Context stringlengths 57 6.04k | file_name stringlengths 21 79 | start int64 14 1.49k | end int64 18 1.5k | theorem stringlengths 25 1.55k | proof stringlengths 5 7.36k | eval_complexity float64 0 1 |
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import Mathlib.Analysis.SpecificLimits.Basic
#align_import analysis.hofer from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982"
open scoped Classical
open Topology
open Filter Finset
local notation "d" => dist
#noalign pos_div_pow_pos
| Mathlib/Analysis/Hofer.lean | 33 | 104 | theorem hofer {X : Type*} [MetricSpace X] [CompleteSpace X] (x : X) (ε : ℝ) (ε_pos : 0 < ε)
{ϕ : X → ℝ} (cont : Continuous ϕ) (nonneg : ∀ y, 0 ≤ ϕ y) : ∃ ε' > 0, ∃ x' : X,
ε' ≤ ε ∧ d x' x ≤ 2 * ε ∧ ε * ϕ x ≤ ε' * ϕ x' ∧ ∀ y, d x' y ≤ ε' → ϕ y ≤ 2 * ϕ x' := by |
by_contra H
have reformulation : ∀ (x') (k : ℕ), ε * ϕ x ≤ ε / 2 ^ k * ϕ x' ↔ 2 ^ k * ϕ x ≤ ϕ x' := by
intro x' k
rw [div_mul_eq_mul_div, le_div_iff, mul_assoc, mul_le_mul_left ε_pos, mul_comm]
positivity
-- Now let's specialize to `ε/2^k`
replace H : ∀ k : ℕ, ∀ x', d x' x ≤ 2 * ε ∧ 2 ^ k * ϕ x ≤ ϕ x' →
∃ y, d x' y ≤ ε / 2 ^ k ∧ 2 * ϕ x' < ϕ y := by
intro k x'
push_neg at H
have := H (ε / 2 ^ k) (by positivity) x' (by simp [ε_pos.le, one_le_two])
simpa [reformulation] using this
clear reformulation
haveI : Nonempty X := ⟨x⟩
choose! F hF using H
-- Use the axiom of choice
-- Now define u by induction starting at x, with u_{n+1} = F(n, u_n)
let u : ℕ → X := fun n => Nat.recOn n x F
-- The properties of F translate to properties of u
have hu :
∀ n,
d (u n) x ≤ 2 * ε ∧ 2 ^ n * ϕ x ≤ ϕ (u n) →
d (u n) (u <| n + 1) ≤ ε / 2 ^ n ∧ 2 * ϕ (u n) < ϕ (u <| n + 1) := by
intro n
exact hF n (u n)
clear hF
-- Key properties of u, to be proven by induction
have key : ∀ n, d (u n) (u (n + 1)) ≤ ε / 2 ^ n ∧ 2 * ϕ (u n) < ϕ (u (n + 1)) := by
intro n
induction' n using Nat.case_strong_induction_on with n IH
· simpa [u, ε_pos.le] using hu 0
have A : d (u (n + 1)) x ≤ 2 * ε := by
rw [dist_comm]
let r := range (n + 1) -- range (n+1) = {0, ..., n}
calc
d (u 0) (u (n + 1)) ≤ ∑ i ∈ r, d (u i) (u <| i + 1) := dist_le_range_sum_dist u (n + 1)
_ ≤ ∑ i ∈ r, ε / 2 ^ i :=
(sum_le_sum fun i i_in => (IH i <| Nat.lt_succ_iff.mp <| Finset.mem_range.mp i_in).1)
_ = (∑ i ∈ r, (1 / 2 : ℝ) ^ i) * ε := by
rw [Finset.sum_mul]
congr with i
field_simp
_ ≤ 2 * ε := by gcongr; apply sum_geometric_two_le
have B : 2 ^ (n + 1) * ϕ x ≤ ϕ (u (n + 1)) := by
refine @geom_le (ϕ ∘ u) _ zero_le_two (n + 1) fun m hm => ?_
exact (IH _ <| Nat.lt_add_one_iff.1 hm).2.le
exact hu (n + 1) ⟨A, B⟩
cases' forall_and.mp key with key₁ key₂
clear hu key
-- Hence u is Cauchy
have cauchy_u : CauchySeq u := by
refine cauchySeq_of_le_geometric _ ε one_half_lt_one fun n => ?_
simpa only [one_div, inv_pow] using key₁ n
-- So u converges to some y
obtain ⟨y, limy⟩ : ∃ y, Tendsto u atTop (𝓝 y) := CompleteSpace.complete cauchy_u
-- And ϕ ∘ u goes to +∞
have lim_top : Tendsto (ϕ ∘ u) atTop atTop := by
let v n := (ϕ ∘ u) (n + 1)
suffices Tendsto v atTop atTop by rwa [tendsto_add_atTop_iff_nat] at this
have hv₀ : 0 < v 0 := by
calc
0 ≤ 2 * ϕ (u 0) := by specialize nonneg x; positivity
_ < ϕ (u (0 + 1)) := key₂ 0
apply tendsto_atTop_of_geom_le hv₀ one_lt_two
exact fun n => (key₂ (n + 1)).le
-- But ϕ ∘ u also needs to go to ϕ(y)
have lim : Tendsto (ϕ ∘ u) atTop (𝓝 (ϕ y)) := Tendsto.comp cont.continuousAt limy
-- So we have our contradiction!
exact not_tendsto_atTop_of_tendsto_nhds lim lim_top
| 0 |
import Mathlib.LinearAlgebra.BilinearForm.TensorProduct
import Mathlib.LinearAlgebra.QuadraticForm.Basic
universe uR uA uM₁ uM₂
variable {R : Type uR} {A : Type uA} {M₁ : Type uM₁} {M₂ : Type uM₂}
open TensorProduct
open LinearMap (BilinForm)
namespace QuadraticForm
section CommRing
variable [CommRing R] [CommRing A]
variable [AddCommGroup M₁] [AddCommGroup M₂]
variable [Algebra R A] [Module R M₁] [Module A M₁]
variable [SMulCommClass R A M₁] [SMulCommClass A R M₁] [IsScalarTower R A M₁]
variable [Module R M₂] [Invertible (2 : R)]
variable (R A) in
-- `noncomputable` is a performance workaround for mathlib4#7103
noncomputable def tensorDistrib :
QuadraticForm A M₁ ⊗[R] QuadraticForm R M₂ →ₗ[A] QuadraticForm A (M₁ ⊗[R] M₂) :=
letI : Invertible (2 : A) := (Invertible.map (algebraMap R A) 2).copy 2 (map_ofNat _ _).symm
-- while `letI`s would produce a better term than `let`, they would make this already-slow
-- definition even slower.
let toQ := BilinForm.toQuadraticFormLinearMap A A (M₁ ⊗[R] M₂)
let tmulB := BilinForm.tensorDistrib R A (M₁ := M₁) (M₂ := M₂)
let toB := AlgebraTensorModule.map
(QuadraticForm.associated : QuadraticForm A M₁ →ₗ[A] BilinForm A M₁)
(QuadraticForm.associated : QuadraticForm R M₂ →ₗ[R] BilinForm R M₂)
toQ ∘ₗ tmulB ∘ₗ toB
-- TODO: make the RHS `MulOpposite.op (Q₂ m₂) • Q₁ m₁` so that this has a nicer defeq for
-- `R = A` of `Q₁ m₁ * Q₂ m₂`.
@[simp]
theorem tensorDistrib_tmul (Q₁ : QuadraticForm A M₁) (Q₂ : QuadraticForm R M₂) (m₁ : M₁) (m₂ : M₂) :
tensorDistrib R A (Q₁ ⊗ₜ Q₂) (m₁ ⊗ₜ m₂) = Q₂ m₂ • Q₁ m₁ :=
letI : Invertible (2 : A) := (Invertible.map (algebraMap R A) 2).copy 2 (map_ofNat _ _).symm
(BilinForm.tensorDistrib_tmul _ _ _ _ _ _).trans <| congr_arg₂ _
(associated_eq_self_apply _ _ _) (associated_eq_self_apply _ _ _)
-- `noncomputable` is a performance workaround for mathlib4#7103
protected noncomputable abbrev tmul (Q₁ : QuadraticForm A M₁) (Q₂ : QuadraticForm R M₂) :
QuadraticForm A (M₁ ⊗[R] M₂) :=
tensorDistrib R A (Q₁ ⊗ₜ[R] Q₂)
theorem associated_tmul [Invertible (2 : A)] (Q₁ : QuadraticForm A M₁) (Q₂ : QuadraticForm R M₂) :
associated (R := A) (Q₁.tmul Q₂)
= (associated (R := A) Q₁).tmul (associated (R := R) Q₂) := by
rw [QuadraticForm.tmul, tensorDistrib, BilinForm.tmul]
dsimp
have : Subsingleton (Invertible (2 : A)) := inferInstance
convert associated_left_inverse A ((associated_isSymm A Q₁).tmul (associated_isSymm R Q₂))
theorem polarBilin_tmul [Invertible (2 : A)] (Q₁ : QuadraticForm A M₁) (Q₂ : QuadraticForm R M₂) :
polarBilin (Q₁.tmul Q₂) = ⅟(2 : A) • (polarBilin Q₁).tmul (polarBilin Q₂) := by
simp_rw [← two_nsmul_associated A, ← two_nsmul_associated R, BilinForm.tmul, tmul_smul,
← smul_tmul', map_nsmul, associated_tmul]
rw [smul_comm (_ : A) (_ : ℕ), ← smul_assoc, two_smul _ (_ : A), invOf_two_add_invOf_two,
one_smul]
variable (A) in
-- `noncomputable` is a performance workaround for mathlib4#7103
protected noncomputable def baseChange (Q : QuadraticForm R M₂) : QuadraticForm A (A ⊗[R] M₂) :=
QuadraticForm.tmul (R := R) (A := A) (M₁ := A) (M₂ := M₂) (QuadraticForm.sq (R := A)) Q
@[simp]
theorem baseChange_tmul (Q : QuadraticForm R M₂) (a : A) (m₂ : M₂) :
Q.baseChange A (a ⊗ₜ m₂) = Q m₂ • (a * a) :=
tensorDistrib_tmul _ _ _ _
theorem associated_baseChange [Invertible (2 : A)] (Q : QuadraticForm R M₂) :
associated (R := A) (Q.baseChange A) = (associated (R := R) Q).baseChange A := by
dsimp only [QuadraticForm.baseChange, LinearMap.baseChange]
rw [associated_tmul (QuadraticForm.sq (R := A)) Q, associated_sq]
exact rfl
| Mathlib/LinearAlgebra/QuadraticForm/TensorProduct.lean | 101 | 105 | theorem polarBilin_baseChange [Invertible (2 : A)] (Q : QuadraticForm R M₂) :
polarBilin (Q.baseChange A) = (polarBilin Q).baseChange A := by |
rw [QuadraticForm.baseChange, BilinForm.baseChange, polarBilin_tmul, BilinForm.tmul,
← LinearMap.map_smul, smul_tmul', ← two_nsmul_associated R, coe_associatedHom, associated_sq,
smul_comm, ← smul_assoc, two_smul, invOf_two_add_invOf_two, one_smul]
| 0 |
import Mathlib.Analysis.Normed.Group.InfiniteSum
import Mathlib.Topology.Instances.ENNReal
#align_import analysis.calculus.series from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982"
open Set Metric TopologicalSpace Function Filter
open scoped Topology NNReal
variable {α β F : Type*} [NormedAddCommGroup F] [CompleteSpace F] {u : α → ℝ}
| Mathlib/Analysis/NormedSpace/FunctionSeries.lean | 28 | 39 | theorem tendstoUniformlyOn_tsum {f : α → β → F} (hu : Summable u) {s : Set β}
(hfu : ∀ n x, x ∈ s → ‖f n x‖ ≤ u n) :
TendstoUniformlyOn (fun t : Finset α => fun x => ∑ n ∈ t, f n x) (fun x => ∑' n, f n x) atTop
s := by |
refine tendstoUniformlyOn_iff.2 fun ε εpos => ?_
filter_upwards [(tendsto_order.1 (tendsto_tsum_compl_atTop_zero u)).2 _ εpos] with t ht x hx
have A : Summable fun n => ‖f n x‖ :=
.of_nonneg_of_le (fun _ ↦ norm_nonneg _) (fun n => hfu n x hx) hu
rw [dist_eq_norm, ← sum_add_tsum_subtype_compl A.of_norm t, add_sub_cancel_left]
apply lt_of_le_of_lt _ ht
apply (norm_tsum_le_tsum_norm (A.subtype _)).trans
exact tsum_le_tsum (fun n => hfu _ _ hx) (A.subtype _) (hu.subtype _)
| 0 |
import Mathlib.Analysis.Complex.Liouville
import Mathlib.Analysis.Calculus.Deriv.Polynomial
import Mathlib.FieldTheory.PolynomialGaloisGroup
import Mathlib.Topology.Algebra.Polynomial
#align_import analysis.complex.polynomial from "leanprover-community/mathlib"@"17ef379e997badd73e5eabb4d38f11919ab3c4b3"
open Polynomial Bornology Complex
open scoped ComplexConjugate
namespace Complex
| Mathlib/Analysis/Complex/Polynomial.lean | 34 | 45 | theorem exists_root {f : ℂ[X]} (hf : 0 < degree f) : ∃ z : ℂ, IsRoot f z := by |
by_contra! hf'
/- Since `f` has no roots, `f⁻¹` is differentiable. And since `f` is a polynomial, it tends to
infinity at infinity, thus `f⁻¹` tends to zero at infinity. By Liouville's theorem, `f⁻¹ = 0`. -/
have (z : ℂ) : (f.eval z)⁻¹ = 0 :=
(f.differentiable.inv hf').apply_eq_of_tendsto_cocompact z <|
Metric.cobounded_eq_cocompact (α := ℂ) ▸ (Filter.tendsto_inv₀_cobounded.comp <| by
simpa only [tendsto_norm_atTop_iff_cobounded]
using f.tendsto_norm_atTop hf tendsto_norm_cobounded_atTop)
-- Thus `f = 0`, contradicting the fact that `0 < degree f`.
obtain rfl : f = C 0 := Polynomial.funext fun z ↦ inv_injective <| by simp [this]
simp at hf
| 0 |
import Mathlib.Data.Nat.Squarefree
import Mathlib.NumberTheory.Zsqrtd.QuadraticReciprocity
import Mathlib.Tactic.LinearCombination
#align_import number_theory.sum_two_squares from "leanprover-community/mathlib"@"5b2fe80501ff327b9109fb09b7cc8c325cd0d7d9"
section NegOneSquare
-- This could be formulated for a general integer `a` in place of `-1`,
-- but it would not directly specialize to `-1`,
-- because `((-1 : ℤ) : ZMod n)` is not the same as `(-1 : ZMod n)`.
| Mathlib/NumberTheory/SumTwoSquares.lean | 77 | 81 | theorem ZMod.isSquare_neg_one_of_dvd {m n : ℕ} (hd : m ∣ n) (hs : IsSquare (-1 : ZMod n)) :
IsSquare (-1 : ZMod m) := by |
let f : ZMod n →+* ZMod m := ZMod.castHom hd _
rw [← RingHom.map_one f, ← RingHom.map_neg]
exact hs.map f
| 0 |
import Mathlib.MeasureTheory.Measure.Lebesgue.Basic
import Mathlib.NumberTheory.Liouville.Residual
import Mathlib.NumberTheory.Liouville.LiouvilleWith
import Mathlib.Analysis.PSeries
#align_import number_theory.liouville.measure from "leanprover-community/mathlib"@"fd5edc43dc4f10b85abfe544b88f82cf13c5f844"
open scoped Filter ENNReal Topology NNReal
open Filter Set Metric MeasureTheory Real
| Mathlib/NumberTheory/Liouville/Measure.lean | 34 | 71 | theorem setOf_liouvilleWith_subset_aux :
{ x : ℝ | ∃ p > 2, LiouvilleWith p x } ⊆
⋃ m : ℤ, (· + (m : ℝ)) ⁻¹' ⋃ n > (0 : ℕ),
{ x : ℝ | ∃ᶠ b : ℕ in atTop, ∃ a ∈ Finset.Icc (0 : ℤ) b,
|x - (a : ℤ) / b| < 1 / (b : ℝ) ^ (2 + 1 / n : ℝ) } := by |
rintro x ⟨p, hp, hxp⟩
rcases exists_nat_one_div_lt (sub_pos.2 hp) with ⟨n, hn⟩
rw [lt_sub_iff_add_lt'] at hn
suffices ∀ y : ℝ, LiouvilleWith p y → y ∈ Ico (0 : ℝ) 1 → ∃ᶠ b : ℕ in atTop,
∃ a ∈ Finset.Icc (0 : ℤ) b, |y - a / b| < 1 / (b : ℝ) ^ (2 + 1 / (n + 1 : ℕ) : ℝ) by
simp only [mem_iUnion, mem_preimage]
have hx : x + ↑(-⌊x⌋) ∈ Ico (0 : ℝ) 1 := by
simp only [Int.floor_le, Int.lt_floor_add_one, add_neg_lt_iff_le_add', zero_add, and_self_iff,
mem_Ico, Int.cast_neg, le_add_neg_iff_add_le]
exact ⟨-⌊x⌋, n + 1, n.succ_pos, this _ (hxp.add_int _) hx⟩
clear hxp x; intro x hxp hx01
refine ((hxp.frequently_lt_rpow_neg hn).and_eventually (eventually_ge_atTop 1)).mono ?_
rintro b ⟨⟨a, -, hlt⟩, hb⟩
rw [rpow_neg b.cast_nonneg, ← one_div, ← Nat.cast_succ] at hlt
refine ⟨a, ?_, hlt⟩
replace hb : (1 : ℝ) ≤ b := Nat.one_le_cast.2 hb
have hb0 : (0 : ℝ) < b := zero_lt_one.trans_le hb
replace hlt : |x - a / b| < 1 / b := by
refine hlt.trans_le (one_div_le_one_div_of_le hb0 ?_)
calc
(b : ℝ) = (b : ℝ) ^ (1 : ℝ) := (rpow_one _).symm
_ ≤ (b : ℝ) ^ (2 + 1 / (n + 1 : ℕ) : ℝ) :=
rpow_le_rpow_of_exponent_le hb (one_le_two.trans ?_)
simpa using n.cast_add_one_pos.le
rw [sub_div' _ _ _ hb0.ne', abs_div, abs_of_pos hb0, div_lt_div_right hb0, abs_sub_lt_iff,
sub_lt_iff_lt_add, sub_lt_iff_lt_add, ← sub_lt_iff_lt_add'] at hlt
rw [Finset.mem_Icc, ← Int.lt_add_one_iff, ← Int.lt_add_one_iff, ← neg_lt_iff_pos_add, add_comm, ←
@Int.cast_lt ℝ, ← @Int.cast_lt ℝ]
push_cast
refine ⟨lt_of_le_of_lt ?_ hlt.1, hlt.2.trans_le ?_⟩
· simp only [mul_nonneg hx01.left b.cast_nonneg, neg_le_sub_iff_le_add, le_add_iff_nonneg_left]
· rw [add_le_add_iff_left]
exact mul_le_of_le_one_left hb0.le hx01.2.le
| 0 |
import Mathlib.RingTheory.Adjoin.FG
#align_import ring_theory.adjoin.tower from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a"
open Pointwise
universe u v w u₁
variable (R : Type u) (S : Type v) (A : Type w) (B : Type u₁)
namespace Algebra
| Mathlib/RingTheory/Adjoin/Tower.lean | 30 | 46 | theorem adjoin_restrictScalars (C D E : Type*) [CommSemiring C] [CommSemiring D] [CommSemiring E]
[Algebra C D] [Algebra C E] [Algebra D E] [IsScalarTower C D E] (S : Set E) :
(Algebra.adjoin D S).restrictScalars C =
(Algebra.adjoin ((⊤ : Subalgebra C D).map (IsScalarTower.toAlgHom C D E)) S).restrictScalars
C := by |
suffices
Set.range (algebraMap D E) =
Set.range (algebraMap ((⊤ : Subalgebra C D).map (IsScalarTower.toAlgHom C D E)) E) by
ext x
change x ∈ Subsemiring.closure (_ ∪ S) ↔ x ∈ Subsemiring.closure (_ ∪ S)
rw [this]
ext x
constructor
· rintro ⟨y, hy⟩
exact ⟨⟨algebraMap D E y, ⟨y, ⟨Algebra.mem_top, rfl⟩⟩⟩, hy⟩
· rintro ⟨⟨y, ⟨z, ⟨h0, h1⟩⟩⟩, h2⟩
exact ⟨z, Eq.trans h1 h2⟩
| 0 |
import Mathlib.Algebra.BigOperators.NatAntidiagonal
import Mathlib.Algebra.Order.Ring.Abs
import Mathlib.Data.Nat.Choose.Sum
import Mathlib.RingTheory.PowerSeries.Basic
#align_import ring_theory.power_series.well_known from "leanprover-community/mathlib"@"8199f6717c150a7fe91c4534175f4cf99725978f"
namespace PowerSeries
section invOneSubPow
variable {S : Type*} [CommRing S] (d : ℕ)
| Mathlib/RingTheory/PowerSeries/WellKnown.lean | 84 | 89 | theorem mk_one_mul_one_sub_eq_one : (mk 1 : S⟦X⟧) * (1 - X) = 1 := by |
rw [mul_comm, ext_iff]
intro n
cases n with
| zero => simp
| succ n => simp [sub_mul]
| 0 |
import Mathlib.Analysis.NormedSpace.Star.GelfandDuality
import Mathlib.Topology.Algebra.StarSubalgebra
#align_import analysis.normed_space.star.continuous_functional_calculus from "leanprover-community/mathlib"@"31c24aa72e7b3e5ed97a8412470e904f82b81004"
open scoped Pointwise ENNReal NNReal ComplexOrder
open WeakDual WeakDual.CharacterSpace elementalStarAlgebra
variable {A : Type*} [NormedRing A] [NormedAlgebra ℂ A]
variable [StarRing A] [CstarRing A] [StarModule ℂ A]
instance {R A : Type*} [CommRing R] [StarRing R] [NormedRing A] [Algebra R A] [StarRing A]
[ContinuousStar A] [StarModule R A] (a : A) [IsStarNormal a] :
NormedCommRing (elementalStarAlgebra R a) :=
{ SubringClass.toNormedRing (elementalStarAlgebra R a) with
mul_comm := mul_comm }
-- Porting note: these hack instances no longer seem to be necessary
#noalign elemental_star_algebra.complex.normed_algebra
variable [CompleteSpace A] (a : A) [IsStarNormal a] (S : StarSubalgebra ℂ A)
theorem spectrum_star_mul_self_of_isStarNormal :
spectrum ℂ (star a * a) ⊆ Set.Icc (0 : ℂ) ‖star a * a‖ := by
-- this instance should be found automatically, but without providing it Lean goes on a wild
-- goose chase when trying to apply `spectrum.gelfandTransform_eq`.
--letI := elementalStarAlgebra.Complex.normedAlgebra a
rcases subsingleton_or_nontrivial A with ⟨⟩
· simp only [spectrum.of_subsingleton, Set.empty_subset]
· set a' : elementalStarAlgebra ℂ a := ⟨a, self_mem ℂ a⟩
refine (spectrum.subset_starSubalgebra (star a' * a')).trans ?_
rw [← spectrum.gelfandTransform_eq (star a' * a'), ContinuousMap.spectrum_eq_range]
rintro - ⟨φ, rfl⟩
rw [gelfandTransform_apply_apply ℂ _ (star a' * a') φ, map_mul φ, map_star φ]
rw [Complex.eq_coe_norm_of_nonneg (star_mul_self_nonneg _), ← map_star, ← map_mul]
exact ⟨by positivity, Complex.real_le_real.2 (AlgHom.norm_apply_le_self φ (star a' * a'))⟩
#align spectrum_star_mul_self_of_is_star_normal spectrum_star_mul_self_of_isStarNormal
variable {a}
| Mathlib/Analysis/NormedSpace/Star/ContinuousFunctionalCalculus.lean | 103 | 174 | theorem elementalStarAlgebra.isUnit_of_isUnit_of_isStarNormal (h : IsUnit a) :
IsUnit (⟨a, self_mem ℂ a⟩ : elementalStarAlgebra ℂ a) := by |
/- Sketch of proof: Because `a` is normal, it suffices to prove that `star a * a` is invertible
in `elementalStarAlgebra ℂ a`. For this it suffices to prove that it is sufficiently close to a
unit, namely `algebraMap ℂ _ ‖star a * a‖`, and in this case the required distance is
`‖star a * a‖`. So one must show `‖star a * a - algebraMap ℂ _ ‖star a * a‖‖ < ‖star a * a‖`.
Since `star a * a - algebraMap ℂ _ ‖star a * a‖` is selfadjoint, by a corollary of Gelfand's
formula for the spectral radius (`IsSelfAdjoint.spectralRadius_eq_nnnorm`) its norm is the
supremum of the norms of elements in its spectrum (we may use the spectrum in `A` here because
the norm in `A` and the norm in the subalgebra coincide).
By `spectrum_star_mul_self_of_isStarNormal`, the spectrum (in the algebra `A`) of `star a * a`
is contained in the interval `[0, ‖star a * a‖]`, and since `a` (and hence `star a * a`) is
invertible in `A`, we may omit `0` from this interval. Therefore, by basic spectral mapping
properties, the spectrum (in the algebra `A`) of `star a * a - algebraMap ℂ _ ‖star a * a‖` is
contained in `[0, ‖star a * a‖)`. The supremum of the (norms of) elements of the spectrum must
be *strictly* less that `‖star a * a‖` because the spectrum is compact, which completes the
proof. -/
/- We may assume `A` is nontrivial. It suffices to show that `star a * a` is invertible in the
commutative (because `a` is normal) ring `elementalStarAlgebra ℂ a`. Indeed, by commutativity,
if `star a * a` is invertible, then so is `a`. -/
nontriviality A
set a' : elementalStarAlgebra ℂ a := ⟨a, self_mem ℂ a⟩
suffices IsUnit (star a' * a') from (IsUnit.mul_iff.1 this).2
replace h := (show Commute (star a) a from star_comm_self' a).isUnit_mul_iff.2 ⟨h.star, h⟩
/- Since `a` is invertible, `‖star a * a‖ ≠ 0`, so `‖star a * a‖ • 1` is invertible in
`elementalStarAlgebra ℂ a`, and so it suffices to show that the distance between this unit and
`star a * a` is less than `‖star a * a‖`. -/
have h₁ : (‖star a * a‖ : ℂ) ≠ 0 := Complex.ofReal_ne_zero.mpr (norm_ne_zero_iff.mpr h.ne_zero)
set u : Units (elementalStarAlgebra ℂ a) :=
Units.map (algebraMap ℂ (elementalStarAlgebra ℂ a)).toMonoidHom (Units.mk0 _ h₁)
refine ⟨u.ofNearby _ ?_, rfl⟩
simp only [u, Units.coe_map, Units.val_inv_eq_inv_val, RingHom.toMonoidHom_eq_coe, Units.val_mk0,
Units.coe_map_inv, MonoidHom.coe_coe, norm_algebraMap', norm_inv, Complex.norm_eq_abs,
Complex.abs_ofReal, abs_norm, inv_inv]
--RingHom.coe_monoidHom,
-- Complex.abs_ofReal, map_inv₀,
--rw [norm_algebraMap', inv_inv, Complex.norm_eq_abs, abs_norm]I-
/- Since `a` is invertible, by `spectrum_star_mul_self_of_isStarNormal`, the spectrum (in `A`)
of `star a * a` is contained in the half-open interval `(0, ‖star a * a‖]`. Therefore, by basic
spectral mapping properties, the spectrum of `‖star a * a‖ • 1 - star a * a` is contained in
`[0, ‖star a * a‖)`. -/
have h₂ : ∀ z ∈ spectrum ℂ (algebraMap ℂ A ‖star a * a‖ - star a * a), ‖z‖₊ < ‖star a * a‖₊ := by
intro z hz
rw [← spectrum.singleton_sub_eq, Set.singleton_sub] at hz
have h₃ : z ∈ Set.Icc (0 : ℂ) ‖star a * a‖ := by
replace hz := Set.image_subset _ (spectrum_star_mul_self_of_isStarNormal a) hz
rwa [Set.image_const_sub_Icc, sub_self, sub_zero] at hz
refine lt_of_le_of_ne (Complex.real_le_real.1 <| Complex.eq_coe_norm_of_nonneg h₃.1 ▸ h₃.2) ?_
· intro hz'
replace hz' := congr_arg (fun x : ℝ≥0 => ((x : ℝ) : ℂ)) hz'
simp only [coe_nnnorm] at hz'
rw [← Complex.eq_coe_norm_of_nonneg h₃.1] at hz'
obtain ⟨w, hw₁, hw₂⟩ := hz
refine (spectrum.zero_not_mem_iff ℂ).mpr h ?_
rw [hz', sub_eq_self] at hw₂
rwa [hw₂] at hw₁
/- The norm of `‖star a * a‖ • 1 - star a * a` in the subalgebra and in `A` coincide. In `A`,
because this element is selfadjoint, by `IsSelfAdjoint.spectralRadius_eq_nnnorm`, its norm is
the supremum of the norms of the elements of the spectrum, which is strictly less than
`‖star a * a‖` by `h₂` and because the spectrum is compact. -/
exact ENNReal.coe_lt_coe.1
(calc
(‖star a' * a' - algebraMap ℂ _ ‖star a * a‖‖₊ : ℝ≥0∞) =
‖algebraMap ℂ A ‖star a * a‖ - star a * a‖₊ := by
rw [← nnnorm_neg, neg_sub]; rfl
_ = spectralRadius ℂ (algebraMap ℂ A ‖star a * a‖ - star a * a) := by
refine (IsSelfAdjoint.spectralRadius_eq_nnnorm ?_).symm
rw [IsSelfAdjoint, star_sub, star_mul, star_star, ← algebraMap_star_comm]
congr!
exact RCLike.conj_ofReal _
_ < ‖star a * a‖₊ := spectrum.spectralRadius_lt_of_forall_lt _ h₂)
| 0 |
import Mathlib.Algebra.Algebra.Tower
import Mathlib.Algebra.GroupWithZero.NonZeroDivisors
import Mathlib.GroupTheory.MonoidLocalization
import Mathlib.RingTheory.Ideal.Basic
import Mathlib.GroupTheory.GroupAction.Ring
#align_import ring_theory.localization.basic from "leanprover-community/mathlib"@"b69c9a770ecf37eb21f7b8cf4fa00de3b62694ec"
open Function
section CommSemiring
variable {R : Type*} [CommSemiring R] (M : Submonoid R) (S : Type*) [CommSemiring S]
variable [Algebra R S] {P : Type*} [CommSemiring P]
@[mk_iff] class IsLocalization : Prop where
-- Porting note: add ' to fields, and made new versions of these with either `S` or `M` explicit.
map_units' : ∀ y : M, IsUnit (algebraMap R S y)
surj' : ∀ z : S, ∃ x : R × M, z * algebraMap R S x.2 = algebraMap R S x.1
exists_of_eq : ∀ {x y}, algebraMap R S x = algebraMap R S y → ∃ c : M, ↑c * x = ↑c * y
#align is_localization IsLocalization
variable {M}
namespace IsLocalization
section IsLocalization
variable [IsLocalization M S]
section
@[inherit_doc IsLocalization.map_units']
theorem map_units : ∀ y : M, IsUnit (algebraMap R S y) :=
IsLocalization.map_units'
variable (M) {S}
@[inherit_doc IsLocalization.surj']
theorem surj : ∀ z : S, ∃ x : R × M, z * algebraMap R S x.2 = algebraMap R S x.1 :=
IsLocalization.surj'
variable (S)
@[inherit_doc IsLocalization.exists_of_eq]
theorem eq_iff_exists {x y} : algebraMap R S x = algebraMap R S y ↔ ∃ c : M, ↑c * x = ↑c * y :=
Iff.intro IsLocalization.exists_of_eq fun ⟨c, h⟩ ↦ by
apply_fun algebraMap R S at h
rw [map_mul, map_mul] at h
exact (IsLocalization.map_units S c).mul_right_inj.mp h
variable {S}
theorem of_le (N : Submonoid R) (h₁ : M ≤ N) (h₂ : ∀ r ∈ N, IsUnit (algebraMap R S r)) :
IsLocalization N S where
map_units' r := h₂ r r.2
surj' s :=
have ⟨⟨x, y, hy⟩, H⟩ := IsLocalization.surj M s
⟨⟨x, y, h₁ hy⟩, H⟩
exists_of_eq {x y} := by
rw [IsLocalization.eq_iff_exists M]
rintro ⟨c, hc⟩
exact ⟨⟨c, h₁ c.2⟩, hc⟩
#align is_localization.of_le IsLocalization.of_le
variable (S)
@[simps]
def toLocalizationWithZeroMap : Submonoid.LocalizationWithZeroMap M S where
__ := algebraMap R S
toFun := algebraMap R S
map_units' := IsLocalization.map_units _
surj' := IsLocalization.surj _
exists_of_eq _ _ := IsLocalization.exists_of_eq
#align is_localization.to_localization_with_zero_map IsLocalization.toLocalizationWithZeroMap
abbrev toLocalizationMap : Submonoid.LocalizationMap M S :=
(toLocalizationWithZeroMap M S).toLocalizationMap
#align is_localization.to_localization_map IsLocalization.toLocalizationMap
@[simp]
theorem toLocalizationMap_toMap : (toLocalizationMap M S).toMap = (algebraMap R S : R →*₀ S) :=
rfl
#align is_localization.to_localization_map_to_map IsLocalization.toLocalizationMap_toMap
theorem toLocalizationMap_toMap_apply (x) : (toLocalizationMap M S).toMap x = algebraMap R S x :=
rfl
#align is_localization.to_localization_map_to_map_apply IsLocalization.toLocalizationMap_toMap_apply
theorem surj₂ : ∀ z w : S, ∃ z' w' : R, ∃ d : M,
(z * algebraMap R S d = algebraMap R S z') ∧ (w * algebraMap R S d = algebraMap R S w') :=
(toLocalizationMap M S).surj₂
end
variable (M) {S}
noncomputable def sec (z : S) : R × M :=
Classical.choose <| IsLocalization.surj _ z
#align is_localization.sec IsLocalization.sec
@[simp]
theorem toLocalizationMap_sec : (toLocalizationMap M S).sec = sec M :=
rfl
#align is_localization.to_localization_map_sec IsLocalization.toLocalizationMap_sec
theorem sec_spec (z : S) :
z * algebraMap R S (IsLocalization.sec M z).2 = algebraMap R S (IsLocalization.sec M z).1 :=
Classical.choose_spec <| IsLocalization.surj _ z
#align is_localization.sec_spec IsLocalization.sec_spec
theorem sec_spec' (z : S) :
algebraMap R S (IsLocalization.sec M z).1 = algebraMap R S (IsLocalization.sec M z).2 * z := by
rw [mul_comm, sec_spec]
#align is_localization.sec_spec' IsLocalization.sec_spec'
variable {M}
theorem subsingleton (h : 0 ∈ M) : Subsingleton S := (toLocalizationMap M S).subsingleton h
theorem map_right_cancel {x y} {c : M} (h : algebraMap R S (c * x) = algebraMap R S (c * y)) :
algebraMap R S x = algebraMap R S y :=
(toLocalizationMap M S).map_right_cancel h
#align is_localization.map_right_cancel IsLocalization.map_right_cancel
theorem map_left_cancel {x y} {c : M} (h : algebraMap R S (x * c) = algebraMap R S (y * c)) :
algebraMap R S x = algebraMap R S y :=
(toLocalizationMap M S).map_left_cancel h
#align is_localization.map_left_cancel IsLocalization.map_left_cancel
| Mathlib/RingTheory/Localization/Basic.lean | 222 | 225 | theorem eq_zero_of_fst_eq_zero {z x} {y : M} (h : z * algebraMap R S y = algebraMap R S x)
(hx : x = 0) : z = 0 := by |
rw [hx, (algebraMap R S).map_zero] at h
exact (IsUnit.mul_left_eq_zero (IsLocalization.map_units S y)).1 h
| 0 |
import Mathlib.MeasureTheory.Integral.IntervalIntegral
import Mathlib.MeasureTheory.Integral.Average
#align_import measure_theory.integral.interval_average from "leanprover-community/mathlib"@"9003f28797c0664a49e4179487267c494477d853"
open MeasureTheory Set TopologicalSpace
open scoped Interval
variable {E : Type*} [NormedAddCommGroup E] [NormedSpace ℝ E] [CompleteSpace E]
notation3 "⨍ "(...)" in "a".."b",
"r:60:(scoped f => average (Measure.restrict volume (uIoc a b)) f) => r
theorem interval_average_symm (f : ℝ → E) (a b : ℝ) : (⨍ x in a..b, f x) = ⨍ x in b..a, f x := by
rw [setAverage_eq, setAverage_eq, uIoc_comm]
#align interval_average_symm interval_average_symm
| Mathlib/MeasureTheory/Integral/IntervalAverage.lean | 43 | 49 | theorem interval_average_eq (f : ℝ → E) (a b : ℝ) :
(⨍ x in a..b, f x) = (b - a)⁻¹ • ∫ x in a..b, f x := by |
rcases le_or_lt a b with h | h
· rw [setAverage_eq, uIoc_of_le h, Real.volume_Ioc, intervalIntegral.integral_of_le h,
ENNReal.toReal_ofReal (sub_nonneg.2 h)]
· rw [setAverage_eq, uIoc_of_lt h, Real.volume_Ioc, intervalIntegral.integral_of_ge h.le,
ENNReal.toReal_ofReal (sub_nonneg.2 h.le), smul_neg, ← neg_smul, ← inv_neg, neg_sub]
| 0 |
import Mathlib.CategoryTheory.Sites.Spaces
import Mathlib.Topology.Sheaves.Sheaf
import Mathlib.CategoryTheory.Sites.DenseSubsite
#align_import topology.sheaves.sheaf_condition.sites from "leanprover-community/mathlib"@"d39590fc8728fbf6743249802486f8c91ffe07bc"
noncomputable section
set_option linter.uppercaseLean3 false -- Porting note: Added because of too many false positives
universe w v u
open CategoryTheory TopologicalSpace
namespace TopCat.Presheaf
variable {X : TopCat.{w}}
def coveringOfPresieve (U : Opens X) (R : Presieve U) : (ΣV, { f : V ⟶ U // R f }) → Opens X :=
fun f => f.1
#align Top.presheaf.covering_of_presieve TopCat.Presheaf.coveringOfPresieve
@[simp]
theorem coveringOfPresieve_apply (U : Opens X) (R : Presieve U) (f : ΣV, { f : V ⟶ U // R f }) :
coveringOfPresieve U R f = f.1 := rfl
#align Top.presheaf.covering_of_presieve_apply TopCat.Presheaf.coveringOfPresieve_apply
def presieveOfCoveringAux {ι : Type v} (U : ι → Opens X) (Y : Opens X) : Presieve Y :=
fun V _ => ∃ i, V = U i
#align Top.presheaf.presieve_of_covering_aux TopCat.Presheaf.presieveOfCoveringAux
def presieveOfCovering {ι : Type v} (U : ι → Opens X) : Presieve (iSup U) :=
presieveOfCoveringAux U (iSup U)
#align Top.presheaf.presieve_of_covering TopCat.Presheaf.presieveOfCovering
@[simp]
| Mathlib/Topology/Sheaves/SheafCondition/Sites.lean | 90 | 94 | theorem covering_presieve_eq_self {Y : Opens X} (R : Presieve Y) :
presieveOfCoveringAux (coveringOfPresieve Y R) Y = R := by |
funext Z
ext f
exact ⟨fun ⟨⟨_, f', h⟩, rfl⟩ => by rwa [Subsingleton.elim f f'], fun h => ⟨⟨Z, f, h⟩, rfl⟩⟩
| 0 |
import Mathlib.RingTheory.Localization.AtPrime
import Mathlib.RingTheory.Localization.Basic
import Mathlib.RingTheory.Localization.FractionRing
#align_import ring_theory.localization.localization_localization from "leanprover-community/mathlib"@"831c494092374cfe9f50591ed0ac81a25efc5b86"
open Function
namespace IsLocalization
section LocalizationLocalization
variable {R : Type*} [CommSemiring R] (M : Submonoid R) {S : Type*} [CommSemiring S]
variable [Algebra R S] {P : Type*} [CommSemiring P]
variable (N : Submonoid S) (T : Type*) [CommSemiring T] [Algebra R T]
section
variable [Algebra S T] [IsScalarTower R S T]
-- This should only be defined when `S` is the localization `M⁻¹R`, hence the nolint.
