Orbit() of a matrix group on sets of vectors stopped working in GAP 4.13 #5786
Description
Observed behaviour
with GAP 4.13.0 or .1, the following stopped working
gap> gg:=SpecialUnitaryGroup(4,2);
SU(4,2)
gap> hl:=Z(2)*[
> [0,0,1,0],
> [1,1,0,0],
> [0,1,0,1],
> [0,1,1,0],
> [1,1,0,1]];
[ [ 0*Z(2), 0*Z(2), Z(2)^0, 0*Z(2) ], [ Z(2)^0, Z(2)^0, 0*Z(2), 0*Z(2) ], [ 0*Z(2), Z(2)^0, 0*Z(2), Z(2)^0 ], [ 0*Z(2), Z(2)^0, Z(2)^0, 0*Z(2) ], [ Z(2)^0, Z(2)^0, 0*Z(2), Z(2)^0 ] ]
gap> o216:=Orbit(gg,Set(hl),OnSets);
Error, no method found! For debugging hints type ?Recovery from NoMethodFound
Error, no 1st choice method found for `+' on 2 arguments
The 2nd argument is 'fail' which might point to an earlier problem
at /mnt/opt/gap/lib/methsel2.g:250 called from
pow * gsy + fct( i ) at /mnt/opt/gap/lib/dicthf.gi:184 called from
hash!.intKeyFun( key ) at /mnt/opt/gap/lib/dict.gi:897 called from
LookupDictionary( ht, x ) at /mnt/opt/gap/lib/dict.gi:886 called from
KnowsDictionary( d, i ) at /mnt/opt/gap/lib/oprt.gi:1024 called from
orbish( G, pnt, gens, acts, act ) at /mnt/opt/gap/lib/oprt.gd:858 called from
... at *stdin*:8
type 'quit;' to quit to outer loop
Expected behaviour
Orbit gets created (the above commands work with GAP 4.12.2 and earlier)
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┌───────┐ GAP 4.13.1 of 2024-06-11
│ GAP │ https://www.gap-system.org
└───────┘ Architecture: amd64
Configuration: gmp 6.3.0, GASMAN, readline
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