stabler and faster C code for ME and BIONJ

[ape.git] / R / rtree.R

diff --git a/R/rtree.R b/R/rtree.R
index 6d0172c1ef8b5029739dbd91eb7d027064f1e37f..cba5d4e4a40c967dbbb443d30396ab7333913aef 100644 (file)
--- a/R/rtree.R
+++ b/R/rtree.R
@@ -1,4 +1,4 @@
-## rtree.R (2008-01-08)
+## rtree.R (2008-01-13)
 
 ##   Generates Random Trees
 
@@ -100,11 +100,13 @@ rtree <- function(n, rooted = TRUE, tip.label = NULL, br = runif, ...)
     phy
 }
 
-rcoal <- function(n, tip.label = NULL, br = rexp, ...)
+rcoal <- function(n, tip.label = NULL, br = "coalescent", ...)
 {
     nbr <- 2*n - 2
     edge <- matrix(NA, nbr, 2)
-    x <- br(n - 1, ...) # coalescence times
+    ## coalescence times by default:
+    x <- if (is.character(br)) 2*rexp(n - 1)/(n:2 * (n - 1):1)
+    else br(n - 1, ...)
     if (n == 2) {
         edge[] <- c(3, 3, 1:2)
         edge.length <- rep(x, 2)