 */
package k_means;

/**
 * calculate the distance btween two points
 *
 * @author xiaoge
 *
 */
public class Distance
{
	public static Double calDistance(Double[] a,Double[] b)
	{
		Double Distance;
		Double temp = Double.valueOf(0.0);
		for (int i = 0; i < b.length - 1; i++)
		{
			temp += (a[i]-b[i])*(a[i]-b[i]);
		}
		Distance = Double.valueOf(Math.sqrt(temp.doubleValue()));

		return Distance;

	}
	/**
	 * calculate the distance between two dimension data whose type is integer
	 * @param a is the data  having two dimension  and the type of the data is integer
	 * @param b is the data  having two dimension  and the type of the data is integer
	 * @return
	 */
	public static double calDis(int[] a,double[] b)
	{

		double temp = 0.0;
		temp = (a[0]-b[0])*(a[0]-b[0]) + (a[1]-b[1])*(a[1]-b[1]) ;
		return Math.sqrt(temp);

	}
	/**
	 * calculate the distance between two dimension data whose type is double
	 * @param a is the data  having two dimension  and the type of the data is double
	 * @param b is the data  having two dimension  and the type of the data is double
	 * @return
	 */
	public static double calDisDouble(double[] a, double[] b)
	{
		// TODO Auto-generated method stub
		double temp = 0.0;
		temp = (a[0]-b[0])*(a[0]-b[0]) + (a[1]-b[1])*(a[1]-b[1]) ;
		return Math.sqrt(temp);
	}
	/**
	 *
	 * @param a
	 * @param b
	 * @return
	 */
	public static double calDisPoint(OneData a, OneData b)
	{
		// TODO Auto-generated method stub
		double temp = 0.0;
		temp = (a.x-b.x)*(a.x-b.x) + (a.y-b.y)*(a.y-b.y)  ;
		return Math.sqrt(temp);
	}

}