ENHANCE: EpimorphismSolvableQuotient sets injective

if source size is known and equals image size. This fixes gap-system#3431
hulpke · May 14, 2019 · 8a95e01 · 8a95e01
1 parent 0e92e18
commit 8a95e01
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/lib/grppcfp.gi b/lib/grppcfp.gi
@@ -878,6 +878,9 @@ local g, sq, hom;
   g:=arg[1];
   sq:=CallFuncList(SQ,arg);
   hom:=GroupHomomorphismByImages(g,sq.image,GeneratorsOfGroup(g),sq.imgs);
+  if HasSize(g) and Size(g)=Size(sq.image) then
+    SetIsInjective(hom,true);
+  fi;
   return hom;
 end);