beginning[beta_a]  = 50
beginning[alpha_a]=  0
beginning[beta_b] = 50
beginning[alpha_b] = 0

parameter[geometry] = closed
parameter[p0c] = 1e6

parameter[custom_attribute1] = "custom::kappa"
parameter[custom_attribute2] = "custom::nu0"
parameter[custom_attribute3] = "custom::eps_k"

! a1: custom, mat6_calc_method = tracking, kappa = 0.23, nu0 = 0.30, eps_k = 0.2
a1: custom, mat6_calc_method = tracking, kappa = 0.61803398875, nu0 = 0.55, eps_k = 0.2
lat: line = (a1)
USE, lat