Hi, Look to the following code:
set.seed(1) dados = data.frame(valor=rnorm(100),var=sample(LETTERS[c(1,2,3,5)],100,replace=T),peso=rpois(100,2)) dados[1:10,] dados$var <- factor(dados$var,levels=LETTERS[1:5]) table(dados$var) A B C D E 31 31 19 0 19 When I try to use summarize, Hmisc package it shows me the result without D category. g1 <- function(y) wtd.mean(y[,1],y[,2]) summarize(dados[,c(1,3)], llist(var=dados$var), g1,stat.name = 'med') var med 1 A 0.02589377 2 B 0.37123239 3 C -0.57820359 4 E 0.39584514 How do I get med = NA or something else with summarize? I realy need to the function to return all factors in the var even it they are an empty set. thanks in advance. leandro [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.