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import Mathlib.Topology.Sheaves.Sheaf import Mathlib.CategoryTheory.Sites.Limits import Mathlib.CategoryTheory.Limits.FunctorCategory #align_import topology.sheaves.limits from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a" noncomputable section universe v u open CategoryTheory open CategoryTheory.Limits variable {C : Type u} [Category.{v} C] {J : Type v} [SmallCategory J] namespace TopCat instance [HasLimits C] (X : TopCat) : HasLimits (Presheaf C X) := Limits.functorCategoryHasLimitsOfSize.{v, v} instance [HasColimits C] (X : TopCat) : HasColimitsOfSize.{v} (Presheaf C X) := Limits.functorCategoryHasColimitsOfSize instance [HasLimits C] (X : TopCat) : CreatesLimits (Sheaf.forget C X) := Sheaf.createsLimits.{u, v, v} instance [HasLimits C] (X : TopCat) : HasLimitsOfSize.{v} (Sheaf.{v} C X) := hasLimits_of_hasLimits_createsLimits (Sheaf.forget C X)
Mathlib/Topology/Sheaves/Limits.lean
41
49
theorem isSheaf_of_isLimit [HasLimits C] {X : TopCat} (F : J ⥤ Presheaf.{v} C X) (H : ∀ j, (F.obj j).IsSheaf) {c : Cone F} (hc : IsLimit c) : c.pt.IsSheaf := by
let F' : J ⥤ Sheaf C X := { obj := fun j => ⟨F.obj j, H j⟩ map := fun f => ⟨F.map f⟩ } let e : F' ⋙ Sheaf.forget C X ≅ F := NatIso.ofComponents fun _ => Iso.refl _ exact Presheaf.isSheaf_of_iso ((isLimitOfPreserves (Sheaf.forget C X) (limit.isLimit F')).conePointsIsoOfNatIso hc e) (limit F').2
import Mathlib.Data.ENNReal.Inv #align_import data.real.ennreal from "leanprover-community/mathlib"@"c14c8fcde993801fca8946b0d80131a1a81d1520" open Set NNReal ENNReal namespace ENNReal section iInf variable {ι : Sort*} {f g : ι → ℝ≥0∞} variable {a b c d : ℝ≥0∞} {r p q : ℝ≥0} theorem toNNReal_iInf (hf : ∀ i, f i ≠ ∞) : (iInf f).toNNReal = ⨅ i, (f i).toNNReal := by cases isEmpty_or_nonempty ι · rw [iInf_of_empty, top_toNNReal, NNReal.iInf_empty] · lift f to ι → ℝ≥0 using hf simp_rw [← coe_iInf, toNNReal_coe] #align ennreal.to_nnreal_infi ENNReal.toNNReal_iInf theorem toNNReal_sInf (s : Set ℝ≥0∞) (hs : ∀ r ∈ s, r ≠ ∞) : (sInf s).toNNReal = sInf (ENNReal.toNNReal '' s) := by have hf : ∀ i, ((↑) : s → ℝ≥0∞) i ≠ ∞ := fun ⟨r, rs⟩ => hs r rs -- Porting note: `← sInf_image'` had to be replaced by `← image_eq_range` as the lemmas are used -- in a different order. simpa only [← sInf_range, ← image_eq_range, Subtype.range_coe_subtype] using (toNNReal_iInf hf) #align ennreal.to_nnreal_Inf ENNReal.toNNReal_sInf theorem toNNReal_iSup (hf : ∀ i, f i ≠ ∞) : (iSup f).toNNReal = ⨆ i, (f i).toNNReal := by lift f to ι → ℝ≥0 using hf simp_rw [toNNReal_coe] by_cases h : BddAbove (range f) · rw [← coe_iSup h, toNNReal_coe] · rw [NNReal.iSup_of_not_bddAbove h, iSup_coe_eq_top.2 h, top_toNNReal] #align ennreal.to_nnreal_supr ENNReal.toNNReal_iSup
Mathlib/Data/ENNReal/Real.lean
564
569
theorem toNNReal_sSup (s : Set ℝ≥0∞) (hs : ∀ r ∈ s, r ≠ ∞) : (sSup s).toNNReal = sSup (ENNReal.toNNReal '' s) := by
have hf : ∀ i, ((↑) : s → ℝ≥0∞) i ≠ ∞ := fun ⟨r, rs⟩ => hs r rs -- Porting note: `← sSup_image'` had to be replaced by `← image_eq_range` as the lemmas are used -- in a different order. simpa only [← sSup_range, ← image_eq_range, Subtype.range_coe_subtype] using (toNNReal_iSup hf)
import Mathlib.Algebra.GCDMonoid.Basic import Mathlib.Algebra.EuclideanDomain.Basic import Mathlib.RingTheory.Ideal.Basic import Mathlib.RingTheory.PrincipalIdealDomain #align_import ring_theory.euclidean_domain from "leanprover-community/mathlib"@"bf9bbbcf0c1c1ead18280b0d010e417b10abb1b6" section open EuclideanDomain Set Ideal section GCDMonoid variable {R : Type*} [EuclideanDomain R] [GCDMonoid R] {p q : R} theorem gcd_ne_zero_of_left (hp : p ≠ 0) : GCDMonoid.gcd p q ≠ 0 := fun h => hp <| eq_zero_of_zero_dvd (h ▸ gcd_dvd_left p q) #align gcd_ne_zero_of_left gcd_ne_zero_of_left theorem gcd_ne_zero_of_right (hp : q ≠ 0) : GCDMonoid.gcd p q ≠ 0 := fun h => hp <| eq_zero_of_zero_dvd (h ▸ gcd_dvd_right p q) #align gcd_ne_zero_of_right gcd_ne_zero_of_right theorem left_div_gcd_ne_zero {p q : R} (hp : p ≠ 0) : p / GCDMonoid.gcd p q ≠ 0 := by obtain ⟨r, hr⟩ := GCDMonoid.gcd_dvd_left p q obtain ⟨pq0, r0⟩ : GCDMonoid.gcd p q ≠ 0 ∧ r ≠ 0 := mul_ne_zero_iff.mp (hr ▸ hp) nth_rw 1 [hr] rw [mul_comm, mul_div_cancel_right₀ _ pq0] exact r0 #align left_div_gcd_ne_zero left_div_gcd_ne_zero
Mathlib/RingTheory/EuclideanDomain.lean
50
55
theorem right_div_gcd_ne_zero {p q : R} (hq : q ≠ 0) : q / GCDMonoid.gcd p q ≠ 0 := by
obtain ⟨r, hr⟩ := GCDMonoid.gcd_dvd_right p q obtain ⟨pq0, r0⟩ : GCDMonoid.gcd p q ≠ 0 ∧ r ≠ 0 := mul_ne_zero_iff.mp (hr ▸ hq) nth_rw 1 [hr] rw [mul_comm, mul_div_cancel_right₀ _ pq0] exact r0
import Mathlib.Algebra.Algebra.Defs import Mathlib.Algebra.CharP.ExpChar import Mathlib.FieldTheory.Separable #align_import field_theory.separable_degree from "leanprover-community/mathlib"@"d11893b411025250c8e61ff2f12ccbd7ee35ab15" noncomputable section namespace Polynomial open scoped Classical open Polynomial section CommSemiring variable {F : Type*} [CommSemiring F] (q : ℕ) def IsSeparableContraction (f : F[X]) (g : F[X]) : Prop := g.Separable ∧ ∃ m : ℕ, expand F (q ^ m) g = f #align polynomial.is_separable_contraction Polynomial.IsSeparableContraction def HasSeparableContraction (f : F[X]) : Prop := ∃ g : F[X], IsSeparableContraction q f g #align polynomial.has_separable_contraction Polynomial.HasSeparableContraction variable {q} {f : F[X]} (hf : HasSeparableContraction q f) def HasSeparableContraction.contraction : F[X] := Classical.choose hf #align polynomial.has_separable_contraction.contraction Polynomial.HasSeparableContraction.contraction def HasSeparableContraction.degree : ℕ := hf.contraction.natDegree #align polynomial.has_separable_contraction.degree Polynomial.HasSeparableContraction.degree theorem HasSeparableContraction.isSeparableContraction : IsSeparableContraction q f hf.contraction := Classical.choose_spec hf
Mathlib/RingTheory/Polynomial/SeparableDegree.lean
78
82
theorem IsSeparableContraction.dvd_degree' {g} (hf : IsSeparableContraction q f g) : ∃ m : ℕ, g.natDegree * q ^ m = f.natDegree := by
obtain ⟨m, rfl⟩ := hf.2 use m rw [natDegree_expand]
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 CommRing variable [CommRing R] theorem le_rootMultiplicity_iff {p : R[X]} (p0 : p ≠ 0) {a : R} {n : ℕ} : n ≤ rootMultiplicity a p ↔ (X - C a) ^ n ∣ p := by classical rw [rootMultiplicity_eq_nat_find_of_nonzero p0, @Nat.le_find_iff _ (_)] simp_rw [Classical.not_not] refine ⟨fun h => ?_, fun h m hm => (pow_dvd_pow _ hm).trans h⟩ cases' n with n; · rw [pow_zero] apply one_dvd; · exact h n n.lt_succ_self #align polynomial.le_root_multiplicity_iff Polynomial.le_rootMultiplicity_iff theorem rootMultiplicity_le_iff {p : R[X]} (p0 : p ≠ 0) (a : R) (n : ℕ) : rootMultiplicity a p ≤ n ↔ ¬(X - C a) ^ (n + 1) ∣ p := by rw [← (le_rootMultiplicity_iff p0).not, not_le, Nat.lt_add_one_iff] #align polynomial.root_multiplicity_le_iff Polynomial.rootMultiplicity_le_iff theorem pow_rootMultiplicity_not_dvd {p : R[X]} (p0 : p ≠ 0) (a : R) : ¬(X - C a) ^ (rootMultiplicity a p + 1) ∣ p := by rw [← rootMultiplicity_le_iff p0] #align polynomial.pow_root_multiplicity_not_dvd Polynomial.pow_rootMultiplicity_not_dvd theorem X_sub_C_pow_dvd_iff {p : R[X]} {t : R} {n : ℕ} : (X - C t) ^ n ∣ p ↔ X ^ n ∣ p.comp (X + C t) := by convert (map_dvd_iff <| algEquivAevalXAddC t).symm using 2 simp [C_eq_algebraMap] theorem comp_X_add_C_eq_zero_iff {p : R[X]} (t : R) : p.comp (X + C t) = 0 ↔ p = 0 := AddEquivClass.map_eq_zero_iff (algEquivAevalXAddC t) theorem comp_X_add_C_ne_zero_iff {p : R[X]} (t : R) : p.comp (X + C t) ≠ 0 ↔ p ≠ 0 := Iff.not <| comp_X_add_C_eq_zero_iff t theorem rootMultiplicity_eq_rootMultiplicity {p : R[X]} {t : R} : p.rootMultiplicity t = (p.comp (X + C t)).rootMultiplicity 0 := by classical simp_rw [rootMultiplicity_eq_multiplicity, comp_X_add_C_eq_zero_iff] congr; ext; congr 1 rw [C_0, sub_zero] convert (multiplicity.multiplicity_map_eq <| algEquivAevalXAddC t).symm using 2 simp [C_eq_algebraMap]
Mathlib/Algebra/Polynomial/RingDivision.lean
468
477
theorem rootMultiplicity_eq_natTrailingDegree' {p : R[X]} : p.rootMultiplicity 0 = p.natTrailingDegree := by
by_cases h : p = 0 · simp only [h, rootMultiplicity_zero, natTrailingDegree_zero] refine le_antisymm ?_ ?_ · rw [rootMultiplicity_le_iff h, map_zero, sub_zero, X_pow_dvd_iff, not_forall] exact ⟨p.natTrailingDegree, fun h' ↦ trailingCoeff_nonzero_iff_nonzero.2 h <| h' <| Nat.lt.base _⟩ · rw [le_rootMultiplicity_iff h, map_zero, sub_zero, X_pow_dvd_iff] exact fun _ ↦ coeff_eq_zero_of_lt_natTrailingDegree
import Mathlib.Data.Finsupp.Lex import Mathlib.Data.Finsupp.Multiset import Mathlib.Order.GameAdd #align_import logic.hydra from "leanprover-community/mathlib"@"48085f140e684306f9e7da907cd5932056d1aded" namespace Relation open Multiset Prod variable {α : Type*} def CutExpand (r : α → α → Prop) (s' s : Multiset α) : Prop := ∃ (t : Multiset α) (a : α), (∀ a' ∈ t, r a' a) ∧ s' + {a} = s + t #align relation.cut_expand Relation.CutExpand variable {r : α → α → Prop} theorem cutExpand_le_invImage_lex [DecidableEq α] [IsIrrefl α r] : CutExpand r ≤ InvImage (Finsupp.Lex (rᶜ ⊓ (· ≠ ·)) (· < ·)) toFinsupp := by rintro s t ⟨u, a, hr, he⟩ replace hr := fun a' ↦ mt (hr a') classical refine ⟨a, fun b h ↦ ?_, ?_⟩ <;> simp_rw [toFinsupp_apply] · apply_fun count b at he simpa only [count_add, count_singleton, if_neg h.2, add_zero, count_eq_zero.2 (hr b h.1)] using he · apply_fun count a at he simp only [count_add, count_singleton_self, count_eq_zero.2 (hr _ (irrefl_of r a)), add_zero] at he exact he ▸ Nat.lt_succ_self _ #align relation.cut_expand_le_inv_image_lex Relation.cutExpand_le_invImage_lex theorem cutExpand_singleton {s x} (h : ∀ x' ∈ s, r x' x) : CutExpand r s {x} := ⟨s, x, h, add_comm s _⟩ #align relation.cut_expand_singleton Relation.cutExpand_singleton theorem cutExpand_singleton_singleton {x' x} (h : r x' x) : CutExpand r {x'} {x} := cutExpand_singleton fun a h ↦ by rwa [mem_singleton.1 h] #align relation.cut_expand_singleton_singleton Relation.cutExpand_singleton_singleton theorem cutExpand_add_left {t u} (s) : CutExpand r (s + t) (s + u) ↔ CutExpand r t u := exists₂_congr fun _ _ ↦ and_congr Iff.rfl <| by rw [add_assoc, add_assoc, add_left_cancel_iff] #align relation.cut_expand_add_left Relation.cutExpand_add_left theorem cutExpand_iff [DecidableEq α] [IsIrrefl α r] {s' s : Multiset α} : CutExpand r s' s ↔ ∃ (t : Multiset α) (a : α), (∀ a' ∈ t, r a' a) ∧ a ∈ s ∧ s' = s.erase a + t := by simp_rw [CutExpand, add_singleton_eq_iff] refine exists₂_congr fun t a ↦ ⟨?_, ?_⟩ · rintro ⟨ht, ha, rfl⟩ obtain h | h := mem_add.1 ha exacts [⟨ht, h, erase_add_left_pos t h⟩, (@irrefl α r _ a (ht a h)).elim] · rintro ⟨ht, h, rfl⟩ exact ⟨ht, mem_add.2 (Or.inl h), (erase_add_left_pos t h).symm⟩ #align relation.cut_expand_iff Relation.cutExpand_iff theorem not_cutExpand_zero [IsIrrefl α r] (s) : ¬CutExpand r s 0 := by classical rw [cutExpand_iff] rintro ⟨_, _, _, ⟨⟩, _⟩ #align relation.not_cut_expand_zero Relation.not_cutExpand_zero
Mathlib/Logic/Hydra.lean
109
121
theorem cutExpand_fibration (r : α → α → Prop) : Fibration (GameAdd (CutExpand r) (CutExpand r)) (CutExpand r) fun s ↦ s.1 + s.2 := by
rintro ⟨s₁, s₂⟩ s ⟨t, a, hr, he⟩; dsimp at he ⊢ classical obtain ⟨ha, rfl⟩ := add_singleton_eq_iff.1 he rw [add_assoc, mem_add] at ha obtain h | h := ha · refine ⟨(s₁.erase a + t, s₂), GameAdd.fst ⟨t, a, hr, ?_⟩, ?_⟩ · rw [add_comm, ← add_assoc, singleton_add, cons_erase h] · rw [add_assoc s₁, erase_add_left_pos _ h, add_right_comm, add_assoc] · refine ⟨(s₁, (s₂ + t).erase a), GameAdd.snd ⟨t, a, hr, ?_⟩, ?_⟩ · rw [add_comm, singleton_add, cons_erase h] · rw [add_assoc, erase_add_right_pos _ h]
import Mathlib.Algebra.BigOperators.Fin import Mathlib.Algebra.BigOperators.NatAntidiagonal import Mathlib.Algebra.CharZero.Lemmas import Mathlib.Data.Finset.NatAntidiagonal import Mathlib.Data.Nat.Choose.Central import Mathlib.Data.Tree.Basic import Mathlib.Tactic.FieldSimp import Mathlib.Tactic.GCongr import Mathlib.Tactic.Positivity #align_import combinatorics.catalan from "leanprover-community/mathlib"@"26b40791e4a5772a4e53d0e28e4df092119dc7da" open Finset open Finset.antidiagonal (fst_le snd_le) def catalan : ℕ → ℕ | 0 => 1 | n + 1 => ∑ i : Fin n.succ, catalan i * catalan (n - i) #align catalan catalan @[simp] theorem catalan_zero : catalan 0 = 1 := by rw [catalan] #align catalan_zero catalan_zero theorem catalan_succ (n : ℕ) : catalan (n + 1) = ∑ i : Fin n.succ, catalan i * catalan (n - i) := by rw [catalan] #align catalan_succ catalan_succ theorem catalan_succ' (n : ℕ) : catalan (n + 1) = ∑ ij ∈ antidiagonal n, catalan ij.1 * catalan ij.2 := by rw [catalan_succ, Nat.sum_antidiagonal_eq_sum_range_succ (fun x y => catalan x * catalan y) n, sum_range] #align catalan_succ' catalan_succ' @[simp]
Mathlib/Combinatorics/Enumerative/Catalan.lean
79
79
theorem catalan_one : catalan 1 = 1 := by
simp [catalan_succ]
import Mathlib.Data.Set.Image import Mathlib.Data.List.InsertNth import Mathlib.Init.Data.List.Lemmas #align_import data.list.lemmas from "leanprover-community/mathlib"@"2ec920d35348cb2d13ac0e1a2ad9df0fdf1a76b4" open List variable {α β γ : Type*} namespace List theorem injOn_insertNth_index_of_not_mem (l : List α) (x : α) (hx : x ∉ l) : Set.InjOn (fun k => insertNth k x l) { n | n ≤ l.length } := by induction' l with hd tl IH · intro n hn m hm _ simp only [Set.mem_singleton_iff, Set.setOf_eq_eq_singleton, length] at hn hm simp_all [hn, hm] · intro n hn m hm h simp only [length, Set.mem_setOf_eq] at hn hm simp only [mem_cons, not_or] at hx cases n <;> cases m · rfl · simp [hx.left] at h · simp [Ne.symm hx.left] at h · simp only [true_and_iff, eq_self_iff_true, insertNth_succ_cons] at h rw [Nat.succ_inj'] refine IH hx.right ?_ ?_ (by injection h) · simpa [Nat.succ_le_succ_iff] using hn · simpa [Nat.succ_le_succ_iff] using hm #align list.inj_on_insert_nth_index_of_not_mem List.injOn_insertNth_index_of_not_mem
Mathlib/Data/List/Lemmas.lean
44
52
theorem foldr_range_subset_of_range_subset {f : β → α → α} {g : γ → α → α} (hfg : Set.range f ⊆ Set.range g) (a : α) : Set.range (foldr f a) ⊆ Set.range (foldr g a) := by
rintro _ ⟨l, rfl⟩ induction' l with b l H · exact ⟨[], rfl⟩ · cases' hfg (Set.mem_range_self b) with c hgf cases' H with m hgf' rw [foldr_cons, ← hgf, ← hgf'] exact ⟨c :: m, rfl⟩
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
Mathlib/Data/Num/Prime.lean
44
54
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]
import Mathlib.Topology.Algebra.Module.WeakDual import Mathlib.MeasureTheory.Integral.BoundedContinuousFunction import Mathlib.MeasureTheory.Measure.HasOuterApproxClosed #align_import measure_theory.measure.finite_measure from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982" noncomputable section open MeasureTheory open Set open Filter open BoundedContinuousFunction open scoped Topology ENNReal NNReal BoundedContinuousFunction namespace MeasureTheory namespace FiniteMeasure section FiniteMeasure variable {Ω : Type*} [MeasurableSpace Ω] def _root_.MeasureTheory.FiniteMeasure (Ω : Type*) [MeasurableSpace Ω] : Type _ := { μ : Measure Ω // IsFiniteMeasure μ } #align measure_theory.finite_measure MeasureTheory.FiniteMeasure -- Porting note: as with other subtype synonyms (e.g., `ℝ≥0`, we need a new function for the -- coercion instead of relying on `Subtype.val`. @[coe] def toMeasure : FiniteMeasure Ω → Measure Ω := Subtype.val instance instCoe : Coe (FiniteMeasure Ω) (MeasureTheory.Measure Ω) where coe := toMeasure instance isFiniteMeasure (μ : FiniteMeasure Ω) : IsFiniteMeasure (μ : Measure Ω) := μ.prop #align measure_theory.finite_measure.is_finite_measure MeasureTheory.FiniteMeasure.isFiniteMeasure @[simp] theorem val_eq_toMeasure (ν : FiniteMeasure Ω) : ν.val = (ν : Measure Ω) := rfl #align measure_theory.finite_measure.val_eq_to_measure MeasureTheory.FiniteMeasure.val_eq_toMeasure theorem toMeasure_injective : Function.Injective ((↑) : FiniteMeasure Ω → Measure Ω) := Subtype.coe_injective #align measure_theory.finite_measure.coe_injective MeasureTheory.FiniteMeasure.toMeasure_injective instance instFunLike : FunLike (FiniteMeasure Ω) (Set Ω) ℝ≥0 where coe μ s := ((μ : Measure Ω) s).toNNReal coe_injective' μ ν h := toMeasure_injective $ Measure.ext fun s _ ↦ by simpa [ENNReal.toNNReal_eq_toNNReal_iff, measure_ne_top] using congr_fun h s lemma coeFn_def (μ : FiniteMeasure Ω) : μ = fun s ↦ ((μ : Measure Ω) s).toNNReal := rfl #align measure_theory.finite_measure.coe_fn_eq_to_nnreal_coe_fn_to_measure MeasureTheory.FiniteMeasure.coeFn_def lemma coeFn_mk (μ : Measure Ω) (hμ) : DFunLike.coe (F := FiniteMeasure Ω) ⟨μ, hμ⟩ = fun s ↦ (μ s).toNNReal := rfl @[simp, norm_cast] lemma mk_apply (μ : Measure Ω) (hμ) (s : Set Ω) : DFunLike.coe (F := FiniteMeasure Ω) ⟨μ, hμ⟩ s = (μ s).toNNReal := rfl @[simp] theorem ennreal_coeFn_eq_coeFn_toMeasure (ν : FiniteMeasure Ω) (s : Set Ω) : (ν s : ℝ≥0∞) = (ν : Measure Ω) s := ENNReal.coe_toNNReal (measure_lt_top (↑ν) s).ne #align measure_theory.finite_measure.ennreal_coe_fn_eq_coe_fn_to_measure MeasureTheory.FiniteMeasure.ennreal_coeFn_eq_coeFn_toMeasure theorem apply_mono (μ : FiniteMeasure Ω) {s₁ s₂ : Set Ω} (h : s₁ ⊆ s₂) : μ s₁ ≤ μ s₂ := by change ((μ : Measure Ω) s₁).toNNReal ≤ ((μ : Measure Ω) s₂).toNNReal have key : (μ : Measure Ω) s₁ ≤ (μ : Measure Ω) s₂ := (μ : Measure Ω).mono h apply (ENNReal.toNNReal_le_toNNReal (measure_ne_top _ s₁) (measure_ne_top _ s₂)).mpr key #align measure_theory.finite_measure.apply_mono MeasureTheory.FiniteMeasure.apply_mono def mass (μ : FiniteMeasure Ω) : ℝ≥0 := μ univ #align measure_theory.finite_measure.mass MeasureTheory.FiniteMeasure.mass @[simp] theorem apply_le_mass (μ : FiniteMeasure Ω) (s : Set Ω) : μ s ≤ μ.mass := by simpa using apply_mono μ (subset_univ s) @[simp] theorem ennreal_mass {μ : FiniteMeasure Ω} : (μ.mass : ℝ≥0∞) = (μ : Measure Ω) univ := ennreal_coeFn_eq_coeFn_toMeasure μ Set.univ #align measure_theory.finite_measure.ennreal_mass MeasureTheory.FiniteMeasure.ennreal_mass instance instZero : Zero (FiniteMeasure Ω) where zero := ⟨0, MeasureTheory.isFiniteMeasureZero⟩ #align measure_theory.finite_measure.has_zero MeasureTheory.FiniteMeasure.instZero @[simp, norm_cast] lemma coeFn_zero : ⇑(0 : FiniteMeasure Ω) = 0 := rfl #align measure_theory.finite_measure.coe_fn_zero MeasureTheory.FiniteMeasure.coeFn_zero @[simp] theorem zero_mass : (0 : FiniteMeasure Ω).mass = 0 := rfl #align measure_theory.finite_measure.zero.mass MeasureTheory.FiniteMeasure.zero_mass @[simp] theorem mass_zero_iff (μ : FiniteMeasure Ω) : μ.mass = 0 ↔ μ = 0 := by refine ⟨fun μ_mass => ?_, fun hμ => by simp only [hμ, zero_mass]⟩ apply toMeasure_injective apply Measure.measure_univ_eq_zero.mp rwa [← ennreal_mass, ENNReal.coe_eq_zero] #align measure_theory.finite_measure.mass_zero_iff MeasureTheory.FiniteMeasure.mass_zero_iff
Mathlib/MeasureTheory/Measure/FiniteMeasure.lean
207
209
theorem mass_nonzero_iff (μ : FiniteMeasure Ω) : μ.mass ≠ 0 ↔ μ ≠ 0 := by
rw [not_iff_not] exact FiniteMeasure.mass_zero_iff μ
import Batteries.Classes.Order namespace Batteries.PairingHeapImp inductive Heap (α : Type u) where | nil : Heap α | node (a : α) (child sibling : Heap α) : Heap α deriving Repr def Heap.size : Heap α → Nat | .nil => 0 | .node _ c s => c.size + 1 + s.size def Heap.singleton (a : α) : Heap α := .node a .nil .nil def Heap.isEmpty : Heap α → Bool | .nil => true | _ => false @[specialize] def Heap.merge (le : α → α → Bool) : Heap α → Heap α → Heap α | .nil, .nil => .nil | .nil, .node a₂ c₂ _ => .node a₂ c₂ .nil | .node a₁ c₁ _, .nil => .node a₁ c₁ .nil | .node a₁ c₁ _, .node a₂ c₂ _ => if le a₁ a₂ then .node a₁ (.node a₂ c₂ c₁) .nil else .node a₂ (.node a₁ c₁ c₂) .nil @[specialize] def Heap.combine (le : α → α → Bool) : Heap α → Heap α | h₁@(.node _ _ h₂@(.node _ _ s)) => merge le (merge le h₁ h₂) (s.combine le) | h => h @[inline] def Heap.headD (a : α) : Heap α → α | .nil => a | .node a _ _ => a @[inline] def Heap.head? : Heap α → Option α | .nil => none | .node a _ _ => some a @[inline] def Heap.deleteMin (le : α → α → Bool) : Heap α → Option (α × Heap α) | .nil => none | .node a c _ => (a, combine le c) @[inline] def Heap.tail? (le : α → α → Bool) (h : Heap α) : Option (Heap α) := deleteMin le h |>.map (·.snd) @[inline] def Heap.tail (le : α → α → Bool) (h : Heap α) : Heap α := tail? le h |>.getD .nil inductive Heap.NoSibling : Heap α → Prop | nil : NoSibling .nil | node (a c) : NoSibling (.node a c .nil) instance : Decidable (Heap.NoSibling s) := match s with | .nil => isTrue .nil | .node a c .nil => isTrue (.node a c) | .node _ _ (.node _ _ _) => isFalse nofun theorem Heap.noSibling_merge (le) (s₁ s₂ : Heap α) : (s₁.merge le s₂).NoSibling := by unfold merge (split <;> try split) <;> constructor
.lake/packages/batteries/Batteries/Data/PairingHeap.lean
95
101
theorem Heap.noSibling_combine (le) (s : Heap α) : (s.combine le).NoSibling := by
unfold combine; split · exact noSibling_merge _ _ _ · match s with | nil | node _ _ nil => constructor | node _ _ (node _ _ s) => rename_i h; exact (h _ _ _ _ _ rfl).elim
import Mathlib.MeasureTheory.Constructions.Pi import Mathlib.MeasureTheory.Integral.Lebesgue open scoped Classical ENNReal open Set Function Equiv Finset noncomputable section namespace MeasureTheory section LMarginal variable {δ δ' : Type*} {π : δ → Type*} [∀ x, MeasurableSpace (π x)] variable {μ : ∀ i, Measure (π i)} [∀ i, SigmaFinite (μ i)] [DecidableEq δ] variable {s t : Finset δ} {f g : (∀ i, π i) → ℝ≥0∞} {x y : ∀ i, π i} {i : δ} def lmarginal (μ : ∀ i, Measure (π i)) (s : Finset δ) (f : (∀ i, π i) → ℝ≥0∞) (x : ∀ i, π i) : ℝ≥0∞ := ∫⁻ y : ∀ i : s, π i, f (updateFinset x s y) ∂Measure.pi fun i : s => μ i -- Note: this notation is not a binder. This is more convenient since it returns a function. @[inherit_doc] notation "∫⋯∫⁻_" s ", " f " ∂" μ:70 => lmarginal μ s f @[inherit_doc] notation "∫⋯∫⁻_" s ", " f => lmarginal (fun _ ↦ volume) s f variable (μ) theorem _root_.Measurable.lmarginal (hf : Measurable f) : Measurable (∫⋯∫⁻_s, f ∂μ) := by refine Measurable.lintegral_prod_right ?_ refine hf.comp ?_ rw [measurable_pi_iff]; intro i by_cases hi : i ∈ s · simp [hi, updateFinset] exact measurable_pi_iff.1 measurable_snd _ · simp [hi, updateFinset] exact measurable_pi_iff.1 measurable_fst _ @[simp] theorem lmarginal_empty (f : (∀ i, π i) → ℝ≥0∞) : ∫⋯∫⁻_∅, f ∂μ = f := by ext1 x simp_rw [lmarginal, Measure.pi_of_empty fun i : (∅ : Finset δ) => μ i] apply lintegral_dirac' exact Subsingleton.measurable theorem lmarginal_congr {x y : ∀ i, π i} (f : (∀ i, π i) → ℝ≥0∞) (h : ∀ i ∉ s, x i = y i) : (∫⋯∫⁻_s, f ∂μ) x = (∫⋯∫⁻_s, f ∂μ) y := by dsimp [lmarginal, updateFinset_def]; rcongr; exact h _ ‹_› theorem lmarginal_update_of_mem {i : δ} (hi : i ∈ s) (f : (∀ i, π i) → ℝ≥0∞) (x : ∀ i, π i) (y : π i) : (∫⋯∫⁻_s, f ∂μ) (Function.update x i y) = (∫⋯∫⁻_s, f ∂μ) x := by apply lmarginal_congr intro j hj have : j ≠ i := by rintro rfl; exact hj hi apply update_noteq this theorem lmarginal_union (f : (∀ i, π i) → ℝ≥0∞) (hf : Measurable f) (hst : Disjoint s t) : ∫⋯∫⁻_s ∪ t, f ∂μ = ∫⋯∫⁻_s, ∫⋯∫⁻_t, f ∂μ ∂μ := by ext1 x let e := MeasurableEquiv.piFinsetUnion π hst calc (∫⋯∫⁻_s ∪ t, f ∂μ) x = ∫⁻ (y : (i : ↥(s ∪ t)) → π i), f (updateFinset x (s ∪ t) y) ∂.pi fun i' : ↥(s ∪ t) ↦ μ i' := rfl _ = ∫⁻ (y : ((i : s) → π i) × ((j : t) → π j)), f (updateFinset x (s ∪ t) _) ∂(Measure.pi fun i : s ↦ μ i).prod (.pi fun j : t ↦ μ j) := by rw [measurePreserving_piFinsetUnion hst μ |>.lintegral_map_equiv] _ = ∫⁻ (y : (i : s) → π i), ∫⁻ (z : (j : t) → π j), f (updateFinset x (s ∪ t) (e (y, z))) ∂.pi fun j : t ↦ μ j ∂.pi fun i : s ↦ μ i := by apply lintegral_prod apply Measurable.aemeasurable exact hf.comp <| measurable_updateFinset.comp e.measurable _ = (∫⋯∫⁻_s, ∫⋯∫⁻_t, f ∂μ ∂μ) x := by simp_rw [lmarginal, updateFinset_updateFinset hst] rfl
Mathlib/MeasureTheory/Integral/Marginal.lean
137
139
theorem lmarginal_union' (f : (∀ i, π i) → ℝ≥0∞) (hf : Measurable f) {s t : Finset δ} (hst : Disjoint s t) : ∫⋯∫⁻_s ∪ t, f ∂μ = ∫⋯∫⁻_t, ∫⋯∫⁻_s, f ∂μ ∂μ := by
rw [Finset.union_comm, lmarginal_union μ f hf hst.symm]
import Mathlib.Topology.Separation open Topology Filter Set TopologicalSpace section Basic variable {α : Type*} [TopologicalSpace α] {C : Set α}
Mathlib/Topology/Perfect.lean
62
68
theorem AccPt.nhds_inter {x : α} {U : Set α} (h_acc : AccPt x (𝓟 C)) (hU : U ∈ 𝓝 x) : AccPt x (𝓟 (U ∩ C)) := by
have : 𝓝[≠] x ≤ 𝓟 U := by rw [le_principal_iff] exact mem_nhdsWithin_of_mem_nhds hU rw [AccPt, ← inf_principal, ← inf_assoc, inf_of_le_left this] exact h_acc
import Mathlib.FieldTheory.Galois #align_import field_theory.polynomial_galois_group from "leanprover-community/mathlib"@"e3f4be1fcb5376c4948d7f095bec45350bfb9d1a" noncomputable section open scoped Polynomial open FiniteDimensional namespace Polynomial variable {F : Type*} [Field F] (p q : F[X]) (E : Type*) [Field E] [Algebra F E] def Gal := p.SplittingField ≃ₐ[F] p.SplittingField -- Porting note(https://github.com/leanprover-community/mathlib4/issues/5020): -- deriving Group, Fintype #align polynomial.gal Polynomial.Gal namespace Gal instance instGroup : Group (Gal p) := inferInstanceAs (Group (p.SplittingField ≃ₐ[F] p.SplittingField)) instance instFintype : Fintype (Gal p) := inferInstanceAs (Fintype (p.SplittingField ≃ₐ[F] p.SplittingField)) instance : CoeFun p.Gal fun _ => p.SplittingField → p.SplittingField := -- Porting note: was AlgEquiv.hasCoeToFun inferInstanceAs (CoeFun (p.SplittingField ≃ₐ[F] p.SplittingField) _) instance applyMulSemiringAction : MulSemiringAction p.Gal p.SplittingField := AlgEquiv.applyMulSemiringAction #align polynomial.gal.apply_mul_semiring_action Polynomial.Gal.applyMulSemiringAction @[ext] theorem ext {σ τ : p.Gal} (h : ∀ x ∈ p.rootSet p.SplittingField, σ x = τ x) : σ = τ := by refine AlgEquiv.ext fun x => (AlgHom.mem_equalizer σ.toAlgHom τ.toAlgHom x).mp ((SetLike.ext_iff.mp ?_ x).mpr Algebra.mem_top) rwa [eq_top_iff, ← SplittingField.adjoin_rootSet, Algebra.adjoin_le_iff] #align polynomial.gal.ext Polynomial.Gal.ext def uniqueGalOfSplits (h : p.Splits (RingHom.id F)) : Unique p.Gal where default := 1 uniq f := AlgEquiv.ext fun x => by obtain ⟨y, rfl⟩ := Algebra.mem_bot.mp ((SetLike.ext_iff.mp ((IsSplittingField.splits_iff _ p).mp h) x).mp Algebra.mem_top) rw [AlgEquiv.commutes, AlgEquiv.commutes] #align polynomial.gal.unique_gal_of_splits Polynomial.Gal.uniqueGalOfSplits instance [h : Fact (p.Splits (RingHom.id F))] : Unique p.Gal := uniqueGalOfSplits _ h.1 instance uniqueGalZero : Unique (0 : F[X]).Gal := uniqueGalOfSplits _ (splits_zero _) #align polynomial.gal.unique_gal_zero Polynomial.Gal.uniqueGalZero instance uniqueGalOne : Unique (1 : F[X]).Gal := uniqueGalOfSplits _ (splits_one _) #align polynomial.gal.unique_gal_one Polynomial.Gal.uniqueGalOne instance uniqueGalC (x : F) : Unique (C x).Gal := uniqueGalOfSplits _ (splits_C _ _) set_option linter.uppercaseLean3 false in #align polynomial.gal.unique_gal_C Polynomial.Gal.uniqueGalC instance uniqueGalX : Unique (X : F[X]).Gal := uniqueGalOfSplits _ (splits_X _) set_option linter.uppercaseLean3 false in #align polynomial.gal.unique_gal_X Polynomial.Gal.uniqueGalX instance uniqueGalXSubC (x : F) : Unique (X - C x).Gal := uniqueGalOfSplits _ (splits_X_sub_C _) set_option linter.uppercaseLean3 false in #align polynomial.gal.unique_gal_X_sub_C Polynomial.Gal.uniqueGalXSubC instance uniqueGalXPow (n : ℕ) : Unique (X ^ n : F[X]).Gal := uniqueGalOfSplits _ (splits_X_pow _ _) set_option linter.uppercaseLean3 false in #align polynomial.gal.unique_gal_X_pow Polynomial.Gal.uniqueGalXPow instance [h : Fact (p.Splits (algebraMap F E))] : Algebra p.SplittingField E := (IsSplittingField.lift p.SplittingField p h.1).toRingHom.toAlgebra instance [h : Fact (p.Splits (algebraMap F E))] : IsScalarTower F p.SplittingField E := IsScalarTower.of_algebraMap_eq fun x => ((IsSplittingField.lift p.SplittingField p h.1).commutes x).symm -- The `Algebra p.SplittingField E` instance above behaves badly when -- `E := p.SplittingField`, since it may result in a unification problem -- `IsSplittingField.lift.toRingHom.toAlgebra =?= Algebra.id`, -- which takes an extremely long time to resolve, causing timeouts. -- Since we don't really care about this definition, marking it as irreducible -- causes that unification to error out early. def restrict [Fact (p.Splits (algebraMap F E))] : (E ≃ₐ[F] E) →* p.Gal := AlgEquiv.restrictNormalHom p.SplittingField #align polynomial.gal.restrict Polynomial.Gal.restrict theorem restrict_surjective [Fact (p.Splits (algebraMap F E))] [Normal F E] : Function.Surjective (restrict p E) := AlgEquiv.restrictNormalHom_surjective E #align polynomial.gal.restrict_surjective Polynomial.Gal.restrict_surjective section RootsAction def mapRoots [Fact (p.Splits (algebraMap F E))] : rootSet p p.SplittingField → rootSet p E := Set.MapsTo.restrict (IsScalarTower.toAlgHom F p.SplittingField E) _ _ <| rootSet_mapsTo _ #align polynomial.gal.map_roots Polynomial.Gal.mapRoots
Mathlib/FieldTheory/PolynomialGaloisGroup.lean
155
168
theorem mapRoots_bijective [h : Fact (p.Splits (algebraMap F E))] : Function.Bijective (mapRoots p E) := by
constructor · exact fun _ _ h => Subtype.ext (RingHom.injective _ (Subtype.ext_iff.mp h)) · intro y -- this is just an equality of two different ways to write the roots of `p` as an `E`-polynomial have key := roots_map (IsScalarTower.toAlgHom F p.SplittingField E : p.SplittingField →+* E) ((splits_id_iff_splits _).mpr (IsSplittingField.splits p.SplittingField p)) rw [map_map, AlgHom.comp_algebraMap] at key have hy := Subtype.mem y simp only [rootSet, Finset.mem_coe, Multiset.mem_toFinset, key, Multiset.mem_map] at hy rcases hy with ⟨x, hx1, hx2⟩ exact ⟨⟨x, (@Multiset.mem_toFinset _ (Classical.decEq _) _ _).mpr hx1⟩, Subtype.ext hx2⟩
import Mathlib.NumberTheory.Cyclotomic.PrimitiveRoots import Mathlib.NumberTheory.NumberField.Discriminant #align_import number_theory.cyclotomic.discriminant from "leanprover-community/mathlib"@"3e068ece210655b7b9a9477c3aff38a492400aa1" universe u v open Algebra Polynomial Nat IsPrimitiveRoot PowerBasis open scoped Polynomial Cyclotomic namespace IsPrimitiveRoot variable {n : ℕ+} {K : Type u} [Field K] [CharZero K] {ζ : K} variable [ce : IsCyclotomicExtension {n} ℚ K]
Mathlib/NumberTheory/Cyclotomic/Discriminant.lean
37
48
theorem discr_zeta_eq_discr_zeta_sub_one (hζ : IsPrimitiveRoot ζ n) : discr ℚ (hζ.powerBasis ℚ).basis = discr ℚ (hζ.subOnePowerBasis ℚ).basis := by
haveI : NumberField K := @NumberField.mk _ _ _ (IsCyclotomicExtension.finiteDimensional {n} ℚ K) have H₁ : (aeval (hζ.powerBasis ℚ).gen) (X - 1 : ℤ[X]) = (hζ.subOnePowerBasis ℚ).gen := by simp have H₂ : (aeval (hζ.subOnePowerBasis ℚ).gen) (X + 1 : ℤ[X]) = (hζ.powerBasis ℚ).gen := by simp refine discr_eq_discr_of_toMatrix_coeff_isIntegral _ (fun i j => toMatrix_isIntegral H₁ ?_ ?_ _ _) fun i j => toMatrix_isIntegral H₂ ?_ ?_ _ _ · exact hζ.isIntegral n.pos · refine minpoly.isIntegrallyClosed_eq_field_fractions' (K := ℚ) (hζ.isIntegral n.pos) · exact (hζ.isIntegral n.pos).sub isIntegral_one · refine minpoly.isIntegrallyClosed_eq_field_fractions' (K := ℚ) ?_ exact (hζ.isIntegral n.pos).sub isIntegral_one
