R: Draw a Stick Plot

plotSticks {oce}

R Documentation

Draw a Stick Plot

Description

The arrows are drawn with directions on the graph that match the directions indicated by the u and 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 y. The interpretation of diagrams produced by plotSticks can be difficult, owing to overlap in the arrows. For this reason, it It is often a good idea to smooth u and v before using this function.

Usage

plotSticks(x, y, u, v, yscale = 1, add = FALSE, length = 1/20,
  mgp = getOption("oceMgp"), mar = c(mgp[1] + 1, mgp[1] + 1, 1, 1 +
  par("cex")), ...)

Arguments

`x`	x coordinates of stick origins.
`y`	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.
`u`	x component of stick length.
`v`	y component of stick length.
`yscale`	scale from u and v to y (see “Details”).
`add`	boolean, set `TRUE` to add to an existing plot.
`length`	value to be provided to `arrows`; here, we set a default that is smaller than normally used, because these plots tend to be crowded in oceanographic applications.
`mgp`	3-element numerical vector to use for `par(mgp)`, and also for `par(mar)`, computed from this. The default is tighter than the R default, in order to use more space for the data and less for the axes.
`mar`	value to be used with `par("mar")`.
`...`	graphical parameters passed down to `arrows`. It is common, for example, to use smaller arrow heads than `arrows` uses; see “Examples”.

Author(s)

Dan Kelley

Examples


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
if (require(ocedata)) {
    data(met)
    t <- ISOdatetime(met[["Year"]], met[["Month"]], met[["Day"]], 0, 0, 0, tz="UTC")
    u <- met[["u"]]
    v <- met[["v"]]
    temperature <- met[["temperature"]]
    oce.plot.ts(t, temperature, type='p', ylim=c(-5, 30))
    plotSticks(t, 5, u, v, yscale=2, add=TRUE)
}

[Package oce version 0.9-20 Index]