class Vector2d extends AbstractVector implements Serializable {

    @Override
    public boolean equals(Object o)
    {
        if (!(o instanceof Vector2d))
        {
            return false;
        }

        if (this == o)
        {
            return true;
        }

        Vector2d comp = (Vector2d)o;
        return MathUtil.isZero(myX - comp.myX) && MathUtil.isZero(myY - comp.myY);
    }

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

}