Experimental Systems & Systems in Development


AUTOMATA is a package that for a given finitely presented group attempts to construct the finite state automata associated with a lex-least automatic structure of this group and verifies axioms for an automatic group. The programs were written by David Epstein, Derek Holt (University of Warwick) and Sarah Rees (University of Newcastle).

QUOTPIC is an X-Windows program for plotting the finite quotients of a finitely presented group. It builds the quotients via descending series of normal subgroups. More details about QUOTPIC can be found in: Derek F Holt and Sarah Rees, `A graphics system for displaying finite quotients of finitely presented groups', Proc. DIMACS Workshop on Groups and Computation, AMS-ACM 1991.

The program TESTISOM takes as input two finitely presented groups and attempts to decide whether they are isomorphic or not. It alternately attempts to construct an explicit isomorphism, and (if this fails) to prove nonisomorphism by finding distinct finite quotients of the two groups. More details about TESTISOM can be found in: D.F.Holt and Sarah Rees, `Testing for isomorphism between finitely presented groups', in Groups, Combinatorics and Geometry, ed. M.W.Liebeck and J.S.Saxl, London Mathematical Society Lecture Note Series 165, pp 459-475, CUP 1992.

The programs QUOTPIC and TESTISOM were written by Derek Holt (University of Warwick) and Sarah Rees (University of Newcastle).

All three packages are available by anonymous ftp at ftp.ncl.ac.uk:/pub/local/nser.

Experimental Systems


Last updated: December 21, 1994