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|
gap> START_TEST("Test of isomorphisms from/to pcp groups");
#
# Extreme case: Test with trivial group
#
gap> K:=TrivialGroup(IsPcpGroup);
Pcp-group with orders [ ]
gap> iso:=IsomorphismPcGroup(K);
[ ] -> [ ]
gap> IsTrivial(Image(iso));
true
gap> iso:=IsomorphismPermGroup(K);
[ ] -> [ ]
gap> IsTrivial(Image(iso));
true
gap> iso:=IsomorphismFpGroup(K);
[ ] -> [ ]
gap> IsTrivial(Image(iso));
true
#
gap> iso:=IsomorphismPcpGroup(TrivialGroup(IsPcGroup));
[ ] -> [ ]
gap> IsTrivial(Image(iso));
true
#
gap> iso:=IsomorphismPcpGroup(TrivialGroup(IsPermGroup));
[ ] -> [ ]
gap> IsTrivial(Image(iso));
true
#
# Test with finite cyclic group
#
gap> K:=CyclicGroup(IsPcpGroup, 420);
Pcp-group with orders [ 420 ]
#
gap> iso:=IsomorphismPcGroup(K);
[ g1 ] -> [ f1 ]
gap> Size(Image(iso));
420
gap> IsCyclic(Image(iso));
true
#
gap> iso:=IsomorphismPermGroup(K);;
gap> Size(Image(iso));
420
gap> IsCyclic(Image(iso));
true
#
gap> iso:=IsomorphismFpGroup(K);
[ g1 ] -> [ f1 ]
gap> Size(Image(iso));
420
gap> IsCyclic(Image(iso));
true
#
# Test with infinite cyclic group
#
gap> K:=CyclicGroup(IsPcpGroup, infinity);
Pcp-group with orders [ 0 ]
gap> iso:=IsomorphismFpGroup(K);
[ g1 ] -> [ f1 ]
gap> IsCyclic(Image(iso));
true
gap> IsFinite(Image(iso));
false
#
# Test with dihedral group
#
gap> K:=DihedralGroup(IsPcpGroup, 16);;
gap> IdSmallGroup(K);
[ 16, 7 ]
gap> iso:=IsomorphismPermGroup(K);;
gap> IdSmallGroup(Image(iso));
[ 16, 7 ]
gap> iso:=IsomorphismPcGroup(K);;
gap> IdSmallGroup(Image(iso));
[ 16, 7 ]
gap> iso:=IsomorphismFpGroup(K);;
gap> IdSmallGroup(Image(iso));
[ 16, 7 ]
#
gap> STOP_TEST( "homs.tst", 10000000);
|
