castor (version 1.6.1)

tree_from_branching_ages: Generate a random timetree with specific branching ages.

Description

Generate a random timetree based on specific branching ages (time before present), by randomly connecting tips and nodes. The tree's root will have the greatest age provided. The tree thus corresponds to a homogenous birth-death model, i.e. where at any given time point all lineages were equally likely to split or go extinct.

Usage

tree_from_branching_ages(   branching_ages,
                            tip_basename       = "",
                            node_basename      = NULL,
                            edge_basename      = NULL)

Arguments

branching_ages

Integer vector of size Nnodes, listing branching ages (time before present) in ascending order. The last entry will be the root age.

tip_basename

Character. Prefix to be used for tip labels (e.g. "tip."). If empty (""), then tip labels will be integers "1", "2" and so on.

node_basename

Character. Prefix to be used for node labels (e.g. "node."). If NULL, no node labels will be included in the tree.

edge_basename

Character. Prefix to be used for edge labels (e.g. "edge."). Edge labels (if included) are stored in the character vector edge.label. If NULL, no edge labels will be included in the tree.

Value

A named list with the following elements:

success

Logical, indicating whether the tree was successfully generated. If FALSE, the only other value returned is error.

tree

A rooted, ultrametric bifurcating tree of class "phylo", with the requested branching ages.

error

Character, containing an explanation of ther error that occurred. Only included if success==FALSE.

Details

Tips in the generated tree are guaranteed to be connected in random order, i.e. this function can also be used to connect a random set of labeled tips into a tree. Nodes will be indexed in chronological order (i.e. in order of decreasing age). In particular, node 0 will be the root.

Examples

# NOT RUN {
Nnodes              = 100
branching_intervals = rexp(n=Nnodes, rate=1)
branching_ages      = cumsum(branching_intervals)
tree                = castor::tree_from_branching_ages(branching_ages)$tree
# }