[R] lattice barchart with "negative" bars

[Luis Torgo]

Dear all,

I'm trying to use the lattice barchart function to obtain a bar plot of a 
variable for different values of two factors. The thing I'm trying to do is 
something like this:

> barchart(MyVar ~ season | place, data=mydataset)

My problem is that the column MyVar has some negative values and I would like 
them to be represented as bars stacking down from zero instead of what the 
function does that is finding the minimum value and then stacking all bars 
from this minimum value up. I've looked into the the help pages and I saw no 
way to go around this behaviour. Is there an easy way to get these "negative" 
bars?

Thanks,
Luis
 
-- 
Luis Torgo
    FEP/LIACC, University of Porto   Phone : (+351) 22 607 88 30
    Machine Learning Group           Fax   : (+351) 22 600 36 54
    R. Campo Alegre, 823             email : ltorgo at liacc.up.pt
    4150 PORTO   -  PORTUGAL         WWW   : http://www.liacc.up.pt/~ltorgo