Mercurial > hg > Members > kono > Proof > category
view cat-utility.agda @ 456:4d97955ea419
limit with nat
| author | Shinji KONO <kono@ie.u-ryukyu.ac.jp> |
|---|---|
| date | Thu, 02 Mar 2017 17:41:20 +0900 |
| parents | f526f4b68565 |
| children | 961c236807f1 |
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module cat-utility where -- Shinji KONO <kono@ie.u-ryukyu.ac.jp> open import Category -- https://github.com/konn/category-agda open import Level --open import Category.HomReasoning open import HomReasoning open Functor id1 : ∀{c₁ c₂ ℓ : Level} (A : Category c₁ c₂ ℓ) (a : Obj A ) → Hom A a a id1 A a = (Id {_} {_} {_} {A} a) -- We cannot make A implicit record IsUniversalMapping {c₁ c₂ ℓ c₁' c₂' ℓ' : Level} (A : Category c₁ c₂ ℓ) (B : Category c₁' c₂' ℓ') ( U : Functor B A ) ( F : Obj A → Obj B ) ( η : (a : Obj A) → Hom A a ( FObj U (F a) ) ) ( _* : { a : Obj A}{ b : Obj B} → ( Hom A a (FObj U b) ) → Hom B (F a ) b ) : Set (suc (c₁ ⊔ c₂ ⊔ ℓ ⊔ c₁' ⊔ c₂' ⊔ ℓ' )) where field universalMapping : {a : Obj A} { b : Obj B } → { f : Hom A a (FObj U b) } → A [ A [ FMap U ( f * ) o η a ] ≈ f ] uniquness : {a : Obj A} { b : Obj B } → { f : Hom A a (FObj U b) } → { g : Hom B (F a) b } → A [ A [ FMap U g o η a ] ≈ f ] → B [ f * ≈ g ] record UniversalMapping {c₁ c₂ ℓ c₁' c₂' ℓ' : Level} (A : Category c₁ c₂ ℓ) (B : Category c₁' c₂' ℓ') ( U : Functor B A ) ( F : Obj A → Obj B ) ( η : (a : Obj A) → Hom A a ( FObj U (F a) ) ) : Set (suc (c₁ ⊔ c₂ ⊔ ℓ ⊔ c₁' ⊔ c₂' ⊔ ℓ' )) where infixr 11 _* field _* : { a : Obj A}{ b : Obj B} → ( Hom A a (FObj U b) ) → Hom B (F a ) b isUniversalMapping : IsUniversalMapping A B U F η _* record coIsUniversalMapping {c₁ c₂ ℓ c₁' c₂' ℓ' : Level} (A : Category c₁ c₂ ℓ) (B : Category c₁' c₂' ℓ') ( F : Functor A B ) ( U : Obj B → Obj A ) ( ε : (b : Obj B) → Hom B ( FObj F (U b) ) b ) ( _*' : { b : Obj B}{ a : Obj A} → ( Hom B (FObj F a) b ) → Hom A a (U b ) ) : Set (suc (c₁ ⊔ c₂ ⊔ ℓ ⊔ c₁' ⊔ c₂' ⊔ ℓ' )) where field couniversalMapping : {b : Obj B} { a : Obj A } → { f : Hom B (FObj F a) b } → B [ B [ ε b o FMap F ( f *' ) ] ≈ f ] couniquness : {b : Obj B} { a : Obj A } → { f : Hom B (FObj F a) b } → { g : Hom A a (U b) } → B [ B [ ε b o FMap F g ] ≈ f ] → A [ f *' ≈ g ] record coUniversalMapping {c₁ c₂ ℓ c₁' c₂' ℓ' : Level} (A : Category c₁ c₂ ℓ) (B : Category