-## rtree.R (2008-01-08)
+## rtree.R (2010-03-09)
-## Generates Random Trees
+## Generates Trees
-## Copyright 2004-2008 Emmanuel Paradis
+## Copyright 2004-2010 Emmanuel Paradis
## This file is part of the R-package `ape'.
## See the file ../COPYING for licensing issues.
n2 <- n - n1
po2 <- pos + 2*n1 - 1
edge[c(pos, po2), 1] <<- nod
- nod <<- nod + 1
+ nod <<- nod + 1L
if (n1 > 2) {
edge[pos, 2] <<- nod
foo(n1, pos + 1)
} else if (n1 == 2) {
edge[c(pos + 1, pos + 2), 1] <<- edge[pos, 2] <<- nod
- nod <<- nod + 1
+ nod <<- nod + 1L
}
if (n2 > 2) {
edge[po2, 2] <<- nod
foo(n2, po2 + 1)
} else if (n2 == 2) {
edge[c(po2 + 1, po2 + 2), 1] <<- edge[po2, 2] <<- nod
- nod <<- nod + 1
+ nod <<- nod + 1L
}
}
if (n < 2) stop("a tree must have at least 2 tips.")
- nbr <- 2 * n - 2
- if (!rooted) nbr <- nbr - 1
+ nbr <- 2 * n - 3 + rooted
edge <- matrix(NA, nbr, 2)
+ n <- as.integer(n)
if (n == 2) {
- if (rooted) edge[] <- c(3, 3, 1, 2)
+ if (rooted) edge[] <- c(3L, 3L, 1L, 2L)
else stop("an unrooted tree must have at least 3 tips.")
} else if (n == 3) {
edge[] <-
- if (rooted) c(4, 5, 5, 4, 5, 1:3)
- else c(4, 4, 4, 1:3)
+ if (rooted) c(4L, 5L, 5L, 4L, 5L, 1:3)
+ else c(4L, 4L, 4L, 1:3)
} else if (n == 4 && !rooted) {
- edge[] <- c(5, 6, 6, 5, 5, 6, 1:4)
+ edge[] <- c(5L, 6L, 6L, 5L, 5L, 6L, 1:4)
} else {
- nod <- n + 1
+ nod <- n + 1L
if (rooted) { # n > 3
foo(n, 1)
## The following is slightly more efficient than affecting the
foo(n1, 2)
} else if (n1 == 2) {
edge[2:3, 1] <- edge[1, 2] <- nod
- nod <- nod + 1
+ nod <- nod + 1L
}
if (n2 > 2) {
edge[po2, 2] <- nod
foo(n2, po2 + 1)
} else if (n2 == 2) {
edge[c(po2 + 1, po2 + 2), 1] <- edge[po2, 2] <- nod
- nod <- nod + 1
+ nod <- nod + 1L
}
if (n3 > 2) {
edge[po3, 2] <- nod
foo(n3, po3 + 1)
} else if (n3 == 2) {
edge[c(po3 + 1, po3 + 2), 1] <- edge[po3, 2] <- nod
- ## nod <- nod + 1
+ ## nod <- nod + 1L
}
i <- which(is.na(edge[, 2]))
edge[i, 2] <- 1:n
phy$tip.label <-
if (is.null(tip.label)) paste("t", sample(n), sep = "")
else sample(tip.label)
- if (is.function(br)) phy$edge.length <- br(nbr, ...)
- phy$Nnode <- if (rooted) n - 1 else n - 2
+ if (!is.null(br)) {
+ phy$edge.length <-
+ if (is.function(br)) br(nbr, ...) else rep(br, length.out = nbr)
+ }
+ phy$Nnode <- n - 2L + rooted
class(phy) <- "phylo"
phy
}
-rcoal <- function(n, tip.label = NULL, br = rexp, ...)
+rcoal <- function(n, tip.label = NULL, br = "coalescent", ...)
