X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fsoftware%2Fmatita%2Fdama%2Fordered_group.ma;h=9b70c4f6219298601cb53bbd748047042371d06a;hb=3a5b9647787e1402f6886d41824f664db290963f;hp=d2f96fb5c7c03faf6fdb1b76774fd49dd8c86c14;hpb=39c55604f8114e2e8f9f9769acd328de8f19c7e4;p=helm.git

diff --git a/helm/software/matita/dama/ordered_group.ma b/helm/software/matita/dama/ordered_group.ma
index d2f96fb5c..9b70c4f62 100644
--- a/helm/software/matita/dama/ordered_group.ma
+++ b/helm/software/matita/dama/ordered_group.ma
@@ -12,34 +12,33 @@
 (*                                                                        *)
 (**************************************************************************)
 
-set "baseuri" "cic:/matita/ordered_gorup/".
+set "baseuri" "cic:/matita/ordered_group/".
 
-include "ordered_set.ma".
 include "group.ma".
 
-record pre_ogroup : Type ≝ { 
+record pogroup_ : Type ≝ { 
   og_abelian_group_: abelian_group;
-  og_tordered_set:> tordered_set;
-  og_with: carr og_abelian_group_ = og_tordered_set
+  og_excedence:> excedence;
+  og_with: carr og_abelian_group_ = apart_of_excedence og_excedence
 }.
 
-lemma og_abelian_group: pre_ogroup → abelian_group.
+lemma og_abelian_group: pogroup_ → abelian_group.
 intro G; apply (mk_abelian_group G); [1,2,3: rewrite < (og_with G)]
 [apply (plus (og_abelian_group_ G));|apply zero;|apply opp]
-unfold apartness_OF_pre_ogroup; cases (og_with G); simplify;
+unfold apartness_OF_pogroup_; cases (og_with G); simplify;
 [apply plus_assoc|apply plus_comm|apply zero_neutral|apply opp_inverse|apply plus_strong_ext]
 qed.
 
-coercion cic:/matita/ordered_gorup/og_abelian_group.con.
+coercion cic:/matita/ordered_group/og_abelian_group.con.
 
-record ogroup : Type ≝ { 
-  og_carr:> pre_ogroup;
-  exc_canc_plusr: ∀f,g,h:og_carr. f+h ≰ g+h → f ≰ g
+record pogroup : Type ≝ { 
+  og_carr:> pogroup_;
+  plus_cancr_exc: ∀f,g,h:og_carr. f+h ≰ g+h → f ≰ g
 }.
 
 lemma fexc_plusr: 
-  ∀G:ogroup.∀x,y,z:G. x ≰ y → x+z ≰ y + z.
-intros 5 (G x y z L); apply (exc_canc_plusr ??? (-z));
+  ∀G:pogroup.∀x,y,z:G. x ≰ y → x+z ≰ y + z.
+intros 5 (G x y z L); apply (plus_cancr_exc ??? (-z));
 apply (Ex≪  (x + (z + -z)) (plus_assoc ????));
 apply (Ex≪  (x + (-z + z)) (plus_comm ??z));
 apply (Ex≪  (x+0) (opp_inverse ??));
@@ -52,17 +51,17 @@ apply (Ex≫  (0+y) (plus_comm ???));
 apply (Ex≫  y (zero_neutral ??) L);
 qed.
 
-coercion cic:/matita/ordered_gorup/fexc_plusr.con nocomposites.
+coercion cic:/matita/ordered_group/fexc_plusr.con nocomposites.
 
-lemma exc_canc_plusl: ∀G:ogroup.∀f,g,h:G. h+f ≰ h+g → f ≰ g.
-intros 5 (G x y z L); apply (exc_canc_plusr ??? z);
+lemma plus_cancl_exc: ∀G:pogroup.∀f,g,h:G. h+f ≰ h+g → f ≰ g.
+intros 5 (G x y z L); apply (plus_cancr_exc ??? z);
 apply (exc_rewl ??? (z+x) (plus_comm ???));
 apply (exc_rewr ??? (z+y) (plus_comm ???) L);
 qed.
 
 lemma fexc_plusl: 
-  ∀G:ogroup.∀x,y,z:G. x ≰ y → z+x ≰ z+y.
-intros 5 (G x y z L); apply (exc_canc_plusl ??? (-z));
+  ∀G:pogroup.∀x,y,z:G. x ≰ y → z+x ≰ z+y.
+intros 5 (G x y z L); apply (plus_cancl_exc ??? (-z));
 apply (exc_rewl ???? (plus_assoc ??z x));
 apply (exc_rewr ???? (plus_assoc ??z y));
 apply (exc_rewl ??? (0+x) (opp_inverse ??));
@@ -71,10 +70,10 @@ apply (exc_rewl ???? (zero_neutral ??));
 apply (exc_rewr ???? (zero_neutral ??) L);
 qed.
 
