If you want to suppress the unused level of Species, you can use factor() :
table(base$Species) table(factor(base$Species)) 2008/8/28 glaporta <[EMAIL PROTECTED]> > > Hi, > sqldf is a fantastic package, but when the SELECT procedure runs unused > levels remain in the output. I tried with the drop function, but without > success. Do you have any suggestions? > Thanx, Gianandrea > > data(iris) > require(sqldf) > base<-sqldf("select * from iris where Species <> 'setosa'") > str(base) # Species with 3 levels! > > -- > View this message in context: > http://www.nabble.com/drop-unused-levels-in-sqldf-tp19196464p19196464.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.