import Mathlib.Analysis.InnerProductSpace.Projection import Mathlib.Analysis.NormedSpace.PiLp import Mathlib.LinearAlgebra.FiniteDimensional import Mathlib.LinearAlgebra.UnitaryGroup #align_import analysis.inner_product_space.pi_L2 from "leanprover-community/mathlib"@"13bce9a6b6c44f6b4c91ac1c1d2a816e2533d395" set_option linter.uppercaseLean3 false open Real Set Filter RCLike Submodule Function Uniformity Topology NNReal ENNReal ComplexConjugate DirectSum noncomputable section variable {ι ι' 𝕜 : Type*} [RCLike 𝕜] variable {E : Type*} [NormedAddCommGroup E] [InnerProductSpace 𝕜 E] variable {E' : Type*} [NormedAddCommGroup E'] [InnerProductSpace 𝕜 E'] variable {F : Type*} [NormedAddCommGroup F] [InnerProductSpace ℝ F] variable {F' : Type*} [NormedAddCommGroup F'] [InnerProductSpace ℝ F'] local notation "⟪" x ", " y "⟫" => @inner 𝕜 _ _ x y instance PiLp.innerProductSpace {ι : Type*} [Fintype ι] (f : ι → Type*) [∀ i, NormedAddCommGroup (f i)] [∀ i, InnerProductSpace 𝕜 (f i)] : InnerProductSpace 𝕜 (PiLp 2 f) where inner x y := ∑ i, inner (x i) (y i) norm_sq_eq_inner x := by simp only [PiLp.norm_sq_eq_of_L2, map_sum, ← norm_sq_eq_inner, one_div] conj_symm := by intro x y unfold inner rw [map_sum] apply Finset.sum_congr rfl rintro z - apply inner_conj_symm add_left x y z := show (∑ i, inner (x i + y i) (z i)) = (∑ i, inner (x i) (z i)) + ∑ i, inner (y i) (z i) by simp only [inner_add_left, Finset.sum_add_distrib] smul_left x y r := show (∑ i : ι, inner (r • x i) (y i)) = conj r * ∑ i, inner (x i) (y i) by simp only [Finset.mul_sum, inner_smul_left] #align pi_Lp.inner_product_space PiLp.innerProductSpace @[simp] theorem PiLp.inner_apply {ι : Type*} [Fintype ι] {f : ι → Type*} [∀ i, NormedAddCommGroup (f i)] [∀ i, InnerProductSpace 𝕜 (f i)] (x y : PiLp 2 f) : ⟪x, y⟫ = ∑ i, ⟪x i, y i⟫ := rfl #align pi_Lp.inner_apply PiLp.inner_apply abbrev EuclideanSpace (𝕜 : Type*) (n : Type*) : Type _ := PiLp 2 fun _ : n => 𝕜 #align euclidean_space EuclideanSpace theorem EuclideanSpace.nnnorm_eq {𝕜 : Type*} [RCLike 𝕜] {n : Type*} [Fintype n] (x : EuclideanSpace 𝕜 n) : ‖x‖₊ = NNReal.sqrt (∑ i, ‖x i‖₊ ^ 2) := PiLp.nnnorm_eq_of_L2 x #align euclidean_space.nnnorm_eq EuclideanSpace.nnnorm_eq theorem EuclideanSpace.norm_eq {𝕜 : Type*} [RCLike 𝕜] {n : Type*} [Fintype n] (x : EuclideanSpace 𝕜 n) : ‖x‖ = √(∑ i, ‖x i‖ ^ 2) := by simpa only [Real.coe_sqrt, NNReal.coe_sum] using congr_arg ((↑) : ℝ≥0 → ℝ) x.nnnorm_eq #align euclidean_space.norm_eq EuclideanSpace.norm_eq theorem EuclideanSpace.dist_eq {𝕜 : Type*} [RCLike 𝕜] {n : Type*} [Fintype n] (x y : EuclideanSpace 𝕜 n) : dist x y = √(∑ i, dist (x i) (y i) ^ 2) := PiLp.dist_eq_of_L2 x y #align euclidean_space.dist_eq EuclideanSpace.dist_eq theorem EuclideanSpace.nndist_eq {𝕜 : Type*} [RCLike 𝕜] {n : Type*} [Fintype n] (x y : EuclideanSpace 𝕜 n) : nndist x y = NNReal.sqrt (∑ i, nndist (x i) (y i) ^ 2) := PiLp.nndist_eq_of_L2 x y #align euclidean_space.nndist_eq EuclideanSpace.nndist_eq theorem EuclideanSpace.edist_eq {𝕜 : Type*} [RCLike 𝕜] {n : Type*} [Fintype n] (x y : EuclideanSpace 𝕜 n) : edist x y = (∑ i, edist (x i) (y i) ^ 2) ^ (1 / 2 : ℝ) := PiLp.edist_eq_of_L2 x y #align euclidean_space.edist_eq EuclideanSpace.edist_eq theorem EuclideanSpace.ball_zero_eq {n : Type*} [Fintype n] (r : ℝ) (hr : 0 ≤ r) : Metric.ball (0 : EuclideanSpace ℝ n) r = {x | ∑ i, x i ^ 2 < r ^ 2} := by ext x have : (0 : ℝ) ≤ ∑ i, x i ^ 2 := Finset.sum_nonneg fun _ _ => sq_nonneg _ simp_rw [mem_setOf, mem_ball_zero_iff, norm_eq, norm_eq_abs, sq_abs, sqrt_lt this hr] theorem EuclideanSpace.closedBall_zero_eq {n : Type*} [Fintype n] (r : ℝ) (hr : 0 ≤ r) : Metric.closedBall (0 : EuclideanSpace ℝ n) r = {x | ∑ i, x i ^ 2 ≤ r ^ 2} := by ext simp_rw [mem_setOf, mem_closedBall_zero_iff, norm_eq, norm_eq_abs, sq_abs, sqrt_le_left hr]
Mathlib/Analysis/InnerProductSpace/PiL2.lean
145
150
theorem EuclideanSpace.sphere_zero_eq {n : Type*} [Fintype n] (r : ℝ) (hr : 0 ≤ r) : Metric.sphere (0 : EuclideanSpace ℝ n) r = {x | ∑ i, x i ^ 2 = r ^ 2} := by
ext x have : (0 : ℝ) ≤ ∑ i, x i ^ 2 := Finset.sum_nonneg fun _ _ => sq_nonneg _ simp_rw [mem_setOf, mem_sphere_zero_iff_norm, norm_eq, norm_eq_abs, sq_abs, Real.sqrt_eq_iff_sq_eq this hr, eq_comm]
import Mathlib.Probability.ProbabilityMassFunction.Basic import Mathlib.Probability.ProbabilityMassFunction.Constructions import Mathlib.MeasureTheory.Integral.Bochner namespace PMF open MeasureTheory ENNReal TopologicalSpace section General variable {α : Type*} [MeasurableSpace α] [MeasurableSingletonClass α] variable {E : Type*} [NormedAddCommGroup E] [NormedSpace ℝ E] [CompleteSpace E]
Mathlib/Probability/ProbabilityMassFunction/Integrals.lean
28
41
theorem integral_eq_tsum (p : PMF α) (f : α → E) (hf : Integrable f p.toMeasure) : ∫ a, f a ∂(p.toMeasure) = ∑' a, (p a).toReal • f a := calc _ = ∫ a in p.support, f a ∂(p.toMeasure) := by
rw [restrict_toMeasure_support p] _ = ∑' (a : support p), (p.toMeasure {a.val}).toReal • f a := by apply integral_countable f p.support_countable rwa [restrict_toMeasure_support p] _ = ∑' (a : support p), (p a).toReal • f a := by congr with x; congr 2 apply PMF.toMeasure_apply_singleton p x (MeasurableSet.singleton _) _ = ∑' a, (p a).toReal • f a := tsum_subtype_eq_of_support_subset <| by calc (fun a ↦ (p a).toReal • f a).support ⊆ (fun a ↦ (p a).toReal).support := Function.support_smul_subset_left _ _ _ ⊆ support p := fun x h1 h2 => h1 (by simp [h2])
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
Mathlib/Data/List/Intervals.lean
95
100
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]
import Mathlib.Algebra.Polynomial.BigOperators import Mathlib.Algebra.Polynomial.Derivative import Mathlib.Data.Nat.Choose.Cast import Mathlib.Data.Nat.Choose.Vandermonde import Mathlib.Tactic.FieldSimp #align_import data.polynomial.hasse_deriv from "leanprover-community/mathlib"@"a148d797a1094ab554ad4183a4ad6f130358ef64" noncomputable section namespace Polynomial open Nat Polynomial open Function variable {R : Type*} [Semiring R] (k : ℕ) (f : R[X]) def hasseDeriv (k : ℕ) : R[X] →ₗ[R] R[X] := lsum fun i => monomial (i - k) ∘ₗ DistribMulAction.toLinearMap R R (i.choose k) #align polynomial.hasse_deriv Polynomial.hasseDeriv theorem hasseDeriv_apply : hasseDeriv k f = f.sum fun i r => monomial (i - k) (↑(i.choose k) * r) := by dsimp [hasseDeriv] congr; ext; congr apply nsmul_eq_mul #align polynomial.hasse_deriv_apply Polynomial.hasseDeriv_apply theorem hasseDeriv_coeff (n : ℕ) : (hasseDeriv k f).coeff n = (n + k).choose k * f.coeff (n + k) := by rw [hasseDeriv_apply, coeff_sum, sum_def, Finset.sum_eq_single (n + k), coeff_monomial] · simp only [if_true, add_tsub_cancel_right, eq_self_iff_true] · intro i _hi hink rw [coeff_monomial] by_cases hik : i < k · simp only [Nat.choose_eq_zero_of_lt hik, ite_self, Nat.cast_zero, zero_mul] · push_neg at hik rw [if_neg] contrapose! hink exact (tsub_eq_iff_eq_add_of_le hik).mp hink · intro h simp only [not_mem_support_iff.mp h, monomial_zero_right, mul_zero, coeff_zero] #align polynomial.hasse_deriv_coeff Polynomial.hasseDeriv_coeff theorem hasseDeriv_zero' : hasseDeriv 0 f = f := by simp only [hasseDeriv_apply, tsub_zero, Nat.choose_zero_right, Nat.cast_one, one_mul, sum_monomial_eq] #align polynomial.hasse_deriv_zero' Polynomial.hasseDeriv_zero' @[simp] theorem hasseDeriv_zero : @hasseDeriv R _ 0 = LinearMap.id := LinearMap.ext <| hasseDeriv_zero' #align polynomial.hasse_deriv_zero Polynomial.hasseDeriv_zero
Mathlib/Algebra/Polynomial/HasseDeriv.lean
93
97
theorem hasseDeriv_eq_zero_of_lt_natDegree (p : R[X]) (n : ℕ) (h : p.natDegree < n) : hasseDeriv n p = 0 := by
rw [hasseDeriv_apply, sum_def] refine Finset.sum_eq_zero fun x hx => ?_ simp [Nat.choose_eq_zero_of_lt ((le_natDegree_of_mem_supp _ hx).trans_lt h)]
import Mathlib.Algebra.GroupPower.IterateHom import Mathlib.Algebra.Ring.Divisibility.Basic import Mathlib.Data.List.Cycle import Mathlib.Data.Nat.Prime import Mathlib.Data.PNat.Basic import Mathlib.Dynamics.FixedPoints.Basic import Mathlib.GroupTheory.GroupAction.Group #align_import dynamics.periodic_pts from "leanprover-community/mathlib"@"d07245fd37786daa997af4f1a73a49fa3b748408" open Set namespace Function open Function (Commute) variable {α : Type*} {β : Type*} {f fa : α → α} {fb : β → β} {x y : α} {m n : ℕ} def IsPeriodicPt (f : α → α) (n : ℕ) (x : α) := IsFixedPt f^[n] x #align function.is_periodic_pt Function.IsPeriodicPt theorem IsFixedPt.isPeriodicPt (hf : IsFixedPt f x) (n : ℕ) : IsPeriodicPt f n x := hf.iterate n #align function.is_fixed_pt.is_periodic_pt Function.IsFixedPt.isPeriodicPt theorem is_periodic_id (n : ℕ) (x : α) : IsPeriodicPt id n x := (isFixedPt_id x).isPeriodicPt n #align function.is_periodic_id Function.is_periodic_id theorem isPeriodicPt_zero (f : α → α) (x : α) : IsPeriodicPt f 0 x := isFixedPt_id x #align function.is_periodic_pt_zero Function.isPeriodicPt_zero namespace IsPeriodicPt instance [DecidableEq α] {f : α → α} {n : ℕ} {x : α} : Decidable (IsPeriodicPt f n x) := IsFixedPt.decidable protected theorem isFixedPt (hf : IsPeriodicPt f n x) : IsFixedPt f^[n] x := hf #align function.is_periodic_pt.is_fixed_pt Function.IsPeriodicPt.isFixedPt protected theorem map (hx : IsPeriodicPt fa n x) {g : α → β} (hg : Semiconj g fa fb) : IsPeriodicPt fb n (g x) := IsFixedPt.map hx (hg.iterate_right n) #align function.is_periodic_pt.map Function.IsPeriodicPt.map theorem apply_iterate (hx : IsPeriodicPt f n x) (m : ℕ) : IsPeriodicPt f n (f^[m] x) := hx.map <| Commute.iterate_self f m #align function.is_periodic_pt.apply_iterate Function.IsPeriodicPt.apply_iterate protected theorem apply (hx : IsPeriodicPt f n x) : IsPeriodicPt f n (f x) := hx.apply_iterate 1 #align function.is_periodic_pt.apply Function.IsPeriodicPt.apply protected theorem add (hn : IsPeriodicPt f n x) (hm : IsPeriodicPt f m x) : IsPeriodicPt f (n + m) x := by rw [IsPeriodicPt, iterate_add] exact hn.comp hm #align function.is_periodic_pt.add Function.IsPeriodicPt.add theorem left_of_add (hn : IsPeriodicPt f (n + m) x) (hm : IsPeriodicPt f m x) : IsPeriodicPt f n x := by rw [IsPeriodicPt, iterate_add] at hn exact hn.left_of_comp hm #align function.is_periodic_pt.left_of_add Function.IsPeriodicPt.left_of_add theorem right_of_add (hn : IsPeriodicPt f (n + m) x) (hm : IsPeriodicPt f n x) : IsPeriodicPt f m x := by rw [add_comm] at hn exact hn.left_of_add hm #align function.is_periodic_pt.right_of_add Function.IsPeriodicPt.right_of_add protected theorem sub (hm : IsPeriodicPt f m x) (hn : IsPeriodicPt f n x) : IsPeriodicPt f (m - n) x := by rcases le_total n m with h | h · refine left_of_add ?_ hn rwa [tsub_add_cancel_of_le h] · rw [tsub_eq_zero_iff_le.mpr h] apply isPeriodicPt_zero #align function.is_periodic_pt.sub Function.IsPeriodicPt.sub protected theorem mul_const (hm : IsPeriodicPt f m x) (n : ℕ) : IsPeriodicPt f (m * n) x := by simp only [IsPeriodicPt, iterate_mul, hm.isFixedPt.iterate n] #align function.is_periodic_pt.mul_const Function.IsPeriodicPt.mul_const protected theorem const_mul (hm : IsPeriodicPt f m x) (n : ℕ) : IsPeriodicPt f (n * m) x := by simp only [mul_comm n, hm.mul_const n] #align function.is_periodic_pt.const_mul Function.IsPeriodicPt.const_mul theorem trans_dvd (hm : IsPeriodicPt f m x) {n : ℕ} (hn : m ∣ n) : IsPeriodicPt f n x := let ⟨k, hk⟩ := hn hk.symm ▸ hm.mul_const k #align function.is_periodic_pt.trans_dvd Function.IsPeriodicPt.trans_dvd protected theorem iterate (hf : IsPeriodicPt f n x) (m : ℕ) : IsPeriodicPt f^[m] n x := by rw [IsPeriodicPt, ← iterate_mul, mul_comm, iterate_mul] exact hf.isFixedPt.iterate m #align function.is_periodic_pt.iterate Function.IsPeriodicPt.iterate theorem comp {g : α → α} (hco : Commute f g) (hf : IsPeriodicPt f n x) (hg : IsPeriodicPt g n x) : IsPeriodicPt (f ∘ g) n x := by rw [IsPeriodicPt, hco.comp_iterate] exact IsFixedPt.comp hf hg #align function.is_periodic_pt.comp Function.IsPeriodicPt.comp theorem comp_lcm {g : α → α} (hco : Commute f g) (hf : IsPeriodicPt f m x) (hg : IsPeriodicPt g n x) : IsPeriodicPt (f ∘ g) (Nat.lcm m n) x := (hf.trans_dvd <| Nat.dvd_lcm_left _ _).comp hco (hg.trans_dvd <| Nat.dvd_lcm_right _ _) #align function.is_periodic_pt.comp_lcm Function.IsPeriodicPt.comp_lcm
Mathlib/Dynamics/PeriodicPts.lean
156
159
theorem left_of_comp {g : α → α} (hco : Commute f g) (hfg : IsPeriodicPt (f ∘ g) n x) (hg : IsPeriodicPt g n x) : IsPeriodicPt f n x := by
rw [IsPeriodicPt, hco.comp_iterate] at hfg exact hfg.left_of_comp hg
import Mathlib.Algebra.Order.ToIntervalMod import Mathlib.Algebra.Ring.AddAut import Mathlib.Data.Nat.Totient import Mathlib.GroupTheory.Divisible import Mathlib.Topology.Connected.PathConnected import Mathlib.Topology.IsLocalHomeomorph #align_import topology.instances.add_circle from "leanprover-community/mathlib"@"213b0cff7bc5ab6696ee07cceec80829ce42efec" noncomputable section open AddCommGroup Set Function AddSubgroup TopologicalSpace open Topology variable {𝕜 B : Type*} section Continuity variable [LinearOrderedAddCommGroup 𝕜] [Archimedean 𝕜] [TopologicalSpace 𝕜] [OrderTopology 𝕜] {p : 𝕜} (hp : 0 < p) (a x : 𝕜) theorem continuous_right_toIcoMod : ContinuousWithinAt (toIcoMod hp a) (Ici x) x := by intro s h rw [Filter.mem_map, mem_nhdsWithin_iff_exists_mem_nhds_inter] haveI : Nontrivial 𝕜 := ⟨⟨0, p, hp.ne⟩⟩ simp_rw [mem_nhds_iff_exists_Ioo_subset] at h ⊢ obtain ⟨l, u, hxI, hIs⟩ := h let d := toIcoDiv hp a x • p have hd := toIcoMod_mem_Ico hp a x simp_rw [subset_def, mem_inter_iff] refine ⟨_, ⟨l + d, min (a + p) u + d, ?_, fun x => id⟩, fun y => ?_⟩ <;> simp_rw [← sub_mem_Ioo_iff_left, mem_Ioo, lt_min_iff] · exact ⟨hxI.1, hd.2, hxI.2⟩ · rintro ⟨h, h'⟩ apply hIs rw [← toIcoMod_sub_zsmul, (toIcoMod_eq_self _).2] exacts [⟨h.1, h.2.2⟩, ⟨hd.1.trans (sub_le_sub_right h' _), h.2.1⟩] #align continuous_right_to_Ico_mod continuous_right_toIcoMod
Mathlib/Topology/Instances/AddCircle.lean
82
89
theorem continuous_left_toIocMod : ContinuousWithinAt (toIocMod hp a) (Iic x) x := by
rw [(funext fun y => Eq.trans (by rw [neg_neg]) <| toIocMod_neg _ _ _ : toIocMod hp a = (fun x => p - x) ∘ toIcoMod hp (-a) ∘ Neg.neg)] -- Porting note: added have : ContinuousNeg 𝕜 := TopologicalAddGroup.toContinuousNeg exact (continuous_sub_left _).continuousAt.comp_continuousWithinAt <| (continuous_right_toIcoMod _ _ _).comp continuous_neg.continuousWithinAt fun y => neg_le_neg
import Mathlib.Analysis.Calculus.Deriv.AffineMap import Mathlib.Analysis.Calculus.Deriv.Slope import Mathlib.Analysis.Calculus.Deriv.Mul import Mathlib.Analysis.Calculus.Deriv.Comp import Mathlib.Analysis.Calculus.LocalExtr.Rolle import Mathlib.Analysis.Convex.Normed import Mathlib.Analysis.RCLike.Basic #align_import analysis.calculus.mean_value from "leanprover-community/mathlib"@"3bce8d800a6f2b8f63fe1e588fd76a9ff4adcebe" variable {E : Type*} [NormedAddCommGroup E] [NormedSpace ℝ E] {F : Type*} [NormedAddCommGroup F] [NormedSpace ℝ F] open Metric Set Asymptotics ContinuousLinearMap Filter open scoped Classical Topology NNReal
Mathlib/Analysis/Calculus/MeanValue.lean
92
124
theorem image_le_of_liminf_slope_right_lt_deriv_boundary' {f f' : ℝ → ℝ} {a b : ℝ} (hf : ContinuousOn f (Icc a b)) -- `hf'` actually says `liminf (f z - f x) / (z - x) ≤ f' x` (hf' : ∀ x ∈ Ico a b, ∀ r, f' x < r → ∃ᶠ z in 𝓝[>] x, slope f x z < r) {B B' : ℝ → ℝ} (ha : f a ≤ B a) (hB : ContinuousOn B (Icc a b)) (hB' : ∀ x ∈ Ico a b, HasDerivWithinAt B (B' x) (Ici x) x) (bound : ∀ x ∈ Ico a b, f x = B x → f' x < B' x) : ∀ ⦃x⦄, x ∈ Icc a b → f x ≤ B x := by
change Icc a b ⊆ { x | f x ≤ B x } set s := { x | f x ≤ B x } ∩ Icc a b have A : ContinuousOn (fun x => (f x, B x)) (Icc a b) := hf.prod hB have : IsClosed s := by simp only [s, inter_comm] exact A.preimage_isClosed_of_isClosed isClosed_Icc OrderClosedTopology.isClosed_le' apply this.Icc_subset_of_forall_exists_gt ha rintro x ⟨hxB : f x ≤ B x, xab⟩ y hy cases' hxB.lt_or_eq with hxB hxB · -- If `f x < B x`, then all we need is continuity of both sides refine nonempty_of_mem (inter_mem ?_ (Ioc_mem_nhdsWithin_Ioi ⟨le_rfl, hy⟩)) have : ∀ᶠ x in 𝓝[Icc a b] x, f x < B x := A x (Ico_subset_Icc_self xab) (IsOpen.mem_nhds (isOpen_lt continuous_fst continuous_snd) hxB) have : ∀ᶠ x in 𝓝[>] x, f x < B x := nhdsWithin_le_of_mem (Icc_mem_nhdsWithin_Ioi xab) this exact this.mono fun y => le_of_lt · rcases exists_between (bound x xab hxB) with ⟨r, hfr, hrB⟩ specialize hf' x xab r hfr have HB : ∀ᶠ z in 𝓝[>] x, r < slope B x z := (hasDerivWithinAt_iff_tendsto_slope' <| lt_irrefl x).1 (hB' x xab).Ioi_of_Ici (Ioi_mem_nhds hrB) obtain ⟨z, hfz, hzB, hz⟩ : ∃ z, slope f x z < r ∧ r < slope B x z ∧ z ∈ Ioc x y := (hf'.and_eventually (HB.and (Ioc_mem_nhdsWithin_Ioi ⟨le_rfl, hy⟩))).exists refine ⟨z, ?_, hz⟩ have := (hfz.trans hzB).le rwa [slope_def_field, slope_def_field, div_le_div_right (sub_pos.2 hz.1), hxB, sub_le_sub_iff_right] at this
import Mathlib.Topology.Category.Profinite.Basic import Mathlib.CategoryTheory.Limits.Shapes.Pullbacks import Mathlib.Topology.Category.CompHaus.Limits namespace Profinite universe u w attribute [local instance] CategoryTheory.ConcreteCategory.instFunLike open CategoryTheory Limits section Pullbacks variable {X Y B : Profinite.{u}} (f : X ⟶ B) (g : Y ⟶ B) def pullback : Profinite.{u} := letI set := { xy : X × Y | f xy.fst = g xy.snd } haveI : CompactSpace set := isCompact_iff_compactSpace.mp (isClosed_eq (f.continuous.comp continuous_fst) (g.continuous.comp continuous_snd)).isCompact Profinite.of set def pullback.fst : pullback f g ⟶ X where toFun := fun ⟨⟨x, _⟩, _⟩ => x continuous_toFun := Continuous.comp continuous_fst continuous_subtype_val def pullback.snd : pullback f g ⟶ Y where toFun := fun ⟨⟨_, y⟩, _⟩ => y continuous_toFun := Continuous.comp continuous_snd continuous_subtype_val @[reassoc] lemma pullback.condition : pullback.fst f g ≫ f = pullback.snd f g ≫ g := by ext ⟨_, h⟩ exact h def pullback.lift {Z : Profinite.{u}} (a : Z ⟶ X) (b : Z ⟶ Y) (w : a ≫ f = b ≫ g) : Z ⟶ pullback f g where toFun := fun z => ⟨⟨a z, b z⟩, by apply_fun (· z) at w; exact w⟩ continuous_toFun := by apply Continuous.subtype_mk rw [continuous_prod_mk] exact ⟨a.continuous, b.continuous⟩ @[reassoc (attr := simp)] lemma pullback.lift_fst {Z : Profinite.{u}} (a : Z ⟶ X) (b : Z ⟶ Y) (w : a ≫ f = b ≫ g) : pullback.lift f g a b w ≫ pullback.fst f g = a := rfl @[reassoc (attr := simp)] lemma pullback.lift_snd {Z : Profinite.{u}} (a : Z ⟶ X) (b : Z ⟶ Y) (w : a ≫ f = b ≫ g) : pullback.lift f g a b w ≫ pullback.snd f g = b := rfl lemma pullback.hom_ext {Z : Profinite.{u}} (a b : Z ⟶ pullback f g) (hfst : a ≫ pullback.fst f g = b ≫ pullback.fst f g) (hsnd : a ≫ pullback.snd f g = b ≫ pullback.snd f g) : a = b := by ext z apply_fun (· z) at hfst hsnd apply Subtype.ext apply Prod.ext · exact hfst · exact hsnd @[simps! pt π] def pullback.cone : Limits.PullbackCone f g := Limits.PullbackCone.mk (pullback.fst f g) (pullback.snd f g) (pullback.condition f g) @[simps! lift] def pullback.isLimit : Limits.IsLimit (pullback.cone f g) := Limits.PullbackCone.isLimitAux _ (fun s => pullback.lift f g s.fst s.snd s.condition) (fun _ => pullback.lift_fst _ _ _ _ _) (fun _ => pullback.lift_snd _ _ _ _ _) (fun _ _ hm => pullback.hom_ext _ _ _ _ (hm .left) (hm .right)) section Isos noncomputable def pullbackIsoPullback : Profinite.pullback f g ≅ Limits.pullback f g := Limits.IsLimit.conePointUniqueUpToIso (pullback.isLimit f g) (Limits.limit.isLimit _) noncomputable def pullbackHomeoPullback : (Profinite.pullback f g).toCompHaus ≃ₜ (Limits.pullback f g).toCompHaus := Profinite.homeoOfIso (pullbackIsoPullback f g)
Mathlib/Topology/Category/Profinite/Limits.lean
123
126
theorem pullback_fst_eq : Profinite.pullback.fst f g = (pullbackIsoPullback f g).hom ≫ Limits.pullback.fst := by
dsimp [pullbackIsoPullback] simp only [Limits.limit.conePointUniqueUpToIso_hom_comp, pullback.cone_pt, pullback.cone_π]
import Mathlib.Topology.Separation import Mathlib.Algebra.Group.Defs #align_import topology.algebra.semigroup from "leanprover-community/mathlib"@"4c19a16e4b705bf135cf9a80ac18fcc99c438514" @[to_additive "Any nonempty compact Hausdorff additive semigroup where right-addition is continuous contains an idempotent, i.e. an `m` such that `m + m = m`"]
Mathlib/Topology/Algebra/Semigroup.lean
27
72
theorem exists_idempotent_of_compact_t2_of_continuous_mul_left {M} [Nonempty M] [Semigroup M] [TopologicalSpace M] [CompactSpace M] [T2Space M] (continuous_mul_left : ∀ r : M, Continuous (· * r)) : ∃ m : M, m * m = m := by
/- We apply Zorn's lemma to the poset of nonempty closed subsemigroups of `M`. It will turn out that any minimal element is `{m}` for an idempotent `m : M`. -/ let S : Set (Set M) := { N | IsClosed N ∧ N.Nonempty ∧ ∀ (m) (_ : m ∈ N) (m') (_ : m' ∈ N), m * m' ∈ N } rsuffices ⟨N, ⟨N_closed, ⟨m, hm⟩, N_mul⟩, N_minimal⟩ : ∃ N ∈ S, ∀ N' ∈ S, N' ⊆ N → N' = N · use m /- We now have an element `m : M` of a minimal subsemigroup `N`, and want to show `m + m = m`. We first show that every element of `N` is of the form `m' + m`. -/ have scaling_eq_self : (· * m) '' N = N := by apply N_minimal · refine ⟨(continuous_mul_left m).isClosedMap _ N_closed, ⟨_, ⟨m, hm, rfl⟩⟩, ?_⟩ rintro _ ⟨m'', hm'', rfl⟩ _ ⟨m', hm', rfl⟩ exact ⟨m'' * m * m', N_mul _ (N_mul _ hm'' _ hm) _ hm', mul_assoc _ _ _⟩ · rintro _ ⟨m', hm', rfl⟩ exact N_mul _ hm' _ hm /- In particular, this means that `m' * m = m` for some `m'`. We now use minimality again to show that this holds for all `m' ∈ N`. -/ have absorbing_eq_self : N ∩ { m' | m' * m = m } = N := by apply N_minimal · refine ⟨N_closed.inter ((T1Space.t1 m).preimage (continuous_mul_left m)), ?_, ?_⟩ · rwa [← scaling_eq_self] at hm · rintro m'' ⟨mem'', eq'' : _ = m⟩ m' ⟨mem', eq' : _ = m⟩ refine ⟨N_mul _ mem'' _ mem', ?_⟩ rw [Set.mem_setOf_eq, mul_assoc, eq', eq''] apply Set.inter_subset_left -- Thus `m * m = m` as desired. rw [← absorbing_eq_self] at hm exact hm.2 refine zorn_superset _ fun c hcs hc => ?_ refine ⟨⋂₀ c, ⟨isClosed_sInter fun t ht => (hcs ht).1, ?_, fun m hm m' hm' => ?_⟩, fun s hs => Set.sInter_subset_of_mem hs⟩ · obtain rfl | hcnemp := c.eq_empty_or_nonempty · rw [Set.sInter_empty] apply Set.univ_nonempty convert @IsCompact.nonempty_iInter_of_directed_nonempty_isCompact_isClosed _ _ _ hcnemp.coe_sort ((↑) : c → Set M) ?_ ?_ ?_ ?_ · exact Set.sInter_eq_iInter · refine DirectedOn.directed_val (IsChain.directedOn hc.symm) exacts [fun i => (hcs i.prop).2.1, fun i => (hcs i.prop).1.isCompact, fun i => (hcs i.prop).1] · rw [Set.mem_sInter] exact fun t ht => (hcs ht).2.2 m (Set.mem_sInter.mp hm t ht) m' (Set.mem_sInter.mp hm' t ht)
import Mathlib.Algebra.BigOperators.Ring import Mathlib.Combinatorics.Derangements.Basic import Mathlib.Data.Fintype.BigOperators import Mathlib.Tactic.Ring #align_import combinatorics.derangements.finite from "leanprover-community/mathlib"@"c3019c79074b0619edb4b27553a91b2e82242395" open derangements Equiv Fintype variable {α : Type*} [DecidableEq α] [Fintype α] instance : DecidablePred (derangements α) := fun _ => Fintype.decidableForallFintype -- Porting note: used to use the tactic delta_instance instance : Fintype (derangements α) := Subtype.fintype (fun (_ : Perm α) => ∀ (x_1 : α), ¬_ = x_1) theorem card_derangements_invariant {α β : Type*} [Fintype α] [DecidableEq α] [Fintype β] [DecidableEq β] (h : card α = card β) : card (derangements α) = card (derangements β) := Fintype.card_congr (Equiv.derangementsCongr <| equivOfCardEq h) #align card_derangements_invariant card_derangements_invariant theorem card_derangements_fin_add_two (n : ℕ) : card (derangements (Fin (n + 2))) = (n + 1) * card (derangements (Fin n)) + (n + 1) * card (derangements (Fin (n + 1))) := by -- get some basic results about the size of fin (n+1) plus or minus an element have h1 : ∀ a : Fin (n + 1), card ({a}ᶜ : Set (Fin (n + 1))) = card (Fin n) := by intro a simp only [Fintype.card_fin, Finset.card_fin, Fintype.card_ofFinset, Finset.filter_ne' _ a, Set.mem_compl_singleton_iff, Finset.card_erase_of_mem (Finset.mem_univ a), add_tsub_cancel_right] have h2 : card (Fin (n + 2)) = card (Option (Fin (n + 1))) := by simp only [card_fin, card_option] -- rewrite the LHS and substitute in our fintype-level equivalence simp only [card_derangements_invariant h2, card_congr (@derangementsRecursionEquiv (Fin (n + 1)) _),-- push the cardinality through the Σ and ⊕ so that we can use `card_n` card_sigma, card_sum, card_derangements_invariant (h1 _), Finset.sum_const, nsmul_eq_mul, Finset.card_fin, mul_add, Nat.cast_id] #align card_derangements_fin_add_two card_derangements_fin_add_two def numDerangements : ℕ → ℕ | 0 => 1 | 1 => 0 | n + 2 => (n + 1) * (numDerangements n + numDerangements (n + 1)) #align num_derangements numDerangements @[simp] theorem numDerangements_zero : numDerangements 0 = 1 := rfl #align num_derangements_zero numDerangements_zero @[simp] theorem numDerangements_one : numDerangements 1 = 0 := rfl #align num_derangements_one numDerangements_one theorem numDerangements_add_two (n : ℕ) : numDerangements (n + 2) = (n + 1) * (numDerangements n + numDerangements (n + 1)) := rfl #align num_derangements_add_two numDerangements_add_two theorem numDerangements_succ (n : ℕ) : (numDerangements (n + 1) : ℤ) = (n + 1) * (numDerangements n : ℤ) - (-1) ^ n := by induction' n with n hn · rfl · simp only [numDerangements_add_two, hn, pow_succ, Int.ofNat_mul, Int.ofNat_add, Int.ofNat_succ] ring #align num_derangements_succ numDerangements_succ theorem card_derangements_fin_eq_numDerangements {n : ℕ} : card (derangements (Fin n)) = numDerangements n := by induction' n using Nat.strong_induction_on with n hyp rcases n with _ | _ | n -- knock out cases 0 and 1 · rfl · rfl -- now we have n ≥ 2. rewrite everything in terms of card_derangements, so that we can use -- `card_derangements_fin_add_two` rw [numDerangements_add_two, card_derangements_fin_add_two, mul_add, hyp, hyp] <;> omega #align card_derangements_fin_eq_num_derangements card_derangements_fin_eq_numDerangements
Mathlib/Combinatorics/Derangements/Finite.lean
107
110
theorem card_derangements_eq_numDerangements (α : Type*) [Fintype α] [DecidableEq α] : card (derangements α) = numDerangements (card α) := by
rw [← card_derangements_invariant (card_fin _)] exact card_derangements_fin_eq_numDerangements
import Mathlib.MeasureTheory.Measure.Dirac set_option autoImplicit true open Set open scoped ENNReal Classical variable [MeasurableSpace α] [MeasurableSpace β] {s : Set α} noncomputable section namespace MeasureTheory.Measure def count : Measure α := sum dirac #align measure_theory.measure.count MeasureTheory.Measure.count theorem le_count_apply : ∑' _ : s, (1 : ℝ≥0∞) ≤ count s := calc (∑' _ : s, 1 : ℝ≥0∞) = ∑' i, indicator s 1 i := tsum_subtype s 1 _ ≤ ∑' i, dirac i s := ENNReal.tsum_le_tsum fun _ => le_dirac_apply _ ≤ count s := le_sum_apply _ _ #align measure_theory.measure.le_count_apply MeasureTheory.Measure.le_count_apply
Mathlib/MeasureTheory/Measure/Count.lean
39
40
theorem count_apply (hs : MeasurableSet s) : count s = ∑' i : s, 1 := by
simp only [count, sum_apply, hs, dirac_apply', ← tsum_subtype s (1 : α → ℝ≥0∞), Pi.one_apply]
import Mathlib.SetTheory.Game.State #align_import set_theory.game.domineering from "leanprover-community/mathlib"@"b134b2f5cf6dd25d4bbfd3c498b6e36c11a17225" namespace SetTheory namespace PGame namespace Domineering open Function @[simps!] def shiftUp : ℤ × ℤ ≃ ℤ × ℤ := (Equiv.refl ℤ).prodCongr (Equiv.addRight (1 : ℤ)) #align pgame.domineering.shift_up SetTheory.PGame.Domineering.shiftUp @[simps!] def shiftRight : ℤ × ℤ ≃ ℤ × ℤ := (Equiv.addRight (1 : ℤ)).prodCongr (Equiv.refl ℤ) #align pgame.domineering.shift_right SetTheory.PGame.Domineering.shiftRight -- Porting note: reducibility cannot be `local`. For now there are no dependents of this file so -- being globally reducible is fine. abbrev Board := Finset (ℤ × ℤ) #align pgame.domineering.board SetTheory.PGame.Domineering.Board def left (b : Board) : Finset (ℤ × ℤ) := b ∩ b.map shiftUp #align pgame.domineering.left SetTheory.PGame.Domineering.left def right (b : Board) : Finset (ℤ × ℤ) := b ∩ b.map shiftRight #align pgame.domineering.right SetTheory.PGame.Domineering.right theorem mem_left {b : Board} (x : ℤ × ℤ) : x ∈ left b ↔ x ∈ b ∧ (x.1, x.2 - 1) ∈ b := Finset.mem_inter.trans (and_congr Iff.rfl Finset.mem_map_equiv) #align pgame.domineering.mem_left SetTheory.PGame.Domineering.mem_left theorem mem_right {b : Board} (x : ℤ × ℤ) : x ∈ right b ↔ x ∈ b ∧ (x.1 - 1, x.2) ∈ b := Finset.mem_inter.trans (and_congr Iff.rfl Finset.mem_map_equiv) #align pgame.domineering.mem_right SetTheory.PGame.Domineering.mem_right def moveLeft (b : Board) (m : ℤ × ℤ) : Board := (b.erase m).erase (m.1, m.2 - 1) #align pgame.domineering.move_left SetTheory.PGame.Domineering.moveLeft def moveRight (b : Board) (m : ℤ × ℤ) : Board := (b.erase m).erase (m.1 - 1, m.2) #align pgame.domineering.move_right SetTheory.PGame.Domineering.moveRight theorem fst_pred_mem_erase_of_mem_right {b : Board} {m : ℤ × ℤ} (h : m ∈ right b) : (m.1 - 1, m.2) ∈ b.erase m := by rw [mem_right] at h apply Finset.mem_erase_of_ne_of_mem _ h.2 exact ne_of_apply_ne Prod.fst (pred_ne_self m.1) #align pgame.domineering.fst_pred_mem_erase_of_mem_right SetTheory.PGame.Domineering.fst_pred_mem_erase_of_mem_right theorem snd_pred_mem_erase_of_mem_left {b : Board} {m : ℤ × ℤ} (h : m ∈ left b) : (m.1, m.2 - 1) ∈ b.erase m := by rw [mem_left] at h apply Finset.mem_erase_of_ne_of_mem _ h.2 exact ne_of_apply_ne Prod.snd (pred_ne_self m.2) #align pgame.domineering.snd_pred_mem_erase_of_mem_left SetTheory.PGame.Domineering.snd_pred_mem_erase_of_mem_left theorem card_of_mem_left {b : Board} {m : ℤ × ℤ} (h : m ∈ left b) : 2 ≤ Finset.card b := by have w₁ : m ∈ b := (Finset.mem_inter.1 h).1 have w₂ : (m.1, m.2 - 1) ∈ b.erase m := snd_pred_mem_erase_of_mem_left h have i₁ := Finset.card_erase_lt_of_mem w₁ have i₂ := Nat.lt_of_le_of_lt (Nat.zero_le _) (Finset.card_erase_lt_of_mem w₂) exact Nat.lt_of_le_of_lt i₂ i₁ #align pgame.domineering.card_of_mem_left SetTheory.PGame.Domineering.card_of_mem_left theorem card_of_mem_right {b : Board} {m : ℤ × ℤ} (h : m ∈ right b) : 2 ≤ Finset.card b := by have w₁ : m ∈ b := (Finset.mem_inter.1 h).1 have w₂ := fst_pred_mem_erase_of_mem_right h have i₁ := Finset.card_erase_lt_of_mem w₁ have i₂ := Nat.lt_of_le_of_lt (Nat.zero_le _) (Finset.card_erase_lt_of_mem w₂) exact Nat.lt_of_le_of_lt i₂ i₁ #align pgame.domineering.card_of_mem_right SetTheory.PGame.Domineering.card_of_mem_right theorem moveLeft_card {b : Board} {m : ℤ × ℤ} (h : m ∈ left b) : Finset.card (moveLeft b m) + 2 = Finset.card b := by dsimp [moveLeft] rw [Finset.card_erase_of_mem (snd_pred_mem_erase_of_mem_left h)] rw [Finset.card_erase_of_mem (Finset.mem_of_mem_inter_left h)] exact tsub_add_cancel_of_le (card_of_mem_left h) #align pgame.domineering.move_left_card SetTheory.PGame.Domineering.moveLeft_card
Mathlib/SetTheory/Game/Domineering.lean
117
122
theorem moveRight_card {b : Board} {m : ℤ × ℤ} (h : m ∈ right b) : Finset.card (moveRight b m) + 2 = Finset.card b := by
dsimp [moveRight] rw [Finset.card_erase_of_mem (fst_pred_mem_erase_of_mem_right h)] rw [Finset.card_erase_of_mem (Finset.mem_of_mem_inter_left h)] exact tsub_add_cancel_of_le (card_of_mem_right h)
