[R] Negative value on ternaryplot

[Poizot Emmanuel]

Dear all,
I found a wonderful package (vcd) able to plot ternary diagrams, i.e. 
ternaryplot (thanks D. Meyer).
The problem is that one of three variable has negative values.
If I use the ternaryplot function but some points are outside the 
triangle, as value en negative.
Is it possible to make the ternary diagram fit exactly the cloud points ?
Regards

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Emmanuel Poizot
Cnam/Intechmer
B.P. 324
50103 Cherbourg Cedex

Phone (Direct) : (00 33)(0)233887342
Fax : (00 33)(0)233887339
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