Hello. Given this group assignment vector x: x= rep(letters[1:3],c(9,21,9))
I would like to know the number of all possible unique permutations of x and also obtain the matrix of them. Thus, each vector should still contain 9*a, 21*b and 9*c, but case assigment must be different for one case (default at least 2) for each permuation. a, b and c can be interspersed in permuted vectors, i.e. order does not matter. If this unique permutation matrix is very large then I would like to choose a subset of it. I can easily permute the vector with sample(x) but if I repeat this n>1 times there is no guarantee of uniqueness. For a small number of samples, I could look for unique vectors and keep only those but this seems awkward and I suspect there are more elegant ways to do it. Is there an r function which will allow me to calculate both how many unique permutations of x exist and also obtain a matrix of them and/or a subset of that matrix? Thanks very much, Daniel ______________________ Daniel Duplisea Pêches et Océans / Fisheries and Oceans Canada Institut Maurice-Lamontagne Mont-Joli, QC G5H 3Z4 Canada tel: 1 418 775 0881 fax: 1 418 775 0740 ______________________________________________ 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.
