Come to think of it the plyr package and the data.table packages also offer similar tools. For large merges (joins) I think the data.table package is much faster.
John Kane Kingston ON Canada > -----Original Message----- > From: steven.ran...@gmail.com > Sent: Tue, 27 Nov 2012 15:28:57 -0700 > To: jrkrid...@inbox.com > Subject: Re: [R] Finding values in one column and > > Thanks. > > Soon after I posted this question, I discovered merge(). > > Steven H. Ranney > > > On Tue, Nov 27, 2012 at 3:26 PM, John Kane <jrkrid...@inbox.com> wrote: >> Have a look at ?merge >> >> John Kane >> Kingston ON Canada >> >> >>> -----Original Message----- >>> From: steven.ran...@gmail.com >>> Sent: Tue, 27 Nov 2012 15:17:58 -0700 >>> To: r-help@r-project.org >>> Subject: [R] Finding values in one column and >>> >>> All - >>> >>> I have a data frame >>> >>> data.a >>> ID valueA valueB >>> 6 12 12 >>> 17 15 14 >>> 58 18 16 >>> 98 11 12 >>> 73 19 20 >>> 84 19 14 >>> 58 20 14 >>> 24 11 12 >>> 81 15 16 >>> 21 15 14 >>> 62 14 12 >>> 67 13 14 >>> 78 13 17 >>> 35 10 13 >>> 13 11 15 >>> 14 17 18 >>> 85 16 15 >>> 35 13 9 >>> 18 15 16 >>> >>> and a data frame >>> >>> data.b >>> ID valueA valueB >>> 6 >>> 84 >>> 21 >>> 78 >>> 14 >>> >>> I'd like to have R find the data.b$ID in data.a$ID and insert the >>> corresponding data.a$valueA and data.a$valueB into the appropriate >>> columns in data.b. >>> >>> How can I do this? >>> >>> Thanks for you help. >>> >>> SR >>> Steven H. Ranney >>> >>> ______________________________________________ >>> 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. >> >> ____________________________________________________________ >> Publish your photos in seconds for FREE >> TRY IM TOOLPACK at http://www.imtoolpack.com/default.aspx?rc=if4 >> >> ____________________________________________________________ FREE 3D MARINE AQUARIUM SCREENSAVER - Watch dolphins, sharks & orcas on your desktop! ______________________________________________ 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.