@[nolint unusedArguments]
def localizationLocalizationSubmodule : Submonoid R :=
(N ⊔ M.map (algebraMap R S)).comap (algebraMap R S)
#align is_localization.localization_localization_submodule IsLocalization.localizationLocalizationSubmodule
variable {M N}
@[simp]
| Mathlib/RingTheory/Localization/LocalizationLocalization.lean | 53 | 61 | theorem mem_localizationLocalizationSubmodule {x : R} :
x ∈ localizationLocalizationSubmodule M N ↔
∃ (y : N) (z : M), algebraMap R S x = y * algebraMap R S z := by |
rw [localizationLocalizationSubmodule, Submonoid.mem_comap, Submonoid.mem_sup]
constructor
· rintro ⟨y, hy, _, ⟨z, hz, rfl⟩, e⟩
exact ⟨⟨y, hy⟩, ⟨z, hz⟩, e.symm⟩
· rintro ⟨y, z, e⟩
exact ⟨y, y.prop, _, ⟨z, z.prop, rfl⟩, e.symm⟩
| 0 |
import Mathlib.MeasureTheory.Measure.Doubling
import Mathlib.MeasureTheory.Covering.Vitali
import Mathlib.MeasureTheory.Covering.Differentiation
#align_import measure_theory.covering.density_theorem from "leanprover-community/mathlib"@"5f6e827d81dfbeb6151d7016586ceeb0099b9655"
noncomputable section
open Set Filter Metric MeasureTheory TopologicalSpace
open scoped NNReal Topology
namespace IsUnifLocDoublingMeasure
variable {α : Type*} [MetricSpace α] [MeasurableSpace α] (μ : Measure α)
[IsUnifLocDoublingMeasure μ]
section
variable [SecondCountableTopology α] [BorelSpace α] [IsLocallyFiniteMeasure μ]
open scoped Topology
irreducible_def vitaliFamily (K : ℝ) : VitaliFamily μ := by
let R := scalingScaleOf μ (max (4 * K + 3) 3)
have Rpos : 0 < R := scalingScaleOf_pos _ _
have A : ∀ x : α, ∃ᶠ r in 𝓝[>] (0 : ℝ),
μ (closedBall x (3 * r)) ≤ scalingConstantOf μ (max (4 * K + 3) 3) * μ (closedBall x r) := by
intro x
apply frequently_iff.2 fun {U} hU => ?_
obtain ⟨ε, εpos, hε⟩ := mem_nhdsWithin_Ioi_iff_exists_Ioc_subset.1 hU
refine ⟨min ε R, hε ⟨lt_min εpos Rpos, min_le_left _ _⟩, ?_⟩
exact measure_mul_le_scalingConstantOf_mul μ
⟨zero_lt_three, le_max_right _ _⟩ (min_le_right _ _)
exact (Vitali.vitaliFamily μ (scalingConstantOf μ (max (4 * K + 3) 3)) A).enlarge (R / 4)
(by linarith)
#align is_unif_loc_doubling_measure.vitali_family IsUnifLocDoublingMeasure.vitaliFamily
| Mathlib/MeasureTheory/Covering/DensityTheorem.lean | 71 | 109 | theorem closedBall_mem_vitaliFamily_of_dist_le_mul {K : ℝ} {x y : α} {r : ℝ} (h : dist x y ≤ K * r)
(rpos : 0 < r) : closedBall y r ∈ (vitaliFamily μ K).setsAt x := by |
let R := scalingScaleOf μ (max (4 * K + 3) 3)
simp only [vitaliFamily, VitaliFamily.enlarge, Vitali.vitaliFamily, mem_union, mem_setOf_eq,
isClosed_ball, true_and_iff, (nonempty_ball.2 rpos).mono ball_subset_interior_closedBall,
measurableSet_closedBall]
/- The measure is doubling on scales smaller than `R`. Therefore, we treat differently small
and large balls. For large balls, this follows directly from the enlargement we used in the
definition. -/
by_cases H : closedBall y r ⊆ closedBall x (R / 4)
swap; · exact Or.inr H
left
/- For small balls, there is the difficulty that `r` could be large but still the ball could be
small, if the annulus `{y | ε ≤ dist y x ≤ R/4}` is empty. We split between the cases `r ≤ R`
and `r > R`, and use the doubling for the former and rough estimates for the latter. -/
rcases le_or_lt r R with (hr | hr)
· refine ⟨(K + 1) * r, ?_⟩
constructor
· apply closedBall_subset_closedBall'
rw [dist_comm]
linarith
· have I1 : closedBall x (3 * ((K + 1) * r)) ⊆ closedBall y ((4 * K + 3) * r) := by
apply closedBall_subset_closedBall'
linarith
have I2 : closedBall y ((4 * K + 3) * r) ⊆ closedBall y (max (4 * K + 3) 3 * r) := by
apply closedBall_subset_closedBall
exact mul_le_mul_of_nonneg_right (le_max_left _ _) rpos.le
apply (measure_mono (I1.trans I2)).trans
exact measure_mul_le_scalingConstantOf_mul _
⟨zero_lt_three.trans_le (le_max_right _ _), le_rfl⟩ hr
· refine ⟨R / 4, H, ?_⟩
have : closedBall x (3 * (R / 4)) ⊆ closedBall y r := by
apply closedBall_subset_closedBall'
have A : y ∈ closedBall y r := mem_closedBall_self rpos.le
have B := mem_closedBall'.1 (H A)
linarith
apply (measure_mono this).trans _
refine le_mul_of_one_le_left (zero_le _) ?_
exact ENNReal.one_le_coe_iff.2 (le_max_right _ _)
| 0 |
import Mathlib.LinearAlgebra.Projectivization.Basic
#align_import linear_algebra.projective_space.independence from "leanprover-community/mathlib"@"1e82f5ec4645f6a92bb9e02fce51e44e3bc3e1fe"
open scoped LinearAlgebra.Projectivization
variable {ι K V : Type*} [DivisionRing K] [AddCommGroup V] [Module K V] {f : ι → ℙ K V}
namespace Projectivization
inductive Independent : (ι → ℙ K V) → Prop
| mk (f : ι → V) (hf : ∀ i : ι, f i ≠ 0) (hl : LinearIndependent K f) :
Independent fun i => mk K (f i) (hf i)
#align projectivization.independent Projectivization.Independent
theorem independent_iff : Independent f ↔ LinearIndependent K (Projectivization.rep ∘ f) := by
refine ⟨?_, fun h => ?_⟩
· rintro ⟨ff, hff, hh⟩
choose a ha using fun i : ι => exists_smul_eq_mk_rep K (ff i) (hff i)
convert hh.units_smul a
ext i
exact (ha i).symm
· convert Independent.mk _ _ h
· simp only [mk_rep, Function.comp_apply]
· intro i
apply rep_nonzero
#align projectivization.independent_iff Projectivization.independent_iff
theorem independent_iff_completeLattice_independent :
Independent f ↔ CompleteLattice.Independent fun i => (f i).submodule := by
refine ⟨?_, fun h => ?_⟩
· rintro ⟨f, hf, hi⟩
simp only [submodule_mk]
exact (CompleteLattice.independent_iff_linearIndependent_of_ne_zero (R := K) hf).mpr hi
· rw [independent_iff]
refine h.linearIndependent (Projectivization.submodule ∘ f) (fun i => ?_) fun i => ?_
· simpa only [Function.comp_apply, submodule_eq] using Submodule.mem_span_singleton_self _
· exact rep_nonzero (f i)
#align projectivization.independent_iff_complete_lattice_independent Projectivization.independent_iff_completeLattice_independent
inductive Dependent : (ι → ℙ K V) → Prop
| mk (f : ι → V) (hf : ∀ i : ι, f i ≠ 0) (h : ¬LinearIndependent K f) :
Dependent fun i => mk K (f i) (hf i)
#align projectivization.dependent Projectivization.Dependent
| Mathlib/LinearAlgebra/Projectivization/Independence.lean | 84 | 94 | theorem dependent_iff : Dependent f ↔ ¬LinearIndependent K (Projectivization.rep ∘ f) := by |
refine ⟨?_, fun h => ?_⟩
· rintro ⟨ff, hff, hh1⟩
contrapose! hh1
choose a ha using fun i : ι => exists_smul_eq_mk_rep K (ff i) (hff i)
convert hh1.units_smul a⁻¹
ext i
simp only [← ha, inv_smul_smul, Pi.smul_apply', Pi.inv_apply, Function.comp_apply]
· convert Dependent.mk _ _ h
· simp only [mk_rep, Function.comp_apply]
· exact fun i => rep_nonzero (f i)
| 0 |
import Mathlib.Algebra.Group.Equiv.TypeTags
import Mathlib.Data.ZMod.Quotient
import Mathlib.RingTheory.DedekindDomain.AdicValuation
#align_import ring_theory.dedekind_domain.selmer_group from "leanprover-community/mathlib"@"2032a878972d5672e7c27c957e7a6e297b044973"
set_option quotPrecheck false
local notation K "/" n => Kˣ ⧸ (powMonoidHom n : Kˣ →* Kˣ).range
namespace IsDedekindDomain
noncomputable section
open scoped Classical DiscreteValuation nonZeroDivisors
universe u v
variable {R : Type u} [CommRing R] [IsDedekindDomain R] {K : Type v} [Field K]
[Algebra R K] [IsFractionRing R K] (v : HeightOneSpectrum R)
namespace HeightOneSpectrum
def valuationOfNeZeroToFun (x : Kˣ) : Multiplicative ℤ :=
let hx := IsLocalization.sec R⁰ (x : K)
Multiplicative.ofAdd <|
(-(Associates.mk v.asIdeal).count (Associates.mk <| Ideal.span {hx.fst}).factors : ℤ) -
(-(Associates.mk v.asIdeal).count (Associates.mk <| Ideal.span {(hx.snd : R)}).factors : ℤ)
#align is_dedekind_domain.height_one_spectrum.valuation_of_ne_zero_to_fun IsDedekindDomain.HeightOneSpectrum.valuationOfNeZeroToFun
@[simp]
| Mathlib/RingTheory/DedekindDomain/SelmerGroup.lean | 93 | 102 | theorem valuationOfNeZeroToFun_eq (x : Kˣ) :
(v.valuationOfNeZeroToFun x : ℤₘ₀) = v.valuation (x : K) := by |
rw [show v.valuation (x : K) = _ * _ by rfl]
rw [Units.val_inv_eq_inv_val]
change _ = ite _ _ _ * (ite _ _ _)⁻¹
simp_rw [IsLocalization.toLocalizationMap_sec, SubmonoidClass.coe_subtype,
if_neg <| IsLocalization.sec_fst_ne_zero le_rfl x.ne_zero,
if_neg (nonZeroDivisors.coe_ne_zero _),
valuationOfNeZeroToFun, ofAdd_sub, ofAdd_neg, div_inv_eq_mul, WithZero.coe_mul,
WithZero.coe_inv, inv_inv]
| 0 |
import Mathlib.Combinatorics.Quiver.Cast
import Mathlib.Combinatorics.Quiver.Symmetric
import Mathlib.Data.Sigma.Basic
import Mathlib.Logic.Equiv.Basic
import Mathlib.Tactic.Common
#align_import combinatorics.quiver.covering from "leanprover-community/mathlib"@"188a411e916e1119e502dbe35b8b475716362401"
open Function Quiver
universe u v w
variable {U : Type _} [Quiver.{u + 1} U] {V : Type _} [Quiver.{v + 1} V] (φ : U ⥤q V) {W : Type _}
[Quiver.{w + 1} W] (ψ : V ⥤q W)
abbrev Quiver.Star (u : U) :=
Σ v : U, u ⟶ v
#align quiver.star Quiver.Star
protected abbrev Quiver.Star.mk {u v : U} (f : u ⟶ v) : Quiver.Star u :=
⟨_, f⟩
#align quiver.star.mk Quiver.Star.mk
abbrev Quiver.Costar (v : U) :=
Σ u : U, u ⟶ v
#align quiver.costar Quiver.Costar
protected abbrev Quiver.Costar.mk {u v : U} (f : u ⟶ v) : Quiver.Costar v :=
⟨_, f⟩
#align quiver.costar.mk Quiver.Costar.mk
@[simps]
def Prefunctor.star (u : U) : Quiver.Star u → Quiver.Star (φ.obj u) := fun F =>
Quiver.Star.mk (φ.map F.2)
#align prefunctor.star Prefunctor.star
@[simps]
def Prefunctor.costar (u : U) : Quiver.Costar u → Quiver.Costar (φ.obj u) := fun F =>
Quiver.Costar.mk (φ.map F.2)
#align prefunctor.costar Prefunctor.costar
@[simp]
theorem Prefunctor.star_apply {u v : U} (e : u ⟶ v) :
φ.star u (Quiver.Star.mk e) = Quiver.Star.mk (φ.map e) :=
rfl
#align prefunctor.star_apply Prefunctor.star_apply
@[simp]
theorem Prefunctor.costar_apply {u v : U} (e : u ⟶ v) :
φ.costar v (Quiver.Costar.mk e) = Quiver.Costar.mk (φ.map e) :=
rfl
#align prefunctor.costar_apply Prefunctor.costar_apply
theorem Prefunctor.star_comp (u : U) : (φ ⋙q ψ).star u = ψ.star (φ.obj u) ∘ φ.star u :=
rfl
#align prefunctor.star_comp Prefunctor.star_comp
theorem Prefunctor.costar_comp (u : U) : (φ ⋙q ψ).costar u = ψ.costar (φ.obj u) ∘ φ.costar u :=
rfl
#align prefunctor.costar_comp Prefunctor.costar_comp
protected structure Prefunctor.IsCovering : Prop where
star_bijective : ∀ u, Bijective (φ.star u)
costar_bijective : ∀ u, Bijective (φ.costar u)
#align prefunctor.is_covering Prefunctor.IsCovering
@[simp]
theorem Prefunctor.IsCovering.map_injective (hφ : φ.IsCovering) {u v : U} :
Injective fun f : u ⟶ v => φ.map f := by
rintro f g he
have : φ.star u (Quiver.Star.mk f) = φ.star u (Quiver.Star.mk g) := by simpa using he
simpa using (hφ.star_bijective u).left this
#align prefunctor.is_covering.map_injective Prefunctor.IsCovering.map_injective
theorem Prefunctor.IsCovering.comp (hφ : φ.IsCovering) (hψ : ψ.IsCovering) : (φ ⋙q ψ).IsCovering :=
⟨fun _ => (hψ.star_bijective _).comp (hφ.star_bijective _),
fun _ => (hψ.costar_bijective _).comp (hφ.costar_bijective _)⟩
#align prefunctor.is_covering.comp Prefunctor.IsCovering.comp
theorem Prefunctor.IsCovering.of_comp_right (hψ : ψ.IsCovering) (hφψ : (φ ⋙q ψ).IsCovering) :
φ.IsCovering :=
⟨fun _ => (Bijective.of_comp_iff' (hψ.star_bijective _) _).mp (hφψ.star_bijective _),
fun _ => (Bijective.of_comp_iff' (hψ.costar_bijective _) _).mp (hφψ.costar_bijective _)⟩
#align prefunctor.is_covering.of_comp_right Prefunctor.IsCovering.of_comp_right
| Mathlib/Combinatorics/Quiver/Covering.lean | 132 | 136 | theorem Prefunctor.IsCovering.of_comp_left (hφ : φ.IsCovering) (hφψ : (φ ⋙q ψ).IsCovering)
(φsur : Surjective φ.obj) : ψ.IsCovering := by |
refine ⟨fun v => ?_, fun v => ?_⟩ <;> obtain ⟨u, rfl⟩ := φsur v
exacts [(Bijective.of_comp_iff _ (hφ.star_bijective u)).mp (hφψ.star_bijective u),
(Bijective.of_comp_iff _ (hφ.costar_bijective u)).mp (hφψ.costar_bijective u)]
| 0 |
import Mathlib.Data.Set.Lattice
import Mathlib.Order.Directed
#align_import data.set.Union_lift from "leanprover-community/mathlib"@"5a4ea8453f128345f73cc656e80a49de2a54f481"
variable {α : Type*} {ι β : Sort _}
namespace Set
section UnionLift
@[nolint unusedArguments]
noncomputable def iUnionLift (S : ι → Set α) (f : ∀ i, S i → β)
(_ : ∀ (i j) (x : α) (hxi : x ∈ S i) (hxj : x ∈ S j), f i ⟨x, hxi⟩ = f j ⟨x, hxj⟩) (T : Set α)
(hT : T ⊆ iUnion S) (x : T) : β :=
let i := Classical.indefiniteDescription _ (mem_iUnion.1 (hT x.prop))
f i ⟨x, i.prop⟩
#align set.Union_lift Set.iUnionLift
variable {S : ι → Set α} {f : ∀ i, S i → β}
{hf : ∀ (i j) (x : α) (hxi : x ∈ S i) (hxj : x ∈ S j), f i ⟨x, hxi⟩ = f j ⟨x, hxj⟩} {T : Set α}
{hT : T ⊆ iUnion S} (hT' : T = iUnion S)
@[simp]
theorem iUnionLift_mk {i : ι} (x : S i) (hx : (x : α) ∈ T) :
iUnionLift S f hf T hT ⟨x, hx⟩ = f i x := hf _ i x _ _
#align set.Union_lift_mk Set.iUnionLift_mk
@[simp]
theorem iUnionLift_inclusion {i : ι} (x : S i) (h : S i ⊆ T) :
iUnionLift S f hf T hT (Set.inclusion h x) = f i x :=
iUnionLift_mk x _
#align set.Union_lift_inclusion Set.iUnionLift_inclusion
theorem iUnionLift_of_mem (x : T) {i : ι} (hx : (x : α) ∈ S i) :
iUnionLift S f hf T hT x = f i ⟨x, hx⟩ := by cases' x with x hx; exact hf _ _ _ _ _
#align set.Union_lift_of_mem Set.iUnionLift_of_mem
theorem preimage_iUnionLift (t : Set β) :
iUnionLift S f hf T hT ⁻¹' t =
inclusion hT ⁻¹' (⋃ i, inclusion (subset_iUnion S i) '' (f i ⁻¹' t)) := by
ext x
simp only [mem_preimage, mem_iUnion, mem_image]
constructor
· rcases mem_iUnion.1 (hT x.prop) with ⟨i, hi⟩
refine fun h => ⟨i, ⟨x, hi⟩, ?_, rfl⟩
rwa [iUnionLift_of_mem x hi] at h
· rintro ⟨i, ⟨y, hi⟩, h, hxy⟩
obtain rfl : y = x := congr_arg Subtype.val hxy
rwa [iUnionLift_of_mem x hi]
| Mathlib/Data/Set/UnionLift.lean | 96 | 100 | theorem iUnionLift_const (c : T) (ci : ∀ i, S i) (hci : ∀ i, (ci i : α) = c) (cβ : β)
(h : ∀ i, f i (ci i) = cβ) : iUnionLift S f hf T hT c = cβ := by |
let ⟨i, hi⟩ := Set.mem_iUnion.1 (hT c.prop)
have : ci i = ⟨c, hi⟩ := Subtype.ext (hci i)
rw [iUnionLift_of_mem _ hi, ← this, h]
| 0 |
import Mathlib.Data.Nat.Choose.Central
import Mathlib.Data.Nat.Factorization.Basic
import Mathlib.Data.Nat.Multiplicity
#align_import data.nat.choose.factorization from "leanprover-community/mathlib"@"dc9db541168768af03fe228703e758e649afdbfc"
namespace Nat
variable {p n k : ℕ}
theorem factorization_choose_le_log : (choose n k).factorization p ≤ log p n := by
by_cases h : (choose n k).factorization p = 0
· simp [h]
have hp : p.Prime := Not.imp_symm (choose n k).factorization_eq_zero_of_non_prime h
have hkn : k ≤ n := by
refine le_of_not_lt fun hnk => h ?_
simp [choose_eq_zero_of_lt hnk]
rw [factorization_def _ hp, @padicValNat_def _ ⟨hp⟩ _ (choose_pos hkn)]
simp only [hp.multiplicity_choose hkn (lt_add_one _), PartENat.get_natCast]
exact (Finset.card_filter_le _ _).trans (le_of_eq (Nat.card_Ico _ _))
#align nat.factorization_choose_le_log Nat.factorization_choose_le_log
theorem pow_factorization_choose_le (hn : 0 < n) : p ^ (choose n k).factorization p ≤ n :=
pow_le_of_le_log hn.ne' factorization_choose_le_log
#align nat.pow_factorization_choose_le Nat.pow_factorization_choose_le
theorem factorization_choose_le_one (p_large : n < p ^ 2) : (choose n k).factorization p ≤ 1 := by
apply factorization_choose_le_log.trans
rcases eq_or_ne n 0 with (rfl | hn0); · simp
exact Nat.lt_succ_iff.1 (log_lt_of_lt_pow hn0 p_large)
#align nat.factorization_choose_le_one Nat.factorization_choose_le_one
| Mathlib/Data/Nat/Choose/Factorization.lean | 61 | 88 | theorem factorization_choose_of_lt_three_mul (hp' : p ≠ 2) (hk : p ≤ k) (hk' : p ≤ n - k)
(hn : n < 3 * p) : (choose n k).factorization p = 0 := by |
cases' em' p.Prime with hp hp
· exact factorization_eq_zero_of_non_prime (choose n k) hp
cases' lt_or_le n k with hnk hkn
· simp [choose_eq_zero_of_lt hnk]
rw [factorization_def _ hp, @padicValNat_def _ ⟨hp⟩ _ (choose_pos hkn)]
simp only [hp.multiplicity_choose hkn (lt_add_one _), PartENat.get_natCast, Finset.card_eq_zero,
Finset.filter_eq_empty_iff, not_le]
intro i hi
rcases eq_or_lt_of_le (Finset.mem_Ico.mp hi).1 with (rfl | hi)
· rw [pow_one, ← add_lt_add_iff_left (2 * p), ← succ_mul, two_mul, add_add_add_comm]
exact
lt_of_le_of_lt
(add_le_add
(add_le_add_right (le_mul_of_one_le_right' ((one_le_div_iff hp.pos).mpr hk)) (k % p))
(add_le_add_right (le_mul_of_one_le_right' ((one_le_div_iff hp.pos).mpr hk'))
((n - k) % p)))
(by rwa [div_add_mod, div_add_mod, add_tsub_cancel_of_le hkn])
· replace hn : n < p ^ i := by
have : 3 ≤ p := lt_of_le_of_ne hp.two_le hp'.symm
calc
n < 3 * p := hn
_ ≤ p * p := mul_le_mul_right' this p
_ = p ^ 2 := (sq p).symm
_ ≤ p ^ i := pow_le_pow_right hp.one_lt.le hi
rwa [mod_eq_of_lt (lt_of_le_of_lt hkn hn), mod_eq_of_lt (lt_of_le_of_lt tsub_le_self hn),
add_tsub_cancel_of_le hkn]
| 0 |
import Mathlib.RingTheory.IntegralClosure
import Mathlib.RingTheory.Localization.Integral
#align_import ring_theory.integrally_closed from "leanprover-community/mathlib"@"d35b4ff446f1421bd551fafa4b8efd98ac3ac408"
open scoped nonZeroDivisors Polynomial
open Polynomial
abbrev IsIntegrallyClosedIn (R A : Type*) [CommRing R] [CommRing A] [Algebra R A] :=
IsIntegralClosure R R A
abbrev IsIntegrallyClosed (R : Type*) [CommRing R] := IsIntegrallyClosedIn R (FractionRing R)
#align is_integrally_closed IsIntegrallyClosed
section Iff
variable {R : Type*} [CommRing R]
variable {A B : Type*} [CommRing A] [CommRing B] [Algebra R A] [Algebra R B]
theorem AlgHom.isIntegrallyClosedIn (f : A →ₐ[R] B) (hf : Function.Injective f) :
IsIntegrallyClosedIn R B → IsIntegrallyClosedIn R A := by
rintro ⟨inj, cl⟩
refine ⟨Function.Injective.of_comp (f := f) ?_, fun hx => ?_, ?_⟩
· convert inj
aesop
· obtain ⟨y, fx_eq⟩ := cl.mp ((isIntegral_algHom_iff f hf).mpr hx)
aesop
· rintro ⟨y, rfl⟩
apply (isIntegral_algHom_iff f hf).mp
aesop
theorem AlgEquiv.isIntegrallyClosedIn (e : A ≃ₐ[R] B) :
IsIntegrallyClosedIn R A ↔ IsIntegrallyClosedIn R B :=
⟨AlgHom.isIntegrallyClosedIn e.symm e.symm.injective, AlgHom.isIntegrallyClosedIn e e.injective⟩
variable (K : Type*) [CommRing K] [Algebra R K] [IsFractionRing R K]
theorem isIntegrallyClosed_iff_isIntegrallyClosedIn :
IsIntegrallyClosed R ↔ IsIntegrallyClosedIn R K :=
(IsLocalization.algEquiv R⁰ _ _).isIntegrallyClosedIn
theorem isIntegrallyClosed_iff_isIntegralClosure : IsIntegrallyClosed R ↔ IsIntegralClosure R R K :=
isIntegrallyClosed_iff_isIntegrallyClosedIn K
#align is_integrally_closed_iff_is_integral_closure isIntegrallyClosed_iff_isIntegralClosure
theorem isIntegrallyClosedIn_iff {R A : Type*} [CommRing R] [CommRing A] [Algebra R A] :
IsIntegrallyClosedIn R A ↔
Function.Injective (algebraMap R A) ∧
∀ {x : A}, IsIntegral R x → ∃ y, algebraMap R A y = x := by
constructor
· rintro ⟨_, cl⟩
aesop
· rintro ⟨inj, cl⟩
refine ⟨inj, by aesop, ?_⟩
rintro ⟨y, rfl⟩
apply isIntegral_algebraMap
| Mathlib/RingTheory/IntegrallyClosed.lean | 124 | 127 | theorem isIntegrallyClosed_iff :
IsIntegrallyClosed R ↔ ∀ {x : K}, IsIntegral R x → ∃ y, algebraMap R K y = x := by |
simp [isIntegrallyClosed_iff_isIntegrallyClosedIn K, isIntegrallyClosedIn_iff,
IsFractionRing.injective R K]
| 0 |
import Mathlib.Analysis.SpecialFunctions.Integrals
import Mathlib.Topology.MetricSpace.Contracting
#align_import analysis.ODE.picard_lindelof from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982"
open Filter Function Set Metric TopologicalSpace intervalIntegral MeasureTheory
open MeasureTheory.MeasureSpace (volume)
open scoped Filter Topology NNReal ENNReal Nat Interval
noncomputable section
variable {E : Type*} [NormedAddCommGroup E] [NormedSpace ℝ E]
structure IsPicardLindelof {E : Type*} [NormedAddCommGroup E] (v : ℝ → E → E) (tMin t₀ tMax : ℝ)
(x₀ : E) (L : ℝ≥0) (R C : ℝ) : Prop where
ht₀ : t₀ ∈ Icc tMin tMax
hR : 0 ≤ R
lipschitz : ∀ t ∈ Icc tMin tMax, LipschitzOnWith L (v t) (closedBall x₀ R)
cont : ∀ x ∈ closedBall x₀ R, ContinuousOn (fun t : ℝ => v t x) (Icc tMin tMax)
norm_le : ∀ t ∈ Icc tMin tMax, ∀ x ∈ closedBall x₀ R, ‖v t x‖ ≤ C
C_mul_le_R : (C : ℝ) * max (tMax - t₀) (t₀ - tMin) ≤ R
#align is_picard_lindelof IsPicardLindelof
structure PicardLindelof (E : Type*) [NormedAddCommGroup E] [NormedSpace ℝ E] where
toFun : ℝ → E → E
(tMin tMax : ℝ)
t₀ : Icc tMin tMax
x₀ : E
(C R L : ℝ≥0)
isPicardLindelof : IsPicardLindelof toFun tMin t₀ tMax x₀ L R C
#align picard_lindelof PicardLindelof
namespace PicardLindelof
variable (v : PicardLindelof E)
instance : CoeFun (PicardLindelof E) fun _ => ℝ → E → E :=
⟨toFun⟩
instance : Inhabited (PicardLindelof E) :=
⟨⟨0, 0, 0, ⟨0, le_rfl, le_rfl⟩, 0, 0, 0, 0,
{ ht₀ := by rw [Subtype.coe_mk, Icc_self]; exact mem_singleton _
hR := le_rfl
lipschitz := fun t _ => (LipschitzWith.const 0).lipschitzOnWith _
cont := fun _ _ => by simpa only [Pi.zero_apply] using continuousOn_const
norm_le := fun t _ x _ => norm_zero.le
C_mul_le_R := (zero_mul _).le }⟩⟩
theorem tMin_le_tMax : v.tMin ≤ v.tMax :=
v.t₀.2.1.trans v.t₀.2.2
#align picard_lindelof.t_min_le_t_max PicardLindelof.tMin_le_tMax
protected theorem nonempty_Icc : (Icc v.tMin v.tMax).Nonempty :=
nonempty_Icc.2 v.tMin_le_tMax
#align picard_lindelof.nonempty_Icc PicardLindelof.nonempty_Icc
protected theorem lipschitzOnWith {t} (ht : t ∈ Icc v.tMin v.tMax) :
LipschitzOnWith v.L (v t) (closedBall v.x₀ v.R) :=
v.isPicardLindelof.lipschitz t ht
#align picard_lindelof.lipschitz_on_with PicardLindelof.lipschitzOnWith
protected theorem continuousOn :
ContinuousOn (uncurry v) (Icc v.tMin v.tMax ×ˢ closedBall v.x₀ v.R) :=
have : ContinuousOn (uncurry (flip v)) (closedBall v.x₀ v.R ×ˢ Icc v.tMin v.tMax) :=
continuousOn_prod_of_continuousOn_lipschitzOnWith _ v.L v.isPicardLindelof.cont
v.isPicardLindelof.lipschitz
this.comp continuous_swap.continuousOn (preimage_swap_prod _ _).symm.subset
#align picard_lindelof.continuous_on PicardLindelof.continuousOn
theorem norm_le {t : ℝ} (ht : t ∈ Icc v.tMin v.tMax) {x : E} (hx : x ∈ closedBall v.x₀ v.R) :
‖v t x‖ ≤ v.C :=
v.isPicardLindelof.norm_le _ ht _ hx
#align picard_lindelof.norm_le PicardLindelof.norm_le
def tDist : ℝ :=
max (v.tMax - v.t₀) (v.t₀ - v.tMin)
#align picard_lindelof.t_dist PicardLindelof.tDist
theorem tDist_nonneg : 0 ≤ v.tDist :=
le_max_iff.2 <| Or.inl <| sub_nonneg.2 v.t₀.2.2
#align picard_lindelof.t_dist_nonneg PicardLindelof.tDist_nonneg
| Mathlib/Analysis/ODE/PicardLindelof.lean | 127 | 133 | theorem dist_t₀_le (t : Icc v.tMin v.tMax) : dist t v.t₀ ≤ v.tDist := by |
rw [Subtype.dist_eq, Real.dist_eq]
rcases le_total t v.t₀ with ht | ht
· rw [abs_of_nonpos (sub_nonpos.2 <| Subtype.coe_le_coe.2 ht), neg_sub]
exact (sub_le_sub_left t.2.1 _).trans (le_max_right _ _)
· rw [abs_of_nonneg (sub_nonneg.2 <| Subtype.coe_le_coe.2 ht)]
exact (sub_le_sub_right t.2.2 _).trans (le_max_left _ _)
| 0 |
import Mathlib.MeasureTheory.MeasurableSpace.Basic
import Mathlib.Data.Set.MemPartition
import Mathlib.Order.Filter.CountableSeparatingOn
open Set MeasureTheory
namespace MeasurableSpace
variable {α β : Type*}
class CountablyGenerated (α : Type*) [m : MeasurableSpace α] : Prop where
isCountablyGenerated : ∃ b : Set (Set α), b.Countable ∧ m = generateFrom b
#align measurable_space.countably_generated MeasurableSpace.CountablyGenerated
def countableGeneratingSet (α : Type*) [MeasurableSpace α] [h : CountablyGenerated α] :
Set (Set α) :=
insert ∅ h.isCountablyGenerated.choose
lemma countable_countableGeneratingSet [MeasurableSpace α] [h : CountablyGenerated α] :
Set.Countable (countableGeneratingSet α) :=
Countable.insert _ h.isCountablyGenerated.choose_spec.1
lemma generateFrom_countableGeneratingSet [m : MeasurableSpace α] [h : CountablyGenerated α] :
generateFrom (countableGeneratingSet α) = m :=
(generateFrom_insert_empty _).trans <| h.isCountablyGenerated.choose_spec.2.symm
lemma empty_mem_countableGeneratingSet [MeasurableSpace α] [CountablyGenerated α] :
∅ ∈ countableGeneratingSet α := mem_insert _ _
lemma nonempty_countableGeneratingSet [MeasurableSpace α] [CountablyGenerated α] :
Set.Nonempty (countableGeneratingSet α) :=
⟨∅, mem_insert _ _⟩
lemma measurableSet_countableGeneratingSet [MeasurableSpace α] [CountablyGenerated α]
{s : Set α} (hs : s ∈ countableGeneratingSet α) :
MeasurableSet s := by
rw [← generateFrom_countableGeneratingSet (α := α)]
exact measurableSet_generateFrom hs
def natGeneratingSequence (α : Type*) [MeasurableSpace α] [CountablyGenerated α] : ℕ → (Set α) :=
enumerateCountable (countable_countableGeneratingSet (α := α)) ∅
lemma generateFrom_natGeneratingSequence (α : Type*) [m : MeasurableSpace α]
[CountablyGenerated α] : generateFrom (range (natGeneratingSequence _)) = m := by
rw [natGeneratingSequence, range_enumerateCountable_of_mem _ empty_mem_countableGeneratingSet,
generateFrom_countableGeneratingSet]
lemma measurableSet_natGeneratingSequence [MeasurableSpace α] [CountablyGenerated α] (n : ℕ) :
MeasurableSet (natGeneratingSequence α n) :=
measurableSet_countableGeneratingSet $ Set.enumerateCountable_mem _
empty_mem_countableGeneratingSet n
theorem CountablyGenerated.comap [m : MeasurableSpace β] [h : CountablyGenerated β] (f : α → β) :
@CountablyGenerated α (.comap f m) := by
rcases h with ⟨⟨b, hbc, rfl⟩⟩
rw [comap_generateFrom]
letI := generateFrom (preimage f '' b)
exact ⟨_, hbc.image _, rfl⟩
| Mathlib/MeasureTheory/MeasurableSpace/CountablyGenerated.lean | 103 | 107 | theorem CountablyGenerated.sup {m₁ m₂ : MeasurableSpace β} (h₁ : @CountablyGenerated β m₁)
(h₂ : @CountablyGenerated β m₂) : @CountablyGenerated β (m₁ ⊔ m₂) := by |
rcases h₁ with ⟨⟨b₁, hb₁c, rfl⟩⟩
rcases h₂ with ⟨⟨b₂, hb₂c, rfl⟩⟩
exact @mk _ (_ ⊔ _) ⟨_, hb₁c.union hb₂c, generateFrom_sup_generateFrom⟩
| 0 |
import Mathlib.Data.List.Lex
import Mathlib.Data.Char
import Mathlib.Tactic.AdaptationNote
import Mathlib.Algebra.Order.Group.Nat
#align_import data.string.basic from "leanprover-community/mathlib"@"d13b3a4a392ea7273dfa4727dbd1892e26cfd518"
namespace String
def ltb (s₁ s₂ : Iterator) : Bool :=
if s₂.hasNext then
if s₁.hasNext then
if s₁.curr = s₂.curr then
ltb s₁.next s₂.next
else s₁.curr < s₂.curr
else true
else false
#align string.ltb String.ltb
instance LT' : LT String :=
⟨fun s₁ s₂ ↦ ltb s₁.iter s₂.iter⟩
#align string.has_lt' String.LT'
instance decidableLT : @DecidableRel String (· < ·) := by
simp only [LT']
infer_instance -- short-circuit type class inference
#align string.decidable_lt String.decidableLT
def ltb.inductionOn.{u} {motive : Iterator → Iterator → Sort u} (it₁ it₂ : Iterator)
(ind : ∀ s₁ s₂ i₁ i₂, Iterator.hasNext ⟨s₂, i₂⟩ → Iterator.hasNext ⟨s₁, i₁⟩ →
get s₁ i₁ = get s₂ i₂ → motive (Iterator.next ⟨s₁, i₁⟩) (Iterator.next ⟨s₂, i₂⟩) →
motive ⟨s₁, i₁⟩ ⟨s₂, i₂⟩)
(eq : ∀ s₁ s₂ i₁ i₂, Iterator.hasNext ⟨s₂, i₂⟩ → Iterator.hasNext ⟨s₁, i₁⟩ →
¬ get s₁ i₁ = get s₂ i₂ → motive ⟨s₁, i₁⟩ ⟨s₂, i₂⟩)
(base₁ : ∀ s₁ s₂ i₁ i₂, Iterator.hasNext ⟨s₂, i₂⟩ → ¬ Iterator.hasNext ⟨s₁, i₁⟩ →
motive ⟨s₁, i₁⟩ ⟨s₂, i₂⟩)
(base₂ : ∀ s₁ s₂ i₁ i₂, ¬ Iterator.hasNext ⟨s₂, i₂⟩ → motive ⟨s₁, i₁⟩ ⟨s₂, i₂⟩) :
motive it₁ it₂ :=
if h₂ : it₂.hasNext then
if h₁ : it₁.hasNext then
if heq : it₁.curr = it₂.curr then
ind it₁.s it₂.s it₁.i it₂.i h₂ h₁ heq (inductionOn it₁.next it₂.next ind eq base₁ base₂)
else eq it₁.s it₂.s it₁.i it₂.i h₂ h₁ heq
else base₁ it₁.s it₂.s it₁.i it₂.i h₂ h₁
else base₂ it₁.s it₂.s it₁.i it₂.i h₂
| Mathlib/Data/String/Basic.lean | 60 | 74 | theorem ltb_cons_addChar (c : Char) (cs₁ cs₂ : List Char) (i₁ i₂ : Pos) :
ltb ⟨⟨c :: cs₁⟩, i₁ + c⟩ ⟨⟨c :: cs₂⟩, i₂ + c⟩ = ltb ⟨⟨cs₁⟩, i₁⟩ ⟨⟨cs₂⟩, i₂⟩ := by |
apply ltb.inductionOn ⟨⟨cs₁⟩, i₁⟩ ⟨⟨cs₂⟩, i₂⟩ (motive := fun ⟨⟨cs₁⟩, i₁⟩ ⟨⟨cs₂⟩, i₂⟩ ↦
ltb ⟨⟨c :: cs₁⟩, i₁ + c⟩ ⟨⟨c :: cs₂⟩, i₂ + c⟩ =
ltb ⟨⟨cs₁⟩, i₁⟩ ⟨⟨cs₂⟩, i₂⟩) <;> simp only <;>
intro ⟨cs₁⟩ ⟨cs₂⟩ i₁ i₂ <;>
intros <;>
(conv => lhs; unfold ltb) <;> (conv => rhs; unfold ltb) <;>
simp only [Iterator.hasNext_cons_addChar, ite_false, ite_true, *]
· rename_i h₂ h₁ heq ih
simp only [Iterator.next, next, heq, Iterator.curr, get_cons_addChar, ite_true] at ih ⊢
repeat rw [Pos.addChar_right_comm _ c]
exact ih
· rename_i h₂ h₁ hne
simp [Iterator.curr, get_cons_addChar, hne]
| 0 |
import Mathlib.Analysis.Calculus.ContDiff.Basic
import Mathlib.Analysis.Calculus.Deriv.Mul
import Mathlib.Analysis.Calculus.Deriv.Shift
import Mathlib.Analysis.Calculus.IteratedDeriv.Defs
variable
{𝕜 : Type*} [NontriviallyNormedField 𝕜]
{F : Type*} [NormedAddCommGroup F] [NormedSpace 𝕜 F]
{R : Type*} [Semiring R] [Module R F] [SMulCommClass 𝕜 R F] [ContinuousConstSMul R F]
{n : ℕ} {x : 𝕜} {s : Set 𝕜} (hx : x ∈ s) (h : UniqueDiffOn 𝕜 s) {f g : 𝕜 → F}
theorem iteratedDerivWithin_add (hf : ContDiffOn 𝕜 n f s) (hg : ContDiffOn 𝕜 n g s) :
iteratedDerivWithin n (f + g) s x =
iteratedDerivWithin n f s x + iteratedDerivWithin n g s x := by
simp_rw [iteratedDerivWithin, iteratedFDerivWithin_add_apply hf hg h hx,
ContinuousMultilinearMap.add_apply]
theorem iteratedDerivWithin_congr (hfg : Set.EqOn f g s) :
Set.EqOn (iteratedDerivWithin n f s) (iteratedDerivWithin n g s) s := by
induction n generalizing f g with
| zero => rwa [iteratedDerivWithin_zero]
| succ n IH =>
intro y hy
have : UniqueDiffWithinAt 𝕜 s y := h.uniqueDiffWithinAt hy
rw [iteratedDerivWithin_succ this, iteratedDerivWithin_succ this]
exact derivWithin_congr (IH hfg) (IH hfg hy)
theorem iteratedDerivWithin_const_add (hn : 0 < n) (c : F) :
iteratedDerivWithin n (fun z => c + f z) s x = iteratedDerivWithin n f s x := by
obtain ⟨n, rfl⟩ := n.exists_eq_succ_of_ne_zero hn.ne'
rw [iteratedDerivWithin_succ' h hx, iteratedDerivWithin_succ' h hx]
refine iteratedDerivWithin_congr h ?_ hx
intro y hy
exact derivWithin_const_add (h.uniqueDiffWithinAt hy) _
theorem iteratedDerivWithin_const_neg (hn : 0 < n) (c : F) :
iteratedDerivWithin n (fun z => c - f z) s x = iteratedDerivWithin n (fun z => -f z) s x := by
obtain ⟨n, rfl⟩ := n.exists_eq_succ_of_ne_zero hn.ne'
rw [iteratedDerivWithin_succ' h hx, iteratedDerivWithin_succ' h hx]
refine iteratedDerivWithin_congr h ?_ hx
intro y hy
have : UniqueDiffWithinAt 𝕜 s y := h.uniqueDiffWithinAt hy
rw [derivWithin.neg this]
exact derivWithin_const_sub this _
theorem iteratedDerivWithin_const_smul (c : R) (hf : ContDiffOn 𝕜 n f s) :
iteratedDerivWithin n (c • f) s x = c • iteratedDerivWithin n f s x := by
simp_rw [iteratedDerivWithin]
rw [iteratedFDerivWithin_const_smul_apply hf h hx]
simp only [ContinuousMultilinearMap.smul_apply]
theorem iteratedDerivWithin_const_mul (c : 𝕜) {f : 𝕜 → 𝕜} (hf : ContDiffOn 𝕜 n f s) :
iteratedDerivWithin n (fun z => c * f z) s x = c * iteratedDerivWithin n f s x := by
simpa using iteratedDerivWithin_const_smul (F := 𝕜) hx h c hf
variable (f) in
theorem iteratedDerivWithin_neg :
iteratedDerivWithin n (-f) s x = -iteratedDerivWithin n f s x := by
rw [iteratedDerivWithin, iteratedDerivWithin, iteratedFDerivWithin_neg_apply h hx,
ContinuousMultilinearMap.neg_apply]
variable (f) in
theorem iteratedDerivWithin_neg' :
iteratedDerivWithin n (fun z => -f z) s x = -iteratedDerivWithin n f s x :=
iteratedDerivWithin_neg hx h f
theorem iteratedDerivWithin_sub (hf : ContDiffOn 𝕜 n f s) (hg : ContDiffOn 𝕜 n g s) :
iteratedDerivWithin n (f - g) s x =
iteratedDerivWithin n f s x - iteratedDerivWithin n g s x := by
rw [sub_eq_add_neg, sub_eq_add_neg, Pi.neg_def, iteratedDerivWithin_add hx h hf hg.neg,
iteratedDerivWithin_neg' hx h]
| Mathlib/Analysis/Calculus/IteratedDeriv/Lemmas.lean | 85 | 100 | theorem iteratedDeriv_const_smul {n : ℕ} {f : 𝕜 → F} (h : ContDiff 𝕜 n f) (c : 𝕜) :
iteratedDeriv n (fun x => f (c * x)) = fun x => c ^ n • iteratedDeriv n f (c * x) := by |
induction n with
| zero => simp
| succ n ih =>
funext x
have h₀ : DifferentiableAt 𝕜 (iteratedDeriv n f) (c * x) :=
h.differentiable_iteratedDeriv n (Nat.cast_lt.mpr n.lt_succ_self) |>.differentiableAt
have h₁ : DifferentiableAt 𝕜 (fun x => iteratedDeriv n f (c * x)) x := by
rw [← Function.comp_def]
apply DifferentiableAt.comp
· exact h.differentiable_iteratedDeriv n (Nat.cast_lt.mpr n.lt_succ_self) |>.differentiableAt
· exact differentiableAt_id'.const_mul _
rw [iteratedDeriv_succ, ih h.of_succ, deriv_const_smul _ h₁, iteratedDeriv_succ,
← Function.comp_def, deriv.scomp x h₀ (differentiableAt_id'.const_mul _),
deriv_const_mul _ differentiableAt_id', deriv_id'', smul_smul, mul_one, pow_succ]
| 0 |
set_option autoImplicit true
namespace Array
@[simp]
theorem extract_eq_nil_of_start_eq_end {a : Array α} :
a.extract i i = #[] := by
refine extract_empty_of_stop_le_start a ?h
exact Nat.le_refl i
theorem extract_append_left {a b : Array α} {i j : Nat} (h : j ≤ a.size) :
(a ++ b).extract i j = a.extract i j := by
apply ext
· simp only [size_extract, size_append]
omega
· intro h1 h2 h3
rw [get_extract, get_append_left, get_extract]
| Mathlib/Data/Array/ExtractLemmas.lean | 29 | 38 | theorem extract_append_right {a b : Array α} {i j : Nat} (h : a.size ≤ i) :
(a ++ b).extract i j = b.extract (i - a.size) (j - a.size) := by |
apply ext
· rw [size_extract, size_extract, size_append]
omega
· intro k hi h2
rw [get_extract, get_extract,
get_append_right (show size a ≤ i + k by omega)]
congr
omega
| 0 |
import Mathlib.Analysis.SpecialFunctions.ExpDeriv
import Mathlib.Analysis.SpecialFunctions.Complex.Circle
import Mathlib.Analysis.InnerProductSpace.l2Space
import Mathlib.MeasureTheory.Function.ContinuousMapDense
import Mathlib.MeasureTheory.Function.L2Space
import Mathlib.MeasureTheory.Group.Integral
import Mathlib.MeasureTheory.Integral.Periodic
import Mathlib.Topology.ContinuousFunction.StoneWeierstrass
import Mathlib.MeasureTheory.Integral.FundThmCalculus
#align_import analysis.fourier.add_circle from "leanprover-community/mathlib"@"8f9fea08977f7e450770933ee6abb20733b47c92"
noncomputable section
open scoped ENNReal ComplexConjugate Real
open TopologicalSpace ContinuousMap MeasureTheory MeasureTheory.Measure Algebra Submodule Set
variable {T : ℝ}
open AddCircle
section Monomials
def fourier (n : ℤ) : C(AddCircle T, ℂ) where
toFun x := toCircle (n • x :)
continuous_toFun := continuous_induced_dom.comp <| continuous_toCircle.comp <| continuous_zsmul _
#align fourier fourier
@[simp]
theorem fourier_apply {n : ℤ} {x : AddCircle T} : fourier n x = toCircle (n • x :) :=
rfl
#align fourier_apply fourier_apply
-- @[simp] -- Porting note: simp normal form is `fourier_coe_apply'`
theorem fourier_coe_apply {n : ℤ} {x : ℝ} :
fourier n (x : AddCircle T) = Complex.exp (2 * π * Complex.I * n * x / T) := by
rw [fourier_apply, ← QuotientAddGroup.mk_zsmul, toCircle, Function.Periodic.lift_coe,
expMapCircle_apply, Complex.ofReal_mul, Complex.ofReal_div, Complex.ofReal_mul, zsmul_eq_mul,
Complex.ofReal_mul, Complex.ofReal_intCast]
norm_num
congr 1; ring
#align fourier_coe_apply fourier_coe_apply
@[simp]
theorem fourier_coe_apply' {n : ℤ} {x : ℝ} :
toCircle (n • (x : AddCircle T) :) = Complex.exp (2 * π * Complex.I * n * x / T) := by
rw [← fourier_apply]; exact fourier_coe_apply
-- @[simp] -- Porting note: simp normal form is `fourier_zero'`
theorem fourier_zero {x : AddCircle T} : fourier 0 x = 1 := by
induction x using QuotientAddGroup.induction_on'
simp only [fourier_coe_apply]
norm_num
#align fourier_zero fourier_zero
@[simp]
theorem fourier_zero' {x : AddCircle T} : @toCircle T 0 = (1 : ℂ) := by
have : fourier 0 x = @toCircle T 0 := by rw [fourier_apply, zero_smul]
rw [← this]; exact fourier_zero
-- @[simp] -- Porting note: simp normal form is *also* `fourier_zero'`
theorem fourier_eval_zero (n : ℤ) : fourier n (0 : AddCircle T) = 1 := by
rw [← QuotientAddGroup.mk_zero, fourier_coe_apply, Complex.ofReal_zero, mul_zero,
zero_div, Complex.exp_zero]
#align fourier_eval_zero fourier_eval_zero
-- @[simp] -- Porting note (#10618): simp can prove this
theorem fourier_one {x : AddCircle T} : fourier 1 x = toCircle x := by rw [fourier_apply, one_zsmul]
#align fourier_one fourier_one
-- @[simp] -- Porting note: simp normal form is `fourier_neg'`
theorem fourier_neg {n : ℤ} {x : AddCircle T} : fourier (-n) x = conj (fourier n x) := by
induction x using QuotientAddGroup.induction_on'
simp_rw [fourier_apply, toCircle]
rw [← QuotientAddGroup.mk_zsmul, ← QuotientAddGroup.mk_zsmul]
simp_rw [Function.Periodic.lift_coe, ← coe_inv_circle_eq_conj, ← expMapCircle_neg,
neg_smul, mul_neg]
#align fourier_neg fourier_neg
@[simp]
