intersect(names(data1),names(data2)) --------------------------------------------------------------------------- Jeff Newmiller The ..... ..... Go Live... DCN:<jdnew...@dcn.davis.ca.us> Basics: ##.#. ##.#. Live Go... Live: OO#.. Dead: OO#.. Playing Research Engineer (Solar/Batteries O.O#. #.O#. with /Software/Embedded Controllers) .OO#. .OO#. rocks...1k --------------------------------------------------------------------------- Sent from my phone. Please excuse my brevity.
Dan Abner <dan.abne...@gmail.com> wrote: >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. ______________________________________________ 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.