X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fsoftware%2Fmatita%2Fnlibrary%2Fsets%2Fpartitions.ma;h=93f9cd6b5d3e014121adf9ff04042816848cb5a6;hb=8cb2490b5b202549a596cfd1d0f166a5ee43fc4e;hp=93172d6174c206dc3a4abb4012c25e97db32e990;hpb=2c81e4168d6cec784100b0e3cd3f377aa257daee;p=helm.git diff --git a/helm/software/matita/nlibrary/sets/partitions.ma b/helm/software/matita/nlibrary/sets/partitions.ma index 93172d617..93f9cd6b5 100644 --- a/helm/software/matita/nlibrary/sets/partitions.ma +++ b/helm/software/matita/nlibrary/sets/partitions.ma @@ -13,90 +13,184 @@ (**************************************************************************) include "sets/sets.ma". -include "nat/plus.ma". +include "nat/plus.ma". include "nat/compare.ma". include "nat/minus.ma". +include "datatypes/pairs.ma". alias symbol "eq" = "setoid eq". + alias symbol "eq" = "setoid1 eq". alias symbol "eq" = "setoid eq". +alias symbol "eq" = "setoid eq". alias symbol "eq" = "setoid1 eq". +alias symbol "eq" = "setoid eq". nrecord partition (A: setoid) : Type[1] ≝ { support: setoid; indexes: qpowerclass support; class: unary_morphism1 (setoid1_of_setoid support) (qpowerclass_setoid A); inhabited: ∀i. i ∈ indexes → class i ≬ class i; - disjoint: ∀i,j. i ∈ indexes → j ∈ indexes → class i ≬ class j → i=j; - covers: big_union support ? ? (λx.class x) = full_set A - }. napply indexes; nqed. - + disjoint: ∀i,j. i ∈ indexes → j ∈ indexes → class i ≬ class j → i = j; + covers: big_union support ? indexes (λx.class x) = full_set A + }. + naxiom daemon: False. -nlet rec partition_splits_card_map - A (P:partition A) n s (f:isomorphism ?? (Nat_ n) (indexes ? P)) - (fi: ∀i. isomorphism ?? (Nat_ (s i)) (class ? P (iso_f ???? f i))) m index - on index : A ≝ +nlet rec iso_nat_nat_union (s: nat → nat) m index on index : pair nat nat ≝ match ltb m (s index) with - [ or_introl _ ⇒ iso_f ???? (fi index) m - | or_intror _ ⇒ + [ true ⇒ mk_pair … index m + | false ⇒ match index with - [ O ⇒ (* dummy value: it could be an elim False: *) iso_f ???? (fi O) O - | S index' ⇒ - partition_splits_card_map A P n s f fi (minus m (s index)) index']]. + [ O ⇒ (* dummy value: it could be an elim False: *) mk_pair … O O + | S index' ⇒ iso_nat_nat_union s (minus m (s index)) index']]. -naxiom big_union_preserves_iso: - ∀A,A',B,T,T',f. - ∀g: isomorphism A' A T' T. - big_union A B T f = big_union A' B T' (λx.f (iso_f ???? g x)). +alias symbol "eq" = "leibnitz's equality". +naxiom plus_n_O: ∀n. n + O = n. +naxiom plus_n_S: ∀n,m. n + S m = S (n + m). +naxiom ltb_t: ∀n,m. n < m → ltb n m = true. +naxiom ltb_f: ∀n,m. ¬ (n < m) → ltb n m = false. +naxiom ltb_cases: ∀n,m. (n < m ∧ ltb n m = true) ∨ (¬ (n < m) ∧ ltb n m = false). +naxiom minus_canc: ∀n. minus n n = O. +naxiom ad_hoc9: ∀a,b,c. a < b + c → a - b < c. +naxiom ad_hoc10: ∀a,b,c. a - b = c → a = b + c. +naxiom ad_hoc11: ∀a,b. a - b ≤ S a - b. +naxiom ad_hoc12: ∀a,b. b ≤ a → S a - b - (a - b) = S O. +naxiom ad_hoc13: ∀a,b. b ≤ a → (O + (a - b)) + b = a. +naxiom ad_hoc14: ∀a,b,c,d,e. c ≤ a → a - c = b + d + e → a = b + (c + d) + e. +naxiom ad_hoc15: ∀a,a',b,c. a=a' → b < c → a + b < c + a'. +naxiom ad_hoc16: ∀a,b,c. a < c → a < b + c. +naxiom not_lt_to_le: ∀a,b. ¬ (a < b) → b ≤ a. +naxiom le_to_le_S_S: ∀a,b. a ≤ b → S a ≤ S b. +naxiom minus_S: ∀n. S n - n = S O. +naxiom ad_hoc17: ∀a,b,c,d,d'. a+c+d=b+c+d' → a+d=b+d'. +naxiom split_big_plus: + ∀n,m,f. m ≤ n → + big_plus n f = big_plus m (λi,p.f i ?) + big_plus (n - m) (λi.λp.f (i + m) ?). + nelim daemon. +nqed. +naxiom big_plus_preserves_ext: + ∀n,f,f'. (∀i,p. f i p = f' i p) → big_plus n f = big_plus n f'. + +ntheorem iso_nat_nat_union_char: + ∀n:nat. ∀s: nat → nat. ∀m:nat. m < big_plus (S n) (λi.λ_.s i) → + let p ≝ iso_nat_nat_union s m n in + m = big_plus (n - fst … p) (λi.λ_.s (S (i + fst … p))) + snd … p ∧ + fst … p ≤ n ∧ snd … p < s (fst … p). + #n; #s; nelim n + [ #m; nwhd in ⊢ (??% → let p ≝ % in ?); nwhd in ⊢ (??(??%) → ?); + nrewrite > (plus_n_O (s O)); #H; nrewrite > (ltb_t … H); nnormalize; @ + [ @ [ napply refl | napply le_n ] ##| nassumption ] +##| #n'; #Hrec; #m; nwhd in ⊢ (??% → let p ≝ % in ?); #H; + ncases (ltb_cases m (s (S n'))); *; #H1; #H2; nrewrite > H2; + nwhd in ⊢ (let p ≝ % in ?); nwhd + [ napply conj [napply conj + [ nwhd in ⊢ (????(?(?%(λ_.λ_:(??%).?))%)); nrewrite > (minus_canc n'); napply refl + | nnormalize; napply le_n] + ##| nnormalize; nassumption ] + ##| nchange in H with (m < s (S n') + big_plus (S n') (λi.λ_.s i)); + nlapply (Hrec (m - s (S n')) ?) + [ napply ad_hoc9; nassumption] *; *; #Hrec1; #Hrec2; #Hrec3; @ + [##2: nassumption + |@ + [nrewrite > (split_big_plus …); ##[##2:napply ad_hoc11;##|##3:##skip] + nrewrite > (ad_hoc12 …); ##[##2: nassumption] + nwhd in ⊢ (????(?(??%)?)); + nrewrite > (ad_hoc13 …);##[##2: nassumption] + napply ad_hoc14 [ napply not_lt_to_le; nassumption ] + nwhd in ⊢ (???(?(??%)?)); + nrewrite > (plus_n_O …); + nassumption; + ##| napply le_S; nassumption ]##]##]##] +nqed. + +ntheorem iso_nat_nat_union_pre: + ∀n:nat. ∀s: nat → nat. + ∀i1,i2. i1 ≤ n → i2 < s i1 → + big_plus (n - i1) (λi.λ_.s (S (i + i1))) + i2 < big_plus (S n) (λi.λ_.s i). + #n; #s; #i1; #i2; #H1; #H2; + nrewrite > (split_big_plus (S n) (S i1) (λi.λ_.s i) ?) + [##2: napply le_to_le_S_S; nassumption] + napply ad_hoc15 + [ nwhd in ⊢ (???(?%?)); + napply big_plus_preserves_ext; #i; #_; + nrewrite > (plus_n_S i i1); napply refl + | nrewrite > (split_big_plus (S i1) i1 (λi.λ_.s i) ?) [##2: napply le_S; napply le_n] + napply ad_hoc16; nrewrite > (minus_S i1); nnormalize; nrewrite > (plus_n_O (s i1) …); + nassumption ] +nqed. + +ntheorem iso_nat_nat_union_uniq: + ∀n:nat. ∀s: nat → nat. + ∀i1,i1',i2,i2'. i1 ≤ n → i1' ≤ n → i2 < s i1 → i2' < s i1' → + big_plus (n - i1) (λi.