Lemmas relating fintypes and order/lattice structure. #
theorem
Finset.sup_univ_eq_iSup
{α : Type u_1}
{β : Type u_2}
[Fintype α]
[CompleteLattice β]
(f : α → β)
:
Finset.sup Finset.univ f = iSup f
A special case of Finset.sup_eq_iSup
that omits the useless x ∈ univ
binder.
theorem
Finset.inf_univ_eq_iInf
{α : Type u_1}
{β : Type u_2}
[Fintype α]
[CompleteLattice β]
(f : α → β)
:
Finset.inf Finset.univ f = iInf f
A special case of Finset.inf_eq_iInf
that omits the useless x ∈ univ
binder.
@[simp]
theorem
Finset.fold_inf_univ
{α : Type u_1}
[Fintype α]
[SemilatticeInf α]
[OrderBot α]
(a : α)
:
Finset.fold (fun x x_1 => x ⊓ x_1) a (fun x => x) Finset.univ = ⊥
@[simp]
theorem
Finset.fold_sup_univ
{α : Type u_1}
[Fintype α]
[SemilatticeSup α]
[OrderTop α]
(a : α)
:
Finset.fold (fun x x_1 => x ⊔ x_1) a (fun x => x) Finset.univ = ⊤
theorem
Finite.exists_max
{α : Type u_1}
{β : Type u_2}
[Finite α]
[Nonempty α]
[LinearOrder β]
(f : α → β)
:
∃ x₀, ∀ (x : α), f x ≤ f x₀
theorem
Finite.exists_min
{α : Type u_1}
{β : Type u_2}
[Finite α]
[Nonempty α]
[LinearOrder β]
(f : α → β)
:
∃ x₀, ∀ (x : α), f x₀ ≤ f x