R help - Sep 2007 - covariates in nlmer function

I am trying to explore nlmer by running some nlme examples from Pinheiro
& Bates (2000). I do not seem to find information how to specify fixed
effects covariates to nlmer models. Specifically, I tried to run the
"Carbon Dioxide Uptake" example from p. 368 onwards in the PB200 book.
The model without fixed effects covariates runs well but how to tell
nlmer to include Type and Treatment similar to the nlme model on p. 374
in the PB2000 book? Or is this something that has not been implemented
yet?

regards,
Kari Ruohonen

On 9/14/07, Kari Ruohonen <kari.ruohonen at utu.fi>
wrote:
> I am trying to explore nlmer by running some nlme examples from Pinheiro
> & Bates (2000). I do not seem to find information how to specify fixed
> effects covariates to nlmer models. Specifically, I tried to run the
> "Carbon Dioxide Uptake" example from p. 368 onwards in the PB200
book.
> The model without fixed effects covariates runs well but how to tell
> nlmer to include Type and Treatment similar to the nlme model on p. 374
> in the PB2000 book? Or is this something that has not been implemented
> yet?
To tell you the truth, I'm not sure.

I have been preparing classes and attending so many oral exams
recently that I can't remember exactly what capabilities are available
in nlmer right now.  I'll reply more definitively next week when I get
a chance to catch my breath a bit.