Ok, let's say I only want the common columns from data1. Is there a succinct way of doing this for potentially hundreds of "in common" columns?
On Mon, Mar 11, 2013 at 3:25 PM, Ista Zahn <istaz...@gmail.com> wrote: > 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.
