\HeaderA{alphablend}{Alphablending for colors}{alphablend}
\keyword{color}{alphablend}
%
\begin{Description}\relax
Convert colors to semitransparent colors.
\end{Description}
%
\begin{Usage}
\begin{verbatim}
alphablend(col, alpha = NULL, bg = NULL)
\end{verbatim}
\end{Usage}
%
\begin{Arguments}
\begin{ldescription}
\item[\code{col}] a vector specifying colors.
\item[\code{alpha}] a numeric vector containing the alpha values (between 0 
and 1).
\item[\code{bg}] the background color to be used for alphablending.  This can 
be used as a workaround for graphics devices that do not support 
semitransparent colors.
\end{ldescription}
\end{Arguments}
%
\begin{Value}
a vector containing the semitransparent colors.
\end{Value}
%
\begin{Author}\relax
Andreas Alfons
\end{Author}
%
\begin{Examples}
\begin{ExampleCode}
alphablend("red", 0.6)
\end{ExampleCode}
\end{Examples}
