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import Mathlib.Computability.Encoding import Mathlib.Logic.Small.List import Mathlib.ModelTheory.Syntax import Mathlib.SetTheory.Cardinal.Ordinal #align_import model_theory.encoding from "leanprover-community/mathlib"@"91288e351d51b3f0748f0a38faa7613fb0ae2ada" universe u v w u' v' namespace FirstOrder namespace Language variable {L : Language.{u, v}} variable {M : Type w} {N P : Type*} [L.Structure M] [L.Structure N] [L.Structure P] variable {α : Type u'} {β : Type v'} open FirstOrder Cardinal open Computability List Structure Cardinal Fin namespace Term def listEncode : L.Term α → List (Sum α (Σi, L.Functions i)) | var i => [Sum.inl i] | func f ts => Sum.inr (⟨_, f⟩ : Σi, L.Functions i)::(List.finRange _).bind fun i => (ts i).listEncode #align first_order.language.term.list_encode FirstOrder.Language.Term.listEncode def listDecode : List (Sum α (Σi, L.Functions i)) → List (Option (L.Term α)) | [] => [] | Sum.inl a::l => some (var a)::listDecode l | Sum.inr ⟨n, f⟩::l => if h : ∀ i : Fin n, ((listDecode l).get? i).join.isSome then (func f fun i => Option.get _ (h i))::(listDecode l).drop n else [none] #align first_order.language.term.list_decode FirstOrder.Language.Term.listDecode theorem listDecode_encode_list (l : List (L.Term α)) : listDecode (l.bind listEncode) = l.map Option.some := by suffices h : ∀ (t : L.Term α) (l : List (Sum α (Σi, L.Functions i))), listDecode (t.listEncode ++ l) = some t::listDecode l by induction' l with t l lih · rfl · rw [cons_bind, h t (l.bind listEncode), lih, List.map] intro t induction' t with a n f ts ih <;> intro l · rw [listEncode, singleton_append, listDecode] · rw [listEncode, cons_append, listDecode] have h : listDecode (((finRange n).bind fun i : Fin n => (ts i).listEncode) ++ l) = (finRange n).map (Option.some ∘ ts) ++ listDecode l := by induction' finRange n with i l' l'ih · rfl · rw [cons_bind, List.append_assoc, ih, map_cons, l'ih, cons_append, Function.comp] have h' : ∀ i : Fin n, (listDecode (((finRange n).bind fun i : Fin n => (ts i).listEncode) ++ l)).get? ↑i = some (some (ts i)) := by intro i rw [h, get?_append, get?_map] · simp only [Option.map_eq_some', Function.comp_apply, get?_eq_some] refine ⟨i, ⟨lt_of_lt_of_le i.2 (ge_of_eq (length_finRange _)), ?_⟩, rfl⟩ rw [get_finRange, Fin.eta] · refine lt_of_lt_of_le i.2 ?_ simp refine (dif_pos fun i => Option.isSome_iff_exists.2 ⟨ts i, ?_⟩).trans ?_ · rw [Option.join_eq_some, h'] refine congr (congr rfl (congr rfl (congr rfl (funext fun i => Option.get_of_mem _ ?_)))) ?_ · simp [h'] · rw [h, drop_left'] rw [length_map, length_finRange] #align first_order.language.term.list_decode_encode_list FirstOrder.Language.Term.listDecode_encode_list @[simps] protected def encoding : Encoding (L.Term α) where Γ := Sum α (Σi, L.Functions i) encode := listEncode decode l := (listDecode l).head?.join decode_encode t := by have h := listDecode_encode_list [t] rw [bind_singleton] at h simp only [h, Option.join, head?, List.map, Option.some_bind, id] #align first_order.language.term.encoding FirstOrder.Language.Term.encoding theorem listEncode_injective : Function.Injective (listEncode : L.Term α → List (Sum α (Σi, L.Functions i))) := Term.encoding.encode_injective #align first_order.language.term.list_encode_injective FirstOrder.Language.Term.listEncode_injective theorem card_le : #(L.Term α) ≤ max ℵ₀ #(Sum α (Σi, L.Functions i)) := lift_le.1 (_root_.trans Term.encoding.card_le_card_list (lift_le.2 (mk_list_le_max _))) #align first_order.language.term.card_le FirstOrder.Language.Term.card_le
Mathlib/ModelTheory/Encoding.lean
122
151
theorem card_sigma : #(Σn, L.Term (Sum α (Fin n))) = max ℵ₀ #(Sum α (Σi, L.Functions i)) := by
refine le_antisymm ?_ ?_ · rw [mk_sigma] refine (sum_le_iSup_lift _).trans ?_ rw [mk_nat, lift_aleph0, mul_eq_max_of_aleph0_le_left le_rfl, max_le_iff, ciSup_le_iff' (bddAbove_range _)] · refine ⟨le_max_left _ _, fun i => card_le.trans ?_⟩ refine max_le (le_max_left _ _) ?_ rw [← add_eq_max le_rfl, mk_sum, mk_sum, mk_sum, add_comm (Cardinal.lift #α), lift_add, add_assoc, lift_lift, lift_lift, mk_fin, lift_natCast] exact add_le_add_right (nat_lt_aleph0 _).le _ · rw [← one_le_iff_ne_zero] refine _root_.trans ?_ (le_ciSup (bddAbove_range _) 1) rw [one_le_iff_ne_zero, mk_ne_zero_iff] exact ⟨var (Sum.inr 0)⟩ · rw [max_le_iff, ← infinite_iff] refine ⟨Infinite.of_injective (fun i => ⟨i + 1, var (Sum.inr i)⟩) fun i j ij => ?_, ?_⟩ · cases ij rfl · rw [Cardinal.le_def] refine ⟨⟨Sum.elim (fun i => ⟨0, var (Sum.inl i)⟩) fun F => ⟨1, func F.2 fun _ => var (Sum.inr 0)⟩, ?_⟩⟩ rintro (a | a) (b | b) h · simp only [Sum.elim_inl, Sigma.mk.inj_iff, heq_eq_eq, var.injEq, Sum.inl.injEq, true_and] at h rw [h] · simp only [Sum.elim_inl, Sum.elim_inr, Sigma.mk.inj_iff, false_and] at h · simp only [Sum.elim_inr, Sum.elim_inl, Sigma.mk.inj_iff, false_and] at h · simp only [Sum.elim_inr, Sigma.mk.inj_iff, heq_eq_eq, func.injEq, true_and] at h rw [Sigma.ext_iff.2 ⟨h.1, h.2.1⟩]
import Mathlib.Data.Set.Basic open Function universe u v namespace Set section Subsingleton variable {α : Type u} {a : α} {s t : Set α} protected def Subsingleton (s : Set α) : Prop := ∀ ⦃x⦄ (_ : x ∈ s) ⦃y⦄ (_ : y ∈ s), x = y #align set.subsingleton Set.Subsingleton theorem Subsingleton.anti (ht : t.Subsingleton) (hst : s ⊆ t) : s.Subsingleton := fun _ hx _ hy => ht (hst hx) (hst hy) #align set.subsingleton.anti Set.Subsingleton.anti theorem Subsingleton.eq_singleton_of_mem (hs : s.Subsingleton) {x : α} (hx : x ∈ s) : s = {x} := ext fun _ => ⟨fun hy => hs hx hy ▸ mem_singleton _, fun hy => (eq_of_mem_singleton hy).symm ▸ hx⟩ #align set.subsingleton.eq_singleton_of_mem Set.Subsingleton.eq_singleton_of_mem @[simp] theorem subsingleton_empty : (∅ : Set α).Subsingleton := fun _ => False.elim #align set.subsingleton_empty Set.subsingleton_empty @[simp] theorem subsingleton_singleton {a} : ({a} : Set α).Subsingleton := fun _ hx _ hy => (eq_of_mem_singleton hx).symm ▸ (eq_of_mem_singleton hy).symm ▸ rfl #align set.subsingleton_singleton Set.subsingleton_singleton theorem subsingleton_of_subset_singleton (h : s ⊆ {a}) : s.Subsingleton := subsingleton_singleton.anti h #align set.subsingleton_of_subset_singleton Set.subsingleton_of_subset_singleton theorem subsingleton_of_forall_eq (a : α) (h : ∀ b ∈ s, b = a) : s.Subsingleton := fun _ hb _ hc => (h _ hb).trans (h _ hc).symm #align set.subsingleton_of_forall_eq Set.subsingleton_of_forall_eq theorem subsingleton_iff_singleton {x} (hx : x ∈ s) : s.Subsingleton ↔ s = {x} := ⟨fun h => h.eq_singleton_of_mem hx, fun h => h.symm ▸ subsingleton_singleton⟩ #align set.subsingleton_iff_singleton Set.subsingleton_iff_singleton theorem Subsingleton.eq_empty_or_singleton (hs : s.Subsingleton) : s = ∅ ∨ ∃ x, s = {x} := s.eq_empty_or_nonempty.elim Or.inl fun ⟨x, hx⟩ => Or.inr ⟨x, hs.eq_singleton_of_mem hx⟩ #align set.subsingleton.eq_empty_or_singleton Set.Subsingleton.eq_empty_or_singleton theorem Subsingleton.induction_on {p : Set α → Prop} (hs : s.Subsingleton) (he : p ∅) (h₁ : ∀ x, p {x}) : p s := by rcases hs.eq_empty_or_singleton with (rfl | ⟨x, rfl⟩) exacts [he, h₁ _] #align set.subsingleton.induction_on Set.Subsingleton.induction_on theorem subsingleton_univ [Subsingleton α] : (univ : Set α).Subsingleton := fun x _ y _ => Subsingleton.elim x y #align set.subsingleton_univ Set.subsingleton_univ theorem subsingleton_of_univ_subsingleton (h : (univ : Set α).Subsingleton) : Subsingleton α := ⟨fun a b => h (mem_univ a) (mem_univ b)⟩ #align set.subsingleton_of_univ_subsingleton Set.subsingleton_of_univ_subsingleton @[simp] theorem subsingleton_univ_iff : (univ : Set α).Subsingleton ↔ Subsingleton α := ⟨subsingleton_of_univ_subsingleton, fun h => @subsingleton_univ _ h⟩ #align set.subsingleton_univ_iff Set.subsingleton_univ_iff theorem subsingleton_of_subsingleton [Subsingleton α] {s : Set α} : Set.Subsingleton s := subsingleton_univ.anti (subset_univ s) #align set.subsingleton_of_subsingleton Set.subsingleton_of_subsingleton theorem subsingleton_isTop (α : Type*) [PartialOrder α] : Set.Subsingleton { x : α | IsTop x } := fun x hx _ hy => hx.isMax.eq_of_le (hy x) #align set.subsingleton_is_top Set.subsingleton_isTop theorem subsingleton_isBot (α : Type*) [PartialOrder α] : Set.Subsingleton { x : α | IsBot x } := fun x hx _ hy => hx.isMin.eq_of_ge (hy x) #align set.subsingleton_is_bot Set.subsingleton_isBot
Mathlib/Data/Set/Subsingleton.lean
99
104
theorem exists_eq_singleton_iff_nonempty_subsingleton : (∃ a : α, s = {a}) ↔ s.Nonempty ∧ s.Subsingleton := by
refine ⟨?_, fun h => ?_⟩ · rintro ⟨a, rfl⟩ exact ⟨singleton_nonempty a, subsingleton_singleton⟩ · exact h.2.eq_empty_or_singleton.resolve_left h.1.ne_empty
import Mathlib.Dynamics.Ergodic.MeasurePreserving import Mathlib.LinearAlgebra.Determinant import Mathlib.LinearAlgebra.Matrix.Diagonal import Mathlib.LinearAlgebra.Matrix.Transvection import Mathlib.MeasureTheory.Group.LIntegral import Mathlib.MeasureTheory.Integral.Marginal import Mathlib.MeasureTheory.Measure.Stieltjes import Mathlib.MeasureTheory.Measure.Haar.OfBasis #align_import measure_theory.measure.lebesgue.basic from "leanprover-community/mathlib"@"fd5edc43dc4f10b85abfe544b88f82cf13c5f844" assert_not_exists MeasureTheory.integral noncomputable section open scoped Classical open Set Filter MeasureTheory MeasureTheory.Measure TopologicalSpace open ENNReal (ofReal) open scoped ENNReal NNReal Topology namespace Real variable {ι : Type*} [Fintype ι] theorem volume_eq_stieltjes_id : (volume : Measure ℝ) = StieltjesFunction.id.measure := by haveI : IsAddLeftInvariant StieltjesFunction.id.measure := ⟨fun a => Eq.symm <| Real.measure_ext_Ioo_rat fun p q => by simp only [Measure.map_apply (measurable_const_add a) measurableSet_Ioo, sub_sub_sub_cancel_right, StieltjesFunction.measure_Ioo, StieltjesFunction.id_leftLim, StieltjesFunction.id_apply, id, preimage_const_add_Ioo]⟩ have A : StieltjesFunction.id.measure (stdOrthonormalBasis ℝ ℝ).toBasis.parallelepiped = 1 := by change StieltjesFunction.id.measure (parallelepiped (stdOrthonormalBasis ℝ ℝ)) = 1 rcases parallelepiped_orthonormalBasis_one_dim (stdOrthonormalBasis ℝ ℝ) with (H | H) <;> simp only [H, StieltjesFunction.measure_Icc, StieltjesFunction.id_apply, id, tsub_zero, StieltjesFunction.id_leftLim, sub_neg_eq_add, zero_add, ENNReal.ofReal_one] conv_rhs => rw [addHaarMeasure_unique StieltjesFunction.id.measure (stdOrthonormalBasis ℝ ℝ).toBasis.parallelepiped, A] simp only [volume, Basis.addHaar, one_smul] #align real.volume_eq_stieltjes_id Real.volume_eq_stieltjes_id theorem volume_val (s) : volume s = StieltjesFunction.id.measure s := by simp [volume_eq_stieltjes_id] #align real.volume_val Real.volume_val @[simp] theorem volume_Ico {a b : ℝ} : volume (Ico a b) = ofReal (b - a) := by simp [volume_val] #align real.volume_Ico Real.volume_Ico @[simp] theorem volume_Icc {a b : ℝ} : volume (Icc a b) = ofReal (b - a) := by simp [volume_val] #align real.volume_Icc Real.volume_Icc @[simp] theorem volume_Ioo {a b : ℝ} : volume (Ioo a b) = ofReal (b - a) := by simp [volume_val] #align real.volume_Ioo Real.volume_Ioo @[simp] theorem volume_Ioc {a b : ℝ} : volume (Ioc a b) = ofReal (b - a) := by simp [volume_val] #align real.volume_Ioc Real.volume_Ioc -- @[simp] -- Porting note (#10618): simp can prove this
Mathlib/MeasureTheory/Measure/Lebesgue/Basic.lean
96
96
theorem volume_singleton {a : ℝ} : volume ({a} : Set ℝ) = 0 := by
simp [volume_val]
import Mathlib.Algebra.Field.Subfield import Mathlib.Algebra.GroupWithZero.Divisibility import Mathlib.Topology.Algebra.GroupWithZero import Mathlib.Topology.Algebra.Ring.Basic import Mathlib.Topology.Order.LocalExtr #align_import topology.algebra.field from "leanprover-community/mathlib"@"c10e724be91096453ee3db13862b9fb9a992fef2" variable {K : Type*} [DivisionRing K] [TopologicalSpace K] theorem Filter.tendsto_cocompact_mul_left₀ [ContinuousMul K] {a : K} (ha : a ≠ 0) : Filter.Tendsto (fun x : K => a * x) (Filter.cocompact K) (Filter.cocompact K) := Filter.tendsto_cocompact_mul_left (inv_mul_cancel ha) #align filter.tendsto_cocompact_mul_left₀ Filter.tendsto_cocompact_mul_left₀ theorem Filter.tendsto_cocompact_mul_right₀ [ContinuousMul K] {a : K} (ha : a ≠ 0) : Filter.Tendsto (fun x : K => x * a) (Filter.cocompact K) (Filter.cocompact K) := Filter.tendsto_cocompact_mul_right (mul_inv_cancel ha) #align filter.tendsto_cocompact_mul_right₀ Filter.tendsto_cocompact_mul_right₀ variable (K) class TopologicalDivisionRing extends TopologicalRing K, HasContinuousInv₀ K : Prop #align topological_division_ring TopologicalDivisionRing section LocalExtr variable {α β : Type*} [TopologicalSpace α] [LinearOrderedSemifield β] {a : α} open Topology
Mathlib/Topology/Algebra/Field.lean
112
114
theorem IsLocalMin.inv {f : α → β} {a : α} (h1 : IsLocalMin f a) (h2 : ∀ᶠ z in 𝓝 a, 0 < f z) : IsLocalMax f⁻¹ a := by
filter_upwards [h1, h2] with z h3 h4 using(inv_le_inv h4 h2.self_of_nhds).mpr h3
import Mathlib.Algebra.BigOperators.Group.Finset import Mathlib.Algebra.Group.Commute.Hom import Mathlib.Data.Fintype.Card #align_import data.finset.noncomm_prod from "leanprover-community/mathlib"@"509de852e1de55e1efa8eacfa11df0823f26f226" variable {F ι α β γ : Type*} (f : α → β → β) (op : α → α → α) namespace Multiset def noncommFoldr (s : Multiset α) (comm : { x | x ∈ s }.Pairwise fun x y => ∀ b, f x (f y b) = f y (f x b)) (b : β) : β := s.attach.foldr (f ∘ Subtype.val) (fun ⟨_, hx⟩ ⟨_, hy⟩ => haveI : IsRefl α fun x y => ∀ b, f x (f y b) = f y (f x b) := ⟨fun _ _ => rfl⟩ comm.of_refl hx hy) b #align multiset.noncomm_foldr Multiset.noncommFoldr @[simp] theorem noncommFoldr_coe (l : List α) (comm) (b : β) : noncommFoldr f (l : Multiset α) comm b = l.foldr f b := by simp only [noncommFoldr, coe_foldr, coe_attach, List.attach, List.attachWith, Function.comp] rw [← List.foldr_map] simp [List.map_pmap] #align multiset.noncomm_foldr_coe Multiset.noncommFoldr_coe @[simp] theorem noncommFoldr_empty (h) (b : β) : noncommFoldr f (0 : Multiset α) h b = b := rfl #align multiset.noncomm_foldr_empty Multiset.noncommFoldr_empty
Mathlib/Data/Finset/NoncommProd.lean
64
67
theorem noncommFoldr_cons (s : Multiset α) (a : α) (h h') (b : β) : noncommFoldr f (a ::ₘ s) h b = f a (noncommFoldr f s h' b) := by
induction s using Quotient.inductionOn simp
import Mathlib.CategoryTheory.Balanced import Mathlib.CategoryTheory.Limits.EssentiallySmall import Mathlib.CategoryTheory.Limits.Opposites import Mathlib.CategoryTheory.Limits.Shapes.ZeroMorphisms import Mathlib.CategoryTheory.Subobject.Lattice import Mathlib.CategoryTheory.Subobject.WellPowered import Mathlib.Data.Set.Opposite import Mathlib.Data.Set.Subsingleton #align_import category_theory.generator from "leanprover-community/mathlib"@"f187f1074fa1857c94589cc653c786cadc4c35ff" universe w v₁ v₂ u₁ u₂ open CategoryTheory.Limits Opposite namespace CategoryTheory variable {C : Type u₁} [Category.{v₁} C] {D : Type u₂} [Category.{v₂} D] def IsSeparating (𝒢 : Set C) : Prop := ∀ ⦃X Y : C⦄ (f g : X ⟶ Y), (∀ G ∈ 𝒢, ∀ (h : G ⟶ X), h ≫ f = h ≫ g) → f = g #align category_theory.is_separating CategoryTheory.IsSeparating def IsCoseparating (𝒢 : Set C) : Prop := ∀ ⦃X Y : C⦄ (f g : X ⟶ Y), (∀ G ∈ 𝒢, ∀ (h : Y ⟶ G), f ≫ h = g ≫ h) → f = g #align category_theory.is_coseparating CategoryTheory.IsCoseparating def IsDetecting (𝒢 : Set C) : Prop := ∀ ⦃X Y : C⦄ (f : X ⟶ Y), (∀ G ∈ 𝒢, ∀ (h : G ⟶ Y), ∃! h' : G ⟶ X, h' ≫ f = h) → IsIso f #align category_theory.is_detecting CategoryTheory.IsDetecting def IsCodetecting (𝒢 : Set C) : Prop := ∀ ⦃X Y : C⦄ (f : X ⟶ Y), (∀ G ∈ 𝒢, ∀ (h : X ⟶ G), ∃! h' : Y ⟶ G, f ≫ h' = h) → IsIso f #align category_theory.is_codetecting CategoryTheory.IsCodetecting section Dual
Mathlib/CategoryTheory/Generator.lean
93
98
theorem isSeparating_op_iff (𝒢 : Set C) : IsSeparating 𝒢.op ↔ IsCoseparating 𝒢 := by
refine ⟨fun h𝒢 X Y f g hfg => ?_, fun h𝒢 X Y f g hfg => ?_⟩ · refine Quiver.Hom.op_inj (h𝒢 _ _ fun G hG h => Quiver.Hom.unop_inj ?_) simpa only [unop_comp, Quiver.Hom.unop_op] using hfg _ (Set.mem_op.1 hG) _ · refine Quiver.Hom.unop_inj (h𝒢 _ _ fun G hG h => Quiver.Hom.op_inj ?_) simpa only [op_comp, Quiver.Hom.op_unop] using hfg _ (Set.op_mem_op.2 hG) _
import Mathlib.Order.Interval.Set.Basic import Mathlib.Order.Hom.Set #align_import data.set.intervals.order_iso from "leanprover-community/mathlib"@"d012cd09a9b256d870751284dd6a29882b0be105" open Set namespace OrderIso section Preorder variable {α β : Type*} [Preorder α] [Preorder β] @[simp] theorem preimage_Iic (e : α ≃o β) (b : β) : e ⁻¹' Iic b = Iic (e.symm b) := by ext x simp [← e.le_iff_le] #align order_iso.preimage_Iic OrderIso.preimage_Iic @[simp] theorem preimage_Ici (e : α ≃o β) (b : β) : e ⁻¹' Ici b = Ici (e.symm b) := by ext x simp [← e.le_iff_le] #align order_iso.preimage_Ici OrderIso.preimage_Ici @[simp] theorem preimage_Iio (e : α ≃o β) (b : β) : e ⁻¹' Iio b = Iio (e.symm b) := by ext x simp [← e.lt_iff_lt] #align order_iso.preimage_Iio OrderIso.preimage_Iio @[simp] theorem preimage_Ioi (e : α ≃o β) (b : β) : e ⁻¹' Ioi b = Ioi (e.symm b) := by ext x simp [← e.lt_iff_lt] #align order_iso.preimage_Ioi OrderIso.preimage_Ioi @[simp] theorem preimage_Icc (e : α ≃o β) (a b : β) : e ⁻¹' Icc a b = Icc (e.symm a) (e.symm b) := by simp [← Ici_inter_Iic] #align order_iso.preimage_Icc OrderIso.preimage_Icc @[simp] theorem preimage_Ico (e : α ≃o β) (a b : β) : e ⁻¹' Ico a b = Ico (e.symm a) (e.symm b) := by simp [← Ici_inter_Iio] #align order_iso.preimage_Ico OrderIso.preimage_Ico @[simp] theorem preimage_Ioc (e : α ≃o β) (a b : β) : e ⁻¹' Ioc a b = Ioc (e.symm a) (e.symm b) := by simp [← Ioi_inter_Iic] #align order_iso.preimage_Ioc OrderIso.preimage_Ioc @[simp] theorem preimage_Ioo (e : α ≃o β) (a b : β) : e ⁻¹' Ioo a b = Ioo (e.symm a) (e.symm b) := by simp [← Ioi_inter_Iio] #align order_iso.preimage_Ioo OrderIso.preimage_Ioo @[simp] theorem image_Iic (e : α ≃o β) (a : α) : e '' Iic a = Iic (e a) := by rw [e.image_eq_preimage, e.symm.preimage_Iic, e.symm_symm] #align order_iso.image_Iic OrderIso.image_Iic @[simp] theorem image_Ici (e : α ≃o β) (a : α) : e '' Ici a = Ici (e a) := e.dual.image_Iic a #align order_iso.image_Ici OrderIso.image_Ici @[simp] theorem image_Iio (e : α ≃o β) (a : α) : e '' Iio a = Iio (e a) := by rw [e.image_eq_preimage, e.symm.preimage_Iio, e.symm_symm] #align order_iso.image_Iio OrderIso.image_Iio @[simp] theorem image_Ioi (e : α ≃o β) (a : α) : e '' Ioi a = Ioi (e a) := e.dual.image_Iio a #align order_iso.image_Ioi OrderIso.image_Ioi @[simp] theorem image_Ioo (e : α ≃o β) (a b : α) : e '' Ioo a b = Ioo (e a) (e b) := by rw [e.image_eq_preimage, e.symm.preimage_Ioo, e.symm_symm] #align order_iso.image_Ioo OrderIso.image_Ioo @[simp] theorem image_Ioc (e : α ≃o β) (a b : α) : e '' Ioc a b = Ioc (e a) (e b) := by rw [e.image_eq_preimage, e.symm.preimage_Ioc, e.symm_symm] #align order_iso.image_Ioc OrderIso.image_Ioc @[simp]
Mathlib/Order/Interval/Set/OrderIso.lean
98
99
theorem image_Ico (e : α ≃o β) (a b : α) : e '' Ico a b = Ico (e a) (e b) := by
rw [e.image_eq_preimage, e.symm.preimage_Ico, e.symm_symm]
import Mathlib.Analysis.InnerProductSpace.TwoDim import Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic #align_import geometry.euclidean.angle.oriented.basic from "leanprover-community/mathlib"@"f0c8bf9245297a541f468be517f1bde6195105e9" noncomputable section open FiniteDimensional Complex open scoped Real RealInnerProductSpace ComplexConjugate namespace Orientation attribute [local instance] Complex.finrank_real_complex_fact variable {V V' : Type*} variable [NormedAddCommGroup V] [NormedAddCommGroup V'] variable [InnerProductSpace ℝ V] [InnerProductSpace ℝ V'] variable [Fact (finrank ℝ V = 2)] [Fact (finrank ℝ V' = 2)] (o : Orientation ℝ V (Fin 2)) local notation "ω" => o.areaForm def oangle (x y : V) : Real.Angle := Complex.arg (o.kahler x y) #align orientation.oangle Orientation.oangle theorem continuousAt_oangle {x : V × V} (hx1 : x.1 ≠ 0) (hx2 : x.2 ≠ 0) : ContinuousAt (fun y : V × V => o.oangle y.1 y.2) x := by refine (Complex.continuousAt_arg_coe_angle ?_).comp ?_ · exact o.kahler_ne_zero hx1 hx2 exact ((continuous_ofReal.comp continuous_inner).add ((continuous_ofReal.comp o.areaForm'.continuous₂).mul continuous_const)).continuousAt #align orientation.continuous_at_oangle Orientation.continuousAt_oangle @[simp]
Mathlib/Geometry/Euclidean/Angle/Oriented/Basic.lean
68
68
theorem oangle_zero_left (x : V) : o.oangle 0 x = 0 := by
simp [oangle]
import Mathlib.Algebra.MonoidAlgebra.Degree import Mathlib.Algebra.Polynomial.Coeff import Mathlib.Algebra.Polynomial.Monomial import Mathlib.Data.Fintype.BigOperators import Mathlib.Data.Nat.WithBot import Mathlib.Data.Nat.Cast.WithTop import Mathlib.Data.Nat.SuccPred #align_import data.polynomial.degree.definitions from "leanprover-community/mathlib"@"808ea4ebfabeb599f21ec4ae87d6dc969597887f" -- Porting note: `Mathlib.Data.Nat.Cast.WithTop` should be imported for `Nat.cast_withBot`. set_option linter.uppercaseLean3 false noncomputable section open Finsupp Finset open Polynomial namespace Polynomial universe u v variable {R : Type u} {S : Type v} {a b c d : R} {n m : ℕ} section Semiring variable [Semiring R] {p q r : R[X]} def degree (p : R[X]) : WithBot ℕ := p.support.max #align polynomial.degree Polynomial.degree theorem supDegree_eq_degree (p : R[X]) : p.toFinsupp.supDegree WithBot.some = p.degree := max_eq_sup_coe theorem degree_lt_wf : WellFounded fun p q : R[X] => degree p < degree q := InvImage.wf degree wellFounded_lt #align polynomial.degree_lt_wf Polynomial.degree_lt_wf instance : WellFoundedRelation R[X] := ⟨_, degree_lt_wf⟩ def natDegree (p : R[X]) : ℕ := (degree p).unbot' 0 #align polynomial.nat_degree Polynomial.natDegree def leadingCoeff (p : R[X]) : R := coeff p (natDegree p) #align polynomial.leading_coeff Polynomial.leadingCoeff def Monic (p : R[X]) := leadingCoeff p = (1 : R) #align polynomial.monic Polynomial.Monic @[nontriviality] theorem monic_of_subsingleton [Subsingleton R] (p : R[X]) : Monic p := Subsingleton.elim _ _ #align polynomial.monic_of_subsingleton Polynomial.monic_of_subsingleton theorem Monic.def : Monic p ↔ leadingCoeff p = 1 := Iff.rfl #align polynomial.monic.def Polynomial.Monic.def instance Monic.decidable [DecidableEq R] : Decidable (Monic p) := by unfold Monic; infer_instance #align polynomial.monic.decidable Polynomial.Monic.decidable @[simp] theorem Monic.leadingCoeff {p : R[X]} (hp : p.Monic) : leadingCoeff p = 1 := hp #align polynomial.monic.leading_coeff Polynomial.Monic.leadingCoeff theorem Monic.coeff_natDegree {p : R[X]} (hp : p.Monic) : p.coeff p.natDegree = 1 := hp #align polynomial.monic.coeff_nat_degree Polynomial.Monic.coeff_natDegree @[simp] theorem degree_zero : degree (0 : R[X]) = ⊥ := rfl #align polynomial.degree_zero Polynomial.degree_zero @[simp] theorem natDegree_zero : natDegree (0 : R[X]) = 0 := rfl #align polynomial.nat_degree_zero Polynomial.natDegree_zero @[simp] theorem coeff_natDegree : coeff p (natDegree p) = leadingCoeff p := rfl #align polynomial.coeff_nat_degree Polynomial.coeff_natDegree @[simp] theorem degree_eq_bot : degree p = ⊥ ↔ p = 0 := ⟨fun h => support_eq_empty.1 (Finset.max_eq_bot.1 h), fun h => h.symm ▸ rfl⟩ #align polynomial.degree_eq_bot Polynomial.degree_eq_bot @[nontriviality] theorem degree_of_subsingleton [Subsingleton R] : degree p = ⊥ := by rw [Subsingleton.elim p 0, degree_zero] #align polynomial.degree_of_subsingleton Polynomial.degree_of_subsingleton @[nontriviality]
Mathlib/Algebra/Polynomial/Degree/Definitions.lean
128
129
theorem natDegree_of_subsingleton [Subsingleton R] : natDegree p = 0 := by
rw [Subsingleton.elim p 0, natDegree_zero]
import Mathlib.Algebra.GCDMonoid.Basic import Mathlib.RingTheory.IntegrallyClosed import Mathlib.RingTheory.Polynomial.Eisenstein.Basic #align_import algebra.gcd_monoid.integrally_closed from "leanprover-community/mathlib"@"2032a878972d5672e7c27c957e7a6e297b044973" open scoped Polynomial variable {R A : Type*} [CommRing R] [IsDomain R] [CommRing A] [Algebra R A]
Mathlib/Algebra/GCDMonoid/IntegrallyClosed.lean
23
30
theorem IsLocalization.surj_of_gcd_domain [GCDMonoid R] (M : Submonoid R) [IsLocalization M A] (z : A) : ∃ a b : R, IsUnit (gcd a b) ∧ z * algebraMap R A b = algebraMap R A a := by
obtain ⟨x, ⟨y, hy⟩, rfl⟩ := IsLocalization.mk'_surjective M z obtain ⟨x', y', hx', hy', hu⟩ := extract_gcd x y use x', y', hu rw [mul_comm, IsLocalization.mul_mk'_eq_mk'_of_mul] convert IsLocalization.mk'_mul_cancel_left (M := M) (S := A) _ _ using 2 rw [Subtype.coe_mk, hy', ← mul_comm y', mul_assoc]; conv_lhs => rw [hx']
import Mathlib.LinearAlgebra.Matrix.DotProduct import Mathlib.LinearAlgebra.Determinant import Mathlib.LinearAlgebra.Matrix.Diagonal #align_import data.matrix.rank from "leanprover-community/mathlib"@"17219820a8aa8abe85adf5dfde19af1dd1bd8ae7" open Matrix namespace Matrix open FiniteDimensional variable {l m n o R : Type*} [Fintype n] [Fintype o] section CommRing variable [CommRing R] noncomputable def rank (A : Matrix m n R) : ℕ := finrank R <| LinearMap.range A.mulVecLin #align matrix.rank Matrix.rank @[simp] theorem rank_one [StrongRankCondition R] [DecidableEq n] : rank (1 : Matrix n n R) = Fintype.card n := by rw [rank, mulVecLin_one, LinearMap.range_id, finrank_top, finrank_pi] #align matrix.rank_one Matrix.rank_one @[simp] theorem rank_zero [Nontrivial R] : rank (0 : Matrix m n R) = 0 := by rw [rank, mulVecLin_zero, LinearMap.range_zero, finrank_bot] #align matrix.rank_zero Matrix.rank_zero theorem rank_le_card_width [StrongRankCondition R] (A : Matrix m n R) : A.rank ≤ Fintype.card n := by haveI : Module.Finite R (n → R) := Module.Finite.pi haveI : Module.Free R (n → R) := Module.Free.pi _ _ exact A.mulVecLin.finrank_range_le.trans_eq (finrank_pi _) #align matrix.rank_le_card_width Matrix.rank_le_card_width theorem rank_le_width [StrongRankCondition R] {m n : ℕ} (A : Matrix (Fin m) (Fin n) R) : A.rank ≤ n := A.rank_le_card_width.trans <| (Fintype.card_fin n).le #align matrix.rank_le_width Matrix.rank_le_width theorem rank_mul_le_left [StrongRankCondition R] (A : Matrix m n R) (B : Matrix n o R) : (A * B).rank ≤ A.rank := by rw [rank, rank, mulVecLin_mul] exact Cardinal.toNat_le_toNat (LinearMap.rank_comp_le_left _ _) (rank_lt_aleph0 _ _) #align matrix.rank_mul_le_left Matrix.rank_mul_le_left theorem rank_mul_le_right [StrongRankCondition R] (A : Matrix m n R) (B : Matrix n o R) : (A * B).rank ≤ B.rank := by rw [rank, rank, mulVecLin_mul] exact finrank_le_finrank_of_rank_le_rank (LinearMap.lift_rank_comp_le_right _ _) (rank_lt_aleph0 _ _) #align matrix.rank_mul_le_right Matrix.rank_mul_le_right theorem rank_mul_le [StrongRankCondition R] (A : Matrix m n R) (B : Matrix n o R) : (A * B).rank ≤ min A.rank B.rank := le_min (rank_mul_le_left _ _) (rank_mul_le_right _ _) #align matrix.rank_mul_le Matrix.rank_mul_le theorem rank_unit [StrongRankCondition R] [DecidableEq n] (A : (Matrix n n R)ˣ) : (A : Matrix n n R).rank = Fintype.card n := by apply le_antisymm (rank_le_card_width (A : Matrix n n R)) _ have := rank_mul_le_left (A : Matrix n n R) (↑A⁻¹ : Matrix n n R) rwa [← Units.val_mul, mul_inv_self, Units.val_one, rank_one] at this #align matrix.rank_unit Matrix.rank_unit theorem rank_of_isUnit [StrongRankCondition R] [DecidableEq n] (A : Matrix n n R) (h : IsUnit A) : A.rank = Fintype.card n := by obtain ⟨A, rfl⟩ := h exact rank_unit A #align matrix.rank_of_is_unit Matrix.rank_of_isUnit @[simp] lemma rank_mul_eq_left_of_isUnit_det [DecidableEq n] (A : Matrix n n R) (B : Matrix m n R) (hA : IsUnit A.det) : (B * A).rank = B.rank := by suffices Function.Surjective A.mulVecLin by rw [rank, mulVecLin_mul, LinearMap.range_comp_of_range_eq_top _ (LinearMap.range_eq_top.mpr this), ← rank] intro v exact ⟨(A⁻¹).mulVecLin v, by simp [mul_nonsing_inv _ hA]⟩ @[simp] lemma rank_mul_eq_right_of_isUnit_det [Fintype m] [DecidableEq m] (A : Matrix m m R) (B : Matrix m n R) (hA : IsUnit A.det) : (A * B).rank = B.rank := by let b : Basis m R (m → R) := Pi.basisFun R m replace hA : IsUnit (LinearMap.toMatrix b b A.mulVecLin).det := by convert hA; rw [← LinearEquiv.eq_symm_apply]; rfl have hAB : mulVecLin (A * B) = (LinearEquiv.ofIsUnitDet hA).comp (mulVecLin B) := by ext; simp rw [rank, rank, hAB, LinearMap.range_comp, LinearEquiv.finrank_map_eq] theorem rank_submatrix_le [StrongRankCondition R] [Fintype m] (f : n → m) (e : n ≃ m) (A : Matrix m m R) : rank (A.submatrix f e) ≤ rank A := by rw [rank, rank, mulVecLin_submatrix, LinearMap.range_comp, LinearMap.range_comp, show LinearMap.funLeft R R e.symm = LinearEquiv.funCongrLeft R R e.symm from rfl, LinearEquiv.range, Submodule.map_top] exact Submodule.finrank_map_le _ _ #align matrix.rank_submatrix_le Matrix.rank_submatrix_le theorem rank_reindex [Fintype m] (e₁ e₂ : m ≃ n) (A : Matrix m m R) : rank (reindex e₁ e₂ A) = rank A := by rw [rank, rank, mulVecLin_reindex, LinearMap.range_comp, LinearMap.range_comp, LinearEquiv.range, Submodule.map_top, LinearEquiv.finrank_map_eq] #align matrix.rank_reindex Matrix.rank_reindex @[simp]
Mathlib/Data/Matrix/Rank.lean
140
142
theorem rank_submatrix [Fintype m] (A : Matrix m m R) (e₁ e₂ : n ≃ m) : rank (A.submatrix e₁ e₂) = rank A := by
simpa only [reindex_apply] using rank_reindex e₁.symm e₂.symm A
import Mathlib.Analysis.Calculus.ContDiff.Basic import Mathlib.Analysis.Calculus.Deriv.Linear import Mathlib.Analysis.Complex.Conformal import Mathlib.Analysis.Calculus.Conformal.NormedSpace #align_import analysis.complex.real_deriv from "leanprover-community/mathlib"@"3bce8d800a6f2b8f63fe1e588fd76a9ff4adcebe" section Conformality open Complex ContinuousLinearMap open scoped ComplexConjugate variable {E : Type*} [NormedAddCommGroup E] [NormedSpace ℂ E] {z : ℂ} {f : ℂ → E} theorem DifferentiableAt.conformalAt (h : DifferentiableAt ℂ f z) (hf' : deriv f z ≠ 0) : ConformalAt f z := by rw [conformalAt_iff_isConformalMap_fderiv, (h.hasFDerivAt.restrictScalars ℝ).fderiv] apply isConformalMap_complex_linear simpa only [Ne, ext_ring_iff] #align differentiable_at.conformal_at DifferentiableAt.conformalAt
Mathlib/Analysis/Complex/RealDeriv.lean
171
185
theorem conformalAt_iff_differentiableAt_or_differentiableAt_comp_conj {f : ℂ → ℂ} {z : ℂ} : ConformalAt f z ↔ (DifferentiableAt ℂ f z ∨ DifferentiableAt ℂ (f ∘ conj) (conj z)) ∧ fderiv ℝ f z ≠ 0 := by
rw [conformalAt_iff_isConformalMap_fderiv] rw [isConformalMap_iff_is_complex_or_conj_linear] apply and_congr_left intro h have h_diff := h.imp_symm fderiv_zero_of_not_differentiableAt apply or_congr · rw [differentiableAt_iff_restrictScalars ℝ h_diff] rw [← conj_conj z] at h_diff rw [differentiableAt_iff_restrictScalars ℝ (h_diff.comp _ conjCLE.differentiableAt)] refine exists_congr fun g => rfl.congr ?_ have : fderiv ℝ conj (conj z) = _ := conjCLE.fderiv simp [fderiv.comp _ h_diff conjCLE.differentiableAt, this, conj_conj]
