[R] Draw a circle with a given radius in an existing map

[Duncan Murdoch]

On 11/7/2006 12:11 AM, Xiaomei Ma wrote:
> I have drawn a map in which the X and Y axes are latitude and 
> longitude. Now I need to draw one circle on the map - the center is a 
> point with specific latitude and longitude, but the challenge is that 
> the radius is in miles. Is there a way to do this? I'd very much 
> appreciate your response.

You want the circle to appear to be a circle on the plot, or an accurate 
representation of a circle on the ground (which may not be circular when 
plotted)?

Uwe answered the former.  I don't know the answer to the latter, but 
surely someone does...

Duncan Murdoch