Thanks a lot, David. Indeed, it's much shorter. Unfortunately, in my real task I am dozens and dozens of variables like var1 and var2 so that manually specifying things like in "m1=weighted.mean(var1,myweight)" would take a lot of code and a very long time. Dimitri
On Tue, Jul 17, 2012 at 6:34 PM, David Freedman <d...@cdc.gov> wrote: > The plyr package is very helpful for this: > > library(plyr) > ddply(x ,.(myweek), summarize, m1=weighted.mean(var1,myweight), > m2=weighted.mean(var2,myweight)) > > > -- > View this message in context: > http://r.789695.n4.nabble.com/weighted-mean-by-week-tp4636814p4636816.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. -- Dimitri Liakhovitski marketfusionanalytics.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.
