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import Mathlib.MeasureTheory.Integral.IntegralEqImproper
#align_import measure_theory.integral.peak_function from "leanprover-community/mathlib"@"13b0d72fd8533ba459ac66e9a885e35ffabb32b2"
open Set Filter MeasureTheory MeasureTheory.Measure TopologicalSpace Metric
open scoped Topology ENNReal
open Set
variable {α E ι : Type*} {hm : MeasurableSpace α} {μ : Measure α} [TopologicalSpace α]
[BorelSpace α] [NormedAddCommGroup E] [NormedSpace ℝ E] {g : α → E} {l : Filter ι} {x₀ : α}
{s t : Set α} {φ : ι → α → ℝ} {a : E}
theorem integrableOn_peak_smul_of_integrableOn_of_tendsto
(hs : MeasurableSet s) (h'st : t ∈ 𝓝[s] x₀)
(hlφ : ∀ u : Set α, IsOpen u → x₀ ∈ u → TendstoUniformlyOn φ 0 l (s \ u))
(hiφ : Tendsto (fun i ↦ ∫ x in t, φ i x ∂μ) l (𝓝 1))
(h'iφ : ∀ᶠ i in l, AEStronglyMeasurable (φ i) (μ.restrict s))
(hmg : IntegrableOn g s μ) (hcg : Tendsto g (𝓝[s] x₀) (𝓝 a)) :
∀ᶠ i in l, IntegrableOn (fun x => φ i x • g x) s μ := by
obtain ⟨u, u_open, x₀u, ut, hu⟩ :
∃ u, IsOpen u ∧ x₀ ∈ u ∧ s ∩ u ⊆ t ∧ ∀ x ∈ u ∩ s, g x ∈ ball a 1 := by
rcases mem_nhdsWithin.1 (Filter.inter_mem h'st (hcg (ball_mem_nhds _ zero_lt_one)))
with ⟨u, u_open, x₀u, hu⟩
refine ⟨u, u_open, x₀u, ?_, hu.trans inter_subset_right⟩
rw [inter_comm]
exact hu.trans inter_subset_left
rw [tendsto_iff_norm_sub_tendsto_zero] at hiφ
filter_upwards [tendstoUniformlyOn_iff.1 (hlφ u u_open x₀u) 1 zero_lt_one,
(tendsto_order.1 hiφ).2 1 zero_lt_one, h'iφ] with i hi h'i h''i
have I : IntegrableOn (φ i) t μ := .of_integral_ne_zero (fun h ↦ by simp [h] at h'i)
have A : IntegrableOn (fun x => φ i x • g x) (s \ u) μ := by
refine Integrable.smul_of_top_right (hmg.mono diff_subset le_rfl) ?_
apply memℒp_top_of_bound (h''i.mono_set diff_subset) 1
filter_upwards [self_mem_ae_restrict (hs.diff u_open.measurableSet)] with x hx
simpa only [Pi.zero_apply, dist_zero_left] using (hi x hx).le
have B : IntegrableOn (fun x => φ i x • g x) (s ∩ u) μ := by
apply Integrable.smul_of_top_left
· exact IntegrableOn.mono_set I ut
· apply
memℒp_top_of_bound (hmg.mono_set inter_subset_left).aestronglyMeasurable (‖a‖ + 1)
filter_upwards [self_mem_ae_restrict (hs.inter u_open.measurableSet)] with x hx
rw [inter_comm] at hx
exact (norm_lt_of_mem_ball (hu x hx)).le
convert A.union B
simp only [diff_union_inter]
#align integrable_on_peak_smul_of_integrable_on_of_continuous_within_at integrableOn_peak_smul_of_integrableOn_of_tendsto
@[deprecated (since := "2024-02-20")]
alias integrableOn_peak_smul_of_integrableOn_of_continuousWithinAt :=
integrableOn_peak_smul_of_integrableOn_of_tendsto
variable [CompleteSpace E]
theorem tendsto_setIntegral_peak_smul_of_integrableOn_of_tendsto_aux
(hs : MeasurableSet s) (ht : MeasurableSet t) (hts : t ⊆ s) (h'ts : t ∈ 𝓝[s] x₀)
(hnφ : ∀ᶠ i in l, ∀ x ∈ s, 0 ≤ φ i x)
(hlφ : ∀ u : Set α, IsOpen u → x₀ ∈ u → TendstoUniformlyOn φ 0 l (s \ u))
(hiφ : Tendsto (fun i ↦ ∫ x in t, φ i x ∂μ) l (𝓝 1))
(h'iφ : ∀ᶠ i in l, AEStronglyMeasurable (φ i) (μ.restrict s))
(hmg : IntegrableOn g s μ) (hcg : Tendsto g (𝓝[s] x₀) (𝓝 0)) :
Tendsto (fun i : ι => ∫ x in s, φ i x • g x ∂μ) l (𝓝 0) := by
refine Metric.tendsto_nhds.2 fun ε εpos => ?_
obtain ⟨δ, hδ, δpos, δone⟩ : ∃ δ, (δ * ∫ x in s, ‖g x‖ ∂μ) + 2 * δ < ε ∧ 0 < δ ∧ δ < 1:= by
have A :
Tendsto (fun δ => (δ * ∫ x in s, ‖g x‖ ∂μ) + 2 * δ) (𝓝[>] 0)
(𝓝 ((0 * ∫ x in s, ‖g x‖ ∂μ) + 2 * 0)) := by
apply Tendsto.mono_left _ nhdsWithin_le_nhds
exact (tendsto_id.mul tendsto_const_nhds).add (tendsto_id.const_mul _)
rw [zero_mul, zero_add, mul_zero] at A
have : Ioo (0 : ℝ) 1 ∈ 𝓝[>] 0 := Ioo_mem_nhdsWithin_Ioi ⟨le_rfl, zero_lt_one⟩
rcases (((tendsto_order.1 A).2 ε εpos).and this).exists with ⟨δ, hδ, h'δ⟩
exact ⟨δ, hδ, h'δ.1, h'δ.2⟩
suffices ∀ᶠ i in l, ‖∫ x in s, φ i x • g x ∂μ‖ ≤ (δ * ∫ x in s, ‖g x‖ ∂μ) + 2 * δ by
filter_upwards [this] with i hi
simp only [dist_zero_right]
exact hi.trans_lt hδ
obtain ⟨u, u_open, x₀u, ut, hu⟩ :
∃ u, IsOpen u ∧ x₀ ∈ u ∧ s ∩ u ⊆ t ∧ ∀ x ∈ u ∩ s, g x ∈ ball 0 δ := by
rcases mem_nhdsWithin.1 (Filter.inter_mem h'ts (hcg (ball_mem_nhds _ δpos)))
with ⟨u, u_open, x₀u, hu⟩
refine ⟨u, u_open, x₀u, ?_, hu.trans inter_subset_right⟩
rw [inter_comm]
exact hu.trans inter_subset_left
filter_upwards [tendstoUniformlyOn_iff.1 (hlφ u u_open x₀u) δ δpos,
(tendsto_order.1 (tendsto_iff_norm_sub_tendsto_zero.1 hiφ)).2 δ δpos, hnφ,
integrableOn_peak_smul_of_integrableOn_of_tendsto hs h'ts hlφ hiφ h'iφ hmg hcg]
with i hi h'i hφpos h''i
have I : IntegrableOn (φ i) t μ := by
apply Integrable.of_integral_ne_zero (fun h ↦ ?_)
simp [h] at h'i
linarith
have B : ‖∫ x in s ∩ u, φ i x • g x ∂μ‖ ≤ 2 * δ :=
calc
‖∫ x in s ∩ u, φ i x • g x ∂μ‖ ≤ ∫ x in s ∩ u, ‖φ i x • g x‖ ∂μ :=
norm_integral_le_integral_norm _
_ ≤ ∫ x in s ∩ u, ‖φ i x‖ * δ ∂μ := by
refine setIntegral_mono_on ?_ ?_ (hs.inter u_open.measurableSet) fun x hx => ?_
· exact IntegrableOn.mono_set h''i.norm inter_subset_left
· exact IntegrableOn.mono_set (I.norm.mul_const _) ut
rw [norm_smul]
apply mul_le_mul_of_nonneg_left _ (norm_nonneg _)
rw [inter_comm] at hu
exact (mem_ball_zero_iff.1 (hu x hx)).le
_ ≤ ∫ x in t, ‖φ i x‖ * δ ∂μ := by
apply setIntegral_mono_set
· exact I.norm.mul_const _
· exact eventually_of_forall fun x => mul_nonneg (norm_nonneg _) δpos.le
· exact eventually_of_forall ut
_ = ∫ x in t, φ i x * δ ∂μ := by
apply setIntegral_congr ht fun x hx => ?_
rw [Real.norm_of_nonneg (hφpos _ (hts hx))]
_ = (∫ x in t, φ i x ∂μ) * δ := by rw [integral_mul_right]
_ ≤ 2 * δ := by gcongr; linarith [(le_abs_self _).trans h'i.le]
have C : ‖∫ x in s \ u, φ i x • g x ∂μ‖ ≤ δ * ∫ x in s, ‖g x‖ ∂μ :=
calc
‖∫ x in s \ u, φ i x • g x ∂μ‖ ≤ ∫ x in s \ u, ‖φ i x • g x‖ ∂μ :=
norm_integral_le_integral_norm _
_ ≤ ∫ x in s \ u, δ * ‖g x‖ ∂μ := by
refine setIntegral_mono_on ?_ ?_ (hs.diff u_open.measurableSet) fun x hx => ?_
· exact IntegrableOn.mono_set h''i.norm diff_subset
· exact IntegrableOn.mono_set (hmg.norm.const_mul _) diff_subset
rw [norm_smul]
apply mul_le_mul_of_nonneg_right _ (norm_nonneg _)
simpa only [Pi.zero_apply, dist_zero_left] using (hi x hx).le
_ ≤ δ * ∫ x in s, ‖g x‖ ∂μ := by
rw [integral_mul_left]
apply mul_le_mul_of_nonneg_left (setIntegral_mono_set hmg.norm _ _) δpos.le
· filter_upwards with x using norm_nonneg _
· filter_upwards using diff_subset (s := s) (t := u)
calc
‖∫ x in s, φ i x • g x ∂μ‖ =
‖(∫ x in s \ u, φ i x • g x ∂μ) + ∫ x in s ∩ u, φ i x • g x ∂μ‖ := by
conv_lhs => rw [← diff_union_inter s u]
rw [integral_union disjoint_sdiff_inter (hs.inter u_open.measurableSet)
(h''i.mono_set diff_subset) (h''i.mono_set inter_subset_left)]
_ ≤ ‖∫ x in s \ u, φ i x • g x ∂μ‖ + ‖∫ x in s ∩ u, φ i x • g x ∂μ‖ := norm_add_le _ _
_ ≤ (δ * ∫ x in s, ‖g x‖ ∂μ) + 2 * δ := add_le_add C B
#align tendsto_set_integral_peak_smul_of_integrable_on_of_continuous_within_at_aux tendsto_setIntegral_peak_smul_of_integrableOn_of_tendsto_aux
@[deprecated (since := "2024-02-20")]
alias tendsto_setIntegral_peak_smul_of_integrableOn_of_continuousWithinAt_aux :=
tendsto_setIntegral_peak_smul_of_integrableOn_of_tendsto_aux
theorem tendsto_setIntegral_peak_smul_of_integrableOn_of_tendsto
(hs : MeasurableSet s) {t : Set α} (ht : MeasurableSet t) (hts : t ⊆ s) (h'ts : t ∈ 𝓝[s] x₀)
(h't : μ t ≠ ∞) (hnφ : ∀ᶠ i in l, ∀ x ∈ s, 0 ≤ φ i x)
(hlφ : ∀ u : Set α, IsOpen u → x₀ ∈ u → TendstoUniformlyOn φ 0 l (s \ u))
(hiφ : Tendsto (fun i ↦ ∫ x in t, φ i x ∂μ) l (𝓝 1))
(h'iφ : ∀ᶠ i in l, AEStronglyMeasurable (φ i) (μ.restrict s))
(hmg : IntegrableOn g s μ) (hcg : Tendsto g (𝓝[s] x₀) (𝓝 a)) :
Tendsto (fun i : ι ↦ ∫ x in s, φ i x • g x ∂μ) l (𝓝 a) := by
let h := g - t.indicator (fun _ ↦ a)
have A : Tendsto (fun i : ι => (∫ x in s, φ i x • h x ∂μ) + (∫ x in t, φ i x ∂μ) • a) l
(𝓝 (0 + (1 : ℝ) • a)) := by
refine Tendsto.add ?_ (Tendsto.smul hiφ tendsto_const_nhds)
apply tendsto_setIntegral_peak_smul_of_integrableOn_of_tendsto_aux hs ht hts h'ts
hnφ hlφ hiφ h'iφ
· apply hmg.sub
simp only [integrable_indicator_iff ht, integrableOn_const, ht, Measure.restrict_apply]
right
exact lt_of_le_of_lt (measure_mono inter_subset_left) (h't.lt_top)
· rw [← sub_self a]
apply Tendsto.sub hcg
apply tendsto_const_nhds.congr'
filter_upwards [h'ts] with x hx using by simp [hx]
simp only [one_smul, zero_add] at A
refine Tendsto.congr' ?_ A
filter_upwards [integrableOn_peak_smul_of_integrableOn_of_tendsto hs h'ts
hlφ hiφ h'iφ hmg hcg,
(tendsto_order.1 (tendsto_iff_norm_sub_tendsto_zero.1 hiφ)).2 1 zero_lt_one] with i hi h'i
simp only [h, Pi.sub_apply, smul_sub, ← indicator_smul_apply]
rw [integral_sub hi, setIntegral_indicator ht, inter_eq_right.mpr hts,
integral_smul_const, sub_add_cancel]
rw [integrable_indicator_iff ht]
apply Integrable.smul_const
rw [restrict_restrict ht, inter_eq_left.mpr hts]
exact .of_integral_ne_zero (fun h ↦ by simp [h] at h'i)
#align tendsto_set_integral_peak_smul_of_integrable_on_of_continuous_within_at tendsto_setIntegral_peak_smul_of_integrableOn_of_tendsto
@[deprecated (since := "2024-02-20")]
alias tendsto_setIntegral_peak_smul_of_integrableOn_of_continuousWithinAt :=
tendsto_setIntegral_peak_smul_of_integrableOn_of_tendsto
theorem tendsto_integral_peak_smul_of_integrable_of_tendsto
{t : Set α} (ht : MeasurableSet t) (h'ts : t ∈ 𝓝 x₀)
(h't : μ t ≠ ∞) (hnφ : ∀ᶠ i in l, ∀ x, 0 ≤ φ i x)
(hlφ : ∀ u : Set α, IsOpen u → x₀ ∈ u → TendstoUniformlyOn φ 0 l uᶜ)
(hiφ : Tendsto (fun i ↦ ∫ x in t, φ i x ∂μ) l (𝓝 1))
(h'iφ : ∀ᶠ i in l, AEStronglyMeasurable (φ i) μ)
(hmg : Integrable g μ) (hcg : Tendsto g (𝓝 x₀) (𝓝 a)) :
Tendsto (fun i : ι ↦ ∫ x, φ i x • g x ∂μ) l (𝓝 a) := by
suffices Tendsto (fun i : ι ↦ ∫ x in univ, φ i x • g x ∂μ) l (𝓝 a) by simpa
exact tendsto_setIntegral_peak_smul_of_integrableOn_of_tendsto MeasurableSet.univ ht (x₀ := x₀)
(subset_univ _) (by simpa [nhdsWithin_univ]) h't (by simpa)
(by simpa [← compl_eq_univ_diff] using hlφ) hiφ
(by simpa) (by simpa) (by simpa [nhdsWithin_univ])
theorem tendsto_setIntegral_pow_smul_of_unique_maximum_of_isCompact_of_measure_nhdsWithin_pos
[MetrizableSpace α] [IsLocallyFiniteMeasure μ] (hs : IsCompact s)
(hμ : ∀ u, IsOpen u → x₀ ∈ u → 0 < μ (u ∩ s)) {c : α → ℝ} (hc : ContinuousOn c s)
(h'c : ∀ y ∈ s, y ≠ x₀ → c y < c x₀) (hnc : ∀ x ∈ s, 0 ≤ c x) (hnc₀ : 0 < c x₀) (h₀ : x₀ ∈ s)
(hmg : IntegrableOn g s μ) (hcg : ContinuousWithinAt g s x₀) :
Tendsto (fun n : ℕ => (∫ x in s, c x ^ n ∂μ)⁻¹ • ∫ x in s, c x ^ n • g x ∂μ)
atTop (𝓝 (g x₀)) := by
let φ : ℕ → α → ℝ := fun n x => (∫ x in s, c x ^ n ∂μ)⁻¹ * c x ^ n
have hnφ : ∀ n, ∀ x ∈ s, 0 ≤ φ n x := by
intro n x hx
apply mul_nonneg (inv_nonneg.2 _) (pow_nonneg (hnc x hx) _)
exact setIntegral_nonneg hs.measurableSet fun x hx => pow_nonneg (hnc x hx) _
have I : ∀ n, IntegrableOn (fun x => c x ^ n) s μ := fun n =>
ContinuousOn.integrableOn_compact hs (hc.pow n)
have J : ∀ n, 0 ≤ᵐ[μ.restrict s] fun x : α => c x ^ n := by
intro n
filter_upwards [ae_restrict_mem hs.measurableSet] with x hx
exact pow_nonneg (hnc x hx) n
have P : ∀ n, (0 : ℝ) < ∫ x in s, c x ^ n ∂μ := by
intro n
refine (setIntegral_pos_iff_support_of_nonneg_ae (J n) (I n)).2 ?_
obtain ⟨u, u_open, x₀_u, hu⟩ : ∃ u : Set α, IsOpen u ∧ x₀ ∈ u ∧ u ∩ s ⊆ c ⁻¹' Ioi 0 :=
_root_.continuousOn_iff.1 hc x₀ h₀ (Ioi (0 : ℝ)) isOpen_Ioi hnc₀
apply (hμ u u_open x₀_u).trans_le
exact measure_mono fun x hx => ⟨ne_of_gt (pow_pos (a := c x) (hu hx) _), hx.2⟩
have hiφ : ∀ n, ∫ x in s, φ n x ∂μ = 1 := fun n => by
rw [integral_mul_left, inv_mul_cancel (P n).ne']
have A : ∀ u : Set α, IsOpen u → x₀ ∈ u → TendstoUniformlyOn φ 0 atTop (s \ u) := by
intro u u_open x₀u
obtain ⟨t, t_pos, tx₀, ht⟩ : ∃ t, 0 ≤ t ∧ t < c x₀ ∧ ∀ x ∈ s \ u, c x ≤ t := by
rcases eq_empty_or_nonempty (s \ u) with (h | h)
· exact
⟨0, le_rfl, hnc₀, by simp only [h, mem_empty_iff_false, IsEmpty.forall_iff, imp_true_iff]⟩
obtain ⟨x, hx, h'x⟩ : ∃ x ∈ s \ u, ∀ y ∈ s \ u, c y ≤ c x :=
IsCompact.exists_isMaxOn (hs.diff u_open) h (hc.mono diff_subset)
refine ⟨c x, hnc x hx.1, h'c x hx.1 ?_, h'x⟩
rintro rfl
exact hx.2 x₀u
obtain ⟨t', tt', t'x₀⟩ : ∃ t', t < t' ∧ t' < c x₀ := exists_between tx₀
have t'_pos : 0 < t' := t_pos.trans_lt tt'
obtain ⟨v, v_open, x₀_v, hv⟩ : ∃ v : Set α, IsOpen v ∧ x₀ ∈ v ∧ v ∩ s ⊆ c ⁻¹' Ioi t' :=
_root_.continuousOn_iff.1 hc x₀ h₀ (Ioi t') isOpen_Ioi t'x₀
have M : ∀ n, ∀ x ∈ s \ u, φ n x ≤ (μ (v ∩ s)).toReal⁻¹ * (t / t') ^ n := by
intro n x hx
have B : t' ^ n * (μ (v ∩ s)).toReal ≤ ∫ y in s, c y ^ n ∂μ :=
calc
t' ^ n * (μ (v ∩ s)).toReal = ∫ _ in v ∩ s, t' ^ n ∂μ := by
simp only [integral_const, Measure.restrict_apply, MeasurableSet.univ, univ_inter,
Algebra.id.smul_eq_mul, mul_comm]
_ ≤ ∫ y in v ∩ s, c y ^ n ∂μ := by
apply setIntegral_mono_on _ _ (v_open.measurableSet.inter hs.measurableSet) _
· apply integrableOn_const.2 (Or.inr _)
exact lt_of_le_of_lt (measure_mono inter_subset_right) hs.measure_lt_top
· exact (I n).mono inter_subset_right le_rfl
· intro x hx
exact pow_le_pow_left t'_pos.le (le_of_lt (hv hx)) _
_ ≤ ∫ y in s, c y ^ n ∂μ :=
setIntegral_mono_set (I n) (J n) (eventually_of_forall inter_subset_right)
simp_rw [φ, ← div_eq_inv_mul, div_pow, div_div]
apply div_le_div (pow_nonneg t_pos n) _ _ B
· exact pow_le_pow_left (hnc _ hx.1) (ht x hx) _
· apply mul_pos (pow_pos (t_pos.trans_lt tt') _) (ENNReal.toReal_pos (hμ v v_open x₀_v).ne' _)
have : μ (v ∩ s) ≤ μ s := measure_mono inter_subset_right
exact ne_of_lt (lt_of_le_of_lt this hs.measure_lt_top)
have N :
Tendsto (fun n => (μ (v ∩ s)).toReal⁻¹ * (t / t') ^ n) atTop
(𝓝 ((μ (v ∩ s)).toReal⁻¹ * 0)) := by
apply Tendsto.mul tendsto_const_nhds _
apply tendsto_pow_atTop_nhds_zero_of_lt_one (div_nonneg t_pos t'_pos.le)
exact (div_lt_one t'_pos).2 tt'
rw [mul_zero] at N
refine tendstoUniformlyOn_iff.2 fun ε εpos => ?_
filter_upwards [(tendsto_order.1 N).2 ε εpos] with n hn x hx
simp only [Pi.zero_apply, dist_zero_left, Real.norm_of_nonneg (hnφ n x hx.1)]
exact (M n x hx).trans_lt hn
have : Tendsto (fun i : ℕ => ∫ x : α in s, φ i x • g x ∂μ) atTop (𝓝 (g x₀)) := by
have B : Tendsto (fun i ↦ ∫ (x : α) in s, φ i x ∂μ) atTop (𝓝 1) :=
tendsto_const_nhds.congr (fun n ↦ (hiφ n).symm)
have C : ∀ᶠ (i : ℕ) in atTop, AEStronglyMeasurable (fun x ↦ φ i x) (μ.restrict s) := by
apply eventually_of_forall (fun n ↦ ((I n).const_mul _).aestronglyMeasurable)
exact tendsto_setIntegral_peak_smul_of_integrableOn_of_tendsto hs.measurableSet
hs.measurableSet (Subset.rfl) (self_mem_nhdsWithin)
hs.measure_lt_top.ne (eventually_of_forall hnφ) A B C hmg hcg
convert this
simp_rw [φ, ← smul_smul, integral_smul]
#align tendsto_set_integral_pow_smul_of_unique_maximum_of_is_compact_of_measure_nhds_within_pos tendsto_setIntegral_pow_smul_of_unique_maximum_of_isCompact_of_measure_nhdsWithin_pos
theorem tendsto_setIntegral_pow_smul_of_unique_maximum_of_isCompact_of_integrableOn
[MetrizableSpace α] [IsLocallyFiniteMeasure μ] [IsOpenPosMeasure μ] (hs : IsCompact s)
{c : α → ℝ} (hc : ContinuousOn c s) (h'c : ∀ y ∈ s, y ≠ x₀ → c y < c x₀)
(hnc : ∀ x ∈ s, 0 ≤ c x) (hnc₀ : 0 < c x₀) (h₀ : x₀ ∈ closure (interior s))
(hmg : IntegrableOn g s μ) (hcg : ContinuousWithinAt g s x₀) :
Tendsto (fun n : ℕ => (∫ x in s, c x ^ n ∂μ)⁻¹ • ∫ x in s, c x ^ n • g x ∂μ) atTop
(𝓝 (g x₀)) := by
have : x₀ ∈ s := by rw [← hs.isClosed.closure_eq]; exact closure_mono interior_subset h₀
apply
tendsto_setIntegral_pow_smul_of_unique_maximum_of_isCompact_of_measure_nhdsWithin_pos hs _ hc
h'c hnc hnc₀ this hmg hcg
intro u u_open x₀_u
calc
0 < μ (u ∩ interior s) :=
(u_open.inter isOpen_interior).measure_pos μ (_root_.mem_closure_iff.1 h₀ u u_open x₀_u)
_ ≤ μ (u ∩ s) := by gcongr; apply interior_subset
#align tendsto_set_integral_pow_smul_of_unique_maximum_of_is_compact_of_integrable_on tendsto_setIntegral_pow_smul_of_unique_maximum_of_isCompact_of_integrableOn
theorem tendsto_setIntegral_pow_smul_of_unique_maximum_of_isCompact_of_continuousOn
[MetrizableSpace α] [IsLocallyFiniteMeasure μ] [IsOpenPosMeasure μ] (hs : IsCompact s)
{c : α → ℝ} (hc : ContinuousOn c s) (h'c : ∀ y ∈ s, y ≠ x₀ → c y < c x₀)
(hnc : ∀ x ∈ s, 0 ≤ c x) (hnc₀ : 0 < c x₀) (h₀ : x₀ ∈ closure (interior s))
(hmg : ContinuousOn g s) :
Tendsto (fun n : ℕ => (∫ x in s, c x ^ n ∂μ)⁻¹ • ∫ x in s, c x ^ n • g x ∂μ) atTop (𝓝 (g x₀)) :=
haveI : x₀ ∈ s := by rw [← hs.isClosed.closure_eq]; exact closure_mono interior_subset h₀
tendsto_setIntegral_pow_smul_of_unique_maximum_of_isCompact_of_integrableOn hs hc h'c hnc hnc₀ h₀
(hmg.integrableOn_compact hs) (hmg x₀ this)
#align tendsto_set_integral_pow_smul_of_unique_maximum_of_is_compact_of_continuous_on tendsto_setIntegral_pow_smul_of_unique_maximum_of_isCompact_of_continuousOn
open FiniteDimensional Bornology
variable {F : Type*} [NormedAddCommGroup F] [NormedSpace ℝ F] [FiniteDimensional ℝ F]
[MeasurableSpace F] [BorelSpace F] {μ : Measure F} [IsAddHaarMeasure μ]
| Mathlib/MeasureTheory/Integral/PeakFunction.lean | 412 | 464 | theorem tendsto_integral_comp_smul_smul_of_integrable
{φ : F → ℝ} (hφ : ∀ x, 0 ≤ φ x) (h'φ : ∫ x, φ x ∂μ = 1)
(h : Tendsto (fun x ↦ ‖x‖ ^ finrank ℝ F * φ x) (cobounded F) (𝓝 0))
{g : F → E} (hg : Integrable g μ) (h'g : ContinuousAt g 0) :
Tendsto (fun (c : ℝ) ↦ ∫ x, (c ^ (finrank ℝ F) * φ (c • x)) • g x ∂μ) atTop (𝓝 (g 0)) := by |
have I : Integrable φ μ := integrable_of_integral_eq_one h'φ
apply tendsto_integral_peak_smul_of_integrable_of_tendsto (t := closedBall 0 1) (x₀ := 0)
· exact isClosed_ball.measurableSet
· exact closedBall_mem_nhds _ zero_lt_one
· exact (isCompact_closedBall 0 1).measure_ne_top
· filter_upwards [Ici_mem_atTop 0] with c (hc : 0 ≤ c) x using mul_nonneg (by positivity) (hφ _)
· intro u u_open hu
apply tendstoUniformlyOn_iff.2 (fun ε εpos ↦ ?_)
obtain ⟨δ, δpos, h'u⟩ : ∃ δ > 0, ball 0 δ ⊆ u := Metric.isOpen_iff.1 u_open _ hu
obtain ⟨M, Mpos, hM⟩ : ∃ M > 0, ∀ ⦃x : F⦄, x ∈ (closedBall 0 M)ᶜ →
‖x‖ ^ finrank ℝ F * φ x < δ ^ finrank ℝ F * ε := by
rcases (hasBasis_cobounded_compl_closedBall (0 : F)).eventually_iff.1
((tendsto_order.1 h).2 (δ ^ finrank ℝ F * ε) (by positivity)) with ⟨M, -, hM⟩
refine ⟨max M 1, zero_lt_one.trans_le (le_max_right _ _), fun x hx ↦ hM ?_⟩
simp only [mem_compl_iff, mem_closedBall, dist_zero_right, le_max_iff, not_or, not_le] at hx
simpa using hx.1
filter_upwards [Ioi_mem_atTop (M / δ)] with c (hc : M / δ < c) x hx
have cpos : 0 < c := lt_trans (by positivity) hc
suffices c ^ finrank ℝ F * φ (c • x) < ε by simpa [abs_of_nonneg (hφ _), abs_of_nonneg cpos.le]
have hδx : δ ≤ ‖x‖ := by
have : x ∈ (ball 0 δ)ᶜ := fun h ↦ hx (h'u h)
simpa only [mem_compl_iff, mem_ball, dist_zero_right, not_lt]
suffices δ ^ finrank ℝ F * (c ^ finrank ℝ F * φ (c • x)) < δ ^ finrank ℝ F * ε by
rwa [mul_lt_mul_iff_of_pos_left (by positivity)] at this
calc
δ ^ finrank ℝ F * (c ^ finrank ℝ F * φ (c • x))
_ ≤ ‖x‖ ^ finrank ℝ F * (c ^ finrank ℝ F * φ (c • x)) := by
gcongr; exact mul_nonneg (by positivity) (hφ _)
_ = ‖c • x‖ ^ finrank ℝ F * φ (c • x) := by
simp [norm_smul, abs_of_pos cpos, mul_pow]; ring
_ < δ ^ finrank ℝ F * ε := by
apply hM
rw [div_lt_iff δpos] at hc
simp only [mem_compl_iff, mem_closedBall, dist_zero_right, norm_smul, Real.norm_eq_abs,
abs_of_nonneg cpos.le, not_le, gt_iff_lt]
exact hc.trans_le (by gcongr)
· have : Tendsto (fun c ↦ ∫ (x : F) in closedBall 0 c, φ x ∂μ) atTop (𝓝 1) := by
rw [← h'φ]
exact (aecover_closedBall tendsto_id).integral_tendsto_of_countably_generated I
apply this.congr'
filter_upwards [Ioi_mem_atTop 0] with c (hc : 0 < c)
rw [integral_mul_left, setIntegral_comp_smul_of_pos _ _ _ hc, smul_eq_mul, ← mul_assoc,
mul_inv_cancel (by positivity), _root_.smul_closedBall _ _ zero_le_one]
simp [abs_of_nonneg hc.le]
· filter_upwards [Ioi_mem_atTop 0] with c (hc : 0 < c)
exact (I.comp_smul hc.ne').aestronglyMeasurable.const_mul _
· exact hg
· exact h'g
|
import Mathlib.Analysis.SpecialFunctions.Trigonometric.ArctanDeriv
#align_import analysis.special_functions.trigonometric.bounds from "leanprover-community/mathlib"@"2c1d8ca2812b64f88992a5294ea3dba144755cd1"
open Set
namespace Real
variable {x : ℝ}
| Mathlib/Analysis/SpecialFunctions/Trigonometric/Bounds.lean | 39 | 49 | theorem sin_lt (h : 0 < x) : sin x < x := by |
cases' lt_or_le 1 x with h' h'
· exact (sin_le_one x).trans_lt h'
have hx : |x| = x := abs_of_nonneg h.le
have := le_of_abs_le (sin_bound <| show |x| ≤ 1 by rwa [hx])
rw [sub_le_iff_le_add', hx] at this
apply this.trans_lt
rw [sub_add, sub_lt_self_iff, sub_pos, div_eq_mul_inv (x ^ 3)]
refine mul_lt_mul' ?_ (by norm_num) (by norm_num) (pow_pos h 3)
apply pow_le_pow_of_le_one h.le h'
norm_num
|
import Mathlib.Data.Set.Prod
#align_import data.set.n_ary from "leanprover-community/mathlib"@"5e526d18cea33550268dcbbddcb822d5cde40654"
open Function
namespace Set
variable {α α' β β' γ γ' δ δ' ε ε' ζ ζ' ν : Type*} {f f' : α → β → γ} {g g' : α → β → γ → δ}
variable {s s' : Set α} {t t' : Set β} {u u' : Set γ} {v : Set δ} {a a' : α} {b b' : β} {c c' : γ}
{d d' : δ}
theorem mem_image2_iff (hf : Injective2 f) : f a b ∈ image2 f s t ↔ a ∈ s ∧ b ∈ t :=
⟨by
rintro ⟨a', ha', b', hb', h⟩
rcases hf h with ⟨rfl, rfl⟩
exact ⟨ha', hb'⟩, fun ⟨ha, hb⟩ => mem_image2_of_mem ha hb⟩
#align set.mem_image2_iff Set.mem_image2_iff
theorem image2_subset (hs : s ⊆ s') (ht : t ⊆ t') : image2 f s t ⊆ image2 f s' t' := by
rintro _ ⟨a, ha, b, hb, rfl⟩
exact mem_image2_of_mem (hs ha) (ht hb)
#align set.image2_subset Set.image2_subset
theorem image2_subset_left (ht : t ⊆ t') : image2 f s t ⊆ image2 f s t' :=
image2_subset Subset.rfl ht
#align set.image2_subset_left Set.image2_subset_left
theorem image2_subset_right (hs : s ⊆ s') : image2 f s t ⊆ image2 f s' t :=
image2_subset hs Subset.rfl
#align set.image2_subset_right Set.image2_subset_right
theorem image_subset_image2_left (hb : b ∈ t) : (fun a => f a b) '' s ⊆ image2 f s t :=
forall_mem_image.2 fun _ ha => mem_image2_of_mem ha hb
#align set.image_subset_image2_left Set.image_subset_image2_left
theorem image_subset_image2_right (ha : a ∈ s) : f a '' t ⊆ image2 f s t :=
forall_mem_image.2 fun _ => mem_image2_of_mem ha
#align set.image_subset_image2_right Set.image_subset_image2_right
theorem forall_image2_iff {p : γ → Prop} :
(∀ z ∈ image2 f s t, p z) ↔ ∀ x ∈ s, ∀ y ∈ t, p (f x y) :=
⟨fun h x hx y hy => h _ ⟨x, hx, y, hy, rfl⟩, fun h _ ⟨x, hx, y, hy, hz⟩ => hz ▸ h x hx y hy⟩
#align set.forall_image2_iff Set.forall_image2_iff
@[simp]
theorem image2_subset_iff {u : Set γ} : image2 f s t ⊆ u ↔ ∀ x ∈ s, ∀ y ∈ t, f x y ∈ u :=
forall_image2_iff
#align set.image2_subset_iff Set.image2_subset_iff
theorem image2_subset_iff_left : image2 f s t ⊆ u ↔ ∀ a ∈ s, (fun b => f a b) '' t ⊆ u := by
simp_rw [image2_subset_iff, image_subset_iff, subset_def, mem_preimage]
#align set.image2_subset_iff_left Set.image2_subset_iff_left
theorem image2_subset_iff_right : image2 f s t ⊆ u ↔ ∀ b ∈ t, (fun a => f a b) '' s ⊆ u := by
simp_rw [image2_subset_iff, image_subset_iff, subset_def, mem_preimage, @forall₂_swap α]
#align set.image2_subset_iff_right Set.image2_subset_iff_right
variable (f)
-- Porting note: Removing `simp` - LHS does not simplify
lemma image_prod : (fun x : α × β ↦ f x.1 x.2) '' s ×ˢ t = image2 f s t :=
ext fun _ ↦ by simp [and_assoc]
#align set.image_prod Set.image_prod
@[simp] lemma image_uncurry_prod (s : Set α) (t : Set β) : uncurry f '' s ×ˢ t = image2 f s t :=
image_prod _
#align set.image_uncurry_prod Set.image_uncurry_prod
@[simp] lemma image2_mk_eq_prod : image2 Prod.mk s t = s ×ˢ t := ext <| by simp
#align set.image2_mk_eq_prod Set.image2_mk_eq_prod
-- Porting note: Removing `simp` - LHS does not simplify
lemma image2_curry (f : α × β → γ) (s : Set α) (t : Set β) :
image2 (fun a b ↦ f (a, b)) s t = f '' s ×ˢ t := by
simp [← image_uncurry_prod, uncurry]
#align set.image2_curry Set.image2_curry
theorem image2_swap (s : Set α) (t : Set β) : image2 f s t = image2 (fun a b => f b a) t s := by
ext
constructor <;> rintro ⟨a, ha, b, hb, rfl⟩ <;> exact ⟨b, hb, a, ha, rfl⟩
#align set.image2_swap Set.image2_swap
variable {f}
theorem image2_union_left : image2 f (s ∪ s') t = image2 f s t ∪ image2 f s' t := by
simp_rw [← image_prod, union_prod, image_union]
#align set.image2_union_left Set.image2_union_left
theorem image2_union_right : image2 f s (t ∪ t') = image2 f s t ∪ image2 f s t' := by
rw [← image2_swap, image2_union_left, image2_swap f, image2_swap f]
#align set.image2_union_right Set.image2_union_right
lemma image2_inter_left (hf : Injective2 f) :
image2 f (s ∩ s') t = image2 f s t ∩ image2 f s' t := by
simp_rw [← image_uncurry_prod, inter_prod, image_inter hf.uncurry]
#align set.image2_inter_left Set.image2_inter_left
lemma image2_inter_right (hf : Injective2 f) :
image2 f s (t ∩ t') = image2 f s t ∩ image2 f s t' := by
simp_rw [← image_uncurry_prod, prod_inter, image_inter hf.uncurry]
#align set.image2_inter_right Set.image2_inter_right
@[simp]
theorem image2_empty_left : image2 f ∅ t = ∅ :=
ext <| by simp
#align set.image2_empty_left Set.image2_empty_left
@[simp]
theorem image2_empty_right : image2 f s ∅ = ∅ :=
ext <| by simp
#align set.image2_empty_right Set.image2_empty_right
theorem Nonempty.image2 : s.Nonempty → t.Nonempty → (image2 f s t).Nonempty :=
fun ⟨_, ha⟩ ⟨_, hb⟩ => ⟨_, mem_image2_of_mem ha hb⟩
#align set.nonempty.image2 Set.Nonempty.image2
@[simp]
theorem image2_nonempty_iff : (image2 f s t).Nonempty ↔ s.Nonempty ∧ t.Nonempty :=
⟨fun ⟨_, a, ha, b, hb, _⟩ => ⟨⟨a, ha⟩, b, hb⟩, fun h => h.1.image2 h.2⟩
#align set.image2_nonempty_iff Set.image2_nonempty_iff
theorem Nonempty.of_image2_left (h : (Set.image2 f s t).Nonempty) : s.Nonempty :=
(image2_nonempty_iff.1 h).1
#align set.nonempty.of_image2_left Set.Nonempty.of_image2_left
theorem Nonempty.of_image2_right (h : (Set.image2 f s t).Nonempty) : t.Nonempty :=
(image2_nonempty_iff.1 h).2
#align set.nonempty.of_image2_right Set.Nonempty.of_image2_right
@[simp]
theorem image2_eq_empty_iff : image2 f s t = ∅ ↔ s = ∅ ∨ t = ∅ := by
rw [← not_nonempty_iff_eq_empty, image2_nonempty_iff, not_and_or]
simp [not_nonempty_iff_eq_empty]
#align set.image2_eq_empty_iff Set.image2_eq_empty_iff
theorem Subsingleton.image2 (hs : s.Subsingleton) (ht : t.Subsingleton) (f : α → β → γ) :
(image2 f s t).Subsingleton := by
rw [← image_prod]
apply (hs.prod ht).image
theorem image2_inter_subset_left : image2 f (s ∩ s') t ⊆ image2 f s t ∩ image2 f s' t :=
Monotone.map_inf_le (fun _ _ ↦ image2_subset_right) s s'
#align set.image2_inter_subset_left Set.image2_inter_subset_left
theorem image2_inter_subset_right : image2 f s (t ∩ t') ⊆ image2 f s t ∩ image2 f s t' :=
Monotone.map_inf_le (fun _ _ ↦ image2_subset_left) t t'
#align set.image2_inter_subset_right Set.image2_inter_subset_right
@[simp]
theorem image2_singleton_left : image2 f {a} t = f a '' t :=
ext fun x => by simp
#align set.image2_singleton_left Set.image2_singleton_left
@[simp]
theorem image2_singleton_right : image2 f s {b} = (fun a => f a b) '' s :=
ext fun x => by simp
#align set.image2_singleton_right Set.image2_singleton_right
theorem image2_singleton : image2 f {a} {b} = {f a b} := by simp
#align set.image2_singleton Set.image2_singleton
@[simp]
| Mathlib/Data/Set/NAry.lean | 181 | 182 | theorem image2_insert_left : image2 f (insert a s) t = (fun b => f a b) '' t ∪ image2 f s t := by |
rw [insert_eq, image2_union_left, image2_singleton_left]
|
import Mathlib.Algebra.Group.Commute.Basic
import Mathlib.Data.Fintype.Card
import Mathlib.GroupTheory.Perm.Basic
#align_import group_theory.perm.support from "leanprover-community/mathlib"@"9003f28797c0664a49e4179487267c494477d853"
open Equiv Finset
namespace Equiv.Perm
variable {α : Type*}
section Disjoint
def Disjoint (f g : Perm α) :=
∀ x, f x = x ∨ g x = x
#align equiv.perm.disjoint Equiv.Perm.Disjoint
variable {f g h : Perm α}
@[symm]
theorem Disjoint.symm : Disjoint f g → Disjoint g f := by simp only [Disjoint, or_comm, imp_self]
#align equiv.perm.disjoint.symm Equiv.Perm.Disjoint.symm
theorem Disjoint.symmetric : Symmetric (@Disjoint α) := fun _ _ => Disjoint.symm
#align equiv.perm.disjoint.symmetric Equiv.Perm.Disjoint.symmetric
instance : IsSymm (Perm α) Disjoint :=
⟨Disjoint.symmetric⟩
theorem disjoint_comm : Disjoint f g ↔ Disjoint g f :=
⟨Disjoint.symm, Disjoint.symm⟩
#align equiv.perm.disjoint_comm Equiv.Perm.disjoint_comm
theorem Disjoint.commute (h : Disjoint f g) : Commute f g :=
Equiv.ext fun x =>
(h x).elim
(fun hf =>
(h (g x)).elim (fun hg => by simp [mul_apply, hf, hg]) fun hg => by
simp [mul_apply, hf, g.injective hg])
fun hg =>
(h (f x)).elim (fun hf => by simp [mul_apply, f.injective hf, hg]) fun hf => by
simp [mul_apply, hf, hg]
#align equiv.perm.disjoint.commute Equiv.Perm.Disjoint.commute
@[simp]
theorem disjoint_one_left (f : Perm α) : Disjoint 1 f := fun _ => Or.inl rfl
#align equiv.perm.disjoint_one_left Equiv.Perm.disjoint_one_left
@[simp]
theorem disjoint_one_right (f : Perm α) : Disjoint f 1 := fun _ => Or.inr rfl
#align equiv.perm.disjoint_one_right Equiv.Perm.disjoint_one_right
theorem disjoint_iff_eq_or_eq : Disjoint f g ↔ ∀ x : α, f x = x ∨ g x = x :=
Iff.rfl
#align equiv.perm.disjoint_iff_eq_or_eq Equiv.Perm.disjoint_iff_eq_or_eq
@[simp]
| Mathlib/GroupTheory/Perm/Support.lean | 87 | 90 | theorem disjoint_refl_iff : Disjoint f f ↔ f = 1 := by |
refine ⟨fun h => ?_, fun h => h.symm ▸ disjoint_one_left 1⟩
ext x
cases' h x with hx hx <;> simp [hx]
|
import Mathlib.Order.Interval.Set.UnorderedInterval
import Mathlib.Algebra.Order.Interval.Set.Monoid
import Mathlib.Data.Set.Pointwise.Basic
import Mathlib.Algebra.Order.Field.Basic
import Mathlib.Algebra.Order.Group.MinMax
#align_import data.set.pointwise.interval from "leanprover-community/mathlib"@"2196ab363eb097c008d4497125e0dde23fb36db2"
open Interval Pointwise
variable {α : Type*}
namespace Set
section ContravariantLT
variable [Mul α] [PartialOrder α]
variable [CovariantClass α α (· * ·) (· < ·)] [CovariantClass α α (Function.swap HMul.hMul) LT.lt]
@[to_additive Icc_add_Ico_subset]
theorem Icc_mul_Ico_subset' (a b c d : α) : Icc a b * Ico c d ⊆ Ico (a * c) (b * d) := by
haveI := covariantClass_le_of_lt
rintro x ⟨y, ⟨hya, hyb⟩, z, ⟨hzc, hzd⟩, rfl⟩
