Hi Marine, I'm not sure that I have the right idea, but this worked for me and may help.
# I had to fix this line df<-data.frame(id=rep(1:10,each=10),item1=sample(1:20, 100, replace=TRUE)) df2<-data.frame(a=c(8, 8,10,9, 5, 1,2,1),b=c(16,18,11, 19,18, 11,17,12)) result<-data.frame(id=df[,1],rown=1:dim(df)[1],matched=rep(FALSE,dim(dfw)[1])) # function that checks that all entries in vector a exist in vector x match_all_a<-function(a,x,index) { inx<-TRUE for(i in 1:length(a)) inx <- inx && a[i] %in% x[-1] return(list(id=x[1],rown=index,matched=inx)) } # step through the data frame for(i in df[,1]) result[i,]<-match_all_a(df2[i,],df[i,],i) # display the result id, row in df, whether matched result # select the rows of result for which matched is TRUE Jim On Fri, Oct 7, 2022 at 11:57 PM Marine Andersson <marine.anders...@ki.se> wrote: > > Hi, > > If I have two datasets like this: > df=data.frame("id"=rep(1:10,10, each=10), "item1"=sample(1:20, 100, replace=T) > df2=data.frame("a"=c(8, 8,10,9, 5, 1,2,1), "b"=c(16,18,11, 19,18, 11,17,12)) > > How do I find out which ids in the df dataset that has a match for both the > numbers occuring in the same row in the df2 dataframe? In the output I would > like to get the matching id and the rownumber from the df2. > > Output something like this > Id Rownr > 2 1 > 5 1 > 7 4 > > My actual problem is more complex with even more columns to be matched and > the datasets are large, hence the solution needs to be efficient. > > Kind regards, > > > > > > N?r du skickar e-post till Karolinska Institutet (KI) inneb?r detta att KI > kommer att behandla dina personuppgifter. H?r finns information om hur KI > behandlar personuppgifter<https://ki.se/medarbetare/integritetsskyddspolicy>. > > > Sending email to Karolinska Institutet (KI) will result in KI processing your > personal data. You can read more about KI's processing of personal data > here<https://ki.se/en/staff/data-protection-policy>. > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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 -- To UNSUBSCRIBE and more, see 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.