Arrays are indexed sequences of indexable sequences of arrays .. to ground.
An array may exist whereof two or more distinct indices find content deemed indistinguishable were it devoid of the indexicalic contextualization that finds. And one may count all the stars were the canopy devoid of of that that finds. One may drop, forget, whatever may be unique of Array or of multiset or of cow. Multisets are a sort of set, one that internalizes some setal structure as cubbies, which is not at all a set of sets. And a common sets are a sort of forgetful multiset, one that forgets mutiplicity. Together, the above is a fruitful basis on which to construct computation; call it Sheaf Theory. "permute *and provide* all possible indistinguishables," not "permute *is provide"*". On Fri, Nov 20, 2015 at 1:32 PM, Stefan Karpinski <ste...@karpinski.org> wrote: > What about the argument that you can always permute indices if you want > all distinct permutations? > > On Fri, Nov 20, 2015 at 1:24 PM, Jiahao Chen <cjia...@gmail.com> wrote: > >> The current behavior of permutations is correct and should not be >> changed. Combinatorially, arrays are multisets, not sets, since they allow >> for duplicate entries, so it is correct to produce what look like identical >> permutations. The redundancy is important for operations that can be >> expressed as sums over all permutations. >> >> Combinatorics.jl currently provides multiset_permutations for generating >> only distinct permutations: >> >> >> https://github.com/JuliaLang/Combinatorics.jl/blob/3c08c9af9ebeaa54589e939c0cf2e652ef4ca6a0/test/permutations.jl#L24-L25 >> > >
