Thank you, character indexing (?"[") is what I was looking for: sapply(paste('var', 1:100, sep=''), function(x) weighted.mean(data[[x]], data$weight))
Daniel On Mon, Aug 27, 2012 at 6:26 PM, Bert Gunter <gunter.ber...@gene.com> wrote: > Have you read "An Introduction to R". If not, please do so before > osting and pay particular attention to the section on indexing. If so, > re-read the sections on indexing. > > For a terser exposition, ?"[" > > -- Bert > > On Mon, Aug 27, 2012 at 7:11 AM, Daniel Caro <dca...@gmail.com> wrote: >> Hello, >> >> This is a beginner question. I am trying to loop through numbered >> variables with "apply" to calculate weighted means. My data is "data", >> the variables are "var1" to "var100", the weight is "weight". The >> command works using >> >> sapply(paste('data$var', 1:100, sep=''), function(x) >> weighted.mean(eval(parse(text=x)), data$weight)) >> >> but is there a way to avoid eval(parse())? >> >> Thank you, >> Daniel >> >> ______________________________________________ >> 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. > > > > -- > > Bert Gunter > Genentech Nonclinical Biostatistics > > Internal Contact Info: > Phone: 467-7374 > Website: > http://pharmadevelopment.roche.com/index/pdb/pdb-functional-groups/pdb-biostatistics/pdb-ncb-home.htm ______________________________________________ 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.