radial_derivative# jeanspy.model.AxisymmetricPlummerModel.radial_derivative Class and construction: AxisymmetricPlummerModel. AxisymmetricPlummerModel.radial_derivative(R, z)[source]# Return d(nu)/dR in pc^-4 at cylindrical coordinates R,z in pc. Coordinates broadcast; R must be nonnegative and both arrays finite and nonempty. Invalid coordinates raise ValueError through density.