Hi, Here are some examples using the mtcars dataset that you can modify to work with your data.
## Here is my first try using within. ## Somehow the elements of region that ## should be zero are converted to NA mtcars <- within(mtcars, { region <- 0 region[gear==4&carb==4] <- 1 region[gear==3&carb==1] <- 2 }) ## Here is a second try with an ugly ## hack to fix the NA problem mtcars <- within(mtcars, { region <- NA region[gear==4&carb==4] <- 1 region[gear==3&carb==1] <- 2 region[is.na(region)] <- 0 }) ## Here is an alternative using with ## instead of within mtcars$region <- 0 mtcars$region[with(mtcars, gear==4&carb==4)] <- 1 mtcars$region[with(mtcars, gear==3&carb==1)] <- 2 Best, Ista On Wed, Jun 12, 2013 at 4:36 PM, bcrombie <bcrom...@utk.edu> wrote: > I'm adding a column (region) to a data frame (devUni8), and the (region) > column will be populated by a numeric code that is a function of another > column (state) in that data frame. See part of the script below. > > How can I rewrite this so that I could apply the conditions to any data > frame without having to keep typing its name (in this case, "devUni8$"). > I've heard the attach() function is to be avoided, and I'm not good at > with, > while, or if statements right now. I've tried some other things but keep > getting "object not found" errors. Assistance appreciated. Thanks. > > #Create Region Variable > ######### > devUni8$region=0 > > #Assign Northeast States > ######### > devUni8$region[devUni8$state >= 11 & devUni8$state <= 23 | devUni8$state >= > 51 & devUni8$state <= 55] = 1 > > #Assign Southeast States > ######### > devUni8$region[devUni8$state >= 56 & devUni8$state <= 64 ] = 2 > > > > -- > View this message in context: > http://r.789695.n4.nabble.com/rewrite-script-to-eliminate-constant-object-reference-tp4669393.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. > [[alternative HTML version deleted]] ______________________________________________ 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.