import Mathlib.Topology.MetricSpace.HausdorffDistance import Mathlib.MeasureTheory.Constructions.BorelSpace.Order #align_import measure_theory.measure.regular from "leanprover-community/mathlib"@"bf6a01357ff5684b1ebcd0f1a13be314fc82c0bf" open Set Filter ENNReal Topology NNReal TopologicalSpace namespace MeasureTheory namespace Measure def InnerRegularWRT {α} {_ : MeasurableSpace α} (μ : Measure α) (p q : Set α → Prop) := ∀ ⦃U⦄, q U → ∀ r < μ U, ∃ K, K ⊆ U ∧ p K ∧ r < μ K #align measure_theory.measure.inner_regular MeasureTheory.Measure.InnerRegularWRT variable {α β : Type*} [MeasurableSpace α] [TopologicalSpace α] {μ : Measure α} class OuterRegular (μ : Measure α) : Prop where protected outerRegular : ∀ ⦃A : Set α⦄, MeasurableSet A → ∀ r > μ A, ∃ U, U ⊇ A ∧ IsOpen U ∧ μ U < r #align measure_theory.measure.outer_regular MeasureTheory.Measure.OuterRegular #align measure_theory.measure.outer_regular.outer_regular MeasureTheory.Measure.OuterRegular.outerRegular class Regular (μ : Measure α) extends IsFiniteMeasureOnCompacts μ, OuterRegular μ : Prop where innerRegular : InnerRegularWRT μ IsCompact IsOpen #align measure_theory.measure.regular MeasureTheory.Measure.Regular class WeaklyRegular (μ : Measure α) extends OuterRegular μ : Prop where protected innerRegular : InnerRegularWRT μ IsClosed IsOpen #align measure_theory.measure.weakly_regular MeasureTheory.Measure.WeaklyRegular #align measure_theory.measure.weakly_regular.inner_regular MeasureTheory.Measure.WeaklyRegular.innerRegular class InnerRegular (μ : Measure α) : Prop where protected innerRegular : InnerRegularWRT μ IsCompact (fun s ↦ MeasurableSet s) class InnerRegularCompactLTTop (μ : Measure α) : Prop where protected innerRegular : InnerRegularWRT μ IsCompact (fun s ↦ MeasurableSet s ∧ μ s ≠ ∞) -- see Note [lower instance priority] instance (priority := 100) Regular.weaklyRegular [R1Space α] [Regular μ] : WeaklyRegular μ where innerRegular := fun _U hU r hr ↦ let ⟨K, KU, K_comp, hK⟩ := Regular.innerRegular hU r hr ⟨closure K, K_comp.closure_subset_of_isOpen hU KU, isClosed_closure, hK.trans_le (measure_mono subset_closure)⟩ #align measure_theory.measure.regular.weakly_regular MeasureTheory.Measure.Regular.weaklyRegular namespace OuterRegular instance zero : OuterRegular (0 : Measure α) := ⟨fun A _ _r hr => ⟨univ, subset_univ A, isOpen_univ, hr⟩⟩ #align measure_theory.measure.outer_regular.zero MeasureTheory.Measure.OuterRegular.zero theorem _root_.Set.exists_isOpen_lt_of_lt [OuterRegular μ] (A : Set α) (r : ℝ≥0∞) (hr : μ A < r) : ∃ U, U ⊇ A ∧ IsOpen U ∧ μ U < r := by rcases OuterRegular.outerRegular (measurableSet_toMeasurable μ A) r (by rwa [measure_toMeasurable]) with ⟨U, hAU, hUo, hU⟩ exact ⟨U, (subset_toMeasurable _ _).trans hAU, hUo, hU⟩ #align set.exists_is_open_lt_of_lt Set.exists_isOpen_lt_of_lt theorem _root_.Set.measure_eq_iInf_isOpen (A : Set α) (μ : Measure α) [OuterRegular μ] : μ A = ⨅ (U : Set α) (_ : A ⊆ U) (_ : IsOpen U), μ U := by refine le_antisymm (le_iInf₂ fun s hs => le_iInf fun _ => μ.mono hs) ?_ refine le_of_forall_lt' fun r hr => ?_ simpa only [iInf_lt_iff, exists_prop] using A.exists_isOpen_lt_of_lt r hr #align set.measure_eq_infi_is_open Set.measure_eq_iInf_isOpen theorem _root_.Set.exists_isOpen_lt_add [OuterRegular μ] (A : Set α) (hA : μ A ≠ ∞) {ε : ℝ≥0∞} (hε : ε ≠ 0) : ∃ U, U ⊇ A ∧ IsOpen U ∧ μ U < μ A + ε := A.exists_isOpen_lt_of_lt _ (ENNReal.lt_add_right hA hε) #align set.exists_is_open_lt_add Set.exists_isOpen_lt_add
Mathlib/MeasureTheory/Measure/Regular.lean
361
366
theorem _root_.Set.exists_isOpen_le_add (A : Set α) (μ : Measure α) [OuterRegular μ] {ε : ℝ≥0∞} (hε : ε ≠ 0) : ∃ U, U ⊇ A ∧ IsOpen U ∧ μ U ≤ μ A + ε := by
rcases eq_or_ne (μ A) ∞ with (H | H) · exact ⟨univ, subset_univ _, isOpen_univ, by simp only [H, _root_.top_add, le_top]⟩ · rcases A.exists_isOpen_lt_add H hε with ⟨U, AU, U_open, hU⟩ exact ⟨U, AU, U_open, hU.le⟩
import Mathlib.Probability.IdentDistrib import Mathlib.MeasureTheory.Integral.DominatedConvergence import Mathlib.Analysis.SpecificLimits.FloorPow import Mathlib.Analysis.PSeries import Mathlib.Analysis.Asymptotics.SpecificAsymptotics #align_import probability.strong_law from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982" noncomputable section open MeasureTheory Filter Finset Asymptotics open Set (indicator) open scoped Topology MeasureTheory ProbabilityTheory ENNReal NNReal namespace ProbabilityTheory section Truncation variable {α : Type*} def truncation (f : α → ℝ) (A : ℝ) := indicator (Set.Ioc (-A) A) id ∘ f #align probability_theory.truncation ProbabilityTheory.truncation variable {m : MeasurableSpace α} {μ : Measure α} {f : α → ℝ} theorem _root_.MeasureTheory.AEStronglyMeasurable.truncation (hf : AEStronglyMeasurable f μ) {A : ℝ} : AEStronglyMeasurable (truncation f A) μ := by apply AEStronglyMeasurable.comp_aemeasurable _ hf.aemeasurable exact (stronglyMeasurable_id.indicator measurableSet_Ioc).aestronglyMeasurable #align measure_theory.ae_strongly_measurable.truncation MeasureTheory.AEStronglyMeasurable.truncation theorem abs_truncation_le_bound (f : α → ℝ) (A : ℝ) (x : α) : |truncation f A x| ≤ |A| := by simp only [truncation, Set.indicator, Set.mem_Icc, id, Function.comp_apply] split_ifs with h · exact abs_le_abs h.2 (neg_le.2 h.1.le) · simp [abs_nonneg] #align probability_theory.abs_truncation_le_bound ProbabilityTheory.abs_truncation_le_bound @[simp] theorem truncation_zero (f : α → ℝ) : truncation f 0 = 0 := by simp [truncation]; rfl #align probability_theory.truncation_zero ProbabilityTheory.truncation_zero theorem abs_truncation_le_abs_self (f : α → ℝ) (A : ℝ) (x : α) : |truncation f A x| ≤ |f x| := by simp only [truncation, indicator, Set.mem_Icc, id, Function.comp_apply] split_ifs · exact le_rfl · simp [abs_nonneg] #align probability_theory.abs_truncation_le_abs_self ProbabilityTheory.abs_truncation_le_abs_self
Mathlib/Probability/StrongLaw.lean
106
111
theorem truncation_eq_self {f : α → ℝ} {A : ℝ} {x : α} (h : |f x| < A) : truncation f A x = f x := by
simp only [truncation, indicator, Set.mem_Icc, id, Function.comp_apply, ite_eq_left_iff] intro H apply H.elim simp [(abs_lt.1 h).1, (abs_lt.1 h).2.le]
import Mathlib.Order.Filter.Bases #align_import order.filter.pi from "leanprover-community/mathlib"@"ce64cd319bb6b3e82f31c2d38e79080d377be451" open Set Function open scoped Classical open Filter namespace Filter variable {ι : Type*} {α : ι → Type*} {f f₁ f₂ : (i : ι) → Filter (α i)} {s : (i : ι) → Set (α i)} {p : ∀ i, α i → Prop} section CoprodCat -- for "Coprod" set_option linter.uppercaseLean3 false protected def coprodᵢ (f : ∀ i, Filter (α i)) : Filter (∀ i, α i) := ⨆ i : ι, comap (eval i) (f i) #align filter.Coprod Filter.coprodᵢ
Mathlib/Order/Filter/Pi.lean
229
230
theorem mem_coprodᵢ_iff {s : Set (∀ i, α i)} : s ∈ Filter.coprodᵢ f ↔ ∀ i : ι, ∃ t₁ ∈ f i, eval i ⁻¹' t₁ ⊆ s := by
simp [Filter.coprodᵢ]
import Batteries.Data.Fin.Basic namespace Fin attribute [norm_cast] val_last protected theorem le_antisymm_iff {x y : Fin n} : x = y ↔ x ≤ y ∧ y ≤ x := Fin.ext_iff.trans Nat.le_antisymm_iff protected theorem le_antisymm {x y : Fin n} (h1 : x ≤ y) (h2 : y ≤ x) : x = y := Fin.le_antisymm_iff.2 ⟨h1, h2⟩ @[simp] theorem coe_clamp (n m : Nat) : (clamp n m : Nat) = min n m := rfl @[simp] theorem size_enum (n) : (enum n).size = n := Array.size_ofFn .. @[simp] theorem enum_zero : (enum 0) = #[] := by simp [enum, Array.ofFn, Array.ofFn.go] @[simp] theorem getElem_enum (i) (h : i < (enum n).size) : (enum n)[i] = ⟨i, size_enum n ▸ h⟩ := Array.getElem_ofFn .. @[simp] theorem length_list (n) : (list n).length = n := by simp [list] @[simp] theorem get_list (i : Fin (list n).length) : (list n).get i = i.cast (length_list n) := by cases i; simp only [list]; rw [← Array.getElem_eq_data_get, getElem_enum, cast_mk] @[simp] theorem list_zero : list 0 = [] := by simp [list] theorem list_succ (n) : list (n+1) = 0 :: (list n).map Fin.succ := by apply List.ext_get; simp; intro i; cases i <;> simp theorem list_succ_last (n) : list (n+1) = (list n).map castSucc ++ [last n] := by rw [list_succ] induction n with | zero => rfl | succ n ih => rw [list_succ, List.map_cons castSucc, ih] simp [Function.comp_def, succ_castSucc] theorem list_reverse (n) : (list n).reverse = (list n).map rev := by induction n with | zero => rfl | succ n ih => conv => lhs; rw [list_succ_last] conv => rhs; rw [list_succ] simp [List.reverse_map, ih, Function.comp_def, rev_succ] theorem foldl_loop_lt (f : α → Fin n → α) (x) (h : m < n) : foldl.loop n f x m = foldl.loop n f (f x ⟨m, h⟩) (m+1) := by rw [foldl.loop, dif_pos h] theorem foldl_loop_eq (f : α → Fin n → α) (x) : foldl.loop n f x n = x := by rw [foldl.loop, dif_neg (Nat.lt_irrefl _)] theorem foldl_loop (f : α → Fin (n+1) → α) (x) (h : m < n+1) : foldl.loop (n+1) f x m = foldl.loop n (fun x i => f x i.succ) (f x ⟨m, h⟩) m := by if h' : m < n then rw [foldl_loop_lt _ _ h, foldl_loop_lt _ _ h', foldl_loop]; rfl else cases Nat.le_antisymm (Nat.le_of_lt_succ h) (Nat.not_lt.1 h') rw [foldl_loop_lt, foldl_loop_eq, foldl_loop_eq] termination_by n - m @[simp] theorem foldl_zero (f : α → Fin 0 → α) (x) : foldl 0 f x = x := by simp [foldl, foldl.loop] theorem foldl_succ (f : α → Fin (n+1) → α) (x) : foldl (n+1) f x = foldl n (fun x i => f x i.succ) (f x 0) := foldl_loop .. theorem foldl_succ_last (f : α → Fin (n+1) → α) (x) : foldl (n+1) f x = f (foldl n (f · ·.castSucc) x) (last n) := by rw [foldl_succ] induction n generalizing x with | zero => simp [foldl_succ, Fin.last] | succ n ih => rw [foldl_succ, ih (f · ·.succ), foldl_succ]; simp [succ_castSucc]
.lake/packages/batteries/Batteries/Data/Fin/Lemmas.lean
87
90
theorem foldl_eq_foldl_list (f : α → Fin n → α) (x) : foldl n f x = (list n).foldl f x := by
induction n generalizing x with | zero => rw [foldl_zero, list_zero, List.foldl_nil] | succ n ih => rw [foldl_succ, ih, list_succ, List.foldl_cons, List.foldl_map]
import Mathlib.LinearAlgebra.AffineSpace.AffineMap import Mathlib.Tactic.FieldSimp #align_import linear_algebra.affine_space.slope from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a" open AffineMap variable {k E PE : Type*} [Field k] [AddCommGroup E] [Module k E] [AddTorsor E PE] def slope (f : k → PE) (a b : k) : E := (b - a)⁻¹ • (f b -ᵥ f a) #align slope slope theorem slope_fun_def (f : k → PE) : slope f = fun a b => (b - a)⁻¹ • (f b -ᵥ f a) := rfl #align slope_fun_def slope_fun_def theorem slope_def_field (f : k → k) (a b : k) : slope f a b = (f b - f a) / (b - a) := (div_eq_inv_mul _ _).symm #align slope_def_field slope_def_field theorem slope_fun_def_field (f : k → k) (a : k) : slope f a = fun b => (f b - f a) / (b - a) := (div_eq_inv_mul _ _).symm #align slope_fun_def_field slope_fun_def_field @[simp] theorem slope_same (f : k → PE) (a : k) : (slope f a a : E) = 0 := by rw [slope, sub_self, inv_zero, zero_smul] #align slope_same slope_same theorem slope_def_module (f : k → E) (a b : k) : slope f a b = (b - a)⁻¹ • (f b - f a) := rfl #align slope_def_module slope_def_module @[simp] theorem sub_smul_slope (f : k → PE) (a b : k) : (b - a) • slope f a b = f b -ᵥ f a := by rcases eq_or_ne a b with (rfl | hne) · rw [sub_self, zero_smul, vsub_self] · rw [slope, smul_inv_smul₀ (sub_ne_zero.2 hne.symm)] #align sub_smul_slope sub_smul_slope theorem sub_smul_slope_vadd (f : k → PE) (a b : k) : (b - a) • slope f a b +ᵥ f a = f b := by rw [sub_smul_slope, vsub_vadd] #align sub_smul_slope_vadd sub_smul_slope_vadd @[simp] theorem slope_vadd_const (f : k → E) (c : PE) : (slope fun x => f x +ᵥ c) = slope f := by ext a b simp only [slope, vadd_vsub_vadd_cancel_right, vsub_eq_sub] #align slope_vadd_const slope_vadd_const @[simp] theorem slope_sub_smul (f : k → E) {a b : k} (h : a ≠ b) : slope (fun x => (x - a) • f x) a b = f b := by simp [slope, inv_smul_smul₀ (sub_ne_zero.2 h.symm)] #align slope_sub_smul slope_sub_smul theorem eq_of_slope_eq_zero {f : k → PE} {a b : k} (h : slope f a b = (0 : E)) : f a = f b := by rw [← sub_smul_slope_vadd f a b, h, smul_zero, zero_vadd] #align eq_of_slope_eq_zero eq_of_slope_eq_zero theorem AffineMap.slope_comp {F PF : Type*} [AddCommGroup F] [Module k F] [AddTorsor F PF] (f : PE →ᵃ[k] PF) (g : k → PE) (a b : k) : slope (f ∘ g) a b = f.linear (slope g a b) := by simp only [slope, (· ∘ ·), f.linear.map_smul, f.linearMap_vsub] #align affine_map.slope_comp AffineMap.slope_comp theorem LinearMap.slope_comp {F : Type*} [AddCommGroup F] [Module k F] (f : E →ₗ[k] F) (g : k → E) (a b : k) : slope (f ∘ g) a b = f (slope g a b) := f.toAffineMap.slope_comp g a b #align linear_map.slope_comp LinearMap.slope_comp theorem slope_comm (f : k → PE) (a b : k) : slope f a b = slope f b a := by rw [slope, slope, ← neg_vsub_eq_vsub_rev, smul_neg, ← neg_smul, neg_inv, neg_sub] #align slope_comm slope_comm @[simp] lemma slope_neg (f : k → E) (x y : k) : slope (fun t ↦ -f t) x y = -slope f x y := by simp only [slope_def_module, neg_sub_neg, ← smul_neg, neg_sub] theorem sub_div_sub_smul_slope_add_sub_div_sub_smul_slope (f : k → PE) (a b c : k) : ((b - a) / (c - a)) • slope f a b + ((c - b) / (c - a)) • slope f b c = slope f a c := by by_cases hab : a = b · subst hab rw [sub_self, zero_div, zero_smul, zero_add] by_cases hac : a = c · simp [hac] · rw [div_self (sub_ne_zero.2 <| Ne.symm hac), one_smul] by_cases hbc : b = c; · subst hbc simp [sub_ne_zero.2 (Ne.symm hab)] rw [add_comm] simp_rw [slope, div_eq_inv_mul, mul_smul, ← smul_add, smul_inv_smul₀ (sub_ne_zero.2 <| Ne.symm hab), smul_inv_smul₀ (sub_ne_zero.2 <| Ne.symm hbc), vsub_add_vsub_cancel] #align sub_div_sub_smul_slope_add_sub_div_sub_smul_slope sub_div_sub_smul_slope_add_sub_div_sub_smul_slope
Mathlib/LinearAlgebra/AffineSpace/Slope.lean
121
124
theorem lineMap_slope_slope_sub_div_sub (f : k → PE) (a b c : k) (h : a ≠ c) : lineMap (slope f a b) (slope f b c) ((c - b) / (c - a)) = slope f a c := by
field_simp [sub_ne_zero.2 h.symm, ← sub_div_sub_smul_slope_add_sub_div_sub_smul_slope f a b c, lineMap_apply_module]
import Mathlib.Algebra.BigOperators.Intervals import Mathlib.Algebra.BigOperators.Ring.List import Mathlib.Data.Int.ModEq import Mathlib.Data.Nat.Bits import Mathlib.Data.Nat.Log import Mathlib.Data.List.Indexes import Mathlib.Data.List.Palindrome import Mathlib.Tactic.IntervalCases import Mathlib.Tactic.Linarith import Mathlib.Tactic.Ring #align_import data.nat.digits from "leanprover-community/mathlib"@"369525b73f229ccd76a6ec0e0e0bf2be57599768" namespace Nat variable {n : ℕ} def digitsAux0 : ℕ → List ℕ | 0 => [] | n + 1 => [n + 1] #align nat.digits_aux_0 Nat.digitsAux0 def digitsAux1 (n : ℕ) : List ℕ := List.replicate n 1 #align nat.digits_aux_1 Nat.digitsAux1 def digitsAux (b : ℕ) (h : 2 ≤ b) : ℕ → List ℕ | 0 => [] | n + 1 => ((n + 1) % b) :: digitsAux b h ((n + 1) / b) decreasing_by exact Nat.div_lt_self (Nat.succ_pos _) h #align nat.digits_aux Nat.digitsAux @[simp] theorem digitsAux_zero (b : ℕ) (h : 2 ≤ b) : digitsAux b h 0 = [] := by rw [digitsAux] #align nat.digits_aux_zero Nat.digitsAux_zero theorem digitsAux_def (b : ℕ) (h : 2 ≤ b) (n : ℕ) (w : 0 < n) : digitsAux b h n = (n % b) :: digitsAux b h (n / b) := by cases n · cases w · rw [digitsAux] #align nat.digits_aux_def Nat.digitsAux_def def digits : ℕ → ℕ → List ℕ | 0 => digitsAux0 | 1 => digitsAux1 | b + 2 => digitsAux (b + 2) (by norm_num) #align nat.digits Nat.digits @[simp] theorem digits_zero (b : ℕ) : digits b 0 = [] := by rcases b with (_ | ⟨_ | ⟨_⟩⟩) <;> simp [digits, digitsAux0, digitsAux1] #align nat.digits_zero Nat.digits_zero -- @[simp] -- Porting note (#10618): simp can prove this theorem digits_zero_zero : digits 0 0 = [] := rfl #align nat.digits_zero_zero Nat.digits_zero_zero @[simp] theorem digits_zero_succ (n : ℕ) : digits 0 n.succ = [n + 1] := rfl #align nat.digits_zero_succ Nat.digits_zero_succ theorem digits_zero_succ' : ∀ {n : ℕ}, n ≠ 0 → digits 0 n = [n] | 0, h => (h rfl).elim | _ + 1, _ => rfl #align nat.digits_zero_succ' Nat.digits_zero_succ' @[simp] theorem digits_one (n : ℕ) : digits 1 n = List.replicate n 1 := rfl #align nat.digits_one Nat.digits_one -- @[simp] -- Porting note (#10685): dsimp can prove this theorem digits_one_succ (n : ℕ) : digits 1 (n + 1) = 1 :: digits 1 n := rfl #align nat.digits_one_succ Nat.digits_one_succ theorem digits_add_two_add_one (b n : ℕ) : digits (b + 2) (n + 1) = ((n + 1) % (b + 2)) :: digits (b + 2) ((n + 1) / (b + 2)) := by simp [digits, digitsAux_def] #align nat.digits_add_two_add_one Nat.digits_add_two_add_one @[simp] lemma digits_of_two_le_of_pos {b : ℕ} (hb : 2 ≤ b) (hn : 0 < n) : Nat.digits b n = n % b :: Nat.digits b (n / b) := by rw [Nat.eq_add_of_sub_eq hb rfl, Nat.eq_add_of_sub_eq hn rfl, Nat.digits_add_two_add_one] theorem digits_def' : ∀ {b : ℕ} (_ : 1 < b) {n : ℕ} (_ : 0 < n), digits b n = (n % b) :: digits b (n / b) | 0, h => absurd h (by decide) | 1, h => absurd h (by decide) | b + 2, _ => digitsAux_def _ (by simp) _ #align nat.digits_def' Nat.digits_def' @[simp] theorem digits_of_lt (b x : ℕ) (hx : x ≠ 0) (hxb : x < b) : digits b x = [x] := by rcases exists_eq_succ_of_ne_zero hx with ⟨x, rfl⟩ rcases Nat.exists_eq_add_of_le' ((Nat.le_add_left 1 x).trans_lt hxb) with ⟨b, rfl⟩ rw [digits_add_two_add_one, div_eq_of_lt hxb, digits_zero, mod_eq_of_lt hxb] #align nat.digits_of_lt Nat.digits_of_lt theorem digits_add (b : ℕ) (h : 1 < b) (x y : ℕ) (hxb : x < b) (hxy : x ≠ 0 ∨ y ≠ 0) : digits b (x + b * y) = x :: digits b y := by rcases Nat.exists_eq_add_of_le' h with ⟨b, rfl : _ = _ + 2⟩ cases y · simp [hxb, hxy.resolve_right (absurd rfl)] dsimp [digits] rw [digitsAux_def] · congr · simp [Nat.add_mod, mod_eq_of_lt hxb] · simp [add_mul_div_left, div_eq_of_lt hxb] · apply Nat.succ_pos #align nat.digits_add Nat.digits_add -- If we had a function converting a list into a polynomial, -- and appropriate lemmas about that function, -- we could rewrite this in terms of that. def ofDigits {α : Type*} [Semiring α] (b : α) : List ℕ → α | [] => 0 | h :: t => h + b * ofDigits b t #align nat.of_digits Nat.ofDigits
Mathlib/Data/Nat/Digits.lean
167
172
theorem ofDigits_eq_foldr {α : Type*} [Semiring α] (b : α) (L : List ℕ) : ofDigits b L = List.foldr (fun x y => ↑x + b * y) 0 L := by
induction' L with d L ih · rfl · dsimp [ofDigits] rw [ih]
import Mathlib.Data.Set.Lattice #align_import data.set.intervals.disjoint from "leanprover-community/mathlib"@"207cfac9fcd06138865b5d04f7091e46d9320432" universe u v w variable {ι : Sort u} {α : Type v} {β : Type w} open Set open OrderDual (toDual) namespace Set section Preorder variable [Preorder α] {a b c : α} @[simp] theorem Iic_disjoint_Ioi (h : a ≤ b) : Disjoint (Iic a) (Ioi b) := disjoint_left.mpr fun _ ha hb => (h.trans_lt hb).not_le ha #align set.Iic_disjoint_Ioi Set.Iic_disjoint_Ioi @[simp] theorem Iio_disjoint_Ici (h : a ≤ b) : Disjoint (Iio a) (Ici b) := disjoint_left.mpr fun _ ha hb => (h.trans_lt' ha).not_le hb @[simp] theorem Iic_disjoint_Ioc (h : a ≤ b) : Disjoint (Iic a) (Ioc b c) := (Iic_disjoint_Ioi h).mono le_rfl Ioc_subset_Ioi_self #align set.Iic_disjoint_Ioc Set.Iic_disjoint_Ioc @[simp] theorem Ioc_disjoint_Ioc_same : Disjoint (Ioc a b) (Ioc b c) := (Iic_disjoint_Ioc le_rfl).mono Ioc_subset_Iic_self le_rfl #align set.Ioc_disjoint_Ioc_same Set.Ioc_disjoint_Ioc_same @[simp] theorem Ico_disjoint_Ico_same : Disjoint (Ico a b) (Ico b c) := disjoint_left.mpr fun _ hab hbc => hab.2.not_le hbc.1 #align set.Ico_disjoint_Ico_same Set.Ico_disjoint_Ico_same @[simp] theorem Ici_disjoint_Iic : Disjoint (Ici a) (Iic b) ↔ ¬a ≤ b := by rw [Set.disjoint_iff_inter_eq_empty, Ici_inter_Iic, Icc_eq_empty_iff] #align set.Ici_disjoint_Iic Set.Ici_disjoint_Iic @[simp] theorem Iic_disjoint_Ici : Disjoint (Iic a) (Ici b) ↔ ¬b ≤ a := disjoint_comm.trans Ici_disjoint_Iic #align set.Iic_disjoint_Ici Set.Iic_disjoint_Ici @[simp] theorem Ioc_disjoint_Ioi (h : b ≤ c) : Disjoint (Ioc a b) (Ioi c) := disjoint_left.mpr (fun _ hx hy ↦ (hx.2.trans h).not_lt hy) theorem Ioc_disjoint_Ioi_same : Disjoint (Ioc a b) (Ioi b) := Ioc_disjoint_Ioi le_rfl @[simp] theorem iUnion_Iic : ⋃ a : α, Iic a = univ := iUnion_eq_univ_iff.2 fun x => ⟨x, right_mem_Iic⟩ #align set.Union_Iic Set.iUnion_Iic @[simp] theorem iUnion_Ici : ⋃ a : α, Ici a = univ := iUnion_eq_univ_iff.2 fun x => ⟨x, left_mem_Ici⟩ #align set.Union_Ici Set.iUnion_Ici @[simp] theorem iUnion_Icc_right (a : α) : ⋃ b, Icc a b = Ici a := by simp only [← Ici_inter_Iic, ← inter_iUnion, iUnion_Iic, inter_univ] #align set.Union_Icc_right Set.iUnion_Icc_right @[simp] theorem iUnion_Ioc_right (a : α) : ⋃ b, Ioc a b = Ioi a := by simp only [← Ioi_inter_Iic, ← inter_iUnion, iUnion_Iic, inter_univ] #align set.Union_Ioc_right Set.iUnion_Ioc_right @[simp] theorem iUnion_Icc_left (b : α) : ⋃ a, Icc a b = Iic b := by simp only [← Ici_inter_Iic, ← iUnion_inter, iUnion_Ici, univ_inter] #align set.Union_Icc_left Set.iUnion_Icc_left @[simp] theorem iUnion_Ico_left (b : α) : ⋃ a, Ico a b = Iio b := by simp only [← Ici_inter_Iio, ← iUnion_inter, iUnion_Ici, univ_inter] #align set.Union_Ico_left Set.iUnion_Ico_left @[simp] theorem iUnion_Iio [NoMaxOrder α] : ⋃ a : α, Iio a = univ := iUnion_eq_univ_iff.2 exists_gt #align set.Union_Iio Set.iUnion_Iio @[simp] theorem iUnion_Ioi [NoMinOrder α] : ⋃ a : α, Ioi a = univ := iUnion_eq_univ_iff.2 exists_lt #align set.Union_Ioi Set.iUnion_Ioi @[simp] theorem iUnion_Ico_right [NoMaxOrder α] (a : α) : ⋃ b, Ico a b = Ici a := by simp only [← Ici_inter_Iio, ← inter_iUnion, iUnion_Iio, inter_univ] #align set.Union_Ico_right Set.iUnion_Ico_right @[simp]
Mathlib/Order/Interval/Set/Disjoint.lean
122
123
theorem iUnion_Ioo_right [NoMaxOrder α] (a : α) : ⋃ b, Ioo a b = Ioi a := by
simp only [← Ioi_inter_Iio, ← inter_iUnion, iUnion_Iio, inter_univ]
import Mathlib.Probability.Notation import Mathlib.Probability.Integration import Mathlib.MeasureTheory.Function.L2Space #align_import probability.variance from "leanprover-community/mathlib"@"f0c8bf9245297a541f468be517f1bde6195105e9" open MeasureTheory Filter Finset noncomputable section open scoped MeasureTheory ProbabilityTheory ENNReal NNReal namespace ProbabilityTheory -- Porting note: this lemma replaces `ENNReal.toReal_bit0`, which does not exist in Lean 4 private lemma coe_two : ENNReal.toReal 2 = (2 : ℝ) := rfl -- Porting note: Consider if `evariance` or `eVariance` is better. Also, -- consider `eVariationOn` in `Mathlib.Analysis.BoundedVariation`. def evariance {Ω : Type*} {_ : MeasurableSpace Ω} (X : Ω → ℝ) (μ : Measure Ω) : ℝ≥0∞ := ∫⁻ ω, (‖X ω - μ[X]‖₊ : ℝ≥0∞) ^ 2 ∂μ #align probability_theory.evariance ProbabilityTheory.evariance def variance {Ω : Type*} {_ : MeasurableSpace Ω} (X : Ω → ℝ) (μ : Measure Ω) : ℝ := (evariance X μ).toReal #align probability_theory.variance ProbabilityTheory.variance variable {Ω : Type*} {m : MeasurableSpace Ω} {X : Ω → ℝ} {μ : Measure Ω} theorem _root_.MeasureTheory.Memℒp.evariance_lt_top [IsFiniteMeasure μ] (hX : Memℒp X 2 μ) : evariance X μ < ∞ := by have := ENNReal.pow_lt_top (hX.sub <| memℒp_const <| μ[X]).2 2 rw [snorm_eq_lintegral_rpow_nnnorm two_ne_zero ENNReal.two_ne_top, ← ENNReal.rpow_two] at this simp only [coe_two, Pi.sub_apply, ENNReal.one_toReal, one_div] at this rw [← ENNReal.rpow_mul, inv_mul_cancel (two_ne_zero : (2 : ℝ) ≠ 0), ENNReal.rpow_one] at this simp_rw [ENNReal.rpow_two] at this exact this #align measure_theory.mem_ℒp.evariance_lt_top MeasureTheory.Memℒp.evariance_lt_top theorem evariance_eq_top [IsFiniteMeasure μ] (hXm : AEStronglyMeasurable X μ) (hX : ¬Memℒp X 2 μ) : evariance X μ = ∞ := by by_contra h rw [← Ne, ← lt_top_iff_ne_top] at h have : Memℒp (fun ω => X ω - μ[X]) 2 μ := by refine ⟨hXm.sub aestronglyMeasurable_const, ?_⟩ rw [snorm_eq_lintegral_rpow_nnnorm two_ne_zero ENNReal.two_ne_top] simp only [coe_two, ENNReal.one_toReal, ENNReal.rpow_two, Ne] exact ENNReal.rpow_lt_top_of_nonneg (by linarith) h.ne refine hX ?_ -- Porting note: `μ[X]` without whitespace is ambiguous as it could be GetElem, -- and `convert` cannot disambiguate based on typeclass inference failure. convert this.add (memℒp_const <| μ [X]) ext ω rw [Pi.add_apply, sub_add_cancel] #align probability_theory.evariance_eq_top ProbabilityTheory.evariance_eq_top theorem evariance_lt_top_iff_memℒp [IsFiniteMeasure μ] (hX : AEStronglyMeasurable X μ) : evariance X μ < ∞ ↔ Memℒp X 2 μ := by refine ⟨?_, MeasureTheory.Memℒp.evariance_lt_top⟩ contrapose rw [not_lt, top_le_iff] exact evariance_eq_top hX #align probability_theory.evariance_lt_top_iff_mem_ℒp ProbabilityTheory.evariance_lt_top_iff_memℒp
Mathlib/Probability/Variance.lean
100
103
theorem _root_.MeasureTheory.Memℒp.ofReal_variance_eq [IsFiniteMeasure μ] (hX : Memℒp X 2 μ) : ENNReal.ofReal (variance X μ) = evariance X μ := by
rw [variance, ENNReal.ofReal_toReal] exact hX.evariance_lt_top.ne
import Mathlib.Data.Complex.Basic import Mathlib.Data.Real.Sqrt #align_import data.complex.basic from "leanprover-community/mathlib"@"31c24aa72e7b3e5ed97a8412470e904f82b81004" open Set ComplexConjugate namespace Complex namespace AbsTheory -- We develop enough theory to bundle `abs` into an `AbsoluteValue` before making things public; -- this is so there's not two versions of it hanging around. local notation "abs" z => Real.sqrt (normSq z) private theorem mul_self_abs (z : ℂ) : ((abs z) * abs z) = normSq z := Real.mul_self_sqrt (normSq_nonneg _) private theorem abs_nonneg' (z : ℂ) : 0 ≤ abs z := Real.sqrt_nonneg _
Mathlib/Data/Complex/Abs.lean
34
34
theorem abs_conj (z : ℂ) : (abs conj z) = abs z := by
simp
import Mathlib.Algebra.Ring.Prod import Mathlib.GroupTheory.OrderOfElement import Mathlib.Tactic.FinCases #align_import data.zmod.basic from "leanprover-community/mathlib"@"74ad1c88c77e799d2fea62801d1dbbd698cff1b7" assert_not_exists Submodule open Function namespace ZMod instance charZero : CharZero (ZMod 0) := inferInstanceAs (CharZero ℤ) def val : ∀ {n : ℕ}, ZMod n → ℕ | 0 => Int.natAbs | n + 1 => ((↑) : Fin (n + 1) → ℕ) #align zmod.val ZMod.val theorem val_lt {n : ℕ} [NeZero n] (a : ZMod n) : a.val < n := by cases n · cases NeZero.ne 0 rfl exact Fin.is_lt a #align zmod.val_lt ZMod.val_lt theorem val_le {n : ℕ} [NeZero n] (a : ZMod n) : a.val ≤ n := a.val_lt.le #align zmod.val_le ZMod.val_le @[simp] theorem val_zero : ∀ {n}, (0 : ZMod n).val = 0 | 0 => rfl | _ + 1 => rfl #align zmod.val_zero ZMod.val_zero @[simp] theorem val_one' : (1 : ZMod 0).val = 1 := rfl #align zmod.val_one' ZMod.val_one' @[simp] theorem val_neg' {n : ZMod 0} : (-n).val = n.val := Int.natAbs_neg n #align zmod.val_neg' ZMod.val_neg' @[simp] theorem val_mul' {m n : ZMod 0} : (m * n).val = m.val * n.val := Int.natAbs_mul m n #align zmod.val_mul' ZMod.val_mul' @[simp]
Mathlib/Data/ZMod/Basic.lean
84
88
theorem val_natCast {n : ℕ} (a : ℕ) : (a : ZMod n).val = a % n := by
cases n · rw [Nat.mod_zero] exact Int.natAbs_ofNat a · apply Fin.val_natCast
import Mathlib.Analysis.Convex.Between import Mathlib.Analysis.Convex.Jensen import Mathlib.Analysis.Convex.Topology import Mathlib.Analysis.Normed.Group.Pointwise import Mathlib.Analysis.NormedSpace.AddTorsor #align_import analysis.convex.normed from "leanprover-community/mathlib"@"a63928c34ec358b5edcda2bf7513c50052a5230f" variable {ι : Type*} {E P : Type*} open Metric Set open scoped Convex variable [SeminormedAddCommGroup E] [NormedSpace ℝ E] [PseudoMetricSpace P] [NormedAddTorsor E P] variable {s t : Set E} theorem convexOn_norm (hs : Convex ℝ s) : ConvexOn ℝ s norm := ⟨hs, fun x _ y _ a b ha hb _ => calc ‖a • x + b • y‖ ≤ ‖a • x‖ + ‖b • y‖ := norm_add_le _ _ _ = a * ‖x‖ + b * ‖y‖ := by rw [norm_smul, norm_smul, Real.norm_of_nonneg ha, Real.norm_of_nonneg hb]⟩ #align convex_on_norm convexOn_norm theorem convexOn_univ_norm : ConvexOn ℝ univ (norm : E → ℝ) := convexOn_norm convex_univ #align convex_on_univ_norm convexOn_univ_norm theorem convexOn_dist (z : E) (hs : Convex ℝ s) : ConvexOn ℝ s fun z' => dist z' z := by simpa [dist_eq_norm, preimage_preimage] using (convexOn_norm (hs.translate (-z))).comp_affineMap (AffineMap.id ℝ E - AffineMap.const ℝ E z) #align convex_on_dist convexOn_dist theorem convexOn_univ_dist (z : E) : ConvexOn ℝ univ fun z' => dist z' z := convexOn_dist z convex_univ #align convex_on_univ_dist convexOn_univ_dist theorem convex_ball (a : E) (r : ℝ) : Convex ℝ (Metric.ball a r) := by simpa only [Metric.ball, sep_univ] using (convexOn_univ_dist a).convex_lt r #align convex_ball convex_ball
Mathlib/Analysis/Convex/Normed.lean
66
67
theorem convex_closedBall (a : E) (r : ℝ) : Convex ℝ (Metric.closedBall a r) := by
simpa only [Metric.closedBall, sep_univ] using (convexOn_univ_dist a).convex_le r
import Mathlib.Algebra.Group.Basic import Mathlib.Algebra.Group.Hom.Defs #align_import algebra.hom.group from "leanprover-community/mathlib"@"a148d797a1094ab554ad4183a4ad6f130358ef64" -- `NeZero` cannot be additivised, hence its theory should be developed outside of the -- `Algebra.Group` folder. assert_not_exists NeZero variable {α β M N P : Type*} -- monoids variable {G : Type*} {H : Type*} -- groups variable {F : Type*} namespace MulHom @[to_additive "Given two additive morphisms `f`, `g` to an additive commutative semigroup, `f + g` is the additive morphism sending `x` to `f x + g x`."] instance [Mul M] [CommSemigroup N] : Mul (M →ₙ* N) := ⟨fun f g => { toFun := fun m => f m * g m, map_mul' := fun x y => by show f (x * y) * g (x * y) = f x * g x * (f y * g y) rw [f.map_mul, g.map_mul, ← mul_assoc, ← mul_assoc, mul_right_comm (f x)] }⟩ @[to_additive (attr := simp)] theorem mul_apply {M N} [Mul M] [CommSemigroup N] (f g : M →ₙ* N) (x : M) : (f * g) x = f x * g x := rfl #align mul_hom.mul_apply MulHom.mul_apply #align add_hom.add_apply AddHom.add_apply @[to_additive] theorem mul_comp [Mul M] [Mul N] [CommSemigroup P] (g₁ g₂ : N →ₙ* P) (f : M →ₙ* N) : (g₁ * g₂).comp f = g₁.comp f * g₂.comp f := rfl #align mul_hom.mul_comp MulHom.mul_comp #align add_hom.add_comp AddHom.add_comp @[to_additive]
Mathlib/Algebra/Group/Hom/Basic.lean
110
113
theorem comp_mul [Mul M] [CommSemigroup N] [CommSemigroup P] (g : N →ₙ* P) (f₁ f₂ : M →ₙ* N) : g.comp (f₁ * f₂) = g.comp f₁ * g.comp f₂ := by
ext simp only [mul_apply, Function.comp_apply, map_mul, coe_comp]
import Mathlib.Algebra.Algebra.Defs import Mathlib.Algebra.Order.Group.Basic import Mathlib.Algebra.Order.Ring.Basic import Mathlib.RingTheory.Localization.Basic import Mathlib.SetTheory.Game.Birthday import Mathlib.SetTheory.Surreal.Basic #align_import set_theory.surreal.dyadic from "leanprover-community/mathlib"@"92ca63f0fb391a9ca5f22d2409a6080e786d99f7" universe u namespace SetTheory namespace PGame def powHalf : ℕ → PGame | 0 => 1 | n + 1 => ⟨PUnit, PUnit, 0, fun _ => powHalf n⟩ #align pgame.pow_half SetTheory.PGame.powHalf @[simp] theorem powHalf_zero : powHalf 0 = 1 := rfl #align pgame.pow_half_zero SetTheory.PGame.powHalf_zero theorem powHalf_leftMoves (n) : (powHalf n).LeftMoves = PUnit := by cases n <;> rfl #align pgame.pow_half_left_moves SetTheory.PGame.powHalf_leftMoves theorem powHalf_zero_rightMoves : (powHalf 0).RightMoves = PEmpty := rfl #align pgame.pow_half_zero_right_moves SetTheory.PGame.powHalf_zero_rightMoves theorem powHalf_succ_rightMoves (n) : (powHalf (n + 1)).RightMoves = PUnit := rfl #align pgame.pow_half_succ_right_moves SetTheory.PGame.powHalf_succ_rightMoves @[simp] theorem powHalf_moveLeft (n i) : (powHalf n).moveLeft i = 0 := by cases n <;> cases i <;> rfl #align pgame.pow_half_move_left SetTheory.PGame.powHalf_moveLeft @[simp] theorem powHalf_succ_moveRight (n i) : (powHalf (n + 1)).moveRight i = powHalf n := rfl #align pgame.pow_half_succ_move_right SetTheory.PGame.powHalf_succ_moveRight instance uniquePowHalfLeftMoves (n) : Unique (powHalf n).LeftMoves := by cases n <;> exact PUnit.unique #align pgame.unique_pow_half_left_moves SetTheory.PGame.uniquePowHalfLeftMoves instance isEmpty_powHalf_zero_rightMoves : IsEmpty (powHalf 0).RightMoves := inferInstanceAs (IsEmpty PEmpty) #align pgame.is_empty_pow_half_zero_right_moves SetTheory.PGame.isEmpty_powHalf_zero_rightMoves instance uniquePowHalfSuccRightMoves (n) : Unique (powHalf (n + 1)).RightMoves := PUnit.unique #align pgame.unique_pow_half_succ_right_moves SetTheory.PGame.uniquePowHalfSuccRightMoves @[simp] theorem birthday_half : birthday (powHalf 1) = 2 := by rw [birthday_def]; simp #align pgame.birthday_half SetTheory.PGame.birthday_half theorem numeric_powHalf (n) : (powHalf n).Numeric := by induction' n with n hn · exact numeric_one · constructor · simpa using hn.moveLeft_lt default · exact ⟨fun _ => numeric_zero, fun _ => hn⟩ #align pgame.numeric_pow_half SetTheory.PGame.numeric_powHalf theorem powHalf_succ_lt_powHalf (n : ℕ) : powHalf (n + 1) < powHalf n := (numeric_powHalf (n + 1)).lt_moveRight default #align pgame.pow_half_succ_lt_pow_half SetTheory.PGame.powHalf_succ_lt_powHalf theorem powHalf_succ_le_powHalf (n : ℕ) : powHalf (n + 1) ≤ powHalf n := (powHalf_succ_lt_powHalf n).le #align pgame.pow_half_succ_le_pow_half SetTheory.PGame.powHalf_succ_le_powHalf theorem powHalf_le_one (n : ℕ) : powHalf n ≤ 1 := by induction' n with n hn · exact le_rfl · exact (powHalf_succ_le_powHalf n).trans hn #align pgame.pow_half_le_one SetTheory.PGame.powHalf_le_one theorem powHalf_succ_lt_one (n : ℕ) : powHalf (n + 1) < 1 := (powHalf_succ_lt_powHalf n).trans_le <| powHalf_le_one n #align pgame.pow_half_succ_lt_one SetTheory.PGame.powHalf_succ_lt_one theorem powHalf_pos (n : ℕ) : 0 < powHalf n := by rw [← lf_iff_lt numeric_zero (numeric_powHalf n), zero_lf_le]; simp #align pgame.pow_half_pos SetTheory.PGame.powHalf_pos theorem zero_le_powHalf (n : ℕ) : 0 ≤ powHalf n := (powHalf_pos n).le #align pgame.zero_le_pow_half SetTheory.PGame.zero_le_powHalf
