is.binary {ape} | R Documentation

## Test for Binary Tree

### Description

This function tests whether a phylogenetic tree is binary.

### Usage

    is.binary(phy)
    ## S3 method for class 'phylo'
    is.binary(phy)
    ## S3 method for class 'multiPhylo'
    is.binary(phy)
    ## S3 method for class 'tree'
    is.binary(phy)

### Arguments

`phy` | an object of class `"phylo"` or `"multiPhylo"`.

### Details

The test differs 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.

`is.binary.tree` is deprecated and will be removed soon: currently it calls `is.binary`.

### Value

a logical vector.

### Author(s)

Emmanuel Paradis

### See Also

`is.rooted`, `is.ultrametric`, `multi2di`

### Examples

    is.binary(rtree(10))
    is.binary(rtree(10, rooted = FALSE))
    is.binary(stree(10))
    x <- setNames(rmtree(10, 10), LETTERS[1:10])
    is.binary(x)

[Package ape version 4.0 Index]