> A[with(A, paste(C1, C2, sep = "\r")) %in% with(B, paste(C1, C2, sep="\r")), ] C1 C2 19 A 200
(Using sep = "\r" is perhaps a little too cautious.) Bill Venables http://www.cmis.csiro.au/bill.venables/ -----Original Message----- From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On Behalf Of Raghavan, Nandini [PRDUS] Sent: Thursday, 7 May 2009 4:19 PM To: r-help@r-project.org Subject: [R] Matching multiple columns in a data frame Hello, I am trying to extract a subset of a dataframe A (2 columns) by extracting all entries in A (several repeated entries) that match dataframe B in both columns. For example, part of A and B are shown below. The following does not seem to work correctly. This only seems to select on the first component and all instances of the second. ind <- A$C1 %in% B[,1] & A$C2 %in% B[,2] Any suggestions as to how to do this in general (even for matches in multiple columns) would be appreciated. Regards, Nandini A: C1 C2 1 F 1500 2 P 120 4 F 250 5 I 200 6 D 2010 7 F 1000 8 V 0 9 F 2100 10 F 500 11 E 1800 12 A 500 13 V 0 14 I 125 15 I 30 16 M 300 17 D 75 18 V 500 19 A 200 20 M 1000 21 P 225 B: C1 C2 1 A 200 2 A 600 3 A 1500 4 B 100 5 B 1000 6 C 5000 7 C 225 8 C 150 9 C 150 10 C 200 [[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. ______________________________________________ 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.
