\name{drop.tip}
\alias{drop.tip}
+\alias{extract.clade}
\title{Remove Tips in a Phylogenetic Tree}
\usage{
drop.tip(phy, tip, trim.internal = TRUE, subtree = FALSE,
root.edge = 0)
+extract.clade(phy, node, root.edge = 0)
}
\arguments{
\item{phy}{an object of class \code{"phylo"}.}
\item{root.edge}{an integer giving the number of internal branches to
be used to build the new root edge. This has no effect if
\code{trim.internal = FALSE}.}
+ \item{node}{a node number or label.}
}
\description{
- This function removes the terminal branches of a phylogenetic tree,
+ \code{drop.tip} removes the terminal branches of a phylogenetic tree,
possibly removing the corresponding internal branches.
+
+ \code{extract.clade} does the inverse operation: it keeps all the tips
+ from a given node, and deletes all the other tips.
}
\details{
The argument \code{tip} can be either character or numeric. In the
second case the numbers of these labels in the vector
\code{phy$tip.label} are given.
+ This also applies to \code{node}, but if this argument is character
+ and the tree has no node label, this results in an error. If more than
+ one value is given with \code{node} (i.e., a vector of length two or
+ more), only the first one is used with a warning.
+
If \code{trim.internal = FALSE}, the new tips are given \code{"NA"} as
labels, unless there are node labels in the tree in which case they
are used.