import Mathlib.Data.Complex.Basic import Mathlib.MeasureTheory.Integral.CircleIntegral #align_import measure_theory.integral.circle_transform from "leanprover-community/mathlib"@"d11893b411025250c8e61ff2f12ccbd7ee35ab15" open Set MeasureTheory Metric Filter Function open scoped Interval Real noncomputable section variable {E : Type*} [NormedAddCommGroup E] [NormedSpace ℂ E] (R : ℝ) (z w : ℂ) namespace Complex def circleTransform (f : ℂ → E) (θ : ℝ) : E := (2 * ↑π * I)⁻¹ • deriv (circleMap z R) θ • (circleMap z R θ - w)⁻¹ • f (circleMap z R θ) #align complex.circle_transform Complex.circleTransform def circleTransformDeriv (f : ℂ → E) (θ : ℝ) : E := (2 * ↑π * I)⁻¹ • deriv (circleMap z R) θ • ((circleMap z R θ - w) ^ 2)⁻¹ • f (circleMap z R θ) #align complex.circle_transform_deriv Complex.circleTransformDeriv theorem circleTransformDeriv_periodic (f : ℂ → E) : Periodic (circleTransformDeriv R z w f) (2 * π) := by have := periodic_circleMap simp_rw [Periodic] at * intro x simp_rw [circleTransformDeriv, this] congr 2 simp [this] #align complex.circle_transform_deriv_periodic Complex.circleTransformDeriv_periodic theorem circleTransformDeriv_eq (f : ℂ → E) : circleTransformDeriv R z w f = fun θ => (circleMap z R θ - w)⁻¹ • circleTransform R z w f θ := by ext simp_rw [circleTransformDeriv, circleTransform, ← mul_smul, ← mul_assoc] ring_nf rw [inv_pow] congr ring #align complex.circle_transform_deriv_eq Complex.circleTransformDeriv_eq theorem integral_circleTransform (f : ℂ → E) : (∫ θ : ℝ in (0)..2 * π, circleTransform R z w f θ) = (2 * ↑π * I)⁻¹ • ∮ z in C(z, R), (z - w)⁻¹ • f z := by simp_rw [circleTransform, circleIntegral, deriv_circleMap, circleMap] simp #align complex.integral_circle_transform Complex.integral_circleTransform theorem continuous_circleTransform {R : ℝ} (hR : 0 < R) {f : ℂ → E} {z w : ℂ} (hf : ContinuousOn f <| sphere z R) (hw : w ∈ ball z R) : Continuous (circleTransform R z w f) := by apply_rules [Continuous.smul, continuous_const] · simp_rw [deriv_circleMap] apply_rules [Continuous.mul, continuous_circleMap 0 R, continuous_const] · exact continuous_circleMap_inv hw · apply ContinuousOn.comp_continuous hf (continuous_circleMap z R) exact fun _ => (circleMap_mem_sphere _ hR.le) _ #align complex.continuous_circle_transform Complex.continuous_circleTransform theorem continuous_circleTransformDeriv {R : ℝ} (hR : 0 < R) {f : ℂ → E} {z w : ℂ} (hf : ContinuousOn f (sphere z R)) (hw : w ∈ ball z R) : Continuous (circleTransformDeriv R z w f) := by rw [circleTransformDeriv_eq] exact (continuous_circleMap_inv hw).smul (continuous_circleTransform hR hf hw) #align complex.continuous_circle_transform_deriv Complex.continuous_circleTransformDeriv def circleTransformBoundingFunction (R : ℝ) (z : ℂ) (w : ℂ × ℝ) : ℂ := circleTransformDeriv R z w.1 (fun _ => 1) w.2 #align complex.circle_transform_bounding_function Complex.circleTransformBoundingFunction theorem continuousOn_prod_circle_transform_function {R r : ℝ} (hr : r < R) {z : ℂ} : ContinuousOn (fun w : ℂ × ℝ => (circleMap z R w.snd - w.fst)⁻¹ ^ 2) (closedBall z r ×ˢ univ) := by simp_rw [← one_div] apply_rules [ContinuousOn.pow, ContinuousOn.div, continuousOn_const] · exact ((continuous_circleMap z R).comp_continuousOn continuousOn_snd).sub continuousOn_fst · rintro ⟨a, b⟩ ⟨ha, -⟩ have ha2 : a ∈ ball z R := closedBall_subset_ball hr ha exact sub_ne_zero.2 (circleMap_ne_mem_ball ha2 b) #align complex.continuous_on_prod_circle_transform_function Complex.continuousOn_prod_circle_transform_function theorem continuousOn_abs_circleTransformBoundingFunction {R r : ℝ} (hr : r < R) (z : ℂ) : ContinuousOn (abs ∘ circleTransformBoundingFunction R z) (closedBall z r ×ˢ univ) := by have : ContinuousOn (circleTransformBoundingFunction R z) (closedBall z r ×ˢ univ) := by apply_rules [ContinuousOn.smul, continuousOn_const] · simp only [deriv_circleMap] apply_rules [ContinuousOn.mul, (continuous_circleMap 0 R).comp_continuousOn continuousOn_snd, continuousOn_const] · simpa only [inv_pow] using continuousOn_prod_circle_transform_function hr exact this.norm #align complex.continuous_on_abs_circle_transform_bounding_function Complex.continuousOn_abs_circleTransformBoundingFunction theorem abs_circleTransformBoundingFunction_le {R r : ℝ} (hr : r < R) (hr' : 0 ≤ r) (z : ℂ) : ∃ x : closedBall z r ×ˢ [[0, 2 * π]], ∀ y : closedBall z r ×ˢ [[0, 2 * π]], abs (circleTransformBoundingFunction R z y) ≤ abs (circleTransformBoundingFunction R z x) := by have cts := continuousOn_abs_circleTransformBoundingFunction hr z have comp : IsCompact (closedBall z r ×ˢ [[0, 2 * π]]) := by apply_rules [IsCompact.prod, ProperSpace.isCompact_closedBall z r, isCompact_uIcc] have none : (closedBall z r ×ˢ [[0, 2 * π]]).Nonempty := (nonempty_closedBall.2 hr').prod nonempty_uIcc have := IsCompact.exists_isMaxOn comp none (cts.mono <| prod_mono_right (subset_univ _)) simpa [isMaxOn_iff] using this #align complex.abs_circle_transform_bounding_function_le Complex.abs_circleTransformBoundingFunction_le
Mathlib/MeasureTheory/Integral/CircleTransform.lean
133
152
theorem circleTransformDeriv_bound {R : ℝ} (hR : 0 < R) {z x : ℂ} {f : ℂ → ℂ} (hx : x ∈ ball z R) (hf : ContinuousOn f (sphere z R)) : ∃ B ε : ℝ, 0 < ε ∧ ball x ε ⊆ ball z R ∧ ∀ (t : ℝ), ∀ y ∈ ball x ε, ‖circleTransformDeriv R z y f t‖ ≤ B := by
obtain ⟨r, hr, hrx⟩ := exists_lt_mem_ball_of_mem_ball hx obtain ⟨ε', hε', H⟩ := exists_ball_subset_ball hrx obtain ⟨⟨⟨a, b⟩, ⟨ha, hb⟩⟩, hab⟩ := abs_circleTransformBoundingFunction_le hr (pos_of_mem_ball hrx).le z let V : ℝ → ℂ → ℂ := fun θ w => circleTransformDeriv R z w (fun _ => 1) θ obtain ⟨X, -, HX2⟩ := (isCompact_sphere z R).exists_isMaxOn (NormedSpace.sphere_nonempty.2 hR.le) hf.norm refine ⟨abs (V b a) * abs (f X), ε', hε', H.trans (ball_subset_ball hr.le), fun y v hv ↦ ?_⟩ obtain ⟨y1, hy1, hfun⟩ := Periodic.exists_mem_Ico₀ (circleTransformDeriv_periodic R z v f) Real.two_pi_pos y have hy2 : y1 ∈ [[0, 2 * π]] := Icc_subset_uIcc <| Ico_subset_Icc_self hy1 simp only [isMaxOn_iff, mem_sphere_iff_norm, norm_eq_abs] at HX2 have := mul_le_mul (hab ⟨⟨v, y1⟩, ⟨ball_subset_closedBall (H hv), hy2⟩⟩) (HX2 (circleMap z R y1) (circleMap_mem_sphere z hR.le y1)) (Complex.abs.nonneg _) (Complex.abs.nonneg _) rw [hfun] simpa [V, circleTransformBoundingFunction, circleTransformDeriv, mul_assoc] using this
import Mathlib.Data.Real.Irrational import Mathlib.Data.Nat.Fib.Basic import Mathlib.Data.Fin.VecNotation import Mathlib.Algebra.LinearRecurrence import Mathlib.Tactic.NormNum.NatFib import Mathlib.Tactic.NormNum.Prime #align_import data.real.golden_ratio from "leanprover-community/mathlib"@"2196ab363eb097c008d4497125e0dde23fb36db2" noncomputable section open Polynomial abbrev goldenRatio : ℝ := (1 + √5) / 2 #align golden_ratio goldenRatio abbrev goldenConj : ℝ := (1 - √5) / 2 #align golden_conj goldenConj @[inherit_doc goldenRatio] scoped[goldenRatio] notation "φ" => goldenRatio @[inherit_doc goldenConj] scoped[goldenRatio] notation "ψ" => goldenConj open Real goldenRatio theorem inv_gold : φ⁻¹ = -ψ := by have : 1 + √5 ≠ 0 := ne_of_gt (add_pos (by norm_num) <| Real.sqrt_pos.mpr (by norm_num)) field_simp [sub_mul, mul_add] norm_num #align inv_gold inv_gold theorem inv_goldConj : ψ⁻¹ = -φ := by rw [inv_eq_iff_eq_inv, ← neg_inv, ← neg_eq_iff_eq_neg] exact inv_gold.symm #align inv_gold_conj inv_goldConj @[simp] theorem gold_mul_goldConj : φ * ψ = -1 := by field_simp rw [← sq_sub_sq] norm_num #align gold_mul_gold_conj gold_mul_goldConj @[simp] theorem goldConj_mul_gold : ψ * φ = -1 := by rw [mul_comm] exact gold_mul_goldConj #align gold_conj_mul_gold goldConj_mul_gold @[simp]
Mathlib/Data/Real/GoldenRatio.lean
70
72
theorem gold_add_goldConj : φ + ψ = 1 := by
rw [goldenRatio, goldenConj] ring
import Mathlib.Algebra.Polynomial.Mirror import Mathlib.Analysis.Complex.Polynomial #align_import data.polynomial.unit_trinomial from "leanprover-community/mathlib"@"302eab4f46abb63de520828de78c04cb0f9b5836" namespace Polynomial open scoped Polynomial open Finset section Semiring variable {R : Type*} [Semiring R] (k m n : ℕ) (u v w : R) noncomputable def trinomial := C u * X ^ k + C v * X ^ m + C w * X ^ n #align polynomial.trinomial Polynomial.trinomial theorem trinomial_def : trinomial k m n u v w = C u * X ^ k + C v * X ^ m + C w * X ^ n := rfl #align polynomial.trinomial_def Polynomial.trinomial_def variable {k m n u v w}
Mathlib/Algebra/Polynomial/UnitTrinomial.lean
49
52
theorem trinomial_leading_coeff' (hkm : k < m) (hmn : m < n) : (trinomial k m n u v w).coeff n = w := by
rw [trinomial_def, coeff_add, coeff_add, coeff_C_mul_X_pow, coeff_C_mul_X_pow, coeff_C_mul_X_pow, if_neg (hkm.trans hmn).ne', if_neg hmn.ne', if_pos rfl, zero_add, zero_add]
import Mathlib.Order.Lattice import Mathlib.Data.List.Sort import Mathlib.Logic.Equiv.Fin import Mathlib.Logic.Equiv.Functor import Mathlib.Data.Fintype.Card import Mathlib.Order.RelSeries #align_import order.jordan_holder from "leanprover-community/mathlib"@"91288e351d51b3f0748f0a38faa7613fb0ae2ada" universe u open Set RelSeries class JordanHolderLattice (X : Type u) [Lattice X] where IsMaximal : X → X → Prop lt_of_isMaximal : ∀ {x y}, IsMaximal x y → x < y sup_eq_of_isMaximal : ∀ {x y z}, IsMaximal x z → IsMaximal y z → x ≠ y → x ⊔ y = z isMaximal_inf_left_of_isMaximal_sup : ∀ {x y}, IsMaximal x (x ⊔ y) → IsMaximal y (x ⊔ y) → IsMaximal (x ⊓ y) x Iso : X × X → X × X → Prop iso_symm : ∀ {x y}, Iso x y → Iso y x iso_trans : ∀ {x y z}, Iso x y → Iso y z → Iso x z second_iso : ∀ {x y}, IsMaximal x (x ⊔ y) → Iso (x, x ⊔ y) (x ⊓ y, y) #align jordan_holder_lattice JordanHolderLattice namespace JordanHolderLattice variable {X : Type u} [Lattice X] [JordanHolderLattice X] theorem isMaximal_inf_right_of_isMaximal_sup {x y : X} (hxz : IsMaximal x (x ⊔ y)) (hyz : IsMaximal y (x ⊔ y)) : IsMaximal (x ⊓ y) y := by rw [inf_comm] rw [sup_comm] at hxz hyz exact isMaximal_inf_left_of_isMaximal_sup hyz hxz #align jordan_holder_lattice.is_maximal_inf_right_of_is_maximal_sup JordanHolderLattice.isMaximal_inf_right_of_isMaximal_sup theorem isMaximal_of_eq_inf (x b : X) {a y : X} (ha : x ⊓ y = a) (hxy : x ≠ y) (hxb : IsMaximal x b) (hyb : IsMaximal y b) : IsMaximal a y := by have hb : x ⊔ y = b := sup_eq_of_isMaximal hxb hyb hxy substs a b exact isMaximal_inf_right_of_isMaximal_sup hxb hyb #align jordan_holder_lattice.is_maximal_of_eq_inf JordanHolderLattice.isMaximal_of_eq_inf
Mathlib/Order/JordanHolder.lean
116
117
theorem second_iso_of_eq {x y a b : X} (hm : IsMaximal x a) (ha : x ⊔ y = a) (hb : x ⊓ y = b) : Iso (x, a) (b, y) := by
substs a b; exact second_iso hm
import Mathlib.RepresentationTheory.Rep import Mathlib.Algebra.Category.FGModuleCat.Limits import Mathlib.CategoryTheory.Preadditive.Schur import Mathlib.RepresentationTheory.Basic #align_import representation_theory.fdRep from "leanprover-community/mathlib"@"19a70dceb9dff0994b92d2dd049de7d84d28112b" suppress_compilation universe u open CategoryTheory open CategoryTheory.Limits set_option linter.uppercaseLean3 false -- `FdRep` abbrev FdRep (k G : Type u) [Field k] [Monoid G] := Action (FGModuleCat.{u} k) (MonCat.of G) #align fdRep FdRep namespace FdRep variable {k G : Type u} [Field k] [Monoid G] -- Porting note: `@[derive]` didn't work for `FdRep`. Add the 4 instances here. instance : LargeCategory (FdRep k G) := inferInstance instance : ConcreteCategory (FdRep k G) := inferInstance instance : Preadditive (FdRep k G) := inferInstance instance : HasFiniteLimits (FdRep k G) := inferInstance instance : Linear k (FdRep k G) := by infer_instance instance : CoeSort (FdRep k G) (Type u) := ConcreteCategory.hasCoeToSort _ instance (V : FdRep k G) : AddCommGroup V := by change AddCommGroup ((forget₂ (FdRep k G) (FGModuleCat k)).obj V).obj; infer_instance instance (V : FdRep k G) : Module k V := by change Module k ((forget₂ (FdRep k G) (FGModuleCat k)).obj V).obj; infer_instance instance (V : FdRep k G) : FiniteDimensional k V := by change FiniteDimensional k ((forget₂ (FdRep k G) (FGModuleCat k)).obj V); infer_instance instance (V W : FdRep k G) : FiniteDimensional k (V ⟶ W) := FiniteDimensional.of_injective ((forget₂ (FdRep k G) (FGModuleCat k)).mapLinearMap k) (Functor.map_injective (forget₂ (FdRep k G) (FGModuleCat k))) def ρ (V : FdRep k G) : G →* V →ₗ[k] V := Action.ρ V #align fdRep.ρ FdRep.ρ def isoToLinearEquiv {V W : FdRep k G} (i : V ≅ W) : V ≃ₗ[k] W := FGModuleCat.isoToLinearEquiv ((Action.forget (FGModuleCat k) (MonCat.of G)).mapIso i) #align fdRep.iso_to_linear_equiv FdRep.isoToLinearEquiv
Mathlib/RepresentationTheory/FdRep.lean
95
100
theorem Iso.conj_ρ {V W : FdRep k G} (i : V ≅ W) (g : G) : W.ρ g = (FdRep.isoToLinearEquiv i).conj (V.ρ g) := by
-- Porting note: Changed `rw` to `erw` erw [FdRep.isoToLinearEquiv, ← FGModuleCat.Iso.conj_eq_conj, Iso.conj_apply] rw [Iso.eq_inv_comp ((Action.forget (FGModuleCat k) (MonCat.of G)).mapIso i)] exact (i.hom.comm g).symm
import Mathlib.Algebra.CharP.Basic import Mathlib.Algebra.CharP.Algebra import Mathlib.Data.Nat.Prime #align_import algebra.char_p.exp_char from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a" universe u variable (R : Type u) section Semiring variable [Semiring R] class inductive ExpChar (R : Type u) [Semiring R] : ℕ → Prop | zero [CharZero R] : ExpChar R 1 | prime {q : ℕ} (hprime : q.Prime) [hchar : CharP R q] : ExpChar R q #align exp_char ExpChar #align exp_char.prime ExpChar.prime instance expChar_prime (p) [CharP R p] [Fact p.Prime] : ExpChar R p := ExpChar.prime Fact.out instance expChar_zero [CharZero R] : ExpChar R 1 := ExpChar.zero instance (S : Type*) [Semiring S] (p) [ExpChar R p] [ExpChar S p] : ExpChar (R × S) p := by obtain hp | ⟨hp⟩ := ‹ExpChar R p› · have := Prod.charZero_of_left R S; exact .zero obtain _ | _ := ‹ExpChar S p› · exact (Nat.not_prime_one hp).elim · have := Prod.charP R S p; exact .prime hp variable {R} in theorem ExpChar.eq {p q : ℕ} (hp : ExpChar R p) (hq : ExpChar R q) : p = q := by cases' hp with hp _ hp' hp · cases' hq with hq _ hq' hq exacts [rfl, False.elim (Nat.not_prime_zero (CharP.eq R hq (CharP.ofCharZero R) ▸ hq'))] · cases' hq with hq _ hq' hq exacts [False.elim (Nat.not_prime_zero (CharP.eq R hp (CharP.ofCharZero R) ▸ hp')), CharP.eq R hp hq] theorem ExpChar.congr {p : ℕ} (q : ℕ) [hq : ExpChar R q] (h : q = p) : ExpChar R p := h ▸ hq noncomputable def ringExpChar (R : Type*) [NonAssocSemiring R] : ℕ := max (ringChar R) 1 theorem ringExpChar.eq (q : ℕ) [h : ExpChar R q] : ringExpChar R = q := by cases' h with _ _ h _ · haveI := CharP.ofCharZero R rw [ringExpChar, ringChar.eq R 0]; rfl rw [ringExpChar, ringChar.eq R q] exact Nat.max_eq_left h.one_lt.le @[simp] theorem ringExpChar.eq_one (R : Type*) [NonAssocSemiring R] [CharZero R] : ringExpChar R = 1 := by rw [ringExpChar, ringChar.eq_zero, max_eq_right zero_le_one] theorem expChar_one_of_char_zero (q : ℕ) [hp : CharP R 0] [hq : ExpChar R q] : q = 1 := by cases' hq with q hq_one hq_prime hq_hchar · rfl · exact False.elim <| hq_prime.ne_zero <| hq_hchar.eq R hp #align exp_char_one_of_char_zero expChar_one_of_char_zero theorem char_eq_expChar_iff (p q : ℕ) [hp : CharP R p] [hq : ExpChar R q] : p = q ↔ p.Prime := by cases' hq with q hq_one hq_prime hq_hchar · rw [(CharP.eq R hp inferInstance : p = 0)] decide · exact ⟨fun hpq => hpq.symm ▸ hq_prime, fun _ => CharP.eq R hp hq_hchar⟩ #align char_eq_exp_char_iff char_eq_expChar_iff section Nontrivial variable [Nontrivial R] theorem char_zero_of_expChar_one (p : ℕ) [hp : CharP R p] [hq : ExpChar R 1] : p = 0 := by cases hq · exact CharP.eq R hp inferInstance · exact False.elim (CharP.char_ne_one R 1 rfl) #align char_zero_of_exp_char_one char_zero_of_expChar_one -- This could be an instance, but there are no `ExpChar R 1` instances in mathlib. theorem charZero_of_expChar_one' [hq : ExpChar R 1] : CharZero R := by cases hq · assumption · exact False.elim (CharP.char_ne_one R 1 rfl) #align char_zero_of_exp_char_one' charZero_of_expChar_one'
Mathlib/Algebra/CharP/ExpChar.lean
120
125
theorem expChar_one_iff_char_zero (p q : ℕ) [CharP R p] [ExpChar R q] : q = 1 ↔ p = 0 := by
constructor · rintro rfl exact char_zero_of_expChar_one R p · rintro rfl exact expChar_one_of_char_zero R q
import Mathlib.MeasureTheory.Group.Measure import Mathlib.MeasureTheory.Integral.IntegrableOn import Mathlib.MeasureTheory.Function.LocallyIntegrable open Asymptotics MeasureTheory Set Filter variable {α E F : Type*} [MeasurableSpace α] [NormedAddCommGroup E] [NormedAddCommGroup F] {f : α → E} {g : α → F} {a b : α} {μ : Measure α} {l : Filter α} theorem _root_.Asymptotics.IsBigO.integrableAtFilter [IsMeasurablyGenerated l] (hf : f =O[l] g) (hfm : StronglyMeasurableAtFilter f l μ) (hg : IntegrableAtFilter g l μ) : IntegrableAtFilter f l μ := by obtain ⟨C, hC⟩ := hf.bound obtain ⟨s, hsl, hsm, hfg, hf, hg⟩ := (hC.smallSets.and <| hfm.eventually.and hg.eventually).exists_measurable_mem_of_smallSets refine ⟨s, hsl, (hg.norm.const_mul C).mono hf ?_⟩ refine (ae_restrict_mem hsm).mono fun x hx ↦ ?_ exact (hfg x hx).trans (le_abs_self _) theorem _root_.Asymptotics.IsBigO.integrable (hfm : AEStronglyMeasurable f μ) (hf : f =O[⊤] g) (hg : Integrable g μ) : Integrable f μ := by rewrite [← integrableAtFilter_top] at * exact hf.integrableAtFilter ⟨univ, univ_mem, hfm.restrict⟩ hg variable [TopologicalSpace α] [SecondCountableTopology α] namespace MeasureTheory theorem LocallyIntegrable.integrable_of_isBigO_cocompact [IsMeasurablyGenerated (cocompact α)] (hf : LocallyIntegrable f μ) (ho : f =O[cocompact α] g) (hg : IntegrableAtFilter g (cocompact α) μ) : Integrable f μ := by refine integrable_iff_integrableAtFilter_cocompact.mpr ⟨ho.integrableAtFilter ?_ hg, hf⟩ exact hf.aestronglyMeasurable.stronglyMeasurableAtFilter section LinearOrder variable [LinearOrder α] [CompactIccSpace α] {g' : α → F} theorem LocallyIntegrable.integrable_of_isBigO_atBot_atTop [IsMeasurablyGenerated (atBot (α := α))] [IsMeasurablyGenerated (atTop (α := α))] (hf : LocallyIntegrable f μ) (ho : f =O[atBot] g) (hg : IntegrableAtFilter g atBot μ) (ho' : f =O[atTop] g') (hg' : IntegrableAtFilter g' atTop μ) : Integrable f μ := by refine integrable_iff_integrableAtFilter_atBot_atTop.mpr ⟨⟨ho.integrableAtFilter ?_ hg, ho'.integrableAtFilter ?_ hg'⟩, hf⟩ all_goals exact hf.aestronglyMeasurable.stronglyMeasurableAtFilter
Mathlib/MeasureTheory/Integral/Asymptotics.lean
81
85
theorem LocallyIntegrableOn.integrableOn_of_isBigO_atBot [IsMeasurablyGenerated (atBot (α := α))] (hf : LocallyIntegrableOn f (Iic a) μ) (ho : f =O[atBot] g) (hg : IntegrableAtFilter g atBot μ) : IntegrableOn f (Iic a) μ := by
refine integrableOn_Iic_iff_integrableAtFilter_atBot.mpr ⟨ho.integrableAtFilter ?_ hg, hf⟩ exact ⟨Iic a, Iic_mem_atBot a, hf.aestronglyMeasurable⟩
import Mathlib.Analysis.SpecialFunctions.Pow.Real #align_import analysis.special_functions.pow.nnreal from "leanprover-community/mathlib"@"4fa54b337f7d52805480306db1b1439c741848c8" noncomputable section open scoped Classical open Real NNReal ENNReal ComplexConjugate open Finset Function Set namespace NNReal variable {w x y z : ℝ} noncomputable def rpow (x : ℝ≥0) (y : ℝ) : ℝ≥0 := ⟨(x : ℝ) ^ y, Real.rpow_nonneg x.2 y⟩ #align nnreal.rpow NNReal.rpow noncomputable instance : Pow ℝ≥0 ℝ := ⟨rpow⟩ @[simp] theorem rpow_eq_pow (x : ℝ≥0) (y : ℝ) : rpow x y = x ^ y := rfl #align nnreal.rpow_eq_pow NNReal.rpow_eq_pow @[simp, norm_cast] theorem coe_rpow (x : ℝ≥0) (y : ℝ) : ((x ^ y : ℝ≥0) : ℝ) = (x : ℝ) ^ y := rfl #align nnreal.coe_rpow NNReal.coe_rpow @[simp] theorem rpow_zero (x : ℝ≥0) : x ^ (0 : ℝ) = 1 := NNReal.eq <| Real.rpow_zero _ #align nnreal.rpow_zero NNReal.rpow_zero @[simp]
Mathlib/Analysis/SpecialFunctions/Pow/NNReal.lean
57
59
theorem rpow_eq_zero_iff {x : ℝ≥0} {y : ℝ} : x ^ y = 0 ↔ x = 0 ∧ y ≠ 0 := by
rw [← NNReal.coe_inj, coe_rpow, ← NNReal.coe_eq_zero] exact Real.rpow_eq_zero_iff_of_nonneg x.2
import Mathlib.Analysis.Convex.Gauge import Mathlib.Analysis.Convex.Normed open Metric Bornology Filter Set open scoped NNReal Topology Pointwise noncomputable section section Module variable {E : Type*} [AddCommGroup E] [Module ℝ E] def gaugeRescale (s t : Set E) (x : E) : E := (gauge s x / gauge t x) • x theorem gaugeRescale_def (s t : Set E) (x : E) : gaugeRescale s t x = (gauge s x / gauge t x) • x := rfl @[simp] theorem gaugeRescale_zero (s t : Set E) : gaugeRescale s t 0 = 0 := smul_zero _ theorem gaugeRescale_smul (s t : Set E) {c : ℝ} (hc : 0 ≤ c) (x : E) : gaugeRescale s t (c • x) = c • gaugeRescale s t x := by simp only [gaugeRescale, gauge_smul_of_nonneg hc, smul_smul, smul_eq_mul] rw [mul_div_mul_comm, mul_right_comm, div_self_mul_self] variable [TopologicalSpace E] [T1Space E] theorem gaugeRescale_self_apply {s : Set E} (hsa : Absorbent ℝ s) (hsb : IsVonNBounded ℝ s) (x : E) : gaugeRescale s s x = x := by rcases eq_or_ne x 0 with rfl | hx; · simp rw [gaugeRescale, div_self, one_smul] exact ((gauge_pos hsa hsb).2 hx).ne' theorem gaugeRescale_self {s : Set E} (hsa : Absorbent ℝ s) (hsb : IsVonNBounded ℝ s) : gaugeRescale s s = id := funext <| gaugeRescale_self_apply hsa hsb theorem gauge_gaugeRescale' (s : Set E) {t : Set E} {x : E} (hx : gauge t x ≠ 0) : gauge t (gaugeRescale s t x) = gauge s x := by rw [gaugeRescale, gauge_smul_of_nonneg (div_nonneg (gauge_nonneg _) (gauge_nonneg _)), smul_eq_mul, div_mul_cancel₀ _ hx] theorem gauge_gaugeRescale (s : Set E) {t : Set E} (hta : Absorbent ℝ t) (htb : IsVonNBounded ℝ t) (x : E) : gauge t (gaugeRescale s t x) = gauge s x := by rcases eq_or_ne x 0 with rfl | hx · simp · exact gauge_gaugeRescale' s ((gauge_pos hta htb).2 hx).ne' theorem gauge_gaugeRescale_le (s t : Set E) (x : E) : gauge t (gaugeRescale s t x) ≤ gauge s x := by by_cases hx : gauge t x = 0 · simp [gaugeRescale, hx, gauge_nonneg] · exact (gauge_gaugeRescale' s hx).le theorem gaugeRescale_gaugeRescale {s t u : Set E} (hta : Absorbent ℝ t) (htb : IsVonNBounded ℝ t) (x : E) : gaugeRescale t u (gaugeRescale s t x) = gaugeRescale s u x := by rcases eq_or_ne x 0 with rfl | hx; · simp rw [gaugeRescale_def s t x, gaugeRescale_smul, gaugeRescale, gaugeRescale, smul_smul, div_mul_div_cancel] exacts [((gauge_pos hta htb).2 hx).ne', div_nonneg (gauge_nonneg _) (gauge_nonneg _)] def gaugeRescaleEquiv (s t : Set E) (hsa : Absorbent ℝ s) (hsb : IsVonNBounded ℝ s) (hta : Absorbent ℝ t) (htb : IsVonNBounded ℝ t) : E ≃ E where toFun := gaugeRescale s t invFun := gaugeRescale t s left_inv x := by rw [gaugeRescale_gaugeRescale, gaugeRescale_self_apply] <;> assumption right_inv x := by rw [gaugeRescale_gaugeRescale, gaugeRescale_self_apply] <;> assumption variable [TopologicalAddGroup E] [ContinuousSMul ℝ E] {s t : Set E} theorem mapsTo_gaugeRescale_interior (h₀ : t ∈ 𝓝 0) (hc : Convex ℝ t) : MapsTo (gaugeRescale s t) (interior s) (interior t) := fun x hx ↦ by rw [← gauge_lt_one_iff_mem_interior] <;> try assumption exact (gauge_gaugeRescale_le _ _ _).trans_lt (interior_subset_gauge_lt_one _ hx) theorem mapsTo_gaugeRescale_closure {s t : Set E} (hsc : Convex ℝ s) (hs₀ : s ∈ 𝓝 0) (htc : Convex ℝ t) (ht₀ : 0 ∈ t) (hta : Absorbent ℝ t) : MapsTo (gaugeRescale s t) (closure s) (closure t) := fun _x hx ↦ mem_closure_of_gauge_le_one htc ht₀ hta <| (gauge_gaugeRescale_le _ _ _).trans <| (gauge_le_one_iff_mem_closure hsc hs₀).2 hx
Mathlib/Analysis/Convex/GaugeRescale.lean
103
114
theorem continuous_gaugeRescale {s t : Set E} (hs : Convex ℝ s) (hs₀ : s ∈ 𝓝 0) (ht : Convex ℝ t) (ht₀ : t ∈ 𝓝 0) (htb : IsVonNBounded ℝ t) : Continuous (gaugeRescale s t) := by
have hta : Absorbent ℝ t := absorbent_nhds_zero ht₀ refine continuous_iff_continuousAt.2 fun x ↦ ?_ rcases eq_or_ne x 0 with rfl | hx · rw [ContinuousAt, gaugeRescale_zero] nth_rewrite 2 [← comap_gauge_nhds_zero htb ht₀] simp only [tendsto_comap_iff, (· ∘ ·), gauge_gaugeRescale _ hta htb] exact tendsto_gauge_nhds_zero hs₀ · exact ((continuousAt_gauge hs hs₀).div (continuousAt_gauge ht ht₀) ((gauge_pos hta htb).2 hx).ne').smul continuousAt_id
import Mathlib.Analysis.InnerProductSpace.GramSchmidtOrtho import Mathlib.LinearAlgebra.Orientation #align_import analysis.inner_product_space.orientation from "leanprover-community/mathlib"@"bd65478311e4dfd41f48bf38c7e3b02fb75d0163" noncomputable section variable {E : Type*} [NormedAddCommGroup E] [InnerProductSpace ℝ E] open FiniteDimensional open scoped RealInnerProductSpace namespace OrthonormalBasis variable {ι : Type*} [Fintype ι] [DecidableEq ι] [ne : Nonempty ι] (e f : OrthonormalBasis ι ℝ E) (x : Orientation ℝ E ι) theorem det_to_matrix_orthonormalBasis_of_same_orientation (h : e.toBasis.orientation = f.toBasis.orientation) : e.toBasis.det f = 1 := by apply (e.det_to_matrix_orthonormalBasis_real f).resolve_right have : 0 < e.toBasis.det f := by rw [e.toBasis.orientation_eq_iff_det_pos] at h simpa using h linarith #align orthonormal_basis.det_to_matrix_orthonormal_basis_of_same_orientation OrthonormalBasis.det_to_matrix_orthonormalBasis_of_same_orientation theorem det_to_matrix_orthonormalBasis_of_opposite_orientation (h : e.toBasis.orientation ≠ f.toBasis.orientation) : e.toBasis.det f = -1 := by contrapose! h simp [e.toBasis.orientation_eq_iff_det_pos, (e.det_to_matrix_orthonormalBasis_real f).resolve_right h] #align orthonormal_basis.det_to_matrix_orthonormal_basis_of_opposite_orientation OrthonormalBasis.det_to_matrix_orthonormalBasis_of_opposite_orientation variable {e f} theorem same_orientation_iff_det_eq_det : e.toBasis.det = f.toBasis.det ↔ e.toBasis.orientation = f.toBasis.orientation := by constructor · intro h dsimp [Basis.orientation] congr · intro h rw [e.toBasis.det.eq_smul_basis_det f.toBasis] simp [e.det_to_matrix_orthonormalBasis_of_same_orientation f h] #align orthonormal_basis.same_orientation_iff_det_eq_det OrthonormalBasis.same_orientation_iff_det_eq_det variable (e f)
Mathlib/Analysis/InnerProductSpace/Orientation.lean
91
96
theorem det_eq_neg_det_of_opposite_orientation (h : e.toBasis.orientation ≠ f.toBasis.orientation) : e.toBasis.det = -f.toBasis.det := by
rw [e.toBasis.det.eq_smul_basis_det f.toBasis] -- Porting note: added `neg_one_smul` with explicit type simp [e.det_to_matrix_orthonormalBasis_of_opposite_orientation f h, neg_one_smul ℝ (M := E [⋀^ι]→ₗ[ℝ] ℝ)]
import Mathlib.LinearAlgebra.AffineSpace.AffineEquiv #align_import linear_algebra.affine_space.affine_subspace from "leanprover-community/mathlib"@"e96bdfbd1e8c98a09ff75f7ac6204d142debc840" noncomputable section open Affine open Set section variable (k : Type*) {V : Type*} {P : Type*} [Ring k] [AddCommGroup V] [Module k V] variable [AffineSpace V P] def vectorSpan (s : Set P) : Submodule k V := Submodule.span k (s -ᵥ s) #align vector_span vectorSpan theorem vectorSpan_def (s : Set P) : vectorSpan k s = Submodule.span k (s -ᵥ s) := rfl #align vector_span_def vectorSpan_def theorem vectorSpan_mono {s₁ s₂ : Set P} (h : s₁ ⊆ s₂) : vectorSpan k s₁ ≤ vectorSpan k s₂ := Submodule.span_mono (vsub_self_mono h) #align vector_span_mono vectorSpan_mono variable (P) @[simp] theorem vectorSpan_empty : vectorSpan k (∅ : Set P) = (⊥ : Submodule k V) := by rw [vectorSpan_def, vsub_empty, Submodule.span_empty] #align vector_span_empty vectorSpan_empty variable {P} @[simp] theorem vectorSpan_singleton (p : P) : vectorSpan k ({p} : Set P) = ⊥ := by simp [vectorSpan_def] #align vector_span_singleton vectorSpan_singleton theorem vsub_set_subset_vectorSpan (s : Set P) : s -ᵥ s ⊆ ↑(vectorSpan k s) := Submodule.subset_span #align vsub_set_subset_vector_span vsub_set_subset_vectorSpan theorem vsub_mem_vectorSpan {s : Set P} {p1 p2 : P} (hp1 : p1 ∈ s) (hp2 : p2 ∈ s) : p1 -ᵥ p2 ∈ vectorSpan k s := vsub_set_subset_vectorSpan k s (vsub_mem_vsub hp1 hp2) #align vsub_mem_vector_span vsub_mem_vectorSpan def spanPoints (s : Set P) : Set P := { p | ∃ p1 ∈ s, ∃ v ∈ vectorSpan k s, p = v +ᵥ p1 } #align span_points spanPoints theorem mem_spanPoints (p : P) (s : Set P) : p ∈ s → p ∈ spanPoints k s | hp => ⟨p, hp, 0, Submodule.zero_mem _, (zero_vadd V p).symm⟩ #align mem_span_points mem_spanPoints theorem subset_spanPoints (s : Set P) : s ⊆ spanPoints k s := fun p => mem_spanPoints k p s #align subset_span_points subset_spanPoints @[simp] theorem spanPoints_nonempty (s : Set P) : (spanPoints k s).Nonempty ↔ s.Nonempty := by constructor · contrapose rw [Set.not_nonempty_iff_eq_empty, Set.not_nonempty_iff_eq_empty] intro h simp [h, spanPoints] · exact fun h => h.mono (subset_spanPoints _ _) #align span_points_nonempty spanPoints_nonempty
Mathlib/LinearAlgebra/AffineSpace/AffineSubspace.lean
128
132
theorem vadd_mem_spanPoints_of_mem_spanPoints_of_mem_vectorSpan {s : Set P} {p : P} {v : V} (hp : p ∈ spanPoints k s) (hv : v ∈ vectorSpan k s) : v +ᵥ p ∈ spanPoints k s := by
rcases hp with ⟨p2, ⟨hp2, ⟨v2, ⟨hv2, hv2p⟩⟩⟩⟩ rw [hv2p, vadd_vadd] exact ⟨p2, hp2, v + v2, (vectorSpan k s).add_mem hv hv2, rfl⟩
import Mathlib.Data.Set.Pointwise.SMul import Mathlib.GroupTheory.GroupAction.Hom open Set Pointwise
Mathlib/GroupTheory/GroupAction/Pointwise.lean
33
41
theorem MulAction.smul_bijective_of_is_unit {M : Type*} [Monoid M] {α : Type*} [MulAction M α] {m : M} (hm : IsUnit m) : Function.Bijective (fun (a : α) ↦ m • a) := by
lift m to Mˣ using hm rw [Function.bijective_iff_has_inverse] use fun a ↦ m⁻¹ • a constructor · intro x; simp [← Units.smul_def] · intro x; simp [← Units.smul_def]
import Mathlib.Data.List.Forall2 import Mathlib.Data.Set.Pairwise.Basic import Mathlib.Init.Data.Fin.Basic #align_import data.list.nodup from "leanprover-community/mathlib"@"c227d107bbada5d0d9d20287e3282c0a7f1651a0" universe u v open Nat Function variable {α : Type u} {β : Type v} {l l₁ l₂ : List α} {r : α → α → Prop} {a b : α} namespace List @[simp] theorem forall_mem_ne {a : α} {l : List α} : (∀ a' : α, a' ∈ l → ¬a = a') ↔ a ∉ l := ⟨fun h m => h _ m rfl, fun h _ m e => h (e.symm ▸ m)⟩ #align list.forall_mem_ne List.forall_mem_ne @[simp] theorem nodup_nil : @Nodup α [] := Pairwise.nil #align list.nodup_nil List.nodup_nil @[simp]
Mathlib/Data/List/Nodup.lean
39
40
theorem nodup_cons {a : α} {l : List α} : Nodup (a :: l) ↔ a ∉ l ∧ Nodup l := by
simp only [Nodup, pairwise_cons, forall_mem_ne]
import Mathlib.Probability.Variance #align_import probability.moments from "leanprover-community/mathlib"@"85453a2a14be8da64caf15ca50930cf4c6e5d8de" open MeasureTheory Filter Finset Real noncomputable section open scoped MeasureTheory ProbabilityTheory ENNReal NNReal namespace ProbabilityTheory variable {Ω ι : Type*} {m : MeasurableSpace Ω} {X : Ω → ℝ} {p : ℕ} {μ : Measure Ω} def moment (X : Ω → ℝ) (p : ℕ) (μ : Measure Ω) : ℝ := μ[X ^ p] #align probability_theory.moment ProbabilityTheory.moment def centralMoment (X : Ω → ℝ) (p : ℕ) (μ : Measure Ω) : ℝ := by have m := fun (x : Ω) => μ[X] -- Porting note: Lean deems `μ[(X - fun x => μ[X]) ^ p]` ambiguous exact μ[(X - m) ^ p] #align probability_theory.central_moment ProbabilityTheory.centralMoment @[simp] theorem moment_zero (hp : p ≠ 0) : moment 0 p μ = 0 := by simp only [moment, hp, zero_pow, Ne, not_false_iff, Pi.zero_apply, integral_const, smul_eq_mul, mul_zero, integral_zero] #align probability_theory.moment_zero ProbabilityTheory.moment_zero @[simp] theorem centralMoment_zero (hp : p ≠ 0) : centralMoment 0 p μ = 0 := by simp only [centralMoment, hp, Pi.zero_apply, integral_const, smul_eq_mul, mul_zero, zero_sub, Pi.pow_apply, Pi.neg_apply, neg_zero, zero_pow, Ne, not_false_iff] #align probability_theory.central_moment_zero ProbabilityTheory.centralMoment_zero theorem centralMoment_one' [IsFiniteMeasure μ] (h_int : Integrable X μ) : centralMoment X 1 μ = (1 - (μ Set.univ).toReal) * μ[X] := by simp only [centralMoment, Pi.sub_apply, pow_one] rw [integral_sub h_int (integrable_const _)] simp only [sub_mul, integral_const, smul_eq_mul, one_mul] #align probability_theory.central_moment_one' ProbabilityTheory.centralMoment_one' @[simp] theorem centralMoment_one [IsProbabilityMeasure μ] : centralMoment X 1 μ = 0 := by by_cases h_int : Integrable X μ · rw [centralMoment_one' h_int] simp only [measure_univ, ENNReal.one_toReal, sub_self, zero_mul] · simp only [centralMoment, Pi.sub_apply, pow_one] have : ¬Integrable (fun x => X x - integral μ X) μ := by refine fun h_sub => h_int ?_ have h_add : X = (fun x => X x - integral μ X) + fun _ => integral μ X := by ext1 x; simp rw [h_add] exact h_sub.add (integrable_const _) rw [integral_undef this] #align probability_theory.central_moment_one ProbabilityTheory.centralMoment_one theorem centralMoment_two_eq_variance [IsFiniteMeasure μ] (hX : Memℒp X 2 μ) : centralMoment X 2 μ = variance X μ := by rw [hX.variance_eq]; rfl #align probability_theory.central_moment_two_eq_variance ProbabilityTheory.centralMoment_two_eq_variance section MomentGeneratingFunction variable {t : ℝ} def mgf (X : Ω → ℝ) (μ : Measure Ω) (t : ℝ) : ℝ := μ[fun ω => exp (t * X ω)] #align probability_theory.mgf ProbabilityTheory.mgf def cgf (X : Ω → ℝ) (μ : Measure Ω) (t : ℝ) : ℝ := log (mgf X μ t) #align probability_theory.cgf ProbabilityTheory.cgf @[simp] theorem mgf_zero_fun : mgf 0 μ t = (μ Set.univ).toReal := by simp only [mgf, Pi.zero_apply, mul_zero, exp_zero, integral_const, smul_eq_mul, mul_one] #align probability_theory.mgf_zero_fun ProbabilityTheory.mgf_zero_fun @[simp] theorem cgf_zero_fun : cgf 0 μ t = log (μ Set.univ).toReal := by simp only [cgf, mgf_zero_fun] #align probability_theory.cgf_zero_fun ProbabilityTheory.cgf_zero_fun @[simp] theorem mgf_zero_measure : mgf X (0 : Measure Ω) t = 0 := by simp only [mgf, integral_zero_measure] #align probability_theory.mgf_zero_measure ProbabilityTheory.mgf_zero_measure @[simp] theorem cgf_zero_measure : cgf X (0 : Measure Ω) t = 0 := by simp only [cgf, log_zero, mgf_zero_measure] #align probability_theory.cgf_zero_measure ProbabilityTheory.cgf_zero_measure @[simp] theorem mgf_const' (c : ℝ) : mgf (fun _ => c) μ t = (μ Set.univ).toReal * exp (t * c) := by simp only [mgf, integral_const, smul_eq_mul] #align probability_theory.mgf_const' ProbabilityTheory.mgf_const' -- @[simp] -- Porting note: `simp only` already proves this
