Or

dd[,myname]

should work too.

If you are worried about getting multiple columns, you can just make myname a vector of column names using c() before you use either Jim's list indexing or the above matrix indexing syntax.
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Sent from my phone. Please excuse my brevity.

Jim Holtman <jholtman@gmail.com> wrote:

dd[[ myname]] Sent from my iPad On May 21, 2011, at 7:37, Lars Bishop <lars52r@gmail.com> wrote: > Let's say I have the data frame 'dd' below. I'd like to select one > column from this data frame (say 'a') and keep its name in the > resulting data frame. That can be done as in #2. However, what if I > want to make my selection based on a vector of names (and again keep > those names in the resulting data frame). My attempt is #4 but doesn't > work. > > dd <- data.frame(a = gl(3,4), b = gl(4,1,12), c=rnorm(12)) #1 > data.frame("a" = dd[,"a"]) #2 > > mynames <- "a" #3 > data.frame(eval(mynames) = dd[, mynames]) #4 > > thanks, > Lars. > >_____________________________________________
> 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. 


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