\name{plotParallel}
\alias{plotParallel}
\title{ Plot a Parallel Analysis Class Object }

\description{
}

\usage{
plotParallel(parallel,
eig    = NA,
x      = eig,
model  = "components",
legend = TRUE,
ylab   = "Eigenvalues",
xlab   = "Components",
main   = "Parallel Analysis",
...
)
}

\arguments{
\item{parallel}{ numeric:   vector of the results of a previous parallel analysis }
\item{eig}{      depreciated parameter: eigenvalues to analyse (not used if
x is used, recommended)}
\item{x}{        numeric: a \code{vector} of eigenvalues, a \code{matrix} of
correlations or of covariances or a \code{data.frame} of data}
\item{model}{    character: \code{"components"} or \code{"factors"} }
\item{main}{     character: title of the plot }
\item{xlab}{     character: label of the x axis }
\item{ylab}{     character: label of the y axis }
\item{legend}{   logical:   indicator of the presence or not of a legend }
\item{...}{      variable: additionnal parameters to give to the \code{cor} or
\code{cov} functions}
}

\details{
If \code{eig} is \code{FALSE} the plot shows only the parallel analysis without eigenvalues.
}

\value{
Nothing returned.
}

\references{
Raiche, G., Riopel, M. and Blais, J.-G. (2006). \emph{Non graphical solutions for the Cattell's scree test}.
Paper presented at the International Annual meeting of the Psychometric Society, Montreal.
[\url{http://www.er.uqam.ca/nobel/r17165/RECHERCHE/COMMUNICATIONS/}]
}

\author{
Gilles Raiche \cr
Centre sur les Applications des Modeles de Reponses aux Items (CAMRI) \cr
Universite du Quebec a Montreal\cr
\email{raiche.gilles@uqam.ca}, \url{http://www.er.uqam.ca/nobel/r17165/}
}

\seealso{
}

\examples{
## SIMPLE EXAMPLE OF A PARALLEL ANALYSIS
## OF A CORRELATION MATRIX WITH ITS PLOT
data(dFactors)
eig      <- dFactors$Raiche$eigenvalues
subject  <- dFactors$Raiche$nsubjects
var      <- length(eig)
rep      <- 100
cent     <- 0.95
results  <- parallel(subject,var,rep,cent)

results

## PARALLEL ANALYSIS SCREE PLOT
plotParallel(results, x=eig)
plotParallel(results)

}

\keyword{ Graphics }