Merge branch 'issue-369': closes #369 by cherry picking the commit from the 2.5 branch

Author: gavinsimpson

R/permutest.betadisper.R

@@ -93,8 +93,15 @@
             if (!hasClus) {
                 parallel <- makeCluster(parallel)
             }
-            Pstats <- parRapply(parallel, permutations,
-                                          function(x) permFun(x))
+
+            Pstats <- parApply(parallel, permutations, 1,
+                               function(x) permFun(x))
+            if (is.null(dim(Pstats))) {
+                Pstats <- matrix(Pstats) # one-column matrix
+            } else {
+                Pstats <- t(Pstats) # transpose statistics to columns
+            }
+
             if (!hasClus) {
                 stopCluster(parallel)
             }
@@ -105,7 +112,7 @@
 
     ## Process results
     F0 <- summary(mod)$fstatistic[1]
-    Fstats <- Pstats[, 1]    # allow empty dim to be dropped
+    Fstats <- Pstats[, 1, drop = TRUE]    # allow empty dim to be dropped
     statistic <- F0
     names(statistic) <- "Overall (F)"