Mathlib/SetTheory/Surreal/Dyadic.lean
124
156
theorem add_powHalf_succ_self_eq_powHalf (n) : powHalf (n + 1) + powHalf (n + 1) ≈ powHalf n := by
induction' n using Nat.strong_induction_on with n hn constructor <;> rw [le_iff_forall_lf] <;> constructor · rintro (⟨⟨⟩⟩ | ⟨⟨⟩⟩) <;> apply lf_of_lt · calc 0 + powHalf n.succ ≈ powHalf n.succ := zero_add_equiv _ _ < powHalf n := powHalf_succ_lt_powHalf n · calc powHalf n.succ + 0 ≈ powHalf n.succ := add_zero_equiv _ _ < powHalf n := powHalf_succ_lt_powHalf n · cases' n with n · rintro ⟨⟩ rintro ⟨⟩ apply lf_of_moveRight_le swap · exact Sum.inl default calc powHalf n.succ + powHalf (n.succ + 1) ≤ powHalf n.succ + powHalf n.succ := add_le_add_left (powHalf_succ_le_powHalf _) _ _ ≈ powHalf n := hn _ (Nat.lt_succ_self n) · simp only [powHalf_moveLeft, forall_const] apply lf_of_lt calc 0 ≈ 0 + 0 := Equiv.symm (add_zero_equiv 0) _ ≤ powHalf n.succ + 0 := add_le_add_right (zero_le_powHalf _) _ _ < powHalf n.succ + powHalf n.succ := add_lt_add_left (powHalf_pos _) _ · rintro (⟨⟨⟩⟩ | ⟨⟨⟩⟩) <;> apply lf_of_lt · calc powHalf n ≈ powHalf n + 0 := Equiv.symm (add_zero_equiv _) _ < powHalf n + powHalf n.succ := add_lt_add_left (powHalf_pos _) _ · calc powHalf n ≈ 0 + powHalf n := Equiv.symm (zero_add_equiv _) _ < powHalf n.succ + powHalf n := add_lt_add_right (powHalf_pos _) _
import Mathlib.Topology.Order.Basic open Set Filter OrderDual open scoped Topology section OrderClosedTopology variable {α : Type*} [LinearOrder α] [TopologicalSpace α] [OrderClosedTopology α] {a b c d : α} @[simp] theorem nhdsSet_Ioi : 𝓝ˢ (Ioi a) = 𝓟 (Ioi a) := isOpen_Ioi.nhdsSet_eq @[simp] theorem nhdsSet_Iio : 𝓝ˢ (Iio a) = 𝓟 (Iio a) := isOpen_Iio.nhdsSet_eq @[simp] theorem nhdsSet_Ioo : 𝓝ˢ (Ioo a b) = 𝓟 (Ioo a b) := isOpen_Ioo.nhdsSet_eq theorem nhdsSet_Ici : 𝓝ˢ (Ici a) = 𝓝 a ⊔ 𝓟 (Ioi a) := by rw [← Ioi_insert, nhdsSet_insert, nhdsSet_Ioi] theorem nhdsSet_Iic : 𝓝ˢ (Iic a) = 𝓝 a ⊔ 𝓟 (Iio a) := nhdsSet_Ici (α := αᵒᵈ)
Mathlib/Topology/Order/NhdsSet.lean
41
42
theorem nhdsSet_Ico (h : a < b) : 𝓝ˢ (Ico a b) = 𝓝 a ⊔ 𝓟 (Ioo a b) := by
rw [← Ioo_insert_left h, nhdsSet_insert, nhdsSet_Ioo]
import Mathlib.Data.Num.Lemmas import Mathlib.Data.Nat.Prime import Mathlib.Tactic.Ring #align_import data.num.prime from "leanprover-community/mathlib"@"58581d0fe523063f5651df0619be2bf65012a94a" namespace PosNum def minFacAux (n : PosNum) : ℕ → PosNum → PosNum | 0, _ => n | fuel + 1, k => if n < k.bit1 * k.bit1 then n else if k.bit1 ∣ n then k.bit1 else minFacAux n fuel k.succ #align pos_num.min_fac_aux PosNum.minFacAux set_option linter.deprecated false in theorem minFacAux_to_nat {fuel : ℕ} {n k : PosNum} (h : Nat.sqrt n < fuel + k.bit1) : (minFacAux n fuel k : ℕ) = Nat.minFacAux n k.bit1 := by induction' fuel with fuel ih generalizing k <;> rw [minFacAux, Nat.minFacAux] · rw [Nat.zero_add, Nat.sqrt_lt] at h simp only [h, ite_true] simp_rw [← mul_to_nat] simp only [cast_lt, dvd_to_nat] split_ifs <;> try rfl rw [ih] <;> [congr; convert Nat.lt_succ_of_lt h using 1] <;> simp only [_root_.bit1, _root_.bit0, cast_bit1, cast_succ, Nat.succ_eq_add_one, add_assoc, add_left_comm, ← one_add_one_eq_two] #align pos_num.min_fac_aux_to_nat PosNum.minFacAux_to_nat def minFac : PosNum → PosNum | 1 => 1 | bit0 _ => 2 | bit1 n => minFacAux (bit1 n) n 1 #align pos_num.min_fac PosNum.minFac @[simp]
Mathlib/Data/Num/Prime.lean
65
83
theorem minFac_to_nat (n : PosNum) : (minFac n : ℕ) = Nat.minFac n := by
cases' n with n · rfl · rw [minFac, Nat.minFac_eq, if_neg] swap · simp rw [minFacAux_to_nat] · rfl simp only [cast_one, cast_bit1] unfold _root_.bit1 _root_.bit0 rw [Nat.sqrt_lt] calc (n : ℕ) + (n : ℕ) + 1 ≤ (n : ℕ) + (n : ℕ) + (n : ℕ) := by simp _ = (n : ℕ) * (1 + 1 + 1) := by simp only [mul_add, mul_one] _ < _ := by set_option simprocs false in simp [mul_lt_mul] · rw [minFac, Nat.minFac_eq, if_pos] · rfl simp
import Mathlib.Analysis.Calculus.Deriv.Mul import Mathlib.Analysis.Calculus.Deriv.Comp #align_import analysis.calculus.deriv.inv from "leanprover-community/mathlib"@"3bce8d800a6f2b8f63fe1e588fd76a9ff4adcebe" universe u v w open scoped Classical open Topology Filter ENNReal open Filter Asymptotics Set open ContinuousLinearMap (smulRight smulRight_one_eq_iff) variable {𝕜 : Type u} [NontriviallyNormedField 𝕜] variable {F : Type v} [NormedAddCommGroup F] [NormedSpace 𝕜 F] variable {E : Type w} [NormedAddCommGroup E] [NormedSpace 𝕜 E] variable {f f₀ f₁ g : 𝕜 → F} variable {f' f₀' f₁' g' : F} variable {x : 𝕜} variable {s t : Set 𝕜} variable {L : Filter 𝕜} section Inverse theorem hasStrictDerivAt_inv (hx : x ≠ 0) : HasStrictDerivAt Inv.inv (-(x ^ 2)⁻¹) x := by suffices (fun p : 𝕜 × 𝕜 => (p.1 - p.2) * ((x * x)⁻¹ - (p.1 * p.2)⁻¹)) =o[𝓝 (x, x)] fun p => (p.1 - p.2) * 1 by refine this.congr' ?_ (eventually_of_forall fun _ => mul_one _) refine Eventually.mono ((isOpen_ne.prod isOpen_ne).mem_nhds ⟨hx, hx⟩) ?_ rintro ⟨y, z⟩ ⟨hy, hz⟩ simp only [mem_setOf_eq] at hy hz -- hy : y ≠ 0, hz : z ≠ 0 field_simp [hx, hy, hz] ring refine (isBigO_refl (fun p : 𝕜 × 𝕜 => p.1 - p.2) _).mul_isLittleO ((isLittleO_one_iff 𝕜).2 ?_) rw [← sub_self (x * x)⁻¹] exact tendsto_const_nhds.sub ((continuous_mul.tendsto (x, x)).inv₀ <| mul_ne_zero hx hx) #align has_strict_deriv_at_inv hasStrictDerivAt_inv theorem hasDerivAt_inv (x_ne_zero : x ≠ 0) : HasDerivAt (fun y => y⁻¹) (-(x ^ 2)⁻¹) x := (hasStrictDerivAt_inv x_ne_zero).hasDerivAt #align has_deriv_at_inv hasDerivAt_inv theorem hasDerivWithinAt_inv (x_ne_zero : x ≠ 0) (s : Set 𝕜) : HasDerivWithinAt (fun x => x⁻¹) (-(x ^ 2)⁻¹) s x := (hasDerivAt_inv x_ne_zero).hasDerivWithinAt #align has_deriv_within_at_inv hasDerivWithinAt_inv theorem differentiableAt_inv : DifferentiableAt 𝕜 (fun x => x⁻¹) x ↔ x ≠ 0 := ⟨fun H => NormedField.continuousAt_inv.1 H.continuousAt, fun H => (hasDerivAt_inv H).differentiableAt⟩ #align differentiable_at_inv differentiableAt_inv theorem differentiableWithinAt_inv (x_ne_zero : x ≠ 0) : DifferentiableWithinAt 𝕜 (fun x => x⁻¹) s x := (differentiableAt_inv.2 x_ne_zero).differentiableWithinAt #align differentiable_within_at_inv differentiableWithinAt_inv theorem differentiableOn_inv : DifferentiableOn 𝕜 (fun x : 𝕜 => x⁻¹) { x | x ≠ 0 } := fun _x hx => differentiableWithinAt_inv hx #align differentiable_on_inv differentiableOn_inv theorem deriv_inv : deriv (fun x => x⁻¹) x = -(x ^ 2)⁻¹ := by rcases eq_or_ne x 0 with (rfl | hne) · simp [deriv_zero_of_not_differentiableAt (mt differentiableAt_inv.1 (not_not.2 rfl))] · exact (hasDerivAt_inv hne).deriv #align deriv_inv deriv_inv @[simp] theorem deriv_inv' : (deriv fun x : 𝕜 => x⁻¹) = fun x => -(x ^ 2)⁻¹ := funext fun _ => deriv_inv #align deriv_inv' deriv_inv' theorem derivWithin_inv (x_ne_zero : x ≠ 0) (hxs : UniqueDiffWithinAt 𝕜 s x) : derivWithin (fun x => x⁻¹) s x = -(x ^ 2)⁻¹ := by rw [DifferentiableAt.derivWithin (differentiableAt_inv.2 x_ne_zero) hxs] exact deriv_inv #align deriv_within_inv derivWithin_inv theorem hasFDerivAt_inv (x_ne_zero : x ≠ 0) : HasFDerivAt (fun x => x⁻¹) (smulRight (1 : 𝕜 →L[𝕜] 𝕜) (-(x ^ 2)⁻¹) : 𝕜 →L[𝕜] 𝕜) x := hasDerivAt_inv x_ne_zero #align has_fderiv_at_inv hasFDerivAt_inv theorem hasFDerivWithinAt_inv (x_ne_zero : x ≠ 0) : HasFDerivWithinAt (fun x => x⁻¹) (smulRight (1 : 𝕜 →L[𝕜] 𝕜) (-(x ^ 2)⁻¹) : 𝕜 →L[𝕜] 𝕜) s x := (hasFDerivAt_inv x_ne_zero).hasFDerivWithinAt #align has_fderiv_within_at_inv hasFDerivWithinAt_inv theorem fderiv_inv : fderiv 𝕜 (fun x => x⁻¹) x = smulRight (1 : 𝕜 →L[𝕜] 𝕜) (-(x ^ 2)⁻¹) := by rw [← deriv_fderiv, deriv_inv] #align fderiv_inv fderiv_inv
Mathlib/Analysis/Calculus/Deriv/Inv.lean
118
121
theorem fderivWithin_inv (x_ne_zero : x ≠ 0) (hxs : UniqueDiffWithinAt 𝕜 s x) : fderivWithin 𝕜 (fun x => x⁻¹) s x = smulRight (1 : 𝕜 →L[𝕜] 𝕜) (-(x ^ 2)⁻¹) := by
rw [DifferentiableAt.fderivWithin (differentiableAt_inv.2 x_ne_zero) hxs] exact fderiv_inv
import Mathlib.Analysis.Calculus.Deriv.Basic import Mathlib.MeasureTheory.Constructions.BorelSpace.ContinuousLinearMap import Mathlib.MeasureTheory.Covering.BesicovitchVectorSpace import Mathlib.MeasureTheory.Measure.Lebesgue.EqHaar import Mathlib.Analysis.NormedSpace.Pointwise import Mathlib.MeasureTheory.Constructions.Polish import Mathlib.Analysis.Calculus.InverseFunctionTheorem.ApproximatesLinearOn #align_import measure_theory.function.jacobian from "leanprover-community/mathlib"@"b84aee748341da06a6d78491367e2c0e9f15e8a5" open MeasureTheory MeasureTheory.Measure Metric Filter Set FiniteDimensional Asymptotics TopologicalSpace open scoped NNReal ENNReal Topology Pointwise variable {E F : Type*} [NormedAddCommGroup E] [NormedSpace ℝ E] [FiniteDimensional ℝ E] [NormedAddCommGroup F] [NormedSpace ℝ F] {s : Set E} {f : E → E} {f' : E → E →L[ℝ] E}
Mathlib/MeasureTheory/Function/Jacobian.lean
109
243
theorem exists_closed_cover_approximatesLinearOn_of_hasFDerivWithinAt [SecondCountableTopology F] (f : E → F) (s : Set E) (f' : E → E →L[ℝ] F) (hf' : ∀ x ∈ s, HasFDerivWithinAt f (f' x) s x) (r : (E →L[ℝ] F) → ℝ≥0) (rpos : ∀ A, r A ≠ 0) : ∃ (t : ℕ → Set E) (A : ℕ → E →L[ℝ] F), (∀ n, IsClosed (t n)) ∧ (s ⊆ ⋃ n, t n) ∧ (∀ n, ApproximatesLinearOn f (A n) (s ∩ t n) (r (A n))) ∧ (s.Nonempty → ∀ n, ∃ y ∈ s, A n = f' y) := by
/- Choose countably many linear maps `f' z`. For every such map, if `f` has a derivative at `x` close enough to `f' z`, then `f y - f x` is well approximated by `f' z (y - x)` for `y` close enough to `x`, say on a ball of radius `r` (or even `u n` for some `n`, where `u` is a fixed sequence tending to `0`). Let `M n z` be the points where this happens. Then this set is relatively closed inside `s`, and moreover in every closed ball of radius `u n / 3` inside it the map is well approximated by `f' z`. Using countably many closed balls to split `M n z` into small diameter subsets `K n z p`, one obtains the desired sets `t q` after reindexing. -/ -- exclude the trivial case where `s` is empty rcases eq_empty_or_nonempty s with (rfl | hs) · refine ⟨fun _ => ∅, fun _ => 0, ?_, ?_, ?_, ?_⟩ <;> simp -- we will use countably many linear maps. Select these from all the derivatives since the -- space of linear maps is second-countable obtain ⟨T, T_count, hT⟩ : ∃ T : Set s, T.Countable ∧ ⋃ x ∈ T, ball (f' (x : E)) (r (f' x)) = ⋃ x : s, ball (f' x) (r (f' x)) := TopologicalSpace.isOpen_iUnion_countable _ fun x => isOpen_ball -- fix a sequence `u` of positive reals tending to zero. obtain ⟨u, _, u_pos, u_lim⟩ : ∃ u : ℕ → ℝ, StrictAnti u ∧ (∀ n : ℕ, 0 < u n) ∧ Tendsto u atTop (𝓝 0) := exists_seq_strictAnti_tendsto (0 : ℝ) -- `M n z` is the set of points `x` such that `f y - f x` is close to `f' z (y - x)` for `y` -- in the ball of radius `u n` around `x`. let M : ℕ → T → Set E := fun n z => {x | x ∈ s ∧ ∀ y ∈ s ∩ ball x (u n), ‖f y - f x - f' z (y - x)‖ ≤ r (f' z) * ‖y - x‖} -- As `f` is differentiable everywhere on `s`, the sets `M n z` cover `s` by design. have s_subset : ∀ x ∈ s, ∃ (n : ℕ) (z : T), x ∈ M n z := by intro x xs obtain ⟨z, zT, hz⟩ : ∃ z ∈ T, f' x ∈ ball (f' (z : E)) (r (f' z)) := by have : f' x ∈ ⋃ z ∈ T, ball (f' (z : E)) (r (f' z)) := by rw [hT] refine mem_iUnion.2 ⟨⟨x, xs⟩, ?_⟩ simpa only [mem_ball, Subtype.coe_mk, dist_self] using (rpos (f' x)).bot_lt rwa [mem_iUnion₂, bex_def] at this obtain ⟨ε, εpos, hε⟩ : ∃ ε : ℝ, 0 < ε ∧ ‖f' x - f' z‖ + ε ≤ r (f' z) := by refine ⟨r (f' z) - ‖f' x - f' z‖, ?_, le_of_eq (by abel)⟩ simpa only [sub_pos] using mem_ball_iff_norm.mp hz obtain ⟨δ, δpos, hδ⟩ : ∃ (δ : ℝ), 0 < δ ∧ ball x δ ∩ s ⊆ {y | ‖f y - f x - (f' x) (y - x)‖ ≤ ε * ‖y - x‖} := Metric.mem_nhdsWithin_iff.1 ((hf' x xs).isLittleO.def εpos) obtain ⟨n, hn⟩ : ∃ n, u n < δ := ((tendsto_order.1 u_lim).2 _ δpos).exists refine ⟨n, ⟨z, zT⟩, ⟨xs, ?_⟩⟩ intro y hy calc ‖f y - f x - (f' z) (y - x)‖ = ‖f y - f x - (f' x) (y - x) + (f' x - f' z) (y - x)‖ := by congr 1 simp only [ContinuousLinearMap.coe_sub', map_sub, Pi.sub_apply] abel _ ≤ ‖f y - f x - (f' x) (y - x)‖ + ‖(f' x - f' z) (y - x)‖ := norm_add_le _ _ _ ≤ ε * ‖y - x‖ + ‖f' x - f' z‖ * ‖y - x‖ := by refine add_le_add (hδ ?_) (ContinuousLinearMap.le_opNorm _ _) rw [inter_comm] exact inter_subset_inter_right _ (ball_subset_ball hn.le) hy _ ≤ r (f' z) * ‖y - x‖ := by rw [← add_mul, add_comm] gcongr -- the sets `M n z` are relatively closed in `s`, as all the conditions defining it are clearly -- closed have closure_M_subset : ∀ n z, s ∩ closure (M n z) ⊆ M n z := by rintro n z x ⟨xs, hx⟩ refine ⟨xs, fun y hy => ?_⟩ obtain ⟨a, aM, a_lim⟩ : ∃ a : ℕ → E, (∀ k, a k ∈ M n z) ∧ Tendsto a atTop (𝓝 x) := mem_closure_iff_seq_limit.1 hx have L1 : Tendsto (fun k : ℕ => ‖f y - f (a k) - (f' z) (y - a k)‖) atTop (𝓝 ‖f y - f x - (f' z) (y - x)‖) := by apply Tendsto.norm have L : Tendsto (fun k => f (a k)) atTop (𝓝 (f x)) := by apply (hf' x xs).continuousWithinAt.tendsto.comp apply tendsto_nhdsWithin_of_tendsto_nhds_of_eventually_within _ a_lim exact eventually_of_forall fun k => (aM k).1 apply Tendsto.sub (tendsto_const_nhds.sub L) exact ((f' z).continuous.tendsto _).comp (tendsto_const_nhds.sub a_lim) have L2 : Tendsto (fun k : ℕ => (r (f' z) : ℝ) * ‖y - a k‖) atTop (𝓝 (r (f' z) * ‖y - x‖)) := (tendsto_const_nhds.sub a_lim).norm.const_mul _ have I : ∀ᶠ k in atTop, ‖f y - f (a k) - (f' z) (y - a k)‖ ≤ r (f' z) * ‖y - a k‖ := by have L : Tendsto (fun k => dist y (a k)) atTop (𝓝 (dist y x)) := tendsto_const_nhds.dist a_lim filter_upwards [(tendsto_order.1 L).2 _ hy.2] intro k hk exact (aM k).2 y ⟨hy.1, hk⟩ exact le_of_tendsto_of_tendsto L1 L2 I -- choose a dense sequence `d p` rcases TopologicalSpace.exists_dense_seq E with ⟨d, hd⟩ -- split `M n z` into subsets `K n z p` of small diameters by intersecting with the ball -- `closedBall (d p) (u n / 3)`. let K : ℕ → T → ℕ → Set E := fun n z p => closure (M n z) ∩ closedBall (d p) (u n / 3) -- on the sets `K n z p`, the map `f` is well approximated by `f' z` by design. have K_approx : ∀ (n) (z : T) (p), ApproximatesLinearOn f (f' z) (s ∩ K n z p) (r (f' z)) := by intro n z p x hx y hy have yM : y ∈ M n z := closure_M_subset _ _ ⟨hy.1, hy.2.1⟩ refine yM.2 _ ⟨hx.1, ?_⟩ calc dist x y ≤ dist x (d p) + dist y (d p) := dist_triangle_right _ _ _ _ ≤ u n / 3 + u n / 3 := add_le_add hx.2.2 hy.2.2 _ < u n := by linarith [u_pos n] -- the sets `K n z p` are also closed, again by design. have K_closed : ∀ (n) (z : T) (p), IsClosed (K n z p) := fun n z p => isClosed_closure.inter isClosed_ball -- reindex the sets `K n z p`, to let them only depend on an integer parameter `q`. obtain ⟨F, hF⟩ : ∃ F : ℕ → ℕ × T × ℕ, Function.Surjective F := by haveI : Encodable T := T_count.toEncodable have : Nonempty T := by rcases hs with ⟨x, xs⟩ rcases s_subset x xs with ⟨n, z, _⟩ exact ⟨z⟩ inhabit ↥T exact ⟨_, Encodable.surjective_decode_iget (ℕ × T × ℕ)⟩ -- these sets `t q = K n z p` will do refine ⟨fun q => K (F q).1 (F q).2.1 (F q).2.2, fun q => f' (F q).2.1, fun n => K_closed _ _ _, fun x xs => ?_, fun q => K_approx _ _ _, fun _ q => ⟨(F q).2.1, (F q).2.1.1.2, rfl⟩⟩ -- the only fact that needs further checking is that they cover `s`. -- we already know that any point `x ∈ s` belongs to a set `M n z`. obtain ⟨n, z, hnz⟩ : ∃ (n : ℕ) (z : T), x ∈ M n z := s_subset x xs -- by density, it also belongs to a ball `closedBall (d p) (u n / 3)`. obtain ⟨p, hp⟩ : ∃ p : ℕ, x ∈ closedBall (d p) (u n / 3) := by have : Set.Nonempty (ball x (u n / 3)) := by simp only [nonempty_ball]; linarith [u_pos n] obtain ⟨p, hp⟩ : ∃ p : ℕ, d p ∈ ball x (u n / 3) := hd.exists_mem_open isOpen_ball this exact ⟨p, (mem_ball'.1 hp).le⟩ -- choose `q` for which `t q = K n z p`. obtain ⟨q, hq⟩ : ∃ q, F q = (n, z, p) := hF _ -- then `x` belongs to `t q`. apply mem_iUnion.2 ⟨q, _⟩ simp (config := { zeta := false }) only [K, hq, mem_inter_iff, hp, and_true] exact subset_closure hnz
import Mathlib.Data.Fin.Tuple.Basic import Mathlib.Data.List.Join #align_import data.list.of_fn from "leanprover-community/mathlib"@"bf27744463e9620ca4e4ebe951fe83530ae6949b" universe u variable {α : Type u} open Nat namespace List #noalign list.length_of_fn_aux @[simp] theorem length_ofFn_go {n} (f : Fin n → α) (i j h) : length (ofFn.go f i j h) = i := by induction i generalizing j <;> simp_all [ofFn.go] @[simp] theorem length_ofFn {n} (f : Fin n → α) : length (ofFn f) = n := by simp [ofFn, length_ofFn_go] #align list.length_of_fn List.length_ofFn #noalign list.nth_of_fn_aux
Mathlib/Data/List/OfFn.lean
50
54
theorem get_ofFn_go {n} (f : Fin n → α) (i j h) (k) (hk) : get (ofFn.go f i j h) ⟨k, hk⟩ = f ⟨j + k, by simp at hk; omega⟩ := by
let i+1 := i cases k <;> simp [ofFn.go, get_ofFn_go (i := i)] congr 2; omega
import Mathlib.Probability.Kernel.Disintegration.Unique import Mathlib.Probability.Notation #align_import probability.kernel.cond_distrib from "leanprover-community/mathlib"@"00abe0695d8767201e6d008afa22393978bb324d" open MeasureTheory Set Filter TopologicalSpace open scoped ENNReal MeasureTheory ProbabilityTheory namespace ProbabilityTheory variable {α β Ω F : Type*} [MeasurableSpace Ω] [StandardBorelSpace Ω] [Nonempty Ω] [NormedAddCommGroup F] {mα : MeasurableSpace α} {μ : Measure α} [IsFiniteMeasure μ] {X : α → β} {Y : α → Ω} noncomputable irreducible_def condDistrib {_ : MeasurableSpace α} [MeasurableSpace β] (Y : α → Ω) (X : α → β) (μ : Measure α) [IsFiniteMeasure μ] : kernel β Ω := (μ.map fun a => (X a, Y a)).condKernel #align probability_theory.cond_distrib ProbabilityTheory.condDistrib instance [MeasurableSpace β] : IsMarkovKernel (condDistrib Y X μ) := by rw [condDistrib]; infer_instance variable {mβ : MeasurableSpace β} {s : Set Ω} {t : Set β} {f : β × Ω → F} lemma condDistrib_apply_of_ne_zero [MeasurableSingletonClass β] (hY : Measurable Y) (x : β) (hX : μ.map X {x} ≠ 0) (s : Set Ω) : condDistrib Y X μ x s = (μ.map X {x})⁻¹ * μ.map (fun a => (X a, Y a)) ({x} ×ˢ s) := by rw [condDistrib, Measure.condKernel_apply_of_ne_zero _ s] · rw [Measure.fst_map_prod_mk hY] · rwa [Measure.fst_map_prod_mk hY] section Measurability theorem measurable_condDistrib (hs : MeasurableSet s) : Measurable[mβ.comap X] fun a => condDistrib Y X μ (X a) s := (kernel.measurable_coe _ hs).comp (Measurable.of_comap_le le_rfl) #align probability_theory.measurable_cond_distrib ProbabilityTheory.measurable_condDistrib
Mathlib/Probability/Kernel/CondDistrib.lean
88
93
theorem _root_.MeasureTheory.AEStronglyMeasurable.ae_integrable_condDistrib_map_iff (hY : AEMeasurable Y μ) (hf : AEStronglyMeasurable f (μ.map fun a => (X a, Y a))) : (∀ᵐ a ∂μ.map X, Integrable (fun ω => f (a, ω)) (condDistrib Y X μ a)) ∧ Integrable (fun a => ∫ ω, ‖f (a, ω)‖ ∂condDistrib Y X μ a) (μ.map X) ↔ Integrable f (μ.map fun a => (X a, Y a)) := by
rw [condDistrib, ← hf.ae_integrable_condKernel_iff, Measure.fst_map_prod_mk₀ hY]
import Mathlib.Analysis.Complex.Basic import Mathlib.Analysis.SpecificLimits.Normed open Filter Finset open scoped Topology namespace Complex section StolzSet open Real def stolzSet (M : ℝ) : Set ℂ := {z | ‖z‖ < 1 ∧ ‖1 - z‖ < M * (1 - ‖z‖)} def stolzCone (s : ℝ) : Set ℂ := {z | |z.im| < s * (1 - z.re)}
Mathlib/Analysis/Complex/AbelLimit.lean
47
54
theorem stolzSet_empty {M : ℝ} (hM : M ≤ 1) : stolzSet M = ∅ := by
ext z rw [stolzSet, Set.mem_setOf, Set.mem_empty_iff_false, iff_false, not_and, not_lt, ← sub_pos] intro zn calc _ ≤ 1 * (1 - ‖z‖) := mul_le_mul_of_nonneg_right hM zn.le _ = ‖(1 : ℂ)‖ - ‖z‖ := by rw [one_mul, norm_one] _ ≤ _ := norm_sub_norm_le _ _
import Mathlib.FieldTheory.IsAlgClosed.AlgebraicClosure import Mathlib.RingTheory.IntegralDomain #align_import field_theory.primitive_element from "leanprover-community/mathlib"@"df76f43357840485b9d04ed5dee5ab115d420e87" noncomputable section open scoped Classical Polynomial open FiniteDimensional Polynomial IntermediateField namespace Field section PrimitiveElementFinite variable (F : Type*) [Field F] (E : Type*) [Field E] [Algebra F E]
Mathlib/FieldTheory/PrimitiveElement.lean
56
67
theorem exists_primitive_element_of_finite_top [Finite E] : ∃ α : E, F⟮α⟯ = ⊤ := by
obtain ⟨α, hα⟩ := @IsCyclic.exists_generator Eˣ _ _ use α rw [eq_top_iff] rintro x - by_cases hx : x = 0 · rw [hx] exact F⟮α.val⟯.zero_mem · obtain ⟨n, hn⟩ := Set.mem_range.mp (hα (Units.mk0 x hx)) simp only at hn rw [show x = α ^ n by norm_cast; rw [hn, Units.val_mk0]] exact zpow_mem (mem_adjoin_simple_self F (E := E) ↑α) n
import Mathlib.Algebra.Order.Floor import Mathlib.Topology.Algebra.Order.Group import Mathlib.Topology.Order.Basic #align_import topology.algebra.order.floor from "leanprover-community/mathlib"@"84dc0bd6619acaea625086d6f53cb35cdd554219" open Filter Function Int Set Topology variable {α β γ : Type*} [LinearOrderedRing α] [FloorRing α] theorem tendsto_floor_atTop : Tendsto (floor : α → ℤ) atTop atTop := floor_mono.tendsto_atTop_atTop fun b => ⟨(b + 1 : ℤ), by rw [floor_intCast]; exact (lt_add_one _).le⟩ #align tendsto_floor_at_top tendsto_floor_atTop theorem tendsto_floor_atBot : Tendsto (floor : α → ℤ) atBot atBot := floor_mono.tendsto_atBot_atBot fun b => ⟨b, (floor_intCast _).le⟩ #align tendsto_floor_at_bot tendsto_floor_atBot theorem tendsto_ceil_atTop : Tendsto (ceil : α → ℤ) atTop atTop := ceil_mono.tendsto_atTop_atTop fun b => ⟨b, (ceil_intCast _).ge⟩ #align tendsto_ceil_at_top tendsto_ceil_atTop theorem tendsto_ceil_atBot : Tendsto (ceil : α → ℤ) atBot atBot := ceil_mono.tendsto_atBot_atBot fun b => ⟨(b - 1 : ℤ), by rw [ceil_intCast]; exact (sub_one_lt _).le⟩ #align tendsto_ceil_at_bot tendsto_ceil_atBot variable [TopologicalSpace α] theorem continuousOn_floor (n : ℤ) : ContinuousOn (fun x => floor x : α → α) (Ico n (n + 1) : Set α) := (continuousOn_congr <| floor_eq_on_Ico' n).mpr continuousOn_const #align continuous_on_floor continuousOn_floor theorem continuousOn_ceil (n : ℤ) : ContinuousOn (fun x => ceil x : α → α) (Ioc (n - 1) n : Set α) := (continuousOn_congr <| ceil_eq_on_Ioc' n).mpr continuousOn_const #align continuous_on_ceil continuousOn_ceil section OrderClosedTopology variable [OrderClosedTopology α] -- Porting note (#10756): new theorem theorem tendsto_floor_right_pure_floor (x : α) : Tendsto (floor : α → ℤ) (𝓝[≥] x) (pure ⌊x⌋) := tendsto_pure.2 <| mem_of_superset (Ico_mem_nhdsWithin_Ici' <| lt_floor_add_one x) fun _y hy => floor_eq_on_Ico _ _ ⟨(floor_le x).trans hy.1, hy.2⟩ -- Porting note (#10756): new theorem theorem tendsto_floor_right_pure (n : ℤ) : Tendsto (floor : α → ℤ) (𝓝[≥] n) (pure n) := by simpa only [floor_intCast] using tendsto_floor_right_pure_floor (n : α) -- Porting note (#10756): new theorem theorem tendsto_ceil_left_pure_ceil (x : α) : Tendsto (ceil : α → ℤ) (𝓝[≤] x) (pure ⌈x⌉) := tendsto_pure.2 <| mem_of_superset (Ioc_mem_nhdsWithin_Iic' <| sub_lt_iff_lt_add.2 <| ceil_lt_add_one _) fun _y hy => ceil_eq_on_Ioc _ _ ⟨hy.1, hy.2.trans (le_ceil _)⟩ -- Porting note (#10756): new theorem theorem tendsto_ceil_left_pure (n : ℤ) : Tendsto (ceil : α → ℤ) (𝓝[≤] n) (pure n) := by simpa only [ceil_intCast] using tendsto_ceil_left_pure_ceil (n : α) -- Porting note (#10756): new theorem theorem tendsto_floor_left_pure_ceil_sub_one (x : α) : Tendsto (floor : α → ℤ) (𝓝[<] x) (pure (⌈x⌉ - 1)) := have h₁ : ↑(⌈x⌉ - 1) < x := by rw [cast_sub, cast_one, sub_lt_iff_lt_add]; exact ceil_lt_add_one _ have h₂ : x ≤ ↑(⌈x⌉ - 1) + 1 := by rw [cast_sub, cast_one, sub_add_cancel]; exact le_ceil _ tendsto_pure.2 <| mem_of_superset (Ico_mem_nhdsWithin_Iio' h₁) fun _y hy => floor_eq_on_Ico _ _ ⟨hy.1, hy.2.trans_le h₂⟩ -- Porting note (#10756): new theorem theorem tendsto_floor_left_pure_sub_one (n : ℤ) : Tendsto (floor : α → ℤ) (𝓝[<] n) (pure (n - 1)) := by simpa only [ceil_intCast] using tendsto_floor_left_pure_ceil_sub_one (n : α) -- Porting note (#10756): new theorem theorem tendsto_ceil_right_pure_floor_add_one (x : α) : Tendsto (ceil : α → ℤ) (𝓝[>] x) (pure (⌊x⌋ + 1)) := have : ↑(⌊x⌋ + 1) - 1 ≤ x := by rw [cast_add, cast_one, add_sub_cancel_right]; exact floor_le _ tendsto_pure.2 <| mem_of_superset (Ioc_mem_nhdsWithin_Ioi' <| lt_succ_floor _) fun _y hy => ceil_eq_on_Ioc _ _ ⟨this.trans_lt hy.1, hy.2⟩ -- Porting note (#10756): new theorem
Mathlib/Topology/Algebra/Order/Floor.lean
108
110
theorem tendsto_ceil_right_pure_add_one (n : ℤ) : Tendsto (ceil : α → ℤ) (𝓝[>] n) (pure (n + 1)) := by
simpa only [floor_intCast] using tendsto_ceil_right_pure_floor_add_one (n : α)
import Mathlib.Order.Filter.Bases #align_import order.filter.pi from "leanprover-community/mathlib"@"ce64cd319bb6b3e82f31c2d38e79080d377be451" open Set Function open scoped Classical open Filter namespace Filter variable {ι : Type*} {α : ι → Type*} {f f₁ f₂ : (i : ι) → Filter (α i)} {s : (i : ι) → Set (α i)} {p : ∀ i, α i → Prop} section Pi def pi (f : ∀ i, Filter (α i)) : Filter (∀ i, α i) := ⨅ i, comap (eval i) (f i) #align filter.pi Filter.pi instance pi.isCountablyGenerated [Countable ι] [∀ i, IsCountablyGenerated (f i)] : IsCountablyGenerated (pi f) := iInf.isCountablyGenerated _ #align filter.pi.is_countably_generated Filter.pi.isCountablyGenerated theorem tendsto_eval_pi (f : ∀ i, Filter (α i)) (i : ι) : Tendsto (eval i) (pi f) (f i) := tendsto_iInf' i tendsto_comap #align filter.tendsto_eval_pi Filter.tendsto_eval_pi theorem tendsto_pi {β : Type*} {m : β → ∀ i, α i} {l : Filter β} : Tendsto m l (pi f) ↔ ∀ i, Tendsto (fun x => m x i) l (f i) := by simp only [pi, tendsto_iInf, tendsto_comap_iff]; rfl #align filter.tendsto_pi Filter.tendsto_pi alias ⟨Tendsto.apply, _⟩ := tendsto_pi theorem le_pi {g : Filter (∀ i, α i)} : g ≤ pi f ↔ ∀ i, Tendsto (eval i) g (f i) := tendsto_pi #align filter.le_pi Filter.le_pi @[mono] theorem pi_mono (h : ∀ i, f₁ i ≤ f₂ i) : pi f₁ ≤ pi f₂ := iInf_mono fun i => comap_mono <| h i #align filter.pi_mono Filter.pi_mono theorem mem_pi_of_mem (i : ι) {s : Set (α i)} (hs : s ∈ f i) : eval i ⁻¹' s ∈ pi f := mem_iInf_of_mem i <| preimage_mem_comap hs #align filter.mem_pi_of_mem Filter.mem_pi_of_mem theorem pi_mem_pi {I : Set ι} (hI : I.Finite) (h : ∀ i ∈ I, s i ∈ f i) : I.pi s ∈ pi f := by rw [pi_def, biInter_eq_iInter] refine mem_iInf_of_iInter hI (fun i => ?_) Subset.rfl exact preimage_mem_comap (h i i.2) #align filter.pi_mem_pi Filter.pi_mem_pi
Mathlib/Order/Filter/Pi.lean
80
88
theorem mem_pi {s : Set (∀ i, α i)} : s ∈ pi f ↔ ∃ I : Set ι, I.Finite ∧ ∃ t : ∀ i, Set (α i), (∀ i, t i ∈ f i) ∧ I.pi t ⊆ s := by
constructor · simp only [pi, mem_iInf', mem_comap, pi_def] rintro ⟨I, If, V, hVf, -, rfl, -⟩ choose t htf htV using hVf exact ⟨I, If, t, htf, iInter₂_mono fun i _ => htV i⟩ · rintro ⟨I, If, t, htf, hts⟩ exact mem_of_superset (pi_mem_pi If fun i _ => htf i) hts
import Mathlib.Algebra.Order.Field.Basic import Mathlib.Algebra.Order.Ring.Rat import Mathlib.Data.Multiset.Sort import Mathlib.Data.PNat.Basic import Mathlib.Data.PNat.Interval import Mathlib.Tactic.NormNum import Mathlib.Tactic.IntervalCases #align_import number_theory.ADE_inequality from "leanprover-community/mathlib"@"0a0ec35061ed9960bf0e7ffb0335f44447b58977" namespace ADEInequality open Multiset -- Porting note: ADE is a special name, exceptionally in upper case in Lean3 set_option linter.uppercaseLean3 false def A' (q r : ℕ+) : Multiset ℕ+ := {1, q, r} #align ADE_inequality.A' ADEInequality.A' def A (r : ℕ+) : Multiset ℕ+ := A' 1 r #align ADE_inequality.A ADEInequality.A def D' (r : ℕ+) : Multiset ℕ+ := {2, 2, r} #align ADE_inequality.D' ADEInequality.D' def E' (r : ℕ+) : Multiset ℕ+ := {2, 3, r} #align ADE_inequality.E' ADEInequality.E' def E6 : Multiset ℕ+ := E' 3 #align ADE_inequality.E6 ADEInequality.E6 def E7 : Multiset ℕ+ := E' 4 #align ADE_inequality.E7 ADEInequality.E7 def E8 : Multiset ℕ+ := E' 5 #align ADE_inequality.E8 ADEInequality.E8 def sumInv (pqr : Multiset ℕ+) : ℚ := Multiset.sum (pqr.map fun (x : ℕ+) => x⁻¹) #align ADE_inequality.sum_inv ADEInequality.sumInv theorem sumInv_pqr (p q r : ℕ+) : sumInv {p, q, r} = (p : ℚ)⁻¹ + (q : ℚ)⁻¹ + (r : ℚ)⁻¹ := by simp only [sumInv, add_zero, insert_eq_cons, add_assoc, map_cons, sum_cons, map_singleton, sum_singleton] #align ADE_inequality.sum_inv_pqr ADEInequality.sumInv_pqr def Admissible (pqr : Multiset ℕ+) : Prop := (∃ q r, A' q r = pqr) ∨ (∃ r, D' r = pqr) ∨ E' 3 = pqr ∨ E' 4 = pqr ∨ E' 5 = pqr #align ADE_inequality.admissible ADEInequality.Admissible theorem admissible_A' (q r : ℕ+) : Admissible (A' q r) := Or.inl ⟨q, r, rfl⟩ #align ADE_inequality.admissible_A' ADEInequality.admissible_A' theorem admissible_D' (n : ℕ+) : Admissible (D' n) := Or.inr <| Or.inl ⟨n, rfl⟩ #align ADE_inequality.admissible_D' ADEInequality.admissible_D' theorem admissible_E'3 : Admissible (E' 3) := Or.inr <| Or.inr <| Or.inl rfl #align ADE_inequality.admissible_E'3 ADEInequality.admissible_E'3 theorem admissible_E'4 : Admissible (E' 4) := Or.inr <| Or.inr <| Or.inr <| Or.inl rfl #align ADE_inequality.admissible_E'4 ADEInequality.admissible_E'4 theorem admissible_E'5 : Admissible (E' 5) := Or.inr <| Or.inr <| Or.inr <| Or.inr rfl #align ADE_inequality.admissible_E'5 ADEInequality.admissible_E'5 theorem admissible_E6 : Admissible E6 := admissible_E'3 #align ADE_inequality.admissible_E6 ADEInequality.admissible_E6 theorem admissible_E7 : Admissible E7 := admissible_E'4 #align ADE_inequality.admissible_E7 ADEInequality.admissible_E7 theorem admissible_E8 : Admissible E8 := admissible_E'5 #align ADE_inequality.admissible_E8 ADEInequality.admissible_E8 theorem Admissible.one_lt_sumInv {pqr : Multiset ℕ+} : Admissible pqr → 1 < sumInv pqr := by rw [Admissible] rintro (⟨p', q', H⟩ | ⟨n, H⟩ | H | H | H) · rw [← H, A', sumInv_pqr, add_assoc] simp only [lt_add_iff_pos_right, PNat.one_coe, inv_one, Nat.cast_one] apply add_pos <;> simp only [PNat.pos, Nat.cast_pos, inv_pos] · rw [← H, D', sumInv_pqr] conv_rhs => simp only [OfNat.ofNat, PNat.mk_coe] norm_num all_goals rw [← H, E', sumInv_pqr] conv_rhs => simp only [OfNat.ofNat, PNat.mk_coe] rfl #align ADE_inequality.admissible.one_lt_sum_inv ADEInequality.Admissible.one_lt_sumInv theorem lt_three {p q r : ℕ+} (hpq : p ≤ q) (hqr : q ≤ r) (H : 1 < sumInv {p, q, r}) : p < 3 := by have h3 : (0 : ℚ) < 3 := by norm_num contrapose! H rw [sumInv_pqr] have h3q := H.trans hpq have h3r := h3q.trans hqr have hp: (p : ℚ)⁻¹ ≤ 3⁻¹ := by rw [inv_le_inv _ h3] · assumption_mod_cast · norm_num have hq: (q : ℚ)⁻¹ ≤ 3⁻¹ := by rw [inv_le_inv _ h3] · assumption_mod_cast · norm_num have hr: (r : ℚ)⁻¹ ≤ 3⁻¹ := by rw [inv_le_inv _ h3] · assumption_mod_cast · norm_num calc (p : ℚ)⁻¹ + (q : ℚ)⁻¹ + (r : ℚ)⁻¹ ≤ 3⁻¹ + 3⁻¹ + 3⁻¹ := add_le_add (add_le_add hp hq) hr _ = 1 := by norm_num #align ADE_inequality.lt_three ADEInequality.lt_three
Mathlib/NumberTheory/ADEInequality.lean
198
213
theorem lt_four {q r : ℕ+} (hqr : q ≤ r) (H : 1 < sumInv {2, q, r}) : q < 4 := by
have h4 : (0 : ℚ) < 4 := by norm_num contrapose! H rw [sumInv_pqr] have h4r := H.trans hqr have hq: (q : ℚ)⁻¹ ≤ 4⁻¹ := by rw [inv_le_inv _ h4] · assumption_mod_cast · norm_num have hr: (r : ℚ)⁻¹ ≤ 4⁻¹ := by rw [inv_le_inv _ h4] · assumption_mod_cast · norm_num calc (2⁻¹ + (q : ℚ)⁻¹ + (r : ℚ)⁻¹) ≤ 2⁻¹ + 4⁻¹ + 4⁻¹ := add_le_add (add_le_add le_rfl hq) hr _ = 1 := by norm_num