c₁' c₂' ℓ') ( F : Functor A B ) ( U : Obj B → Obj A ) ( ε : (b : Obj B) → Hom B ( FObj F (U b) ) b ) : Set (suc (c₁ ⊔ c₂ ⊔ ℓ ⊔ c₁' ⊔ c₂' ⊔ ℓ' )) where infixr 11 _*' field _*' : { b : Obj B}{ a : Obj A} → ( Hom B (FObj F a) b ) → Hom A a (U b ) iscoUniversalMapping : coIsUniversalMapping A B F U ε _*' open NTrans open import Category.Cat record IsAdjunction {c₁ c₂ ℓ c₁' c₂' ℓ' : Level} (A : Category c₁ c₂ ℓ) (B : Category c₁' c₂' ℓ') ( U : Functor B A ) ( F : Functor A B ) ( η : NTrans A A identityFunctor ( U ○ F ) ) ( ε : NTrans B B ( F ○ U ) identityFunctor ) : Set (suc (c₁ ⊔ c₂ ⊔ ℓ ⊔ c₁' ⊔ c₂' ⊔ ℓ' )) where field adjoint1 : { b : Obj B } → A [ A [ ( FMap U ( TMap ε b )) o ( TMap η ( FObj U b )) ] ≈ id1 A (FObj U b) ] adjoint2 : {a : Obj A} → B [ B [ ( TMap ε ( FObj F a )) o ( FMap F ( TMap η a )) ] ≈ id1 B (FObj F a) ] record Adjunction {c₁ c₂ ℓ c₁' c₂' ℓ' : Level} (A : Category c₁ c₂ ℓ) (B : Category c₁' c₂' ℓ') ( U : Functor B A ) ( F : Functor A B ) ( η : NTrans A A identityFunctor ( U ○ F ) ) ( ε : NTrans B B ( F ○ U ) identityFunctor ) : Set (suc (c₁ ⊔ c₂ ⊔ ℓ ⊔ c₁' ⊔ c₂' ⊔ ℓ' )) where field isAdjunction : IsAdjunction A B U F η ε U-functor = U F-functor = F Eta = η Epsiron = ε record IsMonad {c₁ c₂ ℓ : Level} (A : Category c₁ c₂ ℓ) ( T : Functor A A ) ( η : NTrans A A identityFunctor T ) ( μ : NTrans A A (T ○ T) T) : Set (suc (c₁ ⊔ c₂ ⊔ ℓ )) where field assoc : {a : Obj A} → A [ A [ TMap μ a o TMap μ ( FObj T a ) ] ≈ A [ TMap μ a o FMap T (TMap μ a) ] ] unity1 : {a : Obj A} → A [ A [ TMap μ a o TMap η ( FObj T a ) ] ≈ Id {_} {_} {_} {A} (FObj T a) ] unity2 : {a : Obj A} → A [ A [ TMap μ a o (FMap T (TMap η a ))] ≈ Id {_} {_} {_} {A} (FObj T a) ] record Monad {c₁ c₂ ℓ : Level} (A : Category c₁ c₂ ℓ) (T : Functor A A) (η : NTrans A A identityFunctor T) (μ : NTrans A A (T ○ T) T) : Set (suc (c₁ ⊔ c₂ ⊔ ℓ )) where field isMonad : IsMonad A T η μ -- g ○ f = μ(c) T(g) f join : { a b : Obj A } → { c : Obj A } → ( Hom A b ( FObj T c )) → ( Hom A a ( FObj T b)) → Hom A a ( FObj T c ) join {_} {_} {c} g f = A [ TMap μ c o A [ FMap T g o f ] ] Functor*Nat : {c₁ c₂ ℓ c₁' c₂' ℓ' c₁'' c₂'' ℓ'' : Level} (A : Category c₁ c₂ ℓ) {B : Category c₁' c₂' ℓ'} (C : Category c₁'' c₂'' ℓ'') (F : Functor B C) → { G H : Functor A B } → ( n : NTrans A B G H ) → NTrans A C (F ○ G) (F ○ H) Functor*Nat