import java.util.Vector;/*********************************************************** A public class the stores the representation of a single * data point in the database. Currently it stores 2D data.*/public class Point{    double x; // store the x-coordinate    double y; // store the y-coordinate        /** Constructor      * Creates a new Point with the given coordinates     * @param xVal Value of x coordinate     * @param yVal Value of y coordinate    */    public Point(double xVal, double yVal)    {        x = xVal;        y = yVal;    }        /** Method to return the Euclidean distance between this point and the given point     * @param p The point to measure the distance to     * @return The euclidean distance     */    public double EuclideanDistance(Point p)    {        return Math.sqrt((p.x - x)*(p.x - x) + (p.y - y)*(p.y -y));    }        /** Returns the value of the x-coordinate of this point     * @return The value of x coordinate     */    public double xVal()    {        return x;    }        /** Returns the value of the y-coordinate of this point     * @return The value of y coordinate     */    public double yVal()    {        return y;    }        /** Method to calculate the mean point of a given vector of points     * @param clust the Vector of points to find the mean of      * @return A point which is the mean of the given vector. Returns (0,0)     * if the Vector is empty     */    static public Point mean(Vector clust)    {        double xsum=0.0;        double ysum=0.0;        int size = clust.size();                if (size == 0)            return new Point (0,0); // no points in Vector, return 0,0        // calcuate the sum of x and y coordinates        for (int j= 0; j < size; j++)                {            Point p = (Point) clust.elementAt(j);            xsum += p.x;            ysum += p.y;        }        return new Point(xsum/size,ysum/size);    }        /** Returns a string representation of the point     * @return x and y coordinates in a string     */    public String toString()    {        return x + " " + y;    }        /** Method to return the value of the n-th requested dimension     * @param index The dimension to return the value of. Must be 0 or 1     * @return The value of the requested dimension    */    public double value(int index) {        if (index == 0)            return x;        else            return y;    }        /** Method to return the number of dimensions in the current point      * @param The number of dimensions. Currently is always 2     */    public static int nAttribs() {        return 2;    }}