clickdist.Rd
\name{clickdist}
\alias{clickdist}
\title{Interactively Measure Distance}
\description{
Measures the distance between two points
which the user has clicked on.
}
\usage{
clickdist()
}
\value{
A single nonnegative number.
}
\details{
This function allows the user to measure the distance
between two spatial locations, interactively,
by clicking on the screen display.
When \code{clickdist()} is called, the user is expected to
click two points in the current graphics device. The distance
between these points will be returned.
This function uses the \R{} command \code{\link[graphics]{locator}} to
input the mouse clicks. It only works on screen devices such as
\sQuote{X11}, \sQuote{windows} and \sQuote{quartz}.
}
\seealso{
\code{\link[graphics]{locator}},
\code{\link{clickppp}},
\code{\link{clicklpp}},
\code{\link{clickpoly}},
\code{\link{clickbox}}
}
\author{
\spatstatAuthors.
}
\keyword{spatial}
\keyword{iplot}