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Filter.EventuallyEq.isLocalExtr_iff {f g : α → β} {a : α} (heq : f =ᶠ[𝓝 a] g) : IsLocalExtr f a ↔ IsLocalExtr g a := heq.isExtrFilter_iff heq.eq_of_nhds
theorem
Topology
[ "Mathlib.Algebra.Group.Defs", "Mathlib.Order.Filter.Extr", "Mathlib.Topology.ContinuousOn" ]
Mathlib/Topology/Order/LocalExtr.lean
Filter.EventuallyEq.isLocalExtr_iff
null
isLocalMax_of_mono_anti' {α : Type*} [TopologicalSpace α] [LinearOrder α] {β : Type*} [Preorder β] {b : α} {f : α → β} {a : Set α} (ha : a ∈ 𝓝[≤] b) {c : Set α} (hc : c ∈ 𝓝[≥] b) (h₀ : MonotoneOn f a) (h₁ : AntitoneOn f c) : IsLocalMax f b := have : b ∈ a := mem_of_mem_nhdsWithin (by simp) ha have : b ∈ c := mem_of_mem_nhdsWithin (by simp) hc mem_of_superset (nhds_of_Ici_Iic ha hc) (fun x _ => by rcases le_total x b <;> aesop)
lemma
Topology
[ "Mathlib.Algebra.Group.Defs", "Mathlib.Order.Filter.Extr", "Mathlib.Topology.ContinuousOn" ]
Mathlib/Topology/Order/LocalExtr.lean
isLocalMax_of_mono_anti'
If `f` is monotone to the left and antitone to the right, then it has a local maximum.
isLocalMin_of_anti_mono' {α : Type*} [TopologicalSpace α] [LinearOrder α] {β : Type*} [Preorder β] {b : α} {f : α → β} {a : Set α} (ha : a ∈ 𝓝[≤] b) {c : Set α} (hc : c ∈ 𝓝[≥] b) (h₀ : AntitoneOn f a) (h₁ : MonotoneOn f c) : IsLocalMin f b := have : b ∈ a := mem_of_mem_nhdsWithin (by simp) ha have : b ∈ c := mem_of_mem_nhdsWithin (by simp) hc mem_of_superset (nhds_of_Ici_Iic ha hc) (fun x _ => by rcases le_total x b <;> aesop)
lemma
Topology
[ "Mathlib.Algebra.Group.Defs", "Mathlib.Order.Filter.Extr", "Mathlib.Topology.ContinuousOn" ]
Mathlib/Topology/Order/LocalExtr.lean
isLocalMin_of_anti_mono'
If `f` is antitone to the left and monotone to the right, then it has a local minimum.
lower (α : Type*) [Preorder α] : TopologicalSpace α := generateFrom {s | ∃ a, (Ici a)ᶜ = s}
def
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
lower
The lower topology is the topology generated by the complements of the left-closed right-infinite intervals.
upper (α : Type*) [Preorder α] : TopologicalSpace α := generateFrom {s | ∃ a, (Iic a)ᶜ = s}
def
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
upper
The upper topology is the topology generated by the complements of the right-closed left-infinite intervals.
WithLower (α : Type*) := α variable {α β : Type*}
def
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
WithLower
Type synonym for a preorder equipped with the lower set topology.
@[match_pattern] toLower : α ≃ WithLower α := Equiv.refl _
def
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
toLower
`toLower` is the identity function to the `WithLower` of a type.
@[match_pattern] ofLower : WithLower α ≃ α := Equiv.refl _ @[simp] lemma toLower_symm : (@toLower α).symm = ofLower := rfl @[simp] lemma ofLower_symm : (@ofLower α).symm = toLower := rfl @[simp] lemma toLower_ofLower (a : WithLower α) : toLower (ofLower a) = a := rfl @[simp] lemma ofLower_toLower (a : α) : ofLower (toLower a) = a := rfl
def
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
ofLower
`ofLower` is the identity function from the `WithLower` of a type.
toLower_inj {a b : α} : toLower a = toLower b ↔ a = b := Iff.rfl
lemma
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
toLower_inj
null
ofLower_inj {a b : WithLower α} : ofLower a = ofLower b ↔ a = b := Iff.rfl
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
ofLower_inj
null
@[elab_as_elim, cases_eliminator, induction_eliminator] protected rec {β : WithLower α → Sort*} (h : ∀ a, β (toLower a)) : ∀ a, β a := fun a => h (ofLower a)
def
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
rec
A recursor for `WithLower`. Use as `induction x`.
@[simp] toLower_le_toLower {x y : α} : toLower x ≤ toLower y ↔ x ≤ y := .rfl @[simp] lemma toLower_lt_toLower {x y : α} : toLower x < toLower y ↔ x < y := .rfl @[simp] lemma ofLower_le_ofLower {x y : WithLower α} : ofLower x ≤ ofLower y ↔ x ≤ y := .rfl @[simp] lemma ofLower_lt_ofLower {x y : WithLower α} : ofLower x < ofLower y ↔ x < y := .rfl
lemma
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
toLower_le_toLower
null
isOpen_preimage_ofLower : IsOpen (ofLower ⁻¹' s) ↔ IsOpen[lower α] s := Iff.rfl
lemma
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
isOpen_preimage_ofLower
null
isOpen_def (T : Set (WithLower α)) : IsOpen T ↔ IsOpen[lower α] (WithLower.toLower ⁻¹' T) := Iff.rfl
lemma
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
isOpen_def
null
continuous_toLower [TopologicalSpace α] [ClosedIciTopology α] : Continuous (toLower : α → WithLower α) := continuous_generateFrom_iff.mpr <| by rintro _ ⟨a, rfl⟩; exact isClosed_Ici.isOpen_compl
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
continuous_toLower
null
WithUpper (α : Type*) := α
def
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
WithUpper
Type synonym for a preorder equipped with the upper topology.
@[match_pattern] toUpper : α ≃ WithUpper α := Equiv.refl _
def
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
toUpper
`toUpper` is the identity function to the `WithUpper` of a type.
