Definition map_mx_sum := big_morph _ map_mxD map_mx0.Canonical map_mx_additive := Additive map_mx_sub.Fact scalemx_key : unit.Definition scalemx x A := \matrix[scalemx_key]_(i, j) (x * A i j).(* Basis *)
Fact delta_mx_key : unit.Definition matrix_lmodMixin := 
  LmodMixin scalemxA scale1mx scalemxDr scalemxDl.Canonical matrix_lmodType :=
  Eval hnf in LmodType R 'M[R]_(m, n) matrix_lmodMixin.

Lemma swizzle_mx_is_scalable m n p q f g k : scalable (@swizzle_mx R m n p q f g k).