import Mathlib.Order.Filter.CountableInter set_option autoImplicit true open Function Set Filter class HasCountableSeparatingOn (α : Type*) (p : Set α → Prop) (t : Set α) : Prop where exists_countable_separating : ∃ S : Set (Set α), S.Countable ∧ (∀ s ∈ S, p s) ∧ ∀ x ∈ t, ∀ y ∈ t, (∀ s ∈ S, x ∈ s ↔ y ∈ s) → x = y theorem exists_countable_separating (α : Type*) (p : Set α → Prop) (t : Set α) [h : HasCountableSeparatingOn α p t] : ∃ S : Set (Set α), S.Countable ∧ (∀ s ∈ S, p s) ∧ ∀ x ∈ t, ∀ y ∈ t, (∀ s ∈ S, x ∈ s ↔ y ∈ s) → x = y := h.1 theorem exists_nonempty_countable_separating (α : Type*) {p : Set α → Prop} {s₀} (hp : p s₀) (t : Set α) [HasCountableSeparatingOn α p t] : ∃ S : Set (Set α), S.Nonempty ∧ S.Countable ∧ (∀ s ∈ S, p s) ∧ ∀ x ∈ t, ∀ y ∈ t, (∀ s ∈ S, x ∈ s ↔ y ∈ s) → x = y := let ⟨S, hSc, hSp, hSt⟩ := exists_countable_separating α p t ⟨insert s₀ S, insert_nonempty _ _, hSc.insert _, forall_insert_of_forall hSp hp, fun x hx y hy hxy ↦ hSt x hx y hy <| forall_of_forall_insert hxy⟩ theorem exists_seq_separating (α : Type*) {p : Set α → Prop} {s₀} (hp : p s₀) (t : Set α) [HasCountableSeparatingOn α p t] : ∃ S : ℕ → Set α, (∀ n, p (S n)) ∧ ∀ x ∈ t, ∀ y ∈ t, (∀ n, x ∈ S n ↔ y ∈ S n) → x = y := by rcases exists_nonempty_countable_separating α hp t with ⟨S, hSne, hSc, hS⟩ rcases hSc.exists_eq_range hSne with ⟨S, rfl⟩ use S simpa only [forall_mem_range] using hS theorem HasCountableSeparatingOn.mono {α} {p₁ p₂ : Set α → Prop} {t₁ t₂ : Set α} [h : HasCountableSeparatingOn α p₁ t₁] (hp : ∀ s, p₁ s → p₂ s) (ht : t₂ ⊆ t₁) : HasCountableSeparatingOn α p₂ t₂ where exists_countable_separating := let ⟨S, hSc, hSp, hSt⟩ := h.1 ⟨S, hSc, fun s hs ↦ hp s (hSp s hs), fun x hx y hy ↦ hSt x (ht hx) y (ht hy)⟩ theorem HasCountableSeparatingOn.of_subtype {α : Type*} {p : Set α → Prop} {t : Set α} {q : Set t → Prop} [h : HasCountableSeparatingOn t q univ] (hpq : ∀ U, q U → ∃ V, p V ∧ (↑) ⁻¹' V = U) : HasCountableSeparatingOn α p t := by rcases h.1 with ⟨S, hSc, hSq, hS⟩ choose! V hpV hV using fun s hs ↦ hpq s (hSq s hs) refine ⟨⟨V '' S, hSc.image _, forall_mem_image.2 hpV, fun x hx y hy h ↦ ?_⟩⟩ refine congr_arg Subtype.val (hS ⟨x, hx⟩ trivial ⟨y, hy⟩ trivial fun U hU ↦ ?_) rw [← hV U hU] exact h _ (mem_image_of_mem _ hU)
Mathlib/Order/Filter/CountableSeparatingOn.lean
128
139
theorem HasCountableSeparatingOn.subtype_iff {α : Type*} {p : Set α → Prop} {t : Set α} : HasCountableSeparatingOn t (fun u ↦ ∃ v, p v ∧ (↑) ⁻¹' v = u) univ ↔ HasCountableSeparatingOn α p t := by
constructor <;> intro h · exact h.of_subtype $ fun s ↦ id rcases h with ⟨S, Sct, Sp, hS⟩ use {Subtype.val ⁻¹' s | s ∈ S}, Sct.image _, ?_, ?_ · rintro u ⟨t, tS, rfl⟩ exact ⟨t, Sp _ tS, rfl⟩ rintro x - y - hxy exact Subtype.val_injective $ hS _ (Subtype.coe_prop _) _ (Subtype.coe_prop _) fun s hs ↦ hxy (Subtype.val ⁻¹' s) ⟨s, hs, rfl⟩
import Mathlib.AlgebraicGeometry.AffineScheme import Mathlib.AlgebraicGeometry.Pullbacks import Mathlib.CategoryTheory.MorphismProperty.Limits import Mathlib.Data.List.TFAE #align_import algebraic_geometry.morphisms.basic from "leanprover-community/mathlib"@"434e2fd21c1900747afc6d13d8be7f4eedba7218" set_option linter.uppercaseLean3 false universe u open TopologicalSpace CategoryTheory CategoryTheory.Limits Opposite noncomputable section namespace AlgebraicGeometry def AffineTargetMorphismProperty := ∀ ⦃X Y : Scheme⦄ (_ : X ⟶ Y) [IsAffine Y], Prop #align algebraic_geometry.affine_target_morphism_property AlgebraicGeometry.AffineTargetMorphismProperty protected def Scheme.isIso : MorphismProperty Scheme := @IsIso Scheme _ #align algebraic_geometry.Scheme.is_iso AlgebraicGeometry.Scheme.isIso protected def Scheme.affineTargetIsIso : AffineTargetMorphismProperty := fun _ _ f _ => IsIso f #align algebraic_geometry.Scheme.affine_target_is_iso AlgebraicGeometry.Scheme.affineTargetIsIso instance : Inhabited AffineTargetMorphismProperty := ⟨Scheme.affineTargetIsIso⟩ def AffineTargetMorphismProperty.toProperty (P : AffineTargetMorphismProperty) : MorphismProperty Scheme := fun _ _ f => ∃ h, @P _ _ f h #align algebraic_geometry.affine_target_morphism_property.to_property AlgebraicGeometry.AffineTargetMorphismProperty.toProperty theorem AffineTargetMorphismProperty.toProperty_apply (P : AffineTargetMorphismProperty) {X Y : Scheme} (f : X ⟶ Y) [i : IsAffine Y] : P.toProperty f ↔ P f := by delta AffineTargetMorphismProperty.toProperty; simp [*] #align algebraic_geometry.affine_target_morphism_property.to_property_apply AlgebraicGeometry.AffineTargetMorphismProperty.toProperty_apply theorem affine_cancel_left_isIso {P : AffineTargetMorphismProperty} (hP : P.toProperty.RespectsIso) {X Y Z : Scheme} (f : X ⟶ Y) (g : Y ⟶ Z) [IsIso f] [IsAffine Z] : P (f ≫ g) ↔ P g := by rw [← P.toProperty_apply, ← P.toProperty_apply, hP.cancel_left_isIso] #align algebraic_geometry.affine_cancel_left_is_iso AlgebraicGeometry.affine_cancel_left_isIso theorem affine_cancel_right_isIso {P : AffineTargetMorphismProperty} (hP : P.toProperty.RespectsIso) {X Y Z : Scheme} (f : X ⟶ Y) (g : Y ⟶ Z) [IsIso g] [IsAffine Z] [IsAffine Y] : P (f ≫ g) ↔ P f := by rw [← P.toProperty_apply, ← P.toProperty_apply, hP.cancel_right_isIso] #align algebraic_geometry.affine_cancel_right_is_iso AlgebraicGeometry.affine_cancel_right_isIso
Mathlib/AlgebraicGeometry/Morphisms/Basic.lean
109
116
theorem AffineTargetMorphismProperty.respectsIso_mk {P : AffineTargetMorphismProperty} (h₁ : ∀ {X Y Z} (e : X ≅ Y) (f : Y ⟶ Z) [IsAffine Z], P f → P (e.hom ≫ f)) (h₂ : ∀ {X Y Z} (e : Y ≅ Z) (f : X ⟶ Y) [h : IsAffine Y], P f → @P _ _ (f ≫ e.hom) (isAffineOfIso e.inv)) : P.toProperty.RespectsIso := by
constructor · rintro X Y Z e f ⟨a, h⟩; exact ⟨a, h₁ e f h⟩ · rintro X Y Z e f ⟨a, h⟩; exact ⟨isAffineOfIso e.inv, h₂ e f h⟩
import Mathlib.Analysis.Complex.Circle import Mathlib.LinearAlgebra.Determinant import Mathlib.LinearAlgebra.Matrix.GeneralLinearGroup #align_import analysis.complex.isometry from "leanprover-community/mathlib"@"ae690b0c236e488a0043f6faa8ce3546e7f2f9c5" noncomputable section open Complex open ComplexConjugate local notation "|" x "|" => Complex.abs x def rotation : circle →* ℂ ≃ₗᵢ[ℝ] ℂ where toFun a := { DistribMulAction.toLinearEquiv ℝ ℂ a with norm_map' := fun x => show |a * x| = |x| by rw [map_mul, abs_coe_circle, one_mul] } map_one' := LinearIsometryEquiv.ext <| one_smul circle map_mul' a b := LinearIsometryEquiv.ext <| mul_smul a b #align rotation rotation @[simp] theorem rotation_apply (a : circle) (z : ℂ) : rotation a z = a * z := rfl #align rotation_apply rotation_apply @[simp] theorem rotation_symm (a : circle) : (rotation a).symm = rotation a⁻¹ := LinearIsometryEquiv.ext fun _ => rfl #align rotation_symm rotation_symm @[simp] theorem rotation_trans (a b : circle) : (rotation a).trans (rotation b) = rotation (b * a) := by ext1 simp #align rotation_trans rotation_trans theorem rotation_ne_conjLIE (a : circle) : rotation a ≠ conjLIE := by intro h have h1 : rotation a 1 = conj 1 := LinearIsometryEquiv.congr_fun h 1 have hI : rotation a I = conj I := LinearIsometryEquiv.congr_fun h I rw [rotation_apply, RingHom.map_one, mul_one] at h1 rw [rotation_apply, conj_I, ← neg_one_mul, mul_left_inj' I_ne_zero, h1, eq_neg_self_iff] at hI exact one_ne_zero hI #align rotation_ne_conj_lie rotation_ne_conjLIE @[simps] def rotationOf (e : ℂ ≃ₗᵢ[ℝ] ℂ) : circle := ⟨e 1 / Complex.abs (e 1), by simp⟩ #align rotation_of rotationOf @[simp] theorem rotationOf_rotation (a : circle) : rotationOf (rotation a) = a := Subtype.ext <| by simp #align rotation_of_rotation rotationOf_rotation theorem rotation_injective : Function.Injective rotation := Function.LeftInverse.injective rotationOf_rotation #align rotation_injective rotation_injective theorem LinearIsometry.re_apply_eq_re_of_add_conj_eq (f : ℂ →ₗᵢ[ℝ] ℂ) (h₃ : ∀ z, z + conj z = f z + conj (f z)) (z : ℂ) : (f z).re = z.re := by simpa [ext_iff, add_re, add_im, conj_re, conj_im, ← two_mul, show (2 : ℝ) ≠ 0 by simp [two_ne_zero]] using (h₃ z).symm #align linear_isometry.re_apply_eq_re_of_add_conj_eq LinearIsometry.re_apply_eq_re_of_add_conj_eq
Mathlib/Analysis/Complex/Isometry.lean
96
101
theorem LinearIsometry.im_apply_eq_im_or_neg_of_re_apply_eq_re {f : ℂ →ₗᵢ[ℝ] ℂ} (h₂ : ∀ z, (f z).re = z.re) (z : ℂ) : (f z).im = z.im ∨ (f z).im = -z.im := by
have h₁ := f.norm_map z simp only [Complex.abs_def, norm_eq_abs] at h₁ rwa [Real.sqrt_inj (normSq_nonneg _) (normSq_nonneg _), normSq_apply (f z), normSq_apply z, h₂, add_left_cancel_iff, mul_self_eq_mul_self_iff] at h₁
import Batteries.Data.List.Basic import Batteries.Data.List.Lemmas open Nat namespace List section countP variable (p q : α → Bool) @[simp] theorem countP_nil : countP p [] = 0 := rfl protected theorem countP_go_eq_add (l) : countP.go p l n = n + countP.go p l 0 := by induction l generalizing n with | nil => rfl | cons head tail ih => unfold countP.go rw [ih (n := n + 1), ih (n := n), ih (n := 1)] if h : p head then simp [h, Nat.add_assoc] else simp [h] @[simp] theorem countP_cons_of_pos (l) (pa : p a) : countP p (a :: l) = countP p l + 1 := by have : countP.go p (a :: l) 0 = countP.go p l 1 := show cond .. = _ by rw [pa]; rfl unfold countP rw [this, Nat.add_comm, List.countP_go_eq_add] @[simp] theorem countP_cons_of_neg (l) (pa : ¬p a) : countP p (a :: l) = countP p l := by simp [countP, countP.go, pa] theorem countP_cons (a : α) (l) : countP p (a :: l) = countP p l + if p a then 1 else 0 := by by_cases h : p a <;> simp [h] theorem length_eq_countP_add_countP (l) : length l = countP p l + countP (fun a => ¬p a) l := by induction l with | nil => rfl | cons x h ih => if h : p x then rw [countP_cons_of_pos _ _ h, countP_cons_of_neg _ _ _, length, ih] · rw [Nat.add_assoc, Nat.add_comm _ 1, Nat.add_assoc] · simp only [h, not_true_eq_false, decide_False, not_false_eq_true] else rw [countP_cons_of_pos (fun a => ¬p a) _ _, countP_cons_of_neg _ _ h, length, ih] · rfl · simp only [h, not_false_eq_true, decide_True] theorem countP_eq_length_filter (l) : countP p l = length (filter p l) := by induction l with | nil => rfl | cons x l ih => if h : p x then rw [countP_cons_of_pos p l h, ih, filter_cons_of_pos l h, length] else rw [countP_cons_of_neg p l h, ih, filter_cons_of_neg l h]
.lake/packages/batteries/Batteries/Data/List/Count.lean
68
70
theorem countP_le_length : countP p l ≤ l.length := by
simp only [countP_eq_length_filter] apply length_filter_le
namespace Nat @[reducible] def Coprime (m n : Nat) : Prop := gcd m n = 1 instance (m n : Nat) : Decidable (Coprime m n) := inferInstanceAs (Decidable (_ = 1)) theorem coprime_iff_gcd_eq_one : Coprime m n ↔ gcd m n = 1 := .rfl theorem Coprime.gcd_eq_one : Coprime m n → gcd m n = 1 := id theorem Coprime.symm : Coprime n m → Coprime m n := (gcd_comm m n).trans theorem coprime_comm : Coprime n m ↔ Coprime m n := ⟨Coprime.symm, Coprime.symm⟩
.lake/packages/batteries/Batteries/Data/Nat/Gcd.lean
32
34
theorem Coprime.dvd_of_dvd_mul_right (H1 : Coprime k n) (H2 : k ∣ m * n) : k ∣ m := by
let t := dvd_gcd (Nat.dvd_mul_left k m) H2 rwa [gcd_mul_left, H1.gcd_eq_one, Nat.mul_one] at t
import Mathlib.CategoryTheory.Galois.GaloisObjects import Mathlib.CategoryTheory.Limits.Shapes.CombinedProducts universe u₁ u₂ w namespace CategoryTheory open Limits Functor variable {C : Type u₁} [Category.{u₂} C] namespace PreGaloisCategory variable [GaloisCategory C] section Decomposition private lemma has_decomp_connected_components_aux_conn (X : C) [IsConnected X] : ∃ (ι : Type) (f : ι → C) (g : (i : ι) → (f i) ⟶ X) (_ : IsColimit (Cofan.mk X g)), (∀ i, IsConnected (f i)) ∧ Finite ι := by refine ⟨Unit, fun _ ↦ X, fun _ ↦ 𝟙 X, mkCofanColimit _ (fun s ↦ s.inj ()), ?_⟩ exact ⟨fun _ ↦ inferInstance, inferInstance⟩ private lemma has_decomp_connected_components_aux_initial (X : C) (h : IsInitial X) : ∃ (ι : Type) (f : ι → C) (g : (i : ι) → (f i) ⟶ X) (_ : IsColimit (Cofan.mk X g)), (∀ i, IsConnected (f i)) ∧ Finite ι := by refine ⟨Empty, fun _ ↦ X, fun _ ↦ 𝟙 X, ?_⟩ use mkCofanColimit _ (fun s ↦ IsInitial.to h s.pt) (fun s ↦ by aesop) (fun s m _ ↦ IsInitial.hom_ext h m _) exact ⟨by simp only [IsEmpty.forall_iff], inferInstance⟩ private lemma has_decomp_connected_components_aux (F : C ⥤ FintypeCat.{w}) [FiberFunctor F] (n : ℕ) : ∀ (X : C), n = Nat.card (F.obj X) → ∃ (ι : Type) (f : ι → C) (g : (i : ι) → (f i) ⟶ X) (_ : IsColimit (Cofan.mk X g)), (∀ i, IsConnected (f i)) ∧ Finite ι := by induction' n using Nat.strongRecOn with n hi intro X hn by_cases h : IsConnected X · exact has_decomp_connected_components_aux_conn X by_cases nhi : IsInitial X → False · obtain ⟨Y, v, hni, hvmono, hvnoiso⟩ := has_non_trivial_subobject_of_not_isConnected_of_not_initial X h nhi obtain ⟨Z, u, ⟨c⟩⟩ := PreGaloisCategory.monoInducesIsoOnDirectSummand v let t : ColimitCocone (pair Y Z) := { cocone := BinaryCofan.mk v u, isColimit := c } have hn1 : Nat.card (F.obj Y) < n := by rw [hn] exact lt_card_fiber_of_mono_of_notIso F v hvnoiso have i : X ≅ Y ⨿ Z := (colimit.isoColimitCocone t).symm have hnn : Nat.card (F.obj X) = Nat.card (F.obj Y) + Nat.card (F.obj Z) := by rw [card_fiber_eq_of_iso F i] exact card_fiber_coprod_eq_sum F Y Z have hn2 : Nat.card (F.obj Z) < n := by rw [hn, hnn, lt_add_iff_pos_left] exact Nat.pos_of_ne_zero (non_zero_card_fiber_of_not_initial F Y hni) let ⟨ι₁, f₁, g₁, hc₁, hf₁, he₁⟩ := hi (Nat.card (F.obj Y)) hn1 Y rfl let ⟨ι₂, f₂, g₂, hc₂, hf₂, he₂⟩ := hi (Nat.card (F.obj Z)) hn2 Z rfl refine ⟨ι₁ ⊕ ι₂, Sum.elim f₁ f₂, Cofan.combPairHoms (Cofan.mk Y g₁) (Cofan.mk Z g₂) (BinaryCofan.mk v u), ?_⟩ use Cofan.combPairIsColimit hc₁ hc₂ c refine ⟨fun i ↦ ?_, inferInstance⟩ cases i · exact hf₁ _ · exact hf₂ _ · simp only [not_forall, not_false_eq_true] at nhi obtain ⟨hi⟩ := nhi exact has_decomp_connected_components_aux_initial X hi
Mathlib/CategoryTheory/Galois/Decomposition.lean
111
115
theorem has_decomp_connected_components (X : C) : ∃ (ι : Type) (f : ι → C) (g : (i : ι) → f i ⟶ X) (_ : IsColimit (Cofan.mk X g)), (∀ i, IsConnected (f i)) ∧ Finite ι := by
let F := GaloisCategory.getFiberFunctor C exact has_decomp_connected_components_aux F (Nat.card <| F.obj X) X rfl
import Mathlib.Algebra.Group.Semiconj.Defs import Mathlib.Algebra.Ring.Defs #align_import algebra.ring.semiconj from "leanprover-community/mathlib"@"70d50ecfd4900dd6d328da39ab7ebd516abe4025" universe u v w x variable {α : Type u} {β : Type v} {γ : Type w} {R : Type x} open Function namespace SemiconjBy @[simp]
Mathlib/Algebra/Ring/Semiconj.lean
33
35
theorem add_right [Distrib R] {a x y x' y' : R} (h : SemiconjBy a x y) (h' : SemiconjBy a x' y') : SemiconjBy a (x + x') (y + y') := by
simp only [SemiconjBy, left_distrib, right_distrib, h.eq, h'.eq]
import Mathlib.Algebra.Group.Units import Mathlib.Algebra.GroupWithZero.Basic import Mathlib.Logic.Equiv.Defs import Mathlib.Tactic.Contrapose import Mathlib.Tactic.Nontriviality import Mathlib.Tactic.Spread import Mathlib.Util.AssertExists #align_import algebra.group_with_zero.units.basic from "leanprover-community/mathlib"@"df5e9937a06fdd349fc60106f54b84d47b1434f0" -- Guard against import creep assert_not_exists Multiplicative assert_not_exists DenselyOrdered variable {α M₀ G₀ M₀' G₀' F F' : Type*} variable [MonoidWithZero M₀] @[simp] theorem isUnit_zero_iff : IsUnit (0 : M₀) ↔ (0 : M₀) = 1 := ⟨fun ⟨⟨_, a, (a0 : 0 * a = 1), _⟩, rfl⟩ => by rwa [zero_mul] at a0, fun h => @isUnit_of_subsingleton _ _ (subsingleton_of_zero_eq_one h) 0⟩ #align is_unit_zero_iff isUnit_zero_iff -- Porting note: removed `simp` tag because `simpNF` says it's redundant theorem not_isUnit_zero [Nontrivial M₀] : ¬IsUnit (0 : M₀) := mt isUnit_zero_iff.1 zero_ne_one #align not_is_unit_zero not_isUnit_zero namespace Ring open scoped Classical noncomputable def inverse : M₀ → M₀ := fun x => if h : IsUnit x then ((h.unit⁻¹ : M₀ˣ) : M₀) else 0 #align ring.inverse Ring.inverse @[simp] theorem inverse_unit (u : M₀ˣ) : inverse (u : M₀) = (u⁻¹ : M₀ˣ) := by rw [inverse, dif_pos u.isUnit, IsUnit.unit_of_val_units] #align ring.inverse_unit Ring.inverse_unit @[simp] theorem inverse_non_unit (x : M₀) (h : ¬IsUnit x) : inverse x = 0 := dif_neg h #align ring.inverse_non_unit Ring.inverse_non_unit
Mathlib/Algebra/GroupWithZero/Units/Basic.lean
108
110
theorem mul_inverse_cancel (x : M₀) (h : IsUnit x) : x * inverse x = 1 := by
rcases h with ⟨u, rfl⟩ rw [inverse_unit, Units.mul_inv]
import Mathlib.Algebra.IsPrimePow import Mathlib.SetTheory.Cardinal.Ordinal import Mathlib.Tactic.WLOG #align_import set_theory.cardinal.divisibility from "leanprover-community/mathlib"@"ea050b44c0f9aba9d16a948c7cc7d2e7c8493567" namespace Cardinal open Cardinal universe u variable {a b : Cardinal.{u}} {n m : ℕ} @[simp] theorem isUnit_iff : IsUnit a ↔ a = 1 := by refine ⟨fun h => ?_, by rintro rfl exact isUnit_one⟩ rcases eq_or_ne a 0 with (rfl | ha) · exact (not_isUnit_zero h).elim rw [isUnit_iff_forall_dvd] at h cases' h 1 with t ht rw [eq_comm, mul_eq_one_iff'] at ht · exact ht.1 · exact one_le_iff_ne_zero.mpr ha · apply one_le_iff_ne_zero.mpr intro h rw [h, mul_zero] at ht exact zero_ne_one ht #align cardinal.is_unit_iff Cardinal.isUnit_iff instance : Unique Cardinal.{u}ˣ where default := 1 uniq a := Units.val_eq_one.mp <| isUnit_iff.mp a.isUnit theorem le_of_dvd : ∀ {a b : Cardinal}, b ≠ 0 → a ∣ b → a ≤ b | a, x, b0, ⟨b, hab⟩ => by simpa only [hab, mul_one] using mul_le_mul_left' (one_le_iff_ne_zero.2 fun h : b = 0 => b0 (by rwa [h, mul_zero] at hab)) a #align cardinal.le_of_dvd Cardinal.le_of_dvd theorem dvd_of_le_of_aleph0_le (ha : a ≠ 0) (h : a ≤ b) (hb : ℵ₀ ≤ b) : a ∣ b := ⟨b, (mul_eq_right hb h ha).symm⟩ #align cardinal.dvd_of_le_of_aleph_0_le Cardinal.dvd_of_le_of_aleph0_le @[simp] theorem prime_of_aleph0_le (ha : ℵ₀ ≤ a) : Prime a := by refine ⟨(aleph0_pos.trans_le ha).ne', ?_, fun b c hbc => ?_⟩ · rw [isUnit_iff] exact (one_lt_aleph0.trans_le ha).ne' rcases eq_or_ne (b * c) 0 with hz | hz · rcases mul_eq_zero.mp hz with (rfl | rfl) <;> simp wlog h : c ≤ b · cases le_total c b <;> [solve_by_elim; rw [or_comm]] apply_assumption assumption' all_goals rwa [mul_comm] left have habc := le_of_dvd hz hbc rwa [mul_eq_max' <| ha.trans <| habc, max_def', if_pos h] at hbc #align cardinal.prime_of_aleph_0_le Cardinal.prime_of_aleph0_le theorem not_irreducible_of_aleph0_le (ha : ℵ₀ ≤ a) : ¬Irreducible a := by rw [irreducible_iff, not_and_or] refine Or.inr fun h => ?_ simpa [mul_aleph0_eq ha, isUnit_iff, (one_lt_aleph0.trans_le ha).ne', one_lt_aleph0.ne'] using h a ℵ₀ #align cardinal.not_irreducible_of_aleph_0_le Cardinal.not_irreducible_of_aleph0_le @[simp, norm_cast] theorem nat_coe_dvd_iff : (n : Cardinal) ∣ m ↔ n ∣ m := by refine ⟨?_, fun ⟨h, ht⟩ => ⟨h, mod_cast ht⟩⟩ rintro ⟨k, hk⟩ have : ↑m < ℵ₀ := nat_lt_aleph0 m rw [hk, mul_lt_aleph0_iff] at this rcases this with (h | h | ⟨-, hk'⟩) iterate 2 simp only [h, mul_zero, zero_mul, Nat.cast_eq_zero] at hk; simp [hk] lift k to ℕ using hk' exact ⟨k, mod_cast hk⟩ #align cardinal.nat_coe_dvd_iff Cardinal.nat_coe_dvd_iff @[simp] theorem nat_is_prime_iff : Prime (n : Cardinal) ↔ n.Prime := by simp only [Prime, Nat.prime_iff] refine and_congr (by simp) (and_congr ?_ ⟨fun h b c hbc => ?_, fun h b c hbc => ?_⟩) · simp only [isUnit_iff, Nat.isUnit_iff] exact mod_cast Iff.rfl · exact mod_cast h b c (mod_cast hbc) cases' lt_or_le (b * c) ℵ₀ with h' h' · rcases mul_lt_aleph0_iff.mp h' with (rfl | rfl | ⟨hb, hc⟩) · simp · simp lift b to ℕ using hb lift c to ℕ using hc exact mod_cast h b c (mod_cast hbc) rcases aleph0_le_mul_iff.mp h' with ⟨hb, hc, hℵ₀⟩ have hn : (n : Cardinal) ≠ 0 := by intro h rw [h, zero_dvd_iff, mul_eq_zero] at hbc cases hbc <;> contradiction wlog hℵ₀b : ℵ₀ ≤ b apply (this h c b _ _ hc hb hℵ₀.symm hn (hℵ₀.resolve_left hℵ₀b)).symm <;> try assumption · rwa [mul_comm] at hbc · rwa [mul_comm] at h' · exact Or.inl (dvd_of_le_of_aleph0_le hn ((nat_lt_aleph0 n).le.trans hℵ₀b) hℵ₀b) #align cardinal.nat_is_prime_iff Cardinal.nat_is_prime_iff
Mathlib/SetTheory/Cardinal/Divisibility.lean
137
141
theorem is_prime_iff {a : Cardinal} : Prime a ↔ ℵ₀ ≤ a ∨ ∃ p : ℕ, a = p ∧ p.Prime := by
rcases le_or_lt ℵ₀ a with h | h · simp [h] lift a to ℕ using id h simp [not_le.mpr h]
import Mathlib.Logic.Encodable.Basic import Mathlib.Logic.Pairwise import Mathlib.Data.Set.Subsingleton #align_import logic.encodable.lattice from "leanprover-community/mathlib"@"9003f28797c0664a49e4179487267c494477d853" open Set namespace Encodable variable {α : Type*} {β : Type*} [Encodable β] theorem iSup_decode₂ [CompleteLattice α] (f : β → α) : ⨆ (i : ℕ) (b ∈ decode₂ β i), f b = (⨆ b, f b) := by rw [iSup_comm] simp only [mem_decode₂, iSup_iSup_eq_right] #align encodable.supr_decode₂ Encodable.iSup_decode₂ theorem iUnion_decode₂ (f : β → Set α) : ⋃ (i : ℕ) (b ∈ decode₂ β i), f b = ⋃ b, f b := iSup_decode₂ f #align encodable.Union_decode₂ Encodable.iUnion_decode₂ --@[elab_as_elim] theorem iUnion_decode₂_cases {f : β → Set α} {C : Set α → Prop} (H0 : C ∅) (H1 : ∀ b, C (f b)) {n} : C (⋃ b ∈ decode₂ β n, f b) := match decode₂ β n with | none => by simp only [Option.mem_def, iUnion_of_empty, iUnion_empty] apply H0 | some b => by convert H1 b simp [ext_iff] #align encodable.Union_decode₂_cases Encodable.iUnion_decode₂_cases
Mathlib/Logic/Encodable/Lattice.lean
53
59
theorem iUnion_decode₂_disjoint_on {f : β → Set α} (hd : Pairwise (Disjoint on f)) : Pairwise (Disjoint on fun i => ⋃ b ∈ decode₂ β i, f b) := by
rintro i j ij refine disjoint_left.mpr fun x => ?_ suffices ∀ a, encode a = i → x ∈ f a → ∀ b, encode b = j → x ∉ f b by simpa [decode₂_eq_some] rintro a rfl ha b rfl hb exact (hd (mt (congr_arg encode) ij)).le_bot ⟨ha, hb⟩
import Mathlib.RingTheory.FractionalIdeal.Basic import Mathlib.RingTheory.Ideal.Norm namespace FractionalIdeal open scoped Pointwise nonZeroDivisors variable {R : Type*} [CommRing R] [IsDedekindDomain R] [Module.Free ℤ R] [Module.Finite ℤ R] variable {K : Type*} [CommRing K] [Algebra R K] [IsFractionRing R K]
Mathlib/RingTheory/FractionalIdeal/Norm.lean
36
51
theorem absNorm_div_norm_eq_absNorm_div_norm {I : FractionalIdeal R⁰ K} (a : R⁰) (I₀ : Ideal R) (h : a • (I : Submodule R K) = Submodule.map (Algebra.linearMap R K) I₀) : (Ideal.absNorm I.num : ℚ) / |Algebra.norm ℤ (I.den:R)| = (Ideal.absNorm I₀ : ℚ) / |Algebra.norm ℤ (a:R)| := by
rw [div_eq_div_iff] · replace h := congr_arg (I.den • ·) h have h' := congr_arg (a • ·) (den_mul_self_eq_num I) dsimp only at h h' rw [smul_comm] at h rw [h, Submonoid.smul_def, Submonoid.smul_def, ← Submodule.ideal_span_singleton_smul, ← Submodule.ideal_span_singleton_smul, ← Submodule.map_smul'', ← Submodule.map_smul'', (LinearMap.map_injective ?_).eq_iff, smul_eq_mul, smul_eq_mul] at h' · simp_rw [← Int.cast_natAbs, ← Nat.cast_mul, ← Ideal.absNorm_span_singleton] rw [← _root_.map_mul, ← _root_.map_mul, mul_comm, ← h', mul_comm] · exact LinearMap.ker_eq_bot.mpr (IsFractionRing.injective R K) all_goals simpa [Algebra.norm_eq_zero_iff] using nonZeroDivisors.coe_ne_zero _
import Mathlib.LinearAlgebra.Dual import Mathlib.LinearAlgebra.Matrix.ToLin #align_import linear_algebra.contraction from "leanprover-community/mathlib"@"657df4339ae6ceada048c8a2980fb10e393143ec" suppress_compilation -- Porting note: universe metavariables behave oddly universe w u v₁ v₂ v₃ v₄ variable {ι : Type w} (R : Type u) (M : Type v₁) (N : Type v₂) (P : Type v₃) (Q : Type v₄) -- Porting note: we need high priority for this to fire first; not the case in ML3 attribute [local ext high] TensorProduct.ext section Contraction open TensorProduct LinearMap Matrix Module open TensorProduct section CommSemiring variable [CommSemiring R] variable [AddCommMonoid M] [AddCommMonoid N] [AddCommMonoid P] [AddCommMonoid Q] variable [Module R M] [Module R N] [Module R P] [Module R Q] variable [DecidableEq ι] [Fintype ι] (b : Basis ι R M) -- Porting note: doesn't like implicit ring in the tensor product def contractLeft : Module.Dual R M ⊗[R] M →ₗ[R] R := (uncurry _ _ _ _).toFun LinearMap.id #align contract_left contractLeft -- Porting note: doesn't like implicit ring in the tensor product def contractRight : M ⊗[R] Module.Dual R M →ₗ[R] R := (uncurry _ _ _ _).toFun (LinearMap.flip LinearMap.id) #align contract_right contractRight -- Porting note: doesn't like implicit ring in the tensor product def dualTensorHom : Module.Dual R M ⊗[R] N →ₗ[R] M →ₗ[R] N := let M' := Module.Dual R M (uncurry R M' N (M →ₗ[R] N) : _ → M' ⊗ N →ₗ[R] M →ₗ[R] N) LinearMap.smulRightₗ #align dual_tensor_hom dualTensorHom variable {R M N P Q} @[simp] theorem contractLeft_apply (f : Module.Dual R M) (m : M) : contractLeft R M (f ⊗ₜ m) = f m := rfl #align contract_left_apply contractLeft_apply @[simp] theorem contractRight_apply (f : Module.Dual R M) (m : M) : contractRight R M (m ⊗ₜ f) = f m := rfl #align contract_right_apply contractRight_apply @[simp] theorem dualTensorHom_apply (f : Module.Dual R M) (m : M) (n : N) : dualTensorHom R M N (f ⊗ₜ n) m = f m • n := rfl #align dual_tensor_hom_apply dualTensorHom_apply @[simp] theorem transpose_dualTensorHom (f : Module.Dual R M) (m : M) : Dual.transpose (R := R) (dualTensorHom R M M (f ⊗ₜ m)) = dualTensorHom R _ _ (Dual.eval R M m ⊗ₜ f) := by ext f' m' simp only [Dual.transpose_apply, coe_comp, Function.comp_apply, dualTensorHom_apply, LinearMap.map_smulₛₗ, RingHom.id_apply, Algebra.id.smul_eq_mul, Dual.eval_apply, LinearMap.smul_apply] exact mul_comm _ _ #align transpose_dual_tensor_hom transpose_dualTensorHom @[simp] theorem dualTensorHom_prodMap_zero (f : Module.Dual R M) (p : P) : ((dualTensorHom R M P) (f ⊗ₜ[R] p)).prodMap (0 : N →ₗ[R] Q) = dualTensorHom R (M × N) (P × Q) ((f ∘ₗ fst R M N) ⊗ₜ inl R P Q p) := by ext <;> simp only [coe_comp, coe_inl, Function.comp_apply, prodMap_apply, dualTensorHom_apply, fst_apply, Prod.smul_mk, LinearMap.zero_apply, smul_zero] #align dual_tensor_hom_prod_map_zero dualTensorHom_prodMap_zero @[simp] theorem zero_prodMap_dualTensorHom (g : Module.Dual R N) (q : Q) : (0 : M →ₗ[R] P).prodMap ((dualTensorHom R N Q) (g ⊗ₜ[R] q)) = dualTensorHom R (M × N) (P × Q) ((g ∘ₗ snd R M N) ⊗ₜ inr R P Q q) := by ext <;> simp only [coe_comp, coe_inr, Function.comp_apply, prodMap_apply, dualTensorHom_apply, snd_apply, Prod.smul_mk, LinearMap.zero_apply, smul_zero] #align zero_prod_map_dual_tensor_hom zero_prodMap_dualTensorHom theorem map_dualTensorHom (f : Module.Dual R M) (p : P) (g : Module.Dual R N) (q : Q) : TensorProduct.map (dualTensorHom R M P (f ⊗ₜ[R] p)) (dualTensorHom R N Q (g ⊗ₜ[R] q)) = dualTensorHom R (M ⊗[R] N) (P ⊗[R] Q) (dualDistrib R M N (f ⊗ₜ g) ⊗ₜ[R] p ⊗ₜ[R] q) := by ext m n simp only [compr₂_apply, mk_apply, map_tmul, dualTensorHom_apply, dualDistrib_apply, ← smul_tmul_smul] #align map_dual_tensor_hom map_dualTensorHom @[simp] theorem comp_dualTensorHom (f : Module.Dual R M) (n : N) (g : Module.Dual R N) (p : P) : dualTensorHom R N P (g ⊗ₜ[R] p) ∘ₗ dualTensorHom R M N (f ⊗ₜ[R] n) = g n • dualTensorHom R M P (f ⊗ₜ p) := by ext m simp only [coe_comp, Function.comp_apply, dualTensorHom_apply, LinearMap.map_smul, RingHom.id_apply, LinearMap.smul_apply] rw [smul_comm] #align comp_dual_tensor_hom comp_dualTensorHom
Mathlib/LinearAlgebra/Contraction.lean
133
140
theorem toMatrix_dualTensorHom {m : Type*} {n : Type*} [Fintype m] [Finite n] [DecidableEq m] [DecidableEq n] (bM : Basis m R M) (bN : Basis n R N) (j : m) (i : n) : toMatrix bM bN (dualTensorHom R M N (bM.coord j ⊗ₜ bN i)) = stdBasisMatrix i j 1 := by
ext i' j' by_cases hij : i = i' ∧ j = j' <;> simp [LinearMap.toMatrix_apply, Finsupp.single_eq_pi_single, hij] rw [and_iff_not_or_not, Classical.not_not] at hij cases' hij with hij hij <;> simp [hij]
import Mathlib.Data.Set.Subsingleton import Mathlib.Order.WithBot #align_import data.set.image from "leanprover-community/mathlib"@"001ffdc42920050657fd45bd2b8bfbec8eaaeb29" universe u v open Function Set namespace Set variable {α β γ : Type*} {ι ι' : Sort*} section Preimage variable {f : α → β} {g : β → γ} @[simp] theorem preimage_empty : f ⁻¹' ∅ = ∅ := rfl #align set.preimage_empty Set.preimage_empty
Mathlib/Data/Set/Image.lean
53
55
theorem preimage_congr {f g : α → β} {s : Set β} (h : ∀ x : α, f x = g x) : f ⁻¹' s = g ⁻¹' s := by
congr with x simp [h]
import Mathlib.Algebra.Star.Basic import Mathlib.Data.Set.Finite import Mathlib.Data.Set.Pointwise.Basic #align_import algebra.star.pointwise from "leanprover-community/mathlib"@"30413fc89f202a090a54d78e540963ed3de0056e" namespace Set open Pointwise local postfix:max "⋆" => star variable {α : Type*} {s t : Set α} {a : α} protected def star [Star α] : Star (Set α) := ⟨preimage Star.star⟩ #align set.has_star Set.star scoped[Pointwise] attribute [instance] Set.star @[simp] theorem star_empty [Star α] : (∅ : Set α)⋆ = ∅ := rfl #align set.star_empty Set.star_empty @[simp] theorem star_univ [Star α] : (univ : Set α)⋆ = univ := rfl #align set.star_univ Set.star_univ @[simp] theorem nonempty_star [InvolutiveStar α] {s : Set α} : s⋆.Nonempty ↔ s.Nonempty := star_involutive.surjective.nonempty_preimage #align set.nonempty_star Set.nonempty_star theorem Nonempty.star [InvolutiveStar α] {s : Set α} (h : s.Nonempty) : s⋆.Nonempty := nonempty_star.2 h #align set.nonempty.star Set.Nonempty.star @[simp] theorem mem_star [Star α] : a ∈ s⋆ ↔ a⋆ ∈ s := Iff.rfl #align set.mem_star Set.mem_star theorem star_mem_star [InvolutiveStar α] : a⋆ ∈ s⋆ ↔ a ∈ s := by simp only [mem_star, star_star] #align set.star_mem_star Set.star_mem_star @[simp] theorem star_preimage [Star α] : Star.star ⁻¹' s = s⋆ := rfl #align set.star_preimage Set.star_preimage @[simp] theorem image_star [InvolutiveStar α] : Star.star '' s = s⋆ := by simp only [← star_preimage] rw [image_eq_preimage_of_inverse] <;> intro <;> simp only [star_star] #align set.image_star Set.image_star @[simp] theorem inter_star [Star α] : (s ∩ t)⋆ = s⋆ ∩ t⋆ := preimage_inter #align set.inter_star Set.inter_star @[simp] theorem union_star [Star α] : (s ∪ t)⋆ = s⋆ ∪ t⋆ := preimage_union #align set.union_star Set.union_star @[simp] theorem iInter_star {ι : Sort*} [Star α] (s : ι → Set α) : (⋂ i, s i)⋆ = ⋂ i, (s i)⋆ := preimage_iInter #align set.Inter_star Set.iInter_star @[simp] theorem iUnion_star {ι : Sort*} [Star α] (s : ι → Set α) : (⋃ i, s i)⋆ = ⋃ i, (s i)⋆ := preimage_iUnion #align set.Union_star Set.iUnion_star @[simp] theorem compl_star [Star α] : sᶜ⋆ = s⋆ᶜ := preimage_compl #align set.compl_star Set.compl_star @[simp] instance [InvolutiveStar α] : InvolutiveStar (Set α) where star := Star.star star_involutive s := by simp only [← star_preimage, preimage_preimage, star_star, preimage_id'] @[simp] theorem star_subset_star [InvolutiveStar α] {s t : Set α} : s⋆ ⊆ t⋆ ↔ s ⊆ t := Equiv.star.surjective.preimage_subset_preimage_iff #align set.star_subset_star Set.star_subset_star
Mathlib/Algebra/Star/Pointwise.lean
107
108
theorem star_subset [InvolutiveStar α] {s t : Set α} : s⋆ ⊆ t ↔ s ⊆ t⋆ := by
rw [← star_subset_star, star_star]
import Mathlib.Analysis.NormedSpace.Exponential import Mathlib.Analysis.NormedSpace.ProdLp import Mathlib.Topology.Instances.TrivSqZeroExt #align_import analysis.normed_space.triv_sq_zero_ext from "leanprover-community/mathlib"@"88a563b158f59f2983cfad685664da95502e8cdd" variable (𝕜 : Type*) {S R M : Type*} local notation "tsze" => TrivSqZeroExt open NormedSpace -- For `exp`. namespace TrivSqZeroExt section Topology section Ring variable [Field 𝕜] [CharZero 𝕜] [Ring R] [AddCommGroup M] [Algebra 𝕜 R] [Module 𝕜 M] [Module R M] [Module Rᵐᵒᵖ M] [SMulCommClass R Rᵐᵒᵖ M] [IsScalarTower 𝕜 R M] [IsScalarTower 𝕜 Rᵐᵒᵖ M] [TopologicalSpace R] [TopologicalSpace M] [TopologicalRing R] [TopologicalAddGroup M] [ContinuousSMul R M] [ContinuousSMul Rᵐᵒᵖ M]
Mathlib/Analysis/NormedSpace/TrivSqZeroExt.lean
83
88
theorem snd_expSeries_of_smul_comm (x : tsze R M) (hx : MulOpposite.op x.fst • x.snd = x.fst • x.snd) (n : ℕ) : snd (expSeries 𝕜 (tsze R M) (n + 1) fun _ => x) = (expSeries 𝕜 R n fun _ => x.fst) • x.snd := by
simp_rw [expSeries_apply_eq, snd_smul, snd_pow_of_smul_comm _ _ hx, nsmul_eq_smul_cast 𝕜 (n + 1), smul_smul, smul_assoc, Nat.factorial_succ, Nat.pred_succ, Nat.cast_mul, mul_inv_rev, inv_mul_cancel_right₀ ((Nat.cast_ne_zero (R := 𝕜)).mpr <| Nat.succ_ne_zero n)]
