Ralf Dentzer asks
But how can I see the relations of an ag group G that I read in from
e.g. the library of solvable groups or the library of 2-groups?
For groups in the 2-group or 3-group library, you access
the field G.abstractRelators described on p. 571 of the manual
gap> G := TwoGroup (32, 5); Group( a1, a2, a3, a4, a5 ) gap> RecFields (G); [ "generators", "identity", "isDomain", "isGroup", "isAgGroup", "cgs", "operations", "1", "2", "3", "4", "5", "rank", "pclass", "abstractGenerators", "abstractRelators" ] gap> G.abstractRelators; [ a1^2*a4^-1, a2^2, a2^-1*a1^-1*a2*a1*a3^-1, a3^2, a3^-1*a1^-1*a3*a1, a3^-1*a2^-1*a3*a2, a4^2*a5^-1, a4^-1*a1^-1*a4*a1, a4^-1*a2^-1*a4*a2, a4^-1*a3^-1*a4*a3, a5^2, a5^-1*a1^-1*a5*a1, a5^-1*a2^-1*a5*a2, a5^-1*a3^-1*a5*a3, a5^-1*a4^-1*a5*a4 ] gap>
He also asks
>P.S. Is there a function to test for isomorphism between two
> ag groups? This would maybe solve my problem, but I
I have implemented an algorithm which in a fair number of cases
allows one to decide whether two given p-groups are isomorphic.
The ANU p-Quotient Program provides access to this implementation.
Part of that program is already accessible as a package in GAP 3.2.
See Chapter 49 of the manual.
The isomorphism testing facility is not yet accessible
within GAP -- it should be available within a few months --
however, it is part of the stand-alone program.
Any interested user should communicate *directly*
with me on this topic.
++++++++++++++++++++++++++++++++++++++++++++++ Eamonn O'Brien ++++++++++++++++++++++++++++++++++++++++++++++ School of Mathematical Sciences Australian National University e-mail email@example.com ++++++++++++++++++++++++++++++++++++++++++++++