oce (version 0.9-18)

mapContour: Plot contours on a existing map

Description

Plot contours on an existing map

Usage

mapContour(longitude=seq(0, 1, length.out=nrow(z)),
latitude=seq(0, 1, length.out=ncol(z)),
z,
nlevels=10, levels=pretty(range(z, na.rm=TRUE), nlevels), 
col=par("fg"), lty=par("lty"), lwd=par("lwd"))

Arguments

longitude

longitudes of points to be plotted, or an object of class topo (see topo-class), in which case longitude, latitude and z are inferred f

latitude

latitudes of points to be plotted

z

matrix to be contoured

nlevels

number of contour levels, if and only if levels is not supplied

levels

list of contour levels

col

colour of lines

lty

type of lines

lwd

width of lines

Bugs

As with mapLines, long lines should be subdivided into multiple segments so that e.g. great circle lines will be curved.

Details

Adds contour lines to an existing map, using mapLines. The arguments are based on those to contour and contourLines.

See Also

See mapPlot for general information on plotting maps, including other functions.

Examples

library(oce)
data(coastlineWorld)
par(mar=rep(1, 4))
## Arctic 100m, 2km, 3km isobaths, showing shelves and ridges.
mapPlot(coastlineWorld,
        latitudelim=c(60,120), longitudelim=c(-130,-50), 
        proj="stereographic", orientation=c(90, -90, 0), 
axes=FALSE, fill='lightgray')
data(topoWorld)
lon <- topoWorld[['longitude']]
lat <- topoWorld[['latitude']]
z <- topoWorld[['z']] 
mapContour(lon, lat, z, levels=c(-100, -2000, -3000),col=1:3,lwd=2)