λ_.s (S (i + i1))) + i2 = big_plus (n - i1') (λi.λ_.s (S (i + i1'))) + i2' → + i1 = i1' ∧ i2 = i2'. + #n; #s; #i1; #i1'; #i2; #i2'; #H1; #H1'; #H2; #H2'; #E; + nelim daemon. +nqed. nlemma partition_splits_card: ∀A. ∀P:partition A. ∀n,s. ∀f:isomorphism ?? (Nat_ n) (indexes ? P). (∀i. isomorphism ?? (Nat_ (s i)) (class ? P (iso_f ???? f i))) → (isomorphism ?? (Nat_ (big_plus n (λi.λ_.s i))) (Full_set A)). - #A; #P; #Sn; ncases Sn +#A; #P; #Sn; ncases Sn [ #s; #f; #fi; - ngeneralize in match (covers ? P) in ⊢ ?; *; #_; #H; - ngeneralize in match - (big_union_preserves_iso ??? (indexes A P) (Nat_ O) (λx.class ? P x) f) in ⊢ ?; - *; #K; #_; nwhd in K: (? → ? → %); + nlapply (covers ? P); *; #_; #H; + (* + nlapply + (big_union_preserves_iso ??? (indexes A P) (Nat_ O) (λx.class ? P x) f); + *; #K; #_; nwhd in K: (? → ? → %);*) nelim daemon (* impossibile *) - | #n; #s; #f; #fi; napply mk_isomorphism - [ napply mk_unary_morphism - [ napply (λm.partition_splits_card_map A P (S n) s f fi m n) + | #n; #s; #f; #fi; @ + [ @ + [ napply (λm.let p ≝ (iso_nat_nat_union s m n) in iso_f ???? (fi (fst … p)) (snd … p)) | #a; #a'; #H; nrewrite < H; napply refl ] +##| #x; #Hx; nwhd; napply I ##| #y; #_; - ngeneralize in match (covers ? P) in ⊢ ?; *; #_; #Hc; - ngeneralize in match (Hc y I) in ⊢ ?; *; #index; *; #Hi1; #Hi2; - ngeneralize in match (f_sur ???? f ? Hi1) in ⊢ ?; *; #nindex; *; #Hni1; #Hni2; - ngeneralize in match (f_sur ???? (fi nindex) y ?) in ⊢ ? - [##2: napply (. #‡(†?));##[##3: napply Hni2 |##2: ##skip | nassumption]##] + nlapply (covers ? P); *; #_; #Hc; + nlapply (Hc y I); *; #index; *; #Hi1; #Hi2; + nlapply (f_sur ???? f ? Hi1); *; #nindex; *; #Hni1; #Hni2; + nlapply (f_sur ???? (fi nindex) y ?) + [ alias symbol "refl" = "refl". +alias symbol "prop1" = "prop11". +napply (. #‡(†?));##[##2: napply Hni2 |##1: ##skip | nassumption]##] *; #nindex2; *; #Hni21; #Hni22; - nletin xxx ≝ (plus match nindex return λ_.nat with [ O ⇒ O | S nn ⇒ big_plus nn (λi.λ_.s i)] nindex2); - napply (ex_intro … xxx); napply conj - [ nwhd in Hni1; nelim daemon - | nwhd in ⊢ (???%?); - (* BEL POSTO DOVE FARE UN LEMMA *) - (* invariante: Hni1; altre premesse: Hni1, Hni22 *) - nchange in Hni1 with (nindex < S n); ngeneralize in match Hni1 in ⊢ ?; - nelim n in ⊢ (% → ??? (????????%) ?) - [ #A (* decompose *) - | #index'; #Hrec; #K; nwhd in ⊢ (???%?); - nelim (ltb xxx (s (S index'))); - #K1; nwhd in ⊢ (???%?) - [ - - nindex < S index' + 1 - +^{nindex} (s i) w < s (S index') - S index' == nindex - - | - ] - ] - ] - | #x; #x'; nnormalize in ⊢ (? → ? → %); - nelim daemon - ] + nletin xxx ≝ (plus (big_plus (minus n nindex) (λi.