Dear R-help list, I have a problem in which I would like to concatenate elements from lists in a combinational order. For example, I have a list of n character vectors (here 3), each with m elements (here 7,3,1):
lst <- list(c("a","aB","aBC","aC","B","BC","C"), c("B","Bc","c"), c("D")) [[1]] [1] "a" "aB" "aBC" "aC" "B" "BC" "C" [[2]] [1] "B" "Bc" "c" [[3]] [1] "D" As the first list element has seven, the second has three and the third has one element, there are 21 different combinations of the individual vector elements: idx <- expand.grid(1:7,1:3,1:1) Var1 Var2 Var3 1 1 1 1 2 2 1 1 . . . . 6 6 1 1 7 7 1 1 8 1 2 1 9 2 2 1 . . . . 20 6 3 1 21 7 3 1 How could I create an exhaustive list of length 21 now, each of whose elements contains a unique combination of vector elements? I.e., the final list should look like this [[1]] [1] "a" "B" "D" [[2]] [1] "aB" "B" "D" [[3]] [1] "aBC" "B" "D" [[4]] [1] "aC" "B" "D" ..... [[21]] [1] "C" "c" "D" Many thanks for help, Alrik ******************************** Alrik Thiem Post-Doctoral Researcher Department of Philosophy University of Geneva Rue de Candolle 2 CH-1211 Geneva +41 76 527 80 83 http://www.alrik-thiem.net http://www.compasss.org ______________________________________________ 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.