Try this: evaluation$maxVol <- ave(evaluation$vol, evaluation$name, FUN = max)
or using SQL via sqldf like this: library(sqldf) sqldf("select * from evaluation join (select name, max(vol) from evaluation group by name) using (name)") On 8/31/07, Calle <[EMAIL PROTECTED]> wrote: > Hello, > > struggling with the very basic needs... :( any help appreciated. > > #using the package doBY > #who drinks how much beer per day and therefor cannot calculate rowise > maxvals > evaluation=data.frame(date=c(1,2,3,4,5,6,7,8,9), > name=c("Michael","Steve","Bob", > "Michael","Steve","Bob","Michael","Steve","Bob"), vol=c(3,5,4,2,4,5,7,6,7)) > evaluation # > > maxval=summaryBy(vol ~ name,data=evaluation,FUN = function(x) { c(ma=max(x)) > } ) > maxval # over all days per person > > #function > getMaxVal=function(x) { maxval$vol.ma[maxval$name==x] } > getMaxVal("Steve") # testing the function for one name is ok > > #we want to add a column, that shows the daily drinkingvolume in relation to > the persons max-vol. > evaluation[,"relDrink"]= evaluation$vol/getMaxVal(evaluation$name) > # > # this brings the error: > # > #Warning message: > # Korrupter Data Frame: Spalten werden abgeschnitten oder mit NAs > # aufgefüllt in: format.data.frame(x, digits = digits, na.encode = FALSE) > > errortest= evaluation$vol/getMaxVal(evaluation$name) > errortest > # this brings: > # numeric(0) > > > #target was the following: > #show in each line the daily consumed beer per person and in the next column > > #the all time max consumed beer for this person´(or divided by daily vol): > # > # date name vol relDrink > #1 1 Michael 3 7 > #2 2 Steve 5 6 > #3 3 Bob 4 7 > #4 4 Michael 2 7 > #5 5 Steve 4 7 > #6 6 Bob 5 7 > #7 7 Michael 7 7 > #8 8 Steve 6 6 > #9 9 Bob 7 7 > > # who can help??? > > [[alternative HTML version deleted]] > > > ______________________________________________ > R-help@stat.math.ethz.ch 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@stat.math.ethz.ch 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.