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.