import Mathlib.Algebra.Group.Subgroup.Basic import Mathlib.Data.Fintype.Basic import Mathlib.Data.List.Sublists import Mathlib.Data.List.InsertNth #align_import group_theory.free_group from "leanprover-community/mathlib"@"f93c11933efbc3c2f0299e47b8ff83e9b539cbf6" open Relation universe u v w variable {α : Type u} attribute [local simp] List.append_eq_has_append -- Porting note: to_additive.map_namespace is not supported yet -- worked around it by putting a few extra manual mappings (but not too many all in all) -- run_cmd to_additive.map_namespace `FreeGroup `FreeAddGroup inductive FreeAddGroup.Red.Step : List (α × Bool) → List (α × Bool) → Prop | not {L₁ L₂ x b} : FreeAddGroup.Red.Step (L₁ ++ (x, b) :: (x, not b) :: L₂) (L₁ ++ L₂) #align free_add_group.red.step FreeAddGroup.Red.Step attribute [simp] FreeAddGroup.Red.Step.not @[to_additive FreeAddGroup.Red.Step] inductive FreeGroup.Red.Step : List (α × Bool) → List (α × Bool) → Prop | not {L₁ L₂ x b} : FreeGroup.Red.Step (L₁ ++ (x, b) :: (x, not b) :: L₂) (L₁ ++ L₂) #align free_group.red.step FreeGroup.Red.Step attribute [simp] FreeGroup.Red.Step.not namespace FreeGroup variable {L L₁ L₂ L₃ L₄ : List (α × Bool)} @[to_additive FreeAddGroup.Red "Reflexive-transitive closure of `Red.Step`"] def Red : List (α × Bool) → List (α × Bool) → Prop := ReflTransGen Red.Step #align free_group.red FreeGroup.Red #align free_add_group.red FreeAddGroup.Red @[to_additive (attr := refl)] theorem Red.refl : Red L L := ReflTransGen.refl #align free_group.red.refl FreeGroup.Red.refl #align free_add_group.red.refl FreeAddGroup.Red.refl @[to_additive (attr := trans)] theorem Red.trans : Red L₁ L₂ → Red L₂ L₃ → Red L₁ L₃ := ReflTransGen.trans #align free_group.red.trans FreeGroup.Red.trans #align free_add_group.red.trans FreeAddGroup.Red.trans namespace Red @[to_additive "Predicate asserting that the word `w₁` can be reduced to `w₂` in one step, i.e. there are words `w₃ w₄` and letter `x` such that `w₁ = w₃ + x + (-x) + w₄` and `w₂ = w₃w₄`"] theorem Step.length : ∀ {L₁ L₂ : List (α × Bool)}, Step L₁ L₂ → L₂.length + 2 = L₁.length | _, _, @Red.Step.not _ L1 L2 x b => by rw [List.length_append, List.length_append]; rfl #align free_group.red.step.length FreeGroup.Red.Step.length #align free_add_group.red.step.length FreeAddGroup.Red.Step.length @[to_additive (attr := simp)] theorem Step.not_rev {x b} : Step (L₁ ++ (x, !b) :: (x, b) :: L₂) (L₁ ++ L₂) := by cases b <;> exact Step.not #align free_group.red.step.bnot_rev FreeGroup.Red.Step.not_rev #align free_add_group.red.step.bnot_rev FreeAddGroup.Red.Step.not_rev @[to_additive (attr := simp)] theorem Step.cons_not {x b} : Red.Step ((x, b) :: (x, !b) :: L) L := @Step.not _ [] _ _ _ #align free_group.red.step.cons_bnot FreeGroup.Red.Step.cons_not #align free_add_group.red.step.cons_bnot FreeAddGroup.Red.Step.cons_not @[to_additive (attr := simp)] theorem Step.cons_not_rev {x b} : Red.Step ((x, !b) :: (x, b) :: L) L := @Red.Step.not_rev _ [] _ _ _ #align free_group.red.step.cons_bnot_rev FreeGroup.Red.Step.cons_not_rev #align free_add_group.red.step.cons_bnot_rev FreeAddGroup.Red.Step.cons_not_rev @[to_additive] theorem Step.append_left : ∀ {L₁ L₂ L₃ : List (α × Bool)}, Step L₂ L₃ → Step (L₁ ++ L₂) (L₁ ++ L₃) | _, _, _, Red.Step.not => by rw [← List.append_assoc, ← List.append_assoc]; constructor #align free_group.red.step.append_left FreeGroup.Red.Step.append_left #align free_add_group.red.step.append_left FreeAddGroup.Red.Step.append_left @[to_additive] theorem Step.cons {x} (H : Red.Step L₁ L₂) : Red.Step (x :: L₁) (x :: L₂) := @Step.append_left _ [x] _ _ H #align free_group.red.step.cons FreeGroup.Red.Step.cons #align free_add_group.red.step.cons FreeAddGroup.Red.Step.cons @[to_additive] theorem Step.append_right : ∀ {L₁ L₂ L₃ : List (α × Bool)}, Step L₁ L₂ → Step (L₁ ++ L₃) (L₂ ++ L₃) | _, _, _, Red.Step.not => by simp #align free_group.red.step.append_right FreeGroup.Red.Step.append_right #align free_add_group.red.step.append_right FreeAddGroup.Red.Step.append_right @[to_additive] theorem not_step_nil : ¬Step [] L := by generalize h' : [] = L' intro h cases' h with L₁ L₂ simp [List.nil_eq_append] at h' #align free_group.red.not_step_nil FreeGroup.Red.not_step_nil #align free_add_group.red.not_step_nil FreeAddGroup.Red.not_step_nil @[to_additive]
Mathlib/GroupTheory/FreeGroup/Basic.lean
160
173
theorem Step.cons_left_iff {a : α} {b : Bool} : Step ((a, b) :: L₁) L₂ ↔ (∃ L, Step L₁ L ∧ L₂ = (a, b) :: L) ∨ L₁ = (a, ! b) :: L₂ := by
constructor · generalize hL : ((a, b) :: L₁ : List _) = L rintro @⟨_ | ⟨p, s'⟩, e, a', b'⟩ · simp at hL simp [*] · simp at hL rcases hL with ⟨rfl, rfl⟩ refine Or.inl ⟨s' ++ e, Step.not, ?_⟩ simp · rintro (⟨L, h, rfl⟩ | rfl) · exact Step.cons h · exact Step.cons_not
import Mathlib.GroupTheory.Submonoid.Inverses import Mathlib.RingTheory.FiniteType import Mathlib.RingTheory.Localization.Basic #align_import ring_theory.localization.inv_submonoid from "leanprover-community/mathlib"@"6e7ca692c98bbf8a64868f61a67fb9c33b10770d" variable {R : Type*} [CommRing R] (M : Submonoid R) (S : Type*) [CommRing S] variable [Algebra R S] {P : Type*} [CommRing P] open Function namespace IsLocalization section InvSubmonoid def invSubmonoid : Submonoid S := (M.map (algebraMap R S)).leftInv #align is_localization.inv_submonoid IsLocalization.invSubmonoid variable [IsLocalization M S] theorem submonoid_map_le_is_unit : M.map (algebraMap R S) ≤ IsUnit.submonoid S := by rintro _ ⟨a, ha, rfl⟩ exact IsLocalization.map_units S ⟨_, ha⟩ #align is_localization.submonoid_map_le_is_unit IsLocalization.submonoid_map_le_is_unit noncomputable abbrev equivInvSubmonoid : M.map (algebraMap R S) ≃* invSubmonoid M S := ((M.map (algebraMap R S)).leftInvEquiv (submonoid_map_le_is_unit M S)).symm #align is_localization.equiv_inv_submonoid IsLocalization.equivInvSubmonoid noncomputable def toInvSubmonoid : M →* invSubmonoid M S := (equivInvSubmonoid M S).toMonoidHom.comp ((algebraMap R S : R →* S).submonoidMap M) #align is_localization.to_inv_submonoid IsLocalization.toInvSubmonoid theorem toInvSubmonoid_surjective : Function.Surjective (toInvSubmonoid M S) := Function.Surjective.comp (β := M.map (algebraMap R S)) (Equiv.surjective (equivInvSubmonoid _ _).toEquiv) (MonoidHom.submonoidMap_surjective _ _) #align is_localization.to_inv_submonoid_surjective IsLocalization.toInvSubmonoid_surjective @[simp] theorem toInvSubmonoid_mul (m : M) : (toInvSubmonoid M S m : S) * algebraMap R S m = 1 := Submonoid.leftInvEquiv_symm_mul _ (submonoid_map_le_is_unit _ _) _ #align is_localization.to_inv_submonoid_mul IsLocalization.toInvSubmonoid_mul @[simp] theorem mul_toInvSubmonoid (m : M) : algebraMap R S m * (toInvSubmonoid M S m : S) = 1 := Submonoid.mul_leftInvEquiv_symm _ (submonoid_map_le_is_unit _ _) ⟨_, _⟩ #align is_localization.mul_to_inv_submonoid IsLocalization.mul_toInvSubmonoid @[simp] theorem smul_toInvSubmonoid (m : M) : m • (toInvSubmonoid M S m : S) = 1 := by convert mul_toInvSubmonoid M S m ext rw [← Algebra.smul_def] rfl #align is_localization.smul_to_inv_submonoid IsLocalization.smul_toInvSubmonoid variable {S} -- Porting note: `surj'` was taken, so use `surj''` instead theorem surj'' (z : S) : ∃ (r : R) (m : M), z = r • (toInvSubmonoid M S m : S) := by rcases IsLocalization.surj M z with ⟨⟨r, m⟩, e : z * _ = algebraMap R S r⟩ refine ⟨r, m, ?_⟩ rw [Algebra.smul_def, ← e, mul_assoc] simp #align is_localization.surj' IsLocalization.surj'' theorem toInvSubmonoid_eq_mk' (x : M) : (toInvSubmonoid M S x : S) = mk' S 1 x := by rw [← (IsLocalization.map_units S x).mul_left_inj] simp #align is_localization.to_inv_submonoid_eq_mk' IsLocalization.toInvSubmonoid_eq_mk'
Mathlib/RingTheory/Localization/InvSubmonoid.lean
99
103
theorem mem_invSubmonoid_iff_exists_mk' (x : S) : x ∈ invSubmonoid M S ↔ ∃ m : M, mk' S 1 m = x := by
simp_rw [← toInvSubmonoid_eq_mk'] exact ⟨fun h => ⟨_, congr_arg Subtype.val (toInvSubmonoid_surjective M S ⟨x, h⟩).choose_spec⟩, fun h => h.choose_spec ▸ (toInvSubmonoid M S h.choose).prop⟩
import Mathlib.RingTheory.Flat.Basic import Mathlib.LinearAlgebra.TensorProduct.Vanishing import Mathlib.Algebra.Module.FinitePresentation universe u variable {R M : Type u} [CommRing R] [AddCommGroup M] [Module R M] open Classical DirectSum LinearMap TensorProduct Finsupp open scoped BigOperators namespace Module variable {ι : Type u} [Fintype ι] (f : ι → R) (x : ι → M) abbrev IsTrivialRelation : Prop := ∃ (κ : Type u) (_ : Fintype κ) (a : ι → κ → R) (y : κ → M), (∀ i, x i = ∑ j, a i j • y j) ∧ ∀ j, ∑ i, f i * a i j = 0 variable {f x}
Mathlib/RingTheory/Flat/EquationalCriterion.lean
81
83
theorem isTrivialRelation_iff_vanishesTrivially : IsTrivialRelation f x ↔ VanishesTrivially R f x := by
simp only [IsTrivialRelation, VanishesTrivially, smul_eq_mul, mul_comm]
import Mathlib.Geometry.Manifold.ContMDiff.Defs open Set Filter Function open scoped Topology Manifold variable {𝕜 : Type*} [NontriviallyNormedField 𝕜] -- declare a smooth manifold `M` over the pair `(E, H)`. {E : Type*} [NormedAddCommGroup E] [NormedSpace 𝕜 E] {H : Type*} [TopologicalSpace H] (I : ModelWithCorners 𝕜 E H) {M : Type*} [TopologicalSpace M] [ChartedSpace H M] [SmoothManifoldWithCorners I M] -- declare a smooth manifold `M'` over the pair `(E', H')`. {E' : Type*} [NormedAddCommGroup E'] [NormedSpace 𝕜 E'] {H' : Type*} [TopologicalSpace H'] (I' : ModelWithCorners 𝕜 E' H') {M' : Type*} [TopologicalSpace M'] [ChartedSpace H' M'] [SmoothManifoldWithCorners I' M'] -- declare a manifold `M''` over the pair `(E'', H'')`. {E'' : Type*} [NormedAddCommGroup E''] [NormedSpace 𝕜 E''] {H'' : Type*} [TopologicalSpace H''] {I'' : ModelWithCorners 𝕜 E'' H''} {M'' : Type*} [TopologicalSpace M''] [ChartedSpace H'' M''] -- declare functions, sets, points and smoothness indices {e : PartialHomeomorph M H} {e' : PartialHomeomorph M' H'} {f f₁ : M → M'} {s s₁ t : Set M} {x : M} {m n : ℕ∞} variable {I I'} section id variable {c : M'}
Mathlib/Geometry/Manifold/ContMDiff/Basic.lean
244
248
theorem contMDiff_const : ContMDiff I I' n fun _ : M => c := by
intro x refine ⟨continuousWithinAt_const, ?_⟩ simp only [ContDiffWithinAtProp, (· ∘ ·)] exact contDiffWithinAt_const
import Mathlib.Analysis.SpecificLimits.Basic import Mathlib.RingTheory.Polynomial.Bernstein import Mathlib.Topology.ContinuousFunction.Polynomial import Mathlib.Topology.ContinuousFunction.Compact #align_import analysis.special_functions.bernstein from "leanprover-community/mathlib"@"2c1d8ca2812b64f88992a5294ea3dba144755cd1" set_option linter.uppercaseLean3 false -- S noncomputable section open scoped Classical BoundedContinuousFunction unitInterval def bernstein (n ν : ℕ) : C(I, ℝ) := (bernsteinPolynomial ℝ n ν).toContinuousMapOn I #align bernstein bernstein @[simp] theorem bernstein_apply (n ν : ℕ) (x : I) : bernstein n ν x = (n.choose ν : ℝ) * (x : ℝ) ^ ν * (1 - (x : ℝ)) ^ (n - ν) := by dsimp [bernstein, Polynomial.toContinuousMapOn, Polynomial.toContinuousMap, bernsteinPolynomial] simp #align bernstein_apply bernstein_apply theorem bernstein_nonneg {n ν : ℕ} {x : I} : 0 ≤ bernstein n ν x := by simp only [bernstein_apply] have h₁ : (0:ℝ) ≤ x := by unit_interval have h₂ : (0:ℝ) ≤ 1 - x := by unit_interval positivity #align bernstein_nonneg bernstein_nonneg namespace bernstein def z {n : ℕ} (k : Fin (n + 1)) : I := ⟨(k : ℝ) / n, by cases' n with n · norm_num · have h₁ : 0 < (n.succ : ℝ) := mod_cast Nat.succ_pos _ have h₂ : ↑k ≤ n.succ := mod_cast Fin.le_last k rw [Set.mem_Icc, le_div_iff h₁, div_le_iff h₁] norm_cast simp [h₂]⟩ #align bernstein.z bernstein.z local postfix:90 "/ₙ" => z theorem probability (n : ℕ) (x : I) : (∑ k : Fin (n + 1), bernstein n k x) = 1 := by have := bernsteinPolynomial.sum ℝ n apply_fun fun p => Polynomial.aeval (x : ℝ) p at this simp? [AlgHom.map_sum, Finset.sum_range] at this says simp only [Finset.sum_range, map_sum, Polynomial.coe_aeval_eq_eval, map_one] at this exact this #align bernstein.probability bernstein.probability
Mathlib/Analysis/SpecialFunctions/Bernstein.lean
117
136
theorem variance {n : ℕ} (h : 0 < (n : ℝ)) (x : I) : (∑ k : Fin (n + 1), (x - k/ₙ : ℝ) ^ 2 * bernstein n k x) = (x : ℝ) * (1 - x) / n := by
have h' : (n : ℝ) ≠ 0 := ne_of_gt h apply_fun fun x : ℝ => x * n using GroupWithZero.mul_right_injective h' apply_fun fun x : ℝ => x * n using GroupWithZero.mul_right_injective h' dsimp conv_lhs => simp only [Finset.sum_mul, z] conv_rhs => rw [div_mul_cancel₀ _ h'] have := bernsteinPolynomial.variance ℝ n apply_fun fun p => Polynomial.aeval (x : ℝ) p at this simp? [AlgHom.map_sum, Finset.sum_range, ← Polynomial.natCast_mul] at this says simp only [nsmul_eq_mul, Finset.sum_range, map_sum, map_mul, map_pow, map_sub, map_natCast, Polynomial.aeval_X, Polynomial.coe_aeval_eq_eval, map_one] at this convert this using 1 · congr 1; funext k rw [mul_comm _ (n : ℝ), mul_comm _ (n : ℝ), ← mul_assoc, ← mul_assoc] congr 1 field_simp [h] ring · ring
import Mathlib.Data.Fintype.Option import Mathlib.Data.Fintype.Prod import Mathlib.Data.Fintype.Pi import Mathlib.Data.Vector.Basic import Mathlib.Data.PFun import Mathlib.Logic.Function.Iterate import Mathlib.Order.Basic import Mathlib.Tactic.ApplyFun #align_import computability.turing_machine from "leanprover-community/mathlib"@"4c19a16e4b705bf135cf9a80ac18fcc99c438514" assert_not_exists MonoidWithZero open Relation open Nat (iterate) open Function (update iterate_succ iterate_succ_apply iterate_succ' iterate_succ_apply' iterate_zero_apply) namespace Turing def BlankExtends {Γ} [Inhabited Γ] (l₁ l₂ : List Γ) : Prop := ∃ n, l₂ = l₁ ++ List.replicate n default #align turing.blank_extends Turing.BlankExtends @[refl] theorem BlankExtends.refl {Γ} [Inhabited Γ] (l : List Γ) : BlankExtends l l := ⟨0, by simp⟩ #align turing.blank_extends.refl Turing.BlankExtends.refl @[trans]
Mathlib/Computability/TuringMachine.lean
85
88
theorem BlankExtends.trans {Γ} [Inhabited Γ] {l₁ l₂ l₃ : List Γ} : BlankExtends l₁ l₂ → BlankExtends l₂ l₃ → BlankExtends l₁ l₃ := by
rintro ⟨i, rfl⟩ ⟨j, rfl⟩ exact ⟨i + j, by simp [List.replicate_add]⟩
import Mathlib.GroupTheory.QuotientGroup import Mathlib.LinearAlgebra.Span #align_import linear_algebra.quotient from "leanprover-community/mathlib"@"48085f140e684306f9e7da907cd5932056d1aded" -- For most of this file we work over a noncommutative ring section Ring namespace Submodule variable {R M : Type*} {r : R} {x y : M} [Ring R] [AddCommGroup M] [Module R M] variable (p p' : Submodule R M) open LinearMap QuotientAddGroup def quotientRel : Setoid M := QuotientAddGroup.leftRel p.toAddSubgroup #align submodule.quotient_rel Submodule.quotientRel theorem quotientRel_r_def {x y : M} : @Setoid.r _ p.quotientRel x y ↔ x - y ∈ p := Iff.trans (by rw [leftRel_apply, sub_eq_add_neg, neg_add, neg_neg] rfl) neg_mem_iff #align submodule.quotient_rel_r_def Submodule.quotientRel_r_def instance hasQuotient : HasQuotient M (Submodule R M) := ⟨fun p => Quotient (quotientRel p)⟩ #align submodule.has_quotient Submodule.hasQuotient namespace Quotient def mk {p : Submodule R M} : M → M ⧸ p := Quotient.mk'' #align submodule.quotient.mk Submodule.Quotient.mk @[simp] theorem mk'_eq_mk' {p : Submodule R M} (x : M) : @Quotient.mk' _ (quotientRel p) x = (mk : M → M ⧸ p) x := rfl #align submodule.quotient.mk_eq_mk Submodule.Quotient.mk'_eq_mk' @[simp] theorem mk''_eq_mk {p : Submodule R M} (x : M) : (Quotient.mk'' x : M ⧸ p) = (mk : M → M ⧸ p) x := rfl #align submodule.quotient.mk'_eq_mk Submodule.Quotient.mk''_eq_mk @[simp] theorem quot_mk_eq_mk {p : Submodule R M} (x : M) : (Quot.mk _ x : M ⧸ p) = (mk : M → M ⧸ p) x := rfl #align submodule.quotient.quot_mk_eq_mk Submodule.Quotient.quot_mk_eq_mk protected theorem eq' {x y : M} : (mk x : M ⧸ p) = (mk : M → M ⧸ p) y ↔ -x + y ∈ p := QuotientAddGroup.eq #align submodule.quotient.eq' Submodule.Quotient.eq' protected theorem eq {x y : M} : (mk x : M ⧸ p) = (mk y : M ⧸ p) ↔ x - y ∈ p := (Submodule.Quotient.eq' p).trans (leftRel_apply.symm.trans p.quotientRel_r_def) #align submodule.quotient.eq Submodule.Quotient.eq instance : Zero (M ⧸ p) where -- Use Quotient.mk'' instead of mk here because mk is not reducible. -- This would lead to non-defeq diamonds. -- See also the same comment at the One instance for Con. zero := Quotient.mk'' 0 instance : Inhabited (M ⧸ p) := ⟨0⟩ @[simp] theorem mk_zero : mk 0 = (0 : M ⧸ p) := rfl #align submodule.quotient.mk_zero Submodule.Quotient.mk_zero @[simp]
Mathlib/LinearAlgebra/Quotient.lean
100
100
theorem mk_eq_zero : (mk x : M ⧸ p) = 0 ↔ x ∈ p := by
simpa using (Quotient.eq' p : mk x = 0 ↔ _)
import Mathlib.Algebra.ContinuedFractions.Basic import Mathlib.Algebra.GroupWithZero.Basic #align_import algebra.continued_fractions.translations from "leanprover-community/mathlib"@"a7e36e48519ab281320c4d192da6a7b348ce40ad" namespace GeneralizedContinuedFraction section General variable {α : Type*} {g : GeneralizedContinuedFraction α} {n : ℕ} theorem terminatedAt_iff_s_terminatedAt : g.TerminatedAt n ↔ g.s.TerminatedAt n := by rfl #align generalized_continued_fraction.terminated_at_iff_s_terminated_at GeneralizedContinuedFraction.terminatedAt_iff_s_terminatedAt theorem terminatedAt_iff_s_none : g.TerminatedAt n ↔ g.s.get? n = none := by rfl #align generalized_continued_fraction.terminated_at_iff_s_none GeneralizedContinuedFraction.terminatedAt_iff_s_none theorem part_num_none_iff_s_none : g.partialNumerators.get? n = none ↔ g.s.get? n = none := by cases s_nth_eq : g.s.get? n <;> simp [partialNumerators, s_nth_eq] #align generalized_continued_fraction.part_num_none_iff_s_none GeneralizedContinuedFraction.part_num_none_iff_s_none theorem terminatedAt_iff_part_num_none : g.TerminatedAt n ↔ g.partialNumerators.get? n = none := by rw [terminatedAt_iff_s_none, part_num_none_iff_s_none] #align generalized_continued_fraction.terminated_at_iff_part_num_none GeneralizedContinuedFraction.terminatedAt_iff_part_num_none theorem part_denom_none_iff_s_none : g.partialDenominators.get? n = none ↔ g.s.get? n = none := by cases s_nth_eq : g.s.get? n <;> simp [partialDenominators, s_nth_eq] #align generalized_continued_fraction.part_denom_none_iff_s_none GeneralizedContinuedFraction.part_denom_none_iff_s_none theorem terminatedAt_iff_part_denom_none : g.TerminatedAt n ↔ g.partialDenominators.get? n = none := by rw [terminatedAt_iff_s_none, part_denom_none_iff_s_none] #align generalized_continued_fraction.terminated_at_iff_part_denom_none GeneralizedContinuedFraction.terminatedAt_iff_part_denom_none theorem part_num_eq_s_a {gp : Pair α} (s_nth_eq : g.s.get? n = some gp) : g.partialNumerators.get? n = some gp.a := by simp [partialNumerators, s_nth_eq] #align generalized_continued_fraction.part_num_eq_s_a GeneralizedContinuedFraction.part_num_eq_s_a theorem part_denom_eq_s_b {gp : Pair α} (s_nth_eq : g.s.get? n = some gp) : g.partialDenominators.get? n = some gp.b := by simp [partialDenominators, s_nth_eq] #align generalized_continued_fraction.part_denom_eq_s_b GeneralizedContinuedFraction.part_denom_eq_s_b
Mathlib/Algebra/ContinuedFractions/Translations.lean
66
68
theorem exists_s_a_of_part_num {a : α} (nth_part_num_eq : g.partialNumerators.get? n = some a) : ∃ gp, g.s.get? n = some gp ∧ gp.a = a := by
simpa [partialNumerators, Stream'.Seq.map_get?] using nth_part_num_eq
import Mathlib.Order.Filter.EventuallyConst import Mathlib.Order.PartialSups import Mathlib.Algebra.Module.Submodule.IterateMapComap import Mathlib.RingTheory.OrzechProperty import Mathlib.RingTheory.Nilpotent.Lemmas #align_import ring_theory.noetherian from "leanprover-community/mathlib"@"210657c4ea4a4a7b234392f70a3a2a83346dfa90" open Set Filter Pointwise -- Porting note: should this be renamed to `Noetherian`? class IsNoetherian (R M) [Semiring R] [AddCommMonoid M] [Module R M] : Prop where noetherian : ∀ s : Submodule R M, s.FG #align is_noetherian IsNoetherian attribute [inherit_doc IsNoetherian] IsNoetherian.noetherian section variable {R : Type*} {M : Type*} {P : Type*} variable [Semiring R] [AddCommMonoid M] [AddCommMonoid P] variable [Module R M] [Module R P] open IsNoetherian theorem isNoetherian_def : IsNoetherian R M ↔ ∀ s : Submodule R M, s.FG := ⟨fun h => h.noetherian, IsNoetherian.mk⟩ #align is_noetherian_def isNoetherian_def theorem isNoetherian_submodule {N : Submodule R M} : IsNoetherian R N ↔ ∀ s : Submodule R M, s ≤ N → s.FG := by refine ⟨fun ⟨hn⟩ => fun s hs => have : s ≤ LinearMap.range N.subtype := N.range_subtype.symm ▸ hs Submodule.map_comap_eq_self this ▸ (hn _).map _, fun h => ⟨fun s => ?_⟩⟩ have f := (Submodule.equivMapOfInjective N.subtype Subtype.val_injective s).symm have h₁ := h (s.map N.subtype) (Submodule.map_subtype_le N s) have h₂ : (⊤ : Submodule R (s.map N.subtype)).map f = ⊤ := by simp have h₃ := ((Submodule.fg_top _).2 h₁).map (↑f : _ →ₗ[R] s) exact (Submodule.fg_top _).1 (h₂ ▸ h₃) #align is_noetherian_submodule isNoetherian_submodule theorem isNoetherian_submodule_left {N : Submodule R M} : IsNoetherian R N ↔ ∀ s : Submodule R M, (N ⊓ s).FG := isNoetherian_submodule.trans ⟨fun H _ => H _ inf_le_left, fun H _ hs => inf_of_le_right hs ▸ H _⟩ #align is_noetherian_submodule_left isNoetherian_submodule_left theorem isNoetherian_submodule_right {N : Submodule R M} : IsNoetherian R N ↔ ∀ s : Submodule R M, (s ⊓ N).FG := isNoetherian_submodule.trans ⟨fun H _ => H _ inf_le_right, fun H _ hs => inf_of_le_left hs ▸ H _⟩ #align is_noetherian_submodule_right isNoetherian_submodule_right instance isNoetherian_submodule' [IsNoetherian R M] (N : Submodule R M) : IsNoetherian R N := isNoetherian_submodule.2 fun _ _ => IsNoetherian.noetherian _ #align is_noetherian_submodule' isNoetherian_submodule' theorem isNoetherian_of_le {s t : Submodule R M} [ht : IsNoetherian R t] (h : s ≤ t) : IsNoetherian R s := isNoetherian_submodule.mpr fun _ hs' => isNoetherian_submodule.mp ht _ (le_trans hs' h) #align is_noetherian_of_le isNoetherian_of_le variable (M) theorem isNoetherian_of_surjective (f : M →ₗ[R] P) (hf : LinearMap.range f = ⊤) [IsNoetherian R M] : IsNoetherian R P := ⟨fun s => have : (s.comap f).map f = s := Submodule.map_comap_eq_self <| hf.symm ▸ le_top this ▸ (noetherian _).map _⟩ #align is_noetherian_of_surjective isNoetherian_of_surjective variable {M} instance isNoetherian_quotient {R} [Ring R] {M} [AddCommGroup M] [Module R M] (N : Submodule R M) [IsNoetherian R M] : IsNoetherian R (M ⧸ N) := isNoetherian_of_surjective _ _ (LinearMap.range_eq_top.mpr N.mkQ_surjective) #align submodule.quotient.is_noetherian isNoetherian_quotient @[deprecated (since := "2024-04-27"), nolint defLemma] alias Submodule.Quotient.isNoetherian := isNoetherian_quotient theorem isNoetherian_of_linearEquiv (f : M ≃ₗ[R] P) [IsNoetherian R M] : IsNoetherian R P := isNoetherian_of_surjective _ f.toLinearMap f.range #align is_noetherian_of_linear_equiv isNoetherian_of_linearEquiv
Mathlib/RingTheory/Noetherian.lean
136
139
theorem isNoetherian_top_iff : IsNoetherian R (⊤ : Submodule R M) ↔ IsNoetherian R M := by
constructor <;> intro h · exact isNoetherian_of_linearEquiv (LinearEquiv.ofTop (⊤ : Submodule R M) rfl) · exact isNoetherian_of_linearEquiv (LinearEquiv.ofTop (⊤ : Submodule R M) rfl).symm
import Mathlib.Analysis.Calculus.ContDiff.Basic import Mathlib.Analysis.Calculus.Deriv.Linear import Mathlib.Analysis.Complex.Conformal import Mathlib.Analysis.Calculus.Conformal.NormedSpace #align_import analysis.complex.real_deriv from "leanprover-community/mathlib"@"3bce8d800a6f2b8f63fe1e588fd76a9ff4adcebe" section RealDerivOfComplex open Complex variable {e : ℂ → ℂ} {e' : ℂ} {z : ℝ} theorem HasStrictDerivAt.real_of_complex (h : HasStrictDerivAt e e' z) : HasStrictDerivAt (fun x : ℝ => (e x).re) e'.re z := by have A : HasStrictFDerivAt ((↑) : ℝ → ℂ) ofRealCLM z := ofRealCLM.hasStrictFDerivAt have B : HasStrictFDerivAt e ((ContinuousLinearMap.smulRight 1 e' : ℂ →L[ℂ] ℂ).restrictScalars ℝ) (ofRealCLM z) := h.hasStrictFDerivAt.restrictScalars ℝ have C : HasStrictFDerivAt re reCLM (e (ofRealCLM z)) := reCLM.hasStrictFDerivAt -- Porting note: this should be by: -- simpa using (C.comp z (B.comp z A)).hasStrictDerivAt -- but for some reason simp can not use `ContinuousLinearMap.comp_apply` convert (C.comp z (B.comp z A)).hasStrictDerivAt rw [ContinuousLinearMap.comp_apply, ContinuousLinearMap.comp_apply] simp #align has_strict_deriv_at.real_of_complex HasStrictDerivAt.real_of_complex theorem HasDerivAt.real_of_complex (h : HasDerivAt e e' z) : HasDerivAt (fun x : ℝ => (e x).re) e'.re z := by have A : HasFDerivAt ((↑) : ℝ → ℂ) ofRealCLM z := ofRealCLM.hasFDerivAt have B : HasFDerivAt e ((ContinuousLinearMap.smulRight 1 e' : ℂ →L[ℂ] ℂ).restrictScalars ℝ) (ofRealCLM z) := h.hasFDerivAt.restrictScalars ℝ have C : HasFDerivAt re reCLM (e (ofRealCLM z)) := reCLM.hasFDerivAt -- Porting note: this should be by: -- simpa using (C.comp z (B.comp z A)).hasStrictDerivAt -- but for some reason simp can not use `ContinuousLinearMap.comp_apply` convert (C.comp z (B.comp z A)).hasDerivAt rw [ContinuousLinearMap.comp_apply, ContinuousLinearMap.comp_apply] simp #align has_deriv_at.real_of_complex HasDerivAt.real_of_complex theorem ContDiffAt.real_of_complex {n : ℕ∞} (h : ContDiffAt ℂ n e z) : ContDiffAt ℝ n (fun x : ℝ => (e x).re) z := by have A : ContDiffAt ℝ n ((↑) : ℝ → ℂ) z := ofRealCLM.contDiff.contDiffAt have B : ContDiffAt ℝ n e z := h.restrict_scalars ℝ have C : ContDiffAt ℝ n re (e z) := reCLM.contDiff.contDiffAt exact C.comp z (B.comp z A) #align cont_diff_at.real_of_complex ContDiffAt.real_of_complex theorem ContDiff.real_of_complex {n : ℕ∞} (h : ContDiff ℂ n e) : ContDiff ℝ n fun x : ℝ => (e x).re := contDiff_iff_contDiffAt.2 fun _ => h.contDiffAt.real_of_complex #align cont_diff.real_of_complex ContDiff.real_of_complex variable {E : Type*} [NormedAddCommGroup E] [NormedSpace ℂ E]
Mathlib/Analysis/Complex/RealDeriv.lean
99
103
theorem HasStrictDerivAt.complexToReal_fderiv' {f : ℂ → E} {x : ℂ} {f' : E} (h : HasStrictDerivAt f f' x) : HasStrictFDerivAt f (reCLM.smulRight f' + I • imCLM.smulRight f') x := by
simpa only [Complex.restrictScalars_one_smulRight'] using h.hasStrictFDerivAt.restrictScalars ℝ
import Mathlib.MeasureTheory.MeasurableSpace.Basic import Mathlib.MeasureTheory.Measure.MeasureSpaceDef #align_import measure_theory.function.ae_measurable_sequence from "leanprover-community/mathlib"@"d003c55042c3cd08aefd1ae9a42ef89441cdaaf3" open MeasureTheory open scoped Classical variable {ι : Sort*} {α β γ : Type*} [MeasurableSpace α] [MeasurableSpace β] {f : ι → α → β} {μ : Measure α} {p : α → (ι → β) → Prop} def aeSeqSet (hf : ∀ i, AEMeasurable (f i) μ) (p : α → (ι → β) → Prop) : Set α := (toMeasurable μ { x | (∀ i, f i x = (hf i).mk (f i) x) ∧ p x fun n => f n x }ᶜ)ᶜ #align ae_seq_set aeSeqSet noncomputable def aeSeq (hf : ∀ i, AEMeasurable (f i) μ) (p : α → (ι → β) → Prop) : ι → α → β := fun i x => ite (x ∈ aeSeqSet hf p) ((hf i).mk (f i) x) (⟨f i x⟩ : Nonempty β).some #align ae_seq aeSeq namespace aeSeq theorem aeSeqSet_measurableSet {hf : ∀ i, AEMeasurable (f i) μ} : MeasurableSet (aeSeqSet hf p) := (measurableSet_toMeasurable _ _).compl #align ae_seq.ae_seq_set_measurable_set aeSeq.aeSeqSet_measurableSet theorem measurable (hf : ∀ i, AEMeasurable (f i) μ) (p : α → (ι → β) → Prop) (i : ι) : Measurable (aeSeq hf p i) := Measurable.ite aeSeqSet_measurableSet (hf i).measurable_mk <| measurable_const' fun _ _ => rfl #align ae_seq.measurable aeSeq.measurable
Mathlib/MeasureTheory/Function/AEMeasurableSequence.lean
100
105
theorem measure_compl_aeSeqSet_eq_zero [Countable ι] (hf : ∀ i, AEMeasurable (f i) μ) (hp : ∀ᵐ x ∂μ, p x fun n => f n x) : μ (aeSeqSet hf p)ᶜ = 0 := by
rw [aeSeqSet, compl_compl, measure_toMeasurable] have hf_eq := fun i => (hf i).ae_eq_mk simp_rw [Filter.EventuallyEq, ← ae_all_iff] at hf_eq exact Filter.Eventually.and hf_eq hp
import Mathlib.GroupTheory.Solvable import Mathlib.FieldTheory.PolynomialGaloisGroup import Mathlib.RingTheory.RootsOfUnity.Basic #align_import field_theory.abel_ruffini from "leanprover-community/mathlib"@"e3f4be1fcb5376c4948d7f095bec45350bfb9d1a" noncomputable section open scoped Classical Polynomial IntermediateField open Polynomial IntermediateField section AbelRuffini variable {F : Type*} [Field F] {E : Type*} [Field E] [Algebra F E] theorem gal_zero_isSolvable : IsSolvable (0 : F[X]).Gal := by infer_instance #align gal_zero_is_solvable gal_zero_isSolvable theorem gal_one_isSolvable : IsSolvable (1 : F[X]).Gal := by infer_instance #align gal_one_is_solvable gal_one_isSolvable theorem gal_C_isSolvable (x : F) : IsSolvable (C x).Gal := by infer_instance set_option linter.uppercaseLean3 false in #align gal_C_is_solvable gal_C_isSolvable theorem gal_X_isSolvable : IsSolvable (X : F[X]).Gal := by infer_instance set_option linter.uppercaseLean3 false in #align gal_X_is_solvable gal_X_isSolvable theorem gal_X_sub_C_isSolvable (x : F) : IsSolvable (X - C x).Gal := by infer_instance set_option linter.uppercaseLean3 false in #align gal_X_sub_C_is_solvable gal_X_sub_C_isSolvable theorem gal_X_pow_isSolvable (n : ℕ) : IsSolvable (X ^ n : F[X]).Gal := by infer_instance set_option linter.uppercaseLean3 false in #align gal_X_pow_is_solvable gal_X_pow_isSolvable theorem gal_mul_isSolvable {p q : F[X]} (_ : IsSolvable p.Gal) (_ : IsSolvable q.Gal) : IsSolvable (p * q).Gal := solvable_of_solvable_injective (Gal.restrictProd_injective p q) #align gal_mul_is_solvable gal_mul_isSolvable theorem gal_prod_isSolvable {s : Multiset F[X]} (hs : ∀ p ∈ s, IsSolvable (Gal p)) : IsSolvable s.prod.Gal := by apply Multiset.induction_on' s · exact gal_one_isSolvable · intro p t hps _ ht rw [Multiset.insert_eq_cons, Multiset.prod_cons] exact gal_mul_isSolvable (hs p hps) ht #align gal_prod_is_solvable gal_prod_isSolvable theorem gal_isSolvable_of_splits {p q : F[X]} (_ : Fact (p.Splits (algebraMap F q.SplittingField))) (hq : IsSolvable q.Gal) : IsSolvable p.Gal := haveI : IsSolvable (q.SplittingField ≃ₐ[F] q.SplittingField) := hq solvable_of_surjective (AlgEquiv.restrictNormalHom_surjective q.SplittingField) #align gal_is_solvable_of_splits gal_isSolvable_of_splits theorem gal_isSolvable_tower (p q : F[X]) (hpq : p.Splits (algebraMap F q.SplittingField)) (hp : IsSolvable p.Gal) (hq : IsSolvable (q.map (algebraMap F p.SplittingField)).Gal) : IsSolvable q.Gal := by let K := p.SplittingField let L := q.SplittingField haveI : Fact (p.Splits (algebraMap F L)) := ⟨hpq⟩ let ϕ : (L ≃ₐ[K] L) ≃* (q.map (algebraMap F K)).Gal := (IsSplittingField.algEquiv L (q.map (algebraMap F K))).autCongr have ϕ_inj : Function.Injective ϕ.toMonoidHom := ϕ.injective haveI : IsSolvable (K ≃ₐ[F] K) := hp haveI : IsSolvable (L ≃ₐ[K] L) := solvable_of_solvable_injective ϕ_inj exact isSolvable_of_isScalarTower F p.SplittingField q.SplittingField #align gal_is_solvable_tower gal_isSolvable_tower section GalXPowSubC theorem gal_X_pow_sub_one_isSolvable (n : ℕ) : IsSolvable (X ^ n - 1 : F[X]).Gal := by by_cases hn : n = 0 · rw [hn, pow_zero, sub_self] exact gal_zero_isSolvable have hn' : 0 < n := pos_iff_ne_zero.mpr hn have hn'' : (X ^ n - 1 : F[X]) ≠ 0 := X_pow_sub_C_ne_zero hn' 1 apply isSolvable_of_comm intro σ τ ext a ha simp only [mem_rootSet_of_ne hn'', map_sub, aeval_X_pow, aeval_one, sub_eq_zero] at ha have key : ∀ σ : (X ^ n - 1 : F[X]).Gal, ∃ m : ℕ, σ a = a ^ m := by intro σ lift n to ℕ+ using hn' exact map_rootsOfUnity_eq_pow_self σ.toAlgHom (rootsOfUnity.mkOfPowEq a ha) obtain ⟨c, hc⟩ := key σ obtain ⟨d, hd⟩ := key τ rw [σ.mul_apply, τ.mul_apply, hc, τ.map_pow, hd, σ.map_pow, hc, ← pow_mul, pow_mul'] set_option linter.uppercaseLean3 false in #align gal_X_pow_sub_one_is_solvable gal_X_pow_sub_one_isSolvable
Mathlib/FieldTheory/AbelRuffini.lean
118
153
theorem gal_X_pow_sub_C_isSolvable_aux (n : ℕ) (a : F) (h : (X ^ n - 1 : F[X]).Splits (RingHom.id F)) : IsSolvable (X ^ n - C a).Gal := by
by_cases ha : a = 0 · rw [ha, C_0, sub_zero] exact gal_X_pow_isSolvable n have ha' : algebraMap F (X ^ n - C a).SplittingField a ≠ 0 := mt ((injective_iff_map_eq_zero _).mp (RingHom.injective _) a) ha by_cases hn : n = 0 · rw [hn, pow_zero, ← C_1, ← C_sub] exact gal_C_isSolvable (1 - a) have hn' : 0 < n := pos_iff_ne_zero.mpr hn have hn'' : X ^ n - C a ≠ 0 := X_pow_sub_C_ne_zero hn' a have hn''' : (X ^ n - 1 : F[X]) ≠ 0 := X_pow_sub_C_ne_zero hn' 1 have mem_range : ∀ {c : (X ^ n - C a).SplittingField}, (c ^ n = 1 → (∃ d, algebraMap F (X ^ n - C a).SplittingField d = c)) := fun {c} hc => RingHom.mem_range.mp (minpoly.mem_range_of_degree_eq_one F c (h.def.resolve_left hn''' (minpoly.irreducible ((SplittingField.instNormal (X ^ n - C a)).isIntegral c)) (minpoly.dvd F c (by rwa [map_id, AlgHom.map_sub, sub_eq_zero, aeval_X_pow, aeval_one])))) apply isSolvable_of_comm intro σ τ ext b hb rw [mem_rootSet_of_ne hn'', map_sub, aeval_X_pow, aeval_C, sub_eq_zero] at hb have hb' : b ≠ 0 := by intro hb' rw [hb', zero_pow hn] at hb exact ha' hb.symm have key : ∀ σ : (X ^ n - C a).Gal, ∃ c, σ b = b * algebraMap F _ c := by intro σ have key : (σ b / b) ^ n = 1 := by rw [div_pow, ← σ.map_pow, hb, σ.commutes, div_self ha'] obtain ⟨c, hc⟩ := mem_range key use c rw [hc, mul_div_cancel₀ (σ b) hb'] obtain ⟨c, hc⟩ := key σ obtain ⟨d, hd⟩ := key τ rw [σ.mul_apply, τ.mul_apply, hc, τ.map_mul, τ.commutes, hd, σ.map_mul, σ.commutes, hc, mul_assoc, mul_assoc, mul_right_inj' hb', mul_comm]
