Hi I want to do something like a <- c(10,20,15,43,76,41,25,46) tab <- data.frame(a) name <- "a" for (v in unique(tab[[name]])) { r <- subset(tab, name==v) # this does not work ... } i.e. a "string" on the left side of the select expression (subset). How could I solve this? thx Christof