@[match_pattern] ofUpper : WithUpper α ≃ α := Equiv.refl _ @[simp] lemma toUpper_symm {α} : (@toUpper α).symm = ofUpper := rfl @[simp] lemma ofUpper_symm : (@ofUpper α).symm = toUpper := rfl @[simp] lemma toUpper_ofUpper (a : WithUpper α) : toUpper (ofUpper a) = a := rfl @[simp] lemma ofUpper_toUpper (a : α) : ofUpper (toUpper a) = a := rfl
def
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
ofUpper
`ofUpper` is the identity function from the `WithUpper` of a type.
toUpper_inj {a b : α} : toUpper a = toUpper b ↔ a = b := Iff.rfl
lemma
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
toUpper_inj
null
ofUpper_inj {a b : WithUpper α} : ofUpper a = ofUpper b ↔ a = b := Iff.rfl
lemma
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
ofUpper_inj
null
@[elab_as_elim, cases_eliminator, induction_eliminator] protected rec {β : WithUpper α → Sort*} (h : ∀ a, β (toUpper a)) : ∀ a, β a := fun a => h (ofUpper a)
def
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
rec
A recursor for `WithUpper`. Use as `induction x`.
@[simp] toUpper_le_toUpper {x y : α} : toUpper x ≤ toUpper y ↔ x ≤ y := .rfl @[simp] lemma toUpper_lt_toUpper {x y : α} : toUpper x < toUpper y ↔ x < y := .rfl @[simp] lemma ofUpper_le_ofUpper {x y : WithUpper α} : ofUpper x ≤ ofUpper y ↔ x ≤ y := .rfl @[simp] lemma ofUpper_lt_ofUpper {x y : WithUpper α} : ofUpper x < ofUpper y ↔ x < y := .rfl
lemma
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
toUpper_le_toUpper
null
isOpen_preimage_ofUpper : IsOpen (ofUpper ⁻¹' s) ↔ (upper α).IsOpen s := Iff.rfl
lemma
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
isOpen_preimage_ofUpper
null
isOpen_def {s : Set (WithUpper α)} : IsOpen s ↔ (upper α).IsOpen (toUpper ⁻¹' s) := Iff.rfl
lemma
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
isOpen_def
null
continuous_toUpper [TopologicalSpace α] [ClosedIicTopology α] : Continuous (toUpper : α → WithUpper α) := continuous_generateFrom_iff.mpr <| by rintro _ ⟨a, rfl⟩; exact isClosed_Iic.isOpen_compl
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
continuous_toUpper
null
IsLower (α : Type*) [t : TopologicalSpace α] [Preorder α] : Prop where topology_eq_lowerTopology : t = lower α attribute [nolint docBlame] IsLower.topology_eq_lowerTopology
class
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
IsLower
The lower topology is the topology generated by the complements of the left-closed right-infinite intervals.
IsUpper (α : Type*) [t : TopologicalSpace α] [Preorder α] : Prop where topology_eq_upperTopology : t = upper α attribute [nolint docBlame] IsUpper.topology_eq_upperTopology
class
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
IsUpper
The upper topology is the topology generated by the complements of the right-closed left-infinite intervals.
WithLower.toDualHomeomorph [Preorder α] : WithLower α ≃ₜ WithUpper αᵒᵈ where toFun := OrderDual.toDual invFun := OrderDual.ofDual left_inv := OrderDual.toDual_ofDual right_inv := OrderDual.ofDual_toDual continuous_toFun := continuous_coinduced_rng continuous_invFun := continuous_coinduced_rng
def
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
WithLower.toDualHomeomorph
The lower topology is homeomorphic to the upper topology on the dual order
lowerBasis (α : Type*) [Preorder α] := { s : Set α | ∃ t : Set α, t.Finite ∧ (upperClosure t : Set α)ᶜ = s }
def
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
lowerBasis
The complements of the upper closures of finite sets are a collection of lower sets which form a basis for the lower topology.
topology_eq : ‹_› = lower α := topology_eq_lowerTopology variable {α}
lemma
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
topology_eq
null
withLowerHomeomorph : WithLower α ≃ₜ α := WithLower.ofLower.toHomeomorphOfIsInducing ⟨topology_eq α ▸ induced_id.symm⟩
def
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
withLowerHomeomorph
If `α` is equipped with the lower topology, then it is homeomorphic to `WithLower α`.
isOpen_iff_generate_Ici_compl : IsOpen s ↔ GenerateOpen { t | ∃ a, (Ici a)ᶜ = t } s := by rw [topology_eq α]; rfl
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
isOpen_iff_generate_Ici_compl
null
_root_.OrderDual.instIsUpper [Preorder α] [TopologicalSpace α] [IsLower α] : IsUpper αᵒᵈ where topology_eq_upperTopology := topology_eq_lowerTopology (α := α)
instance
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
_root_.OrderDual.instIsUpper
null
isClosed_upperClosure (h : s.Finite) : IsClosed (upperClosure s : Set α) := by simp only [← UpperSet.iInf_Ici, UpperSet.coe_iInf] exact h.isClosed_biUnion fun _ _ => isClosed_Ici
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
isClosed_upperClosure
Left-closed right-infinite intervals [a, ∞) are closed in the lower topology. -/ instance : ClosedIciTopology α := ⟨fun a ↦ isOpen_compl_iff.1 <| isOpen_iff_generate_Ici_compl.2 <| GenerateOpen.basic _ ⟨a, rfl⟩⟩ /-- The upper closure of a finite set is closed in the lower topology.
isLowerSet_of_isOpen (h : IsOpen s) : IsLowerSet s := by replace h := isOpen_iff_generate_Ici_compl.1 h induction h with | basic u h' => obtain ⟨a, rfl⟩ := h'; exact (isUpperSet_Ici a).compl | univ => exact isLowerSet_univ | inter u v _ _ hu2 hv2 => exact hu2.inter hv2 | sUnion _ _ ih => exact isLowerSet_sUnion ih
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
isLowerSet_of_isOpen
Every set open in the lower topology is a lower set.
