Time to do some homework, Elaine: ?regexp
There are also numerous online tutorials on regular expressions that you can use to educate yourself. Cheers, Bert On Wed, Jul 31, 2013 at 2:07 PM, Elaine Kuo <elaine.kuo...@gmail.com> wrote: > Dear Arun > > Thank you for the very useful help. > However, please kindly explain the code below. > row.names(mat1)<- gsub("[_]"," ",row.names(mat1)) > > 1. what does "[_]" mean? > 2. what does " " mean? > 3. what does row.names(mat1) mean? > > I checked ?gsub but still did not get the idea. > > Thank you again > > Elaine > > > On Wed, Jul 31, 2013 at 9:35 PM, arun <smartpink...@yahoo.com> wrote: > >> HI, >> >> Please use ?dput() >> mat1<- as.matrix(read.table(text=" >> D0989 D9820 D5629 D4327 D2134 >> GID_1 1 0 0 1 0 >> GID_2 0 1 1 0 0 >> GID_4 0 0 1 0 0 >> GID_5 1 1 0 0 0 >> GID_7 0 1 0 0 1 >> ",sep="",header=TRUE)) >> row.names(mat1)<- gsub("[_]"," ",row.names(mat1)) >> IslandA<-c("GID 1", "GID 5") >> IslandB<- c("GID 2", "GID 4", "GID 7") >> res<- t(sapply(c("IslandA","IslandB"),function(x) >> {x1<-mat1[match(get(x),row.names(mat1)),];(!!colSums(x1))*1} )) >> >> res >> # D0989 D9820 D5629 D4327 D2134 >> #IslandA 1 1 0 1 0 >> #IslandB 0 1 1 0 1 >> A.K. >> >> >> >> >> ----- Original Message ----- >> From: Elaine Kuo <elaine.kuo...@gmail.com> >> To: "r-h...@stat.math.ethz.ch" <r-h...@stat.math.ethz.ch> >> Cc: >> Sent: Wednesday, July 31, 2013 9:03 AM >> Subject: [R] merge matrix row data >> >> Dear list, >> >> >> >> I have a matrix showing the species presence-absence on a map. >> >> Its rows are map locations, represented by GridCellID, such as GID1 and GID >> 5. >> >> Its columns are species ID, such as D0989, D9820, and D5629. >> >> The matrix is as followed. >> >> >> >> Now I want to merge the GridCellID according to the map location of each >> island. >> >> For instance, Island A consist of GID 1 and 5. Island B consist of GID 2, >> 4, and 7. >> >> In GID 1 and 5, species D0989 are both 1. >> >> Then I want to merge GID 1 and 5 into Island A, with species D0989 as 1. >> >> The original matrix and the resulting matrix are listed below. >> >> Please kindly advise how to code the calculation in R. >> >> Please do not hesitate to ask if anything is unclear. >> >> Thank you in advance. >> >> >> >> Elaine >> >> >> >> Original matrix >> >> D0989 D9820 D5629 D4327 D2134 >> >> GID 1 1 0 0 1 0 >> >> GID 2 0 1 1 0 0 >> >> GID 4 0 0 1 0 0 >> >> GID 5 1 1 0 0 0 >> >> GID 7 0 1 0 0 1 >> >> >> >> Resulting matrix >> >> D0989 D9820 D5629 D4327 D2134 >> >> Island A 1 1 0 1 0 >> >> Island B 0 1 1 0 1 >> >> [[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. >> >> > > [[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. -- Bert Gunter Genentech Nonclinical Biostatistics Internal Contact Info: Phone: 467-7374 Website: http://pharmadevelopment.roche.com/index/pdb/pdb-functional-groups/pdb-biostatistics/pdb-ncb-home.htm ______________________________________________ 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.