Merge pull request #509 from yihui/char-for-fun

Allow bound functions and spending functions to take character values

Author: LittleBeannie

NEWS.md

@@ -1,3 +1,9 @@
+# gsDesign2 1.1.4
+
+## User interface improvements
+
+- Bound functions and spending functions can be provided through their names (character strings) now, e.g., `gs_design_ahr(..., upper = "gs_spending_bound", upar = list(sf = "sfLDOF", ...))` (#509, thanks to @yihui).
+
 # gsDesign2 1.1.3
 
 ## Bug fixes

R/gs_design_ahr.R

@@ -229,6 +229,8 @@ gs_design_ahr <- function(
     info_frac <- 1
   }
   info_scale <- match.arg(info_scale)
+  upper <- match.fun(upper)
+  lower <- match.fun(lower)
 
   # Check inputs ----
   check_analysis_time(analysis_time)
@@ -243,7 +245,7 @@ gs_design_ahr <- function(
   # Check if alpha is same as alpha spending ----
   if (identical(upper, gs_spending_bound)) {
     if (!is.null(upar$total_spend)) {
-      if (methods::missingArg(alpha)) {
+      if (missing(alpha)) {
         alpha <- upar$total_spend
       } else {
         if (alpha != upar$total_spend) {

R/gs_design_npe.R

@@ -275,6 +275,8 @@ gs_design_npe <- function(
   check_theta(theta0, n_analysis)
   check_theta(theta1, n_analysis)
 
+  upper <- match.fun(upper)
+  lower <- match.fun(lower)
   # check test_upper & test_lower
   if (length(test_upper) == 1 && n_analysis > 1) test_upper <- rep(test_upper, n_analysis)
   if (length(test_lower) == 1 && n_analysis > 1) test_lower <- rep(test_lower, n_analysis)

R/gs_power_npe.R

@@ -243,6 +243,8 @@ gs_power_npe <- function(theta = .1, theta0 = NULL, theta1 = NULL, # 3 theta
   } else if (length(theta1) == 1) {
     theta1 <- rep(theta1, n_analysis)
   }
+  upper <- match.fun(upper)
+  lower <- match.fun(lower)
   if (length(test_upper) == 1 && n_analysis > 1) test_upper <- rep(test_upper, n_analysis)
   if (length(test_lower) == 1 && n_analysis > 1) test_lower <- rep(test_lower, n_analysis)
 

R/gs_spending_bound.R

@@ -121,7 +121,13 @@ gs_spending_bound <- function(k = 1,
   }
 
   # Compute cumulative spending at each analyses ----
-  spend <- par$sf(alpha = par$total_spend, t = timing, param = par$param)$spend
+  if (!is.function(sf <- par$sf)) sf <- tryCatch(match.fun(sf), error = function(e) {
+    # in case gsDesign is not attached (i.e. library(gsDesign)) or the spending
+    # function is not imported into gsDesign2 from gsDesign, we will get it from
+    # gsDesign's namespace
+    getExportedValue('gsDesign', sf)
+  })
+  spend <- sf(alpha = par$total_spend, t = timing, param = par$param)$spend
 
   # Compute incremental spending at each analyses ----
   old_spend <- 0