theorem fourier_neg' {n : ℤ} {x : AddCircle T} : @toCircle T (-(n • x)) = conj (fourier n x) := by
rw [← neg_smul, ← fourier_apply]; exact fourier_neg
-- @[simp] -- Porting note: simp normal form is `fourier_add'`
theorem fourier_add {m n : ℤ} {x : AddCircle T} : fourier (m+n) x = fourier m x * fourier n x := by
simp_rw [fourier_apply, add_zsmul, toCircle_add, coe_mul_unitSphere]
#align fourier_add fourier_add
@[simp]
theorem fourier_add' {m n : ℤ} {x : AddCircle T} :
toCircle ((m + n) • x :) = fourier m x * fourier n x := by
rw [← fourier_apply]; exact fourier_add
theorem fourier_norm [Fact (0 < T)] (n : ℤ) : ‖@fourier T n‖ = 1 := by
rw [ContinuousMap.norm_eq_iSup_norm]
have : ∀ x : AddCircle T, ‖fourier n x‖ = 1 := fun x => abs_coe_circle _
simp_rw [this]
exact @ciSup_const _ _ _ Zero.instNonempty _
#align fourier_norm fourier_norm
| Mathlib/Analysis/Fourier/AddCircle.lean | 184 | 193 | theorem fourier_add_half_inv_index {n : ℤ} (hn : n ≠ 0) (hT : 0 < T) (x : AddCircle T) :
@fourier T n (x + ↑(T / 2 / n)) = -fourier n x := by |
rw [fourier_apply, zsmul_add, ← QuotientAddGroup.mk_zsmul, toCircle_add, coe_mul_unitSphere]
have : (n : ℂ) ≠ 0 := by simpa using hn
have : (@toCircle T (n • (T / 2 / n) : ℝ) : ℂ) = -1 := by
rw [zsmul_eq_mul, toCircle, Function.Periodic.lift_coe, expMapCircle_apply]
replace hT := Complex.ofReal_ne_zero.mpr hT.ne'
convert Complex.exp_pi_mul_I using 3
field_simp; ring
rw [this]; simp
| 0 |
import Mathlib.Analysis.Convex.Combination
import Mathlib.Analysis.Convex.Function
import Mathlib.Tactic.FieldSimp
#align_import analysis.convex.jensen from "leanprover-community/mathlib"@"bfad3f455b388fbcc14c49d0cac884f774f14d20"
open Finset LinearMap Set
open scoped Classical
open Convex Pointwise
variable {𝕜 E F β ι : Type*}
section Jensen
variable [LinearOrderedField 𝕜] [AddCommGroup E] [OrderedAddCommGroup β] [Module 𝕜 E] [Module 𝕜 β]
[OrderedSMul 𝕜 β] {s : Set E} {f : E → β} {t : Finset ι} {w : ι → 𝕜} {p : ι → E} {v : 𝕜} {q : E}
| Mathlib/Analysis/Convex/Jensen.lean | 52 | 58 | theorem ConvexOn.map_centerMass_le (hf : ConvexOn 𝕜 s f) (h₀ : ∀ i ∈ t, 0 ≤ w i)
(h₁ : 0 < ∑ i ∈ t, w i) (hmem : ∀ i ∈ t, p i ∈ s) :
f (t.centerMass w p) ≤ t.centerMass w (f ∘ p) := by |
have hmem' : ∀ i ∈ t, (p i, (f ∘ p) i) ∈ { p : E × β | p.1 ∈ s ∧ f p.1 ≤ p.2 } := fun i hi =>
⟨hmem i hi, le_rfl⟩
convert (hf.convex_epigraph.centerMass_mem h₀ h₁ hmem').2 <;>
simp only [centerMass, Function.comp, Prod.smul_fst, Prod.fst_sum, Prod.smul_snd, Prod.snd_sum]
| 0 |
import Mathlib.Algebra.Algebra.Defs
import Mathlib.Algebra.Order.Group.Basic
import Mathlib.Algebra.Order.Ring.Basic
import Mathlib.RingTheory.Localization.Basic
import Mathlib.SetTheory.Game.Birthday
import Mathlib.SetTheory.Surreal.Basic
#align_import set_theory.surreal.dyadic from "leanprover-community/mathlib"@"92ca63f0fb391a9ca5f22d2409a6080e786d99f7"
universe u
namespace SetTheory
namespace PGame
def powHalf : ℕ → PGame
| 0 => 1
| n + 1 => ⟨PUnit, PUnit, 0, fun _ => powHalf n⟩
#align pgame.pow_half SetTheory.PGame.powHalf
@[simp]
theorem powHalf_zero : powHalf 0 = 1 :=
rfl
#align pgame.pow_half_zero SetTheory.PGame.powHalf_zero
theorem powHalf_leftMoves (n) : (powHalf n).LeftMoves = PUnit := by cases n <;> rfl
#align pgame.pow_half_left_moves SetTheory.PGame.powHalf_leftMoves
theorem powHalf_zero_rightMoves : (powHalf 0).RightMoves = PEmpty :=
rfl
#align pgame.pow_half_zero_right_moves SetTheory.PGame.powHalf_zero_rightMoves
theorem powHalf_succ_rightMoves (n) : (powHalf (n + 1)).RightMoves = PUnit :=
rfl
#align pgame.pow_half_succ_right_moves SetTheory.PGame.powHalf_succ_rightMoves
@[simp]
theorem powHalf_moveLeft (n i) : (powHalf n).moveLeft i = 0 := by cases n <;> cases i <;> rfl
#align pgame.pow_half_move_left SetTheory.PGame.powHalf_moveLeft
@[simp]
theorem powHalf_succ_moveRight (n i) : (powHalf (n + 1)).moveRight i = powHalf n :=
rfl
#align pgame.pow_half_succ_move_right SetTheory.PGame.powHalf_succ_moveRight
instance uniquePowHalfLeftMoves (n) : Unique (powHalf n).LeftMoves := by
cases n <;> exact PUnit.unique
#align pgame.unique_pow_half_left_moves SetTheory.PGame.uniquePowHalfLeftMoves
instance isEmpty_powHalf_zero_rightMoves : IsEmpty (powHalf 0).RightMoves :=
inferInstanceAs (IsEmpty PEmpty)
#align pgame.is_empty_pow_half_zero_right_moves SetTheory.PGame.isEmpty_powHalf_zero_rightMoves
instance uniquePowHalfSuccRightMoves (n) : Unique (powHalf (n + 1)).RightMoves :=
PUnit.unique
#align pgame.unique_pow_half_succ_right_moves SetTheory.PGame.uniquePowHalfSuccRightMoves
@[simp]
theorem birthday_half : birthday (powHalf 1) = 2 := by
rw [birthday_def]; simp
#align pgame.birthday_half SetTheory.PGame.birthday_half
| Mathlib/SetTheory/Surreal/Dyadic.lean | 90 | 95 | theorem numeric_powHalf (n) : (powHalf n).Numeric := by |
induction' n with n hn
· exact numeric_one
· constructor
· simpa using hn.moveLeft_lt default
· exact ⟨fun _ => numeric_zero, fun _ => hn⟩
| 0 |
import Mathlib.Analysis.InnerProductSpace.Dual
import Mathlib.Analysis.Calculus.FDeriv.Basic
import Mathlib.Analysis.Calculus.Deriv.Basic
open Topology InnerProductSpace Set
noncomputable section
variable {𝕜 F : Type*} [RCLike 𝕜]
variable [NormedAddCommGroup F] [InnerProductSpace 𝕜 F] [CompleteSpace F]
variable {f : F → 𝕜} {f' x : F}
def HasGradientAtFilter (f : F → 𝕜) (f' x : F) (L : Filter F) :=
HasFDerivAtFilter f (toDual 𝕜 F f') x L
def HasGradientWithinAt (f : F → 𝕜) (f' : F) (s : Set F) (x : F) :=
HasGradientAtFilter f f' x (𝓝[s] x)
def HasGradientAt (f : F → 𝕜) (f' x : F) :=
HasGradientAtFilter f f' x (𝓝 x)
def gradientWithin (f : F → 𝕜) (s : Set F) (x : F) : F :=
(toDual 𝕜 F).symm (fderivWithin 𝕜 f s x)
def gradient (f : F → 𝕜) (x : F) : F :=
(toDual 𝕜 F).symm (fderiv 𝕜 f x)
@[inherit_doc]
scoped[Gradient] notation "∇" => gradient
local notation "⟪" x ", " y "⟫" => @inner 𝕜 _ _ x y
open scoped Gradient
variable {s : Set F} {L : Filter F}
theorem hasGradientWithinAt_iff_hasFDerivWithinAt {s : Set F} :
HasGradientWithinAt f f' s x ↔ HasFDerivWithinAt f (toDual 𝕜 F f') s x :=
Iff.rfl
theorem hasFDerivWithinAt_iff_hasGradientWithinAt {frechet : F →L[𝕜] 𝕜} {s : Set F} :
HasFDerivWithinAt f frechet s x ↔ HasGradientWithinAt f ((toDual 𝕜 F).symm frechet) s x := by
rw [hasGradientWithinAt_iff_hasFDerivWithinAt, (toDual 𝕜 F).apply_symm_apply frechet]
theorem hasGradientAt_iff_hasFDerivAt :
HasGradientAt f f' x ↔ HasFDerivAt f (toDual 𝕜 F f') x :=
Iff.rfl
theorem hasFDerivAt_iff_hasGradientAt {frechet : F →L[𝕜] 𝕜} :
HasFDerivAt f frechet x ↔ HasGradientAt f ((toDual 𝕜 F).symm frechet) x := by
rw [hasGradientAt_iff_hasFDerivAt, (toDual 𝕜 F).apply_symm_apply frechet]
alias ⟨HasGradientWithinAt.hasFDerivWithinAt, _⟩ := hasGradientWithinAt_iff_hasFDerivWithinAt
alias ⟨HasFDerivWithinAt.hasGradientWithinAt, _⟩ := hasFDerivWithinAt_iff_hasGradientWithinAt
alias ⟨HasGradientAt.hasFDerivAt, _⟩ := hasGradientAt_iff_hasFDerivAt
alias ⟨HasFDerivAt.hasGradientAt, _⟩ := hasFDerivAt_iff_hasGradientAt
theorem gradient_eq_zero_of_not_differentiableAt (h : ¬DifferentiableAt 𝕜 f x) : ∇ f x = 0 := by
rw [gradient, fderiv_zero_of_not_differentiableAt h, map_zero]
theorem HasGradientAt.unique {gradf gradg : F}
(hf : HasGradientAt f gradf x) (hg : HasGradientAt f gradg x) :
gradf = gradg :=
(toDual 𝕜 F).injective (hf.hasFDerivAt.unique hg.hasFDerivAt)
theorem DifferentiableAt.hasGradientAt (h : DifferentiableAt 𝕜 f x) :
HasGradientAt f (∇ f x) x := by
rw [hasGradientAt_iff_hasFDerivAt, gradient, (toDual 𝕜 F).apply_symm_apply (fderiv 𝕜 f x)]
exact h.hasFDerivAt
theorem HasGradientAt.differentiableAt (h : HasGradientAt f f' x) :
DifferentiableAt 𝕜 f x :=
h.hasFDerivAt.differentiableAt
theorem DifferentiableWithinAt.hasGradientWithinAt (h : DifferentiableWithinAt 𝕜 f s x) :
HasGradientWithinAt f (gradientWithin f s x) s x := by
rw [hasGradientWithinAt_iff_hasFDerivWithinAt, gradientWithin,
(toDual 𝕜 F).apply_symm_apply (fderivWithin 𝕜 f s x)]
exact h.hasFDerivWithinAt
theorem HasGradientWithinAt.differentiableWithinAt (h : HasGradientWithinAt f f' s x) :
DifferentiableWithinAt 𝕜 f s x :=
h.hasFDerivWithinAt.differentiableWithinAt
@[simp]
theorem hasGradientWithinAt_univ : HasGradientWithinAt f f' univ x ↔ HasGradientAt f f' x := by
rw [hasGradientWithinAt_iff_hasFDerivWithinAt, hasGradientAt_iff_hasFDerivAt]
exact hasFDerivWithinAt_univ
theorem DifferentiableOn.hasGradientAt (h : DifferentiableOn 𝕜 f s) (hs : s ∈ 𝓝 x) :
HasGradientAt f (∇ f x) x :=
(h.hasFDerivAt hs).hasGradientAt
theorem HasGradientAt.gradient (h : HasGradientAt f f' x) : ∇ f x = f' :=
h.differentiableAt.hasGradientAt.unique h
theorem gradient_eq {f' : F → F} (h : ∀ x, HasGradientAt f (f' x) x) : ∇ f = f' :=
funext fun x => (h x).gradient
open Filter
section Const
variable (c : 𝕜) (s x L)
theorem hasGradientAtFilter_const : HasGradientAtFilter (fun _ => c) 0 x L := by
rw [HasGradientAtFilter, map_zero]; apply hasFDerivAtFilter_const c x L
theorem hasGradientWithinAt_const : HasGradientWithinAt (fun _ => c) 0 s x :=
hasGradientAtFilter_const _ _ _
theorem hasGradientAt_const : HasGradientAt (fun _ => c) 0 x :=
hasGradientAtFilter_const _ _ _
| Mathlib/Analysis/Calculus/Gradient/Basic.lean | 313 | 314 | theorem gradient_const : ∇ (fun _ => c) x = 0 := by |
rw [gradient, fderiv_const, Pi.zero_apply, map_zero]
| 0 |
import Mathlib.Algebra.Polynomial.AlgebraMap
import Mathlib.Algebra.Polynomial.BigOperators
import Mathlib.Algebra.Polynomial.Degree.Lemmas
import Mathlib.Algebra.Polynomial.Div
#align_import data.polynomial.ring_division from "leanprover-community/mathlib"@"8efcf8022aac8e01df8d302dcebdbc25d6a886c8"
noncomputable section
open Polynomial
open Finset
namespace Polynomial
universe u v w z
variable {R : Type u} {S : Type v} {T : Type w} {a b : R} {n : ℕ}
section NoZeroDivisors
variable [CommSemiring R] [NoZeroDivisors R] {p q : R[X]}
| Mathlib/Algebra/Polynomial/RingDivision.lean | 245 | 256 | theorem irreducible_of_monic (hp : p.Monic) (hp1 : p ≠ 1) :
Irreducible p ↔ ∀ f g : R[X], f.Monic → g.Monic → f * g = p → f = 1 ∨ g = 1 := by |
refine
⟨fun h f g hf hg hp => (h.2 f g hp.symm).imp hf.eq_one_of_isUnit hg.eq_one_of_isUnit, fun h =>
⟨hp1 ∘ hp.eq_one_of_isUnit, fun f g hfg =>
(h (g * C f.leadingCoeff) (f * C g.leadingCoeff) ?_ ?_ ?_).symm.imp
(isUnit_of_mul_eq_one f _)
(isUnit_of_mul_eq_one g _)⟩⟩
· rwa [Monic, leadingCoeff_mul, leadingCoeff_C, ← leadingCoeff_mul, mul_comm, ← hfg, ← Monic]
· rwa [Monic, leadingCoeff_mul, leadingCoeff_C, ← leadingCoeff_mul, ← hfg, ← Monic]
· rw [mul_mul_mul_comm, ← C_mul, ← leadingCoeff_mul, ← hfg, hp.leadingCoeff, C_1, mul_one,
mul_comm, ← hfg]
| 0 |
import Mathlib.Analysis.NormedSpace.AddTorsor
import Mathlib.LinearAlgebra.AffineSpace.Ordered
import Mathlib.Topology.ContinuousFunction.Basic
import Mathlib.Topology.GDelta
import Mathlib.Analysis.NormedSpace.FunctionSeries
import Mathlib.Analysis.SpecificLimits.Basic
#align_import topology.urysohns_lemma from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982"
variable {X : Type*} [TopologicalSpace X]
open Set Filter TopologicalSpace Topology Filter
open scoped Pointwise
namespace Urysohns
set_option linter.uppercaseLean3 false
structure CU {X : Type*} [TopologicalSpace X] (P : Set X → Prop) where
protected C : Set X
protected U : Set X
protected P_C : P C
protected closed_C : IsClosed C
protected open_U : IsOpen U
protected subset : C ⊆ U
protected hP : ∀ {c u : Set X}, IsClosed c → P c → IsOpen u → c ⊆ u →
∃ v, IsOpen v ∧ c ⊆ v ∧ closure v ⊆ u ∧ P (closure v)
#align urysohns.CU Urysohns.CU
namespace CU
variable {P : Set X → Prop}
@[simps C]
def left (c : CU P) : CU P where
C := c.C
U := (c.hP c.closed_C c.P_C c.open_U c.subset).choose
closed_C := c.closed_C
P_C := c.P_C
open_U := (c.hP c.closed_C c.P_C c.open_U c.subset).choose_spec.1
subset := (c.hP c.closed_C c.P_C c.open_U c.subset).choose_spec.2.1
hP := c.hP
#align urysohns.CU.left Urysohns.CU.left
@[simps U]
def right (c : CU P) : CU P where
C := closure (c.hP c.closed_C c.P_C c.open_U c.subset).choose
U := c.U
closed_C := isClosed_closure
P_C := (c.hP c.closed_C c.P_C c.open_U c.subset).choose_spec.2.2.2
open_U := c.open_U
subset := (c.hP c.closed_C c.P_C c.open_U c.subset).choose_spec.2.2.1
hP := c.hP
#align urysohns.CU.right Urysohns.CU.right
theorem left_U_subset_right_C (c : CU P) : c.left.U ⊆ c.right.C :=
subset_closure
#align urysohns.CU.left_U_subset_right_C Urysohns.CU.left_U_subset_right_C
theorem left_U_subset (c : CU P) : c.left.U ⊆ c.U :=
Subset.trans c.left_U_subset_right_C c.right.subset
#align urysohns.CU.left_U_subset Urysohns.CU.left_U_subset
theorem subset_right_C (c : CU P) : c.C ⊆ c.right.C :=
Subset.trans c.left.subset c.left_U_subset_right_C
#align urysohns.CU.subset_right_C Urysohns.CU.subset_right_C
noncomputable def approx : ℕ → CU P → X → ℝ
| 0, c, x => indicator c.Uᶜ 1 x
| n + 1, c, x => midpoint ℝ (approx n c.left x) (approx n c.right x)
#align urysohns.CU.approx Urysohns.CU.approx
theorem approx_of_mem_C (c : CU P) (n : ℕ) {x : X} (hx : x ∈ c.C) : c.approx n x = 0 := by
induction' n with n ihn generalizing c
· exact indicator_of_not_mem (fun (hU : x ∈ c.Uᶜ) => hU <| c.subset hx) _
· simp only [approx]
rw [ihn, ihn, midpoint_self]
exacts [c.subset_right_C hx, hx]
#align urysohns.CU.approx_of_mem_C Urysohns.CU.approx_of_mem_C
theorem approx_of_nmem_U (c : CU P) (n : ℕ) {x : X} (hx : x ∉ c.U) : c.approx n x = 1 := by
induction' n with n ihn generalizing c
· rw [← mem_compl_iff] at hx
exact indicator_of_mem hx _
· simp only [approx]
rw [ihn, ihn, midpoint_self]
exacts [hx, fun hU => hx <| c.left_U_subset hU]
#align urysohns.CU.approx_of_nmem_U Urysohns.CU.approx_of_nmem_U
| Mathlib/Topology/UrysohnsLemma.lean | 178 | 182 | theorem approx_nonneg (c : CU P) (n : ℕ) (x : X) : 0 ≤ c.approx n x := by |
induction' n with n ihn generalizing c
· exact indicator_nonneg (fun _ _ => zero_le_one) _
· simp only [approx, midpoint_eq_smul_add, invOf_eq_inv]
refine mul_nonneg (inv_nonneg.2 zero_le_two) (add_nonneg ?_ ?_) <;> apply ihn
| 0 |
import Mathlib.Analysis.Calculus.LocalExtr.Basic
import Mathlib.Topology.Algebra.Order.Rolle
#align_import analysis.calculus.local_extr from "leanprover-community/mathlib"@"3bce8d800a6f2b8f63fe1e588fd76a9ff4adcebe"
open Set Filter Topology
variable {f f' : ℝ → ℝ} {a b l : ℝ}
theorem exists_hasDerivAt_eq_zero (hab : a < b) (hfc : ContinuousOn f (Icc a b)) (hfI : f a = f b)
(hff' : ∀ x ∈ Ioo a b, HasDerivAt f (f' x) x) : ∃ c ∈ Ioo a b, f' c = 0 :=
let ⟨c, cmem, hc⟩ := exists_isLocalExtr_Ioo hab hfc hfI
⟨c, cmem, hc.hasDerivAt_eq_zero <| hff' c cmem⟩
#align exists_has_deriv_at_eq_zero exists_hasDerivAt_eq_zero
theorem exists_deriv_eq_zero (hab : a < b) (hfc : ContinuousOn f (Icc a b)) (hfI : f a = f b) :
∃ c ∈ Ioo a b, deriv f c = 0 :=
let ⟨c, cmem, hc⟩ := exists_isLocalExtr_Ioo hab hfc hfI
⟨c, cmem, hc.deriv_eq_zero⟩
#align exists_deriv_eq_zero exists_deriv_eq_zero
theorem exists_hasDerivAt_eq_zero' (hab : a < b) (hfa : Tendsto f (𝓝[>] a) (𝓝 l))
(hfb : Tendsto f (𝓝[<] b) (𝓝 l)) (hff' : ∀ x ∈ Ioo a b, HasDerivAt f (f' x) x) :
∃ c ∈ Ioo a b, f' c = 0 :=
let ⟨c, cmem, hc⟩ := exists_isLocalExtr_Ioo_of_tendsto hab
(fun x hx ↦ (hff' x hx).continuousAt.continuousWithinAt) hfa hfb
⟨c, cmem, hc.hasDerivAt_eq_zero <| hff' c cmem⟩
#align exists_has_deriv_at_eq_zero' exists_hasDerivAt_eq_zero'
| Mathlib/Analysis/Calculus/LocalExtr/Rolle.lean | 78 | 84 | theorem exists_deriv_eq_zero' (hab : a < b) (hfa : Tendsto f (𝓝[>] a) (𝓝 l))
(hfb : Tendsto f (𝓝[<] b) (𝓝 l)) : ∃ c ∈ Ioo a b, deriv f c = 0 := by |
by_cases h : ∀ x ∈ Ioo a b, DifferentiableAt ℝ f x
· exact exists_hasDerivAt_eq_zero' hab hfa hfb fun x hx => (h x hx).hasDerivAt
· obtain ⟨c, hc, hcdiff⟩ : ∃ x ∈ Ioo a b, ¬DifferentiableAt ℝ f x := by
push_neg at h; exact h
exact ⟨c, hc, deriv_zero_of_not_differentiableAt hcdiff⟩
| 0 |
import Mathlib.Tactic.Qify
import Mathlib.Data.ZMod.Basic
import Mathlib.NumberTheory.DiophantineApproximation
import Mathlib.NumberTheory.Zsqrtd.Basic
#align_import number_theory.pell from "leanprover-community/mathlib"@"7ad820c4997738e2f542f8a20f32911f52020e26"
namespace Pell
open Zsqrtd
theorem is_pell_solution_iff_mem_unitary {d : ℤ} {a : ℤ√d} :
a.re ^ 2 - d * a.im ^ 2 = 1 ↔ a ∈ unitary (ℤ√d) := by
rw [← norm_eq_one_iff_mem_unitary, norm_def, sq, sq, ← mul_assoc]
#align pell.is_pell_solution_iff_mem_unitary Pell.is_pell_solution_iff_mem_unitary
-- We use `solution₁ d` to allow for a more general structure `solution d m` that
-- encodes solutions to `x^2 - d*y^2 = m` to be added later.
def Solution₁ (d : ℤ) : Type :=
↥(unitary (ℤ√d))
#align pell.solution₁ Pell.Solution₁
namespace Solution₁
variable {d : ℤ}
-- Porting note(https://github.com/leanprover-community/mathlib4/issues/5020): manual deriving
instance instCommGroup : CommGroup (Solution₁ d) :=
inferInstanceAs (CommGroup (unitary (ℤ√d)))
#align pell.solution₁.comm_group Pell.Solution₁.instCommGroup
instance instHasDistribNeg : HasDistribNeg (Solution₁ d) :=
inferInstanceAs (HasDistribNeg (unitary (ℤ√d)))
#align pell.solution₁.has_distrib_neg Pell.Solution₁.instHasDistribNeg
instance instInhabited : Inhabited (Solution₁ d) :=
inferInstanceAs (Inhabited (unitary (ℤ√d)))
#align pell.solution₁.inhabited Pell.Solution₁.instInhabited
instance : Coe (Solution₁ d) (ℤ√d) where coe := Subtype.val
protected def x (a : Solution₁ d) : ℤ :=
(a : ℤ√d).re
#align pell.solution₁.x Pell.Solution₁.x
protected def y (a : Solution₁ d) : ℤ :=
(a : ℤ√d).im
#align pell.solution₁.y Pell.Solution₁.y
theorem prop (a : Solution₁ d) : a.x ^ 2 - d * a.y ^ 2 = 1 :=
is_pell_solution_iff_mem_unitary.mpr a.property
#align pell.solution₁.prop Pell.Solution₁.prop
theorem prop_x (a : Solution₁ d) : a.x ^ 2 = 1 + d * a.y ^ 2 := by rw [← a.prop]; ring
#align pell.solution₁.prop_x Pell.Solution₁.prop_x
theorem prop_y (a : Solution₁ d) : d * a.y ^ 2 = a.x ^ 2 - 1 := by rw [← a.prop]; ring
#align pell.solution₁.prop_y Pell.Solution₁.prop_y
@[ext]
theorem ext {a b : Solution₁ d} (hx : a.x = b.x) (hy : a.y = b.y) : a = b :=
Subtype.ext <| Zsqrtd.ext _ _ hx hy
#align pell.solution₁.ext Pell.Solution₁.ext
def mk (x y : ℤ) (prop : x ^ 2 - d * y ^ 2 = 1) : Solution₁ d where
val := ⟨x, y⟩
property := is_pell_solution_iff_mem_unitary.mp prop
#align pell.solution₁.mk Pell.Solution₁.mk
@[simp]
theorem x_mk (x y : ℤ) (prop : x ^ 2 - d * y ^ 2 = 1) : (mk x y prop).x = x :=
rfl
#align pell.solution₁.x_mk Pell.Solution₁.x_mk
@[simp]
theorem y_mk (x y : ℤ) (prop : x ^ 2 - d * y ^ 2 = 1) : (mk x y prop).y = y :=
rfl
#align pell.solution₁.y_mk Pell.Solution₁.y_mk
@[simp]
theorem coe_mk (x y : ℤ) (prop : x ^ 2 - d * y ^ 2 = 1) : (↑(mk x y prop) : ℤ√d) = ⟨x, y⟩ :=
Zsqrtd.ext _ _ (x_mk x y prop) (y_mk x y prop)
#align pell.solution₁.coe_mk Pell.Solution₁.coe_mk
@[simp]
theorem x_one : (1 : Solution₁ d).x = 1 :=
rfl
#align pell.solution₁.x_one Pell.Solution₁.x_one
@[simp]
theorem y_one : (1 : Solution₁ d).y = 0 :=
rfl
#align pell.solution₁.y_one Pell.Solution₁.y_one
@[simp]
theorem x_mul (a b : Solution₁ d) : (a * b).x = a.x * b.x + d * (a.y * b.y) := by
rw [← mul_assoc]
rfl
#align pell.solution₁.x_mul Pell.Solution₁.x_mul
@[simp]
theorem y_mul (a b : Solution₁ d) : (a * b).y = a.x * b.y + a.y * b.x :=
rfl
#align pell.solution₁.y_mul Pell.Solution₁.y_mul
@[simp]
theorem x_inv (a : Solution₁ d) : a⁻¹.x = a.x :=
rfl
#align pell.solution₁.x_inv Pell.Solution₁.x_inv
@[simp]
theorem y_inv (a : Solution₁ d) : a⁻¹.y = -a.y :=
rfl
#align pell.solution₁.y_inv Pell.Solution₁.y_inv
@[simp]
theorem x_neg (a : Solution₁ d) : (-a).x = -a.x :=
rfl
#align pell.solution₁.x_neg Pell.Solution₁.x_neg
@[simp]
theorem y_neg (a : Solution₁ d) : (-a).y = -a.y :=
rfl
#align pell.solution₁.y_neg Pell.Solution₁.y_neg
| Mathlib/NumberTheory/Pell.lean | 209 | 214 | theorem eq_zero_of_d_neg (h₀ : d < 0) (a : Solution₁ d) : a.x = 0 ∨ a.y = 0 := by |
have h := a.prop
contrapose! h
have h1 := sq_pos_of_ne_zero h.1
have h2 := sq_pos_of_ne_zero h.2
nlinarith
| 0 |
import Mathlib.Analysis.InnerProductSpace.Calculus
import Mathlib.Analysis.InnerProductSpace.Dual
import Mathlib.Analysis.InnerProductSpace.Adjoint
import Mathlib.Analysis.Calculus.LagrangeMultipliers
import Mathlib.LinearAlgebra.Eigenspace.Basic
#align_import analysis.inner_product_space.rayleigh from "leanprover-community/mathlib"@"6b0169218d01f2837d79ea2784882009a0da1aa1"
variable {𝕜 : Type*} [RCLike 𝕜]
variable {E : Type*} [NormedAddCommGroup E] [InnerProductSpace 𝕜 E]
local notation "⟪" x ", " y "⟫" => @inner 𝕜 _ _ x y
open scoped NNReal
open Module.End Metric
namespace ContinuousLinearMap
variable (T : E →L[𝕜] E)
noncomputable abbrev rayleighQuotient (x : E) := T.reApplyInnerSelf x / ‖(x : E)‖ ^ 2
theorem rayleigh_smul (x : E) {c : 𝕜} (hc : c ≠ 0) :
rayleighQuotient T (c • x) = rayleighQuotient T x := by
by_cases hx : x = 0
· simp [hx]
have : ‖c‖ ≠ 0 := by simp [hc]
have : ‖x‖ ≠ 0 := by simp [hx]
field_simp [norm_smul, T.reApplyInnerSelf_smul]
ring
#align continuous_linear_map.rayleigh_smul ContinuousLinearMap.rayleigh_smul
| Mathlib/Analysis/InnerProductSpace/Rayleigh.lean | 67 | 80 | theorem image_rayleigh_eq_image_rayleigh_sphere {r : ℝ} (hr : 0 < r) :
rayleighQuotient T '' {0}ᶜ = rayleighQuotient T '' sphere 0 r := by |
ext a
constructor
· rintro ⟨x, hx : x ≠ 0, hxT⟩
have : ‖x‖ ≠ 0 := by simp [hx]
let c : 𝕜 := ↑‖x‖⁻¹ * r
have : c ≠ 0 := by simp [c, hx, hr.ne']
refine ⟨c • x, ?_, ?_⟩
· field_simp [c, norm_smul, abs_of_pos hr]
· rw [T.rayleigh_smul x this]
exact hxT
· rintro ⟨x, hx, hxT⟩
exact ⟨x, ne_zero_of_mem_sphere hr.ne' ⟨x, hx⟩, hxT⟩
| 0 |
import Mathlib.Analysis.SpecialFunctions.Integrals
import Mathlib.MeasureTheory.Integral.PeakFunction
#align_import analysis.special_functions.trigonometric.euler_sine_prod from "leanprover-community/mathlib"@"2c1d8ca2812b64f88992a5294ea3dba144755cd1"
open scoped Real Topology
open Real Set Filter intervalIntegral MeasureTheory.MeasureSpace
namespace EulerSine
section IntegralRecursion
variable {z : ℂ} {n : ℕ}
theorem antideriv_cos_comp_const_mul (hz : z ≠ 0) (x : ℝ) :
HasDerivAt (fun y : ℝ => Complex.sin (2 * z * y) / (2 * z)) (Complex.cos (2 * z * x)) x := by
have a : HasDerivAt (fun y : ℂ => y * (2 * z)) _ x := hasDerivAt_mul_const _
have b : HasDerivAt (fun y : ℂ => Complex.sin (y * (2 * z))) _ x :=
HasDerivAt.comp (x : ℂ) (Complex.hasDerivAt_sin (x * (2 * z))) a
have c := b.comp_ofReal.div_const (2 * z)
field_simp at c; simp only [fun y => mul_comm y (2 * z)] at c
exact c
#align euler_sine.antideriv_cos_comp_const_mul EulerSine.antideriv_cos_comp_const_mul
| Mathlib/Analysis/SpecialFunctions/Trigonometric/EulerSineProd.lean | 49 | 56 | theorem antideriv_sin_comp_const_mul (hz : z ≠ 0) (x : ℝ) :
HasDerivAt (fun y : ℝ => -Complex.cos (2 * z * y) / (2 * z)) (Complex.sin (2 * z * x)) x := by |
have a : HasDerivAt (fun y : ℂ => y * (2 * z)) _ x := hasDerivAt_mul_const _
have b : HasDerivAt (fun y : ℂ => Complex.cos (y * (2 * z))) _ x :=
HasDerivAt.comp (x : ℂ) (Complex.hasDerivAt_cos (x * (2 * z))) a
have c := (b.comp_ofReal.div_const (2 * z)).neg
field_simp at c; simp only [fun y => mul_comm y (2 * z)] at c
exact c
| 0 |
import Mathlib.CategoryTheory.Limits.Preserves.Finite
import Mathlib.CategoryTheory.Sites.Canonical
import Mathlib.CategoryTheory.Sites.Coherent.Basic
import Mathlib.CategoryTheory.Sites.Preserves
universe v u w
namespace CategoryTheory
open Limits
variable {C : Type u} [Category.{v} C]
variable [FinitaryPreExtensive C]
class Presieve.Extensive {X : C} (R : Presieve X) : Prop where
arrows_nonempty_isColimit : ∃ (α : Type) (_ : Finite α) (Z : α → C) (π : (a : α) → (Z a ⟶ X)),
R = Presieve.ofArrows Z π ∧ Nonempty (IsColimit (Cofan.mk X π))
instance {X : C} (S : Presieve X) [S.Extensive] : S.hasPullbacks where
has_pullbacks := by
obtain ⟨_, _, _, _, rfl, ⟨hc⟩⟩ := Presieve.Extensive.arrows_nonempty_isColimit (R := S)
intro _ _ _ _ _ hg
cases hg
apply FinitaryPreExtensive.hasPullbacks_of_is_coproduct hc
open Presieve Opposite
| Mathlib/CategoryTheory/Sites/Coherent/ExtensiveSheaves.lean | 52 | 58 | theorem isSheafFor_extensive_of_preservesFiniteProducts {X : C} (S : Presieve X) [S.Extensive]
(F : Cᵒᵖ ⥤ Type w) [PreservesFiniteProducts F] : S.IsSheafFor F := by |
obtain ⟨α, _, Z, π, rfl, ⟨hc⟩⟩ := Extensive.arrows_nonempty_isColimit (R := S)
have : (ofArrows Z (Cofan.mk X π).inj).hasPullbacks :=
(inferInstance : (ofArrows Z π).hasPullbacks)
cases nonempty_fintype α
exact isSheafFor_of_preservesProduct _ _ hc
| 0 |
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
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]
set_option linter.uppercaseLean3 false in
#align NonemptyFinLinOrd.mono_iff_injective NonemptyFinLinOrd.mono_iff_injective
-- Porting note: added to ease the following proof
lemma forget_map_apply {A B : NonemptyFinLinOrd.{u}} (f : A ⟶ B) (a : A) :
(forget NonemptyFinLinOrd).map f a = (f : OrderHom A B).toFun a := rfl
| Mathlib/Order/Category/NonemptyFinLinOrd.lean | 171 | 209 | theorem epi_iff_surjective {A B : NonemptyFinLinOrd.{u}} (f : A ⟶ B) :
Epi f ↔ Function.Surjective f := by |
constructor
· intro
dsimp only [Function.Surjective]
by_contra! hf'
rcases hf' with ⟨m, hm⟩
let Y := NonemptyFinLinOrd.of (ULift (Fin 2))
let p₁ : B ⟶ Y :=
⟨fun b => if b < m then ULift.up 0 else ULift.up 1, fun x₁ x₂ h => by
simp only
split_ifs with h₁ h₂ h₂
any_goals apply Fin.zero_le
· exfalso
exact h₁ (lt_of_le_of_lt h h₂)
· rfl⟩
let p₂ : B ⟶ Y :=
⟨fun b => if b ≤ m then ULift.up 0 else ULift.up 1, fun x₁ x₂ h => by
simp only
split_ifs with h₁ h₂ h₂
any_goals apply Fin.zero_le
· exfalso
exact h₁ (h.trans h₂)
· rfl⟩
have h : p₁ m = p₂ m := by
congr
rw [← cancel_epi f]
ext a
simp only [coe_of, comp_apply]
change ite _ _ _ = ite _ _ _
split_ifs with h₁ h₂ h₂
any_goals rfl
· exfalso
exact h₂ (le_of_lt h₁)
· exfalso
exact hm a (eq_of_le_of_not_lt h₂ h₁)
simp [Y, DFunLike.coe] at h
· intro h
exact ConcreteCategory.epi_of_surjective f h
| 0 |
import Mathlib.ModelTheory.Satisfiability
#align_import model_theory.types from "leanprover-community/mathlib"@"98bd247d933fb581ff37244a5998bd33d81dd46d"
set_option linter.uppercaseLean3 false
universe u v w w'
open Cardinal Set
open scoped Classical
open Cardinal FirstOrder
namespace FirstOrder
namespace Language
namespace Theory
variable {L : Language.{u, v}} (T : L.Theory) (α : Type w)
structure CompleteType where
toTheory : L[[α]].Theory
subset' : (L.lhomWithConstants α).onTheory T ⊆ toTheory
isMaximal' : toTheory.IsMaximal
#align first_order.language.Theory.complete_type FirstOrder.Language.Theory.CompleteType
#align first_order.language.Theory.complete_type.to_Theory FirstOrder.Language.Theory.CompleteType.toTheory
#align first_order.language.Theory.complete_type.subset' FirstOrder.Language.Theory.CompleteType.subset'
#align first_order.language.Theory.complete_type.is_maximal' FirstOrder.Language.Theory.CompleteType.isMaximal'
variable {T α}
namespace CompleteType
attribute [coe] CompleteType.toTheory
instance Sentence.instSetLike : SetLike (T.CompleteType α) (L[[α]].Sentence) :=
⟨fun p => p.toTheory, fun p q h => by
cases p
cases q
congr ⟩
#align first_order.language.Theory.complete_type.sentence.set_like FirstOrder.Language.Theory.CompleteType.Sentence.instSetLike
theorem isMaximal (p : T.CompleteType α) : IsMaximal (p : L[[α]].Theory) :=
p.isMaximal'
#align first_order.language.Theory.complete_type.is_maximal FirstOrder.Language.Theory.CompleteType.isMaximal
theorem subset (p : T.CompleteType α) : (L.lhomWithConstants α).onTheory T ⊆ (p : L[[α]].Theory) :=
p.subset'
#align first_order.language.Theory.complete_type.subset FirstOrder.Language.Theory.CompleteType.subset
theorem mem_or_not_mem (p : T.CompleteType α) (φ : L[[α]].Sentence) : φ ∈ p ∨ φ.not ∈ p :=
p.isMaximal.mem_or_not_mem φ
#align first_order.language.Theory.complete_type.mem_or_not_mem FirstOrder.Language.Theory.CompleteType.mem_or_not_mem
theorem mem_of_models (p : T.CompleteType α) {φ : L[[α]].Sentence}
(h : (L.lhomWithConstants α).onTheory T ⊨ᵇ φ) : φ ∈ p :=
(p.mem_or_not_mem φ).resolve_right fun con =>
((models_iff_not_satisfiable _).1 h)
(p.isMaximal.1.mono (union_subset p.subset (singleton_subset_iff.2 con)))
#align first_order.language.Theory.complete_type.mem_of_models FirstOrder.Language.Theory.CompleteType.mem_of_models
theorem not_mem_iff (p : T.CompleteType α) (φ : L[[α]].Sentence) : φ.not ∈ p ↔ ¬φ ∈ p :=
⟨fun hf ht => by
have h : ¬IsSatisfiable ({φ, φ.not} : L[[α]].Theory) := by
rintro ⟨@⟨_, _, h, _⟩⟩
simp only [model_iff, mem_insert_iff, mem_singleton_iff, forall_eq_or_imp, forall_eq] at h
exact h.2 h.1
refine h (p.isMaximal.1.mono ?_)
rw [insert_subset_iff, singleton_subset_iff]
exact ⟨ht, hf⟩, (p.mem_or_not_mem φ).resolve_left⟩
#align first_order.language.Theory.complete_type.not_mem_iff FirstOrder.Language.Theory.CompleteType.not_mem_iff
@[simp]
theorem compl_setOf_mem {φ : L[[α]].Sentence} :
{ p : T.CompleteType α | φ ∈ p }ᶜ = { p : T.CompleteType α | φ.not ∈ p } :=
ext fun _ => (not_mem_iff _ _).symm
#align first_order.language.Theory.complete_type.compl_set_of_mem FirstOrder.Language.Theory.CompleteType.compl_setOf_mem
| Mathlib/ModelTheory/Types.lean | 115 | 126 | theorem setOf_subset_eq_empty_iff (S : L[[α]].Theory) :
{ p : T.CompleteType α | S ⊆ ↑p } = ∅ ↔
¬((L.lhomWithConstants α).onTheory T ∪ S).IsSatisfiable := by |
rw [iff_not_comm, ← not_nonempty_iff_eq_empty, Classical.not_not, Set.Nonempty]
refine
⟨fun h =>
⟨⟨L[[α]].completeTheory h.some, (subset_union_left (t := S)).trans completeTheory.subset,
completeTheory.isMaximal (L[[α]]) h.some⟩,
(((L.lhomWithConstants α).onTheory T).subset_union_right).trans completeTheory.subset⟩,
?_⟩
rintro ⟨p, hp⟩
exact p.isMaximal.1.mono (union_subset p.subset hp)
| 0 |
import Mathlib.Data.W.Basic
#align_import data.pfunctor.univariate.basic from "leanprover-community/mathlib"@"8631e2d5ea77f6c13054d9151d82b83069680cb1"
-- "W", "Idx"
set_option linter.uppercaseLean3 false
universe u v v₁ v₂ v₃
@[pp_with_univ]
structure PFunctor where
A : Type u
B : A → Type u
#align pfunctor PFunctor
namespace PFunctor
instance : Inhabited PFunctor :=
⟨⟨default, default⟩⟩
variable (P : PFunctor.{u}) {α : Type v₁} {β : Type v₂} {γ : Type v₃}
@[coe]
def Obj (α : Type v) :=
Σ x : P.A, P.B x → α
#align pfunctor.obj PFunctor.Obj
instance : CoeFun PFunctor.{u} (fun _ => Type v → Type (max u v)) where
coe := Obj
def map (f : α → β) : P α → P β :=
fun ⟨a, g⟩ => ⟨a, f ∘ g⟩
#align pfunctor.map PFunctor.map
instance Obj.inhabited [Inhabited P.A] [Inhabited α] : Inhabited (P α) :=
⟨⟨default, default⟩⟩
#align pfunctor.obj.inhabited PFunctor.Obj.inhabited
instance : Functor.{v, max u v} P.Obj where map := @map P
@[simp]
theorem map_eq_map {α β : Type v} (f : α → β) (x : P α) : f <$> x = P.map f x :=
rfl
@[simp]
protected theorem map_eq (f : α → β) (a : P.A) (g : P.B a → α) :
P.map f ⟨a, g⟩ = ⟨a, f ∘ g⟩ :=
rfl
#align pfunctor.map_eq PFunctor.map_eq
@[simp]
protected theorem id_map : ∀ x : P α, P.map id x = x := fun ⟨_, _⟩ => rfl
#align pfunctor.id_map PFunctor.id_map
@[simp]
protected theorem map_map (f : α → β) (g : β → γ) :
∀ x : P α, P.map g (P.map f x) = P.map (g ∘ f) x := fun ⟨_, _⟩ => rfl
#align pfunctor.comp_map PFunctor.map_map
instance : LawfulFunctor.{v, max u v} P.Obj where
map_const := rfl
id_map x := P.id_map x
comp_map f g x := P.map_map f g x |>.symm
def W :=
WType P.B
#align pfunctor.W PFunctor.W
-- Porting note(#5171): this linter isn't ported yet.
-- attribute [nolint has_nonempty_instance] W
variable {P}
def W.head : W P → P.A
| ⟨a, _f⟩ => a
#align pfunctor.W.head PFunctor.W.head
def W.children : ∀ x : W P, P.B (W.head x) → W P
| ⟨_a, f⟩ => f
#align pfunctor.W.children PFunctor.W.children
def W.dest : W P → P (W P)
| ⟨a, f⟩ => ⟨a, f⟩
#align pfunctor.W.dest PFunctor.W.dest
def W.mk : P (W P) → W P
| ⟨a, f⟩ => ⟨a, f⟩
#align pfunctor.W.mk PFunctor.W.mk
@[simp]
theorem W.dest_mk (p : P (W P)) : W.dest (W.mk p) = p := by cases p; rfl
#align pfunctor.W.dest_mk PFunctor.W.dest_mk
@[simp]
| Mathlib/Data/PFunctor/Univariate/Basic.lean | 129 | 129 | theorem W.mk_dest (p : W P) : W.mk (W.dest p) = p := by | cases p; rfl
| 0 |
import Mathlib.Algebra.Group.Subgroup.Basic
import Mathlib.CategoryTheory.Groupoid.VertexGroup
import Mathlib.CategoryTheory.Groupoid.Basic
import Mathlib.CategoryTheory.Groupoid
import Mathlib.Data.Set.Lattice
import Mathlib.Order.GaloisConnection
#align_import category_theory.groupoid.subgroupoid from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a"
namespace CategoryTheory
open Set Groupoid
universe u v
variable {C : Type u} [Groupoid C]
@[ext]
structure Subgroupoid (C : Type u) [Groupoid C] where
arrows : ∀ c d : C, Set (c ⟶ d)
protected inv : ∀ {c d} {p : c ⟶ d}, p ∈ arrows c d → Groupoid.inv p ∈ arrows d c
protected mul : ∀ {c d e} {p}, p ∈ arrows c d → ∀ {q}, q ∈ arrows d e → p ≫ q ∈ arrows c e
#align category_theory.subgroupoid CategoryTheory.Subgroupoid
namespace Subgroupoid
variable (S : Subgroupoid C)
theorem inv_mem_iff {c d : C} (f : c ⟶ d) :
Groupoid.inv f ∈ S.arrows d c ↔ f ∈ S.arrows c d := by
constructor
· intro h
simpa only [inv_eq_inv, IsIso.inv_inv] using S.inv h
· apply S.inv
#align category_theory.subgroupoid.inv_mem_iff CategoryTheory.Subgroupoid.inv_mem_iff
theorem mul_mem_cancel_left {c d e : C} {f : c ⟶ d} {g : d ⟶ e} (hf : f ∈ S.arrows c d) :
f ≫ g ∈ S.arrows c e ↔ g ∈ S.arrows d e := by
constructor
· rintro h
suffices Groupoid.inv f ≫ f ≫ g ∈ S.arrows d e by
simpa only [inv_eq_inv, IsIso.inv_hom_id_assoc] using this
apply S.mul (S.inv hf) h
· apply S.mul hf
#align category_theory.subgroupoid.mul_mem_cancel_left CategoryTheory.Subgroupoid.mul_mem_cancel_left
theorem mul_mem_cancel_right {c d e : C} {f : c ⟶ d} {g : d ⟶ e} (hg : g ∈ S.arrows d e) :
f ≫ g ∈ S.arrows c e ↔ f ∈ S.arrows c d := by
constructor
· rintro h
suffices (f ≫ g) ≫ Groupoid.inv g ∈ S.arrows c d by
simpa only [inv_eq_inv, IsIso.hom_inv_id, Category.comp_id, Category.assoc] using this
apply S.mul h (S.inv hg)
· exact fun hf => S.mul hf hg
#align category_theory.subgroupoid.mul_mem_cancel_right CategoryTheory.Subgroupoid.mul_mem_cancel_right
def objs : Set C :=
{c : C | (S.arrows c c).Nonempty}
#align category_theory.subgroupoid.objs CategoryTheory.Subgroupoid.objs
theorem mem_objs_of_src {c d : C} {f : c ⟶ d} (h : f ∈ S.arrows c d) : c ∈ S.objs :=
⟨f ≫ Groupoid.inv f, S.mul h (S.inv h)⟩
#align category_theory.subgroupoid.mem_objs_of_src CategoryTheory.Subgroupoid.mem_objs_of_src
theorem mem_objs_of_tgt {c d : C} {f : c ⟶ d} (h : f ∈ S.arrows c d) : d ∈ S.objs :=
⟨Groupoid.inv f ≫ f, S.mul (S.inv h) h⟩
#align category_theory.subgroupoid.mem_objs_of_tgt CategoryTheory.Subgroupoid.mem_objs_of_tgt
| Mathlib/CategoryTheory/Groupoid/Subgroupoid.lean | 123 | 126 | theorem id_mem_of_nonempty_isotropy (c : C) : c ∈ objs S → 𝟙 c ∈ S.arrows c c := by |
rintro ⟨γ, hγ⟩
convert S.mul hγ (S.inv hγ)
simp only [inv_eq_inv, IsIso.hom_inv_id]
| 0 |
import Mathlib.Algebra.Group.Submonoid.Pointwise
#align_import group_theory.submonoid.inverses from "leanprover-community/mathlib"@"59694bd07f0a39c5beccba34bd9f413a160782bf"
variable {M : Type*}
namespace Submonoid
@[to_additive]
noncomputable instance [Monoid M] : Group (IsUnit.submonoid M) :=
{ inferInstanceAs (Monoid (IsUnit.submonoid M)) with
inv := fun x ↦ ⟨x.prop.unit⁻¹.val, x.prop.unit⁻¹.isUnit⟩
mul_left_inv := fun x ↦
Subtype.ext ((Units.val_mul x.prop.unit⁻¹ _).trans x.prop.unit.inv_val) }
@[to_additive]
noncomputable instance [CommMonoid M] : CommGroup (IsUnit.submonoid M) :=
{ inferInstanceAs (Group (IsUnit.submonoid M)) with
mul_comm := fun a b ↦ by convert mul_comm a b }
@[to_additive]
theorem IsUnit.Submonoid.coe_inv [Monoid M] (x : IsUnit.submonoid M) :
↑x⁻¹ = (↑x.prop.unit⁻¹ : M) :=
rfl
#align submonoid.is_unit.submonoid.coe_inv Submonoid.IsUnit.Submonoid.coe_inv
#align add_submonoid.is_unit.submonoid.coe_neg AddSubmonoid.IsUnit.Submonoid.coe_neg
section Monoid
variable [Monoid M] (S : Submonoid M)
@[to_additive
"`S.leftNeg` is the additive submonoid containing all the left additive inverses of `S`."]
