aboutsummaryrefslogtreecommitdiff
path: root/theories/setoid_ring/Rings_Q.v
diff options
context:
space:
mode:
Diffstat (limited to 'theories/setoid_ring/Rings_Q.v')
-rw-r--r--theories/setoid_ring/Rings_Q.v41
1 files changed, 41 insertions, 0 deletions
diff --git a/theories/setoid_ring/Rings_Q.v b/theories/setoid_ring/Rings_Q.v
new file mode 100644
index 0000000000..b3ed0be916
--- /dev/null
+++ b/theories/setoid_ring/Rings_Q.v
@@ -0,0 +1,41 @@
+(************************************************************************)
+(* * The Coq Proof Assistant / The Coq Development Team *)
+(* v * INRIA, CNRS and contributors - Copyright 1999-2019 *)
+(* <O___,, * (see CREDITS file for the list of authors) *)
+(* \VV/ **************************************************************)
+(* // * This file is distributed under the terms of the *)
+(* * GNU Lesser General Public License Version 2.1 *)
+(* * (see LICENSE file for the text of the license) *)
+(************************************************************************)
+
+Require Export Cring.
+Require Export Integral_domain.
+
+(* Rational numbers *)
+Require Import QArith.
+
+Instance Qops: (@Ring_ops Q 0%Q 1%Q Qplus Qmult Qminus Qopp Qeq).
+Defined.
+
+Instance Qri : (Ring (Ro:=Qops)).
+constructor.
+try apply Q_Setoid.
+apply Qplus_comp.
+apply Qmult_comp.
+apply Qminus_comp.
+apply Qopp_comp.
+ exact Qplus_0_l. exact Qplus_comm. apply Qplus_assoc.
+ exact Qmult_1_l. exact Qmult_1_r. apply Qmult_assoc.
+ apply Qmult_plus_distr_l. intros. apply Qmult_plus_distr_r.
+reflexivity. exact Qplus_opp_r.
+Defined.
+
+Instance Qcri: (Cring (Rr:=Qri)).
+red. exact Qmult_comm. Defined.
+
+Lemma Q_one_zero: not (Qeq 1%Q 0%Q).
+unfold Qeq. simpl. auto with *. Qed.
+
+Instance Qdi : (Integral_domain (Rcr:=Qcri)).
+constructor.
+exact Qmult_integral. exact Q_one_zero. Defined.