-coercion cic:/matita/ordered_gorup/fexc_plusl.con nocomposites.
+coercion cic:/matita/ordered_group/fexc_plusl.con nocomposites.
 
 lemma plus_cancr_le: 
-  ∀G:ogroup.∀x,y,z:G.x+z ≤ y + z → x ≤ y.
+  ∀G:pogroup.∀x,y,z:G.x+z ≤ y + z → x ≤ y.
 intros 5 (G x y z L);
 apply (le_rewl ??? (0+x) (zero_neutral ??));
 apply (le_rewl ??? (x+0) (plus_comm ???));
@@ -86,10 +85,10 @@ apply (le_rewr ??? (y+0) (plus_comm ???));
 apply (le_rewr ??? (y+(-z+z)) (opp_inverse ??));
 apply (le_rewr ??? (y+(z+ -z)) (plus_comm ??z));
 apply (le_rewr ??? (y+z+ -z) (plus_assoc ????));
-intro H; apply L; clear L; apply (exc_canc_plusr ??? (-z) H);
+intro H; apply L; clear L; apply (plus_cancr_exc ??? (-z) H);
 qed.
 
-lemma fle_plusl: ∀G:ogroup. ∀f,g,h:G. f≤g → h+f≤h+g.
+lemma fle_plusl: ∀G:pogroup. ∀f,g,h:G. f≤g → h+f≤h+g.
 intros (G f g h);
 apply (plus_cancr_le ??? (-h));
 apply (le_rewl ??? (f+h+ -h) (plus_comm ? f h));
@@ -106,13 +105,13 @@ apply (le_rewr ??? (0+g) (plus_comm ???));
 apply (le_rewr ??? (g) (zero_neutral ??) H);
 qed.
 
-lemma fle_plusr: ∀G:ogroup. ∀f,g,h:G. f≤g → f+h≤g+h.
+lemma fle_plusr: ∀G:pogroup. ∀f,g,h:G. f≤g → f+h≤g+h.
 intros (G f g h H); apply (le_rewl ???? (plus_comm ???)); 
 apply (le_rewr ???? (plus_comm ???)); apply fle_plusl; assumption;
 qed.
 
 lemma plus_cancl_le: 
-  ∀G:ogroup.∀x,y,z:G.z+x ≤ z+y → x ≤ y.
+  ∀G:pogroup.∀x,y,z:G.z+x ≤ z+y → x ≤ y.
 intros 5 (G x y z L);
 apply (le_rewl ??? (0+x) (zero_neutral ??));
 apply (le_rewl ??? ((-z+z)+x) (opp_inverse ??));
@@ -123,39 +122,68 @@ apply (le_rewr ??? (-z+(z+y)) (plus_assoc ????));
 apply (fle_plusl ??? (-z) L);
 qed.
 
+lemma plus_cancl_lt: 
+  ∀G:pogroup.∀x,y,z:G.z+x < z+y → x < y.
+intros 5 (G x y z L); elim L (A LE); split; [apply plus_cancl_le; assumption]
+apply (plus_cancl_ap ???? LE);
+qed.
+
+lemma plus_cancr_lt: 
+  ∀G:pogroup.∀x,y,z:G.x+z < y+z → x < y.
+intros 5 (G x y z L); elim L (A LE); split; [apply plus_cancr_le; assumption]
+apply (plus_cancr_ap ???? LE);
+qed.
+
+
 lemma exc_opp_x_zero_to_exc_zero_x: 
-  ∀G:ogroup.∀x:G.-x ≰ 0 → 0 ≰ x.
-intros (G x H); apply (exc_canc_plusr ??? (-x));
+  ∀G:pogroup.∀x:G.-x ≰ 0 → 0 ≰ x.
+intros (G x H); apply (plus_cancr_exc ??? (-x));
 apply (exc_rewr ???? (plus_comm ???));
 apply (exc_rewr ???? (opp_inverse ??));
 apply (exc_rewl ???? (zero_neutral ??) H);
 qed.
   
 lemma le_zero_x_to_le_opp_x_zero: 
-  ∀G:ogroup.∀x:G.0 ≤ x → -x ≤ 0.
+  ∀G:pogroup.∀x:G.0 ≤ x → -x ≤ 0.
 intros (G x Px); apply (plus_cancr_le ??? x);
 apply (le_rewl ??? 0 (opp_inverse ??));
 apply (le_rewr ??? x (zero_neutral ??) Px);
 qed.
 
