Here is an option: grp = c(1,1,1, 1,2, 2,2) val = c(2,1,5,NA,3,NA,1) dta = data.frame(grp=grp, val=val) ddply(dta,"grp",summarise,count=length(na.omit(val))) Felipe D. Carrillo Supervisory Fishery Biologist Department of the Interior US Fish & Wildlife Service California, USA
----- Original Message ---- > From: Marcus Drescher <dresc...@tum.de> > To: "r-help@r-project.org" <r-help@r-project.org> > Sent: Fri, October 8, 2010 8:04:40 AM > Subject: Re: [R] Count values in a dataframe with respect to groups > > Thanks! It works great. > > One more question: how would I have to set the formula if I would have the >columns to count (val1 and val2)? > > > Betreff: Re: [R] Count values in a dataframe with respect to groups > > Try this: > > aggregate(val ~ grp, dta, length) > > On Fri, Oct 8, 2010 at 11:28 AM, Marcus Drescher <dresc...@tum.de> wrote: > Dear all, > > I am looking for a function to count values belonging to a class within a >dataframe (and ignore NAs). > > grp = c(1,1,1, 1,2, 2,2) > val = c(2,1,5,NA,3,NA,1) > > dta = data.frame(grp=grp, val=val) > > The result should look like: > > grp count > 1 3 > 2 2 > > At the moment, I am trying to find a function for FUN in aggregate, but with > no >success. Can anybody help me? > > Thanks in advance. > Marcus > > ______________________________________________ > 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. > > > > -- > Henrique Dallazuanna > Curitiba-Paraná-Brasil > 25° 25' 40" S 49° 16' 22" O > > ______________________________________________ > 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.
