[R] how to make the units in x and y axis equal?

[Prof Brian Ripley]

On Wed, 17 May 2006, Haiyong Xu wrote:

> Hi there,
> I encountered a problem when plotting circles. It looks weird that the radii 
> in x and y axis are different since the default lengths of units in x and y 
> axes are different.
> Is there any way to make the units equal?
> I run the following codes and got a plot attached.
>
> symbols(rep(0,6), rep(0,6), circles = c(5, 15, 25, 35, 45, 55), inches = 
> FALSE, xlim = c(-60,60), ylim = c(-60, 60))

Add asp=1 (see ?symbols).

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
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