+lemma lt_zero_x_to_lt_opp_x_zero: 
+  ∀G:pogroup.∀x:G.0 < x → -x < 0.
+intros (G x Px); apply (plus_cancr_lt ??? x);
+apply (lt_rewl ??? 0 (opp_inverse ??));
+apply (lt_rewr ??? x (zero_neutral ??) Px);
+qed.
+
 lemma exc_zero_opp_x_to_exc_x_zero: 
-  ∀G:ogroup.∀x:G. 0 ≰ -x → x ≰ 0.
-intros (G x H); apply (exc_canc_plusl ??? (-x));
+  ∀G:pogroup.∀x:G. 0 ≰ -x → x ≰ 0.
+intros (G x H); apply (plus_cancl_exc ??? (-x));
 apply (exc_rewr ???? (plus_comm ???));
 apply (exc_rewl ???? (opp_inverse ??));
 apply (exc_rewr ???? (zero_neutral ??) H);
 qed.
 
 lemma le_x_zero_to_le_zero_opp_x: 
-  ∀G:ogroup.∀x:G. x ≤ 0 → 0 ≤ -x.
+  ∀G:pogroup.∀x:G. x ≤ 0 → 0 ≤ -x.
 intros (G x Lx0); apply (plus_cancr_le ??? x);
 apply (le_rewr ??? 0 (opp_inverse ??));
 apply (le_rewl ??? x (zero_neutral ??));
 assumption; 
 qed.
 
+lemma lt_x_zero_to_lt_zero_opp_x: 
+  ∀G:pogroup.∀x:G. x < 0 → 0 < -x.
+intros (G x Lx0); apply (plus_cancr_lt ??? x);
+apply (lt_rewr ??? 0 (opp_inverse ??));
+apply (lt_rewl ??? x (zero_neutral ??));
+assumption; 
+qed.
+
+
 lemma lt0plus_orlt: 
-  ∀G:ogroup. ∀x,y:G. 0 ≤ x → 0 ≤ y → 0 < x + y → 0 < x ∨ 0 < y.
+  ∀G:pogroup. ∀x,y:G. 0 ≤ x → 0 ≤ y → 0 < x + y → 0 < x ∨ 0 < y.
 intros (G x y LEx LEy LT); cases LT (H1 H2); cases (ap_cotransitive ??? y H2);
 [right; split; assumption|left;split;[assumption]]
 apply (plus_cancr_ap ??? y); apply (ap_rewl ???? (zero_neutral ??));
@@ -163,7 +191,7 @@ assumption;
 qed.
 
 lemma le0plus_le: 
-  ∀G:ogroup.∀a,b,c:G. 0 ≤ b →  a + b ≤ c → a ≤ c.
+  ∀G:pogroup.∀a,b,c:G. 0 ≤ b →  a + b ≤ c → a ≤ c.
 intros (G a b c L H); apply (le_transitive ????? H);
 apply (plus_cancl_le ??? (-a)); 
 apply (le_rewl ??? 0 (opp_inverse ??));
@@ -174,7 +202,7 @@ assumption;
 qed.
 
 lemma le_le0plus: 
-  ∀G:ogroup.∀a,b:G. 0 ≤ a → 0 ≤ b → 0 ≤ a + b.
+  ∀G:pogroup.∀a,b:G. 0 ≤ a → 0 ≤ b → 0 ≤ a + b.
 intros (G a b L1 L2); apply (le_transitive ???? L1);
 apply (plus_cancl_le ??? (-a));
 apply (le_rewl ??? 0 (opp_inverse ??));
@@ -184,5 +212,109 @@ apply (le_rewr ??? b (zero_neutral ??));
 assumption;
 qed.
 