def leftInv : Submonoid M where
carrier := { x : M | ∃ y : S, x * y = 1 }
one_mem' := ⟨1, mul_one 1⟩
mul_mem' := fun {a} _b ⟨a', ha⟩ ⟨b', hb⟩ ↦
⟨b' * a', by simp only [coe_mul, ← mul_assoc, mul_assoc a, hb, mul_one, ha]⟩
#align submonoid.left_inv Submonoid.leftInv
#align add_submonoid.left_neg AddSubmonoid.leftNeg
@[to_additive]
theorem leftInv_leftInv_le : S.leftInv.leftInv ≤ S := by
rintro x ⟨⟨y, z, h₁⟩, h₂ : x * y = 1⟩
convert z.prop
rw [← mul_one x, ← h₁, ← mul_assoc, h₂, one_mul]
#align submonoid.left_inv_left_inv_le Submonoid.leftInv_leftInv_le
#align add_submonoid.left_neg_left_neg_le AddSubmonoid.leftNeg_leftNeg_le
@[to_additive]
theorem unit_mem_leftInv (x : Mˣ) (hx : (x : M) ∈ S) : ((x⁻¹ : _) : M) ∈ S.leftInv :=
⟨⟨x, hx⟩, x.inv_val⟩
#align submonoid.unit_mem_left_inv Submonoid.unit_mem_leftInv
#align add_submonoid.add_unit_mem_left_neg AddSubmonoid.addUnit_mem_leftNeg
@[to_additive]
| Mathlib/GroupTheory/Submonoid/Inverses.lean | 87 | 94 | theorem leftInv_leftInv_eq (hS : S ≤ IsUnit.submonoid M) : S.leftInv.leftInv = S := by |
refine le_antisymm S.leftInv_leftInv_le ?_
intro x hx
have : x = ((hS hx).unit⁻¹⁻¹ : Mˣ) := by
rw [inv_inv (hS hx).unit]
rfl
rw [this]
exact S.leftInv.unit_mem_leftInv _ (S.unit_mem_leftInv _ hx)
| 0 |
import Mathlib.Algebra.Polynomial.Eval
import Mathlib.LinearAlgebra.Dimension.Constructions
#align_import algebra.linear_recurrence from "leanprover-community/mathlib"@"039a089d2a4b93c761b234f3e5f5aeb752bac60f"
noncomputable section
open Finset
open Polynomial
structure LinearRecurrence (α : Type*) [CommSemiring α] where
order : ℕ
coeffs : Fin order → α
#align linear_recurrence LinearRecurrence
instance (α : Type*) [CommSemiring α] : Inhabited (LinearRecurrence α) :=
⟨⟨0, default⟩⟩
namespace LinearRecurrence
section CommSemiring
variable {α : Type*} [CommSemiring α] (E : LinearRecurrence α)
def IsSolution (u : ℕ → α) :=
∀ n, u (n + E.order) = ∑ i, E.coeffs i * u (n + i)
#align linear_recurrence.is_solution LinearRecurrence.IsSolution
def mkSol (init : Fin E.order → α) : ℕ → α
| n =>
if h : n < E.order then init ⟨n, h⟩
else
∑ k : Fin E.order,
have _ : n - E.order + k < n := by
rw [add_comm, ← add_tsub_assoc_of_le (not_lt.mp h), tsub_lt_iff_left]
· exact add_lt_add_right k.is_lt n
· convert add_le_add (zero_le (k : ℕ)) (not_lt.mp h)
simp only [zero_add]
E.coeffs k * mkSol init (n - E.order + k)
#align linear_recurrence.mk_sol LinearRecurrence.mkSol
theorem is_sol_mkSol (init : Fin E.order → α) : E.IsSolution (E.mkSol init) := by
intro n
rw [mkSol]
simp
#align linear_recurrence.is_sol_mk_sol LinearRecurrence.is_sol_mkSol
theorem mkSol_eq_init (init : Fin E.order → α) : ∀ n : Fin E.order, E.mkSol init n = init n := by
intro n
rw [mkSol]
simp only [n.is_lt, dif_pos, Fin.mk_val, Fin.eta]
#align linear_recurrence.mk_sol_eq_init LinearRecurrence.mkSol_eq_init
theorem eq_mk_of_is_sol_of_eq_init {u : ℕ → α} {init : Fin E.order → α} (h : E.IsSolution u)
(heq : ∀ n : Fin E.order, u n = init n) : ∀ n, u n = E.mkSol init n := by
intro n
rw [mkSol]
split_ifs with h'
· exact mod_cast heq ⟨n, h'⟩
simp only
rw [← tsub_add_cancel_of_le (le_of_not_lt h'), h (n - E.order)]
congr with k
have : n - E.order + k < n := by
rw [add_comm, ← add_tsub_assoc_of_le (not_lt.mp h'), tsub_lt_iff_left]
· exact add_lt_add_right k.is_lt n
· convert add_le_add (zero_le (k : ℕ)) (not_lt.mp h')
simp only [zero_add]
rw [eq_mk_of_is_sol_of_eq_init h heq (n - E.order + k)]
simp
#align linear_recurrence.eq_mk_of_is_sol_of_eq_init LinearRecurrence.eq_mk_of_is_sol_of_eq_init
theorem eq_mk_of_is_sol_of_eq_init' {u : ℕ → α} {init : Fin E.order → α} (h : E.IsSolution u)
(heq : ∀ n : Fin E.order, u n = init n) : u = E.mkSol init :=
funext (E.eq_mk_of_is_sol_of_eq_init h heq)
#align linear_recurrence.eq_mk_of_is_sol_of_eq_init' LinearRecurrence.eq_mk_of_is_sol_of_eq_init'
def solSpace : Submodule α (ℕ → α) where
carrier := { u | E.IsSolution u }
zero_mem' n := by simp
add_mem' {u v} hu hv n := by simp [mul_add, sum_add_distrib, hu n, hv n]
smul_mem' a u hu n := by simp [hu n, mul_sum]; congr; ext; ac_rfl
#align linear_recurrence.sol_space LinearRecurrence.solSpace
theorem is_sol_iff_mem_solSpace (u : ℕ → α) : E.IsSolution u ↔ u ∈ E.solSpace :=
Iff.rfl
#align linear_recurrence.is_sol_iff_mem_sol_space LinearRecurrence.is_sol_iff_mem_solSpace
def toInit : E.solSpace ≃ₗ[α] Fin E.order → α where
toFun u x := (u : ℕ → α) x
map_add' u v := by
ext
simp
map_smul' a u := by
ext
simp
invFun u := ⟨E.mkSol u, E.is_sol_mkSol u⟩
left_inv u := by ext n; symm; apply E.eq_mk_of_is_sol_of_eq_init u.2; intro k; rfl
right_inv u := Function.funext_iff.mpr fun n ↦ E.mkSol_eq_init u n
#align linear_recurrence.to_init LinearRecurrence.toInit
| Mathlib/Algebra/LinearRecurrence.lean | 156 | 166 | theorem sol_eq_of_eq_init (u v : ℕ → α) (hu : E.IsSolution u) (hv : E.IsSolution v) :
u = v ↔ Set.EqOn u v ↑(range E.order) := by |
refine Iff.intro (fun h x _ ↦ h ▸ rfl) ?_
intro h
set u' : ↥E.solSpace := ⟨u, hu⟩
set v' : ↥E.solSpace := ⟨v, hv⟩
change u'.val = v'.val
suffices h' : u' = v' from h' ▸ rfl
rw [← E.toInit.toEquiv.apply_eq_iff_eq, LinearEquiv.coe_toEquiv]
ext x
exact mod_cast h (mem_range.mpr x.2)
| 0 |
import Mathlib.Algebra.Lie.Nilpotent
import Mathlib.Algebra.Lie.Normalizer
#align_import algebra.lie.cartan_subalgebra from "leanprover-community/mathlib"@"938fead7abdc0cbbca8eba7a1052865a169dc102"
universe u v w w₁ w₂
variable {R : Type u} {L : Type v}
variable [CommRing R] [LieRing L] [LieAlgebra R L] (H : LieSubalgebra R L)
def LieSubmodule.IsUcsLimit {M : Type*} [AddCommGroup M] [Module R M] [LieRingModule L M]
[LieModule R L M] (N : LieSubmodule R L M) : Prop :=
∃ k, ∀ l, k ≤ l → (⊥ : LieSubmodule R L M).ucs l = N
#align lie_submodule.is_ucs_limit LieSubmodule.IsUcsLimit
namespace LieSubalgebra
class IsCartanSubalgebra : Prop where
nilpotent : LieAlgebra.IsNilpotent R H
self_normalizing : H.normalizer = H
#align lie_subalgebra.is_cartan_subalgebra LieSubalgebra.IsCartanSubalgebra
instance [H.IsCartanSubalgebra] : LieAlgebra.IsNilpotent R H :=
IsCartanSubalgebra.nilpotent
@[simp]
theorem normalizer_eq_self_of_isCartanSubalgebra (H : LieSubalgebra R L) [H.IsCartanSubalgebra] :
H.toLieSubmodule.normalizer = H.toLieSubmodule := by
rw [← LieSubmodule.coe_toSubmodule_eq_iff, coe_normalizer_eq_normalizer,
IsCartanSubalgebra.self_normalizing, coe_toLieSubmodule]
#align lie_subalgebra.normalizer_eq_self_of_is_cartan_subalgebra LieSubalgebra.normalizer_eq_self_of_isCartanSubalgebra
@[simp]
theorem ucs_eq_self_of_isCartanSubalgebra (H : LieSubalgebra R L) [H.IsCartanSubalgebra] (k : ℕ) :
H.toLieSubmodule.ucs k = H.toLieSubmodule := by
induction' k with k ih
· simp
· simp [ih]
#align lie_subalgebra.ucs_eq_self_of_is_cartan_subalgebra LieSubalgebra.ucs_eq_self_of_isCartanSubalgebra
| Mathlib/Algebra/Lie/CartanSubalgebra.lean | 72 | 94 | theorem isCartanSubalgebra_iff_isUcsLimit : H.IsCartanSubalgebra ↔ H.toLieSubmodule.IsUcsLimit := by |
constructor
· intro h
have h₁ : LieAlgebra.IsNilpotent R H := by infer_instance
obtain ⟨k, hk⟩ := H.toLieSubmodule.isNilpotent_iff_exists_self_le_ucs.mp h₁
replace hk : H.toLieSubmodule = LieSubmodule.ucs k ⊥ :=
le_antisymm hk
(LieSubmodule.ucs_le_of_normalizer_eq_self H.normalizer_eq_self_of_isCartanSubalgebra k)
refine ⟨k, fun l hl => ?_⟩
rw [← Nat.sub_add_cancel hl, LieSubmodule.ucs_add, ← hk,
LieSubalgebra.ucs_eq_self_of_isCartanSubalgebra]
· rintro ⟨k, hk⟩
exact
{ nilpotent := by
dsimp only [LieAlgebra.IsNilpotent]
erw [H.toLieSubmodule.isNilpotent_iff_exists_lcs_eq_bot]
use k
rw [_root_.eq_bot_iff, LieSubmodule.lcs_le_iff, hk k (le_refl k)]
self_normalizing := by
have hk' := hk (k + 1) k.le_succ
rw [LieSubmodule.ucs_succ, hk k (le_refl k)] at hk'
rw [← LieSubalgebra.coe_to_submodule_eq_iff, ← LieSubalgebra.coe_normalizer_eq_normalizer,
hk', LieSubalgebra.coe_toLieSubmodule] }
| 0 |
import Mathlib.Algebra.Polynomial.Taylor
import Mathlib.RingTheory.Ideal.LocalRing
import Mathlib.RingTheory.AdicCompletion.Basic
#align_import ring_theory.henselian from "leanprover-community/mathlib"@"d1accf4f9cddb3666c6e8e4da0ac2d19c4ed73f0"
noncomputable section
universe u v
open Polynomial LocalRing Polynomial Function List
theorem isLocalRingHom_of_le_jacobson_bot {R : Type*} [CommRing R] (I : Ideal R)
(h : I ≤ Ideal.jacobson ⊥) : IsLocalRingHom (Ideal.Quotient.mk I) := by
constructor
intro a h
have : IsUnit (Ideal.Quotient.mk (Ideal.jacobson ⊥) a) := by
rw [isUnit_iff_exists_inv] at *
obtain ⟨b, hb⟩ := h
obtain ⟨b, rfl⟩ := Ideal.Quotient.mk_surjective b
use Ideal.Quotient.mk _ b
rw [← (Ideal.Quotient.mk _).map_one, ← (Ideal.Quotient.mk _).map_mul, Ideal.Quotient.eq] at hb ⊢
exact h hb
obtain ⟨⟨x, y, h1, h2⟩, rfl : x = _⟩ := this
obtain ⟨y, rfl⟩ := Ideal.Quotient.mk_surjective y
rw [← (Ideal.Quotient.mk _).map_mul, ← (Ideal.Quotient.mk _).map_one, Ideal.Quotient.eq,
Ideal.mem_jacobson_bot] at h1 h2
specialize h1 1
simp? at h1 says simp only [mul_one, sub_add_cancel, IsUnit.mul_iff] at h1
exact h1.1
#align is_local_ring_hom_of_le_jacobson_bot isLocalRingHom_of_le_jacobson_bot
class HenselianRing (R : Type*) [CommRing R] (I : Ideal R) : Prop where
jac : I ≤ Ideal.jacobson ⊥
is_henselian :
∀ (f : R[X]) (_ : f.Monic) (a₀ : R) (_ : f.eval a₀ ∈ I)
(_ : IsUnit (Ideal.Quotient.mk I (f.derivative.eval a₀))), ∃ a : R, f.IsRoot a ∧ a - a₀ ∈ I
#align henselian_ring HenselianRing
class HenselianLocalRing (R : Type*) [CommRing R] extends LocalRing R : Prop where
is_henselian :
∀ (f : R[X]) (_ : f.Monic) (a₀ : R) (_ : f.eval a₀ ∈ maximalIdeal R)
(_ : IsUnit (f.derivative.eval a₀)), ∃ a : R, f.IsRoot a ∧ a - a₀ ∈ maximalIdeal R
#align henselian_local_ring HenselianLocalRing
-- see Note [lower instance priority]
instance (priority := 100) Field.henselian (K : Type*) [Field K] : HenselianLocalRing K where
is_henselian f _ a₀ h₁ _ := by
simp only [(maximalIdeal K).eq_bot_of_prime, Ideal.mem_bot] at h₁ ⊢
exact ⟨a₀, h₁, sub_self _⟩
#align field.henselian Field.henselian
| Mathlib/RingTheory/Henselian.lean | 121 | 155 | theorem HenselianLocalRing.TFAE (R : Type u) [CommRing R] [LocalRing R] :
TFAE
[HenselianLocalRing R,
∀ f : R[X], f.Monic → ∀ a₀ : ResidueField R, aeval a₀ f = 0 →
aeval a₀ (derivative f) ≠ 0 → ∃ a : R, f.IsRoot a ∧ residue R a = a₀,
∀ {K : Type u} [Field K],
∀ (φ : R →+* K), Surjective φ → ∀ f : R[X], f.Monic → ∀ a₀ : K,
f.eval₂ φ a₀ = 0 → f.derivative.eval₂ φ a₀ ≠ 0 → ∃ a : R, f.IsRoot a ∧ φ a = a₀] := by |
tfae_have 3 → 2
· intro H
exact H (residue R) Ideal.Quotient.mk_surjective
tfae_have 2 → 1
· intro H
constructor
intro f hf a₀ h₁ h₂
specialize H f hf (residue R a₀)
have aux := flip mem_nonunits_iff.mp h₂
simp only [aeval_def, ResidueField.algebraMap_eq, eval₂_at_apply, ←
Ideal.Quotient.eq_zero_iff_mem, ← LocalRing.mem_maximalIdeal] at H h₁ aux
obtain ⟨a, ha₁, ha₂⟩ := H h₁ aux
refine ⟨a, ha₁, ?_⟩
rw [← Ideal.Quotient.eq_zero_iff_mem]
rwa [← sub_eq_zero, ← RingHom.map_sub] at ha₂
tfae_have 1 → 3
· intro hR K _K φ hφ f hf a₀ h₁ h₂
obtain ⟨a₀, rfl⟩ := hφ a₀
have H := HenselianLocalRing.is_henselian f hf a₀
simp only [← ker_eq_maximalIdeal φ hφ, eval₂_at_apply, RingHom.mem_ker φ] at H h₁ h₂
obtain ⟨a, ha₁, ha₂⟩ := H h₁ (by
contrapose! h₂
rwa [← mem_nonunits_iff, ← LocalRing.mem_maximalIdeal, ← LocalRing.ker_eq_maximalIdeal φ hφ,
RingHom.mem_ker] at h₂)
refine ⟨a, ha₁, ?_⟩
rwa [φ.map_sub, sub_eq_zero] at ha₂
tfae_finish
| 0 |
import Mathlib.Data.Nat.Choose.Central
import Mathlib.Data.Nat.Factorization.Basic
import Mathlib.Data.Nat.Multiplicity
#align_import data.nat.choose.factorization from "leanprover-community/mathlib"@"dc9db541168768af03fe228703e758e649afdbfc"
namespace Nat
variable {p n k : ℕ}
theorem factorization_choose_le_log : (choose n k).factorization p ≤ log p n := by
by_cases h : (choose n k).factorization p = 0
· simp [h]
have hp : p.Prime := Not.imp_symm (choose n k).factorization_eq_zero_of_non_prime h
have hkn : k ≤ n := by
refine le_of_not_lt fun hnk => h ?_
simp [choose_eq_zero_of_lt hnk]
rw [factorization_def _ hp, @padicValNat_def _ ⟨hp⟩ _ (choose_pos hkn)]
simp only [hp.multiplicity_choose hkn (lt_add_one _), PartENat.get_natCast]
exact (Finset.card_filter_le _ _).trans (le_of_eq (Nat.card_Ico _ _))
#align nat.factorization_choose_le_log Nat.factorization_choose_le_log
theorem pow_factorization_choose_le (hn : 0 < n) : p ^ (choose n k).factorization p ≤ n :=
pow_le_of_le_log hn.ne' factorization_choose_le_log
#align nat.pow_factorization_choose_le Nat.pow_factorization_choose_le
| Mathlib/Data/Nat/Choose/Factorization.lean | 55 | 58 | theorem factorization_choose_le_one (p_large : n < p ^ 2) : (choose n k).factorization p ≤ 1 := by |
apply factorization_choose_le_log.trans
rcases eq_or_ne n 0 with (rfl | hn0); · simp
exact Nat.lt_succ_iff.1 (log_lt_of_lt_pow hn0 p_large)
| 0 |
import Mathlib.Analysis.NormedSpace.OperatorNorm.Bilinear
import Mathlib.Analysis.NormedSpace.OperatorNorm.NNNorm
suppress_compilation
open Bornology Metric Set Real
open Filter hiding map_smul
open scoped Classical NNReal Topology Uniformity
-- the `ₗ` subscript variables are for special cases about linear (as opposed to semilinear) maps
variable {𝕜 𝕜₂ 𝕜₃ E Eₗ F Fₗ G Gₗ 𝓕 : Type*}
variable [NormedAddCommGroup E] [NormedAddCommGroup F] [NormedAddCommGroup G]
[NormedAddCommGroup Fₗ]
variable [NontriviallyNormedField 𝕜] [NontriviallyNormedField 𝕜₂] [NontriviallyNormedField 𝕜₃]
[NormedSpace 𝕜 E] [NormedSpace 𝕜₂ F] [NormedSpace 𝕜₃ G] [NormedSpace 𝕜 Fₗ] (c : 𝕜)
{σ₁₂ : 𝕜 →+* 𝕜₂} {σ₂₃ : 𝕜₂ →+* 𝕜₃} (f g : E →SL[σ₁₂] F) (x y z : E)
namespace ContinuousLinearMap
section UniformlyExtend
variable [CompleteSpace F] (e : E →L[𝕜] Fₗ) (h_dense : DenseRange e)
section
variable (h_e : UniformInducing e)
def extend : Fₗ →SL[σ₁₂] F :=
-- extension of `f` is continuous
have cont := (uniformContinuous_uniformly_extend h_e h_dense f.uniformContinuous).continuous
-- extension of `f` agrees with `f` on the domain of the embedding `e`
have eq := uniformly_extend_of_ind h_e h_dense f.uniformContinuous
{ toFun := (h_e.denseInducing h_dense).extend f
map_add' := by
refine h_dense.induction_on₂ ?_ ?_
· exact isClosed_eq (cont.comp continuous_add)
((cont.comp continuous_fst).add (cont.comp continuous_snd))
· intro x y
simp only [eq, ← e.map_add]
exact f.map_add _ _
map_smul' := fun k => by
refine fun b => h_dense.induction_on b ?_ ?_
· exact isClosed_eq (cont.comp (continuous_const_smul _))
((continuous_const_smul _).comp cont)
· intro x
rw [← map_smul]
simp only [eq]
exact ContinuousLinearMap.map_smulₛₗ _ _ _
cont }
#align continuous_linear_map.extend ContinuousLinearMap.extend
-- Porting note: previously `(h_e.denseInducing h_dense)` was inferred.
@[simp]
theorem extend_eq (x : E) : extend f e h_dense h_e (e x) = f x :=
DenseInducing.extend_eq (h_e.denseInducing h_dense) f.cont _
#align continuous_linear_map.extend_eq ContinuousLinearMap.extend_eq
theorem extend_unique (g : Fₗ →SL[σ₁₂] F) (H : g.comp e = f) : extend f e h_dense h_e = g :=
ContinuousLinearMap.coeFn_injective <|
uniformly_extend_unique h_e h_dense (ContinuousLinearMap.ext_iff.1 H) g.continuous
#align continuous_linear_map.extend_unique ContinuousLinearMap.extend_unique
@[simp]
theorem extend_zero : extend (0 : E →SL[σ₁₂] F) e h_dense h_e = 0 :=
extend_unique _ _ _ _ _ (zero_comp _)
#align continuous_linear_map.extend_zero ContinuousLinearMap.extend_zero
end
section
variable {N : ℝ≥0} (h_e : ∀ x, ‖x‖ ≤ N * ‖e x‖) [RingHomIsometric σ₁₂]
| Mathlib/Analysis/NormedSpace/OperatorNorm/Completeness.lean | 246 | 263 | theorem opNorm_extend_le :
‖f.extend e h_dense (uniformEmbedding_of_bound _ h_e).toUniformInducing‖ ≤ N * ‖f‖ := by |
-- Add `opNorm_le_of_dense`?
refine opNorm_le_bound _ ?_ (isClosed_property h_dense (isClosed_le ?_ ?_) fun x ↦ ?_)
· cases le_total 0 N with
| inl hN => exact mul_nonneg hN (norm_nonneg _)
| inr hN =>
have : Unique E := ⟨⟨0⟩, fun x ↦ norm_le_zero_iff.mp <|
(h_e x).trans (mul_nonpos_of_nonpos_of_nonneg hN (norm_nonneg _))⟩
obtain rfl : f = 0 := Subsingleton.elim ..
simp
· exact (cont _).norm
· exact continuous_const.mul continuous_norm
· rw [extend_eq]
calc
‖f x‖ ≤ ‖f‖ * ‖x‖ := le_opNorm _ _
_ ≤ ‖f‖ * (N * ‖e x‖) := mul_le_mul_of_nonneg_left (h_e x) (norm_nonneg _)
_ ≤ N * ‖f‖ * ‖e x‖ := by rw [mul_comm ↑N ‖f‖, mul_assoc]
| 0 |
import Mathlib.Analysis.Analytic.Basic
import Mathlib.Combinatorics.Enumerative.Composition
#align_import analysis.analytic.composition from "leanprover-community/mathlib"@"ce11c3c2a285bbe6937e26d9792fda4e51f3fe1a"
noncomputable section
variable {𝕜 : Type*} {E F G H : Type*}
open Filter List
open scoped Topology Classical NNReal ENNReal
section Topological
variable [CommRing 𝕜] [AddCommGroup E] [AddCommGroup F] [AddCommGroup G]
variable [Module 𝕜 E] [Module 𝕜 F] [Module 𝕜 G]
variable [TopologicalSpace E] [TopologicalSpace F] [TopologicalSpace G]
namespace FormalMultilinearSeries
variable [TopologicalAddGroup E] [ContinuousConstSMul 𝕜 E]
variable [TopologicalAddGroup F] [ContinuousConstSMul 𝕜 F]
variable [TopologicalAddGroup G] [ContinuousConstSMul 𝕜 G]
def applyComposition (p : FormalMultilinearSeries 𝕜 E F) {n : ℕ} (c : Composition n) :
(Fin n → E) → Fin c.length → F := fun v i => p (c.blocksFun i) (v ∘ c.embedding i)
#align formal_multilinear_series.apply_composition FormalMultilinearSeries.applyComposition
theorem applyComposition_ones (p : FormalMultilinearSeries 𝕜 E F) (n : ℕ) :
p.applyComposition (Composition.ones n) = fun v i =>
p 1 fun _ => v (Fin.castLE (Composition.length_le _) i) := by
funext v i
apply p.congr (Composition.ones_blocksFun _ _)
intro j hjn hj1
obtain rfl : j = 0 := by omega
refine congr_arg v ?_
rw [Fin.ext_iff, Fin.coe_castLE, Composition.ones_embedding, Fin.val_mk]
#align formal_multilinear_series.apply_composition_ones FormalMultilinearSeries.applyComposition_ones
| Mathlib/Analysis/Analytic/Composition.lean | 117 | 127 | theorem applyComposition_single (p : FormalMultilinearSeries 𝕜 E F) {n : ℕ} (hn : 0 < n)
(v : Fin n → E) : p.applyComposition (Composition.single n hn) v = fun _j => p n v := by |
ext j
refine p.congr (by simp) fun i hi1 hi2 => ?_
dsimp
congr 1
convert Composition.single_embedding hn ⟨i, hi2⟩ using 1
cases' j with j_val j_property
have : j_val = 0 := le_bot_iff.1 (Nat.lt_succ_iff.1 j_property)
congr!
simp
| 0 |
import Mathlib.LinearAlgebra.Quotient
import Mathlib.RingTheory.Ideal.Operations
namespace Submodule
open Pointwise
variable {R M M' F G : Type*} [CommRing R] [AddCommGroup M] [Module R M]
variable {N N₁ N₂ P P₁ P₂ : Submodule R M}
def colon (N P : Submodule R M) : Ideal R :=
annihilator (P.map N.mkQ)
#align submodule.colon Submodule.colon
theorem mem_colon {r} : r ∈ N.colon P ↔ ∀ p ∈ P, r • p ∈ N :=
mem_annihilator.trans
⟨fun H p hp => (Quotient.mk_eq_zero N).1 (H (Quotient.mk p) (mem_map_of_mem hp)),
fun H _ ⟨p, hp, hpm⟩ => hpm ▸ ((Quotient.mk_eq_zero N).2 <| H p hp)⟩
#align submodule.mem_colon Submodule.mem_colon
theorem mem_colon' {r} : r ∈ N.colon P ↔ P ≤ comap (r • (LinearMap.id : M →ₗ[R] M)) N :=
mem_colon
#align submodule.mem_colon' Submodule.mem_colon'
@[simp]
theorem colon_top {I : Ideal R} : I.colon ⊤ = I := by
simp_rw [SetLike.ext_iff, mem_colon, smul_eq_mul]
exact fun x ↦ ⟨fun h ↦ mul_one x ▸ h 1 trivial, fun h _ _ ↦ I.mul_mem_right _ h⟩
@[simp]
theorem colon_bot : colon ⊥ N = N.annihilator := by
simp_rw [SetLike.ext_iff, mem_colon, mem_annihilator, mem_bot, forall_const]
theorem colon_mono (hn : N₁ ≤ N₂) (hp : P₁ ≤ P₂) : N₁.colon P₂ ≤ N₂.colon P₁ := fun _ hrnp =>
mem_colon.2 fun p₁ hp₁ => hn <| mem_colon.1 hrnp p₁ <| hp hp₁
#align submodule.colon_mono Submodule.colon_mono
theorem iInf_colon_iSup (ι₁ : Sort*) (f : ι₁ → Submodule R M) (ι₂ : Sort*)
(g : ι₂ → Submodule R M) : (⨅ i, f i).colon (⨆ j, g j) = ⨅ (i) (j), (f i).colon (g j) :=
le_antisymm (le_iInf fun _ => le_iInf fun _ => colon_mono (iInf_le _ _) (le_iSup _ _)) fun _ H =>
mem_colon'.2 <|
iSup_le fun j =>
map_le_iff_le_comap.1 <|
le_iInf fun i =>
map_le_iff_le_comap.2 <|
mem_colon'.1 <|
have := (mem_iInf _).1 H i
have := (mem_iInf _).1 this j
this
#align submodule.infi_colon_supr Submodule.iInf_colon_iSup
@[simp]
| Mathlib/RingTheory/Ideal/Colon.lean | 67 | 72 | theorem mem_colon_singleton {N : Submodule R M} {x : M} {r : R} :
r ∈ N.colon (Submodule.span R {x}) ↔ r • x ∈ N :=
calc
r ∈ N.colon (Submodule.span R {x}) ↔ ∀ a : R, r • a • x ∈ N := by |
simp [Submodule.mem_colon, Submodule.mem_span_singleton]
_ ↔ r • x ∈ N := by simp_rw [fun (a : R) ↦ smul_comm r a x]; exact SetLike.forall_smul_mem_iff
| 0 |
import Mathlib.MeasureTheory.Integral.Lebesgue
open Set hiding restrict restrict_apply
open Filter ENNReal NNReal MeasureTheory.Measure
namespace MeasureTheory
variable {α : Type*} {m0 : MeasurableSpace α} {μ : Measure α}
noncomputable
def Measure.withDensity {m : MeasurableSpace α} (μ : Measure α) (f : α → ℝ≥0∞) : Measure α :=
Measure.ofMeasurable (fun s _ => ∫⁻ a in s, f a ∂μ) (by simp) fun s hs hd =>
lintegral_iUnion hs hd _
#align measure_theory.measure.with_density MeasureTheory.Measure.withDensity
@[simp]
theorem withDensity_apply (f : α → ℝ≥0∞) {s : Set α} (hs : MeasurableSet s) :
μ.withDensity f s = ∫⁻ a in s, f a ∂μ :=
Measure.ofMeasurable_apply s hs
#align measure_theory.with_density_apply MeasureTheory.withDensity_apply
theorem withDensity_apply_le (f : α → ℝ≥0∞) (s : Set α) :
∫⁻ a in s, f a ∂μ ≤ μ.withDensity f s := by
let t := toMeasurable (μ.withDensity f) s
calc
∫⁻ a in s, f a ∂μ ≤ ∫⁻ a in t, f a ∂μ :=
lintegral_mono_set (subset_toMeasurable (withDensity μ f) s)
_ = μ.withDensity f t :=
(withDensity_apply f (measurableSet_toMeasurable (withDensity μ f) s)).symm
_ = μ.withDensity f s := measure_toMeasurable s
theorem withDensity_apply' [SFinite μ] (f : α → ℝ≥0∞) (s : Set α) :
μ.withDensity f s = ∫⁻ a in s, f a ∂μ := by
apply le_antisymm ?_ (withDensity_apply_le f s)
let t := toMeasurable μ s
calc
μ.withDensity f s ≤ μ.withDensity f t := measure_mono (subset_toMeasurable μ s)
_ = ∫⁻ a in t, f a ∂μ := withDensity_apply f (measurableSet_toMeasurable μ s)
_ = ∫⁻ a in s, f a ∂μ := by congr 1; exact restrict_toMeasurable_of_sFinite s
@[simp]
lemma withDensity_zero_left (f : α → ℝ≥0∞) : (0 : Measure α).withDensity f = 0 := by
ext s hs
rw [withDensity_apply _ hs]
simp
theorem withDensity_congr_ae {f g : α → ℝ≥0∞} (h : f =ᵐ[μ] g) :
μ.withDensity f = μ.withDensity g := by
refine Measure.ext fun s hs => ?_
rw [withDensity_apply _ hs, withDensity_apply _ hs]
exact lintegral_congr_ae (ae_restrict_of_ae h)
#align measure_theory.with_density_congr_ae MeasureTheory.withDensity_congr_ae
lemma withDensity_mono {f g : α → ℝ≥0∞} (hfg : f ≤ᵐ[μ] g) :
μ.withDensity f ≤ μ.withDensity g := by
refine le_iff.2 fun s hs ↦ ?_
rw [withDensity_apply _ hs, withDensity_apply _ hs]
refine set_lintegral_mono_ae' hs ?_
filter_upwards [hfg] with x h_le using fun _ ↦ h_le
theorem withDensity_add_left {f : α → ℝ≥0∞} (hf : Measurable f) (g : α → ℝ≥0∞) :
μ.withDensity (f + g) = μ.withDensity f + μ.withDensity g := by
refine Measure.ext fun s hs => ?_
rw [withDensity_apply _ hs, Measure.add_apply, withDensity_apply _ hs, withDensity_apply _ hs,
← lintegral_add_left hf]
simp only [Pi.add_apply]
#align measure_theory.with_density_add_left MeasureTheory.withDensity_add_left
theorem withDensity_add_right (f : α → ℝ≥0∞) {g : α → ℝ≥0∞} (hg : Measurable g) :
μ.withDensity (f + g) = μ.withDensity f + μ.withDensity g := by
simpa only [add_comm] using withDensity_add_left hg f
#align measure_theory.with_density_add_right MeasureTheory.withDensity_add_right
theorem withDensity_add_measure {m : MeasurableSpace α} (μ ν : Measure α) (f : α → ℝ≥0∞) :
(μ + ν).withDensity f = μ.withDensity f + ν.withDensity f := by
ext1 s hs
simp only [withDensity_apply f hs, restrict_add, lintegral_add_measure, Measure.add_apply]
#align measure_theory.with_density_add_measure MeasureTheory.withDensity_add_measure
theorem withDensity_sum {ι : Type*} {m : MeasurableSpace α} (μ : ι → Measure α) (f : α → ℝ≥0∞) :
(sum μ).withDensity f = sum fun n => (μ n).withDensity f := by
ext1 s hs
simp_rw [sum_apply _ hs, withDensity_apply f hs, restrict_sum μ hs, lintegral_sum_measure]
#align measure_theory.with_density_sum MeasureTheory.withDensity_sum
theorem withDensity_smul (r : ℝ≥0∞) {f : α → ℝ≥0∞} (hf : Measurable f) :
μ.withDensity (r • f) = r • μ.withDensity f := by
refine Measure.ext fun s hs => ?_
rw [withDensity_apply _ hs, Measure.coe_smul, Pi.smul_apply, withDensity_apply _ hs,
smul_eq_mul, ← lintegral_const_mul r hf]
simp only [Pi.smul_apply, smul_eq_mul]
#align measure_theory.with_density_smul MeasureTheory.withDensity_smul
theorem withDensity_smul' (r : ℝ≥0∞) (f : α → ℝ≥0∞) (hr : r ≠ ∞) :
μ.withDensity (r • f) = r • μ.withDensity f := by
refine Measure.ext fun s hs => ?_
rw [withDensity_apply _ hs, Measure.coe_smul, Pi.smul_apply, withDensity_apply _ hs,
smul_eq_mul, ← lintegral_const_mul' r f hr]
simp only [Pi.smul_apply, smul_eq_mul]
#align measure_theory.with_density_smul' MeasureTheory.withDensity_smul'
| Mathlib/MeasureTheory/Measure/WithDensity.lean | 138 | 142 | theorem withDensity_smul_measure (r : ℝ≥0∞) (f : α → ℝ≥0∞) :
(r • μ).withDensity f = r • μ.withDensity f := by |
ext s hs
rw [withDensity_apply _ hs, Measure.coe_smul, Pi.smul_apply, withDensity_apply _ hs,
smul_eq_mul, set_lintegral_smul_measure]
| 0 |
import Mathlib.Probability.Independence.Basic
import Mathlib.Probability.Independence.Conditional
#align_import probability.independence.zero_one from "leanprover-community/mathlib"@"2f8347015b12b0864dfaf366ec4909eb70c78740"
open MeasureTheory MeasurableSpace
open scoped MeasureTheory ENNReal
namespace ProbabilityTheory
variable {α Ω ι : Type*} {_mα : MeasurableSpace α} {s : ι → MeasurableSpace Ω}
{m m0 : MeasurableSpace Ω} {κ : kernel α Ω} {μα : Measure α} {μ : Measure Ω}
| Mathlib/Probability/Independence/ZeroOne.lean | 33 | 44 | theorem kernel.measure_eq_zero_or_one_or_top_of_indepSet_self {t : Set Ω}
(h_indep : kernel.IndepSet t t κ μα) :
∀ᵐ a ∂μα, κ a t = 0 ∨ κ a t = 1 ∨ κ a t = ∞ := by |
specialize h_indep t t (measurableSet_generateFrom (Set.mem_singleton t))
(measurableSet_generateFrom (Set.mem_singleton t))
filter_upwards [h_indep] with a ha
by_cases h0 : κ a t = 0
· exact Or.inl h0
by_cases h_top : κ a t = ∞
· exact Or.inr (Or.inr h_top)
rw [← one_mul (κ a (t ∩ t)), Set.inter_self, ENNReal.mul_eq_mul_right h0 h_top] at ha
exact Or.inr (Or.inl ha.symm)
| 0 |
import Mathlib.Probability.Kernel.MeasurableIntegral
#align_import probability.kernel.composition from "leanprover-community/mathlib"@"3b92d54a05ee592aa2c6181a4e76b1bb7cc45d0b"
open MeasureTheory
open scoped ENNReal
namespace ProbabilityTheory
namespace kernel
variable {α β ι : Type*} {mα : MeasurableSpace α} {mβ : MeasurableSpace β}
section CompositionProduct
variable {γ : Type*} {mγ : MeasurableSpace γ} {s : Set (β × γ)}
noncomputable def compProdFun (κ : kernel α β) (η : kernel (α × β) γ) (a : α) (s : Set (β × γ)) :
ℝ≥0∞ :=
∫⁻ b, η (a, b) {c | (b, c) ∈ s} ∂κ a
#align probability_theory.kernel.comp_prod_fun ProbabilityTheory.kernel.compProdFun
theorem compProdFun_empty (κ : kernel α β) (η : kernel (α × β) γ) (a : α) :
compProdFun κ η a ∅ = 0 := by
simp only [compProdFun, Set.mem_empty_iff_false, Set.setOf_false, measure_empty,
MeasureTheory.lintegral_const, zero_mul]
#align probability_theory.kernel.comp_prod_fun_empty ProbabilityTheory.kernel.compProdFun_empty
| Mathlib/Probability/Kernel/Composition.lean | 99 | 128 | theorem compProdFun_iUnion (κ : kernel α β) (η : kernel (α × β) γ) [IsSFiniteKernel η] (a : α)
(f : ℕ → Set (β × γ)) (hf_meas : ∀ i, MeasurableSet (f i))
(hf_disj : Pairwise (Disjoint on f)) :
compProdFun κ η a (⋃ i, f i) = ∑' i, compProdFun κ η a (f i) := by |
have h_Union :
(fun b => η (a, b) {c : γ | (b, c) ∈ ⋃ i, f i}) = fun b =>
η (a, b) (⋃ i, {c : γ | (b, c) ∈ f i}) := by
ext1 b
congr with c
simp only [Set.mem_iUnion, Set.iSup_eq_iUnion, Set.mem_setOf_eq]
rw [compProdFun, h_Union]
have h_tsum :
(fun b => η (a, b) (⋃ i, {c : γ | (b, c) ∈ f i})) = fun b =>
∑' i, η (a, b) {c : γ | (b, c) ∈ f i} := by
ext1 b
rw [measure_iUnion]
· intro i j hij s hsi hsj c hcs
have hbci : {(b, c)} ⊆ f i := by rw [Set.singleton_subset_iff]; exact hsi hcs
have hbcj : {(b, c)} ⊆ f j := by rw [Set.singleton_subset_iff]; exact hsj hcs
simpa only [Set.bot_eq_empty, Set.le_eq_subset, Set.singleton_subset_iff,
Set.mem_empty_iff_false] using hf_disj hij hbci hbcj
· -- Porting note: behavior of `@` changed relative to lean 3, was
-- exact fun i => (@measurable_prod_mk_left β γ _ _ b) _ (hf_meas i)
exact fun i => (@measurable_prod_mk_left β γ _ _ b) (hf_meas i)
rw [h_tsum, lintegral_tsum]
· rfl
· intro i
have hm : MeasurableSet {p : (α × β) × γ | (p.1.2, p.2) ∈ f i} :=
measurable_fst.snd.prod_mk measurable_snd (hf_meas i)
exact ((measurable_kernel_prod_mk_left hm).comp measurable_prod_mk_left).aemeasurable
| 0 |
import Mathlib.Analysis.Convex.Between
import Mathlib.Analysis.Convex.Jensen
import Mathlib.Analysis.Convex.Topology
import Mathlib.Analysis.Normed.Group.Pointwise
import Mathlib.Analysis.NormedSpace.AddTorsor
#align_import analysis.convex.normed from "leanprover-community/mathlib"@"a63928c34ec358b5edcda2bf7513c50052a5230f"
variable {ι : Type*} {E P : Type*}
open Metric Set
open scoped Convex
variable [SeminormedAddCommGroup E] [NormedSpace ℝ E] [PseudoMetricSpace P] [NormedAddTorsor E P]
variable {s t : Set E}
theorem convexOn_norm (hs : Convex ℝ s) : ConvexOn ℝ s norm :=
⟨hs, fun x _ y _ a b ha hb _ =>
calc
‖a • x + b • y‖ ≤ ‖a • x‖ + ‖b • y‖ := norm_add_le _ _
_ = a * ‖x‖ + b * ‖y‖ := by
rw [norm_smul, norm_smul, Real.norm_of_nonneg ha, Real.norm_of_nonneg hb]⟩
#align convex_on_norm convexOn_norm
theorem convexOn_univ_norm : ConvexOn ℝ univ (norm : E → ℝ) :=
convexOn_norm convex_univ
#align convex_on_univ_norm convexOn_univ_norm
theorem convexOn_dist (z : E) (hs : Convex ℝ s) : ConvexOn ℝ s fun z' => dist z' z := by
simpa [dist_eq_norm, preimage_preimage] using
(convexOn_norm (hs.translate (-z))).comp_affineMap (AffineMap.id ℝ E - AffineMap.const ℝ E z)
#align convex_on_dist convexOn_dist
theorem convexOn_univ_dist (z : E) : ConvexOn ℝ univ fun z' => dist z' z :=
convexOn_dist z convex_univ
#align convex_on_univ_dist convexOn_univ_dist
theorem convex_ball (a : E) (r : ℝ) : Convex ℝ (Metric.ball a r) := by
simpa only [Metric.ball, sep_univ] using (convexOn_univ_dist a).convex_lt r
#align convex_ball convex_ball
theorem convex_closedBall (a : E) (r : ℝ) : Convex ℝ (Metric.closedBall a r) := by
simpa only [Metric.closedBall, sep_univ] using (convexOn_univ_dist a).convex_le r
#align convex_closed_ball convex_closedBall
theorem Convex.thickening (hs : Convex ℝ s) (δ : ℝ) : Convex ℝ (thickening δ s) := by
rw [← add_ball_zero]
exact hs.add (convex_ball 0 _)
#align convex.thickening Convex.thickening
theorem Convex.cthickening (hs : Convex ℝ s) (δ : ℝ) : Convex ℝ (cthickening δ s) := by
obtain hδ | hδ := le_total 0 δ
· rw [cthickening_eq_iInter_thickening hδ]
exact convex_iInter₂ fun _ _ => hs.thickening _
· rw [cthickening_of_nonpos hδ]
exact hs.closure
#align convex.cthickening Convex.cthickening
theorem convexHull_exists_dist_ge {s : Set E} {x : E} (hx : x ∈ convexHull ℝ s) (y : E) :
∃ x' ∈ s, dist x y ≤ dist x' y :=
(convexOn_dist y (convex_convexHull ℝ _)).exists_ge_of_mem_convexHull hx
#align convex_hull_exists_dist_ge convexHull_exists_dist_ge
theorem convexHull_exists_dist_ge2 {s t : Set E} {x y : E} (hx : x ∈ convexHull ℝ s)
(hy : y ∈ convexHull ℝ t) : ∃ x' ∈ s, ∃ y' ∈ t, dist x y ≤ dist x' y' := by
rcases convexHull_exists_dist_ge hx y with ⟨x', hx', Hx'⟩
rcases convexHull_exists_dist_ge hy x' with ⟨y', hy', Hy'⟩
use x', hx', y', hy'
exact le_trans Hx' (dist_comm y x' ▸ dist_comm y' x' ▸ Hy')
#align convex_hull_exists_dist_ge2 convexHull_exists_dist_ge2
@[simp]
| Mathlib/Analysis/Convex/Normed.lean | 102 | 108 | theorem convexHull_ediam (s : Set E) : EMetric.diam (convexHull ℝ s) = EMetric.diam s := by |
refine (EMetric.diam_le fun x hx y hy => ?_).antisymm (EMetric.diam_mono <| subset_convexHull ℝ s)
rcases convexHull_exists_dist_ge2 hx hy with ⟨x', hx', y', hy', H⟩
rw [edist_dist]
apply le_trans (ENNReal.ofReal_le_ofReal H)
rw [← edist_dist]
exact EMetric.edist_le_diam_of_mem hx' hy'
| 0 |
import Mathlib.Algebra.Order.Ring.Nat
import Mathlib.Combinatorics.SetFamily.Compression.Down
import Mathlib.Order.UpperLower.Basic
import Mathlib.Data.Fintype.Powerset
#align_import combinatorics.set_family.harris_kleitman from "leanprover-community/mathlib"@"b363547b3113d350d053abdf2884e9850a56b205"
open Finset
variable {α : Type*} [DecidableEq α] {𝒜 ℬ : Finset (Finset α)} {s : Finset α} {a : α}
theorem IsLowerSet.nonMemberSubfamily (h : IsLowerSet (𝒜 : Set (Finset α))) :
IsLowerSet (𝒜.nonMemberSubfamily a : Set (Finset α)) := fun s t hts => by
simp_rw [mem_coe, mem_nonMemberSubfamily]
exact And.imp (h hts) (mt <| @hts _)
#align is_lower_set.non_member_subfamily IsLowerSet.nonMemberSubfamily
theorem IsLowerSet.memberSubfamily (h : IsLowerSet (𝒜 : Set (Finset α))) :
IsLowerSet (𝒜.memberSubfamily a : Set (Finset α)) := by
rintro s t hts
simp_rw [mem_coe, mem_memberSubfamily]
exact And.imp (h <| insert_subset_insert _ hts) (mt <| @hts _)
#align is_lower_set.member_subfamily IsLowerSet.memberSubfamily
theorem IsLowerSet.memberSubfamily_subset_nonMemberSubfamily (h : IsLowerSet (𝒜 : Set (Finset α))) :
𝒜.memberSubfamily a ⊆ 𝒜.nonMemberSubfamily a := fun s => by
rw [mem_memberSubfamily, mem_nonMemberSubfamily]
exact And.imp_left (h <| subset_insert _ _)
#align is_lower_set.member_subfamily_subset_non_member_subfamily IsLowerSet.memberSubfamily_subset_nonMemberSubfamily
theorem IsLowerSet.le_card_inter_finset' (h𝒜 : IsLowerSet (𝒜 : Set (Finset α)))
(hℬ : IsLowerSet (ℬ : Set (Finset α))) (h𝒜s : ∀ t ∈ 𝒜, t ⊆ s) (hℬs : ∀ t ∈ ℬ, t ⊆ s) :
𝒜.card * ℬ.card ≤ 2 ^ s.card * (𝒜 ∩ ℬ).card := by
induction' s using Finset.induction with a s hs ih generalizing 𝒜 ℬ
· simp_rw [subset_empty, ← subset_singleton_iff', subset_singleton_iff] at h𝒜s hℬs
obtain rfl | rfl := h𝒜s
· simp only [card_empty, zero_mul, empty_inter, mul_zero, le_refl]
obtain rfl | rfl := hℬs
· simp only [card_empty, inter_empty, mul_zero, zero_mul, le_refl]
· simp only [card_empty, pow_zero, inter_singleton_of_mem, mem_singleton, card_singleton,
le_refl]
rw [card_insert_of_not_mem hs, ← card_memberSubfamily_add_card_nonMemberSubfamily a 𝒜, ←
card_memberSubfamily_add_card_nonMemberSubfamily a ℬ, add_mul, mul_add, mul_add,
add_comm (_ * _), add_add_add_comm]
refine
(add_le_add_right
(mul_add_mul_le_mul_add_mul
(card_le_card h𝒜.memberSubfamily_subset_nonMemberSubfamily) <|
card_le_card hℬ.memberSubfamily_subset_nonMemberSubfamily)
_).trans
?_
rw [← two_mul, pow_succ', mul_assoc]
have h₀ : ∀ 𝒞 : Finset (Finset α), (∀ t ∈ 𝒞, t ⊆ insert a s) →
∀ t ∈ 𝒞.nonMemberSubfamily a, t ⊆ s := by
rintro 𝒞 h𝒞 t ht
rw [mem_nonMemberSubfamily] at ht
exact (subset_insert_iff_of_not_mem ht.2).1 (h𝒞 _ ht.1)
have h₁ : ∀ 𝒞 : Finset (Finset α), (∀ t ∈ 𝒞, t ⊆ insert a s) →
∀ t ∈ 𝒞.memberSubfamily a, t ⊆ s := by
rintro 𝒞 h𝒞 t ht
rw [mem_memberSubfamily] at ht
exact (subset_insert_iff_of_not_mem ht.2).1 ((subset_insert _ _).trans <| h𝒞 _ ht.1)
refine mul_le_mul_left' ?_ _
refine (add_le_add (ih h𝒜.memberSubfamily hℬ.memberSubfamily (h₁ _ h𝒜s) <| h₁ _ hℬs) <|
ih h𝒜.nonMemberSubfamily hℬ.nonMemberSubfamily (h₀ _ h𝒜s) <| h₀ _ hℬs).trans_eq ?_
rw [← mul_add, ← memberSubfamily_inter, ← nonMemberSubfamily_inter,
card_memberSubfamily_add_card_nonMemberSubfamily]
#align is_lower_set.le_card_inter_finset' IsLowerSet.le_card_inter_finset'
variable [Fintype α]
theorem IsLowerSet.le_card_inter_finset (h𝒜 : IsLowerSet (𝒜 : Set (Finset α)))
(hℬ : IsLowerSet (ℬ : Set (Finset α))) : 𝒜.card * ℬ.card ≤ 2 ^ Fintype.card α * (𝒜 ∩ ℬ).card :=
h𝒜.le_card_inter_finset' hℬ (fun _ _ => subset_univ _) fun _ _ => subset_univ _
#align is_lower_set.le_card_inter_finset IsLowerSet.le_card_inter_finset
| Mathlib/Combinatorics/SetFamily/HarrisKleitman.lean | 103 | 110 | theorem IsUpperSet.card_inter_le_finset (h𝒜 : IsUpperSet (𝒜 : Set (Finset α)))
(hℬ : IsLowerSet (ℬ : Set (Finset α))) :
2 ^ Fintype.card α * (𝒜 ∩ ℬ).card ≤ 𝒜.card * ℬ.card := by |
rw [← isLowerSet_compl, ← coe_compl] at h𝒜
have := h𝒜.le_card_inter_finset hℬ
rwa [card_compl, Fintype.card_finset, tsub_mul, tsub_le_iff_tsub_le, ← mul_tsub, ←
card_sdiff inter_subset_right, sdiff_inter_self_right, sdiff_compl,
_root_.inf_comm] at this
| 0 |
import Mathlib.Analysis.NormedSpace.Basic
import Mathlib.Analysis.Normed.Group.Hom
import Mathlib.Data.Real.Sqrt
import Mathlib.RingTheory.Ideal.QuotientOperations
import Mathlib.Topology.MetricSpace.HausdorffDistance
#align_import analysis.normed.group.quotient from "leanprover-community/mathlib"@"2196ab363eb097c008d4497125e0dde23fb36db2"
noncomputable section
open QuotientAddGroup Metric Set Topology NNReal
variable {M N : Type*} [SeminormedAddCommGroup M] [SeminormedAddCommGroup N]
noncomputable instance normOnQuotient (S : AddSubgroup M) : Norm (M ⧸ S) where
norm x := sInf (norm '' { m | mk' S m = x })
#align norm_on_quotient normOnQuotient
theorem AddSubgroup.quotient_norm_eq {S : AddSubgroup M} (x : M ⧸ S) :
‖x‖ = sInf (norm '' { m : M | (m : M ⧸ S) = x }) :=
rfl
#align add_subgroup.quotient_norm_eq AddSubgroup.quotient_norm_eq
theorem QuotientAddGroup.norm_eq_infDist {S : AddSubgroup M} (x : M ⧸ S) :
‖x‖ = infDist 0 { m : M | (m : M ⧸ S) = x } := by
simp only [AddSubgroup.quotient_norm_eq, infDist_eq_iInf, sInf_image', dist_zero_left]
theorem QuotientAddGroup.norm_mk {S : AddSubgroup M} (x : M) :
‖(x : M ⧸ S)‖ = infDist x S := by
rw [norm_eq_infDist, ← infDist_image (IsometryEquiv.subLeft x).isometry,
IsometryEquiv.subLeft_apply, sub_zero, ← IsometryEquiv.preimage_symm]
congr 1 with y
simp only [mem_preimage, IsometryEquiv.subLeft_symm_apply, mem_setOf_eq, QuotientAddGroup.eq,
neg_add, neg_neg, neg_add_cancel_right, SetLike.mem_coe]
theorem image_norm_nonempty {S : AddSubgroup M} (x : M ⧸ S) :
(norm '' { m | mk' S m = x }).Nonempty :=
.image _ <| Quot.exists_rep x
#align image_norm_nonempty image_norm_nonempty
theorem bddBelow_image_norm (s : Set M) : BddBelow (norm '' s) :=
⟨0, forall_mem_image.2 fun _ _ ↦ norm_nonneg _⟩
#align bdd_below_image_norm bddBelow_image_norm
theorem isGLB_quotient_norm {S : AddSubgroup M} (x : M ⧸ S) :
IsGLB (norm '' { m | mk' S m = x }) (‖x‖) :=
isGLB_csInf (image_norm_nonempty x) (bddBelow_image_norm _)
| Mathlib/Analysis/Normed/Group/Quotient.lean | 141 | 144 | theorem quotient_norm_neg {S : AddSubgroup M} (x : M ⧸ S) : ‖-x‖ = ‖x‖ := by |
simp only [AddSubgroup.quotient_norm_eq]
congr 1 with r
constructor <;> { rintro ⟨m, hm, rfl⟩; use -m; simpa [neg_eq_iff_eq_neg] using hm }
| 0 |
import Mathlib.CategoryTheory.Sites.Whiskering
import Mathlib.CategoryTheory.Sites.Plus
#align_import category_theory.sites.compatible_plus from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a"
noncomputable section
namespace CategoryTheory.GrothendieckTopology
open CategoryTheory Limits Opposite
universe w₁ w₂ v u
variable {C : Type u} [Category.{v} C] (J : GrothendieckTopology C)
variable {D : Type w₁} [Category.{max v u} D]
variable {E : Type w₂} [Category.{max v u} E]
variable (F : D ⥤ E)
variable [∀ (α β : Type max v u) (fst snd : β → α), HasLimitsOfShape (WalkingMulticospan fst snd) D]
variable [∀ (α β : Type max v u) (fst snd : β → α), HasLimitsOfShape (WalkingMulticospan fst snd) E]
variable [∀ (X : C) (W : J.Cover X) (P : Cᵒᵖ ⥤ D), PreservesLimit (W.index P).multicospan F]
variable (P : Cᵒᵖ ⥤ D)
def diagramCompIso (X : C) : J.diagram P X ⋙ F ≅ J.diagram (P ⋙ F) X :=
NatIso.ofComponents
(fun W => by
refine ?_ ≪≫ HasLimit.isoOfNatIso (W.unop.multicospanComp _ _).symm
refine
(isLimitOfPreserves F (limit.isLimit _)).conePointUniqueUpToIso (limit.isLimit _))
(by
intro A B f
-- Porting note: this used to work with `ext`
-- See https://github.com/leanprover-community/mathlib4/issues/5229
apply Multiequalizer.hom_ext
dsimp
simp only [Functor.mapCone_π_app, Multiequalizer.multifork_π_app_left, Iso.symm_hom,
Multiequalizer.lift_ι, eqToHom_refl, Category.comp_id,
limit.conePointUniqueUpToIso_hom_comp,
GrothendieckTopology.Cover.multicospanComp_hom_inv_left, HasLimit.isoOfNatIso_hom_π,
Category.assoc]
simp only [← F.map_comp, limit.lift_π, Multifork.ofι_π_app, implies_true])
#align category_theory.grothendieck_topology.diagram_comp_iso CategoryTheory.GrothendieckTopology.diagramCompIso
@[reassoc (attr := simp)]
theorem diagramCompIso_hom_ι (X : C) (W : (J.Cover X)ᵒᵖ) (i : W.unop.Arrow) :
(J.diagramCompIso F P X).hom.app W ≫ Multiequalizer.ι ((unop W).index (P ⋙ F)) i =
F.map (Multiequalizer.ι _ _) := by
delta diagramCompIso
dsimp
simp
#align category_theory.grothendieck_topology.diagram_comp_iso_hom_ι CategoryTheory.GrothendieckTopology.diagramCompIso_hom_ι
variable [∀ X : C, HasColimitsOfShape (J.Cover X)ᵒᵖ D]
variable [∀ X : C, HasColimitsOfShape (J.Cover X)ᵒᵖ E]
variable [∀ X : C, PreservesColimitsOfShape (J.Cover X)ᵒᵖ F]
def plusCompIso : J.plusObj P ⋙ F ≅ J.plusObj (P ⋙ F) :=
NatIso.ofComponents
(fun X => by
refine ?_ ≪≫ HasColimit.isoOfNatIso (J.diagramCompIso F P X.unop)
refine
(isColimitOfPreserves F
(colimit.isColimit (J.diagram P (unop X)))).coconePointUniqueUpToIso
(colimit.isColimit _))
(by
intro X Y f
apply (isColimitOfPreserves F (colimit.isColimit (J.diagram P X.unop))).hom_ext
intro W
dsimp [plusObj, plusMap]
simp only [Functor.map_comp, Category.assoc]
slice_rhs 1 2 =>
erw [(isColimitOfPreserves F (colimit.isColimit (J.diagram P X.unop))).fac]
slice_lhs 1 3 =>
simp only [← F.map_comp]
dsimp [colimMap, IsColimit.map, colimit.pre]
simp only [colimit.ι_desc_assoc, colimit.ι_desc]
dsimp [Cocones.precompose]
simp only [Category.assoc, colimit.ι_desc]
dsimp [Cocone.whisker]
rw [F.map_comp]
simp only [Category.assoc]
slice_lhs 2 3 =>
erw [(isColimitOfPreserves F (colimit.isColimit (J.diagram P Y.unop))).fac]
dsimp
simp only [HasColimit.isoOfNatIso_ι_hom_assoc, GrothendieckTopology.diagramPullback_app,
colimit.ι_pre, HasColimit.isoOfNatIso_ι_hom, ι_colimMap_assoc]
simp only [← Category.assoc]
dsimp
congr 1
ext
dsimp
simp only [Category.assoc]
erw [Multiequalizer.lift_ι, diagramCompIso_hom_ι, diagramCompIso_hom_ι, ← F.map_comp,
Multiequalizer.lift_ι])
#align category_theory.grothendieck_topology.plus_comp_iso CategoryTheory.GrothendieckTopology.plusCompIso
@[reassoc (attr := simp)]
| Mathlib/CategoryTheory/Sites/CompatiblePlus.lean | 115 | 128 | theorem ι_plusCompIso_hom (X) (W) :
F.map (colimit.ι _ W) ≫ (J.plusCompIso F P).hom.app X =
(J.diagramCompIso F P X.unop).hom.app W ≫ colimit.ι _ W := by |
delta diagramCompIso plusCompIso
simp only [IsColimit.descCoconeMorphism_hom, IsColimit.uniqueUpToIso_hom,
Cocones.forget_map, Iso.trans_hom, NatIso.ofComponents_hom_app, Functor.mapIso_hom, ←
Category.assoc]
erw [(isColimitOfPreserves F (colimit.isColimit (J.diagram P (unop X)))).fac]
simp only [Category.assoc, HasLimit.isoOfNatIso_hom_π, Iso.symm_hom,
Cover.multicospanComp_hom_inv_left, eqToHom_refl, Category.comp_id,
limit.conePointUniqueUpToIso_hom_comp, Functor.mapCone_π_app,
Multiequalizer.multifork_π_app_left, Multiequalizer.lift_ι, Functor.map_comp, eq_self_iff_true,
Category.assoc, Iso.trans_hom, Iso.cancel_iso_hom_left, NatIso.ofComponents_hom_app,
colimit.cocone_ι, Category.assoc, HasColimit.isoOfNatIso_ι_hom]
| 0 |
import Mathlib.Topology.MetricSpace.HausdorffDistance
import Mathlib.MeasureTheory.Constructions.BorelSpace.Order
#align_import measure_theory.measure.regular from "leanprover-community/mathlib"@"bf6a01357ff5684b1ebcd0f1a13be314fc82c0bf"
open Set Filter ENNReal Topology NNReal TopologicalSpace
namespace MeasureTheory
namespace Measure
def InnerRegularWRT {α} {_ : MeasurableSpace α} (μ : Measure α) (p q : Set α → Prop) :=
∀ ⦃U⦄, q U → ∀ r < μ U, ∃ K, K ⊆ U ∧ p K ∧ r < μ K
#align measure_theory.measure.inner_regular MeasureTheory.Measure.InnerRegularWRT
variable {α β : Type*} [MeasurableSpace α] [TopologicalSpace α] {μ : Measure α}
class OuterRegular (μ : Measure α) : Prop where
protected outerRegular :
∀ ⦃A : Set α⦄, MeasurableSet A → ∀ r > μ A, ∃ U, U ⊇ A ∧ IsOpen U ∧ μ U < r
#align measure_theory.measure.outer_regular MeasureTheory.Measure.OuterRegular
#align measure_theory.measure.outer_regular.outer_regular MeasureTheory.Measure.OuterRegular.outerRegular
class Regular (μ : Measure α) extends IsFiniteMeasureOnCompacts μ, OuterRegular μ : Prop where
innerRegular : InnerRegularWRT μ IsCompact IsOpen
#align measure_theory.measure.regular MeasureTheory.Measure.Regular
class WeaklyRegular (μ : Measure α) extends OuterRegular μ : Prop where
protected innerRegular : InnerRegularWRT μ IsClosed IsOpen
#align measure_theory.measure.weakly_regular MeasureTheory.Measure.WeaklyRegular
#align measure_theory.measure.weakly_regular.inner_regular MeasureTheory.Measure.WeaklyRegular.innerRegular
class InnerRegular (μ : Measure α) : Prop where
protected innerRegular : InnerRegularWRT μ IsCompact (fun s ↦ MeasurableSet s)
class InnerRegularCompactLTTop (μ : Measure α) : Prop where
protected innerRegular : InnerRegularWRT μ IsCompact (fun s ↦ MeasurableSet s ∧ μ s ≠ ∞)
-- see Note [lower instance priority]
instance (priority := 100) Regular.weaklyRegular [R1Space α] [Regular μ] :
WeaklyRegular μ where
innerRegular := fun _U hU r hr ↦
let ⟨K, KU, K_comp, hK⟩ := Regular.innerRegular hU r hr
⟨closure K, K_comp.closure_subset_of_isOpen hU KU, isClosed_closure,
hK.trans_le (measure_mono subset_closure)⟩
#align measure_theory.measure.regular.weakly_regular MeasureTheory.Measure.Regular.weaklyRegular
namespace OuterRegular
instance zero : OuterRegular (0 : Measure α) :=
⟨fun A _ _r hr => ⟨univ, subset_univ A, isOpen_univ, hr⟩⟩
#align measure_theory.measure.outer_regular.zero MeasureTheory.Measure.OuterRegular.zero
| Mathlib/MeasureTheory/Measure/Regular.lean | 339 | 344 | theorem _root_.Set.exists_isOpen_lt_of_lt [OuterRegular μ] (A : Set α) (r : ℝ≥0∞) (hr : μ A < r) :
∃ U, U ⊇ A ∧ IsOpen U ∧ μ U < r := by |
rcases OuterRegular.outerRegular (measurableSet_toMeasurable μ A) r
(by rwa [measure_toMeasurable]) with
⟨U, hAU, hUo, hU⟩
exact ⟨U, (subset_toMeasurable _ _).trans hAU, hUo, hU⟩
| 0 |
import Mathlib.NumberTheory.LegendreSymbol.QuadraticReciprocity
#align_import number_theory.legendre_symbol.jacobi_symbol from "leanprover-community/mathlib"@"74a27133cf29446a0983779e37c8f829a85368f3"
section Jacobi
open Nat ZMod
-- Since we need the fact that the factors are prime, we use `List.pmap`.
