[R] Boxplot in order

[Silvano]

Hi,

I need construct box plot graph, but I want keep Groups 
order

karla = data.frame(
Groups = 
factor(rep(c('CPre','SPre','C7','S7','C14','S14','C21','S21'), 
11)),
Time = rep(c(0,7,14,21), 11),
Resp = valor
)

boxplot(Resp~Groups, order=T)

doesn't work.

How do this?

--------------------------------------
Silvano Cesar da Costa
Departamento de Estatística
Universidade Estadual de Londrina
Fone: 3371-4346