Lattice homomorphisms #
This file defines (bounded) lattice homomorphisms.
We use the DFunLike
design, so each type of morphisms has a companion typeclass which is meant to
be satisfied by itself and all stricter types.
Types of morphisms #
SupHom
: Maps which preserve⊔
.InfHom
: Maps which preserve⊓
.SupBotHom
: Finitary supremum homomorphisms. Maps which preserve⊔
and⊥
.InfTopHom
: Finitary infimum homomorphisms. Maps which preserve⊓
and⊤
.LatticeHom
: Lattice homomorphisms. Maps which preserve⊔
and⊓
.BoundedLatticeHom
: Bounded lattice homomorphisms. Maps which preserve⊤
,⊥
,⊔
and⊓
.
Typeclasses #
TODO #
Do we need more intersections between BotHom
, TopHom
and lattice homomorphisms?
The type of lattice homomorphisms from α
to β
.
- toFun : α → β
A
LatticeHom
preserves infima.
Instances For
The type of bounded lattice homomorphisms from α
to β
.
- toFun : α → β
A
BoundedLatticeHom
preserves the top element.A
BoundedLatticeHom
preserves the bottom element.
Instances For
SupHomClass F α β
states that F
is a type of ⊔
-preserving morphisms.
You should extend this class when you extend SupHom
.
A
SupHomClass
morphism preserves suprema.
Instances
InfHomClass F α β
states that F
is a type of ⊓
-preserving morphisms.
You should extend this class when you extend InfHom
.
An
InfHomClass
morphism preserves infima.
Instances
SupBotHomClass F α β
states that F
is a type of finitary supremum-preserving morphisms.
You should extend this class when you extend SupBotHom
.
A
SupBotHomClass
morphism preserves the bottom element.
Instances
InfTopHomClass F α β
states that F
is a type of finitary infimum-preserving morphisms.
You should extend this class when you extend SupBotHom
.
An
InfTopHomClass
morphism preserves the top element.
Instances
LatticeHomClass F α β
states that F
is a type of lattice morphisms.
You should extend this class when you extend LatticeHom
.
A
LatticeHomClass
morphism preserves infima.
Instances
BoundedLatticeHomClass F α β
states that F
is a type of bounded lattice morphisms.
You should extend this class when you extend BoundedLatticeHom
.
A
BoundedLatticeHomClass
morphism preserves the top element.A
BoundedLatticeHomClass
morphism preserves the bottom element.
Instances
Equations
- ⋯ = ⋯
Equations
- ⋯ = ⋯
Equations
- ⋯ = ⋯
Equations
- ⋯ = ⋯
Equations
- ⋯ = ⋯
Equations
- ⋯ = ⋯
Equations
- ⋯ = ⋯
Equations
- ⋯ = ⋯
Equations
- ⋯ = ⋯
Equations
- ⋯ = ⋯
Equations
- ⋯ = ⋯
Equations
- ⋯ = ⋯
Equations
- ⋯ = ⋯
Equations
- ⋯ = ⋯
We can regard an injective map preserving binary infima as an order embedding.
Equations
Instances For
Special case of map_compl
for boolean algebras.
Special case of map_sdiff
for boolean algebras.
Special case of map_symmDiff
for boolean algebras.
Equations
- instCoeTCLatticeHomOfLatticeHomClass = { coe := fun (f : F) => { toFun := ⇑f, map_sup' := ⋯, map_inf' := ⋯ } }
Equations
- One or more equations did not get rendered due to their size.
Supremum homomorphisms #
Equations
- ⋯ = ⋯
Equations
- SupHom.instInhabited α = { default := SupHom.id α }
The constant function as a SupHom
.
Equations
- SupHom.const α b = { toFun := fun (x : α) => b, map_sup' := ⋯ }
Instances For
Equations
- SupHom.instSemilatticeSup = Function.Injective.semilatticeSup (fun (f : SupHom α β) => ⇑f) ⋯ ⋯
Equations
- SupHom.instBot = { bot := SupHom.const α ⊥ }
Equations
- SupHom.instTop = { top := SupHom.const α ⊤ }
Equations
- SupHom.instOrderBot = OrderBot.lift DFunLike.coe ⋯ ⋯
Equations
- SupHom.instOrderTop = OrderTop.lift DFunLike.coe ⋯ ⋯
Equations
- SupHom.instBoundedOrder = BoundedOrder.lift DFunLike.coe ⋯ ⋯ ⋯
Subtype.val
as a SupHom
.
Equations
- SupHom.subtypeVal Psup = { toFun := Subtype.val, map_sup' := ⋯ }
Instances For
Infimum homomorphisms #
Equations
- ⋯ = ⋯
Equations
- InfHom.instInhabited α = { default := InfHom.id α }
The constant function as an InfHom
.
