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% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/plot.R
\name{network.arrow}
\alias{network.arrow}
\title{Add Arrows or Segments to a Plot}
\usage{
network.arrow(
x0,
y0,
x1,
y1,
length = 0.1,
angle = 20,
width = 0.01,
col = 1,
border = 1,
lty = 1,
offset.head = 0,
offset.tail = 0,
arrowhead = TRUE,
curve = 0,
edge.steps = 50,
...
)
}
\arguments{
\item{x0}{A vector of x coordinates for points of origin}
\item{y0}{A vector of y coordinates for points of origin}
\item{x1}{A vector of x coordinates for destination points}
\item{y1}{A vector of y coordinates for destination points}
\item{length}{Arrowhead length, in current plotting units}
\item{angle}{Arrowhead angle (in degrees)}
\item{width}{Width for arrow body, in current plotting units (can be a
vector)}
\item{col}{Arrow body color (can be a vector)}
\item{border}{Arrow border color (can be a vector)}
\item{lty}{Arrow border line type (can be a vector)}
\item{offset.head}{Offset for destination point (can be a vector)}
\item{offset.tail}{Offset for origin point (can be a vector)}
\item{arrowhead}{Boolean; should arrowheads be used? (Can be a vector))}
\item{curve}{Degree of edge curvature (if any), in current plotting units
(can be a vector)}
\item{edge.steps}{For curved edges, the number of steps to use in
approximating the curve (can be a vector)}
\item{\dots}{Additional arguments to \code{\link{polygon}}}
}
\value{
None.
}
\description{
\code{network.arrow} draws a segment or arrow between two pairs of points;
unlike \code{\link{arrows}} or \code{\link{segments}}, the new plot element
is drawn as a polygon.
}
\details{
\code{network.arrow} provides a useful extension of \code{\link{segments}}
and \code{\link{arrows}} when fine control is needed over the resulting
display. (The results also look better.) Note that edge curvature is
quadratic, with \code{curve} providing the maximum horizontal deviation of
the edge (left-handed). Head/tail offsets are used to adjust the end/start
points of an edge, relative to the baseline coordinates; these are useful
for functions like \code{\link{plot.network}}, which need to draw edges
incident to vertices of varying radii.
}
\note{
\code{network.arrow} is a direct adaptation of
\code{\link[sna]{gplot.arrow}} from the \code{sna} package.
}
\examples{
#Plot two points
plot(1:2,1:2)
#Add an edge
network.arrow(1,1,2,2,width=0.01,col="red",border="black")
}
\references{
Butts, C. T. (2008). \dQuote{network: a Package for Managing
Relational Data in R.} \emph{Journal of Statistical Software}, 24(2).
\doi{10.18637/jss.v024.i02}
}
\seealso{
\code{\link{plot.network}}, \code{\link{network.loop}},
\code{\link{polygon}}
}
\author{
Carter T. Butts \email{buttsc@uci.edu}
}
\keyword{aplot}
\keyword{graphs}
|