isUpperSet_of_isClosed (h : IsClosed s) : IsUpperSet s := isLowerSet_compl.1 <| isLowerSet_of_isOpen h.isOpen_compl
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
isUpperSet_of_isClosed
null
tendsto_nhds_iff_not_le {β : Type*} {f : β → α} {l : Filter β} {x : α} : Filter.Tendsto f l (𝓝 x) ↔ ∀ y, ¬y ≤ x → ∀ᶠ z in l, ¬y ≤ f z := by simp [topology_eq_lowerTopology, tendsto_nhds_generateFrom_iff, Filter.Eventually, Ici, compl_setOf]
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
tendsto_nhds_iff_not_le
null
@[simp] closure_singleton (a : α) : closure {a} = Ici a := Subset.antisymm ((closure_minimal fun _ h => h.ge) <| isClosed_Ici) <| (isUpperSet_of_isClosed isClosed_closure).Ici_subset <| subset_closure rfl
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
closure_singleton
The closure of a singleton `{a}` in the lower topology is the left-closed right-infinite interval [a, ∞).
protected isTopologicalBasis : IsTopologicalBasis (lowerBasis α) := by convert isTopologicalBasis_of_subbasis (topology_eq α) simp_rw [lowerBasis, coe_upperClosure, compl_iUnion] ext s constructor · rintro ⟨F, hF, rfl⟩ refine ⟨(fun a => (Ici a)ᶜ) '' F, ⟨hF.image _, image_subset_iff.2 fun _ _ => ⟨_, rfl⟩⟩, ?_⟩ simp only [sInter_image] · rintro ⟨F, ⟨hF, hs⟩, rfl⟩ haveI := hF.to_subtype rw [subset_def, Subtype.forall'] at hs choose f hf using hs exact ⟨_, finite_range f, by simp_rw [biInter_range, hf, sInter_eq_iInter]⟩
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
isTopologicalBasis
null
continuous_iff_Ici [TopologicalSpace β] {f : β → α} : Continuous f ↔ ∀ a, IsClosed (f ⁻¹' (Ici a)) := by obtain rfl := IsLower.topology_eq α simp [continuous_generateFrom_iff]
lemma
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
continuous_iff_Ici
A function `f : β → α` with lower topology in the codomain is continuous if and only if the preimage of every interval `Set.Ici a` is a closed set.
upperBasis (α : Type*) [Preorder α] := { s : Set α | ∃ t : Set α, t.Finite ∧ (lowerClosure t : Set α)ᶜ = s }
def
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
upperBasis
The lower topology on a partial order is T₀. -/ instance (priority := 90) t0Space : T0Space α := (t0Space_iff_inseparable α).2 fun x y h => Ici_injective <| by simpa only [inseparable_iff_closure_eq, closure_singleton] using h end PartialOrder section LinearOrder variable [LinearOrder α] [TopologicalSpace α] [IsLower α] lemma isTopologicalBasis_insert_univ_subbasis : IsTopologicalBasis (insert univ {s : Set α | ∃ a, (Ici a)ᶜ = s}) := isTopologicalBasis_of_subbasis_of_inter (by rw [topology_eq α, lower]) (by rintro _ ⟨b, rfl⟩ _ ⟨c, rfl⟩ use b ⊓ c rw [compl_Ici, compl_Ici, compl_Ici, Iio_inter_Iio]) theorem tendsto_nhds_iff_lt {β : Type*} {f : β → α} {l : Filter β} {x : α} : Filter.Tendsto f l (𝓝 x) ↔ ∀ y, x < y → ∀ᶠ z in l, f z < y := by simp only [tendsto_nhds_iff_not_le, not_le] end LinearOrder section CompleteLinearOrder variable [CompleteLinearOrder α] [t : TopologicalSpace α] [IsLower α] lemma isTopologicalSpace_basis (U : Set α) : IsOpen U ↔ U = univ ∨ ∃ a, (Ici a)ᶜ = U := by by_cases hU : U = univ · simp only [hU, isOpen_univ, compl_Ici, true_or] refine ⟨?_, isTopologicalBasis_insert_univ_subbasis.isOpen⟩ intro hO apply Or.inr convert IsTopologicalBasis.open_eq_sUnion isTopologicalBasis_insert_univ_subbasis hO constructor · intro ⟨a, ha⟩ use {U} constructor · apply subset_trans (singleton_subset_iff.mpr _) (subset_insert _ _) use a · rw [sUnion_singleton] · intro ⟨S, hS1, hS2⟩ have hUS : univ ∉ S := by by_contra hUS' apply hU rw [hS2] exact sUnion_eq_univ_iff.mpr (fun a => ⟨univ, hUS', trivial⟩) use sSup {a | (Ici a)ᶜ ∈ S} rw [hS2, sUnion_eq_compl_sInter_compl, compl_inj_iff] apply le_antisymm · intro b hb simp only [sInter_image, mem_iInter, mem_compl_iff] intro s hs obtain ⟨a, ha⟩ := (subset_insert_iff_of_notMem hUS).mp hS1 hs subst hS2 ha simp_all only [compl_Ici, mem_Ici, sSup_le_iff, mem_setOf_eq, mem_Iio, not_lt] · intro b hb rw [mem_Ici, sSup_le_iff] intro c hc simp only [sInter_image, mem_iInter] at hb rw [← not_lt, ← mem_Iio, ← compl_Ici] exact hb _ hc end CompleteLinearOrder end IsLower namespace IsUpper /-- The complements of the lower closures of finite sets are a collection of upper sets which form a basis for the upper topology.
topology_eq : ‹_› = upper α := topology_eq_upperTopology variable {α}
lemma
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
topology_eq
null
withUpperHomeomorph : WithUpper α ≃ₜ α := WithUpper.ofUpper.toHomeomorphOfIsInducing ⟨topology_eq α ▸ induced_id.symm⟩
def
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
withUpperHomeomorph
If `α` is equipped with the upper topology, then it is homeomorphic to `WithUpper α`.