Equations
- InfHom.const α b = { toFun := fun (x : α) => b, map_inf' := ⋯ }
Instances For
Equations
- InfHom.instSemilatticeInf = Function.Injective.semilatticeInf (fun (f : InfHom α β) => ⇑f) ⋯ ⋯
Equations
- InfHom.instBot = { bot := InfHom.const α ⊥ }
Equations
- InfHom.instTop = { top := InfHom.const α ⊤ }
Equations
- InfHom.instOrderBot = OrderBot.lift DFunLike.coe ⋯ ⋯
Equations
- InfHom.instOrderTop = OrderTop.lift DFunLike.coe ⋯ ⋯
Equations
- InfHom.instBoundedOrder = BoundedOrder.lift DFunLike.coe ⋯ ⋯ ⋯
Subtype.val
as an InfHom
.
Equations
- InfHom.subtypeVal Pinf = { toFun := Subtype.val, map_inf' := ⋯ }
Instances For
Finitary supremum homomorphisms #
Copy of a SupBotHom
with a new toFun
equal to the old one. Useful to fix definitional
equalities.
Equations
- f.copy f' h = { toSupHom := f.copy f' h, map_bot' := ⋯ }
Instances For
Equations
- SupBotHom.instInhabited α = { default := SupBotHom.id α }
Equations
- SupBotHom.instSemilatticeSup = Function.Injective.semilatticeSup (fun (f : SupBotHom α β) => ⇑f) ⋯ ⋯
Equations
- SupBotHom.instOrderBot = OrderBot.mk ⋯
Subtype.val
as a SupBotHom
.
Equations
- SupBotHom.subtypeVal Pbot Psup = { toSupHom := SupHom.subtypeVal Psup, map_bot' := ⋯ }
Instances For
Finitary infimum homomorphisms #
Copy of an InfTopHom
with a new toFun
equal to the old one. Useful to fix definitional
equalities.
Equations
- f.copy f' h = { toInfHom := f.copy f' h, map_top' := ⋯ }
Instances For
Equations
- InfTopHom.instInhabited α = { default := InfTopHom.id α }
Equations
- InfTopHom.instSemilatticeInf = Function.Injective.semilatticeInf (fun (f : InfTopHom α β) => ⇑f) ⋯ ⋯
Equations
- InfTopHom.instOrderTop = OrderTop.mk ⋯
Subtype.val
as an InfTopHom
.
Equations
- InfTopHom.subtypeVal Ptop Pinf = { toInfHom := InfHom.subtypeVal Pinf, map_top' := ⋯ }
Instances For
Lattice homomorphisms #
Reinterpret a LatticeHom
as an InfHom
.
Equations
- f.toInfHom = { toFun := f.toFun, map_inf' := ⋯ }
Instances For
Equations
- LatticeHom.instFunLike = { coe := fun (f : LatticeHom α β) => f.toFun, coe_injective' := ⋯ }
Equations
- ⋯ = ⋯
Copy of a LatticeHom
with a new toFun
equal to the old one. Useful to fix definitional
equalities.
Equations
- f.copy f' h = { toSupHom := f.copy f' h, map_inf' := ⋯ }
Instances For
id
as a LatticeHom
.
Equations
- LatticeHom.id α = { toFun := id, map_sup' := ⋯, map_inf' := ⋯ }
Instances For
Equations
- LatticeHom.instInhabited α = { default := LatticeHom.id α }
Composition of LatticeHom
s as a LatticeHom
.
Equations
- f.comp g = { toSupHom := f.comp g.toSupHom, map_inf' := ⋯ }
Instances For
Subtype.val
as a LatticeHom
.
Equations
- LatticeHom.subtypeVal Psup Pinf = { toSupHom := SupHom.subtypeVal Psup, map_inf' := ⋯ }
Instances For
An order homomorphism from a linear order is a lattice homomorphism.
Equations
- ⋯ = ⋯
Reinterpret an order homomorphism to a linear order as a LatticeHom
.
Equations
- OrderHomClass.toLatticeHom α β f = { toFun := ⇑f, map_sup' := ⋯, map_inf' := ⋯ }
Instances For
Bounded lattice homomorphisms #
Reinterpret a BoundedLatticeHom
as a SupBotHom
.
Equations
- f.toSupBotHom = { toSupHom := f.toSupHom, map_bot' := ⋯ }
Instances For
Reinterpret a BoundedLatticeHom
as an InfTopHom
.
Equations
- f.toInfTopHom = { toFun := f.toFun, map_inf' := ⋯, map_top' := ⋯ }
Instances For
Reinterpret a BoundedLatticeHom
as a BoundedOrderHom
.
Equations
- f.toBoundedOrderHom = { toFun := f.toFun, monotone' := ⋯, map_top' := ⋯, map_bot' := ⋯ }
Instances For
Equations
- BoundedLatticeHom.instFunLike = { coe := fun (f : BoundedLatticeHom α β) => f.toFun, coe_injective' := ⋯ }
Equations
- ⋯ = ⋯
Copy of a BoundedLatticeHom
with a new toFun
equal to the old one. Useful to fix
definitional equalities.
Equations
- f.copy f' h = { toLatticeHom := f.copy f' h, map_top' := ⋯, map_bot' := ⋯ }
Instances For
id
as a BoundedLatticeHom
.