exact ⟨mul_le_mul' hya hzc, mul_lt_mul_of_le_of_lt hyb hzd⟩
@[to_additive Ico_add_Icc_subset]
theorem Ico_mul_Icc_subset' (a b c d : α) : Ico a b * Icc c d ⊆ Ico (a * c) (b * d) := by
haveI := covariantClass_le_of_lt
rintro x ⟨y, ⟨hya, hyb⟩, z, ⟨hzc, hzd⟩, rfl⟩
exact ⟨mul_le_mul' hya hzc, mul_lt_mul_of_lt_of_le hyb hzd⟩
@[to_additive Ioc_add_Ico_subset]
theorem Ioc_mul_Ico_subset' (a b c d : α) : Ioc a b * Ico c d ⊆ Ioo (a * c) (b * d) := by
haveI := covariantClass_le_of_lt
rintro x ⟨y, ⟨hya, hyb⟩, z, ⟨hzc, hzd⟩, rfl⟩
exact ⟨mul_lt_mul_of_lt_of_le hya hzc, mul_lt_mul_of_le_of_lt hyb hzd⟩
@[to_additive Ico_add_Ioc_subset]
| Mathlib/Data/Set/Pointwise/Interval.lean | 86 | 89 | theorem Ico_mul_Ioc_subset' (a b c d : α) : Ico a b * Ioc c d ⊆ Ioo (a * c) (b * d) := by |
haveI := covariantClass_le_of_lt
rintro x ⟨y, ⟨hya, hyb⟩, z, ⟨hzc, hzd⟩, rfl⟩
exact ⟨mul_lt_mul_of_le_of_lt hya hzc, mul_lt_mul_of_lt_of_le hyb hzd⟩
|
import Mathlib.Data.Set.Function
import Mathlib.Order.Interval.Set.OrdConnected
#align_import data.set.intervals.proj_Icc from "leanprover-community/mathlib"@"4e24c4bfcff371c71f7ba22050308aa17815626c"
variable {α β : Type*} [LinearOrder α]
open Function
namespace Set
def projIci (a x : α) : Ici a := ⟨max a x, le_max_left _ _⟩
#align set.proj_Ici Set.projIci
def projIic (b x : α) : Iic b := ⟨min b x, min_le_left _ _⟩
#align set.proj_Iic Set.projIic
def projIcc (a b : α) (h : a ≤ b) (x : α) : Icc a b :=
⟨max a (min b x), le_max_left _ _, max_le h (min_le_left _ _)⟩
#align set.proj_Icc Set.projIcc
variable {a b : α} (h : a ≤ b) {x : α}
@[norm_cast]
theorem coe_projIci (a x : α) : (projIci a x : α) = max a x := rfl
#align set.coe_proj_Ici Set.coe_projIci
@[norm_cast]
theorem coe_projIic (b x : α) : (projIic b x : α) = min b x := rfl
#align set.coe_proj_Iic Set.coe_projIic
@[norm_cast]
theorem coe_projIcc (a b : α) (h : a ≤ b) (x : α) : (projIcc a b h x : α) = max a (min b x) := rfl
#align set.coe_proj_Icc Set.coe_projIcc
theorem projIci_of_le (hx : x ≤ a) : projIci a x = ⟨a, le_rfl⟩ := Subtype.ext <| max_eq_left hx
#align set.proj_Ici_of_le Set.projIci_of_le
theorem projIic_of_le (hx : b ≤ x) : projIic b x = ⟨b, le_rfl⟩ := Subtype.ext <| min_eq_left hx
#align set.proj_Iic_of_le Set.projIic_of_le
theorem projIcc_of_le_left (hx : x ≤ a) : projIcc a b h x = ⟨a, left_mem_Icc.2 h⟩ := by
simp [projIcc, hx, hx.trans h]
#align set.proj_Icc_of_le_left Set.projIcc_of_le_left
theorem projIcc_of_right_le (hx : b ≤ x) : projIcc a b h x = ⟨b, right_mem_Icc.2 h⟩ := by
simp [projIcc, hx, h]
#align set.proj_Icc_of_right_le Set.projIcc_of_right_le
@[simp]
theorem projIci_self (a : α) : projIci a a = ⟨a, le_rfl⟩ := projIci_of_le le_rfl
#align set.proj_Ici_self Set.projIci_self
@[simp]
theorem projIic_self (b : α) : projIic b b = ⟨b, le_rfl⟩ := projIic_of_le le_rfl
#align set.proj_Iic_self Set.projIic_self
@[simp]
theorem projIcc_left : projIcc a b h a = ⟨a, left_mem_Icc.2 h⟩ :=
projIcc_of_le_left h le_rfl
#align set.proj_Icc_left Set.projIcc_left
@[simp]
theorem projIcc_right : projIcc a b h b = ⟨b, right_mem_Icc.2 h⟩ :=
projIcc_of_right_le h le_rfl
#align set.proj_Icc_right Set.projIcc_right
theorem projIci_eq_self : projIci a x = ⟨a, le_rfl⟩ ↔ x ≤ a := by simp [projIci, Subtype.ext_iff]
#align set.proj_Ici_eq_self Set.projIci_eq_self
| Mathlib/Order/Interval/Set/ProjIcc.lean | 102 | 102 | theorem projIic_eq_self : projIic b x = ⟨b, le_rfl⟩ ↔ b ≤ x := by | simp [projIic, Subtype.ext_iff]
|
import Mathlib.Algebra.CharP.Invertible
import Mathlib.Analysis.NormedSpace.LinearIsometry
import Mathlib.Analysis.Normed.Group.AddTorsor
import Mathlib.Analysis.NormedSpace.Basic
import Mathlib.LinearAlgebra.AffineSpace.Restrict
import Mathlib.Tactic.FailIfNoProgress
#align_import analysis.normed_space.affine_isometry from "leanprover-community/mathlib"@"f0c8bf9245297a541f468be517f1bde6195105e9"
open Function Set
variable (𝕜 : Type*) {V V₁ V₁' V₂ V₃ V₄ : Type*} {P₁ P₁' : Type*} (P P₂ : Type*) {P₃ P₄ : Type*}
[NormedField 𝕜]
[SeminormedAddCommGroup V] [NormedSpace 𝕜 V] [PseudoMetricSpace P] [NormedAddTorsor V P]
[SeminormedAddCommGroup V₁] [NormedSpace 𝕜 V₁] [PseudoMetricSpace P₁] [NormedAddTorsor V₁ P₁]
[SeminormedAddCommGroup V₁'] [NormedSpace 𝕜 V₁'] [MetricSpace P₁'] [NormedAddTorsor V₁' P₁']
[SeminormedAddCommGroup V₂] [NormedSpace 𝕜 V₂] [PseudoMetricSpace P₂] [NormedAddTorsor V₂ P₂]
[SeminormedAddCommGroup V₃] [NormedSpace 𝕜 V₃] [PseudoMetricSpace P₃] [NormedAddTorsor V₃ P₃]
[SeminormedAddCommGroup V₄] [NormedSpace 𝕜 V₄] [PseudoMetricSpace P₄] [NormedAddTorsor V₄ P₄]
structure AffineIsometry extends P →ᵃ[𝕜] P₂ where
norm_map : ∀ x : V, ‖linear x‖ = ‖x‖
#align affine_isometry AffineIsometry
variable {𝕜 P P₂}
@[inherit_doc]
notation:25 -- `→ᵃᵢ` would be more consistent with the linear isometry notation, but it is uglier
P " →ᵃⁱ[" 𝕜:25 "] " P₂:0 => AffineIsometry 𝕜 P P₂
variable (𝕜 P P₂)
structure AffineIsometryEquiv extends P ≃ᵃ[𝕜] P₂ where
norm_map : ∀ x, ‖linear x‖ = ‖x‖
#align affine_isometry_equiv AffineIsometryEquiv
variable {𝕜 P P₂}
-- `≃ᵃᵢ` would be more consistent with the linear isometry equiv notation, but it is uglier
notation:25 P " ≃ᵃⁱ[" 𝕜:25 "] " P₂:0 => AffineIsometryEquiv 𝕜 P P₂
namespace AffineIsometryEquiv
variable (e : P ≃ᵃⁱ[𝕜] P₂)
protected def linearIsometryEquiv : V ≃ₗᵢ[𝕜] V₂ :=
{ e.linear with norm_map' := e.norm_map }
#align affine_isometry_equiv.linear_isometry_equiv AffineIsometryEquiv.linearIsometryEquiv
@[simp]
| Mathlib/Analysis/NormedSpace/AffineIsometry.lean | 329 | 331 | theorem linear_eq_linear_isometry : e.linear = e.linearIsometryEquiv.toLinearEquiv := by |
ext
rfl
|
import Mathlib.MeasureTheory.Measure.MeasureSpace
import Mathlib.MeasureTheory.Constructions.BorelSpace.Basic
#align_import measure_theory.measure.open_pos from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982"
open Topology ENNReal MeasureTheory
open Set Function Filter
namespace MeasureTheory
namespace Measure
section Basic
variable {X Y : Type*} [TopologicalSpace X] {m : MeasurableSpace X} [TopologicalSpace Y]
[T2Space Y] (μ ν : Measure X)
class IsOpenPosMeasure : Prop where
open_pos : ∀ U : Set X, IsOpen U → U.Nonempty → μ U ≠ 0
#align measure_theory.measure.is_open_pos_measure MeasureTheory.Measure.IsOpenPosMeasure
variable [IsOpenPosMeasure μ] {s U F : Set X} {x : X}
theorem _root_.IsOpen.measure_ne_zero (hU : IsOpen U) (hne : U.Nonempty) : μ U ≠ 0 :=
IsOpenPosMeasure.open_pos U hU hne
#align is_open.measure_ne_zero IsOpen.measure_ne_zero
theorem _root_.IsOpen.measure_pos (hU : IsOpen U) (hne : U.Nonempty) : 0 < μ U :=
(hU.measure_ne_zero μ hne).bot_lt
#align is_open.measure_pos IsOpen.measure_pos
instance (priority := 100) [Nonempty X] : NeZero μ :=
⟨measure_univ_pos.mp <| isOpen_univ.measure_pos μ univ_nonempty⟩
theorem _root_.IsOpen.measure_pos_iff (hU : IsOpen U) : 0 < μ U ↔ U.Nonempty :=
⟨fun h => nonempty_iff_ne_empty.2 fun he => h.ne' <| he.symm ▸ measure_empty, hU.measure_pos μ⟩
#align is_open.measure_pos_iff IsOpen.measure_pos_iff
theorem _root_.IsOpen.measure_eq_zero_iff (hU : IsOpen U) : μ U = 0 ↔ U = ∅ := by
simpa only [not_lt, nonpos_iff_eq_zero, not_nonempty_iff_eq_empty] using
not_congr (hU.measure_pos_iff μ)
#align is_open.measure_eq_zero_iff IsOpen.measure_eq_zero_iff
theorem measure_pos_of_nonempty_interior (h : (interior s).Nonempty) : 0 < μ s :=
(isOpen_interior.measure_pos μ h).trans_le (measure_mono interior_subset)
#align measure_theory.measure.measure_pos_of_nonempty_interior MeasureTheory.Measure.measure_pos_of_nonempty_interior
theorem measure_pos_of_mem_nhds (h : s ∈ 𝓝 x) : 0 < μ s :=
measure_pos_of_nonempty_interior _ ⟨x, mem_interior_iff_mem_nhds.2 h⟩
#align measure_theory.measure.measure_pos_of_mem_nhds MeasureTheory.Measure.measure_pos_of_mem_nhds
theorem isOpenPosMeasure_smul {c : ℝ≥0∞} (h : c ≠ 0) : IsOpenPosMeasure (c • μ) :=
⟨fun _U Uo Une => mul_ne_zero h (Uo.measure_ne_zero μ Une)⟩
#align measure_theory.measure.is_open_pos_measure_smul MeasureTheory.Measure.isOpenPosMeasure_smul
variable {μ ν}
protected theorem AbsolutelyContinuous.isOpenPosMeasure (h : μ ≪ ν) : IsOpenPosMeasure ν :=
⟨fun _U ho hne h₀ => ho.measure_ne_zero μ hne (h h₀)⟩
#align measure_theory.measure.absolutely_continuous.is_open_pos_measure MeasureTheory.Measure.AbsolutelyContinuous.isOpenPosMeasure
theorem _root_.LE.le.isOpenPosMeasure (h : μ ≤ ν) : IsOpenPosMeasure ν :=
h.absolutelyContinuous.isOpenPosMeasure
#align has_le.le.is_open_pos_measure LE.le.isOpenPosMeasure
theorem _root_.IsOpen.measure_zero_iff_eq_empty (hU : IsOpen U) :
μ U = 0 ↔ U = ∅ :=
⟨fun h ↦ (hU.measure_eq_zero_iff μ).mp h, fun h ↦ by simp [h]⟩
theorem _root_.IsOpen.ae_eq_empty_iff_eq (hU : IsOpen U) :
U =ᵐ[μ] (∅ : Set X) ↔ U = ∅ := by
rw [ae_eq_empty, hU.measure_zero_iff_eq_empty]
theorem _root_.IsOpen.eq_empty_of_measure_zero (hU : IsOpen U) (h₀ : μ U = 0) : U = ∅ :=
(hU.measure_eq_zero_iff μ).mp h₀
#align is_open.eq_empty_of_measure_zero IsOpen.eq_empty_of_measure_zero
theorem _root_.IsClosed.ae_eq_univ_iff_eq (hF : IsClosed F) :
F =ᵐ[μ] univ ↔ F = univ := by
refine ⟨fun h ↦ ?_, fun h ↦ by rw [h]⟩
rwa [ae_eq_univ, hF.isOpen_compl.measure_eq_zero_iff μ, compl_empty_iff] at h
theorem _root_.IsClosed.measure_eq_univ_iff_eq [OpensMeasurableSpace X] [IsFiniteMeasure μ]
(hF : IsClosed F) :
μ F = μ univ ↔ F = univ := by
rw [← ae_eq_univ_iff_measure_eq hF.measurableSet.nullMeasurableSet, hF.ae_eq_univ_iff_eq]
theorem _root_.IsClosed.measure_eq_one_iff_eq_univ [OpensMeasurableSpace X] [IsProbabilityMeasure μ]
(hF : IsClosed F) :
μ F = 1 ↔ F = univ := by
rw [← measure_univ (μ := μ), hF.measure_eq_univ_iff_eq]
theorem interior_eq_empty_of_null (hs : μ s = 0) : interior s = ∅ :=
isOpen_interior.eq_empty_of_measure_zero <| measure_mono_null interior_subset hs
#align measure_theory.measure.interior_eq_empty_of_null MeasureTheory.Measure.interior_eq_empty_of_null
| Mathlib/MeasureTheory/Measure/OpenPos.lean | 119 | 130 | theorem eqOn_open_of_ae_eq {f g : X → Y} (h : f =ᵐ[μ.restrict U] g) (hU : IsOpen U)
(hf : ContinuousOn f U) (hg : ContinuousOn g U) : EqOn f g U := by |
replace h := ae_imp_of_ae_restrict h
simp only [EventuallyEq, ae_iff, Classical.not_imp] at h
have : IsOpen (U ∩ { a | f a ≠ g a }) := by
refine isOpen_iff_mem_nhds.mpr fun a ha => inter_mem (hU.mem_nhds ha.1) ?_
rcases ha with ⟨ha : a ∈ U, ha' : (f a, g a) ∈ (diagonal Y)ᶜ⟩
exact
(hf.continuousAt (hU.mem_nhds ha)).prod_mk_nhds (hg.continuousAt (hU.mem_nhds ha))
(isClosed_diagonal.isOpen_compl.mem_nhds ha')
replace := (this.eq_empty_of_measure_zero h).le
exact fun x hx => Classical.not_not.1 fun h => this ⟨hx, h⟩
|
import Mathlib.Algebra.GroupWithZero.Indicator
import Mathlib.Topology.ContinuousOn
import Mathlib.Topology.Instances.ENNReal
#align_import topology.semicontinuous from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982"
open Topology ENNReal
open Set Function Filter
variable {α : Type*} [TopologicalSpace α] {β : Type*} [Preorder β] {f g : α → β} {x : α}
{s t : Set α} {y z : β}
def LowerSemicontinuousWithinAt (f : α → β) (s : Set α) (x : α) :=
∀ y < f x, ∀ᶠ x' in 𝓝[s] x, y < f x'
#align lower_semicontinuous_within_at LowerSemicontinuousWithinAt
def LowerSemicontinuousOn (f : α → β) (s : Set α) :=
∀ x ∈ s, LowerSemicontinuousWithinAt f s x
#align lower_semicontinuous_on LowerSemicontinuousOn
def LowerSemicontinuousAt (f : α → β) (x : α) :=
∀ y < f x, ∀ᶠ x' in 𝓝 x, y < f x'
#align lower_semicontinuous_at LowerSemicontinuousAt
def LowerSemicontinuous (f : α → β) :=
∀ x, LowerSemicontinuousAt f x
#align lower_semicontinuous LowerSemicontinuous
def UpperSemicontinuousWithinAt (f : α → β) (s : Set α) (x : α) :=
∀ y, f x < y → ∀ᶠ x' in 𝓝[s] x, f x' < y
#align upper_semicontinuous_within_at UpperSemicontinuousWithinAt
def UpperSemicontinuousOn (f : α → β) (s : Set α) :=
∀ x ∈ s, UpperSemicontinuousWithinAt f s x
#align upper_semicontinuous_on UpperSemicontinuousOn
def UpperSemicontinuousAt (f : α → β) (x : α) :=
∀ y, f x < y → ∀ᶠ x' in 𝓝 x, f x' < y
#align upper_semicontinuous_at UpperSemicontinuousAt
def UpperSemicontinuous (f : α → β) :=
∀ x, UpperSemicontinuousAt f x
#align upper_semicontinuous UpperSemicontinuous
theorem LowerSemicontinuousWithinAt.mono (h : LowerSemicontinuousWithinAt f s x) (hst : t ⊆ s) :
LowerSemicontinuousWithinAt f t x := fun y hy =>
Filter.Eventually.filter_mono (nhdsWithin_mono _ hst) (h y hy)
#align lower_semicontinuous_within_at.mono LowerSemicontinuousWithinAt.mono
theorem lowerSemicontinuousWithinAt_univ_iff :
LowerSemicontinuousWithinAt f univ x ↔ LowerSemicontinuousAt f x := by
simp [LowerSemicontinuousWithinAt, LowerSemicontinuousAt, nhdsWithin_univ]
#align lower_semicontinuous_within_at_univ_iff lowerSemicontinuousWithinAt_univ_iff
theorem LowerSemicontinuousAt.lowerSemicontinuousWithinAt (s : Set α)
(h : LowerSemicontinuousAt f x) : LowerSemicontinuousWithinAt f s x := fun y hy =>
Filter.Eventually.filter_mono nhdsWithin_le_nhds (h y hy)
#align lower_semicontinuous_at.lower_semicontinuous_within_at LowerSemicontinuousAt.lowerSemicontinuousWithinAt
theorem LowerSemicontinuousOn.lowerSemicontinuousWithinAt (h : LowerSemicontinuousOn f s)
(hx : x ∈ s) : LowerSemicontinuousWithinAt f s x :=
h x hx
#align lower_semicontinuous_on.lower_semicontinuous_within_at LowerSemicontinuousOn.lowerSemicontinuousWithinAt
theorem LowerSemicontinuousOn.mono (h : LowerSemicontinuousOn f s) (hst : t ⊆ s) :
LowerSemicontinuousOn f t := fun x hx => (h x (hst hx)).mono hst
#align lower_semicontinuous_on.mono LowerSemicontinuousOn.mono
theorem lowerSemicontinuousOn_univ_iff : LowerSemicontinuousOn f univ ↔ LowerSemicontinuous f := by
simp [LowerSemicontinuousOn, LowerSemicontinuous, lowerSemicontinuousWithinAt_univ_iff]
#align lower_semicontinuous_on_univ_iff lowerSemicontinuousOn_univ_iff
theorem LowerSemicontinuous.lowerSemicontinuousAt (h : LowerSemicontinuous f) (x : α) :
LowerSemicontinuousAt f x :=
h x
#align lower_semicontinuous.lower_semicontinuous_at LowerSemicontinuous.lowerSemicontinuousAt
theorem LowerSemicontinuous.lowerSemicontinuousWithinAt (h : LowerSemicontinuous f) (s : Set α)
(x : α) : LowerSemicontinuousWithinAt f s x :=
(h x).lowerSemicontinuousWithinAt s
#align lower_semicontinuous.lower_semicontinuous_within_at LowerSemicontinuous.lowerSemicontinuousWithinAt
theorem LowerSemicontinuous.lowerSemicontinuousOn (h : LowerSemicontinuous f) (s : Set α) :
LowerSemicontinuousOn f s := fun x _hx => h.lowerSemicontinuousWithinAt s x
#align lower_semicontinuous.lower_semicontinuous_on LowerSemicontinuous.lowerSemicontinuousOn
theorem lowerSemicontinuousWithinAt_const : LowerSemicontinuousWithinAt (fun _x => z) s x :=
fun _y hy => Filter.eventually_of_forall fun _x => hy
#align lower_semicontinuous_within_at_const lowerSemicontinuousWithinAt_const
theorem lowerSemicontinuousAt_const : LowerSemicontinuousAt (fun _x => z) x := fun _y hy =>
Filter.eventually_of_forall fun _x => hy
#align lower_semicontinuous_at_const lowerSemicontinuousAt_const
theorem lowerSemicontinuousOn_const : LowerSemicontinuousOn (fun _x => z) s := fun _x _hx =>
lowerSemicontinuousWithinAt_const
#align lower_semicontinuous_on_const lowerSemicontinuousOn_const
theorem lowerSemicontinuous_const : LowerSemicontinuous fun _x : α => z := fun _x =>
lowerSemicontinuousAt_const
#align lower_semicontinuous_const lowerSemicontinuous_const
section
variable [Zero β]
theorem IsOpen.lowerSemicontinuous_indicator (hs : IsOpen s) (hy : 0 ≤ y) :
LowerSemicontinuous (indicator s fun _x => y) := by
intro x z hz
by_cases h : x ∈ s <;> simp [h] at hz
· filter_upwards [hs.mem_nhds h]
simp (config := { contextual := true }) [hz]
· refine Filter.eventually_of_forall fun x' => ?_
by_cases h' : x' ∈ s <;> simp [h', hz.trans_le hy, hz]
#align is_open.lower_semicontinuous_indicator IsOpen.lowerSemicontinuous_indicator
theorem IsOpen.lowerSemicontinuousOn_indicator (hs : IsOpen s) (hy : 0 ≤ y) :
LowerSemicontinuousOn (indicator s fun _x => y) t :=
(hs.lowerSemicontinuous_indicator hy).lowerSemicontinuousOn t
#align is_open.lower_semicontinuous_on_indicator IsOpen.lowerSemicontinuousOn_indicator
theorem IsOpen.lowerSemicontinuousAt_indicator (hs : IsOpen s) (hy : 0 ≤ y) :
LowerSemicontinuousAt (indicator s fun _x => y) x :=
(hs.lowerSemicontinuous_indicator hy).lowerSemicontinuousAt x
#align is_open.lower_semicontinuous_at_indicator IsOpen.lowerSemicontinuousAt_indicator
theorem IsOpen.lowerSemicontinuousWithinAt_indicator (hs : IsOpen s) (hy : 0 ≤ y) :
LowerSemicontinuousWithinAt (indicator s fun _x => y) t x :=
(hs.lowerSemicontinuous_indicator hy).lowerSemicontinuousWithinAt t x
#align is_open.lower_semicontinuous_within_at_indicator IsOpen.lowerSemicontinuousWithinAt_indicator
theorem IsClosed.lowerSemicontinuous_indicator (hs : IsClosed s) (hy : y ≤ 0) :
LowerSemicontinuous (indicator s fun _x => y) := by
intro x z hz
by_cases h : x ∈ s <;> simp [h] at hz
· refine Filter.eventually_of_forall fun x' => ?_
by_cases h' : x' ∈ s <;> simp [h', hz, hz.trans_le hy]
· filter_upwards [hs.isOpen_compl.mem_nhds h]
simp (config := { contextual := true }) [hz]
#align is_closed.lower_semicontinuous_indicator IsClosed.lowerSemicontinuous_indicator
theorem IsClosed.lowerSemicontinuousOn_indicator (hs : IsClosed s) (hy : y ≤ 0) :
LowerSemicontinuousOn (indicator s fun _x => y) t :=
(hs.lowerSemicontinuous_indicator hy).lowerSemicontinuousOn t
#align is_closed.lower_semicontinuous_on_indicator IsClosed.lowerSemicontinuousOn_indicator
theorem IsClosed.lowerSemicontinuousAt_indicator (hs : IsClosed s) (hy : y ≤ 0) :
LowerSemicontinuousAt (indicator s fun _x => y) x :=
(hs.lowerSemicontinuous_indicator hy).lowerSemicontinuousAt x
#align is_closed.lower_semicontinuous_at_indicator IsClosed.lowerSemicontinuousAt_indicator
theorem IsClosed.lowerSemicontinuousWithinAt_indicator (hs : IsClosed s) (hy : y ≤ 0) :
LowerSemicontinuousWithinAt (indicator s fun _x => y) t x :=
(hs.lowerSemicontinuous_indicator hy).lowerSemicontinuousWithinAt t x
#align is_closed.lower_semicontinuous_within_at_indicator IsClosed.lowerSemicontinuousWithinAt_indicator
end
theorem lowerSemicontinuous_iff_isOpen_preimage :
LowerSemicontinuous f ↔ ∀ y, IsOpen (f ⁻¹' Ioi y) :=
⟨fun H y => isOpen_iff_mem_nhds.2 fun x hx => H x y hx, fun H _x y y_lt =>
IsOpen.mem_nhds (H y) y_lt⟩
#align lower_semicontinuous_iff_is_open_preimage lowerSemicontinuous_iff_isOpen_preimage
theorem LowerSemicontinuous.isOpen_preimage (hf : LowerSemicontinuous f) (y : β) :
IsOpen (f ⁻¹' Ioi y) :=
lowerSemicontinuous_iff_isOpen_preimage.1 hf y
#align lower_semicontinuous.is_open_preimage LowerSemicontinuous.isOpen_preimage
section
variable {γ : Type*} [LinearOrder γ]
theorem lowerSemicontinuous_iff_isClosed_preimage {f : α → γ} :
LowerSemicontinuous f ↔ ∀ y, IsClosed (f ⁻¹' Iic y) := by
rw [lowerSemicontinuous_iff_isOpen_preimage]
simp only [← isOpen_compl_iff, ← preimage_compl, compl_Iic]
#align lower_semicontinuous_iff_is_closed_preimage lowerSemicontinuous_iff_isClosed_preimage
theorem LowerSemicontinuous.isClosed_preimage {f : α → γ} (hf : LowerSemicontinuous f) (y : γ) :
IsClosed (f ⁻¹' Iic y) :=
lowerSemicontinuous_iff_isClosed_preimage.1 hf y
#align lower_semicontinuous.is_closed_preimage LowerSemicontinuous.isClosed_preimage
variable [TopologicalSpace γ] [OrderTopology γ]
theorem ContinuousWithinAt.lowerSemicontinuousWithinAt {f : α → γ} (h : ContinuousWithinAt f s x) :
LowerSemicontinuousWithinAt f s x := fun _y hy => h (Ioi_mem_nhds hy)
#align continuous_within_at.lower_semicontinuous_within_at ContinuousWithinAt.lowerSemicontinuousWithinAt
theorem ContinuousAt.lowerSemicontinuousAt {f : α → γ} (h : ContinuousAt f x) :
LowerSemicontinuousAt f x := fun _y hy => h (Ioi_mem_nhds hy)
#align continuous_at.lower_semicontinuous_at ContinuousAt.lowerSemicontinuousAt
theorem ContinuousOn.lowerSemicontinuousOn {f : α → γ} (h : ContinuousOn f s) :
LowerSemicontinuousOn f s := fun x hx => (h x hx).lowerSemicontinuousWithinAt
#align continuous_on.lower_semicontinuous_on ContinuousOn.lowerSemicontinuousOn
theorem Continuous.lowerSemicontinuous {f : α → γ} (h : Continuous f) : LowerSemicontinuous f :=
fun _x => h.continuousAt.lowerSemicontinuousAt
#align continuous.lower_semicontinuous Continuous.lowerSemicontinuous
end
section
variable {γ : Type*} [CompleteLinearOrder γ] [DenselyOrdered γ]
theorem lowerSemicontinuousWithinAt_iff_le_liminf {f : α → γ} :
LowerSemicontinuousWithinAt f s x ↔ f x ≤ liminf f (𝓝[s] x) := by
constructor
· intro hf; unfold LowerSemicontinuousWithinAt at hf
contrapose! hf
obtain ⟨y, lty, ylt⟩ := exists_between hf; use y
exact ⟨ylt, fun h => lty.not_le
(le_liminf_of_le (by isBoundedDefault) (h.mono fun _ hx => le_of_lt hx))⟩
exact fun hf y ylt => eventually_lt_of_lt_liminf (ylt.trans_le hf)
alias ⟨LowerSemicontinuousWithinAt.le_liminf, _⟩ := lowerSemicontinuousWithinAt_iff_le_liminf
theorem lowerSemicontinuousAt_iff_le_liminf {f : α → γ} :
LowerSemicontinuousAt f x ↔ f x ≤ liminf f (𝓝 x) := by
rw [← lowerSemicontinuousWithinAt_univ_iff, lowerSemicontinuousWithinAt_iff_le_liminf,
← nhdsWithin_univ]
alias ⟨LowerSemicontinuousAt.le_liminf, _⟩ := lowerSemicontinuousAt_iff_le_liminf
theorem lowerSemicontinuous_iff_le_liminf {f : α → γ} :
LowerSemicontinuous f ↔ ∀ x, f x ≤ liminf f (𝓝 x) := by
simp only [← lowerSemicontinuousAt_iff_le_liminf, LowerSemicontinuous]
alias ⟨LowerSemicontinuous.le_liminf, _⟩ := lowerSemicontinuous_iff_le_liminf
theorem lowerSemicontinuousOn_iff_le_liminf {f : α → γ} :
LowerSemicontinuousOn f s ↔ ∀ x ∈ s, f x ≤ liminf f (𝓝[s] x) := by
simp only [← lowerSemicontinuousWithinAt_iff_le_liminf, LowerSemicontinuousOn]
alias ⟨LowerSemicontinuousOn.le_liminf, _⟩ := lowerSemicontinuousOn_iff_le_liminf
variable [TopologicalSpace γ] [OrderTopology γ]
theorem lowerSemicontinuous_iff_isClosed_epigraph {f : α → γ} :
LowerSemicontinuous f ↔ IsClosed {p : α × γ | f p.1 ≤ p.2} := by
constructor
· rw [lowerSemicontinuous_iff_le_liminf, isClosed_iff_forall_filter]
rintro hf ⟨x, y⟩ F F_ne h h'
rw [nhds_prod_eq, le_prod] at h'
calc f x ≤ liminf f (𝓝 x) := hf x
_ ≤ liminf f (map Prod.fst F) := liminf_le_liminf_of_le h'.1
_ = liminf (f ∘ Prod.fst) F := (Filter.liminf_comp _ _ _).symm
_ ≤ liminf Prod.snd F := liminf_le_liminf <| by
simpa using (eventually_principal.2 fun (_ : α × γ) ↦ id).filter_mono h
_ = y := h'.2.liminf_eq
· rw [lowerSemicontinuous_iff_isClosed_preimage]
exact fun hf y ↦ hf.preimage (Continuous.Prod.mk_left y)
@[deprecated (since := "2024-03-02")]
alias lowerSemicontinuous_iff_IsClosed_epigraph := lowerSemicontinuous_iff_isClosed_epigraph
alias ⟨LowerSemicontinuous.isClosed_epigraph, _⟩ := lowerSemicontinuous_iff_isClosed_epigraph
@[deprecated (since := "2024-03-02")]
alias LowerSemicontinuous.IsClosed_epigraph := LowerSemicontinuous.isClosed_epigraph
end
section
variable {γ : Type*} [LinearOrder γ] [TopologicalSpace γ] [OrderTopology γ]
variable {δ : Type*} [LinearOrder δ] [TopologicalSpace δ] [OrderTopology δ]
variable {ι : Type*} [TopologicalSpace ι]
theorem ContinuousAt.comp_lowerSemicontinuousWithinAt {g : γ → δ} {f : α → γ}
(hg : ContinuousAt g (f x)) (hf : LowerSemicontinuousWithinAt f s x) (gmon : Monotone g) :
LowerSemicontinuousWithinAt (g ∘ f) s x := by
intro y hy
by_cases h : ∃ l, l < f x
· obtain ⟨z, zlt, hz⟩ : ∃ z < f x, Ioc z (f x) ⊆ g ⁻¹' Ioi y :=
exists_Ioc_subset_of_mem_nhds (hg (Ioi_mem_nhds hy)) h
filter_upwards [hf z zlt] with a ha
calc
y < g (min (f x) (f a)) := hz (by simp [zlt, ha, le_refl])
_ ≤ g (f a) := gmon (min_le_right _ _)
· simp only [not_exists, not_lt] at h
exact Filter.eventually_of_forall fun a => hy.trans_le (gmon (h (f a)))
#align continuous_at.comp_lower_semicontinuous_within_at ContinuousAt.comp_lowerSemicontinuousWithinAt
theorem ContinuousAt.comp_lowerSemicontinuousAt {g : γ → δ} {f : α → γ} (hg : ContinuousAt g (f x))
(hf : LowerSemicontinuousAt f x) (gmon : Monotone g) : LowerSemicontinuousAt (g ∘ f) x := by
simp only [← lowerSemicontinuousWithinAt_univ_iff] at hf ⊢
exact hg.comp_lowerSemicontinuousWithinAt hf gmon
#align continuous_at.comp_lower_semicontinuous_at ContinuousAt.comp_lowerSemicontinuousAt
theorem Continuous.comp_lowerSemicontinuousOn {g : γ → δ} {f : α → γ} (hg : Continuous g)
(hf : LowerSemicontinuousOn f s) (gmon : Monotone g) : LowerSemicontinuousOn (g ∘ f) s :=
fun x hx => hg.continuousAt.comp_lowerSemicontinuousWithinAt (hf x hx) gmon
#align continuous.comp_lower_semicontinuous_on Continuous.comp_lowerSemicontinuousOn
theorem Continuous.comp_lowerSemicontinuous {g : γ → δ} {f : α → γ} (hg : Continuous g)
(hf : LowerSemicontinuous f) (gmon : Monotone g) : LowerSemicontinuous (g ∘ f) := fun x =>
hg.continuousAt.comp_lowerSemicontinuousAt (hf x) gmon
#align continuous.comp_lower_semicontinuous Continuous.comp_lowerSemicontinuous
theorem ContinuousAt.comp_lowerSemicontinuousWithinAt_antitone {g : γ → δ} {f : α → γ}
(hg : ContinuousAt g (f x)) (hf : LowerSemicontinuousWithinAt f s x) (gmon : Antitone g) :
UpperSemicontinuousWithinAt (g ∘ f) s x :=
@ContinuousAt.comp_lowerSemicontinuousWithinAt α _ x s γ _ _ _ δᵒᵈ _ _ _ g f hg hf gmon
#align continuous_at.comp_lower_semicontinuous_within_at_antitone ContinuousAt.comp_lowerSemicontinuousWithinAt_antitone
theorem ContinuousAt.comp_lowerSemicontinuousAt_antitone {g : γ → δ} {f : α → γ}
(hg : ContinuousAt g (f x)) (hf : LowerSemicontinuousAt f x) (gmon : Antitone g) :
UpperSemicontinuousAt (g ∘ f) x :=
@ContinuousAt.comp_lowerSemicontinuousAt α _ x γ _ _ _ δᵒᵈ _ _ _ g f hg hf gmon
#align continuous_at.comp_lower_semicontinuous_at_antitone ContinuousAt.comp_lowerSemicontinuousAt_antitone
theorem Continuous.comp_lowerSemicontinuousOn_antitone {g : γ → δ} {f : α → γ} (hg : Continuous g)
(hf : LowerSemicontinuousOn f s) (gmon : Antitone g) : UpperSemicontinuousOn (g ∘ f) s :=
fun x hx => hg.continuousAt.comp_lowerSemicontinuousWithinAt_antitone (hf x hx) gmon
#align continuous.comp_lower_semicontinuous_on_antitone Continuous.comp_lowerSemicontinuousOn_antitone
theorem Continuous.comp_lowerSemicontinuous_antitone {g : γ → δ} {f : α → γ} (hg : Continuous g)
(hf : LowerSemicontinuous f) (gmon : Antitone g) : UpperSemicontinuous (g ∘ f) := fun x =>
hg.continuousAt.comp_lowerSemicontinuousAt_antitone (hf x) gmon
#align continuous.comp_lower_semicontinuous_antitone Continuous.comp_lowerSemicontinuous_antitone
theorem LowerSemicontinuousAt.comp_continuousAt {f : α → β} {g : ι → α} {x : ι}
(hf : LowerSemicontinuousAt f (g x)) (hg : ContinuousAt g x) :
LowerSemicontinuousAt (fun x ↦ f (g x)) x :=
fun _ lt ↦ hg.eventually (hf _ lt)
theorem LowerSemicontinuousAt.comp_continuousAt_of_eq {f : α → β} {g : ι → α} {y : α} {x : ι}
(hf : LowerSemicontinuousAt f y) (hg : ContinuousAt g x) (hy : g x = y) :
LowerSemicontinuousAt (fun x ↦ f (g x)) x := by
rw [← hy] at hf
exact comp_continuousAt hf hg
theorem LowerSemicontinuous.comp_continuous {f : α → β} {g : ι → α}
(hf : LowerSemicontinuous f) (hg : Continuous g) : LowerSemicontinuous fun x ↦ f (g x) :=
fun x ↦ (hf (g x)).comp_continuousAt hg.continuousAt
end
section
variable {ι : Type*} {γ : Type*} [LinearOrderedAddCommMonoid γ] [TopologicalSpace γ]
[OrderTopology γ]
theorem LowerSemicontinuousWithinAt.add' {f g : α → γ} (hf : LowerSemicontinuousWithinAt f s x)
(hg : LowerSemicontinuousWithinAt g s x)
(hcont : ContinuousAt (fun p : γ × γ => p.1 + p.2) (f x, g x)) :
LowerSemicontinuousWithinAt (fun z => f z + g z) s x := by
intro y hy
obtain ⟨u, v, u_open, xu, v_open, xv, h⟩ :
∃ u v : Set γ,
IsOpen u ∧ f x ∈ u ∧ IsOpen v ∧ g x ∈ v ∧ u ×ˢ v ⊆ { p : γ × γ | y < p.fst + p.snd } :=
mem_nhds_prod_iff'.1 (hcont (isOpen_Ioi.mem_nhds hy))
by_cases hx₁ : ∃ l, l < f x
· obtain ⟨z₁, z₁lt, h₁⟩ : ∃ z₁ < f x, Ioc z₁ (f x) ⊆ u :=
exists_Ioc_subset_of_mem_nhds (u_open.mem_nhds xu) hx₁
by_cases hx₂ : ∃ l, l < g x
· obtain ⟨z₂, z₂lt, h₂⟩ : ∃ z₂ < g x, Ioc z₂ (g x) ⊆ v :=
exists_Ioc_subset_of_mem_nhds (v_open.mem_nhds xv) hx₂
filter_upwards [hf z₁ z₁lt, hg z₂ z₂lt] with z h₁z h₂z
have A1 : min (f z) (f x) ∈ u := by
by_cases H : f z ≤ f x
· simp [H]
exact h₁ ⟨h₁z, H⟩
· simp [le_of_not_le H]
exact h₁ ⟨z₁lt, le_rfl⟩
have A2 : min (g z) (g x) ∈ v := by
by_cases H : g z ≤ g x
· simp [H]
exact h₂ ⟨h₂z, H⟩
· simp [le_of_not_le H]
exact h₂ ⟨z₂lt, le_rfl⟩
have : (min (f z) (f x), min (g z) (g x)) ∈ u ×ˢ v := ⟨A1, A2⟩
calc
y < min (f z) (f x) + min (g z) (g x) := h this
_ ≤ f z + g z := add_le_add (min_le_left _ _) (min_le_left _ _)
· simp only [not_exists, not_lt] at hx₂
filter_upwards [hf z₁ z₁lt] with z h₁z
have A1 : min (f z) (f x) ∈ u := by
by_cases H : f z ≤ f x
· simp [H]
exact h₁ ⟨h₁z, H⟩
· simp [le_of_not_le H]
exact h₁ ⟨z₁lt, le_rfl⟩
have : (min (f z) (f x), g x) ∈ u ×ˢ v := ⟨A1, xv⟩
calc
y < min (f z) (f x) + g x := h this
_ ≤ f z + g z := add_le_add (min_le_left _ _) (hx₂ (g z))
· simp only [not_exists, not_lt] at hx₁
by_cases hx₂ : ∃ l, l < g x
· obtain ⟨z₂, z₂lt, h₂⟩ : ∃ z₂ < g x, Ioc z₂ (g x) ⊆ v :=
exists_Ioc_subset_of_mem_nhds (v_open.mem_nhds xv) hx₂
filter_upwards [hg z₂ z₂lt] with z h₂z
have A2 : min (g z) (g x) ∈ v := by
by_cases H : g z ≤ g x
· simp [H]
exact h₂ ⟨h₂z, H⟩
· simp [le_of_not_le H]
exact h₂ ⟨z₂lt, le_rfl⟩
have : (f x, min (g z) (g x)) ∈ u ×ˢ v := ⟨xu, A2⟩
calc
y < f x + min (g z) (g x) := h this
_ ≤ f z + g z := add_le_add (hx₁ (f z)) (min_le_left _ _)
· simp only [not_exists, not_lt] at hx₁ hx₂
apply Filter.eventually_of_forall
intro z
have : (f x, g x) ∈ u ×ˢ v := ⟨xu, xv⟩
calc
y < f x + g x := h this
_ ≤ f z + g z := add_le_add (hx₁ (f z)) (hx₂ (g z))
#align lower_semicontinuous_within_at.add' LowerSemicontinuousWithinAt.add'
theorem LowerSemicontinuousAt.add' {f g : α → γ} (hf : LowerSemicontinuousAt f x)
(hg : LowerSemicontinuousAt g x)
(hcont : ContinuousAt (fun p : γ × γ => p.1 + p.2) (f x, g x)) :
LowerSemicontinuousAt (fun z => f z + g z) x := by
simp_rw [← lowerSemicontinuousWithinAt_univ_iff] at *
exact hf.add' hg hcont
#align lower_semicontinuous_at.add' LowerSemicontinuousAt.add'