isOpen_iff_generate_Iic_compl : IsOpen s ↔ GenerateOpen { t | ∃ a, (Iic a)ᶜ = t } s := by rw [topology_eq α]; rfl
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
isOpen_iff_generate_Iic_compl
null
_root_.OrderDual.instIsLower [Preorder α] [TopologicalSpace α] [IsUpper α] : IsLower αᵒᵈ where topology_eq_lowerTopology := topology_eq_upperTopology (α := α)
instance
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
_root_.OrderDual.instIsLower
null
isClosed_lowerClosure (h : s.Finite) : IsClosed (lowerClosure s : Set α) := IsLower.isClosed_upperClosure (α := αᵒᵈ) h
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
isClosed_lowerClosure
Left-infinite right-closed intervals (-∞,a] are closed in the upper topology. -/ instance : ClosedIicTopology α := ⟨fun a ↦ isOpen_compl_iff.1 <| isOpen_iff_generate_Iic_compl.2 <| GenerateOpen.basic _ ⟨a, rfl⟩⟩ /-- The lower closure of a finite set is closed in the upper topology.
isUpperSet_of_isOpen (h : IsOpen s) : IsUpperSet s := IsLower.isLowerSet_of_isOpen (α := αᵒᵈ) h
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
isUpperSet_of_isOpen
Every set open in the upper topology is a upper set.
isLowerSet_of_isClosed (h : IsClosed s) : IsLowerSet s := isUpperSet_compl.1 <| isUpperSet_of_isOpen h.isOpen_compl
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
isLowerSet_of_isClosed
null
tendsto_nhds_iff_not_le {β : Type*} {f : β → α} {l : Filter β} {x : α} : Filter.Tendsto f l (𝓝 x) ↔ ∀ y, ¬x ≤ y → ∀ᶠ z in l, ¬f z ≤ y := IsLower.tendsto_nhds_iff_not_le (α := αᵒᵈ)
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
tendsto_nhds_iff_not_le
null
@[simp] closure_singleton (a : α) : closure {a} = Iic a := IsLower.closure_singleton (α := αᵒᵈ) _
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
closure_singleton
The closure of a singleton `{a}` in the upper topology is the left-infinite right-closed interval (-∞,a].
protected isTopologicalBasis : IsTopologicalBasis (upperBasis α) := IsLower.isTopologicalBasis (α := αᵒᵈ)
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
isTopologicalBasis
null
continuous_iff_Iic [TopologicalSpace β] {f : β → α} : Continuous f ↔ ∀ a, IsClosed (f ⁻¹' (Iic a)) := IsLower.continuous_iff_Ici (α := αᵒᵈ)
lemma
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
continuous_iff_Iic
A function `f : β → α` with upper topology in the codomain is continuous if and only if the preimage of every interval `Set.Iic a` is a closed set.
isTopologicalBasis_insert_univ_subbasis : IsTopologicalBasis (insert univ {s : Set α | ∃ a, (Iic a)ᶜ = s}) := IsLower.isTopologicalBasis_insert_univ_subbasis (α := αᵒᵈ)
lemma
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
isTopologicalBasis_insert_univ_subbasis
null
tendsto_nhds_iff_lt {β : Type*} {f : β → α} {l : Filter β} {x : α} : Filter.Tendsto f l (𝓝 x) ↔ ∀ y < x, ∀ᶠ z in l, y < f z := IsLower.tendsto_nhds_iff_lt (α := αᵒᵈ)
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
tendsto_nhds_iff_lt
null
isTopologicalSpace_basis (U : Set α) : IsOpen U ↔ U = univ ∨ ∃ a, (Iic a)ᶜ = U := IsLower.isTopologicalSpace_basis (α := αᵒᵈ) U
lemma
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
isTopologicalSpace_basis
null
instIsLowerProd [Preorder α] [TopologicalSpace α] [IsLower α] [OrderBot α] [Preorder β] [TopologicalSpace β] [IsLower β] [OrderBot β] : IsLower (α × β) where topology_eq_lowerTopology := by refine le_antisymm (le_generateFrom ?_) ?_ · rintro _ ⟨x, rfl⟩ exact (isClosed_Ici.prod isClosed_Ici).isOpen_compl rw [(IsLower.isTopologicalBasis.prod IsLower.isTopologicalBasis).eq_generateFrom, le_generateFrom_iff_subset_isOpen, image2_subset_iff] rintro _ ⟨s, hs, rfl⟩ _ ⟨t, ht, rfl⟩ dsimp simp_rw [coe_upperClosure, compl_iUnion, prod_eq, preimage_iInter, preimage_compl] let _ : TopologicalSpace (α × β) := lower (α × β) refine (hs.isOpen_biInter fun a _ => ?_).inter (ht.isOpen_biInter fun b _ => ?_) · exact GenerateOpen.basic _ ⟨(a, ⊥), by simp [Ici_prod_eq, prod_univ]⟩ · exact GenerateOpen.basic _ ⟨(⊥, b), by simp [Ici_prod_eq, univ_prod]⟩
instance
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
instIsLowerProd
null
instIsUpperProd [Preorder α] [TopologicalSpace α] [IsUpper α] [OrderTop α] [Preorder β] [TopologicalSpace β] [IsUpper β] [OrderTop β] : IsUpper (α × β) where topology_eq_upperTopology := by suffices IsLower (α × β)ᵒᵈ from IsLower.topology_eq_lowerTopology (α := (α × β)ᵒᵈ) exact instIsLowerProd (α := αᵒᵈ) (β := βᵒᵈ)
instance
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
instIsUpperProd
null
protected _root_.sInfHom.continuous (f : sInfHom α β) : Continuous f := by refine IsLower.continuous_iff_Ici.2 fun b => ?_ convert isClosed_Ici (a := sInf <| f ⁻¹' Ici b) refine Subset.antisymm (fun a => sInf_le) fun a ha => le_trans ?_ <| OrderHomClass.mono (f : α →o β) ha refine LE.le.trans ?_ (map_sInf f _).ge simp
lemma
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
_root_.sInfHom.continuous
null
protected _root_.sSupHom.continuous (f : sSupHom α β) : Continuous f := sInfHom.continuous (α := αᵒᵈ) (β := βᵒᵈ) (sSupHom.dual.toFun f)
lemma
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
_root_.sSupHom.continuous
null
isUpper_orderDual [Preorder α] [TopologicalSpace α] : IsUpper αᵒᵈ ↔ IsLower α := by constructor · apply OrderDual.instIsLower · apply OrderDual.instIsUpper
