The arrows are drawn with directions on the graph that match the directions
indicated by the
v components. The arrow size is set
relative to the units of the
y axis, according to the value of
yscale, which has the unit of
v divided by the unit of
The interpretation of diagrams produced by
plotSticks can be
difficult, owing to overlap in the arrows. For this reason, it is often
a good idea to smooth
v before using this function.
plotSticks( x, y, u, v, yscale = 1, add = FALSE, length = 1/20, mgp = getOption("oceMgp"), mar = c(mgp + 1, mgp + 1, 1, 1 + par("cex")), xlab = "", ylab = "", col = 1, ... )
x coordinates of stick origins.
y coordinates of stick origins. If not supplied, 0 will be used; if length is less than that of x, the first number is repeated and the rest are ignored.
x component of stick length.
y component of stick length.
scale from u and v to y (see “Description”).
value to be provided to
3-element numerical vector to use for
value to be used with
labels for the plot axes. The default is not to label them.
color of sticks, in either numerical or character format. This is
made to have length matching that of
library(oce) # Flow from a point source n <- 16 x <- rep(0, n) y <- rep(0, n) theta <- seq(0, 2*pi, length.out=n) u <- sin(theta) v <- cos(theta) plotSticks(x, y, u, v, xlim=c(-2, 2), ylim=c(-2, 2))rm(n, x, y, theta, u, v) # Oceanographic example data(met) t <- met[["time"]] u <- met[["u"]] v <- met[["v"]] p <- met[["pressure"]] oce.plot.ts(t, p)plotSticks(t, 99, u, v, yscale=25, add=TRUE)