\name{unpack}
\title{Full Storage Representation of Packed Matrices}
\usage{
unpack(x, \dots)
}
\alias{unpack}
\description{
  Expands decompositions stored in compact form into matrix factors.
}
\arguments{
  \item{x}{
    a matrix stored in packed form, e.g., of class \code{"d?pMatrix"}
    where "?" is "t" for triangular or "s" for symmetric.
  }
  \item{\dots}{further arguments passed to or from other methods.}
}
\value{
  A \code{Matrix} object containing the full-storage representation of
  \code{x}.
}
\details{
  This is a generic function with special methods for different types
  of packed matrices.  Use \code{\link{showMethods}("unpack")} to list
  the methods for \code{unpack()}.
}
\examples{
showMethods("unpack")
(cp4 <- chol(Hilbert(4))) # is triangular
tp4 <- as(cp4,"dtpMatrix")# [t]riangular [p]acked
str(tp4)
(unpack(tp4))

\dontrun{
## once we have Diagonal() :
unpack(Diagonal( 1:3))
}
}
\keyword{array}
\keyword{algebra}