Category of partial orders #
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This defines PartOrd
, the category of partial orders with monotone maps.
The category of partially ordered types.
Equations
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Equations
- PartOrd.partial_order.to_preorder.category_theory.bundled_hom.parent_projection = category_theory.bundled_hom.parent_projection.mk
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Construct a bundled PartOrd from the underlying type and typeclass.
Equations
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Equations
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Equations
- α.partial_order = α.str
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Constructs an equivalence between partial orders from an order isomorphism between them.
Equations
- PartOrd.iso.mk e = {hom := ↑e, inv := ↑(e.symm), hom_inv_id' := _, inv_hom_id' := _}
order_dual
as a functor.
Equations
- PartOrd.dual = {obj := λ (X : PartOrd), PartOrd.of (↥X)ᵒᵈ, map := λ (X Y : PartOrd), ⇑order_hom.dual, map_id' := PartOrd.dual._proof_1, map_comp' := PartOrd.dual._proof_2}
@[simp]
The equivalence between PartOrd
and itself induced by order_dual
both ways.
Equations
- PartOrd.dual_equiv = category_theory.equivalence.mk PartOrd.dual PartOrd.dual (category_theory.nat_iso.of_components (λ (X : PartOrd), PartOrd.iso.mk (order_iso.dual_dual ↥X)) PartOrd.dual_equiv._proof_1) (category_theory.nat_iso.of_components (λ (X : PartOrd), PartOrd.iso.mk (order_iso.dual_dual ↥X)) PartOrd.dual_equiv._proof_2)
antisymmetrization
as a functor. It is the free functor.
Equations
- Preord_to_PartOrd = {obj := λ (X : Preord), PartOrd.of (antisymmetrization ↥X has_le.le), map := λ (X Y : Preord) (f : X ⟶ Y), order_hom.antisymmetrization f, map_id' := Preord_to_PartOrd._proof_2, map_comp' := Preord_to_PartOrd._proof_3}
Preord_to_PartOrd
is left adjoint to the forgetful functor, meaning it is the free
functor from Preord
to PartOrd
.
Equations
- Preord_to_PartOrd_forget_adjunction = category_theory.adjunction.mk_of_hom_equiv {hom_equiv := λ (X : Preord) (Y : PartOrd), {to_fun := λ (f : Preord_to_PartOrd.obj X ⟶ Y), {to_fun := ⇑f ∘ to_antisymmetrization has_le.le, monotone' := _}, inv_fun := λ (f : X ⟶ (category_theory.forget₂ PartOrd Preord).obj Y), {to_fun := λ (a : ↥(Preord_to_PartOrd.obj X)), quotient.lift_on' a ⇑f _, monotone' := _}, left_inv := _, right_inv := _}, hom_equiv_naturality_left_symm' := Preord_to_PartOrd_forget_adjunction._proof_6, hom_equiv_naturality_right' := Preord_to_PartOrd_forget_adjunction._proof_7}
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Preord_to_PartOrd
and order_dual
commute.
Equations
- Preord_to_PartOrd_comp_to_dual_iso_to_dual_comp_Preord_to_PartOrd = category_theory.nat_iso.of_components (λ (X : Preord), PartOrd.iso.mk (order_iso.dual_antisymmetrization ↥X)) Preord_to_PartOrd_comp_to_dual_iso_to_dual_comp_Preord_to_PartOrd._proof_1
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