Honestly, I wasn't sure what you wanted to do with 'group'. Here it is with the 'group' variable deleted
library(data.table) dt=data.table(x[,-1]) dt[,lapply(.SD, function(x)weighted.mean(x,myweight)), keyby='myweek'] -- View this message in context: http://r.789695.n4.nabble.com/weighted-mean-by-week-tp4636814p4636828.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.
