1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
|
\name{leaves}
\alias{leaves}
\alias{leaves,graph-method}
\title{Find the leaves of a graph}
\description{
A leaf of an undirected graph is a node with degree equal to one. A
leaf of a directed graph is defined with respect to in-degree or
out-degree. The leaves of a directed graph with respect to in-degree
(out-degree) are those nodes with in-degree (out-degree) equal to
zero.
}
\usage{
leaves(object, degree.dir)
}
\arguments{
\item{object}{A \code{graph} object}
\item{degree.dir}{One of \code{"in"} or \code{"out"}. This argument
is ignored when \code{object} is undirected and required otherwise.
When \code{degree.dir="in"} (\code{degree.dir="out"}), nodes have no
in coming (out going) edges will be returned. }
}
\value{
A character vector giving the node labels of the leaves.
}
\author{Seth Falcon}
\examples{
data(graphExamples)
graphExamples[[1]]
leaves(graphExamples[[1]])
data(apopGraph)
leaves(apopGraph, "in")
leaves(apopGraph, "out")
}
|
