[R] what does "size" of a plotting character mean?

[Prasenjit Kapat]

Hi,

Thank you Prof Ripley for the response.

On 10/4/07, Prof Brian Ripley <ripley at stats.ox.ac.uk> wrote:
> On Thu, 4 Oct 2007, Prasenjit Kapat wrote:
>
> > Hi,
> >
> > plot(1,1, cex=2) means that the size of the plotting character (empty
> > circle in this case) is double the default size. Now my question is:
> >
> > What characteristic of the symbol (circle) is double? Is it the area
> > or the diameter?
>
> Is it not obvious when you try it?  Diameter.
>
> > What if the symbol is not a circle, what is the generic meaning of
> > size in that case?
>
> cex does linear scaling in each dimension.

I was hoping this would be true.

>
> There is no generic definition of what cex=1 means: it depends on the
> device, the font (for pch >=32 except ".") or the symbols (pch=1...25).


Thanks
PK