theorem LowerSemicontinuousOn.add' {f g : α → γ} (hf : LowerSemicontinuousOn f s)
(hg : LowerSemicontinuousOn g s)
(hcont : ∀ x ∈ s, ContinuousAt (fun p : γ × γ => p.1 + p.2) (f x, g x)) :
LowerSemicontinuousOn (fun z => f z + g z) s := fun x hx =>
(hf x hx).add' (hg x hx) (hcont x hx)
#align lower_semicontinuous_on.add' LowerSemicontinuousOn.add'
theorem LowerSemicontinuous.add' {f g : α → γ} (hf : LowerSemicontinuous f)
(hg : LowerSemicontinuous g)
(hcont : ∀ x, ContinuousAt (fun p : γ × γ => p.1 + p.2) (f x, g x)) :
LowerSemicontinuous fun z => f z + g z := fun x => (hf x).add' (hg x) (hcont x)
#align lower_semicontinuous.add' LowerSemicontinuous.add'
variable [ContinuousAdd γ]
theorem LowerSemicontinuousWithinAt.add {f g : α → γ} (hf : LowerSemicontinuousWithinAt f s x)
(hg : LowerSemicontinuousWithinAt g s x) :
LowerSemicontinuousWithinAt (fun z => f z + g z) s x :=
hf.add' hg continuous_add.continuousAt
#align lower_semicontinuous_within_at.add LowerSemicontinuousWithinAt.add
theorem LowerSemicontinuousAt.add {f g : α → γ} (hf : LowerSemicontinuousAt f x)
(hg : LowerSemicontinuousAt g x) : LowerSemicontinuousAt (fun z => f z + g z) x :=
hf.add' hg continuous_add.continuousAt
#align lower_semicontinuous_at.add LowerSemicontinuousAt.add
theorem LowerSemicontinuousOn.add {f g : α → γ} (hf : LowerSemicontinuousOn f s)
(hg : LowerSemicontinuousOn g s) : LowerSemicontinuousOn (fun z => f z + g z) s :=
hf.add' hg fun _x _hx => continuous_add.continuousAt
#align lower_semicontinuous_on.add LowerSemicontinuousOn.add
theorem LowerSemicontinuous.add {f g : α → γ} (hf : LowerSemicontinuous f)
(hg : LowerSemicontinuous g) : LowerSemicontinuous fun z => f z + g z :=
hf.add' hg fun _x => continuous_add.continuousAt
#align lower_semicontinuous.add LowerSemicontinuous.add
theorem lowerSemicontinuousWithinAt_sum {f : ι → α → γ} {a : Finset ι}
(ha : ∀ i ∈ a, LowerSemicontinuousWithinAt (f i) s x) :
LowerSemicontinuousWithinAt (fun z => ∑ i ∈ a, f i z) s x := by
classical
induction' a using Finset.induction_on with i a ia IH
· exact lowerSemicontinuousWithinAt_const
· simp only [ia, Finset.sum_insert, not_false_iff]
exact
LowerSemicontinuousWithinAt.add (ha _ (Finset.mem_insert_self i a))
(IH fun j ja => ha j (Finset.mem_insert_of_mem ja))
#align lower_semicontinuous_within_at_sum lowerSemicontinuousWithinAt_sum
theorem lowerSemicontinuousAt_sum {f : ι → α → γ} {a : Finset ι}
(ha : ∀ i ∈ a, LowerSemicontinuousAt (f i) x) :
LowerSemicontinuousAt (fun z => ∑ i ∈ a, f i z) x := by
simp_rw [← lowerSemicontinuousWithinAt_univ_iff] at *
exact lowerSemicontinuousWithinAt_sum ha
#align lower_semicontinuous_at_sum lowerSemicontinuousAt_sum
theorem lowerSemicontinuousOn_sum {f : ι → α → γ} {a : Finset ι}
(ha : ∀ i ∈ a, LowerSemicontinuousOn (f i) s) :
LowerSemicontinuousOn (fun z => ∑ i ∈ a, f i z) s := fun x hx =>
lowerSemicontinuousWithinAt_sum fun i hi => ha i hi x hx
#align lower_semicontinuous_on_sum lowerSemicontinuousOn_sum
theorem lowerSemicontinuous_sum {f : ι → α → γ} {a : Finset ι}
(ha : ∀ i ∈ a, LowerSemicontinuous (f i)) : LowerSemicontinuous fun z => ∑ i ∈ a, f i z :=
fun x => lowerSemicontinuousAt_sum fun i hi => ha i hi x
#align lower_semicontinuous_sum lowerSemicontinuous_sum
end
section
variable {ι : Sort*} {δ δ' : Type*} [CompleteLinearOrder δ] [ConditionallyCompleteLinearOrder δ']
theorem lowerSemicontinuousWithinAt_ciSup {f : ι → α → δ'}
(bdd : ∀ᶠ y in 𝓝[s] x, BddAbove (range fun i => f i y))
(h : ∀ i, LowerSemicontinuousWithinAt (f i) s x) :
LowerSemicontinuousWithinAt (fun x' => ⨆ i, f i x') s x := by
cases isEmpty_or_nonempty ι
· simpa only [iSup_of_empty'] using lowerSemicontinuousWithinAt_const
· intro y hy
rcases exists_lt_of_lt_ciSup hy with ⟨i, hi⟩
filter_upwards [h i y hi, bdd] with y hy hy' using hy.trans_le (le_ciSup hy' i)
#align lower_semicontinuous_within_at_csupr lowerSemicontinuousWithinAt_ciSup
theorem lowerSemicontinuousWithinAt_iSup {f : ι → α → δ}
(h : ∀ i, LowerSemicontinuousWithinAt (f i) s x) :
LowerSemicontinuousWithinAt (fun x' => ⨆ i, f i x') s x :=
lowerSemicontinuousWithinAt_ciSup (by simp) h
#align lower_semicontinuous_within_at_supr lowerSemicontinuousWithinAt_iSup
theorem lowerSemicontinuousWithinAt_biSup {p : ι → Prop} {f : ∀ i, p i → α → δ}
(h : ∀ i hi, LowerSemicontinuousWithinAt (f i hi) s x) :
LowerSemicontinuousWithinAt (fun x' => ⨆ (i) (hi), f i hi x') s x :=
lowerSemicontinuousWithinAt_iSup fun i => lowerSemicontinuousWithinAt_iSup fun hi => h i hi
#align lower_semicontinuous_within_at_bsupr lowerSemicontinuousWithinAt_biSup
theorem lowerSemicontinuousAt_ciSup {f : ι → α → δ'}
(bdd : ∀ᶠ y in 𝓝 x, BddAbove (range fun i => f i y)) (h : ∀ i, LowerSemicontinuousAt (f i) x) :
LowerSemicontinuousAt (fun x' => ⨆ i, f i x') x := by
simp_rw [← lowerSemicontinuousWithinAt_univ_iff] at *
rw [← nhdsWithin_univ] at bdd
exact lowerSemicontinuousWithinAt_ciSup bdd h
#align lower_semicontinuous_at_csupr lowerSemicontinuousAt_ciSup
theorem lowerSemicontinuousAt_iSup {f : ι → α → δ} (h : ∀ i, LowerSemicontinuousAt (f i) x) :
LowerSemicontinuousAt (fun x' => ⨆ i, f i x') x :=
lowerSemicontinuousAt_ciSup (by simp) h
#align lower_semicontinuous_at_supr lowerSemicontinuousAt_iSup
theorem lowerSemicontinuousAt_biSup {p : ι → Prop} {f : ∀ i, p i → α → δ}
(h : ∀ i hi, LowerSemicontinuousAt (f i hi) x) :
LowerSemicontinuousAt (fun x' => ⨆ (i) (hi), f i hi x') x :=
lowerSemicontinuousAt_iSup fun i => lowerSemicontinuousAt_iSup fun hi => h i hi
#align lower_semicontinuous_at_bsupr lowerSemicontinuousAt_biSup
theorem lowerSemicontinuousOn_ciSup {f : ι → α → δ'}
(bdd : ∀ x ∈ s, BddAbove (range fun i => f i x)) (h : ∀ i, LowerSemicontinuousOn (f i) s) :
LowerSemicontinuousOn (fun x' => ⨆ i, f i x') s := fun x hx =>
lowerSemicontinuousWithinAt_ciSup (eventually_nhdsWithin_of_forall bdd) fun i => h i x hx
#align lower_semicontinuous_on_csupr lowerSemicontinuousOn_ciSup
theorem lowerSemicontinuousOn_iSup {f : ι → α → δ} (h : ∀ i, LowerSemicontinuousOn (f i) s) :
LowerSemicontinuousOn (fun x' => ⨆ i, f i x') s :=
lowerSemicontinuousOn_ciSup (by simp) h
#align lower_semicontinuous_on_supr lowerSemicontinuousOn_iSup
theorem lowerSemicontinuousOn_biSup {p : ι → Prop} {f : ∀ i, p i → α → δ}
(h : ∀ i hi, LowerSemicontinuousOn (f i hi) s) :
LowerSemicontinuousOn (fun x' => ⨆ (i) (hi), f i hi x') s :=
lowerSemicontinuousOn_iSup fun i => lowerSemicontinuousOn_iSup fun hi => h i hi
#align lower_semicontinuous_on_bsupr lowerSemicontinuousOn_biSup
theorem lowerSemicontinuous_ciSup {f : ι → α → δ'} (bdd : ∀ x, BddAbove (range fun i => f i x))
(h : ∀ i, LowerSemicontinuous (f i)) : LowerSemicontinuous fun x' => ⨆ i, f i x' := fun x =>
lowerSemicontinuousAt_ciSup (eventually_of_forall bdd) fun i => h i x
#align lower_semicontinuous_csupr lowerSemicontinuous_ciSup
theorem lowerSemicontinuous_iSup {f : ι → α → δ} (h : ∀ i, LowerSemicontinuous (f i)) :
LowerSemicontinuous fun x' => ⨆ i, f i x' :=
lowerSemicontinuous_ciSup (by simp) h
#align lower_semicontinuous_supr lowerSemicontinuous_iSup
theorem lowerSemicontinuous_biSup {p : ι → Prop} {f : ∀ i, p i → α → δ}
(h : ∀ i hi, LowerSemicontinuous (f i hi)) :
LowerSemicontinuous fun x' => ⨆ (i) (hi), f i hi x' :=
lowerSemicontinuous_iSup fun i => lowerSemicontinuous_iSup fun hi => h i hi
#align lower_semicontinuous_bsupr lowerSemicontinuous_biSup
end
section
variable {ι : Type*}
| Mathlib/Topology/Semicontinuous.lean | 727 | 732 | theorem lowerSemicontinuousWithinAt_tsum {f : ι → α → ℝ≥0∞}
(h : ∀ i, LowerSemicontinuousWithinAt (f i) s x) :
LowerSemicontinuousWithinAt (fun x' => ∑' i, f i x') s x := by |
simp_rw [ENNReal.tsum_eq_iSup_sum]
refine lowerSemicontinuousWithinAt_iSup fun b => ?_
exact lowerSemicontinuousWithinAt_sum fun i _hi => h i
|
import Mathlib.Analysis.SpecialFunctions.Trigonometric.Basic
import Mathlib.Analysis.Normed.Group.AddCircle
import Mathlib.Algebra.CharZero.Quotient
import Mathlib.Topology.Instances.Sign
#align_import analysis.special_functions.trigonometric.angle from "leanprover-community/mathlib"@"213b0cff7bc5ab6696ee07cceec80829ce42efec"
open Real
noncomputable section
namespace Real
-- Porting note: can't derive `NormedAddCommGroup, Inhabited`
def Angle : Type :=
AddCircle (2 * π)
#align real.angle Real.Angle
namespace Angle
-- Porting note (#10754): added due to missing instances due to no deriving
instance : NormedAddCommGroup Angle :=
inferInstanceAs (NormedAddCommGroup (AddCircle (2 * π)))
-- Porting note (#10754): added due to missing instances due to no deriving
instance : Inhabited Angle :=
inferInstanceAs (Inhabited (AddCircle (2 * π)))
-- Porting note (#10754): added due to missing instances due to no deriving
-- also, without this, a plain `QuotientAddGroup.mk`
-- causes coerced terms to be of type `ℝ ⧸ AddSubgroup.zmultiples (2 * π)`
@[coe]
protected def coe (r : ℝ) : Angle := QuotientAddGroup.mk r
instance : Coe ℝ Angle := ⟨Angle.coe⟩
instance : CircularOrder Real.Angle :=
QuotientAddGroup.circularOrder (hp' := ⟨by norm_num [pi_pos]⟩)
@[continuity]
theorem continuous_coe : Continuous ((↑) : ℝ → Angle) :=
continuous_quotient_mk'
#align real.angle.continuous_coe Real.Angle.continuous_coe
def coeHom : ℝ →+ Angle :=
QuotientAddGroup.mk' _
#align real.angle.coe_hom Real.Angle.coeHom
@[simp]
theorem coe_coeHom : (coeHom : ℝ → Angle) = ((↑) : ℝ → Angle) :=
rfl
#align real.angle.coe_coe_hom Real.Angle.coe_coeHom
@[elab_as_elim]
protected theorem induction_on {p : Angle → Prop} (θ : Angle) (h : ∀ x : ℝ, p x) : p θ :=
Quotient.inductionOn' θ h
#align real.angle.induction_on Real.Angle.induction_on
@[simp]
theorem coe_zero : ↑(0 : ℝ) = (0 : Angle) :=
rfl
#align real.angle.coe_zero Real.Angle.coe_zero
@[simp]
theorem coe_add (x y : ℝ) : ↑(x + y : ℝ) = (↑x + ↑y : Angle) :=
rfl
#align real.angle.coe_add Real.Angle.coe_add
@[simp]
theorem coe_neg (x : ℝ) : ↑(-x : ℝ) = -(↑x : Angle) :=
rfl
#align real.angle.coe_neg Real.Angle.coe_neg
@[simp]
theorem coe_sub (x y : ℝ) : ↑(x - y : ℝ) = (↑x - ↑y : Angle) :=
rfl
#align real.angle.coe_sub Real.Angle.coe_sub
theorem coe_nsmul (n : ℕ) (x : ℝ) : ↑(n • x : ℝ) = n • (↑x : Angle) :=
rfl
#align real.angle.coe_nsmul Real.Angle.coe_nsmul
theorem coe_zsmul (z : ℤ) (x : ℝ) : ↑(z • x : ℝ) = z • (↑x : Angle) :=
rfl
#align real.angle.coe_zsmul Real.Angle.coe_zsmul
@[simp, norm_cast]
theorem natCast_mul_eq_nsmul (x : ℝ) (n : ℕ) : ↑((n : ℝ) * x) = n • (↑x : Angle) := by
simpa only [nsmul_eq_mul] using coeHom.map_nsmul x n
#align real.angle.coe_nat_mul_eq_nsmul Real.Angle.natCast_mul_eq_nsmul
@[simp, norm_cast]
theorem intCast_mul_eq_zsmul (x : ℝ) (n : ℤ) : ↑((n : ℝ) * x : ℝ) = n • (↑x : Angle) := by
simpa only [zsmul_eq_mul] using coeHom.map_zsmul x n
#align real.angle.coe_int_mul_eq_zsmul Real.Angle.intCast_mul_eq_zsmul
@[deprecated (since := "2024-05-25")] alias coe_nat_mul_eq_nsmul := natCast_mul_eq_nsmul
@[deprecated (since := "2024-05-25")] alias coe_int_mul_eq_zsmul := intCast_mul_eq_zsmul
theorem angle_eq_iff_two_pi_dvd_sub {ψ θ : ℝ} : (θ : Angle) = ψ ↔ ∃ k : ℤ, θ - ψ = 2 * π * k := by
simp only [QuotientAddGroup.eq, AddSubgroup.zmultiples_eq_closure,
AddSubgroup.mem_closure_singleton, zsmul_eq_mul', (sub_eq_neg_add _ _).symm, eq_comm]
-- Porting note: added `rw`, `simp [Angle.coe, QuotientAddGroup.eq]` doesn't fire otherwise
rw [Angle.coe, Angle.coe, QuotientAddGroup.eq]
simp only [AddSubgroup.zmultiples_eq_closure,
AddSubgroup.mem_closure_singleton, zsmul_eq_mul', (sub_eq_neg_add _ _).symm, eq_comm]
#align real.angle.angle_eq_iff_two_pi_dvd_sub Real.Angle.angle_eq_iff_two_pi_dvd_sub
@[simp]
theorem coe_two_pi : ↑(2 * π : ℝ) = (0 : Angle) :=
angle_eq_iff_two_pi_dvd_sub.2 ⟨1, by rw [sub_zero, Int.cast_one, mul_one]⟩
#align real.angle.coe_two_pi Real.Angle.coe_two_pi
@[simp]
theorem neg_coe_pi : -(π : Angle) = π := by
rw [← coe_neg, angle_eq_iff_two_pi_dvd_sub]
use -1
simp [two_mul, sub_eq_add_neg]
#align real.angle.neg_coe_pi Real.Angle.neg_coe_pi
@[simp]
theorem two_nsmul_coe_div_two (θ : ℝ) : (2 : ℕ) • (↑(θ / 2) : Angle) = θ := by
rw [← coe_nsmul, two_nsmul, add_halves]
#align real.angle.two_nsmul_coe_div_two Real.Angle.two_nsmul_coe_div_two
@[simp]
theorem two_zsmul_coe_div_two (θ : ℝ) : (2 : ℤ) • (↑(θ / 2) : Angle) = θ := by
rw [← coe_zsmul, two_zsmul, add_halves]
#align real.angle.two_zsmul_coe_div_two Real.Angle.two_zsmul_coe_div_two
-- Porting note (#10618): @[simp] can prove it
theorem two_nsmul_neg_pi_div_two : (2 : ℕ) • (↑(-π / 2) : Angle) = π := by
rw [two_nsmul_coe_div_two, coe_neg, neg_coe_pi]
#align real.angle.two_nsmul_neg_pi_div_two Real.Angle.two_nsmul_neg_pi_div_two
-- Porting note (#10618): @[simp] can prove it
theorem two_zsmul_neg_pi_div_two : (2 : ℤ) • (↑(-π / 2) : Angle) = π := by
rw [two_zsmul, ← two_nsmul, two_nsmul_neg_pi_div_two]
#align real.angle.two_zsmul_neg_pi_div_two Real.Angle.two_zsmul_neg_pi_div_two
theorem sub_coe_pi_eq_add_coe_pi (θ : Angle) : θ - π = θ + π := by
rw [sub_eq_add_neg, neg_coe_pi]
#align real.angle.sub_coe_pi_eq_add_coe_pi Real.Angle.sub_coe_pi_eq_add_coe_pi
@[simp]
theorem two_nsmul_coe_pi : (2 : ℕ) • (π : Angle) = 0 := by simp [← natCast_mul_eq_nsmul]
#align real.angle.two_nsmul_coe_pi Real.Angle.two_nsmul_coe_pi
@[simp]
theorem two_zsmul_coe_pi : (2 : ℤ) • (π : Angle) = 0 := by simp [← intCast_mul_eq_zsmul]
#align real.angle.two_zsmul_coe_pi Real.Angle.two_zsmul_coe_pi
@[simp]
theorem coe_pi_add_coe_pi : (π : Real.Angle) + π = 0 := by rw [← two_nsmul, two_nsmul_coe_pi]
#align real.angle.coe_pi_add_coe_pi Real.Angle.coe_pi_add_coe_pi
theorem zsmul_eq_iff {ψ θ : Angle} {z : ℤ} (hz : z ≠ 0) :
z • ψ = z • θ ↔ ∃ k : Fin z.natAbs, ψ = θ + (k : ℕ) • (2 * π / z : ℝ) :=
QuotientAddGroup.zmultiples_zsmul_eq_zsmul_iff hz
#align real.angle.zsmul_eq_iff Real.Angle.zsmul_eq_iff
theorem nsmul_eq_iff {ψ θ : Angle} {n : ℕ} (hz : n ≠ 0) :
n • ψ = n • θ ↔ ∃ k : Fin n, ψ = θ + (k : ℕ) • (2 * π / n : ℝ) :=
QuotientAddGroup.zmultiples_nsmul_eq_nsmul_iff hz
#align real.angle.nsmul_eq_iff Real.Angle.nsmul_eq_iff
theorem two_zsmul_eq_iff {ψ θ : Angle} : (2 : ℤ) • ψ = (2 : ℤ) • θ ↔ ψ = θ ∨ ψ = θ + ↑π := by
-- Porting note: no `Int.natAbs_bit0` anymore
have : Int.natAbs 2 = 2 := rfl
rw [zsmul_eq_iff two_ne_zero, this, Fin.exists_fin_two, Fin.val_zero,
Fin.val_one, zero_smul, add_zero, one_smul, Int.cast_two,
mul_div_cancel_left₀ (_ : ℝ) two_ne_zero]
#align real.angle.two_zsmul_eq_iff Real.Angle.two_zsmul_eq_iff
theorem two_nsmul_eq_iff {ψ θ : Angle} : (2 : ℕ) • ψ = (2 : ℕ) • θ ↔ ψ = θ ∨ ψ = θ + ↑π := by
simp_rw [← natCast_zsmul, Nat.cast_ofNat, two_zsmul_eq_iff]
#align real.angle.two_nsmul_eq_iff Real.Angle.two_nsmul_eq_iff
theorem two_nsmul_eq_zero_iff {θ : Angle} : (2 : ℕ) • θ = 0 ↔ θ = 0 ∨ θ = π := by
convert two_nsmul_eq_iff <;> simp
#align real.angle.two_nsmul_eq_zero_iff Real.Angle.two_nsmul_eq_zero_iff
theorem two_nsmul_ne_zero_iff {θ : Angle} : (2 : ℕ) • θ ≠ 0 ↔ θ ≠ 0 ∧ θ ≠ π := by
rw [← not_or, ← two_nsmul_eq_zero_iff]
#align real.angle.two_nsmul_ne_zero_iff Real.Angle.two_nsmul_ne_zero_iff
theorem two_zsmul_eq_zero_iff {θ : Angle} : (2 : ℤ) • θ = 0 ↔ θ = 0 ∨ θ = π := by
simp_rw [two_zsmul, ← two_nsmul, two_nsmul_eq_zero_iff]
#align real.angle.two_zsmul_eq_zero_iff Real.Angle.two_zsmul_eq_zero_iff
theorem two_zsmul_ne_zero_iff {θ : Angle} : (2 : ℤ) • θ ≠ 0 ↔ θ ≠ 0 ∧ θ ≠ π := by
rw [← not_or, ← two_zsmul_eq_zero_iff]
#align real.angle.two_zsmul_ne_zero_iff Real.Angle.two_zsmul_ne_zero_iff
theorem eq_neg_self_iff {θ : Angle} : θ = -θ ↔ θ = 0 ∨ θ = π := by
rw [← add_eq_zero_iff_eq_neg, ← two_nsmul, two_nsmul_eq_zero_iff]
#align real.angle.eq_neg_self_iff Real.Angle.eq_neg_self_iff
theorem ne_neg_self_iff {θ : Angle} : θ ≠ -θ ↔ θ ≠ 0 ∧ θ ≠ π := by
rw [← not_or, ← eq_neg_self_iff.not]
#align real.angle.ne_neg_self_iff Real.Angle.ne_neg_self_iff
theorem neg_eq_self_iff {θ : Angle} : -θ = θ ↔ θ = 0 ∨ θ = π := by rw [eq_comm, eq_neg_self_iff]
#align real.angle.neg_eq_self_iff Real.Angle.neg_eq_self_iff
theorem neg_ne_self_iff {θ : Angle} : -θ ≠ θ ↔ θ ≠ 0 ∧ θ ≠ π := by
rw [← not_or, ← neg_eq_self_iff.not]
#align real.angle.neg_ne_self_iff Real.Angle.neg_ne_self_iff
theorem two_nsmul_eq_pi_iff {θ : Angle} : (2 : ℕ) • θ = π ↔ θ = (π / 2 : ℝ) ∨ θ = (-π / 2 : ℝ) := by
have h : (π : Angle) = ((2 : ℕ) • (π / 2 : ℝ) :) := by rw [two_nsmul, add_halves]
nth_rw 1 [h]
rw [coe_nsmul, two_nsmul_eq_iff]
-- Porting note: `congr` didn't simplify the goal of iff of `Or`s
convert Iff.rfl
rw [add_comm, ← coe_add, ← sub_eq_zero, ← coe_sub, neg_div, ← neg_sub, sub_neg_eq_add, add_assoc,
add_halves, ← two_mul, coe_neg, coe_two_pi, neg_zero]
#align real.angle.two_nsmul_eq_pi_iff Real.Angle.two_nsmul_eq_pi_iff
theorem two_zsmul_eq_pi_iff {θ : Angle} : (2 : ℤ) • θ = π ↔ θ = (π / 2 : ℝ) ∨ θ = (-π / 2 : ℝ) := by
rw [two_zsmul, ← two_nsmul, two_nsmul_eq_pi_iff]
#align real.angle.two_zsmul_eq_pi_iff Real.Angle.two_zsmul_eq_pi_iff
theorem cos_eq_iff_coe_eq_or_eq_neg {θ ψ : ℝ} :
cos θ = cos ψ ↔ (θ : Angle) = ψ ∨ (θ : Angle) = -ψ := by
constructor
· intro Hcos
rw [← sub_eq_zero, cos_sub_cos, mul_eq_zero, mul_eq_zero, neg_eq_zero,
eq_false (two_ne_zero' ℝ), false_or_iff, sin_eq_zero_iff, sin_eq_zero_iff] at Hcos
rcases Hcos with (⟨n, hn⟩ | ⟨n, hn⟩)
· right
rw [eq_div_iff_mul_eq (two_ne_zero' ℝ), ← sub_eq_iff_eq_add] at hn
rw [← hn, coe_sub, eq_neg_iff_add_eq_zero, sub_add_cancel, mul_assoc, intCast_mul_eq_zsmul,
mul_comm, coe_two_pi, zsmul_zero]
· left
rw [eq_div_iff_mul_eq (two_ne_zero' ℝ), eq_sub_iff_add_eq] at hn
rw [← hn, coe_add, mul_assoc, intCast_mul_eq_zsmul, mul_comm, coe_two_pi, zsmul_zero,
zero_add]
· rw [angle_eq_iff_two_pi_dvd_sub, ← coe_neg, angle_eq_iff_two_pi_dvd_sub]
rintro (⟨k, H⟩ | ⟨k, H⟩)
· rw [← sub_eq_zero, cos_sub_cos, H, mul_assoc 2 π k, mul_div_cancel_left₀ _ (two_ne_zero' ℝ),
mul_comm π _, sin_int_mul_pi, mul_zero]
rw [← sub_eq_zero, cos_sub_cos, ← sub_neg_eq_add, H, mul_assoc 2 π k,
mul_div_cancel_left₀ _ (two_ne_zero' ℝ), mul_comm π _, sin_int_mul_pi, mul_zero,
zero_mul]
#align real.angle.cos_eq_iff_coe_eq_or_eq_neg Real.Angle.cos_eq_iff_coe_eq_or_eq_neg
theorem sin_eq_iff_coe_eq_or_add_eq_pi {θ ψ : ℝ} :
sin θ = sin ψ ↔ (θ : Angle) = ψ ∨ (θ : Angle) + ψ = π := by
constructor
· intro Hsin
rw [← cos_pi_div_two_sub, ← cos_pi_div_two_sub] at Hsin
cases' cos_eq_iff_coe_eq_or_eq_neg.mp Hsin with h h
· left
rw [coe_sub, coe_sub] at h
exact sub_right_inj.1 h
right
rw [coe_sub, coe_sub, eq_neg_iff_add_eq_zero, add_sub, sub_add_eq_add_sub, ← coe_add,
add_halves, sub_sub, sub_eq_zero] at h
exact h.symm
· rw [angle_eq_iff_two_pi_dvd_sub, ← eq_sub_iff_add_eq, ← coe_sub, angle_eq_iff_two_pi_dvd_sub]
rintro (⟨k, H⟩ | ⟨k, H⟩)
· rw [← sub_eq_zero, sin_sub_sin, H, mul_assoc 2 π k, mul_div_cancel_left₀ _ (two_ne_zero' ℝ),
mul_comm π _, sin_int_mul_pi, mul_zero, zero_mul]
have H' : θ + ψ = 2 * k * π + π := by
rwa [← sub_add, sub_add_eq_add_sub, sub_eq_iff_eq_add, mul_assoc, mul_comm π _, ←
mul_assoc] at H
rw [← sub_eq_zero, sin_sub_sin, H', add_div, mul_assoc 2 _ π,
mul_div_cancel_left₀ _ (two_ne_zero' ℝ), cos_add_pi_div_two, sin_int_mul_pi, neg_zero,
mul_zero]
#align real.angle.sin_eq_iff_coe_eq_or_add_eq_pi Real.Angle.sin_eq_iff_coe_eq_or_add_eq_pi
theorem cos_sin_inj {θ ψ : ℝ} (Hcos : cos θ = cos ψ) (Hsin : sin θ = sin ψ) : (θ : Angle) = ψ := by
cases' cos_eq_iff_coe_eq_or_eq_neg.mp Hcos with hc hc; · exact hc
cases' sin_eq_iff_coe_eq_or_add_eq_pi.mp Hsin with hs hs; · exact hs
rw [eq_neg_iff_add_eq_zero, hs] at hc
obtain ⟨n, hn⟩ : ∃ n, n • _ = _ := QuotientAddGroup.leftRel_apply.mp (Quotient.exact' hc)
rw [← neg_one_mul, add_zero, ← sub_eq_zero, zsmul_eq_mul, ← mul_assoc, ← sub_mul, mul_eq_zero,
eq_false (ne_of_gt pi_pos), or_false_iff, sub_neg_eq_add, ← Int.cast_zero, ← Int.cast_one,
← Int.cast_ofNat, ← Int.cast_mul, ← Int.cast_add, Int.cast_inj] at hn
have : (n * 2 + 1) % (2 : ℤ) = 0 % (2 : ℤ) := congr_arg (· % (2 : ℤ)) hn
rw [add_comm, Int.add_mul_emod_self] at this
exact absurd this one_ne_zero
#align real.angle.cos_sin_inj Real.Angle.cos_sin_inj
def sin (θ : Angle) : ℝ :=
sin_periodic.lift θ
#align real.angle.sin Real.Angle.sin
@[simp]
theorem sin_coe (x : ℝ) : sin (x : Angle) = Real.sin x :=
rfl
#align real.angle.sin_coe Real.Angle.sin_coe
@[continuity]
theorem continuous_sin : Continuous sin :=
Real.continuous_sin.quotient_liftOn' _
#align real.angle.continuous_sin Real.Angle.continuous_sin
def cos (θ : Angle) : ℝ :=
cos_periodic.lift θ
#align real.angle.cos Real.Angle.cos
@[simp]
theorem cos_coe (x : ℝ) : cos (x : Angle) = Real.cos x :=
rfl
#align real.angle.cos_coe Real.Angle.cos_coe
@[continuity]
theorem continuous_cos : Continuous cos :=
Real.continuous_cos.quotient_liftOn' _
#align real.angle.continuous_cos Real.Angle.continuous_cos
theorem cos_eq_real_cos_iff_eq_or_eq_neg {θ : Angle} {ψ : ℝ} :
cos θ = Real.cos ψ ↔ θ = ψ ∨ θ = -ψ := by
induction θ using Real.Angle.induction_on
exact cos_eq_iff_coe_eq_or_eq_neg
#align real.angle.cos_eq_real_cos_iff_eq_or_eq_neg Real.Angle.cos_eq_real_cos_iff_eq_or_eq_neg
theorem cos_eq_iff_eq_or_eq_neg {θ ψ : Angle} : cos θ = cos ψ ↔ θ = ψ ∨ θ = -ψ := by
induction ψ using Real.Angle.induction_on
exact cos_eq_real_cos_iff_eq_or_eq_neg
#align real.angle.cos_eq_iff_eq_or_eq_neg Real.Angle.cos_eq_iff_eq_or_eq_neg
theorem sin_eq_real_sin_iff_eq_or_add_eq_pi {θ : Angle} {ψ : ℝ} :
sin θ = Real.sin ψ ↔ θ = ψ ∨ θ + ψ = π := by
induction θ using Real.Angle.induction_on
exact sin_eq_iff_coe_eq_or_add_eq_pi
#align real.angle.sin_eq_real_sin_iff_eq_or_add_eq_pi Real.Angle.sin_eq_real_sin_iff_eq_or_add_eq_pi
theorem sin_eq_iff_eq_or_add_eq_pi {θ ψ : Angle} : sin θ = sin ψ ↔ θ = ψ ∨ θ + ψ = π := by
induction ψ using Real.Angle.induction_on
exact sin_eq_real_sin_iff_eq_or_add_eq_pi
#align real.angle.sin_eq_iff_eq_or_add_eq_pi Real.Angle.sin_eq_iff_eq_or_add_eq_pi
@[simp]
theorem sin_zero : sin (0 : Angle) = 0 := by rw [← coe_zero, sin_coe, Real.sin_zero]
#align real.angle.sin_zero Real.Angle.sin_zero
-- Porting note (#10618): @[simp] can prove it
theorem sin_coe_pi : sin (π : Angle) = 0 := by rw [sin_coe, Real.sin_pi]
#align real.angle.sin_coe_pi Real.Angle.sin_coe_pi
theorem sin_eq_zero_iff {θ : Angle} : sin θ = 0 ↔ θ = 0 ∨ θ = π := by
nth_rw 1 [← sin_zero]
rw [sin_eq_iff_eq_or_add_eq_pi]
simp
#align real.angle.sin_eq_zero_iff Real.Angle.sin_eq_zero_iff
theorem sin_ne_zero_iff {θ : Angle} : sin θ ≠ 0 ↔ θ ≠ 0 ∧ θ ≠ π := by
rw [← not_or, ← sin_eq_zero_iff]
#align real.angle.sin_ne_zero_iff Real.Angle.sin_ne_zero_iff
@[simp]
theorem sin_neg (θ : Angle) : sin (-θ) = -sin θ := by
induction θ using Real.Angle.induction_on
exact Real.sin_neg _
#align real.angle.sin_neg Real.Angle.sin_neg
theorem sin_antiperiodic : Function.Antiperiodic sin (π : Angle) := by
intro θ
induction θ using Real.Angle.induction_on
exact Real.sin_antiperiodic _
#align real.angle.sin_antiperiodic Real.Angle.sin_antiperiodic
@[simp]
theorem sin_add_pi (θ : Angle) : sin (θ + π) = -sin θ :=
sin_antiperiodic θ
#align real.angle.sin_add_pi Real.Angle.sin_add_pi
@[simp]
theorem sin_sub_pi (θ : Angle) : sin (θ - π) = -sin θ :=
sin_antiperiodic.sub_eq θ
#align real.angle.sin_sub_pi Real.Angle.sin_sub_pi
@[simp]
| Mathlib/Analysis/SpecialFunctions/Trigonometric/Angle.lean | 398 | 398 | theorem cos_zero : cos (0 : Angle) = 1 := by | rw [← coe_zero, cos_coe, Real.cos_zero]
|
import Mathlib.Data.Matrix.Basic
import Mathlib.Data.Matrix.RowCol
import Mathlib.Data.Fin.VecNotation
import Mathlib.Tactic.FinCases
#align_import data.matrix.notation from "leanprover-community/mathlib"@"a99f85220eaf38f14f94e04699943e185a5e1d1a"
namespace Matrix
universe u uₘ uₙ uₒ
variable {α : Type u} {o n m : ℕ} {m' : Type uₘ} {n' : Type uₙ} {o' : Type uₒ}
open Matrix
variable (a b : ℕ)
instance repr [Repr α] : Repr (Matrix (Fin m) (Fin n) α) where
reprPrec f _p :=
(Std.Format.bracket "!![" · "]") <|
(Std.Format.joinSep · (";" ++ Std.Format.line)) <|
(List.finRange m).map fun i =>
Std.Format.fill <| -- wrap line in a single place rather than all at once
(Std.Format.joinSep · ("," ++ Std.Format.line)) <|
(List.finRange n).map fun j => _root_.repr (f i j)
#align matrix.has_repr Matrix.repr
@[simp]
theorem cons_val' (v : n' → α) (B : Fin m → n' → α) (i j) :
vecCons v B i j = vecCons (v j) (fun i => B i j) i := by refine Fin.cases ?_ ?_ i <;> simp
#align matrix.cons_val' Matrix.cons_val'
@[simp, nolint simpNF] -- Porting note: LHS does not simplify.
theorem head_val' (B : Fin m.succ → n' → α) (j : n') : (vecHead fun i => B i j) = vecHead B j :=
rfl
#align matrix.head_val' Matrix.head_val'
@[simp, nolint simpNF] -- Porting note: LHS does not simplify.
theorem tail_val' (B : Fin m.succ → n' → α) (j : n') :
(vecTail fun i => B i j) = fun i => vecTail B i j := rfl
#align matrix.tail_val' Matrix.tail_val'
section DotProduct
variable [AddCommMonoid α] [Mul α]
@[simp]
theorem dotProduct_empty (v w : Fin 0 → α) : dotProduct v w = 0 :=
Finset.sum_empty
#align matrix.dot_product_empty Matrix.dotProduct_empty
@[simp]
theorem cons_dotProduct (x : α) (v : Fin n → α) (w : Fin n.succ → α) :
dotProduct (vecCons x v) w = x * vecHead w + dotProduct v (vecTail w) := by
simp [dotProduct, Fin.sum_univ_succ, vecHead, vecTail]
#align matrix.cons_dot_product Matrix.cons_dotProduct
@[simp]
| Mathlib/Data/Matrix/Notation.lean | 168 | 170 | theorem dotProduct_cons (v : Fin n.succ → α) (x : α) (w : Fin n → α) :
dotProduct v (vecCons x w) = vecHead v * x + dotProduct (vecTail v) w := by |
simp [dotProduct, Fin.sum_univ_succ, vecHead, vecTail]
|
import Mathlib.Order.Interval.Set.Basic
import Mathlib.Order.Hom.Set
#align_import data.set.intervals.order_iso from "leanprover-community/mathlib"@"d012cd09a9b256d870751284dd6a29882b0be105"
open Set
namespace OrderIso
section Preorder
variable {α β : Type*} [Preorder α] [Preorder β]
@[simp]
theorem preimage_Iic (e : α ≃o β) (b : β) : e ⁻¹' Iic b = Iic (e.symm b) := by
ext x
simp [← e.le_iff_le]
#align order_iso.preimage_Iic OrderIso.preimage_Iic
@[simp]
theorem preimage_Ici (e : α ≃o β) (b : β) : e ⁻¹' Ici b = Ici (e.symm b) := by
ext x
simp [← e.le_iff_le]
#align order_iso.preimage_Ici OrderIso.preimage_Ici
@[simp]
theorem preimage_Iio (e : α ≃o β) (b : β) : e ⁻¹' Iio b = Iio (e.symm b) := by
ext x
simp [← e.lt_iff_lt]
#align order_iso.preimage_Iio OrderIso.preimage_Iio
@[simp]
theorem preimage_Ioi (e : α ≃o β) (b : β) : e ⁻¹' Ioi b = Ioi (e.symm b) := by
ext x
simp [← e.lt_iff_lt]
#align order_iso.preimage_Ioi OrderIso.preimage_Ioi
@[simp]
theorem preimage_Icc (e : α ≃o β) (a b : β) : e ⁻¹' Icc a b = Icc (e.symm a) (e.symm b) := by
simp [← Ici_inter_Iic]
#align order_iso.preimage_Icc OrderIso.preimage_Icc
@[simp]
theorem preimage_Ico (e : α ≃o β) (a b : β) : e ⁻¹' Ico a b = Ico (e.symm a) (e.symm b) := by
simp [← Ici_inter_Iio]
#align order_iso.preimage_Ico OrderIso.preimage_Ico
@[simp]
theorem preimage_Ioc (e : α ≃o β) (a b : β) : e ⁻¹' Ioc a b = Ioc (e.symm a) (e.symm b) := by
simp [← Ioi_inter_Iic]
#align order_iso.preimage_Ioc OrderIso.preimage_Ioc
@[simp]
theorem preimage_Ioo (e : α ≃o β) (a b : β) : e ⁻¹' Ioo a b = Ioo (e.symm a) (e.symm b) := by
simp [← Ioi_inter_Iio]
#align order_iso.preimage_Ioo OrderIso.preimage_Ioo
@[simp]
theorem image_Iic (e : α ≃o β) (a : α) : e '' Iic a = Iic (e a) := by
rw [e.image_eq_preimage, e.symm.preimage_Iic, e.symm_symm]
#align order_iso.image_Iic OrderIso.image_Iic
@[simp]
theorem image_Ici (e : α ≃o β) (a : α) : e '' Ici a = Ici (e a) :=
e.dual.image_Iic a
#align order_iso.image_Ici OrderIso.image_Ici
@[simp]
theorem image_Iio (e : α ≃o β) (a : α) : e '' Iio a = Iio (e a) := by
rw [e.image_eq_preimage, e.symm.preimage_Iio, e.symm_symm]
#align order_iso.image_Iio OrderIso.image_Iio
@[simp]
theorem image_Ioi (e : α ≃o β) (a : α) : e '' Ioi a = Ioi (e a) :=
e.dual.image_Iio a
#align order_iso.image_Ioi OrderIso.image_Ioi
@[simp]
theorem image_Ioo (e : α ≃o β) (a b : α) : e '' Ioo a b = Ioo (e a) (e b) := by
rw [e.image_eq_preimage, e.symm.preimage_Ioo, e.symm_symm]
#align order_iso.image_Ioo OrderIso.image_Ioo
@[simp]
theorem image_Ioc (e : α ≃o β) (a b : α) : e '' Ioc a b = Ioc (e a) (e b) := by
rw [e.image_eq_preimage, e.symm.preimage_Ioc, e.symm_symm]
#align order_iso.image_Ioc OrderIso.image_Ioc
@[simp]
theorem image_Ico (e : α ≃o β) (a b : α) : e '' Ico a b = Ico (e a) (e b) := by
rw [e.image_eq_preimage, e.symm.preimage_Ico, e.symm_symm]
#align order_iso.image_Ico OrderIso.image_Ico
@[simp]
| Mathlib/Order/Interval/Set/OrderIso.lean | 103 | 104 | theorem image_Icc (e : α ≃o β) (a b : α) : e '' Icc a b = Icc (e a) (e b) := by |
rw [e.image_eq_preimage, e.symm.preimage_Icc, e.symm_symm]
|
import Mathlib.Topology.Order.Basic
open Set Filter OrderDual
open scoped Topology
section OrderClosedTopology
variable {α : Type*} [LinearOrder α] [TopologicalSpace α] [OrderClosedTopology α] {a b c d : α}
@[simp] theorem nhdsSet_Ioi : 𝓝ˢ (Ioi a) = 𝓟 (Ioi a) := isOpen_Ioi.nhdsSet_eq
@[simp] theorem nhdsSet_Iio : 𝓝ˢ (Iio a) = 𝓟 (Iio a) := isOpen_Iio.nhdsSet_eq
@[simp] theorem nhdsSet_Ioo : 𝓝ˢ (Ioo a b) = 𝓟 (Ioo a b) := isOpen_Ioo.nhdsSet_eq
theorem nhdsSet_Ici : 𝓝ˢ (Ici a) = 𝓝 a ⊔ 𝓟 (Ioi a) := by
rw [← Ioi_insert, nhdsSet_insert, nhdsSet_Ioi]
theorem nhdsSet_Iic : 𝓝ˢ (Iic a) = 𝓝 a ⊔ 𝓟 (Iio a) := nhdsSet_Ici (α := αᵒᵈ)
theorem nhdsSet_Ico (h : a < b) : 𝓝ˢ (Ico a b) = 𝓝 a ⊔ 𝓟 (Ioo a b) := by
rw [← Ioo_insert_left h, nhdsSet_insert, nhdsSet_Ioo]
| Mathlib/Topology/Order/NhdsSet.lean | 44 | 45 | theorem nhdsSet_Ioc (h : a < b) : 𝓝ˢ (Ioc a b) = 𝓝 b ⊔ 𝓟 (Ioo a b) := by |
rw [← Ioo_insert_right h, nhdsSet_insert, nhdsSet_Ioo]
|
import Mathlib.Algebra.BigOperators.GroupWithZero.Finset
import Mathlib.Data.Finite.Card
import Mathlib.GroupTheory.Finiteness
import Mathlib.GroupTheory.GroupAction.Quotient
#align_import group_theory.index from "leanprover-community/mathlib"@"dc6c365e751e34d100e80fe6e314c3c3e0fd2988"
namespace Subgroup
open Cardinal
variable {G : Type*} [Group G] (H K L : Subgroup G)
@[to_additive "The index of a subgroup as a natural number,
and returns 0 if the index is infinite."]
