ASKSAGE: Sage Q&A Forum - Individual question feedhttp://ask.sagemath.org/questions/Q&A Forum for SageenCopyright Sage, 2010. Some rights reserved under creative commons license.Tue, 16 Oct 2012 18:30:48 -0500Defining Coxeter groupshttp://ask.sagemath.org/question/9434/defining-coxeter-groups/Is there a way to define a Coxeter group from its matrix so that one can use some of the methods in coxeter_groups? The groups I have in mind are indefinite or hyperbolic.Tue, 16 Oct 2012 05:04:07 -0500http://ask.sagemath.org/question/9434/defining-coxeter-groups/Answer by benjaminfjones for <p>Is there a way to define a Coxeter group from its matrix so that one can use some of the methods in coxeter_groups? The groups I have in mind are indefinite or hyperbolic.</p>
http://ask.sagemath.org/question/9434/defining-coxeter-groups/?answer=14149#post-id-14149There is good support for constructing finite coxeter groups (see also Meinolf Geck's **pycox** module http://homepages.abdn.ac.uk/m.geck/pages/), but in general construction of indefinite Coxeter groups is lacking in Sage.
Of course, if you have a finite presentation or a linear representation of any group you can construct it in Sage using the standard group construction functions, but you aren't necessarily going to be able to compute much with them unless specialized algorithms for them have been implemented (like there are for permutation groups). Tue, 16 Oct 2012 17:45:48 -0500http://ask.sagemath.org/question/9434/defining-coxeter-groups/?answer=14149#post-id-14149Comment by gdkerr for <p>There is good support for constructing finite coxeter groups (see also Meinolf Geck's <strong>pycox</strong>module <a href="http://homepages.abdn.ac.uk/m.geck/pages/">http://homepages.abdn.ac.uk/m.geck/pa...</a>), but in general construction of indefinite Coxeter groups is lacking in Sage. </p>
<p>Of course, if you have a finite presentation or a linear representation of any group you can construct it in Sage using the standard group construction functions, but you aren't necessarily going to be able to compute much with them unless specialized algorithms for them have been implemented (like there are for permutation groups). </p>
http://ask.sagemath.org/question/9434/defining-coxeter-groups/?comment=18855#post-id-18855OK, thanks for the response. Tue, 16 Oct 2012 18:30:48 -0500http://ask.sagemath.org/question/9434/defining-coxeter-groups/?comment=18855#post-id-18855