Use NROW rather than nrow. On Wed, Mar 17, 2010 at 11:23 AM, Tony Laidig <c...@mit.edu> wrote: > Hello Everyone- > I'm calculating summary statistics on a dataset (~4000 records, > observations are not uniformly distributed) using summaryBy and trying > to add a column with the number of observations to the output as well. > What occurs to me is to use nrow(), but this doesn't appear to be working > > I'm able to replicate the same results with an example from the > summaryBy docs: > > data(dietox) > dietox12<- subset(dietox,Time==12) > library(doBy) > #this one works > summaryBy(Weight+Feed~Evit+Cu,data=dietox12,FUN=c(mean,var,length)) > #adding nrow doesn't give the number of rows > summaryBy(Weight+Feed~Evit+Cu,data=dietox12,FUN=c(mean,var,length,nrow)) > > > There must be a way to do this, but I can't figure it out. I suspect > there is another function that would be compatible with summaryBy. > > Thanks in advance. > -Tony > > > > > [[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. >
______________________________________________ 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.