[R] Putting frame around single panels in ggplot 2 and facet_grid()

[Rainer M Krug]

Hi

I want to highlight two panels in a grid created with facet_grid() by 
putting a box around it or usiong another background colour. Is this 
possible, and if yes, how?

Thanks

Rainer

-- 
Rainer M. Krug, Dipl. Phys. (Germany), MSc Conservation
Biology (UCT)

Plant Conservation Unit
Department of Botany
University of Cape Town
Rondebosch 7701
South Africa

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