On 2013-03-21, Nils Bruin <nbr...@sfu.ca> wrote: > On Mar 21, 9:05 am, Benjamin Jones <benjaminfjo...@gmail.com> wrote: >> It seems to me that the ambiguity arises from the original statement, > > Systems like magma (and I assume gap as well) solve this by having a > "GSet" type. If you have S3 acting on the GSet V={1,2,3} then, one can > construct the powerset W of V as a GSet as well. In that context there > is a natural distinction between the subset {1,2,3} of V (which is a > sub-GSet) and the element {1,2,3} of W. On GAP there is nothing like GSet. As far as I know, one needs to do that "boxing" trick I explained there, too, if one needs to "mix" things in the domain of the group.
> > One can talk about the orbit of the element {1,2} in W under S3 but > obviously, {1,2} is not a sub-GSet of V. > > How these things coerce between each other is another matter, but I > suspect making such distinctions internally is unavoidable. Many years ago I abandoned Magma's predecessor, Cayley, for GAP, as Cayley's lack of proper coersions/conversions drove me insane all the time. Dima -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel?hl=en. For more options, visit https://groups.google.com/groups/opt_out.