def jacobiSym (a : ℤ) (b : ℕ) : ℤ :=
(b.factors.pmap (fun p pp => @legendreSym p ⟨pp⟩ a) fun _ pf => prime_of_mem_factors pf).prod
#align jacobi_sym jacobiSym
-- Notation for the Jacobi symbol.
@[inherit_doc]
scoped[NumberTheorySymbols] notation "J(" a " | " b ")" => jacobiSym a b
-- Porting note: Without the following line, Lean expected `|` on several lines, e.g. line 102.
open NumberTheorySymbols
namespace jacobiSym
@[simp]
theorem zero_right (a : ℤ) : J(a | 0) = 1 := by
simp only [jacobiSym, factors_zero, List.prod_nil, List.pmap]
#align jacobi_sym.zero_right jacobiSym.zero_right
@[simp]
theorem one_right (a : ℤ) : J(a | 1) = 1 := by
simp only [jacobiSym, factors_one, List.prod_nil, List.pmap]
#align jacobi_sym.one_right jacobiSym.one_right
theorem legendreSym.to_jacobiSym (p : ℕ) [fp : Fact p.Prime] (a : ℤ) :
legendreSym p a = J(a | p) := by
simp only [jacobiSym, factors_prime fp.1, List.prod_cons, List.prod_nil, mul_one, List.pmap]
#align legendre_sym.to_jacobi_sym jacobiSym.legendreSym.to_jacobiSym
| Mathlib/NumberTheory/LegendreSymbol/JacobiSymbol.lean | 122 | 126 | theorem mul_right' (a : ℤ) {b₁ b₂ : ℕ} (hb₁ : b₁ ≠ 0) (hb₂ : b₂ ≠ 0) :
J(a | b₁ * b₂) = J(a | b₁) * J(a | b₂) := by |
rw [jacobiSym, ((perm_factors_mul hb₁ hb₂).pmap _).prod_eq, List.pmap_append, List.prod_append]
case h => exact fun p hp => (List.mem_append.mp hp).elim prime_of_mem_factors prime_of_mem_factors
case _ => rfl
| 0 |
import Mathlib.MeasureTheory.Integral.SetIntegral
import Mathlib.MeasureTheory.Measure.Lebesgue.Basic
import Mathlib.MeasureTheory.Measure.Haar.Unique
#align_import measure_theory.measure.lebesgue.integral from "leanprover-community/mathlib"@"fd5edc43dc4f10b85abfe544b88f82cf13c5f844"
open Set Filter MeasureTheory MeasureTheory.Measure TopologicalSpace
section SummableNormIcc
open ContinuousMap
| Mathlib/MeasureTheory/Measure/Lebesgue/Integral.lean | 55 | 69 | theorem Real.integrable_of_summable_norm_Icc {E : Type*} [NormedAddCommGroup E] {f : C(ℝ, E)}
(hf : Summable fun n : ℤ => ‖(f.comp <| ContinuousMap.addRight n).restrict (Icc 0 1)‖) :
Integrable f := by |
refine integrable_of_summable_norm_restrict (.of_nonneg_of_le
(fun n : ℤ => mul_nonneg (norm_nonneg
(f.restrict (⟨Icc (n : ℝ) ((n : ℝ) + 1), isCompact_Icc⟩ : Compacts ℝ)))
ENNReal.toReal_nonneg) (fun n => ?_) hf) ?_
· simp only [Compacts.coe_mk, Real.volume_Icc, add_sub_cancel_left,
ENNReal.toReal_ofReal zero_le_one, mul_one, norm_le _ (norm_nonneg _)]
intro x
have := ((f.comp <| ContinuousMap.addRight n).restrict (Icc 0 1)).norm_coe_le_norm
⟨x - n, ⟨sub_nonneg.mpr x.2.1, sub_le_iff_le_add'.mpr x.2.2⟩⟩
simpa only [ContinuousMap.restrict_apply, comp_apply, coe_addRight, Subtype.coe_mk,
sub_add_cancel] using this
· exact iUnion_Icc_intCast ℝ
| 0 |
import Mathlib.Analysis.Convex.Jensen
import Mathlib.Analysis.Convex.SpecificFunctions.Basic
import Mathlib.Analysis.SpecialFunctions.Pow.NNReal
import Mathlib.Data.Real.ConjExponents
#align_import analysis.mean_inequalities from "leanprover-community/mathlib"@"8f9fea08977f7e450770933ee6abb20733b47c92"
universe u v
open scoped Classical
open Finset NNReal ENNReal
set_option linter.uppercaseLean3 false
noncomputable section
variable {ι : Type u} (s : Finset ι)
section GeomMeanLEArithMean
namespace Real
theorem geom_mean_le_arith_mean_weighted (w z : ι → ℝ) (hw : ∀ i ∈ s, 0 ≤ w i)
(hw' : ∑ i ∈ s, w i = 1) (hz : ∀ i ∈ s, 0 ≤ z i) :
∏ i ∈ s, z i ^ w i ≤ ∑ i ∈ s, w i * z i := by
-- If some number `z i` equals zero and has non-zero weight, then LHS is 0 and RHS is nonnegative.
by_cases A : ∃ i ∈ s, z i = 0 ∧ w i ≠ 0
· rcases A with ⟨i, his, hzi, hwi⟩
rw [prod_eq_zero his]
· exact sum_nonneg fun j hj => mul_nonneg (hw j hj) (hz j hj)
· rw [hzi]
exact zero_rpow hwi
-- If all numbers `z i` with non-zero weight are positive, then we apply Jensen's inequality
-- for `exp` and numbers `log (z i)` with weights `w i`.
· simp only [not_exists, not_and, Ne, Classical.not_not] at A
have := convexOn_exp.map_sum_le hw hw' fun i _ => Set.mem_univ <| log (z i)
simp only [exp_sum, (· ∘ ·), smul_eq_mul, mul_comm (w _) (log _)] at this
convert this using 1 <;> [apply prod_congr rfl;apply sum_congr rfl] <;> intro i hi
· cases' eq_or_lt_of_le (hz i hi) with hz hz
· simp [A i hi hz.symm]
· exact rpow_def_of_pos hz _
· cases' eq_or_lt_of_le (hz i hi) with hz hz
· simp [A i hi hz.symm]
· rw [exp_log hz]
#align real.geom_mean_le_arith_mean_weighted Real.geom_mean_le_arith_mean_weighted
| Mathlib/Analysis/MeanInequalities.lean | 138 | 148 | theorem geom_mean_le_arith_mean {ι : Type*} (s : Finset ι) (w : ι → ℝ) (z : ι → ℝ)
(hw : ∀ i ∈ s, 0 ≤ w i) (hw' : 0 < ∑ i ∈ s, w i) (hz : ∀ i ∈ s, 0 ≤ z i) :
(∏ i ∈ s, z i ^ w i) ^ (∑ i ∈ s, w i)⁻¹ ≤ (∑ i ∈ s, w i * z i) / (∑ i ∈ s, w i) := by |
convert geom_mean_le_arith_mean_weighted s (fun i => (w i) / ∑ i ∈ s, w i) z ?_ ?_ hz using 2
· rw [← finset_prod_rpow _ _ (fun i hi => rpow_nonneg (hz _ hi) _) _]
refine Finset.prod_congr rfl (fun _ ih => ?_)
rw [div_eq_mul_inv, rpow_mul (hz _ ih)]
· simp_rw [div_eq_mul_inv, mul_assoc, mul_comm, ← mul_assoc, ← Finset.sum_mul, mul_comm]
· exact fun _ hi => div_nonneg (hw _ hi) (le_of_lt hw')
· simp_rw [div_eq_mul_inv, ← Finset.sum_mul]
exact mul_inv_cancel (by linarith)
| 0 |
import Mathlib.Probability.Martingale.Convergence
import Mathlib.Probability.Martingale.OptionalStopping
import Mathlib.Probability.Martingale.Centering
#align_import probability.martingale.borel_cantelli from "leanprover-community/mathlib"@"2196ab363eb097c008d4497125e0dde23fb36db2"
open Filter
open scoped NNReal ENNReal MeasureTheory ProbabilityTheory BigOperators Topology
namespace MeasureTheory
variable {Ω : Type*} {m0 : MeasurableSpace Ω} {μ : Measure Ω} {ℱ : Filtration ℕ m0} {f : ℕ → Ω → ℝ}
{ω : Ω}
-- TODO: `leastGE` should be defined taking values in `WithTop ℕ` once the `stoppedProcess`
-- refactor is complete
noncomputable def leastGE (f : ℕ → Ω → ℝ) (r : ℝ) (n : ℕ) :=
hitting f (Set.Ici r) 0 n
#align measure_theory.least_ge MeasureTheory.leastGE
theorem Adapted.isStoppingTime_leastGE (r : ℝ) (n : ℕ) (hf : Adapted ℱ f) :
IsStoppingTime ℱ (leastGE f r n) :=
hitting_isStoppingTime hf measurableSet_Ici
#align measure_theory.adapted.is_stopping_time_least_ge MeasureTheory.Adapted.isStoppingTime_leastGE
theorem leastGE_le {i : ℕ} {r : ℝ} (ω : Ω) : leastGE f r i ω ≤ i :=
hitting_le ω
#align measure_theory.least_ge_le MeasureTheory.leastGE_le
-- The following four lemmas shows `leastGE` behaves like a stopped process. Ideally we should
-- define `leastGE` as a stopping time and take its stopped process. However, we can't do that
-- with our current definition since a stopping time takes only finite indicies. An upcomming
-- refactor should hopefully make it possible to have stopping times taking infinity as a value
theorem leastGE_mono {n m : ℕ} (hnm : n ≤ m) (r : ℝ) (ω : Ω) : leastGE f r n ω ≤ leastGE f r m ω :=
hitting_mono hnm
#align measure_theory.least_ge_mono MeasureTheory.leastGE_mono
theorem leastGE_eq_min (π : Ω → ℕ) (r : ℝ) (ω : Ω) {n : ℕ} (hπn : ∀ ω, π ω ≤ n) :
leastGE f r (π ω) ω = min (π ω) (leastGE f r n ω) := by
classical
refine le_antisymm (le_min (leastGE_le _) (leastGE_mono (hπn ω) r ω)) ?_
by_cases hle : π ω ≤ leastGE f r n ω
· rw [min_eq_left hle, leastGE]
by_cases h : ∃ j ∈ Set.Icc 0 (π ω), f j ω ∈ Set.Ici r
· refine hle.trans (Eq.le ?_)
rw [leastGE, ← hitting_eq_hitting_of_exists (hπn ω) h]
· simp only [hitting, if_neg h, le_rfl]
· rw [min_eq_right (not_le.1 hle).le, leastGE, leastGE, ←
hitting_eq_hitting_of_exists (hπn ω) _]
rw [not_le, leastGE, hitting_lt_iff _ (hπn ω)] at hle
exact
let ⟨j, hj₁, hj₂⟩ := hle
⟨j, ⟨hj₁.1, hj₁.2.le⟩, hj₂⟩
#align measure_theory.least_ge_eq_min MeasureTheory.leastGE_eq_min
theorem stoppedValue_stoppedValue_leastGE (f : ℕ → Ω → ℝ) (π : Ω → ℕ) (r : ℝ) {n : ℕ}
(hπn : ∀ ω, π ω ≤ n) : stoppedValue (fun i => stoppedValue f (leastGE f r i)) π =
stoppedValue (stoppedProcess f (leastGE f r n)) π := by
ext1 ω
simp (config := { unfoldPartialApp := true }) only [stoppedProcess, stoppedValue]
rw [leastGE_eq_min _ _ _ hπn]
#align measure_theory.stopped_value_stopped_value_least_ge MeasureTheory.stoppedValue_stoppedValue_leastGE
| Mathlib/Probability/Martingale/BorelCantelli.lean | 101 | 115 | theorem Submartingale.stoppedValue_leastGE [IsFiniteMeasure μ] (hf : Submartingale f ℱ μ) (r : ℝ) :
Submartingale (fun i => stoppedValue f (leastGE f r i)) ℱ μ := by |
rw [submartingale_iff_expected_stoppedValue_mono]
· intro σ π hσ hπ hσ_le_π hπ_bdd
obtain ⟨n, hπ_le_n⟩ := hπ_bdd
simp_rw [stoppedValue_stoppedValue_leastGE f σ r fun i => (hσ_le_π i).trans (hπ_le_n i)]
simp_rw [stoppedValue_stoppedValue_leastGE f π r hπ_le_n]
refine hf.expected_stoppedValue_mono ?_ ?_ ?_ fun ω => (min_le_left _ _).trans (hπ_le_n ω)
· exact hσ.min (hf.adapted.isStoppingTime_leastGE _ _)
· exact hπ.min (hf.adapted.isStoppingTime_leastGE _ _)
· exact fun ω => min_le_min (hσ_le_π ω) le_rfl
· exact fun i => stronglyMeasurable_stoppedValue_of_le hf.adapted.progMeasurable_of_discrete
(hf.adapted.isStoppingTime_leastGE _ _) leastGE_le
· exact fun i => integrable_stoppedValue _ (hf.adapted.isStoppingTime_leastGE _ _) hf.integrable
leastGE_le
| 0 |
import Mathlib.Algebra.Homology.ImageToKernel
#align_import algebra.homology.exact from "leanprover-community/mathlib"@"3feb151caefe53df080ca6ca67a0c6685cfd1b82"
universe v v₂ u u₂
open CategoryTheory CategoryTheory.Limits
variable {V : Type u} [Category.{v} V]
variable [HasImages V]
namespace CategoryTheory
-- One nice feature of this definition is that we have
-- `Epi f → Exact g h → Exact (f ≫ g) h` and `Exact f g → Mono h → Exact f (g ≫ h)`,
-- which do not necessarily hold in a non-abelian category with the usual definition of `Exact`.
structure Exact [HasZeroMorphisms V] [HasKernels V] {A B C : V} (f : A ⟶ B) (g : B ⟶ C) : Prop where
w : f ≫ g = 0
epi : Epi (imageToKernel f g w)
#align category_theory.exact CategoryTheory.Exact
-- Porting note: it seems it no longer works in Lean4, so that some `haveI` have been added below
-- This works as an instance even though `Exact` itself is not a class, as long as the goal is
-- literally of the form `Epi (imageToKernel f g h.w)` (where `h : Exact f g`). If the proof of
-- `f ≫ g = 0` looks different, we are out of luck and have to add the instance by hand.
attribute [instance] Exact.epi
attribute [reassoc] Exact.w
section
variable [HasZeroObject V] [Preadditive V] [HasKernels V] [HasCokernels V]
open ZeroObject
theorem Preadditive.exact_iff_homology'_zero {A B C : V} (f : A ⟶ B) (g : B ⟶ C) :
Exact f g ↔ ∃ w : f ≫ g = 0, Nonempty (homology' f g w ≅ 0) :=
⟨fun h => ⟨h.w, ⟨by
haveI := h.epi
exact cokernel.ofEpi _⟩⟩,
fun h => by
obtain ⟨w, ⟨i⟩⟩ := h
exact ⟨w, Preadditive.epi_of_cokernel_zero ((cancel_mono i.hom).mp (by ext))⟩⟩
#align category_theory.preadditive.exact_iff_homology_zero CategoryTheory.Preadditive.exact_iff_homology'_zero
theorem Preadditive.exact_of_iso_of_exact {A₁ B₁ C₁ A₂ B₂ C₂ : V} (f₁ : A₁ ⟶ B₁) (g₁ : B₁ ⟶ C₁)
(f₂ : A₂ ⟶ B₂) (g₂ : B₂ ⟶ C₂) (α : Arrow.mk f₁ ≅ Arrow.mk f₂) (β : Arrow.mk g₁ ≅ Arrow.mk g₂)
(p : α.hom.right = β.hom.left) (h : Exact f₁ g₁) : Exact f₂ g₂ := by
rw [Preadditive.exact_iff_homology'_zero] at h ⊢
rcases h with ⟨w₁, ⟨i⟩⟩
suffices w₂ : f₂ ≫ g₂ = 0 from ⟨w₂, ⟨(homology'.mapIso w₁ w₂ α β p).symm.trans i⟩⟩
rw [← cancel_epi α.hom.left, ← cancel_mono β.inv.right, comp_zero, zero_comp, ← w₁]
have eq₁ := β.inv.w
have eq₂ := α.hom.w
dsimp at eq₁ eq₂
simp only [Category.assoc, Category.assoc, ← eq₁, reassoc_of% eq₂, p,
← reassoc_of% (Arrow.comp_left β.hom β.inv), β.hom_inv_id, Arrow.id_left, Category.id_comp]
#align category_theory.preadditive.exact_of_iso_of_exact CategoryTheory.Preadditive.exact_of_iso_of_exact
theorem Preadditive.exact_of_iso_of_exact' {A₁ B₁ C₁ A₂ B₂ C₂ : V} (f₁ : A₁ ⟶ B₁) (g₁ : B₁ ⟶ C₁)
(f₂ : A₂ ⟶ B₂) (g₂ : B₂ ⟶ C₂) (α : A₁ ≅ A₂) (β : B₁ ≅ B₂) (γ : C₁ ≅ C₂)
(hsq₁ : α.hom ≫ f₂ = f₁ ≫ β.hom) (hsq₂ : β.hom ≫ g₂ = g₁ ≫ γ.hom) (h : Exact f₁ g₁) :
Exact f₂ g₂ :=
Preadditive.exact_of_iso_of_exact f₁ g₁ f₂ g₂ (Arrow.isoMk α β hsq₁) (Arrow.isoMk β γ hsq₂) rfl h
#align category_theory.preadditive.exact_of_iso_of_exact' CategoryTheory.Preadditive.exact_of_iso_of_exact'
theorem Preadditive.exact_iff_exact_of_iso {A₁ B₁ C₁ A₂ B₂ C₂ : V} (f₁ : A₁ ⟶ B₁) (g₁ : B₁ ⟶ C₁)
(f₂ : A₂ ⟶ B₂) (g₂ : B₂ ⟶ C₂) (α : Arrow.mk f₁ ≅ Arrow.mk f₂) (β : Arrow.mk g₁ ≅ Arrow.mk g₂)
(p : α.hom.right = β.hom.left) : Exact f₁ g₁ ↔ Exact f₂ g₂ :=
⟨Preadditive.exact_of_iso_of_exact _ _ _ _ _ _ p,
Preadditive.exact_of_iso_of_exact _ _ _ _ α.symm β.symm
(by
rw [← cancel_mono α.hom.right]
simp only [Iso.symm_hom, ← Arrow.comp_right, α.inv_hom_id]
simp only [p, ← Arrow.comp_left, Arrow.id_right, Arrow.id_left, Iso.inv_hom_id]
rfl)⟩
#align category_theory.preadditive.exact_iff_exact_of_iso CategoryTheory.Preadditive.exact_iff_exact_of_iso
end
section
variable [HasZeroMorphisms V] [HasKernels V]
| Mathlib/Algebra/Homology/Exact.lean | 140 | 144 | theorem comp_eq_zero_of_image_eq_kernel {A B C : V} (f : A ⟶ B) (g : B ⟶ C)
(p : imageSubobject f = kernelSubobject g) : f ≫ g = 0 := by |
suffices Subobject.arrow (imageSubobject f) ≫ g = 0 by
rw [← imageSubobject_arrow_comp f, Category.assoc, this, comp_zero]
rw [p, kernelSubobject_arrow_comp]
| 0 |
import Mathlib.Algebra.IsPrimePow
import Mathlib.Data.Nat.Factorization.Basic
#align_import data.nat.factorization.prime_pow from "leanprover-community/mathlib"@"6ca1a09bc9aa75824bf97388c9e3b441fc4ccf3f"
variable {R : Type*} [CommMonoidWithZero R] (n p : R) (k : ℕ)
theorem IsPrimePow.minFac_pow_factorization_eq {n : ℕ} (hn : IsPrimePow n) :
n.minFac ^ n.factorization n.minFac = n := by
obtain ⟨p, k, hp, hk, rfl⟩ := hn
rw [← Nat.prime_iff] at hp
rw [hp.pow_minFac hk.ne', hp.factorization_pow, Finsupp.single_eq_same]
#align is_prime_pow.min_fac_pow_factorization_eq IsPrimePow.minFac_pow_factorization_eq
theorem isPrimePow_of_minFac_pow_factorization_eq {n : ℕ}
(h : n.minFac ^ n.factorization n.minFac = n) (hn : n ≠ 1) : IsPrimePow n := by
rcases eq_or_ne n 0 with (rfl | hn')
· simp_all
refine ⟨_, _, (Nat.minFac_prime hn).prime, ?_, h⟩
simp [pos_iff_ne_zero, ← Finsupp.mem_support_iff, Nat.support_factorization, hn',
Nat.minFac_prime hn, Nat.minFac_dvd]
#align is_prime_pow_of_min_fac_pow_factorization_eq isPrimePow_of_minFac_pow_factorization_eq
theorem isPrimePow_iff_minFac_pow_factorization_eq {n : ℕ} (hn : n ≠ 1) :
IsPrimePow n ↔ n.minFac ^ n.factorization n.minFac = n :=
⟨fun h => h.minFac_pow_factorization_eq, fun h => isPrimePow_of_minFac_pow_factorization_eq h hn⟩
#align is_prime_pow_iff_min_fac_pow_factorization_eq isPrimePow_iff_minFac_pow_factorization_eq
theorem isPrimePow_iff_factorization_eq_single {n : ℕ} :
IsPrimePow n ↔ ∃ p k : ℕ, 0 < k ∧ n.factorization = Finsupp.single p k := by
rw [isPrimePow_nat_iff]
refine exists₂_congr fun p k => ?_
constructor
· rintro ⟨hp, hk, hn⟩
exact ⟨hk, by rw [← hn, Nat.Prime.factorization_pow hp]⟩
· rintro ⟨hk, hn⟩
have hn0 : n ≠ 0 := by
rintro rfl
simp_all only [Finsupp.single_eq_zero, eq_comm, Nat.factorization_zero, hk.ne']
rw [Nat.eq_pow_of_factorization_eq_single hn0 hn]
exact ⟨Nat.prime_of_mem_primeFactors <|
Finsupp.mem_support_iff.2 (by simp [hn, hk.ne'] : n.factorization p ≠ 0), hk, rfl⟩
#align is_prime_pow_iff_factorization_eq_single isPrimePow_iff_factorization_eq_single
| Mathlib/Data/Nat/Factorization/PrimePow.lean | 57 | 60 | theorem isPrimePow_iff_card_primeFactors_eq_one {n : ℕ} :
IsPrimePow n ↔ n.primeFactors.card = 1 := by |
simp_rw [isPrimePow_iff_factorization_eq_single, ← Nat.support_factorization,
Finsupp.card_support_eq_one', pos_iff_ne_zero]
| 0 |
import Mathlib.SetTheory.Ordinal.Arithmetic
import Mathlib.SetTheory.Ordinal.Exponential
#align_import set_theory.ordinal.cantor_normal_form from "leanprover-community/mathlib"@"991ff3b5269848f6dd942ae8e9dd3c946035dc8b"
noncomputable section
universe u
open List
namespace Ordinal
@[elab_as_elim]
noncomputable def CNFRec (b : Ordinal) {C : Ordinal → Sort*} (H0 : C 0)
(H : ∀ o, o ≠ 0 → C (o % b ^ log b o) → C o) : ∀ o, C o := fun o ↦ by
by_cases h : o = 0
· rw [h]; exact H0
· exact H o h (CNFRec _ H0 H (o % b ^ log b o))
termination_by o => o
decreasing_by exact mod_opow_log_lt_self b h
set_option linter.uppercaseLean3 false in
#align ordinal.CNF_rec Ordinal.CNFRec
@[simp]
theorem CNFRec_zero {C : Ordinal → Sort*} (b : Ordinal) (H0 : C 0)
(H : ∀ o, o ≠ 0 → C (o % b ^ log b o) → C o) : @CNFRec b C H0 H 0 = H0 := by
rw [CNFRec, dif_pos rfl]
rfl
set_option linter.uppercaseLean3 false in
#align ordinal.CNF_rec_zero Ordinal.CNFRec_zero
theorem CNFRec_pos (b : Ordinal) {o : Ordinal} {C : Ordinal → Sort*} (ho : o ≠ 0) (H0 : C 0)
(H : ∀ o, o ≠ 0 → C (o % b ^ log b o) → C o) :
@CNFRec b C H0 H o = H o ho (@CNFRec b C H0 H _) := by rw [CNFRec, dif_neg ho]
set_option linter.uppercaseLean3 false in
#align ordinal.CNF_rec_pos Ordinal.CNFRec_pos
-- Porting note: unknown attribute @[pp_nodot]
def CNF (b o : Ordinal) : List (Ordinal × Ordinal) :=
CNFRec b [] (fun o _ho IH ↦ (log b o, o / b ^ log b o)::IH) o
set_option linter.uppercaseLean3 false in
#align ordinal.CNF Ordinal.CNF
@[simp]
theorem CNF_zero (b : Ordinal) : CNF b 0 = [] :=
CNFRec_zero b _ _
set_option linter.uppercaseLean3 false in
#align ordinal.CNF_zero Ordinal.CNF_zero
theorem CNF_ne_zero {b o : Ordinal} (ho : o ≠ 0) :
CNF b o = (log b o, o / b ^ log b o)::CNF b (o % b ^ log b o) :=
CNFRec_pos b ho _ _
set_option linter.uppercaseLean3 false in
#align ordinal.CNF_ne_zero Ordinal.CNF_ne_zero
theorem zero_CNF {o : Ordinal} (ho : o ≠ 0) : CNF 0 o = [⟨0, o⟩] := by simp [CNF_ne_zero ho]
set_option linter.uppercaseLean3 false in
#align ordinal.zero_CNF Ordinal.zero_CNF
theorem one_CNF {o : Ordinal} (ho : o ≠ 0) : CNF 1 o = [⟨0, o⟩] := by simp [CNF_ne_zero ho]
set_option linter.uppercaseLean3 false in
#align ordinal.one_CNF Ordinal.one_CNF
theorem CNF_of_le_one {b o : Ordinal} (hb : b ≤ 1) (ho : o ≠ 0) : CNF b o = [⟨0, o⟩] := by
rcases le_one_iff.1 hb with (rfl | rfl)
· exact zero_CNF ho
· exact one_CNF ho
set_option linter.uppercaseLean3 false in
#align ordinal.CNF_of_le_one Ordinal.CNF_of_le_one
theorem CNF_of_lt {b o : Ordinal} (ho : o ≠ 0) (hb : o < b) : CNF b o = [⟨0, o⟩] := by
simp only [CNF_ne_zero ho, log_eq_zero hb, opow_zero, div_one, mod_one, CNF_zero]
set_option linter.uppercaseLean3 false in
#align ordinal.CNF_of_lt Ordinal.CNF_of_lt
theorem CNF_foldr (b o : Ordinal) : (CNF b o).foldr (fun p r ↦ b ^ p.1 * p.2 + r) 0 = o :=
CNFRec b (by rw [CNF_zero]; rfl)
(fun o ho IH ↦ by rw [CNF_ne_zero ho, foldr_cons, IH, div_add_mod]) o
set_option linter.uppercaseLean3 false in
#align ordinal.CNF_foldr Ordinal.CNF_foldr
theorem CNF_fst_le_log {b o : Ordinal.{u}} {x : Ordinal × Ordinal} :
x ∈ CNF b o → x.1 ≤ log b o := by
refine CNFRec b ?_ (fun o ho H ↦ ?_) o
· rw [CNF_zero]
intro contra; contradiction
· rw [CNF_ne_zero ho, mem_cons]
rintro (rfl | h)
· exact le_rfl
· exact (H h).trans (log_mono_right _ (mod_opow_log_lt_self b ho).le)
set_option linter.uppercaseLean3 false in
#align ordinal.CNF_fst_le_log Ordinal.CNF_fst_le_log
theorem CNF_fst_le {b o : Ordinal.{u}} {x : Ordinal × Ordinal} (h : x ∈ CNF b o) : x.1 ≤ o :=
(CNF_fst_le_log h).trans <| log_le_self _ _
set_option linter.uppercaseLean3 false in
#align ordinal.CNF_fst_le Ordinal.CNF_fst_le
theorem CNF_lt_snd {b o : Ordinal.{u}} {x : Ordinal × Ordinal} : x ∈ CNF b o → 0 < x.2 := by
refine CNFRec b (by simp) (fun o ho IH ↦ ?_) o
rw [CNF_ne_zero ho]
rintro (h | ⟨_, h⟩)
· exact div_opow_log_pos b ho
· exact IH h
set_option linter.uppercaseLean3 false in
#align ordinal.CNF_lt_snd Ordinal.CNF_lt_snd
| Mathlib/SetTheory/Ordinal/CantorNormalForm.lean | 150 | 158 | theorem CNF_snd_lt {b o : Ordinal.{u}} (hb : 1 < b) {x : Ordinal × Ordinal} :
x ∈ CNF b o → x.2 < b := by |
refine CNFRec b ?_ (fun o ho IH ↦ ?_) o
· simp only [CNF_zero, not_mem_nil, IsEmpty.forall_iff]
· rw [CNF_ne_zero ho]
intro h
cases' (mem_cons.mp h) with h h
· rw [h]; simpa only using div_opow_log_lt o hb
· exact IH h
| 0 |
import Mathlib.CategoryTheory.Sites.Plus
import Mathlib.CategoryTheory.Limits.Shapes.ConcreteCategory
#align_import category_theory.sites.sheafification from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a"
namespace CategoryTheory
open CategoryTheory.Limits Opposite
universe w v u
variable {C : Type u} [Category.{v} C] {J : GrothendieckTopology C}
variable {D : Type w} [Category.{max v u} D]
section
variable [ConcreteCategory.{max v u} D]
attribute [local instance] ConcreteCategory.hasCoeToSort ConcreteCategory.instFunLike
-- porting note (#5171): removed @[nolint has_nonempty_instance]
def Meq {X : C} (P : Cᵒᵖ ⥤ D) (S : J.Cover X) :=
{ x : ∀ I : S.Arrow, P.obj (op I.Y) //
∀ I : S.Relation, P.map I.g₁.op (x I.fst) = P.map I.g₂.op (x I.snd) }
#align category_theory.meq CategoryTheory.Meq
end
namespace GrothendieckTopology
variable (J)
variable [∀ (P : Cᵒᵖ ⥤ D) (X : C) (S : J.Cover X), HasMultiequalizer (S.index P)]
[∀ X : C, HasColimitsOfShape (J.Cover X)ᵒᵖ D]
noncomputable def sheafify (P : Cᵒᵖ ⥤ D) : Cᵒᵖ ⥤ D :=
J.plusObj (J.plusObj P)
#align category_theory.grothendieck_topology.sheafify CategoryTheory.GrothendieckTopology.sheafify
noncomputable def toSheafify (P : Cᵒᵖ ⥤ D) : P ⟶ J.sheafify P :=
J.toPlus P ≫ J.plusMap (J.toPlus P)
#align category_theory.grothendieck_topology.to_sheafify CategoryTheory.GrothendieckTopology.toSheafify
noncomputable def sheafifyMap {P Q : Cᵒᵖ ⥤ D} (η : P ⟶ Q) : J.sheafify P ⟶ J.sheafify Q :=
J.plusMap <| J.plusMap η
#align category_theory.grothendieck_topology.sheafify_map CategoryTheory.GrothendieckTopology.sheafifyMap
@[simp]
theorem sheafifyMap_id (P : Cᵒᵖ ⥤ D) : J.sheafifyMap (𝟙 P) = 𝟙 (J.sheafify P) := by
dsimp [sheafifyMap, sheafify]
simp
#align category_theory.grothendieck_topology.sheafify_map_id CategoryTheory.GrothendieckTopology.sheafifyMap_id
@[simp]
theorem sheafifyMap_comp {P Q R : Cᵒᵖ ⥤ D} (η : P ⟶ Q) (γ : Q ⟶ R) :
J.sheafifyMap (η ≫ γ) = J.sheafifyMap η ≫ J.sheafifyMap γ := by
dsimp [sheafifyMap, sheafify]
simp
#align category_theory.grothendieck_topology.sheafify_map_comp CategoryTheory.GrothendieckTopology.sheafifyMap_comp
@[reassoc (attr := simp)]
theorem toSheafify_naturality {P Q : Cᵒᵖ ⥤ D} (η : P ⟶ Q) :
η ≫ J.toSheafify _ = J.toSheafify _ ≫ J.sheafifyMap η := by
dsimp [sheafifyMap, sheafify, toSheafify]
simp
#align category_theory.grothendieck_topology.to_sheafify_naturality CategoryTheory.GrothendieckTopology.toSheafify_naturality
variable (D)
noncomputable def sheafification : (Cᵒᵖ ⥤ D) ⥤ Cᵒᵖ ⥤ D :=
J.plusFunctor D ⋙ J.plusFunctor D
#align category_theory.grothendieck_topology.sheafification CategoryTheory.GrothendieckTopology.sheafification
@[simp]
theorem sheafification_obj (P : Cᵒᵖ ⥤ D) : (J.sheafification D).obj P = J.sheafify P :=
rfl
#align category_theory.grothendieck_topology.sheafification_obj CategoryTheory.GrothendieckTopology.sheafification_obj
@[simp]
theorem sheafification_map {P Q : Cᵒᵖ ⥤ D} (η : P ⟶ Q) :
(J.sheafification D).map η = J.sheafifyMap η :=
rfl
#align category_theory.grothendieck_topology.sheafification_map CategoryTheory.GrothendieckTopology.sheafification_map
noncomputable def toSheafification : 𝟭 _ ⟶ sheafification J D :=
J.toPlusNatTrans D ≫ whiskerRight (J.toPlusNatTrans D) (J.plusFunctor D)
#align category_theory.grothendieck_topology.to_sheafification CategoryTheory.GrothendieckTopology.toSheafification
@[simp]
theorem toSheafification_app (P : Cᵒᵖ ⥤ D) :
(J.toSheafification D).app P = J.toSheafify P :=
rfl
#align category_theory.grothendieck_topology.to_sheafification_app CategoryTheory.GrothendieckTopology.toSheafification_app
variable {D}
| Mathlib/CategoryTheory/Sites/ConcreteSheafification.lean | 529 | 533 | theorem isIso_toSheafify {P : Cᵒᵖ ⥤ D} (hP : Presheaf.IsSheaf J P) : IsIso (J.toSheafify P) := by |
dsimp [toSheafify]
haveI := isIso_toPlus_of_isSheaf J P hP
change (IsIso (toPlus J P ≫ (J.plusFunctor D).map (toPlus J P)))
infer_instance
| 0 |
import Mathlib.Order.Filter.Partial
import Mathlib.Topology.Basic
#align_import topology.partial from "leanprover-community/mathlib"@"4c19a16e4b705bf135cf9a80ac18fcc99c438514"
open Filter
open Topology
variable {X Y : Type*} [TopologicalSpace X]
theorem rtendsto_nhds {r : Rel Y X} {l : Filter Y} {x : X} :
RTendsto r l (𝓝 x) ↔ ∀ s, IsOpen s → x ∈ s → r.core s ∈ l :=
all_mem_nhds_filter _ _ (fun _s _t => id) _
#align rtendsto_nhds rtendsto_nhds
theorem rtendsto'_nhds {r : Rel Y X} {l : Filter Y} {x : X} :
RTendsto' r l (𝓝 x) ↔ ∀ s, IsOpen s → x ∈ s → r.preimage s ∈ l := by
rw [rtendsto'_def]
apply all_mem_nhds_filter
apply Rel.preimage_mono
#align rtendsto'_nhds rtendsto'_nhds
theorem ptendsto_nhds {f : Y →. X} {l : Filter Y} {x : X} :
PTendsto f l (𝓝 x) ↔ ∀ s, IsOpen s → x ∈ s → f.core s ∈ l :=
rtendsto_nhds
#align ptendsto_nhds ptendsto_nhds
theorem ptendsto'_nhds {f : Y →. X} {l : Filter Y} {x : X} :
PTendsto' f l (𝓝 x) ↔ ∀ s, IsOpen s → x ∈ s → f.preimage s ∈ l :=
rtendsto'_nhds
#align ptendsto'_nhds ptendsto'_nhds
variable [TopologicalSpace Y]
def PContinuous (f : X →. Y) :=
∀ s, IsOpen s → IsOpen (f.preimage s)
#align pcontinuous PContinuous
theorem open_dom_of_pcontinuous {f : X →. Y} (h : PContinuous f) : IsOpen f.Dom := by
rw [← PFun.preimage_univ]; exact h _ isOpen_univ
#align open_dom_of_pcontinuous open_dom_of_pcontinuous
| Mathlib/Topology/Partial.lean | 61 | 83 | theorem pcontinuous_iff' {f : X →. Y} :
PContinuous f ↔ ∀ {x y} (h : y ∈ f x), PTendsto' f (𝓝 x) (𝓝 y) := by |
constructor
· intro h x y h'
simp only [ptendsto'_def, mem_nhds_iff]
rintro s ⟨t, tsubs, opent, yt⟩
exact ⟨f.preimage t, PFun.preimage_mono _ tsubs, h _ opent, ⟨y, yt, h'⟩⟩
intro hf s os
rw [isOpen_iff_nhds]
rintro x ⟨y, ys, fxy⟩ t
rw [mem_principal]
intro (h : f.preimage s ⊆ t)
change t ∈ 𝓝 x
apply mem_of_superset _ h
have h' : ∀ s ∈ 𝓝 y, f.preimage s ∈ 𝓝 x := by
intro s hs
have : PTendsto' f (𝓝 x) (𝓝 y) := hf fxy
rw [ptendsto'_def] at this
exact this s hs
show f.preimage s ∈ 𝓝 x
apply h'
rw [mem_nhds_iff]
exact ⟨s, Set.Subset.refl _, os, ys⟩
| 0 |
import Mathlib.Analysis.NormedSpace.OperatorNorm.Bilinear
import Mathlib.Analysis.NormedSpace.OperatorNorm.NNNorm
suppress_compilation
open Bornology Metric Set Real
open Filter hiding map_smul
open scoped Classical NNReal Topology Uniformity
-- the `ₗ` subscript variables are for special cases about linear (as opposed to semilinear) maps
variable {𝕜 𝕜₂ 𝕜₃ E Eₗ F Fₗ G Gₗ 𝓕 : Type*}
variable [NormedAddCommGroup E] [NormedAddCommGroup F] [NormedAddCommGroup G]
[NormedAddCommGroup Fₗ]
variable [NontriviallyNormedField 𝕜] [NontriviallyNormedField 𝕜₂] [NontriviallyNormedField 𝕜₃]
[NormedSpace 𝕜 E] [NormedSpace 𝕜₂ F] [NormedSpace 𝕜₃ G] [NormedSpace 𝕜 Fₗ] (c : 𝕜)
{σ₁₂ : 𝕜 →+* 𝕜₂} {σ₂₃ : 𝕜₂ →+* 𝕜₃} (f g : E →SL[σ₁₂] F) (x y z : E)
namespace ContinuousLinearMap
section Completeness
variable {E' : Type*} [SeminormedAddCommGroup E'] [NormedSpace 𝕜 E'] [RingHomIsometric σ₁₂]
@[simps! (config := .asFn) apply]
def ofMemClosureImageCoeBounded (f : E' → F) {s : Set (E' →SL[σ₁₂] F)} (hs : IsBounded s)
(hf : f ∈ closure (((↑) : (E' →SL[σ₁₂] F) → E' → F) '' s)) : E' →SL[σ₁₂] F := by
-- `f` is a linear map due to `linearMapOfMemClosureRangeCoe`
refine (linearMapOfMemClosureRangeCoe f ?_).mkContinuousOfExistsBound ?_
· refine closure_mono (image_subset_iff.2 fun g _ => ?_) hf
exact ⟨g, rfl⟩
· -- We need to show that `f` has bounded norm. Choose `C` such that `‖g‖ ≤ C` for all `g ∈ s`.
rcases isBounded_iff_forall_norm_le.1 hs with ⟨C, hC⟩
-- Then `‖g x‖ ≤ C * ‖x‖` for all `g ∈ s`, `x : E`, hence `‖f x‖ ≤ C * ‖x‖` for all `x`.
have : ∀ x, IsClosed { g : E' → F | ‖g x‖ ≤ C * ‖x‖ } := fun x =>
isClosed_Iic.preimage (@continuous_apply E' (fun _ => F) _ x).norm
refine ⟨C, fun x => (this x).closure_subset_iff.2 (image_subset_iff.2 fun g hg => ?_) hf⟩
exact g.le_of_opNorm_le (hC _ hg) _
#align continuous_linear_map.of_mem_closure_image_coe_bounded ContinuousLinearMap.ofMemClosureImageCoeBounded
@[simps! (config := .asFn) apply]
def ofTendstoOfBoundedRange {α : Type*} {l : Filter α} [l.NeBot] (f : E' → F)
(g : α → E' →SL[σ₁₂] F) (hf : Tendsto (fun a x => g a x) l (𝓝 f))
(hg : IsBounded (Set.range g)) : E' →SL[σ₁₂] F :=
ofMemClosureImageCoeBounded f hg <| mem_closure_of_tendsto hf <|
eventually_of_forall fun _ => mem_image_of_mem _ <| Set.mem_range_self _
#align continuous_linear_map.of_tendsto_of_bounded_range ContinuousLinearMap.ofTendstoOfBoundedRange
| Mathlib/Analysis/NormedSpace/OperatorNorm/Completeness.lean | 70 | 86 | theorem tendsto_of_tendsto_pointwise_of_cauchySeq {f : ℕ → E' →SL[σ₁₂] F} {g : E' →SL[σ₁₂] F}
(hg : Tendsto (fun n x => f n x) atTop (𝓝 g)) (hf : CauchySeq f) : Tendsto f atTop (𝓝 g) := by |
/- Since `f` is a Cauchy sequence, there exists `b → 0` such that `‖f n - f m‖ ≤ b N` for any
`m, n ≥ N`. -/
rcases cauchySeq_iff_le_tendsto_0.1 hf with ⟨b, hb₀, hfb, hb_lim⟩
-- Since `b → 0`, it suffices to show that `‖f n x - g x‖ ≤ b n * ‖x‖` for all `n` and `x`.
