Initial implementation of ebola args checker, WIP #173

R/check_args_ebola.R

@@ -0,0 +1,53 @@
+#' @title Prepare arguments to ebola model function
+#' @name prepare_ebola_args
+#' @rdname prepare_ebola_args
+#'
+#' @description Prepare arguments to [model_ebola()] for
+#' [.model_ebola_internal()].
+#'
+#' @param mod_args A named list of composable elements; must include a
+#' `<population>`.
+#'
+#' @return
+#' A list of model arguments suitable for [.model_ebola_internal()].
+#' This is a named list consisting of:
+#'
+#' **WIP**
+#'
+#' @keywords internal
+#' @details
+#' `.check_prepare_args_ebola()` prepares arguments for
+#' [.model_ebola_internal()], by converting some of the arguments
+#' collected in `mod_args` into simpler structures that are appropriate for the
+#' internal model function.
+.check_prepare_args_ebola <- function(mod_args) {
+  # prepare the initial conditions; accessed from prepared list
+  # NOTE: round to integer as this is a discrete-time model
+  initial_state <- round(
+    .prepare_population(
+      mod_args[["population"]]
+    )[["initial_state"]]
+  )
+
+  # check that rate interventions are on allowed targets
+  # NOTE: type `<rate_intervention>` is already checked at top level
+  # NOTE: `infectiousness_rate` and `removal_rate` are not allowed as they
+  # control the number of epidemiological sub-compartments, which cannot be
+  # safely changed while the model is running
+  intervention <- .cross_check_intervention(
+    mod_args[["intervention"]], mod_args[["population"]],
+    c(
+      "transmission_rate", "prop_community", "etu_risk", "funeral_risk"
+    )
+  )
+
+  # extract and provide time_dependence
+  time_dependence <- mod_args[["time_dependence"]]
+
+  # return selected arguments for internal function
+  list(
+    initial_state = initial_state,
+    intervention = intervention, # keep consistent naming
+    time_dependence = time_dependence
+  )
+}