End Regular.
End RingRepr.
Arguments mx_representation R {gT} G%g n%N.
Arguments mx_repr {R gT} G%g {n%N} r.
Arguments group_ring R {gT} G%g.
Arguments regular_repr R {gT} G%g.
Arguments centgmxP {R gT G n rG f}.
Arguments rkerP {R gT G n rG x}.
Arguments repr_mxK {R gT G%G n%N} rG {m%N} [x%g] Gx.
Arguments repr_mxKV {R gT G%G n%N} rG {m%N} [x%g] Gx.
Arguments gring_valK {gT G%G} i%R : rename.
Arguments gring_indexK {gT G%G} x%g.
Arguments gring_mxK {R gT G%G} v%R : rename.
Section ChangeOfRing.
Variables (aR rR : comUnitRingType) (f : {rmorphism aR -> rR}).
Local Notation "A ^f" := (map_mx (GRing.RMorphism.apply f) A) : ring_scope.
Variables (gT : finGroupType) (G : {group gT}).

(* Specifications: *)
Lemma map_regular_mx x : (regular_mx aR G x)^f = regular_mx rR G x.
Canonical map_repr := MxRepresentation map_mx_repr.