\HeaderA{plot.cor}{Red and Green Color Image of Correlation Matrix}{plot.cor}
\keyword{hplot}{plot.cor}
\begin{Description}\relax
This function produces a red and green color image of a correlation
matrix using an RGB color specification. Increasingly positive
correlations are represented with reds of increasing intensity, and
increasingly negative correlations are represented with greens of
increasing intensity.
\end{Description}
\begin{Usage}
\begin{verbatim}
plot.cor(x, new=FALSE, nrgcols=50, labels=FALSE, labcols=1, title="", ...)
\end{verbatim}
\end{Usage}
\begin{Arguments}
\begin{ldescription}
\item[\code{x}] a matrix of numerical values.
\item[\code{new}] If \code{new=F}, \code{X} must already be a correlation
matrix. If \code{new=T}, the correlation matrix for the columns of
\code{X} is computed and displayed in the image.
\item[\code{nrgcols}] the number of colors (>= 1) to be used in the red
and green palette.
\item[\code{labels}] vector of character strings to be placed at the
tickpoints, labels for the columns of \code{X}.
\item[\code{labcols}] colors to be used for the labels of the columns of
\code{X}. \code{labcols} can have either length 1, in which case
all the labels are displayed using the same color, or the same
length as \code{labels}, in which case a color is specified for the
label of each column of \code{X}.
\item[\code{title}] character string, overall title for the plot.
\item[\code{...}] graphical parameters may also be supplied as arguments to
the function (see \code{\LinkA{par}{par}}). For comparison purposes, 
it is good to set \code{zlim=c(-1,1)}.
\end{ldescription}
\end{Arguments}
\begin{Author}\relax
Sandrine Dudoit, \email{sandrine@stat.berkeley.edu}
\end{Author}
\begin{SeeAlso}\relax
\code{\LinkA{plot.mat}{plot.mat}},\code{\LinkA{rgcolors.func}{rgcolors.func}},
\code{\LinkA{cor.na}{cor.na}}, \code{\LinkA{cor}{cor}}, \code{\LinkA{image}{image}},
\code{\LinkA{rgb}{rgb}}.
\end{SeeAlso}

