Hi, Try this: A<-data.frame(FID=c("a","a","b","b","c","c","d","d","d","d")) B<-read.table(text=" FID Age a 5 b 7 c 9 d 3 ",sep="",header=TRUE) library(plyr) join(A,B,type="inner") Joining by: FID FID Age 1 a 5 2 a 5 3 b 7 4 b 7 5 c 9 6 c 9 7 d 3 8 d 3 9 d 3 10 d 3 A.K.
----- Original Message ----- From: Sapana Lohani <lohani.sap...@ymail.com> To: "r-help@r-project.org" <r-help@r-project.org> Cc: Sent: Sunday, August 19, 2012 8:56 PM Subject: [R] relating data in two data frames Hi, My data.frame "A" has FID like this FID a a b b b c c d d d d Now my second data.frame "B" has age value for a, b, c, d like FID Age a 5 b 7 c 9 d 3 How can search for the Age column in "B" and replace the values in "A" so that my new "A" looks like this FID Age a 5 a 5 b 7 b 7 b 7 c 9 c 9 d 3 d 3 d 3 d 3 Thanks you [[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.