[R] Subset: data frames and factor levels

[Agustin Lobo]

Thanks, problem solved thanks to your hints, but, within subset(), 
drop=T still keeps
the unused levels (I'm using 2.6.1 on win).
Agus

Stefan Grosse escribió:
> On Tuesday 01 April 2008 09:43:00 am Agustin Lobo wrote:
> AL> I'm doing:
> AL> etni <- subset(etni, NAMECOM!="Maniquisito")
> AL>
> AL> where etni is a data.frame, NAMECOM a factor and "Maniquisito" labels
> AL> a row that I want to delete.
> AL>
> AL> The problem is that while the row is deleted, the factor level is still
> AL> there (I can see "Maniquisito" if I do levels(etni$NAMECOM) ).
> 
> See
> http://wiki.r-project.org/rwiki/doku.php?id=tips:data-manip:drop_unused_levels
> 
> Stefan
> 
> 
> 

-- 
Dr. Agustin Lobo
Institut de Ciencies de la Terra "Jaume Almera" (CSIC)
LLuis Sole Sabaris s/n
08028 Barcelona
Spain
Tel. 34 934095410
Fax. 34 934110012
email: Agustin.Lobo at ija.csic.es
http://www.ija.csic.es/gt/obster