oce (version 0.9-18)

mapScalebar: Draw a scalebar on an existing map

Description

Draw a scalebar on an existing map

Usage

mapScalebar(x, y=NULL, length,
            lwd=1.5*par("lwd"), cex=par("cex"), col="black")

Arguments

x, y

position of the scalebar. Eventually this should be similar to the corresponding arguments in legend, but at the moment y must be NULL and x must be

length

length to indicate, in kilometres. If not provided, a reasonable choice is made, based on the underlying map.

lwd

scalebar line width

col

scalebar colour

cex

scalebar character size

Details

The scale is appropriate to the centre of the plot, and will become increasingly inaccurate away from that spot, with the error depending on the projection and the fraction of the earth that is shown.

See Also

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

Examples

library(oce)
## Arctic Ocean
data(coastlineWorld)
latlim <- 90 + 25 * c(-1, 1)
lonlim <- c(-130, -50)
orientation <- c(90, -90, 0)
proj <- "stereographic"
fill <- "lightgray"
mapPlot(coastlineWorld, latitudelim=latlim, longitudelim=lonlim,
        proj=proj, orientation=orientation,
        axes=FALSE, fill=fill)
mapScalebar()