NEW: Abelian version of MTC. Use in `AbelianInvariants' for subgp.

Removed library code for old version that is now obsolete.

lib/ghomfp.gi

@@ -218,16 +218,7 @@ local u,aug,hgu,mapi,w;
  aug.primaryImages:=List(aug.subgens,
  i->aug.homgenims[Position(hgu,i)]);
 
- # # try to re-use an existing augmented coset table:
- # aug:=AugmentedCosetTableInWholeGroup(u,mapi[1]);
- # if not IsSubset(hgu,aug.primaryGeneratorWords) then
- # # we don't know what to do with the extra primary words, so enforce MTC
- # # version
- # aug:=AugmentedCosetTableMtcInWholeGroup(
- # SubgroupNC(FamilyObj(u)!.wholeGroup,mapi[1]));
- # fi;
- # as we add homomorphism specific entries, lets be safe and copy.
- # aug:=CopiedAugmentedCosetTable(aug);
+ # TODO: possibly re-use an existing augmented table stored already
 
  TrySecondaryImages(aug);
 
@@ -881,29 +872,6 @@ local aug,w,p,pres,f,fam,G;
  fi;
  Assert(0,Length(GeneratorsOfPresentation(pres))=Length(gens));
 
- # old code
-# if HasGeneratorsOfGroup(u) and IsIdenticalObj(GeneratorsOfGroup(u),gens) then
-# aug:=AugmentedCosetTableMtcInWholeGroup(u);
-# else
-# w:=FamilyObj(u)!.wholeGroup;
-# aug:=AugmentedCosetTableMtc(w,SubgroupNC(w,gens),2,"%");
-# # do not store the generators for the subgroup (the user could do this
-# # himself if he wanted), the danger of consequential errors due to a
-# # wrong <gens> list is too high.
-# fi;
-#
-# # force computation of words for the secondary generators
-# SecondaryGeneratorWordsAugmentedCosetTable(aug);
-#
-# # create a tietze object to reduce the presentation a bit
-# if not IsBound(aug.subgroupRelators) then
-# aug.subgroupRelators := RewriteSubgroupRelators( aug, aug.groupRelators);
-# fi;
-# aug:=CopiedAugmentedCosetTable(aug);
-# pres := PresentationAugmentedCosetTable( aug,nam,0,true );
-# TzOptions(pres).printLevel:=InfoLevel(InfoFpGroup);
-# DecodeTree(pres);
-
  # new free group
  f:=FpGroupPresentation(pres);
  aug.homgens:=gens;