Full_Name: Hilmar Berger Version: 2.4.1/2.6.2alpha OS: WinXP Submission from: (NULL) (84.185.128.110)
Hi all, If I use tapply on an empty data.frame I get an error. I'm not quite sure if one can actually expect the function to return with a result. However, the error message suggests that this case does not get handled well. This happens both in R-2.4.1 and 2.6.2alpha (version 2008-01-26). > z = data.frame(a = c(1,2,3,4),b=c("a","b","c","d")) > z1 = subset(z,a == 5) > tapply(z1$a,z1$b,length) Error in ansmat[index] <- ans : incompatible types (from NULL to logical) in subassignment type fix Deleting unused factor levels from the group parameter gives: > tapply(z1$a,factor(z1$b),length) logical(0) Regards, Hilmar platform i386-pc-mingw32 arch i386 os mingw32 system i386, mingw32 status alpha major 2 minor 6.2 year 2008 month 01 day 26 svn rev 44181 language R version.string R version 2.6.2 alpha (2008-01-26 r44181) ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel