id summary reporter owner description type status priority milestone component resolution keywords cc merged author reviewer upstream work_issues branch commit dependencies stopgaps
4115 [with patch, positive review] Double coset problems Robert Miller Robert Miller "Implements computations of properties which form double cosets. For example, if G is isomorphic to H, and m : G -> H is an isomorphism, then the set of all isomorphisms is the double coset Aut(H) m Aut(G).
This algorithm is pretty close to the canonical label algorithm, but it is a more efficient way to implement the isomorphism question. If the objects are not isomorphic, it will tend to discover this pretty quickly, via refinement invariants and examining the partition structure. If they are isomorphic, chances are this isomorphism will be discovered quickly and the algorithm will terminate at that moment." defect closed major sage-3.1.3 group theory fixed N/A