\name{externalMatrix}
\alias{externalMatrix}
\title{ Create an external matrix object }
\description{
  This function can be used to create a new external matrix object.
}
\usage{
externalMatrix(data = NA, nrow = 1, ncol = 1, byrow = FALSE, dimnames =
NULL, storageClass = (if (is(data, "externalVectorWithStorage"))
class(data@storage) else "simpleStorage"), indirect = FALSE)
}
%- maybe also 'usage' for other objects documented here.
\arguments{
  \item{data}{ An optional data vector. }
  \item{nrow}{ The desired number of rows. }
  \item{ncol}{ The desired number of columns. }
  \item{byrow}{ Not used. }
%  \item{byrow}{ Logical. If 'FALSE' (the default) the matrix is filled by
%          columns, otherwise the matrix is filled by rows. }
  \item{dimnames}{ A \code{dimnames} value for the external matrix: a
    \code{list} of length 2. }
  \item{storageClass}{ name of the subclass of "externalStorage" to be
    used for storing the external vector elements. }
  \item{indirect}{ If \code{TRUE}, return an
    "indirectExternalVector" object. }
}
\details{
  This function is similar to the \code{matrix} function in \R base package.
}
\value{
  If \code{indirect} is \code{FALSE} (the default)
  a new external matrix object with correct dimension and dimnames.
  Otherwise create a new external vector object but return it by
  wrapping it in an "indirectExternalMatrix" object with the correct
  dimension and dimnames.
}
\seealso{ \code{\link{matrix}} }
\examples{
x <- externalMatrix(1:6, nrow=2, ncol=3)
dim(x)
x[1, 1:2] # drop = FALSE by default
log(x)
}
\keyword{ array }