[GAP Forum] Possible bug with MinimalGeneratingSet()???

[Joe Bohanon]

Greg and Forum

You might find this link particularly helpful here:

http://mail.gap-system.org/pipermail/forum/2005/001109.html

For non-solvable groups, you can (sort of) get what you want with
"SmallGeneratingSet".  I would guess from the name that it's not necessarily
"Minimal", however, it can be very useful if you define a non-solvable
group, then try (for instance) asking for the center, and you get a subgroup
with 2 elements and 35 generators (I swear, I've seen that happen before).
In my experience, it does very well with permutation groups.  With groups
you define yourself via generators and relations, anything goes.

Joe

On Sun, Jun 6, 2010 at 10:15 PM, Greg Tener <greg.d.tener at gmail.com> wrote:

> Dear GAP-forum,
>
> There might be a problem with MinimalGeneratingSet().  It seems not to
> work for a particular group, as shown in the following console
> session:
>
> """
> gap> g := Group( [ (1,2,3,4,5), (1,2,3) ] );
> Group([ (1,2,3,4,5), (1,2,3) ])
> gap> MinimalGeneratingSet(g);
> Error, no method found! For debugging hints type ?Recovery from
> NoMethodFound
> Error, no 2nd choice method found for
> `IndependentGeneratorsOfAbelianGroup' on 1 arguments called from
> IndependentGeneratorsOfAbelianGroup( G ) called from
> <function>( <arguments> ) called from read-eval-loop
> Entering break read-eval-print loop ...
> you can 'quit;' to quit to outer loop, or
> you can 'return;' to continue
> """
>
> Am I doing something wrong or could this be a bug? I know nothing
> about the internals of GAP so I cannot think why this would happen or
> how to fix it.
>
> Thanks,
> -Greg Tener-
>
> _______________________________________________
> Forum mailing list
> Forum at mail.gap-system.org
> http://mail.gap-system.org/mailman/listinfo/forum
>