lemma
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
isUpper_orderDual
null
isLower_orderDual [Preorder α] [TopologicalSpace α] : IsLower αᵒᵈ ↔ IsUpper α := isUpper_orderDual.symm
lemma
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Homeomorph.Defs", "Mathlib.Topology.Order.Lattice" ]
Mathlib/Topology/Order/LowerUpperTopology.lean
isLower_orderDual
null
MonotoneOn.insert_of_continuousWithinAt [TopologicalSpace β] [OrderClosedTopology β] (hf : MonotoneOn f s) (hx : ClusterPt x (𝓟 s)) (h'x : ContinuousWithinAt f s x) : MonotoneOn f (insert x s) := by have : (𝓝[s] x).NeBot := hx apply monotoneOn_insert_iff.2 ⟨fun b hb hbx ↦ ?_, fun b hb hxb ↦ ?_, hf⟩ · rcases hbx.eq_or_lt with rfl | hbx · exact le_rfl simp only [ContinuousWithinAt] at h'x apply ge_of_tendsto h'x have : s ∩ Ioi b ∈ 𝓝[s] x := inter_mem_nhdsWithin _ (Ioi_mem_nhds hbx) filter_upwards [this] with y hy using hf hb hy.1 (le_of_lt hy.2) · rcases hxb.eq_or_lt with rfl | hxb · exact le_rfl simp only [ContinuousWithinAt] at h'x apply le_of_tendsto h'x have : s ∩ Iio b ∈ 𝓝[s] x := inter_mem_nhdsWithin _ (Iio_mem_nhds hxb) filter_upwards [this] with y hy exact hf hy.1 hb (le_of_lt hy.2)
lemma
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
MonotoneOn.insert_of_continuousWithinAt
null
MonotoneOn.countable_setOf_two_preimages [SecondCountableTopology α] (hf : MonotoneOn f s) : Set.Countable {c | ∃ x y, x ∈ s ∧ y ∈ s ∧ x < y ∧ f x = c ∧ f y = c} := by nontriviality α let t := {c | ∃ x, ∃ y, x ∈ s ∧ y ∈ s ∧ x < y ∧ f x = c ∧ f y = c} have : ∀ c ∈ t, ∃ x, ∃ y, x ∈ s ∧ y ∈ s ∧ x < y ∧ f x = c ∧ f y = c := fun c hc ↦ hc choose! x y hxs hys hxy hfx hfy using this let u := x '' t suffices H : Set.Countable (x '' t) by have : Set.InjOn x t := by intro c hc d hd hcd have : f (x c) = f (x d) := by simp [hcd] rwa [hfx _ hc, hfx _ hd] at this exact countable_of_injective_of_countable_image this H apply Set.PairwiseDisjoint.countable_of_Ioo (y := fun a ↦ y (f a)); swap · rintro a ⟨c, hc, rfl⟩ rw [hfx _ hc] exact hxy _ hc simp only [PairwiseDisjoint, Set.Pairwise, mem_image, onFun, forall_exists_index, and_imp, forall_apply_eq_imp_iff₂] intro c hc d hd hcd wlog H : c < d generalizing c d with h · apply (h d hd c hc hcd.symm ?_).symm have : c ≠ d := fun h ↦ hcd (congrArg x h) order simp only [disjoint_iff_forall_ne, mem_Ioo, ne_eq, and_imp] rintro a xca ayc b xda ayd rfl rw [hfx _ hc] at ayc have : x d ≤ y c := (xda.trans ayc).le have : f (x d) ≤ f (y c) := hf (hxs _ hd) (hys _ hc) this rw [hfx _ hd, hfy _ hc] at this exact not_le.2 H this
lemma
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
MonotoneOn.countable_setOf_two_preimages
If a function is monotone on a set in a second countable topological space, then there are only countably many points that have several preimages.
Monotone.countable_setOf_two_preimages [SecondCountableTopology α] (hf : Monotone f) : Set.Countable {c | ∃ x y, x < y ∧ f x = c ∧ f y = c} := by rw [← monotoneOn_univ] at hf simpa using hf.countable_setOf_two_preimages
lemma
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
Monotone.countable_setOf_two_preimages
If a function is monotone in a second countable topological space, then there are only countably many points that have several preimages.
AntitoneOn.countable_setOf_two_preimages [SecondCountableTopology α] (hf : AntitoneOn f s) : Set.Countable {c | ∃ x y, x ∈ s ∧ y ∈ s ∧ x < y ∧ f x = c ∧ f y = c} := (MonotoneOn.countable_setOf_two_preimages hf.dual_right :)
lemma
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
AntitoneOn.countable_setOf_two_preimages
If a function is antitone on a set in a second countable topological space, then there are only countably many points that have several preimages.
Antitone.countable_setOf_two_preimages [SecondCountableTopology α] (hf : Antitone f) : Set.Countable {c | ∃ x y, x < y ∧ f x = c ∧ f y = c} := (Monotone.countable_setOf_two_preimages hf.dual_right :)
lemma
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
Antitone.countable_setOf_two_preimages
If a function is antitone in a second countable topological space, then there are only countably many points that have several preimages.
MonotoneOn.countable_not_continuousWithinAt_Ioi (hf : MonotoneOn f s) : Set.Countable {x ∈ s | ¬ContinuousWithinAt f (s ∩ Ioi x) x} := by apply (countable_image_lt_image_Ioi_within s f).mono rintro x ⟨xs, hx : ¬ContinuousWithinAt f (s ∩ Ioi x) x⟩ dsimp only [mem_setOf_eq] contrapose! hx refine tendsto_order.2 ⟨fun m hm => ?_, fun u hu => ?_⟩ · filter_upwards [@self_mem_nhdsWithin _ _ x (s ∩ Ioi x)] with y hy exact hm.trans_le (hf xs hy.1 (le_of_lt hy.2)) rcases hx xs u hu with ⟨v, vs, xv, fvu⟩ have : s ∩ Ioo x v ∈ 𝓝[s ∩ Ioi x] x := by simp [nhdsWithin_inter, mem_inf_of_left, self_mem_nhdsWithin, mem_inf_of_right, Ioo_mem_nhdsGT xv] filter_upwards [this] with y hy exact (hf hy.1 vs hy.2.2.le).trans_lt fvu
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
MonotoneOn.countable_not_continuousWithinAt_Ioi
In a second countable space, the set of points where a monotone function is not right-continuous within a set is at most countable. Superseded by `MonotoneOn.countable_not_continuousWithinAt` which gives the two-sided version.
