Add a grid of meridians and latitude lines.

This function adds a grid of lat/lon lines to an existing plot.

Usage

DrawLatLon(nx=9, ny=9, lines = TRUE, labels = TRUE, lab.size = 1, 
           col = "grey", lty = 2, font = 2, lab.x = 2, lab.y = 2, 
           npoints = 500, ...)

Arguments

nx,ny

The (approximate) number of lines to be drawn.

lines, labels

If labels=TRUE, the latitude and longitude values are printed at the bottom and left of the map. If lines=TRUE, a grid of lines is drawn on the plot. If both are FALSE nothing happens, so what's the point...

col, lty, lab.size, font, lab.x, lab.y

Graphical parameters.

npoints

The number of points used to draw every meridian and latitude line. If the lines are very curved and plot is at high resolution, increasing this will give smoother lines.

...

More graphical parameters.

Value

Lines of constant latitude and longitude are added to the current map. The lines are at regular intervals with appropriate values to get aproximately the wanted number of lines.

See also

DomainPoints