+\name{alex}
+\alias{alex}
+\title{Alignment Explorer With Multiple Devices}
+\description{
+ This function helps to explore DNA alignments by zooming in. The user
+ clicks twice defining the opposite corners of the portion which is
+ extracted and drawned on a new window.
+}
+\usage{
+alex(x, ...)
+}
+\arguments{
+ \item{x}{an object of class \code{"DNAbin"}.}
+ \item{\dots}{further arguments to pass to \code{image.DNAbin}.}
+}
+\details{
+ This function works with a DNA alignment (freshly) plotted on an
+ interactive graphical device (i.e., not a file) with \code{image}.
+ After calling \code{alex}, the user clicks twice defining a rectangle
+ in the alignment, then this portion of the alignment is extacted and
+ plotted on a \emph{new} window. The user can click as many times on
+ the alignment. The process is stopped by a right-click. If the user
+ clicks twice outside the alignment, a message ``Try again!'' is
+ printed.
+
+ Each time \code{alex} is called, the alignment is plotted on a new
+ window without closing or deleting those possibly already plotted.
+
+ In all cases, the device where \code{x} is plotted is the active
+ window after the operation. It should \emph{not} be closed during the
+ whole process.
+}
+\value{NULL}
+\author{Emmanuel Paradis}
+\seealso{
+ \code{\link{image.DNAbin}}, \code{\link{trex}}
+}
+\examples{
+\dontrun{
+data(woodmouse)
+image(woodmouse)
+alex(woodmouse)
+}}
+\keyword{hplot}