try sqldf: > x Sample_no Species Nitrogen Carbon 1 1 Cod 15.2 -19.0 2 2 Haddock 14.8 -20.2 3 3 Cod 15.6 -18.5 4 4 Cod 13.2 -20.1 5 5 Haddock 14.3 -18.8 > require(sqldf) > sqldf("select Species, avg(Nitrogen) Nitrogen, avg(Carbon) Carbon from x > group by Species") Species Nitrogen Carbon 1 Cod 14.66667 -19.2 2 Haddock 14.55000 -19.5
On Thu, Nov 4, 2010 at 8:28 AM, Ramsvatn Silje <silje.ramsv...@uit.no> wrote: > > Hello, > > I have tried to find this out some other way, but unsuccessful I have to > try this list. > I assume this should be quite simple. > > I have a dataset with 4 columns, "Sample_no", "Species", "Nitrogen", > "Carbon" in csv format. In the species column I have many different > species with varying number of obs per species > > Eg > > "Sample_no" "Species" "Nitrogen" "Carbon" > 1 Cod 15.2 -19.0 > 2 Haddock 14.8 -20.2 > 3 Cod 15.6 -18.5 > 4 Cod 13.2 -20.1 > 5 Haddock 14.3 -18.8 > Etc.. > > And I want to calculate, mean, standard dev etc per species for the > observations "Nitrogen" and "Carbon". And later do plots and stats with > the different species. I will in the end have many species, so need it to > be "automatic" I can't enter code for every species separate. > > Can anyone help me with this? Or if this is the wrong list to sendt this > question to, where do I send it? > > Thank you very much in advance. > > > Best regards > > Silje Ramsvatn > > PhD-candidate > University of Tromsø > Norway > > ______________________________________________ > 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. > -- Jim Holtman Cincinnati, OH +1 513 646 9390 What is the problem that you are trying to solve? ______________________________________________ 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.