>From what you've provided its nearly impossible to help you. I think that I understand enough to provide a solution the problem that I believe you are posing.
First some comments: (1) You can't expect that passing a character string to the argument of tapply that expects a function to work (2) Note that the INDEX argument of tapply must be of class 'factor' (3) From what you've provided it isn't clear where 'ttime' and 'fmt' are coming from, or even that they are of the same length as dfd[,param[1]] which is neccesary in order for this to work, but I will assume that you have a handle on that. Since they first appear within the definition of function 'dd', then you should most likely include them as arguments to 'dd' unless you want to gamble on them being defined either in the global frame or the frames ancestral to the frame of evaluation. (4) I'm willing to bet that you've been using the '...' un-named arguments to 'dd' in hopes that this would be a kind of magic bandaid..., and I'm willing to bet that you really don't need it. param.to.pass<-c(1,'max','h') dd<- function(dfd, param=param.to.pass, ttime, fmt){ ttime.int <- format(ttime,fmt) ttime.fact <- as.factor(ttime.int) data.frame( param[3] = tapply(dfd[,param[1]],ttime.fact, FUN=function(x, fn.nm=param[3]){ .call. <- match.call() .call.[[1]] <- as.name(fn.nm) })) } -----Original Message----- From: Yuri Volchik [mailto:[EMAIL PROTECTED] Sent: Fri 3/7/2008 6:06 AM To: r-help@r-project.org Subject: [R] Passing function to tapply as a string Hi, Was wondering if it is possible to pass function name as a parameter, smth along this line param.to.pass<-c(1,'max','h') dd<-function(dfd, param=param.to.pass,...){ ttime.int <- format(ttime,fmt) data.frame( param[3] = tapply(dfd[,param[1]],ttime.int,param[3]), ...) } I know there is a as.formula expression but not quite sure if there is some way to accomplish what i need. Thanks -- View this message in context: http://www.nabble.com/Passing-function-to-tapply-as-a-string-tp15891151p15891151.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.