Dear Frédéric, Dear GAP-Forum, > but this doesn't work; > > LoadPackage("grape"); > q:=13; > gf:=GaloisField(q); > graph:=Graph(Group(()), Elements(gf), OnPoints,function(x,y) return > (x-y)^((q-1)/2)=One(gf); end,true); > > It's probably just a matter of defining the trivial group on the > right set in the proper way, but how should one do this?
What I suggest is to define a function for the trivial action of a group: trivialaction := function(x,g) return x; end; Then the following will work: LoadPackage("grape"); q:=13; gf:=GaloisField(q); graph:=Graph(Group(()), Elements(gf), trivialaction, function(x,y) return (x-y)^((q-1)/2)=One(gf); end,true); All the best, Leonard _______________________________________________ Forum mailing list Forum@mail.gap-system.org http://mail.gap-system.org/mailman/listinfo/forum