Mathlib/Probability/Moments.lean
136
137
theorem mgf_const (c : ℝ) [IsProbabilityMeasure μ] : mgf (fun _ => c) μ t = exp (t * c) := by
simp only [mgf_const', measure_univ, ENNReal.one_toReal, one_mul]
import Mathlib.Tactic.CategoryTheory.Coherence import Mathlib.CategoryTheory.Monoidal.Free.Coherence #align_import category_theory.monoidal.coherence_lemmas from "leanprover-community/mathlib"@"b8b8bf3ea0c625fa1f950034a184e07c67f7bcfe" open CategoryTheory Category Iso namespace CategoryTheory.MonoidalCategory variable {C : Type*} [Category C] [MonoidalCategory C] -- See Proposition 2.2.4 of <http://www-math.mit.edu/~etingof/egnobookfinal.pdf> @[reassoc] theorem leftUnitor_tensor'' (X Y : C) : (α_ (𝟙_ C) X Y).hom ≫ (λ_ (X ⊗ Y)).hom = (λ_ X).hom ⊗ 𝟙 Y := by coherence #align category_theory.monoidal_category.left_unitor_tensor' CategoryTheory.MonoidalCategory.leftUnitor_tensor'' @[reassoc] theorem leftUnitor_tensor' (X Y : C) : (λ_ (X ⊗ Y)).hom = (α_ (𝟙_ C) X Y).inv ≫ ((λ_ X).hom ⊗ 𝟙 Y) := by coherence #align category_theory.monoidal_category.left_unitor_tensor CategoryTheory.MonoidalCategory.leftUnitor_tensor' @[reassoc] theorem leftUnitor_tensor_inv' (X Y : C) : (λ_ (X ⊗ Y)).inv = ((λ_ X).inv ⊗ 𝟙 Y) ≫ (α_ (𝟙_ C) X Y).hom := by coherence #align category_theory.monoidal_category.left_unitor_tensor_inv CategoryTheory.MonoidalCategory.leftUnitor_tensor_inv' @[reassoc] theorem id_tensor_rightUnitor_inv (X Y : C) : 𝟙 X ⊗ (ρ_ Y).inv = (ρ_ _).inv ≫ (α_ _ _ _).hom := by coherence #align category_theory.monoidal_category.id_tensor_right_unitor_inv CategoryTheory.MonoidalCategory.id_tensor_rightUnitor_inv @[reassoc] theorem leftUnitor_inv_tensor_id (X Y : C) : (λ_ X).inv ⊗ 𝟙 Y = (λ_ _).inv ≫ (α_ _ _ _).inv := by coherence #align category_theory.monoidal_category.left_unitor_inv_tensor_id CategoryTheory.MonoidalCategory.leftUnitor_inv_tensor_id @[reassoc] theorem pentagon_inv_inv_hom (W X Y Z : C) : (α_ W (X ⊗ Y) Z).inv ≫ ((α_ W X Y).inv ⊗ 𝟙 Z) ≫ (α_ (W ⊗ X) Y Z).hom = (𝟙 W ⊗ (α_ X Y Z).hom) ≫ (α_ W X (Y ⊗ Z)).inv := by coherence #align category_theory.monoidal_category.pentagon_inv_inv_hom CategoryTheory.MonoidalCategory.pentagon_inv_inv_hom theorem unitors_equal : (λ_ (𝟙_ C)).hom = (ρ_ (𝟙_ C)).hom := by coherence #align category_theory.monoidal_category.unitors_equal CategoryTheory.MonoidalCategory.unitors_equal
Mathlib/CategoryTheory/Monoidal/CoherenceLemmas.lean
67
68
theorem unitors_inv_equal : (λ_ (𝟙_ C)).inv = (ρ_ (𝟙_ C)).inv := by
coherence
import Mathlib.Algebra.Polynomial.Degree.Definitions import Mathlib.Data.ENat.Basic #align_import data.polynomial.degree.trailing_degree from "leanprover-community/mathlib"@"302eab4f46abb63de520828de78c04cb0f9b5836" noncomputable section open Function Polynomial Finsupp Finset open scoped Polynomial namespace Polynomial universe u v variable {R : Type u} {S : Type v} {a b : R} {n m : ℕ} section Semiring variable [Semiring R] {p q r : R[X]} def trailingDegree (p : R[X]) : ℕ∞ := p.support.min #align polynomial.trailing_degree Polynomial.trailingDegree theorem trailingDegree_lt_wf : WellFounded fun p q : R[X] => trailingDegree p < trailingDegree q := InvImage.wf trailingDegree wellFounded_lt #align polynomial.trailing_degree_lt_wf Polynomial.trailingDegree_lt_wf def natTrailingDegree (p : R[X]) : ℕ := (trailingDegree p).getD 0 #align polynomial.nat_trailing_degree Polynomial.natTrailingDegree def trailingCoeff (p : R[X]) : R := coeff p (natTrailingDegree p) #align polynomial.trailing_coeff Polynomial.trailingCoeff def TrailingMonic (p : R[X]) := trailingCoeff p = (1 : R) #align polynomial.trailing_monic Polynomial.TrailingMonic theorem TrailingMonic.def : TrailingMonic p ↔ trailingCoeff p = 1 := Iff.rfl #align polynomial.trailing_monic.def Polynomial.TrailingMonic.def instance TrailingMonic.decidable [DecidableEq R] : Decidable (TrailingMonic p) := inferInstanceAs <| Decidable (trailingCoeff p = (1 : R)) #align polynomial.trailing_monic.decidable Polynomial.TrailingMonic.decidable @[simp] theorem TrailingMonic.trailingCoeff {p : R[X]} (hp : p.TrailingMonic) : trailingCoeff p = 1 := hp #align polynomial.trailing_monic.trailing_coeff Polynomial.TrailingMonic.trailingCoeff @[simp] theorem trailingDegree_zero : trailingDegree (0 : R[X]) = ⊤ := rfl #align polynomial.trailing_degree_zero Polynomial.trailingDegree_zero @[simp] theorem trailingCoeff_zero : trailingCoeff (0 : R[X]) = 0 := rfl #align polynomial.trailing_coeff_zero Polynomial.trailingCoeff_zero @[simp] theorem natTrailingDegree_zero : natTrailingDegree (0 : R[X]) = 0 := rfl #align polynomial.nat_trailing_degree_zero Polynomial.natTrailingDegree_zero theorem trailingDegree_eq_top : trailingDegree p = ⊤ ↔ p = 0 := ⟨fun h => support_eq_empty.1 (Finset.min_eq_top.1 h), fun h => by simp [h]⟩ #align polynomial.trailing_degree_eq_top Polynomial.trailingDegree_eq_top theorem trailingDegree_eq_natTrailingDegree (hp : p ≠ 0) : trailingDegree p = (natTrailingDegree p : ℕ∞) := by let ⟨n, hn⟩ := not_forall.1 (mt Option.eq_none_iff_forall_not_mem.2 (mt trailingDegree_eq_top.1 hp)) have hn : trailingDegree p = n := Classical.not_not.1 hn rw [natTrailingDegree, hn] rfl #align polynomial.trailing_degree_eq_nat_trailing_degree Polynomial.trailingDegree_eq_natTrailingDegree
Mathlib/Algebra/Polynomial/Degree/TrailingDegree.lean
111
114
theorem trailingDegree_eq_iff_natTrailingDegree_eq {p : R[X]} {n : ℕ} (hp : p ≠ 0) : p.trailingDegree = n ↔ p.natTrailingDegree = n := by
rw [trailingDegree_eq_natTrailingDegree hp] exact WithTop.coe_eq_coe
import Mathlib.Topology.Bases import Mathlib.Topology.DenseEmbedding #align_import topology.stone_cech from "leanprover-community/mathlib"@"0a0ec35061ed9960bf0e7ffb0335f44447b58977" noncomputable section open Filter Set open Topology universe u v section Ultrafilter def ultrafilterBasis (α : Type u) : Set (Set (Ultrafilter α)) := range fun s : Set α => { u | s ∈ u } #align ultrafilter_basis ultrafilterBasis variable {α : Type u} instance Ultrafilter.topologicalSpace : TopologicalSpace (Ultrafilter α) := TopologicalSpace.generateFrom (ultrafilterBasis α) #align ultrafilter.topological_space Ultrafilter.topologicalSpace theorem ultrafilterBasis_is_basis : TopologicalSpace.IsTopologicalBasis (ultrafilterBasis α) := ⟨by rintro _ ⟨a, rfl⟩ _ ⟨b, rfl⟩ u ⟨ua, ub⟩ refine ⟨_, ⟨a ∩ b, rfl⟩, inter_mem ua ub, fun v hv => ⟨?_, ?_⟩⟩ <;> apply mem_of_superset hv <;> simp [inter_subset_right], eq_univ_of_univ_subset <| subset_sUnion_of_mem <| ⟨univ, eq_univ_of_forall fun u => univ_mem⟩, rfl⟩ #align ultrafilter_basis_is_basis ultrafilterBasis_is_basis theorem ultrafilter_isOpen_basic (s : Set α) : IsOpen { u : Ultrafilter α | s ∈ u } := ultrafilterBasis_is_basis.isOpen ⟨s, rfl⟩ #align ultrafilter_is_open_basic ultrafilter_isOpen_basic theorem ultrafilter_isClosed_basic (s : Set α) : IsClosed { u : Ultrafilter α | s ∈ u } := by rw [← isOpen_compl_iff] convert ultrafilter_isOpen_basic sᶜ using 1 ext u exact Ultrafilter.compl_mem_iff_not_mem.symm #align ultrafilter_is_closed_basic ultrafilter_isClosed_basic
Mathlib/Topology/StoneCech.lean
67
77
theorem ultrafilter_converges_iff {u : Ultrafilter (Ultrafilter α)} {x : Ultrafilter α} : ↑u ≤ 𝓝 x ↔ x = joinM u := by
rw [eq_comm, ← Ultrafilter.coe_le_coe] change ↑u ≤ 𝓝 x ↔ ∀ s ∈ x, { v : Ultrafilter α | s ∈ v } ∈ u simp only [TopologicalSpace.nhds_generateFrom, le_iInf_iff, ultrafilterBasis, le_principal_iff, mem_setOf_eq] constructor · intro h a ha exact h _ ⟨ha, a, rfl⟩ · rintro h a ⟨xi, a, rfl⟩ exact h _ xi
import Mathlib.Analysis.InnerProductSpace.Basic import Mathlib.MeasureTheory.Constructions.BorelSpace.Complex #align_import measure_theory.function.special_functions.inner from "leanprover-community/mathlib"@"bf6a01357ff5684b1ebcd0f1a13be314fc82c0bf" variable {α : Type*} {𝕜 : Type*} {E : Type*} variable [RCLike 𝕜] [NormedAddCommGroup E] [InnerProductSpace 𝕜 E] local notation "⟪" x ", " y "⟫" => @inner 𝕜 _ _ x y @[aesop safe 20 apply (rule_sets := [Measurable])] theorem Measurable.inner {_ : MeasurableSpace α} [MeasurableSpace E] [OpensMeasurableSpace E] [SecondCountableTopology E] {f g : α → E} (hf : Measurable f) (hg : Measurable g) : Measurable fun t => ⟪f t, g t⟫ := Continuous.measurable2 continuous_inner hf hg #align measurable.inner Measurable.inner @[measurability] theorem Measurable.const_inner {_ : MeasurableSpace α} [MeasurableSpace E] [OpensMeasurableSpace E] [SecondCountableTopology E] {c : E} {f : α → E} (hf : Measurable f) : Measurable fun t => ⟪c, f t⟫ := Measurable.inner measurable_const hf @[measurability] theorem Measurable.inner_const {_ : MeasurableSpace α} [MeasurableSpace E] [OpensMeasurableSpace E] [SecondCountableTopology E] {c : E} {f : α → E} (hf : Measurable f) : Measurable fun t => ⟪f t, c⟫ := Measurable.inner hf measurable_const @[aesop safe 20 apply (rule_sets := [Measurable])]
Mathlib/MeasureTheory/Function/SpecialFunctions/Inner.lean
41
47
theorem AEMeasurable.inner {m : MeasurableSpace α} [MeasurableSpace E] [OpensMeasurableSpace E] [SecondCountableTopology E] {μ : MeasureTheory.Measure α} {f g : α → E} (hf : AEMeasurable f μ) (hg : AEMeasurable g μ) : AEMeasurable (fun x => ⟪f x, g x⟫) μ := by
refine ⟨fun x => ⟪hf.mk f x, hg.mk g x⟫, hf.measurable_mk.inner hg.measurable_mk, ?_⟩ refine hf.ae_eq_mk.mp (hg.ae_eq_mk.mono fun x hxg hxf => ?_) dsimp only congr
import Mathlib.Algebra.Order.Ring.Abs import Mathlib.Tactic.Ring #align_import data.nat.hyperoperation from "leanprover-community/mathlib"@"f7fc89d5d5ff1db2d1242c7bb0e9062ce47ef47c" def hyperoperation : ℕ → ℕ → ℕ → ℕ | 0, _, k => k + 1 | 1, m, 0 => m | 2, _, 0 => 0 | _ + 3, _, 0 => 1 | n + 1, m, k + 1 => hyperoperation n m (hyperoperation (n + 1) m k) #align hyperoperation hyperoperation -- Basic hyperoperation lemmas @[simp] theorem hyperoperation_zero (m : ℕ) : hyperoperation 0 m = Nat.succ := funext fun k => by rw [hyperoperation, Nat.succ_eq_add_one] #align hyperoperation_zero hyperoperation_zero theorem hyperoperation_ge_three_eq_one (n m : ℕ) : hyperoperation (n + 3) m 0 = 1 := by rw [hyperoperation] #align hyperoperation_ge_three_eq_one hyperoperation_ge_three_eq_one theorem hyperoperation_recursion (n m k : ℕ) : hyperoperation (n + 1) m (k + 1) = hyperoperation n m (hyperoperation (n + 1) m k) := by rw [hyperoperation] #align hyperoperation_recursion hyperoperation_recursion -- Interesting hyperoperation lemmas @[simp] theorem hyperoperation_one : hyperoperation 1 = (· + ·) := by ext m k induction' k with bn bih · rw [Nat.add_zero m, hyperoperation] · rw [hyperoperation_recursion, bih, hyperoperation_zero] exact Nat.add_assoc m bn 1 #align hyperoperation_one hyperoperation_one @[simp]
Mathlib/Data/Nat/Hyperoperation.lean
69
78
theorem hyperoperation_two : hyperoperation 2 = (· * ·) := by
ext m k induction' k with bn bih · rw [hyperoperation] exact (Nat.mul_zero m).symm · rw [hyperoperation_recursion, hyperoperation_one, bih] -- Porting note: was `ring` dsimp only nth_rewrite 1 [← mul_one m] rw [← mul_add, add_comm]
import Mathlib.Data.Fintype.Basic import Mathlib.ModelTheory.Substructures #align_import model_theory.elementary_maps from "leanprover-community/mathlib"@"d11893b411025250c8e61ff2f12ccbd7ee35ab15" open FirstOrder namespace FirstOrder namespace Language open Structure variable (L : Language) (M : Type*) (N : Type*) {P : Type*} {Q : Type*} variable [L.Structure M] [L.Structure N] [L.Structure P] [L.Structure Q] structure ElementaryEmbedding where toFun : M → N -- Porting note: -- The autoparam here used to be `obviously`. We would like to replace it with `aesop` -- but that isn't currently sufficient. -- See https://leanprover.zulipchat.com/#narrow/stream/287929-mathlib4/topic/Aesop.20and.20cases -- If that can be improved, we should change this to `by aesop` and remove the proofs below. map_formula' : ∀ ⦃n⦄ (φ : L.Formula (Fin n)) (x : Fin n → M), φ.Realize (toFun ∘ x) ↔ φ.Realize x := by intros; trivial #align first_order.language.elementary_embedding FirstOrder.Language.ElementaryEmbedding #align first_order.language.elementary_embedding.to_fun FirstOrder.Language.ElementaryEmbedding.toFun #align first_order.language.elementary_embedding.map_formula' FirstOrder.Language.ElementaryEmbedding.map_formula' @[inherit_doc FirstOrder.Language.ElementaryEmbedding] scoped[FirstOrder] notation:25 A " ↪ₑ[" L "] " B => FirstOrder.Language.ElementaryEmbedding L A B variable {L} {M} {N} namespace ElementaryEmbedding attribute [coe] toFun instance instFunLike : FunLike (M ↪ₑ[L] N) M N where coe f := f.toFun coe_injective' f g h := by cases f cases g simp only [ElementaryEmbedding.mk.injEq] ext x exact Function.funext_iff.1 h x #align first_order.language.elementary_embedding.fun_like FirstOrder.Language.ElementaryEmbedding.instFunLike instance : CoeFun (M ↪ₑ[L] N) fun _ => M → N := DFunLike.hasCoeToFun @[simp]
Mathlib/ModelTheory/ElementaryMaps.lean
78
94
theorem map_boundedFormula (f : M ↪ₑ[L] N) {α : Type*} {n : ℕ} (φ : L.BoundedFormula α n) (v : α → M) (xs : Fin n → M) : φ.Realize (f ∘ v) (f ∘ xs) ↔ φ.Realize v xs := by
classical rw [← BoundedFormula.realize_restrictFreeVar Set.Subset.rfl, Set.inclusion_eq_id, iff_eq_eq] have h := f.map_formula' ((φ.restrictFreeVar id).toFormula.relabel (Fintype.equivFin _)) (Sum.elim (v ∘ (↑)) xs ∘ (Fintype.equivFin _).symm) simp only [Formula.realize_relabel, BoundedFormula.realize_toFormula, iff_eq_eq] at h rw [← Function.comp.assoc _ _ (Fintype.equivFin _).symm, Function.comp.assoc _ (Fintype.equivFin _).symm (Fintype.equivFin _), _root_.Equiv.symm_comp_self, Function.comp_id, Function.comp.assoc, Sum.elim_comp_inl, Function.comp.assoc _ _ Sum.inr, Sum.elim_comp_inr, ← Function.comp.assoc] at h refine h.trans ?_ erw [Function.comp.assoc _ _ (Fintype.equivFin _), _root_.Equiv.symm_comp_self, Function.comp_id, Sum.elim_comp_inl, Sum.elim_comp_inr (v ∘ Subtype.val) xs, ← Set.inclusion_eq_id (s := (BoundedFormula.freeVarFinset φ : Set α)) Set.Subset.rfl, BoundedFormula.realize_restrictFreeVar Set.Subset.rfl]
import Mathlib.FieldTheory.PurelyInseparable import Mathlib.FieldTheory.PerfectClosure open scoped Classical Polynomial open FiniteDimensional Polynomial IntermediateField Field noncomputable section def pNilradical (R : Type*) [CommSemiring R] (p : ℕ) : Ideal R := if 1 < p then nilradical R else ⊥ theorem pNilradical_le_nilradical {R : Type*} [CommSemiring R] {p : ℕ} : pNilradical R p ≤ nilradical R := by by_cases hp : 1 < p · rw [pNilradical, if_pos hp] simp_rw [pNilradical, if_neg hp, bot_le]
Mathlib/FieldTheory/IsPerfectClosure.lean
81
82
theorem pNilradical_eq_nilradical {R : Type*} [CommSemiring R] {p : ℕ} (hp : 1 < p) : pNilradical R p = nilradical R := by
rw [pNilradical, if_pos hp]
import Mathlib.Algebra.CharP.Invertible import Mathlib.Algebra.Order.Interval.Set.Group import Mathlib.Analysis.Convex.Segment import Mathlib.LinearAlgebra.AffineSpace.FiniteDimensional import Mathlib.Tactic.FieldSimp #align_import analysis.convex.between from "leanprover-community/mathlib"@"571e13cacbed7bf042fd3058ce27157101433842" variable (R : Type*) {V V' P P' : Type*} open AffineEquiv AffineMap section OrderedRing variable [OrderedRing R] [AddCommGroup V] [Module R V] [AddTorsor V P] variable [AddCommGroup V'] [Module R V'] [AddTorsor V' P'] def affineSegment (x y : P) := lineMap x y '' Set.Icc (0 : R) 1 #align affine_segment affineSegment theorem affineSegment_eq_segment (x y : V) : affineSegment R x y = segment R x y := by rw [segment_eq_image_lineMap, affineSegment] #align affine_segment_eq_segment affineSegment_eq_segment theorem affineSegment_comm (x y : P) : affineSegment R x y = affineSegment R y x := by refine Set.ext fun z => ?_ constructor <;> · rintro ⟨t, ht, hxy⟩ refine ⟨1 - t, ?_, ?_⟩ · rwa [Set.sub_mem_Icc_iff_right, sub_self, sub_zero] · rwa [lineMap_apply_one_sub] #align affine_segment_comm affineSegment_comm theorem left_mem_affineSegment (x y : P) : x ∈ affineSegment R x y := ⟨0, Set.left_mem_Icc.2 zero_le_one, lineMap_apply_zero _ _⟩ #align left_mem_affine_segment left_mem_affineSegment theorem right_mem_affineSegment (x y : P) : y ∈ affineSegment R x y := ⟨1, Set.right_mem_Icc.2 zero_le_one, lineMap_apply_one _ _⟩ #align right_mem_affine_segment right_mem_affineSegment @[simp] theorem affineSegment_same (x : P) : affineSegment R x x = {x} := by -- Porting note: added as this doesn't do anything in `simp_rw` any more rw [affineSegment] -- Note: when adding "simp made no progress" in lean4#2336, -- had to change `lineMap_same` to `lineMap_same _`. Not sure why? -- Porting note: added `_ _` and `Function.const` simp_rw [lineMap_same _, AffineMap.coe_const _ _, Function.const, (Set.nonempty_Icc.mpr zero_le_one).image_const] #align affine_segment_same affineSegment_same variable {R} @[simp]
Mathlib/Analysis/Convex/Between.lean
80
83
theorem affineSegment_image (f : P →ᵃ[R] P') (x y : P) : f '' affineSegment R x y = affineSegment R (f x) (f y) := by
rw [affineSegment, affineSegment, Set.image_image, ← comp_lineMap] rfl
import Mathlib.Algebra.BigOperators.Fin import Mathlib.Algebra.BigOperators.NatAntidiagonal import Mathlib.Algebra.CharZero.Lemmas import Mathlib.Data.Finset.NatAntidiagonal import Mathlib.Data.Nat.Choose.Central import Mathlib.Data.Tree.Basic import Mathlib.Tactic.FieldSimp import Mathlib.Tactic.GCongr import Mathlib.Tactic.Positivity #align_import combinatorics.catalan from "leanprover-community/mathlib"@"26b40791e4a5772a4e53d0e28e4df092119dc7da" open Finset open Finset.antidiagonal (fst_le snd_le) def catalan : ℕ → ℕ | 0 => 1 | n + 1 => ∑ i : Fin n.succ, catalan i * catalan (n - i) #align catalan catalan @[simp] theorem catalan_zero : catalan 0 = 1 := by rw [catalan] #align catalan_zero catalan_zero theorem catalan_succ (n : ℕ) : catalan (n + 1) = ∑ i : Fin n.succ, catalan i * catalan (n - i) := by rw [catalan] #align catalan_succ catalan_succ theorem catalan_succ' (n : ℕ) : catalan (n + 1) = ∑ ij ∈ antidiagonal n, catalan ij.1 * catalan ij.2 := by rw [catalan_succ, Nat.sum_antidiagonal_eq_sum_range_succ (fun x y => catalan x * catalan y) n, sum_range] #align catalan_succ' catalan_succ' @[simp] theorem catalan_one : catalan 1 = 1 := by simp [catalan_succ] #align catalan_one catalan_one private def gosperCatalan (n j : ℕ) : ℚ := Nat.centralBinom j * Nat.centralBinom (n - j) * (2 * j - n) / (2 * n * (n + 1)) private theorem gosper_trick {n i : ℕ} (h : i ≤ n) : gosperCatalan (n + 1) (i + 1) - gosperCatalan (n + 1) i = Nat.centralBinom i / (i + 1) * Nat.centralBinom (n - i) / (n - i + 1) := by have l₁ : (i : ℚ) + 1 ≠ 0 := by norm_cast have l₂ : (n : ℚ) - i + 1 ≠ 0 := by norm_cast have h₁ := (mul_div_cancel_left₀ (↑(Nat.centralBinom (i + 1))) l₁).symm have h₂ := (mul_div_cancel_left₀ (↑(Nat.centralBinom (n - i + 1))) l₂).symm have h₃ : ((i : ℚ) + 1) * (i + 1).centralBinom = 2 * (2 * i + 1) * i.centralBinom := mod_cast Nat.succ_mul_centralBinom_succ i have h₄ : ((n : ℚ) - i + 1) * (n - i + 1).centralBinom = 2 * (2 * (n - i) + 1) * (n - i).centralBinom := mod_cast Nat.succ_mul_centralBinom_succ (n - i) simp only [gosperCatalan] push_cast rw [show n + 1 - i = n - i + 1 by rw [Nat.add_comm (n - i) 1, ← (Nat.add_sub_assoc h 1), add_comm]] rw [h₁, h₂, h₃, h₄] field_simp ring private theorem gosper_catalan_sub_eq_central_binom_div (n : ℕ) : gosperCatalan (n + 1) (n + 1) - gosperCatalan (n + 1) 0 = Nat.centralBinom (n + 1) / (n + 2) := by have : (n : ℚ) + 1 ≠ 0 := by norm_cast have : (n : ℚ) + 1 + 1 ≠ 0 := by norm_cast have h : (n : ℚ) + 2 ≠ 0 := by norm_cast simp only [gosperCatalan, Nat.sub_zero, Nat.centralBinom_zero, Nat.sub_self] field_simp ring theorem catalan_eq_centralBinom_div (n : ℕ) : catalan n = n.centralBinom / (n + 1) := by suffices (catalan n : ℚ) = Nat.centralBinom n / (n + 1) by have h := Nat.succ_dvd_centralBinom n exact mod_cast this induction' n using Nat.case_strong_induction_on with d hd · simp · simp_rw [catalan_succ, Nat.cast_sum, Nat.cast_mul] trans (∑ i : Fin d.succ, Nat.centralBinom i / (i + 1) * (Nat.centralBinom (d - i) / (d - i + 1)) : ℚ) · congr ext1 x have m_le_d : x.val ≤ d := by apply Nat.le_of_lt_succ; apply x.2 have d_minus_x_le_d : (d - x.val) ≤ d := tsub_le_self rw [hd _ m_le_d, hd _ d_minus_x_le_d] norm_cast · trans (∑ i : Fin d.succ, (gosperCatalan (d + 1) (i + 1) - gosperCatalan (d + 1) i)) · refine sum_congr rfl fun i _ => ?_ rw [gosper_trick i.is_le, mul_div] · rw [← sum_range fun i => gosperCatalan (d + 1) (i + 1) - gosperCatalan (d + 1) i, sum_range_sub, Nat.succ_eq_add_one] rw [gosper_catalan_sub_eq_central_binom_div d] norm_cast #align catalan_eq_central_binom_div catalan_eq_centralBinom_div theorem succ_mul_catalan_eq_centralBinom (n : ℕ) : (n + 1) * catalan n = n.centralBinom := (Nat.eq_mul_of_div_eq_right n.succ_dvd_centralBinom (catalan_eq_centralBinom_div n).symm).symm #align succ_mul_catalan_eq_central_binom succ_mul_catalan_eq_centralBinom theorem catalan_two : catalan 2 = 2 := by norm_num [catalan_eq_centralBinom_div, Nat.centralBinom, Nat.choose] #align catalan_two catalan_two
Mathlib/Combinatorics/Enumerative/Catalan.lean
148
149
theorem catalan_three : catalan 3 = 5 := by
norm_num [catalan_eq_centralBinom_div, Nat.centralBinom, Nat.choose]
import Mathlib.Algebra.FreeMonoid.Basic import Mathlib.Algebra.Group.Submonoid.MulOpposite import Mathlib.Algebra.Group.Submonoid.Operations import Mathlib.Algebra.GroupWithZero.Divisibility import Mathlib.Data.Finset.NoncommProd import Mathlib.Data.Int.Order.Lemmas #align_import group_theory.submonoid.membership from "leanprover-community/mathlib"@"e655e4ea5c6d02854696f97494997ba4c31be802" variable {M A B : Type*} section Assoc variable [Monoid M] [SetLike B M] [SubmonoidClass B M] {S : B} section NonAssoc variable [MulOneClass M] open Set namespace Submonoid -- TODO: this section can be generalized to `[SubmonoidClass B M] [CompleteLattice B]` -- such that `CompleteLattice.LE` coincides with `SetLike.LE` @[to_additive] theorem mem_iSup_of_directed {ι} [hι : Nonempty ι] {S : ι → Submonoid M} (hS : Directed (· ≤ ·) S) {x : M} : (x ∈ ⨆ i, S i) ↔ ∃ i, x ∈ S i := by refine ⟨?_, fun ⟨i, hi⟩ ↦ le_iSup S i hi⟩ suffices x ∈ closure (⋃ i, (S i : Set M)) → ∃ i, x ∈ S i by simpa only [closure_iUnion, closure_eq (S _)] using this refine fun hx ↦ closure_induction hx (fun _ ↦ mem_iUnion.1) ?_ ?_ · exact hι.elim fun i ↦ ⟨i, (S i).one_mem⟩ · rintro x y ⟨i, hi⟩ ⟨j, hj⟩ rcases hS i j with ⟨k, hki, hkj⟩ exact ⟨k, (S k).mul_mem (hki hi) (hkj hj)⟩ #align submonoid.mem_supr_of_directed Submonoid.mem_iSup_of_directed #align add_submonoid.mem_supr_of_directed AddSubmonoid.mem_iSup_of_directed @[to_additive] theorem coe_iSup_of_directed {ι} [Nonempty ι] {S : ι → Submonoid M} (hS : Directed (· ≤ ·) S) : ((⨆ i, S i : Submonoid M) : Set M) = ⋃ i, S i := Set.ext fun x ↦ by simp [mem_iSup_of_directed hS] #align submonoid.coe_supr_of_directed Submonoid.coe_iSup_of_directed #align add_submonoid.coe_supr_of_directed AddSubmonoid.coe_iSup_of_directed @[to_additive] theorem mem_sSup_of_directedOn {S : Set (Submonoid M)} (Sne : S.Nonempty) (hS : DirectedOn (· ≤ ·) S) {x : M} : x ∈ sSup S ↔ ∃ s ∈ S, x ∈ s := by haveI : Nonempty S := Sne.to_subtype simp [sSup_eq_iSup', mem_iSup_of_directed hS.directed_val, SetCoe.exists, Subtype.coe_mk] #align submonoid.mem_Sup_of_directed_on Submonoid.mem_sSup_of_directedOn #align add_submonoid.mem_Sup_of_directed_on AddSubmonoid.mem_sSup_of_directedOn @[to_additive] theorem coe_sSup_of_directedOn {S : Set (Submonoid M)} (Sne : S.Nonempty) (hS : DirectedOn (· ≤ ·) S) : (↑(sSup S) : Set M) = ⋃ s ∈ S, ↑s := Set.ext fun x => by simp [mem_sSup_of_directedOn Sne hS] #align submonoid.coe_Sup_of_directed_on Submonoid.coe_sSup_of_directedOn #align add_submonoid.coe_Sup_of_directed_on AddSubmonoid.coe_sSup_of_directedOn @[to_additive] theorem mem_sup_left {S T : Submonoid M} : ∀ {x : M}, x ∈ S → x ∈ S ⊔ T := by rw [← SetLike.le_def] exact le_sup_left #align submonoid.mem_sup_left Submonoid.mem_sup_left #align add_submonoid.mem_sup_left AddSubmonoid.mem_sup_left @[to_additive] theorem mem_sup_right {S T : Submonoid M} : ∀ {x : M}, x ∈ T → x ∈ S ⊔ T := by rw [← SetLike.le_def] exact le_sup_right #align submonoid.mem_sup_right Submonoid.mem_sup_right #align add_submonoid.mem_sup_right AddSubmonoid.mem_sup_right @[to_additive] theorem mul_mem_sup {S T : Submonoid M} {x y : M} (hx : x ∈ S) (hy : y ∈ T) : x * y ∈ S ⊔ T := (S ⊔ T).mul_mem (mem_sup_left hx) (mem_sup_right hy) #align submonoid.mul_mem_sup Submonoid.mul_mem_sup #align add_submonoid.add_mem_sup AddSubmonoid.add_mem_sup @[to_additive] theorem mem_iSup_of_mem {ι : Sort*} {S : ι → Submonoid M} (i : ι) : ∀ {x : M}, x ∈ S i → x ∈ iSup S := by rw [← SetLike.le_def] exact le_iSup _ _ #align submonoid.mem_supr_of_mem Submonoid.mem_iSup_of_mem #align add_submonoid.mem_supr_of_mem AddSubmonoid.mem_iSup_of_mem @[to_additive]
Mathlib/Algebra/Group/Submonoid/Membership.lean
262
265
theorem mem_sSup_of_mem {S : Set (Submonoid M)} {s : Submonoid M} (hs : s ∈ S) : ∀ {x : M}, x ∈ s → x ∈ sSup S := by
rw [← SetLike.le_def] exact le_sSup hs
import Mathlib.Data.List.Cycle import Mathlib.GroupTheory.Perm.Cycle.Type import Mathlib.GroupTheory.Perm.List #align_import group_theory.perm.cycle.concrete from "leanprover-community/mathlib"@"00638177efd1b2534fc5269363ebf42a7871df9a" open Equiv Equiv.Perm List variable {α : Type*} namespace Equiv.Perm section Fintype variable [Fintype α] [DecidableEq α] (p : Equiv.Perm α) (x : α) def toList : List α := (List.range (cycleOf p x).support.card).map fun k => (p ^ k) x #align equiv.perm.to_list Equiv.Perm.toList @[simp] theorem toList_one : toList (1 : Perm α) x = [] := by simp [toList, cycleOf_one] #align equiv.perm.to_list_one Equiv.Perm.toList_one @[simp] theorem toList_eq_nil_iff {p : Perm α} {x} : toList p x = [] ↔ x ∉ p.support := by simp [toList] #align equiv.perm.to_list_eq_nil_iff Equiv.Perm.toList_eq_nil_iff @[simp] theorem length_toList : length (toList p x) = (cycleOf p x).support.card := by simp [toList] #align equiv.perm.length_to_list Equiv.Perm.length_toList theorem toList_ne_singleton (y : α) : toList p x ≠ [y] := by intro H simpa [card_support_ne_one] using congr_arg length H #align equiv.perm.to_list_ne_singleton Equiv.Perm.toList_ne_singleton theorem two_le_length_toList_iff_mem_support {p : Perm α} {x : α} : 2 ≤ length (toList p x) ↔ x ∈ p.support := by simp #align equiv.perm.two_le_length_to_list_iff_mem_support Equiv.Perm.two_le_length_toList_iff_mem_support theorem length_toList_pos_of_mem_support (h : x ∈ p.support) : 0 < length (toList p x) := zero_lt_two.trans_le (two_le_length_toList_iff_mem_support.mpr h) #align equiv.perm.length_to_list_pos_of_mem_support Equiv.Perm.length_toList_pos_of_mem_support theorem get_toList (n : ℕ) (hn : n < length (toList p x)) : (toList p x).get ⟨n, hn⟩ = (p ^ n) x := by simp [toList] theorem toList_get_zero (h : x ∈ p.support) : (toList p x).get ⟨0, (length_toList_pos_of_mem_support _ _ h)⟩ = x := by simp [toList] set_option linter.deprecated false in @[deprecated get_toList (since := "2024-05-08")] theorem nthLe_toList (n : ℕ) (hn : n < length (toList p x)) : (toList p x).nthLe n hn = (p ^ n) x := by simp [toList] #align equiv.perm.nth_le_to_list Equiv.Perm.nthLe_toList set_option linter.deprecated false in @[deprecated toList_get_zero (since := "2024-05-08")] theorem toList_nthLe_zero (h : x ∈ p.support) : (toList p x).nthLe 0 (length_toList_pos_of_mem_support _ _ h) = x := by simp [toList] #align equiv.perm.to_list_nth_le_zero Equiv.Perm.toList_nthLe_zero variable {p} {x} theorem mem_toList_iff {y : α} : y ∈ toList p x ↔ SameCycle p x y ∧ x ∈ p.support := by simp only [toList, mem_range, mem_map] constructor · rintro ⟨n, hx, rfl⟩ refine ⟨⟨n, rfl⟩, ?_⟩ contrapose! hx rw [← support_cycleOf_eq_nil_iff] at hx simp [hx] · rintro ⟨h, hx⟩ simpa using h.exists_pow_eq_of_mem_support hx #align equiv.perm.mem_to_list_iff Equiv.Perm.mem_toList_iff set_option linter.deprecated false in theorem nodup_toList (p : Perm α) (x : α) : Nodup (toList p x) := by by_cases hx : p x = x · rw [← not_mem_support, ← toList_eq_nil_iff] at hx simp [hx] have hc : IsCycle (cycleOf p x) := isCycle_cycleOf p hx rw [nodup_iff_nthLe_inj] rintro n m hn hm rw [length_toList, ← hc.orderOf] at hm hn rw [← cycleOf_apply_self, ← Ne, ← mem_support] at hx rw [nthLe_toList, nthLe_toList, ← cycleOf_pow_apply_self p x n, ← cycleOf_pow_apply_self p x m] cases' n with n <;> cases' m with m · simp · rw [← hc.support_pow_of_pos_of_lt_orderOf m.zero_lt_succ hm, mem_support, cycleOf_pow_apply_self] at hx simp [hx.symm] · rw [← hc.support_pow_of_pos_of_lt_orderOf n.zero_lt_succ hn, mem_support, cycleOf_pow_apply_self] at hx simp [hx] intro h have hn' : ¬orderOf (p.cycleOf x) ∣ n.succ := Nat.not_dvd_of_pos_of_lt n.zero_lt_succ hn have hm' : ¬orderOf (p.cycleOf x) ∣ m.succ := Nat.not_dvd_of_pos_of_lt m.zero_lt_succ hm rw [← hc.support_pow_eq_iff] at hn' hm' rw [← Nat.mod_eq_of_lt hn, ← Nat.mod_eq_of_lt hm, ← pow_inj_mod] refine support_congr ?_ ?_ · rw [hm', hn'] · rw [hm'] intro y hy obtain ⟨k, rfl⟩ := hc.exists_pow_eq (mem_support.mp hx) (mem_support.mp hy) rw [← mul_apply, (Commute.pow_pow_self _ _ _).eq, mul_apply, h, ← mul_apply, ← mul_apply, (Commute.pow_pow_self _ _ _).eq] #align equiv.perm.nodup_to_list Equiv.Perm.nodup_toList set_option linter.deprecated false in
Mathlib/GroupTheory/Perm/Cycle/Concrete.lean
312
320
theorem next_toList_eq_apply (p : Perm α) (x y : α) (hy : y ∈ toList p x) : next (toList p x) y hy = p y := by
rw [mem_toList_iff] at hy obtain ⟨k, hk, hk'⟩ := hy.left.exists_pow_eq_of_mem_support hy.right rw [← nthLe_toList p x k (by simpa using hk)] at hk' simp_rw [← hk'] rw [next_nthLe _ (nodup_toList _ _), nthLe_toList, nthLe_toList, ← mul_apply, ← pow_succ', length_toList, ← pow_mod_orderOf_cycleOf_apply p (k + 1), IsCycle.orderOf] exact isCycle_cycleOf _ (mem_support.mp hy.right)
import Mathlib.Algebra.Order.Floor import Mathlib.Algebra.ContinuedFractions.Basic #align_import algebra.continued_fractions.computation.basic from "leanprover-community/mathlib"@"a7e36e48519ab281320c4d192da6a7b348ce40ad" namespace GeneralizedContinuedFraction -- Fix a carrier `K`. variable (K : Type*) structure IntFractPair where b : ℤ fr : K #align generalized_continued_fraction.int_fract_pair GeneralizedContinuedFraction.IntFractPair variable {K} namespace IntFractPair instance [Repr K] : Repr (IntFractPair K) := ⟨fun p _ => "(b : " ++ repr p.b ++ ", fract : " ++ repr p.fr ++ ")"⟩ instance inhabited [Inhabited K] : Inhabited (IntFractPair K) := ⟨⟨0, default⟩⟩ #align generalized_continued_fraction.int_fract_pair.inhabited GeneralizedContinuedFraction.IntFractPair.inhabited def mapFr {β : Type*} (f : K → β) (gp : IntFractPair K) : IntFractPair β := ⟨gp.b, f gp.fr⟩ set_option linter.uppercaseLean3 false in #align generalized_continued_fraction.int_fract_pair.mapFr GeneralizedContinuedFraction.IntFractPair.mapFr -- Note: this could be relaxed to something like `LinearOrderedDivisionRing` in the future. -- Fix a discrete linear ordered field with `floor` function. variable [LinearOrderedField K] [FloorRing K] protected def of (v : K) : IntFractPair K := ⟨⌊v⌋, Int.fract v⟩ #align generalized_continued_fraction.int_fract_pair.of GeneralizedContinuedFraction.IntFractPair.of protected def stream (v : K) : Stream' <| Option (IntFractPair K) | 0 => some (IntFractPair.of v) | n + 1 => (IntFractPair.stream v n).bind fun ap_n => if ap_n.fr = 0 then none else some (IntFractPair.of ap_n.fr⁻¹) #align generalized_continued_fraction.int_fract_pair.stream GeneralizedContinuedFraction.IntFractPair.stream
Mathlib/Algebra/ContinuedFractions/Computation/Basic.lean
159
161
theorem stream_isSeq (v : K) : (IntFractPair.stream v).IsSeq := by
intro _ hyp simp [IntFractPair.stream, hyp]
