1% Generated by roxygen2: do not edit by hand 2% Please edit documentation in R/make.R 3\name{make_line_graph} 4\alias{make_line_graph} 5\alias{line.graph} 6\alias{line_graph} 7\title{Line graph of a graph} 8\usage{ 9make_line_graph(graph) 10 11line_graph(...) 12} 13\arguments{ 14\item{graph}{The input graph, it can be directed or undirected.} 15 16\item{...}{Passed to \code{make_line_graph}.} 17} 18\value{ 19A new graph object. 20} 21\description{ 22This function calculates the line graph of another graph. 23} 24\details{ 25The line graph \code{L(G)} of a \code{G} undirected graph is defined as 26follows. \code{L(G)} has one vertex for each edge in \code{G} and two 27vertices in \code{L(G)} are connected by an edge if their corresponding 28edges share an end point. 29 30The line graph \code{L(G)} of a \code{G} directed graph is slightly 31different, \code{L(G)} has one vertex for each edge in \code{G} and two 32vertices in \code{L(G)} are connected by a directed edge if the target of 33the first vertex's corresponding edge is the same as the source of the 34second vertex's corresponding edge. 35} 36\examples{ 37 38# generate the first De-Bruijn graphs 39g <- make_full_graph(2, directed=TRUE, loops=TRUE) 40make_line_graph(g) 41make_line_graph(make_line_graph(g)) 42make_line_graph(make_line_graph(make_line_graph(g))) 43 44} 45\author{ 46Gabor Csardi \email{csardi.gabor@gmail.com}, the first version of 47the C code was written by Vincent Matossian. 48} 49\keyword{graphs} 50