noncomputable def index : ℕ :=
Nat.card (G ⧸ H)
#align subgroup.index Subgroup.index
#align add_subgroup.index AddSubgroup.index
@[to_additive "The relative index of a subgroup as a natural number,
and returns 0 if the relative index is infinite."]
noncomputable def relindex : ℕ :=
(H.subgroupOf K).index
#align subgroup.relindex Subgroup.relindex
#align add_subgroup.relindex AddSubgroup.relindex
@[to_additive]
theorem index_comap_of_surjective {G' : Type*} [Group G'] {f : G' →* G}
(hf : Function.Surjective f) : (H.comap f).index = H.index := by
letI := QuotientGroup.leftRel H
letI := QuotientGroup.leftRel (H.comap f)
have key : ∀ x y : G', Setoid.r x y ↔ Setoid.r (f x) (f y) := by
simp only [QuotientGroup.leftRel_apply]
exact fun x y => iff_of_eq (congr_arg (· ∈ H) (by rw [f.map_mul, f.map_inv]))
refine Cardinal.toNat_congr (Equiv.ofBijective (Quotient.map' f fun x y => (key x y).mp) ⟨?_, ?_⟩)
· simp_rw [← Quotient.eq''] at key
refine Quotient.ind' fun x => ?_
refine Quotient.ind' fun y => ?_
exact (key x y).mpr
· refine Quotient.ind' fun x => ?_
obtain ⟨y, hy⟩ := hf x
exact ⟨y, (Quotient.map'_mk'' f _ y).trans (congr_arg Quotient.mk'' hy)⟩
#align subgroup.index_comap_of_surjective Subgroup.index_comap_of_surjective
#align add_subgroup.index_comap_of_surjective AddSubgroup.index_comap_of_surjective
@[to_additive]
theorem index_comap {G' : Type*} [Group G'] (f : G' →* G) :
(H.comap f).index = H.relindex f.range :=
Eq.trans (congr_arg index (by rfl))
((H.subgroupOf f.range).index_comap_of_surjective f.rangeRestrict_surjective)
#align subgroup.index_comap Subgroup.index_comap
#align add_subgroup.index_comap AddSubgroup.index_comap
@[to_additive]
theorem relindex_comap {G' : Type*} [Group G'] (f : G' →* G) (K : Subgroup G') :
relindex (comap f H) K = relindex H (map f K) := by
rw [relindex, subgroupOf, comap_comap, index_comap, ← f.map_range, K.subtype_range]
#align subgroup.relindex_comap Subgroup.relindex_comap
#align add_subgroup.relindex_comap AddSubgroup.relindex_comap
variable {H K L}
@[to_additive relindex_mul_index]
theorem relindex_mul_index (h : H ≤ K) : H.relindex K * K.index = H.index :=
((mul_comm _ _).trans (Cardinal.toNat_mul _ _).symm).trans
(congr_arg Cardinal.toNat (Equiv.cardinal_eq (quotientEquivProdOfLE h))).symm
#align subgroup.relindex_mul_index Subgroup.relindex_mul_index
#align add_subgroup.relindex_mul_index AddSubgroup.relindex_mul_index
@[to_additive]
theorem index_dvd_of_le (h : H ≤ K) : K.index ∣ H.index :=
dvd_of_mul_left_eq (H.relindex K) (relindex_mul_index h)
#align subgroup.index_dvd_of_le Subgroup.index_dvd_of_le
#align add_subgroup.index_dvd_of_le AddSubgroup.index_dvd_of_le
@[to_additive]
theorem relindex_dvd_index_of_le (h : H ≤ K) : H.relindex K ∣ H.index :=
dvd_of_mul_right_eq K.index (relindex_mul_index h)
#align subgroup.relindex_dvd_index_of_le Subgroup.relindex_dvd_index_of_le
#align add_subgroup.relindex_dvd_index_of_le AddSubgroup.relindex_dvd_index_of_le
@[to_additive]
theorem relindex_subgroupOf (hKL : K ≤ L) :
(H.subgroupOf L).relindex (K.subgroupOf L) = H.relindex K :=
((index_comap (H.subgroupOf L) (inclusion hKL)).trans (congr_arg _ (inclusion_range hKL))).symm
#align subgroup.relindex_subgroup_of Subgroup.relindex_subgroupOf
#align add_subgroup.relindex_add_subgroup_of AddSubgroup.relindex_addSubgroupOf
variable (H K L)
@[to_additive relindex_mul_relindex]
theorem relindex_mul_relindex (hHK : H ≤ K) (hKL : K ≤ L) :
H.relindex K * K.relindex L = H.relindex L := by
rw [← relindex_subgroupOf hKL]
exact relindex_mul_index fun x hx => hHK hx
#align subgroup.relindex_mul_relindex Subgroup.relindex_mul_relindex
#align add_subgroup.relindex_mul_relindex AddSubgroup.relindex_mul_relindex
@[to_additive]
theorem inf_relindex_right : (H ⊓ K).relindex K = H.relindex K := by
rw [relindex, relindex, inf_subgroupOf_right]
#align subgroup.inf_relindex_right Subgroup.inf_relindex_right
#align add_subgroup.inf_relindex_right AddSubgroup.inf_relindex_right
@[to_additive]
theorem inf_relindex_left : (H ⊓ K).relindex H = K.relindex H := by
rw [inf_comm, inf_relindex_right]
#align subgroup.inf_relindex_left Subgroup.inf_relindex_left
#align add_subgroup.inf_relindex_left AddSubgroup.inf_relindex_left
@[to_additive relindex_inf_mul_relindex]
theorem relindex_inf_mul_relindex : H.relindex (K ⊓ L) * K.relindex L = (H ⊓ K).relindex L := by
rw [← inf_relindex_right H (K ⊓ L), ← inf_relindex_right K L, ← inf_relindex_right (H ⊓ K) L,
inf_assoc, relindex_mul_relindex (H ⊓ (K ⊓ L)) (K ⊓ L) L inf_le_right inf_le_right]
#align subgroup.relindex_inf_mul_relindex Subgroup.relindex_inf_mul_relindex
#align add_subgroup.relindex_inf_mul_relindex AddSubgroup.relindex_inf_mul_relindex
@[to_additive (attr := simp)]
theorem relindex_sup_right [K.Normal] : K.relindex (H ⊔ K) = K.relindex H :=
Nat.card_congr (QuotientGroup.quotientInfEquivProdNormalQuotient H K).toEquiv.symm
#align subgroup.relindex_sup_right Subgroup.relindex_sup_right
#align add_subgroup.relindex_sup_right AddSubgroup.relindex_sup_right
@[to_additive (attr := simp)]
theorem relindex_sup_left [K.Normal] : K.relindex (K ⊔ H) = K.relindex H := by
rw [sup_comm, relindex_sup_right]
#align subgroup.relindex_sup_left Subgroup.relindex_sup_left
#align add_subgroup.relindex_sup_left AddSubgroup.relindex_sup_left
@[to_additive]
theorem relindex_dvd_index_of_normal [H.Normal] : H.relindex K ∣ H.index :=
relindex_sup_right K H ▸ relindex_dvd_index_of_le le_sup_right
#align subgroup.relindex_dvd_index_of_normal Subgroup.relindex_dvd_index_of_normal
#align add_subgroup.relindex_dvd_index_of_normal AddSubgroup.relindex_dvd_index_of_normal
variable {H K}
@[to_additive]
theorem relindex_dvd_of_le_left (hHK : H ≤ K) : K.relindex L ∣ H.relindex L :=
inf_of_le_left hHK ▸ dvd_of_mul_left_eq _ (relindex_inf_mul_relindex _ _ _)
#align subgroup.relindex_dvd_of_le_left Subgroup.relindex_dvd_of_le_left
#align add_subgroup.relindex_dvd_of_le_left AddSubgroup.relindex_dvd_of_le_left
@[to_additive "An additive subgroup has index two if and only if there exists `a` such that
for all `b`, exactly one of `b + a` and `b` belong to `H`."]
theorem index_eq_two_iff : H.index = 2 ↔ ∃ a, ∀ b, Xor' (b * a ∈ H) (b ∈ H) := by
simp only [index, Nat.card_eq_two_iff' ((1 : G) : G ⧸ H), ExistsUnique, inv_mem_iff,
QuotientGroup.exists_mk, QuotientGroup.forall_mk, Ne, QuotientGroup.eq, mul_one,
xor_iff_iff_not]
refine exists_congr fun a =>
⟨fun ha b => ⟨fun hba hb => ?_, fun hb => ?_⟩, fun ha => ⟨?_, fun b hb => ?_⟩⟩
· exact ha.1 ((mul_mem_cancel_left hb).1 hba)
· exact inv_inv b ▸ ha.2 _ (mt (inv_mem_iff (x := b)).1 hb)
· rw [← inv_mem_iff (x := a), ← ha, inv_mul_self]
exact one_mem _
· rwa [ha, inv_mem_iff (x := b)]
#align subgroup.index_eq_two_iff Subgroup.index_eq_two_iff
#align add_subgroup.index_eq_two_iff AddSubgroup.index_eq_two_iff
@[to_additive]
| Mathlib/GroupTheory/Index.lean | 197 | 203 | theorem mul_mem_iff_of_index_two (h : H.index = 2) {a b : G} : a * b ∈ H ↔ (a ∈ H ↔ b ∈ H) := by |
by_cases ha : a ∈ H; · simp only [ha, true_iff_iff, mul_mem_cancel_left ha]
by_cases hb : b ∈ H; · simp only [hb, iff_true_iff, mul_mem_cancel_right hb]
simp only [ha, hb, iff_self_iff, iff_true_iff]
rcases index_eq_two_iff.1 h with ⟨c, hc⟩
refine (hc _).or.resolve_left ?_
rwa [mul_assoc, mul_mem_cancel_right ((hc _).or.resolve_right hb)]
|
import Mathlib.Init.Align
import Mathlib.Topology.PartialHomeomorph
#align_import geometry.manifold.charted_space from "leanprover-community/mathlib"@"431589bce478b2229eba14b14a283250428217db"
noncomputable section
open TopologicalSpace Topology
universe u
variable {H : Type u} {H' : Type*} {M : Type*} {M' : Type*} {M'' : Type*}
scoped[Manifold] infixr:100 " ≫ₕ " => PartialHomeomorph.trans
scoped[Manifold] infixr:100 " ≫ " => PartialEquiv.trans
open Set PartialHomeomorph Manifold -- Porting note: Added `Manifold`
section Groupoid
structure StructureGroupoid (H : Type u) [TopologicalSpace H] where
members : Set (PartialHomeomorph H H)
trans' : ∀ e e' : PartialHomeomorph H H, e ∈ members → e' ∈ members → e ≫ₕ e' ∈ members
symm' : ∀ e : PartialHomeomorph H H, e ∈ members → e.symm ∈ members
id_mem' : PartialHomeomorph.refl H ∈ members
locality' : ∀ e : PartialHomeomorph H H,
(∀ x ∈ e.source, ∃ s, IsOpen s ∧ x ∈ s ∧ e.restr s ∈ members) → e ∈ members
mem_of_eqOnSource' : ∀ e e' : PartialHomeomorph H H, e ∈ members → e' ≈ e → e' ∈ members
#align structure_groupoid StructureGroupoid
variable [TopologicalSpace H]
instance : Membership (PartialHomeomorph H H) (StructureGroupoid H) :=
⟨fun (e : PartialHomeomorph H H) (G : StructureGroupoid H) ↦ e ∈ G.members⟩
instance (H : Type u) [TopologicalSpace H] :
SetLike (StructureGroupoid H) (PartialHomeomorph H H) where
coe s := s.members
coe_injective' N O h := by cases N; cases O; congr
instance : Inf (StructureGroupoid H) :=
⟨fun G G' => StructureGroupoid.mk
(members := G.members ∩ G'.members)
(trans' := fun e e' he he' =>
⟨G.trans' e e' he.left he'.left, G'.trans' e e' he.right he'.right⟩)
(symm' := fun e he => ⟨G.symm' e he.left, G'.symm' e he.right⟩)
(id_mem' := ⟨G.id_mem', G'.id_mem'⟩)
(locality' := by
intro e hx
apply (mem_inter_iff e G.members G'.members).mpr
refine And.intro (G.locality' e ?_) (G'.locality' e ?_)
all_goals
intro x hex
rcases hx x hex with ⟨s, hs⟩
use s
refine And.intro hs.left (And.intro hs.right.left ?_)
· exact hs.right.right.left
· exact hs.right.right.right)
(mem_of_eqOnSource' := fun e e' he hee' =>
⟨G.mem_of_eqOnSource' e e' he.left hee', G'.mem_of_eqOnSource' e e' he.right hee'⟩)⟩
instance : InfSet (StructureGroupoid H) :=
⟨fun S => StructureGroupoid.mk
(members := ⋂ s ∈ S, s.members)
(trans' := by
simp only [mem_iInter]
intro e e' he he' i hi
exact i.trans' e e' (he i hi) (he' i hi))
(symm' := by
simp only [mem_iInter]
intro e he i hi
exact i.symm' e (he i hi))
(id_mem' := by
simp only [mem_iInter]
intro i _
exact i.id_mem')
(locality' := by
simp only [mem_iInter]
intro e he i hi
refine i.locality' e ?_
intro x hex
rcases he x hex with ⟨s, hs⟩
exact ⟨s, ⟨hs.left, ⟨hs.right.left, hs.right.right i hi⟩⟩⟩)
(mem_of_eqOnSource' := by
simp only [mem_iInter]
intro e e' he he'e
exact fun i hi => i.mem_of_eqOnSource' e e' (he i hi) he'e)⟩
theorem StructureGroupoid.trans (G : StructureGroupoid H) {e e' : PartialHomeomorph H H}
(he : e ∈ G) (he' : e' ∈ G) : e ≫ₕ e' ∈ G :=
G.trans' e e' he he'
#align structure_groupoid.trans StructureGroupoid.trans
theorem StructureGroupoid.symm (G : StructureGroupoid H) {e : PartialHomeomorph H H} (he : e ∈ G) :
e.symm ∈ G :=
G.symm' e he
#align structure_groupoid.symm StructureGroupoid.symm
theorem StructureGroupoid.id_mem (G : StructureGroupoid H) : PartialHomeomorph.refl H ∈ G :=
G.id_mem'
#align structure_groupoid.id_mem StructureGroupoid.id_mem
theorem StructureGroupoid.locality (G : StructureGroupoid H) {e : PartialHomeomorph H H}
(h : ∀ x ∈ e.source, ∃ s, IsOpen s ∧ x ∈ s ∧ e.restr s ∈ G) : e ∈ G :=
G.locality' e h
#align structure_groupoid.locality StructureGroupoid.locality
theorem StructureGroupoid.mem_of_eqOnSource (G : StructureGroupoid H) {e e' : PartialHomeomorph H H}
(he : e ∈ G) (h : e' ≈ e) : e' ∈ G :=
G.mem_of_eqOnSource' e e' he h
#align structure_groupoid.eq_on_source StructureGroupoid.mem_of_eqOnSource
theorem StructureGroupoid.mem_iff_of_eqOnSource {G : StructureGroupoid H}
{e e' : PartialHomeomorph H H} (h : e ≈ e') : e ∈ G ↔ e' ∈ G :=
⟨fun he ↦ G.mem_of_eqOnSource he (Setoid.symm h), fun he' ↦ G.mem_of_eqOnSource he' h⟩
instance StructureGroupoid.partialOrder : PartialOrder (StructureGroupoid H) :=
PartialOrder.lift StructureGroupoid.members fun a b h ↦ by
cases a
cases b
dsimp at h
induction h
rfl
#align structure_groupoid.partial_order StructureGroupoid.partialOrder
theorem StructureGroupoid.le_iff {G₁ G₂ : StructureGroupoid H} : G₁ ≤ G₂ ↔ ∀ e, e ∈ G₁ → e ∈ G₂ :=
Iff.rfl
#align structure_groupoid.le_iff StructureGroupoid.le_iff
def idGroupoid (H : Type u) [TopologicalSpace H] : StructureGroupoid H where
members := {PartialHomeomorph.refl H} ∪ { e : PartialHomeomorph H H | e.source = ∅ }
trans' e e' he he' := by
cases' he with he he
· simpa only [mem_singleton_iff.1 he, refl_trans]
· have : (e ≫ₕ e').source ⊆ e.source := sep_subset _ _
rw [he] at this
have : e ≫ₕ e' ∈ { e : PartialHomeomorph H H | e.source = ∅ } := eq_bot_iff.2 this
exact (mem_union _ _ _).2 (Or.inr this)
symm' e he := by
cases' (mem_union _ _ _).1 he with E E
· simp [mem_singleton_iff.mp E]
· right
simpa only [e.toPartialEquiv.image_source_eq_target.symm, mfld_simps] using E
id_mem' := mem_union_left _ rfl
locality' e he := by
rcases e.source.eq_empty_or_nonempty with h | h
· right
exact h
· left
rcases h with ⟨x, hx⟩
rcases he x hx with ⟨s, open_s, xs, hs⟩
have x's : x ∈ (e.restr s).source := by
rw [restr_source, open_s.interior_eq]
exact ⟨hx, xs⟩
cases' hs with hs hs
· replace hs : PartialHomeomorph.restr e s = PartialHomeomorph.refl H := by
simpa only using hs
have : (e.restr s).source = univ := by
rw [hs]
simp
have : e.toPartialEquiv.source ∩ interior s = univ := this
have : univ ⊆ interior s := by
rw [← this]
exact inter_subset_right
have : s = univ := by rwa [open_s.interior_eq, univ_subset_iff] at this
simpa only [this, restr_univ] using hs
· exfalso
rw [mem_setOf_eq] at hs
rwa [hs] at x's
mem_of_eqOnSource' e e' he he'e := by
cases' he with he he
· left
have : e = e' := by
refine eq_of_eqOnSource_univ (Setoid.symm he'e) ?_ ?_ <;>
rw [Set.mem_singleton_iff.1 he] <;> rfl
rwa [← this]
· right
have he : e.toPartialEquiv.source = ∅ := he
rwa [Set.mem_setOf_eq, EqOnSource.source_eq he'e]
#align id_groupoid idGroupoid
instance instStructureGroupoidOrderBot : OrderBot (StructureGroupoid H) where
bot := idGroupoid H
bot_le := by
intro u f hf
have hf : f ∈ {PartialHomeomorph.refl H} ∪ { e : PartialHomeomorph H H | e.source = ∅ } := hf
simp only [singleton_union, mem_setOf_eq, mem_insert_iff] at hf
cases' hf with hf hf
· rw [hf]
apply u.id_mem
· apply u.locality
intro x hx
rw [hf, mem_empty_iff_false] at hx
exact hx.elim
instance : Inhabited (StructureGroupoid H) := ⟨idGroupoid H⟩
structure Pregroupoid (H : Type*) [TopologicalSpace H] where
property : (H → H) → Set H → Prop
comp : ∀ {f g u v}, property f u → property g v →
IsOpen u → IsOpen v → IsOpen (u ∩ f ⁻¹' v) → property (g ∘ f) (u ∩ f ⁻¹' v)
id_mem : property id univ
locality :
∀ {f u}, IsOpen u → (∀ x ∈ u, ∃ v, IsOpen v ∧ x ∈ v ∧ property f (u ∩ v)) → property f u
congr : ∀ {f g : H → H} {u}, IsOpen u → (∀ x ∈ u, g x = f x) → property f u → property g u
#align pregroupoid Pregroupoid
def Pregroupoid.groupoid (PG : Pregroupoid H) : StructureGroupoid H where
members := { e : PartialHomeomorph H H | PG.property e e.source ∧ PG.property e.symm e.target }
trans' e e' he he' := by
constructor
· apply PG.comp he.1 he'.1 e.open_source e'.open_source
apply e.continuousOn_toFun.isOpen_inter_preimage e.open_source e'.open_source
· apply PG.comp he'.2 he.2 e'.open_target e.open_target
apply e'.continuousOn_invFun.isOpen_inter_preimage e'.open_target e.open_target
symm' e he := ⟨he.2, he.1⟩
id_mem' := ⟨PG.id_mem, PG.id_mem⟩
locality' e he := by
constructor
· refine PG.locality e.open_source fun x xu ↦ ?_
rcases he x xu with ⟨s, s_open, xs, hs⟩
refine ⟨s, s_open, xs, ?_⟩
convert hs.1 using 1
dsimp [PartialHomeomorph.restr]
rw [s_open.interior_eq]
· refine PG.locality e.open_target fun x xu ↦ ?_
rcases he (e.symm x) (e.map_target xu) with ⟨s, s_open, xs, hs⟩
refine ⟨e.target ∩ e.symm ⁻¹' s, ?_, ⟨xu, xs⟩, ?_⟩
· exact ContinuousOn.isOpen_inter_preimage e.continuousOn_invFun e.open_target s_open
· rw [← inter_assoc, inter_self]
convert hs.2 using 1
dsimp [PartialHomeomorph.restr]
rw [s_open.interior_eq]
mem_of_eqOnSource' e e' he ee' := by
constructor
· apply PG.congr e'.open_source ee'.2
simp only [ee'.1, he.1]
· have A := EqOnSource.symm' ee'
apply PG.congr e'.symm.open_source A.2
-- Porting note: was
-- convert he.2
-- rw [A.1]
-- rfl
rw [A.1, symm_toPartialEquiv, PartialEquiv.symm_source]
exact he.2
#align pregroupoid.groupoid Pregroupoid.groupoid
theorem mem_groupoid_of_pregroupoid {PG : Pregroupoid H} {e : PartialHomeomorph H H} :
e ∈ PG.groupoid ↔ PG.property e e.source ∧ PG.property e.symm e.target :=
Iff.rfl
#align mem_groupoid_of_pregroupoid mem_groupoid_of_pregroupoid
theorem groupoid_of_pregroupoid_le (PG₁ PG₂ : Pregroupoid H)
(h : ∀ f s, PG₁.property f s → PG₂.property f s) : PG₁.groupoid ≤ PG₂.groupoid := by
refine StructureGroupoid.le_iff.2 fun e he ↦ ?_
rw [mem_groupoid_of_pregroupoid] at he ⊢
exact ⟨h _ _ he.1, h _ _ he.2⟩
#align groupoid_of_pregroupoid_le groupoid_of_pregroupoid_le
| Mathlib/Geometry/Manifold/ChartedSpace.lean | 426 | 429 | theorem mem_pregroupoid_of_eqOnSource (PG : Pregroupoid H) {e e' : PartialHomeomorph H H}
(he' : e ≈ e') (he : PG.property e e.source) : PG.property e' e'.source := by |
rw [← he'.1]
exact PG.congr e.open_source he'.eqOn.symm he
|
import Mathlib.Topology.Category.TopCat.EpiMono
import Mathlib.Topology.Category.TopCat.Limits.Basic
import Mathlib.CategoryTheory.Limits.Shapes.Products
import Mathlib.CategoryTheory.Limits.ConcreteCategory
import Mathlib.Data.Set.Subsingleton
import Mathlib.Tactic.CategoryTheory.Elementwise
#align_import topology.category.Top.limits.products from "leanprover-community/mathlib"@"178a32653e369dce2da68dc6b2694e385d484ef1"
-- Porting note: every ML3 decl has an uppercase letter
set_option linter.uppercaseLean3 false
open TopologicalSpace
open CategoryTheory
open CategoryTheory.Limits
universe v u w
noncomputable section
namespace TopCat
variable {J : Type v} [SmallCategory J]
abbrev piπ {ι : Type v} (α : ι → TopCat.{max v u}) (i : ι) : TopCat.of (∀ i, α i) ⟶ α i :=
⟨fun f => f i, continuous_apply i⟩
#align Top.pi_π TopCat.piπ
@[simps! pt π_app]
def piFan {ι : Type v} (α : ι → TopCat.{max v u}) : Fan α :=
Fan.mk (TopCat.of (∀ i, α i)) (piπ.{v,u} α)
#align Top.pi_fan TopCat.piFan
def piFanIsLimit {ι : Type v} (α : ι → TopCat.{max v u}) : IsLimit (piFan α) where
lift S :=
{ toFun := fun s i => S.π.app ⟨i⟩ s
continuous_toFun := continuous_pi (fun i => (S.π.app ⟨i⟩).2) }
uniq := by
intro S m h
apply ContinuousMap.ext; intro x
funext i
set_option tactic.skipAssignedInstances false in
dsimp
rw [ContinuousMap.coe_mk, ← h ⟨i⟩]
rfl
fac s j := rfl
#align Top.pi_fan_is_limit TopCat.piFanIsLimit
def piIsoPi {ι : Type v} (α : ι → TopCat.{max v u}) : ∏ᶜ α ≅ TopCat.of (∀ i, α i) :=
(limit.isLimit _).conePointUniqueUpToIso (piFanIsLimit.{v, u} α)
-- Specifying the universes in `piFanIsLimit` wasn't necessary when we had `TopCatMax`
#align Top.pi_iso_pi TopCat.piIsoPi
@[reassoc (attr := simp)]
theorem piIsoPi_inv_π {ι : Type v} (α : ι → TopCat.{max v u}) (i : ι) :
(piIsoPi α).inv ≫ Pi.π α i = piπ α i := by simp [piIsoPi]
#align Top.pi_iso_pi_inv_π TopCat.piIsoPi_inv_π
theorem piIsoPi_inv_π_apply {ι : Type v} (α : ι → TopCat.{max v u}) (i : ι) (x : ∀ i, α i) :
(Pi.π α i : _) ((piIsoPi α).inv x) = x i :=
ConcreteCategory.congr_hom (piIsoPi_inv_π α i) x
#align Top.pi_iso_pi_inv_π_apply TopCat.piIsoPi_inv_π_apply
-- Porting note: needing the type ascription on `∏ᶜ α : TopCat.{max v u}` is unfortunate.
theorem piIsoPi_hom_apply {ι : Type v} (α : ι → TopCat.{max v u}) (i : ι)
(x : (∏ᶜ α : TopCat.{max v u})) : (piIsoPi α).hom x i = (Pi.π α i : _) x := by
have := piIsoPi_inv_π α i
rw [Iso.inv_comp_eq] at this
exact ConcreteCategory.congr_hom this x
#align Top.pi_iso_pi_hom_apply TopCat.piIsoPi_hom_apply
-- Porting note: Lean doesn't automatically reduce TopCat.of X|>.α to X now
abbrev sigmaι {ι : Type v} (α : ι → TopCat.{max v u}) (i : ι) : α i ⟶ TopCat.of (Σi, α i) := by
refine ContinuousMap.mk ?_ ?_
· dsimp
apply Sigma.mk i
· dsimp; continuity
#align Top.sigma_ι TopCat.sigmaι
@[simps! pt ι_app]
def sigmaCofan {ι : Type v} (α : ι → TopCat.{max v u}) : Cofan α :=
Cofan.mk (TopCat.of (Σi, α i)) (sigmaι α)
#align Top.sigma_cofan TopCat.sigmaCofan
def sigmaCofanIsColimit {ι : Type v} (β : ι → TopCat.{max v u}) : IsColimit (sigmaCofan β) where
desc S :=
{ toFun := fun (s : of (Σ i, β i)) => S.ι.app ⟨s.1⟩ s.2
continuous_toFun := continuous_sigma fun i => (S.ι.app ⟨i⟩).continuous_toFun }
uniq := by
intro S m h
ext ⟨i, x⟩
simp only [hom_apply, ← h]
congr
fac s j := by
cases j
aesop_cat
#align Top.sigma_cofan_is_colimit TopCat.sigmaCofanIsColimit
def sigmaIsoSigma {ι : Type v} (α : ι → TopCat.{max v u}) : ∐ α ≅ TopCat.of (Σi, α i) :=
(colimit.isColimit _).coconePointUniqueUpToIso (sigmaCofanIsColimit.{v, u} α)
-- Specifying the universes in `sigmaCofanIsColimit` wasn't necessary when we had `TopCatMax`
#align Top.sigma_iso_sigma TopCat.sigmaIsoSigma
@[reassoc (attr := simp)]
theorem sigmaIsoSigma_hom_ι {ι : Type v} (α : ι → TopCat.{max v u}) (i : ι) :
Sigma.ι α i ≫ (sigmaIsoSigma α).hom = sigmaι α i := by simp [sigmaIsoSigma]
#align Top.sigma_iso_sigma_hom_ι TopCat.sigmaIsoSigma_hom_ι
theorem sigmaIsoSigma_hom_ι_apply {ι : Type v} (α : ι → TopCat.{max v u}) (i : ι) (x : α i) :
(sigmaIsoSigma α).hom ((Sigma.ι α i : _) x) = Sigma.mk i x :=
ConcreteCategory.congr_hom (sigmaIsoSigma_hom_ι α i) x
#align Top.sigma_iso_sigma_hom_ι_apply TopCat.sigmaIsoSigma_hom_ι_apply
| Mathlib/Topology/Category/TopCat/Limits/Products.lean | 136 | 139 | theorem sigmaIsoSigma_inv_apply {ι : Type v} (α : ι → TopCat.{max v u}) (i : ι) (x : α i) :
(sigmaIsoSigma α).inv ⟨i, x⟩ = (Sigma.ι α i : _) x := by |
rw [← sigmaIsoSigma_hom_ι_apply, ← comp_app, ← comp_app, Iso.hom_inv_id,
Category.comp_id]
|
import Mathlib.Combinatorics.Quiver.Basic
import Mathlib.Combinatorics.Quiver.Path
#align_import combinatorics.quiver.cast from "leanprover-community/mathlib"@"fc2ed6f838ce7c9b7c7171e58d78eaf7b438fb0e"
universe v v₁ v₂ u u₁ u₂
variable {U : Type*} [Quiver.{u + 1} U]
namespace Quiver
def Hom.cast {u v u' v' : U} (hu : u = u') (hv : v = v') (e : u ⟶ v) : u' ⟶ v' :=
Eq.ndrec (motive := (· ⟶ v')) (Eq.ndrec e hv) hu
#align quiver.hom.cast Quiver.Hom.cast
theorem Hom.cast_eq_cast {u v u' v' : U} (hu : u = u') (hv : v = v') (e : u ⟶ v) :
e.cast hu hv = _root_.cast (by {rw [hu, hv]}) e := by
subst_vars
rfl
#align quiver.hom.cast_eq_cast Quiver.Hom.cast_eq_cast
@[simp]
theorem Hom.cast_rfl_rfl {u v : U} (e : u ⟶ v) : e.cast rfl rfl = e :=
rfl
#align quiver.hom.cast_rfl_rfl Quiver.Hom.cast_rfl_rfl
@[simp]
| Mathlib/Combinatorics/Quiver/Cast.lean | 50 | 54 | theorem Hom.cast_cast {u v u' v' u'' v'' : U} (e : u ⟶ v) (hu : u = u') (hv : v = v')
(hu' : u' = u'') (hv' : v' = v'') :
(e.cast hu hv).cast hu' hv' = e.cast (hu.trans hu') (hv.trans hv') := by |
subst_vars
rfl
|
import Mathlib.Data.Int.Range
import Mathlib.Data.ZMod.Basic
import Mathlib.NumberTheory.MulChar.Basic
#align_import number_theory.legendre_symbol.zmod_char from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a"
namespace ZMod
section QuadCharModP
@[simps]
def χ₄ : MulChar (ZMod 4) ℤ where
toFun := (![0, 1, 0, -1] : ZMod 4 → ℤ)
map_one' := rfl
map_mul' := by decide
map_nonunit' := by decide
#align zmod.χ₄ ZMod.χ₄
theorem isQuadratic_χ₄ : χ₄.IsQuadratic := by
intro a
-- Porting note (#11043): was `decide!`
fin_cases a
all_goals decide
#align zmod.is_quadratic_χ₄ ZMod.isQuadratic_χ₄
theorem χ₄_nat_mod_four (n : ℕ) : χ₄ n = χ₄ (n % 4 : ℕ) := by rw [← ZMod.natCast_mod n 4]
#align zmod.χ₄_nat_mod_four ZMod.χ₄_nat_mod_four
theorem χ₄_int_mod_four (n : ℤ) : χ₄ n = χ₄ (n % 4 : ℤ) := by
rw [← ZMod.intCast_mod n 4]
norm_cast
#align zmod.χ₄_int_mod_four ZMod.χ₄_int_mod_four
theorem χ₄_int_eq_if_mod_four (n : ℤ) :
χ₄ n = if n % 2 = 0 then 0 else if n % 4 = 1 then 1 else -1 := by
have help : ∀ m : ℤ, 0 ≤ m → m < 4 → χ₄ m = if m % 2 = 0 then 0 else if m = 1 then 1 else -1 := by
decide
rw [← Int.emod_emod_of_dvd n (by decide : (2 : ℤ) ∣ 4), ← ZMod.intCast_mod n 4]
exact help (n % 4) (Int.emod_nonneg n (by norm_num)) (Int.emod_lt n (by norm_num))
#align zmod.χ₄_int_eq_if_mod_four ZMod.χ₄_int_eq_if_mod_four
theorem χ₄_nat_eq_if_mod_four (n : ℕ) :
χ₄ n = if n % 2 = 0 then 0 else if n % 4 = 1 then 1 else -1 :=
mod_cast χ₄_int_eq_if_mod_four n
#align zmod.χ₄_nat_eq_if_mod_four ZMod.χ₄_nat_eq_if_mod_four
theorem χ₄_eq_neg_one_pow {n : ℕ} (hn : n % 2 = 1) : χ₄ n = (-1) ^ (n / 2) := by
rw [χ₄_nat_eq_if_mod_four]
simp only [hn, Nat.one_ne_zero, if_false]
conv_rhs => -- Porting note: was `nth_rw`
arg 2; rw [← Nat.div_add_mod n 4]
enter [1, 1, 1]; rw [(by norm_num : 4 = 2 * 2)]
rw [mul_assoc, add_comm, Nat.add_mul_div_left _ _ (by norm_num : 0 < 2), pow_add, pow_mul,
neg_one_sq, one_pow, mul_one]
have help : ∀ m : ℕ, m < 4 → m % 2 = 1 → ite (m = 1) (1 : ℤ) (-1) = (-1) ^ (m / 2) := by decide
exact
help (n % 4) (Nat.mod_lt n (by norm_num))
((Nat.mod_mod_of_dvd n (by decide : 2 ∣ 4)).trans hn)
#align zmod.χ₄_eq_neg_one_pow ZMod.χ₄_eq_neg_one_pow
theorem χ₄_nat_one_mod_four {n : ℕ} (hn : n % 4 = 1) : χ₄ n = 1 := by
rw [χ₄_nat_mod_four, hn]
rfl
#align zmod.χ₄_nat_one_mod_four ZMod.χ₄_nat_one_mod_four
theorem χ₄_nat_three_mod_four {n : ℕ} (hn : n % 4 = 3) : χ₄ n = -1 := by
rw [χ₄_nat_mod_four, hn]
rfl
#align zmod.χ₄_nat_three_mod_four ZMod.χ₄_nat_three_mod_four
theorem χ₄_int_one_mod_four {n : ℤ} (hn : n % 4 = 1) : χ₄ n = 1 := by
rw [χ₄_int_mod_four, hn]
rfl
#align zmod.χ₄_int_one_mod_four ZMod.χ₄_int_one_mod_four
theorem χ₄_int_three_mod_four {n : ℤ} (hn : n % 4 = 3) : χ₄ n = -1 := by
rw [χ₄_int_mod_four, hn]
rfl
#align zmod.χ₄_int_three_mod_four ZMod.χ₄_int_three_mod_four
theorem neg_one_pow_div_two_of_one_mod_four {n : ℕ} (hn : n % 4 = 1) : (-1 : ℤ) ^ (n / 2) = 1 := by
rw [← χ₄_eq_neg_one_pow (Nat.odd_of_mod_four_eq_one hn), ← natCast_mod, hn]
rfl
#align zmod.neg_one_pow_div_two_of_one_mod_four ZMod.neg_one_pow_div_two_of_one_mod_four
theorem neg_one_pow_div_two_of_three_mod_four {n : ℕ} (hn : n % 4 = 3) :
(-1 : ℤ) ^ (n / 2) = -1 := by
rw [← χ₄_eq_neg_one_pow (Nat.odd_of_mod_four_eq_three hn), ← natCast_mod, hn]
rfl
#align zmod.neg_one_pow_div_two_of_three_mod_four ZMod.neg_one_pow_div_two_of_three_mod_four
@[simps]
def χ₈ : MulChar (ZMod 8) ℤ where
toFun := (![0, 1, 0, -1, 0, -1, 0, 1] : ZMod 8 → ℤ)
map_one' := rfl
map_mul' := by decide
map_nonunit' := by decide
#align zmod.χ₈ ZMod.χ₈
theorem isQuadratic_χ₈ : χ₈.IsQuadratic := by
intro a
-- Porting note: was `decide!`
fin_cases a
all_goals decide
#align zmod.is_quadratic_χ₈ ZMod.isQuadratic_χ₈
| Mathlib/NumberTheory/LegendreSymbol/ZModChar.lean | 150 | 150 | theorem χ₈_nat_mod_eight (n : ℕ) : χ₈ n = χ₈ (n % 8 : ℕ) := by | rw [← ZMod.natCast_mod n 8]
|
import Mathlib.MeasureTheory.Constructions.Prod.Basic
import Mathlib.MeasureTheory.Integral.DominatedConvergence
import Mathlib.MeasureTheory.Integral.SetIntegral
#align_import measure_theory.constructions.prod.integral from "leanprover-community/mathlib"@"fd5edc43dc4f10b85abfe544b88f82cf13c5f844"
noncomputable section
open scoped Classical Topology ENNReal MeasureTheory
open Set Function Real ENNReal
open MeasureTheory MeasurableSpace MeasureTheory.Measure
open TopologicalSpace
open Filter hiding prod_eq map
variable {α α' β β' γ E : Type*}
variable [MeasurableSpace α] [MeasurableSpace α'] [MeasurableSpace β] [MeasurableSpace β']
variable [MeasurableSpace γ]
variable {μ μ' : Measure α} {ν ν' : Measure β} {τ : Measure γ}
variable [NormedAddCommGroup E]
theorem measurableSet_integrable [SigmaFinite ν] ⦃f : α → β → E⦄
(hf : StronglyMeasurable (uncurry f)) : MeasurableSet {x | Integrable (f x) ν} := by
simp_rw [Integrable, hf.of_uncurry_left.aestronglyMeasurable, true_and_iff]
exact measurableSet_lt (Measurable.lintegral_prod_right hf.ennnorm) measurable_const
#align measurable_set_integrable measurableSet_integrable
section
variable [NormedSpace ℝ E]
theorem MeasureTheory.StronglyMeasurable.integral_prod_right [SigmaFinite ν] ⦃f : α → β → E⦄
(hf : StronglyMeasurable (uncurry f)) : StronglyMeasurable fun x => ∫ y, f x y ∂ν := by
by_cases hE : CompleteSpace E; swap; · simp [integral, hE, stronglyMeasurable_const]
borelize E
haveI : SeparableSpace (range (uncurry f) ∪ {0} : Set E) :=
hf.separableSpace_range_union_singleton
let s : ℕ → SimpleFunc (α × β) E :=
SimpleFunc.approxOn _ hf.measurable (range (uncurry f) ∪ {0}) 0 (by simp)
let s' : ℕ → α → SimpleFunc β E := fun n x => (s n).comp (Prod.mk x) measurable_prod_mk_left
let f' : ℕ → α → E := fun n => {x | Integrable (f x) ν}.indicator fun x => (s' n x).integral ν
have hf' : ∀ n, StronglyMeasurable (f' n) := by
intro n; refine StronglyMeasurable.indicator ?_ (measurableSet_integrable hf)
have : ∀ x, ((s' n x).range.filter fun x => x ≠ 0) ⊆ (s n).range := by
intro x; refine Finset.Subset.trans (Finset.filter_subset _ _) ?_; intro y
simp_rw [SimpleFunc.mem_range]; rintro ⟨z, rfl⟩; exact ⟨(x, z), rfl⟩
simp only [SimpleFunc.integral_eq_sum_of_subset (this _)]
refine Finset.stronglyMeasurable_sum _ fun x _ => ?_
refine (Measurable.ennreal_toReal ?_).stronglyMeasurable.smul_const _
simp only [s', SimpleFunc.coe_comp, preimage_comp]
apply measurable_measure_prod_mk_left
exact (s n).measurableSet_fiber x
have h2f' : Tendsto f' atTop (𝓝 fun x : α => ∫ y : β, f x y ∂ν) := by
rw [tendsto_pi_nhds]; intro x
by_cases hfx : Integrable (f x) ν
· have (n) : Integrable (s' n x) ν := by
apply (hfx.norm.add hfx.norm).mono' (s' n x).aestronglyMeasurable
filter_upwards with y
simp_rw [s', SimpleFunc.coe_comp]; exact SimpleFunc.norm_approxOn_zero_le _ _ (x, y) n
simp only [f', hfx, SimpleFunc.integral_eq_integral _ (this _), indicator_of_mem,
mem_setOf_eq]
refine
tendsto_integral_of_dominated_convergence (fun y => ‖f x y‖ + ‖f x y‖)
(fun n => (s' n x).aestronglyMeasurable) (hfx.norm.add hfx.norm) ?_ ?_
· refine fun n => eventually_of_forall fun y =>
SimpleFunc.norm_approxOn_zero_le ?_ ?_ (x, y) n
-- Porting note: Lean 3 solved the following two subgoals on its own
· exact hf.measurable
· simp
· refine eventually_of_forall fun y => SimpleFunc.tendsto_approxOn ?_ ?_ ?_
-- Porting note: Lean 3 solved the following two subgoals on its own
· exact hf.measurable.of_uncurry_left
· simp
apply subset_closure
simp [-uncurry_apply_pair]
· simp [f', hfx, integral_undef]
exact stronglyMeasurable_of_tendsto _ hf' h2f'
#align measure_theory.strongly_measurable.integral_prod_right MeasureTheory.StronglyMeasurable.integral_prod_right
theorem MeasureTheory.StronglyMeasurable.integral_prod_right' [SigmaFinite ν] ⦃f : α × β → E⦄
(hf : StronglyMeasurable f) : StronglyMeasurable fun x => ∫ y, f (x, y) ∂ν := by
rw [← uncurry_curry f] at hf; exact hf.integral_prod_right
#align measure_theory.strongly_measurable.integral_prod_right' MeasureTheory.StronglyMeasurable.integral_prod_right'
theorem MeasureTheory.StronglyMeasurable.integral_prod_left [SigmaFinite μ] ⦃f : α → β → E⦄
(hf : StronglyMeasurable (uncurry f)) : StronglyMeasurable fun y => ∫ x, f x y ∂μ :=
(hf.comp_measurable measurable_swap).integral_prod_right'
#align measure_theory.strongly_measurable.integral_prod_left MeasureTheory.StronglyMeasurable.integral_prod_left
theorem MeasureTheory.StronglyMeasurable.integral_prod_left' [SigmaFinite μ] ⦃f : α × β → E⦄
(hf : StronglyMeasurable f) : StronglyMeasurable fun y => ∫ x, f (x, y) ∂μ :=
(hf.comp_measurable measurable_swap).integral_prod_right'
#align measure_theory.strongly_measurable.integral_prod_left' MeasureTheory.StronglyMeasurable.integral_prod_left'
end
open MeasureTheory.Measure
section
nonrec theorem MeasureTheory.AEStronglyMeasurable.prod_swap {γ : Type*} [TopologicalSpace γ]
[SigmaFinite μ] [SigmaFinite ν] {f : β × α → γ} (hf : AEStronglyMeasurable f (ν.prod μ)) :
AEStronglyMeasurable (fun z : α × β => f z.swap) (μ.prod ν) := by