import Mathlib.Data.Finsupp.Multiset import Mathlib.Order.Bounded import Mathlib.SetTheory.Cardinal.PartENat import Mathlib.SetTheory.Ordinal.Principal import Mathlib.Tactic.Linarith #align_import set_theory.cardinal.ordinal from "leanprover-community/mathlib"@"7c2ce0c2da15516b4e65d0c9e254bb6dc93abd1f" noncomputable section open Function Set Cardinal Equiv Order Ordinal open scoped Classical universe u v w namespace Cardinal section UsingOrdinals theorem ord_isLimit {c} (co : ℵ₀ ≤ c) : (ord c).IsLimit := by refine ⟨fun h => aleph0_ne_zero ?_, fun a => lt_imp_lt_of_le_imp_le fun h => ?_⟩ · rw [← Ordinal.le_zero, ord_le] at h simpa only [card_zero, nonpos_iff_eq_zero] using co.trans h · rw [ord_le] at h ⊢ rwa [← @add_one_of_aleph0_le (card a), ← card_succ] rw [← ord_le, ← le_succ_of_isLimit, ord_le] · exact co.trans h · rw [ord_aleph0] exact omega_isLimit #align cardinal.ord_is_limit Cardinal.ord_isLimit theorem noMaxOrder {c} (h : ℵ₀ ≤ c) : NoMaxOrder c.ord.out.α := Ordinal.out_no_max_of_succ_lt (ord_isLimit h).2 section mulOrdinals
Mathlib/SetTheory/Cardinal/Ordinal.lean
500
543
theorem mul_eq_self {c : Cardinal} (h : ℵ₀ ≤ c) : c * c = c := by
refine le_antisymm ?_ (by simpa only [mul_one] using mul_le_mul_left' (one_le_aleph0.trans h) c) -- the only nontrivial part is `c * c ≤ c`. We prove it inductively. refine Acc.recOn (Cardinal.lt_wf.apply c) (fun c _ => Quotient.inductionOn c fun α IH ol => ?_) h -- consider the minimal well-order `r` on `α` (a type with cardinality `c`). rcases ord_eq α with ⟨r, wo, e⟩ letI := linearOrderOfSTO r haveI : IsWellOrder α (· < ·) := wo -- Define an order `s` on `α × α` by writing `(a, b) < (c, d)` if `max a b < max c d`, or -- the max are equal and `a < c`, or the max are equal and `a = c` and `b < d`. let g : α × α → α := fun p => max p.1 p.2 let f : α × α ↪ Ordinal × α × α := ⟨fun p : α × α => (typein (· < ·) (g p), p), fun p q => congr_arg Prod.snd⟩ let s := f ⁻¹'o Prod.Lex (· < ·) (Prod.Lex (· < ·) (· < ·)) -- this is a well order on `α × α`. haveI : IsWellOrder _ s := (RelEmbedding.preimage _ _).isWellOrder /- it suffices to show that this well order is smaller than `r` if it were larger, then `r` would be a strict prefix of `s`. It would be contained in `β × β` for some `β` of cardinality `< c`. By the inductive assumption, this set has the same cardinality as `β` (or it is finite if `β` is finite), so it is `< c`, which is a contradiction. -/ suffices type s ≤ type r by exact card_le_card this refine le_of_forall_lt fun o h => ?_ rcases typein_surj s h with ⟨p, rfl⟩ rw [← e, lt_ord] refine lt_of_le_of_lt (?_ : _ ≤ card (succ (typein (· < ·) (g p))) * card (succ (typein (· < ·) (g p)))) ?_ · have : { q | s q p } ⊆ insert (g p) { x | x < g p } ×ˢ insert (g p) { x | x < g p } := by intro q h simp only [s, f, Preimage, ge_iff_le, Embedding.coeFn_mk, Prod.lex_def, typein_lt_typein, typein_inj, mem_setOf_eq] at h exact max_le_iff.1 (le_iff_lt_or_eq.2 <| h.imp_right And.left) suffices H : (insert (g p) { x | r x (g p) } : Set α) ≃ Sum { x | r x (g p) } PUnit from ⟨(Set.embeddingOfSubset _ _ this).trans ((Equiv.Set.prod _ _).trans (H.prodCongr H)).toEmbedding⟩ refine (Equiv.Set.insert ?_).trans ((Equiv.refl _).sumCongr punitEquivPUnit) apply @irrefl _ r cases' lt_or_le (card (succ (typein (· < ·) (g p)))) ℵ₀ with qo qo · exact (mul_lt_aleph0 qo qo).trans_le ol · suffices (succ (typein LT.lt (g p))).card < ⟦α⟧ from (IH _ this qo).trans_lt this rw [← lt_ord] apply (ord_isLimit ol).2 rw [mk'_def, e] apply typein_lt_type
import Mathlib.Algebra.Group.Support import Mathlib.Algebra.Order.Monoid.WithTop import Mathlib.Data.Nat.Cast.Field #align_import algebra.char_zero.lemmas from "leanprover-community/mathlib"@"acee671f47b8e7972a1eb6f4eed74b4b3abce829" open Function Set section AddMonoidWithOne variable {α M : Type*} [AddMonoidWithOne M] [CharZero M] {n : ℕ} instance CharZero.NeZero.two : NeZero (2 : M) := ⟨by have : ((2 : ℕ) : M) ≠ 0 := Nat.cast_ne_zero.2 (by decide) rwa [Nat.cast_two] at this⟩ #align char_zero.ne_zero.two CharZero.NeZero.two section variable {R : Type*} [NonAssocSemiring R] [NoZeroDivisors R] [CharZero R] {a : R} @[simp] theorem add_self_eq_zero {a : R} : a + a = 0 ↔ a = 0 := by simp only [(two_mul a).symm, mul_eq_zero, two_ne_zero, false_or_iff] #align add_self_eq_zero add_self_eq_zero set_option linter.deprecated false @[simp] theorem bit0_eq_zero {a : R} : bit0 a = 0 ↔ a = 0 := add_self_eq_zero #align bit0_eq_zero bit0_eq_zero @[simp] theorem zero_eq_bit0 {a : R} : 0 = bit0 a ↔ a = 0 := by rw [eq_comm] exact bit0_eq_zero #align zero_eq_bit0 zero_eq_bit0 theorem bit0_ne_zero : bit0 a ≠ 0 ↔ a ≠ 0 := bit0_eq_zero.not #align bit0_ne_zero bit0_ne_zero theorem zero_ne_bit0 : 0 ≠ bit0 a ↔ a ≠ 0 := zero_eq_bit0.not #align zero_ne_bit0 zero_ne_bit0 end section variable {R : Type*} [NonAssocRing R] [NoZeroDivisors R] [CharZero R] @[simp] theorem neg_eq_self_iff {a : R} : -a = a ↔ a = 0 := neg_eq_iff_add_eq_zero.trans add_self_eq_zero #align neg_eq_self_iff neg_eq_self_iff @[simp] theorem eq_neg_self_iff {a : R} : a = -a ↔ a = 0 := eq_neg_iff_add_eq_zero.trans add_self_eq_zero #align eq_neg_self_iff eq_neg_self_iff theorem nat_mul_inj {n : ℕ} {a b : R} (h : (n : R) * a = (n : R) * b) : n = 0 ∨ a = b := by rw [← sub_eq_zero, ← mul_sub, mul_eq_zero, sub_eq_zero] at h exact mod_cast h #align nat_mul_inj nat_mul_inj theorem nat_mul_inj' {n : ℕ} {a b : R} (h : (n : R) * a = (n : R) * b) (w : n ≠ 0) : a = b := by simpa [w] using nat_mul_inj h #align nat_mul_inj' nat_mul_inj' set_option linter.deprecated false theorem bit0_injective : Function.Injective (bit0 : R → R) := fun a b h => by dsimp [bit0] at h simp only [(two_mul a).symm, (two_mul b).symm] at h refine nat_mul_inj' ?_ two_ne_zero exact mod_cast h #align bit0_injective bit0_injective theorem bit1_injective : Function.Injective (bit1 : R → R) := fun a b h => by simp only [bit1, add_left_inj] at h exact bit0_injective h #align bit1_injective bit1_injective @[simp] theorem bit0_eq_bit0 {a b : R} : bit0 a = bit0 b ↔ a = b := bit0_injective.eq_iff #align bit0_eq_bit0 bit0_eq_bit0 @[simp] theorem bit1_eq_bit1 {a b : R} : bit1 a = bit1 b ↔ a = b := bit1_injective.eq_iff #align bit1_eq_bit1 bit1_eq_bit1 @[simp] theorem bit1_eq_one {a : R} : bit1 a = 1 ↔ a = 0 := by rw [show (1 : R) = bit1 0 by simp, bit1_eq_bit1] #align bit1_eq_one bit1_eq_one @[simp] theorem one_eq_bit1 {a : R} : 1 = bit1 a ↔ a = 0 := by rw [eq_comm] exact bit1_eq_one #align one_eq_bit1 one_eq_bit1 end section variable {R : Type*} [DivisionRing R] [CharZero R] @[simp] lemma half_add_self (a : R) : (a + a) / 2 = a := by rw [← mul_two, mul_div_cancel_right₀ a two_ne_zero] #align half_add_self half_add_self @[simp] theorem add_halves' (a : R) : a / 2 + a / 2 = a := by rw [← add_div, half_add_self] #align add_halves' add_halves' theorem sub_half (a : R) : a - a / 2 = a / 2 := by rw [sub_eq_iff_eq_add, add_halves'] #align sub_half sub_half
Mathlib/Algebra/CharZero/Lemmas.lean
188
188
theorem half_sub (a : R) : a / 2 - a = -(a / 2) := by
rw [← neg_sub, sub_half]
import Mathlib.LinearAlgebra.Quotient #align_import linear_algebra.isomorphisms from "leanprover-community/mathlib"@"2738d2ca56cbc63be80c3bd48e9ed90ad94e947d" universe u v variable {R M M₂ M₃ : Type*} variable [Ring R] [AddCommGroup M] [AddCommGroup M₂] [AddCommGroup M₃] variable [Module R M] [Module R M₂] [Module R M₃] variable (f : M →ₗ[R] M₂) namespace LinearMap open Submodule section IsomorphismLaws noncomputable def quotKerEquivRange : (M ⧸ LinearMap.ker f) ≃ₗ[R] LinearMap.range f := (LinearEquiv.ofInjective (f.ker.liftQ f <| le_rfl) <| ker_eq_bot.mp <| Submodule.ker_liftQ_eq_bot _ _ _ (le_refl (LinearMap.ker f))).trans (LinearEquiv.ofEq _ _ <| Submodule.range_liftQ _ _ _) #align linear_map.quot_ker_equiv_range LinearMap.quotKerEquivRange noncomputable def quotKerEquivOfSurjective (f : M →ₗ[R] M₂) (hf : Function.Surjective f) : (M ⧸ LinearMap.ker f) ≃ₗ[R] M₂ := f.quotKerEquivRange.trans (LinearEquiv.ofTop (LinearMap.range f) (LinearMap.range_eq_top.2 hf)) #align linear_map.quot_ker_equiv_of_surjective LinearMap.quotKerEquivOfSurjective @[simp] theorem quotKerEquivRange_apply_mk (x : M) : (f.quotKerEquivRange (Submodule.Quotient.mk x) : M₂) = f x := rfl #align linear_map.quot_ker_equiv_range_apply_mk LinearMap.quotKerEquivRange_apply_mk @[simp] theorem quotKerEquivRange_symm_apply_image (x : M) (h : f x ∈ LinearMap.range f) : f.quotKerEquivRange.symm ⟨f x, h⟩ = f.ker.mkQ x := f.quotKerEquivRange.symm_apply_apply (f.ker.mkQ x) #align linear_map.quot_ker_equiv_range_symm_apply_image LinearMap.quotKerEquivRange_symm_apply_image -- Porting note: breaking up original definition of quotientInfToSupQuotient to avoid timing out abbrev subToSupQuotient (p p' : Submodule R M) : { x // x ∈ p } →ₗ[R] { x // x ∈ p ⊔ p' } ⧸ comap (Submodule.subtype (p ⊔ p')) p' := (comap (p ⊔ p').subtype p').mkQ.comp (Submodule.inclusion le_sup_left) -- Porting note: breaking up original definition of quotientInfToSupQuotient to avoid timing out theorem comap_leq_ker_subToSupQuotient (p p' : Submodule R M) : comap (Submodule.subtype p) (p ⊓ p') ≤ ker (subToSupQuotient p p') := by rw [LinearMap.ker_comp, Submodule.inclusion, comap_codRestrict, ker_mkQ, map_comap_subtype] exact comap_mono (inf_le_inf_right _ le_sup_left) def quotientInfToSupQuotient (p p' : Submodule R M) : (↥p) ⧸ (comap p.subtype (p ⊓ p')) →ₗ[R] (↥(p ⊔ p')) ⧸ (comap (p ⊔ p').subtype p') := (comap p.subtype (p ⊓ p')).liftQ (subToSupQuotient p p') (comap_leq_ker_subToSupQuotient p p') #align linear_map.quotient_inf_to_sup_quotient LinearMap.quotientInfToSupQuotient -- Porting note: breaking up original definition of quotientInfEquivSupQuotient to avoid timing out
Mathlib/LinearAlgebra/Isomorphisms.lean
81
85
theorem quotientInfEquivSupQuotient_injective (p p' : Submodule R M) : Function.Injective (quotientInfToSupQuotient p p') := by
rw [← ker_eq_bot, quotientInfToSupQuotient, ker_liftQ_eq_bot] rw [ker_comp, ker_mkQ] exact fun ⟨x, hx1⟩ hx2 => ⟨hx1, hx2⟩
import Mathlib.SetTheory.Cardinal.Basic import Mathlib.Topology.MetricSpace.Closeds import Mathlib.Topology.MetricSpace.Completion import Mathlib.Topology.MetricSpace.GromovHausdorffRealized import Mathlib.Topology.MetricSpace.Kuratowski #align_import topology.metric_space.gromov_hausdorff from "leanprover-community/mathlib"@"0c1f285a9f6e608ae2bdffa3f993eafb01eba829" noncomputable section open scoped Classical Topology ENNReal Cardinal set_option linter.uppercaseLean3 false local notation "ℓ_infty_ℝ" => lp (fun n : ℕ => ℝ) ∞ universe u v w open scoped Classical open Set Function TopologicalSpace Filter Metric Quotient Bornology open BoundedContinuousFunction Nat Int kuratowskiEmbedding open Sum (inl inr) attribute [local instance] metricSpaceSum namespace GromovHausdorff section GHSpace private def IsometryRel (x : NonemptyCompacts ℓ_infty_ℝ) (y : NonemptyCompacts ℓ_infty_ℝ) : Prop := Nonempty (x ≃ᵢ y) private theorem equivalence_isometryRel : Equivalence IsometryRel := ⟨fun _ => Nonempty.intro (IsometryEquiv.refl _), fun ⟨e⟩ => ⟨e.symm⟩, fun ⟨e⟩ ⟨f⟩ => ⟨e.trans f⟩⟩ instance IsometryRel.setoid : Setoid (NonemptyCompacts ℓ_infty_ℝ) := Setoid.mk IsometryRel equivalence_isometryRel #align Gromov_Hausdorff.isometry_rel.setoid GromovHausdorff.IsometryRel.setoid def GHSpace : Type := Quotient IsometryRel.setoid #align Gromov_Hausdorff.GH_space GromovHausdorff.GHSpace def toGHSpace (X : Type u) [MetricSpace X] [CompactSpace X] [Nonempty X] : GHSpace := ⟦NonemptyCompacts.kuratowskiEmbedding X⟧ #align Gromov_Hausdorff.to_GH_space GromovHausdorff.toGHSpace instance : Inhabited GHSpace := ⟨Quot.mk _ ⟨⟨{0}, isCompact_singleton⟩, singleton_nonempty _⟩⟩ -- Porting note(#5171): linter not yet ported; removed @[nolint has_nonempty_instance]; why? def GHSpace.Rep (p : GHSpace) : Type := (Quotient.out p : NonemptyCompacts ℓ_infty_ℝ) #align Gromov_Hausdorff.GH_space.rep GromovHausdorff.GHSpace.Rep
Mathlib/Topology/MetricSpace/GromovHausdorff.lean
103
119
theorem eq_toGHSpace_iff {X : Type u} [MetricSpace X] [CompactSpace X] [Nonempty X] {p : NonemptyCompacts ℓ_infty_ℝ} : ⟦p⟧ = toGHSpace X ↔ ∃ Ψ : X → ℓ_infty_ℝ, Isometry Ψ ∧ range Ψ = p := by
simp only [toGHSpace, Quotient.eq] refine ⟨fun h => ?_, ?_⟩ · rcases Setoid.symm h with ⟨e⟩ have f := (kuratowskiEmbedding.isometry X).isometryEquivOnRange.trans e use fun x => f x, isometry_subtype_coe.comp f.isometry erw [range_comp, f.range_eq_univ, Set.image_univ, Subtype.range_coe] · rintro ⟨Ψ, ⟨isomΨ, rangeΨ⟩⟩ have f := ((kuratowskiEmbedding.isometry X).isometryEquivOnRange.symm.trans isomΨ.isometryEquivOnRange).symm have E : (range Ψ ≃ᵢ NonemptyCompacts.kuratowskiEmbedding X) = (p ≃ᵢ range (kuratowskiEmbedding X)) := by dsimp only [NonemptyCompacts.kuratowskiEmbedding]; rw [rangeΨ]; rfl exact ⟨cast E f⟩
import Mathlib.Order.Antichain import Mathlib.Order.UpperLower.Basic import Mathlib.Order.Interval.Set.Basic import Mathlib.Order.RelIso.Set #align_import order.minimal from "leanprover-community/mathlib"@"59694bd07f0a39c5beccba34bd9f413a160782bf" open Function Set variable {α : Type*} (r r₁ r₂ : α → α → Prop) (s t : Set α) (a b : α) def maximals : Set α := { a ∈ s | ∀ ⦃b⦄, b ∈ s → r a b → r b a } #align maximals maximals def minimals : Set α := { a ∈ s | ∀ ⦃b⦄, b ∈ s → r b a → r a b } #align minimals minimals theorem maximals_subset : maximals r s ⊆ s := sep_subset _ _ #align maximals_subset maximals_subset theorem minimals_subset : minimals r s ⊆ s := sep_subset _ _ #align minimals_subset minimals_subset @[simp] theorem maximals_empty : maximals r ∅ = ∅ := sep_empty _ #align maximals_empty maximals_empty @[simp] theorem minimals_empty : minimals r ∅ = ∅ := sep_empty _ #align minimals_empty minimals_empty @[simp] theorem maximals_singleton : maximals r {a} = {a} := (maximals_subset _ _).antisymm <| singleton_subset_iff.2 <| ⟨rfl, by rintro b (rfl : b = a) exact id⟩ #align maximals_singleton maximals_singleton @[simp] theorem minimals_singleton : minimals r {a} = {a} := maximals_singleton _ _ #align minimals_singleton minimals_singleton theorem maximals_swap : maximals (swap r) s = minimals r s := rfl #align maximals_swap maximals_swap theorem minimals_swap : minimals (swap r) s = maximals r s := rfl #align minimals_swap minimals_swap section IsAntisymm variable {r s t a b} [IsAntisymm α r] theorem eq_of_mem_maximals (ha : a ∈ maximals r s) (hb : b ∈ s) (h : r a b) : a = b := antisymm h <| ha.2 hb h #align eq_of_mem_maximals eq_of_mem_maximals theorem eq_of_mem_minimals (ha : a ∈ minimals r s) (hb : b ∈ s) (h : r b a) : a = b := antisymm (ha.2 hb h) h #align eq_of_mem_minimals eq_of_mem_minimals set_option autoImplicit true theorem mem_maximals_iff : x ∈ maximals r s ↔ x ∈ s ∧ ∀ ⦃y⦄, y ∈ s → r x y → x = y := by simp only [maximals, Set.mem_sep_iff, and_congr_right_iff] refine fun _ ↦ ⟨fun h y hys hxy ↦ antisymm hxy (h hys hxy), fun h y hys hxy ↦ ?_⟩ convert hxy <;> rw [h hys hxy] theorem mem_maximals_setOf_iff : x ∈ maximals r (setOf P) ↔ P x ∧ ∀ ⦃y⦄, P y → r x y → x = y := mem_maximals_iff theorem mem_minimals_iff : x ∈ minimals r s ↔ x ∈ s ∧ ∀ ⦃y⦄, y ∈ s → r y x → x = y := @mem_maximals_iff _ _ _ (IsAntisymm.swap r) _ theorem mem_minimals_setOf_iff : x ∈ minimals r (setOf P) ↔ P x ∧ ∀ ⦃y⦄, P y → r y x → x = y := mem_minimals_iff theorem mem_minimals_iff_forall_lt_not_mem' (rlt : α → α → Prop) [IsNonstrictStrictOrder α r rlt] : x ∈ minimals r s ↔ x ∈ s ∧ ∀ ⦃y⦄, rlt y x → y ∉ s := by simp [minimals, right_iff_left_not_left_of r rlt, not_imp_not, imp.swap (a := _ ∈ _)] theorem mem_maximals_iff_forall_lt_not_mem' (rlt : α → α → Prop) [IsNonstrictStrictOrder α r rlt] : x ∈ maximals r s ↔ x ∈ s ∧ ∀ ⦃y⦄, rlt x y → y ∉ s := by simp [maximals, right_iff_left_not_left_of r rlt, not_imp_not, imp.swap (a := _ ∈ _)]
Mathlib/Order/Minimal.lean
121
128
theorem minimals_eq_minimals_of_subset_of_forall [IsTrans α r] (hts : t ⊆ s) (h : ∀ x ∈ s, ∃ y ∈ t, r y x) : minimals r s = minimals r t := by
refine Set.ext fun a ↦ ⟨fun ⟨has, hmin⟩ ↦ ⟨?_,fun b hbt ↦ hmin (hts hbt)⟩, fun ⟨hat, hmin⟩ ↦ ⟨hts hat, fun b hbs hba ↦ ?_⟩⟩ · obtain ⟨a', ha', haa'⟩ := h _ has rwa [antisymm (hmin (hts ha') haa') haa'] obtain ⟨b', hb't, hb'b⟩ := h b hbs rwa [antisymm (hmin hb't (Trans.trans hb'b hba)) (Trans.trans hb'b hba)]
import Mathlib.Topology.PartialHomeomorph import Mathlib.Analysis.Normed.Group.AddTorsor import Mathlib.Analysis.NormedSpace.Pointwise import Mathlib.Data.Real.Sqrt #align_import analysis.normed_space.basic from "leanprover-community/mathlib"@"bc91ed7093bf098d253401e69df601fc33dde156" open Set Metric Pointwise variable {E : Type*} [SeminormedAddCommGroup E] [NormedSpace ℝ E] noncomputable section @[simps (config := .lemmasOnly)] def PartialHomeomorph.univUnitBall : PartialHomeomorph E E where toFun x := (√(1 + ‖x‖ ^ 2))⁻¹ • x invFun y := (√(1 - ‖(y : E)‖ ^ 2))⁻¹ • (y : E) source := univ target := ball 0 1 map_source' x _ := by have : 0 < 1 + ‖x‖ ^ 2 := by positivity rw [mem_ball_zero_iff, norm_smul, Real.norm_eq_abs, abs_inv, ← _root_.div_eq_inv_mul, div_lt_one (abs_pos.mpr <| Real.sqrt_ne_zero'.mpr this), ← abs_norm x, ← sq_lt_sq, abs_norm, Real.sq_sqrt this.le] exact lt_one_add _ map_target' _ _ := trivial left_inv' x _ := by field_simp [norm_smul, smul_smul, (zero_lt_one_add_norm_sq x).ne', sq_abs, Real.sq_sqrt (zero_lt_one_add_norm_sq x).le, ← Real.sqrt_div (zero_lt_one_add_norm_sq x).le] right_inv' y hy := by have : 0 < 1 - ‖y‖ ^ 2 := by nlinarith [norm_nonneg y, mem_ball_zero_iff.1 hy] field_simp [norm_smul, smul_smul, this.ne', sq_abs, Real.sq_sqrt this.le, ← Real.sqrt_div this.le] open_source := isOpen_univ open_target := isOpen_ball continuousOn_toFun := by suffices Continuous fun (x:E) => (√(1 + ‖x‖ ^ 2))⁻¹ from (this.smul continuous_id).continuousOn refine Continuous.inv₀ ?_ fun x => Real.sqrt_ne_zero'.mpr (by positivity) continuity continuousOn_invFun := by have : ∀ y ∈ ball (0 : E) 1, √(1 - ‖(y : E)‖ ^ 2) ≠ 0 := fun y hy ↦ by rw [Real.sqrt_ne_zero'] nlinarith [norm_nonneg y, mem_ball_zero_iff.1 hy] exact ContinuousOn.smul (ContinuousOn.inv₀ (continuousOn_const.sub (continuous_norm.continuousOn.pow _)).sqrt this) continuousOn_id @[simp] theorem PartialHomeomorph.univUnitBall_apply_zero : univUnitBall (0 : E) = 0 := by simp [PartialHomeomorph.univUnitBall_apply] @[simp] theorem PartialHomeomorph.univUnitBall_symm_apply_zero : univUnitBall.symm (0 : E) = 0 := by simp [PartialHomeomorph.univUnitBall_symm_apply] @[simps! (config := .lemmasOnly)] def Homeomorph.unitBall : E ≃ₜ ball (0 : E) 1 := (Homeomorph.Set.univ _).symm.trans PartialHomeomorph.univUnitBall.toHomeomorphSourceTarget #align homeomorph_unit_ball Homeomorph.unitBall @[simp] theorem Homeomorph.coe_unitBall_apply_zero : (Homeomorph.unitBall (0 : E) : E) = 0 := PartialHomeomorph.univUnitBall_apply_zero #align coe_homeomorph_unit_ball_apply_zero Homeomorph.coe_unitBall_apply_zero variable {P : Type*} [PseudoMetricSpace P] [NormedAddTorsor E P] namespace PartialHomeomorph @[simps!] def unitBallBall (c : P) (r : ℝ) (hr : 0 < r) : PartialHomeomorph E P := ((Homeomorph.smulOfNeZero r hr.ne').trans (IsometryEquiv.vaddConst c).toHomeomorph).toPartialHomeomorphOfImageEq (ball 0 1) isOpen_ball (ball c r) <| by change (IsometryEquiv.vaddConst c) ∘ (r • ·) '' ball (0 : E) 1 = ball c r rw [image_comp, image_smul, smul_unitBall hr.ne', IsometryEquiv.image_ball] simp [abs_of_pos hr] def univBall (c : P) (r : ℝ) : PartialHomeomorph E P := if h : 0 < r then univUnitBall.trans' (unitBallBall c r h) rfl else (IsometryEquiv.vaddConst c).toHomeomorph.toPartialHomeomorph @[simp] theorem univBall_source (c : P) (r : ℝ) : (univBall c r).source = univ := by unfold univBall; split_ifs <;> rfl
Mathlib/Analysis/NormedSpace/HomeomorphBall.lean
130
131
theorem univBall_target (c : P) {r : ℝ} (hr : 0 < r) : (univBall c r).target = ball c r := by
rw [univBall, dif_pos hr]; rfl
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 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⟩ #align is_pi_system_Union_of_directed_le isPiSystem_iUnion_of_directed_le theorem isPiSystem_iUnion_of_monotone {α ι} [SemilatticeSup ι] (p : ι → Set (Set α)) (hp_pi : ∀ n, IsPiSystem (p n)) (hp_mono : Monotone p) : IsPiSystem (⋃ n, p n) := isPiSystem_iUnion_of_directed_le p hp_pi (Monotone.directed_le hp_mono) #align is_pi_system_Union_of_monotone isPiSystem_iUnion_of_monotone inductive generatePiSystem {α} (S : Set (Set α)) : Set (Set α) | base {s : Set α} (h_s : s ∈ S) : generatePiSystem S s | inter {s t : Set α} (h_s : generatePiSystem S s) (h_t : generatePiSystem S t) (h_nonempty : (s ∩ t).Nonempty) : generatePiSystem S (s ∩ t) #align generate_pi_system generatePiSystem theorem isPiSystem_generatePiSystem {α} (S : Set (Set α)) : IsPiSystem (generatePiSystem S) := fun _ h_s _ h_t h_nonempty => generatePiSystem.inter h_s h_t h_nonempty #align is_pi_system_generate_pi_system isPiSystem_generatePiSystem theorem subset_generatePiSystem_self {α} (S : Set (Set α)) : S ⊆ generatePiSystem S := fun _ => generatePiSystem.base #align subset_generate_pi_system_self subset_generatePiSystem_self theorem generatePiSystem_subset_self {α} {S : Set (Set α)} (h_S : IsPiSystem S) : generatePiSystem S ⊆ S := fun x h => by induction' h with _ h_s s u _ _ h_nonempty h_s h_u · exact h_s · exact h_S _ h_s _ h_u h_nonempty #align generate_pi_system_subset_self generatePiSystem_subset_self theorem generatePiSystem_eq {α} {S : Set (Set α)} (h_pi : IsPiSystem S) : generatePiSystem S = S := Set.Subset.antisymm (generatePiSystem_subset_self h_pi) (subset_generatePiSystem_self S) #align generate_pi_system_eq generatePiSystem_eq theorem generatePiSystem_mono {α} {S T : Set (Set α)} (hST : S ⊆ T) : generatePiSystem S ⊆ generatePiSystem T := fun t ht => by induction' ht with s h_s s u _ _ h_nonempty h_s h_u · exact generatePiSystem.base (Set.mem_of_subset_of_mem hST h_s) · exact isPiSystem_generatePiSystem T _ h_s _ h_u h_nonempty #align generate_pi_system_mono generatePiSystem_mono
Mathlib/MeasureTheory/PiSystem.lean
256
261
theorem generatePiSystem_measurableSet {α} [M : MeasurableSpace α] {S : Set (Set α)} (h_meas_S : ∀ s ∈ S, MeasurableSet s) (t : Set α) (h_in_pi : t ∈ generatePiSystem S) : MeasurableSet t := by
induction' h_in_pi with s h_s s u _ _ _ h_s h_u · apply h_meas_S _ h_s · apply MeasurableSet.inter h_s h_u
import Mathlib.Analysis.RCLike.Lemmas import Mathlib.MeasureTheory.Constructions.BorelSpace.Complex #align_import measure_theory.function.special_functions.is_R_or_C from "leanprover-community/mathlib"@"83a66c8775fa14ee5180c85cab98e970956401ad" noncomputable section open NNReal ENNReal namespace RCLike variable {𝕜 : Type*} [RCLike 𝕜] @[measurability] theorem measurable_re : Measurable (re : 𝕜 → ℝ) := continuous_re.measurable #align is_R_or_C.measurable_re RCLike.measurable_re @[measurability] theorem measurable_im : Measurable (im : 𝕜 → ℝ) := continuous_im.measurable #align is_R_or_C.measurable_im RCLike.measurable_im end RCLike section variable {α 𝕜 : Type*} [RCLike 𝕜] [MeasurableSpace α] {f : α → 𝕜} {μ : MeasureTheory.Measure α} @[measurability] theorem RCLike.measurable_ofReal : Measurable ((↑) : ℝ → 𝕜) := RCLike.continuous_ofReal.measurable #align is_R_or_C.measurable_of_real RCLike.measurable_ofReal theorem measurable_of_re_im (hre : Measurable fun x => RCLike.re (f x)) (him : Measurable fun x => RCLike.im (f x)) : Measurable f := by convert Measurable.add (M := 𝕜) (RCLike.measurable_ofReal.comp hre) ((RCLike.measurable_ofReal.comp him).mul_const RCLike.I) exact (RCLike.re_add_im _).symm #align measurable_of_re_im measurable_of_re_im
Mathlib/MeasureTheory/Function/SpecialFunctions/RCLike.lean
80
84
theorem aemeasurable_of_re_im (hre : AEMeasurable (fun x => RCLike.re (f x)) μ) (him : AEMeasurable (fun x => RCLike.im (f x)) μ) : AEMeasurable f μ := by
convert AEMeasurable.add (M := 𝕜) (RCLike.measurable_ofReal.comp_aemeasurable hre) ((RCLike.measurable_ofReal.comp_aemeasurable him).mul_const RCLike.I) exact (RCLike.re_add_im _).symm
import Mathlib.RingTheory.GradedAlgebra.Basic import Mathlib.Algebra.GradedMulAction import Mathlib.Algebra.DirectSum.Decomposition import Mathlib.Algebra.Module.BigOperators #align_import algebra.module.graded_module from "leanprover-community/mathlib"@"59cdeb0da2480abbc235b7e611ccd9a7e5603d7c" section open DirectSum variable {ιA ιB : Type*} (A : ιA → Type*) (M : ιB → Type*) namespace DirectSum open GradedMonoid class GdistribMulAction [AddMonoid ιA] [VAdd ιA ιB] [GMonoid A] [∀ i, AddMonoid (M i)] extends GMulAction A M where smul_add {i j} (a : A i) (b c : M j) : smul a (b + c) = smul a b + smul a c smul_zero {i j} (a : A i) : smul a (0 : M j) = 0 #align direct_sum.gdistrib_mul_action DirectSum.GdistribMulAction class Gmodule [AddMonoid ιA] [VAdd ιA ιB] [∀ i, AddMonoid (A i)] [∀ i, AddMonoid (M i)] [GMonoid A] extends GdistribMulAction A M where add_smul {i j} (a a' : A i) (b : M j) : smul (a + a') b = smul a b + smul a' b zero_smul {i j} (b : M j) : smul (0 : A i) b = 0 #align direct_sum.gmodule DirectSum.Gmodule instance GSemiring.toGmodule [AddMonoid ιA] [∀ i : ιA, AddCommMonoid (A i)] [h : GSemiring A] : Gmodule A A := { GMonoid.toGMulAction A with smul_add := fun _ _ _ => h.mul_add _ _ _ smul_zero := fun _ => h.mul_zero _ add_smul := fun _ _ => h.add_mul _ _ zero_smul := fun _ => h.zero_mul _ } #align direct_sum.gsemiring.to_gmodule DirectSum.GSemiring.toGmodule variable [AddMonoid ιA] [VAdd ιA ιB] [∀ i : ιA, AddCommMonoid (A i)] [∀ i, AddCommMonoid (M i)] @[simps] def gsmulHom [GMonoid A] [Gmodule A M] {i j} : A i →+ M j →+ M (i +ᵥ j) where toFun a := { toFun := fun b => GSMul.smul a b map_zero' := GdistribMulAction.smul_zero _ map_add' := GdistribMulAction.smul_add _ } map_zero' := AddMonoidHom.ext fun a => Gmodule.zero_smul a map_add' _a₁ _a₂ := AddMonoidHom.ext fun _b => Gmodule.add_smul _ _ _ #align direct_sum.gsmul_hom DirectSum.gsmulHom namespace Gmodule def smulAddMonoidHom [DecidableEq ιA] [DecidableEq ιB] [GMonoid A] [Gmodule A M] : (⨁ i, A i) →+ (⨁ i, M i) →+ ⨁ i, M i := toAddMonoid fun _i => AddMonoidHom.flip <| toAddMonoid fun _j => AddMonoidHom.flip <| (of M _).compHom.comp <| gsmulHom A M #align direct_sum.gmodule.smul_add_monoid_hom DirectSum.Gmodule.smulAddMonoidHom section open GradedMonoid DirectSum Gmodule instance [DecidableEq ιA] [DecidableEq ιB] [GMonoid A] [Gmodule A M] : SMul (⨁ i, A i) (⨁ i, M i) where smul x y := smulAddMonoidHom A M x y @[simp] theorem smul_def [DecidableEq ιA] [DecidableEq ιB] [GMonoid A] [Gmodule A M] (x : ⨁ i, A i) (y : ⨁ i, M i) : x • y = smulAddMonoidHom _ _ x y := rfl #align direct_sum.gmodule.smul_def DirectSum.Gmodule.smul_def @[simp]
Mathlib/Algebra/Module/GradedModule.lean
99
102
theorem smulAddMonoidHom_apply_of_of [DecidableEq ιA] [DecidableEq ιB] [GMonoid A] [Gmodule A M] {i j} (x : A i) (y : M j) : smulAddMonoidHom A M (DirectSum.of A i x) (of M j y) = of M (i +ᵥ j) (GSMul.smul x y) := by
simp [smulAddMonoidHom]
import Mathlib.Order.BooleanAlgebra import Mathlib.Logic.Equiv.Basic #align_import order.symm_diff from "leanprover-community/mathlib"@"6eb334bd8f3433d5b08ba156b8ec3e6af47e1904" open Function OrderDual variable {ι α β : Type*} {π : ι → Type*} def symmDiff [Sup α] [SDiff α] (a b : α) : α := a \ b ⊔ b \ a #align symm_diff symmDiff def bihimp [Inf α] [HImp α] (a b : α) : α := (b ⇨ a) ⊓ (a ⇨ b) #align bihimp bihimp scoped[symmDiff] infixl:100 " ∆ " => symmDiff scoped[symmDiff] infixl:100 " ⇔ " => bihimp open scoped symmDiff theorem symmDiff_def [Sup α] [SDiff α] (a b : α) : a ∆ b = a \ b ⊔ b \ a := rfl #align symm_diff_def symmDiff_def theorem bihimp_def [Inf α] [HImp α] (a b : α) : a ⇔ b = (b ⇨ a) ⊓ (a ⇨ b) := rfl #align bihimp_def bihimp_def theorem symmDiff_eq_Xor' (p q : Prop) : p ∆ q = Xor' p q := rfl #align symm_diff_eq_xor symmDiff_eq_Xor' @[simp] theorem bihimp_iff_iff {p q : Prop} : p ⇔ q ↔ (p ↔ q) := (iff_iff_implies_and_implies _ _).symm.trans Iff.comm #align bihimp_iff_iff bihimp_iff_iff @[simp] theorem Bool.symmDiff_eq_xor : ∀ p q : Bool, p ∆ q = xor p q := by decide #align bool.symm_diff_eq_bxor Bool.symmDiff_eq_xor section GeneralizedCoheytingAlgebra variable [GeneralizedCoheytingAlgebra α] (a b c d : α) @[simp] theorem toDual_symmDiff : toDual (a ∆ b) = toDual a ⇔ toDual b := rfl #align to_dual_symm_diff toDual_symmDiff @[simp] theorem ofDual_bihimp (a b : αᵒᵈ) : ofDual (a ⇔ b) = ofDual a ∆ ofDual b := rfl #align of_dual_bihimp ofDual_bihimp theorem symmDiff_comm : a ∆ b = b ∆ a := by simp only [symmDiff, sup_comm] #align symm_diff_comm symmDiff_comm instance symmDiff_isCommutative : Std.Commutative (α := α) (· ∆ ·) := ⟨symmDiff_comm⟩ #align symm_diff_is_comm symmDiff_isCommutative @[simp] theorem symmDiff_self : a ∆ a = ⊥ := by rw [symmDiff, sup_idem, sdiff_self] #align symm_diff_self symmDiff_self @[simp]
Mathlib/Order/SymmDiff.lean
125
125
theorem symmDiff_bot : a ∆ ⊥ = a := by
rw [symmDiff, sdiff_bot, bot_sdiff, sup_bot_eq]
import Mathlib.Order.BooleanAlgebra import Mathlib.Logic.Equiv.Basic #align_import order.symm_diff from "leanprover-community/mathlib"@"6eb334bd8f3433d5b08ba156b8ec3e6af47e1904" open Function OrderDual variable {ι α β : Type*} {π : ι → Type*} def symmDiff [Sup α] [SDiff α] (a b : α) : α := a \ b ⊔ b \ a #align symm_diff symmDiff def bihimp [Inf α] [HImp α] (a b : α) : α := (b ⇨ a) ⊓ (a ⇨ b) #align bihimp bihimp scoped[symmDiff] infixl:100 " ∆ " => symmDiff scoped[symmDiff] infixl:100 " ⇔ " => bihimp open scoped symmDiff theorem symmDiff_def [Sup α] [SDiff α] (a b : α) : a ∆ b = a \ b ⊔ b \ a := rfl #align symm_diff_def symmDiff_def theorem bihimp_def [Inf α] [HImp α] (a b : α) : a ⇔ b = (b ⇨ a) ⊓ (a ⇨ b) := rfl #align bihimp_def bihimp_def theorem symmDiff_eq_Xor' (p q : Prop) : p ∆ q = Xor' p q := rfl #align symm_diff_eq_xor symmDiff_eq_Xor' @[simp] theorem bihimp_iff_iff {p q : Prop} : p ⇔ q ↔ (p ↔ q) := (iff_iff_implies_and_implies _ _).symm.trans Iff.comm #align bihimp_iff_iff bihimp_iff_iff @[simp] theorem Bool.symmDiff_eq_xor : ∀ p q : Bool, p ∆ q = xor p q := by decide #align bool.symm_diff_eq_bxor Bool.symmDiff_eq_xor section GeneralizedCoheytingAlgebra variable [GeneralizedCoheytingAlgebra α] (a b c d : α) @[simp] theorem toDual_symmDiff : toDual (a ∆ b) = toDual a ⇔ toDual b := rfl #align to_dual_symm_diff toDual_symmDiff @[simp] theorem ofDual_bihimp (a b : αᵒᵈ) : ofDual (a ⇔ b) = ofDual a ∆ ofDual b := rfl #align of_dual_bihimp ofDual_bihimp
Mathlib/Order/SymmDiff.lean
113
113
theorem symmDiff_comm : a ∆ b = b ∆ a := by
simp only [symmDiff, sup_comm]
import Mathlib.Algebra.Order.BigOperators.Group.Finset import Mathlib.Data.Nat.Factors import Mathlib.Order.Interval.Finset.Nat #align_import number_theory.divisors from "leanprover-community/mathlib"@"e8638a0fcaf73e4500469f368ef9494e495099b3" open scoped Classical open Finset namespace Nat variable (n : ℕ) def divisors : Finset ℕ := Finset.filter (fun x : ℕ => x ∣ n) (Finset.Ico 1 (n + 1)) #align nat.divisors Nat.divisors def properDivisors : Finset ℕ := Finset.filter (fun x : ℕ => x ∣ n) (Finset.Ico 1 n) #align nat.proper_divisors Nat.properDivisors def divisorsAntidiagonal : Finset (ℕ × ℕ) := Finset.filter (fun x => x.fst * x.snd = n) (Ico 1 (n + 1) ×ˢ Ico 1 (n + 1)) #align nat.divisors_antidiagonal Nat.divisorsAntidiagonal variable {n} @[simp] theorem filter_dvd_eq_divisors (h : n ≠ 0) : (Finset.range n.succ).filter (· ∣ n) = n.divisors := by ext simp only [divisors, mem_filter, mem_range, mem_Ico, and_congr_left_iff, iff_and_self] exact fun ha _ => succ_le_iff.mpr (pos_of_dvd_of_pos ha h.bot_lt) #align nat.filter_dvd_eq_divisors Nat.filter_dvd_eq_divisors @[simp] theorem filter_dvd_eq_properDivisors (h : n ≠ 0) : (Finset.range n).filter (· ∣ n) = n.properDivisors := by ext simp only [properDivisors, mem_filter, mem_range, mem_Ico, and_congr_left_iff, iff_and_self] exact fun ha _ => succ_le_iff.mpr (pos_of_dvd_of_pos ha h.bot_lt) #align nat.filter_dvd_eq_proper_divisors Nat.filter_dvd_eq_properDivisors theorem properDivisors.not_self_mem : ¬n ∈ properDivisors n := by simp [properDivisors] #align nat.proper_divisors.not_self_mem Nat.properDivisors.not_self_mem @[simp] theorem mem_properDivisors {m : ℕ} : n ∈ properDivisors m ↔ n ∣ m ∧ n < m := by rcases eq_or_ne m 0 with (rfl | hm); · simp [properDivisors] simp only [and_comm, ← filter_dvd_eq_properDivisors hm, mem_filter, mem_range] #align nat.mem_proper_divisors Nat.mem_properDivisors theorem insert_self_properDivisors (h : n ≠ 0) : insert n (properDivisors n) = divisors n := by rw [divisors, properDivisors, Ico_succ_right_eq_insert_Ico (one_le_iff_ne_zero.2 h), Finset.filter_insert, if_pos (dvd_refl n)] #align nat.insert_self_proper_divisors Nat.insert_self_properDivisors theorem cons_self_properDivisors (h : n ≠ 0) : cons n (properDivisors n) properDivisors.not_self_mem = divisors n := by rw [cons_eq_insert, insert_self_properDivisors h] #align nat.cons_self_proper_divisors Nat.cons_self_properDivisors @[simp]
