Global Opaque Rcompare.

(* Specifications: *)
Theorem Rcompare_Lt :
forall x y,
(x < y)%R -> Rcompare x y = Lt.
Theorem Rcompare_Lt_inv :
forall x y,
Rcompare x y = Lt -> (x < y)%R.
Theorem Rcompare_not_Lt :
forall x y,
(y <= x)%R -> Rcompare x y <> Lt.
Theorem Rcompare_not_Lt_inv :
forall x y,
Rcompare x y <> Lt -> (y <= x)%R.
Theorem Rcompare_Eq :
forall x y,
x = y -> Rcompare x y = Eq.
Theorem Rcompare_Eq_inv :
forall x y,
Rcompare x y = Eq -> x = y.
Theorem Rcompare_Gt :
forall x y,
(y < x)%R -> Rcompare x y = Gt.
Theorem Rcompare_Gt_inv :
forall x y,
Rcompare x y = Gt -> (y < x)%R.
Theorem Rcompare_not_Gt :
forall x y,
(x <= y)%R -> Rcompare x y <> Gt.
Theorem Rcompare_not_Gt_inv :
forall x y,
Rcompare x y <> Gt -> (x <= y)%R.
Theorem Rcompare_Z2R :
forall x y, Rcompare (Z2R x) (Z2R y) = Zcompare x y.
Theorem Rcompare_sym :
forall x y,
Rcompare x y = CompOpp (Rcompare y x).
Theorem Rcompare_plus_r :
forall z x y,
Rcompare (x + z) (y + z) = Rcompare x y.
Theorem Rcompare_plus_l :
forall z x y,
Rcompare (z + x) (z + y) = Rcompare x y.
Theorem Rcompare_mult_r :
forall z x y,
(0 < z)%R ->
Rcompare (x * z) (y * z) = Rcompare x y.
Theorem Rcompare_mult_l :
forall z x y,
(0 < z)%R ->
Rcompare (z * x) (z * y) = Rcompare x y.
Theorem Rcompare_middle :
forall x d u,
Rcompare (x - d) (u - x) = Rcompare x ((d + u) / 2).
Theorem Rcompare_half_l :
forall x y, Rcompare (x / 2) y = Rcompare x (2 * y).
Theorem Rcompare_half_r :
forall x y, Rcompare x (y / 2) = Rcompare (2 * x) y.
Theorem Rcompare_sqr :
forall x y,
(0 <= x)%R -> (0 <= y)%R ->
Rcompare (x * x) (y * y) = Rcompare x y.
Theorem Rmin_compare :
forall x y,
Rmin x y = match Rcompare x y with Lt => x | Eq => x | Gt => y end.