Thanks!  Unfortunately, in my effort to simply the question, I didn't really
adequately describe the problem.  This solution is perfect in the numeric
case I presented, but what about in the case of character classes!  Let me
try again:

I have
>character.data
           id     x        y
       1   1    "a"    NA
       2   2    "b"     "b"
       3   3    "c"      "c"
       4   4   NA      "d"


And I want first
>new.character.data
           id     x        y        z
       1   1    "a"    NA      "a"
       2   2    "b"     "b"     "b"
       3   3    "c"      "c"    "c"
       4   4   NA      "d"     "d"

Thanks again!




On Thu, Feb 24, 2011 at 4:27 PM, Ista Zahn <izahn@psych.rochester.edu>wrote:

> I think the easiest way is probably
>
> data$z <- rowMeans(data[, c("x", "y")], na.rm=TRUE)
>
> Best,
> Ista
>
> On Fri, Feb 25, 2011 at 12:12 AM, Andrew Anglemyer
> <andrew.anglemyer@gmail.com> wrote:
> > I am trying to combine two columns in a data frame into one column.  Some
> > values in either column are missing, but not in the same row for the two
> > different columns.  Additionally, when both columns in a row contain
> data,
> > the data are identical.  I want a new column with the identical data or
> the
> > data from the column with observed data.  For example:
> >
> > I have
> >>data
> >           id   x    y
> >       1   a   1   NA
> >       2   b   2    2
> >       3   c   3    3
> >       4   d  NA  4
> >
> > And I want
> >>new.data
> >           id   x    y     z
> >       1   a   1   NA   1
> >       2   b   2    2     2
> >       3   c   3    3     3
> >       4   d  NA  4     4
> >
> > I've looked through the help and there are column combining solutions,
> but
> > they don't seem to work well for this solution.
> > Thanks for any help!
> > Andy
> >
> >        [[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.
> >
>
>
>
> --
> Ista Zahn
> Graduate student
> University of Rochester
> Department of Clinical and Social Psychology
> http://yourpsyche.org
>

	[[alternative HTML version deleted]]