Mathlib/NumberTheory/Divisors.lean
95
99
theorem mem_divisors {m : ℕ} : n ∈ divisors m ↔ n ∣ m ∧ m ≠ 0 := by
rcases eq_or_ne m 0 with (rfl | hm); · simp [divisors] simp only [hm, Ne, not_false_iff, and_true_iff, ← filter_dvd_eq_divisors hm, mem_filter, mem_range, and_iff_right_iff_imp, Nat.lt_succ_iff] exact le_of_dvd hm.bot_lt
import Mathlib.CategoryTheory.Action import Mathlib.Combinatorics.Quiver.Arborescence import Mathlib.Combinatorics.Quiver.ConnectedComponent import Mathlib.GroupTheory.FreeGroup.IsFreeGroup #align_import group_theory.nielsen_schreier from "leanprover-community/mathlib"@"1bda4fc53de6ade5ab9da36f2192e24e2084a2ce" noncomputable section open scoped Classical universe v u open CategoryTheory CategoryTheory.ActionCategory CategoryTheory.SingleObj Quiver FreeGroup -- Porting note(#5171): @[nolint has_nonempty_instance] @[nolint unusedArguments] def IsFreeGroupoid.Generators (G) [Groupoid G] := G #align is_free_groupoid.generators IsFreeGroupoid.Generators class IsFreeGroupoid (G) [Groupoid.{v} G] where quiverGenerators : Quiver.{v + 1} (IsFreeGroupoid.Generators G) of : ∀ {a b : IsFreeGroupoid.Generators G}, (a ⟶ b) → ((show G from a) ⟶ b) unique_lift : ∀ {X : Type v} [Group X] (f : Labelling (IsFreeGroupoid.Generators G) X), ∃! F : G ⥤ CategoryTheory.SingleObj X, ∀ (a b) (g : a ⟶ b), F.map (of g) = f g #align is_free_groupoid IsFreeGroupoid attribute [nolint docBlame] IsFreeGroupoid.of IsFreeGroupoid.unique_lift namespace IsFreeGroupoid attribute [instance] quiverGenerators @[ext] theorem ext_functor {G} [Groupoid.{v} G] [IsFreeGroupoid G] {X : Type v} [Group X] (f g : G ⥤ CategoryTheory.SingleObj X) (h : ∀ (a b) (e : a ⟶ b), f.map (of e) = g.map (of e)) : f = g := let ⟨_, _, u⟩ := @unique_lift G _ _ X _ fun (a b : Generators G) (e : a ⟶ b) => g.map (of e) _root_.trans (u _ h) (u _ fun _ _ _ => rfl).symm #align is_free_groupoid.ext_functor IsFreeGroupoid.ext_functor instance actionGroupoidIsFree {G A : Type u} [Group G] [IsFreeGroup G] [MulAction G A] : IsFreeGroupoid (ActionCategory G A) where quiverGenerators := ⟨fun a b => { e : IsFreeGroup.Generators G // IsFreeGroup.of e • a.back = b.back }⟩ of := fun (e : { e // _}) => ⟨IsFreeGroup.of e, e.property⟩ unique_lift := by intro X _ f let f' : IsFreeGroup.Generators G → (A → X) ⋊[mulAutArrow] G := fun e => ⟨fun b => @f ⟨(), _⟩ ⟨(), b⟩ ⟨e, smul_inv_smul _ b⟩, IsFreeGroup.of e⟩ rcases IsFreeGroup.unique_lift f' with ⟨F', hF', uF'⟩ refine ⟨uncurry F' ?_, ?_, ?_⟩ · suffices SemidirectProduct.rightHom.comp F' = MonoidHom.id _ by -- Porting note: `MonoidHom.ext_iff` has been deprecated. exact DFunLike.ext_iff.mp this apply IsFreeGroup.ext_hom (fun x ↦ ?_) rw [MonoidHom.comp_apply, hF'] rfl · rintro ⟨⟨⟩, a : A⟩ ⟨⟨⟩, b⟩ ⟨e, h : IsFreeGroup.of e • a = b⟩ change (F' (IsFreeGroup.of _)).left _ = _ rw [hF'] cases inv_smul_eq_iff.mpr h.symm rfl · intro E hE have : curry E = F' := by apply uF' intro e ext · convert hE _ _ _ rfl · rfl apply Functor.hext · intro apply Unit.ext · refine ActionCategory.cases ?_ intros simp only [← this, uncurry_map, curry_apply_left, coe_back, homOfPair.val] rfl #align is_free_groupoid.action_groupoid_is_free IsFreeGroupoid.actionGroupoidIsFree private def symgen {G : Type u} [Groupoid.{v} G] [IsFreeGroupoid G] : G → Symmetrify (Generators G) := id -- #align is_free_groupoid.symgen IsFreeGroupoid.symgen
Mathlib/GroupTheory/FreeGroup/NielsenSchreier.lean
275
288
theorem path_nonempty_of_hom {G} [Groupoid.{u, u} G] [IsFreeGroupoid G] {a b : G} : Nonempty (a ⟶ b) → Nonempty (Path (symgen a) (symgen b)) := by
rintro ⟨p⟩ rw [← @WeaklyConnectedComponent.eq (Generators G), eq_comm, ← FreeGroup.of_injective.eq_iff, ← mul_inv_eq_one] let X := FreeGroup (WeaklyConnectedComponent <| Generators G) let f : G → X := fun g => FreeGroup.of (WeaklyConnectedComponent.mk g) let F : G ⥤ CategoryTheory.SingleObj.{u} (X : Type u) := SingleObj.differenceFunctor f change (F.map p) = ((@CategoryTheory.Functor.const G _ _ (SingleObj.category X)).obj ()).map p congr; ext rw [Functor.const_obj_map, id_as_one, differenceFunctor_map, @mul_inv_eq_one _ _ (f _)] apply congr_arg FreeGroup.of apply (WeaklyConnectedComponent.eq _ _).mpr exact ⟨Hom.toPath (Sum.inr (by assumption))⟩
import Mathlib.RingTheory.Polynomial.Cyclotomic.Roots import Mathlib.Tactic.ByContra import Mathlib.Topology.Algebra.Polynomial import Mathlib.NumberTheory.Padics.PadicVal import Mathlib.Analysis.Complex.Arg #align_import ring_theory.polynomial.cyclotomic.eval from "leanprover-community/mathlib"@"5bfbcca0a7ffdd21cf1682e59106d6c942434a32" namespace Polynomial open Finset Nat @[simp]
Mathlib/RingTheory/Polynomial/Cyclotomic/Eval.lean
29
32
theorem eval_one_cyclotomic_prime {R : Type*} [CommRing R] {p : ℕ} [hn : Fact p.Prime] : eval 1 (cyclotomic p R) = p := by
simp only [cyclotomic_prime, eval_X, one_pow, Finset.sum_const, eval_pow, eval_finset_sum, Finset.card_range, smul_one_eq_cast]
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
Mathlib/InformationTheory/Hamming.lean
78
81
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 _ _ _
import Mathlib.Analysis.SpecialFunctions.ImproperIntegrals import Mathlib.Analysis.Calculus.ParametricIntegral import Mathlib.MeasureTheory.Measure.Haar.NormedSpace #align_import analysis.mellin_transform from "leanprover-community/mathlib"@"917c3c072e487b3cccdbfeff17e75b40e45f66cb" open MeasureTheory Set Filter Asymptotics TopologicalSpace open Real open Complex hiding exp log abs_of_nonneg open scoped Topology noncomputable section section Defs variable {E : Type*} [NormedAddCommGroup E] [NormedSpace ℂ E] def MellinConvergent (f : ℝ → E) (s : ℂ) : Prop := IntegrableOn (fun t : ℝ => (t : ℂ) ^ (s - 1) • f t) (Ioi 0) #align mellin_convergent MellinConvergent
Mathlib/Analysis/MellinTransform.lean
47
50
theorem MellinConvergent.const_smul {f : ℝ → E} {s : ℂ} (hf : MellinConvergent f s) {𝕜 : Type*} [NontriviallyNormedField 𝕜] [NormedSpace 𝕜 E] [SMulCommClass ℂ 𝕜 E] (c : 𝕜) : MellinConvergent (fun t => c • f t) s := by
simpa only [MellinConvergent, smul_comm] using hf.smul c
import Mathlib.MeasureTheory.Function.ConditionalExpectation.Basic #align_import measure_theory.function.conditional_expectation.indicator from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982" noncomputable section open TopologicalSpace MeasureTheory.Lp Filter ContinuousLinearMap open scoped NNReal ENNReal Topology MeasureTheory namespace MeasureTheory variable {α 𝕜 E : Type*} {m m0 : MeasurableSpace α} [NormedAddCommGroup E] [NormedSpace ℝ E] [CompleteSpace E] {μ : Measure α} {f : α → E} {s : Set α} theorem condexp_ae_eq_restrict_zero (hs : MeasurableSet[m] s) (hf : f =ᵐ[μ.restrict s] 0) : μ[f|m] =ᵐ[μ.restrict s] 0 := by by_cases hm : m ≤ m0 swap; · simp_rw [condexp_of_not_le hm]; rfl by_cases hμm : SigmaFinite (μ.trim hm) swap; · simp_rw [condexp_of_not_sigmaFinite hm hμm]; rfl haveI : SigmaFinite (μ.trim hm) := hμm have : SigmaFinite ((μ.restrict s).trim hm) := by rw [← restrict_trim hm _ hs] exact Restrict.sigmaFinite _ s by_cases hf_int : Integrable f μ swap; · rw [condexp_undef hf_int] refine ae_eq_of_forall_setIntegral_eq_of_sigmaFinite' hm ?_ ?_ ?_ ?_ ?_ · exact fun t _ _ => integrable_condexp.integrableOn.integrableOn · exact fun t _ _ => (integrable_zero _ _ _).integrableOn · intro t ht _ rw [Measure.restrict_restrict (hm _ ht), setIntegral_condexp hm hf_int (ht.inter hs), ← Measure.restrict_restrict (hm _ ht)] refine setIntegral_congr_ae (hm _ ht) ?_ filter_upwards [hf] with x hx _ using hx · exact stronglyMeasurable_condexp.aeStronglyMeasurable' · exact stronglyMeasurable_zero.aeStronglyMeasurable' #align measure_theory.condexp_ae_eq_restrict_zero MeasureTheory.condexp_ae_eq_restrict_zero theorem condexp_indicator_aux (hs : MeasurableSet[m] s) (hf : f =ᵐ[μ.restrict sᶜ] 0) : μ[s.indicator f|m] =ᵐ[μ] s.indicator (μ[f|m]) := by by_cases hm : m ≤ m0 swap; · simp_rw [condexp_of_not_le hm, Set.indicator_zero']; rfl have hsf_zero : ∀ g : α → E, g =ᵐ[μ.restrict sᶜ] 0 → s.indicator g =ᵐ[μ] g := fun g => indicator_ae_eq_of_restrict_compl_ae_eq_zero (hm _ hs) refine ((hsf_zero (μ[f|m]) (condexp_ae_eq_restrict_zero hs.compl hf)).trans ?_).symm exact condexp_congr_ae (hsf_zero f hf).symm #align measure_theory.condexp_indicator_aux MeasureTheory.condexp_indicator_aux
Mathlib/MeasureTheory/Function/ConditionalExpectation/Indicator.lean
75
112
theorem condexp_indicator (hf_int : Integrable f μ) (hs : MeasurableSet[m] s) : μ[s.indicator f|m] =ᵐ[μ] s.indicator (μ[f|m]) := by
by_cases hm : m ≤ m0 swap; · simp_rw [condexp_of_not_le hm, Set.indicator_zero']; rfl by_cases hμm : SigmaFinite (μ.trim hm) swap; · simp_rw [condexp_of_not_sigmaFinite hm hμm, Set.indicator_zero']; rfl haveI : SigmaFinite (μ.trim hm) := hμm -- use `have` to perform what should be the first calc step because of an error I don't -- understand have : s.indicator (μ[f|m]) =ᵐ[μ] s.indicator (μ[s.indicator f + sᶜ.indicator f|m]) := by rw [Set.indicator_self_add_compl s f] refine (this.trans ?_).symm calc s.indicator (μ[s.indicator f + sᶜ.indicator f|m]) =ᵐ[μ] s.indicator (μ[s.indicator f|m] + μ[sᶜ.indicator f|m]) := by have : μ[s.indicator f + sᶜ.indicator f|m] =ᵐ[μ] μ[s.indicator f|m] + μ[sᶜ.indicator f|m] := condexp_add (hf_int.indicator (hm _ hs)) (hf_int.indicator (hm _ hs.compl)) filter_upwards [this] with x hx classical rw [Set.indicator_apply, Set.indicator_apply, hx] _ = s.indicator (μ[s.indicator f|m]) + s.indicator (μ[sᶜ.indicator f|m]) := (s.indicator_add' _ _) _ =ᵐ[μ] s.indicator (μ[s.indicator f|m]) + s.indicator (sᶜ.indicator (μ[sᶜ.indicator f|m])) := by refine Filter.EventuallyEq.rfl.add ?_ have : sᶜ.indicator (μ[sᶜ.indicator f|m]) =ᵐ[μ] μ[sᶜ.indicator f|m] := by refine (condexp_indicator_aux hs.compl ?_).symm.trans ?_ · exact indicator_ae_eq_restrict_compl (hm _ hs.compl) · rw [Set.indicator_indicator, Set.inter_self] filter_upwards [this] with x hx by_cases hxs : x ∈ s · simp only [hx, hxs, Set.indicator_of_mem] · simp only [hxs, Set.indicator_of_not_mem, not_false_iff] _ =ᵐ[μ] s.indicator (μ[s.indicator f|m]) := by rw [Set.indicator_indicator, Set.inter_compl_self, Set.indicator_empty', add_zero] _ =ᵐ[μ] μ[s.indicator f|m] := by refine (condexp_indicator_aux hs ?_).symm.trans ?_ · exact indicator_ae_eq_restrict_compl (hm _ hs) · rw [Set.indicator_indicator, Set.inter_self]
import Mathlib.Algebra.Module.Card import Mathlib.SetTheory.Cardinal.CountableCover import Mathlib.SetTheory.Cardinal.Continuum import Mathlib.Analysis.SpecificLimits.Normed import Mathlib.Topology.MetricSpace.Perfect universe u v open Filter Pointwise Set Function Cardinal open scoped Cardinal Topology theorem continuum_le_cardinal_of_nontriviallyNormedField (𝕜 : Type*) [NontriviallyNormedField 𝕜] [CompleteSpace 𝕜] : 𝔠 ≤ #𝕜 := by suffices ∃ f : (ℕ → Bool) → 𝕜, range f ⊆ univ ∧ Continuous f ∧ Injective f by rcases this with ⟨f, -, -, f_inj⟩ simpa using lift_mk_le_lift_mk_of_injective f_inj apply Perfect.exists_nat_bool_injection _ univ_nonempty refine ⟨isClosed_univ, preperfect_iff_nhds.2 (fun x _ U hU ↦ ?_)⟩ rcases NormedField.exists_norm_lt_one 𝕜 with ⟨c, c_pos, hc⟩ have A : Tendsto (fun n ↦ x + c^n) atTop (𝓝 (x + 0)) := tendsto_const_nhds.add (tendsto_pow_atTop_nhds_zero_of_norm_lt_one hc) rw [add_zero] at A have B : ∀ᶠ n in atTop, x + c^n ∈ U := tendsto_def.1 A U hU rcases B.exists with ⟨n, hn⟩ refine ⟨x + c^n, by simpa using hn, ?_⟩ simp only [ne_eq, add_right_eq_self] apply pow_ne_zero simpa using c_pos theorem continuum_le_cardinal_of_module (𝕜 : Type u) (E : Type v) [NontriviallyNormedField 𝕜] [CompleteSpace 𝕜] [AddCommGroup E] [Module 𝕜 E] [Nontrivial E] : 𝔠 ≤ #E := by have A : lift.{v} (𝔠 : Cardinal.{u}) ≤ lift.{v} (#𝕜) := by simpa using continuum_le_cardinal_of_nontriviallyNormedField 𝕜 simpa using A.trans (Cardinal.mk_le_of_module 𝕜 E) lemma cardinal_eq_of_mem_nhds_zero {E : Type*} (𝕜 : Type*) [NontriviallyNormedField 𝕜] [AddCommGroup E] [Module 𝕜 E] [TopologicalSpace E] [ContinuousSMul 𝕜 E] {s : Set E} (hs : s ∈ 𝓝 (0 : E)) : #s = #E := by obtain ⟨c, hc⟩ : ∃ x : 𝕜 , 1 < ‖x‖ := NormedField.exists_lt_norm 𝕜 1 have cn_ne : ∀ n, c^n ≠ 0 := by intro n apply pow_ne_zero rintro rfl simp only [norm_zero] at hc exact lt_irrefl _ (hc.trans zero_lt_one) have A : ∀ (x : E), ∀ᶠ n in (atTop : Filter ℕ), x ∈ c^n • s := by intro x have : Tendsto (fun n ↦ (c^n) ⁻¹ • x) atTop (𝓝 ((0 : 𝕜) • x)) := by have : Tendsto (fun n ↦ (c^n)⁻¹) atTop (𝓝 0) := by simp_rw [← inv_pow] apply tendsto_pow_atTop_nhds_zero_of_norm_lt_one rw [norm_inv] exact inv_lt_one hc exact Tendsto.smul_const this x rw [zero_smul] at this filter_upwards [this hs] with n (hn : (c ^ n)⁻¹ • x ∈ s) exact (mem_smul_set_iff_inv_smul_mem₀ (cn_ne n) _ _).2 hn have B : ∀ n, #(c^n • s :) = #s := by intro n have : (c^n • s :) ≃ s := { toFun := fun x ↦ ⟨(c^n)⁻¹ • x.1, (mem_smul_set_iff_inv_smul_mem₀ (cn_ne n) _ _).1 x.2⟩ invFun := fun x ↦ ⟨(c^n) • x.1, smul_mem_smul_set x.2⟩ left_inv := fun x ↦ by simp [smul_smul, mul_inv_cancel (cn_ne n)] right_inv := fun x ↦ by simp [smul_smul, inv_mul_cancel (cn_ne n)] } exact Cardinal.mk_congr this apply (Cardinal.mk_of_countable_eventually_mem A B).symm theorem cardinal_eq_of_mem_nhds {E : Type*} (𝕜 : Type*) [NontriviallyNormedField 𝕜] [AddCommGroup E] [Module 𝕜 E] [TopologicalSpace E] [ContinuousAdd E] [ContinuousSMul 𝕜 E] {s : Set E} {x : E} (hs : s ∈ 𝓝 x) : #s = #E := by let g := Homeomorph.addLeft x let t := g ⁻¹' s have : t ∈ 𝓝 0 := g.continuous.continuousAt.preimage_mem_nhds (by simpa [g] using hs) have A : #t = #E := cardinal_eq_of_mem_nhds_zero 𝕜 this have B : #t = #s := Cardinal.mk_subtype_of_equiv s g.toEquiv rwa [B] at A
Mathlib/Topology/Algebra/Module/Cardinality.lean
110
115
theorem cardinal_eq_of_isOpen {E : Type*} (𝕜 : Type*) [NontriviallyNormedField 𝕜] [AddCommGroup E] [Module 𝕜 E] [TopologicalSpace E] [ContinuousAdd E] [ContinuousSMul 𝕜 E] {s : Set E} (hs : IsOpen s) (h's : s.Nonempty) : #s = #E := by
rcases h's with ⟨x, hx⟩ exact cardinal_eq_of_mem_nhds 𝕜 (hs.mem_nhds hx)
import Mathlib.Data.Set.Pointwise.SMul #align_import algebra.add_torsor from "leanprover-community/mathlib"@"9003f28797c0664a49e4179487267c494477d853" class AddTorsor (G : outParam Type*) (P : Type*) [AddGroup G] extends AddAction G P, VSub G P where [nonempty : Nonempty P] vsub_vadd' : ∀ p₁ p₂ : P, (p₁ -ᵥ p₂ : G) +ᵥ p₂ = p₁ vadd_vsub' : ∀ (g : G) (p : P), g +ᵥ p -ᵥ p = g #align add_torsor AddTorsor -- Porting note(#12096): removed `nolint instance_priority`; lint not ported yet attribute [instance 100] AddTorsor.nonempty -- Porting note(#12094): removed nolint; dangerous_instance linter not ported yet --attribute [nolint dangerous_instance] AddTorsor.toVSub -- Porting note(#12096): linter not ported yet --@[nolint instance_priority] instance addGroupIsAddTorsor (G : Type*) [AddGroup G] : AddTorsor G G where vsub := Sub.sub vsub_vadd' := sub_add_cancel vadd_vsub' := add_sub_cancel_right #align add_group_is_add_torsor addGroupIsAddTorsor @[simp] theorem vsub_eq_sub {G : Type*} [AddGroup G] (g₁ g₂ : G) : g₁ -ᵥ g₂ = g₁ - g₂ := rfl #align vsub_eq_sub vsub_eq_sub section General variable {G : Type*} {P : Type*} [AddGroup G] [T : AddTorsor G P] @[simp] theorem vsub_vadd (p₁ p₂ : P) : p₁ -ᵥ p₂ +ᵥ p₂ = p₁ := AddTorsor.vsub_vadd' p₁ p₂ #align vsub_vadd vsub_vadd @[simp] theorem vadd_vsub (g : G) (p : P) : g +ᵥ p -ᵥ p = g := AddTorsor.vadd_vsub' g p #align vadd_vsub vadd_vsub theorem vadd_right_cancel {g₁ g₂ : G} (p : P) (h : g₁ +ᵥ p = g₂ +ᵥ p) : g₁ = g₂ := by -- Porting note: vadd_vsub g₁ → vadd_vsub g₁ p rw [← vadd_vsub g₁ p, h, vadd_vsub] #align vadd_right_cancel vadd_right_cancel @[simp] theorem vadd_right_cancel_iff {g₁ g₂ : G} (p : P) : g₁ +ᵥ p = g₂ +ᵥ p ↔ g₁ = g₂ := ⟨vadd_right_cancel p, fun h => h ▸ rfl⟩ #align vadd_right_cancel_iff vadd_right_cancel_iff theorem vadd_right_injective (p : P) : Function.Injective ((· +ᵥ p) : G → P) := fun _ _ => vadd_right_cancel p #align vadd_right_injective vadd_right_injective theorem vadd_vsub_assoc (g : G) (p₁ p₂ : P) : g +ᵥ p₁ -ᵥ p₂ = g + (p₁ -ᵥ p₂) := by apply vadd_right_cancel p₂ rw [vsub_vadd, add_vadd, vsub_vadd] #align vadd_vsub_assoc vadd_vsub_assoc @[simp] theorem vsub_self (p : P) : p -ᵥ p = (0 : G) := by rw [← zero_add (p -ᵥ p), ← vadd_vsub_assoc, vadd_vsub] #align vsub_self vsub_self theorem eq_of_vsub_eq_zero {p₁ p₂ : P} (h : p₁ -ᵥ p₂ = (0 : G)) : p₁ = p₂ := by rw [← vsub_vadd p₁ p₂, h, zero_vadd] #align eq_of_vsub_eq_zero eq_of_vsub_eq_zero @[simp] theorem vsub_eq_zero_iff_eq {p₁ p₂ : P} : p₁ -ᵥ p₂ = (0 : G) ↔ p₁ = p₂ := Iff.intro eq_of_vsub_eq_zero fun h => h ▸ vsub_self _ #align vsub_eq_zero_iff_eq vsub_eq_zero_iff_eq theorem vsub_ne_zero {p q : P} : p -ᵥ q ≠ (0 : G) ↔ p ≠ q := not_congr vsub_eq_zero_iff_eq #align vsub_ne_zero vsub_ne_zero @[simp] theorem vsub_add_vsub_cancel (p₁ p₂ p₃ : P) : p₁ -ᵥ p₂ + (p₂ -ᵥ p₃) = p₁ -ᵥ p₃ := by apply vadd_right_cancel p₃ rw [add_vadd, vsub_vadd, vsub_vadd, vsub_vadd] #align vsub_add_vsub_cancel vsub_add_vsub_cancel @[simp] theorem neg_vsub_eq_vsub_rev (p₁ p₂ : P) : -(p₁ -ᵥ p₂) = p₂ -ᵥ p₁ := by refine neg_eq_of_add_eq_zero_right (vadd_right_cancel p₁ ?_) rw [vsub_add_vsub_cancel, vsub_self] #align neg_vsub_eq_vsub_rev neg_vsub_eq_vsub_rev theorem vadd_vsub_eq_sub_vsub (g : G) (p q : P) : g +ᵥ p -ᵥ q = g - (q -ᵥ p) := by rw [vadd_vsub_assoc, sub_eq_add_neg, neg_vsub_eq_vsub_rev] #align vadd_vsub_eq_sub_vsub vadd_vsub_eq_sub_vsub
Mathlib/Algebra/AddTorsor.lean
165
167
theorem vsub_vadd_eq_vsub_sub (p₁ p₂ : P) (g : G) : p₁ -ᵥ (g +ᵥ p₂) = p₁ -ᵥ p₂ - g := by
rw [← add_right_inj (p₂ -ᵥ p₁ : G), vsub_add_vsub_cancel, ← neg_vsub_eq_vsub_rev, vadd_vsub, ← add_sub_assoc, ← neg_vsub_eq_vsub_rev, neg_add_self, zero_sub]
import Mathlib.Topology.Algebra.GroupWithZero import Mathlib.Topology.Order.OrderClosed #align_import topology.algebra.with_zero_topology from "leanprover-community/mathlib"@"3e0c4d76b6ebe9dfafb67d16f7286d2731ed6064" open Topology Filter TopologicalSpace Filter Set Function namespace WithZeroTopology variable {α Γ₀ : Type*} [LinearOrderedCommGroupWithZero Γ₀] {γ γ₁ γ₂ : Γ₀} {l : Filter α} {f : α → Γ₀} scoped instance (priority := 100) topologicalSpace : TopologicalSpace Γ₀ := nhdsAdjoint 0 <| ⨅ γ ≠ 0, 𝓟 (Iio γ) #align with_zero_topology.topological_space WithZeroTopology.topologicalSpace theorem nhds_eq_update : (𝓝 : Γ₀ → Filter Γ₀) = update pure 0 (⨅ γ ≠ 0, 𝓟 (Iio γ)) := by rw [nhds_nhdsAdjoint, sup_of_le_right] exact le_iInf₂ fun γ hγ ↦ le_principal_iff.2 <| zero_lt_iff.2 hγ #align with_zero_topology.nhds_eq_update WithZeroTopology.nhds_eq_update theorem nhds_zero : 𝓝 (0 : Γ₀) = ⨅ γ ≠ 0, 𝓟 (Iio γ) := by rw [nhds_eq_update, update_same] #align with_zero_topology.nhds_zero WithZeroTopology.nhds_zero theorem hasBasis_nhds_zero : (𝓝 (0 : Γ₀)).HasBasis (fun γ : Γ₀ => γ ≠ 0) Iio := by rw [nhds_zero] refine hasBasis_biInf_principal ?_ ⟨1, one_ne_zero⟩ exact directedOn_iff_directed.2 (Monotone.directed_ge fun a b hab => Iio_subset_Iio hab) #align with_zero_topology.has_basis_nhds_zero WithZeroTopology.hasBasis_nhds_zero theorem Iio_mem_nhds_zero (hγ : γ ≠ 0) : Iio γ ∈ 𝓝 (0 : Γ₀) := hasBasis_nhds_zero.mem_of_mem hγ #align with_zero_topology.Iio_mem_nhds_zero WithZeroTopology.Iio_mem_nhds_zero theorem nhds_zero_of_units (γ : Γ₀ˣ) : Iio ↑γ ∈ 𝓝 (0 : Γ₀) := Iio_mem_nhds_zero γ.ne_zero #align with_zero_topology.nhds_zero_of_units WithZeroTopology.nhds_zero_of_units theorem tendsto_zero : Tendsto f l (𝓝 (0 : Γ₀)) ↔ ∀ (γ₀) (_ : γ₀ ≠ 0), ∀ᶠ x in l, f x < γ₀ := by simp [nhds_zero] #align with_zero_topology.tendsto_zero WithZeroTopology.tendsto_zero @[simp] theorem nhds_of_ne_zero {γ : Γ₀} (h₀ : γ ≠ 0) : 𝓝 γ = pure γ := nhds_nhdsAdjoint_of_ne _ h₀ #align with_zero_topology.nhds_of_ne_zero WithZeroTopology.nhds_of_ne_zero theorem nhds_coe_units (γ : Γ₀ˣ) : 𝓝 (γ : Γ₀) = pure (γ : Γ₀) := nhds_of_ne_zero γ.ne_zero #align with_zero_topology.nhds_coe_units WithZeroTopology.nhds_coe_units
Mathlib/Topology/Algebra/WithZeroTopology.lean
101
101
theorem singleton_mem_nhds_of_units (γ : Γ₀ˣ) : ({↑γ} : Set Γ₀) ∈ 𝓝 (γ : Γ₀) := by
simp
import Mathlib.MeasureTheory.Group.Measure import Mathlib.MeasureTheory.Integral.IntegrableOn import Mathlib.MeasureTheory.Function.LocallyIntegrable open Asymptotics MeasureTheory Set Filter variable {α E F : Type*} [MeasurableSpace α] [NormedAddCommGroup E] [NormedAddCommGroup F] {f : α → E} {g : α → F} {a b : α} {μ : Measure α} {l : Filter α} theorem _root_.Asymptotics.IsBigO.integrableAtFilter [IsMeasurablyGenerated l] (hf : f =O[l] g) (hfm : StronglyMeasurableAtFilter f l μ) (hg : IntegrableAtFilter g l μ) : IntegrableAtFilter f l μ := by obtain ⟨C, hC⟩ := hf.bound obtain ⟨s, hsl, hsm, hfg, hf, hg⟩ := (hC.smallSets.and <| hfm.eventually.and hg.eventually).exists_measurable_mem_of_smallSets refine ⟨s, hsl, (hg.norm.const_mul C).mono hf ?_⟩ refine (ae_restrict_mem hsm).mono fun x hx ↦ ?_ exact (hfg x hx).trans (le_abs_self _) theorem _root_.Asymptotics.IsBigO.integrable (hfm : AEStronglyMeasurable f μ) (hf : f =O[⊤] g) (hg : Integrable g μ) : Integrable f μ := by rewrite [← integrableAtFilter_top] at * exact hf.integrableAtFilter ⟨univ, univ_mem, hfm.restrict⟩ hg variable [TopologicalSpace α] [SecondCountableTopology α] namespace MeasureTheory theorem LocallyIntegrable.integrable_of_isBigO_cocompact [IsMeasurablyGenerated (cocompact α)] (hf : LocallyIntegrable f μ) (ho : f =O[cocompact α] g) (hg : IntegrableAtFilter g (cocompact α) μ) : Integrable f μ := by refine integrable_iff_integrableAtFilter_cocompact.mpr ⟨ho.integrableAtFilter ?_ hg, hf⟩ exact hf.aestronglyMeasurable.stronglyMeasurableAtFilter section LinearOrder variable [LinearOrder α] [CompactIccSpace α] {g' : α → F} theorem LocallyIntegrable.integrable_of_isBigO_atBot_atTop [IsMeasurablyGenerated (atBot (α := α))] [IsMeasurablyGenerated (atTop (α := α))] (hf : LocallyIntegrable f μ) (ho : f =O[atBot] g) (hg : IntegrableAtFilter g atBot μ) (ho' : f =O[atTop] g') (hg' : IntegrableAtFilter g' atTop μ) : Integrable f μ := by refine integrable_iff_integrableAtFilter_atBot_atTop.mpr ⟨⟨ho.integrableAtFilter ?_ hg, ho'.integrableAtFilter ?_ hg'⟩, hf⟩ all_goals exact hf.aestronglyMeasurable.stronglyMeasurableAtFilter theorem LocallyIntegrableOn.integrableOn_of_isBigO_atBot [IsMeasurablyGenerated (atBot (α := α))] (hf : LocallyIntegrableOn f (Iic a) μ) (ho : f =O[atBot] g) (hg : IntegrableAtFilter g atBot μ) : IntegrableOn f (Iic a) μ := by refine integrableOn_Iic_iff_integrableAtFilter_atBot.mpr ⟨ho.integrableAtFilter ?_ hg, hf⟩ exact ⟨Iic a, Iic_mem_atBot a, hf.aestronglyMeasurable⟩ theorem LocallyIntegrableOn.integrableOn_of_isBigO_atTop [IsMeasurablyGenerated (atTop (α := α))] (hf : LocallyIntegrableOn f (Ici a) μ) (ho : f =O[atTop] g) (hg : IntegrableAtFilter g atTop μ) : IntegrableOn f (Ici a) μ := by refine integrableOn_Ici_iff_integrableAtFilter_atTop.mpr ⟨ho.integrableAtFilter ?_ hg, hf⟩ exact ⟨Ici a, Ici_mem_atTop a, hf.aestronglyMeasurable⟩
Mathlib/MeasureTheory/Integral/Asymptotics.lean
97
101
theorem LocallyIntegrable.integrable_of_isBigO_atBot [IsMeasurablyGenerated (atBot (α := α))] [OrderTop α] (hf : LocallyIntegrable f μ) (ho : f =O[atBot] g) (hg : IntegrableAtFilter g atBot μ) : Integrable f μ := by
refine integrable_iff_integrableAtFilter_atBot.mpr ⟨ho.integrableAtFilter ?_ hg, hf⟩ exact hf.aestronglyMeasurable.stronglyMeasurableAtFilter
import Mathlib.LinearAlgebra.CliffordAlgebra.Basic import Mathlib.Data.ZMod.Basic import Mathlib.RingTheory.GradedAlgebra.Basic #align_import linear_algebra.clifford_algebra.grading from "leanprover-community/mathlib"@"34020e531ebc4e8aac6d449d9eecbcd1508ea8d0" namespace CliffordAlgebra variable {R M : Type*} [CommRing R] [AddCommGroup M] [Module R M] variable {Q : QuadraticForm R M} open scoped DirectSum variable (Q) def evenOdd (i : ZMod 2) : Submodule R (CliffordAlgebra Q) := ⨆ j : { n : ℕ // ↑n = i }, LinearMap.range (ι Q) ^ (j : ℕ) #align clifford_algebra.even_odd CliffordAlgebra.evenOdd theorem one_le_evenOdd_zero : 1 ≤ evenOdd Q 0 := by refine le_trans ?_ (le_iSup _ ⟨0, Nat.cast_zero⟩) exact (pow_zero _).ge #align clifford_algebra.one_le_even_odd_zero CliffordAlgebra.one_le_evenOdd_zero theorem range_ι_le_evenOdd_one : LinearMap.range (ι Q) ≤ evenOdd Q 1 := by refine le_trans ?_ (le_iSup _ ⟨1, Nat.cast_one⟩) exact (pow_one _).ge #align clifford_algebra.range_ι_le_even_odd_one CliffordAlgebra.range_ι_le_evenOdd_one theorem ι_mem_evenOdd_one (m : M) : ι Q m ∈ evenOdd Q 1 := range_ι_le_evenOdd_one Q <| LinearMap.mem_range_self _ m #align clifford_algebra.ι_mem_even_odd_one CliffordAlgebra.ι_mem_evenOdd_one theorem ι_mul_ι_mem_evenOdd_zero (m₁ m₂ : M) : ι Q m₁ * ι Q m₂ ∈ evenOdd Q 0 := Submodule.mem_iSup_of_mem ⟨2, rfl⟩ (by rw [Subtype.coe_mk, pow_two] exact Submodule.mul_mem_mul (LinearMap.mem_range_self (ι Q) m₁) (LinearMap.mem_range_self (ι Q) m₂)) #align clifford_algebra.ι_mul_ι_mem_even_odd_zero CliffordAlgebra.ι_mul_ι_mem_evenOdd_zero
Mathlib/LinearAlgebra/CliffordAlgebra/Grading.lean
58
65
theorem evenOdd_mul_le (i j : ZMod 2) : evenOdd Q i * evenOdd Q j ≤ evenOdd Q (i + j) := by
simp_rw [evenOdd, Submodule.iSup_eq_span, Submodule.span_mul_span] apply Submodule.span_mono simp_rw [Set.iUnion_mul, Set.mul_iUnion, Set.iUnion_subset_iff, Set.mul_subset_iff] rintro ⟨xi, rfl⟩ ⟨yi, rfl⟩ x hx y hy refine Set.mem_iUnion.mpr ⟨⟨xi + yi, Nat.cast_add _ _⟩, ?_⟩ simp only [Subtype.coe_mk, Nat.cast_add, pow_add] exact Submodule.mul_mem_mul hx hy
import Mathlib.Analysis.NormedSpace.PiLp import Mathlib.Analysis.InnerProductSpace.PiL2 #align_import analysis.matrix from "leanprover-community/mathlib"@"46b633fd842bef9469441c0209906f6dddd2b4f5" noncomputable section open scoped NNReal Matrix namespace Matrix variable {R l m n α β : Type*} [Fintype l] [Fintype m] [Fintype n] section LinfLinf section SeminormedAddCommGroup variable [SeminormedAddCommGroup α] [SeminormedAddCommGroup β] protected def seminormedAddCommGroup : SeminormedAddCommGroup (Matrix m n α) := Pi.seminormedAddCommGroup #align matrix.seminormed_add_comm_group Matrix.seminormedAddCommGroup attribute [local instance] Matrix.seminormedAddCommGroup -- Porting note (#10756): new theorem (along with all the uses of this lemma below) theorem norm_def (A : Matrix m n α) : ‖A‖ = ‖fun i j => A i j‖ := rfl lemma norm_eq_sup_sup_nnnorm (A : Matrix m n α) : ‖A‖ = Finset.sup Finset.univ fun i ↦ Finset.sup Finset.univ fun j ↦ ‖A i j‖₊ := by simp_rw [Matrix.norm_def, Pi.norm_def, Pi.nnnorm_def] -- Porting note (#10756): new theorem (along with all the uses of this lemma below) theorem nnnorm_def (A : Matrix m n α) : ‖A‖₊ = ‖fun i j => A i j‖₊ := rfl theorem norm_le_iff {r : ℝ} (hr : 0 ≤ r) {A : Matrix m n α} : ‖A‖ ≤ r ↔ ∀ i j, ‖A i j‖ ≤ r := by simp_rw [norm_def, pi_norm_le_iff_of_nonneg hr] #align matrix.norm_le_iff Matrix.norm_le_iff theorem nnnorm_le_iff {r : ℝ≥0} {A : Matrix m n α} : ‖A‖₊ ≤ r ↔ ∀ i j, ‖A i j‖₊ ≤ r := by simp_rw [nnnorm_def, pi_nnnorm_le_iff] #align matrix.nnnorm_le_iff Matrix.nnnorm_le_iff theorem norm_lt_iff {r : ℝ} (hr : 0 < r) {A : Matrix m n α} : ‖A‖ < r ↔ ∀ i j, ‖A i j‖ < r := by simp_rw [norm_def, pi_norm_lt_iff hr] #align matrix.norm_lt_iff Matrix.norm_lt_iff theorem nnnorm_lt_iff {r : ℝ≥0} (hr : 0 < r) {A : Matrix m n α} : ‖A‖₊ < r ↔ ∀ i j, ‖A i j‖₊ < r := by simp_rw [nnnorm_def, pi_nnnorm_lt_iff hr] #align matrix.nnnorm_lt_iff Matrix.nnnorm_lt_iff theorem norm_entry_le_entrywise_sup_norm (A : Matrix m n α) {i : m} {j : n} : ‖A i j‖ ≤ ‖A‖ := (norm_le_pi_norm (A i) j).trans (norm_le_pi_norm A i) #align matrix.norm_entry_le_entrywise_sup_norm Matrix.norm_entry_le_entrywise_sup_norm theorem nnnorm_entry_le_entrywise_sup_nnnorm (A : Matrix m n α) {i : m} {j : n} : ‖A i j‖₊ ≤ ‖A‖₊ := (nnnorm_le_pi_nnnorm (A i) j).trans (nnnorm_le_pi_nnnorm A i) #align matrix.nnnorm_entry_le_entrywise_sup_nnnorm Matrix.nnnorm_entry_le_entrywise_sup_nnnorm @[simp]
Mathlib/Analysis/Matrix.lean
116
118
theorem nnnorm_map_eq (A : Matrix m n α) (f : α → β) (hf : ∀ a, ‖f a‖₊ = ‖a‖₊) : ‖A.map f‖₊ = ‖A‖₊ := by
simp only [nnnorm_def, Pi.nnnorm_def, Matrix.map_apply, hf]
import Mathlib.RingTheory.Derivation.ToSquareZero import Mathlib.RingTheory.Ideal.Cotangent import Mathlib.RingTheory.IsTensorProduct import Mathlib.Algebra.Exact import Mathlib.Algebra.MvPolynomial.PDeriv import Mathlib.Algebra.Polynomial.Derivation #align_import ring_theory.kaehler from "leanprover-community/mathlib"@"4b92a463033b5587bb011657e25e4710bfca7364" suppress_compilation section KaehlerDifferential open scoped TensorProduct open Algebra universe u v variable (R : Type u) (S : Type v) [CommRing R] [CommRing S] [Algebra R S] abbrev KaehlerDifferential.ideal : Ideal (S ⊗[R] S) := RingHom.ker (TensorProduct.lmul' R : S ⊗[R] S →ₐ[R] S) #align kaehler_differential.ideal KaehlerDifferential.ideal variable {S} theorem KaehlerDifferential.one_smul_sub_smul_one_mem_ideal (a : S) : (1 : S) ⊗ₜ[R] a - a ⊗ₜ[R] (1 : S) ∈ KaehlerDifferential.ideal R S := by simp [RingHom.mem_ker] #align kaehler_differential.one_smul_sub_smul_one_mem_ideal KaehlerDifferential.one_smul_sub_smul_one_mem_ideal variable {R} variable {M : Type*} [AddCommGroup M] [Module R M] [Module S M] [IsScalarTower R S M] def Derivation.tensorProductTo (D : Derivation R S M) : S ⊗[R] S →ₗ[S] M := TensorProduct.AlgebraTensorModule.lift ((LinearMap.lsmul S (S →ₗ[R] M)).flip D.toLinearMap) #align derivation.tensor_product_to Derivation.tensorProductTo theorem Derivation.tensorProductTo_tmul (D : Derivation R S M) (s t : S) : D.tensorProductTo (s ⊗ₜ t) = s • D t := rfl #align derivation.tensor_product_to_tmul Derivation.tensorProductTo_tmul
Mathlib/RingTheory/Kaehler.lean
78
99
theorem Derivation.tensorProductTo_mul (D : Derivation R S M) (x y : S ⊗[R] S) : D.tensorProductTo (x * y) = TensorProduct.lmul' (S := S) R x • D.tensorProductTo y + TensorProduct.lmul' (S := S) R y • D.tensorProductTo x := by
refine TensorProduct.induction_on x ?_ ?_ ?_ · rw [zero_mul, map_zero, map_zero, zero_smul, smul_zero, add_zero] swap · intro x₁ y₁ h₁ h₂ rw [add_mul, map_add, map_add, map_add, add_smul, smul_add, h₁, h₂, add_add_add_comm] intro x₁ x₂ refine TensorProduct.induction_on y ?_ ?_ ?_ · rw [mul_zero, map_zero, map_zero, zero_smul, smul_zero, add_zero] swap · intro x₁ y₁ h₁ h₂ rw [mul_add, map_add, map_add, map_add, add_smul, smul_add, h₁, h₂, add_add_add_comm] intro x y simp only [TensorProduct.tmul_mul_tmul, Derivation.tensorProductTo, TensorProduct.AlgebraTensorModule.lift_apply, TensorProduct.lift.tmul', TensorProduct.lmul'_apply_tmul] dsimp rw [D.leibniz] simp only [smul_smul, smul_add, mul_comm (x * y) x₁, mul_right_comm x₁ x₂, ← mul_assoc]
import Mathlib.Logic.Function.Basic import Mathlib.Logic.Relator import Mathlib.Init.Data.Quot import Mathlib.Tactic.Cases import Mathlib.Tactic.Use import Mathlib.Tactic.MkIffOfInductiveProp import Mathlib.Tactic.SimpRw #align_import logic.relation from "leanprover-community/mathlib"@"3365b20c2ffa7c35e47e5209b89ba9abdddf3ffe" open Function variable {α β γ δ ε ζ : Type*} namespace Relation variable {r : α → α → Prop} {a b c d : α} @[mk_iff ReflTransGen.cases_tail_iff] inductive ReflTransGen (r : α → α → Prop) (a : α) : α → Prop | refl : ReflTransGen r a a | tail {b c} : ReflTransGen r a b → r b c → ReflTransGen r a c #align relation.refl_trans_gen Relation.ReflTransGen #align relation.refl_trans_gen.cases_tail_iff Relation.ReflTransGen.cases_tail_iff attribute [refl] ReflTransGen.refl @[mk_iff] inductive ReflGen (r : α → α → Prop) (a : α) : α → Prop | refl : ReflGen r a a | single {b} : r a b → ReflGen r a b #align relation.refl_gen Relation.ReflGen #align relation.refl_gen_iff Relation.reflGen_iff @[mk_iff] inductive TransGen (r : α → α → Prop) (a : α) : α → Prop | single {b} : r a b → TransGen r a b | tail {b c} : TransGen r a b → r b c → TransGen r a c #align relation.trans_gen Relation.TransGen #align relation.trans_gen_iff Relation.transGen_iff attribute [refl] ReflGen.refl namespace ReflTransGen @[trans] theorem trans (hab : ReflTransGen r a b) (hbc : ReflTransGen r b c) : ReflTransGen r a c := by induction hbc with | refl => assumption | tail _ hcd hac => exact hac.tail hcd #align relation.refl_trans_gen.trans Relation.ReflTransGen.trans theorem single (hab : r a b) : ReflTransGen r a b := refl.tail hab #align relation.refl_trans_gen.single Relation.ReflTransGen.single theorem head (hab : r a b) (hbc : ReflTransGen r b c) : ReflTransGen r a c := by induction hbc with | refl => exact refl.tail hab | tail _ hcd hac => exact hac.tail hcd #align relation.refl_trans_gen.head Relation.ReflTransGen.head
