I have two data frames with a name column containing affy probeset ids. I would like to pull out the ids (just the ids) which are common in both data frames. (Actually, I could just have to character vectors and would like to print the common elements). I tried this approach: for (elx in x) {for (ely in y) {if (elx==ely) print(ely)}} x, y : character vectors This prints out the correct result but I am not able to assign the resulting probesets and it also seems quite an inelegant solution. Thank you for your help. Juerg Straubhaar UMass Med School

> > > I have two data frames with a name column containing affy > probeset ids. I would like to pull out the ids (just the ids) > which are common in both data frames. (Actually, I could just > have to character vectors and would like to print the common > elements). > > I tried this approach: > > for (elx in x) {for (ely in y) {if (elx==ely) print(ely)}} > > x, y : character vectors do intersect(x,y) or better type help(intersect) which gives you the help for set operations in R. regards, Arne > This prints out the correct result but I am not able to > assign the resulting probesets and it also seems quite an > inelegant solution. > > Thank you for your help. > > Juerg Straubhaar > UMass Med School > > _______________________________________________ > Bioconductor mailing list > Bioconductor@stat.math.ethz.ch > https://www.stat.math.ethz.ch/mailman/listinfo/bioconductor >

>I have two data frames with a name column containing affy probeset ids. I would like to pull out the ids (just the ids) which are common in both data frames. (Actually, I could just have to character vectors and would like to print the common elements). > >I tried this approach: > >for (elx in x) {for (ely in y) {if (elx==ely) print(ely)}} > >x, y : character vectors Would this work for you: > d1 <- data.frame(matrix(1:20, ncol = 4)) > d2 <- data.frame(matrix(3:22, ncol = 4)) > tt <- intersect(d1[,1], d2[,1]) > d1[d1[,1] %in% tt,] > >This prints out the correct result but I am not able to assign the resulting probesets and it also seems quite an inelegant solution. > >Thank you for your help. > >Juerg Straubhaar >UMass Med School > >_______________________________________________ >Bioconductor mailing list >Bioconductor@stat.math.ethz.ch >https://www.stat.math.ethz.ch/mailman/listinfo/bioconductor Jianhua Zhang Department of Biostatistics Dana-Farber Cancer Institute 44 Binney Street Boston, MA 02115-6084

See help(match). Note that match returns the _first_ match. AFAIK, the probeset ids are unique within any given cdf file, so this should not be a problem. On Tue, 2004-05-04 at 17:02, Straubhaar, Juerg wrote: > I have two data frames with a name column containing affy probeset ids. I would like to pull out the ids (just the ids) which are common in both data frames. (Actually, I could just have to character vectors and would like to print the common elements). > > I tried this approach: > > for (elx in x) {for (ely in y) {if (elx==ely) print(ely)}} > > x, y : character vectors > > This prints out the correct result but I am not able to assign the resulting probesets and it also seems quite an inelegant solution. > > Thank you for your help. > > Juerg Straubhaar > UMass Med School > > _______________________________________________ > Bioconductor mailing list > Bioconductor@stat.math.ethz.ch > https://www.stat.math.ethz.ch/mailman/listinfo/bioconductor --