A {B} C F {G} {H} n = record { TMap = λ a → FMap F (TMap n a) ; isNTrans = record { commute = commute } } where commute : {a b : Obj A} {f : Hom A a b} → C [ C [ (FMap F ( FMap H f )) o ( FMap F (TMap n a)) ] ≈ C [ (FMap F (TMap n b )) o (FMap F (FMap G f)) ] ] commute {a} {b} {f} = let open ≈-Reasoning (C) in begin (FMap F ( FMap H f )) o ( FMap F (TMap n a)) ≈⟨ sym (distr F) ⟩ FMap F ( B [ (FMap H f) o TMap n a ]) ≈⟨ IsFunctor.≈-cong (isFunctor F) ( nat n ) ⟩ FMap F ( B [ (TMap n b ) o FMap G f ] ) ≈⟨ distr F ⟩ (FMap F (TMap n b )) o (FMap F (FMap G f)) ∎ Nat*Functor : {c₁ c₂ ℓ c₁' c₂' ℓ' c₁'' c₂'' ℓ'' : Level} (A : Category c₁ c₂ ℓ) {B : Category c₁' c₂' ℓ'} (C : Category c₁'' c₂'' ℓ'') { G H : Functor B C } → ( n : NTrans B C G H ) → (F : Functor A B) → NTrans A C (G ○ F) (H ○ F) Nat*Functor A {B} C {G} {H} n F = record { TMap = λ a → TMap n (FObj F a) ; isNTrans = record { commute = commute } } where commute : {a b : Obj A} {f : Hom A a b} → C [ C [ ( FMap H (FMap F f )) o ( TMap n (FObj F a)) ] ≈ C [ (TMap n (FObj F b )) o (FMap G (FMap F f)) ] ] commute {a} {b} {f} = IsNTrans.commute ( isNTrans n) -- T ≃ (U_R ○ F_R) -- μ = U_R ε F_R -- nat-ε -- nat-η -- same as η but has different types record MResolution {c₁ c₂ ℓ c₁' c₂' ℓ' : Level} (A : Category c₁ c₂ ℓ) ( B : Category c₁' c₂' ℓ' ) ( T : Functor A A ) -- { η : NTrans A A identityFunctor T } -- { μ : NTrans A A (T ○ T) T } -- { M : Monad A T η μ } ( UR : Functor B A ) ( FR : Functor A B ) { ηR : NTrans A A identityFunctor ( UR ○ FR ) } { εR : NTrans B B ( FR ○ UR ) identityFunctor } { μR : NTrans A A ( (UR ○ FR) ○ ( UR ○ FR )) ( UR ○ FR ) } ( Adj : Adjunction A B UR FR ηR εR ) : Set (suc (c₁ ⊔ c₂ ⊔ ℓ ⊔ c₁' ⊔ c₂' ⊔ ℓ' )) where field T=UF : T ≃ (UR ○ FR) μ=UεF : {x : Obj A } → A [ TMap μR x ≈ FMap UR ( TMap εR ( FObj FR x ) ) ] -- ηR=η : {x : Obj A } → A [ TMap ηR x ≈ TMap η x ] -- We need T → UR FR conversion -- μR=μ : {x : Obj A } → A [ TMap μR x ≈ TMap μ x ] -- -- e f -- c -------→ a ---------→ b -- ^ . ---------→ -- | . g -- |k . -- | . h -- d record IsEqualizer { c₁ c₂ ℓ : Level} ( A : Category c₁ c₂ ℓ ) {c a b : Obj A} (e : Hom A c a) (f g : Hom A a b) : Set (ℓ ⊔ (c₁ ⊔ c₂)) where field fe=ge : A [ A [ f o e ] ≈ A [ g o e ] ] k : {d : Obj A} (h : Hom A d a) → A [ A [ f o h ] ≈ A [ g o h ] ] → Hom A d c ek=h : {d : Obj A} → ∀ {h : Hom A d a} → {eq : A [ A [ f o h ] ≈ A [ g o h ] ] } → A [ A [ e o k {d} h eq ] ≈ h ] uniqueness : {d : Obj A} → ∀ {h : Hom A d a} → {eq : A [ A [ f o h ] ≈ A [ g o h ] ] } → {k' : Hom A d c } → A [ A [ e o k' ] ≈ h ] → A [ k {d} h eq ≈ k' ] equalizer1 : Hom A c a equalizer1 = e record Equalizer { c₁ c₂ ℓ : Level} ( A : Category c₁ c₂ ℓ ) {a b : Obj A} (f g : Hom A a b) : Set (ℓ ⊔ (c₁ ⊔ c₂)) where field equalizer-c : Obj A equalizer : Hom A equalizer-c a isEqualizer : IsEqualizer A equalizer f g -- -- Product -- -- c -- f | g -- |f×g -- v -- a <-------- ab ---------→ b -- π1 π2 record Product { c₁ c₂ ℓ : Level} ( A : Category c₁ c₂ ℓ ) (a b ab : Obj A) ( π1 : Hom A ab a ) ( π2 : Hom A ab b ) : Set (ℓ ⊔ (c₁ ⊔ c₂)) where field _×_ : {c : Obj A} ( f : Hom A c a ) → ( g : Hom A c b ) → Hom A c ab π1fxg=f : {c : Obj A} { f : Hom A c a } → { g : Hom A c b } → A [ A [ π1 o ( f × g ) ] ≈ f ] π2fxg=g : {c : Obj A} { f : Hom A c a } → { g : Hom A c b } → A [ A [ π2 o ( f × g ) ] ≈ g ] uniqueness : {c : Obj A} { h : Hom A c ab } → A [ ( A [ π1 o h ] ) × ( A [ π2 o h ] ) ≈ h ] ×-cong : {c : Obj A} { f f' : Hom A c a } → { g g' : Hom A c b } → A [ f ≈ f' ] → A [ g ≈ g' ] → A [ f × g ≈ f' × g' ] record CreateProduct { c₁ c₂ ℓ : Level} ( A : Category c₁ c₂ ℓ ) : Set (ℓ ⊔ (c₁ ⊔ c₂)) where field product : (a b : Obj A) -> Obj A π1 : (a b : Obj A) -> Hom A (product a b ) a π2 : (a b : Obj A) -> Hom A (product a b ) b isProduct : (a b : Obj A) -> Product A a b (product a b) (π1 a b ) (π2 a b) -- Pullback -- f -- a ------→ c -- ^ ^ -- π1 | |g -- | | -- ab ------→ b -- ^ π2 -- | -- d -- record Pullback { c₁ c₂ ℓ : Level} ( A : Category c₁ c₂ ℓ ) (a b c ab : Obj A) ( f : Hom A a c ) ( g : Hom A b c ) ( π1 : Hom A ab a ) ( π2 : Hom A ab b ) : Set (ℓ ⊔ (c₁ ⊔ c₂)) where field commute : A [ A [ f o π1 ] ≈ A [ g o π2 ] ] p : { d : Obj A } → { π1' : Hom A d a } { π2' : Hom A d b } → A [ A [ f o π1' ] ≈ A [ g o π2' ] ] → Hom A d ab π1p=π1 : { d : Obj A } → { π1' : Hom A d a } { π2' : Hom A d b } → { eq : A [ A [ f o π1' ] ≈ A [ g o π2' ] ] } → A [ A [ π1 o p eq ] ≈ π1' ] π2p=π2 : { d : Obj A } → { π1' : Hom A d a } { π2' : Hom A d b } → { eq : A [ A [ f o π1' ] ≈ A [ g o π2' ] ] } → A [ A [ π2 o p eq ] ≈ π2' ] uniqueness : { d : Obj A } → ( p' : Hom A d ab ) → { π1' : Hom A d a } { π2' : Hom A d b } → { eq : A [ A [ f o π1' ] ≈ A [ g o π2' ] ] } → { π1p=π1' : A [ A [ π1 o p' ] ≈ π1' ] } → { π2p=π2' : A [ A [ π2 o p' ] ≈ π2' ] } → A [ p eq ≈ p' ] axb : Obj A axb = ab pi1 : Hom A ab a pi1 = π1 pi2 : Hom A ab b pi2 = π2 -- -- Limit -- ----- -- Constancy Functor K : { c₁' c₂' ℓ' : Level} (A : Category c₁' c₂' ℓ') { c₁'' c₂'' ℓ'' : Level} ( I : Category c₁'' c₂'' ℓ'' ) → ( a : Obj A ) → Functor I A K A I a = record { FObj = λ i → a ; FMap = λ f → id1 A a ; isFunctor = let open ≈-Reasoning (A) in record { ≈-cong = λ f=g → refl-hom ; identity = refl-hom ; distr = sym idL } } record Limit { c₁' c₂' ℓ' : Level} { c₁ c₂ ℓ : Level} ( A : Category c₁ c₂ ℓ ) ( I : Category c₁' c₂' ℓ' ) ( Γ : Functor I A ) ( a0 : Obj A ) ( t0 : NTrans I A ( K A I a0 ) Γ ) : Set (suc (c₁' ⊔ c₂' ⊔ ℓ' ⊔ c₁ ⊔ c₂ ⊔ ℓ )) where field limit : ( a : Obj A ) → ( t : NTrans I A ( K A I a ) Γ ) → Hom A a a0 t0f=t : { a : Obj A } → { t : NTrans I A ( K A I a ) Γ } → ∀ { i : Obj I } → A [ A [ TMap t0 i o limit a t ] ≈ TMap t i ] limit-uniqueness : { a : Obj A } → { t : NTrans I A ( K A I a ) Γ } → ( f : Hom A a a0 ) → ( ∀ { i : Obj I } → A [ A [ TMap t0 i o f ] ≈ TMap t i ] ) → A [ limit a t ≈ f ] A0 : Obj A A0 = a0 T0 : NTrans I A ( K A I a0 ) Γ T0 = t0 record CreateLimit { c₁' c₂' ℓ' : Level} { c₁ c₂ ℓ : Level} ( A : Category c₁ c₂ ℓ ) ( I : Category c₁' c₂' ℓ' ) : Set (suc (c₁' ⊔ c₂' ⊔ ℓ' ⊔ c₁ ⊔ c₂ ⊔ ℓ )) where field limit-c : ( Γ : Functor I A ) -> Obj A isLimit : ( Γ : Functor I A ) -> (limit-u : NTrans I A ( K A I (limit-c Γ) ) Γ ) -> Limit A I Γ (limit-c Γ) limit-u record Complete { c₁' c₂' ℓ' : Level} { c₁ c₂ ℓ : Level} ( A : Category c₁ c₂ ℓ ) ( I : Category c₁' c₂' ℓ' ) : Set (suc (c₁' ⊔ c₂' ⊔ ℓ' ⊔ c₁ ⊔ c₂ ⊔ ℓ )) where field limit-c : ( Γ : Functor I A ) -> Obj A isLimit : ( Γ : Functor I A ) -> (limit-u : NTrans I A ( K A I (limit-c Γ) ) Γ) -> Limit A I Γ (limit-c Γ) limit-u product : (a b : Obj A) -> Obj A π1 : (a b : Obj A) -> Hom A (product a b ) a π2 : (a b : Obj A) -> Hom A (product a b ) b isProduct : (a b : Obj A) -> Product A a b (product a b) (π1 a b ) (π2 a b) equalizer-p : {a b : Obj A} (f g : Hom A a b) -> Obj A equalizer-e : {a b : Obj A} (f g : Hom A a b) -> Hom A (equalizer-p f g) a isEqualizer : {a b : Obj A} (f g : Hom A a b) -> IsEqualizer A (equalizer-e f g) f g