rw [← prod_swap] at hf
exact hf.comp_measurable measurable_swap
#align measure_theory.ae_strongly_measurable.prod_swap MeasureTheory.AEStronglyMeasurable.prod_swap
theorem MeasureTheory.AEStronglyMeasurable.fst {γ} [TopologicalSpace γ] [SigmaFinite ν] {f : α → γ}
(hf : AEStronglyMeasurable f μ) : AEStronglyMeasurable (fun z : α × β => f z.1) (μ.prod ν) :=
hf.comp_quasiMeasurePreserving quasiMeasurePreserving_fst
#align measure_theory.ae_strongly_measurable.fst MeasureTheory.AEStronglyMeasurable.fst
theorem MeasureTheory.AEStronglyMeasurable.snd {γ} [TopologicalSpace γ] [SigmaFinite ν] {f : β → γ}
(hf : AEStronglyMeasurable f ν) : AEStronglyMeasurable (fun z : α × β => f z.2) (μ.prod ν) :=
hf.comp_quasiMeasurePreserving quasiMeasurePreserving_snd
#align measure_theory.ae_strongly_measurable.snd MeasureTheory.AEStronglyMeasurable.snd
theorem MeasureTheory.AEStronglyMeasurable.integral_prod_right' [SigmaFinite ν] [NormedSpace ℝ E]
⦃f : α × β → E⦄ (hf : AEStronglyMeasurable f (μ.prod ν)) :
AEStronglyMeasurable (fun x => ∫ y, f (x, y) ∂ν) μ :=
⟨fun x => ∫ y, hf.mk f (x, y) ∂ν, hf.stronglyMeasurable_mk.integral_prod_right', by
filter_upwards [ae_ae_of_ae_prod hf.ae_eq_mk] with _ hx using integral_congr_ae hx⟩
#align measure_theory.ae_strongly_measurable.integral_prod_right' MeasureTheory.AEStronglyMeasurable.integral_prod_right'
theorem MeasureTheory.AEStronglyMeasurable.prod_mk_left {γ : Type*} [SigmaFinite ν]
[TopologicalSpace γ] {f : α × β → γ} (hf : AEStronglyMeasurable f (μ.prod ν)) :
∀ᵐ x ∂μ, AEStronglyMeasurable (fun y => f (x, y)) ν := by
filter_upwards [ae_ae_of_ae_prod hf.ae_eq_mk] with x hx
exact
⟨fun y => hf.mk f (x, y), hf.stronglyMeasurable_mk.comp_measurable measurable_prod_mk_left, hx⟩
#align measure_theory.ae_strongly_measurable.prod_mk_left MeasureTheory.AEStronglyMeasurable.prod_mk_left
end
namespace MeasureTheory
variable [SigmaFinite ν]
section
theorem integrable_swap_iff [SigmaFinite μ] {f : α × β → E} :
Integrable (f ∘ Prod.swap) (ν.prod μ) ↔ Integrable f (μ.prod ν) :=
measurePreserving_swap.integrable_comp_emb MeasurableEquiv.prodComm.measurableEmbedding
#align measure_theory.integrable_swap_iff MeasureTheory.integrable_swap_iff
theorem Integrable.swap [SigmaFinite μ] ⦃f : α × β → E⦄ (hf : Integrable f (μ.prod ν)) :
Integrable (f ∘ Prod.swap) (ν.prod μ) :=
integrable_swap_iff.2 hf
#align measure_theory.integrable.swap MeasureTheory.Integrable.swap
theorem hasFiniteIntegral_prod_iff ⦃f : α × β → E⦄ (h1f : StronglyMeasurable f) :
HasFiniteIntegral f (μ.prod ν) ↔
(∀ᵐ x ∂μ, HasFiniteIntegral (fun y => f (x, y)) ν) ∧
HasFiniteIntegral (fun x => ∫ y, ‖f (x, y)‖ ∂ν) μ := by
simp only [HasFiniteIntegral, lintegral_prod_of_measurable _ h1f.ennnorm]
have (x) : ∀ᵐ y ∂ν, 0 ≤ ‖f (x, y)‖ := by filter_upwards with y using norm_nonneg _
simp_rw [integral_eq_lintegral_of_nonneg_ae (this _)
(h1f.norm.comp_measurable measurable_prod_mk_left).aestronglyMeasurable,
ennnorm_eq_ofReal toReal_nonneg, ofReal_norm_eq_coe_nnnorm]
-- this fact is probably too specialized to be its own lemma
have : ∀ {p q r : Prop} (_ : r → p), (r ↔ p ∧ q) ↔ p → (r ↔ q) := fun {p q r} h1 => by
rw [← and_congr_right_iff, and_iff_right_of_imp h1]
rw [this]
· intro h2f; rw [lintegral_congr_ae]
filter_upwards [h2f] with x hx
rw [ofReal_toReal]; rw [← lt_top_iff_ne_top]; exact hx
· intro h2f; refine ae_lt_top ?_ h2f.ne; exact h1f.ennnorm.lintegral_prod_right'
#align measure_theory.has_finite_integral_prod_iff MeasureTheory.hasFiniteIntegral_prod_iff
theorem hasFiniteIntegral_prod_iff' ⦃f : α × β → E⦄ (h1f : AEStronglyMeasurable f (μ.prod ν)) :
HasFiniteIntegral f (μ.prod ν) ↔
(∀ᵐ x ∂μ, HasFiniteIntegral (fun y => f (x, y)) ν) ∧
HasFiniteIntegral (fun x => ∫ y, ‖f (x, y)‖ ∂ν) μ := by
rw [hasFiniteIntegral_congr h1f.ae_eq_mk,
hasFiniteIntegral_prod_iff h1f.stronglyMeasurable_mk]
apply and_congr
· apply eventually_congr
filter_upwards [ae_ae_of_ae_prod h1f.ae_eq_mk.symm]
intro x hx
exact hasFiniteIntegral_congr hx
· apply hasFiniteIntegral_congr
filter_upwards [ae_ae_of_ae_prod h1f.ae_eq_mk.symm] with _ hx using
integral_congr_ae (EventuallyEq.fun_comp hx _)
#align measure_theory.has_finite_integral_prod_iff' MeasureTheory.hasFiniteIntegral_prod_iff'
theorem integrable_prod_iff ⦃f : α × β → E⦄ (h1f : AEStronglyMeasurable f (μ.prod ν)) :
Integrable f (μ.prod ν) ↔
(∀ᵐ x ∂μ, Integrable (fun y => f (x, y)) ν) ∧ Integrable (fun x => ∫ y, ‖f (x, y)‖ ∂ν) μ := by
simp [Integrable, h1f, hasFiniteIntegral_prod_iff', h1f.norm.integral_prod_right',
h1f.prod_mk_left]
#align measure_theory.integrable_prod_iff MeasureTheory.integrable_prod_iff
theorem integrable_prod_iff' [SigmaFinite μ] ⦃f : α × β → E⦄
(h1f : AEStronglyMeasurable f (μ.prod ν)) :
Integrable f (μ.prod ν) ↔
(∀ᵐ y ∂ν, Integrable (fun x => f (x, y)) μ) ∧ Integrable (fun y => ∫ x, ‖f (x, y)‖ ∂μ) ν := by
convert integrable_prod_iff h1f.prod_swap using 1
rw [funext fun _ => Function.comp_apply.symm, integrable_swap_iff]
#align measure_theory.integrable_prod_iff' MeasureTheory.integrable_prod_iff'
theorem Integrable.prod_left_ae [SigmaFinite μ] ⦃f : α × β → E⦄ (hf : Integrable f (μ.prod ν)) :
∀ᵐ y ∂ν, Integrable (fun x => f (x, y)) μ :=
((integrable_prod_iff' hf.aestronglyMeasurable).mp hf).1
#align measure_theory.integrable.prod_left_ae MeasureTheory.Integrable.prod_left_ae
theorem Integrable.prod_right_ae [SigmaFinite μ] ⦃f : α × β → E⦄ (hf : Integrable f (μ.prod ν)) :
∀ᵐ x ∂μ, Integrable (fun y => f (x, y)) ν :=
hf.swap.prod_left_ae
#align measure_theory.integrable.prod_right_ae MeasureTheory.Integrable.prod_right_ae
theorem Integrable.integral_norm_prod_left ⦃f : α × β → E⦄ (hf : Integrable f (μ.prod ν)) :
Integrable (fun x => ∫ y, ‖f (x, y)‖ ∂ν) μ :=
((integrable_prod_iff hf.aestronglyMeasurable).mp hf).2
#align measure_theory.integrable.integral_norm_prod_left MeasureTheory.Integrable.integral_norm_prod_left
theorem Integrable.integral_norm_prod_right [SigmaFinite μ] ⦃f : α × β → E⦄
(hf : Integrable f (μ.prod ν)) : Integrable (fun y => ∫ x, ‖f (x, y)‖ ∂μ) ν :=
hf.swap.integral_norm_prod_left
#align measure_theory.integrable.integral_norm_prod_right MeasureTheory.Integrable.integral_norm_prod_right
| Mathlib/MeasureTheory/Constructions/Prod/Integral.lean | 308 | 314 | theorem Integrable.prod_smul {𝕜 : Type*} [NontriviallyNormedField 𝕜] [NormedSpace 𝕜 E]
{f : α → 𝕜} {g : β → E} (hf : Integrable f μ) (hg : Integrable g ν) :
Integrable (fun z : α × β => f z.1 • g z.2) (μ.prod ν) := by |
refine (integrable_prod_iff ?_).2 ⟨?_, ?_⟩
· exact hf.1.fst.smul hg.1.snd
· exact eventually_of_forall fun x => hg.smul (f x)
· simpa only [norm_smul, integral_mul_left] using hf.norm.mul_const _
|
import Mathlib.Algebra.BigOperators.Intervals
import Mathlib.Analysis.Normed.Group.Basic
import Mathlib.Topology.Instances.NNReal
#align_import analysis.normed.group.infinite_sum from "leanprover-community/mathlib"@"9a59dcb7a2d06bf55da57b9030169219980660cd"
open Topology NNReal
open Finset Filter Metric
variable {ι α E F : Type*} [SeminormedAddCommGroup E] [SeminormedAddCommGroup F]
theorem cauchySeq_finset_iff_vanishing_norm {f : ι → E} :
(CauchySeq fun s : Finset ι => ∑ i ∈ s, f i) ↔
∀ ε > (0 : ℝ), ∃ s : Finset ι, ∀ t, Disjoint t s → ‖∑ i ∈ t, f i‖ < ε := by
rw [cauchySeq_finset_iff_sum_vanishing, nhds_basis_ball.forall_iff]
· simp only [ball_zero_eq, Set.mem_setOf_eq]
· rintro s t hst ⟨s', hs'⟩
exact ⟨s', fun t' ht' => hst <| hs' _ ht'⟩
#align cauchy_seq_finset_iff_vanishing_norm cauchySeq_finset_iff_vanishing_norm
theorem summable_iff_vanishing_norm [CompleteSpace E] {f : ι → E} :
Summable f ↔ ∀ ε > (0 : ℝ), ∃ s : Finset ι, ∀ t, Disjoint t s → ‖∑ i ∈ t, f i‖ < ε := by
rw [summable_iff_cauchySeq_finset, cauchySeq_finset_iff_vanishing_norm]
#align summable_iff_vanishing_norm summable_iff_vanishing_norm
| Mathlib/Analysis/Normed/Group/InfiniteSum.lean | 54 | 68 | theorem cauchySeq_finset_of_norm_bounded_eventually {f : ι → E} {g : ι → ℝ} (hg : Summable g)
(h : ∀ᶠ i in cofinite, ‖f i‖ ≤ g i) : CauchySeq fun s => ∑ i ∈ s, f i := by |
refine cauchySeq_finset_iff_vanishing_norm.2 fun ε hε => ?_
rcases summable_iff_vanishing_norm.1 hg ε hε with ⟨s, hs⟩
classical
refine ⟨s ∪ h.toFinset, fun t ht => ?_⟩
have : ∀ i ∈ t, ‖f i‖ ≤ g i := by
intro i hi
simp only [disjoint_left, mem_union, not_or, h.mem_toFinset, Set.mem_compl_iff,
Classical.not_not] at ht
exact (ht hi).2
calc
‖∑ i ∈ t, f i‖ ≤ ∑ i ∈ t, g i := norm_sum_le_of_le _ this
_ ≤ ‖∑ i ∈ t, g i‖ := le_abs_self _
_ < ε := hs _ (ht.mono_right le_sup_left)
|
import Mathlib.Data.Nat.Bits
import Mathlib.Order.Lattice
#align_import data.nat.size from "leanprover-community/mathlib"@"18a5306c091183ac90884daa9373fa3b178e8607"
namespace Nat
section
set_option linter.deprecated false
theorem shiftLeft_eq_mul_pow (m) : ∀ n, m <<< n = m * 2 ^ n := shiftLeft_eq _
#align nat.shiftl_eq_mul_pow Nat.shiftLeft_eq_mul_pow
theorem shiftLeft'_tt_eq_mul_pow (m) : ∀ n, shiftLeft' true m n + 1 = (m + 1) * 2 ^ n
| 0 => by simp [shiftLeft', pow_zero, Nat.one_mul]
| k + 1 => by
change bit1 (shiftLeft' true m k) + 1 = (m + 1) * (2 ^ k * 2)
rw [bit1_val]
change 2 * (shiftLeft' true m k + 1) = _
rw [shiftLeft'_tt_eq_mul_pow m k, mul_left_comm, mul_comm 2]
#align nat.shiftl'_tt_eq_mul_pow Nat.shiftLeft'_tt_eq_mul_pow
end
#align nat.one_shiftl Nat.one_shiftLeft
#align nat.zero_shiftl Nat.zero_shiftLeft
#align nat.shiftr_eq_div_pow Nat.shiftRight_eq_div_pow
theorem shiftLeft'_ne_zero_left (b) {m} (h : m ≠ 0) (n) : shiftLeft' b m n ≠ 0 := by
induction n <;> simp [bit_ne_zero, shiftLeft', *]
#align nat.shiftl'_ne_zero_left Nat.shiftLeft'_ne_zero_left
theorem shiftLeft'_tt_ne_zero (m) : ∀ {n}, (n ≠ 0) → shiftLeft' true m n ≠ 0
| 0, h => absurd rfl h
| succ _, _ => Nat.bit1_ne_zero _
#align nat.shiftl'_tt_ne_zero Nat.shiftLeft'_tt_ne_zero
@[simp]
theorem size_zero : size 0 = 0 := by simp [size]
#align nat.size_zero Nat.size_zero
@[simp]
theorem size_bit {b n} (h : bit b n ≠ 0) : size (bit b n) = succ (size n) := by
rw [size]
conv =>
lhs
rw [binaryRec]
simp [h]
rw [div2_bit]
#align nat.size_bit Nat.size_bit
section
set_option linter.deprecated false
@[simp]
theorem size_bit0 {n} (h : n ≠ 0) : size (bit0 n) = succ (size n) :=
@size_bit false n (Nat.bit0_ne_zero h)
#align nat.size_bit0 Nat.size_bit0
@[simp]
theorem size_bit1 (n) : size (bit1 n) = succ (size n) :=
@size_bit true n (Nat.bit1_ne_zero n)
#align nat.size_bit1 Nat.size_bit1
@[simp]
theorem size_one : size 1 = 1 :=
show size (bit1 0) = 1 by rw [size_bit1, size_zero]
#align nat.size_one Nat.size_one
end
@[simp]
theorem size_shiftLeft' {b m n} (h : shiftLeft' b m n ≠ 0) :
size (shiftLeft' b m n) = size m + n := by
induction' n with n IH <;> simp [shiftLeft'] at h ⊢
rw [size_bit h, Nat.add_succ]
by_cases s0 : shiftLeft' b m n = 0 <;> [skip; rw [IH s0]]
rw [s0] at h ⊢
cases b; · exact absurd rfl h
have : shiftLeft' true m n + 1 = 1 := congr_arg (· + 1) s0
rw [shiftLeft'_tt_eq_mul_pow] at this
obtain rfl := succ.inj (eq_one_of_dvd_one ⟨_, this.symm⟩)
simp only [zero_add, one_mul] at this
obtain rfl : n = 0 := not_ne_iff.1 fun hn ↦ ne_of_gt (Nat.one_lt_pow hn (by decide)) this
rfl
#align nat.size_shiftl' Nat.size_shiftLeft'
-- TODO: decide whether `Nat.shiftLeft_eq` (which rewrites the LHS into a power) should be a simp
-- lemma; it was not in mathlib3. Until then, tell the simpNF linter to ignore the issue.
@[simp, nolint simpNF]
theorem size_shiftLeft {m} (h : m ≠ 0) (n) : size (m <<< n) = size m + n := by
simp only [size_shiftLeft' (shiftLeft'_ne_zero_left _ h _), ← shiftLeft'_false]
#align nat.size_shiftl Nat.size_shiftLeft
theorem lt_size_self (n : ℕ) : n < 2 ^ size n := by
rw [← one_shiftLeft]
have : ∀ {n}, n = 0 → n < 1 <<< (size n) := by simp
apply binaryRec _ _ n
· apply this rfl
intro b n IH
by_cases h : bit b n = 0
· apply this h
rw [size_bit h, shiftLeft_succ, shiftLeft_eq, one_mul, ← bit0_val]
exact bit_lt_bit0 _ (by simpa [shiftLeft_eq, shiftRight_eq_div_pow] using IH)
#align nat.lt_size_self Nat.lt_size_self
theorem size_le {m n : ℕ} : size m ≤ n ↔ m < 2 ^ n :=
⟨fun h => lt_of_lt_of_le (lt_size_self _) (pow_le_pow_of_le_right (by decide) h), by
rw [← one_shiftLeft]; revert n
apply binaryRec _ _ m
· intro n
simp
· intro b m IH n h
by_cases e : bit b m = 0
· simp [e]
rw [size_bit e]
cases' n with n
· exact e.elim (Nat.eq_zero_of_le_zero (le_of_lt_succ h))
· apply succ_le_succ (IH _)
apply Nat.lt_of_mul_lt_mul_left (a := 2)
simp only [← bit0_val, shiftLeft_succ] at *
exact lt_of_le_of_lt (bit0_le_bit b rfl.le) h⟩
#align nat.size_le Nat.size_le
theorem lt_size {m n : ℕ} : m < size n ↔ 2 ^ m ≤ n := by
rw [← not_lt, Decidable.iff_not_comm, not_lt, size_le]
#align nat.lt_size Nat.lt_size
theorem size_pos {n : ℕ} : 0 < size n ↔ 0 < n := by rw [lt_size]; rfl
#align nat.size_pos Nat.size_pos
theorem size_eq_zero {n : ℕ} : size n = 0 ↔ n = 0 := by
simpa [Nat.pos_iff_ne_zero, not_iff_not] using size_pos
#align nat.size_eq_zero Nat.size_eq_zero
theorem size_pow {n : ℕ} : size (2 ^ n) = n + 1 :=
le_antisymm (size_le.2 <| Nat.pow_lt_pow_right (by decide) (lt_succ_self _))
(lt_size.2 <| le_rfl)
#align nat.size_pow Nat.size_pow
theorem size_le_size {m n : ℕ} (h : m ≤ n) : size m ≤ size n :=
size_le.2 <| lt_of_le_of_lt h (lt_size_self _)
#align nat.size_le_size Nat.size_le_size
| Mathlib/Data/Nat/Size.lean | 157 | 161 | theorem size_eq_bits_len (n : ℕ) : n.bits.length = n.size := by |
induction' n using Nat.binaryRec' with b n h ih; · simp
rw [size_bit, bits_append_bit _ _ h]
· simp [ih]
· simpa [bit_eq_zero_iff]
|
import Mathlib.LinearAlgebra.QuadraticForm.TensorProduct
import Mathlib.LinearAlgebra.QuadraticForm.IsometryEquiv
suppress_compilation
universe uR uM₁ uM₂ uM₃ uM₄
variable {R : Type uR} {M₁ : Type uM₁} {M₂ : Type uM₂} {M₃ : Type uM₃} {M₄ : Type uM₄}
open scoped TensorProduct
namespace QuadraticForm
variable [CommRing R]
variable [AddCommGroup M₁] [AddCommGroup M₂] [AddCommGroup M₃] [AddCommGroup M₄]
variable [Module R M₁] [Module R M₂] [Module R M₃] [Module R M₄] [Invertible (2 : R)]
@[simp]
theorem tmul_comp_tensorMap
{Q₁ : QuadraticForm R M₁} {Q₂ : QuadraticForm R M₂}
{Q₃ : QuadraticForm R M₃} {Q₄ : QuadraticForm R M₄}
(f : Q₁ →qᵢ Q₂) (g : Q₃ →qᵢ Q₄) :
(Q₂.tmul Q₄).comp (TensorProduct.map f.toLinearMap g.toLinearMap) = Q₁.tmul Q₃ := by
have h₁ : Q₁ = Q₂.comp f.toLinearMap := QuadraticForm.ext fun x => (f.map_app x).symm
have h₃ : Q₃ = Q₄.comp g.toLinearMap := QuadraticForm.ext fun x => (g.map_app x).symm
refine (QuadraticForm.associated_rightInverse R).injective ?_
ext m₁ m₃ m₁' m₃'
simp [-associated_apply, h₁, h₃, associated_tmul]
@[simp]
theorem tmul_tensorMap_apply
{Q₁ : QuadraticForm R M₁} {Q₂ : QuadraticForm R M₂}
{Q₃ : QuadraticForm R M₃} {Q₄ : QuadraticForm R M₄}
(f : Q₁ →qᵢ Q₂) (g : Q₃ →qᵢ Q₄) (x : M₁ ⊗[R] M₃) :
Q₂.tmul Q₄ (TensorProduct.map f.toLinearMap g.toLinearMap x) = Q₁.tmul Q₃ x :=
DFunLike.congr_fun (tmul_comp_tensorMap f g) x
section tensorRId
| Mathlib/LinearAlgebra/QuadraticForm/TensorProduct/Isometries.lean | 153 | 159 | theorem comp_tensorRId_eq (Q₁ : QuadraticForm R M₁) :
Q₁.comp (TensorProduct.rid R M₁) = Q₁.tmul (sq (R := R)) := by |
refine (QuadraticForm.associated_rightInverse R).injective ?_
ext m₁ m₁'
dsimp [-associated_apply]
simp only [associated_tmul, QuadraticForm.associated_comp]
simp [-associated_apply, one_mul]
|
import Mathlib.Topology.Bornology.Basic
#align_import topology.bornology.constructions from "leanprover-community/mathlib"@"e3d9ab8faa9dea8f78155c6c27d62a621f4c152d"
open Set Filter Bornology Function
open Filter
variable {α β ι : Type*} {π : ι → Type*} [Bornology α] [Bornology β]
[∀ i, Bornology (π i)]
instance Prod.instBornology : Bornology (α × β) where
cobounded' := (cobounded α).coprod (cobounded β)
le_cofinite' :=
@coprod_cofinite α β ▸ coprod_mono ‹Bornology α›.le_cofinite ‹Bornology β›.le_cofinite
#align prod.bornology Prod.instBornology
instance Pi.instBornology : Bornology (∀ i, π i) where
cobounded' := Filter.coprodᵢ fun i => cobounded (π i)
le_cofinite' := iSup_le fun _ ↦ (comap_mono (Bornology.le_cofinite _)).trans (comap_cofinite_le _)
#align pi.bornology Pi.instBornology
abbrev Bornology.induced {α β : Type*} [Bornology β] (f : α → β) : Bornology α where
cobounded' := comap f (cobounded β)
le_cofinite' := (comap_mono (Bornology.le_cofinite β)).trans (comap_cofinite_le _)
#align bornology.induced Bornology.induced
instance {p : α → Prop} : Bornology (Subtype p) :=
Bornology.induced (Subtype.val : Subtype p → α)
namespace Bornology
theorem cobounded_prod : cobounded (α × β) = (cobounded α).coprod (cobounded β) :=
rfl
#align bornology.cobounded_prod Bornology.cobounded_prod
theorem isBounded_image_fst_and_snd {s : Set (α × β)} :
IsBounded (Prod.fst '' s) ∧ IsBounded (Prod.snd '' s) ↔ IsBounded s :=
compl_mem_coprod.symm
#align bornology.is_bounded_image_fst_and_snd Bornology.isBounded_image_fst_and_snd
lemma IsBounded.image_fst {s : Set (α × β)} (hs : IsBounded s) : IsBounded (Prod.fst '' s) :=
(isBounded_image_fst_and_snd.2 hs).1
lemma IsBounded.image_snd {s : Set (α × β)} (hs : IsBounded s) : IsBounded (Prod.snd '' s) :=
(isBounded_image_fst_and_snd.2 hs).2
variable {s : Set α} {t : Set β} {S : ∀ i, Set (π i)}
theorem IsBounded.fst_of_prod (h : IsBounded (s ×ˢ t)) (ht : t.Nonempty) : IsBounded s :=
fst_image_prod s ht ▸ h.image_fst
#align bornology.is_bounded.fst_of_prod Bornology.IsBounded.fst_of_prod
theorem IsBounded.snd_of_prod (h : IsBounded (s ×ˢ t)) (hs : s.Nonempty) : IsBounded t :=
snd_image_prod hs t ▸ h.image_snd
#align bornology.is_bounded.snd_of_prod Bornology.IsBounded.snd_of_prod
theorem IsBounded.prod (hs : IsBounded s) (ht : IsBounded t) : IsBounded (s ×ˢ t) :=
isBounded_image_fst_and_snd.1
⟨hs.subset <| fst_image_prod_subset _ _, ht.subset <| snd_image_prod_subset _ _⟩
#align bornology.is_bounded.prod Bornology.IsBounded.prod
theorem isBounded_prod_of_nonempty (hne : Set.Nonempty (s ×ˢ t)) :
IsBounded (s ×ˢ t) ↔ IsBounded s ∧ IsBounded t :=
⟨fun h => ⟨h.fst_of_prod hne.snd, h.snd_of_prod hne.fst⟩, fun h => h.1.prod h.2⟩
#align bornology.is_bounded_prod_of_nonempty Bornology.isBounded_prod_of_nonempty
theorem isBounded_prod : IsBounded (s ×ˢ t) ↔ s = ∅ ∨ t = ∅ ∨ IsBounded s ∧ IsBounded t := by
rcases s.eq_empty_or_nonempty with (rfl | hs); · simp
rcases t.eq_empty_or_nonempty with (rfl | ht); · simp
simp only [hs.ne_empty, ht.ne_empty, isBounded_prod_of_nonempty (hs.prod ht), false_or_iff]
#align bornology.is_bounded_prod Bornology.isBounded_prod
| Mathlib/Topology/Bornology/Constructions.lean | 94 | 96 | theorem isBounded_prod_self : IsBounded (s ×ˢ s) ↔ IsBounded s := by |
rcases s.eq_empty_or_nonempty with (rfl | hs); · simp
exact (isBounded_prod_of_nonempty (hs.prod hs)).trans and_self_iff
|
import Mathlib.Data.Matrix.Basic
variable {l m n o : Type*}
universe u v w
variable {R : Type*} {α : Type v} {β : Type w}
namespace Matrix
def col (w : m → α) : Matrix m Unit α :=
of fun x _ => w x
#align matrix.col Matrix.col
-- TODO: set as an equation lemma for `col`, see mathlib4#3024
@[simp]
theorem col_apply (w : m → α) (i j) : col w i j = w i :=
rfl
#align matrix.col_apply Matrix.col_apply
def row (v : n → α) : Matrix Unit n α :=
of fun _ y => v y
#align matrix.row Matrix.row
-- TODO: set as an equation lemma for `row`, see mathlib4#3024
@[simp]
theorem row_apply (v : n → α) (i j) : row v i j = v j :=
rfl
#align matrix.row_apply Matrix.row_apply
theorem col_injective : Function.Injective (col : (m → α) → _) :=
fun _x _y h => funext fun i => congr_fun₂ h i ()
@[simp] theorem col_inj {v w : m → α} : col v = col w ↔ v = w := col_injective.eq_iff
@[simp] theorem col_zero [Zero α] : col (0 : m → α) = 0 := rfl
@[simp] theorem col_eq_zero [Zero α] (v : m → α) : col v = 0 ↔ v = 0 := col_inj
@[simp]
theorem col_add [Add α] (v w : m → α) : col (v + w) = col v + col w := by
ext
rfl
#align matrix.col_add Matrix.col_add
@[simp]
theorem col_smul [SMul R α] (x : R) (v : m → α) : col (x • v) = x • col v := by
ext
rfl
#align matrix.col_smul Matrix.col_smul
theorem row_injective : Function.Injective (row : (n → α) → _) :=
fun _x _y h => funext fun j => congr_fun₂ h () j
@[simp] theorem row_inj {v w : n → α} : row v = row w ↔ v = w := row_injective.eq_iff
@[simp] theorem row_zero [Zero α] : row (0 : n → α) = 0 := rfl
@[simp] theorem row_eq_zero [Zero α] (v : n → α) : row v = 0 ↔ v = 0 := row_inj
@[simp]
theorem row_add [Add α] (v w : m → α) : row (v + w) = row v + row w := by
ext
rfl
#align matrix.row_add Matrix.row_add
@[simp]
theorem row_smul [SMul R α] (x : R) (v : m → α) : row (x • v) = x • row v := by
ext
rfl
#align matrix.row_smul Matrix.row_smul
@[simp]
theorem transpose_col (v : m → α) : (Matrix.col v)ᵀ = Matrix.row v := by
ext
rfl
#align matrix.transpose_col Matrix.transpose_col
@[simp]
theorem transpose_row (v : m → α) : (Matrix.row v)ᵀ = Matrix.col v := by
ext
rfl
#align matrix.transpose_row Matrix.transpose_row
@[simp]
theorem conjTranspose_col [Star α] (v : m → α) : (col v)ᴴ = row (star v) := by
ext
rfl
#align matrix.conj_transpose_col Matrix.conjTranspose_col
@[simp]
theorem conjTranspose_row [Star α] (v : m → α) : (row v)ᴴ = col (star v) := by
ext
rfl
#align matrix.conj_transpose_row Matrix.conjTranspose_row
theorem row_vecMul [Fintype m] [NonUnitalNonAssocSemiring α] (M : Matrix m n α) (v : m → α) :
Matrix.row (v ᵥ* M) = Matrix.row v * M := by
ext
rfl
#align matrix.row_vec_mul Matrix.row_vecMul
theorem col_vecMul [Fintype m] [NonUnitalNonAssocSemiring α] (M : Matrix m n α) (v : m → α) :
Matrix.col (v ᵥ* M) = (Matrix.row v * M)ᵀ := by
ext
rfl
#align matrix.col_vec_mul Matrix.col_vecMul
theorem col_mulVec [Fintype n] [NonUnitalNonAssocSemiring α] (M : Matrix m n α) (v : n → α) :
Matrix.col (M *ᵥ v) = M * Matrix.col v := by
ext
rfl
#align matrix.col_mul_vec Matrix.col_mulVec
theorem row_mulVec [Fintype n] [NonUnitalNonAssocSemiring α] (M : Matrix m n α) (v : n → α) :
Matrix.row (M *ᵥ v) = (M * Matrix.col v)ᵀ := by
ext
rfl
#align matrix.row_mul_vec Matrix.row_mulVec
@[simp]
theorem row_mul_col_apply [Fintype m] [Mul α] [AddCommMonoid α] (v w : m → α) (i j) :
(row v * col w) i j = v ⬝ᵥ w :=
rfl
#align matrix.row_mul_col_apply Matrix.row_mul_col_apply
@[simp]
theorem diag_col_mul_row [Mul α] [AddCommMonoid α] (a b : n → α) :
diag (col a * row b) = a * b := by
ext
simp [Matrix.mul_apply, col, row]
#align matrix.diag_col_mul_row Matrix.diag_col_mul_row
| Mathlib/Data/Matrix/RowCol.lean | 154 | 158 | theorem vecMulVec_eq [Mul α] [AddCommMonoid α] (w : m → α) (v : n → α) :
vecMulVec w v = col w * row v := by |
ext
simp only [vecMulVec, mul_apply, Fintype.univ_punit, Finset.sum_singleton]
rfl
|
import Mathlib.Topology.Constructions
import Mathlib.Topology.ContinuousOn
#align_import topology.bases from "leanprover-community/mathlib"@"bcfa726826abd57587355b4b5b7e78ad6527b7e4"
open Set Filter Function Topology
noncomputable section
namespace TopologicalSpace
universe u
variable {α : Type u} {β : Type*} [t : TopologicalSpace α] {B : Set (Set α)} {s : Set α}
structure IsTopologicalBasis (s : Set (Set α)) : Prop where
exists_subset_inter : ∀ t₁ ∈ s, ∀ t₂ ∈ s, ∀ x ∈ t₁ ∩ t₂, ∃ t₃ ∈ s, x ∈ t₃ ∧ t₃ ⊆ t₁ ∩ t₂
sUnion_eq : ⋃₀ s = univ
eq_generateFrom : t = generateFrom s
#align topological_space.is_topological_basis TopologicalSpace.IsTopologicalBasis
theorem IsTopologicalBasis.insert_empty {s : Set (Set α)} (h : IsTopologicalBasis s) :
IsTopologicalBasis (insert ∅ s) := by
refine ⟨?_, by rw [sUnion_insert, empty_union, h.sUnion_eq], ?_⟩
· rintro t₁ (rfl | h₁) t₂ (rfl | h₂) x ⟨hx₁, hx₂⟩
· cases hx₁
· cases hx₁
· cases hx₂
· obtain ⟨t₃, h₃, hs⟩ := h.exists_subset_inter _ h₁ _ h₂ x ⟨hx₁, hx₂⟩
exact ⟨t₃, .inr h₃, hs⟩
· rw [h.eq_generateFrom]
refine le_antisymm (le_generateFrom fun t => ?_) (generateFrom_anti <| subset_insert ∅ s)
rintro (rfl | ht)
· exact @isOpen_empty _ (generateFrom s)
· exact .basic t ht
#align topological_space.is_topological_basis.insert_empty TopologicalSpace.IsTopologicalBasis.insert_empty
theorem IsTopologicalBasis.diff_empty {s : Set (Set α)} (h : IsTopologicalBasis s) :
IsTopologicalBasis (s \ {∅}) := by
refine ⟨?_, by rw [sUnion_diff_singleton_empty, h.sUnion_eq], ?_⟩
· rintro t₁ ⟨h₁, -⟩ t₂ ⟨h₂, -⟩ x hx
obtain ⟨t₃, h₃, hs⟩ := h.exists_subset_inter _ h₁ _ h₂ x hx
exact ⟨t₃, ⟨h₃, Nonempty.ne_empty ⟨x, hs.1⟩⟩, hs⟩
· rw [h.eq_generateFrom]
refine le_antisymm (generateFrom_anti diff_subset) (le_generateFrom fun t ht => ?_)
obtain rfl | he := eq_or_ne t ∅
· exact @isOpen_empty _ (generateFrom _)
· exact .basic t ⟨ht, he⟩
#align topological_space.is_topological_basis.diff_empty TopologicalSpace.IsTopologicalBasis.diff_empty
theorem isTopologicalBasis_of_subbasis {s : Set (Set α)} (hs : t = generateFrom s) :
IsTopologicalBasis ((fun f => ⋂₀ f) '' { f : Set (Set α) | f.Finite ∧ f ⊆ s }) := by
subst t; letI := generateFrom s
refine ⟨?_, ?_, le_antisymm (le_generateFrom ?_) <| generateFrom_anti fun t ht => ?_⟩
· rintro _ ⟨t₁, ⟨hft₁, ht₁b⟩, rfl⟩ _ ⟨t₂, ⟨hft₂, ht₂b⟩, rfl⟩ x h
exact ⟨_, ⟨_, ⟨hft₁.union hft₂, union_subset ht₁b ht₂b⟩, sInter_union t₁ t₂⟩, h, Subset.rfl⟩
· rw [sUnion_image, iUnion₂_eq_univ_iff]
exact fun x => ⟨∅, ⟨finite_empty, empty_subset _⟩, sInter_empty.substr <| mem_univ x⟩
· rintro _ ⟨t, ⟨hft, htb⟩, rfl⟩
exact hft.isOpen_sInter fun s hs ↦ GenerateOpen.basic _ <| htb hs
· rw [← sInter_singleton t]
exact ⟨{t}, ⟨finite_singleton t, singleton_subset_iff.2 ht⟩, rfl⟩
#align topological_space.is_topological_basis_of_subbasis TopologicalSpace.isTopologicalBasis_of_subbasis
theorem IsTopologicalBasis.of_hasBasis_nhds {s : Set (Set α)}
(h_nhds : ∀ a, (𝓝 a).HasBasis (fun t ↦ t ∈ s ∧ a ∈ t) id) : IsTopologicalBasis s where
exists_subset_inter t₁ ht₁ t₂ ht₂ x hx := by
simpa only [and_assoc, (h_nhds x).mem_iff]
using (inter_mem ((h_nhds _).mem_of_mem ⟨ht₁, hx.1⟩) ((h_nhds _).mem_of_mem ⟨ht₂, hx.2⟩))
sUnion_eq := sUnion_eq_univ_iff.2 fun x ↦ (h_nhds x).ex_mem
eq_generateFrom := ext_nhds fun x ↦ by
simpa only [nhds_generateFrom, and_comm] using (h_nhds x).eq_biInf
theorem isTopologicalBasis_of_isOpen_of_nhds {s : Set (Set α)} (h_open : ∀ u ∈ s, IsOpen u)
(h_nhds : ∀ (a : α) (u : Set α), a ∈ u → IsOpen u → ∃ v ∈ s, a ∈ v ∧ v ⊆ u) :
IsTopologicalBasis s :=
.of_hasBasis_nhds <| fun a ↦
(nhds_basis_opens a).to_hasBasis' (by simpa [and_assoc] using h_nhds a)
fun t ⟨hts, hat⟩ ↦ (h_open _ hts).mem_nhds hat
#align topological_space.is_topological_basis_of_open_of_nhds TopologicalSpace.isTopologicalBasis_of_isOpen_of_nhds
theorem IsTopologicalBasis.mem_nhds_iff {a : α} {s : Set α} {b : Set (Set α)}
(hb : IsTopologicalBasis b) : s ∈ 𝓝 a ↔ ∃ t ∈ b, a ∈ t ∧ t ⊆ s := by
change s ∈ (𝓝 a).sets ↔ ∃ t ∈ b, a ∈ t ∧ t ⊆ s
rw [hb.eq_generateFrom, nhds_generateFrom, biInf_sets_eq]
· simp [and_assoc, and_left_comm]
· rintro s ⟨hs₁, hs₂⟩ t ⟨ht₁, ht₂⟩
let ⟨u, hu₁, hu₂, hu₃⟩ := hb.1 _ hs₂ _ ht₂ _ ⟨hs₁, ht₁⟩
exact ⟨u, ⟨hu₂, hu₁⟩, le_principal_iff.2 (hu₃.trans inter_subset_left),
le_principal_iff.2 (hu₃.trans inter_subset_right)⟩
· rcases eq_univ_iff_forall.1 hb.sUnion_eq a with ⟨i, h1, h2⟩
exact ⟨i, h2, h1⟩
#align topological_space.is_topological_basis.mem_nhds_iff TopologicalSpace.IsTopologicalBasis.mem_nhds_iff
theorem IsTopologicalBasis.isOpen_iff {s : Set α} {b : Set (Set α)} (hb : IsTopologicalBasis b) :
IsOpen s ↔ ∀ a ∈ s, ∃ t ∈ b, a ∈ t ∧ t ⊆ s := by simp [isOpen_iff_mem_nhds, hb.mem_nhds_iff]
#align topological_space.is_topological_basis.is_open_iff TopologicalSpace.IsTopologicalBasis.isOpen_iff
theorem IsTopologicalBasis.nhds_hasBasis {b : Set (Set α)} (hb : IsTopologicalBasis b) {a : α} :
(𝓝 a).HasBasis (fun t : Set α => t ∈ b ∧ a ∈ t) fun t => t :=
⟨fun s => hb.mem_nhds_iff.trans <| by simp only [and_assoc]⟩
#align topological_space.is_topological_basis.nhds_has_basis TopologicalSpace.IsTopologicalBasis.nhds_hasBasis
protected theorem IsTopologicalBasis.isOpen {s : Set α} {b : Set (Set α)}
(hb : IsTopologicalBasis b) (hs : s ∈ b) : IsOpen s := by
rw [hb.eq_generateFrom]
exact .basic s hs
#align topological_space.is_topological_basis.is_open TopologicalSpace.IsTopologicalBasis.isOpen
protected theorem IsTopologicalBasis.mem_nhds {a : α} {s : Set α} {b : Set (Set α)}
(hb : IsTopologicalBasis b) (hs : s ∈ b) (ha : a ∈ s) : s ∈ 𝓝 a :=
(hb.isOpen hs).mem_nhds ha
#align topological_space.is_topological_basis.mem_nhds TopologicalSpace.IsTopologicalBasis.mem_nhds
theorem IsTopologicalBasis.exists_subset_of_mem_open {b : Set (Set α)} (hb : IsTopologicalBasis b)
{a : α} {u : Set α} (au : a ∈ u) (ou : IsOpen u) : ∃ v ∈ b, a ∈ v ∧ v ⊆ u :=
hb.mem_nhds_iff.1 <| IsOpen.mem_nhds ou au
#align topological_space.is_topological_basis.exists_subset_of_mem_open TopologicalSpace.IsTopologicalBasis.exists_subset_of_mem_open
theorem IsTopologicalBasis.open_eq_sUnion' {B : Set (Set α)} (hB : IsTopologicalBasis B) {u : Set α}
(ou : IsOpen u) : u = ⋃₀ { s ∈ B | s ⊆ u } :=
ext fun _a =>
⟨fun ha =>
let ⟨b, hb, ab, bu⟩ := hB.exists_subset_of_mem_open ha ou
⟨b, ⟨hb, bu⟩, ab⟩,
fun ⟨_b, ⟨_, bu⟩, ab⟩ => bu ab⟩
#align topological_space.is_topological_basis.open_eq_sUnion' TopologicalSpace.IsTopologicalBasis.open_eq_sUnion'
theorem IsTopologicalBasis.open_eq_sUnion {B : Set (Set α)} (hB : IsTopologicalBasis B) {u : Set α}
(ou : IsOpen u) : ∃ S ⊆ B, u = ⋃₀ S :=
⟨{ s ∈ B | s ⊆ u }, fun _ h => h.1, hB.open_eq_sUnion' ou⟩
#align topological_space.is_topological_basis.open_eq_sUnion TopologicalSpace.IsTopologicalBasis.open_eq_sUnion
theorem IsTopologicalBasis.open_iff_eq_sUnion {B : Set (Set α)} (hB : IsTopologicalBasis B)
{u : Set α} : IsOpen u ↔ ∃ S ⊆ B, u = ⋃₀ S :=
⟨hB.open_eq_sUnion, fun ⟨_S, hSB, hu⟩ => hu.symm ▸ isOpen_sUnion fun _s hs => hB.isOpen (hSB hs)⟩
#align topological_space.is_topological_basis.open_iff_eq_sUnion TopologicalSpace.IsTopologicalBasis.open_iff_eq_sUnion
theorem IsTopologicalBasis.open_eq_iUnion {B : Set (Set α)} (hB : IsTopologicalBasis B) {u : Set α}
(ou : IsOpen u) : ∃ (β : Type u) (f : β → Set α), (u = ⋃ i, f i) ∧ ∀ i, f i ∈ B :=
⟨↥({ s ∈ B | s ⊆ u }), (↑), by
rw [← sUnion_eq_iUnion]
apply hB.open_eq_sUnion' ou, fun s => And.left s.2⟩
#align topological_space.is_topological_basis.open_eq_Union TopologicalSpace.IsTopologicalBasis.open_eq_iUnion
lemma IsTopologicalBasis.subset_of_forall_subset {t : Set α} (hB : IsTopologicalBasis B)
(hs : IsOpen s) (h : ∀ U ∈ B, U ⊆ s → U ⊆ t) : s ⊆ t := by
rw [hB.open_eq_sUnion' hs]; simpa [sUnion_subset_iff]
lemma IsTopologicalBasis.eq_of_forall_subset_iff {t : Set α} (hB : IsTopologicalBasis B)
(hs : IsOpen s) (ht : IsOpen t) (h : ∀ U ∈ B, U ⊆ s ↔ U ⊆ t) : s = t := by
rw [hB.open_eq_sUnion' hs, hB.open_eq_sUnion' ht]
exact congr_arg _ (Set.ext fun U ↦ and_congr_right <| h _)
theorem IsTopologicalBasis.mem_closure_iff {b : Set (Set α)} (hb : IsTopologicalBasis b) {s : Set α}
{a : α} : a ∈ closure s ↔ ∀ o ∈ b, a ∈ o → (o ∩ s).Nonempty :=
(mem_closure_iff_nhds_basis' hb.nhds_hasBasis).trans <| by simp only [and_imp]
#align topological_space.is_topological_basis.mem_closure_iff TopologicalSpace.IsTopologicalBasis.mem_closure_iff
theorem IsTopologicalBasis.dense_iff {b : Set (Set α)} (hb : IsTopologicalBasis b) {s : Set α} :
Dense s ↔ ∀ o ∈ b, Set.Nonempty o → (o ∩ s).Nonempty := by
simp only [Dense, hb.mem_closure_iff]
exact ⟨fun h o hb ⟨a, ha⟩ => h a o hb ha, fun h a o hb ha => h o hb ⟨a, ha⟩⟩
#align topological_space.is_topological_basis.dense_iff TopologicalSpace.IsTopologicalBasis.dense_iff
theorem IsTopologicalBasis.isOpenMap_iff {β} [TopologicalSpace β] {B : Set (Set α)}
