-## dist.topo.R (2010-01-22)
+## dist.topo.R (2010-01-25)
## Topological Distances, Tree Bipartitions,
## Consensus Trees, and Bootstrapping Phylogenies
if (method == "score" && (is.null(x$edge.length) || is.null(y$edge.length)))
stop("trees must have branch lengths for Billera et al.'s distance.")
nx <- length(x$tip.label)
+ x <- unroot(x)
+ y <- unroot(y)
bp1 <- .Call("bipartition", x$edge, nx, x$Nnode, PACKAGE = "ape")
bp1 <- lapply(bp1, function(xx) sort(x$tip.label[xx]))
ny <- length(y$tip.label) # fix by Otto Cordero