[R] strip names lattice graphics

[GOUACHE David]

R-helpers,
 
I'm having difficulty with customizing strip names for a lattice graphic.
 
Here is an example using the iris data set :
 
xyplot(Sepal.Length+Sepal.Width~Petal.Length,groups=Species,data=iris)
 
## I'd like to change the 2 strip names to "Length" and "Width" for example, this is what I've tried :
 
xyplot(Sepal.Length+Sepal.Width~Petal.Length,groups=Species,data=iris,strip=strip.custom(strip.names=c(T,F),strip.levels=c(F,T),var.name=c("Length","Width")))
 
but I get "Length" in both strips, which is obviously not my goal...
Any pointers would be much appreciated as to how to achieve the desired result.
 
Many thanks !
 
> David Gouache

> ARVALIS - Institut du végétal

> Station de La Minière

> 78280 Guyancourt

> Tel: 01.30.12.96.22 / Port: 06.86.08.94.32