1LoadPackage( "RingsForHomalg" ); 2 3LoadPackage( "Modules" ); 4 5Qxy := HomalgFieldOfRationalsInDefaultCAS( ) * "x,y"; 6 7YI := HomalgMatrix( "[ \ 8y^2-x*(x-1)*(x+1), 0, 0, \ 90, x, 0, \ 100, y, 0, \ 110, 0, x, \ 120, 0, y-1 \ 13]", 5, 3, Qxy ); 14 15Y := LeftPresentation( Involution( YI ) ); 16 17Yt := TorsionObject( Y ); 18 19Ann := Annihilator( Yt ); 20