Initialise age structure for a simulation replicate

Simulates or reads in initial age deviations and calls Get_Init_NAA to compute both the fished and unfished equilibrium numbers-at-age for year 1 and season 1. Results are written directly into the simulation environment arrays NAA and NAA0. This function is called once per simulation replicate at y = 1 by run_annual_cycle.

Usage

generate_initial_age_structure(y, sim, sim_env)

Arguments

y

Integer. Year index (must be 1).

sim

Integer. Simulation replicate index.

sim_env

Simulation environment created by Setup_sim_env. Modified in place: $ln_InitDevs, $NAA[,,1,1,,,sim], and $NAA0[,,1,1,,,sim] are updated.

Value

invisible(NULL). All modifications are made by reference within sim_env.

Details

Initial deviation sharing follows the same logic as the estimation model: deviations are drawn once per population when n_pop > 1, or once per region when n_pop = 1 and init_dd = 0 (local density-dependence). If ln_InitDevs_input exists in the simulation environment, those values are used directly rather than simulating new draws. Populations with R0 = 0 receive zero deviations. The equilibrium solver uses init_iter = n_ages × 5 iterations.