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\name{writeMps}
\alias{writeMps}
\title{Write MPS Files}
\description{
This function writes MPS files - the standard format for Linear Programming problems.
}
\usage{
writeMps( file, cvec, bvec, Amat, name="LP" )
}
\arguments{
\item{file}{a character string naming the file to write.}
\item{cvec}{vector \eqn{c}.}
\item{bvec}{vector \eqn{b}.}
\item{Amat}{matrix \eqn{A}.}
\item{name}{an optional name for the Linear Programming problem.}
}
\details{
The exported LP can be solved by running other software on this MPS file
(e.g. \code{lp_solve}, see \url{http://lpsolve.sourceforge.net/5.5/}).
}
\author{Arne Henningsen}
\seealso{\code{\link{solveLP}}, \code{\link{readMps}}
}
\examples{
## example of Steinhauser, Langbehn and Peters (1992)
## Production activities
cvec <- c(1800, 600, 600) # gross margins
names(cvec) <- c("Cows","Bulls","Pigs")
## Constraints (quasi-fix factors)
bvec <- c(40, 90, 2500) # endowment
names(bvec) <- c("Land","Stable","Labor")
## Needs of Production activities
Amat <- rbind( c( 0.7, 0.35, 0 ),
c( 1.5, 1, 3 ),
c( 50, 12.5, 20 ) )
## Write to MPS file
writeMps( "steinh.mps", cvec, bvec, Amat, "Steinhauser" )
## remove the MPS file
file.remove( "steinh.mps" )
}
\keyword{ optimize }
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