//-------------------------------------------------------------
        public override Point AddRadiusVectors(Point radiusVector)
        {
            DescartesSystem thisObject = this.ConvertSphericalToDescarte();
            DescartesSystem descarte   = (DescartesSystem)(thisObject.AddRadiusVectors(radiusVector));

            SphericalSystem spherical = descarte.ConvertDescarteToSpherical();

            return(new SphericalSystem(spherical.ro, spherical.thetta, spherical.gamma));
        }
        //-------------------------------------------------------------
        public override Point AddRadiusVectors(Point radiusVector)
        {
            DescartesSystem thisObject = this.ConvertCylindricalToDescarte();
            DescartesSystem descarte   = (DescartesSystem)(thisObject.AddRadiusVectors(radiusVector));

            СylindricalSystem cylindrical = descarte.ConvertDescarteToCylindrical();


            return(new СylindricalSystem(cylindrical.cylindricalRo, cylindrical.cylindricalGamma, cylindrical.cylindricalZ));
        }