# all.equal.phylo

##### Global Comparison of two Phylogenies

This function makes a global comparison of two phylogenetic trees.

- Keywords
- manip

##### Usage

```
# S3 method for phylo
all.equal(target, current, use.edge.length = TRUE,
use.tip.label = TRUE, index.return = FALSE,
tolerance = .Machine$double.eps ^ 0.5,
scale = NULL, …)
```

##### Arguments

- target
an object of class

`"phylo"`

.- current
an object of class

`"phylo"`

.- use.edge.length
if

`FALSE`

only the topologies are compared; the default is`TRUE`

.- use.tip.label
if

`FALSE`

the unlabelled trees are compared; the default is`TRUE`

.- index.return
if

`TRUE`

the function returns a two-column matrix giving the correspondence between the nodes of both trees.- tolerance
the numeric tolerance used to compare the branch lengths.

- scale
a positive number, comparison of branch lengths is made after scaling (i.e., dividing) them by this number.

- …
further arguments passed to or from other methods.

##### Details

This function is meant to be an adaptation of the generic function
`all.equal`

for the comparison of phylogenetic trees.

A single phylogenetic tree may have several representations in the Newick
format and in the `"phylo"`

class of objects used in `ape'. One
aim of the present function is to be able to identify whether two
objects of class `"phylo"`

represent the same phylogeny.

##### Value

A logical value, or a two-column matrix.

##### Note

The algorithm used here does not work correctly for the comparison of
topologies (i.e., ignoring tip labels) of unrooted trees. This also
affects `unique.multiPhylo`

which calls the present function. See:

http://www.mail-archive.com/r-sig-phylo@r-project.org/msg01445.html.

##### See Also

`all.equal`

for the generic R function

##### Examples

```
# NOT RUN {
### maybe the simplest example of two representations
### for the same rooted tree...:
t1 <- read.tree(text = "(a:1,b:1);")
t2 <- read.tree(text = "(b:1,a:1);")
all.equal(t1, t2)
### ... compare with this:
identical(t1, t2)
### one just slightly more complicated...:
t3 <- read.tree(text = "((a:1,b:1):1,c:2);")
t4 <- read.tree(text = "(c:2,(a:1,b:1):1);")
all.equal(t3, t4) # == all.equal.phylo(t3, t4)
### ... here we force the comparison as lists:
all.equal.list(t3, t4)
# }
```

*Documentation reproduced from package ape, version 4.1, License: GPL (>= 2)*