import Mathlib.LinearAlgebra.Basis.VectorSpace import Mathlib.LinearAlgebra.Dimension.Finite import Mathlib.SetTheory.Cardinal.Subfield import Mathlib.LinearAlgebra.Dimension.RankNullity #align_import linear_algebra.dimension from "leanprover-community/mathlib"@"47a5f8186becdbc826190ced4312f8199f9db6a5" noncomputable section universe u₀ u v v' v'' u₁' w w' variable {K R : Type u} {V V₁ V₂ V₃ : Type v} {V' V'₁ : Type v'} {V'' : Type v''} variable {ι : Type w} {ι' : Type w'} {η : Type u₁'} {φ : η → Type*} open Cardinal Basis Submodule Function Set section Module section Cardinal variable (K) variable [DivisionRing K] theorem max_aleph0_card_le_rank_fun_nat : max ℵ₀ #K ≤ Module.rank K (ℕ → K) := by have aleph0_le : ℵ₀ ≤ Module.rank K (ℕ → K) := (rank_finsupp_self K ℕ).symm.trans_le (Finsupp.lcoeFun.rank_le_of_injective <| by exact DFunLike.coe_injective) refine max_le aleph0_le ?_ obtain card_K | card_K := le_or_lt #K ℵ₀ · exact card_K.trans aleph0_le by_contra! obtain ⟨⟨ιK, bK⟩⟩ := Module.Free.exists_basis (R := K) (M := ℕ → K) let L := Subfield.closure (Set.range (fun i : ιK × ℕ ↦ bK i.1 i.2)) have hLK : #L < #K := by refine (Subfield.cardinal_mk_closure_le_max _).trans_lt (max_lt_iff.mpr ⟨mk_range_le.trans_lt ?_, card_K⟩) rwa [mk_prod, ← aleph0, lift_uzero, bK.mk_eq_rank'', mul_aleph0_eq aleph0_le] letI := Module.compHom K (RingHom.op L.subtype) obtain ⟨⟨ιL, bL⟩⟩ := Module.Free.exists_basis (R := Lᵐᵒᵖ) (M := K) have card_ιL : ℵ₀ ≤ #ιL := by contrapose! hLK haveI := @Fintype.ofFinite _ (lt_aleph0_iff_finite.mp hLK) rw [bL.repr.toEquiv.cardinal_eq, mk_finsupp_of_fintype, ← MulOpposite.opEquiv.cardinal_eq] at card_K ⊢ apply power_nat_le contrapose! card_K exact (power_lt_aleph0 card_K <| nat_lt_aleph0 _).le obtain ⟨e⟩ := lift_mk_le'.mp (card_ιL.trans_eq (lift_uzero #ιL).symm) have rep_e := bK.total_repr (bL ∘ e) rw [Finsupp.total_apply, Finsupp.sum] at rep_e set c := bK.repr (bL ∘ e) set s := c.support let f i (j : s) : L := ⟨bK j i, Subfield.subset_closure ⟨(j, i), rfl⟩⟩ have : ¬LinearIndependent Lᵐᵒᵖ f := fun h ↦ by have := h.cardinal_lift_le_rank rw [lift_uzero, (LinearEquiv.piCongrRight fun _ ↦ MulOpposite.opLinearEquiv Lᵐᵒᵖ).rank_eq, rank_fun'] at this exact (nat_lt_aleph0 _).not_le this obtain ⟨t, g, eq0, i, hi, hgi⟩ := not_linearIndependent_iff.mp this refine hgi (linearIndependent_iff'.mp (bL.linearIndependent.comp e e.injective) t g ?_ i hi) clear_value c s simp_rw [← rep_e, Finset.sum_apply, Pi.smul_apply, Finset.smul_sum] rw [Finset.sum_comm] refine Finset.sum_eq_zero fun i hi ↦ ?_ replace eq0 := congr_arg L.subtype (congr_fun eq0 ⟨i, hi⟩) rw [Finset.sum_apply, map_sum] at eq0 have : SMulCommClass Lᵐᵒᵖ K K := ⟨fun _ _ _ ↦ mul_assoc _ _ _⟩ simp_rw [smul_comm _ (c i), ← Finset.smul_sum] erw [eq0, smul_zero] variable {K} open Function in
Mathlib/LinearAlgebra/Dimension/DivisionRing.lean
288
300
theorem rank_fun_infinite {ι : Type v} [hι : Infinite ι] : Module.rank K (ι → K) = #(ι → K) := by
obtain ⟨⟨ιK, bK⟩⟩ := Module.Free.exists_basis (R := K) (M := ι → K) obtain ⟨e⟩ := lift_mk_le'.mp ((aleph0_le_mk_iff.mpr hι).trans_eq (lift_uzero #ι).symm) have := LinearMap.lift_rank_le_of_injective _ <| LinearMap.funLeft_injective_of_surjective K K _ (invFun_surjective e.injective) rw [lift_umax.{u,v}, lift_id'.{u,v}] at this have key := (lift_le.{v}.mpr <| max_aleph0_card_le_rank_fun_nat K).trans this rw [lift_max, lift_aleph0, max_le_iff] at key haveI : Infinite ιK := by rw [← aleph0_le_mk_iff, bK.mk_eq_rank'']; exact key.1 rw [bK.repr.toEquiv.cardinal_eq, mk_finsupp_lift_of_infinite, lift_umax.{u,v}, lift_id'.{u,v}, bK.mk_eq_rank'', eq_comm, max_eq_left] exact key.2
import Mathlib.MeasureTheory.MeasurableSpace.Defs import Mathlib.SetTheory.Cardinal.Cofinality import Mathlib.SetTheory.Cardinal.Continuum #align_import measure_theory.card_measurable_space from "leanprover-community/mathlib"@"f2b108e8e97ba393f22bf794989984ddcc1da89b" universe u variable {α : Type u} open Cardinal Set -- Porting note: fix universe below, not here local notation "ω₁" => (WellOrder.α <| Quotient.out <| Cardinal.ord (aleph 1 : Cardinal)) namespace MeasurableSpace def generateMeasurableRec (s : Set (Set α)) : (ω₁ : Type u) → Set (Set α) | i => let S := ⋃ j : Iio i, generateMeasurableRec s (j.1) s ∪ {∅} ∪ compl '' S ∪ Set.range fun f : ℕ → S => ⋃ n, (f n).1 termination_by i => i decreasing_by exact j.2 #align measurable_space.generate_measurable_rec MeasurableSpace.generateMeasurableRec theorem self_subset_generateMeasurableRec (s : Set (Set α)) (i : ω₁) : s ⊆ generateMeasurableRec s i := by unfold generateMeasurableRec apply_rules [subset_union_of_subset_left] exact subset_rfl #align measurable_space.self_subset_generate_measurable_rec MeasurableSpace.self_subset_generateMeasurableRec theorem empty_mem_generateMeasurableRec (s : Set (Set α)) (i : ω₁) : ∅ ∈ generateMeasurableRec s i := by unfold generateMeasurableRec exact mem_union_left _ (mem_union_left _ (mem_union_right _ (mem_singleton ∅))) #align measurable_space.empty_mem_generate_measurable_rec MeasurableSpace.empty_mem_generateMeasurableRec theorem compl_mem_generateMeasurableRec {s : Set (Set α)} {i j : ω₁} (h : j < i) {t : Set α} (ht : t ∈ generateMeasurableRec s j) : tᶜ ∈ generateMeasurableRec s i := by unfold generateMeasurableRec exact mem_union_left _ (mem_union_right _ ⟨t, mem_iUnion.2 ⟨⟨j, h⟩, ht⟩, rfl⟩) #align measurable_space.compl_mem_generate_measurable_rec MeasurableSpace.compl_mem_generateMeasurableRec
Mathlib/MeasureTheory/MeasurableSpace/Card.lean
74
78
theorem iUnion_mem_generateMeasurableRec {s : Set (Set α)} {i : ω₁} {f : ℕ → Set α} (hf : ∀ n, ∃ j < i, f n ∈ generateMeasurableRec s j) : (⋃ n, f n) ∈ generateMeasurableRec s i := by
unfold generateMeasurableRec exact mem_union_right _ ⟨fun n => ⟨f n, let ⟨j, hj, hf⟩ := hf n; mem_iUnion.2 ⟨⟨j, hj⟩, hf⟩⟩, rfl⟩
import Mathlib.Analysis.Calculus.TangentCone import Mathlib.Analysis.NormedSpace.OperatorNorm.Asymptotics #align_import analysis.calculus.fderiv.basic from "leanprover-community/mathlib"@"41bef4ae1254365bc190aee63b947674d2977f01" open Filter Asymptotics ContinuousLinearMap Set Metric open scoped Classical open Topology NNReal Filter Asymptotics ENNReal noncomputable section section variable {𝕜 : Type*} [NontriviallyNormedField 𝕜] variable {E : Type*} [NormedAddCommGroup E] [NormedSpace 𝕜 E] variable {F : Type*} [NormedAddCommGroup F] [NormedSpace 𝕜 F] variable {G : Type*} [NormedAddCommGroup G] [NormedSpace 𝕜 G] variable {G' : Type*} [NormedAddCommGroup G'] [NormedSpace 𝕜 G'] @[mk_iff hasFDerivAtFilter_iff_isLittleO] structure HasFDerivAtFilter (f : E → F) (f' : E →L[𝕜] F) (x : E) (L : Filter E) : Prop where of_isLittleO :: isLittleO : (fun x' => f x' - f x - f' (x' - x)) =o[L] fun x' => x' - x #align has_fderiv_at_filter HasFDerivAtFilter @[fun_prop] def HasFDerivWithinAt (f : E → F) (f' : E →L[𝕜] F) (s : Set E) (x : E) := HasFDerivAtFilter f f' x (𝓝[s] x) #align has_fderiv_within_at HasFDerivWithinAt @[fun_prop] def HasFDerivAt (f : E → F) (f' : E →L[𝕜] F) (x : E) := HasFDerivAtFilter f f' x (𝓝 x) #align has_fderiv_at HasFDerivAt @[fun_prop] def HasStrictFDerivAt (f : E → F) (f' : E →L[𝕜] F) (x : E) := (fun p : E × E => f p.1 - f p.2 - f' (p.1 - p.2)) =o[𝓝 (x, x)] fun p : E × E => p.1 - p.2 #align has_strict_fderiv_at HasStrictFDerivAt variable (𝕜) @[fun_prop] def DifferentiableWithinAt (f : E → F) (s : Set E) (x : E) := ∃ f' : E →L[𝕜] F, HasFDerivWithinAt f f' s x #align differentiable_within_at DifferentiableWithinAt @[fun_prop] def DifferentiableAt (f : E → F) (x : E) := ∃ f' : E →L[𝕜] F, HasFDerivAt f f' x #align differentiable_at DifferentiableAt irreducible_def fderivWithin (f : E → F) (s : Set E) (x : E) : E →L[𝕜] F := if 𝓝[s \ {x}] x = ⊥ then 0 else if h : ∃ f', HasFDerivWithinAt f f' s x then Classical.choose h else 0 #align fderiv_within fderivWithin irreducible_def fderiv (f : E → F) (x : E) : E →L[𝕜] F := if h : ∃ f', HasFDerivAt f f' x then Classical.choose h else 0 #align fderiv fderiv @[fun_prop] def DifferentiableOn (f : E → F) (s : Set E) := ∀ x ∈ s, DifferentiableWithinAt 𝕜 f s x #align differentiable_on DifferentiableOn @[fun_prop] def Differentiable (f : E → F) := ∀ x, DifferentiableAt 𝕜 f x #align differentiable Differentiable variable {𝕜} variable {f f₀ f₁ g : E → F} variable {f' f₀' f₁' g' : E →L[𝕜] F} variable (e : E →L[𝕜] F) variable {x : E} variable {s t : Set E} variable {L L₁ L₂ : Filter E} theorem fderivWithin_zero_of_isolated (h : 𝓝[s \ {x}] x = ⊥) : fderivWithin 𝕜 f s x = 0 := by rw [fderivWithin, if_pos h] theorem fderivWithin_zero_of_nmem_closure (h : x ∉ closure s) : fderivWithin 𝕜 f s x = 0 := by apply fderivWithin_zero_of_isolated simp only [mem_closure_iff_nhdsWithin_neBot, neBot_iff, Ne, Classical.not_not] at h rw [eq_bot_iff, ← h] exact nhdsWithin_mono _ diff_subset theorem fderivWithin_zero_of_not_differentiableWithinAt (h : ¬DifferentiableWithinAt 𝕜 f s x) : fderivWithin 𝕜 f s x = 0 := by have : ¬∃ f', HasFDerivWithinAt f f' s x := h simp [fderivWithin, this] #align fderiv_within_zero_of_not_differentiable_within_at fderivWithin_zero_of_not_differentiableWithinAt
Mathlib/Analysis/Calculus/FDeriv/Basic.lean
231
233
theorem fderiv_zero_of_not_differentiableAt (h : ¬DifferentiableAt 𝕜 f x) : fderiv 𝕜 f x = 0 := by
have : ¬∃ f', HasFDerivAt f f' x := h simp [fderiv, this]
import Mathlib.Analysis.InnerProductSpace.Basic import Mathlib.Analysis.NormedSpace.Dual import Mathlib.MeasureTheory.Function.StronglyMeasurable.Lp import Mathlib.MeasureTheory.Integral.SetIntegral #align_import measure_theory.function.ae_eq_of_integral from "leanprover-community/mathlib"@"915591b2bb3ea303648db07284a161a7f2a9e3d4" open MeasureTheory TopologicalSpace NormedSpace Filter open scoped ENNReal NNReal MeasureTheory Topology namespace MeasureTheory variable {α E : Type*} {m m0 : MeasurableSpace α} {μ : Measure α} {s t : Set α} [NormedAddCommGroup E] [NormedSpace ℝ E] [CompleteSpace E] {p : ℝ≥0∞} section AeEqOfForallSetIntegralEq theorem ae_const_le_iff_forall_lt_measure_zero {β} [LinearOrder β] [TopologicalSpace β] [OrderTopology β] [FirstCountableTopology β] (f : α → β) (c : β) : (∀ᵐ x ∂μ, c ≤ f x) ↔ ∀ b < c, μ {x | f x ≤ b} = 0 := by rw [ae_iff] push_neg constructor · intro h b hb exact measure_mono_null (fun y hy => (lt_of_le_of_lt hy hb : _)) h intro hc by_cases h : ∀ b, c ≤ b · have : {a : α | f a < c} = ∅ := by apply Set.eq_empty_iff_forall_not_mem.2 fun x hx => ?_ exact (lt_irrefl _ (lt_of_lt_of_le hx (h (f x)))).elim simp [this] by_cases H : ¬IsLUB (Set.Iio c) c · have : c ∈ upperBounds (Set.Iio c) := fun y hy => le_of_lt hy obtain ⟨b, b_up, bc⟩ : ∃ b : β, b ∈ upperBounds (Set.Iio c) ∧ b < c := by simpa [IsLUB, IsLeast, this, lowerBounds] using H exact measure_mono_null (fun x hx => b_up hx) (hc b bc) push_neg at H h obtain ⟨u, _, u_lt, u_lim, -⟩ : ∃ u : ℕ → β, StrictMono u ∧ (∀ n : ℕ, u n < c) ∧ Tendsto u atTop (𝓝 c) ∧ ∀ n : ℕ, u n ∈ Set.Iio c := H.exists_seq_strictMono_tendsto_of_not_mem (lt_irrefl c) h have h_Union : {x | f x < c} = ⋃ n : ℕ, {x | f x ≤ u n} := by ext1 x simp_rw [Set.mem_iUnion, Set.mem_setOf_eq] constructor <;> intro h · obtain ⟨n, hn⟩ := ((tendsto_order.1 u_lim).1 _ h).exists; exact ⟨n, hn.le⟩ · obtain ⟨n, hn⟩ := h; exact hn.trans_lt (u_lt _) rw [h_Union, measure_iUnion_null_iff] intro n exact hc _ (u_lt n) #align measure_theory.ae_const_le_iff_forall_lt_measure_zero MeasureTheory.ae_const_le_iff_forall_lt_measure_zero section Real variable {f : α → ℝ}
Mathlib/MeasureTheory/Function/AEEqOfIntegral.lean
260
284
theorem ae_nonneg_of_forall_setIntegral_nonneg_of_stronglyMeasurable (hfm : StronglyMeasurable f) (hf : Integrable f μ) (hf_zero : ∀ s, MeasurableSet s → μ s < ∞ → 0 ≤ ∫ x in s, f x ∂μ) : 0 ≤ᵐ[μ] f := by
simp_rw [EventuallyLE, Pi.zero_apply] rw [ae_const_le_iff_forall_lt_measure_zero] intro b hb_neg let s := {x | f x ≤ b} have hs : MeasurableSet s := hfm.measurableSet_le stronglyMeasurable_const have mus : μ s < ∞ := Integrable.measure_le_lt_top hf hb_neg have h_int_gt : (∫ x in s, f x ∂μ) ≤ b * (μ s).toReal := by have h_const_le : (∫ x in s, f x ∂μ) ≤ ∫ _ in s, b ∂μ := by refine setIntegral_mono_ae_restrict hf.integrableOn (integrableOn_const.mpr (Or.inr mus)) ?_ rw [EventuallyLE, ae_restrict_iff hs] exact eventually_of_forall fun x hxs => hxs rwa [setIntegral_const, smul_eq_mul, mul_comm] at h_const_le by_contra h refine (lt_self_iff_false (∫ x in s, f x ∂μ)).mp (h_int_gt.trans_lt ?_) refine (mul_neg_iff.mpr (Or.inr ⟨hb_neg, ?_⟩)).trans_le ?_ swap · exact hf_zero s hs mus refine ENNReal.toReal_nonneg.lt_of_ne fun h_eq => h ?_ cases' (ENNReal.toReal_eq_zero_iff _).mp h_eq.symm with hμs_eq_zero hμs_eq_top · exact hμs_eq_zero · exact absurd hμs_eq_top mus.ne
import Mathlib.Control.Monad.Basic import Mathlib.Control.Monad.Writer import Mathlib.Init.Control.Lawful #align_import control.monad.cont from "leanprover-community/mathlib"@"d6814c584384ddf2825ff038e868451a7c956f31" universe u v w u₀ u₁ v₀ v₁ structure MonadCont.Label (α : Type w) (m : Type u → Type v) (β : Type u) where apply : α → m β #align monad_cont.label MonadCont.Label def MonadCont.goto {α β} {m : Type u → Type v} (f : MonadCont.Label α m β) (x : α) := f.apply x #align monad_cont.goto MonadCont.goto class MonadCont (m : Type u → Type v) where callCC : ∀ {α β}, (MonadCont.Label α m β → m α) → m α #align monad_cont MonadCont open MonadCont class LawfulMonadCont (m : Type u → Type v) [Monad m] [MonadCont m] extends LawfulMonad m : Prop where callCC_bind_right {α ω γ} (cmd : m α) (next : Label ω m γ → α → m ω) : (callCC fun f => cmd >>= next f) = cmd >>= fun x => callCC fun f => next f x callCC_bind_left {α} (β) (x : α) (dead : Label α m β → β → m α) : (callCC fun f : Label α m β => goto f x >>= dead f) = pure x callCC_dummy {α β} (dummy : m α) : (callCC fun _ : Label α m β => dummy) = dummy #align is_lawful_monad_cont LawfulMonadCont export LawfulMonadCont (callCC_bind_right callCC_bind_left callCC_dummy) def ContT (r : Type u) (m : Type u → Type v) (α : Type w) := (α → m r) → m r #align cont_t ContT abbrev Cont (r : Type u) (α : Type w) := ContT r id α #align cont Cont namespace ContT export MonadCont (Label goto) variable {r : Type u} {m : Type u → Type v} {α β γ ω : Type w} def run : ContT r m α → (α → m r) → m r := id #align cont_t.run ContT.run def map (f : m r → m r) (x : ContT r m α) : ContT r m α := f ∘ x #align cont_t.map ContT.map theorem run_contT_map_contT (f : m r → m r) (x : ContT r m α) : run (map f x) = f ∘ run x := rfl #align cont_t.run_cont_t_map_cont_t ContT.run_contT_map_contT def withContT (f : (β → m r) → α → m r) (x : ContT r m α) : ContT r m β := fun g => x <| f g #align cont_t.with_cont_t ContT.withContT theorem run_withContT (f : (β → m r) → α → m r) (x : ContT r m α) : run (withContT f x) = run x ∘ f := rfl #align cont_t.run_with_cont_t ContT.run_withContT @[ext] protected theorem ext {x y : ContT r m α} (h : ∀ f, x.run f = y.run f) : x = y := by unfold ContT; ext; apply h #align cont_t.ext ContT.ext instance : Monad (ContT r m) where pure x f := f x bind x f g := x fun i => f i g instance : LawfulMonad (ContT r m) := LawfulMonad.mk' (id_map := by intros; rfl) (pure_bind := by intros; ext; rfl) (bind_assoc := by intros; ext; rfl) def monadLift [Monad m] {α} : m α → ContT r m α := fun x f => x >>= f #align cont_t.monad_lift ContT.monadLift instance [Monad m] : MonadLift m (ContT r m) where monadLift := ContT.monadLift
Mathlib/Control/Monad/Cont.lean
101
105
theorem monadLift_bind [Monad m] [LawfulMonad m] {α β} (x : m α) (f : α → m β) : (monadLift (x >>= f) : ContT r m β) = monadLift x >>= monadLift ∘ f := by
ext simp only [monadLift, MonadLift.monadLift, (· ∘ ·), (· >>= ·), bind_assoc, id, run, ContT.monadLift]
import Mathlib.AlgebraicTopology.SimplicialObject import Mathlib.CategoryTheory.Limits.Shapes.Products #align_import algebraic_topology.split_simplicial_object from "leanprover-community/mathlib"@"dd1f8496baa505636a82748e6b652165ea888733" noncomputable section open CategoryTheory CategoryTheory.Category CategoryTheory.Limits Opposite SimplexCategory open Simplicial universe u variable {C : Type*} [Category C] namespace SimplicialObject namespace Splitting def IndexSet (Δ : SimplexCategoryᵒᵖ) := ΣΔ' : SimplexCategoryᵒᵖ, { α : Δ.unop ⟶ Δ'.unop // Epi α } #align simplicial_object.splitting.index_set SimplicialObject.Splitting.IndexSet namespace IndexSet @[simps] def mk {Δ Δ' : SimplexCategory} (f : Δ ⟶ Δ') [Epi f] : IndexSet (op Δ) := ⟨op Δ', f, inferInstance⟩ #align simplicial_object.splitting.index_set.mk SimplicialObject.Splitting.IndexSet.mk variable {Δ : SimplexCategoryᵒᵖ} (A : IndexSet Δ) def e := A.2.1 #align simplicial_object.splitting.index_set.e SimplicialObject.Splitting.IndexSet.e instance : Epi A.e := A.2.2 theorem ext' : A = ⟨A.1, ⟨A.e, A.2.2⟩⟩ := rfl #align simplicial_object.splitting.index_set.ext' SimplicialObject.Splitting.IndexSet.ext' theorem ext (A₁ A₂ : IndexSet Δ) (h₁ : A₁.1 = A₂.1) (h₂ : A₁.e ≫ eqToHom (by rw [h₁]) = A₂.e) : A₁ = A₂ := by rcases A₁ with ⟨Δ₁, ⟨α₁, hα₁⟩⟩ rcases A₂ with ⟨Δ₂, ⟨α₂, hα₂⟩⟩ simp only at h₁ subst h₁ simp only [eqToHom_refl, comp_id, IndexSet.e] at h₂ simp only [h₂] #align simplicial_object.splitting.index_set.ext SimplicialObject.Splitting.IndexSet.ext instance : Fintype (IndexSet Δ) := Fintype.ofInjective (fun A => ⟨⟨A.1.unop.len, Nat.lt_succ_iff.mpr (len_le_of_epi (inferInstance : Epi A.e))⟩, A.e.toOrderHom⟩ : IndexSet Δ → Sigma fun k : Fin (Δ.unop.len + 1) => Fin (Δ.unop.len + 1) → Fin (k + 1)) (by rintro ⟨Δ₁, α₁⟩ ⟨Δ₂, α₂⟩ h₁ induction' Δ₁ using Opposite.rec with Δ₁ induction' Δ₂ using Opposite.rec with Δ₂ simp only [unop_op, Sigma.mk.inj_iff, Fin.mk.injEq] at h₁ have h₂ : Δ₁ = Δ₂ := by ext1 simpa only [Fin.mk_eq_mk] using h₁.1 subst h₂ refine ext _ _ rfl ?_ ext : 2 exact eq_of_heq h₁.2) variable (Δ) @[simps] def id : IndexSet Δ := ⟨Δ, ⟨𝟙 _, by infer_instance⟩⟩ #align simplicial_object.splitting.index_set.id SimplicialObject.Splitting.IndexSet.id instance : Inhabited (IndexSet Δ) := ⟨id Δ⟩ variable {Δ} @[simp] def EqId : Prop := A = id _ #align simplicial_object.splitting.index_set.eq_id SimplicialObject.Splitting.IndexSet.EqId theorem eqId_iff_eq : A.EqId ↔ A.1 = Δ := by constructor · intro h dsimp at h rw [h] rfl · intro h rcases A with ⟨_, ⟨f, hf⟩⟩ simp only at h subst h refine ext _ _ rfl ?_ haveI := hf simp only [eqToHom_refl, comp_id] exact eq_id_of_epi f #align simplicial_object.splitting.index_set.eq_id_iff_eq SimplicialObject.Splitting.IndexSet.eqId_iff_eq theorem eqId_iff_len_eq : A.EqId ↔ A.1.unop.len = Δ.unop.len := by rw [eqId_iff_eq] constructor · intro h rw [h] · intro h rw [← unop_inj_iff] ext exact h #align simplicial_object.splitting.index_set.eq_id_iff_len_eq SimplicialObject.Splitting.IndexSet.eqId_iff_len_eq theorem eqId_iff_len_le : A.EqId ↔ Δ.unop.len ≤ A.1.unop.len := by rw [eqId_iff_len_eq] constructor · intro h rw [h] · exact le_antisymm (len_le_of_epi (inferInstance : Epi A.e)) #align simplicial_object.splitting.index_set.eq_id_iff_len_le SimplicialObject.Splitting.IndexSet.eqId_iff_len_le
Mathlib/AlgebraicTopology/SplitSimplicialObject.lean
162
171
theorem eqId_iff_mono : A.EqId ↔ Mono A.e := by
constructor · intro h dsimp at h subst h dsimp only [id, e] infer_instance · intro h rw [eqId_iff_len_le] exact len_le_of_mono h
import Mathlib.Logic.Encodable.Lattice import Mathlib.MeasureTheory.MeasurableSpace.Defs #align_import measure_theory.pi_system from "leanprover-community/mathlib"@"98e83c3d541c77cdb7da20d79611a780ff8e7d90" open MeasurableSpace Set open scoped Classical open MeasureTheory def IsPiSystem {α} (C : Set (Set α)) : Prop := ∀ᵉ (s ∈ C) (t ∈ C), (s ∩ t : Set α).Nonempty → s ∩ t ∈ C #align is_pi_system IsPiSystem theorem IsPiSystem.singleton {α} (S : Set α) : IsPiSystem ({S} : Set (Set α)) := by intro s h_s t h_t _ rw [Set.mem_singleton_iff.1 h_s, Set.mem_singleton_iff.1 h_t, Set.inter_self, Set.mem_singleton_iff] #align is_pi_system.singleton IsPiSystem.singleton theorem IsPiSystem.insert_empty {α} {S : Set (Set α)} (h_pi : IsPiSystem S) : IsPiSystem (insert ∅ S) := by intro s hs t ht hst cases' hs with hs hs · simp [hs] · cases' ht with ht ht · simp [ht] · exact Set.mem_insert_of_mem _ (h_pi s hs t ht hst) #align is_pi_system.insert_empty IsPiSystem.insert_empty theorem IsPiSystem.insert_univ {α} {S : Set (Set α)} (h_pi : IsPiSystem S) : IsPiSystem (insert Set.univ S) := by intro s hs t ht hst cases' hs with hs hs · cases' ht with ht ht <;> simp [hs, ht] · cases' ht with ht ht · simp [hs, ht] · exact Set.mem_insert_of_mem _ (h_pi s hs t ht hst) #align is_pi_system.insert_univ IsPiSystem.insert_univ theorem IsPiSystem.comap {α β} {S : Set (Set β)} (h_pi : IsPiSystem S) (f : α → β) : IsPiSystem { s : Set α | ∃ t ∈ S, f ⁻¹' t = s } := by rintro _ ⟨s, hs_mem, rfl⟩ _ ⟨t, ht_mem, rfl⟩ hst rw [← Set.preimage_inter] at hst ⊢ exact ⟨s ∩ t, h_pi s hs_mem t ht_mem (nonempty_of_nonempty_preimage hst), rfl⟩ #align is_pi_system.comap IsPiSystem.comap
Mathlib/MeasureTheory/PiSystem.lean
112
120
theorem isPiSystem_iUnion_of_directed_le {α ι} (p : ι → Set (Set α)) (hp_pi : ∀ n, IsPiSystem (p n)) (hp_directed : Directed (· ≤ ·) p) : IsPiSystem (⋃ n, p n) := by
intro t1 ht1 t2 ht2 h rw [Set.mem_iUnion] at ht1 ht2 ⊢ cases' ht1 with n ht1 cases' ht2 with m ht2 obtain ⟨k, hpnk, hpmk⟩ : ∃ k, p n ≤ p k ∧ p m ≤ p k := hp_directed n m exact ⟨k, hp_pi k t1 (hpnk ht1) t2 (hpmk ht2) h⟩
import Mathlib.Algebra.Lie.Matrix import Mathlib.LinearAlgebra.Matrix.SesquilinearForm import Mathlib.Tactic.NoncommRing #align_import algebra.lie.skew_adjoint from "leanprover-community/mathlib"@"075b3f7d19b9da85a0b54b3e33055a74fc388dec" universe u v w w₁ section SkewAdjointEndomorphisms open LinearMap (BilinForm) variable {R : Type u} {M : Type v} [CommRing R] [AddCommGroup M] [Module R M] variable (B : BilinForm R M) -- Porting note: Changed `(f g)` to `{f g}` for convenience in `skewAdjointLieSubalgebra` theorem LinearMap.BilinForm.isSkewAdjoint_bracket {f g : Module.End R M} (hf : f ∈ B.skewAdjointSubmodule) (hg : g ∈ B.skewAdjointSubmodule) : ⁅f, g⁆ ∈ B.skewAdjointSubmodule := by rw [mem_skewAdjointSubmodule] at * have hfg : IsAdjointPair B B (f * g) (g * f) := by rw [← neg_mul_neg g f]; exact hf.mul hg have hgf : IsAdjointPair B B (g * f) (f * g) := by rw [← neg_mul_neg f g]; exact hg.mul hf change IsAdjointPair B B (f * g - g * f) (-(f * g - g * f)); rw [neg_sub] exact hfg.sub hgf #align bilin_form.is_skew_adjoint_bracket LinearMap.BilinForm.isSkewAdjoint_bracket def skewAdjointLieSubalgebra : LieSubalgebra R (Module.End R M) := { B.skewAdjointSubmodule with lie_mem' := B.isSkewAdjoint_bracket } #align skew_adjoint_lie_subalgebra skewAdjointLieSubalgebra variable {N : Type w} [AddCommGroup N] [Module R N] (e : N ≃ₗ[R] M) def skewAdjointLieSubalgebraEquiv : skewAdjointLieSubalgebra (B.compl₁₂ (↑e : N →ₗ[R] M) ↑e) ≃ₗ⁅R⁆ skewAdjointLieSubalgebra B := by apply LieEquiv.ofSubalgebras _ _ e.lieConj ext f simp only [LieSubalgebra.mem_coe, Submodule.mem_map_equiv, LieSubalgebra.mem_map_submodule, LinearEquiv.coe_coe] exact (LinearMap.isPairSelfAdjoint_equiv (B := -B) (F := B) e f).symm #align skew_adjoint_lie_subalgebra_equiv skewAdjointLieSubalgebraEquiv @[simp] theorem skewAdjointLieSubalgebraEquiv_apply (f : skewAdjointLieSubalgebra (B.compl₁₂ (Qₗ := N) (Qₗ' := N) ↑e ↑e)) : ↑(skewAdjointLieSubalgebraEquiv B e f) = e.lieConj f := by simp [skewAdjointLieSubalgebraEquiv] #align skew_adjoint_lie_subalgebra_equiv_apply skewAdjointLieSubalgebraEquiv_apply @[simp]
Mathlib/Algebra/Lie/SkewAdjoint.lean
84
86
theorem skewAdjointLieSubalgebraEquiv_symm_apply (f : skewAdjointLieSubalgebra B) : ↑((skewAdjointLieSubalgebraEquiv B e).symm f) = e.symm.lieConj f := by
simp [skewAdjointLieSubalgebraEquiv]
import Mathlib.Algebra.Order.Group.TypeTags import Mathlib.FieldTheory.RatFunc.Degree import Mathlib.RingTheory.DedekindDomain.IntegralClosure import Mathlib.RingTheory.IntegrallyClosed import Mathlib.Topology.Algebra.ValuedField #align_import number_theory.function_field from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a" noncomputable section open scoped nonZeroDivisors Polynomial DiscreteValuation variable (Fq F : Type) [Field Fq] [Field F] abbrev FunctionField [Algebra (RatFunc Fq) F] : Prop := FiniteDimensional (RatFunc Fq) F #align function_field FunctionField -- Porting note: Removed `protected` theorem functionField_iff (Fqt : Type*) [Field Fqt] [Algebra Fq[X] Fqt] [IsFractionRing Fq[X] Fqt] [Algebra (RatFunc Fq) F] [Algebra Fqt F] [Algebra Fq[X] F] [IsScalarTower Fq[X] Fqt F] [IsScalarTower Fq[X] (RatFunc Fq) F] : FunctionField Fq F ↔ FiniteDimensional Fqt F := by let e := IsLocalization.algEquiv Fq[X]⁰ (RatFunc Fq) Fqt have : ∀ (c) (x : F), e c • x = c • x := by intro c x rw [Algebra.smul_def, Algebra.smul_def] congr refine congr_fun (f := fun c => algebraMap Fqt F (e c)) ?_ c -- Porting note: Added `(f := _)` refine IsLocalization.ext (nonZeroDivisors Fq[X]) _ _ ?_ ?_ ?_ ?_ ?_ <;> intros <;> simp only [AlgEquiv.map_one, RingHom.map_one, AlgEquiv.map_mul, RingHom.map_mul, AlgEquiv.commutes, ← IsScalarTower.algebraMap_apply] constructor <;> intro h · let b := FiniteDimensional.finBasis (RatFunc Fq) F exact FiniteDimensional.of_fintype_basis (b.mapCoeffs e this) · let b := FiniteDimensional.finBasis Fqt F refine FiniteDimensional.of_fintype_basis (b.mapCoeffs e.symm ?_) intro c x; convert (this (e.symm c) x).symm; simp only [e.apply_symm_apply] #align function_field_iff functionField_iff theorem algebraMap_injective [Algebra Fq[X] F] [Algebra (RatFunc Fq) F] [IsScalarTower Fq[X] (RatFunc Fq) F] : Function.Injective (⇑(algebraMap Fq[X] F)) := by rw [IsScalarTower.algebraMap_eq Fq[X] (RatFunc Fq) F] exact (algebraMap (RatFunc Fq) F).injective.comp (IsFractionRing.injective Fq[X] (RatFunc Fq)) #align algebra_map_injective algebraMap_injective namespace FunctionField def ringOfIntegers [Algebra Fq[X] F] := integralClosure Fq[X] F #align function_field.ring_of_integers FunctionField.ringOfIntegers namespace ringOfIntegers variable [Algebra Fq[X] F] instance : IsDomain (ringOfIntegers Fq F) := (ringOfIntegers Fq F).isDomain instance : IsIntegralClosure (ringOfIntegers Fq F) Fq[X] F := integralClosure.isIntegralClosure _ _ variable [Algebra (RatFunc Fq) F] [IsScalarTower Fq[X] (RatFunc Fq) F]
Mathlib/NumberTheory/FunctionField.lean
113
121
theorem algebraMap_injective : Function.Injective (⇑(algebraMap Fq[X] (ringOfIntegers Fq F))) := by
have hinj : Function.Injective (⇑(algebraMap Fq[X] F)) := by rw [IsScalarTower.algebraMap_eq Fq[X] (RatFunc Fq) F] exact (algebraMap (RatFunc Fq) F).injective.comp (IsFractionRing.injective Fq[X] (RatFunc Fq)) rw [injective_iff_map_eq_zero (algebraMap Fq[X] (↥(ringOfIntegers Fq F)))] intro p hp rw [← Subtype.coe_inj, Subalgebra.coe_zero] at hp rw [injective_iff_map_eq_zero (algebraMap Fq[X] F)] at hinj exact hinj p hp
import Mathlib.Dynamics.Flow import Mathlib.Tactic.Monotonicity #align_import dynamics.omega_limit from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982" open Set Function Filter Topology section omegaLimit variable {τ : Type*} {α : Type*} {β : Type*} {ι : Type*} def omegaLimit [TopologicalSpace β] (f : Filter τ) (ϕ : τ → α → β) (s : Set α) : Set β := ⋂ u ∈ f, closure (image2 ϕ u s) #align omega_limit omegaLimit @[inherit_doc] scoped[omegaLimit] notation "ω" => omegaLimit scoped[omegaLimit] notation "ω⁺" => omegaLimit Filter.atTop scoped[omegaLimit] notation "ω⁻" => omegaLimit Filter.atBot variable [TopologicalSpace β] variable (f : Filter τ) (ϕ : τ → α → β) (s s₁ s₂ : Set α) open omegaLimit theorem omegaLimit_def : ω f ϕ s = ⋂ u ∈ f, closure (image2 ϕ u s) := rfl #align omega_limit_def omegaLimit_def theorem omegaLimit_subset_of_tendsto {m : τ → τ} {f₁ f₂ : Filter τ} (hf : Tendsto m f₁ f₂) : ω f₁ (fun t x ↦ ϕ (m t) x) s ⊆ ω f₂ ϕ s := by refine iInter₂_mono' fun u hu ↦ ⟨m ⁻¹' u, tendsto_def.mp hf _ hu, ?_⟩ rw [← image2_image_left] exact closure_mono (image2_subset (image_preimage_subset _ _) Subset.rfl) #align omega_limit_subset_of_tendsto omegaLimit_subset_of_tendsto theorem omegaLimit_mono_left {f₁ f₂ : Filter τ} (hf : f₁ ≤ f₂) : ω f₁ ϕ s ⊆ ω f₂ ϕ s := omegaLimit_subset_of_tendsto ϕ s (tendsto_id'.2 hf) #align omega_limit_mono_left omegaLimit_mono_left theorem omegaLimit_mono_right {s₁ s₂ : Set α} (hs : s₁ ⊆ s₂) : ω f ϕ s₁ ⊆ ω f ϕ s₂ := iInter₂_mono fun _u _hu ↦ closure_mono (image2_subset Subset.rfl hs) #align omega_limit_mono_right omegaLimit_mono_right theorem isClosed_omegaLimit : IsClosed (ω f ϕ s) := isClosed_iInter fun _u ↦ isClosed_iInter fun _hu ↦ isClosed_closure #align is_closed_omega_limit isClosed_omegaLimit theorem mapsTo_omegaLimit' {α' β' : Type*} [TopologicalSpace β'] {f : Filter τ} {ϕ : τ → α → β} {ϕ' : τ → α' → β'} {ga : α → α'} {s' : Set α'} (hs : MapsTo ga s s') {gb : β → β'} (hg : ∀ᶠ t in f, EqOn (gb ∘ ϕ t) (ϕ' t ∘ ga) s) (hgc : Continuous gb) : MapsTo gb (ω f ϕ s) (ω f ϕ' s') := by simp only [omegaLimit_def, mem_iInter, MapsTo] intro y hy u hu refine map_mem_closure hgc (hy _ (inter_mem hu hg)) (forall_image2_iff.2 fun t ht x hx ↦ ?_) calc gb (ϕ t x) = ϕ' t (ga x) := ht.2 hx _ ∈ image2 ϕ' u s' := mem_image2_of_mem ht.1 (hs hx) #align maps_to_omega_limit' mapsTo_omegaLimit' theorem mapsTo_omegaLimit {α' β' : Type*} [TopologicalSpace β'] {f : Filter τ} {ϕ : τ → α → β} {ϕ' : τ → α' → β'} {ga : α → α'} {s' : Set α'} (hs : MapsTo ga s s') {gb : β → β'} (hg : ∀ t x, gb (ϕ t x) = ϕ' t (ga x)) (hgc : Continuous gb) : MapsTo gb (ω f ϕ s) (ω f ϕ' s') := mapsTo_omegaLimit' _ hs (eventually_of_forall fun t x _hx ↦ hg t x) hgc #align maps_to_omega_limit mapsTo_omegaLimit theorem omegaLimit_image_eq {α' : Type*} (ϕ : τ → α' → β) (f : Filter τ) (g : α → α') : ω f ϕ (g '' s) = ω f (fun t x ↦ ϕ t (g x)) s := by simp only [omegaLimit, image2_image_right] #align omega_limit_image_eq omegaLimit_image_eq theorem omegaLimit_preimage_subset {α' : Type*} (ϕ : τ → α' → β) (s : Set α') (f : Filter τ) (g : α → α') : ω f (fun t x ↦ ϕ t (g x)) (g ⁻¹' s) ⊆ ω f ϕ s := mapsTo_omegaLimit _ (mapsTo_preimage _ _) (fun _t _x ↦ rfl) continuous_id #align omega_limit_preimage_subset omegaLimit_preimage_subset theorem mem_omegaLimit_iff_frequently (y : β) : y ∈ ω f ϕ s ↔ ∀ n ∈ 𝓝 y, ∃ᶠ t in f, (s ∩ ϕ t ⁻¹' n).Nonempty := by simp_rw [frequently_iff, omegaLimit_def, mem_iInter, mem_closure_iff_nhds] constructor · intro h _ hn _ hu rcases h _ hu _ hn with ⟨_, _, _, ht, _, hx, rfl⟩ exact ⟨_, ht, _, hx, by rwa [mem_preimage]⟩ · intro h _ hu _ hn rcases h _ hn hu with ⟨_, ht, _, hx, hϕtx⟩ exact ⟨_, hϕtx, _, ht, _, hx, rfl⟩ #align mem_omega_limit_iff_frequently mem_omegaLimit_iff_frequently theorem mem_omegaLimit_iff_frequently₂ (y : β) : y ∈ ω f ϕ s ↔ ∀ n ∈ 𝓝 y, ∃ᶠ t in f, (ϕ t '' s ∩ n).Nonempty := by simp_rw [mem_omegaLimit_iff_frequently, image_inter_nonempty_iff] #align mem_omega_limit_iff_frequently₂ mem_omegaLimit_iff_frequently₂
Mathlib/Dynamics/OmegaLimit.lean
150
152
theorem mem_omegaLimit_singleton_iff_map_cluster_point (x : α) (y : β) : y ∈ ω f ϕ {x} ↔ MapClusterPt y f fun t ↦ ϕ t x := by
simp_rw [mem_omegaLimit_iff_frequently, mapClusterPt_iff, singleton_inter_nonempty, mem_preimage]
import Mathlib.CategoryTheory.Abelian.Opposite import Mathlib.CategoryTheory.Limits.Preserves.Shapes.Zero import Mathlib.CategoryTheory.Limits.Preserves.Shapes.Kernels import Mathlib.CategoryTheory.Preadditive.LeftExact import Mathlib.CategoryTheory.Adjunction.Limits import Mathlib.Algebra.Homology.Exact import Mathlib.Tactic.TFAE #align_import category_theory.abelian.exact from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a" universe v₁ v₂ u₁ u₂ noncomputable section open CategoryTheory Limits Preadditive variable {C : Type u₁} [Category.{v₁} C] [Abelian C] namespace CategoryTheory namespace Abelian variable {X Y Z : C} (f : X ⟶ Y) (g : Y ⟶ Z) attribute [local instance] hasEqualizers_of_hasKernels
