Hi Martin I've also tried your code and must confirm Waldek's statements. I guess there are some pitfalls which are known for some time.
Did you read "Implementation and Analysis of the Todd-Coxeter Algorithm" by Cannon et al.? Old but still beneficial. http://staff.itee.uq.edu.au/havas/1973cdhw.pdf Maybe you should alo have a look at sympy: http://docs.sympy.org/dev/modules/combinatorics/fp_groups.html where the article above is also cited. Otherwise I see much progress. Kurt Am 26.01.2017 um 15:29 schrieb Waldek Hebisch: > Martin Baker wrote: >> >> On 01/25/2017 05:23 AM, Waldek Hebisch wrote: >>> I also noticed that Todd-Coxeter (toPermutationIfCan) >>> may produce something strange. Namely, the following >>> (junky) relations: >> > > ATM I do not know what is good strategy when implementing > Todd-Coxeter. One thing that I know is that it is > useful to work with cosets with respect to a nontrivial > subgroup. > -- You received this message because you are subscribed to the Google Groups "FriCAS - computer algebra system" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/fricas-devel. For more options, visit https://groups.google.com/d/optout.