suffices ∀ n x, ‖f n x - g x‖ ≤ b n * ‖x‖ from
tendsto_iff_norm_sub_tendsto_zero.2
(squeeze_zero (fun n => norm_nonneg _) (fun n => opNorm_le_bound _ (hb₀ n) (this n)) hb_lim)
intro n x
-- Note that `f m x → g x`, hence `‖f n x - f m x‖ → ‖f n x - g x‖` as `m → ∞`
have : Tendsto (fun m => ‖f n x - f m x‖) atTop (𝓝 ‖f n x - g x‖) :=
(tendsto_const_nhds.sub <| tendsto_pi_nhds.1 hg _).norm
-- Thus it suffices to verify `‖f n x - f m x‖ ≤ b n * ‖x‖` for `m ≥ n`.
refine le_of_tendsto this (eventually_atTop.2 ⟨n, fun m hm => ?_⟩)
-- This inequality follows from `‖f n - f m‖ ≤ b n`.
exact (f n - f m).le_of_opNorm_le (hfb _ _ _ le_rfl hm) _
| 0 |
import Mathlib.Algebra.Polynomial.Div
import Mathlib.RingTheory.Polynomial.Basic
import Mathlib.RingTheory.Ideal.QuotientOperations
#align_import ring_theory.polynomial.quotient from "leanprover-community/mathlib"@"4f840b8d28320b20c87db17b3a6eef3d325fca87"
set_option linter.uppercaseLean3 false
open Polynomial
namespace Ideal
noncomputable section
open Polynomial
variable {R : Type*} [CommRing R]
theorem quotient_map_C_eq_zero {I : Ideal R} :
∀ a ∈ I, ((Quotient.mk (map (C : R →+* R[X]) I : Ideal R[X])).comp C) a = 0 := by
intro a ha
rw [RingHom.comp_apply, Quotient.eq_zero_iff_mem]
exact mem_map_of_mem _ ha
#align ideal.quotient_map_C_eq_zero Ideal.quotient_map_C_eq_zero
theorem eval₂_C_mk_eq_zero {I : Ideal R} :
∀ f ∈ (map (C : R →+* R[X]) I : Ideal R[X]), eval₂RingHom (C.comp (Quotient.mk I)) X f = 0 := by
intro a ha
rw [← sum_monomial_eq a]
dsimp
rw [eval₂_sum]
refine Finset.sum_eq_zero fun n _ => ?_
dsimp
rw [eval₂_monomial (C.comp (Quotient.mk I)) X]
refine mul_eq_zero_of_left (Polynomial.ext fun m => ?_) (X ^ n)
erw [coeff_C]
by_cases h : m = 0
· simpa [h] using Quotient.eq_zero_iff_mem.2 ((mem_map_C_iff.1 ha) n)
· simp [h]
#align ideal.eval₂_C_mk_eq_zero Ideal.eval₂_C_mk_eq_zero
def polynomialQuotientEquivQuotientPolynomial (I : Ideal R) :
(R ⧸ I)[X] ≃+* R[X] ⧸ (map C I : Ideal R[X]) where
toFun :=
eval₂RingHom
(Quotient.lift I ((Quotient.mk (map C I : Ideal R[X])).comp C) quotient_map_C_eq_zero)
(Quotient.mk (map C I : Ideal R[X]) X)
invFun :=
Quotient.lift (map C I : Ideal R[X]) (eval₂RingHom (C.comp (Quotient.mk I)) X)
eval₂_C_mk_eq_zero
map_mul' f g := by simp only [coe_eval₂RingHom, eval₂_mul]
map_add' f g := by simp only [eval₂_add, coe_eval₂RingHom]
left_inv := by
intro f
refine Polynomial.induction_on' f ?_ ?_
· intro p q hp hq
simp only [coe_eval₂RingHom] at hp hq
simp only [coe_eval₂RingHom, hp, hq, RingHom.map_add]
· rintro n ⟨x⟩
simp only [← smul_X_eq_monomial, C_mul', Quotient.lift_mk, Submodule.Quotient.quot_mk_eq_mk,
Quotient.mk_eq_mk, eval₂_X_pow, eval₂_smul, coe_eval₂RingHom, RingHom.map_pow, eval₂_C,
RingHom.coe_comp, RingHom.map_mul, eval₂_X, Function.comp_apply]
right_inv := by
rintro ⟨f⟩
refine Polynomial.induction_on' f ?_ ?_
· -- Porting note: was `simp_intro p q hp hq`
intros p q hp hq
simp only [Submodule.Quotient.quot_mk_eq_mk, Quotient.mk_eq_mk, map_add, Quotient.lift_mk,
coe_eval₂RingHom] at hp hq ⊢
rw [hp, hq]
· intro n a
simp only [← smul_X_eq_monomial, ← C_mul' a (X ^ n), Quotient.lift_mk,
Submodule.Quotient.quot_mk_eq_mk, Quotient.mk_eq_mk, eval₂_X_pow, eval₂_smul,
coe_eval₂RingHom, RingHom.map_pow, eval₂_C, RingHom.coe_comp, RingHom.map_mul, eval₂_X,
Function.comp_apply]
#align ideal.polynomial_quotient_equiv_quotient_polynomial Ideal.polynomialQuotientEquivQuotientPolynomial
@[simp]
theorem polynomialQuotientEquivQuotientPolynomial_symm_mk (I : Ideal R) (f : R[X]) :
I.polynomialQuotientEquivQuotientPolynomial.symm (Quotient.mk _ f) = f.map (Quotient.mk I) := by
rw [polynomialQuotientEquivQuotientPolynomial, RingEquiv.symm_mk, RingEquiv.coe_mk,
Equiv.coe_fn_mk, Quotient.lift_mk, coe_eval₂RingHom, eval₂_eq_eval_map, ← Polynomial.map_map,
← eval₂_eq_eval_map, Polynomial.eval₂_C_X]
#align ideal.polynomial_quotient_equiv_quotient_polynomial_symm_mk Ideal.polynomialQuotientEquivQuotientPolynomial_symm_mk
@[simp]
| Mathlib/RingTheory/Polynomial/Quotient.lean | 158 | 162 | theorem polynomialQuotientEquivQuotientPolynomial_map_mk (I : Ideal R) (f : R[X]) :
I.polynomialQuotientEquivQuotientPolynomial (f.map <| Quotient.mk I) =
Quotient.mk (map C I : Ideal R[X]) f := by |
apply (polynomialQuotientEquivQuotientPolynomial I).symm.injective
rw [RingEquiv.symm_apply_apply, polynomialQuotientEquivQuotientPolynomial_symm_mk]
| 0 |
import Mathlib.Data.List.Join
#align_import data.list.permutation from "leanprover-community/mathlib"@"dd71334db81d0bd444af1ee339a29298bef40734"
-- Make sure we don't import algebra
assert_not_exists Monoid
open Nat
variable {α β : Type*}
namespace List
theorem permutationsAux2_fst (t : α) (ts : List α) (r : List β) :
∀ (ys : List α) (f : List α → β), (permutationsAux2 t ts r ys f).1 = ys ++ ts
| [], f => rfl
| y :: ys, f => by simp [permutationsAux2, permutationsAux2_fst t _ _ ys]
#align list.permutations_aux2_fst List.permutationsAux2_fst
@[simp]
theorem permutationsAux2_snd_nil (t : α) (ts : List α) (r : List β) (f : List α → β) :
(permutationsAux2 t ts r [] f).2 = r :=
rfl
#align list.permutations_aux2_snd_nil List.permutationsAux2_snd_nil
@[simp]
theorem permutationsAux2_snd_cons (t : α) (ts : List α) (r : List β) (y : α) (ys : List α)
(f : List α → β) :
(permutationsAux2 t ts r (y :: ys) f).2 =
f (t :: y :: ys ++ ts) :: (permutationsAux2 t ts r ys fun x : List α => f (y :: x)).2 := by
simp [permutationsAux2, permutationsAux2_fst t _ _ ys]
#align list.permutations_aux2_snd_cons List.permutationsAux2_snd_cons
theorem permutationsAux2_append (t : α) (ts : List α) (r : List β) (ys : List α) (f : List α → β) :
(permutationsAux2 t ts nil ys f).2 ++ r = (permutationsAux2 t ts r ys f).2 := by
induction ys generalizing f <;> simp [*]
#align list.permutations_aux2_append List.permutationsAux2_append
theorem permutationsAux2_comp_append {t : α} {ts ys : List α} {r : List β} (f : List α → β) :
((permutationsAux2 t [] r ys) fun x => f (x ++ ts)).2 = (permutationsAux2 t ts r ys f).2 := by
induction' ys with ys_hd _ ys_ih generalizing f
· simp
· simp [ys_ih fun xs => f (ys_hd :: xs)]
#align list.permutations_aux2_comp_append List.permutationsAux2_comp_append
| Mathlib/Data/List/Permutation.lean | 90 | 100 | theorem map_permutationsAux2' {α' β'} (g : α → α') (g' : β → β') (t : α) (ts ys : List α)
(r : List β) (f : List α → β) (f' : List α' → β') (H : ∀ a, g' (f a) = f' (map g a)) :
map g' (permutationsAux2 t ts r ys f).2 =
(permutationsAux2 (g t) (map g ts) (map g' r) (map g ys) f').2 := by |
induction' ys with ys_hd _ ys_ih generalizing f f'
· simp
· simp only [map, permutationsAux2_snd_cons, cons_append, cons.injEq]
rw [ys_ih, permutationsAux2_fst]
· refine ⟨?_, rfl⟩
simp only [← map_cons, ← map_append]; apply H
· intro a; apply H
| 0 |
import Mathlib.MeasureTheory.Integral.Periodic
import Mathlib.Data.ZMod.Quotient
#align_import measure_theory.group.add_circle from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982"
open Set Function Filter MeasureTheory MeasureTheory.Measure Metric
open scoped MeasureTheory Pointwise Topology ENNReal
namespace AddCircle
variable {T : ℝ} [hT : Fact (0 < T)]
theorem closedBall_ae_eq_ball {x : AddCircle T} {ε : ℝ} : closedBall x ε =ᵐ[volume] ball x ε := by
rcases le_or_lt ε 0 with hε | hε
· rw [ball_eq_empty.mpr hε, ae_eq_empty, volume_closedBall,
min_eq_right (by linarith [hT.out] : 2 * ε ≤ T), ENNReal.ofReal_eq_zero]
exact mul_nonpos_of_nonneg_of_nonpos zero_le_two hε
· suffices volume (closedBall x ε) ≤ volume (ball x ε) by
exact (ae_eq_of_subset_of_measure_ge ball_subset_closedBall this measurableSet_ball
(measure_ne_top _ _)).symm
have : Tendsto (fun δ => volume (closedBall x δ)) (𝓝[<] ε) (𝓝 <| volume (closedBall x ε)) := by
simp_rw [volume_closedBall]
refine ENNReal.tendsto_ofReal (Tendsto.min tendsto_const_nhds <| Tendsto.const_mul _ ?_)
convert (@monotone_id ℝ _).tendsto_nhdsWithin_Iio ε
simp
refine le_of_tendsto this (mem_nhdsWithin_Iio_iff_exists_Ioo_subset.mpr ⟨0, hε, fun r hr => ?_⟩)
exact measure_mono (closedBall_subset_ball hr.2)
#align add_circle.closed_ball_ae_eq_ball AddCircle.closedBall_ae_eq_ball
theorem isAddFundamentalDomain_of_ae_ball (I : Set <| AddCircle T) (u x : AddCircle T)
(hu : IsOfFinAddOrder u) (hI : I =ᵐ[volume] ball x (T / (2 * addOrderOf u))) :
IsAddFundamentalDomain (AddSubgroup.zmultiples u) I := by
set G := AddSubgroup.zmultiples u
set n := addOrderOf u
set B := ball x (T / (2 * n))
have hn : 1 ≤ (n : ℝ) := by norm_cast; linarith [hu.addOrderOf_pos]
refine IsAddFundamentalDomain.mk_of_measure_univ_le ?_ ?_ ?_ ?_
· -- `NullMeasurableSet I volume`
exact measurableSet_ball.nullMeasurableSet.congr hI.symm
· -- `∀ (g : G), g ≠ 0 → AEDisjoint volume (g +ᵥ I) I`
rintro ⟨g, hg⟩ hg'
replace hg' : g ≠ 0 := by simpa only [Ne, AddSubgroup.mk_eq_zero] using hg'
change AEDisjoint volume (g +ᵥ I) I
refine AEDisjoint.congr (Disjoint.aedisjoint ?_)
((quasiMeasurePreserving_add_left volume (-g)).vadd_ae_eq_of_ae_eq g hI) hI
have hBg : g +ᵥ B = ball (g + x) (T / (2 * n)) := by
rw [add_comm g x, ← singleton_add_ball _ x g, add_ball, thickening_singleton]
rw [hBg]
apply ball_disjoint_ball
rw [dist_eq_norm, add_sub_cancel_right, div_mul_eq_div_div, ← add_div, ← add_div,
add_self_div_two, div_le_iff' (by positivity : 0 < (n : ℝ)), ← nsmul_eq_mul]
refine (le_add_order_smul_norm_of_isOfFinAddOrder (hu.of_mem_zmultiples hg) hg').trans
(nsmul_le_nsmul_left (norm_nonneg g) ?_)
exact Nat.le_of_dvd (addOrderOf_pos_iff.mpr hu) (addOrderOf_dvd_of_mem_zmultiples hg)
· -- `∀ (g : G), QuasiMeasurePreserving (VAdd.vadd g) volume volume`
exact fun g => quasiMeasurePreserving_add_left (G := AddCircle T) volume g
· -- `volume univ ≤ ∑' (g : G), volume (g +ᵥ I)`
replace hI := hI.trans closedBall_ae_eq_ball.symm
haveI : Fintype G := @Fintype.ofFinite _ hu.finite_zmultiples.to_subtype
have hG_card : (Finset.univ : Finset G).card = n := by
show _ = addOrderOf u
rw [← Nat.card_zmultiples, Nat.card_eq_fintype_card]; rfl
simp_rw [measure_vadd]
rw [AddCircle.measure_univ, tsum_fintype, Finset.sum_const, measure_congr hI,
volume_closedBall, ← ENNReal.ofReal_nsmul, mul_div, mul_div_mul_comm,
div_self, one_mul, min_eq_right (div_le_self hT.out.le hn), hG_card,
nsmul_eq_mul, mul_div_cancel₀ T (lt_of_lt_of_le zero_lt_one hn).ne.symm]
exact two_ne_zero
#align add_circle.is_add_fundamental_domain_of_ae_ball AddCircle.isAddFundamentalDomain_of_ae_ball
| Mathlib/MeasureTheory/Group/AddCircle.lean | 95 | 104 | theorem volume_of_add_preimage_eq (s I : Set <| AddCircle T) (u x : AddCircle T)
(hu : IsOfFinAddOrder u) (hs : (u +ᵥ s : Set <| AddCircle T) =ᵐ[volume] s)
(hI : I =ᵐ[volume] ball x (T / (2 * addOrderOf u))) :
volume s = addOrderOf u • volume (s ∩ I) := by |
let G := AddSubgroup.zmultiples u
haveI : Fintype G := @Fintype.ofFinite _ hu.finite_zmultiples.to_subtype
have hsG : ∀ g : G, (g +ᵥ s : Set <| AddCircle T) =ᵐ[volume] s := by
rintro ⟨y, hy⟩; exact (vadd_ae_eq_self_of_mem_zmultiples hs hy : _)
rw [(isAddFundamentalDomain_of_ae_ball I u x hu hI).measure_eq_card_smul_of_vadd_ae_eq_self s hsG,
← Nat.card_zmultiples u]
| 0 |
import Mathlib.NumberTheory.ZetaValues
import Mathlib.NumberTheory.LSeries.RiemannZeta
open Complex Real Set
open scoped Nat
open HurwitzZeta
| Mathlib/NumberTheory/LSeries/HurwitzZetaValues.lean | 211 | 217 | theorem riemannZeta_two_mul_nat {k : ℕ} (hk : k ≠ 0) :
riemannZeta (2 * k) = (-1) ^ (k + 1) * (2 : ℂ) ^ (2 * k - 1)
* (π : ℂ) ^ (2 * k) * bernoulli (2 * k) / (2 * k)! := by |
convert congr_arg ((↑) : ℝ → ℂ) (hasSum_zeta_nat hk).tsum_eq
· rw [← Nat.cast_two, ← Nat.cast_mul, zeta_nat_eq_tsum_of_gt_one (by omega)]
simp only [push_cast]
· norm_cast
| 0 |
import Mathlib.FieldTheory.Separable
import Mathlib.RingTheory.IntegralDomain
import Mathlib.Algebra.CharP.Reduced
import Mathlib.Tactic.ApplyFun
#align_import field_theory.finite.basic from "leanprover-community/mathlib"@"12a85fac627bea918960da036049d611b1a3ee43"
variable {K : Type*} {R : Type*}
local notation "q" => Fintype.card K
open Finset
open scoped Polynomial
namespace FiniteField
section Polynomial
variable [CommRing R] [IsDomain R]
open Polynomial
theorem card_image_polynomial_eval [DecidableEq R] [Fintype R] {p : R[X]} (hp : 0 < p.degree) :
Fintype.card R ≤ natDegree p * (univ.image fun x => eval x p).card :=
Finset.card_le_mul_card_image _ _ (fun a _ =>
calc
_ = (p - C a).roots.toFinset.card :=
congr_arg card (by simp [Finset.ext_iff, ← mem_roots_sub_C hp])
_ ≤ Multiset.card (p - C a).roots := Multiset.toFinset_card_le _
_ ≤ _ := card_roots_sub_C' hp)
#align finite_field.card_image_polynomial_eval FiniteField.card_image_polynomial_eval
| Mathlib/FieldTheory/Finite/Basic.lean | 76 | 98 | theorem exists_root_sum_quadratic [Fintype R] {f g : R[X]} (hf2 : degree f = 2) (hg2 : degree g = 2)
(hR : Fintype.card R % 2 = 1) : ∃ a b, f.eval a + g.eval b = 0 :=
letI := Classical.decEq R
suffices ¬Disjoint (univ.image fun x : R => eval x f)
(univ.image fun x : R => eval x (-g)) by
simp only [disjoint_left, mem_image] at this
push_neg at this
rcases this with ⟨x, ⟨a, _, ha⟩, ⟨b, _, hb⟩⟩
exact ⟨a, b, by rw [ha, ← hb, eval_neg, neg_add_self]⟩
fun hd : Disjoint _ _ =>
lt_irrefl (2 * ((univ.image fun x : R => eval x f) ∪ univ.image fun x : R => eval x (-g)).card) <|
calc 2 * ((univ.image fun x : R => eval x f) ∪ univ.image fun x : R => eval x (-g)).card
≤ 2 * Fintype.card R := Nat.mul_le_mul_left _ (Finset.card_le_univ _)
_ = Fintype.card R + Fintype.card R := two_mul _
_ < natDegree f * (univ.image fun x : R => eval x f).card +
natDegree (-g) * (univ.image fun x : R => eval x (-g)).card :=
(add_lt_add_of_lt_of_le
(lt_of_le_of_ne (card_image_polynomial_eval (by rw [hf2]; decide))
(mt (congr_arg (· % 2)) (by simp [natDegree_eq_of_degree_eq_some hf2, hR])))
(card_image_polynomial_eval (by rw [degree_neg, hg2]; decide)))
_ = 2 * ((univ.image fun x : R => eval x f) ∪ univ.image fun x : R => eval x (-g)).card := by |
rw [card_union_of_disjoint hd];
simp [natDegree_eq_of_degree_eq_some hf2, natDegree_eq_of_degree_eq_some hg2, mul_add]
| 0 |
import Mathlib.LinearAlgebra.Span
import Mathlib.RingTheory.Ideal.IsPrimary
import Mathlib.RingTheory.Ideal.QuotientOperations
import Mathlib.RingTheory.Noetherian
#align_import ring_theory.ideal.associated_prime from "leanprover-community/mathlib"@"f0c8bf9245297a541f468be517f1bde6195105e9"
variable {R : Type*} [CommRing R] (I J : Ideal R) (M : Type*) [AddCommGroup M] [Module R M]
def IsAssociatedPrime : Prop :=
I.IsPrime ∧ ∃ x : M, I = (R ∙ x).annihilator
#align is_associated_prime IsAssociatedPrime
variable (R)
def associatedPrimes : Set (Ideal R) :=
{ I | IsAssociatedPrime I M }
#align associated_primes associatedPrimes
variable {I J M R}
variable {M' : Type*} [AddCommGroup M'] [Module R M'] (f : M →ₗ[R] M')
theorem AssociatePrimes.mem_iff : I ∈ associatedPrimes R M ↔ IsAssociatedPrime I M := Iff.rfl
#align associate_primes.mem_iff AssociatePrimes.mem_iff
theorem IsAssociatedPrime.isPrime (h : IsAssociatedPrime I M) : I.IsPrime := h.1
#align is_associated_prime.is_prime IsAssociatedPrime.isPrime
theorem IsAssociatedPrime.map_of_injective (h : IsAssociatedPrime I M) (hf : Function.Injective f) :
IsAssociatedPrime I M' := by
obtain ⟨x, rfl⟩ := h.2
refine ⟨h.1, ⟨f x, ?_⟩⟩
ext r
rw [Submodule.mem_annihilator_span_singleton, Submodule.mem_annihilator_span_singleton, ←
map_smul, ← f.map_zero, hf.eq_iff]
#align is_associated_prime.map_of_injective IsAssociatedPrime.map_of_injective
theorem LinearEquiv.isAssociatedPrime_iff (l : M ≃ₗ[R] M') :
IsAssociatedPrime I M ↔ IsAssociatedPrime I M' :=
⟨fun h => h.map_of_injective l l.injective,
fun h => h.map_of_injective l.symm l.symm.injective⟩
#align linear_equiv.is_associated_prime_iff LinearEquiv.isAssociatedPrime_iff
theorem not_isAssociatedPrime_of_subsingleton [Subsingleton M] : ¬IsAssociatedPrime I M := by
rintro ⟨hI, x, hx⟩
apply hI.ne_top
rwa [Subsingleton.elim x 0, Submodule.span_singleton_eq_bot.mpr rfl, Submodule.annihilator_bot]
at hx
#align not_is_associated_prime_of_subsingleton not_isAssociatedPrime_of_subsingleton
variable (R)
theorem exists_le_isAssociatedPrime_of_isNoetherianRing [H : IsNoetherianRing R] (x : M)
(hx : x ≠ 0) : ∃ P : Ideal R, IsAssociatedPrime P M ∧ (R ∙ x).annihilator ≤ P := by
have : (R ∙ x).annihilator ≠ ⊤ := by
rwa [Ne, Ideal.eq_top_iff_one, Submodule.mem_annihilator_span_singleton, one_smul]
obtain ⟨P, ⟨l, h₁, y, rfl⟩, h₃⟩ :=
set_has_maximal_iff_noetherian.mpr H
{ P | (R ∙ x).annihilator ≤ P ∧ P ≠ ⊤ ∧ ∃ y : M, P = (R ∙ y).annihilator }
⟨(R ∙ x).annihilator, rfl.le, this, x, rfl⟩
refine ⟨_, ⟨⟨h₁, ?_⟩, y, rfl⟩, l⟩
intro a b hab
rw [or_iff_not_imp_left]
intro ha
rw [Submodule.mem_annihilator_span_singleton] at ha hab
have H₁ : (R ∙ y).annihilator ≤ (R ∙ a • y).annihilator := by
intro c hc
rw [Submodule.mem_annihilator_span_singleton] at hc ⊢
rw [smul_comm, hc, smul_zero]
have H₂ : (Submodule.span R {a • y}).annihilator ≠ ⊤ := by
rwa [Ne, Submodule.annihilator_eq_top_iff, Submodule.span_singleton_eq_bot]
rwa [H₁.eq_of_not_lt (h₃ (R ∙ a • y).annihilator ⟨l.trans H₁, H₂, _, rfl⟩),
Submodule.mem_annihilator_span_singleton, smul_comm, smul_smul]
#align exists_le_is_associated_prime_of_is_noetherian_ring exists_le_isAssociatedPrime_of_isNoetherianRing
variable {R}
theorem associatedPrimes.subset_of_injective (hf : Function.Injective f) :
associatedPrimes R M ⊆ associatedPrimes R M' := fun _I h => h.map_of_injective f hf
#align associated_primes.subset_of_injective associatedPrimes.subset_of_injective
theorem LinearEquiv.AssociatedPrimes.eq (l : M ≃ₗ[R] M') :
associatedPrimes R M = associatedPrimes R M' :=
le_antisymm (associatedPrimes.subset_of_injective l l.injective)
(associatedPrimes.subset_of_injective l.symm l.symm.injective)
#align linear_equiv.associated_primes.eq LinearEquiv.AssociatedPrimes.eq
theorem associatedPrimes.eq_empty_of_subsingleton [Subsingleton M] : associatedPrimes R M = ∅ := by
ext; simp only [Set.mem_empty_iff_false, iff_false_iff];
apply not_isAssociatedPrime_of_subsingleton
#align associated_primes.eq_empty_of_subsingleton associatedPrimes.eq_empty_of_subsingleton
variable (R M)
theorem associatedPrimes.nonempty [IsNoetherianRing R] [Nontrivial M] :
(associatedPrimes R M).Nonempty := by
obtain ⟨x, hx⟩ := exists_ne (0 : M)
obtain ⟨P, hP, _⟩ := exists_le_isAssociatedPrime_of_isNoetherianRing R x hx
exact ⟨P, hP⟩
#align associated_primes.nonempty associatedPrimes.nonempty
| Mathlib/RingTheory/Ideal/AssociatedPrime.lean | 132 | 142 | theorem biUnion_associatedPrimes_eq_zero_divisors [IsNoetherianRing R] :
⋃ p ∈ associatedPrimes R M, p = { r : R | ∃ x : M, x ≠ 0 ∧ r • x = 0 } := by |
simp_rw [← Submodule.mem_annihilator_span_singleton]
refine subset_antisymm (Set.iUnion₂_subset ?_) ?_
· rintro _ ⟨h, x, ⟨⟩⟩ r h'
refine ⟨x, ne_of_eq_of_ne (one_smul R x).symm ?_, h'⟩
refine mt (Submodule.mem_annihilator_span_singleton _ _).mpr ?_
exact (Ideal.ne_top_iff_one _).mp h.ne_top
· intro r ⟨x, h, h'⟩
obtain ⟨P, hP, hx⟩ := exists_le_isAssociatedPrime_of_isNoetherianRing R x h
exact Set.mem_biUnion hP (hx h')
| 0 |
import Mathlib.Analysis.NormedSpace.OperatorNorm.NormedSpace
suppress_compilation
set_option linter.uppercaseLean3 false
open Metric
open scoped Classical NNReal Topology Uniformity
variable {𝕜 E : Type*} [NontriviallyNormedField 𝕜]
section SemiNormed
variable [SeminormedAddCommGroup E] [NormedSpace 𝕜 E]
namespace ContinuousLinearMap
section MultiplicationLinear
section SMulLinear
variable (𝕜) (𝕜' : Type*) [NormedField 𝕜']
variable [NormedAlgebra 𝕜 𝕜'] [NormedSpace 𝕜' E] [IsScalarTower 𝕜 𝕜' E]
def lsmul : 𝕜' →L[𝕜] E →L[𝕜] E :=
((Algebra.lsmul 𝕜 𝕜 E).toLinearMap : 𝕜' →ₗ[𝕜] E →ₗ[𝕜] E).mkContinuous₂ 1 fun c x => by
simpa only [one_mul] using norm_smul_le c x
#align continuous_linear_map.lsmul ContinuousLinearMap.lsmul
@[simp]
theorem lsmul_apply (c : 𝕜') (x : E) : lsmul 𝕜 𝕜' c x = c • x :=
rfl
#align continuous_linear_map.lsmul_apply ContinuousLinearMap.lsmul_apply
variable {𝕜'}
| Mathlib/Analysis/NormedSpace/OperatorNorm/Mul.lean | 226 | 231 | theorem norm_toSpanSingleton (x : E) : ‖toSpanSingleton 𝕜 x‖ = ‖x‖ := by |
refine opNorm_eq_of_bounds (norm_nonneg _) (fun x => ?_) fun N _ h => ?_
· rw [toSpanSingleton_apply, norm_smul, mul_comm]
· specialize h 1
rw [toSpanSingleton_apply, norm_smul, mul_comm] at h
exact (mul_le_mul_right (by simp)).mp h
| 0 |
import Mathlib.Data.Fintype.List
#align_import data.list.cycle from "leanprover-community/mathlib"@"7413128c3bcb3b0818e3e18720abc9ea3100fb49"
assert_not_exists MonoidWithZero
namespace List
variable {α : Type*} [DecidableEq α]
def nextOr : ∀ (_ : List α) (_ _ : α), α
| [], _, default => default
| [_], _, default => default
-- Handles the not-found and the wraparound case
| y :: z :: xs, x, default => if x = y then z else nextOr (z :: xs) x default
#align list.next_or List.nextOr
@[simp]
theorem nextOr_nil (x d : α) : nextOr [] x d = d :=
rfl
#align list.next_or_nil List.nextOr_nil
@[simp]
theorem nextOr_singleton (x y d : α) : nextOr [y] x d = d :=
rfl
#align list.next_or_singleton List.nextOr_singleton
@[simp]
theorem nextOr_self_cons_cons (xs : List α) (x y d : α) : nextOr (x :: y :: xs) x d = y :=
if_pos rfl
#align list.next_or_self_cons_cons List.nextOr_self_cons_cons
theorem nextOr_cons_of_ne (xs : List α) (y x d : α) (h : x ≠ y) :
nextOr (y :: xs) x d = nextOr xs x d := by
cases' xs with z zs
· rfl
· exact if_neg h
#align list.next_or_cons_of_ne List.nextOr_cons_of_ne
theorem nextOr_eq_nextOr_of_mem_of_ne (xs : List α) (x d d' : α) (x_mem : x ∈ xs)
(x_ne : x ≠ xs.getLast (ne_nil_of_mem x_mem)) : nextOr xs x d = nextOr xs x d' := by
induction' xs with y ys IH
· cases x_mem
cases' ys with z zs
· simp at x_mem x_ne
contradiction
by_cases h : x = y
· rw [h, nextOr_self_cons_cons, nextOr_self_cons_cons]
· rw [nextOr, nextOr, IH]
· simpa [h] using x_mem
· simpa using x_ne
#align list.next_or_eq_next_or_of_mem_of_ne List.nextOr_eq_nextOr_of_mem_of_ne
theorem mem_of_nextOr_ne {xs : List α} {x d : α} (h : nextOr xs x d ≠ d) : x ∈ xs := by
induction' xs with y ys IH
· simp at h
cases' ys with z zs
· simp at h
· by_cases hx : x = y
· simp [hx]
· rw [nextOr_cons_of_ne _ _ _ _ hx] at h
simpa [hx] using IH h
#align list.mem_of_next_or_ne List.mem_of_nextOr_ne
theorem nextOr_concat {xs : List α} {x : α} (d : α) (h : x ∉ xs) : nextOr (xs ++ [x]) x d = d := by
induction' xs with z zs IH
· simp
· obtain ⟨hz, hzs⟩ := not_or.mp (mt mem_cons.2 h)
rw [cons_append, nextOr_cons_of_ne _ _ _ _ hz, IH hzs]
#align list.next_or_concat List.nextOr_concat
theorem nextOr_mem {xs : List α} {x d : α} (hd : d ∈ xs) : nextOr xs x d ∈ xs := by
revert hd
suffices ∀ xs' : List α, (∀ x ∈ xs, x ∈ xs') → d ∈ xs' → nextOr xs x d ∈ xs' by
exact this xs fun _ => id
intro xs' hxs' hd
induction' xs with y ys ih
· exact hd
cases' ys with z zs
· exact hd
rw [nextOr]
split_ifs with h
· exact hxs' _ (mem_cons_of_mem _ (mem_cons_self _ _))
· exact ih fun _ h => hxs' _ (mem_cons_of_mem _ h)
#align list.next_or_mem List.nextOr_mem
def next (l : List α) (x : α) (h : x ∈ l) : α :=
nextOr l x (l.get ⟨0, length_pos_of_mem h⟩)
#align list.next List.next
def prev : ∀ l : List α, ∀ x ∈ l, α
| [], _, h => by simp at h
| [y], _, _ => y
| y :: z :: xs, x, h =>
if hx : x = y then getLast (z :: xs) (cons_ne_nil _ _)
else if x = z then y else prev (z :: xs) x (by simpa [hx] using h)
#align list.prev List.prev
variable (l : List α) (x : α)
@[simp]
theorem next_singleton (x y : α) (h : x ∈ [y]) : next [y] x h = y :=
rfl
#align list.next_singleton List.next_singleton
@[simp]
theorem prev_singleton (x y : α) (h : x ∈ [y]) : prev [y] x h = y :=
rfl
#align list.prev_singleton List.prev_singleton
theorem next_cons_cons_eq' (y z : α) (h : x ∈ y :: z :: l) (hx : x = y) :
next (y :: z :: l) x h = z := by rw [next, nextOr, if_pos hx]
#align list.next_cons_cons_eq' List.next_cons_cons_eq'
@[simp]
theorem next_cons_cons_eq (z : α) (h : x ∈ x :: z :: l) : next (x :: z :: l) x h = z :=
next_cons_cons_eq' l x x z h rfl
#align list.next_cons_cons_eq List.next_cons_cons_eq
| Mathlib/Data/List/Cycle.lean | 163 | 169 | theorem next_ne_head_ne_getLast (h : x ∈ l) (y : α) (h : x ∈ y :: l) (hy : x ≠ y)
(hx : x ≠ getLast (y :: l) (cons_ne_nil _ _)) :
next (y :: l) x h = next l x (by simpa [hy] using h) := by |
rw [next, next, nextOr_cons_of_ne _ _ _ _ hy, nextOr_eq_nextOr_of_mem_of_ne]
· rwa [getLast_cons] at hx
exact ne_nil_of_mem (by assumption)
· rwa [getLast_cons] at hx
| 0 |
import Mathlib.Analysis.Convex.Body
import Mathlib.Analysis.Convex.Measure
import Mathlib.MeasureTheory.Group.FundamentalDomain
#align_import measure_theory.group.geometry_of_numbers from "leanprover-community/mathlib"@"fd5edc43dc4f10b85abfe544b88f82cf13c5f844"
namespace MeasureTheory
open ENNReal FiniteDimensional MeasureTheory MeasureTheory.Measure Set Filter
open scoped Pointwise NNReal
variable {E L : Type*} [MeasurableSpace E] {μ : Measure E} {F s : Set E}
theorem exists_pair_mem_lattice_not_disjoint_vadd [AddCommGroup L] [Countable L] [AddAction L E]
[MeasurableSpace L] [MeasurableVAdd L E] [VAddInvariantMeasure L E μ]
(fund : IsAddFundamentalDomain L F μ) (hS : NullMeasurableSet s μ) (h : μ F < μ s) :
∃ x y : L, x ≠ y ∧ ¬Disjoint (x +ᵥ s) (y +ᵥ s) := by
contrapose! h
exact ((fund.measure_eq_tsum _).trans (measure_iUnion₀
(Pairwise.mono h fun i j hij => (hij.mono inf_le_left inf_le_left).aedisjoint)
fun _ => (hS.vadd _).inter fund.nullMeasurableSet).symm).trans_le
(measure_mono <| Set.iUnion_subset fun _ => Set.inter_subset_right)
#align measure_theory.exists_pair_mem_lattice_not_disjoint_vadd MeasureTheory.exists_pair_mem_lattice_not_disjoint_vadd
theorem exists_ne_zero_mem_lattice_of_measure_mul_two_pow_lt_measure [NormedAddCommGroup E]
[NormedSpace ℝ E] [BorelSpace E] [FiniteDimensional ℝ E] [IsAddHaarMeasure μ]
{L : AddSubgroup E} [Countable L] (fund : IsAddFundamentalDomain L F μ)
(h_symm : ∀ x ∈ s, -x ∈ s) (h_conv : Convex ℝ s) (h : μ F * 2 ^ finrank ℝ E < μ s) :
∃ x ≠ 0, ((x : L) : E) ∈ s := by
have h_vol : μ F < μ ((2⁻¹ : ℝ) • s) := by
rw [addHaar_smul_of_nonneg μ (by norm_num : 0 ≤ (2 : ℝ)⁻¹) s, ←
mul_lt_mul_right (pow_ne_zero (finrank ℝ E) (two_ne_zero' _)) (pow_ne_top two_ne_top),
mul_right_comm, ofReal_pow (by norm_num : 0 ≤ (2 : ℝ)⁻¹), ofReal_inv_of_pos zero_lt_two]
norm_num
rwa [← mul_pow, ENNReal.inv_mul_cancel two_ne_zero two_ne_top, one_pow, one_mul]
obtain ⟨x, y, hxy, h⟩ :=
exists_pair_mem_lattice_not_disjoint_vadd fund ((h_conv.smul _).nullMeasurableSet _) h_vol
obtain ⟨_, ⟨v, hv, rfl⟩, w, hw, hvw⟩ := Set.not_disjoint_iff.mp h
refine ⟨x - y, sub_ne_zero.2 hxy, ?_⟩
rw [Set.mem_inv_smul_set_iff₀ (two_ne_zero' ℝ)] at hv hw
simp_rw [AddSubgroup.vadd_def, vadd_eq_add, add_comm _ w, ← sub_eq_sub_iff_add_eq_add, ←
AddSubgroup.coe_sub] at hvw
rw [← hvw, ← inv_smul_smul₀ (two_ne_zero' ℝ) (_ - _), smul_sub, sub_eq_add_neg, smul_add]
refine h_conv hw (h_symm _ hv) ?_ ?_ ?_ <;> norm_num
#align measure_theory.exists_ne_zero_mem_lattice_of_measure_mul_two_pow_lt_measure MeasureTheory.exists_ne_zero_mem_lattice_of_measure_mul_two_pow_lt_measure
| Mathlib/MeasureTheory/Group/GeometryOfNumbers.lean | 92 | 142 | theorem exists_ne_zero_mem_lattice_of_measure_mul_two_pow_le_measure [NormedAddCommGroup E]
[NormedSpace ℝ E] [BorelSpace E] [FiniteDimensional ℝ E] [Nontrivial E] [IsAddHaarMeasure μ]
{L : AddSubgroup E} [Countable L] [DiscreteTopology L] (fund : IsAddFundamentalDomain L F μ)
(h_symm : ∀ x ∈ s, -x ∈ s) (h_conv : Convex ℝ s) (h_cpt : IsCompact s)
(h : μ F * 2 ^ finrank ℝ E ≤ μ s) :
∃ x ≠ 0, ((x : L) : E) ∈ s := by |
have h_mes : μ s ≠ 0 := by
intro hμ
suffices μ F = 0 from fund.measure_ne_zero (NeZero.ne μ) this
rw [hμ, le_zero_iff, mul_eq_zero] at h
exact h.resolve_right <| pow_ne_zero _ two_ne_zero
have h_nemp : s.Nonempty := nonempty_of_measure_ne_zero h_mes
let u : ℕ → ℝ≥0 := (exists_seq_strictAnti_tendsto 0).choose
let K : ConvexBody E := ⟨s, h_conv, h_cpt, h_nemp⟩
let S : ℕ → ConvexBody E := fun n => (1 + u n) • K
let Z : ℕ → Set E := fun n => (S n) ∩ (L \ {0})
-- The convex bodies `S n` have volume strictly larger than `μ s` and thus we can apply
-- `exists_ne_zero_mem_lattice_of_measure_mul_two_pow_lt_measure` to them and obtain that
-- `S n` contains a nonzero point of `L`. Since the intersection of the `S n` is equal to `s`,
-- it follows that `s` contains a nonzero point of `L`.
have h_zero : 0 ∈ K := K.zero_mem_of_symmetric h_symm
suffices Set.Nonempty (⋂ n, Z n) by
erw [← Set.iInter_inter, K.iInter_smul_eq_self h_zero] at this
· obtain ⟨x, hx⟩ := this
exact ⟨⟨x, by aesop⟩, by aesop⟩
· exact (exists_seq_strictAnti_tendsto (0:ℝ≥0)).choose_spec.2.2
have h_clos : IsClosed ((L : Set E) \ {0}) := by
rsuffices ⟨U, hU⟩ : ∃ U : Set E, IsOpen U ∧ U ∩ L = {0}
· rw [sdiff_eq_sdiff_iff_inf_eq_inf (z := U).mpr (by simp [Set.inter_comm .. ▸ hU.2, zero_mem])]
exact AddSubgroup.isClosed_of_discrete.sdiff hU.1
exact isOpen_inter_eq_singleton_of_mem_discrete (zero_mem L)
refine IsCompact.nonempty_iInter_of_sequence_nonempty_isCompact_isClosed Z (fun n => ?_)
(fun n => ?_) ((S 0).isCompact.inter_right h_clos) (fun n => (S n).isClosed.inter h_clos)
· refine Set.inter_subset_inter_left _ (SetLike.coe_subset_coe.mpr ?_)
refine ConvexBody.smul_le_of_le K h_zero ?_
rw [add_le_add_iff_left]
exact le_of_lt <| (exists_seq_strictAnti_tendsto (0:ℝ≥0)).choose_spec.1 (Nat.lt.base n)
· suffices μ F * 2 ^ finrank ℝ E < μ (S n : Set E) by
have h_symm' : ∀ x ∈ S n, -x ∈ S n := by
rintro _ ⟨y, hy, rfl⟩
exact ⟨-y, h_symm _ hy, by simp⟩
obtain ⟨x, hx_nz, hx_mem⟩ := exists_ne_zero_mem_lattice_of_measure_mul_two_pow_lt_measure
fund h_symm' (S n).convex this
exact ⟨x, hx_mem, by aesop⟩
refine lt_of_le_of_lt h ?_
rw [ConvexBody.coe_smul', NNReal.smul_def, addHaar_smul_of_nonneg _ (NNReal.coe_nonneg _)]
rw [show μ s < _ ↔ 1 * μ s < _ by rw [one_mul]]
refine (mul_lt_mul_right h_mes (ne_of_lt h_cpt.measure_lt_top)).mpr ?_
rw [ofReal_pow (NNReal.coe_nonneg _)]
refine one_lt_pow ?_ (ne_of_gt finrank_pos)
simp [(exists_seq_strictAnti_tendsto (0:ℝ≥0)).choose_spec.2.1 n]
| 0 |
import Mathlib.Algebra.BigOperators.NatAntidiagonal
import Mathlib.Algebra.Polynomial.RingDivision
#align_import data.polynomial.mirror from "leanprover-community/mathlib"@"2196ab363eb097c008d4497125e0dde23fb36db2"
namespace Polynomial
open Polynomial
section Semiring
variable {R : Type*} [Semiring R] (p q : R[X])
noncomputable def mirror :=
p.reverse * X ^ p.natTrailingDegree
#align polynomial.mirror Polynomial.mirror
@[simp]
theorem mirror_zero : (0 : R[X]).mirror = 0 := by simp [mirror]
#align polynomial.mirror_zero Polynomial.mirror_zero
theorem mirror_monomial (n : ℕ) (a : R) : (monomial n a).mirror = monomial n a := by
classical
by_cases ha : a = 0
· rw [ha, monomial_zero_right, mirror_zero]
· rw [mirror, reverse, natDegree_monomial n a, if_neg ha, natTrailingDegree_monomial ha, ←
C_mul_X_pow_eq_monomial, reflect_C_mul_X_pow, revAt_le (le_refl n), tsub_self, pow_zero,
mul_one]
#align polynomial.mirror_monomial Polynomial.mirror_monomial
theorem mirror_C (a : R) : (C a).mirror = C a :=
mirror_monomial 0 a
set_option linter.uppercaseLean3 false in
#align polynomial.mirror_C Polynomial.mirror_C
theorem mirror_X : X.mirror = (X : R[X]) :=
mirror_monomial 1 (1 : R)
set_option linter.uppercaseLean3 false in
#align polynomial.mirror_X Polynomial.mirror_X
theorem mirror_natDegree : p.mirror.natDegree = p.natDegree := by
by_cases hp : p = 0
· rw [hp, mirror_zero]
nontriviality R
rw [mirror, natDegree_mul', reverse_natDegree, natDegree_X_pow,
tsub_add_cancel_of_le p.natTrailingDegree_le_natDegree]
rwa [leadingCoeff_X_pow, mul_one, reverse_leadingCoeff, Ne, trailingCoeff_eq_zero]
#align polynomial.mirror_nat_degree Polynomial.mirror_natDegree
theorem mirror_natTrailingDegree : p.mirror.natTrailingDegree = p.natTrailingDegree := by
by_cases hp : p = 0
· rw [hp, mirror_zero]
· rw [mirror, natTrailingDegree_mul_X_pow ((mt reverse_eq_zero.mp) hp),
natTrailingDegree_reverse, zero_add]
#align polynomial.mirror_nat_trailing_degree Polynomial.mirror_natTrailingDegree
theorem coeff_mirror (n : ℕ) :
p.mirror.coeff n = p.coeff (revAt (p.natDegree + p.natTrailingDegree) n) := by
by_cases h2 : p.natDegree < n
· rw [coeff_eq_zero_of_natDegree_lt (by rwa [mirror_natDegree])]
by_cases h1 : n ≤ p.natDegree + p.natTrailingDegree
· rw [revAt_le h1, coeff_eq_zero_of_lt_natTrailingDegree]
exact (tsub_lt_iff_left h1).mpr (Nat.add_lt_add_right h2 _)
· rw [← revAtFun_eq, revAtFun, if_neg h1, coeff_eq_zero_of_natDegree_lt h2]
rw [not_lt] at h2
rw [revAt_le (h2.trans (Nat.le_add_right _ _))]
by_cases h3 : p.natTrailingDegree ≤ n
· rw [← tsub_add_eq_add_tsub h2, ← tsub_tsub_assoc h2 h3, mirror, coeff_mul_X_pow', if_pos h3,
coeff_reverse, revAt_le (tsub_le_self.trans h2)]
rw [not_le] at h3
rw [coeff_eq_zero_of_natDegree_lt (lt_tsub_iff_right.mpr (Nat.add_lt_add_left h3 _))]
exact coeff_eq_zero_of_lt_natTrailingDegree (by rwa [mirror_natTrailingDegree])
#align polynomial.coeff_mirror Polynomial.coeff_mirror
--TODO: Extract `Finset.sum_range_rev_at` lemma.