(hB : IsTopologicalBasis B) {f : α → β} : IsOpenMap f ↔ ∀ s ∈ B, IsOpen (f '' s) := by
refine ⟨fun H o ho => H _ (hB.isOpen ho), fun hf o ho => ?_⟩
rw [hB.open_eq_sUnion' ho, sUnion_eq_iUnion, image_iUnion]
exact isOpen_iUnion fun s => hf s s.2.1
#align topological_space.is_topological_basis.is_open_map_iff TopologicalSpace.IsTopologicalBasis.isOpenMap_iff
theorem IsTopologicalBasis.exists_nonempty_subset {B : Set (Set α)} (hb : IsTopologicalBasis B)
{u : Set α} (hu : u.Nonempty) (ou : IsOpen u) : ∃ v ∈ B, Set.Nonempty v ∧ v ⊆ u :=
let ⟨x, hx⟩ := hu
let ⟨v, vB, xv, vu⟩ := hb.exists_subset_of_mem_open hx ou
⟨v, vB, ⟨x, xv⟩, vu⟩
#align topological_space.is_topological_basis.exists_nonempty_subset TopologicalSpace.IsTopologicalBasis.exists_nonempty_subset
theorem isTopologicalBasis_opens : IsTopologicalBasis { U : Set α | IsOpen U } :=
isTopologicalBasis_of_isOpen_of_nhds (by tauto) (by tauto)
#align topological_space.is_topological_basis_opens TopologicalSpace.isTopologicalBasis_opens
protected theorem IsTopologicalBasis.inducing {β} [TopologicalSpace β] {f : α → β} {T : Set (Set β)}
(hf : Inducing f) (h : IsTopologicalBasis T) : IsTopologicalBasis ((preimage f) '' T) :=
.of_hasBasis_nhds fun a ↦ by
convert (hf.basis_nhds (h.nhds_hasBasis (a := f a))).to_image_id with s
aesop
#align topological_space.is_topological_basis.inducing TopologicalSpace.IsTopologicalBasis.inducing
protected theorem IsTopologicalBasis.induced [s : TopologicalSpace β] (f : α → β)
{T : Set (Set β)} (h : IsTopologicalBasis T) :
IsTopologicalBasis (t := induced f s) ((preimage f) '' T) :=
h.inducing (t := induced f s) (inducing_induced f)
protected theorem IsTopologicalBasis.inf {t₁ t₂ : TopologicalSpace β} {B₁ B₂ : Set (Set β)}
(h₁ : IsTopologicalBasis (t := t₁) B₁) (h₂ : IsTopologicalBasis (t := t₂) B₂) :
IsTopologicalBasis (t := t₁ ⊓ t₂) (image2 (· ∩ ·) B₁ B₂) := by
refine .of_hasBasis_nhds (t := ?_) fun a ↦ ?_
rw [nhds_inf (t₁ := t₁)]
convert ((h₁.nhds_hasBasis (t := t₁)).inf (h₂.nhds_hasBasis (t := t₂))).to_image_id
aesop
theorem IsTopologicalBasis.inf_induced {γ} [s : TopologicalSpace β] {B₁ : Set (Set α)}
{B₂ : Set (Set β)} (h₁ : IsTopologicalBasis B₁) (h₂ : IsTopologicalBasis B₂) (f₁ : γ → α)
(f₂ : γ → β) :
IsTopologicalBasis (t := induced f₁ t ⊓ induced f₂ s) (image2 (f₁ ⁻¹' · ∩ f₂ ⁻¹' ·) B₁ B₂) := by
simpa only [image2_image_left, image2_image_right] using (h₁.induced f₁).inf (h₂.induced f₂)
protected theorem IsTopologicalBasis.prod {β} [TopologicalSpace β] {B₁ : Set (Set α)}
{B₂ : Set (Set β)} (h₁ : IsTopologicalBasis B₁) (h₂ : IsTopologicalBasis B₂) :
IsTopologicalBasis (image2 (· ×ˢ ·) B₁ B₂) :=
h₁.inf_induced h₂ Prod.fst Prod.snd
#align topological_space.is_topological_basis.prod TopologicalSpace.IsTopologicalBasis.prod
| Mathlib/Topology/Bases.lean | 280 | 293 | theorem isTopologicalBasis_of_cover {ι} {U : ι → Set α} (Uo : ∀ i, IsOpen (U i))
(Uc : ⋃ i, U i = univ) {b : ∀ i, Set (Set (U i))} (hb : ∀ i, IsTopologicalBasis (b i)) :
IsTopologicalBasis (⋃ i : ι, image ((↑) : U i → α) '' b i) := by |
refine isTopologicalBasis_of_isOpen_of_nhds (fun u hu => ?_) ?_
· simp only [mem_iUnion, mem_image] at hu
rcases hu with ⟨i, s, sb, rfl⟩
exact (Uo i).isOpenMap_subtype_val _ ((hb i).isOpen sb)
· intro a u ha uo
rcases iUnion_eq_univ_iff.1 Uc a with ⟨i, hi⟩
lift a to ↥(U i) using hi
rcases (hb i).exists_subset_of_mem_open ha (uo.preimage continuous_subtype_val) with
⟨v, hvb, hav, hvu⟩
exact ⟨(↑) '' v, mem_iUnion.2 ⟨i, mem_image_of_mem _ hvb⟩, mem_image_of_mem _ hav,
image_subset_iff.2 hvu⟩
|
import Mathlib.Analysis.NormedSpace.OperatorNorm.Basic
suppress_compilation
open Bornology
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*}
section SemiNormed
open Metric ContinuousLinearMap
variable [SeminormedAddCommGroup E] [SeminormedAddCommGroup Eₗ] [SeminormedAddCommGroup F]
[SeminormedAddCommGroup Fₗ] [SeminormedAddCommGroup G] [SeminormedAddCommGroup Gₗ]
variable [NontriviallyNormedField 𝕜] [NontriviallyNormedField 𝕜₂] [NontriviallyNormedField 𝕜₃]
[NormedSpace 𝕜 E] [NormedSpace 𝕜 Eₗ] [NormedSpace 𝕜₂ F] [NormedSpace 𝕜 Fₗ] [NormedSpace 𝕜₃ G]
[NormedSpace 𝕜 Gₗ] {σ₁₂ : 𝕜 →+* 𝕜₂} {σ₂₃ : 𝕜₂ →+* 𝕜₃} {σ₁₃ : 𝕜 →+* 𝕜₃}
[RingHomCompTriple σ₁₂ σ₂₃ σ₁₃]
variable [FunLike 𝓕 E F]
namespace ContinuousLinearMap
section OpNorm
open Set Real
section
variable [RingHomIsometric σ₁₂] [RingHomIsometric σ₂₃] (f g : E →SL[σ₁₂] F) (h : F →SL[σ₂₃] G)
(x : E)
theorem nnnorm_def (f : E →SL[σ₁₂] F) : ‖f‖₊ = sInf { c | ∀ x, ‖f x‖₊ ≤ c * ‖x‖₊ } := by
ext
rw [NNReal.coe_sInf, coe_nnnorm, norm_def, NNReal.coe_image]
simp_rw [← NNReal.coe_le_coe, NNReal.coe_mul, coe_nnnorm, mem_setOf_eq, NNReal.coe_mk,
exists_prop]
#align continuous_linear_map.nnnorm_def ContinuousLinearMap.nnnorm_def
theorem opNNNorm_le_bound (f : E →SL[σ₁₂] F) (M : ℝ≥0) (hM : ∀ x, ‖f x‖₊ ≤ M * ‖x‖₊) : ‖f‖₊ ≤ M :=
opNorm_le_bound f (zero_le M) hM
#align continuous_linear_map.op_nnnorm_le_bound ContinuousLinearMap.opNNNorm_le_bound
@[deprecated (since := "2024-02-02")] alias op_nnnorm_le_bound := opNNNorm_le_bound
theorem opNNNorm_le_bound' (f : E →SL[σ₁₂] F) (M : ℝ≥0) (hM : ∀ x, ‖x‖₊ ≠ 0 → ‖f x‖₊ ≤ M * ‖x‖₊) :
‖f‖₊ ≤ M :=
opNorm_le_bound' f (zero_le M) fun x hx => hM x <| by rwa [← NNReal.coe_ne_zero]
#align continuous_linear_map.op_nnnorm_le_bound' ContinuousLinearMap.opNNNorm_le_bound'
@[deprecated (since := "2024-02-02")] alias op_nnnorm_le_bound' := opNNNorm_le_bound'
theorem opNNNorm_le_of_unit_nnnorm [NormedSpace ℝ E] [NormedSpace ℝ F] {f : E →L[ℝ] F} {C : ℝ≥0}
(hf : ∀ x, ‖x‖₊ = 1 → ‖f x‖₊ ≤ C) : ‖f‖₊ ≤ C :=
opNorm_le_of_unit_norm C.coe_nonneg fun x hx => hf x <| by rwa [← NNReal.coe_eq_one]
#align continuous_linear_map.op_nnnorm_le_of_unit_nnnorm ContinuousLinearMap.opNNNorm_le_of_unit_nnnorm
@[deprecated (since := "2024-02-02")]
alias op_nnnorm_le_of_unit_nnnorm := opNNNorm_le_of_unit_nnnorm
theorem opNNNorm_le_of_lipschitz {f : E →SL[σ₁₂] F} {K : ℝ≥0} (hf : LipschitzWith K f) :
‖f‖₊ ≤ K :=
opNorm_le_of_lipschitz hf
#align continuous_linear_map.op_nnnorm_le_of_lipschitz ContinuousLinearMap.opNNNorm_le_of_lipschitz
@[deprecated (since := "2024-02-02")] alias op_nnnorm_le_of_lipschitz := opNNNorm_le_of_lipschitz
theorem opNNNorm_eq_of_bounds {φ : E →SL[σ₁₂] F} (M : ℝ≥0) (h_above : ∀ x, ‖φ x‖₊ ≤ M * ‖x‖₊)
(h_below : ∀ N, (∀ x, ‖φ x‖₊ ≤ N * ‖x‖₊) → M ≤ N) : ‖φ‖₊ = M :=
Subtype.ext <| opNorm_eq_of_bounds (zero_le M) h_above <| Subtype.forall'.mpr h_below
#align continuous_linear_map.op_nnnorm_eq_of_bounds ContinuousLinearMap.opNNNorm_eq_of_bounds
@[deprecated (since := "2024-02-02")] alias op_nnnorm_eq_of_bounds := opNNNorm_eq_of_bounds
theorem opNNNorm_le_iff {f : E →SL[σ₁₂] F} {C : ℝ≥0} : ‖f‖₊ ≤ C ↔ ∀ x, ‖f x‖₊ ≤ C * ‖x‖₊ :=
opNorm_le_iff C.2
@[deprecated (since := "2024-02-02")] alias op_nnnorm_le_iff := opNNNorm_le_iff
| Mathlib/Analysis/NormedSpace/OperatorNorm/NNNorm.lean | 100 | 101 | theorem isLeast_opNNNorm : IsLeast {C : ℝ≥0 | ∀ x, ‖f x‖₊ ≤ C * ‖x‖₊} ‖f‖₊ := by |
simpa only [← opNNNorm_le_iff] using isLeast_Ici
|
import Mathlib.Data.Finset.Order
import Mathlib.Algebra.DirectSum.Module
import Mathlib.RingTheory.FreeCommRing
import Mathlib.RingTheory.Ideal.Maps
import Mathlib.RingTheory.Ideal.Quotient
import Mathlib.Tactic.SuppressCompilation
#align_import algebra.direct_limit from "leanprover-community/mathlib"@"f0c8bf9245297a541f468be517f1bde6195105e9"
suppress_compilation
universe u v v' v'' w u₁
open Submodule
variable {R : Type u} [Ring R]
variable {ι : Type v}
variable [Preorder ι]
variable (G : ι → Type w)
class DirectedSystem (f : ∀ i j, i ≤ j → G i → G j) : Prop where
map_self' : ∀ i x h, f i i h x = x
map_map' : ∀ {i j k} (hij hjk x), f j k hjk (f i j hij x) = f i k (le_trans hij hjk) x
#align directed_system DirectedSystem
section
variable {G} (f : ∀ i j, i ≤ j → G i → G j) [DirectedSystem G fun i j h => f i j h]
theorem DirectedSystem.map_self i x h : f i i h x = x :=
DirectedSystem.map_self' i x h
theorem DirectedSystem.map_map {i j k} (hij hjk x) :
f j k hjk (f i j hij x) = f i k (le_trans hij hjk) x :=
DirectedSystem.map_map' hij hjk x
end
namespace Module
variable [∀ i, AddCommGroup (G i)] [∀ i, Module R (G i)]
variable {G} (f : ∀ i j, i ≤ j → G i →ₗ[R] G j)
nonrec theorem DirectedSystem.map_self [DirectedSystem G fun i j h => f i j h] (i x h) :
f i i h x = x :=
DirectedSystem.map_self (fun i j h => f i j h) i x h
#align module.directed_system.map_self Module.DirectedSystem.map_self
nonrec theorem DirectedSystem.map_map [DirectedSystem G fun i j h => f i j h] {i j k} (hij hjk x) :
f j k hjk (f i j hij x) = f i k (le_trans hij hjk) x :=
DirectedSystem.map_map (fun i j h => f i j h) hij hjk x
#align module.directed_system.map_map Module.DirectedSystem.map_map
variable (G)
variable [DecidableEq ι]
def DirectLimit : Type max v w :=
DirectSum ι G ⧸
(span R <|
{ a |
∃ (i j : _) (H : i ≤ j) (x : _),
DirectSum.lof R ι G i x - DirectSum.lof R ι G j (f i j H x) = a })
#align module.direct_limit Module.DirectLimit
namespace DirectLimit
instance addCommGroup : AddCommGroup (DirectLimit G f) :=
Quotient.addCommGroup _
instance module : Module R (DirectLimit G f) :=
Quotient.module _
instance inhabited : Inhabited (DirectLimit G f) :=
⟨0⟩
instance unique [IsEmpty ι] : Unique (DirectLimit G f) :=
inferInstanceAs <| Unique (Quotient _)
variable (R ι)
def of (i) : G i →ₗ[R] DirectLimit G f :=
(mkQ _).comp <| DirectSum.lof R ι G i
#align module.direct_limit.of Module.DirectLimit.of
variable {R ι G f}
@[simp]
theorem of_f {i j hij x} : of R ι G f j (f i j hij x) = of R ι G f i x :=
Eq.symm <| (Submodule.Quotient.eq _).2 <| subset_span ⟨i, j, hij, x, rfl⟩
#align module.direct_limit.of_f Module.DirectLimit.of_f
theorem exists_of [Nonempty ι] [IsDirected ι (· ≤ ·)] (z : DirectLimit G f) :
∃ i x, of R ι G f i x = z :=
Nonempty.elim (by infer_instance) fun ind : ι =>
Quotient.inductionOn' z fun z =>
DirectSum.induction_on z ⟨ind, 0, LinearMap.map_zero _⟩ (fun i x => ⟨i, x, rfl⟩)
fun p q ⟨i, x, ihx⟩ ⟨j, y, ihy⟩ =>
let ⟨k, hik, hjk⟩ := exists_ge_ge i j
⟨k, f i k hik x + f j k hjk y, by
rw [LinearMap.map_add, of_f, of_f, ihx, ihy]
rfl ⟩
#align module.direct_limit.exists_of Module.DirectLimit.exists_of
@[elab_as_elim]
protected theorem induction_on [Nonempty ι] [IsDirected ι (· ≤ ·)] {C : DirectLimit G f → Prop}
(z : DirectLimit G f) (ih : ∀ i x, C (of R ι G f i x)) : C z :=
let ⟨i, x, h⟩ := exists_of z
h ▸ ih i x
#align module.direct_limit.induction_on Module.DirectLimit.induction_on
variable {P : Type u₁} [AddCommGroup P] [Module R P] (g : ∀ i, G i →ₗ[R] P)
variable (Hg : ∀ i j hij x, g j (f i j hij x) = g i x)
variable (R ι G f)
def lift : DirectLimit G f →ₗ[R] P :=
liftQ _ (DirectSum.toModule R ι P g)
(span_le.2 fun a ⟨i, j, hij, x, hx⟩ => by
rw [← hx, SetLike.mem_coe, LinearMap.sub_mem_ker_iff, DirectSum.toModule_lof,
DirectSum.toModule_lof, Hg])
#align module.direct_limit.lift Module.DirectLimit.lift
variable {R ι G f}
theorem lift_of {i} (x) : lift R ι G f g Hg (of R ι G f i x) = g i x :=
DirectSum.toModule_lof R _ _
#align module.direct_limit.lift_of Module.DirectLimit.lift_of
| Mathlib/Algebra/DirectLimit.lean | 164 | 170 | theorem lift_unique [IsDirected ι (· ≤ ·)] (F : DirectLimit G f →ₗ[R] P) (x) :
F x =
lift R ι G f (fun i => F.comp <| of R ι G f i)
(fun i j hij x => by rw [LinearMap.comp_apply, of_f]; rfl) x := by |
cases isEmpty_or_nonempty ι
· simp_rw [Subsingleton.elim x 0, _root_.map_zero]
· exact DirectLimit.induction_on x fun i x => by rw [lift_of]; rfl
|
import Mathlib.Algebra.BigOperators.Group.Multiset
import Mathlib.Data.PNat.Prime
import Mathlib.Data.Nat.Factors
import Mathlib.Data.Multiset.Sort
#align_import data.pnat.factors from "leanprover-community/mathlib"@"e3d9ab8faa9dea8f78155c6c27d62a621f4c152d"
-- Porting note: `deriving` contained Inhabited, CanonicallyOrderedAddCommMonoid, DistribLattice,
-- SemilatticeSup, OrderBot, Sub, OrderedSub
def PrimeMultiset :=
Multiset Nat.Primes deriving Inhabited, CanonicallyOrderedAddCommMonoid, DistribLattice,
SemilatticeSup, Sub
#align prime_multiset PrimeMultiset
instance : OrderBot PrimeMultiset where
bot_le := by simp only [bot_le, forall_const]
instance : OrderedSub PrimeMultiset where
tsub_le_iff_right _ _ _ := Multiset.sub_le_iff_le_add
namespace PrimeMultiset
-- `@[derive]` doesn't work for `meta` instances
unsafe instance : Repr PrimeMultiset := by delta PrimeMultiset; infer_instance
def ofPrime (p : Nat.Primes) : PrimeMultiset :=
({p} : Multiset Nat.Primes)
#align prime_multiset.of_prime PrimeMultiset.ofPrime
theorem card_ofPrime (p : Nat.Primes) : Multiset.card (ofPrime p) = 1 :=
rfl
#align prime_multiset.card_of_prime PrimeMultiset.card_ofPrime
def toNatMultiset : PrimeMultiset → Multiset ℕ := fun v => v.map Coe.coe
#align prime_multiset.to_nat_multiset PrimeMultiset.toNatMultiset
instance coeNat : Coe PrimeMultiset (Multiset ℕ) :=
⟨toNatMultiset⟩
#align prime_multiset.coe_nat PrimeMultiset.coeNat
def coeNatMonoidHom : PrimeMultiset →+ Multiset ℕ :=
{ Multiset.mapAddMonoidHom Coe.coe with toFun := Coe.coe }
#align prime_multiset.coe_nat_monoid_hom PrimeMultiset.coeNatMonoidHom
@[simp]
theorem coe_coeNatMonoidHom : (coeNatMonoidHom : PrimeMultiset → Multiset ℕ) = Coe.coe :=
rfl
#align prime_multiset.coe_coe_nat_monoid_hom PrimeMultiset.coe_coeNatMonoidHom
theorem coeNat_injective : Function.Injective (Coe.coe : PrimeMultiset → Multiset ℕ) :=
Multiset.map_injective Nat.Primes.coe_nat_injective
#align prime_multiset.coe_nat_injective PrimeMultiset.coeNat_injective
theorem coeNat_ofPrime (p : Nat.Primes) : (ofPrime p : Multiset ℕ) = {(p : ℕ)} :=
rfl
#align prime_multiset.coe_nat_of_prime PrimeMultiset.coeNat_ofPrime
theorem coeNat_prime (v : PrimeMultiset) (p : ℕ) (h : p ∈ (v : Multiset ℕ)) : p.Prime := by
rcases Multiset.mem_map.mp h with ⟨⟨_, hp'⟩, ⟨_, h_eq⟩⟩
exact h_eq ▸ hp'
#align prime_multiset.coe_nat_prime PrimeMultiset.coeNat_prime
def toPNatMultiset : PrimeMultiset → Multiset ℕ+ := fun v => v.map Coe.coe
#align prime_multiset.to_pnat_multiset PrimeMultiset.toPNatMultiset
instance coePNat : Coe PrimeMultiset (Multiset ℕ+) :=
⟨toPNatMultiset⟩
#align prime_multiset.coe_pnat PrimeMultiset.coePNat
def coePNatMonoidHom : PrimeMultiset →+ Multiset ℕ+ :=
{ Multiset.mapAddMonoidHom Coe.coe with toFun := Coe.coe }
#align prime_multiset.coe_pnat_monoid_hom PrimeMultiset.coePNatMonoidHom
@[simp]
theorem coe_coePNatMonoidHom : (coePNatMonoidHom : PrimeMultiset → Multiset ℕ+) = Coe.coe :=
rfl
#align prime_multiset.coe_coe_pnat_monoid_hom PrimeMultiset.coe_coePNatMonoidHom
theorem coePNat_injective : Function.Injective (Coe.coe : PrimeMultiset → Multiset ℕ+) :=
Multiset.map_injective Nat.Primes.coe_pnat_injective
#align prime_multiset.coe_pnat_injective PrimeMultiset.coePNat_injective
theorem coePNat_ofPrime (p : Nat.Primes) : (ofPrime p : Multiset ℕ+) = {(p : ℕ+)} :=
rfl
#align prime_multiset.coe_pnat_of_prime PrimeMultiset.coePNat_ofPrime
theorem coePNat_prime (v : PrimeMultiset) (p : ℕ+) (h : p ∈ (v : Multiset ℕ+)) : p.Prime := by
rcases Multiset.mem_map.mp h with ⟨⟨_, hp'⟩, ⟨_, h_eq⟩⟩
exact h_eq ▸ hp'
#align prime_multiset.coe_pnat_prime PrimeMultiset.coePNat_prime
instance coeMultisetPNatNat : Coe (Multiset ℕ+) (Multiset ℕ) :=
⟨fun v => v.map Coe.coe⟩
#align prime_multiset.coe_multiset_pnat_nat PrimeMultiset.coeMultisetPNatNat
theorem coePNat_nat (v : PrimeMultiset) : ((v : Multiset ℕ+) : Multiset ℕ) = (v : Multiset ℕ) := by
change (v.map (Coe.coe : Nat.Primes → ℕ+)).map Subtype.val = v.map Subtype.val
rw [Multiset.map_map]
congr
#align prime_multiset.coe_pnat_nat PrimeMultiset.coePNat_nat
def prod (v : PrimeMultiset) : ℕ+ :=
(v : Multiset PNat).prod
#align prime_multiset.prod PrimeMultiset.prod
theorem coe_prod (v : PrimeMultiset) : (v.prod : ℕ) = (v : Multiset ℕ).prod := by
let h : (v.prod : ℕ) = ((v.map Coe.coe).map Coe.coe).prod :=
PNat.coeMonoidHom.map_multiset_prod v.toPNatMultiset
rw [Multiset.map_map] at h
have : (Coe.coe : ℕ+ → ℕ) ∘ (Coe.coe : Nat.Primes → ℕ+) = Coe.coe := funext fun p => rfl
rw [this] at h; exact h
#align prime_multiset.coe_prod PrimeMultiset.coe_prod
theorem prod_ofPrime (p : Nat.Primes) : (ofPrime p).prod = (p : ℕ+) :=
Multiset.prod_singleton _
#align prime_multiset.prod_of_prime PrimeMultiset.prod_ofPrime
def ofNatMultiset (v : Multiset ℕ) (h : ∀ p : ℕ, p ∈ v → p.Prime) : PrimeMultiset :=
@Multiset.pmap ℕ Nat.Primes Nat.Prime (fun p hp => ⟨p, hp⟩) v h
#align prime_multiset.of_nat_multiset PrimeMultiset.ofNatMultiset
theorem to_ofNatMultiset (v : Multiset ℕ) (h) : (ofNatMultiset v h : Multiset ℕ) = v := by
dsimp [ofNatMultiset, toNatMultiset]
have : (fun p h => (Coe.coe : Nat.Primes → ℕ) ⟨p, h⟩) = fun p _ => id p := by
funext p h
rfl
rw [Multiset.map_pmap, this, Multiset.pmap_eq_map, Multiset.map_id]
#align prime_multiset.to_of_nat_multiset PrimeMultiset.to_ofNatMultiset
| Mathlib/Data/PNat/Factors.lean | 166 | 167 | theorem prod_ofNatMultiset (v : Multiset ℕ) (h) :
((ofNatMultiset v h).prod : ℕ) = (v.prod : ℕ) := by | rw [coe_prod, to_ofNatMultiset]
|
import Mathlib.MeasureTheory.Measure.NullMeasurable
import Mathlib.MeasureTheory.MeasurableSpace.Basic
import Mathlib.Topology.Algebra.Order.LiminfLimsup
#align_import measure_theory.measure.measure_space from "leanprover-community/mathlib"@"343e80208d29d2d15f8050b929aa50fe4ce71b55"
noncomputable section
open Set
open Filter hiding map
open Function MeasurableSpace
open scoped Classical symmDiff
open Topology Filter ENNReal NNReal Interval MeasureTheory
variable {α β γ δ ι R R' : Type*}
namespace MeasureTheory
section
variable {m : MeasurableSpace α} {μ μ₁ μ₂ : Measure α} {s s₁ s₂ t : Set α}
instance ae_isMeasurablyGenerated : IsMeasurablyGenerated (ae μ) :=
⟨fun _s hs =>
let ⟨t, hst, htm, htμ⟩ := exists_measurable_superset_of_null hs
⟨tᶜ, compl_mem_ae_iff.2 htμ, htm.compl, compl_subset_comm.1 hst⟩⟩
#align measure_theory.ae_is_measurably_generated MeasureTheory.ae_isMeasurablyGenerated
theorem ae_uIoc_iff [LinearOrder α] {a b : α} {P : α → Prop} :
(∀ᵐ x ∂μ, x ∈ Ι a b → P x) ↔ (∀ᵐ x ∂μ, x ∈ Ioc a b → P x) ∧ ∀ᵐ x ∂μ, x ∈ Ioc b a → P x := by
simp only [uIoc_eq_union, mem_union, or_imp, eventually_and]
#align measure_theory.ae_uIoc_iff MeasureTheory.ae_uIoc_iff
theorem measure_union (hd : Disjoint s₁ s₂) (h : MeasurableSet s₂) : μ (s₁ ∪ s₂) = μ s₁ + μ s₂ :=
measure_union₀ h.nullMeasurableSet hd.aedisjoint
#align measure_theory.measure_union MeasureTheory.measure_union
theorem measure_union' (hd : Disjoint s₁ s₂) (h : MeasurableSet s₁) : μ (s₁ ∪ s₂) = μ s₁ + μ s₂ :=
measure_union₀' h.nullMeasurableSet hd.aedisjoint
#align measure_theory.measure_union' MeasureTheory.measure_union'
theorem measure_inter_add_diff (s : Set α) (ht : MeasurableSet t) : μ (s ∩ t) + μ (s \ t) = μ s :=
measure_inter_add_diff₀ _ ht.nullMeasurableSet
#align measure_theory.measure_inter_add_diff MeasureTheory.measure_inter_add_diff
theorem measure_diff_add_inter (s : Set α) (ht : MeasurableSet t) : μ (s \ t) + μ (s ∩ t) = μ s :=
(add_comm _ _).trans (measure_inter_add_diff s ht)
#align measure_theory.measure_diff_add_inter MeasureTheory.measure_diff_add_inter
theorem measure_union_add_inter (s : Set α) (ht : MeasurableSet t) :
μ (s ∪ t) + μ (s ∩ t) = μ s + μ t := by
rw [← measure_inter_add_diff (s ∪ t) ht, Set.union_inter_cancel_right, union_diff_right, ←
measure_inter_add_diff s ht]
ac_rfl
#align measure_theory.measure_union_add_inter MeasureTheory.measure_union_add_inter
theorem measure_union_add_inter' (hs : MeasurableSet s) (t : Set α) :
μ (s ∪ t) + μ (s ∩ t) = μ s + μ t := by
rw [union_comm, inter_comm, measure_union_add_inter t hs, add_comm]
#align measure_theory.measure_union_add_inter' MeasureTheory.measure_union_add_inter'
lemma measure_symmDiff_eq (hs : MeasurableSet s) (ht : MeasurableSet t) :
μ (s ∆ t) = μ (s \ t) + μ (t \ s) := by
simpa only [symmDiff_def, sup_eq_union] using measure_union disjoint_sdiff_sdiff (ht.diff hs)
lemma measure_symmDiff_le (s t u : Set α) :
μ (s ∆ u) ≤ μ (s ∆ t) + μ (t ∆ u) :=
le_trans (μ.mono <| symmDiff_triangle s t u) (measure_union_le (s ∆ t) (t ∆ u))
theorem measure_add_measure_compl (h : MeasurableSet s) : μ s + μ sᶜ = μ univ :=
measure_add_measure_compl₀ h.nullMeasurableSet
#align measure_theory.measure_add_measure_compl MeasureTheory.measure_add_measure_compl
theorem measure_biUnion₀ {s : Set β} {f : β → Set α} (hs : s.Countable)
(hd : s.Pairwise (AEDisjoint μ on f)) (h : ∀ b ∈ s, NullMeasurableSet (f b) μ) :
μ (⋃ b ∈ s, f b) = ∑' p : s, μ (f p) := by
haveI := hs.toEncodable
rw [biUnion_eq_iUnion]
exact measure_iUnion₀ (hd.on_injective Subtype.coe_injective fun x => x.2) fun x => h x x.2
#align measure_theory.measure_bUnion₀ MeasureTheory.measure_biUnion₀
theorem measure_biUnion {s : Set β} {f : β → Set α} (hs : s.Countable) (hd : s.PairwiseDisjoint f)
(h : ∀ b ∈ s, MeasurableSet (f b)) : μ (⋃ b ∈ s, f b) = ∑' p : s, μ (f p) :=
measure_biUnion₀ hs hd.aedisjoint fun b hb => (h b hb).nullMeasurableSet
#align measure_theory.measure_bUnion MeasureTheory.measure_biUnion
theorem measure_sUnion₀ {S : Set (Set α)} (hs : S.Countable) (hd : S.Pairwise (AEDisjoint μ))
(h : ∀ s ∈ S, NullMeasurableSet s μ) : μ (⋃₀ S) = ∑' s : S, μ s := by
rw [sUnion_eq_biUnion, measure_biUnion₀ hs hd h]
#align measure_theory.measure_sUnion₀ MeasureTheory.measure_sUnion₀
theorem measure_sUnion {S : Set (Set α)} (hs : S.Countable) (hd : S.Pairwise Disjoint)
(h : ∀ s ∈ S, MeasurableSet s) : μ (⋃₀ S) = ∑' s : S, μ s := by
rw [sUnion_eq_biUnion, measure_biUnion hs hd h]
#align measure_theory.measure_sUnion MeasureTheory.measure_sUnion
theorem measure_biUnion_finset₀ {s : Finset ι} {f : ι → Set α}
(hd : Set.Pairwise (↑s) (AEDisjoint μ on f)) (hm : ∀ b ∈ s, NullMeasurableSet (f b) μ) :
μ (⋃ b ∈ s, f b) = ∑ p ∈ s, μ (f p) := by
rw [← Finset.sum_attach, Finset.attach_eq_univ, ← tsum_fintype]
exact measure_biUnion₀ s.countable_toSet hd hm
#align measure_theory.measure_bUnion_finset₀ MeasureTheory.measure_biUnion_finset₀
theorem measure_biUnion_finset {s : Finset ι} {f : ι → Set α} (hd : PairwiseDisjoint (↑s) f)
(hm : ∀ b ∈ s, MeasurableSet (f b)) : μ (⋃ b ∈ s, f b) = ∑ p ∈ s, μ (f p) :=
measure_biUnion_finset₀ hd.aedisjoint fun b hb => (hm b hb).nullMeasurableSet
#align measure_theory.measure_bUnion_finset MeasureTheory.measure_biUnion_finset
theorem tsum_meas_le_meas_iUnion_of_disjoint₀ {ι : Type*} [MeasurableSpace α] (μ : Measure α)
{As : ι → Set α} (As_mble : ∀ i : ι, NullMeasurableSet (As i) μ)
(As_disj : Pairwise (AEDisjoint μ on As)) : (∑' i, μ (As i)) ≤ μ (⋃ i, As i) := by
rw [ENNReal.tsum_eq_iSup_sum, iSup_le_iff]
intro s
simp only [← measure_biUnion_finset₀ (fun _i _hi _j _hj hij => As_disj hij) fun i _ => As_mble i]
gcongr
exact iUnion_subset fun _ ↦ Subset.rfl
theorem tsum_meas_le_meas_iUnion_of_disjoint {ι : Type*} [MeasurableSpace α] (μ : Measure α)
{As : ι → Set α} (As_mble : ∀ i : ι, MeasurableSet (As i))
(As_disj : Pairwise (Disjoint on As)) : (∑' i, μ (As i)) ≤ μ (⋃ i, As i) :=
tsum_meas_le_meas_iUnion_of_disjoint₀ μ (fun i ↦ (As_mble i).nullMeasurableSet)
(fun _ _ h ↦ Disjoint.aedisjoint (As_disj h))
#align measure_theory.tsum_meas_le_meas_Union_of_disjoint MeasureTheory.tsum_meas_le_meas_iUnion_of_disjoint
theorem tsum_measure_preimage_singleton {s : Set β} (hs : s.Countable) {f : α → β}
(hf : ∀ y ∈ s, MeasurableSet (f ⁻¹' {y})) : (∑' b : s, μ (f ⁻¹' {↑b})) = μ (f ⁻¹' s) := by
rw [← Set.biUnion_preimage_singleton, measure_biUnion hs (pairwiseDisjoint_fiber f s) hf]
#align measure_theory.tsum_measure_preimage_singleton MeasureTheory.tsum_measure_preimage_singleton
lemma measure_preimage_eq_zero_iff_of_countable {s : Set β} {f : α → β} (hs : s.Countable) :
μ (f ⁻¹' s) = 0 ↔ ∀ x ∈ s, μ (f ⁻¹' {x}) = 0 := by
rw [← biUnion_preimage_singleton, measure_biUnion_null_iff hs]
theorem sum_measure_preimage_singleton (s : Finset β) {f : α → β}
(hf : ∀ y ∈ s, MeasurableSet (f ⁻¹' {y})) : (∑ b ∈ s, μ (f ⁻¹' {b})) = μ (f ⁻¹' ↑s) := by
simp only [← measure_biUnion_finset (pairwiseDisjoint_fiber f s) hf,
Finset.set_biUnion_preimage_singleton]
#align measure_theory.sum_measure_preimage_singleton MeasureTheory.sum_measure_preimage_singleton
theorem measure_diff_null' (h : μ (s₁ ∩ s₂) = 0) : μ (s₁ \ s₂) = μ s₁ :=
measure_congr <| diff_ae_eq_self.2 h
#align measure_theory.measure_diff_null' MeasureTheory.measure_diff_null'
| Mathlib/MeasureTheory/Measure/MeasureSpace.lean | 230 | 231 | theorem measure_add_diff (hs : MeasurableSet s) (t : Set α) : μ s + μ (t \ s) = μ (s ∪ t) := by |
rw [← measure_union' disjoint_sdiff_right hs, union_diff_self]
|
import Mathlib.Algebra.CharP.Invertible
import Mathlib.Analysis.NormedSpace.Basic
import Mathlib.Analysis.Normed.Group.AddTorsor
import Mathlib.LinearAlgebra.AffineSpace.AffineSubspace
import Mathlib.Topology.Instances.RealVectorSpace
#align_import analysis.normed_space.add_torsor from "leanprover-community/mathlib"@"837f72de63ad6cd96519cde5f1ffd5ed8d280ad0"
noncomputable section
open NNReal Topology
open Filter
variable {α V P W Q : Type*} [SeminormedAddCommGroup V] [PseudoMetricSpace P] [NormedAddTorsor V P]
[NormedAddCommGroup W] [MetricSpace Q] [NormedAddTorsor W Q]
section NormedSpace
variable {𝕜 : Type*} [NormedField 𝕜] [NormedSpace 𝕜 V] [NormedSpace 𝕜 W]
open AffineMap
theorem AffineSubspace.isClosed_direction_iff (s : AffineSubspace 𝕜 Q) :
IsClosed (s.direction : Set W) ↔ IsClosed (s : Set Q) := by
rcases s.eq_bot_or_nonempty with (rfl | ⟨x, hx⟩); · simp [isClosed_singleton]
rw [← (IsometryEquiv.vaddConst x).toHomeomorph.symm.isClosed_image,
AffineSubspace.coe_direction_eq_vsub_set_right hx]
rfl
#align affine_subspace.is_closed_direction_iff AffineSubspace.isClosed_direction_iff
@[simp]
theorem dist_center_homothety (p₁ p₂ : P) (c : 𝕜) :
dist p₁ (homothety p₁ c p₂) = ‖c‖ * dist p₁ p₂ := by
simp [homothety_def, norm_smul, ← dist_eq_norm_vsub, dist_comm]
#align dist_center_homothety dist_center_homothety
@[simp]
theorem nndist_center_homothety (p₁ p₂ : P) (c : 𝕜) :
nndist p₁ (homothety p₁ c p₂) = ‖c‖₊ * nndist p₁ p₂ :=
NNReal.eq <| dist_center_homothety _ _ _
#align nndist_center_homothety nndist_center_homothety
@[simp]
theorem dist_homothety_center (p₁ p₂ : P) (c : 𝕜) :
dist (homothety p₁ c p₂) p₁ = ‖c‖ * dist p₁ p₂ := by rw [dist_comm, dist_center_homothety]
#align dist_homothety_center dist_homothety_center
@[simp]
theorem nndist_homothety_center (p₁ p₂ : P) (c : 𝕜) :
nndist (homothety p₁ c p₂) p₁ = ‖c‖₊ * nndist p₁ p₂ :=
NNReal.eq <| dist_homothety_center _ _ _
#align nndist_homothety_center nndist_homothety_center
@[simp]
| Mathlib/Analysis/NormedSpace/AddTorsor.lean | 68 | 72 | theorem dist_lineMap_lineMap (p₁ p₂ : P) (c₁ c₂ : 𝕜) :
dist (lineMap p₁ p₂ c₁) (lineMap p₁ p₂ c₂) = dist c₁ c₂ * dist p₁ p₂ := by |
rw [dist_comm p₁ p₂]
simp only [lineMap_apply, dist_eq_norm_vsub, vadd_vsub_vadd_cancel_right,
← sub_smul, norm_smul, vsub_eq_sub]
|
import Mathlib.CategoryTheory.Sites.Sheaf
#align_import category_theory.sites.plus from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a"
namespace CategoryTheory.GrothendieckTopology
open CategoryTheory
open CategoryTheory.Limits
open Opposite
universe w v u
variable {C : Type u} [Category.{v} C] (J : GrothendieckTopology C)
variable {D : Type w} [Category.{max v u} D]
noncomputable section
variable [∀ (P : Cᵒᵖ ⥤ D) (X : C) (S : J.Cover X), HasMultiequalizer (S.index P)]
variable (P : Cᵒᵖ ⥤ D)
@[simps]
def diagram (X : C) : (J.Cover X)ᵒᵖ ⥤ D where
obj S := multiequalizer (S.unop.index P)
map {S _} f :=
Multiequalizer.lift _ _ (fun I => Multiequalizer.ι (S.unop.index P) (I.map f.unop)) fun I =>
Multiequalizer.condition (S.unop.index P) (I.map f.unop)
#align category_theory.grothendieck_topology.diagram CategoryTheory.GrothendieckTopology.diagram
@[simps]
def diagramPullback {X Y : C} (f : X ⟶ Y) : J.diagram P Y ⟶ (J.pullback f).op ⋙ J.diagram P X where
app S :=
Multiequalizer.lift _ _ (fun I => Multiequalizer.ι (S.unop.index P) I.base) fun I =>
Multiequalizer.condition (S.unop.index P) I.base
naturality S T f := Multiequalizer.hom_ext _ _ _ (fun I => by dsimp; simp; rfl)
#align category_theory.grothendieck_topology.diagram_pullback CategoryTheory.GrothendieckTopology.diagramPullback
@[simps]
def diagramNatTrans {P Q : Cᵒᵖ ⥤ D} (η : P ⟶ Q) (X : C) : J.diagram P X ⟶ J.diagram Q X where
app W :=
Multiequalizer.lift _ _ (fun i => Multiequalizer.ι _ _ ≫ η.app _) (fun i => by
dsimp only
erw [Category.assoc, Category.assoc, ← η.naturality, ← η.naturality,
Multiequalizer.condition_assoc]
rfl)
#align category_theory.grothendieck_topology.diagram_nat_trans CategoryTheory.GrothendieckTopology.diagramNatTrans
@[simp]
| Mathlib/CategoryTheory/Sites/Plus.lean | 71 | 77 | theorem diagramNatTrans_id (X : C) (P : Cᵒᵖ ⥤ D) :
J.diagramNatTrans (𝟙 P) X = 𝟙 (J.diagram P X) := by |
ext : 2
refine Multiequalizer.hom_ext _ _ _ (fun i => ?_)
dsimp
simp only [limit.lift_π, Multifork.ofι_pt, Multifork.ofι_π_app, Category.id_comp]
erw [Category.comp_id]
|
import Mathlib.CategoryTheory.PEmpty
import Mathlib.CategoryTheory.Limits.HasLimits
import Mathlib.CategoryTheory.EpiMono
import Mathlib.CategoryTheory.Category.Preorder
#align_import category_theory.limits.shapes.terminal from "leanprover-community/mathlib"@"239d882c4fb58361ee8b3b39fb2091320edef10a"
noncomputable section
universe w w' v v₁ v₂ u u₁ u₂
open CategoryTheory
namespace CategoryTheory.Limits
variable {C : Type u₁} [Category.{v₁} C]
@[simps]
def asEmptyCone (X : C) : Cone (Functor.empty.{0} C) :=
{ pt := X
π :=
{ app := by aesop_cat } }
#align category_theory.limits.as_empty_cone CategoryTheory.Limits.asEmptyCone
@[simps]
def asEmptyCocone (X : C) : Cocone (Functor.empty.{0} C) :=
{ pt := X
ι :=
{ app := by aesop_cat } }
#align category_theory.limits.as_empty_cocone CategoryTheory.Limits.asEmptyCocone
abbrev IsTerminal (X : C) :=
IsLimit (asEmptyCone X)
#align category_theory.limits.is_terminal CategoryTheory.Limits.IsTerminal
abbrev IsInitial (X : C) :=
IsColimit (asEmptyCocone X)
#align category_theory.limits.is_initial CategoryTheory.Limits.IsInitial
def isTerminalEquivUnique (F : Discrete.{0} PEmpty.{1} ⥤ C) (Y : C) :
IsLimit (⟨Y, by aesop_cat, by aesop_cat⟩ : Cone F) ≃ ∀ X : C, Unique (X ⟶ Y) where
toFun t X :=
{ default := t.lift ⟨X, ⟨by aesop_cat, by aesop_cat⟩⟩
uniq := fun f =>
t.uniq ⟨X, ⟨by aesop_cat, by aesop_cat⟩⟩ f (by aesop_cat) }
invFun u :=
{ lift := fun s => (u s.pt).default
uniq := fun s _ _ => (u s.pt).2 _ }
left_inv := by dsimp [Function.LeftInverse]; intro x; simp only [eq_iff_true_of_subsingleton]
right_inv := by
dsimp [Function.RightInverse,Function.LeftInverse]
intro u; funext X; simp only
#align category_theory.limits.is_terminal_equiv_unique CategoryTheory.Limits.isTerminalEquivUnique
def IsTerminal.ofUnique (Y : C) [h : ∀ X : C, Unique (X ⟶ Y)] : IsTerminal Y where
lift s := (h s.pt).default
fac := fun _ ⟨j⟩ => j.elim
#align category_theory.limits.is_terminal.of_unique CategoryTheory.Limits.IsTerminal.ofUnique
def IsTerminal.ofUniqueHom {Y : C} (h : ∀ X : C, X ⟶ Y) (uniq : ∀ (X : C) (m : X ⟶ Y), m = h X) :
IsTerminal Y :=
have : ∀ X : C, Unique (X ⟶ Y) := fun X ↦ ⟨⟨h X⟩, uniq X⟩
IsTerminal.ofUnique Y
def isTerminalTop {α : Type*} [Preorder α] [OrderTop α] : IsTerminal (⊤ : α) :=
IsTerminal.ofUnique _
#align category_theory.limits.is_terminal_top CategoryTheory.Limits.isTerminalTop
def IsTerminal.ofIso {Y Z : C} (hY : IsTerminal Y) (i : Y ≅ Z) : IsTerminal Z :=
IsLimit.ofIsoLimit hY
{ hom := { hom := i.hom }
inv := { hom := i.inv } }
#align category_theory.limits.is_terminal.of_iso CategoryTheory.Limits.IsTerminal.ofIso
