class Vector2d extends AbstractVector implements Serializable {

    public double[] toArray(double[] doubles)
    {
        double[] result = doubles == null ? new double[2] : doubles;
        result[0] = myX;
        result[1] = myY;
        return result;
    }

    public  Vector2d(double x, double y);
    public  Vector2d(Vector2d vec);
    public  Vector2d(Vector2i vec);

}