fact: Definition mx_ent := filter_from [set P : 'I_m -> 'I_n -> set (T * T) | forall i j, entourage (P i j)] (fun P => [set MN : 'M[T]_(m, n) * 'M[T]_(m, n) | forall i j, P i j (MN.1 i j, MN.2 i j)]).
imports: HB(structures) mathcomp(all_ssreflect all_algebra finmap generic_quotient) mathcomp(boolp classical_sets functions) mathcomp(cardinality mathcomp_extra fsbigop) reals signed