Lyddane propagation model - mean elements (mean = secular)
mean_kep = CL_ex_meanLyddane(osc_kep [,er,mu,j1jn])
Computes the mean orbital elements from the osculating orbital elements, using Lyddane model.
The mean elements for this model include secular effects only.
The type of orbital elements is the following:

Notes:
- The input argument "zonals" is deprecated as of CelestLab v3.0.0. It has been replaced by "j1jn".
See Propagation models for more details.
Osculating orbital elements (6xN)
(optional) Equatorial radius [m]. Default is %CL_eqRad
(optional) Gravitational constant [m^3/s^2]. Default is %CL_mu
(optional) Vector of zonal harmonics. Default is %CL_j1jn (Nz x 1)
Mean orbital elements (6xN)
CNES - DCT/SB