Add input validation to estimators

1 files changed, 55 insertions, 0 deletions

diff --git a/R/util.R b/R/util.R
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index 0000000..d8b0b59
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+++ b/R/util.R
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+#' Case Counts Validation
+#'
+#' This is an internal function called by the estimators. It validates the
+#' supplied case counts by ensuring it is a vector of integers of length at
+#' least `min_length` with entries greater than or equal to `min_count`.
+#' Execution is halted if these requirements are not satisfied.
+#'
+#' @param cases The case counts to be validated.
+#' @param min_length The minimum length of the vector of case counts.
+#' @param min_count The minimum value of the case count vector's entries.
+#'
+#' @noRd
+validate_cases <- function(cases, min_length, min_count) {
+  if (!is.vector(cases) || !is.numeric(cases) || any(floor(cases) != cases)) {
+    stop("Case counts must be a vector of integers.", call. = FALSE)
+  }
+  if (length(cases) < min_length) {
+    stop(paste("Case counts must have at least", min_length, "entries."),
+      call. = FALSE
+    )
+  }
+  if (any(cases < min_count)) {
+    stop(paste0("Case counts cannot be less than ", min_count, "."),
+      call. = FALSE
+    )
+  }
+}
+
+#' Real Number Testing
+#'
+#' This is an internal function which checks whether the given argument is a
+#' real number.
+#'
+#' @param x The argument to test for being a real number.
+#'
+#' @return `TRUE` if the argument is a real number, `FALSE` otherwise.
+#'
+#' @noRd
+is_real <- function(x) {
+  is.vector(x) && is.numeric(x) && length(x) == 1
+}
+
+#' Integer Testing
+#'
+#' This is an internal function which checks whether the given argument is an
+#' integer.
+#'
+#' @param n The argument to test for being an integer.
+#'
+#' @return `TRUE` if the argument is an integer, `FALSE` otherwise.
+#'
+#' @noRd
+is_integer <- function(n) {
+  is_real(n) && floor(n) == n
+}