\HeaderA{plot.xy}{Basic Internal Plot Function}{plot.xy}
\keyword{aplot}{plot.xy}
\begin{Description}\relax
This is \emph{the} internal function that does the basic plotting of
points and lines.  Usually, one should rather use the higher level
functions instead and refer to their help pages for explanation of the
arguments.
\end{Description}
\begin{Usage}
\begin{verbatim}
plot.xy(xy, type, pch = par("pch"), lty = par("lty"),
        col = par("col"), bg = NA,
        cex = 1, lwd = par("lwd"), ...)
\end{verbatim}
\end{Usage}
\begin{Arguments}
\begin{ldescription}
\item[\code{xy}] A four-element list as results from
\code{\LinkA{xy.coords}{xy.coords}}.
\item[\code{type}] 1 character code: see \code{\LinkA{plot.default}{plot.default}}.
\code{NULL} is accepted as a synonym for \code{"p"}.
\item[\code{pch}] character or integer code for kind of points, see
\code{\LinkA{points.default}{points.default}}.
\item[\code{lty}] line type code, see \code{\LinkA{lines}{lines}}.
\item[\code{col}] color code or name, see \code{\LinkA{colors}{colors}},
\code{\LinkA{palette}{palette}}.  Here \code{NULL} means colour 0.
\item[\code{bg}] background (fill) color for the open plot symbols 21:25:
see \code{\LinkA{points.default}{points.default}}.
\item[\code{cex}] character expansion.
\item[\code{lwd}] line width, also used for (non-filled) plot symbols, see
\code{\LinkA{lines}{lines}} and \code{\LinkA{points}{points}}.
\item[\code{...}] further graphical parameters such as \code{xpd},
\code{lend}, \code{ljoin} and \code{lmitre}.
\end{ldescription}
\end{Arguments}
\begin{Details}\relax
The arguments \code{pch, col, bg, cex, lwd} may be vectors and
may be recycled, depending on \code{type}: see \code{\LinkA{points}{points}} and
\code{\LinkA{lines}{lines}} for specifics.  In particular note that \code{lwd}
is treated as a vector for points and as a single (first) value for
lines.

\code{cex} is a numeric factor in addition to \code{par("cex")} which
affects symbols and characters as drawn by \code{type} \code{"p"},
\code{"o"}, \code{"b"} and \code{"c"}.
\end{Details}
\begin{SeeAlso}\relax
\code{\LinkA{plot}{plot}},
\code{\LinkA{plot.default}{plot.default}},
\code{\LinkA{points}{points}},
\code{\LinkA{lines}{lines}}.
\end{SeeAlso}
\begin{Examples}
\begin{ExampleCode}
points.default # to see how it calls "plot.xy(xy.coords(x, y), ...)"
\end{ExampleCode}
\end{Examples}

