[R] Post Hoc Groupings

[Jarrett Byrnes]

Quick question, as I attempt to learn R.  For post-hoc tests

1) Is there an easy function that will take, say the results of 
tukeyHSD and create a grouping table.  e.g., if I have treatments 1, 2, 
and 3, with 1 and 2 being statistically the same and 3 being different 
from both

Group	Treatment
A		1
A		2
B		3

2) I've been stumbling over the proper syntax for simple effects for a 
tukeyHSD test.  Is it

TukeyHSD(model.aov, "Treatment1", "Treatment2")
or
TukeyHSD(model, c("Treatment1", "Treatment2"))

or something else, as neither of those seem to really work.