(** mappings between Q and Z *)

Lemma Z_to_Qpositive_equal :
forall (m1 m2 : Z) (Hm1 : (0 < m1)%Z) (Hm2 : (0 < m2)%Z),
m1 = m2 -> Z_to_Qpositive m1 Hm1 = Z_to_Qpositive m2 Hm2.