# is.binary.tree

From ape v3.2
0th

Percentile

##### Test for Binary Tree

This function tests whether a phylogenetic tree is binary.

Keywords
logic
##### Usage
is.binary.tree(phy)
##### Arguments
phy
an object of class "phylo".
##### Details

The test differs slightly whether the tree is rooted or not. An urooted tree is considered binary if all its nodes are of degree three (i.e., three edges connect to each node). A rooted tree is considered binary if all nodes (including the root node) have exactly two descendant nodes, so that they are of degree three expect the root which is of degree 2.

##### Value

• is.binary.tree returns TRUE if tree is a fully binary phylogenetic tree, otherwise it returns FALSE.

is.rooted, is.ultrametric, multi2di

##### Aliases
• is.binary.tree
##### Examples
data("hivtree.newick") # example tree in NH format
plot(tree.hiv)