MonotoneOn.countable_not_continuousWithinAt_Iio (hf : MonotoneOn f s) : Set.Countable {x ∈ s | ¬ContinuousWithinAt f (s ∩ Iio x) x} := hf.dual.countable_not_continuousWithinAt_Ioi
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
MonotoneOn.countable_not_continuousWithinAt_Iio
In a second countable space, the set of points where a monotone function is not left-continuous within a set is at most countable. Superseded by `MonotoneOn.countable_not_continuousWithinAt` which gives the two-sided version.
MonotoneOn.countable_not_continuousWithinAt (hf : MonotoneOn f s) : Set.Countable {x ∈ s | ¬ContinuousWithinAt f s x} := by apply (hf.countable_not_continuousWithinAt_Ioi.union hf.countable_not_continuousWithinAt_Iio).mono refine compl_subset_compl.1 ?_ simp only [compl_union] rintro x ⟨hx, h'x⟩ simp only [mem_compl_iff, mem_setOf_eq, not_and, not_not] at hx h'x ⊢ intro xs exact continuousWithinAt_iff_continuous_left'_right'.2 ⟨h'x xs, hx xs⟩
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
MonotoneOn.countable_not_continuousWithinAt
In a second countable space, the set of points where a monotone function is not continuous within a set is at most countable.
Monotone.countable_not_continuousAt (hf : Monotone f) : Set.Countable {x | ¬ContinuousAt f x} := by simpa [continuousWithinAt_univ] using (hf.monotoneOn univ).countable_not_continuousWithinAt
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
Monotone.countable_not_continuousAt
In a second countable space, the set of points where a monotone function is not continuous is at most countable.
_root_.AntitoneOn.countable_not_continuousWithinAt {s : Set α} (hf : AntitoneOn f s) : Set.Countable {x ∈ s | ¬ContinuousWithinAt f s x} := hf.dual_right.countable_not_continuousWithinAt
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
_root_.AntitoneOn.countable_not_continuousWithinAt
In a second countable space, the set of points where an antitone function is not continuous within a set is at most countable.
Antitone.countable_not_continuousAt (hf : Antitone f) : Set.Countable {x | ¬ContinuousAt f x} := hf.dual_right.countable_not_continuousAt
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
Antitone.countable_not_continuousAt
In a second countable space, the set of points where an antitone function is not continuous is at most countable.
MonotoneOn.map_csSup_of_continuousWithinAt {f : α → β} {A : Set α} (Cf : ContinuousWithinAt f A (sSup A)) (Mf : MonotoneOn f A) (A_nonemp : A.Nonempty) (A_bdd : BddAbove A := by bddDefault) : f (sSup A) = sSup (f '' A) := .symm <| ((isLUB_csSup A_nonemp A_bdd).isLUB_of_tendsto Mf A_nonemp <| Cf.mono_left fun ⦃_⦄ a ↦ a).csSup_eq (A_nonemp.image f)
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
MonotoneOn.map_csSup_of_continuousWithinAt
A monotone function continuous at the supremum of a nonempty set sends this supremum to the supremum of the image of this set.
Monotone.map_csSup_of_continuousAt {f : α → β} {A : Set α} (Cf : ContinuousAt f (sSup A)) (Mf : Monotone f) (A_nonemp : A.Nonempty) (A_bdd : BddAbove A := by bddDefault) : f (sSup A) = sSup (f '' A) := MonotoneOn.map_csSup_of_continuousWithinAt Cf.continuousWithinAt (Mf.monotoneOn _) A_nonemp A_bdd
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
Monotone.map_csSup_of_continuousAt
A monotone function continuous at the supremum of a nonempty set sends this supremum to the supremum of the image of this set.
Monotone.map_ciSup_of_continuousAt {ι : Sort*} [Nonempty ι] {f : α → β} {g : ι → α} (Cf : ContinuousAt f (iSup g)) (Mf : Monotone f) (bdd : BddAbove (range g) := by bddDefault) : f (⨆ i, g i) = ⨆ i, f (g i) := by rw [iSup, Monotone.map_csSup_of_continuousAt Cf Mf (range_nonempty g) bdd, ← range_comp, iSup, comp_def]
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
Monotone.map_ciSup_of_continuousAt
A monotone function continuous at the indexed supremum over a nonempty `Sort` sends this indexed supremum to the indexed supremum of the composition.
MonotoneOn.map_csInf_of_continuousWithinAt {f : α → β} {A : Set α} (Cf : ContinuousWithinAt f A (sInf A)) (Mf : MonotoneOn f A) (A_nonemp : A.Nonempty) (A_bdd : BddBelow A := by bddDefault) : f (sInf A) = sInf (f '' A) := MonotoneOn.map_csSup_of_continuousWithinAt (α := αᵒᵈ) (β := βᵒᵈ) Cf Mf.dual A_nonemp A_bdd
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
MonotoneOn.map_csInf_of_continuousWithinAt
A monotone function continuous at the infimum of a nonempty set sends this infimum to the infimum of the image of this set.
Monotone.map_csInf_of_continuousAt {f : α → β} {A : Set α} (Cf : ContinuousAt f (sInf A)) (Mf : Monotone f) (A_nonemp : A.Nonempty) (A_bdd : BddBelow A := by bddDefault) : f (sInf A) = sInf (f '' A) := Monotone.map_csSup_of_continuousAt (α := αᵒᵈ) (β := βᵒᵈ) Cf Mf.dual A_nonemp A_bdd
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
Monotone.map_csInf_of_continuousAt
A monotone function continuous at the infimum of a nonempty set sends this infimum to the infimum of the image of this set.
Monotone.map_ciInf_of_continuousAt {ι : Sort*} [Nonempty ι] {f : α → β} {g : ι → α} (Cf : ContinuousAt f (iInf g)) (Mf : Monotone f) (bdd : BddBelow (range g) := by bddDefault) : f (⨅ i, g i) = ⨅ i, f (g i) := by rw [iInf, Monotone.map_csInf_of_continuousAt Cf Mf (range_nonempty g) bdd, ← range_comp, iInf, comp_def]
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
Monotone.map_ciInf_of_continuousAt
A monotone function continuous at the indexed infimum over a nonempty `Sort` sends this indexed infimum to the indexed infimum of the composition.
