a = perms(1:4);a(a==2)=1;a(a==3)=0;a(a==4)=0;unique(a);b = unique(a,'rows')';[m,n] = size(b);N = 3;R = [];for p = 1:N id = randperm(n); r = b(:,id); id = randperm(m); r = r(id,:); R = [R r];endR = sparse(R)nnz(R)