Project to steady state

Run the full dynamics, as in project(), but stop once the change has slowed down sufficiently, in the sense that the distance between states at successive time steps is less than tol. You determine how the distance is calculated.

Usage

projectToSteady(
  params,
  effort = params@initial_effort,
  distance_func = distanceSSLogN,
  t_per = 1.5,
  t_max = 100,
  dt = 0.1,
  tol = 0.1 * t_per,
  return_sim = FALSE,
  progress_bar = TRUE,
  info_level = 3,
  method = c("euler", "predictor_corrector"),
  ...
)

Arguments

params: A MizerParams object
effort: The fishing effort to be used throughout the simulation. This is validated by validEffortVector() and can therefore be NULL, a single numeric value used for all gears, an unnamed numeric vector with one entry per gear, or a named numeric vector for some or all gears.
distance_func: A function that will be called after every t_per years with both the previous and the new state and that should return a number that in some sense measures the distance between the states. By default this uses the function distanceSSLogN() that you can use as a model for your own distance function.
t_per: The simulation is broken up into shorter runs of t_per years, after each of which we check for convergence. Default value is 1.5. This should be chosen as an odd multiple of the timestep dt in order to be able to detect period 2 cycles.
t_max: The maximum number of years to run the simulation. Default is 100.
dt: The time step to use in project().
tol: The simulation stops when the relative change in the egg production RDI over t_per years is less than tol for every species.
return_sim: If TRUE, the function returns the MizerSim object holding the result of the simulation run, saved at intervals of t_per. If FALSE (default) the function returns a MizerParams object with the "initial" slots set to the steady state.
progress_bar: A shiny progress object to implement a progress bar in a shiny app. Default FALSE.
info_level: Controls the amount of information messages that are shown. Higher levels lead to more messages.
method: The numerical method to use for the consumer density update. See project().
...: Further arguments will be passed on to your distance function.

Value

If return_sim = FALSE, a MizerParams object with the initial state replaced by the final state found by the steady-state search. If return_sim = TRUE, a MizerSim object containing the intermediate states saved every t_per years.

Usage

Arguments

Value

See also