AntitoneOn.map_csInf_of_continuousWithinAt {f : α → β} {A : Set α} (Cf : ContinuousWithinAt f A (sInf A)) (Af : AntitoneOn f A) (A_nonemp : A.Nonempty) (A_bdd : BddBelow A := by bddDefault) : f (sInf A) = sSup (f '' A) := MonotoneOn.map_csInf_of_continuousWithinAt (β := βᵒᵈ) Cf Af.dual_right A_nonemp A_bdd
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
AntitoneOn.map_csInf_of_continuousWithinAt
An antitone function continuous at the infimum of a nonempty set sends this infimum to the supremum of the image of this set.
Antitone.map_csInf_of_continuousAt {f : α → β} {A : Set α} (Cf : ContinuousAt f (sInf A)) (Af : Antitone f) (A_nonemp : A.Nonempty) (A_bdd : BddBelow A := by bddDefault) : f (sInf A) = sSup (f '' A) := Monotone.map_csInf_of_continuousAt (β := βᵒᵈ) Cf Af.dual_right A_nonemp A_bdd
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
Antitone.map_csInf_of_continuousAt
An antitone function continuous at the infimum of a nonempty set sends this infimum to the supremum of the image of this set.
Antitone.map_ciInf_of_continuousAt {ι : Sort*} [Nonempty ι] {f : α → β} {g : ι → α} (Cf : ContinuousAt f (iInf g)) (Af : Antitone f) (bdd : BddBelow (range g) := by bddDefault) : f (⨅ i, g i) = ⨆ i, f (g i) := by rw [iInf, Antitone.map_csInf_of_continuousAt Cf Af (range_nonempty g) bdd, ← range_comp, iSup, comp_def]
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
Antitone.map_ciInf_of_continuousAt
An antitone function continuous at the indexed infimum over a nonempty `Sort` sends this indexed infimum to the indexed supremum of the composition.
AntitoneOn.map_csSup_of_continuousWithinAt {f : α → β} {A : Set α} (Cf : ContinuousWithinAt f A (sSup A)) (Af : AntitoneOn f A) (A_nonemp : A.Nonempty) (A_bdd : BddAbove A := by bddDefault) : f (sSup A) = sInf (f '' A) := MonotoneOn.map_csSup_of_continuousWithinAt (β := βᵒᵈ) Cf Af.dual_right A_nonemp A_bdd
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
AntitoneOn.map_csSup_of_continuousWithinAt
An antitone function continuous at the supremum of a nonempty set sends this supremum to the infimum of the image of this set.
Antitone.map_csSup_of_continuousAt {f : α → β} {A : Set α} (Cf : ContinuousAt f (sSup A)) (Af : Antitone f) (A_nonemp : A.Nonempty) (A_bdd : BddAbove A := by bddDefault) : f (sSup A) = sInf (f '' A) := Monotone.map_csSup_of_continuousAt (β := βᵒᵈ) Cf Af.dual_right A_nonemp A_bdd
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
Antitone.map_csSup_of_continuousAt
An antitone function continuous at the supremum of a nonempty set sends this supremum to the infimum of the image of this set.
Antitone.map_ciSup_of_continuousAt {ι : Sort*} [Nonempty ι] {f : α → β} {g : ι → α} (Cf : ContinuousAt f (iSup g)) (Af : Antitone f) (bdd : BddAbove (range g) := by bddDefault) : f (⨆ i, g i) = ⨅ i, f (g i) := by rw [iSup, Antitone.map_csSup_of_continuousAt Cf Af (range_nonempty g) bdd, ← range_comp, iInf, comp_def]
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
Antitone.map_ciSup_of_continuousAt
An antitone function continuous at the indexed supremum over a nonempty `Sort` sends this indexed supremum to the indexed infimum of the composition.
sSup_mem_closure {s : Set α} (hs : s.Nonempty) : sSup s ∈ closure s := (isLUB_sSup s).mem_closure hs
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
sSup_mem_closure
null
sInf_mem_closure {s : Set α} (hs : s.Nonempty) : sInf s ∈ closure s := (isGLB_sInf s).mem_closure hs
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
sInf_mem_closure
null
IsClosed.sSup_mem {s : Set α} (hs : s.Nonempty) (hc : IsClosed s) : sSup s ∈ s := (isLUB_sSup s).mem_of_isClosed hs hc
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
IsClosed.sSup_mem
null
IsClosed.sInf_mem {s : Set α} (hs : s.Nonempty) (hc : IsClosed s) : sInf s ∈ s := (isGLB_sInf s).mem_of_isClosed hs hc
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
IsClosed.sInf_mem
null
MonotoneOn.map_sSup_of_continuousWithinAt {f : α → β} {s : Set α} (Cf : ContinuousWithinAt f s (sSup s)) (Mf : MonotoneOn f s) (fbot : f ⊥ = ⊥) : f (sSup s) = sSup (f '' s) := by rcases s.eq_empty_or_nonempty with h | h · simp [h, fbot] · exact Mf.map_csSup_of_continuousWithinAt Cf h
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
MonotoneOn.map_sSup_of_continuousWithinAt
A monotone function `f` sending `bot` to `bot` and continuous at the supremum of a set sends this supremum to the supremum of the image of this set.
Monotone.map_sSup_of_continuousAt {f : α → β} {s : Set α} (Cf : ContinuousAt f (sSup s)) (Mf : Monotone f) (fbot : f ⊥ = ⊥) : f (sSup s) = sSup (f '' s) := MonotoneOn.map_sSup_of_continuousWithinAt Cf.continuousWithinAt (Mf.monotoneOn _) fbot
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
Monotone.map_sSup_of_continuousAt
A monotone function `f` sending `bot` to `bot` and continuous at the supremum of a set sends this supremum to the supremum of the image of this set.
