list(...)[c(<n1>, <n2>)] is never empty

git-svn-id: https://svn.r-project.org/R/trunk@88048 00db46b3-68df-0310-9c12-caf00c1e9a41

Author: maechler

src/library/stats/R/factanal.R

@@ -107,7 +107,9 @@ factanal <-
 
     cn <- list(nstart = 1, trace = FALSE, lower = 0.005)
     cn[names(control)] <- control
-    more <- list(...)[c("nstart", "trace", "lower", "opt", "rotate")]
+    more <- if(...length())
+                Filter(length, # drop NULL components in
+                       list(...)[c("nstart", "trace", "lower", "opt", "rotate")])
     if(length(more)) cn[names(more)] <- more
 
     if(is.null(start)) {