Mathlib/CategoryTheory/Abelian/Exact.lean
57
63
theorem exact_iff_image_eq_kernel : Exact f g ↔ imageSubobject f = kernelSubobject g := by
constructor · intro h have : IsIso (imageToKernel f g h.w) := have := h.epi; isIso_of_mono_of_epi _ refine Subobject.eq_of_comm (asIso (imageToKernel _ _ h.w)) ?_ simp · apply exact_of_image_eq_kernel
import Mathlib.Order.CompleteLattice import Mathlib.Data.Finset.Lattice import Mathlib.CategoryTheory.Limits.Shapes.Pullbacks import Mathlib.CategoryTheory.Category.Preorder import Mathlib.CategoryTheory.Limits.Shapes.Products import Mathlib.CategoryTheory.Limits.Shapes.FiniteLimits #align_import category_theory.limits.lattice from "leanprover-community/mathlib"@"c3019c79074b0619edb4b27553a91b2e82242395" universe w u open CategoryTheory open CategoryTheory.Limits namespace CategoryTheory.Limits.CompleteLattice section Semilattice variable {α : Type u} variable {J : Type w} [SmallCategory J] [FinCategory J] def finiteLimitCone [SemilatticeInf α] [OrderTop α] (F : J ⥤ α) : LimitCone F where cone := { pt := Finset.univ.inf F.obj π := { app := fun j => homOfLE (Finset.inf_le (Fintype.complete _)) } } isLimit := { lift := fun s => homOfLE (Finset.le_inf fun j _ => (s.π.app j).down.down) } #align category_theory.limits.complete_lattice.finite_limit_cone CategoryTheory.Limits.CompleteLattice.finiteLimitCone def finiteColimitCocone [SemilatticeSup α] [OrderBot α] (F : J ⥤ α) : ColimitCocone F where cocone := { pt := Finset.univ.sup F.obj ι := { app := fun i => homOfLE (Finset.le_sup (Fintype.complete _)) } } isColimit := { desc := fun s => homOfLE (Finset.sup_le fun j _ => (s.ι.app j).down.down) } #align category_theory.limits.complete_lattice.finite_colimit_cocone CategoryTheory.Limits.CompleteLattice.finiteColimitCocone -- see Note [lower instance priority] instance (priority := 100) hasFiniteLimits_of_semilatticeInf_orderTop [SemilatticeInf α] [OrderTop α] : HasFiniteLimits α := ⟨by intro J 𝒥₁ 𝒥₂ exact { has_limit := fun F => HasLimit.mk (finiteLimitCone F) }⟩ #align category_theory.limits.complete_lattice.has_finite_limits_of_semilattice_inf_order_top CategoryTheory.Limits.CompleteLattice.hasFiniteLimits_of_semilatticeInf_orderTop -- see Note [lower instance priority] instance (priority := 100) hasFiniteColimits_of_semilatticeSup_orderBot [SemilatticeSup α] [OrderBot α] : HasFiniteColimits α := ⟨by intro J 𝒥₁ 𝒥₂ exact { has_colimit := fun F => HasColimit.mk (finiteColimitCocone F) }⟩ #align category_theory.limits.complete_lattice.has_finite_colimits_of_semilattice_sup_order_bot CategoryTheory.Limits.CompleteLattice.hasFiniteColimits_of_semilatticeSup_orderBot theorem finite_limit_eq_finset_univ_inf [SemilatticeInf α] [OrderTop α] (F : J ⥤ α) : limit F = Finset.univ.inf F.obj := (IsLimit.conePointUniqueUpToIso (limit.isLimit F) (finiteLimitCone F).isLimit).to_eq #align category_theory.limits.complete_lattice.finite_limit_eq_finset_univ_inf CategoryTheory.Limits.CompleteLattice.finite_limit_eq_finset_univ_inf theorem finite_colimit_eq_finset_univ_sup [SemilatticeSup α] [OrderBot α] (F : J ⥤ α) : colimit F = Finset.univ.sup F.obj := (IsColimit.coconePointUniqueUpToIso (colimit.isColimit F) (finiteColimitCocone F).isColimit).to_eq #align category_theory.limits.complete_lattice.finite_colimit_eq_finset_univ_sup CategoryTheory.Limits.CompleteLattice.finite_colimit_eq_finset_univ_sup
Mathlib/CategoryTheory/Limits/Lattice.lean
85
93
theorem finite_product_eq_finset_inf [SemilatticeInf α] [OrderTop α] {ι : Type u} [Fintype ι] (f : ι → α) : ∏ᶜ f = Fintype.elems.inf f := by
trans · exact (IsLimit.conePointUniqueUpToIso (limit.isLimit _) (finiteLimitCone (Discrete.functor f)).isLimit).to_eq change Finset.univ.inf (f ∘ discreteEquiv.toEmbedding) = Fintype.elems.inf f simp only [← Finset.inf_map, Finset.univ_map_equiv_to_embedding] rfl
import Mathlib.SetTheory.Cardinal.Finite #align_import data.set.ncard from "leanprover-community/mathlib"@"74c2af38a828107941029b03839882c5c6f87a04" namespace Set variable {α β : Type*} {s t : Set α} noncomputable def encard (s : Set α) : ℕ∞ := PartENat.withTopEquiv (PartENat.card s) @[simp] theorem encard_univ_coe (s : Set α) : encard (univ : Set s) = encard s := by rw [encard, encard, PartENat.card_congr (Equiv.Set.univ ↑s)] theorem encard_univ (α : Type*) : encard (univ : Set α) = PartENat.withTopEquiv (PartENat.card α) := by rw [encard, PartENat.card_congr (Equiv.Set.univ α)] theorem Finite.encard_eq_coe_toFinset_card (h : s.Finite) : s.encard = h.toFinset.card := by have := h.fintype rw [encard, PartENat.card_eq_coe_fintype_card, PartENat.withTopEquiv_natCast, toFinite_toFinset, toFinset_card] theorem encard_eq_coe_toFinset_card (s : Set α) [Fintype s] : encard s = s.toFinset.card := by have h := toFinite s rw [h.encard_eq_coe_toFinset_card, toFinite_toFinset] theorem encard_coe_eq_coe_finsetCard (s : Finset α) : encard (s : Set α) = s.card := by rw [Finite.encard_eq_coe_toFinset_card (Finset.finite_toSet s)]; simp
Mathlib/Data/Set/Card.lean
85
88
theorem Infinite.encard_eq {s : Set α} (h : s.Infinite) : s.encard = ⊤ := by
have := h.to_subtype rw [encard, ← PartENat.withTopEquiv.symm.injective.eq_iff, Equiv.symm_apply_apply, PartENat.withTopEquiv_symm_top, PartENat.card_eq_top_of_infinite]
import Mathlib.Topology.Algebra.InfiniteSum.Basic import Mathlib.Topology.Algebra.UniformGroup noncomputable section open Filter Finset Function open scoped Topology variable {α β γ δ : Type*} section TopologicalGroup variable [CommGroup α] [TopologicalSpace α] [TopologicalGroup α] variable {f g : β → α} {a a₁ a₂ : α} -- `by simpa using` speeds up elaboration. Why? @[to_additive] theorem HasProd.inv (h : HasProd f a) : HasProd (fun b ↦ (f b)⁻¹) a⁻¹ := by simpa only using h.map (MonoidHom.id α)⁻¹ continuous_inv #align has_sum.neg HasSum.neg @[to_additive] theorem Multipliable.inv (hf : Multipliable f) : Multipliable fun b ↦ (f b)⁻¹ := hf.hasProd.inv.multipliable #align summable.neg Summable.neg @[to_additive] theorem Multipliable.of_inv (hf : Multipliable fun b ↦ (f b)⁻¹) : Multipliable f := by simpa only [inv_inv] using hf.inv #align summable.of_neg Summable.of_neg @[to_additive] theorem multipliable_inv_iff : (Multipliable fun b ↦ (f b)⁻¹) ↔ Multipliable f := ⟨Multipliable.of_inv, Multipliable.inv⟩ #align summable_neg_iff summable_neg_iff @[to_additive] theorem HasProd.div (hf : HasProd f a₁) (hg : HasProd g a₂) : HasProd (fun b ↦ f b / g b) (a₁ / a₂) := by simp only [div_eq_mul_inv] exact hf.mul hg.inv #align has_sum.sub HasSum.sub @[to_additive] theorem Multipliable.div (hf : Multipliable f) (hg : Multipliable g) : Multipliable fun b ↦ f b / g b := (hf.hasProd.div hg.hasProd).multipliable #align summable.sub Summable.sub @[to_additive] theorem Multipliable.trans_div (hg : Multipliable g) (hfg : Multipliable fun b ↦ f b / g b) : Multipliable f := by simpa only [div_mul_cancel] using hfg.mul hg #align summable.trans_sub Summable.trans_sub @[to_additive] theorem multipliable_iff_of_multipliable_div (hfg : Multipliable fun b ↦ f b / g b) : Multipliable f ↔ Multipliable g := ⟨fun hf ↦ hf.trans_div <| by simpa only [inv_div] using hfg.inv, fun hg ↦ hg.trans_div hfg⟩ #align summable_iff_of_summable_sub summable_iff_of_summable_sub @[to_additive] theorem HasProd.update (hf : HasProd f a₁) (b : β) [DecidableEq β] (a : α) : HasProd (update f b a) (a / f b * a₁) := by convert (hasProd_ite_eq b (a / f b)).mul hf with b' by_cases h : b' = b · rw [h, update_same] simp [eq_self_iff_true, if_true, sub_add_cancel] · simp only [h, update_noteq, if_false, Ne, one_mul, not_false_iff] #align has_sum.update HasSum.update @[to_additive] theorem Multipliable.update (hf : Multipliable f) (b : β) [DecidableEq β] (a : α) : Multipliable (update f b a) := (hf.hasProd.update b a).multipliable #align summable.update Summable.update @[to_additive]
Mathlib/Topology/Algebra/InfiniteSum/Group.lean
91
96
theorem HasProd.hasProd_compl_iff {s : Set β} (hf : HasProd (f ∘ (↑) : s → α) a₁) : HasProd (f ∘ (↑) : ↑sᶜ → α) a₂ ↔ HasProd f (a₁ * a₂) := by
refine ⟨fun h ↦ hf.mul_compl h, fun h ↦ ?_⟩ rw [hasProd_subtype_iff_mulIndicator] at hf ⊢ rw [Set.mulIndicator_compl] simpa only [div_eq_mul_inv, mul_inv_cancel_comm] using h.div hf
import Mathlib.Order.ConditionallyCompleteLattice.Basic import Mathlib.Order.LatticeIntervals import Mathlib.Order.Interval.Set.OrdConnected #align_import order.complete_lattice_intervals from "leanprover-community/mathlib"@"207cfac9fcd06138865b5d04f7091e46d9320432" open scoped Classical open Set variable {ι : Sort*} {α : Type*} (s : Set α) section SupSet variable [Preorder α] [SupSet α] noncomputable def subsetSupSet [Inhabited s] : SupSet s where sSup t := if ht : t.Nonempty ∧ BddAbove t ∧ sSup ((↑) '' t : Set α) ∈ s then ⟨sSup ((↑) '' t : Set α), ht.2.2⟩ else default #align subset_has_Sup subsetSupSet attribute [local instance] subsetSupSet @[simp] theorem subset_sSup_def [Inhabited s] : @sSup s _ = fun t => if ht : t.Nonempty ∧ BddAbove t ∧ sSup ((↑) '' t : Set α) ∈ s then ⟨sSup ((↑) '' t : Set α), ht.2.2⟩ else default := rfl #align subset_Sup_def subset_sSup_def
Mathlib/Order/CompleteLatticeIntervals.lean
57
59
theorem subset_sSup_of_within [Inhabited s] {t : Set s} (h' : t.Nonempty) (h'' : BddAbove t) (h : sSup ((↑) '' t : Set α) ∈ s) : sSup ((↑) '' t : Set α) = (@sSup s _ t : α) := by
simp [dif_pos, h, h', h'']
import Mathlib.AlgebraicTopology.DoldKan.GammaCompN import Mathlib.AlgebraicTopology.DoldKan.NReflectsIso #align_import algebraic_topology.dold_kan.n_comp_gamma from "leanprover-community/mathlib"@"32a7e535287f9c73f2e4d2aef306a39190f0b504" noncomputable section open CategoryTheory CategoryTheory.Category CategoryTheory.Limits CategoryTheory.Idempotents SimplexCategory Opposite SimplicialObject Simplicial DoldKan namespace AlgebraicTopology namespace DoldKan variable {C : Type*} [Category C] [Preadditive C]
Mathlib/AlgebraicTopology/DoldKan/NCompGamma.lean
38
78
theorem PInfty_comp_map_mono_eq_zero (X : SimplicialObject C) {n : ℕ} {Δ' : SimplexCategory} (i : Δ' ⟶ [n]) [hi : Mono i] (h₁ : Δ'.len ≠ n) (h₂ : ¬Isδ₀ i) : PInfty.f n ≫ X.map i.op = 0 := by
induction' Δ' using SimplexCategory.rec with m obtain ⟨k, hk⟩ := Nat.exists_eq_add_of_lt (len_lt_of_mono i fun h => by rw [← h] at h₁ exact h₁ rfl) simp only [len_mk] at hk rcases k with _|k · change n = m + 1 at hk subst hk obtain ⟨j, rfl⟩ := eq_δ_of_mono i rw [Isδ₀.iff] at h₂ have h₃ : 1 ≤ (j : ℕ) := by by_contra h exact h₂ (by simpa only [Fin.ext_iff, not_le, Nat.lt_one_iff] using h) exact (HigherFacesVanish.of_P (m + 1) m).comp_δ_eq_zero j h₂ (by omega) · simp only [Nat.succ_eq_add_one, ← add_assoc] at hk clear h₂ hi subst hk obtain ⟨j₁ : Fin (_ + 1), i, rfl⟩ := eq_comp_δ_of_not_surjective i fun h => by have h' := len_le_of_epi (SimplexCategory.epi_iff_surjective.2 h) dsimp at h' omega obtain ⟨j₂, i, rfl⟩ := eq_comp_δ_of_not_surjective i fun h => by have h' := len_le_of_epi (SimplexCategory.epi_iff_surjective.2 h) dsimp at h' omega by_cases hj₁ : j₁ = 0 · subst hj₁ rw [assoc, ← SimplexCategory.δ_comp_δ'' (Fin.zero_le _)] simp only [op_comp, X.map_comp, assoc, PInfty_f] erw [(HigherFacesVanish.of_P _ _).comp_δ_eq_zero_assoc _ j₂.succ_ne_zero, zero_comp] simp only [Nat.succ_eq_add_one, Nat.add, Fin.succ] omega · simp only [op_comp, X.map_comp, assoc, PInfty_f] erw [(HigherFacesVanish.of_P _ _).comp_δ_eq_zero_assoc _ hj₁, zero_comp] by_contra exact hj₁ (by simp only [Fin.ext_iff, Fin.val_zero]; linarith)
import Mathlib.Analysis.InnerProductSpace.Basic import Mathlib.Analysis.SpecialFunctions.Trigonometric.Inverse #align_import geometry.euclidean.angle.unoriented.basic from "leanprover-community/mathlib"@"46b633fd842bef9469441c0209906f6dddd2b4f5" assert_not_exists HasFDerivAt assert_not_exists ConformalAt noncomputable section open Real Set open Real open RealInnerProductSpace namespace InnerProductGeometry variable {V : Type*} [NormedAddCommGroup V] [InnerProductSpace ℝ V] {x y : V} def angle (x y : V) : ℝ := Real.arccos (⟪x, y⟫ / (‖x‖ * ‖y‖)) #align inner_product_geometry.angle InnerProductGeometry.angle theorem continuousAt_angle {x : V × V} (hx1 : x.1 ≠ 0) (hx2 : x.2 ≠ 0) : ContinuousAt (fun y : V × V => angle y.1 y.2) x := Real.continuous_arccos.continuousAt.comp <| continuous_inner.continuousAt.div ((continuous_norm.comp continuous_fst).mul (continuous_norm.comp continuous_snd)).continuousAt (by simp [hx1, hx2]) #align inner_product_geometry.continuous_at_angle InnerProductGeometry.continuousAt_angle theorem angle_smul_smul {c : ℝ} (hc : c ≠ 0) (x y : V) : angle (c • x) (c • y) = angle x y := by have : c * c ≠ 0 := mul_ne_zero hc hc rw [angle, angle, real_inner_smul_left, inner_smul_right, norm_smul, norm_smul, Real.norm_eq_abs, mul_mul_mul_comm _ ‖x‖, abs_mul_abs_self, ← mul_assoc c c, mul_div_mul_left _ _ this] #align inner_product_geometry.angle_smul_smul InnerProductGeometry.angle_smul_smul @[simp] theorem _root_.LinearIsometry.angle_map {E F : Type*} [NormedAddCommGroup E] [NormedAddCommGroup F] [InnerProductSpace ℝ E] [InnerProductSpace ℝ F] (f : E →ₗᵢ[ℝ] F) (u v : E) : angle (f u) (f v) = angle u v := by rw [angle, angle, f.inner_map_map, f.norm_map, f.norm_map] #align linear_isometry.angle_map LinearIsometry.angle_map @[simp, norm_cast] theorem _root_.Submodule.angle_coe {s : Submodule ℝ V} (x y : s) : angle (x : V) (y : V) = angle x y := s.subtypeₗᵢ.angle_map x y #align submodule.angle_coe Submodule.angle_coe theorem cos_angle (x y : V) : Real.cos (angle x y) = ⟪x, y⟫ / (‖x‖ * ‖y‖) := Real.cos_arccos (abs_le.mp (abs_real_inner_div_norm_mul_norm_le_one x y)).1 (abs_le.mp (abs_real_inner_div_norm_mul_norm_le_one x y)).2 #align inner_product_geometry.cos_angle InnerProductGeometry.cos_angle theorem angle_comm (x y : V) : angle x y = angle y x := by unfold angle rw [real_inner_comm, mul_comm] #align inner_product_geometry.angle_comm InnerProductGeometry.angle_comm @[simp] theorem angle_neg_neg (x y : V) : angle (-x) (-y) = angle x y := by unfold angle rw [inner_neg_neg, norm_neg, norm_neg] #align inner_product_geometry.angle_neg_neg InnerProductGeometry.angle_neg_neg theorem angle_nonneg (x y : V) : 0 ≤ angle x y := Real.arccos_nonneg _ #align inner_product_geometry.angle_nonneg InnerProductGeometry.angle_nonneg theorem angle_le_pi (x y : V) : angle x y ≤ π := Real.arccos_le_pi _ #align inner_product_geometry.angle_le_pi InnerProductGeometry.angle_le_pi theorem angle_neg_right (x y : V) : angle x (-y) = π - angle x y := by unfold angle rw [← Real.arccos_neg, norm_neg, inner_neg_right, neg_div] #align inner_product_geometry.angle_neg_right InnerProductGeometry.angle_neg_right theorem angle_neg_left (x y : V) : angle (-x) y = π - angle x y := by rw [← angle_neg_neg, neg_neg, angle_neg_right] #align inner_product_geometry.angle_neg_left InnerProductGeometry.angle_neg_left proof_wanted angle_triangle (x y z : V) : angle x z ≤ angle x y + angle y z @[simp] theorem angle_zero_left (x : V) : angle 0 x = π / 2 := by unfold angle rw [inner_zero_left, zero_div, Real.arccos_zero] #align inner_product_geometry.angle_zero_left InnerProductGeometry.angle_zero_left @[simp]
Mathlib/Geometry/Euclidean/Angle/Unoriented/Basic.lean
127
129
theorem angle_zero_right (x : V) : angle x 0 = π / 2 := by
unfold angle rw [inner_zero_right, zero_div, Real.arccos_zero]
import Mathlib.Data.Countable.Basic import Mathlib.Data.Fin.VecNotation import Mathlib.Order.Disjointed import Mathlib.MeasureTheory.OuterMeasure.Defs #align_import measure_theory.measure.outer_measure from "leanprover-community/mathlib"@"343e80208d29d2d15f8050b929aa50fe4ce71b55" noncomputable section open Set Function Filter open scoped Classical NNReal Topology ENNReal namespace MeasureTheory section OuterMeasureClass variable {α ι F : Type*} [FunLike F (Set α) ℝ≥0∞] [OuterMeasureClass F α] {μ : F} {s t : Set α} @[simp] theorem measure_empty : μ ∅ = 0 := OuterMeasureClass.measure_empty μ #align measure_theory.measure_empty MeasureTheory.measure_empty @[mono, gcongr] theorem measure_mono (h : s ⊆ t) : μ s ≤ μ t := OuterMeasureClass.measure_mono μ h #align measure_theory.measure_mono MeasureTheory.measure_mono theorem measure_mono_null (h : s ⊆ t) (ht : μ t = 0) : μ s = 0 := eq_bot_mono (measure_mono h) ht #align measure_theory.measure_mono_null MeasureTheory.measure_mono_null theorem measure_pos_of_superset (h : s ⊆ t) (hs : μ s ≠ 0) : 0 < μ t := hs.bot_lt.trans_le (measure_mono h) theorem measure_iUnion_le [Countable ι] (s : ι → Set α) : μ (⋃ i, s i) ≤ ∑' i, μ (s i) := by refine rel_iSup_tsum μ measure_empty (· ≤ ·) (fun t ↦ ?_) _ calc μ (⋃ i, t i) = μ (⋃ i, disjointed t i) := by rw [iUnion_disjointed] _ ≤ ∑' i, μ (disjointed t i) := OuterMeasureClass.measure_iUnion_nat_le _ _ (disjoint_disjointed _) _ ≤ ∑' i, μ (t i) := by gcongr; apply disjointed_subset #align measure_theory.measure_Union_le MeasureTheory.measure_iUnion_le theorem measure_biUnion_le {I : Set ι} (μ : F) (hI : I.Countable) (s : ι → Set α) : μ (⋃ i ∈ I, s i) ≤ ∑' i : I, μ (s i) := by have := hI.to_subtype rw [biUnion_eq_iUnion] apply measure_iUnion_le #align measure_theory.measure_bUnion_le MeasureTheory.measure_biUnion_le theorem measure_biUnion_finset_le (I : Finset ι) (s : ι → Set α) : μ (⋃ i ∈ I, s i) ≤ ∑ i ∈ I, μ (s i) := (measure_biUnion_le μ I.countable_toSet s).trans_eq <| I.tsum_subtype (μ <| s ·) #align measure_theory.measure_bUnion_finset_le MeasureTheory.measure_biUnion_finset_le theorem measure_iUnion_fintype_le [Fintype ι] (μ : F) (s : ι → Set α) : μ (⋃ i, s i) ≤ ∑ i, μ (s i) := by simpa using measure_biUnion_finset_le Finset.univ s #align measure_theory.measure_Union_fintype_le MeasureTheory.measure_iUnion_fintype_le theorem measure_union_le (s t : Set α) : μ (s ∪ t) ≤ μ s + μ t := by simpa [union_eq_iUnion] using measure_iUnion_fintype_le μ (cond · s t) #align measure_theory.measure_union_le MeasureTheory.measure_union_le theorem measure_le_inter_add_diff (μ : F) (s t : Set α) : μ s ≤ μ (s ∩ t) + μ (s \ t) := by simpa using measure_union_le (s ∩ t) (s \ t) theorem measure_diff_null (ht : μ t = 0) : μ (s \ t) = μ s := (measure_mono diff_subset).antisymm <| calc μ s ≤ μ (s ∩ t) + μ (s \ t) := measure_le_inter_add_diff _ _ _ _ ≤ μ t + μ (s \ t) := by gcongr; apply inter_subset_right _ = μ (s \ t) := by simp [ht] #align measure_theory.measure_diff_null MeasureTheory.measure_diff_null
Mathlib/MeasureTheory/OuterMeasure/Basic.lean
103
107
theorem measure_biUnion_null_iff {I : Set ι} (hI : I.Countable) {s : ι → Set α} : μ (⋃ i ∈ I, s i) = 0 ↔ ∀ i ∈ I, μ (s i) = 0 := by
refine ⟨fun h i hi ↦ measure_mono_null (subset_biUnion_of_mem hi) h, fun h ↦ ?_⟩ have _ := hI.to_subtype simpa [h] using measure_iUnion_le (μ := μ) fun x : I ↦ s x
import Mathlib.LinearAlgebra.Matrix.Charpoly.Coeff import Mathlib.LinearAlgebra.Matrix.ToLin import Mathlib.RingTheory.PowerBasis #align_import linear_algebra.matrix.charpoly.minpoly from "leanprover-community/mathlib"@"7ae139f966795f684fc689186f9ccbaedd31bf31" noncomputable section universe u v w open Polynomial Matrix variable {R : Type u} [CommRing R] variable {n : Type v} [DecidableEq n] [Fintype n] variable {N : Type w} [AddCommGroup N] [Module R N] open Finset section PowerBasis open Algebra
Mathlib/LinearAlgebra/Matrix/Charpoly/Minpoly.lean
83
92
theorem charpoly_leftMulMatrix {S : Type*} [Ring S] [Algebra R S] (h : PowerBasis R S) : (leftMulMatrix h.basis h.gen).charpoly = minpoly R h.gen := by
cases subsingleton_or_nontrivial R; · apply Subsingleton.elim apply minpoly.unique' R h.gen (charpoly_monic _) · apply (injective_iff_map_eq_zero (G := S) (leftMulMatrix _)).mp (leftMulMatrix_injective h.basis) rw [← Polynomial.aeval_algHom_apply, aeval_self_charpoly] refine fun q hq => or_iff_not_imp_left.2 fun h0 => ?_ rw [Matrix.charpoly_degree_eq_dim, Fintype.card_fin] at hq contrapose! hq; exact h.dim_le_degree_of_root h0 hq
import Mathlib.Topology.Algebra.InfiniteSum.Basic import Mathlib.Topology.Algebra.UniformGroup noncomputable section open Filter Finset Function open scoped Topology variable {α β γ δ : Type*} section TopologicalGroup variable [CommGroup α] [TopologicalSpace α] [TopologicalGroup α] variable {f g : β → α} {a a₁ a₂ : α} -- `by simpa using` speeds up elaboration. Why? @[to_additive]
Mathlib/Topology/Algebra/InfiniteSum/Group.lean
30
31
theorem HasProd.inv (h : HasProd f a) : HasProd (fun b ↦ (f b)⁻¹) a⁻¹ := by
simpa only using h.map (MonoidHom.id α)⁻¹ continuous_inv
import Mathlib.CategoryTheory.Sites.Sieves import Mathlib.CategoryTheory.Limits.Shapes.Pullbacks import Mathlib.CategoryTheory.Limits.Shapes.Multiequalizer import Mathlib.CategoryTheory.Category.Preorder import Mathlib.Order.Copy import Mathlib.Data.Set.Subsingleton #align_import category_theory.sites.grothendieck from "leanprover-community/mathlib"@"14b69e9f3c16630440a2cbd46f1ddad0d561dee7" universe v₁ u₁ v u namespace CategoryTheory open CategoryTheory Category variable (C : Type u) [Category.{v} C] structure GrothendieckTopology where sieves : ∀ X : C, Set (Sieve X) top_mem' : ∀ X, ⊤ ∈ sieves X pullback_stable' : ∀ ⦃X Y : C⦄ ⦃S : Sieve X⦄ (f : Y ⟶ X), S ∈ sieves X → S.pullback f ∈ sieves Y transitive' : ∀ ⦃X⦄ ⦃S : Sieve X⦄ (_ : S ∈ sieves X) (R : Sieve X), (∀ ⦃Y⦄ ⦃f : Y ⟶ X⦄, S f → R.pullback f ∈ sieves Y) → R ∈ sieves X #align category_theory.grothendieck_topology CategoryTheory.GrothendieckTopology namespace GrothendieckTopology instance : CoeFun (GrothendieckTopology C) fun _ => ∀ X : C, Set (Sieve X) := ⟨sieves⟩ variable {C} variable {X Y : C} {S R : Sieve X} variable (J : GrothendieckTopology C) @[ext] theorem ext {J₁ J₂ : GrothendieckTopology C} (h : (J₁ : ∀ X : C, Set (Sieve X)) = J₂) : J₁ = J₂ := by cases J₁ cases J₂ congr #align category_theory.grothendieck_topology.ext CategoryTheory.GrothendieckTopology.ext @[simp] theorem top_mem (X : C) : ⊤ ∈ J X := J.top_mem' X #align category_theory.grothendieck_topology.top_mem CategoryTheory.GrothendieckTopology.top_mem @[simp] theorem pullback_stable (f : Y ⟶ X) (hS : S ∈ J X) : S.pullback f ∈ J Y := J.pullback_stable' f hS #align category_theory.grothendieck_topology.pullback_stable CategoryTheory.GrothendieckTopology.pullback_stable theorem transitive (hS : S ∈ J X) (R : Sieve X) (h : ∀ ⦃Y⦄ ⦃f : Y ⟶ X⦄, S f → R.pullback f ∈ J Y) : R ∈ J X := J.transitive' hS R h #align category_theory.grothendieck_topology.transitive CategoryTheory.GrothendieckTopology.transitive theorem covering_of_eq_top : S = ⊤ → S ∈ J X := fun h => h.symm ▸ J.top_mem X #align category_theory.grothendieck_topology.covering_of_eq_top CategoryTheory.GrothendieckTopology.covering_of_eq_top theorem superset_covering (Hss : S ≤ R) (sjx : S ∈ J X) : R ∈ J X := by apply J.transitive sjx R fun Y f hf => _ intros Y f hf apply covering_of_eq_top rw [← top_le_iff, ← S.pullback_eq_top_of_mem hf] apply Sieve.pullback_monotone _ Hss #align category_theory.grothendieck_topology.superset_covering CategoryTheory.GrothendieckTopology.superset_covering theorem intersection_covering (rj : R ∈ J X) (sj : S ∈ J X) : R ⊓ S ∈ J X := by apply J.transitive rj _ fun Y f Hf => _ intros Y f hf rw [Sieve.pullback_inter, R.pullback_eq_top_of_mem hf] simp [sj] #align category_theory.grothendieck_topology.intersection_covering CategoryTheory.GrothendieckTopology.intersection_covering @[simp] theorem intersection_covering_iff : R ⊓ S ∈ J X ↔ R ∈ J X ∧ S ∈ J X := ⟨fun h => ⟨J.superset_covering inf_le_left h, J.superset_covering inf_le_right h⟩, fun t => intersection_covering _ t.1 t.2⟩ #align category_theory.grothendieck_topology.intersection_covering_iff CategoryTheory.GrothendieckTopology.intersection_covering_iff theorem bind_covering {S : Sieve X} {R : ∀ ⦃Y : C⦄ ⦃f : Y ⟶ X⦄, S f → Sieve Y} (hS : S ∈ J X) (hR : ∀ ⦃Y⦄ ⦃f : Y ⟶ X⦄ (H : S f), R H ∈ J Y) : Sieve.bind S R ∈ J X := J.transitive hS _ fun _ f hf => superset_covering J (Sieve.le_pullback_bind S R f hf) (hR hf) #align category_theory.grothendieck_topology.bind_covering CategoryTheory.GrothendieckTopology.bind_covering def Covers (S : Sieve X) (f : Y ⟶ X) : Prop := S.pullback f ∈ J Y #align category_theory.grothendieck_topology.covers CategoryTheory.GrothendieckTopology.Covers theorem covers_iff (S : Sieve X) (f : Y ⟶ X) : J.Covers S f ↔ S.pullback f ∈ J Y := Iff.rfl #align category_theory.grothendieck_topology.covers_iff CategoryTheory.GrothendieckTopology.covers_iff theorem covering_iff_covers_id (S : Sieve X) : S ∈ J X ↔ J.Covers S (𝟙 X) := by simp [covers_iff] #align category_theory.grothendieck_topology.covering_iff_covers_id CategoryTheory.GrothendieckTopology.covering_iff_covers_id
Mathlib/CategoryTheory/Sites/Grothendieck.lean
191
193
theorem arrow_max (f : Y ⟶ X) (S : Sieve X) (hf : S f) : J.Covers S f := by
rw [Covers, (Sieve.pullback_eq_top_iff_mem f).1 hf] apply J.top_mem
import Mathlib.Analysis.Normed.Group.Basic #align_import information_theory.hamming from "leanprover-community/mathlib"@"17ef379e997badd73e5eabb4d38f11919ab3c4b3" section HammingDistNorm open Finset Function variable {α ι : Type*} {β : ι → Type*} [Fintype ι] [∀ i, DecidableEq (β i)] variable {γ : ι → Type*} [∀ i, DecidableEq (γ i)] def hammingDist (x y : ∀ i, β i) : ℕ := (univ.filter fun i => x i ≠ y i).card #align hamming_dist hammingDist @[simp] theorem hammingDist_self (x : ∀ i, β i) : hammingDist x x = 0 := by rw [hammingDist, card_eq_zero, filter_eq_empty_iff] exact fun _ _ H => H rfl #align hamming_dist_self hammingDist_self theorem hammingDist_nonneg {x y : ∀ i, β i} : 0 ≤ hammingDist x y := zero_le _ #align hamming_dist_nonneg hammingDist_nonneg theorem hammingDist_comm (x y : ∀ i, β i) : hammingDist x y = hammingDist y x := by simp_rw [hammingDist, ne_comm] #align hamming_dist_comm hammingDist_comm theorem hammingDist_triangle (x y z : ∀ i, β i) : hammingDist x z ≤ hammingDist x y + hammingDist y z := by classical unfold hammingDist refine le_trans (card_mono ?_) (card_union_le _ _) rw [← filter_or] exact monotone_filter_right _ fun i h ↦ (h.ne_or_ne _).imp_right Ne.symm #align hamming_dist_triangle hammingDist_triangle theorem hammingDist_triangle_left (x y z : ∀ i, β i) : hammingDist x y ≤ hammingDist z x + hammingDist z y := by rw [hammingDist_comm z] exact hammingDist_triangle _ _ _ #align hamming_dist_triangle_left hammingDist_triangle_left theorem hammingDist_triangle_right (x y z : ∀ i, β i) : hammingDist x y ≤ hammingDist x z + hammingDist y z := by rw [hammingDist_comm y] exact hammingDist_triangle _ _ _ #align hamming_dist_triangle_right hammingDist_triangle_right theorem swap_hammingDist : swap (@hammingDist _ β _ _) = hammingDist := by funext x y exact hammingDist_comm _ _ #align swap_hamming_dist swap_hammingDist
Mathlib/InformationTheory/Hamming.lean
91
93
theorem eq_of_hammingDist_eq_zero {x y : ∀ i, β i} : hammingDist x y = 0 → x = y := by
simp_rw [hammingDist, card_eq_zero, filter_eq_empty_iff, Classical.not_not, funext_iff, mem_univ, forall_true_left, imp_self]
import Mathlib.Algebra.Polynomial.AlgebraMap import Mathlib.Algebra.Polynomial.BigOperators import Mathlib.Algebra.Polynomial.Degree.Lemmas import Mathlib.Algebra.Polynomial.Div #align_import data.polynomial.ring_division from "leanprover-community/mathlib"@"8efcf8022aac8e01df8d302dcebdbc25d6a886c8" noncomputable section open Polynomial open Finset namespace Polynomial universe u v w z variable {R : Type u} {S : Type v} {T : Type w} {a b : R} {n : ℕ} section NoZeroDivisors variable [Semiring R] [NoZeroDivisors R] {p q : R[X]} instance : NoZeroDivisors R[X] where eq_zero_or_eq_zero_of_mul_eq_zero h := by rw [← leadingCoeff_eq_zero, ← leadingCoeff_eq_zero] refine eq_zero_or_eq_zero_of_mul_eq_zero ?_ rw [← leadingCoeff_zero, ← leadingCoeff_mul, h] theorem natDegree_mul (hp : p ≠ 0) (hq : q ≠ 0) : (p*q).natDegree = p.natDegree + q.natDegree := by rw [← Nat.cast_inj (R := WithBot ℕ), ← degree_eq_natDegree (mul_ne_zero hp hq), Nat.cast_add, ← degree_eq_natDegree hp, ← degree_eq_natDegree hq, degree_mul] #align polynomial.nat_degree_mul Polynomial.natDegree_mul theorem trailingDegree_mul : (p * q).trailingDegree = p.trailingDegree + q.trailingDegree := by by_cases hp : p = 0 · rw [hp, zero_mul, trailingDegree_zero, top_add] by_cases hq : q = 0 · rw [hq, mul_zero, trailingDegree_zero, add_top] · rw [trailingDegree_eq_natTrailingDegree hp, trailingDegree_eq_natTrailingDegree hq, trailingDegree_eq_natTrailingDegree (mul_ne_zero hp hq), natTrailingDegree_mul hp hq] apply WithTop.coe_add #align polynomial.trailing_degree_mul Polynomial.trailingDegree_mul @[simp] theorem natDegree_pow (p : R[X]) (n : ℕ) : natDegree (p ^ n) = n * natDegree p := by classical obtain rfl | hp := eq_or_ne p 0 · obtain rfl | hn := eq_or_ne n 0 <;> simp [*] exact natDegree_pow' $ by rw [← leadingCoeff_pow, Ne, leadingCoeff_eq_zero]; exact pow_ne_zero _ hp #align polynomial.nat_degree_pow Polynomial.natDegree_pow
Mathlib/Algebra/Polynomial/RingDivision.lean
148
153
theorem degree_le_mul_left (p : R[X]) (hq : q ≠ 0) : degree p ≤ degree (p * q) := by
classical exact if hp : p = 0 then by simp only [hp, zero_mul, le_refl] else by rw [degree_mul, degree_eq_natDegree hp, degree_eq_natDegree hq]; exact WithBot.coe_le_coe.2 (Nat.le_add_right _ _)
import Mathlib.Analysis.SpecialFunctions.Trigonometric.Bounds #align_import data.real.pi.bounds from "leanprover-community/mathlib"@"402f8982dddc1864bd703da2d6e2ee304a866973" -- Porting note: needed to add a lot of type ascriptions for lean to interpret numbers as reals. open scoped Real namespace Real theorem pi_gt_sqrtTwoAddSeries (n : ℕ) : (2 : ℝ) ^ (n + 1) * √(2 - sqrtTwoAddSeries 0 n) < π := by have : √(2 - sqrtTwoAddSeries 0 n) / (2 : ℝ) * (2 : ℝ) ^ (n + 2) < π := by rw [← lt_div_iff, ← sin_pi_over_two_pow_succ] focus apply sin_lt apply div_pos pi_pos all_goals apply pow_pos; norm_num apply lt_of_le_of_lt (le_of_eq _) this rw [pow_succ' _ (n + 1), ← mul_assoc, div_mul_cancel₀, mul_comm]; norm_num #align real.pi_gt_sqrt_two_add_series Real.pi_gt_sqrtTwoAddSeries theorem pi_lt_sqrtTwoAddSeries (n : ℕ) : π < (2 : ℝ) ^ (n + 1) * √(2 - sqrtTwoAddSeries 0 n) + 1 / (4 : ℝ) ^ n := by have : π < (√(2 - sqrtTwoAddSeries 0 n) / (2 : ℝ) + (1 : ℝ) / ((2 : ℝ) ^ n) ^ 3 / 4) * (2 : ℝ) ^ (n + 2) := by rw [← div_lt_iff (by norm_num), ← sin_pi_over_two_pow_succ] refine lt_of_lt_of_le (lt_add_of_sub_right_lt (sin_gt_sub_cube ?_ ?_)) ?_ · apply div_pos pi_pos; apply pow_pos; norm_num · rw [div_le_iff'] · refine le_trans pi_le_four ?_ simp only [show (4 : ℝ) = (2 : ℝ) ^ 2 by norm_num, mul_one] apply pow_le_pow_right (by norm_num) apply le_add_of_nonneg_left; apply Nat.zero_le · apply pow_pos; norm_num apply add_le_add_left; rw [div_le_div_right (by norm_num)] rw [le_div_iff (by norm_num), ← mul_pow] refine le_trans ?_ (le_of_eq (one_pow 3)); apply pow_le_pow_left · apply le_of_lt; apply mul_pos · apply div_pos pi_pos; apply pow_pos; norm_num · apply pow_pos; norm_num · rw [← le_div_iff (by norm_num)] refine le_trans ((div_le_div_right ?_).mpr pi_le_four) ?_ · apply pow_pos; norm_num · simp only [pow_succ', ← div_div, one_div] -- Porting note: removed `convert le_rfl` norm_num apply lt_of_lt_of_le this (le_of_eq _); rw [add_mul]; congr 1 · ring simp only [show (4 : ℝ) = 2 ^ 2 by norm_num, ← pow_mul, div_div, ← pow_add] rw [one_div, one_div, inv_mul_eq_iff_eq_mul₀, eq_comm, mul_inv_eq_iff_eq_mul₀, ← pow_add] · rw [add_assoc, Nat.mul_succ, add_comm, add_comm n, add_assoc, mul_comm n] all_goals norm_num #align real.pi_lt_sqrt_two_add_series Real.pi_lt_sqrtTwoAddSeries theorem pi_lower_bound_start (n : ℕ) {a} (h : sqrtTwoAddSeries ((0 : ℕ) / (1 : ℕ)) n ≤ (2 : ℝ) - (a / (2 : ℝ) ^ (n + 1)) ^ 2) : a < π := by refine lt_of_le_of_lt ?_ (pi_gt_sqrtTwoAddSeries n); rw [mul_comm] refine (div_le_iff (pow_pos (by norm_num) _ : (0 : ℝ) < _)).mp (le_sqrt_of_sq_le ?_) rwa [le_sub_comm, show (0 : ℝ) = (0 : ℕ) / (1 : ℕ) by rw [Nat.cast_zero, zero_div]] #align real.pi_lower_bound_start Real.pi_lower_bound_start
Mathlib/Data/Real/Pi/Bounds.lean
