Thanks for the explainable, Denes. Your solution worked a charm. I should have seen things more clearly, but sometimes I just get stuck in a rut.
The help of this list is always appreciated -- such a fantastic resource. Cheers, Sarah 2011/7/28 "Dénes TÃTH" <tde...@cogpsyphy.hu> > > Sorry, I was wrong. Of course you can assign a variable to itself, but it > does not make much sense... > What you misunderstood was that in the assignment you assign the data > frame (e.g. "df1") to itself. You do not modify the frame object which > remains a character string. > > > > > > The problem is that you can not assign a variable to itself. > > > > rm(list=ls()) > > df1 <- data.frame(ResultValue=as.character(1:5)) > > df2 <- data.frame(ResultValue=as.character(1:10)) > > frames = ls() > > for (frame in frames){ > > temp <- get(frame) > > temp[,"ResultValue"] = as.numeric(temp[,"ResultValue"]) > > assign(frame,temp) > > } > > > > HTH, > > Denes > > > > > > > >> Greetings to all -- > >> > >> I am having a silly problem that I just can't solve. Someone has given > >> me > >> an .RData file will hundreds of data frames. Each data frame has a > >> column > >> named ResultValue, currently character when it should be numeric. I > >> want > >> to > >> loop through all of the data frames to change the variable to numeric, > >> but > >> I > >> cannot figure out how to do it. My best guess was along the lines of: > >> > >> frames = ls() > >> for (frame in frames){ > >> assign(frame, get(frame), .GlobalEnv) > >> frame[,"ResultValue"] = as.numeric(frame[,"ResultValue"]) > >> } > >> > >> It doesn't work. After the assign() the frame object remains the > >> character > >> name of the dataframe I am trying to change. If I do the following, the > >> TEST object comes out just fine. > >> > >> frames = ls() > >> for (frame in frames){ > >> assign("TEST", get(frame), .GlobalEnv) > >> TEST[,"ResultValue"] = as.numeric(TEST[,"ResultValue"]) > >> } > >> > >> Seems like it should be simple, but I am misunderstanding something and > >> not > >> following the logic. Any insight? > >> > >> Thanks, > >> > >> Sarah > >> > >> [[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. > >> > > > > ______________________________________________ > > 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.