R/simulate_pc.R

In Giappo/mbd.AsymmetricConditioning: Study the asymmetric conditioning for mbd

#' @export
simulate_pc <- function(
  pars,
  age,
  n_sims = 1e4,
  saveit = TRUE
) {

  full_filename <- get_full_filename(
    pars = pars,
    age = age
  )
  delete_file <- FALSE
  if (file.exists(full_filename)) {
    load(full_filename)
    if (measure$n_sims >= n_sims) {
      return(measure$pc_sim)
    } else {
      delete_file <- TRUE
    }
  }

  n_0 <- 2
  score <- 0
  for (seed in 1:n_sims) {
    sim <- mbd::mbd_sim(
      pars = pars,
      n_0 = n_0,
      cond = 0,
      age = age,
      seed = seed
    )

    l_matrix <- sim$l_matrix
    alive <- l_matrix[l_matrix[, 4] == -1, ]
    alive <- matrix(alive, ncol = 4)
    crown_species_dead <- (length(unique(sign(alive[, 3]))) != n_0)
    crown_survival <- !crown_species_dead

    score <- score + 1 * crown_survival
  }
  pc_sim <- score / n_sims
  if (saveit == TRUE) {
    measure <- list(
      pc_sim = pc_sim,
      n_sims = n_sims
    )
    if (delete_file == TRUE) {
      file.remove(full_filename)
    }
    save(
      measure,
      file = full_filename
    )
  }
  pc_sim
}