diff options
Diffstat (limited to 'theories/Numbers/Cyclic/DoubleCyclic/DoubleSqrt.v')
-rw-r--r-- | theories/Numbers/Cyclic/DoubleCyclic/DoubleSqrt.v | 29 |
1 files changed, 8 insertions, 21 deletions
diff --git a/theories/Numbers/Cyclic/DoubleCyclic/DoubleSqrt.v b/theories/Numbers/Cyclic/DoubleCyclic/DoubleSqrt.v index 4394178f..b073d6be 100644 --- a/theories/Numbers/Cyclic/DoubleCyclic/DoubleSqrt.v +++ b/theories/Numbers/Cyclic/DoubleCyclic/DoubleSqrt.v @@ -1,6 +1,6 @@ (************************************************************************) (* v * The Coq Proof Assistant / The Coq Development Team *) -(* <O___,, * INRIA - CNRS - LIX - LRI - PPS - Copyright 1999-2011 *) +(* <O___,, * INRIA - CNRS - LIX - LRI - PPS - Copyright 1999-2010 *) (* \VV/ **************************************************************) (* // * This file is distributed under the terms of the *) (* * GNU Lesser General Public License Version 2.1 *) @@ -8,8 +8,6 @@ (* Benjamin Gregoire, Laurent Thery, INRIA, 2007 *) (************************************************************************) -(*i $Id: DoubleSqrt.v 14641 2011-11-06 11:59:10Z herbelin $ i*) - Set Implicit Arguments. Require Import ZArith. @@ -220,12 +218,8 @@ Section DoubleSqrt. Variable spec_w_0W : forall l, [[w_0W l]] = [|l|]. Variable spec_w_is_even : forall x, if w_is_even x then [|x|] mod 2 = 0 else [|x|] mod 2 = 1. - Variable spec_w_compare : forall x y, - match w_compare x y with - | Eq => [|x|] = [|y|] - | Lt => [|x|] < [|y|] - | Gt => [|x|] > [|y|] - end. + Variable spec_w_compare : forall x y, + w_compare x y = Zcompare [|x|] [|y|]. Variable spec_w_sub : forall x y, [|w_sub x y|] = ([|x|] - [|y|]) mod wB. Variable spec_w_square_c : forall x, [[ w_square_c x]] = [|x|] * [|x|]. Variable spec_w_div21 : forall a1 a2 b, @@ -257,11 +251,7 @@ Section DoubleSqrt. Variable spec_ww_pred : forall x, [[ww_pred x]] = ([[x]] - 1) mod wwB. Variable spec_ww_add_c : forall x y, [+[ww_add_c x y]] = [[x]] + [[y]]. Variable spec_ww_compare : forall x y, - match ww_compare x y with - | Eq => [[x]] = [[y]] - | Lt => [[x]] < [[y]] - | Gt => [[x]] > [[y]] - end. + ww_compare x y = Zcompare [[x]] [[y]]. Variable spec_ww_head0 : forall x, 0 < [[x]] -> wwB/ 2 <= 2 ^ [[ww_head0 x]] * [[x]] < wwB. Variable spec_low: forall x, [|low x|] = [[x]] mod wB. @@ -299,10 +289,7 @@ intros x; case x; simpl ww_is_even. apply Zlt_le_trans with (2 := Hb); auto with zarith. apply Zlt_le_trans with 1; auto with zarith. apply Zdiv_le_lower_bound; auto with zarith. - repeat match goal with |- context[w_compare ?y ?z] => - generalize (spec_w_compare y z); - case (w_compare y z) - end. + rewrite !spec_w_compare. repeat case Zcompare_spec. intros H1 H2; split. unfold interp_carry; autorewrite with w_rewrite rm10; auto with zarith. rewrite H1; rewrite H2; ring. @@ -1108,12 +1095,12 @@ intros x; case x; simpl ww_is_even. rewrite wwB_wBwB; rewrite Zpower_2. apply Zmult_le_compat_r; auto with zarith. case (spec_to_Z w4);auto with zarith. - Qed. +Qed. Lemma spec_ww_is_zero: forall x, if ww_is_zero x then [[x]] = 0 else 0 < [[x]]. intro x; unfold ww_is_zero. - generalize (spec_ww_compare W0 x); case (ww_compare W0 x); + rewrite spec_ww_compare. case Zcompare_spec; auto with zarith. simpl ww_to_Z. assert (V4 := spec_ww_to_Z w_digits w_to_Z spec_to_Z x);auto with zarith. @@ -1198,7 +1185,7 @@ intros x; case x; simpl ww_is_even. simpl ww_to_Z; simpl Zpower; unfold Zpower_pos; simpl; auto with zarith. intros H1. - generalize (spec_ww_compare (ww_head1 x) W0); case ww_compare; + rewrite spec_ww_compare. case Zcompare_spec; simpl ww_to_Z; autorewrite with rm10. generalize H1; case x. intros HH; contradict HH; simpl ww_to_Z; auto with zarith. |