[R] Boxplots from lme objects

[CG Pettersson]

Dear all!

W_XP, R 2.6.0

I am evaluating variety trails over several years, where the different
cultivars have not been present in the dataset the same number of years.

I use lme{nlme} to fit random effect models and estimable{gmodels} to
extract the fixed effects. The general model is:

lme(y ~ cultivar, data = data, na.action=na.omit,
    random = ~ 1 | year/trial/rep)

The dataset is from six years and I only run the analyse on a subset
dataframe consisting the cultivars grown the last year (25 out of 82 for
the moment). All this runs well to produce tables, but what about
graphics?

How do I make boxplots from the lme objects? Producing the boxplots, I
want only 6 or 7 cultivars out of the 25 available in the object - so I
also need a way to subset the information in the lme objects.

Thank you

/CG




-- 
CG Pettersson, Ph.D.
Swedish University of Agricultural Sciences (SLU)
Dept. of Crop Production Ecology. Box 7043.
SE-750 07 Uppsala, Sweden
cg.pettersson at vpe.slu.se