85
93
theorem sqrtTwoAddSeries_step_up (c d : ℕ) {a b n : ℕ} {z : ℝ} (hz : sqrtTwoAddSeries (c / d) n ≤ z) (hb : 0 < b) (hd : 0 < d) (h : (2 * b + a) * d ^ 2 ≤ c ^ 2 * b) : sqrtTwoAddSeries (a / b) (n + 1) ≤ z := by
refine le_trans ?_ hz; rw [sqrtTwoAddSeries_succ]; apply sqrtTwoAddSeries_monotone_left have hb' : 0 < (b : ℝ) := Nat.cast_pos.2 hb have hd' : 0 < (d : ℝ) := Nat.cast_pos.2 hd rw [sqrt_le_left (div_nonneg c.cast_nonneg d.cast_nonneg), div_pow, add_div_eq_mul_add_div _ _ (ne_of_gt hb'), div_le_div_iff hb' (pow_pos hd' _)] exact mod_cast h
import Mathlib.AlgebraicTopology.DoldKan.FunctorN import Mathlib.AlgebraicTopology.DoldKan.Decomposition import Mathlib.CategoryTheory.Idempotents.HomologicalComplex import Mathlib.CategoryTheory.Idempotents.KaroubiKaroubi #align_import algebraic_topology.dold_kan.n_reflects_iso from "leanprover-community/mathlib"@"32a7e535287f9c73f2e4d2aef306a39190f0b504" open CategoryTheory CategoryTheory.Category CategoryTheory.Idempotents Opposite Simplicial namespace AlgebraicTopology namespace DoldKan variable {C : Type*} [Category C] [Preadditive C] open MorphComponents instance : (N₁ : SimplicialObject C ⥤ Karoubi (ChainComplex C ℕ)).ReflectsIsomorphisms := ⟨fun {X Y} f => by intro -- restating the result in a way that allows induction on the degree n suffices ∀ n : ℕ, IsIso (f.app (op [n])) by haveI : ∀ Δ : SimplexCategoryᵒᵖ, IsIso (f.app Δ) := fun Δ => this Δ.unop.len apply NatIso.isIso_of_isIso_app -- restating the assumption in a more practical form have h₁ := HomologicalComplex.congr_hom (Karoubi.hom_ext_iff.mp (IsIso.hom_inv_id (N₁.map f))) have h₂ := HomologicalComplex.congr_hom (Karoubi.hom_ext_iff.mp (IsIso.inv_hom_id (N₁.map f))) have h₃ := fun n => Karoubi.HomologicalComplex.p_comm_f_assoc (inv (N₁.map f)) n (f.app (op [n])) simp only [N₁_map_f, Karoubi.comp_f, HomologicalComplex.comp_f, AlternatingFaceMapComplex.map_f, N₁_obj_p, Karoubi.id_eq, assoc] at h₁ h₂ h₃ -- we have to construct an inverse to f in degree n, by induction on n intro n induction' n with n hn -- degree 0 · use (inv (N₁.map f)).f.f 0 have h₁₀ := h₁ 0 have h₂₀ := h₂ 0 dsimp at h₁₀ h₂₀ simp only [id_comp, comp_id] at h₁₀ h₂₀ tauto · haveI := hn use φ { a := PInfty.f (n + 1) ≫ (inv (N₁.map f)).f.f (n + 1) b := fun i => inv (f.app (op [n])) ≫ X.σ i } simp only [MorphComponents.id, ← id_φ, ← preComp_φ, preComp, ← postComp_φ, postComp, PInfty_f_naturality_assoc, IsIso.hom_inv_id_assoc, assoc, IsIso.inv_hom_id_assoc, SimplicialObject.σ_naturality, h₁, h₂, h₃, and_self]⟩
Mathlib/AlgebraicTopology/DoldKan/NReflectsIso.lean
68
92
theorem compatibility_N₂_N₁_karoubi : N₂ ⋙ (karoubiChainComplexEquivalence C ℕ).functor = karoubiFunctorCategoryEmbedding SimplexCategoryᵒᵖ C ⋙ N₁ ⋙ (karoubiChainComplexEquivalence (Karoubi C) ℕ).functor ⋙ Functor.mapHomologicalComplex (KaroubiKaroubi.equivalence C).inverse _ := by
refine CategoryTheory.Functor.ext (fun P => ?_) fun P Q f => ?_ · refine HomologicalComplex.ext ?_ ?_ · ext n · rfl · dsimp simp only [karoubi_PInfty_f, comp_id, PInfty_f_naturality, id_comp, eqToHom_refl] · rintro _ n (rfl : n + 1 = _) ext have h := (AlternatingFaceMapComplex.map P.p).comm (n + 1) n dsimp [N₂, karoubiChainComplexEquivalence, KaroubiHomologicalComplexEquivalence.Functor.obj] at h ⊢ simp only [assoc, Karoubi.eqToHom_f, eqToHom_refl, comp_id, karoubi_alternatingFaceMapComplex_d, karoubi_PInfty_f, ← HomologicalComplex.Hom.comm_assoc, ← h, app_idem_assoc] · ext n dsimp [KaroubiKaroubi.inverse, Functor.mapHomologicalComplex] simp only [karoubi_PInfty_f, HomologicalComplex.eqToHom_f, Karoubi.eqToHom_f, assoc, comp_id, PInfty_f_naturality, app_p_comp, karoubiChainComplexEquivalence_functor_obj_X_p, N₂_obj_p_f, eqToHom_refl, PInfty_f_naturality_assoc, app_comp_p, PInfty_f_idem_assoc]
import Mathlib.Data.List.Lattice import Mathlib.Data.List.Range import Mathlib.Data.Bool.Basic #align_import data.list.intervals from "leanprover-community/mathlib"@"7b78d1776212a91ecc94cf601f83bdcc46b04213" open Nat namespace List def Ico (n m : ℕ) : List ℕ := range' n (m - n) #align list.Ico List.Ico namespace Ico theorem zero_bot (n : ℕ) : Ico 0 n = range n := by rw [Ico, Nat.sub_zero, range_eq_range'] #align list.Ico.zero_bot List.Ico.zero_bot @[simp] theorem length (n m : ℕ) : length (Ico n m) = m - n := by dsimp [Ico] simp [length_range', autoParam] #align list.Ico.length List.Ico.length theorem pairwise_lt (n m : ℕ) : Pairwise (· < ·) (Ico n m) := by dsimp [Ico] simp [pairwise_lt_range', autoParam] #align list.Ico.pairwise_lt List.Ico.pairwise_lt theorem nodup (n m : ℕ) : Nodup (Ico n m) := by dsimp [Ico] simp [nodup_range', autoParam] #align list.Ico.nodup List.Ico.nodup @[simp] theorem mem {n m l : ℕ} : l ∈ Ico n m ↔ n ≤ l ∧ l < m := by suffices n ≤ l ∧ l < n + (m - n) ↔ n ≤ l ∧ l < m by simp [Ico, this] rcases le_total n m with hnm | hmn · rw [Nat.add_sub_cancel' hnm] · rw [Nat.sub_eq_zero_iff_le.mpr hmn, Nat.add_zero] exact and_congr_right fun hnl => Iff.intro (fun hln => (not_le_of_gt hln hnl).elim) fun hlm => lt_of_lt_of_le hlm hmn #align list.Ico.mem List.Ico.mem theorem eq_nil_of_le {n m : ℕ} (h : m ≤ n) : Ico n m = [] := by simp [Ico, Nat.sub_eq_zero_iff_le.mpr h] #align list.Ico.eq_nil_of_le List.Ico.eq_nil_of_le theorem map_add (n m k : ℕ) : (Ico n m).map (k + ·) = Ico (n + k) (m + k) := by rw [Ico, Ico, map_add_range', Nat.add_sub_add_right m k, Nat.add_comm n k] #align list.Ico.map_add List.Ico.map_add theorem map_sub (n m k : ℕ) (h₁ : k ≤ n) : ((Ico n m).map fun x => x - k) = Ico (n - k) (m - k) := by rw [Ico, Ico, Nat.sub_sub_sub_cancel_right h₁, map_sub_range' _ _ _ h₁] #align list.Ico.map_sub List.Ico.map_sub @[simp] theorem self_empty {n : ℕ} : Ico n n = [] := eq_nil_of_le (le_refl n) #align list.Ico.self_empty List.Ico.self_empty @[simp] theorem eq_empty_iff {n m : ℕ} : Ico n m = [] ↔ m ≤ n := Iff.intro (fun h => Nat.sub_eq_zero_iff_le.mp <| by rw [← length, h, List.length]) eq_nil_of_le #align list.Ico.eq_empty_iff List.Ico.eq_empty_iff theorem append_consecutive {n m l : ℕ} (hnm : n ≤ m) (hml : m ≤ l) : Ico n m ++ Ico m l = Ico n l := by dsimp only [Ico] convert range'_append n (m-n) (l-m) 1 using 2 · rw [Nat.one_mul, Nat.add_sub_cancel' hnm] · rw [Nat.sub_add_sub_cancel hml hnm] #align list.Ico.append_consecutive List.Ico.append_consecutive @[simp]
Mathlib/Data/List/Intervals.lean
104
110
theorem inter_consecutive (n m l : ℕ) : Ico n m ∩ Ico m l = [] := by
apply eq_nil_iff_forall_not_mem.2 intro a simp only [and_imp, not_and, not_lt, List.mem_inter_iff, List.Ico.mem] intro _ h₂ h₃ exfalso exact not_lt_of_ge h₃ h₂
import Mathlib.Algebra.Polynomial.AlgebraMap import Mathlib.Algebra.Polynomial.BigOperators import Mathlib.Algebra.Polynomial.Degree.Lemmas import Mathlib.Algebra.Polynomial.Div #align_import data.polynomial.ring_division from "leanprover-community/mathlib"@"8efcf8022aac8e01df8d302dcebdbc25d6a886c8" noncomputable section open Polynomial open Finset namespace Polynomial universe u v w z variable {R : Type u} {S : Type v} {T : Type w} {a b : R} {n : ℕ} section NoZeroDivisors variable [Semiring R] [NoZeroDivisors R] {p q : R[X]} instance : NoZeroDivisors R[X] where eq_zero_or_eq_zero_of_mul_eq_zero h := by rw [← leadingCoeff_eq_zero, ← leadingCoeff_eq_zero] refine eq_zero_or_eq_zero_of_mul_eq_zero ?_ rw [← leadingCoeff_zero, ← leadingCoeff_mul, h] theorem natDegree_mul (hp : p ≠ 0) (hq : q ≠ 0) : (p*q).natDegree = p.natDegree + q.natDegree := by rw [← Nat.cast_inj (R := WithBot ℕ), ← degree_eq_natDegree (mul_ne_zero hp hq), Nat.cast_add, ← degree_eq_natDegree hp, ← degree_eq_natDegree hq, degree_mul] #align polynomial.nat_degree_mul Polynomial.natDegree_mul theorem trailingDegree_mul : (p * q).trailingDegree = p.trailingDegree + q.trailingDegree := by by_cases hp : p = 0 · rw [hp, zero_mul, trailingDegree_zero, top_add] by_cases hq : q = 0 · rw [hq, mul_zero, trailingDegree_zero, add_top] · rw [trailingDegree_eq_natTrailingDegree hp, trailingDegree_eq_natTrailingDegree hq, trailingDegree_eq_natTrailingDegree (mul_ne_zero hp hq), natTrailingDegree_mul hp hq] apply WithTop.coe_add #align polynomial.trailing_degree_mul Polynomial.trailingDegree_mul @[simp] theorem natDegree_pow (p : R[X]) (n : ℕ) : natDegree (p ^ n) = n * natDegree p := by classical obtain rfl | hp := eq_or_ne p 0 · obtain rfl | hn := eq_or_ne n 0 <;> simp [*] exact natDegree_pow' $ by rw [← leadingCoeff_pow, Ne, leadingCoeff_eq_zero]; exact pow_ne_zero _ hp #align polynomial.nat_degree_pow Polynomial.natDegree_pow theorem degree_le_mul_left (p : R[X]) (hq : q ≠ 0) : degree p ≤ degree (p * q) := by classical exact if hp : p = 0 then by simp only [hp, zero_mul, le_refl] else by rw [degree_mul, degree_eq_natDegree hp, degree_eq_natDegree hq]; exact WithBot.coe_le_coe.2 (Nat.le_add_right _ _) #align polynomial.degree_le_mul_left Polynomial.degree_le_mul_left theorem natDegree_le_of_dvd {p q : R[X]} (h1 : p ∣ q) (h2 : q ≠ 0) : p.natDegree ≤ q.natDegree := by rcases h1 with ⟨q, rfl⟩; rw [mul_ne_zero_iff] at h2 rw [natDegree_mul h2.1 h2.2]; exact Nat.le_add_right _ _ #align polynomial.nat_degree_le_of_dvd Polynomial.natDegree_le_of_dvd theorem degree_le_of_dvd {p q : R[X]} (h1 : p ∣ q) (h2 : q ≠ 0) : degree p ≤ degree q := by rcases h1 with ⟨q, rfl⟩; rw [mul_ne_zero_iff] at h2 exact degree_le_mul_left p h2.2 #align polynomial.degree_le_of_dvd Polynomial.degree_le_of_dvd theorem eq_zero_of_dvd_of_degree_lt {p q : R[X]} (h₁ : p ∣ q) (h₂ : degree q < degree p) : q = 0 := by by_contra hc exact (lt_iff_not_ge _ _).mp h₂ (degree_le_of_dvd h₁ hc) #align polynomial.eq_zero_of_dvd_of_degree_lt Polynomial.eq_zero_of_dvd_of_degree_lt theorem eq_zero_of_dvd_of_natDegree_lt {p q : R[X]} (h₁ : p ∣ q) (h₂ : natDegree q < natDegree p) : q = 0 := by by_contra hc exact (lt_iff_not_ge _ _).mp h₂ (natDegree_le_of_dvd h₁ hc) #align polynomial.eq_zero_of_dvd_of_nat_degree_lt Polynomial.eq_zero_of_dvd_of_natDegree_lt theorem not_dvd_of_degree_lt {p q : R[X]} (h0 : q ≠ 0) (hl : q.degree < p.degree) : ¬p ∣ q := by by_contra hcontra exact h0 (eq_zero_of_dvd_of_degree_lt hcontra hl) #align polynomial.not_dvd_of_degree_lt Polynomial.not_dvd_of_degree_lt theorem not_dvd_of_natDegree_lt {p q : R[X]} (h0 : q ≠ 0) (hl : q.natDegree < p.natDegree) : ¬p ∣ q := by by_contra hcontra exact h0 (eq_zero_of_dvd_of_natDegree_lt hcontra hl) #align polynomial.not_dvd_of_nat_degree_lt Polynomial.not_dvd_of_natDegree_lt
Mathlib/Algebra/Polynomial/RingDivision.lean
190
195
theorem natDegree_sub_eq_of_prod_eq {p₁ p₂ q₁ q₂ : R[X]} (hp₁ : p₁ ≠ 0) (hq₁ : q₁ ≠ 0) (hp₂ : p₂ ≠ 0) (hq₂ : q₂ ≠ 0) (h_eq : p₁ * q₂ = p₂ * q₁) : (p₁.natDegree : ℤ) - q₁.natDegree = (p₂.natDegree : ℤ) - q₂.natDegree := by
rw [sub_eq_sub_iff_add_eq_add] norm_cast rw [← natDegree_mul hp₁ hq₂, ← natDegree_mul hp₂ hq₁, h_eq]
import Mathlib.CategoryTheory.Limits.Shapes.Pullbacks import Mathlib.CategoryTheory.Limits.Shapes.BinaryProducts import Mathlib.CategoryTheory.Limits.Preserves.Shapes.Pullbacks #align_import category_theory.limits.constructions.epi_mono from "leanprover-community/mathlib"@"f7baecbb54bd0f24f228576f97b1752fc3c9b318" universe v₁ v₂ u₁ u₂ namespace CategoryTheory open Category Limits variable {C : Type u₁} {D : Type u₂} [Category.{v₁} C] [Category.{v₂} D] variable (F : C ⥤ D) theorem preserves_mono_of_preservesLimit {X Y : C} (f : X ⟶ Y) [PreservesLimit (cospan f f) F] [Mono f] : Mono (F.map f) := by have := isLimitPullbackConeMapOfIsLimit F _ (PullbackCone.isLimitMkIdId f) simp_rw [F.map_id] at this apply PullbackCone.mono_of_isLimitMkIdId _ this #align category_theory.preserves_mono_of_preserves_limit CategoryTheory.preserves_mono_of_preservesLimit instance (priority := 100) preservesMonomorphisms_of_preservesLimitsOfShape [PreservesLimitsOfShape WalkingCospan F] : F.PreservesMonomorphisms where preserves f _ := preserves_mono_of_preservesLimit F f #align category_theory.preserves_monomorphisms_of_preserves_limits_of_shape CategoryTheory.preservesMonomorphisms_of_preservesLimitsOfShape
Mathlib/CategoryTheory/Limits/Constructions/EpiMono.lean
45
49
theorem reflects_mono_of_reflectsLimit {X Y : C} (f : X ⟶ Y) [ReflectsLimit (cospan f f) F] [Mono (F.map f)] : Mono f := by
have := PullbackCone.isLimitMkIdId (F.map f) simp_rw [← F.map_id] at this apply PullbackCone.mono_of_isLimitMkIdId _ (isLimitOfIsLimitPullbackConeMap F _ this)
import Mathlib.Analysis.Quaternion import Mathlib.Analysis.NormedSpace.Exponential import Mathlib.Analysis.SpecialFunctions.Trigonometric.Series #align_import analysis.normed_space.quaternion_exponential from "leanprover-community/mathlib"@"f0c8bf9245297a541f468be517f1bde6195105e9" open scoped Quaternion Nat open NormedSpace namespace Quaternion @[simp, norm_cast] theorem exp_coe (r : ℝ) : exp ℝ (r : ℍ[ℝ]) = ↑(exp ℝ r) := (map_exp ℝ (algebraMap ℝ ℍ[ℝ]) (continuous_algebraMap _ _) _).symm #align quaternion.exp_coe Quaternion.exp_coe theorem expSeries_even_of_imaginary {q : Quaternion ℝ} (hq : q.re = 0) (n : ℕ) : expSeries ℝ (Quaternion ℝ) (2 * n) (fun _ => q) = ↑((-1 : ℝ) ^ n * ‖q‖ ^ (2 * n) / (2 * n)!) := by rw [expSeries_apply_eq] have hq2 : q ^ 2 = -normSq q := sq_eq_neg_normSq.mpr hq letI k : ℝ := ↑(2 * n)! calc k⁻¹ • q ^ (2 * n) = k⁻¹ • (-normSq q) ^ n := by rw [pow_mul, hq2] _ = k⁻¹ • ↑((-1 : ℝ) ^ n * ‖q‖ ^ (2 * n)) := ?_ _ = ↑((-1 : ℝ) ^ n * ‖q‖ ^ (2 * n) / k) := ?_ · congr 1 rw [neg_pow, normSq_eq_norm_mul_self, pow_mul, sq] push_cast rfl · rw [← coe_mul_eq_smul, div_eq_mul_inv] norm_cast ring_nf theorem expSeries_odd_of_imaginary {q : Quaternion ℝ} (hq : q.re = 0) (n : ℕ) : expSeries ℝ (Quaternion ℝ) (2 * n + 1) (fun _ => q) = (((-1 : ℝ) ^ n * ‖q‖ ^ (2 * n + 1) / (2 * n + 1)!) / ‖q‖) • q := by rw [expSeries_apply_eq] obtain rfl | hq0 := eq_or_ne q 0 · simp have hq2 : q ^ 2 = -normSq q := sq_eq_neg_normSq.mpr hq have hqn := norm_ne_zero_iff.mpr hq0 let k : ℝ := ↑(2 * n + 1)! calc k⁻¹ • q ^ (2 * n + 1) = k⁻¹ • ((-normSq q) ^ n * q) := by rw [pow_succ, pow_mul, hq2] _ = k⁻¹ • ((-1 : ℝ) ^ n * ‖q‖ ^ (2 * n)) • q := ?_ _ = ((-1 : ℝ) ^ n * ‖q‖ ^ (2 * n + 1) / k / ‖q‖) • q := ?_ · congr 1 rw [neg_pow, normSq_eq_norm_mul_self, pow_mul, sq, ← coe_mul_eq_smul] norm_cast · rw [smul_smul] congr 1 simp_rw [pow_succ, mul_div_assoc, div_div_cancel_left' hqn] ring theorem hasSum_expSeries_of_imaginary {q : Quaternion ℝ} (hq : q.re = 0) {c s : ℝ} (hc : HasSum (fun n => (-1 : ℝ) ^ n * ‖q‖ ^ (2 * n) / (2 * n)!) c) (hs : HasSum (fun n => (-1 : ℝ) ^ n * ‖q‖ ^ (2 * n + 1) / (2 * n + 1)!) s) : HasSum (fun n => expSeries ℝ (Quaternion ℝ) n fun _ => q) (↑c + (s / ‖q‖) • q) := by replace hc := hasSum_coe.mpr hc replace hs := (hs.div_const ‖q‖).smul_const q refine HasSum.even_add_odd ?_ ?_ · convert hc using 1 ext n : 1 rw [expSeries_even_of_imaginary hq] · convert hs using 1 ext n : 1 rw [expSeries_odd_of_imaginary hq] #align quaternion.has_sum_exp_series_of_imaginary Quaternion.hasSum_expSeries_of_imaginary theorem exp_of_re_eq_zero (q : Quaternion ℝ) (hq : q.re = 0) : exp ℝ q = ↑(Real.cos ‖q‖) + (Real.sin ‖q‖ / ‖q‖) • q := by rw [exp_eq_tsum] refine HasSum.tsum_eq ?_ simp_rw [← expSeries_apply_eq] exact hasSum_expSeries_of_imaginary hq (Real.hasSum_cos _) (Real.hasSum_sin _) #align quaternion.exp_of_re_eq_zero Quaternion.exp_of_re_eq_zero theorem exp_eq (q : Quaternion ℝ) : exp ℝ q = exp ℝ q.re • (↑(Real.cos ‖q.im‖) + (Real.sin ‖q.im‖ / ‖q.im‖) • q.im) := by rw [← exp_of_re_eq_zero q.im q.im_re, ← coe_mul_eq_smul, ← exp_coe, ← exp_add_of_commute, re_add_im] exact Algebra.commutes q.re (_ : ℍ[ℝ]) #align quaternion.exp_eq Quaternion.exp_eq theorem re_exp (q : ℍ[ℝ]) : (exp ℝ q).re = exp ℝ q.re * Real.cos ‖q - q.re‖ := by simp [exp_eq] #align quaternion.re_exp Quaternion.re_exp
Mathlib/Analysis/NormedSpace/QuaternionExponential.lean
117
118
theorem im_exp (q : ℍ[ℝ]) : (exp ℝ q).im = (exp ℝ q.re * (Real.sin ‖q.im‖ / ‖q.im‖)) • q.im := by
simp [exp_eq, smul_smul]
import Mathlib.Data.Fin.Fin2 import Mathlib.Data.PFun import Mathlib.Data.Vector3 import Mathlib.NumberTheory.PellMatiyasevic #align_import number_theory.dioph from "leanprover-community/mathlib"@"a66d07e27d5b5b8ac1147cacfe353478e5c14002" open Fin2 Function Nat Sum local infixr:67 " ::ₒ " => Option.elim' local infixr:65 " ⊗ " => Sum.elim universe u section Polynomials variable {α β γ : Type*} inductive IsPoly : ((α → ℕ) → ℤ) → Prop | proj : ∀ i, IsPoly fun x : α → ℕ => x i | const : ∀ n : ℤ, IsPoly fun _ : α → ℕ => n | sub : ∀ {f g : (α → ℕ) → ℤ}, IsPoly f → IsPoly g → IsPoly fun x => f x - g x | mul : ∀ {f g : (α → ℕ) → ℤ}, IsPoly f → IsPoly g → IsPoly fun x => f x * g x #align is_poly IsPoly theorem IsPoly.neg {f : (α → ℕ) → ℤ} : IsPoly f → IsPoly (-f) := by rw [← zero_sub]; exact (IsPoly.const 0).sub #align is_poly.neg IsPoly.neg
Mathlib/NumberTheory/Dioph.lean
89
90
theorem IsPoly.add {f g : (α → ℕ) → ℤ} (hf : IsPoly f) (hg : IsPoly g) : IsPoly (f + g) := by
rw [← sub_neg_eq_add]; exact hf.sub hg.neg
import Mathlib.CategoryTheory.Limits.Shapes.Pullbacks import Mathlib.CategoryTheory.Limits.Shapes.ZeroMorphisms import Mathlib.CategoryTheory.Limits.Constructions.BinaryProducts #align_import category_theory.limits.constructions.zero_objects from "leanprover-community/mathlib"@"52a270e2ea4e342c2587c106f8be904524214a4b" noncomputable section open CategoryTheory variable {C : Type*} [Category C] namespace CategoryTheory.Limits variable [HasZeroObject C] [HasZeroMorphisms C] open ZeroObject def binaryFanZeroLeft (X : C) : BinaryFan (0 : C) X := BinaryFan.mk 0 (𝟙 X) #align category_theory.limits.binary_fan_zero_left CategoryTheory.Limits.binaryFanZeroLeft def binaryFanZeroLeftIsLimit (X : C) : IsLimit (binaryFanZeroLeft X) := BinaryFan.isLimitMk (fun s => BinaryFan.snd s) (by aesop_cat) (by aesop_cat) (fun s m _ h₂ => by simpa using h₂) #align category_theory.limits.binary_fan_zero_left_is_limit CategoryTheory.Limits.binaryFanZeroLeftIsLimit instance hasBinaryProduct_zero_left (X : C) : HasBinaryProduct (0 : C) X := HasLimit.mk ⟨_, binaryFanZeroLeftIsLimit X⟩ #align category_theory.limits.has_binary_product_zero_left CategoryTheory.Limits.hasBinaryProduct_zero_left def zeroProdIso (X : C) : (0 : C) ⨯ X ≅ X := limit.isoLimitCone ⟨_, binaryFanZeroLeftIsLimit X⟩ #align category_theory.limits.zero_prod_iso CategoryTheory.Limits.zeroProdIso @[simp] theorem zeroProdIso_hom (X : C) : (zeroProdIso X).hom = prod.snd := rfl #align category_theory.limits.zero_prod_iso_hom CategoryTheory.Limits.zeroProdIso_hom @[simp]
Mathlib/CategoryTheory/Limits/Constructions/ZeroObjects.lean
58
60
theorem zeroProdIso_inv_snd (X : C) : (zeroProdIso X).inv ≫ prod.snd = 𝟙 X := by
dsimp [zeroProdIso, binaryFanZeroLeft] simp
import Mathlib.Data.Multiset.Nodup #align_import data.multiset.sum from "leanprover-community/mathlib"@"9003f28797c0664a49e4179487267c494477d853" open Sum namespace Multiset variable {α β : Type*} (s : Multiset α) (t : Multiset β) def disjSum : Multiset (Sum α β) := s.map inl + t.map inr #align multiset.disj_sum Multiset.disjSum @[simp] theorem zero_disjSum : (0 : Multiset α).disjSum t = t.map inr := zero_add _ #align multiset.zero_disj_sum Multiset.zero_disjSum @[simp] theorem disjSum_zero : s.disjSum (0 : Multiset β) = s.map inl := add_zero _ #align multiset.disj_sum_zero Multiset.disjSum_zero @[simp] theorem card_disjSum : Multiset.card (s.disjSum t) = Multiset.card s + Multiset.card t := by rw [disjSum, card_add, card_map, card_map] #align multiset.card_disj_sum Multiset.card_disjSum variable {s t} {s₁ s₂ : Multiset α} {t₁ t₂ : Multiset β} {a : α} {b : β} {x : Sum α β}
Mathlib/Data/Multiset/Sum.lean
50
51
theorem mem_disjSum : x ∈ s.disjSum t ↔ (∃ a, a ∈ s ∧ inl a = x) ∨ ∃ b, b ∈ t ∧ inr b = x := by
simp_rw [disjSum, mem_add, mem_map]
import Mathlib.Algebra.DirectSum.Finsupp import Mathlib.LinearAlgebra.Finsupp import Mathlib.LinearAlgebra.DirectSum.TensorProduct #align_import linear_algebra.direct_sum.finsupp from "leanprover-community/mathlib"@"9b9d125b7be0930f564a68f1d73ace10cf46064d" noncomputable section open DirectSum TensorProduct open Set LinearMap Submodule variable (R S M N ι κ : Type*) [CommSemiring R] [AddCommMonoid M] [Module R M] [AddCommMonoid N] [Module R N] [Semiring S] [Algebra R S] [Module S M] [IsScalarTower R S M] open scoped Classical in def finsuppTensorFinsupp : (ι →₀ M) ⊗[R] (κ →₀ N) ≃ₗ[S] ι × κ →₀ M ⊗[R] N := TensorProduct.AlgebraTensorModule.congr (finsuppLEquivDirectSum S M ι) (finsuppLEquivDirectSum R N κ) ≪≫ₗ ((TensorProduct.directSum R S (fun _ : ι => M) fun _ : κ => N) ≪≫ₗ (finsuppLEquivDirectSum S (M ⊗[R] N) (ι × κ)).symm) #align finsupp_tensor_finsupp finsuppTensorFinsupp @[simp] theorem finsuppTensorFinsupp_single (i : ι) (m : M) (k : κ) (n : N) : finsuppTensorFinsupp R S M N ι κ (Finsupp.single i m ⊗ₜ Finsupp.single k n) = Finsupp.single (i, k) (m ⊗ₜ n) := by simp [finsuppTensorFinsupp] #align finsupp_tensor_finsupp_single finsuppTensorFinsupp_single @[simp] theorem finsuppTensorFinsupp_apply (f : ι →₀ M) (g : κ →₀ N) (i : ι) (k : κ) : finsuppTensorFinsupp R S M N ι κ (f ⊗ₜ g) (i, k) = f i ⊗ₜ g k := by apply Finsupp.induction_linear f · simp · intro f₁ f₂ hf₁ hf₂ simp [add_tmul, hf₁, hf₂] intro i' m apply Finsupp.induction_linear g · simp · intro g₁ g₂ hg₁ hg₂ simp [tmul_add, hg₁, hg₂] intro k' n classical simp_rw [finsuppTensorFinsupp_single, Finsupp.single_apply, Prod.mk.inj_iff, ite_and] split_ifs <;> simp #align finsupp_tensor_finsupp_apply finsuppTensorFinsupp_apply @[simp] theorem finsuppTensorFinsupp_symm_single (i : ι × κ) (m : M) (n : N) : (finsuppTensorFinsupp R S M N ι κ).symm (Finsupp.single i (m ⊗ₜ n)) = Finsupp.single i.1 m ⊗ₜ Finsupp.single i.2 n := Prod.casesOn i fun _ _ => (LinearEquiv.symm_apply_eq _).2 (finsuppTensorFinsupp_single _ _ _ _ _ _ _ _ _ _).symm #align finsupp_tensor_finsupp_symm_single finsuppTensorFinsupp_symm_single def finsuppTensorFinsuppLid : (ι →₀ R) ⊗[R] (κ →₀ N) ≃ₗ[R] ι × κ →₀ N := finsuppTensorFinsupp R R R N ι κ ≪≫ₗ Finsupp.lcongr (Equiv.refl _) (TensorProduct.lid R N) @[simp] theorem finsuppTensorFinsuppLid_apply_apply (f : ι →₀ R) (g : κ →₀ N) (a : ι) (b : κ) : finsuppTensorFinsuppLid R N ι κ (f ⊗ₜ[R] g) (a, b) = f a • g b := by simp [finsuppTensorFinsuppLid] @[simp] theorem finsuppTensorFinsuppLid_single_tmul_single (a : ι) (b : κ) (r : R) (n : N) : finsuppTensorFinsuppLid R N ι κ (Finsupp.single a r ⊗ₜ[R] Finsupp.single b n) = Finsupp.single (a, b) (r • n) := by simp [finsuppTensorFinsuppLid] @[simp] theorem finsuppTensorFinsuppLid_symm_single_smul (i : ι × κ) (r : R) (n : N) : (finsuppTensorFinsuppLid R N ι κ).symm (Finsupp.single i (r • n)) = Finsupp.single i.1 r ⊗ₜ Finsupp.single i.2 n := Prod.casesOn i fun _ _ => (LinearEquiv.symm_apply_eq _).2 (finsuppTensorFinsuppLid_single_tmul_single ..).symm def finsuppTensorFinsuppRid : (ι →₀ M) ⊗[R] (κ →₀ R) ≃ₗ[R] ι × κ →₀ M := finsuppTensorFinsupp R R M R ι κ ≪≫ₗ Finsupp.lcongr (Equiv.refl _) (TensorProduct.rid R M) @[simp]
Mathlib/LinearAlgebra/DirectSum/Finsupp.lean
315
317
theorem finsuppTensorFinsuppRid_apply_apply (f : ι →₀ M) (g : κ →₀ R) (a : ι) (b : κ) : finsuppTensorFinsuppRid R M ι κ (f ⊗ₜ[R] g) (a, b) = g b • f a := by
simp [finsuppTensorFinsuppRid]
import Mathlib.Analysis.SpecialFunctions.Trigonometric.Bounds #align_import data.real.pi.bounds from "leanprover-community/mathlib"@"402f8982dddc1864bd703da2d6e2ee304a866973" -- Porting note: needed to add a lot of type ascriptions for lean to interpret numbers as reals. open scoped Real namespace Real theorem pi_gt_sqrtTwoAddSeries (n : ℕ) : (2 : ℝ) ^ (n + 1) * √(2 - sqrtTwoAddSeries 0 n) < π := by have : √(2 - sqrtTwoAddSeries 0 n) / (2 : ℝ) * (2 : ℝ) ^ (n + 2) < π := by rw [← lt_div_iff, ← sin_pi_over_two_pow_succ] focus apply sin_lt apply div_pos pi_pos all_goals apply pow_pos; norm_num apply lt_of_le_of_lt (le_of_eq _) this rw [pow_succ' _ (n + 1), ← mul_assoc, div_mul_cancel₀, mul_comm]; norm_num #align real.pi_gt_sqrt_two_add_series Real.pi_gt_sqrtTwoAddSeries theorem pi_lt_sqrtTwoAddSeries (n : ℕ) : π < (2 : ℝ) ^ (n + 1) * √(2 - sqrtTwoAddSeries 0 n) + 1 / (4 : ℝ) ^ n := by have : π < (√(2 - sqrtTwoAddSeries 0 n) / (2 : ℝ) + (1 : ℝ) / ((2 : ℝ) ^ n) ^ 3 / 4) * (2 : ℝ) ^ (n + 2) := by rw [← div_lt_iff (by norm_num), ← sin_pi_over_two_pow_succ] refine lt_of_lt_of_le (lt_add_of_sub_right_lt (sin_gt_sub_cube ?_ ?_)) ?_ · apply div_pos pi_pos; apply pow_pos; norm_num · rw [div_le_iff'] · refine le_trans pi_le_four ?_ simp only [show (4 : ℝ) = (2 : ℝ) ^ 2 by norm_num, mul_one] apply pow_le_pow_right (by norm_num) apply le_add_of_nonneg_left; apply Nat.zero_le · apply pow_pos; norm_num apply add_le_add_left; rw [div_le_div_right (by norm_num)] rw [le_div_iff (by norm_num), ← mul_pow] refine le_trans ?_ (le_of_eq (one_pow 3)); apply pow_le_pow_left · apply le_of_lt; apply mul_pos · apply div_pos pi_pos; apply pow_pos; norm_num · apply pow_pos; norm_num · rw [← le_div_iff (by norm_num)] refine le_trans ((div_le_div_right ?_).mpr pi_le_four) ?_ · apply pow_pos; norm_num · simp only [pow_succ', ← div_div, one_div] -- Porting note: removed `convert le_rfl` norm_num apply lt_of_lt_of_le this (le_of_eq _); rw [add_mul]; congr 1 · ring simp only [show (4 : ℝ) = 2 ^ 2 by norm_num, ← pow_mul, div_div, ← pow_add] rw [one_div, one_div, inv_mul_eq_iff_eq_mul₀, eq_comm, mul_inv_eq_iff_eq_mul₀, ← pow_add] · rw [add_assoc, Nat.mul_succ, add_comm, add_comm n, add_assoc, mul_comm n] all_goals norm_num #align real.pi_lt_sqrt_two_add_series Real.pi_lt_sqrtTwoAddSeries
Mathlib/Data/Real/Pi/Bounds.lean
77
82
theorem pi_lower_bound_start (n : ℕ) {a} (h : sqrtTwoAddSeries ((0 : ℕ) / (1 : ℕ)) n ≤ (2 : ℝ) - (a / (2 : ℝ) ^ (n + 1)) ^ 2) : a < π := by
refine lt_of_le_of_lt ?_ (pi_gt_sqrtTwoAddSeries n); rw [mul_comm] refine (div_le_iff (pow_pos (by norm_num) _ : (0 : ℝ) < _)).mp (le_sqrt_of_sq_le ?_) rwa [le_sub_comm, show (0 : ℝ) = (0 : ℕ) / (1 : ℕ) by rw [Nat.cast_zero, zero_div]]
import Mathlib.Algebra.Regular.Basic import Mathlib.LinearAlgebra.Matrix.MvPolynomial import Mathlib.LinearAlgebra.Matrix.Polynomial import Mathlib.RingTheory.Polynomial.Basic #align_import linear_algebra.matrix.adjugate from "leanprover-community/mathlib"@"a99f85220eaf38f14f94e04699943e185a5e1d1a" namespace Matrix universe u v w variable {m : Type u} {n : Type v} {α : Type w} variable [DecidableEq n] [Fintype n] [DecidableEq m] [Fintype m] [CommRing α] open Matrix Polynomial Equiv Equiv.Perm Finset section Cramer variable (A : Matrix n n α) (b : n → α) def cramerMap (i : n) : α := (A.updateColumn i b).det #align matrix.cramer_map Matrix.cramerMap theorem cramerMap_is_linear (i : n) : IsLinearMap α fun b => cramerMap A b i := { map_add := det_updateColumn_add _ _ map_smul := det_updateColumn_smul _ _ } #align matrix.cramer_map_is_linear Matrix.cramerMap_is_linear theorem cramer_is_linear : IsLinearMap α (cramerMap A) := by constructor <;> intros <;> ext i · apply (cramerMap_is_linear A i).1 · apply (cramerMap_is_linear A i).2 #align matrix.cramer_is_linear Matrix.cramer_is_linear def cramer (A : Matrix n n α) : (n → α) →ₗ[α] (n → α) := IsLinearMap.mk' (cramerMap A) (cramer_is_linear A) #align matrix.cramer Matrix.cramer theorem cramer_apply (i : n) : cramer A b i = (A.updateColumn i b).det := rfl #align matrix.cramer_apply Matrix.cramer_apply
Mathlib/LinearAlgebra/Matrix/Adjugate.lean
102
103
theorem cramer_transpose_apply (i : n) : cramer Aᵀ b i = (A.updateRow i b).det := by
rw [cramer_apply, updateColumn_transpose, det_transpose]
import Mathlib.NumberTheory.DirichletCharacter.Bounds import Mathlib.NumberTheory.EulerProduct.Basic import Mathlib.NumberTheory.LSeries.Basic import Mathlib.NumberTheory.LSeries.RiemannZeta open Complex variable {s : ℂ} noncomputable def riemannZetaSummandHom (hs : s ≠ 0) : ℕ →*₀ ℂ where toFun n := (n : ℂ) ^ (-s) map_zero' := by simp [hs] map_one' := by simp map_mul' m n := by simpa only [Nat.cast_mul, ofReal_natCast] using mul_cpow_ofReal_nonneg m.cast_nonneg n.cast_nonneg _ noncomputable def dirichletSummandHom {n : ℕ} (χ : DirichletCharacter ℂ n) (hs : s ≠ 0) : ℕ →*₀ ℂ where toFun n := χ n * (n : ℂ) ^ (-s) map_zero' := by simp [hs] map_one' := by simp map_mul' m n := by simp_rw [← ofReal_natCast] simpa only [Nat.cast_mul, IsUnit.mul_iff, not_and, map_mul, ofReal_mul, mul_cpow_ofReal_nonneg m.cast_nonneg n.cast_nonneg _] using mul_mul_mul_comm .. lemma summable_riemannZetaSummand (hs : 1 < s.re) : Summable (fun n ↦ ‖riemannZetaSummandHom (ne_zero_of_one_lt_re hs) n‖) := by simp only [riemannZetaSummandHom, MonoidWithZeroHom.coe_mk, ZeroHom.coe_mk] convert Real.summable_nat_rpow_inv.mpr hs with n rw [← ofReal_natCast, Complex.norm_eq_abs, abs_cpow_eq_rpow_re_of_nonneg (Nat.cast_nonneg n) <| re_neg_ne_zero_of_one_lt_re hs, neg_re, Real.rpow_neg <| Nat.cast_nonneg n] lemma tsum_riemannZetaSummand (hs : 1 < s.re) : ∑' (n : ℕ), riemannZetaSummandHom (ne_zero_of_one_lt_re hs) n = riemannZeta s := by have hsum := summable_riemannZetaSummand hs rw [zeta_eq_tsum_one_div_nat_add_one_cpow hs, tsum_eq_zero_add hsum.of_norm, map_zero, zero_add] simp only [riemannZetaSummandHom, cpow_neg, MonoidWithZeroHom.coe_mk, ZeroHom.coe_mk, Nat.cast_add, Nat.cast_one, one_div] lemma summable_dirichletSummand {N : ℕ} (χ : DirichletCharacter ℂ N) (hs : 1 < s.re) : Summable (fun n ↦ ‖dirichletSummandHom χ (ne_zero_of_one_lt_re hs) n‖) := by simp only [dirichletSummandHom, MonoidWithZeroHom.coe_mk, ZeroHom.coe_mk, norm_mul] exact (summable_riemannZetaSummand hs).of_nonneg_of_le (fun _ ↦ by positivity) (fun n ↦ mul_le_of_le_one_left (norm_nonneg _) <| χ.norm_le_one n) open scoped LSeries.notation in lemma tsum_dirichletSummand {N : ℕ} (χ : DirichletCharacter ℂ N) (hs : 1 < s.re) : ∑' (n : ℕ), dirichletSummandHom χ (ne_zero_of_one_lt_re hs) n = L ↗χ s := by simp only [LSeries, LSeries.term, dirichletSummandHom] refine tsum_congr (fun n ↦ ?_) rcases eq_or_ne n 0 with rfl | hn · simp only [map_zero, ↓reduceIte] · simp only [cpow_neg, MonoidWithZeroHom.coe_mk, ZeroHom.coe_mk, hn, ↓reduceIte, Field.div_eq_mul_inv] open Filter Nat Topology EulerProduct
Mathlib/NumberTheory/EulerProduct/DirichletLSeries.lean
91
94
theorem riemannZeta_eulerProduct_hasProd (hs : 1 < s.re) : HasProd (fun p : Primes ↦ (1 - (p : ℂ) ^ (-s))⁻¹) (riemannZeta s) := by
rw [← tsum_riemannZetaSummand hs] apply eulerProduct_completely_multiplicative_hasProd <| summable_riemannZetaSummand hs
import Mathlib.NumberTheory.Cyclotomic.Embeddings import Mathlib.NumberTheory.Cyclotomic.Rat import Mathlib.NumberTheory.NumberField.Units.DirichletTheorem open NumberField Units InfinitePlace nonZeroDivisors Polynomial namespace IsCyclotomicExtension.Rat.Three variable {K : Type*} [Field K] [NumberField K] [IsCyclotomicExtension {3} ℚ K] variable {ζ : K} (hζ : IsPrimitiveRoot ζ ↑(3 : ℕ+)) (u : (𝓞 K)ˣ) local notation3 "η" => (IsPrimitiveRoot.isUnit (hζ.toInteger_isPrimitiveRoot) (by decide)).unit local notation3 "λ" => (η : 𝓞 K) - 1 -- Here `List` is more convenient than `Finset`, even if further from the informal statement. -- For example, `fin_cases` below does not work with a `Finset`.
Mathlib/NumberTheory/Cyclotomic/Three.lean
41
68
theorem Units.mem : u ∈ [1, -1, η, -η, η ^ 2, -η ^ 2] := by
have hrank : rank K = 0 := by dsimp only [rank] rw [card_eq_nrRealPlaces_add_nrComplexPlaces, nrRealPlaces_eq_zero (n := 3) K (by decide), zero_add, nrComplexPlaces_eq_totient_div_two (n := 3)] rfl obtain ⟨⟨x, e⟩, hxu, -⟩ := exist_unique_eq_mul_prod _ u replace hxu : u = x := by rw [← mul_one x.1, hxu] apply congr_arg rw [← Finset.prod_empty] congr rw [Finset.univ_eq_empty_iff, hrank] infer_instance obtain ⟨n, hnpos, hn⟩ := isOfFinOrder_iff_pow_eq_one.1 <| (CommGroup.mem_torsion _ _).1 x.2 replace hn : (↑u : K) ^ ((⟨n, hnpos⟩ : ℕ+) : ℕ) = 1 := by rw [← map_pow] convert map_one (algebraMap (𝓞 K) K) rw_mod_cast [hxu, hn] simp obtain ⟨r, hr3, hru⟩ := hζ.exists_pow_or_neg_mul_pow_of_isOfFinOrder (by decide) (isOfFinOrder_iff_pow_eq_one.2 ⟨n, hnpos, hn⟩) replace hr : r ∈ Finset.Ico 0 3 := Finset.mem_Ico.2 ⟨by simp, hr3⟩ replace hru : ↑u = η ^ r ∨ ↑u = -η ^ r := by rcases hru with (h | h) · left; ext; exact h · right; ext; exact h fin_cases hr <;> rcases hru with (h | h) <;> simp [h]