{
+ n <- as.integer(n)
nbr <- 2*n - 2
edge <- matrix(NA, nbr, 2)
- x <- br(n - 1, ...) # coalescence times
+ ## coalescence times by default:
+ x <- if (is.character(br)) 2*rexp(n - 1)/(as.double(n:2) * as.double((n - 1):1))
+ else if (is.numeric(br)) rep(br, length.out = n - 1) else br(n - 1, ...)
if (n == 2) {
- edge[] <- c(3, 3, 1:2)
+ edge[] <- c(3L, 3L, 1:2)
edge.length <- rep(x, 2)
} else if (n == 3) {
- edge[] <- c(4, 5, 5, 4, 5, 1:3)
- edge.length <- c(x[2], x[1], x[1], sum(x))
+ edge[] <- c(4L, 5L, 5L, 4L, 5L, 1:3)
+ edge.length <- c(x[c(2, 1, 1)], sum(x))
} else {
edge.length <- numeric(nbr)
h <- numeric(2*n - 1) # initialized with 0's
node.height <- cumsum(x)
pool <- 1:n
- nextnode <- 2*n - 1
+ nextnode <- 2L*n - 1L
for (i in 1:(n - 1)) {
y <- sample(pool, size = 2)
ind <- (i - 1)*2 + 1:2
edge.length[ind] <- node.height[i] - h[y]
h[nextnode] <- node.height[i]
pool <- c(pool[! pool %in% y], nextnode)
- nextnode <- nextnode - 1
+ nextnode <- nextnode - 1L
}
}
phy <- list(edge = edge, edge.length = edge.length)
- phy$tip.label <-
- if (is.null(tip.label)) paste("t", 1:n, sep = "")
- else tip.label
- phy$Nnode <- n - 1
+ if (is.null(tip.label))
+ tip.label <- paste("t", 1:n, sep = "")
+ phy$tip.label <- sample(tip.label)
+ phy$Nnode <- n - 1L
class(phy) <- "phylo"
- ##reorder(phy)
+ phy <- reorder(phy)
## to avoid crossings when converting with as.hclust:
- read.tree(text = write.tree(phy))
+ phy$edge[phy$edge[, 2] <= n, 2] <- 1:n
+ phy
}
rmtree <- function(N, n, rooted = TRUE, tip.label = NULL, br = runif, ...)
class(a) <- "multiPhylo"
a
}
+
+stree <- function(n, type = "star", tip.label = NULL)
+{
+ type <- match.arg(type, c("star", "balanced", "left", "right"))
+ n <- as.integer(n)
+ if (type == "star") {
+ N <- n
+ m <- 1L
+ } else {
+ m <- n - 1L
+ N <- n + m - 1L
+ }
+ edge <- matrix(0L, N, 2)
+
+ switch(type, "star" = {
+ edge[, 1] <- n + 1L
+ edge[, 2] <- 1:n
+ }, "balanced" = {
+ if (log2(n) %% 1)
+ stop("'n' is not a power of 2: cannot make a balanced tree")
+ foo <- function(node, size) {
+ if (size == 2) {
+ edge[c(i, i + 1L), 1L] <<- node
+ edge[c(i, i + 1L), 2L] <<- c(nexttip, nexttip + 1L)
+ nexttip <<- nexttip + 2L
+ i <<- i + 2L
+ } else {
+ for (k in 1:2) { # do the 2 subclades
+ edge[i, ] <<- c(node, nextnode)
+ nextnode <<- nextnode + 1L
+ i <<- i + 1L
+ foo(nextnode - 1L, size/2)
+ }
+ }
+ }
+ i <- 1L
+ nexttip <- 1L
+ nextnode <- n + 2L
+ foo(n + 1L, n)
+ }, "left" = {
+ edge[c(seq.int(from = 1, to = N - 1, by = 2), N), 2L] <- 1:n
+ nodes <- (n + 1L):(n + m)
+ edge[seq.int(from = 2, to = N - 1, by = 2), 2L] <- nodes[-1]
+ edge[, 1L] <- rep(nodes, each = 2)
+ }, "right" = {
+ nodes <- (n + 1L):(n + m)
+ edge[, 1L] <- c(nodes, rev(nodes))
+ edge[, 2L] <- c(nodes[-1], 1:n)
+ })
+
+ if (is.null(tip.label))
+ tip.label <- paste("t", 1:n, sep = "")
+ phy <- list(edge = edge, tip.label = tip.label, Nnode = m)
+ class(phy) <- "phylo"
+ attr(phy, "order" <- "cladewise")
+ phy
+}