I knew I was missing the obvious. And to think it's only Monday... Thanks everyone!
baptiste 2009/9/21 Henrique Dallazuanna <www...@gmail.com>: > Try this: > > do.call(expand.grid, rep(list(0:1), 4)) > > On Mon, Sep 21, 2009 at 2:04 PM, baptiste auguie > <baptiste.aug...@googlemail.com> wrote: >> Dear list, >> >> I think I'm being dense, but I can't get combn or expand.grid to give >> me this result. I need to generate a matrix of all 16 possible >> sequences of 4 boolean elements, >> >> 0000 >> 0001 >> 0010 >> 0011 >> 0100 >> ..... >> 1111 >> >> (in the end I'll have to assign NA to the 0s and some value to the 1s >> but let's keep it simple) >> >> OK, I could go the following route, but I feel like reinventing the >> wheel (and poorly), >> >> >> binarize <- function(x){ >> xt <- x >> bin <- vector() >> while(xt !=0){ >> bin <- c(bin, xt %% 2) >> xt <- xt %/%2 >> } >> c(rep(0, 4 - length(bin)), bin) >> } >> >> sapply(0:15, binarize) >> >> [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10] [,11] [,12] >> [,13] [,14] [,15] [,16] >> [1,] 0 0 0 0 0 0 0 0 0 1 0 1 >> 0 1 0 1 >> [2,] 0 0 0 0 0 1 0 1 0 0 1 1 >> 0 0 1 1 >> [3,] 0 0 0 1 0 0 1 1 0 0 0 0 >> 1 1 1 1 >> [4,] 0 1 1 1 1 1 1 1 1 1 1 1 >> 1 1 1 1 >> >> >> Have I missed a better way? >> >> Thanks, >> >> baptiste >> >> ______________________________________________ >> 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. >> > > > > -- > Henrique Dallazuanna > Curitiba-Paraná-Brasil > 25° 25' 40" S 49° 16' 22" O > ______________________________________________ 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.