Equations
- BoundedLatticeHom.id α = { toLatticeHom := LatticeHom.id α, map_top' := ⋯, map_bot' := ⋯ }
Instances For
Equations
- BoundedLatticeHom.instInhabited α = { default := BoundedLatticeHom.id α }
Composition of BoundedLatticeHom
s as a BoundedLatticeHom
.
Equations
- f.comp g = { toLatticeHom := f.comp g.toLatticeHom, map_top' := ⋯, map_bot' := ⋯ }
Instances For
Subtype.val
as a BoundedLatticeHom
.
Equations
- BoundedLatticeHom.subtypeVal Pbot Ptop Psup Pinf = { toLatticeHom := LatticeHom.subtypeVal Psup Pinf, map_top' := ⋯, map_bot' := ⋯ }
Instances For
Dual homs #
Reinterpret a supremum homomorphism as an infimum homomorphism between the dual lattices.
Equations
Instances For
Reinterpret an infimum homomorphism as a supremum homomorphism between the dual lattices.
Equations
Instances For
Reinterpret a lattice homomorphism as a lattice homomorphism between the dual lattices.
Equations
- One or more equations did not get rendered due to their size.
Instances For
Reinterpret a bounded lattice homomorphism as a bounded lattice homomorphism between the dual bounded lattices.
Equations
- One or more equations did not get rendered due to their size.
Instances For
Prod #
Natural projection homomorphism from α × β
to α
.
Equations
- LatticeHom.fst = { toFun := Prod.fst, map_sup' := ⋯, map_inf' := ⋯ }
Instances For
Natural projection homomorphism from α × β
to β
.
Equations
- LatticeHom.snd = { toFun := Prod.snd, map_sup' := ⋯, map_inf' := ⋯ }
Instances For
Pi #
Evaluation as a lattice homomorphism.
Equations
- Pi.evalLatticeHom i = { toFun := Function.eval i, map_sup' := ⋯, map_inf' := ⋯ }
Instances For
Adjoins a ⊤
to the domain and codomain of a SupHom
.
Equations
- f.withTop = { toFun := WithTop.map ⇑f, map_sup' := ⋯ }
Instances For
Adjoins a ⊥
to the domain and codomain of a SupHom
.
Equations
- f.withBot = { toFun := Option.map ⇑f, map_sup' := ⋯, map_bot' := ⋯ }
Instances For
Adjoins a ⊤
to the codomain of a SupHom
.
Equations
- f.withTop' = { toFun := fun (a : WithTop α) => Option.elim a ⊤ ⇑f, map_sup' := ⋯ }
Instances For
Adjoins a ⊥
to the domain of a SupHom
.
Equations
- f.withBot' = { toFun := fun (a : WithBot α) => Option.elim a ⊥ ⇑f, map_sup' := ⋯, map_bot' := ⋯ }
Instances For
Adjoins a ⊤
to the domain and codomain of an InfHom
.
Equations
- f.withTop = { toFun := Option.map ⇑f, map_inf' := ⋯, map_top' := ⋯ }
Instances For
Adjoins a ⊥
to the domain and codomain of an InfHom
.
Equations
- f.withBot = { toFun := Option.map ⇑f, map_inf' := ⋯ }
Instances For
Adjoins a ⊤
to the codomain of an InfHom
.
Equations
- f.withTop' = { toFun := fun (a : WithTop α) => Option.elim a ⊤ ⇑f, map_inf' := ⋯, map_top' := ⋯ }
Instances For
Adjoins a ⊥
to the codomain of an InfHom
.
Equations
- f.withBot' = { toFun := fun (a : WithBot α) => Option.elim a ⊥ ⇑f, map_inf' := ⋯ }
Instances For
Adjoins a ⊤
to the domain and codomain of a LatticeHom
.
Equations
- f.withTop = { toSupHom := f.withTop, map_inf' := ⋯ }
Instances For
Adjoins a ⊥
to the domain and codomain of a LatticeHom
.
Equations
- f.withBot = { toFun := ⇑f.withBot, map_sup' := ⋯, map_inf' := ⋯ }
Instances For
Adjoins a ⊤
and ⊥
to the domain and codomain of a LatticeHom
.
Equations
- f.withTopWithBot = { toLatticeHom := f.withBot.withTop, map_top' := ⋯, map_bot' := ⋯ }
Instances For
Adjoins a ⊥
to the codomain of a LatticeHom
.
Equations
- f.withTop' = { toSupHom := f.withTop', map_inf' := ⋯ }
Instances For
Adjoins a ⊥
to the domain and codomain of a LatticeHom
.
Equations
- f.withBot' = { toSupHom := f.withBot'.toSupHom, map_inf' := ⋯ }
Instances For
Adjoins a ⊤
and ⊥
to the codomain of a LatticeHom
.
Equations
- f.withTopWithBot' = { toLatticeHom := f.withBot'.withTop', map_top' := ⋯, map_bot' := ⋯ }