I am not sure what you want, but: 1) If you have not already done so, go through an R tutorial or two. For some suggestions:
https://www.rstudio.com/resources/training/online-learning/#R R is quite different than SAS. 2) If I misunderstand, perhaps ?within is what you are looking for. Cheers, Bert Bert Gunter "The trouble with having an open mind is that people keep coming along and sticking things into it." -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip ) On Wed, Feb 3, 2016 at 10:23 AM, Amoy Yang via R-help <r-help@r-project.org> wrote: > population is the field-name in data-file (say, tab). MVAR<-population takes > data (in the column of population) rather than field-name as done in SAS: > %let MVAR=population; > In the following r-program, for instance, I cannot use ... tab$MVAR...or > simply MVAR itself since MVAR is defined as "population" with double quotes > if using MVAR<-c("population") > > On Wednesday, February 3, 2016 11:54 AM, Duncan Murdoch > <murdoch.dun...@gmail.com> wrote: > > > On 03/02/2016 12:41 PM, Amoy Yang via R-help wrote: >> There is a %LET statement in SAS: %let MVAR=population; Thus, MVAR can be >> used through entire program. >> In R, I tried MAVR<-c("population"). The problem is that MAVR comes with >> double quote "...." that I don't need. But MVAR<-c(population) did NOT work >> out. Any way that double quote can be removed as done in SAS when creating >> macro_var? >> Thanks in advance for helps! > > R doesn't have a macro language, and you usually don't need one. > > If you are only reading the value of population, then > > MAVR <- population > > is fine. This is sometimes the same as c(population), but in general > it's different: c() will remove some attributes, such as > the dimensions on arrays. > > If you need to modify it in your program, it's likely more complicated. > The normal way to go would be to put your code in a function, and have > it return the modified version. For example, > > population <- doModifications(population) > > where doModifications is a function with a definition like > > doModifications <- function(MAVR) { > # do all your calculations on MAVR > # then return it at the end using > MAVR > } > > Duncan Murdoch > > > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