| Mathlib/Algebra/Polynomial/Mirror.lean | 101 | 120 | theorem mirror_eval_one : p.mirror.eval 1 = p.eval 1 := by |
simp_rw [eval_eq_sum_range, one_pow, mul_one, mirror_natDegree]
refine Finset.sum_bij_ne_zero ?_ ?_ ?_ ?_ ?_
· exact fun n _ _ => revAt (p.natDegree + p.natTrailingDegree) n
· intro n hn hp
rw [Finset.mem_range_succ_iff] at *
rw [revAt_le (hn.trans (Nat.le_add_right _ _))]
rw [tsub_le_iff_tsub_le, add_comm, add_tsub_cancel_right, ← mirror_natTrailingDegree]
exact natTrailingDegree_le_of_ne_zero hp
· exact fun n₁ _ _ _ _ _ h => by rw [← @revAt_invol _ n₁, h, revAt_invol]
· intro n hn hp
use revAt (p.natDegree + p.natTrailingDegree) n
refine ⟨?_, ?_, revAt_invol⟩
· rw [Finset.mem_range_succ_iff] at *
rw [revAt_le (hn.trans (Nat.le_add_right _ _))]
rw [tsub_le_iff_tsub_le, add_comm, add_tsub_cancel_right]
exact natTrailingDegree_le_of_ne_zero hp
· change p.mirror.coeff _ ≠ 0
rwa [coeff_mirror, revAt_invol]
· exact fun n _ _ => p.coeff_mirror n
| 0 |
import Mathlib.LinearAlgebra.Eigenspace.Basic
import Mathlib.FieldTheory.Minpoly.Field
#align_import linear_algebra.eigenspace.minpoly from "leanprover-community/mathlib"@"c3216069e5f9369e6be586ccbfcde2592b3cec92"
universe u v w
namespace Module
namespace End
open Polynomial FiniteDimensional
open scoped Polynomial
variable {K : Type v} {V : Type w} [Field K] [AddCommGroup V] [Module K V]
| Mathlib/LinearAlgebra/Eigenspace/Minpoly.lean | 32 | 43 | theorem eigenspace_aeval_polynomial_degree_1 (f : End K V) (q : K[X]) (hq : degree q = 1) :
eigenspace f (-q.coeff 0 / q.leadingCoeff) = LinearMap.ker (aeval f q) :=
calc
eigenspace f (-q.coeff 0 / q.leadingCoeff)
_ = LinearMap.ker (q.leadingCoeff • f - algebraMap K (End K V) (-q.coeff 0)) := by |
rw [eigenspace_div]
intro h
rw [leadingCoeff_eq_zero_iff_deg_eq_bot.1 h] at hq
cases hq
_ = LinearMap.ker (aeval f (C q.leadingCoeff * X + C (q.coeff 0))) := by
rw [C_mul', aeval_def]; simp [algebraMap, Algebra.toRingHom]
_ = LinearMap.ker (aeval f q) := by rwa [← eq_X_add_C_of_degree_eq_one]
| 0 |
import Mathlib.Algebra.Order.Ring.Nat
import Mathlib.Combinatorics.SetFamily.Compression.Down
import Mathlib.Order.UpperLower.Basic
import Mathlib.Data.Fintype.Powerset
#align_import combinatorics.set_family.harris_kleitman from "leanprover-community/mathlib"@"b363547b3113d350d053abdf2884e9850a56b205"
open Finset
variable {α : Type*} [DecidableEq α] {𝒜 ℬ : Finset (Finset α)} {s : Finset α} {a : α}
theorem IsLowerSet.nonMemberSubfamily (h : IsLowerSet (𝒜 : Set (Finset α))) :
IsLowerSet (𝒜.nonMemberSubfamily a : Set (Finset α)) := fun s t hts => by
simp_rw [mem_coe, mem_nonMemberSubfamily]
exact And.imp (h hts) (mt <| @hts _)
#align is_lower_set.non_member_subfamily IsLowerSet.nonMemberSubfamily
theorem IsLowerSet.memberSubfamily (h : IsLowerSet (𝒜 : Set (Finset α))) :
IsLowerSet (𝒜.memberSubfamily a : Set (Finset α)) := by
rintro s t hts
simp_rw [mem_coe, mem_memberSubfamily]
exact And.imp (h <| insert_subset_insert _ hts) (mt <| @hts _)
#align is_lower_set.member_subfamily IsLowerSet.memberSubfamily
theorem IsLowerSet.memberSubfamily_subset_nonMemberSubfamily (h : IsLowerSet (𝒜 : Set (Finset α))) :
𝒜.memberSubfamily a ⊆ 𝒜.nonMemberSubfamily a := fun s => by
rw [mem_memberSubfamily, mem_nonMemberSubfamily]
exact And.imp_left (h <| subset_insert _ _)
#align is_lower_set.member_subfamily_subset_non_member_subfamily IsLowerSet.memberSubfamily_subset_nonMemberSubfamily
| Mathlib/Combinatorics/SetFamily/HarrisKleitman.lean | 55 | 91 | theorem IsLowerSet.le_card_inter_finset' (h𝒜 : IsLowerSet (𝒜 : Set (Finset α)))
(hℬ : IsLowerSet (ℬ : Set (Finset α))) (h𝒜s : ∀ t ∈ 𝒜, t ⊆ s) (hℬs : ∀ t ∈ ℬ, t ⊆ s) :
𝒜.card * ℬ.card ≤ 2 ^ s.card * (𝒜 ∩ ℬ).card := by |
induction' s using Finset.induction with a s hs ih generalizing 𝒜 ℬ
· simp_rw [subset_empty, ← subset_singleton_iff', subset_singleton_iff] at h𝒜s hℬs
obtain rfl | rfl := h𝒜s
· simp only [card_empty, zero_mul, empty_inter, mul_zero, le_refl]
obtain rfl | rfl := hℬs
· simp only [card_empty, inter_empty, mul_zero, zero_mul, le_refl]
· simp only [card_empty, pow_zero, inter_singleton_of_mem, mem_singleton, card_singleton,
le_refl]
rw [card_insert_of_not_mem hs, ← card_memberSubfamily_add_card_nonMemberSubfamily a 𝒜, ←
card_memberSubfamily_add_card_nonMemberSubfamily a ℬ, add_mul, mul_add, mul_add,
add_comm (_ * _), add_add_add_comm]
refine
(add_le_add_right
(mul_add_mul_le_mul_add_mul
(card_le_card h𝒜.memberSubfamily_subset_nonMemberSubfamily) <|
card_le_card hℬ.memberSubfamily_subset_nonMemberSubfamily)
_).trans
?_
rw [← two_mul, pow_succ', mul_assoc]
have h₀ : ∀ 𝒞 : Finset (Finset α), (∀ t ∈ 𝒞, t ⊆ insert a s) →
∀ t ∈ 𝒞.nonMemberSubfamily a, t ⊆ s := by
rintro 𝒞 h𝒞 t ht
rw [mem_nonMemberSubfamily] at ht
exact (subset_insert_iff_of_not_mem ht.2).1 (h𝒞 _ ht.1)
have h₁ : ∀ 𝒞 : Finset (Finset α), (∀ t ∈ 𝒞, t ⊆ insert a s) →
∀ t ∈ 𝒞.memberSubfamily a, t ⊆ s := by
rintro 𝒞 h𝒞 t ht
rw [mem_memberSubfamily] at ht
exact (subset_insert_iff_of_not_mem ht.2).1 ((subset_insert _ _).trans <| h𝒞 _ ht.1)
refine mul_le_mul_left' ?_ _
refine (add_le_add (ih h𝒜.memberSubfamily hℬ.memberSubfamily (h₁ _ h𝒜s) <| h₁ _ hℬs) <|
ih h𝒜.nonMemberSubfamily hℬ.nonMemberSubfamily (h₀ _ h𝒜s) <| h₀ _ hℬs).trans_eq ?_
rw [← mul_add, ← memberSubfamily_inter, ← nonMemberSubfamily_inter,
card_memberSubfamily_add_card_nonMemberSubfamily]
| 0 |
import Mathlib.Algebra.Order.Group.Nat
import Mathlib.Data.List.Rotate
import Mathlib.GroupTheory.Perm.Support
#align_import group_theory.perm.list from "leanprover-community/mathlib"@"9003f28797c0664a49e4179487267c494477d853"
namespace List
variable {α β : Type*}
section FormPerm
variable [DecidableEq α] (l : List α)
open Equiv Equiv.Perm
def formPerm : Equiv.Perm α :=
(zipWith Equiv.swap l l.tail).prod
#align list.form_perm List.formPerm
@[simp]
theorem formPerm_nil : formPerm ([] : List α) = 1 :=
rfl
#align list.form_perm_nil List.formPerm_nil
@[simp]
theorem formPerm_singleton (x : α) : formPerm [x] = 1 :=
rfl
#align list.form_perm_singleton List.formPerm_singleton
@[simp]
theorem formPerm_cons_cons (x y : α) (l : List α) :
formPerm (x :: y :: l) = swap x y * formPerm (y :: l) :=
prod_cons
#align list.form_perm_cons_cons List.formPerm_cons_cons
theorem formPerm_pair (x y : α) : formPerm [x, y] = swap x y :=
rfl
#align list.form_perm_pair List.formPerm_pair
theorem mem_or_mem_of_zipWith_swap_prod_ne : ∀ {l l' : List α} {x : α},
(zipWith swap l l').prod x ≠ x → x ∈ l ∨ x ∈ l'
| [], _, _ => by simp
| _, [], _ => by simp
| a::l, b::l', x => fun hx ↦
if h : (zipWith swap l l').prod x = x then
(eq_or_eq_of_swap_apply_ne_self (by simpa [h] using hx)).imp
(by rintro rfl; exact .head _) (by rintro rfl; exact .head _)
else
(mem_or_mem_of_zipWith_swap_prod_ne h).imp (.tail _) (.tail _)
theorem zipWith_swap_prod_support' (l l' : List α) :
{ x | (zipWith swap l l').prod x ≠ x } ≤ l.toFinset ⊔ l'.toFinset := fun _ h ↦ by
simpa using mem_or_mem_of_zipWith_swap_prod_ne h
#align list.zip_with_swap_prod_support' List.zipWith_swap_prod_support'
theorem zipWith_swap_prod_support [Fintype α] (l l' : List α) :
(zipWith swap l l').prod.support ≤ l.toFinset ⊔ l'.toFinset := by
intro x hx
have hx' : x ∈ { x | (zipWith swap l l').prod x ≠ x } := by simpa using hx
simpa using zipWith_swap_prod_support' _ _ hx'
#align list.zip_with_swap_prod_support List.zipWith_swap_prod_support
theorem support_formPerm_le' : { x | formPerm l x ≠ x } ≤ l.toFinset := by
refine (zipWith_swap_prod_support' l l.tail).trans ?_
simpa [Finset.subset_iff] using tail_subset l
#align list.support_form_perm_le' List.support_formPerm_le'
theorem support_formPerm_le [Fintype α] : support (formPerm l) ≤ l.toFinset := by
intro x hx
have hx' : x ∈ { x | formPerm l x ≠ x } := by simpa using hx
simpa using support_formPerm_le' _ hx'
#align list.support_form_perm_le List.support_formPerm_le
variable {l} {x : α}
theorem mem_of_formPerm_apply_ne (h : l.formPerm x ≠ x) : x ∈ l := by
simpa [or_iff_left_of_imp mem_of_mem_tail] using mem_or_mem_of_zipWith_swap_prod_ne h
#align list.mem_of_form_perm_apply_ne List.mem_of_formPerm_apply_ne
theorem formPerm_apply_of_not_mem (h : x ∉ l) : formPerm l x = x :=
not_imp_comm.1 mem_of_formPerm_apply_ne h
#align list.form_perm_apply_of_not_mem List.formPerm_apply_of_not_mem
| Mathlib/GroupTheory/Perm/List.lean | 116 | 128 | theorem formPerm_apply_mem_of_mem (h : x ∈ l) : formPerm l x ∈ l := by |
cases' l with y l
· simp at h
induction' l with z l IH generalizing x y
· simpa using h
· by_cases hx : x ∈ z :: l
· rw [formPerm_cons_cons, mul_apply, swap_apply_def]
split_ifs
· simp [IH _ hx]
· simp
· simp [*]
· replace h : x = y := Or.resolve_right (mem_cons.1 h) hx
simp [formPerm_apply_of_not_mem hx, ← h]
| 0 |
import Mathlib.Algebra.Module.Zlattice.Basic
import Mathlib.NumberTheory.NumberField.Embeddings
import Mathlib.NumberTheory.NumberField.FractionalIdeal
#align_import number_theory.number_field.canonical_embedding from "leanprover-community/mathlib"@"60da01b41bbe4206f05d34fd70c8dd7498717a30"
variable (K : Type*) [Field K]
namespace NumberField.canonicalEmbedding
open NumberField
def _root_.NumberField.canonicalEmbedding : K →+* ((K →+* ℂ) → ℂ) := Pi.ringHom fun φ => φ
theorem _root_.NumberField.canonicalEmbedding_injective [NumberField K] :
Function.Injective (NumberField.canonicalEmbedding K) := RingHom.injective _
variable {K}
@[simp]
theorem apply_at (φ : K →+* ℂ) (x : K) : (NumberField.canonicalEmbedding K x) φ = φ x := rfl
open scoped ComplexConjugate
theorem conj_apply {x : ((K →+* ℂ) → ℂ)} (φ : K →+* ℂ)
(hx : x ∈ Submodule.span ℝ (Set.range (canonicalEmbedding K))) :
conj (x φ) = x (ComplexEmbedding.conjugate φ) := by
refine Submodule.span_induction hx ?_ ?_ (fun _ _ hx hy => ?_) (fun a _ hx => ?_)
· rintro _ ⟨x, rfl⟩
rw [apply_at, apply_at, ComplexEmbedding.conjugate_coe_eq]
· rw [Pi.zero_apply, Pi.zero_apply, map_zero]
· rw [Pi.add_apply, Pi.add_apply, map_add, hx, hy]
· rw [Pi.smul_apply, Complex.real_smul, map_mul, Complex.conj_ofReal]
exact congrArg ((a : ℂ) * ·) hx
theorem nnnorm_eq [NumberField K] (x : K) :
‖canonicalEmbedding K x‖₊ = Finset.univ.sup (fun φ : K →+* ℂ => ‖φ x‖₊) := by
simp_rw [Pi.nnnorm_def, apply_at]
theorem norm_le_iff [NumberField K] (x : K) (r : ℝ) :
‖canonicalEmbedding K x‖ ≤ r ↔ ∀ φ : K →+* ℂ, ‖φ x‖ ≤ r := by
obtain hr | hr := lt_or_le r 0
· obtain ⟨φ⟩ := (inferInstance : Nonempty (K →+* ℂ))
refine iff_of_false ?_ ?_
· exact (hr.trans_le (norm_nonneg _)).not_le
· exact fun h => hr.not_le (le_trans (norm_nonneg _) (h φ))
· lift r to NNReal using hr
simp_rw [← coe_nnnorm, nnnorm_eq, NNReal.coe_le_coe, Finset.sup_le_iff, Finset.mem_univ,
forall_true_left]
variable (K)
def integerLattice : Subring ((K →+* ℂ) → ℂ) :=
(RingHom.range (algebraMap (𝓞 K) K)).map (canonicalEmbedding K)
theorem integerLattice.inter_ball_finite [NumberField K] (r : ℝ) :
((integerLattice K : Set ((K →+* ℂ) → ℂ)) ∩ Metric.closedBall 0 r).Finite := by
obtain hr | _ := lt_or_le r 0
· simp [Metric.closedBall_eq_empty.2 hr]
· have heq : ∀ x, canonicalEmbedding K x ∈ Metric.closedBall 0 r ↔
∀ φ : K →+* ℂ, ‖φ x‖ ≤ r := by
intro x; rw [← norm_le_iff, mem_closedBall_zero_iff]
convert (Embeddings.finite_of_norm_le K ℂ r).image (canonicalEmbedding K)
ext; constructor
· rintro ⟨⟨_, ⟨x, rfl⟩, rfl⟩, hx⟩
exact ⟨x, ⟨SetLike.coe_mem x, fun φ => (heq _).mp hx φ⟩, rfl⟩
· rintro ⟨x, ⟨hx1, hx2⟩, rfl⟩
exact ⟨⟨x, ⟨⟨x, hx1⟩, rfl⟩, rfl⟩, (heq x).mpr hx2⟩
open Module Fintype FiniteDimensional
noncomputable def latticeBasis [NumberField K] :
Basis (Free.ChooseBasisIndex ℤ (𝓞 K)) ℂ ((K →+* ℂ) → ℂ) := by
classical
-- Let `B` be the canonical basis of `(K →+* ℂ) → ℂ`. We prove that the determinant of
-- the image by `canonicalEmbedding` of the integral basis of `K` is nonzero. This
-- will imply the result.
let B := Pi.basisFun ℂ (K →+* ℂ)
let e : (K →+* ℂ) ≃ Free.ChooseBasisIndex ℤ (𝓞 K) :=
equivOfCardEq ((Embeddings.card K ℂ).trans (finrank_eq_card_basis (integralBasis K)))
let M := B.toMatrix (fun i => canonicalEmbedding K (integralBasis K (e i)))
suffices M.det ≠ 0 by
rw [← isUnit_iff_ne_zero, ← Basis.det_apply, ← is_basis_iff_det] at this
refine basisOfLinearIndependentOfCardEqFinrank
((linearIndependent_equiv e.symm).mpr this.1) ?_
rw [← finrank_eq_card_chooseBasisIndex, RingOfIntegers.rank, finrank_fintype_fun_eq_card,
Embeddings.card]
-- In order to prove that the determinant is nonzero, we show that it is equal to the
-- square of the discriminant of the integral basis and thus it is not zero
let N := Algebra.embeddingsMatrixReindex ℚ ℂ (fun i => integralBasis K (e i))
RingHom.equivRatAlgHom
rw [show M = N.transpose by { ext:2; rfl }]
rw [Matrix.det_transpose, ← pow_ne_zero_iff two_ne_zero]
convert (map_ne_zero_iff _ (algebraMap ℚ ℂ).injective).mpr
(Algebra.discr_not_zero_of_basis ℚ (integralBasis K))
rw [← Algebra.discr_reindex ℚ (integralBasis K) e.symm]
exact (Algebra.discr_eq_det_embeddingsMatrixReindex_pow_two ℚ ℂ
(fun i => integralBasis K (e i)) RingHom.equivRatAlgHom).symm
@[simp]
| Mathlib/NumberTheory/NumberField/CanonicalEmbedding/Basic.lean | 139 | 142 | theorem latticeBasis_apply [NumberField K] (i : Free.ChooseBasisIndex ℤ (𝓞 K)) :
latticeBasis K i = (canonicalEmbedding K) (integralBasis K i) := by |
simp only [latticeBasis, integralBasis_apply, coe_basisOfLinearIndependentOfCardEqFinrank,
Function.comp_apply, Equiv.apply_symm_apply]
| 0 |
import Mathlib.Topology.PartialHomeomorph
import Mathlib.Topology.SeparatedMap
#align_import topology.is_locally_homeomorph from "leanprover-community/mathlib"@"e97cf15cd1aec9bd5c193b2ffac5a6dc9118912b"
open Topology
variable {X Y Z : Type*} [TopologicalSpace X] [TopologicalSpace Y] [TopologicalSpace Z] (g : Y → Z)
(f : X → Y) (s : Set X) (t : Set Y)
def IsLocalHomeomorphOn :=
∀ x ∈ s, ∃ e : PartialHomeomorph X Y, x ∈ e.source ∧ f = e
#align is_locally_homeomorph_on IsLocalHomeomorphOn
theorem isLocalHomeomorphOn_iff_openEmbedding_restrict {f : X → Y} :
IsLocalHomeomorphOn f s ↔ ∀ x ∈ s, ∃ U ∈ 𝓝 x, OpenEmbedding (U.restrict f) := by
refine ⟨fun h x hx ↦ ?_, fun h x hx ↦ ?_⟩
· obtain ⟨e, hxe, rfl⟩ := h x hx
exact ⟨e.source, e.open_source.mem_nhds hxe, e.openEmbedding_restrict⟩
· obtain ⟨U, hU, emb⟩ := h x hx
have : OpenEmbedding ((interior U).restrict f) := by
refine emb.comp ⟨embedding_inclusion interior_subset, ?_⟩
rw [Set.range_inclusion]; exact isOpen_induced isOpen_interior
obtain ⟨cont, inj, openMap⟩ := openEmbedding_iff_continuous_injective_open.mp this
haveI : Nonempty X := ⟨x⟩
exact ⟨PartialHomeomorph.ofContinuousOpenRestrict
(Set.injOn_iff_injective.mpr inj).toPartialEquiv
(continuousOn_iff_continuous_restrict.mpr cont) openMap isOpen_interior,
mem_interior_iff_mem_nhds.mpr hU, rfl⟩
namespace IsLocalHomeomorphOn
theorem mk (h : ∀ x ∈ s, ∃ e : PartialHomeomorph X Y, x ∈ e.source ∧ Set.EqOn f e e.source) :
IsLocalHomeomorphOn f s := by
intro x hx
obtain ⟨e, hx, he⟩ := h x hx
exact
⟨{ e with
toFun := f
map_source' := fun _x hx ↦ by rw [he hx]; exact e.map_source' hx
left_inv' := fun _x hx ↦ by rw [he hx]; exact e.left_inv' hx
right_inv' := fun _y hy ↦ by rw [he (e.map_target' hy)]; exact e.right_inv' hy
continuousOn_toFun := (continuousOn_congr he).mpr e.continuousOn_toFun },
hx, rfl⟩
#align is_locally_homeomorph_on.mk IsLocalHomeomorphOn.mk
lemma PartialHomeomorph.isLocalHomeomorphOn (e : PartialHomeomorph X Y) :
IsLocalHomeomorphOn e e.source :=
fun _ hx ↦ ⟨e, hx, rfl⟩
variable {g f s t}
theorem mono {t : Set X} (hf : IsLocalHomeomorphOn f t) (hst : s ⊆ t) : IsLocalHomeomorphOn f s :=
fun x hx ↦ hf x (hst hx)
| Mathlib/Topology/IsLocalHomeomorph.lean | 90 | 99 | theorem of_comp_left (hgf : IsLocalHomeomorphOn (g ∘ f) s) (hg : IsLocalHomeomorphOn g (f '' s))
(cont : ∀ x ∈ s, ContinuousAt f x) : IsLocalHomeomorphOn f s := mk f s fun x hx ↦ by
obtain ⟨g, hxg, rfl⟩ := hg (f x) ⟨x, hx, rfl⟩
obtain ⟨gf, hgf, he⟩ := hgf x hx
refine ⟨(gf.restr <| f ⁻¹' g.source).trans g.symm, ⟨⟨hgf, mem_interior_iff_mem_nhds.mpr
((cont x hx).preimage_mem_nhds <| g.open_source.mem_nhds hxg)⟩, he ▸ g.map_source hxg⟩,
fun y hy ↦ ?_⟩
change f y = g.symm (gf y)
have : f y ∈ g.source := by | apply interior_subset hy.1.2
rw [← he, g.eq_symm_apply this (by apply g.map_source this), Function.comp_apply]
| 0 |
import Mathlib.MeasureTheory.MeasurableSpace.Defs
import Mathlib.SetTheory.Cardinal.Cofinality
import Mathlib.SetTheory.Cardinal.Continuum
#align_import measure_theory.card_measurable_space from "leanprover-community/mathlib"@"f2b108e8e97ba393f22bf794989984ddcc1da89b"
universe u
variable {α : Type u}
open Cardinal Set
-- Porting note: fix universe below, not here
local notation "ω₁" => (WellOrder.α <| Quotient.out <| Cardinal.ord (aleph 1 : Cardinal))
namespace MeasurableSpace
def generateMeasurableRec (s : Set (Set α)) : (ω₁ : Type u) → Set (Set α)
| i =>
let S := ⋃ j : Iio i, generateMeasurableRec s (j.1)
s ∪ {∅} ∪ compl '' S ∪ Set.range fun f : ℕ → S => ⋃ n, (f n).1
termination_by i => i
decreasing_by exact j.2
#align measurable_space.generate_measurable_rec MeasurableSpace.generateMeasurableRec
theorem self_subset_generateMeasurableRec (s : Set (Set α)) (i : ω₁) :
s ⊆ generateMeasurableRec s i := by
unfold generateMeasurableRec
apply_rules [subset_union_of_subset_left]
exact subset_rfl
#align measurable_space.self_subset_generate_measurable_rec MeasurableSpace.self_subset_generateMeasurableRec
theorem empty_mem_generateMeasurableRec (s : Set (Set α)) (i : ω₁) :
∅ ∈ generateMeasurableRec s i := by
unfold generateMeasurableRec
exact mem_union_left _ (mem_union_left _ (mem_union_right _ (mem_singleton ∅)))
#align measurable_space.empty_mem_generate_measurable_rec MeasurableSpace.empty_mem_generateMeasurableRec
theorem compl_mem_generateMeasurableRec {s : Set (Set α)} {i j : ω₁} (h : j < i) {t : Set α}
(ht : t ∈ generateMeasurableRec s j) : tᶜ ∈ generateMeasurableRec s i := by
unfold generateMeasurableRec
exact mem_union_left _ (mem_union_right _ ⟨t, mem_iUnion.2 ⟨⟨j, h⟩, ht⟩, rfl⟩)
#align measurable_space.compl_mem_generate_measurable_rec MeasurableSpace.compl_mem_generateMeasurableRec
theorem iUnion_mem_generateMeasurableRec {s : Set (Set α)} {i : ω₁} {f : ℕ → Set α}
(hf : ∀ n, ∃ j < i, f n ∈ generateMeasurableRec s j) :
(⋃ n, f n) ∈ generateMeasurableRec s i := by
unfold generateMeasurableRec
exact mem_union_right _ ⟨fun n => ⟨f n, let ⟨j, hj, hf⟩ := hf n; mem_iUnion.2 ⟨⟨j, hj⟩, hf⟩⟩, rfl⟩
#align measurable_space.Union_mem_generate_measurable_rec MeasurableSpace.iUnion_mem_generateMeasurableRec
theorem generateMeasurableRec_subset (s : Set (Set α)) {i j : ω₁} (h : i ≤ j) :
generateMeasurableRec s i ⊆ generateMeasurableRec s j := fun x hx => by
rcases eq_or_lt_of_le h with (rfl | h)
· exact hx
· convert iUnion_mem_generateMeasurableRec fun _ => ⟨i, h, hx⟩
exact (iUnion_const x).symm
#align measurable_space.generate_measurable_rec_subset MeasurableSpace.generateMeasurableRec_subset
| Mathlib/MeasureTheory/MeasurableSpace/Card.lean | 91 | 113 | theorem cardinal_generateMeasurableRec_le (s : Set (Set α)) (i : ω₁) :
#(generateMeasurableRec s i) ≤ max #s 2 ^ aleph0.{u} := by |
apply (aleph 1).ord.out.wo.wf.induction i
intro i IH
have A := aleph0_le_aleph 1
have B : aleph 1 ≤ max #s 2 ^ aleph0.{u} :=
aleph_one_le_continuum.trans (power_le_power_right (le_max_right _ _))
have C : ℵ₀ ≤ max #s 2 ^ aleph0.{u} := A.trans B
have J : #(⋃ j : Iio i, generateMeasurableRec s j.1) ≤ max #s 2 ^ aleph0.{u} := by
refine (mk_iUnion_le _).trans ?_
have D : ⨆ j : Iio i, #(generateMeasurableRec s j) ≤ _ := ciSup_le' fun ⟨j, hj⟩ => IH j hj
apply (mul_le_mul' ((mk_subtype_le _).trans (aleph 1).mk_ord_out.le) D).trans
rw [mul_eq_max A C]
exact max_le B le_rfl
rw [generateMeasurableRec]
apply_rules [(mk_union_le _ _).trans, add_le_of_le C, mk_image_le.trans]
· exact (le_max_left _ _).trans (self_le_power _ one_lt_aleph0.le)
· rw [mk_singleton]
exact one_lt_aleph0.le.trans C
· apply mk_range_le.trans
simp only [mk_pi, prod_const, lift_uzero, mk_denumerable, lift_aleph0]
have := @power_le_power_right _ _ ℵ₀ J
rwa [← power_mul, aleph0_mul_aleph0] at this
| 0 |
import Mathlib.Algebra.Group.Prod
import Mathlib.Data.Set.Lattice
#align_import data.nat.pairing from "leanprover-community/mathlib"@"207cfac9fcd06138865b5d04f7091e46d9320432"
assert_not_exists MonoidWithZero
open Prod Decidable Function
namespace Nat
-- Porting note: no pp_nodot
--@[pp_nodot]
def pair (a b : ℕ) : ℕ :=
if a < b then b * b + a else a * a + a + b
#align nat.mkpair Nat.pair
-- Porting note: no pp_nodot
--@[pp_nodot]
def unpair (n : ℕ) : ℕ × ℕ :=
let s := sqrt n
if n - s * s < s then (n - s * s, s) else (s, n - s * s - s)
#align nat.unpair Nat.unpair
@[simp]
| Mathlib/Data/Nat/Pairing.lean | 49 | 56 | theorem pair_unpair (n : ℕ) : pair (unpair n).1 (unpair n).2 = n := by |
dsimp only [unpair]; let s := sqrt n
have sm : s * s + (n - s * s) = n := Nat.add_sub_cancel' (sqrt_le _)
split_ifs with h
· simp [pair, h, sm]
· have hl : n - s * s - s ≤ s := Nat.sub_le_iff_le_add.2
(Nat.sub_le_iff_le_add'.2 <| by rw [← Nat.add_assoc]; apply sqrt_le_add)
simp [pair, hl.not_lt, Nat.add_assoc, Nat.add_sub_cancel' (le_of_not_gt h), sm]
| 0 |
import Mathlib.Algebra.BigOperators.Pi
import Mathlib.Algebra.BigOperators.Ring
import Mathlib.Algebra.Order.BigOperators.Ring.Finset
import Mathlib.Algebra.BigOperators.Fin
import Mathlib.Algebra.Group.Submonoid.Membership
import Mathlib.Data.Finsupp.Fin
import Mathlib.Data.Finsupp.Indicator
#align_import algebra.big_operators.finsupp from "leanprover-community/mathlib"@"842328d9df7e96fd90fc424e115679c15fb23a71"
noncomputable section
open Finset Function
variable {α ι γ A B C : Type*} [AddCommMonoid A] [AddCommMonoid B] [AddCommMonoid C]
variable {t : ι → A → C} (h0 : ∀ i, t i 0 = 0) (h1 : ∀ i x y, t i (x + y) = t i x + t i y)
variable {s : Finset α} {f : α → ι →₀ A} (i : ι)
variable (g : ι →₀ A) (k : ι → A → γ → B) (x : γ)
variable {β M M' N P G H R S : Type*}
namespace Finsupp
section SumProd
@[to_additive "`sum f g` is the sum of `g a (f a)` over the support of `f`. "]
def prod [Zero M] [CommMonoid N] (f : α →₀ M) (g : α → M → N) : N :=
∏ a ∈ f.support, g a (f a)
#align finsupp.prod Finsupp.prod
#align finsupp.sum Finsupp.sum
variable [Zero M] [Zero M'] [CommMonoid N]
@[to_additive]
theorem prod_of_support_subset (f : α →₀ M) {s : Finset α} (hs : f.support ⊆ s) (g : α → M → N)
(h : ∀ i ∈ s, g i 0 = 1) : f.prod g = ∏ x ∈ s, g x (f x) := by
refine Finset.prod_subset hs fun x hxs hx => h x hxs ▸ (congr_arg (g x) ?_)
exact not_mem_support_iff.1 hx
#align finsupp.prod_of_support_subset Finsupp.prod_of_support_subset
#align finsupp.sum_of_support_subset Finsupp.sum_of_support_subset
@[to_additive]
theorem prod_fintype [Fintype α] (f : α →₀ M) (g : α → M → N) (h : ∀ i, g i 0 = 1) :
f.prod g = ∏ i, g i (f i) :=
f.prod_of_support_subset (subset_univ _) g fun x _ => h x
#align finsupp.prod_fintype Finsupp.prod_fintype
#align finsupp.sum_fintype Finsupp.sum_fintype
@[to_additive (attr := simp)]
theorem prod_single_index {a : α} {b : M} {h : α → M → N} (h_zero : h a 0 = 1) :
(single a b).prod h = h a b :=
calc
(single a b).prod h = ∏ x ∈ {a}, h x (single a b x) :=
prod_of_support_subset _ support_single_subset h fun x hx =>
(mem_singleton.1 hx).symm ▸ h_zero
_ = h a b := by simp
#align finsupp.prod_single_index Finsupp.prod_single_index
#align finsupp.sum_single_index Finsupp.sum_single_index
@[to_additive]
theorem prod_mapRange_index {f : M → M'} {hf : f 0 = 0} {g : α →₀ M} {h : α → M' → N}
(h0 : ∀ a, h a 0 = 1) : (mapRange f hf g).prod h = g.prod fun a b => h a (f b) :=
Finset.prod_subset support_mapRange fun _ _ H => by rw [not_mem_support_iff.1 H, h0]
#align finsupp.prod_map_range_index Finsupp.prod_mapRange_index
#align finsupp.sum_map_range_index Finsupp.sum_mapRange_index
@[to_additive (attr := simp)]
theorem prod_zero_index {h : α → M → N} : (0 : α →₀ M).prod h = 1 :=
rfl
#align finsupp.prod_zero_index Finsupp.prod_zero_index
#align finsupp.sum_zero_index Finsupp.sum_zero_index
@[to_additive]
theorem prod_comm (f : α →₀ M) (g : β →₀ M') (h : α → M → β → M' → N) :
(f.prod fun x v => g.prod fun x' v' => h x v x' v') =
g.prod fun x' v' => f.prod fun x v => h x v x' v' :=
Finset.prod_comm
#align finsupp.prod_comm Finsupp.prod_comm
#align finsupp.sum_comm Finsupp.sum_comm
@[to_additive (attr := simp)]
theorem prod_ite_eq [DecidableEq α] (f : α →₀ M) (a : α) (b : α → M → N) :
(f.prod fun x v => ite (a = x) (b x v) 1) = ite (a ∈ f.support) (b a (f a)) 1 := by
dsimp [Finsupp.prod]
rw [f.support.prod_ite_eq]
#align finsupp.prod_ite_eq Finsupp.prod_ite_eq
#align finsupp.sum_ite_eq Finsupp.sum_ite_eq
-- @[simp]
| Mathlib/Algebra/BigOperators/Finsupp.lean | 115 | 119 | theorem sum_ite_self_eq [DecidableEq α] {N : Type*} [AddCommMonoid N] (f : α →₀ N) (a : α) :
(f.sum fun x v => ite (a = x) v 0) = f a := by |
classical
convert f.sum_ite_eq a fun _ => id
simp [ite_eq_right_iff.2 Eq.symm]
| 0 |
import Mathlib.Analysis.Normed.Group.Hom
import Mathlib.Analysis.Normed.Group.Completion
#align_import analysis.normed.group.hom_completion from "leanprover-community/mathlib"@"17ef379e997badd73e5eabb4d38f11919ab3c4b3"
noncomputable section
open Set NormedAddGroupHom UniformSpace
section Completion
variable {G : Type*} [SeminormedAddCommGroup G] {H : Type*} [SeminormedAddCommGroup H]
{K : Type*} [SeminormedAddCommGroup K]
def NormedAddGroupHom.completion (f : NormedAddGroupHom G H) :
NormedAddGroupHom (Completion G) (Completion H) :=
.ofLipschitz (f.toAddMonoidHom.completion f.continuous) f.lipschitz.completion_map
#align normed_add_group_hom.completion NormedAddGroupHom.completion
theorem NormedAddGroupHom.completion_def (f : NormedAddGroupHom G H) (x : Completion G) :
f.completion x = Completion.map f x :=
rfl
#align normed_add_group_hom.completion_def NormedAddGroupHom.completion_def
@[simp]
theorem NormedAddGroupHom.completion_coe_to_fun (f : NormedAddGroupHom G H) :
(f.completion : Completion G → Completion H) = Completion.map f := rfl
#align normed_add_group_hom.completion_coe_to_fun NormedAddGroupHom.completion_coe_to_fun
-- Porting note: `@[simp]` moved to the next lemma
theorem NormedAddGroupHom.completion_coe (f : NormedAddGroupHom G H) (g : G) :
f.completion g = f g :=
Completion.map_coe f.uniformContinuous _
#align normed_add_group_hom.completion_coe NormedAddGroupHom.completion_coe
@[simp]
theorem NormedAddGroupHom.completion_coe' (f : NormedAddGroupHom G H) (g : G) :
Completion.map f g = f g :=
f.completion_coe g
@[simps]
def normedAddGroupHomCompletionHom :
NormedAddGroupHom G H →+ NormedAddGroupHom (Completion G) (Completion H) where
toFun := NormedAddGroupHom.completion
map_zero' := toAddMonoidHom_injective AddMonoidHom.completion_zero
map_add' f g := toAddMonoidHom_injective <|
f.toAddMonoidHom.completion_add g.toAddMonoidHom f.continuous g.continuous
#align normed_add_group_hom_completion_hom normedAddGroupHomCompletionHom
#align normed_add_group_hom_completion_hom_apply normedAddGroupHomCompletionHom_apply
@[simp]
theorem NormedAddGroupHom.completion_id :
(NormedAddGroupHom.id G).completion = NormedAddGroupHom.id (Completion G) := by
ext x
rw [NormedAddGroupHom.completion_def, NormedAddGroupHom.coe_id, Completion.map_id]
rfl
#align normed_add_group_hom.completion_id NormedAddGroupHom.completion_id
theorem NormedAddGroupHom.completion_comp (f : NormedAddGroupHom G H) (g : NormedAddGroupHom H K) :
g.completion.comp f.completion = (g.comp f).completion := by
ext x
rw [NormedAddGroupHom.coe_comp, NormedAddGroupHom.completion_def,
NormedAddGroupHom.completion_coe_to_fun, NormedAddGroupHom.completion_coe_to_fun,
Completion.map_comp g.uniformContinuous f.uniformContinuous]
rfl
#align normed_add_group_hom.completion_comp NormedAddGroupHom.completion_comp
theorem NormedAddGroupHom.completion_neg (f : NormedAddGroupHom G H) :
(-f).completion = -f.completion :=
map_neg (normedAddGroupHomCompletionHom : NormedAddGroupHom G H →+ _) f
#align normed_add_group_hom.completion_neg NormedAddGroupHom.completion_neg
theorem NormedAddGroupHom.completion_add (f g : NormedAddGroupHom G H) :
(f + g).completion = f.completion + g.completion :=
normedAddGroupHomCompletionHom.map_add f g
#align normed_add_group_hom.completion_add NormedAddGroupHom.completion_add
theorem NormedAddGroupHom.completion_sub (f g : NormedAddGroupHom G H) :
(f - g).completion = f.completion - g.completion :=
map_sub (normedAddGroupHomCompletionHom : NormedAddGroupHom G H →+ _) f g
#align normed_add_group_hom.completion_sub NormedAddGroupHom.completion_sub
@[simp]
theorem NormedAddGroupHom.zero_completion : (0 : NormedAddGroupHom G H).completion = 0 :=
normedAddGroupHomCompletionHom.map_zero
#align normed_add_group_hom.zero_completion NormedAddGroupHom.zero_completion
@[simps] -- Porting note: added `@[simps]`
def NormedAddCommGroup.toCompl : NormedAddGroupHom G (Completion G) where
toFun := (↑)
map_add' := Completion.toCompl.map_add
bound' := ⟨1, by simp [le_refl]⟩
#align normed_add_comm_group.to_compl NormedAddCommGroup.toCompl
open NormedAddCommGroup
theorem NormedAddCommGroup.norm_toCompl (x : G) : ‖toCompl x‖ = ‖x‖ :=
Completion.norm_coe x
#align normed_add_comm_group.norm_to_compl NormedAddCommGroup.norm_toCompl
theorem NormedAddCommGroup.denseRange_toCompl : DenseRange (toCompl : G → Completion G) :=
Completion.denseInducing_coe.dense
#align normed_add_comm_group.dense_range_to_compl NormedAddCommGroup.denseRange_toCompl
@[simp]
theorem NormedAddGroupHom.completion_toCompl (f : NormedAddGroupHom G H) :
f.completion.comp toCompl = toCompl.comp f := by ext x; simp
#align normed_add_group_hom.completion_to_compl NormedAddGroupHom.completion_toCompl
@[simp]
theorem NormedAddGroupHom.norm_completion (f : NormedAddGroupHom G H) : ‖f.completion‖ = ‖f‖ :=
le_antisymm (ofLipschitz_norm_le _ _) <| opNorm_le_bound _ (norm_nonneg _) fun x => by
simpa using f.completion.le_opNorm x
#align normed_add_group_hom.norm_completion NormedAddGroupHom.norm_completion
| Mathlib/Analysis/Normed/Group/HomCompletion.lean | 165 | 168 | theorem NormedAddGroupHom.ker_le_ker_completion (f : NormedAddGroupHom G H) :
(toCompl.comp <| incl f.ker).range ≤ f.completion.ker := by |
rintro _ ⟨⟨g, h₀ : f g = 0⟩, rfl⟩
simp [h₀, mem_ker, Completion.coe_zero]
| 0 |
import Mathlib.Analysis.Complex.AbsMax
import Mathlib.Analysis.Asymptotics.SuperpolynomialDecay
#align_import analysis.complex.phragmen_lindelof from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982"
open Set Function Filter Asymptotics Metric Complex Bornology
open scoped Topology Filter Real
local notation "expR" => Real.exp
namespace PhragmenLindelof
variable {E : Type*} [NormedAddCommGroup E]
| Mathlib/Analysis/Complex/PhragmenLindelof.lean | 63 | 74 | theorem isBigO_sub_exp_exp {a : ℝ} {f g : ℂ → E} {l : Filter ℂ} {u : ℂ → ℝ}
(hBf : ∃ c < a, ∃ B, f =O[l] fun z => expR (B * expR (c * |u z|)))
(hBg : ∃ c < a, ∃ B, g =O[l] fun z => expR (B * expR (c * |u z|))) :
∃ c < a, ∃ B, (f - g) =O[l] fun z => expR (B * expR (c * |u z|)) := by |
have : ∀ {c₁ c₂ B₁ B₂}, c₁ ≤ c₂ → 0 ≤ B₂ → B₁ ≤ B₂ → ∀ z,
‖expR (B₁ * expR (c₁ * |u z|))‖ ≤ ‖expR (B₂ * expR (c₂ * |u z|))‖ := fun hc hB₀ hB z ↦ by
simp only [Real.norm_eq_abs, Real.abs_exp]; gcongr
rcases hBf with ⟨cf, hcf, Bf, hOf⟩; rcases hBg with ⟨cg, hcg, Bg, hOg⟩
refine ⟨max cf cg, max_lt hcf hcg, max 0 (max Bf Bg), ?_⟩
refine (hOf.trans_le <| this ?_ ?_ ?_).sub (hOg.trans_le <| this ?_ ?_ ?_)
exacts [le_max_left _ _, le_max_left _ _, (le_max_left _ _).trans (le_max_right _ _),
le_max_right _ _, le_max_left _ _, (le_max_right _ _).trans (le_max_right _ _)]
| 0 |
import Mathlib.RingTheory.FractionalIdeal.Basic
import Mathlib.RingTheory.Ideal.Norm
namespace FractionalIdeal
open scoped Pointwise nonZeroDivisors
variable {R : Type*} [CommRing R] [IsDedekindDomain R] [Module.Free ℤ R] [Module.Finite ℤ R]
variable {K : Type*} [CommRing K] [Algebra R K] [IsFractionRing R K]
theorem absNorm_div_norm_eq_absNorm_div_norm {I : FractionalIdeal R⁰ K} (a : R⁰) (I₀ : Ideal R)
(h : a • (I : Submodule R K) = Submodule.map (Algebra.linearMap R K) I₀) :
(Ideal.absNorm I.num : ℚ) / |Algebra.norm ℤ (I.den:R)| =
(Ideal.absNorm I₀ : ℚ) / |Algebra.norm ℤ (a:R)| := by
rw [div_eq_div_iff]
· replace h := congr_arg (I.den • ·) h
have h' := congr_arg (a • ·) (den_mul_self_eq_num I)
dsimp only at h h'
rw [smul_comm] at h
rw [h, Submonoid.smul_def, Submonoid.smul_def, ← Submodule.ideal_span_singleton_smul,
← Submodule.ideal_span_singleton_smul, ← Submodule.map_smul'', ← Submodule.map_smul'',
(LinearMap.map_injective ?_).eq_iff, smul_eq_mul, smul_eq_mul] at h'
· simp_rw [← Int.cast_natAbs, ← Nat.cast_mul, ← Ideal.absNorm_span_singleton]
rw [← _root_.map_mul, ← _root_.map_mul, mul_comm, ← h', mul_comm]
· exact LinearMap.ker_eq_bot.mpr (IsFractionRing.injective R K)
all_goals simpa [Algebra.norm_eq_zero_iff] using nonZeroDivisors.coe_ne_zero _
noncomputable def absNorm : FractionalIdeal R⁰ K →*₀ ℚ where
toFun I := (Ideal.absNorm I.num : ℚ) / |Algebra.norm ℤ (I.den : R)|
map_zero' := by
dsimp only
rw [num_zero_eq, Submodule.zero_eq_bot, Ideal.absNorm_bot, Nat.cast_zero, zero_div]
exact IsFractionRing.injective R K
map_one' := by
dsimp only
rw [absNorm_div_norm_eq_absNorm_div_norm 1 ⊤ (by simp [Submodule.one_eq_range]),
Ideal.absNorm_top, Nat.cast_one, OneMemClass.coe_one, _root_.map_one, abs_one, Int.cast_one,
one_div_one]
map_mul' I J := by
dsimp only
rw [absNorm_div_norm_eq_absNorm_div_norm (I.den * J.den) (I.num * J.num) (by
have : Algebra.linearMap R K = (IsScalarTower.toAlgHom R R K).toLinearMap := rfl
rw [coe_mul, this, Submodule.map_mul, ← this, ← den_mul_self_eq_num, ← den_mul_self_eq_num]
exact Submodule.mul_smul_mul_eq_smul_mul_smul _ _ _ _),
Submonoid.coe_mul, _root_.map_mul, _root_.map_mul, Nat.cast_mul, div_mul_div_comm,
Int.cast_abs, Int.cast_abs, Int.cast_abs, ← abs_mul, Int.cast_mul]
theorem absNorm_eq (I : FractionalIdeal R⁰ K) :
absNorm I = (Ideal.absNorm I.num : ℚ) / |Algebra.norm ℤ (I.den : R)| := rfl
theorem absNorm_eq' {I : FractionalIdeal R⁰ K} (a : R⁰) (I₀ : Ideal R)
(h : a • (I : Submodule R K) = Submodule.map (Algebra.linearMap R K) I₀) :
absNorm I = (Ideal.absNorm I₀ : ℚ) / |Algebra.norm ℤ (a:R)| := by
rw [absNorm, ← absNorm_div_norm_eq_absNorm_div_norm a I₀ h, MonoidWithZeroHom.coe_mk,
ZeroHom.coe_mk]
theorem absNorm_nonneg (I : FractionalIdeal R⁰ K) : 0 ≤ absNorm I := by dsimp [absNorm]; positivity
theorem absNorm_bot : absNorm (⊥ : FractionalIdeal R⁰ K) = 0 := absNorm.map_zero'
theorem absNorm_one : absNorm (1 : FractionalIdeal R⁰ K) = 1 := by convert absNorm.map_one'
theorem absNorm_eq_zero_iff [NoZeroDivisors K] {I : FractionalIdeal R⁰ K} :
absNorm I = 0 ↔ I = 0 := by
refine ⟨fun h ↦ zero_of_num_eq_bot zero_not_mem_nonZeroDivisors ?_, fun h ↦ h ▸ absNorm_bot⟩
rw [absNorm_eq, div_eq_zero_iff] at h
refine Ideal.absNorm_eq_zero_iff.mp <| Nat.cast_eq_zero.mp <| h.resolve_right ?_
simpa [Algebra.norm_eq_zero_iff] using nonZeroDivisors.coe_ne_zero _
| Mathlib/RingTheory/FractionalIdeal/Norm.lean | 97 | 100 | theorem coeIdeal_absNorm (I₀ : Ideal R) :
absNorm (I₀ : FractionalIdeal R⁰ K) = Ideal.absNorm I₀ := by |
rw [absNorm_eq' 1 I₀ (by rw [one_smul]; rfl), OneMemClass.coe_one, _root_.map_one, abs_one,
Int.cast_one, _root_.div_one]
| 0 |
import Mathlib.Algebra.CharP.Algebra
import Mathlib.Data.ZMod.Algebra
import Mathlib.FieldTheory.Finite.Basic
import Mathlib.FieldTheory.Galois
import Mathlib.FieldTheory.SplittingField.IsSplittingField
#align_import field_theory.finite.galois_field from "leanprover-community/mathlib"@"0723536a0522d24fc2f159a096fb3304bef77472"
noncomputable section
open Polynomial Finset
open scoped Polynomial
instance FiniteField.isSplittingField_sub (K F : Type*) [Field K] [Fintype K]
[Field F] [Algebra F K] : IsSplittingField F K (X ^ Fintype.card K - X) where
splits' := by
have h : (X ^ Fintype.card K - X : K[X]).natDegree = Fintype.card K :=
FiniteField.X_pow_card_sub_X_natDegree_eq K Fintype.one_lt_card
rw [← splits_id_iff_splits, splits_iff_card_roots, Polynomial.map_sub, Polynomial.map_pow,
map_X, h, FiniteField.roots_X_pow_card_sub_X K, ← Finset.card_def, Finset.card_univ]
adjoin_rootSet' := by
classical
trans Algebra.adjoin F ((roots (X ^ Fintype.card K - X : K[X])).toFinset : Set K)
· simp only [rootSet, aroots, Polynomial.map_pow, map_X, Polynomial.map_sub]
· rw [FiniteField.roots_X_pow_card_sub_X, val_toFinset, coe_univ, Algebra.adjoin_univ]
#align finite_field.has_sub.sub.polynomial.is_splitting_field FiniteField.isSplittingField_sub
| Mathlib/FieldTheory/Finite/GaloisField.lean | 55 | 60 | theorem galois_poly_separable {K : Type*} [Field K] (p q : ℕ) [CharP K p] (h : p ∣ q) :
Separable (X ^ q - X : K[X]) := by |
use 1, X ^ q - X - 1
rw [← CharP.cast_eq_zero_iff K[X] p] at h
rw [derivative_sub, derivative_X_pow, derivative_X, C_eq_natCast, h]
ring
| 0 |
import Mathlib.AlgebraicGeometry.PrimeSpectrum.Basic
import Mathlib.RingTheory.Polynomial.Basic
#align_import algebraic_geometry.prime_spectrum.is_open_comap_C from "leanprover-community/mathlib"@"052f6013363326d50cb99c6939814a4b8eb7b301"
open Ideal Polynomial PrimeSpectrum Set
namespace AlgebraicGeometry
namespace Polynomial
variable {R : Type*} [CommRing R] {f : R[X]}
set_option linter.uppercaseLean3 false
def imageOfDf (f : R[X]) : Set (PrimeSpectrum R) :=
{ p : PrimeSpectrum R | ∃ i : ℕ, coeff f i ∉ p.asIdeal }
#align algebraic_geometry.polynomial.image_of_Df AlgebraicGeometry.Polynomial.imageOfDf
theorem isOpen_imageOfDf : IsOpen (imageOfDf f) := by
rw [imageOfDf, setOf_exists fun i (x : PrimeSpectrum R) => coeff f i ∉ x.asIdeal]
exact isOpen_iUnion fun i => isOpen_basicOpen
#align algebraic_geometry.polynomial.is_open_image_of_Df AlgebraicGeometry.Polynomial.isOpen_imageOfDf
theorem comap_C_mem_imageOfDf {I : PrimeSpectrum R[X]}
(H : I ∈ (zeroLocus {f} : Set (PrimeSpectrum R[X]))ᶜ) :
PrimeSpectrum.comap (Polynomial.C : R →+* R[X]) I ∈ imageOfDf f :=
exists_C_coeff_not_mem (mem_compl_zeroLocus_iff_not_mem.mp H)
#align algebraic_geometry.polynomial.comap_C_mem_image_of_Df AlgebraicGeometry.Polynomial.comap_C_mem_imageOfDf
theorem imageOfDf_eq_comap_C_compl_zeroLocus :
imageOfDf f = PrimeSpectrum.comap (C : R →+* R[X]) '' (zeroLocus {f})ᶜ := by
ext x
refine ⟨fun hx => ⟨⟨map C x.asIdeal, isPrime_map_C_of_isPrime x.IsPrime⟩, ⟨?_, ?_⟩⟩, ?_⟩
· rw [mem_compl_iff, mem_zeroLocus, singleton_subset_iff]
cases' hx with i hi
exact fun a => hi (mem_map_C_iff.mp a i)
· ext x
refine ⟨fun h => ?_, fun h => subset_span (mem_image_of_mem C.1 h)⟩
rw [← @coeff_C_zero R x _]
exact mem_map_C_iff.mp h 0
· rintro ⟨xli, complement, rfl⟩
exact comap_C_mem_imageOfDf complement
#align algebraic_geometry.polynomial.image_of_Df_eq_comap_C_compl_zero_locus AlgebraicGeometry.Polynomial.imageOfDf_eq_comap_C_compl_zeroLocus
| Mathlib/AlgebraicGeometry/PrimeSpectrum/IsOpenComapC.lean | 74 | 79 | theorem isOpenMap_comap_C : IsOpenMap (PrimeSpectrum.comap (C : R →+* R[X])) := by |
rintro U ⟨s, z⟩
rw [← compl_compl U, ← z, ← iUnion_of_singleton_coe s, zeroLocus_iUnion, compl_iInter,
image_iUnion]
simp_rw [← imageOfDf_eq_comap_C_compl_zeroLocus]
exact isOpen_iUnion fun f => isOpen_imageOfDf
| 0 |
import Mathlib.Topology.ContinuousOn
import Mathlib.Order.Filter.SmallSets
#align_import topology.locally_finite from "leanprover-community/mathlib"@"55d771df074d0dd020139ee1cd4b95521422df9f"
-- locally finite family [General Topology (Bourbaki, 1995)]
open Set Function Filter Topology
variable {ι ι' α X Y : Type*} [TopologicalSpace X] [TopologicalSpace Y] {f g : ι → Set X}
def LocallyFinite (f : ι → Set X) :=
∀ x : X, ∃ t ∈ 𝓝 x, { i | (f i ∩ t).Nonempty }.Finite
#align locally_finite LocallyFinite
theorem locallyFinite_of_finite [Finite ι] (f : ι → Set X) : LocallyFinite f := fun _ =>
⟨univ, univ_mem, toFinite _⟩
#align locally_finite_of_finite locallyFinite_of_finite
namespace LocallyFinite
theorem point_finite (hf : LocallyFinite f) (x : X) : { b | x ∈ f b }.Finite :=
let ⟨_t, hxt, ht⟩ := hf x
ht.subset fun _b hb => ⟨x, hb, mem_of_mem_nhds hxt⟩
#align locally_finite.point_finite LocallyFinite.point_finite
protected theorem subset (hf : LocallyFinite f) (hg : ∀ i, g i ⊆ f i) : LocallyFinite g := fun a =>
let ⟨t, ht₁, ht₂⟩ := hf a
⟨t, ht₁, ht₂.subset fun i hi => hi.mono <| inter_subset_inter (hg i) Subset.rfl⟩
#align locally_finite.subset LocallyFinite.subset
theorem comp_injOn {g : ι' → ι} (hf : LocallyFinite f) (hg : InjOn g { i | (f (g i)).Nonempty }) :
LocallyFinite (f ∘ g) := fun x => by
let ⟨t, htx, htf⟩ := hf x
refine ⟨t, htx, htf.preimage <| ?_⟩
exact hg.mono fun i (hi : Set.Nonempty _) => hi.left
#align locally_finite.comp_inj_on LocallyFinite.comp_injOn
theorem comp_injective {g : ι' → ι} (hf : LocallyFinite f) (hg : Injective g) :
LocallyFinite (f ∘ g) :=
hf.comp_injOn hg.injOn
#align locally_finite.comp_injective LocallyFinite.comp_injective
theorem _root_.locallyFinite_iff_smallSets :
LocallyFinite f ↔ ∀ x, ∀ᶠ s in (𝓝 x).smallSets, { i | (f i ∩ s).Nonempty }.Finite :=
forall_congr' fun _ => Iff.symm <|
eventually_smallSets' fun _s _t hst ht =>
ht.subset fun _i hi => hi.mono <| inter_subset_inter_right _ hst
#align locally_finite_iff_small_sets locallyFinite_iff_smallSets
protected theorem eventually_smallSets (hf : LocallyFinite f) (x : X) :
∀ᶠ s in (𝓝 x).smallSets, { i | (f i ∩ s).Nonempty }.Finite :=
locallyFinite_iff_smallSets.mp hf x
#align locally_finite.eventually_small_sets LocallyFinite.eventually_smallSets
theorem exists_mem_basis {ι' : Sort*} (hf : LocallyFinite f) {p : ι' → Prop} {s : ι' → Set X}
{x : X} (hb : (𝓝 x).HasBasis p s) : ∃ i, p i ∧ { j | (f j ∩ s i).Nonempty }.Finite :=
let ⟨i, hpi, hi⟩ := hb.smallSets.eventually_iff.mp (hf.eventually_smallSets x)
⟨i, hpi, hi Subset.rfl⟩
#align locally_finite.exists_mem_basis LocallyFinite.exists_mem_basis
protected theorem nhdsWithin_iUnion (hf : LocallyFinite f) (a : X) :
𝓝[⋃ i, f i] a = ⨆ i, 𝓝[f i] a := by
rcases hf a with ⟨U, haU, hfin⟩
refine le_antisymm ?_ (Monotone.le_map_iSup fun _ _ ↦ nhdsWithin_mono _)
calc
𝓝[⋃ i, f i] a = 𝓝[⋃ i, f i ∩ U] a := by
rw [← iUnion_inter, ← nhdsWithin_inter_of_mem' (nhdsWithin_le_nhds haU)]
_ = 𝓝[⋃ i ∈ {j | (f j ∩ U).Nonempty}, (f i ∩ U)] a := by
simp only [mem_setOf_eq, iUnion_nonempty_self]
_ = ⨆ i ∈ {j | (f j ∩ U).Nonempty}, 𝓝[f i ∩ U] a := nhdsWithin_biUnion hfin _ _
_ ≤ ⨆ i, 𝓝[f i ∩ U] a := iSup₂_le_iSup _ _
_ ≤ ⨆ i, 𝓝[f i] a := iSup_mono fun i ↦ nhdsWithin_mono _ inter_subset_left
#align locally_finite.nhds_within_Union LocallyFinite.nhdsWithin_iUnion
| Mathlib/Topology/LocallyFinite.lean | 91 | 101 | theorem continuousOn_iUnion' {g : X → Y} (hf : LocallyFinite f)
(hc : ∀ i x, x ∈ closure (f i) → ContinuousWithinAt g (f i) x) :
ContinuousOn g (⋃ i, f i) := by |
rintro x -
rw [ContinuousWithinAt, hf.nhdsWithin_iUnion, tendsto_iSup]
intro i
by_cases hx : x ∈ closure (f i)
· exact hc i _ hx
· rw [mem_closure_iff_nhdsWithin_neBot, not_neBot] at hx
rw [hx]
exact tendsto_bot
| 0 |
import Mathlib.Analysis.Convex.Normed
import Mathlib.Analysis.NormedSpace.Connected
import Mathlib.LinearAlgebra.AffineSpace.ContinuousAffineEquiv
open Set
variable {F : Type*} [AddCommGroup F] [Module ℝ F] [TopologicalSpace F]
def AmpleSet (s : Set F) : Prop :=
∀ x ∈ s, convexHull ℝ (connectedComponentIn s x) = univ
@[simp]
theorem ampleSet_univ {F : Type*} [NormedAddCommGroup F] [NormedSpace ℝ F] :
AmpleSet (univ : Set F) := by
intro x _
rw [connectedComponentIn_univ, PreconnectedSpace.connectedComponent_eq_univ, convexHull_univ]
@[simp]
theorem ampleSet_empty : AmpleSet (∅ : Set F) := fun _ ↦ False.elim
namespace AmpleSet
| Mathlib/Analysis/Convex/AmpleSet.lean | 65 | 74 | theorem union {s t : Set F} (hs : AmpleSet s) (ht : AmpleSet t) : AmpleSet (s ∪ t) := by |
intro x hx
rcases hx with (h | h) <;>
-- The connected component of `x ∈ s` in `s ∪ t` contains the connected component of `x` in `s`,
-- hence is also full; similarly for `t`.