def IsTerminal.equivOfIso {X Y : C} (e : X ≅ Y) :
IsTerminal X ≃ IsTerminal Y where
toFun h := IsTerminal.ofIso h e
invFun h := IsTerminal.ofIso h e.symm
left_inv _ := Subsingleton.elim _ _
right_inv _ := Subsingleton.elim _ _
def isInitialEquivUnique (F : Discrete.{0} PEmpty.{1} ⥤ C) (X : C) :
IsColimit (⟨X, ⟨by aesop_cat, by aesop_cat⟩⟩ : Cocone F) ≃ ∀ Y : C, Unique (X ⟶ Y) where
toFun t X :=
{ default := t.desc ⟨X, ⟨by aesop_cat, by aesop_cat⟩⟩
uniq := fun f => t.uniq ⟨X, ⟨by aesop_cat, by aesop_cat⟩⟩ f (by aesop_cat) }
invFun u :=
{ desc := fun s => (u s.pt).default
uniq := fun s _ _ => (u s.pt).2 _ }
left_inv := by dsimp [Function.LeftInverse]; intro; simp only [eq_iff_true_of_subsingleton]
right_inv := by
dsimp [Function.RightInverse,Function.LeftInverse]
intro; funext; simp only
#align category_theory.limits.is_initial_equiv_unique CategoryTheory.Limits.isInitialEquivUnique
def IsInitial.ofUnique (X : C) [h : ∀ Y : C, Unique (X ⟶ Y)] : IsInitial X where
desc s := (h s.pt).default
fac := fun _ ⟨j⟩ => j.elim
#align category_theory.limits.is_initial.of_unique CategoryTheory.Limits.IsInitial.ofUnique
def IsInitial.ofUniqueHom {X : C} (h : ∀ Y : C, X ⟶ Y) (uniq : ∀ (Y : C) (m : X ⟶ Y), m = h Y) :
IsInitial X :=
have : ∀ Y : C, Unique (X ⟶ Y) := fun Y ↦ ⟨⟨h Y⟩, uniq Y⟩
IsInitial.ofUnique X
def isInitialBot {α : Type*} [Preorder α] [OrderBot α] : IsInitial (⊥ : α) :=
IsInitial.ofUnique _
#align category_theory.limits.is_initial_bot CategoryTheory.Limits.isInitialBot
def IsInitial.ofIso {X Y : C} (hX : IsInitial X) (i : X ≅ Y) : IsInitial Y :=
IsColimit.ofIsoColimit hX
{ hom := { hom := i.hom }
inv := { hom := i.inv } }
#align category_theory.limits.is_initial.of_iso CategoryTheory.Limits.IsInitial.ofIso
def IsInitial.equivOfIso {X Y : C} (e : X ≅ Y) :
IsInitial X ≃ IsInitial Y where
toFun h := IsInitial.ofIso h e
invFun h := IsInitial.ofIso h e.symm
left_inv _ := Subsingleton.elim _ _
right_inv _ := Subsingleton.elim _ _
def IsTerminal.from {X : C} (t : IsTerminal X) (Y : C) : Y ⟶ X :=
t.lift (asEmptyCone Y)
#align category_theory.limits.is_terminal.from CategoryTheory.Limits.IsTerminal.from
theorem IsTerminal.hom_ext {X Y : C} (t : IsTerminal X) (f g : Y ⟶ X) : f = g :=
IsLimit.hom_ext t (by aesop_cat)
#align category_theory.limits.is_terminal.hom_ext CategoryTheory.Limits.IsTerminal.hom_ext
@[simp]
theorem IsTerminal.comp_from {Z : C} (t : IsTerminal Z) {X Y : C} (f : X ⟶ Y) :
f ≫ t.from Y = t.from X :=
t.hom_ext _ _
#align category_theory.limits.is_terminal.comp_from CategoryTheory.Limits.IsTerminal.comp_from
@[simp]
theorem IsTerminal.from_self {X : C} (t : IsTerminal X) : t.from X = 𝟙 X :=
t.hom_ext _ _
#align category_theory.limits.is_terminal.from_self CategoryTheory.Limits.IsTerminal.from_self
def IsInitial.to {X : C} (t : IsInitial X) (Y : C) : X ⟶ Y :=
t.desc (asEmptyCocone Y)
#align category_theory.limits.is_initial.to CategoryTheory.Limits.IsInitial.to
theorem IsInitial.hom_ext {X Y : C} (t : IsInitial X) (f g : X ⟶ Y) : f = g :=
IsColimit.hom_ext t (by aesop_cat)
#align category_theory.limits.is_initial.hom_ext CategoryTheory.Limits.IsInitial.hom_ext
@[simp]
theorem IsInitial.to_comp {X : C} (t : IsInitial X) {Y Z : C} (f : Y ⟶ Z) : t.to Y ≫ f = t.to Z :=
t.hom_ext _ _
#align category_theory.limits.is_initial.to_comp CategoryTheory.Limits.IsInitial.to_comp
@[simp]
theorem IsInitial.to_self {X : C} (t : IsInitial X) : t.to X = 𝟙 X :=
t.hom_ext _ _
#align category_theory.limits.is_initial.to_self CategoryTheory.Limits.IsInitial.to_self
theorem IsTerminal.isSplitMono_from {X Y : C} (t : IsTerminal X) (f : X ⟶ Y) : IsSplitMono f :=
IsSplitMono.mk' ⟨t.from _, t.hom_ext _ _⟩
#align category_theory.limits.is_terminal.is_split_mono_from CategoryTheory.Limits.IsTerminal.isSplitMono_from
theorem IsInitial.isSplitEpi_to {X Y : C} (t : IsInitial X) (f : Y ⟶ X) : IsSplitEpi f :=
IsSplitEpi.mk' ⟨t.to _, t.hom_ext _ _⟩
#align category_theory.limits.is_initial.is_split_epi_to CategoryTheory.Limits.IsInitial.isSplitEpi_to
theorem IsTerminal.mono_from {X Y : C} (t : IsTerminal X) (f : X ⟶ Y) : Mono f := by
haveI := t.isSplitMono_from f; infer_instance
#align category_theory.limits.is_terminal.mono_from CategoryTheory.Limits.IsTerminal.mono_from
| Mathlib/CategoryTheory/Limits/Shapes/Terminal.lean | 213 | 214 | theorem IsInitial.epi_to {X Y : C} (t : IsInitial X) (f : Y ⟶ X) : Epi f := by |
haveI := t.isSplitEpi_to f; infer_instance
|
import Mathlib.MeasureTheory.Measure.NullMeasurable
import Mathlib.MeasureTheory.MeasurableSpace.Basic
import Mathlib.Topology.Algebra.Order.LiminfLimsup
#align_import measure_theory.measure.measure_space from "leanprover-community/mathlib"@"343e80208d29d2d15f8050b929aa50fe4ce71b55"
noncomputable section
open Set
open Filter hiding map
open Function MeasurableSpace
open scoped Classical symmDiff
open Topology Filter ENNReal NNReal Interval MeasureTheory
variable {α β γ δ ι R R' : Type*}
namespace MeasureTheory
section
variable {m : MeasurableSpace α} {μ μ₁ μ₂ : Measure α} {s s₁ s₂ t : Set α}
instance ae_isMeasurablyGenerated : IsMeasurablyGenerated (ae μ) :=
⟨fun _s hs =>
let ⟨t, hst, htm, htμ⟩ := exists_measurable_superset_of_null hs
⟨tᶜ, compl_mem_ae_iff.2 htμ, htm.compl, compl_subset_comm.1 hst⟩⟩
#align measure_theory.ae_is_measurably_generated MeasureTheory.ae_isMeasurablyGenerated
theorem ae_uIoc_iff [LinearOrder α] {a b : α} {P : α → Prop} :
(∀ᵐ x ∂μ, x ∈ Ι a b → P x) ↔ (∀ᵐ x ∂μ, x ∈ Ioc a b → P x) ∧ ∀ᵐ x ∂μ, x ∈ Ioc b a → P x := by
simp only [uIoc_eq_union, mem_union, or_imp, eventually_and]
#align measure_theory.ae_uIoc_iff MeasureTheory.ae_uIoc_iff
theorem measure_union (hd : Disjoint s₁ s₂) (h : MeasurableSet s₂) : μ (s₁ ∪ s₂) = μ s₁ + μ s₂ :=
measure_union₀ h.nullMeasurableSet hd.aedisjoint
#align measure_theory.measure_union MeasureTheory.measure_union
theorem measure_union' (hd : Disjoint s₁ s₂) (h : MeasurableSet s₁) : μ (s₁ ∪ s₂) = μ s₁ + μ s₂ :=
measure_union₀' h.nullMeasurableSet hd.aedisjoint
#align measure_theory.measure_union' MeasureTheory.measure_union'
theorem measure_inter_add_diff (s : Set α) (ht : MeasurableSet t) : μ (s ∩ t) + μ (s \ t) = μ s :=
measure_inter_add_diff₀ _ ht.nullMeasurableSet
#align measure_theory.measure_inter_add_diff MeasureTheory.measure_inter_add_diff
theorem measure_diff_add_inter (s : Set α) (ht : MeasurableSet t) : μ (s \ t) + μ (s ∩ t) = μ s :=
(add_comm _ _).trans (measure_inter_add_diff s ht)
#align measure_theory.measure_diff_add_inter MeasureTheory.measure_diff_add_inter
theorem measure_union_add_inter (s : Set α) (ht : MeasurableSet t) :
μ (s ∪ t) + μ (s ∩ t) = μ s + μ t := by
rw [← measure_inter_add_diff (s ∪ t) ht, Set.union_inter_cancel_right, union_diff_right, ←
measure_inter_add_diff s ht]
ac_rfl
#align measure_theory.measure_union_add_inter MeasureTheory.measure_union_add_inter
theorem measure_union_add_inter' (hs : MeasurableSet s) (t : Set α) :
μ (s ∪ t) + μ (s ∩ t) = μ s + μ t := by
rw [union_comm, inter_comm, measure_union_add_inter t hs, add_comm]
#align measure_theory.measure_union_add_inter' MeasureTheory.measure_union_add_inter'
lemma measure_symmDiff_eq (hs : MeasurableSet s) (ht : MeasurableSet t) :
μ (s ∆ t) = μ (s \ t) + μ (t \ s) := by
simpa only [symmDiff_def, sup_eq_union] using measure_union disjoint_sdiff_sdiff (ht.diff hs)
lemma measure_symmDiff_le (s t u : Set α) :
μ (s ∆ u) ≤ μ (s ∆ t) + μ (t ∆ u) :=
le_trans (μ.mono <| symmDiff_triangle s t u) (measure_union_le (s ∆ t) (t ∆ u))
theorem measure_add_measure_compl (h : MeasurableSet s) : μ s + μ sᶜ = μ univ :=
measure_add_measure_compl₀ h.nullMeasurableSet
#align measure_theory.measure_add_measure_compl MeasureTheory.measure_add_measure_compl
theorem measure_biUnion₀ {s : Set β} {f : β → Set α} (hs : s.Countable)
(hd : s.Pairwise (AEDisjoint μ on f)) (h : ∀ b ∈ s, NullMeasurableSet (f b) μ) :
μ (⋃ b ∈ s, f b) = ∑' p : s, μ (f p) := by
haveI := hs.toEncodable
rw [biUnion_eq_iUnion]
exact measure_iUnion₀ (hd.on_injective Subtype.coe_injective fun x => x.2) fun x => h x x.2
#align measure_theory.measure_bUnion₀ MeasureTheory.measure_biUnion₀
theorem measure_biUnion {s : Set β} {f : β → Set α} (hs : s.Countable) (hd : s.PairwiseDisjoint f)
(h : ∀ b ∈ s, MeasurableSet (f b)) : μ (⋃ b ∈ s, f b) = ∑' p : s, μ (f p) :=
measure_biUnion₀ hs hd.aedisjoint fun b hb => (h b hb).nullMeasurableSet
#align measure_theory.measure_bUnion MeasureTheory.measure_biUnion
theorem measure_sUnion₀ {S : Set (Set α)} (hs : S.Countable) (hd : S.Pairwise (AEDisjoint μ))
(h : ∀ s ∈ S, NullMeasurableSet s μ) : μ (⋃₀ S) = ∑' s : S, μ s := by
rw [sUnion_eq_biUnion, measure_biUnion₀ hs hd h]
#align measure_theory.measure_sUnion₀ MeasureTheory.measure_sUnion₀
theorem measure_sUnion {S : Set (Set α)} (hs : S.Countable) (hd : S.Pairwise Disjoint)
(h : ∀ s ∈ S, MeasurableSet s) : μ (⋃₀ S) = ∑' s : S, μ s := by
rw [sUnion_eq_biUnion, measure_biUnion hs hd h]
#align measure_theory.measure_sUnion MeasureTheory.measure_sUnion
theorem measure_biUnion_finset₀ {s : Finset ι} {f : ι → Set α}
(hd : Set.Pairwise (↑s) (AEDisjoint μ on f)) (hm : ∀ b ∈ s, NullMeasurableSet (f b) μ) :
μ (⋃ b ∈ s, f b) = ∑ p ∈ s, μ (f p) := by
rw [← Finset.sum_attach, Finset.attach_eq_univ, ← tsum_fintype]
exact measure_biUnion₀ s.countable_toSet hd hm
#align measure_theory.measure_bUnion_finset₀ MeasureTheory.measure_biUnion_finset₀
theorem measure_biUnion_finset {s : Finset ι} {f : ι → Set α} (hd : PairwiseDisjoint (↑s) f)
(hm : ∀ b ∈ s, MeasurableSet (f b)) : μ (⋃ b ∈ s, f b) = ∑ p ∈ s, μ (f p) :=
measure_biUnion_finset₀ hd.aedisjoint fun b hb => (hm b hb).nullMeasurableSet
#align measure_theory.measure_bUnion_finset MeasureTheory.measure_biUnion_finset
theorem tsum_meas_le_meas_iUnion_of_disjoint₀ {ι : Type*} [MeasurableSpace α] (μ : Measure α)
{As : ι → Set α} (As_mble : ∀ i : ι, NullMeasurableSet (As i) μ)
(As_disj : Pairwise (AEDisjoint μ on As)) : (∑' i, μ (As i)) ≤ μ (⋃ i, As i) := by
rw [ENNReal.tsum_eq_iSup_sum, iSup_le_iff]
intro s
simp only [← measure_biUnion_finset₀ (fun _i _hi _j _hj hij => As_disj hij) fun i _ => As_mble i]
gcongr
exact iUnion_subset fun _ ↦ Subset.rfl
theorem tsum_meas_le_meas_iUnion_of_disjoint {ι : Type*} [MeasurableSpace α] (μ : Measure α)
{As : ι → Set α} (As_mble : ∀ i : ι, MeasurableSet (As i))
(As_disj : Pairwise (Disjoint on As)) : (∑' i, μ (As i)) ≤ μ (⋃ i, As i) :=
tsum_meas_le_meas_iUnion_of_disjoint₀ μ (fun i ↦ (As_mble i).nullMeasurableSet)
(fun _ _ h ↦ Disjoint.aedisjoint (As_disj h))
#align measure_theory.tsum_meas_le_meas_Union_of_disjoint MeasureTheory.tsum_meas_le_meas_iUnion_of_disjoint
theorem tsum_measure_preimage_singleton {s : Set β} (hs : s.Countable) {f : α → β}
(hf : ∀ y ∈ s, MeasurableSet (f ⁻¹' {y})) : (∑' b : s, μ (f ⁻¹' {↑b})) = μ (f ⁻¹' s) := by
rw [← Set.biUnion_preimage_singleton, measure_biUnion hs (pairwiseDisjoint_fiber f s) hf]
#align measure_theory.tsum_measure_preimage_singleton MeasureTheory.tsum_measure_preimage_singleton
lemma measure_preimage_eq_zero_iff_of_countable {s : Set β} {f : α → β} (hs : s.Countable) :
μ (f ⁻¹' s) = 0 ↔ ∀ x ∈ s, μ (f ⁻¹' {x}) = 0 := by
rw [← biUnion_preimage_singleton, measure_biUnion_null_iff hs]
theorem sum_measure_preimage_singleton (s : Finset β) {f : α → β}
(hf : ∀ y ∈ s, MeasurableSet (f ⁻¹' {y})) : (∑ b ∈ s, μ (f ⁻¹' {b})) = μ (f ⁻¹' ↑s) := by
simp only [← measure_biUnion_finset (pairwiseDisjoint_fiber f s) hf,
Finset.set_biUnion_preimage_singleton]
#align measure_theory.sum_measure_preimage_singleton MeasureTheory.sum_measure_preimage_singleton
theorem measure_diff_null' (h : μ (s₁ ∩ s₂) = 0) : μ (s₁ \ s₂) = μ s₁ :=
measure_congr <| diff_ae_eq_self.2 h
#align measure_theory.measure_diff_null' MeasureTheory.measure_diff_null'
theorem measure_add_diff (hs : MeasurableSet s) (t : Set α) : μ s + μ (t \ s) = μ (s ∪ t) := by
rw [← measure_union' disjoint_sdiff_right hs, union_diff_self]
#align measure_theory.measure_add_diff MeasureTheory.measure_add_diff
theorem measure_diff' (s : Set α) (hm : MeasurableSet t) (h_fin : μ t ≠ ∞) :
μ (s \ t) = μ (s ∪ t) - μ t :=
Eq.symm <| ENNReal.sub_eq_of_add_eq h_fin <| by rw [add_comm, measure_add_diff hm, union_comm]
#align measure_theory.measure_diff' MeasureTheory.measure_diff'
theorem measure_diff (h : s₂ ⊆ s₁) (h₂ : MeasurableSet s₂) (h_fin : μ s₂ ≠ ∞) :
μ (s₁ \ s₂) = μ s₁ - μ s₂ := by rw [measure_diff' _ h₂ h_fin, union_eq_self_of_subset_right h]
#align measure_theory.measure_diff MeasureTheory.measure_diff
theorem le_measure_diff : μ s₁ - μ s₂ ≤ μ (s₁ \ s₂) :=
tsub_le_iff_left.2 <| (measure_le_inter_add_diff μ s₁ s₂).trans <| by
gcongr; apply inter_subset_right
#align measure_theory.le_measure_diff MeasureTheory.le_measure_diff
theorem measure_eq_top_iff_of_symmDiff (hμst : μ (s ∆ t) ≠ ∞) : μ s = ∞ ↔ μ t = ∞ := by
suffices h : ∀ u v, μ (u ∆ v) ≠ ∞ → μ u = ∞ → μ v = ∞
from ⟨h s t hμst, h t s (symmDiff_comm s t ▸ hμst)⟩
intro u v hμuv hμu
by_contra! hμv
apply hμuv
rw [Set.symmDiff_def, eq_top_iff]
calc
∞ = μ u - μ v := (WithTop.sub_eq_top_iff.2 ⟨hμu, hμv⟩).symm
_ ≤ μ (u \ v) := le_measure_diff
_ ≤ μ (u \ v ∪ v \ u) := measure_mono subset_union_left
theorem measure_ne_top_iff_of_symmDiff (hμst : μ (s ∆ t) ≠ ∞) : μ s ≠ ∞ ↔ μ t ≠ ∞ :=
(measure_eq_top_iff_of_symmDiff hμst).ne
theorem measure_diff_lt_of_lt_add (hs : MeasurableSet s) (hst : s ⊆ t) (hs' : μ s ≠ ∞) {ε : ℝ≥0∞}
(h : μ t < μ s + ε) : μ (t \ s) < ε := by
rw [measure_diff hst hs hs']; rw [add_comm] at h
exact ENNReal.sub_lt_of_lt_add (measure_mono hst) h
#align measure_theory.measure_diff_lt_of_lt_add MeasureTheory.measure_diff_lt_of_lt_add
theorem measure_diff_le_iff_le_add (hs : MeasurableSet s) (hst : s ⊆ t) (hs' : μ s ≠ ∞) {ε : ℝ≥0∞} :
μ (t \ s) ≤ ε ↔ μ t ≤ μ s + ε := by rw [measure_diff hst hs hs', tsub_le_iff_left]
#align measure_theory.measure_diff_le_iff_le_add MeasureTheory.measure_diff_le_iff_le_add
theorem measure_eq_measure_of_null_diff {s t : Set α} (hst : s ⊆ t) (h_nulldiff : μ (t \ s) = 0) :
μ s = μ t := measure_congr <|
EventuallyLE.antisymm (HasSubset.Subset.eventuallyLE hst) (ae_le_set.mpr h_nulldiff)
#align measure_theory.measure_eq_measure_of_null_diff MeasureTheory.measure_eq_measure_of_null_diff
theorem measure_eq_measure_of_between_null_diff {s₁ s₂ s₃ : Set α} (h12 : s₁ ⊆ s₂) (h23 : s₂ ⊆ s₃)
(h_nulldiff : μ (s₃ \ s₁) = 0) : μ s₁ = μ s₂ ∧ μ s₂ = μ s₃ := by
have le12 : μ s₁ ≤ μ s₂ := measure_mono h12
have le23 : μ s₂ ≤ μ s₃ := measure_mono h23
have key : μ s₃ ≤ μ s₁ :=
calc
μ s₃ = μ (s₃ \ s₁ ∪ s₁) := by rw [diff_union_of_subset (h12.trans h23)]
_ ≤ μ (s₃ \ s₁) + μ s₁ := measure_union_le _ _
_ = μ s₁ := by simp only [h_nulldiff, zero_add]
exact ⟨le12.antisymm (le23.trans key), le23.antisymm (key.trans le12)⟩
#align measure_theory.measure_eq_measure_of_between_null_diff MeasureTheory.measure_eq_measure_of_between_null_diff
theorem measure_eq_measure_smaller_of_between_null_diff {s₁ s₂ s₃ : Set α} (h12 : s₁ ⊆ s₂)
(h23 : s₂ ⊆ s₃) (h_nulldiff : μ (s₃ \ s₁) = 0) : μ s₁ = μ s₂ :=
(measure_eq_measure_of_between_null_diff h12 h23 h_nulldiff).1
#align measure_theory.measure_eq_measure_smaller_of_between_null_diff MeasureTheory.measure_eq_measure_smaller_of_between_null_diff
theorem measure_eq_measure_larger_of_between_null_diff {s₁ s₂ s₃ : Set α} (h12 : s₁ ⊆ s₂)
(h23 : s₂ ⊆ s₃) (h_nulldiff : μ (s₃ \ s₁) = 0) : μ s₂ = μ s₃ :=
(measure_eq_measure_of_between_null_diff h12 h23 h_nulldiff).2
#align measure_theory.measure_eq_measure_larger_of_between_null_diff MeasureTheory.measure_eq_measure_larger_of_between_null_diff
lemma measure_compl₀ (h : NullMeasurableSet s μ) (hs : μ s ≠ ∞) :
μ sᶜ = μ Set.univ - μ s := by
rw [← measure_add_measure_compl₀ h, ENNReal.add_sub_cancel_left hs]
theorem measure_compl (h₁ : MeasurableSet s) (h_fin : μ s ≠ ∞) : μ sᶜ = μ univ - μ s :=
measure_compl₀ h₁.nullMeasurableSet h_fin
#align measure_theory.measure_compl MeasureTheory.measure_compl
lemma measure_inter_conull' (ht : μ (s \ t) = 0) : μ (s ∩ t) = μ s := by
rw [← diff_compl, measure_diff_null']; rwa [← diff_eq]
lemma measure_inter_conull (ht : μ tᶜ = 0) : μ (s ∩ t) = μ s := by
rw [← diff_compl, measure_diff_null ht]
@[simp]
theorem union_ae_eq_left_iff_ae_subset : (s ∪ t : Set α) =ᵐ[μ] s ↔ t ≤ᵐ[μ] s := by
rw [ae_le_set]
refine
⟨fun h => by simpa only [union_diff_left] using (ae_eq_set.mp h).1, fun h =>
eventuallyLE_antisymm_iff.mpr
⟨by rwa [ae_le_set, union_diff_left],
HasSubset.Subset.eventuallyLE subset_union_left⟩⟩
#align measure_theory.union_ae_eq_left_iff_ae_subset MeasureTheory.union_ae_eq_left_iff_ae_subset
@[simp]
theorem union_ae_eq_right_iff_ae_subset : (s ∪ t : Set α) =ᵐ[μ] t ↔ s ≤ᵐ[μ] t := by
rw [union_comm, union_ae_eq_left_iff_ae_subset]
#align measure_theory.union_ae_eq_right_iff_ae_subset MeasureTheory.union_ae_eq_right_iff_ae_subset
theorem ae_eq_of_ae_subset_of_measure_ge (h₁ : s ≤ᵐ[μ] t) (h₂ : μ t ≤ μ s) (hsm : MeasurableSet s)
(ht : μ t ≠ ∞) : s =ᵐ[μ] t := by
refine eventuallyLE_antisymm_iff.mpr ⟨h₁, ae_le_set.mpr ?_⟩
replace h₂ : μ t = μ s := h₂.antisymm (measure_mono_ae h₁)
replace ht : μ s ≠ ∞ := h₂ ▸ ht
rw [measure_diff' t hsm ht, measure_congr (union_ae_eq_left_iff_ae_subset.mpr h₁), h₂, tsub_self]
#align measure_theory.ae_eq_of_ae_subset_of_measure_ge MeasureTheory.ae_eq_of_ae_subset_of_measure_ge
theorem ae_eq_of_subset_of_measure_ge (h₁ : s ⊆ t) (h₂ : μ t ≤ μ s) (hsm : MeasurableSet s)
(ht : μ t ≠ ∞) : s =ᵐ[μ] t :=
ae_eq_of_ae_subset_of_measure_ge (HasSubset.Subset.eventuallyLE h₁) h₂ hsm ht
#align measure_theory.ae_eq_of_subset_of_measure_ge MeasureTheory.ae_eq_of_subset_of_measure_ge
theorem measure_iUnion_congr_of_subset [Countable β] {s : β → Set α} {t : β → Set α}
(hsub : ∀ b, s b ⊆ t b) (h_le : ∀ b, μ (t b) ≤ μ (s b)) : μ (⋃ b, s b) = μ (⋃ b, t b) := by
rcases Classical.em (∃ b, μ (t b) = ∞) with (⟨b, hb⟩ | htop)
· calc
μ (⋃ b, s b) = ∞ := top_unique (hb ▸ (h_le b).trans <| measure_mono <| subset_iUnion _ _)
_ = μ (⋃ b, t b) := Eq.symm <| top_unique <| hb ▸ measure_mono (subset_iUnion _ _)
push_neg at htop
refine le_antisymm (measure_mono (iUnion_mono hsub)) ?_
set M := toMeasurable μ
have H : ∀ b, (M (t b) ∩ M (⋃ b, s b) : Set α) =ᵐ[μ] M (t b) := by
refine fun b => ae_eq_of_subset_of_measure_ge inter_subset_left ?_ ?_ ?_
· calc
μ (M (t b)) = μ (t b) := measure_toMeasurable _
_ ≤ μ (s b) := h_le b
_ ≤ μ (M (t b) ∩ M (⋃ b, s b)) :=
measure_mono <|
subset_inter ((hsub b).trans <| subset_toMeasurable _ _)
((subset_iUnion _ _).trans <| subset_toMeasurable _ _)
· exact (measurableSet_toMeasurable _ _).inter (measurableSet_toMeasurable _ _)
· rw [measure_toMeasurable]
exact htop b
calc
μ (⋃ b, t b) ≤ μ (⋃ b, M (t b)) := measure_mono (iUnion_mono fun b => subset_toMeasurable _ _)
_ = μ (⋃ b, M (t b) ∩ M (⋃ b, s b)) := measure_congr (EventuallyEq.countable_iUnion H).symm
_ ≤ μ (M (⋃ b, s b)) := measure_mono (iUnion_subset fun b => inter_subset_right)
_ = μ (⋃ b, s b) := measure_toMeasurable _
#align measure_theory.measure_Union_congr_of_subset MeasureTheory.measure_iUnion_congr_of_subset
theorem measure_union_congr_of_subset {t₁ t₂ : Set α} (hs : s₁ ⊆ s₂) (hsμ : μ s₂ ≤ μ s₁)
(ht : t₁ ⊆ t₂) (htμ : μ t₂ ≤ μ t₁) : μ (s₁ ∪ t₁) = μ (s₂ ∪ t₂) := by
rw [union_eq_iUnion, union_eq_iUnion]
exact measure_iUnion_congr_of_subset (Bool.forall_bool.2 ⟨ht, hs⟩) (Bool.forall_bool.2 ⟨htμ, hsμ⟩)
#align measure_theory.measure_union_congr_of_subset MeasureTheory.measure_union_congr_of_subset
@[simp]
theorem measure_iUnion_toMeasurable [Countable β] (s : β → Set α) :
μ (⋃ b, toMeasurable μ (s b)) = μ (⋃ b, s b) :=
Eq.symm <|
measure_iUnion_congr_of_subset (fun _b => subset_toMeasurable _ _) fun _b =>
(measure_toMeasurable _).le
#align measure_theory.measure_Union_to_measurable MeasureTheory.measure_iUnion_toMeasurable
theorem measure_biUnion_toMeasurable {I : Set β} (hc : I.Countable) (s : β → Set α) :
μ (⋃ b ∈ I, toMeasurable μ (s b)) = μ (⋃ b ∈ I, s b) := by
haveI := hc.toEncodable
simp only [biUnion_eq_iUnion, measure_iUnion_toMeasurable]
#align measure_theory.measure_bUnion_to_measurable MeasureTheory.measure_biUnion_toMeasurable
@[simp]
theorem measure_toMeasurable_union : μ (toMeasurable μ s ∪ t) = μ (s ∪ t) :=
Eq.symm <|
measure_union_congr_of_subset (subset_toMeasurable _ _) (measure_toMeasurable _).le Subset.rfl
le_rfl
#align measure_theory.measure_to_measurable_union MeasureTheory.measure_toMeasurable_union
@[simp]
theorem measure_union_toMeasurable : μ (s ∪ toMeasurable μ t) = μ (s ∪ t) :=
Eq.symm <|
measure_union_congr_of_subset Subset.rfl le_rfl (subset_toMeasurable _ _)
(measure_toMeasurable _).le
#align measure_theory.measure_union_to_measurable MeasureTheory.measure_union_toMeasurable
theorem sum_measure_le_measure_univ {s : Finset ι} {t : ι → Set α}
(h : ∀ i ∈ s, MeasurableSet (t i)) (H : Set.PairwiseDisjoint (↑s) t) :
(∑ i ∈ s, μ (t i)) ≤ μ (univ : Set α) := by
rw [← measure_biUnion_finset H h]
exact measure_mono (subset_univ _)
#align measure_theory.sum_measure_le_measure_univ MeasureTheory.sum_measure_le_measure_univ
theorem tsum_measure_le_measure_univ {s : ι → Set α} (hs : ∀ i, MeasurableSet (s i))
(H : Pairwise (Disjoint on s)) : (∑' i, μ (s i)) ≤ μ (univ : Set α) := by
rw [ENNReal.tsum_eq_iSup_sum]
exact iSup_le fun s =>
sum_measure_le_measure_univ (fun i _hi => hs i) fun i _hi j _hj hij => H hij
#align measure_theory.tsum_measure_le_measure_univ MeasureTheory.tsum_measure_le_measure_univ
theorem exists_nonempty_inter_of_measure_univ_lt_tsum_measure {m : MeasurableSpace α}
(μ : Measure α) {s : ι → Set α} (hs : ∀ i, MeasurableSet (s i))
(H : μ (univ : Set α) < ∑' i, μ (s i)) : ∃ i j, i ≠ j ∧ (s i ∩ s j).Nonempty := by
contrapose! H
apply tsum_measure_le_measure_univ hs
intro i j hij
exact disjoint_iff_inter_eq_empty.mpr (H i j hij)
#align measure_theory.exists_nonempty_inter_of_measure_univ_lt_tsum_measure MeasureTheory.exists_nonempty_inter_of_measure_univ_lt_tsum_measure
theorem exists_nonempty_inter_of_measure_univ_lt_sum_measure {m : MeasurableSpace α} (μ : Measure α)
{s : Finset ι} {t : ι → Set α} (h : ∀ i ∈ s, MeasurableSet (t i))
(H : μ (univ : Set α) < ∑ i ∈ s, μ (t i)) :
∃ i ∈ s, ∃ j ∈ s, ∃ _h : i ≠ j, (t i ∩ t j).Nonempty := by
contrapose! H
apply sum_measure_le_measure_univ h
intro i hi j hj hij
exact disjoint_iff_inter_eq_empty.mpr (H i hi j hj hij)
#align measure_theory.exists_nonempty_inter_of_measure_univ_lt_sum_measure MeasureTheory.exists_nonempty_inter_of_measure_univ_lt_sum_measure
theorem nonempty_inter_of_measure_lt_add {m : MeasurableSpace α} (μ : Measure α) {s t u : Set α}
(ht : MeasurableSet t) (h's : s ⊆ u) (h't : t ⊆ u) (h : μ u < μ s + μ t) :
(s ∩ t).Nonempty := by
rw [← Set.not_disjoint_iff_nonempty_inter]
contrapose! h
calc
μ s + μ t = μ (s ∪ t) := (measure_union h ht).symm
_ ≤ μ u := measure_mono (union_subset h's h't)
#align measure_theory.nonempty_inter_of_measure_lt_add MeasureTheory.nonempty_inter_of_measure_lt_add
theorem nonempty_inter_of_measure_lt_add' {m : MeasurableSpace α} (μ : Measure α) {s t u : Set α}
(hs : MeasurableSet s) (h's : s ⊆ u) (h't : t ⊆ u) (h : μ u < μ s + μ t) :
(s ∩ t).Nonempty := by
rw [add_comm] at h
rw [inter_comm]
exact nonempty_inter_of_measure_lt_add μ hs h't h's h
#align measure_theory.nonempty_inter_of_measure_lt_add' MeasureTheory.nonempty_inter_of_measure_lt_add'
theorem measure_iUnion_eq_iSup [Countable ι] {s : ι → Set α} (hd : Directed (· ⊆ ·) s) :
μ (⋃ i, s i) = ⨆ i, μ (s i) := by
cases nonempty_encodable ι
-- WLOG, `ι = ℕ`
generalize ht : Function.extend Encodable.encode s ⊥ = t
replace hd : Directed (· ⊆ ·) t := ht ▸ hd.extend_bot Encodable.encode_injective
suffices μ (⋃ n, t n) = ⨆ n, μ (t n) by
simp only [← ht, Function.apply_extend μ, ← iSup_eq_iUnion,
iSup_extend_bot Encodable.encode_injective, (· ∘ ·), Pi.bot_apply, bot_eq_empty,
measure_empty] at this
exact this.trans (iSup_extend_bot Encodable.encode_injective _)
clear! ι
-- The `≥` inequality is trivial
refine le_antisymm ?_ (iSup_le fun i => measure_mono <| subset_iUnion _ _)
-- Choose `T n ⊇ t n` of the same measure, put `Td n = disjointed T`
set T : ℕ → Set α := fun n => toMeasurable μ (t n)
set Td : ℕ → Set α := disjointed T
have hm : ∀ n, MeasurableSet (Td n) :=
MeasurableSet.disjointed fun n => measurableSet_toMeasurable _ _
calc
μ (⋃ n, t n) ≤ μ (⋃ n, T n) := measure_mono (iUnion_mono fun i => subset_toMeasurable _ _)
_ = μ (⋃ n, Td n) := by rw [iUnion_disjointed]
_ ≤ ∑' n, μ (Td n) := measure_iUnion_le _
_ = ⨆ I : Finset ℕ, ∑ n ∈ I, μ (Td n) := ENNReal.tsum_eq_iSup_sum
_ ≤ ⨆ n, μ (t n) := iSup_le fun I => by
rcases hd.finset_le I with ⟨N, hN⟩
calc
(∑ n ∈ I, μ (Td n)) = μ (⋃ n ∈ I, Td n) :=
(measure_biUnion_finset ((disjoint_disjointed T).set_pairwise I) fun n _ => hm n).symm
_ ≤ μ (⋃ n ∈ I, T n) := measure_mono (iUnion₂_mono fun n _hn => disjointed_subset _ _)
_ = μ (⋃ n ∈ I, t n) := measure_biUnion_toMeasurable I.countable_toSet _
_ ≤ μ (t N) := measure_mono (iUnion₂_subset hN)
_ ≤ ⨆ n, μ (t n) := le_iSup (μ ∘ t) N
#align measure_theory.measure_Union_eq_supr MeasureTheory.measure_iUnion_eq_iSup
theorem measure_iUnion_eq_iSup' {α ι : Type*} [MeasurableSpace α] {μ : Measure α}
[Countable ι] [Preorder ι] [IsDirected ι (· ≤ ·)]
{f : ι → Set α} : μ (⋃ i, f i) = ⨆ i, μ (Accumulate f i) := by
have hd : Directed (· ⊆ ·) (Accumulate f) := by
intro i j
rcases directed_of (· ≤ ·) i j with ⟨k, rik, rjk⟩
exact ⟨k, biUnion_subset_biUnion_left fun l rli ↦ le_trans rli rik,
biUnion_subset_biUnion_left fun l rlj ↦ le_trans rlj rjk⟩
rw [← iUnion_accumulate]
exact measure_iUnion_eq_iSup hd
theorem measure_biUnion_eq_iSup {s : ι → Set α} {t : Set ι} (ht : t.Countable)
(hd : DirectedOn ((· ⊆ ·) on s) t) : μ (⋃ i ∈ t, s i) = ⨆ i ∈ t, μ (s i) := by
haveI := ht.toEncodable
rw [biUnion_eq_iUnion, measure_iUnion_eq_iSup hd.directed_val, ← iSup_subtype'']
#align measure_theory.measure_bUnion_eq_supr MeasureTheory.measure_biUnion_eq_iSup
theorem measure_iInter_eq_iInf [Countable ι] {s : ι → Set α} (h : ∀ i, MeasurableSet (s i))
(hd : Directed (· ⊇ ·) s) (hfin : ∃ i, μ (s i) ≠ ∞) : μ (⋂ i, s i) = ⨅ i, μ (s i) := by
rcases hfin with ⟨k, hk⟩
have : ∀ t ⊆ s k, μ t ≠ ∞ := fun t ht => ne_top_of_le_ne_top hk (measure_mono ht)
rw [← ENNReal.sub_sub_cancel hk (iInf_le _ k), ENNReal.sub_iInf, ←
ENNReal.sub_sub_cancel hk (measure_mono (iInter_subset _ k)), ←
measure_diff (iInter_subset _ k) (MeasurableSet.iInter h) (this _ (iInter_subset _ k)),
diff_iInter, measure_iUnion_eq_iSup]
· congr 1
refine le_antisymm (iSup_mono' fun i => ?_) (iSup_mono fun i => ?_)
· rcases hd i k with ⟨j, hji, hjk⟩
use j
rw [← measure_diff hjk (h _) (this _ hjk)]
gcongr
· rw [tsub_le_iff_right, ← measure_union, Set.union_comm]
· exact measure_mono (diff_subset_iff.1 Subset.rfl)
· apply disjoint_sdiff_left
· apply h i
· exact hd.mono_comp _ fun _ _ => diff_subset_diff_right
#align measure_theory.measure_Inter_eq_infi MeasureTheory.measure_iInter_eq_iInf
theorem measure_iInter_eq_iInf' {α ι : Type*} [MeasurableSpace α] {μ : Measure α}
[Countable ι] [Preorder ι] [IsDirected ι (· ≤ ·)]
{f : ι → Set α} (h : ∀ i, MeasurableSet (f i)) (hfin : ∃ i, μ (f i) ≠ ∞) :
μ (⋂ i, f i) = ⨅ i, μ (⋂ j ≤ i, f j) := by
let s := fun i ↦ ⋂ j ≤ i, f j
have iInter_eq : ⋂ i, f i = ⋂ i, s i := by
ext x; simp [s]; constructor
· exact fun h _ j _ ↦ h j
· intro h i
rcases directed_of (· ≤ ·) i i with ⟨j, rij, -⟩
exact h j i rij
have ms : ∀ i, MeasurableSet (s i) :=
fun i ↦ MeasurableSet.biInter (countable_univ.mono <| subset_univ _) fun i _ ↦ h i
have hd : Directed (· ⊇ ·) s := by
intro i j
rcases directed_of (· ≤ ·) i j with ⟨k, rik, rjk⟩
exact ⟨k, biInter_subset_biInter_left fun j rji ↦ le_trans rji rik,
biInter_subset_biInter_left fun i rij ↦ le_trans rij rjk⟩
have hfin' : ∃ i, μ (s i) ≠ ∞ := by
rcases hfin with ⟨i, hi⟩
rcases directed_of (· ≤ ·) i i with ⟨j, rij, -⟩
exact ⟨j, ne_top_of_le_ne_top hi <| measure_mono <| biInter_subset_of_mem rij⟩
exact iInter_eq ▸ measure_iInter_eq_iInf ms hd hfin'
theorem tendsto_measure_iUnion [Preorder ι] [IsDirected ι (· ≤ ·)] [Countable ι]
{s : ι → Set α} (hm : Monotone s) : Tendsto (μ ∘ s) atTop (𝓝 (μ (⋃ n, s n))) := by
rw [measure_iUnion_eq_iSup hm.directed_le]
exact tendsto_atTop_iSup fun n m hnm => measure_mono <| hm hnm
#align measure_theory.tendsto_measure_Union MeasureTheory.tendsto_measure_iUnion
theorem tendsto_measure_iUnion' {α ι : Type*} [MeasurableSpace α] {μ : Measure α} [Countable ι]
[Preorder ι] [IsDirected ι (· ≤ ·)] {f : ι → Set α} :
Tendsto (fun i ↦ μ (Accumulate f i)) atTop (𝓝 (μ (⋃ i, f i))) := by
rw [measure_iUnion_eq_iSup']
exact tendsto_atTop_iSup fun i j hij ↦ by gcongr
theorem tendsto_measure_iInter [Countable ι] [Preorder ι] [IsDirected ι (· ≤ ·)] {s : ι → Set α}
(hs : ∀ n, MeasurableSet (s n)) (hm : Antitone s) (hf : ∃ i, μ (s i) ≠ ∞) :
Tendsto (μ ∘ s) atTop (𝓝 (μ (⋂ n, s n))) := by
rw [measure_iInter_eq_iInf hs hm.directed_ge hf]
exact tendsto_atTop_iInf fun n m hnm => measure_mono <| hm hnm
#align measure_theory.tendsto_measure_Inter MeasureTheory.tendsto_measure_iInter
theorem tendsto_measure_iInter' {α ι : Type*} [MeasurableSpace α] {μ : Measure α} [Countable ι]
[Preorder ι] [IsDirected ι (· ≤ ·)] {f : ι → Set α} (hm : ∀ i, MeasurableSet (f i))
(hf : ∃ i, μ (f i) ≠ ∞) :
Tendsto (fun i ↦ μ (⋂ j ∈ {j | j ≤ i}, f j)) atTop (𝓝 (μ (⋂ i, f i))) := by
rw [measure_iInter_eq_iInf' hm hf]
exact tendsto_atTop_iInf
fun i j hij ↦ measure_mono <| biInter_subset_biInter_left fun k hki ↦ le_trans hki hij
theorem tendsto_measure_biInter_gt {ι : Type*} [LinearOrder ι] [TopologicalSpace ι]
[OrderTopology ι] [DenselyOrdered ι] [FirstCountableTopology ι] {s : ι → Set α}
{a : ι} (hs : ∀ r > a, MeasurableSet (s r)) (hm : ∀ i j, a < i → i ≤ j → s i ⊆ s j)
(hf : ∃ r > a, μ (s r) ≠ ∞) : Tendsto (μ ∘ s) (𝓝[Ioi a] a) (𝓝 (μ (⋂ r > a, s r))) := by
refine tendsto_order.2 ⟨fun l hl => ?_, fun L hL => ?_⟩
· filter_upwards [self_mem_nhdsWithin (s := Ioi a)] with r hr using hl.trans_le
(measure_mono (biInter_subset_of_mem hr))
obtain ⟨u, u_anti, u_pos, u_lim⟩ :
∃ u : ℕ → ι, StrictAnti u ∧ (∀ n : ℕ, a < u n) ∧ Tendsto u atTop (𝓝 a) := by
rcases hf with ⟨r, ar, _⟩
rcases exists_seq_strictAnti_tendsto' ar with ⟨w, w_anti, w_mem, w_lim⟩
exact ⟨w, w_anti, fun n => (w_mem n).1, w_lim⟩
have A : Tendsto (μ ∘ s ∘ u) atTop (𝓝 (μ (⋂ n, s (u n)))) := by
refine tendsto_measure_iInter (fun n => hs _ (u_pos n)) ?_ ?_
· intro m n hmn
exact hm _ _ (u_pos n) (u_anti.antitone hmn)
· rcases hf with ⟨r, rpos, hr⟩
obtain ⟨n, hn⟩ : ∃ n : ℕ, u n < r := ((tendsto_order.1 u_lim).2 r rpos).exists
refine ⟨n, ne_of_lt (lt_of_le_of_lt ?_ hr.lt_top)⟩
exact measure_mono (hm _ _ (u_pos n) hn.le)
have B : ⋂ n, s (u n) = ⋂ r > a, s r := by
apply Subset.antisymm
· simp only [subset_iInter_iff, gt_iff_lt]
intro r rpos
obtain ⟨n, hn⟩ : ∃ n, u n < r := ((tendsto_order.1 u_lim).2 _ rpos).exists
exact Subset.trans (iInter_subset _ n) (hm (u n) r (u_pos n) hn.le)
· simp only [subset_iInter_iff, gt_iff_lt]
intro n
apply biInter_subset_of_mem
exact u_pos n
rw [B] at A
obtain ⟨n, hn⟩ : ∃ n, μ (s (u n)) < L := ((tendsto_order.1 A).2 _ hL).exists
have : Ioc a (u n) ∈ 𝓝[>] a := Ioc_mem_nhdsWithin_Ioi ⟨le_rfl, u_pos n⟩
filter_upwards [this] with r hr using lt_of_le_of_lt (measure_mono (hm _ _ hr.1 hr.2)) hn
#align measure_theory.tendsto_measure_bInter_gt MeasureTheory.tendsto_measure_biInter_gt
theorem measure_limsup_eq_zero {s : ℕ → Set α} (hs : (∑' i, μ (s i)) ≠ ∞) :
μ (limsup s atTop) = 0 := by
-- First we replace the sequence `sₙ` with a sequence of measurable sets `tₙ ⊇ sₙ` of the same
-- measure.
