\Header{segments}{Add Line Segments to a Plot}
\keyword{aplot}{segments}
\begin{Description}\relax
Draw line segments between pairs of points.\end{Description}
\begin{Usage}
\begin{verbatim}
segments(x0, y0, x1, y1,
       col = par("fg"), lty = par("lty"), xpd = FALSE)
\end{verbatim}
\end{Usage}
\begin{Arguments}
\begin{ldescription}
\item[\code{x0,y0}] coordinates of points \bold{from} which to draw.
\item[\code{x1,y1}] coordinates of points \bold{to} which to draw.
\item[\code{length}] length of the edges of the arrow head (in inches).
\item[\code{angle}] angle from the shaft of the arrow to the edge of the arrow head.
\item[\code{col, lty, xpd}] usual graphical parameters as in \code{\Link{par}}.
\end{ldescription}
\end{Arguments}
\begin{Details}\relax
For each \code{i}, a line segment is drawn between the point \code{(x0[i],
    y0[i])} and the point \code{(x1[i],y1[i])}.

The graphical parameters \code{col} and \code{lty} can be used
to specify a color and line texture for the line segments (\code{col}
may be a vector).\end{Details}
\begin{SeeAlso}\relax
\code{\Link{arrows}}, 
\code{\Link{polygon}} for slightly easier and less flexible line drawing and
\code{\Link{lines}} for the usual polygons.\end{SeeAlso}
\begin{Examples}
\begin{ExampleCode}
x <- runif(12); y <- rnorm(12)
i <- order(x,y); x <- x[i]; y <- y[i]
plot(x,y, main="arrows(.) and segments(.)")
## draw arrows from point to point :
s <- seq(length(x)-1)# one shorter than data
arrows(x[s], y[s], x[s+1], y[s+1], col= 1:3)
s <- s[-length(s)]
segments(x[s], y[s], x[s+2], y[s+2], col= 'pink')
\end{ExampleCode}
\end{Examples}