λ_.s (S (plus i nindex)))) nindex2); + @ xxx; @ + [ napply iso_nat_nat_union_pre [ napply le_S_S_to_le; nassumption | nassumption ] + ##| nwhd in ⊢ (???%%); napply (.= ?) [##3: nassumption|##skip] + nlapply (iso_nat_nat_union_char n s xxx ?) + [napply iso_nat_nat_union_pre [ napply le_S_S_to_le; nassumption | nassumption]##] + *; *; #K1; #K2; #K3; + nlapply + (iso_nat_nat_union_uniq n s nindex (fst … (iso_nat_nat_union s xxx n)) + nindex2 (snd … (iso_nat_nat_union s xxx n)) ?????) + [##2: *; #E1; #E2; nrewrite > E1; nrewrite > E2; napply refl + | napply le_S_S_to_le; nassumption + |##*: nassumption]##] +##| #x; #x'; nnormalize in ⊢ (? → ? → %); #Hx; #Hx'; #E; + ngeneralize in match (? : ∀i1,i2,i1',i2'. i1 ∈ Nat_ (S n) → i1' ∈ Nat_ (S n) → i2 ∈ pc ? (Nat_ (s i1)) → i2' ∈ pc ? (Nat_ (s i1')) → eq_rel (carr A) (eq A) (iso_f ???? (fi i1) i2) (iso_f ???? (fi i1') i2') → i1=i1' ∧ i2=i2') in ⊢ ? + [##2: #i1; #i2; #i1'; #i2'; #Hi1; #Hi1'; #Hi2; #Hi2'; #E; + ngeneralize in match (disjoint ? P (iso_f ???? f i1) (iso_f ???? f i1') ???) in ⊢ ? + [##2,3: napply f_closed; nassumption + |##4: napply ex_intro [ napply (iso_f ???? (fi i1) i2) ] napply conj + [ napply f_closed; nassumption ##| napply (. ?‡#) [ nassumption | ##2: ##skip] + nwhd; napply f_closed; nassumption]##] + #E'; ngeneralize in match (? : i1=i1') in ⊢ ? + [##2: napply (f_inj … E'); nassumption + | #E''; nrewrite < E''; napply conj + [ napply refl | nrewrite < E'' in E; #E'''; napply (f_inj … E''') + [ nassumption | nrewrite > E''; nassumption ]##]##] + ##] #K; + nelim (iso_nat_nat_union_char n s x Hx); *; #i1x; #i2x; #i3x; + nelim (iso_nat_nat_union_char n s x' Hx'); *; #i1x'; #i2x'; #i3x'; + ngeneralize in match (K … E) in ⊢ ? + [##2,3: napply le_to_le_S_S; nassumption + |##4,5: nassumption] + *; #K1; #K2; + napply (eq_rect_CProp0_r ?? (λX.λ_.? = X) ?? i1x'); + napply (eq_rect_CProp0_r ?? (λX.λ_.X = ?) ?? i1x); + nrewrite > K1; nrewrite > K2; napply refl ] nqed. (************** equivalence relations vs partitions **********************) @@ -106,12 +200,14 @@ ndefinition partition_of_compatible_equivalence_relation: #A; #R; napply mk_partition [ napply (quotient ? R) | napply Full_set - | #a; napply mk_qpowerclass - [ napply {x | R x a} - | #x; #x'; #H; nnormalize; napply mk_iff; #K; nelim daemon] + | napply mk_unary_morphism1 + [ #a; napply mk_qpowerclass + [ napply {x | R x a} + | #x; #x'; #H; nnormalize; napply mk_iff; #K; nelim daemon] + ##| #a; #a'; #H; napply conj; #x; nnormalize; #K [ nelim daemon | nelim daemon]##] ##| #x; #_; nnormalize; napply (ex_intro … x); napply conj; napply refl | #x; #x'; #_; #_; nnormalize; *; #x''; *; #H1; #H2; napply (trans ?????? H2); napply sym; nassumption | nnormalize; napply conj [ #a; #_; napply I | #a; #_; napply (ex_intro … a); napply conj [ napply I | napply refl]##] -nqed. \ No newline at end of file +nqed.