Mathlib/Logic/Relation.lean
312
316
theorem symmetric (h : Symmetric r) : Symmetric (ReflTransGen r) := by
intro x y h induction' h with z w _ b c · rfl · apply Relation.ReflTransGen.head (h b) c
import Mathlib.LinearAlgebra.AffineSpace.AffineEquiv #align_import linear_algebra.affine_space.midpoint from "leanprover-community/mathlib"@"2196ab363eb097c008d4497125e0dde23fb36db2" open AffineMap AffineEquiv section variable (R : Type*) {V V' P P' : Type*} [Ring R] [Invertible (2 : R)] [AddCommGroup V] [Module R V] [AddTorsor V P] [AddCommGroup V'] [Module R V'] [AddTorsor V' P'] def midpoint (x y : P) : P := lineMap x y (⅟ 2 : R) #align midpoint midpoint variable {R} {x y z : P} @[simp] theorem AffineMap.map_midpoint (f : P →ᵃ[R] P') (a b : P) : f (midpoint R a b) = midpoint R (f a) (f b) := f.apply_lineMap a b _ #align affine_map.map_midpoint AffineMap.map_midpoint @[simp] theorem AffineEquiv.map_midpoint (f : P ≃ᵃ[R] P') (a b : P) : f (midpoint R a b) = midpoint R (f a) (f b) := f.apply_lineMap a b _ #align affine_equiv.map_midpoint AffineEquiv.map_midpoint theorem AffineEquiv.pointReflection_midpoint_left (x y : P) : pointReflection R (midpoint R x y) x = y := by rw [midpoint, pointReflection_apply, lineMap_apply, vadd_vsub, vadd_vadd, ← add_smul, ← two_mul, mul_invOf_self, one_smul, vsub_vadd] #align affine_equiv.point_reflection_midpoint_left AffineEquiv.pointReflection_midpoint_left @[simp] -- Porting note: added variant with `Equiv.pointReflection` for `simp` theorem Equiv.pointReflection_midpoint_left (x y : P) : (Equiv.pointReflection (midpoint R x y)) x = y := by rw [midpoint, pointReflection_apply, lineMap_apply, vadd_vsub, vadd_vadd, ← add_smul, ← two_mul, mul_invOf_self, one_smul, vsub_vadd] theorem midpoint_comm (x y : P) : midpoint R x y = midpoint R y x := by rw [midpoint, ← lineMap_apply_one_sub, one_sub_invOf_two, midpoint] #align midpoint_comm midpoint_comm theorem AffineEquiv.pointReflection_midpoint_right (x y : P) : pointReflection R (midpoint R x y) y = x := by rw [midpoint_comm, AffineEquiv.pointReflection_midpoint_left] #align affine_equiv.point_reflection_midpoint_right AffineEquiv.pointReflection_midpoint_right @[simp] -- Porting note: added variant with `Equiv.pointReflection` for `simp` theorem Equiv.pointReflection_midpoint_right (x y : P) : (Equiv.pointReflection (midpoint R x y)) y = x := by rw [midpoint_comm, Equiv.pointReflection_midpoint_left] theorem midpoint_vsub_midpoint (p₁ p₂ p₃ p₄ : P) : midpoint R p₁ p₂ -ᵥ midpoint R p₃ p₄ = midpoint R (p₁ -ᵥ p₃) (p₂ -ᵥ p₄) := lineMap_vsub_lineMap _ _ _ _ _ #align midpoint_vsub_midpoint midpoint_vsub_midpoint theorem midpoint_vadd_midpoint (v v' : V) (p p' : P) : midpoint R v v' +ᵥ midpoint R p p' = midpoint R (v +ᵥ p) (v' +ᵥ p') := lineMap_vadd_lineMap _ _ _ _ _ #align midpoint_vadd_midpoint midpoint_vadd_midpoint theorem midpoint_eq_iff {x y z : P} : midpoint R x y = z ↔ pointReflection R z x = y := eq_comm.trans ((injective_pointReflection_left_of_module R x).eq_iff' (AffineEquiv.pointReflection_midpoint_left x y)).symm #align midpoint_eq_iff midpoint_eq_iff @[simp] theorem midpoint_pointReflection_left (x y : P) : midpoint R (Equiv.pointReflection x y) y = x := midpoint_eq_iff.2 <| Equiv.pointReflection_involutive _ _ @[simp] theorem midpoint_pointReflection_right (x y : P) : midpoint R y (Equiv.pointReflection x y) = x := midpoint_eq_iff.2 rfl @[simp] theorem midpoint_vsub_left (p₁ p₂ : P) : midpoint R p₁ p₂ -ᵥ p₁ = (⅟ 2 : R) • (p₂ -ᵥ p₁) := lineMap_vsub_left _ _ _ #align midpoint_vsub_left midpoint_vsub_left @[simp] theorem midpoint_vsub_right (p₁ p₂ : P) : midpoint R p₁ p₂ -ᵥ p₂ = (⅟ 2 : R) • (p₁ -ᵥ p₂) := by rw [midpoint_comm, midpoint_vsub_left] #align midpoint_vsub_right midpoint_vsub_right @[simp] theorem left_vsub_midpoint (p₁ p₂ : P) : p₁ -ᵥ midpoint R p₁ p₂ = (⅟ 2 : R) • (p₁ -ᵥ p₂) := left_vsub_lineMap _ _ _ #align left_vsub_midpoint left_vsub_midpoint @[simp] theorem right_vsub_midpoint (p₁ p₂ : P) : p₂ -ᵥ midpoint R p₁ p₂ = (⅟ 2 : R) • (p₂ -ᵥ p₁) := by rw [midpoint_comm, left_vsub_midpoint] #align right_vsub_midpoint right_vsub_midpoint
Mathlib/LinearAlgebra/AffineSpace/Midpoint.lean
133
137
theorem midpoint_vsub (p₁ p₂ p : P) : midpoint R p₁ p₂ -ᵥ p = (⅟ 2 : R) • (p₁ -ᵥ p) + (⅟ 2 : R) • (p₂ -ᵥ p) := by
rw [← vsub_sub_vsub_cancel_right p₁ p p₂, smul_sub, sub_eq_add_neg, ← smul_neg, neg_vsub_eq_vsub_rev, add_assoc, invOf_two_smul_add_invOf_two_smul, ← vadd_vsub_assoc, midpoint_comm, midpoint, lineMap_apply]
import Mathlib.Algebra.BigOperators.Group.Multiset import Mathlib.Data.Multiset.Dedup #align_import data.multiset.bind from "leanprover-community/mathlib"@"f694c7dead66f5d4c80f446c796a5aad14707f0e" assert_not_exists MonoidWithZero assert_not_exists MulAction universe v variable {α : Type*} {β : Type v} {γ δ : Type*} namespace Multiset def join : Multiset (Multiset α) → Multiset α := sum #align multiset.join Multiset.join theorem coe_join : ∀ L : List (List α), join (L.map ((↑) : List α → Multiset α) : Multiset (Multiset α)) = L.join | [] => rfl | l :: L => by exact congr_arg (fun s : Multiset α => ↑l + s) (coe_join L) #align multiset.coe_join Multiset.coe_join @[simp] theorem join_zero : @join α 0 = 0 := rfl #align multiset.join_zero Multiset.join_zero @[simp] theorem join_cons (s S) : @join α (s ::ₘ S) = s + join S := sum_cons _ _ #align multiset.join_cons Multiset.join_cons @[simp] theorem join_add (S T) : @join α (S + T) = join S + join T := sum_add _ _ #align multiset.join_add Multiset.join_add @[simp] theorem singleton_join (a) : join ({a} : Multiset (Multiset α)) = a := sum_singleton _ #align multiset.singleton_join Multiset.singleton_join @[simp] theorem mem_join {a S} : a ∈ @join α S ↔ ∃ s ∈ S, a ∈ s := Multiset.induction_on S (by simp) <| by simp (config := { contextual := true }) [or_and_right, exists_or] #align multiset.mem_join Multiset.mem_join @[simp] theorem card_join (S) : card (@join α S) = sum (map card S) := Multiset.induction_on S (by simp) (by simp) #align multiset.card_join Multiset.card_join @[simp] theorem map_join (f : α → β) (S : Multiset (Multiset α)) : map f (join S) = join (map (map f) S) := by induction S using Multiset.induction with | empty => simp | cons _ _ ih => simp [ih] @[to_additive (attr := simp)] theorem prod_join [CommMonoid α] {S : Multiset (Multiset α)} : prod (join S) = prod (map prod S) := by induction S using Multiset.induction with | empty => simp | cons _ _ ih => simp [ih] theorem rel_join {r : α → β → Prop} {s t} (h : Rel (Rel r) s t) : Rel r s.join t.join := by induction h with | zero => simp | cons hab hst ih => simpa using hab.add ih #align multiset.rel_join Multiset.rel_join section Bind variable (a : α) (s t : Multiset α) (f g : α → Multiset β) def bind (s : Multiset α) (f : α → Multiset β) : Multiset β := (s.map f).join #align multiset.bind Multiset.bind @[simp]
Mathlib/Data/Multiset/Bind.lean
115
117
theorem coe_bind (l : List α) (f : α → List β) : (@bind α β l fun a => f a) = l.bind f := by
rw [List.bind, ← coe_join, List.map_map] rfl
import Mathlib.Topology.Connected.Basic open Set Topology universe u v variable {α : Type u} {β : Type v} {ι : Type*} {π : ι → Type*} [TopologicalSpace α] {s t u v : Set α} section LocallyConnectedSpace class LocallyConnectedSpace (α : Type*) [TopologicalSpace α] : Prop where open_connected_basis : ∀ x, (𝓝 x).HasBasis (fun s : Set α => IsOpen s ∧ x ∈ s ∧ IsConnected s) id #align locally_connected_space LocallyConnectedSpace theorem locallyConnectedSpace_iff_open_connected_basis : LocallyConnectedSpace α ↔ ∀ x, (𝓝 x).HasBasis (fun s : Set α => IsOpen s ∧ x ∈ s ∧ IsConnected s) id := ⟨@LocallyConnectedSpace.open_connected_basis _ _, LocallyConnectedSpace.mk⟩ #align locally_connected_space_iff_open_connected_basis locallyConnectedSpace_iff_open_connected_basis theorem locallyConnectedSpace_iff_open_connected_subsets : LocallyConnectedSpace α ↔ ∀ x, ∀ U ∈ 𝓝 x, ∃ V : Set α, V ⊆ U ∧ IsOpen V ∧ x ∈ V ∧ IsConnected V := by simp_rw [locallyConnectedSpace_iff_open_connected_basis] refine forall_congr' fun _ => ?_ constructor · intro h U hU rcases h.mem_iff.mp hU with ⟨V, hV, hVU⟩ exact ⟨V, hVU, hV⟩ · exact fun h => ⟨fun U => ⟨fun hU => let ⟨V, hVU, hV⟩ := h U hU ⟨V, hV, hVU⟩, fun ⟨V, ⟨hV, hxV, _⟩, hVU⟩ => mem_nhds_iff.mpr ⟨V, hVU, hV, hxV⟩⟩⟩ #align locally_connected_space_iff_open_connected_subsets locallyConnectedSpace_iff_open_connected_subsets instance (priority := 100) DiscreteTopology.toLocallyConnectedSpace (α) [TopologicalSpace α] [DiscreteTopology α] : LocallyConnectedSpace α := locallyConnectedSpace_iff_open_connected_subsets.2 fun x _U hU => ⟨{x}, singleton_subset_iff.2 <| mem_of_mem_nhds hU, isOpen_discrete _, rfl, isConnected_singleton⟩ #align discrete_topology.to_locally_connected_space DiscreteTopology.toLocallyConnectedSpace theorem connectedComponentIn_mem_nhds [LocallyConnectedSpace α] {F : Set α} {x : α} (h : F ∈ 𝓝 x) : connectedComponentIn F x ∈ 𝓝 x := by rw [(LocallyConnectedSpace.open_connected_basis x).mem_iff] at h rcases h with ⟨s, ⟨h1s, hxs, h2s⟩, hsF⟩ exact mem_nhds_iff.mpr ⟨s, h2s.isPreconnected.subset_connectedComponentIn hxs hsF, h1s, hxs⟩ #align connected_component_in_mem_nhds connectedComponentIn_mem_nhds protected theorem IsOpen.connectedComponentIn [LocallyConnectedSpace α] {F : Set α} {x : α} (hF : IsOpen F) : IsOpen (connectedComponentIn F x) := by rw [isOpen_iff_mem_nhds] intro y hy rw [connectedComponentIn_eq hy] exact connectedComponentIn_mem_nhds (hF.mem_nhds <| connectedComponentIn_subset F x hy) #align is_open.connected_component_in IsOpen.connectedComponentIn theorem isOpen_connectedComponent [LocallyConnectedSpace α] {x : α} : IsOpen (connectedComponent x) := by rw [← connectedComponentIn_univ] exact isOpen_univ.connectedComponentIn #align is_open_connected_component isOpen_connectedComponent theorem isClopen_connectedComponent [LocallyConnectedSpace α] {x : α} : IsClopen (connectedComponent x) := ⟨isClosed_connectedComponent, isOpen_connectedComponent⟩ #align is_clopen_connected_component isClopen_connectedComponent theorem locallyConnectedSpace_iff_connectedComponentIn_open : LocallyConnectedSpace α ↔ ∀ F : Set α, IsOpen F → ∀ x ∈ F, IsOpen (connectedComponentIn F x) := by constructor · intro h exact fun F hF x _ => hF.connectedComponentIn · intro h rw [locallyConnectedSpace_iff_open_connected_subsets] refine fun x U hU => ⟨connectedComponentIn (interior U) x, (connectedComponentIn_subset _ _).trans interior_subset, h _ isOpen_interior x ?_, mem_connectedComponentIn ?_, isConnected_connectedComponentIn_iff.mpr ?_⟩ <;> exact mem_interior_iff_mem_nhds.mpr hU #align locally_connected_space_iff_connected_component_in_open locallyConnectedSpace_iff_connectedComponentIn_open theorem locallyConnectedSpace_iff_connected_subsets : LocallyConnectedSpace α ↔ ∀ (x : α), ∀ U ∈ 𝓝 x, ∃ V ∈ 𝓝 x, IsPreconnected V ∧ V ⊆ U := by constructor · rw [locallyConnectedSpace_iff_open_connected_subsets] intro h x U hxU rcases h x U hxU with ⟨V, hVU, hV₁, hxV, hV₂⟩ exact ⟨V, hV₁.mem_nhds hxV, hV₂.isPreconnected, hVU⟩ · rw [locallyConnectedSpace_iff_connectedComponentIn_open] refine fun h U hU x _ => isOpen_iff_mem_nhds.mpr fun y hy => ?_ rw [connectedComponentIn_eq hy] rcases h y U (hU.mem_nhds <| (connectedComponentIn_subset _ _) hy) with ⟨V, hVy, hV, hVU⟩ exact Filter.mem_of_superset hVy (hV.subset_connectedComponentIn (mem_of_mem_nhds hVy) hVU) #align locally_connected_space_iff_connected_subsets locallyConnectedSpace_iff_connected_subsets theorem locallyConnectedSpace_iff_connected_basis : LocallyConnectedSpace α ↔ ∀ x, (𝓝 x).HasBasis (fun s : Set α => s ∈ 𝓝 x ∧ IsPreconnected s) id := by rw [locallyConnectedSpace_iff_connected_subsets] exact forall_congr' fun x => Filter.hasBasis_self.symm #align locally_connected_space_iff_connected_basis locallyConnectedSpace_iff_connected_basis
Mathlib/Topology/Connected/LocallyConnected.lean
125
132
theorem locallyConnectedSpace_of_connected_bases {ι : Type*} (b : α → ι → Set α) (p : α → ι → Prop) (hbasis : ∀ x, (𝓝 x).HasBasis (p x) (b x)) (hconnected : ∀ x i, p x i → IsPreconnected (b x i)) : LocallyConnectedSpace α := by
rw [locallyConnectedSpace_iff_connected_basis] exact fun x => (hbasis x).to_hasBasis (fun i hi => ⟨b x i, ⟨(hbasis x).mem_of_mem hi, hconnected x i hi⟩, subset_rfl⟩) fun s hs => ⟨(hbasis x).index s hs.1, ⟨(hbasis x).property_index hs.1, (hbasis x).set_index_subset hs.1⟩⟩
import Mathlib.Analysis.PSeries import Mathlib.Data.Real.Pi.Wallis import Mathlib.Tactic.AdaptationNote #align_import analysis.special_functions.stirling from "leanprover-community/mathlib"@"2c1d8ca2812b64f88992a5294ea3dba144755cd1" open scoped Topology Real Nat Asymptotics open Finset Filter Nat Real namespace Stirling noncomputable def stirlingSeq (n : ℕ) : ℝ := n ! / (√(2 * n : ℝ) * (n / exp 1) ^ n) #align stirling.stirling_seq Stirling.stirlingSeq @[simp] theorem stirlingSeq_zero : stirlingSeq 0 = 0 := by rw [stirlingSeq, cast_zero, mul_zero, Real.sqrt_zero, zero_mul, div_zero] #align stirling.stirling_seq_zero Stirling.stirlingSeq_zero @[simp] theorem stirlingSeq_one : stirlingSeq 1 = exp 1 / √2 := by rw [stirlingSeq, pow_one, factorial_one, cast_one, mul_one, mul_one_div, one_div_div] #align stirling.stirling_seq_one Stirling.stirlingSeq_one theorem log_stirlingSeq_formula (n : ℕ) : log (stirlingSeq n) = Real.log n ! - 1 / 2 * Real.log (2 * n) - n * log (n / exp 1) := by cases n · simp · rw [stirlingSeq, log_div, log_mul, sqrt_eq_rpow, log_rpow, Real.log_pow, tsub_tsub] <;> positivity -- Porting note: generalized from `n.succ` to `n` #align stirling.log_stirling_seq_formula Stirling.log_stirlingSeq_formulaₓ
Mathlib/Analysis/SpecialFunctions/Stirling.lean
77
93
theorem log_stirlingSeq_diff_hasSum (m : ℕ) : HasSum (fun k : ℕ => (1 : ℝ) / (2 * ↑(k + 1) + 1) * ((1 / (2 * ↑(m + 1) + 1)) ^ 2) ^ ↑(k + 1)) (log (stirlingSeq (m + 1)) - log (stirlingSeq (m + 2))) := by
let f (k : ℕ) := (1 : ℝ) / (2 * k + 1) * ((1 / (2 * ↑(m + 1) + 1)) ^ 2) ^ k change HasSum (fun k => f (k + 1)) _ rw [hasSum_nat_add_iff] convert (hasSum_log_one_add_inv m.cast_add_one_pos).mul_left ((↑(m + 1) : ℝ) + 1 / 2) using 1 · ext k dsimp only [f] rw [← pow_mul, pow_add] push_cast field_simp ring · have h : ∀ x ≠ (0 : ℝ), 1 + x⁻¹ = (x + 1) / x := fun x hx ↦ by field_simp [hx] simp (disch := positivity) only [log_stirlingSeq_formula, log_div, log_mul, log_exp, factorial_succ, cast_mul, cast_succ, cast_zero, range_one, sum_singleton, h] ring
import Mathlib.Data.Matrix.Basic import Mathlib.Data.PEquiv #align_import data.matrix.pequiv from "leanprover-community/mathlib"@"3e068ece210655b7b9a9477c3aff38a492400aa1" namespace PEquiv open Matrix universe u v variable {k l m n : Type*} variable {α : Type v} open Matrix def toMatrix [DecidableEq n] [Zero α] [One α] (f : m ≃. n) : Matrix m n α := of fun i j => if j ∈ f i then (1 : α) else 0 #align pequiv.to_matrix PEquiv.toMatrix -- TODO: set as an equation lemma for `toMatrix`, see mathlib4#3024 @[simp] theorem toMatrix_apply [DecidableEq n] [Zero α] [One α] (f : m ≃. n) (i j) : toMatrix f i j = if j ∈ f i then (1 : α) else 0 := rfl #align pequiv.to_matrix_apply PEquiv.toMatrix_apply theorem mul_matrix_apply [Fintype m] [DecidableEq m] [Semiring α] (f : l ≃. m) (M : Matrix m n α) (i j) : (f.toMatrix * M :) i j = Option.casesOn (f i) 0 fun fi => M fi j := by dsimp [toMatrix, Matrix.mul_apply] cases' h : f i with fi · simp [h] · rw [Finset.sum_eq_single fi] <;> simp (config := { contextual := true }) [h, eq_comm] #align pequiv.mul_matrix_apply PEquiv.mul_matrix_apply theorem toMatrix_symm [DecidableEq m] [DecidableEq n] [Zero α] [One α] (f : m ≃. n) : (f.symm.toMatrix : Matrix n m α) = f.toMatrixᵀ := by ext simp only [transpose, mem_iff_mem f, toMatrix_apply] congr #align pequiv.to_matrix_symm PEquiv.toMatrix_symm @[simp] theorem toMatrix_refl [DecidableEq n] [Zero α] [One α] : ((PEquiv.refl n).toMatrix : Matrix n n α) = 1 := by ext simp [toMatrix_apply, one_apply] #align pequiv.to_matrix_refl PEquiv.toMatrix_refl theorem matrix_mul_apply [Fintype m] [Semiring α] [DecidableEq n] (M : Matrix l m α) (f : m ≃. n) (i j) : (M * f.toMatrix :) i j = Option.casesOn (f.symm j) 0 fun fj => M i fj := by dsimp [toMatrix, Matrix.mul_apply] cases' h : f.symm j with fj · simp [h, ← f.eq_some_iff] · rw [Finset.sum_eq_single fj] · simp [h, ← f.eq_some_iff] · rintro b - n simp [h, ← f.eq_some_iff, n.symm] · simp #align pequiv.matrix_mul_apply PEquiv.matrix_mul_apply
Mathlib/Data/Matrix/PEquiv.lean
96
99
theorem toPEquiv_mul_matrix [Fintype m] [DecidableEq m] [Semiring α] (f : m ≃ m) (M : Matrix m n α) : f.toPEquiv.toMatrix * M = M.submatrix f id := by
ext i j rw [mul_matrix_apply, Equiv.toPEquiv_apply, submatrix_apply, id]
import Mathlib.Data.ZMod.Basic import Mathlib.GroupTheory.Coxeter.Basic namespace CoxeterSystem open List Matrix Function Classical variable {B : Type*} variable {W : Type*} [Group W] variable {M : CoxeterMatrix B} (cs : CoxeterSystem M W) local prefix:100 "s" => cs.simple local prefix:100 "π" => cs.wordProd private theorem exists_word_with_prod (w : W) : ∃ n ω, ω.length = n ∧ π ω = w := by rcases cs.wordProd_surjective w with ⟨ω, rfl⟩ use ω.length, ω noncomputable def length (w : W) : ℕ := Nat.find (cs.exists_word_with_prod w) local prefix:100 "ℓ" => cs.length theorem exists_reduced_word (w : W) : ∃ ω, ω.length = ℓ w ∧ w = π ω := by have := Nat.find_spec (cs.exists_word_with_prod w) tauto theorem length_wordProd_le (ω : List B) : ℓ (π ω) ≤ ω.length := Nat.find_min' (cs.exists_word_with_prod (π ω)) ⟨ω, by tauto⟩ @[simp] theorem length_one : ℓ (1 : W) = 0 := Nat.eq_zero_of_le_zero (cs.length_wordProd_le []) @[simp] theorem length_eq_zero_iff {w : W} : ℓ w = 0 ↔ w = 1 := by constructor · intro h rcases cs.exists_reduced_word w with ⟨ω, hω, rfl⟩ have : ω = [] := eq_nil_of_length_eq_zero (hω.trans h) rw [this, wordProd_nil] · rintro rfl exact cs.length_one @[simp]
Mathlib/GroupTheory/Coxeter/Length.lean
91
98
theorem length_inv (w : W) : ℓ (w⁻¹) = ℓ w := by
apply Nat.le_antisymm · rcases cs.exists_reduced_word w with ⟨ω, hω, rfl⟩ have := cs.length_wordProd_le (List.reverse ω) rwa [wordProd_reverse, length_reverse, hω] at this · rcases cs.exists_reduced_word w⁻¹ with ⟨ω, hω, h'ω⟩ have := cs.length_wordProd_le (List.reverse ω) rwa [wordProd_reverse, length_reverse, ← h'ω, hω, inv_inv] at this
import Mathlib.Analysis.Convex.Between import Mathlib.Analysis.Convex.Normed import Mathlib.Analysis.Normed.Group.AddTorsor #align_import analysis.convex.side from "leanprover-community/mathlib"@"a63928c34ec358b5edcda2bf7513c50052a5230f" variable {R V V' P P' : Type*} open AffineEquiv AffineMap namespace AffineSubspace section StrictOrderedCommRing variable [StrictOrderedCommRing R] [AddCommGroup V] [Module R V] [AddTorsor V P] variable [AddCommGroup V'] [Module R V'] [AddTorsor V' P'] def WSameSide (s : AffineSubspace R P) (x y : P) : Prop := ∃ᵉ (p₁ ∈ s) (p₂ ∈ s), SameRay R (x -ᵥ p₁) (y -ᵥ p₂) #align affine_subspace.w_same_side AffineSubspace.WSameSide def SSameSide (s : AffineSubspace R P) (x y : P) : Prop := s.WSameSide x y ∧ x ∉ s ∧ y ∉ s #align affine_subspace.s_same_side AffineSubspace.SSameSide def WOppSide (s : AffineSubspace R P) (x y : P) : Prop := ∃ᵉ (p₁ ∈ s) (p₂ ∈ s), SameRay R (x -ᵥ p₁) (p₂ -ᵥ y) #align affine_subspace.w_opp_side AffineSubspace.WOppSide def SOppSide (s : AffineSubspace R P) (x y : P) : Prop := s.WOppSide x y ∧ x ∉ s ∧ y ∉ s #align affine_subspace.s_opp_side AffineSubspace.SOppSide theorem WSameSide.map {s : AffineSubspace R P} {x y : P} (h : s.WSameSide x y) (f : P →ᵃ[R] P') : (s.map f).WSameSide (f x) (f y) := by rcases h with ⟨p₁, hp₁, p₂, hp₂, h⟩ refine ⟨f p₁, mem_map_of_mem f hp₁, f p₂, mem_map_of_mem f hp₂, ?_⟩ simp_rw [← linearMap_vsub] exact h.map f.linear #align affine_subspace.w_same_side.map AffineSubspace.WSameSide.map theorem _root_.Function.Injective.wSameSide_map_iff {s : AffineSubspace R P} {x y : P} {f : P →ᵃ[R] P'} (hf : Function.Injective f) : (s.map f).WSameSide (f x) (f y) ↔ s.WSameSide x y := by refine ⟨fun h => ?_, fun h => h.map _⟩ rcases h with ⟨fp₁, hfp₁, fp₂, hfp₂, h⟩ rw [mem_map] at hfp₁ hfp₂ rcases hfp₁ with ⟨p₁, hp₁, rfl⟩ rcases hfp₂ with ⟨p₂, hp₂, rfl⟩ refine ⟨p₁, hp₁, p₂, hp₂, ?_⟩ simp_rw [← linearMap_vsub, (f.linear_injective_iff.2 hf).sameRay_map_iff] at h exact h #align function.injective.w_same_side_map_iff Function.Injective.wSameSide_map_iff theorem _root_.Function.Injective.sSameSide_map_iff {s : AffineSubspace R P} {x y : P} {f : P →ᵃ[R] P'} (hf : Function.Injective f) : (s.map f).SSameSide (f x) (f y) ↔ s.SSameSide x y := by simp_rw [SSameSide, hf.wSameSide_map_iff, mem_map_iff_mem_of_injective hf] #align function.injective.s_same_side_map_iff Function.Injective.sSameSide_map_iff @[simp] theorem _root_.AffineEquiv.wSameSide_map_iff {s : AffineSubspace R P} {x y : P} (f : P ≃ᵃ[R] P') : (s.map ↑f).WSameSide (f x) (f y) ↔ s.WSameSide x y := (show Function.Injective f.toAffineMap from f.injective).wSameSide_map_iff #align affine_equiv.w_same_side_map_iff AffineEquiv.wSameSide_map_iff @[simp] theorem _root_.AffineEquiv.sSameSide_map_iff {s : AffineSubspace R P} {x y : P} (f : P ≃ᵃ[R] P') : (s.map ↑f).SSameSide (f x) (f y) ↔ s.SSameSide x y := (show Function.Injective f.toAffineMap from f.injective).sSameSide_map_iff #align affine_equiv.s_same_side_map_iff AffineEquiv.sSameSide_map_iff theorem WOppSide.map {s : AffineSubspace R P} {x y : P} (h : s.WOppSide x y) (f : P →ᵃ[R] P') : (s.map f).WOppSide (f x) (f y) := by rcases h with ⟨p₁, hp₁, p₂, hp₂, h⟩ refine ⟨f p₁, mem_map_of_mem f hp₁, f p₂, mem_map_of_mem f hp₂, ?_⟩ simp_rw [← linearMap_vsub] exact h.map f.linear #align affine_subspace.w_opp_side.map AffineSubspace.WOppSide.map
Mathlib/Analysis/Convex/Side.lean
109
119
theorem _root_.Function.Injective.wOppSide_map_iff {s : AffineSubspace R P} {x y : P} {f : P →ᵃ[R] P'} (hf : Function.Injective f) : (s.map f).WOppSide (f x) (f y) ↔ s.WOppSide x y := by
refine ⟨fun h => ?_, fun h => h.map _⟩ rcases h with ⟨fp₁, hfp₁, fp₂, hfp₂, h⟩ rw [mem_map] at hfp₁ hfp₂ rcases hfp₁ with ⟨p₁, hp₁, rfl⟩ rcases hfp₂ with ⟨p₂, hp₂, rfl⟩ refine ⟨p₁, hp₁, p₂, hp₂, ?_⟩ simp_rw [← linearMap_vsub, (f.linear_injective_iff.2 hf).sameRay_map_iff] at h exact h
import Mathlib.Control.Functor import Mathlib.Tactic.Common #align_import control.bifunctor from "leanprover-community/mathlib"@"dc1525fb3ef6eb4348fb1749c302d8abc303d34a" universe u₀ u₁ u₂ v₀ v₁ v₂ open Function class Bifunctor (F : Type u₀ → Type u₁ → Type u₂) where bimap : ∀ {α α' β β'}, (α → α') → (β → β') → F α β → F α' β' #align bifunctor Bifunctor export Bifunctor (bimap) class LawfulBifunctor (F : Type u₀ → Type u₁ → Type u₂) [Bifunctor F] : Prop where id_bimap : ∀ {α β} (x : F α β), bimap id id x = x bimap_bimap : ∀ {α₀ α₁ α₂ β₀ β₁ β₂} (f : α₀ → α₁) (f' : α₁ → α₂) (g : β₀ → β₁) (g' : β₁ → β₂) (x : F α₀ β₀), bimap f' g' (bimap f g x) = bimap (f' ∘ f) (g' ∘ g) x #align is_lawful_bifunctor LawfulBifunctor export LawfulBifunctor (id_bimap bimap_bimap) attribute [higher_order bimap_id_id] id_bimap #align is_lawful_bifunctor.bimap_id_id LawfulBifunctor.bimap_id_id attribute [higher_order bimap_comp_bimap] bimap_bimap #align is_lawful_bifunctor.bimap_comp_bimap LawfulBifunctor.bimap_comp_bimap export LawfulBifunctor (bimap_id_id bimap_comp_bimap) variable {F : Type u₀ → Type u₁ → Type u₂} [Bifunctor F] namespace Bifunctor abbrev fst {α α' β} (f : α → α') : F α β → F α' β := bimap f id #align bifunctor.fst Bifunctor.fst abbrev snd {α β β'} (f : β → β') : F α β → F α β' := bimap id f #align bifunctor.snd Bifunctor.snd variable [LawfulBifunctor F] @[higher_order fst_id] theorem id_fst : ∀ {α β} (x : F α β), fst id x = x := @id_bimap _ _ _ #align bifunctor.id_fst Bifunctor.id_fst #align bifunctor.fst_id Bifunctor.fst_id @[higher_order snd_id] theorem id_snd : ∀ {α β} (x : F α β), snd id x = x := @id_bimap _ _ _ #align bifunctor.id_snd Bifunctor.id_snd #align bifunctor.snd_id Bifunctor.snd_id @[higher_order fst_comp_fst]
Mathlib/Control/Bifunctor.lean
86
87
theorem comp_fst {α₀ α₁ α₂ β} (f : α₀ → α₁) (f' : α₁ → α₂) (x : F α₀ β) : fst f' (fst f x) = fst (f' ∘ f) x := by
simp [fst, bimap_bimap]
import Mathlib.Algebra.MvPolynomial.Rename #align_import data.mv_polynomial.comap from "leanprover-community/mathlib"@"aba31c938d3243cc671be7091b28a1e0814647ee" namespace MvPolynomial variable {σ : Type*} {τ : Type*} {υ : Type*} {R : Type*} [CommSemiring R] noncomputable def comap (f : MvPolynomial σ R →ₐ[R] MvPolynomial τ R) : (τ → R) → σ → R := fun x i => aeval x (f (X i)) #align mv_polynomial.comap MvPolynomial.comap @[simp] theorem comap_apply (f : MvPolynomial σ R →ₐ[R] MvPolynomial τ R) (x : τ → R) (i : σ) : comap f x i = aeval x (f (X i)) := rfl #align mv_polynomial.comap_apply MvPolynomial.comap_apply @[simp]
Mathlib/Algebra/MvPolynomial/Comap.lean
48
50
theorem comap_id_apply (x : σ → R) : comap (AlgHom.id R (MvPolynomial σ R)) x = x := by
funext i simp only [comap, AlgHom.id_apply, id, aeval_X]
import Mathlib.Analysis.SpecialFunctions.Trigonometric.Angle import Mathlib.Analysis.SpecialFunctions.Trigonometric.Inverse #align_import analysis.special_functions.complex.arg from "leanprover-community/mathlib"@"2c1d8ca2812b64f88992a5294ea3dba144755cd1" open Filter Metric Set open scoped ComplexConjugate Real Topology namespace Complex variable {a x z : ℂ} noncomputable def arg (x : ℂ) : ℝ := if 0 ≤ x.re then Real.arcsin (x.im / abs x) else if 0 ≤ x.im then Real.arcsin ((-x).im / abs x) + π else Real.arcsin ((-x).im / abs x) - π #align complex.arg Complex.arg theorem sin_arg (x : ℂ) : Real.sin (arg x) = x.im / abs x := by unfold arg; split_ifs <;> simp [sub_eq_add_neg, arg, Real.sin_arcsin (abs_le.1 (abs_im_div_abs_le_one x)).1 (abs_le.1 (abs_im_div_abs_le_one x)).2, Real.sin_add, neg_div, Real.arcsin_neg, Real.sin_neg] #align complex.sin_arg Complex.sin_arg theorem cos_arg {x : ℂ} (hx : x ≠ 0) : Real.cos (arg x) = x.re / abs x := by rw [arg] split_ifs with h₁ h₂ · rw [Real.cos_arcsin] field_simp [Real.sqrt_sq, (abs.pos hx).le, *] · rw [Real.cos_add_pi, Real.cos_arcsin] field_simp [Real.sqrt_div (sq_nonneg _), Real.sqrt_sq_eq_abs, _root_.abs_of_neg (not_le.1 h₁), *] · rw [Real.cos_sub_pi, Real.cos_arcsin] field_simp [Real.sqrt_div (sq_nonneg _), Real.sqrt_sq_eq_abs, _root_.abs_of_neg (not_le.1 h₁), *] #align complex.cos_arg Complex.cos_arg @[simp] theorem abs_mul_exp_arg_mul_I (x : ℂ) : ↑(abs x) * exp (arg x * I) = x := by rcases eq_or_ne x 0 with (rfl | hx) · simp · have : abs x ≠ 0 := abs.ne_zero hx apply Complex.ext <;> field_simp [sin_arg, cos_arg hx, this, mul_comm (abs x)] set_option linter.uppercaseLean3 false in #align complex.abs_mul_exp_arg_mul_I Complex.abs_mul_exp_arg_mul_I @[simp]
Mathlib/Analysis/SpecialFunctions/Complex/Arg.lean
63
64
theorem abs_mul_cos_add_sin_mul_I (x : ℂ) : (abs x * (cos (arg x) + sin (arg x) * I) : ℂ) = x := by
rw [← exp_mul_I, abs_mul_exp_arg_mul_I]
import Mathlib.AlgebraicTopology.DoldKan.FunctorGamma import Mathlib.AlgebraicTopology.DoldKan.SplitSimplicialObject import Mathlib.CategoryTheory.Idempotents.HomologicalComplex #align_import algebraic_topology.dold_kan.gamma_comp_n from "leanprover-community/mathlib"@"32a7e535287f9c73f2e4d2aef306a39190f0b504" noncomputable section open CategoryTheory CategoryTheory.Category CategoryTheory.Limits CategoryTheory.Idempotents Opposite SimplicialObject Simplicial namespace AlgebraicTopology namespace DoldKan variable {C : Type*} [Category C] [Preadditive C] [HasFiniteCoproducts C] @[simps!] def Γ₀NondegComplexIso (K : ChainComplex C ℕ) : (Γ₀.splitting K).nondegComplex ≅ K := HomologicalComplex.Hom.isoOfComponents (fun n => Iso.refl _) (by rintro _ n (rfl : n + 1 = _) dsimp simp only [id_comp, comp_id, AlternatingFaceMapComplex.obj_d_eq, Preadditive.sum_comp, Preadditive.comp_sum] rw [Fintype.sum_eq_single (0 : Fin (n + 2))] · simp only [Fin.val_zero, pow_zero, one_zsmul] erw [Γ₀.Obj.mapMono_on_summand_id_assoc, Γ₀.Obj.Termwise.mapMono_δ₀, Splitting.cofan_inj_πSummand_eq_id, comp_id] · intro i hi dsimp simp only [Preadditive.zsmul_comp, Preadditive.comp_zsmul, assoc] erw [Γ₀.Obj.mapMono_on_summand_id_assoc, Γ₀.Obj.Termwise.mapMono_eq_zero, zero_comp, zsmul_zero] · intro h replace h := congr_arg SimplexCategory.len h change n + 1 = n at h omega · simpa only [Isδ₀.iff] using hi) #align algebraic_topology.dold_kan.Γ₀_nondeg_complex_iso AlgebraicTopology.DoldKan.Γ₀NondegComplexIso def Γ₀'CompNondegComplexFunctor : Γ₀' ⋙ Split.nondegComplexFunctor ≅ 𝟭 (ChainComplex C ℕ) := NatIso.ofComponents Γ₀NondegComplexIso #align algebraic_topology.dold_kan.Γ₀'_comp_nondeg_complex_functor AlgebraicTopology.DoldKan.Γ₀'CompNondegComplexFunctor def N₁Γ₀ : Γ₀ ⋙ N₁ ≅ toKaroubi (ChainComplex C ℕ) := calc Γ₀ ⋙ N₁ ≅ Γ₀' ⋙ Split.forget C ⋙ N₁ := Functor.associator _ _ _ _ ≅ Γ₀' ⋙ Split.nondegComplexFunctor ⋙ toKaroubi _ := (isoWhiskerLeft Γ₀' Split.toKaroubiNondegComplexFunctorIsoN₁.symm) _ ≅ (Γ₀' ⋙ Split.nondegComplexFunctor) ⋙ toKaroubi _ := (Functor.associator _ _ _).symm _ ≅ 𝟭 _ ⋙ toKaroubi (ChainComplex C ℕ) := isoWhiskerRight Γ₀'CompNondegComplexFunctor _ _ ≅ toKaroubi (ChainComplex C ℕ) := Functor.leftUnitor _ set_option linter.uppercaseLean3 false in #align algebraic_topology.dold_kan.N₁Γ₀ AlgebraicTopology.DoldKan.N₁Γ₀ theorem N₁Γ₀_app (K : ChainComplex C ℕ) : N₁Γ₀.app K = (Γ₀.splitting K).toKaroubiNondegComplexIsoN₁.symm ≪≫ (toKaroubi _).mapIso (Γ₀NondegComplexIso K) := by ext1 dsimp [N₁Γ₀] erw [id_comp, comp_id, comp_id] rfl set_option linter.uppercaseLean3 false in #align algebraic_topology.dold_kan.N₁Γ₀_app AlgebraicTopology.DoldKan.N₁Γ₀_app theorem N₁Γ₀_hom_app (K : ChainComplex C ℕ) : N₁Γ₀.hom.app K = (Γ₀.splitting K).toKaroubiNondegComplexIsoN₁.inv ≫ (toKaroubi _).map (Γ₀NondegComplexIso K).hom := by change (N₁Γ₀.app K).hom = _ simp only [N₁Γ₀_app] rfl set_option linter.uppercaseLean3 false in #align algebraic_topology.dold_kan.N₁Γ₀_hom_app AlgebraicTopology.DoldKan.N₁Γ₀_hom_app theorem N₁Γ₀_inv_app (K : ChainComplex C ℕ) : N₁Γ₀.inv.app K = (toKaroubi _).map (Γ₀NondegComplexIso K).inv ≫ (Γ₀.splitting K).toKaroubiNondegComplexIsoN₁.hom := by change (N₁Γ₀.app K).inv = _ simp only [N₁Γ₀_app] rfl set_option linter.uppercaseLean3 false in #align algebraic_topology.dold_kan.N₁Γ₀_inv_app AlgebraicTopology.DoldKan.N₁Γ₀_inv_app @[simp] theorem N₁Γ₀_hom_app_f_f (K : ChainComplex C ℕ) (n : ℕ) : (N₁Γ₀.hom.app K).f.f n = (Γ₀.splitting K).toKaroubiNondegComplexIsoN₁.inv.f.f n := by rw [N₁Γ₀_hom_app] apply comp_id set_option linter.uppercaseLean3 false in #align algebraic_topology.dold_kan.N₁Γ₀_hom_app_f_f AlgebraicTopology.DoldKan.N₁Γ₀_hom_app_f_f @[simp]
Mathlib/AlgebraicTopology/DoldKan/GammaCompN.lean
113
116
theorem N₁Γ₀_inv_app_f_f (K : ChainComplex C ℕ) (n : ℕ) : (N₁Γ₀.inv.app K).f.f n = (Γ₀.splitting K).toKaroubiNondegComplexIsoN₁.hom.f.f n := by
rw [N₁Γ₀_inv_app] apply id_comp
import Mathlib.Algebra.Group.Support import Mathlib.Algebra.Order.Monoid.WithTop import Mathlib.Data.Nat.Cast.Field #align_import algebra.char_zero.lemmas from "leanprover-community/mathlib"@"acee671f47b8e7972a1eb6f4eed74b4b3abce829" open Function Set section AddMonoidWithOne variable {α M : Type*} [AddMonoidWithOne M] [CharZero M] {n : ℕ} instance CharZero.NeZero.two : NeZero (2 : M) := ⟨by have : ((2 : ℕ) : M) ≠ 0 := Nat.cast_ne_zero.2 (by decide) rwa [Nat.cast_two] at this⟩ #align char_zero.ne_zero.two CharZero.NeZero.two section variable {R : Type*} [NonAssocSemiring R] [NoZeroDivisors R] [CharZero R] {a : R} @[simp]