[have hx := hs x h; have hx := ht x h] <;>
rw [← Set.univ_subset_iff, ← hx] <;>
apply convexHull_mono <;>
apply connectedComponentIn_mono <;>
[apply subset_union_left; apply subset_union_right]
| 0 |
import Mathlib.Probability.Notation
import Mathlib.Probability.Integration
import Mathlib.MeasureTheory.Function.L2Space
#align_import probability.variance from "leanprover-community/mathlib"@"f0c8bf9245297a541f468be517f1bde6195105e9"
open MeasureTheory Filter Finset
noncomputable section
open scoped MeasureTheory ProbabilityTheory ENNReal NNReal
namespace ProbabilityTheory
-- Porting note: this lemma replaces `ENNReal.toReal_bit0`, which does not exist in Lean 4
private lemma coe_two : ENNReal.toReal 2 = (2 : ℝ) := rfl
-- Porting note: Consider if `evariance` or `eVariance` is better. Also,
-- consider `eVariationOn` in `Mathlib.Analysis.BoundedVariation`.
def evariance {Ω : Type*} {_ : MeasurableSpace Ω} (X : Ω → ℝ) (μ : Measure Ω) : ℝ≥0∞ :=
∫⁻ ω, (‖X ω - μ[X]‖₊ : ℝ≥0∞) ^ 2 ∂μ
#align probability_theory.evariance ProbabilityTheory.evariance
def variance {Ω : Type*} {_ : MeasurableSpace Ω} (X : Ω → ℝ) (μ : Measure Ω) : ℝ :=
(evariance X μ).toReal
#align probability_theory.variance ProbabilityTheory.variance
variable {Ω : Type*} {m : MeasurableSpace Ω} {X : Ω → ℝ} {μ : Measure Ω}
theorem _root_.MeasureTheory.Memℒp.evariance_lt_top [IsFiniteMeasure μ] (hX : Memℒp X 2 μ) :
evariance X μ < ∞ := by
have := ENNReal.pow_lt_top (hX.sub <| memℒp_const <| μ[X]).2 2
rw [snorm_eq_lintegral_rpow_nnnorm two_ne_zero ENNReal.two_ne_top, ← ENNReal.rpow_two] at this
simp only [coe_two, Pi.sub_apply, ENNReal.one_toReal, one_div] at this
rw [← ENNReal.rpow_mul, inv_mul_cancel (two_ne_zero : (2 : ℝ) ≠ 0), ENNReal.rpow_one] at this
simp_rw [ENNReal.rpow_two] at this
exact this
#align measure_theory.mem_ℒp.evariance_lt_top MeasureTheory.Memℒp.evariance_lt_top
theorem evariance_eq_top [IsFiniteMeasure μ] (hXm : AEStronglyMeasurable X μ) (hX : ¬Memℒp X 2 μ) :
evariance X μ = ∞ := by
by_contra h
rw [← Ne, ← lt_top_iff_ne_top] at h
have : Memℒp (fun ω => X ω - μ[X]) 2 μ := by
refine ⟨hXm.sub aestronglyMeasurable_const, ?_⟩
rw [snorm_eq_lintegral_rpow_nnnorm two_ne_zero ENNReal.two_ne_top]
simp only [coe_two, ENNReal.one_toReal, ENNReal.rpow_two, Ne]
exact ENNReal.rpow_lt_top_of_nonneg (by linarith) h.ne
refine hX ?_
-- Porting note: `μ[X]` without whitespace is ambiguous as it could be GetElem,
-- and `convert` cannot disambiguate based on typeclass inference failure.
convert this.add (memℒp_const <| μ [X])
ext ω
rw [Pi.add_apply, sub_add_cancel]
#align probability_theory.evariance_eq_top ProbabilityTheory.evariance_eq_top
| Mathlib/Probability/Variance.lean | 92 | 97 | theorem evariance_lt_top_iff_memℒp [IsFiniteMeasure μ] (hX : AEStronglyMeasurable X μ) :
evariance X μ < ∞ ↔ Memℒp X 2 μ := by |
refine ⟨?_, MeasureTheory.Memℒp.evariance_lt_top⟩
contrapose
rw [not_lt, top_le_iff]
exact evariance_eq_top hX
| 0 |
import Mathlib.Init.Data.Sigma.Lex
import Mathlib.Data.Prod.Lex
import Mathlib.Data.Sigma.Lex
import Mathlib.Order.Antichain
import Mathlib.Order.OrderIsoNat
import Mathlib.Order.WellFounded
import Mathlib.Tactic.TFAE
#align_import order.well_founded_set from "leanprover-community/mathlib"@"2c84c2c5496117349007d97104e7bbb471381592"
variable {ι α β γ : Type*} {π : ι → Type*}
namespace Set
def WellFoundedOn (s : Set α) (r : α → α → Prop) : Prop :=
WellFounded fun a b : s => r a b
#align set.well_founded_on Set.WellFoundedOn
@[simp]
theorem wellFoundedOn_empty (r : α → α → Prop) : WellFoundedOn ∅ r :=
wellFounded_of_isEmpty _
#align set.well_founded_on_empty Set.wellFoundedOn_empty
section WellFoundedOn
variable {r r' : α → α → Prop}
section AnyRel
variable {f : β → α} {s t : Set α} {x y : α}
theorem wellFoundedOn_iff :
s.WellFoundedOn r ↔ WellFounded fun a b : α => r a b ∧ a ∈ s ∧ b ∈ s := by
have f : RelEmbedding (fun (a : s) (b : s) => r a b) fun a b : α => r a b ∧ a ∈ s ∧ b ∈ s :=
⟨⟨(↑), Subtype.coe_injective⟩, by simp⟩
refine ⟨fun h => ?_, f.wellFounded⟩
rw [WellFounded.wellFounded_iff_has_min]
intro t ht
by_cases hst : (s ∩ t).Nonempty
· rw [← Subtype.preimage_coe_nonempty] at hst
rcases h.has_min (Subtype.val ⁻¹' t) hst with ⟨⟨m, ms⟩, mt, hm⟩
exact ⟨m, mt, fun x xt ⟨xm, xs, _⟩ => hm ⟨x, xs⟩ xt xm⟩
· rcases ht with ⟨m, mt⟩
exact ⟨m, mt, fun x _ ⟨_, _, ms⟩ => hst ⟨m, ⟨ms, mt⟩⟩⟩
#align set.well_founded_on_iff Set.wellFoundedOn_iff
@[simp]
theorem wellFoundedOn_univ : (univ : Set α).WellFoundedOn r ↔ WellFounded r := by
simp [wellFoundedOn_iff]
#align set.well_founded_on_univ Set.wellFoundedOn_univ
theorem _root_.WellFounded.wellFoundedOn : WellFounded r → s.WellFoundedOn r :=
InvImage.wf _
#align well_founded.well_founded_on WellFounded.wellFoundedOn
@[simp]
theorem wellFoundedOn_range : (range f).WellFoundedOn r ↔ WellFounded (r on f) := by
let f' : β → range f := fun c => ⟨f c, c, rfl⟩
refine ⟨fun h => (InvImage.wf f' h).mono fun c c' => id, fun h => ⟨?_⟩⟩
rintro ⟨_, c, rfl⟩
refine Acc.of_downward_closed f' ?_ _ ?_
· rintro _ ⟨_, c', rfl⟩ -
exact ⟨c', rfl⟩
· exact h.apply _
#align set.well_founded_on_range Set.wellFoundedOn_range
@[simp]
theorem wellFoundedOn_image {s : Set β} : (f '' s).WellFoundedOn r ↔ s.WellFoundedOn (r on f) := by
rw [image_eq_range]; exact wellFoundedOn_range
#align set.well_founded_on_image Set.wellFoundedOn_image
namespace WellFoundedOn
protected theorem induction (hs : s.WellFoundedOn r) (hx : x ∈ s) {P : α → Prop}
(hP : ∀ y ∈ s, (∀ z ∈ s, r z y → P z) → P y) : P x := by
let Q : s → Prop := fun y => P y
change Q ⟨x, hx⟩
refine WellFounded.induction hs ⟨x, hx⟩ ?_
simpa only [Subtype.forall]
#align set.well_founded_on.induction Set.WellFoundedOn.induction
protected theorem mono (h : t.WellFoundedOn r') (hle : r ≤ r') (hst : s ⊆ t) :
s.WellFoundedOn r := by
rw [wellFoundedOn_iff] at *
exact Subrelation.wf (fun xy => ⟨hle _ _ xy.1, hst xy.2.1, hst xy.2.2⟩) h
#align set.well_founded_on.mono Set.WellFoundedOn.mono
theorem mono' (h : ∀ (a) (_ : a ∈ s) (b) (_ : b ∈ s), r' a b → r a b) :
s.WellFoundedOn r → s.WellFoundedOn r' :=
Subrelation.wf @fun a b => h _ a.2 _ b.2
#align set.well_founded_on.mono' Set.WellFoundedOn.mono'
theorem subset (h : t.WellFoundedOn r) (hst : s ⊆ t) : s.WellFoundedOn r :=
h.mono le_rfl hst
#align set.well_founded_on.subset Set.WellFoundedOn.subset
open Relation
open List in
| Mathlib/Order/WellFoundedSet.lean | 146 | 161 | theorem acc_iff_wellFoundedOn {α} {r : α → α → Prop} {a : α} :
TFAE [Acc r a,
WellFoundedOn { b | ReflTransGen r b a } r,
WellFoundedOn { b | TransGen r b a } r] := by |
tfae_have 1 → 2
· refine fun h => ⟨fun b => InvImage.accessible _ ?_⟩
rw [← acc_transGen_iff] at h ⊢
obtain h' | h' := reflTransGen_iff_eq_or_transGen.1 b.2
· rwa [h'] at h
· exact h.inv h'
tfae_have 2 → 3
· exact fun h => h.subset fun _ => TransGen.to_reflTransGen
tfae_have 3 → 1
· refine fun h => Acc.intro _ (fun b hb => (h.apply ⟨b, .single hb⟩).of_fibration Subtype.val ?_)
exact fun ⟨c, hc⟩ d h => ⟨⟨d, .head h hc⟩, h, rfl⟩
tfae_finish
| 0 |
import Mathlib.Algebra.Order.Monoid.Canonical.Defs
import Mathlib.Data.List.Infix
import Mathlib.Data.List.MinMax
import Mathlib.Data.List.EditDistance.Defs
set_option autoImplicit true
variable {C : Levenshtein.Cost α β δ} [CanonicallyLinearOrderedAddCommMonoid δ]
theorem suffixLevenshtein_minimum_le_levenshtein_cons (xs : List α) (y ys) :
(suffixLevenshtein C xs ys).1.minimum ≤ levenshtein C xs (y :: ys) := by
induction xs with
| nil =>
simp only [suffixLevenshtein_nil', levenshtein_nil_cons,
List.minimum_singleton, WithTop.coe_le_coe]
exact le_add_of_nonneg_left (by simp)
| cons x xs ih =>
suffices
(suffixLevenshtein C (x :: xs) ys).1.minimum ≤ (C.delete x + levenshtein C xs (y :: ys)) ∧
(suffixLevenshtein C (x :: xs) ys).1.minimum ≤ (C.insert y + levenshtein C (x :: xs) ys) ∧
(suffixLevenshtein C (x :: xs) ys).1.minimum ≤ (C.substitute x y + levenshtein C xs ys) by
simpa [suffixLevenshtein_eq_tails_map]
refine ⟨?_, ?_, ?_⟩
· calc
_ ≤ (suffixLevenshtein C xs ys).1.minimum := by
simp [suffixLevenshtein_cons₁_fst, List.minimum_cons]
_ ≤ ↑(levenshtein C xs (y :: ys)) := ih
_ ≤ _ := by simp
· calc
(suffixLevenshtein C (x :: xs) ys).1.minimum ≤ (levenshtein C (x :: xs) ys) := by
simp [suffixLevenshtein_cons₁_fst, List.minimum_cons]
_ ≤ _ := by simp
· calc
(suffixLevenshtein C (x :: xs) ys).1.minimum ≤ (levenshtein C xs ys) := by
simp only [suffixLevenshtein_cons₁_fst, List.minimum_cons]
apply min_le_of_right_le
cases xs
· simp [suffixLevenshtein_nil']
· simp [suffixLevenshtein_cons₁, List.minimum_cons]
_ ≤ _ := by simp
theorem le_suffixLevenshtein_cons_minimum (xs : List α) (y ys) :
(suffixLevenshtein C xs ys).1.minimum ≤ (suffixLevenshtein C xs (y :: ys)).1.minimum := by
apply List.le_minimum_of_forall_le
simp only [suffixLevenshtein_eq_tails_map]
simp only [List.mem_map, List.mem_tails, forall_exists_index, and_imp, forall_apply_eq_imp_iff₂]
intro a suff
refine (?_ : _ ≤ _).trans (suffixLevenshtein_minimum_le_levenshtein_cons _ _ _)
simp only [suffixLevenshtein_eq_tails_map]
apply List.le_minimum_of_forall_le
intro b m
replace m : ∃ a_1, a_1 <:+ a ∧ levenshtein C a_1 ys = b := by simpa using m
obtain ⟨a', suff', rfl⟩ := m
apply List.minimum_le_of_mem'
simp only [List.mem_map, List.mem_tails]
suffices ∃ a, a <:+ xs ∧ levenshtein C a ys = levenshtein C a' ys by simpa
exact ⟨a', suff'.trans suff, rfl⟩
theorem le_suffixLevenshtein_append_minimum (xs : List α) (ys₁ ys₂) :
(suffixLevenshtein C xs ys₂).1.minimum ≤ (suffixLevenshtein C xs (ys₁ ++ ys₂)).1.minimum := by
induction ys₁ with
| nil => exact le_refl _
| cons y ys₁ ih => exact ih.trans (le_suffixLevenshtein_cons_minimum _ _ _)
| Mathlib/Data/List/EditDistance/Bounds.lean | 81 | 87 | theorem suffixLevenshtein_minimum_le_levenshtein_append (xs ys₁ ys₂) :
(suffixLevenshtein C xs ys₂).1.minimum ≤ levenshtein C xs (ys₁ ++ ys₂) := by |
cases ys₁ with
| nil => exact List.minimum_le_of_mem' (List.get_mem _ _ _)
| cons y ys₁ =>
exact (le_suffixLevenshtein_append_minimum _ _ _).trans
(suffixLevenshtein_minimum_le_levenshtein_cons _ _ _)
| 0 |
import Mathlib.Topology.Order.MonotoneContinuity
import Mathlib.Topology.Algebra.Order.LiminfLimsup
import Mathlib.Topology.Instances.NNReal
import Mathlib.Topology.EMetricSpace.Lipschitz
import Mathlib.Topology.Metrizable.Basic
import Mathlib.Topology.Order.T5
#align_import topology.instances.ennreal from "leanprover-community/mathlib"@"ec4b2eeb50364487f80421c0b4c41328a611f30d"
noncomputable section
open Set Filter Metric Function
open scoped Classical Topology ENNReal NNReal Filter
variable {α : Type*} {β : Type*} {γ : Type*}
namespace ENNReal
variable {a b c d : ℝ≥0∞} {r p q : ℝ≥0} {x y z : ℝ≥0∞} {ε ε₁ ε₂ : ℝ≥0∞} {s : Set ℝ≥0∞}
section TopologicalSpace
open TopologicalSpace
instance : TopologicalSpace ℝ≥0∞ := Preorder.topology ℝ≥0∞
instance : OrderTopology ℝ≥0∞ := ⟨rfl⟩
-- short-circuit type class inference
instance : T2Space ℝ≥0∞ := inferInstance
instance : T5Space ℝ≥0∞ := inferInstance
instance : T4Space ℝ≥0∞ := inferInstance
instance : SecondCountableTopology ℝ≥0∞ :=
orderIsoUnitIntervalBirational.toHomeomorph.embedding.secondCountableTopology
instance : MetrizableSpace ENNReal :=
orderIsoUnitIntervalBirational.toHomeomorph.embedding.metrizableSpace
theorem embedding_coe : Embedding ((↑) : ℝ≥0 → ℝ≥0∞) :=
coe_strictMono.embedding_of_ordConnected <| by rw [range_coe']; exact ordConnected_Iio
#align ennreal.embedding_coe ENNReal.embedding_coe
theorem isOpen_ne_top : IsOpen { a : ℝ≥0∞ | a ≠ ∞ } := isOpen_ne
#align ennreal.is_open_ne_top ENNReal.isOpen_ne_top
theorem isOpen_Ico_zero : IsOpen (Ico 0 b) := by
rw [ENNReal.Ico_eq_Iio]
exact isOpen_Iio
#align ennreal.is_open_Ico_zero ENNReal.isOpen_Ico_zero
theorem openEmbedding_coe : OpenEmbedding ((↑) : ℝ≥0 → ℝ≥0∞) :=
⟨embedding_coe, by rw [range_coe']; exact isOpen_Iio⟩
#align ennreal.open_embedding_coe ENNReal.openEmbedding_coe
theorem coe_range_mem_nhds : range ((↑) : ℝ≥0 → ℝ≥0∞) ∈ 𝓝 (r : ℝ≥0∞) :=
IsOpen.mem_nhds openEmbedding_coe.isOpen_range <| mem_range_self _
#align ennreal.coe_range_mem_nhds ENNReal.coe_range_mem_nhds
@[norm_cast]
theorem tendsto_coe {f : Filter α} {m : α → ℝ≥0} {a : ℝ≥0} :
Tendsto (fun a => (m a : ℝ≥0∞)) f (𝓝 ↑a) ↔ Tendsto m f (𝓝 a) :=
embedding_coe.tendsto_nhds_iff.symm
#align ennreal.tendsto_coe ENNReal.tendsto_coe
theorem continuous_coe : Continuous ((↑) : ℝ≥0 → ℝ≥0∞) :=
embedding_coe.continuous
#align ennreal.continuous_coe ENNReal.continuous_coe
theorem continuous_coe_iff {α} [TopologicalSpace α] {f : α → ℝ≥0} :
(Continuous fun a => (f a : ℝ≥0∞)) ↔ Continuous f :=
embedding_coe.continuous_iff.symm
#align ennreal.continuous_coe_iff ENNReal.continuous_coe_iff
theorem nhds_coe {r : ℝ≥0} : 𝓝 (r : ℝ≥0∞) = (𝓝 r).map (↑) :=
(openEmbedding_coe.map_nhds_eq r).symm
#align ennreal.nhds_coe ENNReal.nhds_coe
theorem tendsto_nhds_coe_iff {α : Type*} {l : Filter α} {x : ℝ≥0} {f : ℝ≥0∞ → α} :
Tendsto f (𝓝 ↑x) l ↔ Tendsto (f ∘ (↑) : ℝ≥0 → α) (𝓝 x) l := by
rw [nhds_coe, tendsto_map'_iff]
#align ennreal.tendsto_nhds_coe_iff ENNReal.tendsto_nhds_coe_iff
theorem continuousAt_coe_iff {α : Type*} [TopologicalSpace α] {x : ℝ≥0} {f : ℝ≥0∞ → α} :
ContinuousAt f ↑x ↔ ContinuousAt (f ∘ (↑) : ℝ≥0 → α) x :=
tendsto_nhds_coe_iff
#align ennreal.continuous_at_coe_iff ENNReal.continuousAt_coe_iff
theorem nhds_coe_coe {r p : ℝ≥0} :
𝓝 ((r : ℝ≥0∞), (p : ℝ≥0∞)) = (𝓝 (r, p)).map fun p : ℝ≥0 × ℝ≥0 => (↑p.1, ↑p.2) :=
((openEmbedding_coe.prod openEmbedding_coe).map_nhds_eq (r, p)).symm
#align ennreal.nhds_coe_coe ENNReal.nhds_coe_coe
theorem continuous_ofReal : Continuous ENNReal.ofReal :=
(continuous_coe_iff.2 continuous_id).comp continuous_real_toNNReal
#align ennreal.continuous_of_real ENNReal.continuous_ofReal
theorem tendsto_ofReal {f : Filter α} {m : α → ℝ} {a : ℝ} (h : Tendsto m f (𝓝 a)) :
Tendsto (fun a => ENNReal.ofReal (m a)) f (𝓝 (ENNReal.ofReal a)) :=
(continuous_ofReal.tendsto a).comp h
#align ennreal.tendsto_of_real ENNReal.tendsto_ofReal
theorem tendsto_toNNReal {a : ℝ≥0∞} (ha : a ≠ ∞) :
Tendsto ENNReal.toNNReal (𝓝 a) (𝓝 a.toNNReal) := by
lift a to ℝ≥0 using ha
rw [nhds_coe, tendsto_map'_iff]
exact tendsto_id
#align ennreal.tendsto_to_nnreal ENNReal.tendsto_toNNReal
| Mathlib/Topology/Instances/ENNReal.lean | 123 | 127 | theorem eventuallyEq_of_toReal_eventuallyEq {l : Filter α} {f g : α → ℝ≥0∞}
(hfi : ∀ᶠ x in l, f x ≠ ∞) (hgi : ∀ᶠ x in l, g x ≠ ∞)
(hfg : (fun x => (f x).toReal) =ᶠ[l] fun x => (g x).toReal) : f =ᶠ[l] g := by |
filter_upwards [hfi, hgi, hfg] with _ hfx hgx _
rwa [← ENNReal.toReal_eq_toReal hfx hgx]
| 0 |
import Mathlib.Init.Control.Combinators
import Mathlib.Data.Option.Defs
import Mathlib.Logic.IsEmpty
import Mathlib.Logic.Relator
import Mathlib.Util.CompileInductive
import Aesop
#align_import data.option.basic from "leanprover-community/mathlib"@"f340f229b1f461aa1c8ee11e0a172d0a3b301a4a"
universe u
namespace Option
variable {α β γ δ : Type*}
theorem coe_def : (fun a ↦ ↑a : α → Option α) = some :=
rfl
#align option.coe_def Option.coe_def
theorem mem_map {f : α → β} {y : β} {o : Option α} : y ∈ o.map f ↔ ∃ x ∈ o, f x = y := by simp
#align option.mem_map Option.mem_map
-- The simpNF linter says that the LHS can be simplified via `Option.mem_def`.
-- However this is a higher priority lemma.
-- https://github.com/leanprover/std4/issues/207
@[simp 1100, nolint simpNF]
theorem mem_map_of_injective {f : α → β} (H : Function.Injective f) {a : α} {o : Option α} :
f a ∈ o.map f ↔ a ∈ o := by
aesop
theorem forall_mem_map {f : α → β} {o : Option α} {p : β → Prop} :
(∀ y ∈ o.map f, p y) ↔ ∀ x ∈ o, p (f x) := by simp
#align option.forall_mem_map Option.forall_mem_map
theorem exists_mem_map {f : α → β} {o : Option α} {p : β → Prop} :
(∃ y ∈ o.map f, p y) ↔ ∃ x ∈ o, p (f x) := by simp
#align option.exists_mem_map Option.exists_mem_map
theorem coe_get {o : Option α} (h : o.isSome) : ((Option.get _ h : α) : Option α) = o :=
Option.some_get h
#align option.coe_get Option.coe_get
theorem eq_of_mem_of_mem {a : α} {o1 o2 : Option α} (h1 : a ∈ o1) (h2 : a ∈ o2) : o1 = o2 :=
h1.trans h2.symm
#align option.eq_of_mem_of_mem Option.eq_of_mem_of_mem
theorem Mem.leftUnique : Relator.LeftUnique ((· ∈ ·) : α → Option α → Prop) :=
fun _ _ _=> mem_unique
#align option.mem.left_unique Option.Mem.leftUnique
theorem some_injective (α : Type*) : Function.Injective (@some α) := fun _ _ ↦ some_inj.mp
#align option.some_injective Option.some_injective
theorem map_injective {f : α → β} (Hf : Function.Injective f) : Function.Injective (Option.map f)
| none, none, _ => rfl
| some a₁, some a₂, H => by rw [Hf (Option.some.inj H)]
#align option.map_injective Option.map_injective
@[simp]
theorem map_comp_some (f : α → β) : Option.map f ∘ some = some ∘ f :=
rfl
#align option.map_comp_some Option.map_comp_some
@[simp]
theorem none_bind' (f : α → Option β) : none.bind f = none :=
rfl
#align option.none_bind' Option.none_bind'
@[simp]
theorem some_bind' (a : α) (f : α → Option β) : (some a).bind f = f a :=
rfl
#align option.some_bind' Option.some_bind'
theorem bind_eq_some' {x : Option α} {f : α → Option β} {b : β} :
x.bind f = some b ↔ ∃ a, x = some a ∧ f a = some b := by
cases x <;> simp
#align option.bind_eq_some' Option.bind_eq_some'
#align option.bind_eq_none' Option.bind_eq_none'
theorem bind_congr {f g : α → Option β} {x : Option α}
(h : ∀ a ∈ x, f a = g a) : x.bind f = x.bind g := by
cases x <;> simp only [some_bind, none_bind, mem_def, h]
@[congr]
theorem bind_congr' {f g : α → Option β} {x y : Option α} (hx : x = y)
(hf : ∀ a ∈ y, f a = g a) : x.bind f = y.bind g :=
hx.symm ▸ bind_congr hf
theorem joinM_eq_join : joinM = @join α :=
funext fun _ ↦ rfl
#align option.join_eq_join Option.joinM_eq_join
theorem bind_eq_bind' {α β : Type u} {f : α → Option β} {x : Option α} : x >>= f = x.bind f :=
rfl
#align option.bind_eq_bind Option.bind_eq_bind'
theorem map_coe {α β} {a : α} {f : α → β} : f <$> (a : Option α) = ↑(f a) :=
rfl
#align option.map_coe Option.map_coe
@[simp]
theorem map_coe' {a : α} {f : α → β} : Option.map f (a : Option α) = ↑(f a) :=
rfl
#align option.map_coe' Option.map_coe'
theorem map_injective' : Function.Injective (@Option.map α β) := fun f g h ↦
funext fun x ↦ some_injective _ <| by simp only [← map_some', h]
#align option.map_injective' Option.map_injective'
@[simp]
theorem map_inj {f g : α → β} : Option.map f = Option.map g ↔ f = g :=
map_injective'.eq_iff
#align option.map_inj Option.map_inj
attribute [simp] map_id
@[simp]
theorem map_eq_id {f : α → α} : Option.map f = id ↔ f = id :=
map_injective'.eq_iff' map_id
#align option.map_eq_id Option.map_eq_id
theorem map_comm {f₁ : α → β} {f₂ : α → γ} {g₁ : β → δ} {g₂ : γ → δ} (h : g₁ ∘ f₁ = g₂ ∘ f₂)
(a : α) :
(Option.map f₁ a).map g₁ = (Option.map f₂ a).map g₂ := by rw [map_map, h, ← map_map]
#align option.map_comm Option.map_comm
section pmap
variable {p : α → Prop} (f : ∀ a : α, p a → β) (x : Option α)
-- Porting note: Can't simp tag this anymore because `pbind` simplifies
-- @[simp]
| Mathlib/Data/Option/Basic.lean | 162 | 163 | theorem pbind_eq_bind (f : α → Option β) (x : Option α) : (x.pbind fun a _ ↦ f a) = x.bind f := by |
cases x <;> simp only [pbind, none_bind', some_bind']
| 0 |
import Mathlib.Topology.Order.ExtendFrom
import Mathlib.Topology.Algebra.Order.Compact
import Mathlib.Topology.Order.LocalExtr
import Mathlib.Topology.Order.T5
#align_import analysis.calculus.local_extr from "leanprover-community/mathlib"@"3bce8d800a6f2b8f63fe1e588fd76a9ff4adcebe"
open Filter Set Topology
variable {X Y : Type*}
[ConditionallyCompleteLinearOrder X] [DenselyOrdered X] [TopologicalSpace X] [OrderTopology X]
[LinearOrder Y] [TopologicalSpace Y] [OrderTopology Y]
{f : X → Y} {a b : X} {l : Y}
| Mathlib/Topology/Algebra/Order/Rolle.lean | 37 | 55 | theorem exists_Ioo_extr_on_Icc (hab : a < b) (hfc : ContinuousOn f (Icc a b)) (hfI : f a = f b) :
∃ c ∈ Ioo a b, IsExtrOn f (Icc a b) c := by |
have ne : (Icc a b).Nonempty := nonempty_Icc.2 (le_of_lt hab)
-- Consider absolute min and max points
obtain ⟨c, cmem, cle⟩ : ∃ c ∈ Icc a b, ∀ x ∈ Icc a b, f c ≤ f x :=
isCompact_Icc.exists_isMinOn ne hfc
obtain ⟨C, Cmem, Cge⟩ : ∃ C ∈ Icc a b, ∀ x ∈ Icc a b, f x ≤ f C :=
isCompact_Icc.exists_isMaxOn ne hfc
by_cases hc : f c = f a
· by_cases hC : f C = f a
· have : ∀ x ∈ Icc a b, f x = f a := fun x hx => le_antisymm (hC ▸ Cge x hx) (hc ▸ cle x hx)
-- `f` is a constant, so we can take any point in `Ioo a b`
rcases nonempty_Ioo.2 hab with ⟨c', hc'⟩
refine ⟨c', hc', Or.inl fun x hx ↦ ?_⟩
simp only [mem_setOf_eq, this x hx, this c' (Ioo_subset_Icc_self hc'), le_rfl]
· refine ⟨C, ⟨lt_of_le_of_ne Cmem.1 <| mt ?_ hC, lt_of_le_of_ne Cmem.2 <| mt ?_ hC⟩, Or.inr Cge⟩
exacts [fun h => by rw [h], fun h => by rw [h, hfI]]
· refine ⟨c, ⟨lt_of_le_of_ne cmem.1 <| mt ?_ hc, lt_of_le_of_ne cmem.2 <| mt ?_ hc⟩, Or.inl cle⟩
exacts [fun h => by rw [h], fun h => by rw [h, hfI]]
| 0 |
import Mathlib.Algebra.GroupPower.IterateHom
import Mathlib.Algebra.Polynomial.Eval
import Mathlib.GroupTheory.GroupAction.Ring
#align_import data.polynomial.derivative from "leanprover-community/mathlib"@"bbeb185db4ccee8ed07dc48449414ebfa39cb821"
noncomputable section
open Finset
open Polynomial
namespace Polynomial
universe u v w y z
variable {R : Type u} {S : Type v} {T : Type w} {ι : Type y} {A : Type z} {a b : R} {n : ℕ}
section Derivative
section Semiring
variable [Semiring R]
def derivative : R[X] →ₗ[R] R[X] where
toFun p := p.sum fun n a => C (a * n) * X ^ (n - 1)
map_add' p q := by
dsimp only
rw [sum_add_index] <;>
simp only [add_mul, forall_const, RingHom.map_add, eq_self_iff_true, zero_mul,
RingHom.map_zero]
map_smul' a p := by
dsimp; rw [sum_smul_index] <;>
simp only [mul_sum, ← C_mul', mul_assoc, coeff_C_mul, RingHom.map_mul, forall_const, zero_mul,
RingHom.map_zero, sum]
#align polynomial.derivative Polynomial.derivative
theorem derivative_apply (p : R[X]) : derivative p = p.sum fun n a => C (a * n) * X ^ (n - 1) :=
rfl
#align polynomial.derivative_apply Polynomial.derivative_apply
theorem coeff_derivative (p : R[X]) (n : ℕ) :
coeff (derivative p) n = coeff p (n + 1) * (n + 1) := by
rw [derivative_apply]
simp only [coeff_X_pow, coeff_sum, coeff_C_mul]
rw [sum, Finset.sum_eq_single (n + 1)]
· simp only [Nat.add_succ_sub_one, add_zero, mul_one, if_true, eq_self_iff_true]; norm_cast
· intro b
cases b
· intros
rw [Nat.cast_zero, mul_zero, zero_mul]
· intro _ H
rw [Nat.add_one_sub_one, if_neg (mt (congr_arg Nat.succ) H.symm), mul_zero]
· rw [if_pos (add_tsub_cancel_right n 1).symm, mul_one, Nat.cast_add, Nat.cast_one,
mem_support_iff]
intro h
push_neg at h
simp [h]
#align polynomial.coeff_derivative Polynomial.coeff_derivative
-- Porting note (#10618): removed `simp`: `simp` can prove it.
theorem derivative_zero : derivative (0 : R[X]) = 0 :=
derivative.map_zero
#align polynomial.derivative_zero Polynomial.derivative_zero
theorem iterate_derivative_zero {k : ℕ} : derivative^[k] (0 : R[X]) = 0 :=
iterate_map_zero derivative k
#align polynomial.iterate_derivative_zero Polynomial.iterate_derivative_zero
@[simp]
| Mathlib/Algebra/Polynomial/Derivative.lean | 86 | 89 | theorem derivative_monomial (a : R) (n : ℕ) :
derivative (monomial n a) = monomial (n - 1) (a * n) := by |
rw [derivative_apply, sum_monomial_index, C_mul_X_pow_eq_monomial]
simp
| 0 |
import Mathlib.Algebra.Order.Floor
import Mathlib.Algebra.Order.Field.Power
import Mathlib.Data.Nat.Log
#align_import data.int.log from "leanprover-community/mathlib"@"1f0096e6caa61e9c849ec2adbd227e960e9dff58"
variable {R : Type*} [LinearOrderedSemifield R] [FloorSemiring R]
namespace Int
def log (b : ℕ) (r : R) : ℤ :=
if 1 ≤ r then Nat.log b ⌊r⌋₊ else -Nat.clog b ⌈r⁻¹⌉₊
#align int.log Int.log
theorem log_of_one_le_right (b : ℕ) {r : R} (hr : 1 ≤ r) : log b r = Nat.log b ⌊r⌋₊ :=
if_pos hr
#align int.log_of_one_le_right Int.log_of_one_le_right
theorem log_of_right_le_one (b : ℕ) {r : R} (hr : r ≤ 1) : log b r = -Nat.clog b ⌈r⁻¹⌉₊ := by
obtain rfl | hr := hr.eq_or_lt
· rw [log, if_pos hr, inv_one, Nat.ceil_one, Nat.floor_one, Nat.log_one_right, Nat.clog_one_right,
Int.ofNat_zero, neg_zero]
· exact if_neg hr.not_le
#align int.log_of_right_le_one Int.log_of_right_le_one
@[simp, norm_cast]
theorem log_natCast (b : ℕ) (n : ℕ) : log b (n : R) = Nat.log b n := by
cases n
· simp [log_of_right_le_one]
· rw [log_of_one_le_right, Nat.floor_natCast]
simp
#align int.log_nat_cast Int.log_natCast
-- See note [no_index around OfNat.ofNat]
@[simp]
theorem log_ofNat (b : ℕ) (n : ℕ) [n.AtLeastTwo] :
log b (no_index (OfNat.ofNat n : R)) = Nat.log b (OfNat.ofNat n) :=
log_natCast b n
theorem log_of_left_le_one {b : ℕ} (hb : b ≤ 1) (r : R) : log b r = 0 := by
rcases le_total 1 r with h | h
· rw [log_of_one_le_right _ h, Nat.log_of_left_le_one hb, Int.ofNat_zero]
· rw [log_of_right_le_one _ h, Nat.clog_of_left_le_one hb, Int.ofNat_zero, neg_zero]
#align int.log_of_left_le_one Int.log_of_left_le_one
theorem log_of_right_le_zero (b : ℕ) {r : R} (hr : r ≤ 0) : log b r = 0 := by
rw [log_of_right_le_one _ (hr.trans zero_le_one),
Nat.clog_of_right_le_one ((Nat.ceil_eq_zero.mpr <| inv_nonpos.2 hr).trans_le zero_le_one),
Int.ofNat_zero, neg_zero]
#align int.log_of_right_le_zero Int.log_of_right_le_zero
theorem zpow_log_le_self {b : ℕ} {r : R} (hb : 1 < b) (hr : 0 < r) : (b : R) ^ log b r ≤ r := by
rcases le_total 1 r with hr1 | hr1
· rw [log_of_one_le_right _ hr1]
rw [zpow_natCast, ← Nat.cast_pow, ← Nat.le_floor_iff hr.le]
exact Nat.pow_log_le_self b (Nat.floor_pos.mpr hr1).ne'
· rw [log_of_right_le_one _ hr1, zpow_neg, zpow_natCast, ← Nat.cast_pow]
exact inv_le_of_inv_le hr (Nat.ceil_le.1 <| Nat.le_pow_clog hb _)
#align int.zpow_log_le_self Int.zpow_log_le_self
theorem lt_zpow_succ_log_self {b : ℕ} (hb : 1 < b) (r : R) : r < (b : R) ^ (log b r + 1) := by
rcases le_or_lt r 0 with hr | hr
· rw [log_of_right_le_zero _ hr, zero_add, zpow_one]
exact hr.trans_lt (zero_lt_one.trans_le <| mod_cast hb.le)
rcases le_or_lt 1 r with hr1 | hr1
· rw [log_of_one_le_right _ hr1]
rw [Int.ofNat_add_one_out, zpow_natCast, ← Nat.cast_pow]
apply Nat.lt_of_floor_lt
exact Nat.lt_pow_succ_log_self hb _
· rw [log_of_right_le_one _ hr1.le]
have hcri : 1 < r⁻¹ := one_lt_inv hr hr1
have : 1 ≤ Nat.clog b ⌈r⁻¹⌉₊ :=
Nat.succ_le_of_lt (Nat.clog_pos hb <| Nat.one_lt_cast.1 <| hcri.trans_le (Nat.le_ceil _))
rw [neg_add_eq_sub, ← neg_sub, ← Int.ofNat_one, ← Int.ofNat_sub this, zpow_neg, zpow_natCast,
lt_inv hr (pow_pos (Nat.cast_pos.mpr <| zero_lt_one.trans hb) _), ← Nat.cast_pow]
refine Nat.lt_ceil.1 ?_
exact Nat.pow_pred_clog_lt_self hb <| Nat.one_lt_cast.1 <| hcri.trans_le <| Nat.le_ceil _
#align int.lt_zpow_succ_log_self Int.lt_zpow_succ_log_self
@[simp]
theorem log_zero_right (b : ℕ) : log b (0 : R) = 0 :=
log_of_right_le_zero b le_rfl
#align int.log_zero_right Int.log_zero_right
@[simp]
| Mathlib/Data/Int/Log.lean | 133 | 134 | theorem log_one_right (b : ℕ) : log b (1 : R) = 0 := by |
rw [log_of_one_le_right _ le_rfl, Nat.floor_one, Nat.log_one_right, Int.ofNat_zero]
| 0 |
import Mathlib.MeasureTheory.SetSemiring
open MeasurableSpace Set
namespace MeasureTheory
variable {α : Type*} {𝒜 : Set (Set α)} {s t : Set α}
structure IsSetAlgebra (𝒜 : Set (Set α)) : Prop where
empty_mem : ∅ ∈ 𝒜
compl_mem : ∀ ⦃s⦄, s ∈ 𝒜 → sᶜ ∈ 𝒜
union_mem : ∀ ⦃s t⦄, s ∈ 𝒜 → t ∈ 𝒜 → s ∪ t ∈ 𝒜
namespace IsSetAlgebra
theorem univ_mem (h𝒜 : IsSetAlgebra 𝒜) : univ ∈ 𝒜 :=
compl_empty ▸ h𝒜.compl_mem h𝒜.empty_mem
theorem inter_mem (h𝒜 : IsSetAlgebra 𝒜) (s_mem : s ∈ 𝒜) (t_mem : t ∈ 𝒜) :
s ∩ t ∈ 𝒜 :=
inter_eq_compl_compl_union_compl .. ▸
h𝒜.compl_mem (h𝒜.union_mem (h𝒜.compl_mem s_mem) (h𝒜.compl_mem t_mem))
theorem diff_mem (h𝒜 : IsSetAlgebra 𝒜) (s_mem : s ∈ 𝒜) (t_mem : t ∈ 𝒜) :
s \ t ∈ 𝒜 := h𝒜.inter_mem s_mem (h𝒜.compl_mem t_mem)
theorem isSetRing (h𝒜 : IsSetAlgebra 𝒜) : IsSetRing 𝒜 where
empty_mem := h𝒜.empty_mem
union_mem := h𝒜.union_mem
diff_mem := fun _ _ ↦ h𝒜.diff_mem
theorem biUnion_mem {ι : Type*} (h𝒜 : IsSetAlgebra 𝒜) {s : ι → Set α} (S : Finset ι)
(hs : ∀ i ∈ S, s i ∈ 𝒜) : ⋃ i ∈ S, s i ∈ 𝒜 := h𝒜.isSetRing.biUnion_mem S hs
| Mathlib/MeasureTheory/SetAlgebra.lean | 86 | 92 | theorem biInter_mem {ι : Type*} (h𝒜 : IsSetAlgebra 𝒜) {s : ι → Set α} (S : Finset ι)
(hs : ∀ i ∈ S, s i ∈ 𝒜) : ⋂ i ∈ S, s i ∈ 𝒜 := by |
by_cases h : S = ∅
· rw [h, ← Finset.set_biInter_coe, Finset.coe_empty, biInter_empty]
exact h𝒜.univ_mem
· rw [← ne_eq, ← Finset.nonempty_iff_ne_empty] at h
exact h𝒜.isSetRing.biInter_mem S h hs
| 0 |
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