If replace 1:5 to char2 = c('east','west','south','north','central'), how to put on column names with the original structure? Thanks again.
On Wed, Jul 27, 2016 at 12:40 PM, Hervé Pagès <hpa...@fredhutch.org> wrote: > Hi, > > > On 07/27/2016 11:17 AM, lily li wrote: > >> Hi all, >> >> I want to ask that how to create column names for a matrix. For example, >> the matrix below, the column names should be: 1-A, 1-B, 1-C, 1-D, 2-A, >> 2-B, >> 2-C, 2-D, 3-A, etc. Thanks for your help. >> >> chars = c('A','B','C','D') >> matrix1 = matrix(nrow = length(1:100), ncol = length(1:5)*length(chars)) >> k = 0 >> for(i in seq(1:length(1:5))){ >> for(j in seq(1:length(chars))){ >> k = k+1 >> matrix1[,k] = c(1:100)[k] >> } >> } >> > > Also how could you possibly use such level of code obfuscation to > perform such simple initialization of your matrix? > > My 1st advice would be that you slow down and take the time to compare > seq(1:length(1:5)) with 1:length(1:5) with 1:5. It will be a great > learning experience! > > As for initializing your matrix, what about doing > > ncol <- 5 * length(chars) > matrix1 <- matrix(seq_len(ncol), nrow=100, ncol=ncol, byrow=TRUE) > > instead? > > Then set the colnames with: > > colnames(matrix1) <- paste(rep(1:5, length(chars)), chars, sep="-") > > Cheers, > H. > > >> [[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. >> >> > -- > Hervé Pagès > > Program in Computational Biology > Division of Public Health Sciences > Fred Hutchinson Cancer Research Center > 1100 Fairview Ave. N, M1-B514 > P.O. Box 19024 > Seattle, WA 98109-1024 > > E-mail: hpa...@fredhutch.org > Phone: (206) 667-5791 > Fax: (206) 667-1319 > [[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.