-  
-  
\ No newline at end of file
+lemma flt_plusl: 
+  ∀G:pogroup.∀x,y,z:G.x < y → z + x < z + y.
+intros (G x y z H); cases H; split; [apply fle_plusl; assumption]
+apply fap_plusl; assumption;
+qed.
+
+lemma flt_plusr: 
+  ∀G:pogroup.∀x,y,z:G.x < y → x + z < y + z.
+intros (G x y z H); cases H; split; [apply fle_plusr; assumption]
+apply fap_plusr; assumption;
+qed.
+
+
+lemma ltxy_ltyyxx: ∀G:pogroup.∀x,y:G. y < x → y+y < x+x.
+intros; apply (lt_transitive ?? (y+x));[2: 
+  apply (lt_rewl ???? (plus_comm ???));
+  apply (lt_rewr ???? (plus_comm ???));]
+apply flt_plusl;assumption;
+qed.  
+
+lemma lew_opp : ∀O:pogroup.∀a,b,c:O.0 ≤ b → a ≤ c → a + -b ≤ c.
+intros (O a b c L0 L);
+apply (le_transitive ????? L);
+apply (plus_cancl_le ??? (-a));
+apply (le_rewr ??? 0 (opp_inverse ??));
+apply (le_rewl ??? (-a+a+-b) (plus_assoc ????));
+apply (le_rewl ??? (0+-b) (opp_inverse ??));
+apply (le_rewl ??? (-b) (zero_neutral ?(-b)));
+apply le_zero_x_to_le_opp_x_zero;
+assumption;
+qed.
+
+lemma ltw_opp : ∀O:pogroup.∀a,b,c:O.0 < b → a < c → a + -b < c.
+intros (O a b c P L);
+apply (lt_transitive ????? L);
+apply (plus_cancl_lt ??? (-a));
+apply (lt_rewr ??? 0 (opp_inverse ??));
+apply (lt_rewl ??? (-a+a+-b) (plus_assoc ????));
+apply (lt_rewl ??? (0+-b) (opp_inverse ??));
+apply (lt_rewl ??? ? (zero_neutral ??));
+apply lt_zero_x_to_lt_opp_x_zero;
+assumption;
+qed.
+
+record togroup : Type ≝ {
+  tog_carr:> pogroup;
+  tog_total: ∀x,y:tog_carr.x≰y → y < x
+}.
+
+lemma lexxyy_lexy: ∀G:togroup. ∀x,y:G. x+x ≤ y+y → x ≤ y.
+intros (G x y H); intro H1; lapply (tog_total ??? H1) as H2;
+lapply (ltxy_ltyyxx ??? H2) as H3; lapply (lt_to_excede ??? H3) as H4;
+cases (H H4);
+qed. 
+
+lemma eqxxyy_eqxy: ∀G:togroup.∀x,y:G. x + x ≈ y + y → x ≈ y.
+intros (G x y H); cases (eq_le_le ??? H); apply le_le_eq; 
+apply lexxyy_lexy; assumption;
+qed.
+
+lemma applus_orap: ∀G:abelian_group. ∀x,y:G. 0 # x + y → 0 #x ∨ 0#y.
+intros; cases (ap_cotransitive ??? y a); [right; assumption]
+left; apply (plus_cancr_ap ??? y); apply (ap_rewl ???y (zero_neutral ??));
+assumption;
+qed.
+
+lemma ltplus: ∀G:pogroup.∀a,b,c,d:G. a < b → c < d → a+c < b + d.
+intros (G a b c d H1 H2);
+lapply (flt_plusr ??? c H1) as H3;
+apply (lt_transitive ???? H3);
+apply flt_plusl; assumption;
+qed.
+
+lemma excplus_orexc: ∀G:pogroup.∀a,b,c,d:G. a+c ≰ b + d →  a ≰ b ∨ c ≰ d.
+intros (G a b c d H1 H2);
+cases (exc_cotransitive ??? (a + d) H1); [
+  right; apply (plus_cancl_exc ??? a); assumption]
+left; apply (plus_cancr_exc ??? d); assumption;
+qed.
+
+lemma leplus: ∀G:pogroup.∀a,b,c,d:G. a ≤ b → c ≤ d → a+c ≤ b + d.
+intros (G a b c d H1 H2); intro H3; cases (excplus_orexc ????? H3);
+[apply H1|apply H2] assumption;
+qed.  
+
+lemma leplus_lt_le: ∀G:togroup.∀x,y:G. 0 ≤ x + y → x < 0 → 0 ≤ y.
+intros; intro; apply H; lapply (lt_to_excede ??? l);
+lapply (tog_total ??? e);
+lapply (tog_total ??? Hletin);
+lapply (ltplus ????? Hletin2 Hletin1);
+apply (exc_rewl ??? (0+0)); [apply eq_sym; apply zero_neutral]
+apply lt_to_excede; assumption;
+qed. 
+
+lemma ltplus_orlt: ∀G:togroup.∀a,b,c,d:G. a+c < b + d →  a < b ∨ c < d.
+intros (G a b c d H1 H2); lapply (lt_to_excede ??? H1);
+cases (excplus_orexc ????? Hletin); [left|right] apply tog_total; assumption;
+qed.
+
+lemma excplus: ∀G:togroup.∀a,b,c,d:G.a ≰ b → c ≰ d → a + c ≰ b + d.
+intros (G a b c d L1 L2); 
+lapply (fexc_plusr ??? (c) L1) as L3;
+elim (exc_cotransitive ??? (b+d) L3); [assumption]
+lapply (plus_cancl_exc ???? t); lapply (tog_total ??? Hletin);
+cases Hletin1; cases (H L2);
+qed.