"Source: Text/Group/GrpMatFF.text";
"Line: 636";
"Date: Thu Sep 25 14:47:45 2025";
"Main: Fri Sep 26 14:29:19 2025";
// original file: Text/Group/GrpMatFF.text, line: 636
// Example: H67E3 ()
print "Example: H67E3";
ei := GetEchoInput();
SetEchoInput(true);
P := GL(6,3);
g1 := P![0,1,0,0,0,0,-1,0,0,0,0,0,
         0,0,1,0,0,0,0,0,0,1,0,0,0,0,0,0,1,0,0,0,0,0,0,1];
g2 := P![-1,0,0,0,1,0,0,-1,0,0,0,1,
         -1,0,0,0,0,0,0,-1,0,0,0,0,0,0,-1,0,0,0,0,0,0,-1,0,0];
g3 := P![1,0,0,0,0,0,0,-1,0,0,0,0,
         0,0,1,0,0,0,0,0,0,-1,0,0,0,0,0,0,1,0,0,0,0,0,0,-1];
G := sub <P | g1, g2, g3 >;

IsSemiLinear (G);
assert $1;
DegreeOfFieldExtension (G);
assert $1 eq 2;
CentralisingMatrix (G);
FrobeniusAutomorphisms (G);
K, E, phi := WriteOverLargerField (G);
K.1;
E;

phi;
SetEchoInput(ei);
