Pass the number of control and experimental treatments as attributes

DESCRIPTION

@@ -1,7 +1,7 @@
 Package: simtrial
 Type: Package
 Title: Clinical Trial Simulation
-Version: 0.4.1.9
+Version: 0.4.1.10
 Authors@R: c(
     person("Keaven", "Anderson", email = "[email protected]", role = c("aut")),
     person("Yujie", "Zhao", email = "[email protected]", role =  c("ctb","cre")),

R/counting_process.R

@@ -64,7 +64,10 @@
 #' @details
 #' The output produced by [counting_process()] produces a
 #' counting process dataset grouped by stratum and sorted within stratum
-#' by increasing times where events occur.
+#' by increasing times where events occur. The object is assigned the class
+#' "counting_process". It also has the attributes "control" and "experimental",
+#' which are the totals of the control and experimental treatments,
+#' respectively, from the input time-to-event data.
 #'
 #' @examples
 #' # Example 1
@@ -144,6 +147,10 @@ counting_process <- function(x, arm) {
 
   setDF(ans)
   class(ans) <- c("counting_process", class(ans))
+  # Record number of control and experimental treatments, which is required for
+  # downstream test function wlr()
+  attr(ans, "control") <- sum(x$treatment == "control")
+  attr(ans, "experimental") <- sum(x$treatment == "experimental")
 
   return(ans)
 }

R/wlr.R

@@ -112,7 +112,7 @@ wlr.counting_process <- function(data, weight, return_variance = FALSE) {
 
   # calculate the sample size and randomization ratio
   n <- nrow(data)
-  ratio <- sum(data$treatment == "experimental") / sum(data$treatment == "control")
+  ratio <- attr(data, "experimental") / attr(data, "control")
   q_e <- ratio / (1 + ratio)
   q_c <- 1 - q_e