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oscar-system · Apr 17, 2024 · 44868aa · 44868aa
1 parent 5403e06
commit 44868aa
Showing 1 changed file with 5 additions and 0 deletions.
diff --git a/src/Groups/homomorphisms.jl b/src/Groups/homomorphisms.jl
@@ -547,6 +547,11 @@ function isomorphism(::Type{FPGroup}, G::GAPGroup; on_gens::Bool=false)
          if GAP.Globals.HasFamilyPcgs(G.X)
            pcgs = GAP.Globals.InducedPcgsWrtFamilyPcgs(G.X)
            if pcgs == Ggens
+             # `pcgs` fits *and* is an object in `GAP.Globals.IsPcgs`,
+             # for which a special `GAPWrap.IsomorphismFpGroupByGenerators`
+             # method is applicable.
+             # (Currently the alternative is a cokernel computation.
+             # It might be useful to improve this on the GAP side.)
              Ggens = pcgs
            end
          end