On Wed, 24 Dec 2003, Frederico Zanqueta Poleto wrote:
> Dear All,
>
> I have a fit from multinom (nnet library).
>
> When I try the command model.matrix(fit) in S-Plus 2000 or in R 1.7.1,
> everything is ok. But in S-Plus 6.1 I receive:
> Problem in formula$terms: function "$" not defined for non-vector class
> "multinom"
> Use traceback() to see the call stack
>
> Anybody know what is happening?
Yes. There is no model.matrix method for the S4 class "multinom" (just
as the error message says). multinom is not an S4 class in the S3-based
systems you quote, but in fact `everything is not OK' and this would only
work for some sets of arguments.
What do you actaully want to do?
--
Brian D. Ripley, ripley@stats.ox.ac.uk
Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/
University of Oxford, Tel: +44 1865 272861 (self)
1 South Parks Road, +44 1865 272866 (PA)
Oxford OX1 3TG, UK Fax: +44 1865 272595
|