Adds isopycnal lines to an existing temperature-salinity plot. This is called by plotTS(), and may be called by the user also, e.g. if an image plot is used to show TS data density.

drawIsopycnals(
nlevels = 6,
levels,
rotate = TRUE,
rho1000 = FALSE,
digits = 2,
eos = getOption("oceEOS", default = "gsw"),
cex = 0.75 * par("cex"),
col = "darkgray",
lwd = par("lwd"),
lty = par("lty")
)

## Arguments

nlevels suggested number of density levels (i.e. isopycnal curves); ignored if levels is supplied. optional density levels to draw. boolean, set to TRUE to write all density labels horizontally. boolean, set to TRUE to write isopycnal labels as e.g. 1024 instead of 24. number of decimal digits to use in label (supplied to round()). equation of state to be used, either "unesco" or "gsw". size for labels. color for lines and labels. line width for isopycnal curves line type for isopycnal curves

## Value

None.

plotTS(), which calls this.