Mathlib/Algebra/CharZero/Lemmas.lean
88
89
theorem add_self_eq_zero {a : R} : a + a = 0 ↔ a = 0 := by
simp only [(two_mul a).symm, mul_eq_zero, two_ne_zero, false_or_iff]
import Mathlib.Data.Fintype.Order import Mathlib.Data.Set.Finite import Mathlib.Order.Category.FinPartOrd import Mathlib.Order.Category.LinOrd import Mathlib.CategoryTheory.Limits.Shapes.Images import Mathlib.CategoryTheory.Limits.Shapes.RegularMono import Mathlib.Data.Set.Subsingleton #align_import order.category.NonemptyFinLinOrd from "leanprover-community/mathlib"@"fa4a805d16a9cd9c96e0f8edeb57dc5a07af1a19" universe u v open CategoryTheory CategoryTheory.Limits class NonemptyFiniteLinearOrder (α : Type*) extends Fintype α, LinearOrder α where Nonempty : Nonempty α := by infer_instance #align nonempty_fin_lin_ord NonemptyFiniteLinearOrder attribute [instance] NonemptyFiniteLinearOrder.Nonempty instance (priority := 100) NonemptyFiniteLinearOrder.toBoundedOrder (α : Type*) [NonemptyFiniteLinearOrder α] : BoundedOrder α := Fintype.toBoundedOrder α #align nonempty_fin_lin_ord.to_bounded_order NonemptyFiniteLinearOrder.toBoundedOrder instance PUnit.nonemptyFiniteLinearOrder : NonemptyFiniteLinearOrder PUnit where #align punit.nonempty_fin_lin_ord PUnit.nonemptyFiniteLinearOrder instance Fin.nonemptyFiniteLinearOrder (n : ℕ) : NonemptyFiniteLinearOrder (Fin (n + 1)) where #align fin.nonempty_fin_lin_ord Fin.nonemptyFiniteLinearOrder instance ULift.nonemptyFiniteLinearOrder (α : Type u) [NonemptyFiniteLinearOrder α] : NonemptyFiniteLinearOrder (ULift.{v} α) := { LinearOrder.lift' Equiv.ulift (Equiv.injective _) with } #align ulift.nonempty_fin_lin_ord ULift.nonemptyFiniteLinearOrder instance (α : Type*) [NonemptyFiniteLinearOrder α] : NonemptyFiniteLinearOrder αᵒᵈ := { OrderDual.fintype α with } def NonemptyFinLinOrd := Bundled NonemptyFiniteLinearOrder set_option linter.uppercaseLean3 false in #align NonemptyFinLinOrd NonemptyFinLinOrd namespace NonemptyFinLinOrd instance : BundledHom.ParentProjection @NonemptyFiniteLinearOrder.toLinearOrder := ⟨⟩ deriving instance LargeCategory for NonemptyFinLinOrd -- Porting note: probably see https://github.com/leanprover-community/mathlib4/issues/5020 instance : ConcreteCategory NonemptyFinLinOrd := BundledHom.concreteCategory _ instance : CoeSort NonemptyFinLinOrd Type* := Bundled.coeSort def of (α : Type*) [NonemptyFiniteLinearOrder α] : NonemptyFinLinOrd := Bundled.of α set_option linter.uppercaseLean3 false in #align NonemptyFinLinOrd.of NonemptyFinLinOrd.of @[simp] theorem coe_of (α : Type*) [NonemptyFiniteLinearOrder α] : ↥(of α) = α := rfl set_option linter.uppercaseLean3 false in #align NonemptyFinLinOrd.coe_of NonemptyFinLinOrd.coe_of instance : Inhabited NonemptyFinLinOrd := ⟨of PUnit⟩ instance (α : NonemptyFinLinOrd) : NonemptyFiniteLinearOrder α := α.str instance hasForgetToLinOrd : HasForget₂ NonemptyFinLinOrd LinOrd := BundledHom.forget₂ _ _ set_option linter.uppercaseLean3 false in #align NonemptyFinLinOrd.has_forget_to_LinOrd NonemptyFinLinOrd.hasForgetToLinOrd instance hasForgetToFinPartOrd : HasForget₂ NonemptyFinLinOrd FinPartOrd where forget₂ := { obj := fun X => FinPartOrd.of X map := @fun X Y => id } set_option linter.uppercaseLean3 false in #align NonemptyFinLinOrd.has_forget_to_FinPartOrd NonemptyFinLinOrd.hasForgetToFinPartOrd @[simps] def Iso.mk {α β : NonemptyFinLinOrd.{u}} (e : α ≃o β) : α ≅ β where hom := (e : OrderHom _ _) inv := (e.symm : OrderHom _ _) hom_inv_id := by ext x exact e.symm_apply_apply x inv_hom_id := by ext x exact e.apply_symm_apply x set_option linter.uppercaseLean3 false in #align NonemptyFinLinOrd.iso.mk NonemptyFinLinOrd.Iso.mk @[simps] def dual : NonemptyFinLinOrd ⥤ NonemptyFinLinOrd where obj X := of Xᵒᵈ map := OrderHom.dual set_option linter.uppercaseLean3 false in #align NonemptyFinLinOrd.dual NonemptyFinLinOrd.dual @[simps functor inverse] def dualEquiv : NonemptyFinLinOrd ≌ NonemptyFinLinOrd where functor := dual inverse := dual unitIso := NatIso.ofComponents fun X => Iso.mk <| OrderIso.dualDual X counitIso := NatIso.ofComponents fun X => Iso.mk <| OrderIso.dualDual X set_option linter.uppercaseLean3 false in #align NonemptyFinLinOrd.dual_equiv NonemptyFinLinOrd.dualEquiv instance {A B : NonemptyFinLinOrd.{u}} : FunLike (A ⟶ B) A B where coe f := ⇑(show OrderHom A B from f) coe_injective' _ _ h := by ext x exact congr_fun h x -- porting note (#10670): this instance was not necessary in mathlib instance {A B : NonemptyFinLinOrd.{u}} : OrderHomClass (A ⟶ B) A B where map_rel f _ _ h := f.monotone h
Mathlib/Order/Category/NonemptyFinLinOrd.lean
150
163
theorem mono_iff_injective {A B : NonemptyFinLinOrd.{u}} (f : A ⟶ B) : Mono f ↔ Function.Injective f := by
refine ⟨?_, ConcreteCategory.mono_of_injective f⟩ intro intro a₁ a₂ h let X := NonemptyFinLinOrd.of (ULift (Fin 1)) let g₁ : X ⟶ A := ⟨fun _ => a₁, fun _ _ _ => by rfl⟩ let g₂ : X ⟶ A := ⟨fun _ => a₂, fun _ _ _ => by rfl⟩ change g₁ (ULift.up (0 : Fin 1)) = g₂ (ULift.up (0 : Fin 1)) have eq : g₁ ≫ f = g₂ ≫ f := by ext exact h rw [cancel_mono] at eq rw [eq]
import Mathlib.Algebra.Algebra.Tower import Mathlib.Algebra.MvPolynomial.Basic #align_import ring_theory.mv_polynomial.tower from "leanprover-community/mathlib"@"bb168510ef455e9280a152e7f31673cabd3d7496" variable (R A B : Type*) {σ : Type*} namespace MvPolynomial section CommSemiring variable [CommSemiring R] [CommSemiring A] [CommSemiring B] variable [Algebra R A] [Algebra A B] [Algebra R B] [IsScalarTower R A B] variable {R A}
Mathlib/RingTheory/MvPolynomial/Tower.lean
48
53
theorem aeval_algebraMap_apply (x : σ → A) (p : MvPolynomial σ R) : aeval (algebraMap A B ∘ x) p = algebraMap A B (MvPolynomial.aeval x p) := by
rw [aeval_def, aeval_def, ← coe_eval₂Hom, ← coe_eval₂Hom, map_eval₂Hom, ← IsScalarTower.algebraMap_eq] -- Porting note: added simp only [Function.comp]
import Mathlib.Algebra.Polynomial.Degree.TrailingDegree import Mathlib.Algebra.Polynomial.EraseLead import Mathlib.Algebra.Polynomial.Eval #align_import data.polynomial.reverse from "leanprover-community/mathlib"@"44de64f183393284a16016dfb2a48ac97382f2bd" namespace Polynomial open Polynomial Finsupp Finset open Polynomial section Semiring variable {R : Type*} [Semiring R] {f : R[X]} def revAtFun (N i : ℕ) : ℕ := ite (i ≤ N) (N - i) i #align polynomial.rev_at_fun Polynomial.revAtFun theorem revAtFun_invol {N i : ℕ} : revAtFun N (revAtFun N i) = i := by unfold revAtFun split_ifs with h j · exact tsub_tsub_cancel_of_le h · exfalso apply j exact Nat.sub_le N i · rfl #align polynomial.rev_at_fun_invol Polynomial.revAtFun_invol theorem revAtFun_inj {N : ℕ} : Function.Injective (revAtFun N) := by intro a b hab rw [← @revAtFun_invol N a, hab, revAtFun_invol] #align polynomial.rev_at_fun_inj Polynomial.revAtFun_inj def revAt (N : ℕ) : Function.Embedding ℕ ℕ where toFun i := ite (i ≤ N) (N - i) i inj' := revAtFun_inj #align polynomial.rev_at Polynomial.revAt @[simp] theorem revAtFun_eq (N i : ℕ) : revAtFun N i = revAt N i := rfl #align polynomial.rev_at_fun_eq Polynomial.revAtFun_eq @[simp] theorem revAt_invol {N i : ℕ} : (revAt N) (revAt N i) = i := revAtFun_invol #align polynomial.rev_at_invol Polynomial.revAt_invol @[simp] theorem revAt_le {N i : ℕ} (H : i ≤ N) : revAt N i = N - i := if_pos H #align polynomial.rev_at_le Polynomial.revAt_le lemma revAt_eq_self_of_lt {N i : ℕ} (h : N < i) : revAt N i = i := by simp [revAt, Nat.not_le.mpr h]
Mathlib/Algebra/Polynomial/Reverse.lean
82
88
theorem revAt_add {N O n o : ℕ} (hn : n ≤ N) (ho : o ≤ O) : revAt (N + O) (n + o) = revAt N n + revAt O o := by
rcases Nat.le.dest hn with ⟨n', rfl⟩ rcases Nat.le.dest ho with ⟨o', rfl⟩ repeat' rw [revAt_le (le_add_right rfl.le)] rw [add_assoc, add_left_comm n' o, ← add_assoc, revAt_le (le_add_right rfl.le)] repeat' rw [add_tsub_cancel_left]
import Mathlib.Data.Real.Basic import Mathlib.Combinatorics.Pigeonhole import Mathlib.Algebra.Order.EuclideanAbsoluteValue #align_import number_theory.class_number.admissible_absolute_value from "leanprover-community/mathlib"@"f7fc89d5d5ff1db2d1242c7bb0e9062ce47ef47c" local infixl:50 " ≺ " => EuclideanDomain.r namespace AbsoluteValue variable {R : Type*} [EuclideanDomain R] variable (abv : AbsoluteValue R ℤ) structure IsAdmissible extends IsEuclidean abv where protected card : ℝ → ℕ exists_partition' : ∀ (n : ℕ) {ε : ℝ} (_ : 0 < ε) {b : R} (_ : b ≠ 0) (A : Fin n → R), ∃ t : Fin n → Fin (card ε), ∀ i₀ i₁, t i₀ = t i₁ → (abv (A i₁ % b - A i₀ % b) : ℝ) < abv b • ε #align absolute_value.is_admissible AbsoluteValue.IsAdmissible -- Porting note: no docstrings for IsAdmissible attribute [nolint docBlame] IsAdmissible.card namespace IsAdmissible variable {abv} theorem exists_partition {ι : Type*} [Finite ι] {ε : ℝ} (hε : 0 < ε) {b : R} (hb : b ≠ 0) (A : ι → R) (h : abv.IsAdmissible) : ∃ t : ι → Fin (h.card ε), ∀ i₀ i₁, t i₀ = t i₁ → (abv (A i₁ % b - A i₀ % b) : ℝ) < abv b • ε := by rcases Finite.exists_equiv_fin ι with ⟨n, ⟨e⟩⟩ obtain ⟨t, ht⟩ := h.exists_partition' n hε hb (A ∘ e.symm) refine ⟨t ∘ e, fun i₀ i₁ h ↦ ?_⟩ convert (config := {transparency := .default}) ht (e i₀) (e i₁) h <;> simp only [e.symm_apply_apply] #align absolute_value.is_admissible.exists_partition AbsoluteValue.IsAdmissible.exists_partition theorem exists_approx_aux (n : ℕ) (h : abv.IsAdmissible) : ∀ {ε : ℝ} (_hε : 0 < ε) {b : R} (_hb : b ≠ 0) (A : Fin (h.card ε ^ n).succ → Fin n → R), ∃ i₀ i₁, i₀ ≠ i₁ ∧ ∀ k, (abv (A i₁ k % b - A i₀ k % b) : ℝ) < abv b • ε := by haveI := Classical.decEq R induction' n with n ih · intro ε _hε b _hb A refine ⟨0, 1, ?_, ?_⟩ · simp rintro ⟨i, ⟨⟩⟩ intro ε hε b hb A let M := h.card ε -- By the "nicer" pigeonhole principle, we can find a collection `s` -- of more than `M^n` remainders where the first components lie close together: obtain ⟨s, s_inj, hs⟩ : ∃ s : Fin (M ^ n).succ → Fin (M ^ n.succ).succ, Function.Injective s ∧ ∀ i₀ i₁, (abv (A (s i₁) 0 % b - A (s i₀) 0 % b) : ℝ) < abv b • ε := by -- We can partition the `A`s into `M` subsets where -- the first components lie close together: obtain ⟨t, ht⟩ : ∃ t : Fin (M ^ n.succ).succ → Fin M, ∀ i₀ i₁, t i₀ = t i₁ → (abv (A i₁ 0 % b - A i₀ 0 % b) : ℝ) < abv b • ε := h.exists_partition hε hb fun x ↦ A x 0 -- Since the `M` subsets contain more than `M * M^n` elements total, -- there must be a subset that contains more than `M^n` elements. obtain ⟨s, hs⟩ := Fintype.exists_lt_card_fiber_of_mul_lt_card (f := t) (by simpa only [Fintype.card_fin, pow_succ'] using Nat.lt_succ_self (M ^ n.succ)) refine ⟨fun i ↦ (Finset.univ.filter fun x ↦ t x = s).toList.get <| i.castLE ?_, fun i j h ↦ ?_, fun i₀ i₁ ↦ ht _ _ ?_⟩ · rwa [Finset.length_toList] · simpa [(Finset.nodup_toList _).get_inj_iff] using h · have : ∀ i, t ((Finset.univ.filter fun x ↦ t x = s).toList.get i) = s := fun i ↦ (Finset.mem_filter.mp (Finset.mem_toList.mp (List.get_mem _ i i.2))).2 simp [this] -- Since `s` is large enough, there are two elements of `A ∘ s` -- where the second components lie close together. obtain ⟨k₀, k₁, hk, h⟩ := ih hε hb fun x ↦ Fin.tail (A (s x)) refine ⟨s k₀, s k₁, fun h ↦ hk (s_inj h), fun i ↦ Fin.cases ?_ (fun i ↦ ?_) i⟩ · exact hs k₀ k₁ · exact h i #align absolute_value.is_admissible.exists_approx_aux AbsoluteValue.IsAdmissible.exists_approx_aux
Mathlib/NumberTheory/ClassNumber/AdmissibleAbsoluteValue.lean
117
123
theorem exists_approx {ι : Type*} [Fintype ι] {ε : ℝ} (hε : 0 < ε) {b : R} (hb : b ≠ 0) (h : abv.IsAdmissible) (A : Fin (h.card ε ^ Fintype.card ι).succ → ι → R) : ∃ i₀ i₁, i₀ ≠ i₁ ∧ ∀ k, (abv (A i₁ k % b - A i₀ k % b) : ℝ) < abv b • ε := by
let e := Fintype.equivFin ι obtain ⟨i₀, i₁, ne, h⟩ := h.exists_approx_aux (Fintype.card ι) hε hb fun x y ↦ A x (e.symm y) refine ⟨i₀, i₁, ne, fun k ↦ ?_⟩ convert h (e k) <;> simp only [e.symm_apply_apply]
import Mathlib.Analysis.Calculus.FDeriv.Basic #align_import analysis.calculus.fderiv.restrict_scalars from "leanprover-community/mathlib"@"e3fb84046afd187b710170887195d50bada934ee" open Filter Asymptotics ContinuousLinearMap Set Metric open scoped Classical open Topology NNReal Filter Asymptotics ENNReal noncomputable section section RestrictScalars variable (𝕜 : Type*) [NontriviallyNormedField 𝕜] variable {𝕜' : Type*} [NontriviallyNormedField 𝕜'] [NormedAlgebra 𝕜 𝕜'] variable {E : Type*} [NormedAddCommGroup E] [NormedSpace 𝕜 E] [NormedSpace 𝕜' E] variable [IsScalarTower 𝕜 𝕜' E] variable {F : Type*} [NormedAddCommGroup F] [NormedSpace 𝕜 F] [NormedSpace 𝕜' F] variable [IsScalarTower 𝕜 𝕜' F] variable {f : E → F} {f' : E →L[𝕜'] F} {s : Set E} {x : E} @[fun_prop] theorem HasStrictFDerivAt.restrictScalars (h : HasStrictFDerivAt f f' x) : HasStrictFDerivAt f (f'.restrictScalars 𝕜) x := h #align has_strict_fderiv_at.restrict_scalars HasStrictFDerivAt.restrictScalars theorem HasFDerivAtFilter.restrictScalars {L} (h : HasFDerivAtFilter f f' x L) : HasFDerivAtFilter f (f'.restrictScalars 𝕜) x L := .of_isLittleO h.1 #align has_fderiv_at_filter.restrict_scalars HasFDerivAtFilter.restrictScalars @[fun_prop] theorem HasFDerivAt.restrictScalars (h : HasFDerivAt f f' x) : HasFDerivAt f (f'.restrictScalars 𝕜) x := .of_isLittleO h.1 #align has_fderiv_at.restrict_scalars HasFDerivAt.restrictScalars @[fun_prop] theorem HasFDerivWithinAt.restrictScalars (h : HasFDerivWithinAt f f' s x) : HasFDerivWithinAt f (f'.restrictScalars 𝕜) s x := .of_isLittleO h.1 #align has_fderiv_within_at.restrict_scalars HasFDerivWithinAt.restrictScalars @[fun_prop] theorem DifferentiableAt.restrictScalars (h : DifferentiableAt 𝕜' f x) : DifferentiableAt 𝕜 f x := (h.hasFDerivAt.restrictScalars 𝕜).differentiableAt #align differentiable_at.restrict_scalars DifferentiableAt.restrictScalars @[fun_prop] theorem DifferentiableWithinAt.restrictScalars (h : DifferentiableWithinAt 𝕜' f s x) : DifferentiableWithinAt 𝕜 f s x := (h.hasFDerivWithinAt.restrictScalars 𝕜).differentiableWithinAt #align differentiable_within_at.restrict_scalars DifferentiableWithinAt.restrictScalars @[fun_prop] theorem DifferentiableOn.restrictScalars (h : DifferentiableOn 𝕜' f s) : DifferentiableOn 𝕜 f s := fun x hx => (h x hx).restrictScalars 𝕜 #align differentiable_on.restrict_scalars DifferentiableOn.restrictScalars @[fun_prop] theorem Differentiable.restrictScalars (h : Differentiable 𝕜' f) : Differentiable 𝕜 f := fun x => (h x).restrictScalars 𝕜 #align differentiable.restrict_scalars Differentiable.restrictScalars @[fun_prop] theorem HasFDerivWithinAt.of_restrictScalars {g' : E →L[𝕜] F} (h : HasFDerivWithinAt f g' s x) (H : f'.restrictScalars 𝕜 = g') : HasFDerivWithinAt f f' s x := by rw [← H] at h exact .of_isLittleO h.1 #align has_fderiv_within_at_of_restrict_scalars HasFDerivWithinAt.of_restrictScalars @[fun_prop]
Mathlib/Analysis/Calculus/FDeriv/RestrictScalars.lean
99
102
theorem hasFDerivAt_of_restrictScalars {g' : E →L[𝕜] F} (h : HasFDerivAt f g' x) (H : f'.restrictScalars 𝕜 = g') : HasFDerivAt f f' x := by
rw [← H] at h exact .of_isLittleO h.1
import Mathlib.LinearAlgebra.TensorProduct.Tower import Mathlib.Algebra.DirectSum.Module #align_import linear_algebra.direct_sum.tensor_product from "leanprover-community/mathlib"@"9b9d125b7be0930f564a68f1d73ace10cf46064d" suppress_compilation universe u v₁ v₂ w₁ w₁' w₂ w₂' section Ring namespace TensorProduct open TensorProduct open DirectSum open LinearMap attribute [local ext] TensorProduct.ext variable (R : Type u) [CommSemiring R] (S) [Semiring S] [Algebra R S] variable {ι₁ : Type v₁} {ι₂ : Type v₂} variable [DecidableEq ι₁] [DecidableEq ι₂] variable (M₁ : ι₁ → Type w₁) (M₁' : Type w₁') (M₂ : ι₂ → Type w₂) (M₂' : Type w₂') variable [∀ i₁, AddCommMonoid (M₁ i₁)] [AddCommMonoid M₁'] variable [∀ i₂, AddCommMonoid (M₂ i₂)] [AddCommMonoid M₂'] variable [∀ i₁, Module R (M₁ i₁)] [Module R M₁'] [∀ i₂, Module R (M₂ i₂)] [Module R M₂'] variable [∀ i₁, Module S (M₁ i₁)] [∀ i₁, IsScalarTower R S (M₁ i₁)] protected def directSum : ((⨁ i₁, M₁ i₁) ⊗[R] ⨁ i₂, M₂ i₂) ≃ₗ[S] ⨁ i : ι₁ × ι₂, M₁ i.1 ⊗[R] M₂ i.2 := by -- Porting note: entirely rewritten to allow unification to happen one step at a time refine LinearEquiv.ofLinear (R := S) (R₂ := S) ?toFun ?invFun ?left ?right · refine AlgebraTensorModule.lift ?_ refine DirectSum.toModule S _ _ fun i₁ => ?_ refine LinearMap.flip ?_ refine DirectSum.toModule R _ _ fun i₂ => LinearMap.flip <| ?_ refine AlgebraTensorModule.curry ?_ exact DirectSum.lof S (ι₁ × ι₂) (fun i => M₁ i.1 ⊗[R] M₂ i.2) (i₁, i₂) · refine DirectSum.toModule S _ _ fun i => ?_ exact AlgebraTensorModule.map (DirectSum.lof S _ M₁ i.1) (DirectSum.lof R _ M₂ i.2) · refine DirectSum.linearMap_ext S fun ⟨i₁, i₂⟩ => ?_ refine TensorProduct.AlgebraTensorModule.ext fun m₁ m₂ => ?_ -- Porting note: seems much nicer than the `repeat` lean 3 proof. simp only [coe_comp, Function.comp_apply, toModule_lof, AlgebraTensorModule.map_tmul, AlgebraTensorModule.lift_apply, lift.tmul, coe_restrictScalars, flip_apply, AlgebraTensorModule.curry_apply, curry_apply, id_comp] · -- `(_)` prevents typeclass search timing out on problems that can be solved immediately by -- unification apply TensorProduct.AlgebraTensorModule.curry_injective refine DirectSum.linearMap_ext _ fun i₁ => ?_ refine LinearMap.ext fun x₁ => ?_ refine DirectSum.linearMap_ext _ fun i₂ => ?_ refine LinearMap.ext fun x₂ => ?_ -- Porting note: seems much nicer than the `repeat` lean 3 proof. simp only [coe_comp, Function.comp_apply, AlgebraTensorModule.curry_apply, curry_apply, coe_restrictScalars, AlgebraTensorModule.lift_apply, lift.tmul, toModule_lof, flip_apply, AlgebraTensorModule.map_tmul, id_coe, id_eq] #align tensor_product.direct_sum TensorProduct.directSum def directSumLeft : (⨁ i₁, M₁ i₁) ⊗[R] M₂' ≃ₗ[R] ⨁ i, M₁ i ⊗[R] M₂' := LinearEquiv.ofLinear (lift <| DirectSum.toModule R _ _ fun i => (mk R _ _).compr₂ <| DirectSum.lof R ι₁ (fun i => M₁ i ⊗[R] M₂') _) (DirectSum.toModule R _ _ fun i => rTensor _ (DirectSum.lof R ι₁ _ _)) (DirectSum.linearMap_ext R fun i => TensorProduct.ext <| LinearMap.ext₂ fun m₁ m₂ => by dsimp only [comp_apply, compr₂_apply, id_apply, mk_apply] simp_rw [DirectSum.toModule_lof, rTensor_tmul, lift.tmul, DirectSum.toModule_lof, compr₂_apply, mk_apply]) (TensorProduct.ext <| DirectSum.linearMap_ext R fun i => LinearMap.ext₂ fun m₁ m₂ => by dsimp only [comp_apply, compr₂_apply, id_apply, mk_apply] simp_rw [lift.tmul, DirectSum.toModule_lof, compr₂_apply, mk_apply, DirectSum.toModule_lof, rTensor_tmul]) #align tensor_product.direct_sum_left TensorProduct.directSumLeft def directSumRight : (M₁' ⊗[R] ⨁ i, M₂ i) ≃ₗ[R] ⨁ i, M₁' ⊗[R] M₂ i := TensorProduct.comm R _ _ ≪≫ₗ directSumLeft R M₂ M₁' ≪≫ₗ DFinsupp.mapRange.linearEquiv fun _ => TensorProduct.comm R _ _ #align tensor_product.direct_sum_right TensorProduct.directSumRight variable {M₁ M₁' M₂ M₂'} @[simp]
Mathlib/LinearAlgebra/DirectSum/TensorProduct.lean
150
153
theorem directSum_lof_tmul_lof (i₁ : ι₁) (m₁ : M₁ i₁) (i₂ : ι₂) (m₂ : M₂ i₂) : TensorProduct.directSum R S M₁ M₂ (DirectSum.lof S ι₁ M₁ i₁ m₁ ⊗ₜ DirectSum.lof R ι₂ M₂ i₂ m₂) = DirectSum.lof S (ι₁ × ι₂) (fun i => M₁ i.1 ⊗[R] M₂ i.2) (i₁, i₂) (m₁ ⊗ₜ m₂) := by
simp [TensorProduct.directSum]
import Mathlib.Algebra.CharP.Invertible import Mathlib.Algebra.Order.Invertible import Mathlib.Algebra.Order.Module.OrderedSMul import Mathlib.Algebra.Order.Group.Instances import Mathlib.LinearAlgebra.AffineSpace.Slope import Mathlib.LinearAlgebra.AffineSpace.Midpoint import Mathlib.Tactic.FieldSimp #align_import linear_algebra.affine_space.ordered from "leanprover-community/mathlib"@"78261225eb5cedc61c5c74ecb44e5b385d13b733" open AffineMap variable {k E PE : Type*} section OrderedRing variable [OrderedRing k] [OrderedAddCommGroup E] [Module k E] [OrderedSMul k E] variable {a a' b b' : E} {r r' : k} theorem lineMap_mono_left (ha : a ≤ a') (hr : r ≤ 1) : lineMap a b r ≤ lineMap a' b r := by simp only [lineMap_apply_module] exact add_le_add_right (smul_le_smul_of_nonneg_left ha (sub_nonneg.2 hr)) _ #align line_map_mono_left lineMap_mono_left
Mathlib/LinearAlgebra/AffineSpace/Ordered.lean
57
59
theorem lineMap_strict_mono_left (ha : a < a') (hr : r < 1) : lineMap a b r < lineMap a' b r := by
simp only [lineMap_apply_module] exact add_lt_add_right (smul_lt_smul_of_pos_left ha (sub_pos.2 hr)) _
import Mathlib.Algebra.Category.GroupCat.Abelian import Mathlib.CategoryTheory.Limits.Shapes.Images #align_import algebra.category.Group.images from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a" open CategoryTheory open CategoryTheory.Limits universe u namespace AddCommGroupCat set_option linter.uppercaseLean3 false -- Note that because `injective_of_mono` is currently only proved in `Type 0`, -- we restrict to the lowest universe here for now. variable {G H : AddCommGroupCat.{0}} (f : G ⟶ H) attribute [local ext] Subtype.ext_val section -- implementation details of `IsImage` for `AddCommGroupCat`; use the API, not these def image : AddCommGroupCat := AddCommGroupCat.of (AddMonoidHom.range f) #align AddCommGroup.image AddCommGroupCat.image def image.ι : image f ⟶ H := f.range.subtype #align AddCommGroup.image.ι AddCommGroupCat.image.ι instance : Mono (image.ι f) := ConcreteCategory.mono_of_injective (image.ι f) Subtype.val_injective def factorThruImage : G ⟶ image f := f.rangeRestrict #align AddCommGroup.factor_thru_image AddCommGroupCat.factorThruImage theorem image.fac : factorThruImage f ≫ image.ι f = f := by ext rfl #align AddCommGroup.image.fac AddCommGroupCat.image.fac attribute [local simp] image.fac variable {f} noncomputable def image.lift (F' : MonoFactorisation f) : image f ⟶ F'.I where toFun := (fun x => F'.e (Classical.indefiniteDescription _ x.2).1 : image f → F'.I) map_zero' := by haveI := F'.m_mono apply injective_of_mono F'.m change (F'.e ≫ F'.m) _ = _ rw [F'.fac, AddMonoidHom.map_zero] exact (Classical.indefiniteDescription (fun y => f y = 0) _).2 map_add' := by intro x y haveI := F'.m_mono apply injective_of_mono F'.m rw [AddMonoidHom.map_add] change (F'.e ≫ F'.m) _ = (F'.e ≫ F'.m) _ + (F'.e ≫ F'.m) _ rw [F'.fac] rw [(Classical.indefiniteDescription (fun z => f z = _) _).2] rw [(Classical.indefiniteDescription (fun z => f z = _) _).2] rw [(Classical.indefiniteDescription (fun z => f z = _) _).2] rfl #align AddCommGroup.image.lift AddCommGroupCat.image.lift
Mathlib/Algebra/Category/GroupCat/Images.lean
87
91
theorem image.lift_fac (F' : MonoFactorisation f) : image.lift F' ≫ F'.m = image.ι f := by
ext x change (F'.e ≫ F'.m) _ = _ rw [F'.fac, (Classical.indefiniteDescription _ x.2).2] rfl
import Mathlib.LinearAlgebra.QuadraticForm.TensorProduct import Mathlib.LinearAlgebra.CliffordAlgebra.Conjugation import Mathlib.LinearAlgebra.TensorProduct.Opposite import Mathlib.RingTheory.TensorProduct.Basic variable {R A V : Type*} variable [CommRing R] [CommRing A] [AddCommGroup V] variable [Algebra R A] [Module R V] [Module A V] [IsScalarTower R A V] variable [Invertible (2 : R)] open scoped TensorProduct namespace CliffordAlgebra variable (A) -- `noncomputable` is a performance workaround for mathlib4#7103 noncomputable def ofBaseChangeAux (Q : QuadraticForm R V) : CliffordAlgebra Q →ₐ[R] CliffordAlgebra (Q.baseChange A) := CliffordAlgebra.lift Q <| by refine ⟨(ι (Q.baseChange A)).restrictScalars R ∘ₗ TensorProduct.mk R A V 1, fun v => ?_⟩ refine (CliffordAlgebra.ι_sq_scalar (Q.baseChange A) (1 ⊗ₜ v)).trans ?_ rw [QuadraticForm.baseChange_tmul, one_mul, ← Algebra.algebraMap_eq_smul_one, ← IsScalarTower.algebraMap_apply] @[simp] theorem ofBaseChangeAux_ι (Q : QuadraticForm R V) (v : V) : ofBaseChangeAux A Q (ι Q v) = ι (Q.baseChange A) (1 ⊗ₜ v) := CliffordAlgebra.lift_ι_apply _ _ v -- `noncomputable` is a performance workaround for mathlib4#7103 noncomputable def ofBaseChange (Q : QuadraticForm R V) : A ⊗[R] CliffordAlgebra Q →ₐ[A] CliffordAlgebra (Q.baseChange A) := Algebra.TensorProduct.lift (Algebra.ofId _ _) (ofBaseChangeAux A Q) fun _a _x => Algebra.commutes _ _ @[simp] theorem ofBaseChange_tmul_ι (Q : QuadraticForm R V) (z : A) (v : V) : ofBaseChange A Q (z ⊗ₜ ι Q v) = ι (Q.baseChange A) (z ⊗ₜ v) := by show algebraMap _ _ z * ofBaseChangeAux A Q (ι Q v) = ι (Q.baseChange A) (z ⊗ₜ[R] v) rw [ofBaseChangeAux_ι, ← Algebra.smul_def, ← map_smul, TensorProduct.smul_tmul', smul_eq_mul, mul_one] @[simp] theorem ofBaseChange_tmul_one (Q : QuadraticForm R V) (z : A) : ofBaseChange A Q (z ⊗ₜ 1) = algebraMap _ _ z := by show algebraMap _ _ z * ofBaseChangeAux A Q 1 = _ rw [map_one, mul_one] -- `noncomputable` is a performance workaround for mathlib4#7103 noncomputable def toBaseChange (Q : QuadraticForm R V) : CliffordAlgebra (Q.baseChange A) →ₐ[A] A ⊗[R] CliffordAlgebra Q := CliffordAlgebra.lift _ <| by refine ⟨TensorProduct.AlgebraTensorModule.map (LinearMap.id : A →ₗ[A] A) (ι Q), ?_⟩ letI : Invertible (2 : A) := (Invertible.map (algebraMap R A) 2).copy 2 (map_ofNat _ _).symm letI : Invertible (2 : A ⊗[R] CliffordAlgebra Q) := (Invertible.map (algebraMap R _) 2).copy 2 (map_ofNat _ _).symm suffices hpure_tensor : ∀ v w, (1 * 1) ⊗ₜ[R] (ι Q v * ι Q w) + (1 * 1) ⊗ₜ[R] (ι Q w * ι Q v) = QuadraticForm.polarBilin (Q.baseChange A) (1 ⊗ₜ[R] v) (1 ⊗ₜ[R] w) ⊗ₜ[R] 1 by -- the crux is that by converting to a statement about linear maps instead of quadratic forms, -- we then have access to all the partially-applied `ext` lemmas. rw [CliffordAlgebra.forall_mul_self_eq_iff (isUnit_of_invertible _)] refine TensorProduct.AlgebraTensorModule.curry_injective ?_ ext v w exact hpure_tensor v w intros v w rw [← TensorProduct.tmul_add, CliffordAlgebra.ι_mul_ι_add_swap, QuadraticForm.polarBilin_baseChange, LinearMap.BilinForm.baseChange_tmul, one_mul, TensorProduct.smul_tmul, Algebra.algebraMap_eq_smul_one, QuadraticForm.polarBilin_apply_apply] @[simp] theorem toBaseChange_ι (Q : QuadraticForm R V) (z : A) (v : V) : toBaseChange A Q (ι (Q.baseChange A) (z ⊗ₜ v)) = z ⊗ₜ ι Q v := CliffordAlgebra.lift_ι_apply _ _ _ theorem toBaseChange_comp_involute (Q : QuadraticForm R V) : (toBaseChange A Q).comp (involute : CliffordAlgebra (Q.baseChange A) →ₐ[A] _) = (Algebra.TensorProduct.map (AlgHom.id _ _) involute).comp (toBaseChange A Q) := by ext v show toBaseChange A Q (involute (ι (Q.baseChange A) (1 ⊗ₜ[R] v))) = (Algebra.TensorProduct.map (AlgHom.id _ _) involute : A ⊗[R] CliffordAlgebra Q →ₐ[A] _) (toBaseChange A Q (ι (Q.baseChange A) (1 ⊗ₜ[R] v))) rw [toBaseChange_ι, involute_ι, map_neg (toBaseChange A Q), toBaseChange_ι, Algebra.TensorProduct.map_tmul, AlgHom.id_apply, involute_ι, TensorProduct.tmul_neg] theorem toBaseChange_involute (Q : QuadraticForm R V) (x : CliffordAlgebra (Q.baseChange A)) : toBaseChange A Q (involute x) = TensorProduct.map LinearMap.id (involute.toLinearMap) (toBaseChange A Q x) := DFunLike.congr_fun (toBaseChange_comp_involute A Q) x open MulOpposite
Mathlib/LinearAlgebra/CliffordAlgebra/BaseChange.lean
124
137
theorem toBaseChange_comp_reverseOp (Q : QuadraticForm R V) : (toBaseChange A Q).op.comp reverseOp = ((Algebra.TensorProduct.opAlgEquiv R A A (CliffordAlgebra Q)).toAlgHom.comp <| (Algebra.TensorProduct.map (AlgEquiv.toOpposite A A).toAlgHom (reverseOp (Q := Q))).comp (toBaseChange A Q)) := by
ext v show op (toBaseChange A Q (reverse (ι (Q.baseChange A) (1 ⊗ₜ[R] v)))) = Algebra.TensorProduct.opAlgEquiv R A A (CliffordAlgebra Q) (Algebra.TensorProduct.map (AlgEquiv.toOpposite A A).toAlgHom (reverseOp (Q := Q)) (toBaseChange A Q (ι (Q.baseChange A) (1 ⊗ₜ[R] v)))) rw [toBaseChange_ι, reverse_ι, toBaseChange_ι, Algebra.TensorProduct.map_tmul, Algebra.TensorProduct.opAlgEquiv_tmul, reverseOp_ι] rfl
import Mathlib.SetTheory.Game.Basic import Mathlib.Tactic.NthRewrite #align_import set_theory.game.impartial from "leanprover-community/mathlib"@"2e0975f6a25dd3fbfb9e41556a77f075f6269748" universe u namespace SetTheory open scoped PGame namespace PGame def ImpartialAux : PGame → Prop | G => (G ≈ -G) ∧ (∀ i, ImpartialAux (G.moveLeft i)) ∧ ∀ j, ImpartialAux (G.moveRight j) termination_by G => G -- Porting note: Added `termination_by` #align pgame.impartial_aux SetTheory.PGame.ImpartialAux theorem impartialAux_def {G : PGame} : G.ImpartialAux ↔ (G ≈ -G) ∧ (∀ i, ImpartialAux (G.moveLeft i)) ∧ ∀ j, ImpartialAux (G.moveRight j) := by rw [ImpartialAux] #align pgame.impartial_aux_def SetTheory.PGame.impartialAux_def class Impartial (G : PGame) : Prop where out : ImpartialAux G #align pgame.impartial SetTheory.PGame.Impartial theorem impartial_iff_aux {G : PGame} : G.Impartial ↔ G.ImpartialAux := ⟨fun h => h.1, fun h => ⟨h⟩⟩ #align pgame.impartial_iff_aux SetTheory.PGame.impartial_iff_aux theorem impartial_def {G : PGame} : G.Impartial ↔ (G ≈ -G) ∧ (∀ i, Impartial (G.moveLeft i)) ∧ ∀ j, Impartial (G.moveRight j) := by simpa only [impartial_iff_aux] using impartialAux_def #align pgame.impartial_def SetTheory.PGame.impartial_def namespace Impartial instance impartial_zero : Impartial 0 := by rw [impartial_def]; dsimp; simp #align pgame.impartial.impartial_zero SetTheory.PGame.Impartial.impartial_zero instance impartial_star : Impartial star := by rw [impartial_def]; simpa using Impartial.impartial_zero #align pgame.impartial.impartial_star SetTheory.PGame.Impartial.impartial_star theorem neg_equiv_self (G : PGame) [h : G.Impartial] : G ≈ -G := (impartial_def.1 h).1 #align pgame.impartial.neg_equiv_self SetTheory.PGame.Impartial.neg_equiv_self -- Porting note: Changed `-⟦G⟧` to `-(⟦G⟧ : Quotient setoid)` @[simp] theorem mk'_neg_equiv_self (G : PGame) [G.Impartial] : -(⟦G⟧ : Quotient setoid) = ⟦G⟧ := Quot.sound (Equiv.symm (neg_equiv_self G)) #align pgame.impartial.mk_neg_equiv_self SetTheory.PGame.Impartial.mk'_neg_equiv_self instance moveLeft_impartial {G : PGame} [h : G.Impartial] (i : G.LeftMoves) : (G.moveLeft i).Impartial := (impartial_def.1 h).2.1 i #align pgame.impartial.move_left_impartial SetTheory.PGame.Impartial.moveLeft_impartial instance moveRight_impartial {G : PGame} [h : G.Impartial] (j : G.RightMoves) : (G.moveRight j).Impartial := (impartial_def.1 h).2.2 j #align pgame.impartial.move_right_impartial SetTheory.PGame.Impartial.moveRight_impartial theorem impartial_congr : ∀ {G H : PGame} (_ : G ≡r H) [G.Impartial], H.Impartial | G, H => fun e => by intro h exact impartial_def.2 ⟨Equiv.trans e.symm.equiv (Equiv.trans (neg_equiv_self G) (neg_equiv_neg_iff.2 e.equiv)), fun i => impartial_congr (e.moveLeftSymm i), fun j => impartial_congr (e.moveRightSymm j)⟩ termination_by G H => (G, H) #align pgame.impartial.impartial_congr SetTheory.PGame.Impartial.impartial_congr instance impartial_add : ∀ (G H : PGame) [G.Impartial] [H.Impartial], (G + H).Impartial | G, H, _, _ => by rw [impartial_def] refine ⟨Equiv.trans (add_congr (neg_equiv_self G) (neg_equiv_self _)) (Equiv.symm (negAddRelabelling _ _).equiv), fun k => ?_, fun k => ?_⟩ · apply leftMoves_add_cases k all_goals intro i; simp only [add_moveLeft_inl, add_moveLeft_inr] apply impartial_add · apply rightMoves_add_cases k all_goals intro i; simp only [add_moveRight_inl, add_moveRight_inr] apply impartial_add termination_by G H => (G, H) #align pgame.impartial.impartial_add SetTheory.PGame.Impartial.impartial_add instance impartial_neg : ∀ (G : PGame) [G.Impartial], (-G).Impartial | G, _ => by rw [impartial_def] refine ⟨?_, fun i => ?_, fun i => ?_⟩ · rw [neg_neg] exact Equiv.symm (neg_equiv_self G) · rw [moveLeft_neg'] apply impartial_neg · rw [moveRight_neg'] apply impartial_neg termination_by G => G #align pgame.impartial.impartial_neg SetTheory.PGame.Impartial.impartial_neg variable (G : PGame) [Impartial G] theorem nonpos : ¬0 < G := fun h => by have h' := neg_lt_neg_iff.2 h rw [neg_zero, lt_congr_left (Equiv.symm (neg_equiv_self G))] at h' exact (h.trans h').false #align pgame.impartial.nonpos SetTheory.PGame.Impartial.nonpos theorem nonneg : ¬G < 0 := fun h => by have h' := neg_lt_neg_iff.2 h rw [neg_zero, lt_congr_right (Equiv.symm (neg_equiv_self G))] at h' exact (h.trans h').false #align pgame.impartial.nonneg SetTheory.PGame.Impartial.nonneg
Mathlib/SetTheory/Game/Impartial.lean
137
142
theorem equiv_or_fuzzy_zero : (G ≈ 0) ∨ G ‖ 0 := by
rcases lt_or_equiv_or_gt_or_fuzzy G 0 with (h | h | h | h) · exact ((nonneg G) h).elim · exact Or.inl h · exact ((nonpos G) h).elim · exact Or.inr h