Monotone.map_iSup_of_continuousAt {ι : Sort*} {f : α → β} {g : ι → α} (Cf : ContinuousAt f (iSup g)) (Mf : Monotone f) (fbot : f ⊥ = ⊥) : f (⨆ i, g i) = ⨆ i, f (g i) := by rw [iSup, Mf.map_sSup_of_continuousAt Cf fbot, ← range_comp, iSup, comp_def]
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
Monotone.map_iSup_of_continuousAt
If a monotone function sending `bot` to `bot` is continuous at the indexed supremum over a `Sort`, then it sends this indexed supremum to the indexed supremum of the composition.
MonotoneOn.map_sInf_of_continuousWithinAt {f : α → β} {s : Set α} (Cf : ContinuousWithinAt f s (sInf s)) (Mf : MonotoneOn f s) (ftop : f ⊤ = ⊤) : f (sInf s) = sInf (f '' s) := MonotoneOn.map_sSup_of_continuousWithinAt (α := αᵒᵈ) (β := βᵒᵈ) Cf Mf.dual ftop
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
MonotoneOn.map_sInf_of_continuousWithinAt
A monotone function `f` sending `top` to `top` and continuous at the infimum of a set sends this infimum to the infimum of the image of this set.
Monotone.map_sInf_of_continuousAt {f : α → β} {s : Set α} (Cf : ContinuousAt f (sInf s)) (Mf : Monotone f) (ftop : f ⊤ = ⊤) : f (sInf s) = sInf (f '' s) := Monotone.map_sSup_of_continuousAt (α := αᵒᵈ) (β := βᵒᵈ) Cf Mf.dual ftop
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
Monotone.map_sInf_of_continuousAt
A monotone function `f` sending `top` to `top` and continuous at the infimum of a set sends this infimum to the infimum of the image of this set.
Monotone.map_iInf_of_continuousAt {ι : Sort*} {f : α → β} {g : ι → α} (Cf : ContinuousAt f (iInf g)) (Mf : Monotone f) (ftop : f ⊤ = ⊤) : f (iInf g) = iInf (f ∘ g) := Monotone.map_iSup_of_continuousAt (α := αᵒᵈ) (β := βᵒᵈ) Cf Mf.dual ftop
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
Monotone.map_iInf_of_continuousAt
If a monotone function sending `top` to `top` is continuous at the indexed infimum over a `Sort`, then it sends this indexed infimum to the indexed infimum of the composition.
AntitoneOn.map_sSup_of_continuousWithinAt {f : α → β} {s : Set α} (Cf : ContinuousWithinAt f s (sSup s)) (Af : AntitoneOn f s) (fbot : f ⊥ = ⊤) : f (sSup s) = sInf (f '' s) := MonotoneOn.map_sSup_of_continuousWithinAt (show ContinuousWithinAt (OrderDual.toDual ∘ f) s (sSup s) from Cf) Af fbot
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
AntitoneOn.map_sSup_of_continuousWithinAt
An antitone function `f` sending `bot` to `top` and continuous at the supremum of a set sends this supremum to the infimum of the image of this set.
Antitone.map_sSup_of_continuousAt {f : α → β} {s : Set α} (Cf : ContinuousAt f (sSup s)) (Af : Antitone f) (fbot : f ⊥ = ⊤) : f (sSup s) = sInf (f '' s) := Monotone.map_sSup_of_continuousAt (show ContinuousAt (OrderDual.toDual ∘ f) (sSup s) from Cf) Af fbot
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
Antitone.map_sSup_of_continuousAt
An antitone function `f` sending `bot` to `top` and continuous at the supremum of a set sends this supremum to the infimum of the image of this set.
Antitone.map_iSup_of_continuousAt {ι : Sort*} {f : α → β} {g : ι → α} (Cf : ContinuousAt f (iSup g)) (Af : Antitone f) (fbot : f ⊥ = ⊤) : f (⨆ i, g i) = ⨅ i, f (g i) := Monotone.map_iSup_of_continuousAt (show ContinuousAt (OrderDual.toDual ∘ f) (iSup g) from Cf) Af fbot
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
Antitone.map_iSup_of_continuousAt
An antitone function sending `bot` to `top` is continuous at the indexed supremum over a `Sort`, then it sends this indexed supremum to the indexed supremum of the composition.
AntitoneOn.map_sInf_of_continuousWithinAt {f : α → β} {s : Set α} (Cf : ContinuousWithinAt f s (sInf s)) (Af : AntitoneOn f s) (ftop : f ⊤ = ⊥) : f (sInf s) = sSup (f '' s) := MonotoneOn.map_sInf_of_continuousWithinAt (show ContinuousWithinAt (OrderDual.toDual ∘ f) s (sInf s) from Cf) Af ftop
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
AntitoneOn.map_sInf_of_continuousWithinAt
An antitone function `f` sending `top` to `bot` and continuous at the infimum of a set sends this infimum to the supremum of the image of this set.
Antitone.map_sInf_of_continuousAt {f : α → β} {s : Set α} (Cf : ContinuousAt f (sInf s)) (Af : Antitone f) (ftop : f ⊤ = ⊥) : f (sInf s) = sSup (f '' s) := Monotone.map_sInf_of_continuousAt (show ContinuousAt (OrderDual.toDual ∘ f) (sInf s) from Cf) Af ftop
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
Antitone.map_sInf_of_continuousAt
An antitone function `f` sending `top` to `bot` and continuous at the infimum of a set sends this infimum to the supremum of the image of this set.
Antitone.map_iInf_of_continuousAt {ι : Sort*} {f : α → β} {g : ι → α} (Cf : ContinuousAt f (iInf g)) (Af : Antitone f) (ftop : f ⊤ = ⊥) : f (iInf g) = iSup (f ∘ g) := Monotone.map_iInf_of_continuousAt (show ContinuousAt (OrderDual.toDual ∘ f) (iInf g) from Cf) Af ftop
theorem
Topology
[ "Mathlib.Tactic.Order", "Mathlib.Topology.Order.IsLUB" ]
Mathlib/Topology/Order/Monotone.lean
Antitone.map_iInf_of_continuousAt
If an antitone function sending `top` to `bot` is continuous at the indexed infimum over a `Sort`, then it sends this indexed infimum to the indexed supremum of the composition.