On Mon, Mar 11, 2013 at 3:17 PM, Dan Abner <dan.abne...@gmail.com> wrote: > Hi everyone, > > I have the following call to the merge() function. How does one > prevent duplicate columns in the resulting data frame that the 2 > parent data frames have in common but are not true key or "by" > variables? > > > data3<-merge(data1,data2,by="id") > data3 > > id total.x total.y balance > 1 78 78 90 > 2 91 91 63 > 3 74 74 57 > 4 89 89 58 > 5 90 90 27 > > > In this example, total is not a true key or "by" variable that > uniquely identifies rows suitable for matching purposes, but instead > just happens to be common to both sets.
Well, which one do you want? Or do you want to exclude total from the result? > > In reality, I have hundreds for these "in common" variables, so I need > a solution that is tractable for a large number of "in common" > columns. > > Thanks! > > Dan > > ______________________________________________ > 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.