castor (version 1.8.2)

count_tips_per_node: Count descending tips.

Description

Given a rooted phylogenetic tree, count the number of tips descending (directy or indirectly) from each node.

Usage

count_tips_per_node(tree)

Value

An integer vector of size Nnodes, with the i-th entry being the number of tips descending (directly or indirectly) from the i-th node.

Arguments

tree

A rooted tree of class "phylo". The root is assumed to be the unique node with no incoming edge.

Author

Stilianos Louca

Details

The asymptotic time complexity of this function is O(Nedges), where Nedges is the number of edges.

See Also

get_subtree_at_node

Examples

# generate a tree using a simple speciation model 
tree = generate_random_tree(list(birth_rate_intercept=1),max_tips=1000)$tree

# count number of tips descending from each node
tips_per_node = count_tips_per_node(tree);

# plot histogram of tips-per-node
barplot(table(tips_per_node[tips_per_node<10]), xlab="# tips", ylab="# nodes")