\name{qpSampleMvnorm} \alias{qpSampleMvnorm} \title{ Sample multivariate normal observations } \description{ Samples independent observations from a multivariate normal distribution with a given mean vector and a given concentration matrix. } \usage{ qpSampleMvnorm(K, N, mean = rep(0, nrow(K))) } \arguments{ \item{K}{concentration matrix of the multivariate normal distribution.} \item{N}{number of observations to sample.} \item{mean}{mean vector of the multivariate normal distribution.} } \details{ This function requires the \code{mvtnorm} package. This function is designed to be used to sample multivariate normal observations from a randomly generated concentration matrix that has a zero-structure reflecting the conditional independencies from a, possibly also randomly generated, undirected graph. The function \code{\link{qpI2K}} can be employed to obtain such a concentration matrix. } \value{ A matrix where rows correspond to observations and columns to random variables. } \references{ Castelo, R. and Roverato, A. A robust procedure for Gaussian graphical model search from microarray data with p larger than n. \emph{J. Mach. Learn. Res.}, 7:2621-2650, 2006. } \author{R. Castelo and A. Roverato} \seealso{ \code{\link{qpI2K}} } \examples{ nVar <- 50 # number of variables maxCon <- 5 # maximum connectivity per variable nObs <- 30 # number of observations to simulate I <- qpRndGraph(n.vtx=nVar, n.bd=maxCon) K <- qpI2K(I) X <- qpSampleMvnorm(K, nObs) dim(X) } \keyword{models} \keyword{multivariate}