Udo Seems you might want merge()
HTH ....... Peter Alspach > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Udo > Sent: Monday, 14 April 2008 6:41 a.m. > To: r-help@r-project.org > Subject: [R] Matched pairs with two data frames > > Hi, > I have a frame "treat" and want to find matched pairs in the > data frame "control". In the matched (combined) data frame > there should be two variables (0/1),indicating the "source" > of the data (treat or control), so that it is possibe to set > a "filter" (extraxt/select data). > > #Here are the dataframes (my real data frames have many > variables) treat <- data.frame(age=c(1,1,2,2,2,4), > school=c(10,10,20,20,20,11), > out1=c(9.5,2.3,3.3,4.1,5.9,4.6)) control > <- data.frame(age=c(1,1,1,1,3,2), > school=c(10,10,10,10,33,20), > out2=c(1.1,2,3.5,4.9,5.2,6.5)) > print(treat) > print(control) > > matched.data.frame <- ?????? #Match "treat" "control" by age school > > > #My SPSS syntax would be similar to this: > MATCH FILES FILE="treat" /IN=fromtreat > /FILE="control" /IN=fromcontrol > /BY age school. > SELECT IF fromdad AND fromfam. #select data, set filter > > The /IN= option creates a 0/1 variable that indicates the > "source" of the data > > The resultand matched data frame should have the following structure: > age school out1 out2 fromtreat fromcontrol > 1 10 9.5 1.1 1 1 > 1 10 2.3 2.0 1 1 > .... > 4 11 4.6 NA 1 0 > 3 33 NA 5.2 0 1 > .... > > I tried "which" and "match", but I failed and was unlucky > looking at the help/archive. Merge doesn´t do the job, > because it makes all possible matches. > > > Thank´s for any help! > Udo > > > -------------------------------------------- > Udo K N G > Ö I > > Clinic for Child an Adolescent Psychiatry Philipps University > of Marburg / Germany > > ______________________________________________ > 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. > The contents of this e-mail are privileged and/or confidential to the named recipient and are not to be used by any other person and/or organisation. If you have received this e-mail in error, please notify the sender and delete all material pertaining to this e-mail. ______________________________________________ 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.