proposition: Lemma zPos: (0 <= z)%R.
proof: Proof. unfold FtoRradix; apply RleRoundedR0 with bo p (Closest bo radix) (a*x+b)%R; auto with zarith. apply ClosestRoundedModeP with p; auto with zarith. Qed.
imports: Reals ZArith List PeanoNat Psatz