[R-sig-eco] Plotting ternary diagrams

[Gavin Simpson]

On Thu, 2008-06-19 at 11:56 -0400, Phil Novack-Gottshall wrote:
> Hi all,
> 
> Can anyone point me to a function for plotting a ternary diagram (a 
> triangular plot; typically, each axis ranges 0-100% with cumulative 
> value for each point adding to 100% along all three axes)?  It's 
> frequently used by geologists to plot sedimentological or 
> mineralogical composition, and I think I've seen it used in biome 
> mapping (temperature/elevation/moisture).

RSiteSearch("ternary", restrict = "functions")

And take a look at some of the hits from there.

HTH

G

> 
> A bit further afield, do any functions exist to extend this to 4 
> axes, as a pyramidal quarternary diagram?
> 
> Thanks for any advice,
> Phil
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