set t : ℕ → Set α := fun n => toMeasurable μ (s n)
have ht : (∑' i, μ (t i)) ≠ ∞ := by simpa only [t, measure_toMeasurable] using hs
suffices μ (limsup t atTop) = 0 by
have A : s ≤ t := fun n => subset_toMeasurable μ (s n)
-- TODO default args fail
exact measure_mono_null (limsup_le_limsup (eventually_of_forall (Pi.le_def.mp A))) this
-- Next we unfold `limsup` for sets and replace equality with an inequality
simp only [limsup_eq_iInf_iSup_of_nat', Set.iInf_eq_iInter, Set.iSup_eq_iUnion, ←
nonpos_iff_eq_zero]
-- Finally, we estimate `μ (⋃ i, t (i + n))` by `∑ i', μ (t (i + n))`
refine
le_of_tendsto_of_tendsto'
(tendsto_measure_iInter
(fun i => MeasurableSet.iUnion fun b => measurableSet_toMeasurable _ _) ?_
⟨0, ne_top_of_le_ne_top ht (measure_iUnion_le t)⟩)
(ENNReal.tendsto_sum_nat_add (μ ∘ t) ht) fun n => measure_iUnion_le _
intro n m hnm x
simp only [Set.mem_iUnion]
exact fun ⟨i, hi⟩ => ⟨i + (m - n), by simpa only [add_assoc, tsub_add_cancel_of_le hnm] using hi⟩
#align measure_theory.measure_limsup_eq_zero MeasureTheory.measure_limsup_eq_zero
| Mathlib/MeasureTheory/Measure/MeasureSpace.lean | 677 | 681 | theorem measure_liminf_eq_zero {s : ℕ → Set α} (h : (∑' i, μ (s i)) ≠ ∞) :
μ (liminf s atTop) = 0 := by |
rw [← le_zero_iff]
have : liminf s atTop ≤ limsup s atTop := liminf_le_limsup
exact (μ.mono this).trans (by simp [measure_limsup_eq_zero h])
|
import Mathlib.Analysis.Calculus.Deriv.AffineMap
import Mathlib.Analysis.Calculus.Deriv.Slope
import Mathlib.Analysis.Calculus.Deriv.Mul
import Mathlib.Analysis.Calculus.Deriv.Comp
import Mathlib.Analysis.Calculus.LocalExtr.Rolle
import Mathlib.Analysis.Convex.Normed
import Mathlib.Analysis.RCLike.Basic
#align_import analysis.calculus.mean_value from "leanprover-community/mathlib"@"3bce8d800a6f2b8f63fe1e588fd76a9ff4adcebe"
variable {E : Type*} [NormedAddCommGroup E] [NormedSpace ℝ E] {F : Type*} [NormedAddCommGroup F]
[NormedSpace ℝ F]
open Metric Set Asymptotics ContinuousLinearMap Filter
open scoped Classical Topology NNReal
theorem image_le_of_liminf_slope_right_lt_deriv_boundary' {f f' : ℝ → ℝ} {a b : ℝ}
(hf : ContinuousOn f (Icc a b))
-- `hf'` actually says `liminf (f z - f x) / (z - x) ≤ f' x`
(hf' : ∀ x ∈ Ico a b, ∀ r, f' x < r → ∃ᶠ z in 𝓝[>] x, slope f x z < r)
{B B' : ℝ → ℝ} (ha : f a ≤ B a) (hB : ContinuousOn B (Icc a b))
(hB' : ∀ x ∈ Ico a b, HasDerivWithinAt B (B' x) (Ici x) x)
(bound : ∀ x ∈ Ico a b, f x = B x → f' x < B' x) : ∀ ⦃x⦄, x ∈ Icc a b → f x ≤ B x := by
change Icc a b ⊆ { x | f x ≤ B x }
set s := { x | f x ≤ B x } ∩ Icc a b
have A : ContinuousOn (fun x => (f x, B x)) (Icc a b) := hf.prod hB
have : IsClosed s := by
simp only [s, inter_comm]
exact A.preimage_isClosed_of_isClosed isClosed_Icc OrderClosedTopology.isClosed_le'
apply this.Icc_subset_of_forall_exists_gt ha
rintro x ⟨hxB : f x ≤ B x, xab⟩ y hy
cases' hxB.lt_or_eq with hxB hxB
· -- If `f x < B x`, then all we need is continuity of both sides
refine nonempty_of_mem (inter_mem ?_ (Ioc_mem_nhdsWithin_Ioi ⟨le_rfl, hy⟩))
have : ∀ᶠ x in 𝓝[Icc a b] x, f x < B x :=
A x (Ico_subset_Icc_self xab) (IsOpen.mem_nhds (isOpen_lt continuous_fst continuous_snd) hxB)
have : ∀ᶠ x in 𝓝[>] x, f x < B x := nhdsWithin_le_of_mem (Icc_mem_nhdsWithin_Ioi xab) this
exact this.mono fun y => le_of_lt
· rcases exists_between (bound x xab hxB) with ⟨r, hfr, hrB⟩
specialize hf' x xab r hfr
have HB : ∀ᶠ z in 𝓝[>] x, r < slope B x z :=
(hasDerivWithinAt_iff_tendsto_slope' <| lt_irrefl x).1 (hB' x xab).Ioi_of_Ici
(Ioi_mem_nhds hrB)
obtain ⟨z, hfz, hzB, hz⟩ : ∃ z, slope f x z < r ∧ r < slope B x z ∧ z ∈ Ioc x y :=
(hf'.and_eventually (HB.and (Ioc_mem_nhdsWithin_Ioi ⟨le_rfl, hy⟩))).exists
refine ⟨z, ?_, hz⟩
have := (hfz.trans hzB).le
rwa [slope_def_field, slope_def_field, div_le_div_right (sub_pos.2 hz.1), hxB,
sub_le_sub_iff_right] at this
#align image_le_of_liminf_slope_right_lt_deriv_boundary' image_le_of_liminf_slope_right_lt_deriv_boundary'
theorem image_le_of_liminf_slope_right_lt_deriv_boundary {f f' : ℝ → ℝ} {a b : ℝ}
(hf : ContinuousOn f (Icc a b))
-- `hf'` actually says `liminf (f z - f x) / (z - x) ≤ f' x`
(hf' : ∀ x ∈ Ico a b, ∀ r, f' x < r → ∃ᶠ z in 𝓝[>] x, slope f x z < r)
{B B' : ℝ → ℝ} (ha : f a ≤ B a) (hB : ∀ x, HasDerivAt B (B' x) x)
(bound : ∀ x ∈ Ico a b, f x = B x → f' x < B' x) : ∀ ⦃x⦄, x ∈ Icc a b → f x ≤ B x :=
image_le_of_liminf_slope_right_lt_deriv_boundary' hf hf' ha
(fun x _ => (hB x).continuousAt.continuousWithinAt) (fun x _ => (hB x).hasDerivWithinAt) bound
#align image_le_of_liminf_slope_right_lt_deriv_boundary image_le_of_liminf_slope_right_lt_deriv_boundary
theorem image_le_of_liminf_slope_right_le_deriv_boundary {f : ℝ → ℝ} {a b : ℝ}
(hf : ContinuousOn f (Icc a b)) {B B' : ℝ → ℝ} (ha : f a ≤ B a) (hB : ContinuousOn B (Icc a b))
(hB' : ∀ x ∈ Ico a b, HasDerivWithinAt B (B' x) (Ici x) x)
-- `bound` actually says `liminf (f z - f x) / (z - x) ≤ B' x`
(bound : ∀ x ∈ Ico a b, ∀ r, B' x < r → ∃ᶠ z in 𝓝[>] x, slope f x z < r) :
∀ ⦃x⦄, x ∈ Icc a b → f x ≤ B x := by
have Hr : ∀ x ∈ Icc a b, ∀ r > 0, f x ≤ B x + r * (x - a) := fun x hx r hr => by
apply image_le_of_liminf_slope_right_lt_deriv_boundary' hf bound
· rwa [sub_self, mul_zero, add_zero]
· exact hB.add (continuousOn_const.mul (continuousOn_id.sub continuousOn_const))
· intro x hx
exact (hB' x hx).add (((hasDerivWithinAt_id x (Ici x)).sub_const a).const_mul r)
· intro x _ _
rw [mul_one]
exact (lt_add_iff_pos_right _).2 hr
exact hx
intro x hx
have : ContinuousWithinAt (fun r => B x + r * (x - a)) (Ioi 0) 0 :=
continuousWithinAt_const.add (continuousWithinAt_id.mul continuousWithinAt_const)
convert continuousWithinAt_const.closure_le _ this (Hr x hx) using 1 <;> simp
#align image_le_of_liminf_slope_right_le_deriv_boundary image_le_of_liminf_slope_right_le_deriv_boundary
theorem image_le_of_deriv_right_lt_deriv_boundary' {f f' : ℝ → ℝ} {a b : ℝ}
(hf : ContinuousOn f (Icc a b)) (hf' : ∀ x ∈ Ico a b, HasDerivWithinAt f (f' x) (Ici x) x)
{B B' : ℝ → ℝ} (ha : f a ≤ B a) (hB : ContinuousOn B (Icc a b))
(hB' : ∀ x ∈ Ico a b, HasDerivWithinAt B (B' x) (Ici x) x)
(bound : ∀ x ∈ Ico a b, f x = B x → f' x < B' x) : ∀ ⦃x⦄, x ∈ Icc a b → f x ≤ B x :=
image_le_of_liminf_slope_right_lt_deriv_boundary' hf
(fun x hx _ hr => (hf' x hx).liminf_right_slope_le hr) ha hB hB' bound
#align image_le_of_deriv_right_lt_deriv_boundary' image_le_of_deriv_right_lt_deriv_boundary'
theorem image_le_of_deriv_right_lt_deriv_boundary {f f' : ℝ → ℝ} {a b : ℝ}
(hf : ContinuousOn f (Icc a b)) (hf' : ∀ x ∈ Ico a b, HasDerivWithinAt f (f' x) (Ici x) x)
{B B' : ℝ → ℝ} (ha : f a ≤ B a) (hB : ∀ x, HasDerivAt B (B' x) x)
(bound : ∀ x ∈ Ico a b, f x = B x → f' x < B' x) : ∀ ⦃x⦄, x ∈ Icc a b → f x ≤ B x :=
image_le_of_deriv_right_lt_deriv_boundary' hf hf' ha
(fun x _ => (hB x).continuousAt.continuousWithinAt) (fun x _ => (hB x).hasDerivWithinAt) bound
#align image_le_of_deriv_right_lt_deriv_boundary image_le_of_deriv_right_lt_deriv_boundary
theorem image_le_of_deriv_right_le_deriv_boundary {f f' : ℝ → ℝ} {a b : ℝ}
(hf : ContinuousOn f (Icc a b)) (hf' : ∀ x ∈ Ico a b, HasDerivWithinAt f (f' x) (Ici x) x)
{B B' : ℝ → ℝ} (ha : f a ≤ B a) (hB : ContinuousOn B (Icc a b))
(hB' : ∀ x ∈ Ico a b, HasDerivWithinAt B (B' x) (Ici x) x)
(bound : ∀ x ∈ Ico a b, f' x ≤ B' x) : ∀ ⦃x⦄, x ∈ Icc a b → f x ≤ B x :=
image_le_of_liminf_slope_right_le_deriv_boundary hf ha hB hB' fun x hx _ hr =>
(hf' x hx).liminf_right_slope_le (lt_of_le_of_lt (bound x hx) hr)
#align image_le_of_deriv_right_le_deriv_boundary image_le_of_deriv_right_le_deriv_boundary
section
variable {f : ℝ → E} {a b : ℝ}
theorem image_norm_le_of_liminf_right_slope_norm_lt_deriv_boundary {E : Type*}
[NormedAddCommGroup E] {f : ℝ → E} {f' : ℝ → ℝ} (hf : ContinuousOn f (Icc a b))
-- `hf'` actually says `liminf (‖f z‖ - ‖f x‖) / (z - x) ≤ f' x`
(hf' : ∀ x ∈ Ico a b, ∀ r, f' x < r → ∃ᶠ z in 𝓝[>] x, slope (norm ∘ f) x z < r)
{B B' : ℝ → ℝ} (ha : ‖f a‖ ≤ B a) (hB : ContinuousOn B (Icc a b))
(hB' : ∀ x ∈ Ico a b, HasDerivWithinAt B (B' x) (Ici x) x)
(bound : ∀ x ∈ Ico a b, ‖f x‖ = B x → f' x < B' x) : ∀ ⦃x⦄, x ∈ Icc a b → ‖f x‖ ≤ B x :=
image_le_of_liminf_slope_right_lt_deriv_boundary' (continuous_norm.comp_continuousOn hf) hf' ha hB
hB' bound
#align image_norm_le_of_liminf_right_slope_norm_lt_deriv_boundary image_norm_le_of_liminf_right_slope_norm_lt_deriv_boundary
theorem image_norm_le_of_norm_deriv_right_lt_deriv_boundary' {f' : ℝ → E}
(hf : ContinuousOn f (Icc a b)) (hf' : ∀ x ∈ Ico a b, HasDerivWithinAt f (f' x) (Ici x) x)
{B B' : ℝ → ℝ} (ha : ‖f a‖ ≤ B a) (hB : ContinuousOn B (Icc a b))
(hB' : ∀ x ∈ Ico a b, HasDerivWithinAt B (B' x) (Ici x) x)
(bound : ∀ x ∈ Ico a b, ‖f x‖ = B x → ‖f' x‖ < B' x) : ∀ ⦃x⦄, x ∈ Icc a b → ‖f x‖ ≤ B x :=
image_norm_le_of_liminf_right_slope_norm_lt_deriv_boundary hf
(fun x hx _ hr => (hf' x hx).liminf_right_slope_norm_le hr) ha hB hB' bound
#align image_norm_le_of_norm_deriv_right_lt_deriv_boundary' image_norm_le_of_norm_deriv_right_lt_deriv_boundary'
theorem image_norm_le_of_norm_deriv_right_lt_deriv_boundary {f' : ℝ → E}
(hf : ContinuousOn f (Icc a b)) (hf' : ∀ x ∈ Ico a b, HasDerivWithinAt f (f' x) (Ici x) x)
{B B' : ℝ → ℝ} (ha : ‖f a‖ ≤ B a) (hB : ∀ x, HasDerivAt B (B' x) x)
(bound : ∀ x ∈ Ico a b, ‖f x‖ = B x → ‖f' x‖ < B' x) : ∀ ⦃x⦄, x ∈ Icc a b → ‖f x‖ ≤ B x :=
image_norm_le_of_norm_deriv_right_lt_deriv_boundary' hf hf' ha
(fun x _ => (hB x).continuousAt.continuousWithinAt) (fun x _ => (hB x).hasDerivWithinAt) bound
#align image_norm_le_of_norm_deriv_right_lt_deriv_boundary image_norm_le_of_norm_deriv_right_lt_deriv_boundary
theorem image_norm_le_of_norm_deriv_right_le_deriv_boundary' {f' : ℝ → E}
(hf : ContinuousOn f (Icc a b)) (hf' : ∀ x ∈ Ico a b, HasDerivWithinAt f (f' x) (Ici x) x)
{B B' : ℝ → ℝ} (ha : ‖f a‖ ≤ B a) (hB : ContinuousOn B (Icc a b))
(hB' : ∀ x ∈ Ico a b, HasDerivWithinAt B (B' x) (Ici x) x)
(bound : ∀ x ∈ Ico a b, ‖f' x‖ ≤ B' x) : ∀ ⦃x⦄, x ∈ Icc a b → ‖f x‖ ≤ B x :=
image_le_of_liminf_slope_right_le_deriv_boundary (continuous_norm.comp_continuousOn hf) ha hB hB'
fun x hx _ hr => (hf' x hx).liminf_right_slope_norm_le ((bound x hx).trans_lt hr)
#align image_norm_le_of_norm_deriv_right_le_deriv_boundary' image_norm_le_of_norm_deriv_right_le_deriv_boundary'
theorem image_norm_le_of_norm_deriv_right_le_deriv_boundary {f' : ℝ → E}
(hf : ContinuousOn f (Icc a b)) (hf' : ∀ x ∈ Ico a b, HasDerivWithinAt f (f' x) (Ici x) x)
{B B' : ℝ → ℝ} (ha : ‖f a‖ ≤ B a) (hB : ∀ x, HasDerivAt B (B' x) x)
(bound : ∀ x ∈ Ico a b, ‖f' x‖ ≤ B' x) : ∀ ⦃x⦄, x ∈ Icc a b → ‖f x‖ ≤ B x :=
image_norm_le_of_norm_deriv_right_le_deriv_boundary' hf hf' ha
(fun x _ => (hB x).continuousAt.continuousWithinAt) (fun x _ => (hB x).hasDerivWithinAt) bound
#align image_norm_le_of_norm_deriv_right_le_deriv_boundary image_norm_le_of_norm_deriv_right_le_deriv_boundary
theorem norm_image_sub_le_of_norm_deriv_right_le_segment {f' : ℝ → E} {C : ℝ}
(hf : ContinuousOn f (Icc a b)) (hf' : ∀ x ∈ Ico a b, HasDerivWithinAt f (f' x) (Ici x) x)
(bound : ∀ x ∈ Ico a b, ‖f' x‖ ≤ C) : ∀ x ∈ Icc a b, ‖f x - f a‖ ≤ C * (x - a) := by
let g x := f x - f a
have hg : ContinuousOn g (Icc a b) := hf.sub continuousOn_const
have hg' : ∀ x ∈ Ico a b, HasDerivWithinAt g (f' x) (Ici x) x := by
intro x hx
simpa using (hf' x hx).sub (hasDerivWithinAt_const _ _ _)
let B x := C * (x - a)
have hB : ∀ x, HasDerivAt B C x := by
intro x
simpa using (hasDerivAt_const x C).mul ((hasDerivAt_id x).sub (hasDerivAt_const x a))
convert image_norm_le_of_norm_deriv_right_le_deriv_boundary hg hg' _ hB bound
simp only [g, B]; rw [sub_self, norm_zero, sub_self, mul_zero]
#align norm_image_sub_le_of_norm_deriv_right_le_segment norm_image_sub_le_of_norm_deriv_right_le_segment
theorem norm_image_sub_le_of_norm_deriv_le_segment' {f' : ℝ → E} {C : ℝ}
(hf : ∀ x ∈ Icc a b, HasDerivWithinAt f (f' x) (Icc a b) x)
(bound : ∀ x ∈ Ico a b, ‖f' x‖ ≤ C) : ∀ x ∈ Icc a b, ‖f x - f a‖ ≤ C * (x - a) := by
refine
norm_image_sub_le_of_norm_deriv_right_le_segment (fun x hx => (hf x hx).continuousWithinAt)
(fun x hx => ?_) bound
exact (hf x <| Ico_subset_Icc_self hx).mono_of_mem (Icc_mem_nhdsWithin_Ici hx)
#align norm_image_sub_le_of_norm_deriv_le_segment' norm_image_sub_le_of_norm_deriv_le_segment'
theorem norm_image_sub_le_of_norm_deriv_le_segment {C : ℝ} (hf : DifferentiableOn ℝ f (Icc a b))
(bound : ∀ x ∈ Ico a b, ‖derivWithin f (Icc a b) x‖ ≤ C) :
∀ x ∈ Icc a b, ‖f x - f a‖ ≤ C * (x - a) := by
refine norm_image_sub_le_of_norm_deriv_le_segment' ?_ bound
exact fun x hx => (hf x hx).hasDerivWithinAt
#align norm_image_sub_le_of_norm_deriv_le_segment norm_image_sub_le_of_norm_deriv_le_segment
theorem norm_image_sub_le_of_norm_deriv_le_segment_01' {f' : ℝ → E} {C : ℝ}
(hf : ∀ x ∈ Icc (0 : ℝ) 1, HasDerivWithinAt f (f' x) (Icc (0 : ℝ) 1) x)
(bound : ∀ x ∈ Ico (0 : ℝ) 1, ‖f' x‖ ≤ C) : ‖f 1 - f 0‖ ≤ C := by
simpa only [sub_zero, mul_one] using
norm_image_sub_le_of_norm_deriv_le_segment' hf bound 1 (right_mem_Icc.2 zero_le_one)
#align norm_image_sub_le_of_norm_deriv_le_segment_01' norm_image_sub_le_of_norm_deriv_le_segment_01'
theorem norm_image_sub_le_of_norm_deriv_le_segment_01 {C : ℝ}
(hf : DifferentiableOn ℝ f (Icc (0 : ℝ) 1))
(bound : ∀ x ∈ Ico (0 : ℝ) 1, ‖derivWithin f (Icc (0 : ℝ) 1) x‖ ≤ C) : ‖f 1 - f 0‖ ≤ C := by
simpa only [sub_zero, mul_one] using
norm_image_sub_le_of_norm_deriv_le_segment hf bound 1 (right_mem_Icc.2 zero_le_one)
#align norm_image_sub_le_of_norm_deriv_le_segment_01 norm_image_sub_le_of_norm_deriv_le_segment_01
| Mathlib/Analysis/Calculus/MeanValue.lean | 394 | 398 | theorem constant_of_has_deriv_right_zero (hcont : ContinuousOn f (Icc a b))
(hderiv : ∀ x ∈ Ico a b, HasDerivWithinAt f 0 (Ici x) x) : ∀ x ∈ Icc a b, f x = f a := by |
have : ∀ x ∈ Icc a b, ‖f x - f a‖ ≤ 0 * (x - a) := fun x hx =>
norm_image_sub_le_of_norm_deriv_right_le_segment hcont hderiv (fun _ _ => norm_zero.le) x hx
simpa only [zero_mul, norm_le_zero_iff, sub_eq_zero] using this
|
import Mathlib.LinearAlgebra.ExteriorAlgebra.Basic
import Mathlib.LinearAlgebra.CliffordAlgebra.Fold
import Mathlib.LinearAlgebra.CliffordAlgebra.Conjugation
import Mathlib.LinearAlgebra.Dual
#align_import linear_algebra.clifford_algebra.contraction from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a"
open LinearMap (BilinForm)
universe u1 u2 u3
variable {R : Type u1} [CommRing R]
variable {M : Type u2} [AddCommGroup M] [Module R M]
variable (Q : QuadraticForm R M)
namespace CliffordAlgebra
section contractLeft
variable (d d' : Module.Dual R M)
@[simps!]
def contractLeftAux (d : Module.Dual R M) :
M →ₗ[R] CliffordAlgebra Q × CliffordAlgebra Q →ₗ[R] CliffordAlgebra Q :=
haveI v_mul := (Algebra.lmul R (CliffordAlgebra Q)).toLinearMap ∘ₗ ι Q
d.smulRight (LinearMap.fst _ (CliffordAlgebra Q) (CliffordAlgebra Q)) -
v_mul.compl₂ (LinearMap.snd _ (CliffordAlgebra Q) _)
#align clifford_algebra.contract_left_aux CliffordAlgebra.contractLeftAux
theorem contractLeftAux_contractLeftAux (v : M) (x : CliffordAlgebra Q) (fx : CliffordAlgebra Q) :
contractLeftAux Q d v (ι Q v * x, contractLeftAux Q d v (x, fx)) = Q v • fx := by
simp only [contractLeftAux_apply_apply]
rw [mul_sub, ← mul_assoc, ι_sq_scalar, ← Algebra.smul_def, ← sub_add, mul_smul_comm, sub_self,
zero_add]
#align clifford_algebra.contract_left_aux_contract_left_aux CliffordAlgebra.contractLeftAux_contractLeftAux
variable {Q}
def contractLeft : Module.Dual R M →ₗ[R] CliffordAlgebra Q →ₗ[R] CliffordAlgebra Q where
toFun d := foldr' Q (contractLeftAux Q d) (contractLeftAux_contractLeftAux Q d) 0
map_add' d₁ d₂ :=
LinearMap.ext fun x => by
dsimp only
rw [LinearMap.add_apply]
induction' x using CliffordAlgebra.left_induction with r x y hx hy m x hx
· simp_rw [foldr'_algebraMap, smul_zero, zero_add]
· rw [map_add, map_add, map_add, add_add_add_comm, hx, hy]
· rw [foldr'_ι_mul, foldr'_ι_mul, foldr'_ι_mul, hx]
dsimp only [contractLeftAux_apply_apply]
rw [sub_add_sub_comm, mul_add, LinearMap.add_apply, add_smul]
map_smul' c d :=
LinearMap.ext fun x => by
dsimp only
rw [LinearMap.smul_apply, RingHom.id_apply]
induction' x using CliffordAlgebra.left_induction with r x y hx hy m x hx
· simp_rw [foldr'_algebraMap, smul_zero]
· rw [map_add, map_add, smul_add, hx, hy]
· rw [foldr'_ι_mul, foldr'_ι_mul, hx]
dsimp only [contractLeftAux_apply_apply]
rw [LinearMap.smul_apply, smul_assoc, mul_smul_comm, smul_sub]
#align clifford_algebra.contract_left CliffordAlgebra.contractLeft
def contractRight : CliffordAlgebra Q →ₗ[R] Module.Dual R M →ₗ[R] CliffordAlgebra Q :=
LinearMap.flip (LinearMap.compl₂ (LinearMap.compr₂ contractLeft reverse) reverse)
#align clifford_algebra.contract_right CliffordAlgebra.contractRight
theorem contractRight_eq (x : CliffordAlgebra Q) :
contractRight (Q := Q) x d = reverse (contractLeft (R := R) (M := M) d <| reverse x) :=
rfl
#align clifford_algebra.contract_right_eq CliffordAlgebra.contractRight_eq
local infixl:70 "⌋" => contractLeft (R := R) (M := M)
local infixl:70 "⌊" => contractRight (R := R) (M := M) (Q := Q)
-- Porting note: Lean needs to be reminded of this instance otherwise the statement of the
-- next result times out
instance : SMul R (CliffordAlgebra Q) := inferInstance
theorem contractLeft_ι_mul (a : M) (b : CliffordAlgebra Q) :
d⌋(ι Q a * b) = d a • b - ι Q a * (d⌋b) := by
-- Porting note: Lean cannot figure out anymore the third argument
refine foldr'_ι_mul _ _ ?_ _ _ _
exact fun m x fx ↦ contractLeftAux_contractLeftAux Q d m x fx
#align clifford_algebra.contract_left_ι_mul CliffordAlgebra.contractLeft_ι_mul
theorem contractRight_mul_ι (a : M) (b : CliffordAlgebra Q) :
b * ι Q a⌊d = d a • b - b⌊d * ι Q a := by
rw [contractRight_eq, reverse.map_mul, reverse_ι, contractLeft_ι_mul, map_sub, map_smul,
reverse_reverse, reverse.map_mul, reverse_ι, contractRight_eq]
#align clifford_algebra.contract_right_mul_ι CliffordAlgebra.contractRight_mul_ι
theorem contractLeft_algebraMap_mul (r : R) (b : CliffordAlgebra Q) :
d⌋(algebraMap _ _ r * b) = algebraMap _ _ r * (d⌋b) := by
rw [← Algebra.smul_def, map_smul, Algebra.smul_def]
#align clifford_algebra.contract_left_algebra_map_mul CliffordAlgebra.contractLeft_algebraMap_mul
theorem contractLeft_mul_algebraMap (a : CliffordAlgebra Q) (r : R) :
d⌋(a * algebraMap _ _ r) = d⌋a * algebraMap _ _ r := by
rw [← Algebra.commutes, contractLeft_algebraMap_mul, Algebra.commutes]
#align clifford_algebra.contract_left_mul_algebra_map CliffordAlgebra.contractLeft_mul_algebraMap
theorem contractRight_algebraMap_mul (r : R) (b : CliffordAlgebra Q) :
algebraMap _ _ r * b⌊d = algebraMap _ _ r * (b⌊d) := by
rw [← Algebra.smul_def, LinearMap.map_smul₂, Algebra.smul_def]
#align clifford_algebra.contract_right_algebra_map_mul CliffordAlgebra.contractRight_algebraMap_mul
theorem contractRight_mul_algebraMap (a : CliffordAlgebra Q) (r : R) :
a * algebraMap _ _ r⌊d = a⌊d * algebraMap _ _ r := by
rw [← Algebra.commutes, contractRight_algebraMap_mul, Algebra.commutes]
#align clifford_algebra.contract_right_mul_algebra_map CliffordAlgebra.contractRight_mul_algebraMap
variable (Q)
@[simp]
theorem contractLeft_ι (x : M) : d⌋ι Q x = algebraMap R _ (d x) := by
-- Porting note: Lean cannot figure out anymore the third argument
refine (foldr'_ι _ _ ?_ _ _).trans <| by
simp_rw [contractLeftAux_apply_apply, mul_zero, sub_zero,
Algebra.algebraMap_eq_smul_one]
exact fun m x fx ↦ contractLeftAux_contractLeftAux Q d m x fx
#align clifford_algebra.contract_left_ι CliffordAlgebra.contractLeft_ι
@[simp]
theorem contractRight_ι (x : M) : ι Q x⌊d = algebraMap R _ (d x) := by
rw [contractRight_eq, reverse_ι, contractLeft_ι, reverse.commutes]
#align clifford_algebra.contract_right_ι CliffordAlgebra.contractRight_ι
@[simp]
| Mathlib/LinearAlgebra/CliffordAlgebra/Contraction.lean | 181 | 184 | theorem contractLeft_algebraMap (r : R) : d⌋algebraMap R (CliffordAlgebra Q) r = 0 := by |
-- Porting note: Lean cannot figure out anymore the third argument
refine (foldr'_algebraMap _ _ ?_ _ _).trans <| smul_zero _
exact fun m x fx ↦ contractLeftAux_contractLeftAux Q d m x fx
|
import Mathlib.Algebra.CharP.Invertible
import Mathlib.Algebra.Order.Interval.Set.Group
import Mathlib.Analysis.Convex.Segment
import Mathlib.LinearAlgebra.AffineSpace.FiniteDimensional
import Mathlib.Tactic.FieldSimp
#align_import analysis.convex.between from "leanprover-community/mathlib"@"571e13cacbed7bf042fd3058ce27157101433842"
variable (R : Type*) {V V' P P' : Type*}
open AffineEquiv AffineMap
section OrderedRing
variable [OrderedRing R] [AddCommGroup V] [Module R V] [AddTorsor V P]
variable [AddCommGroup V'] [Module R V'] [AddTorsor V' P']
def affineSegment (x y : P) :=
lineMap x y '' Set.Icc (0 : R) 1
#align affine_segment affineSegment
theorem affineSegment_eq_segment (x y : V) : affineSegment R x y = segment R x y := by
rw [segment_eq_image_lineMap, affineSegment]
#align affine_segment_eq_segment affineSegment_eq_segment
theorem affineSegment_comm (x y : P) : affineSegment R x y = affineSegment R y x := by
refine Set.ext fun z => ?_
constructor <;>
· rintro ⟨t, ht, hxy⟩
refine ⟨1 - t, ?_, ?_⟩
· rwa [Set.sub_mem_Icc_iff_right, sub_self, sub_zero]
· rwa [lineMap_apply_one_sub]
#align affine_segment_comm affineSegment_comm
theorem left_mem_affineSegment (x y : P) : x ∈ affineSegment R x y :=
⟨0, Set.left_mem_Icc.2 zero_le_one, lineMap_apply_zero _ _⟩
#align left_mem_affine_segment left_mem_affineSegment
theorem right_mem_affineSegment (x y : P) : y ∈ affineSegment R x y :=
⟨1, Set.right_mem_Icc.2 zero_le_one, lineMap_apply_one _ _⟩
#align right_mem_affine_segment right_mem_affineSegment
@[simp]
theorem affineSegment_same (x : P) : affineSegment R x x = {x} := by
-- Porting note: added as this doesn't do anything in `simp_rw` any more
rw [affineSegment]
-- Note: when adding "simp made no progress" in lean4#2336,
-- had to change `lineMap_same` to `lineMap_same _`. Not sure why?
-- Porting note: added `_ _` and `Function.const`
simp_rw [lineMap_same _, AffineMap.coe_const _ _, Function.const,
(Set.nonempty_Icc.mpr zero_le_one).image_const]
#align affine_segment_same affineSegment_same
variable {R}
@[simp]
theorem affineSegment_image (f : P →ᵃ[R] P') (x y : P) :
f '' affineSegment R x y = affineSegment R (f x) (f y) := by
rw [affineSegment, affineSegment, Set.image_image, ← comp_lineMap]
rfl
#align affine_segment_image affineSegment_image
variable (R)
@[simp]
theorem affineSegment_const_vadd_image (x y : P) (v : V) :
(v +ᵥ ·) '' affineSegment R x y = affineSegment R (v +ᵥ x) (v +ᵥ y) :=
affineSegment_image (AffineEquiv.constVAdd R P v : P →ᵃ[R] P) x y
#align affine_segment_const_vadd_image affineSegment_const_vadd_image
@[simp]
theorem affineSegment_vadd_const_image (x y : V) (p : P) :
(· +ᵥ p) '' affineSegment R x y = affineSegment R (x +ᵥ p) (y +ᵥ p) :=
affineSegment_image (AffineEquiv.vaddConst R p : V →ᵃ[R] P) x y
#align affine_segment_vadd_const_image affineSegment_vadd_const_image
@[simp]
theorem affineSegment_const_vsub_image (x y p : P) :
(p -ᵥ ·) '' affineSegment R x y = affineSegment R (p -ᵥ x) (p -ᵥ y) :=
affineSegment_image (AffineEquiv.constVSub R p : P →ᵃ[R] V) x y
#align affine_segment_const_vsub_image affineSegment_const_vsub_image
@[simp]
theorem affineSegment_vsub_const_image (x y p : P) :
(· -ᵥ p) '' affineSegment R x y = affineSegment R (x -ᵥ p) (y -ᵥ p) :=
affineSegment_image ((AffineEquiv.vaddConst R p).symm : P →ᵃ[R] V) x y
#align affine_segment_vsub_const_image affineSegment_vsub_const_image
variable {R}
@[simp]
theorem mem_const_vadd_affineSegment {x y z : P} (v : V) :
v +ᵥ z ∈ affineSegment R (v +ᵥ x) (v +ᵥ y) ↔ z ∈ affineSegment R x y := by
rw [← affineSegment_const_vadd_image, (AddAction.injective v).mem_set_image]
#align mem_const_vadd_affine_segment mem_const_vadd_affineSegment
@[simp]
theorem mem_vadd_const_affineSegment {x y z : V} (p : P) :
z +ᵥ p ∈ affineSegment R (x +ᵥ p) (y +ᵥ p) ↔ z ∈ affineSegment R x y := by
rw [← affineSegment_vadd_const_image, (vadd_right_injective p).mem_set_image]
#align mem_vadd_const_affine_segment mem_vadd_const_affineSegment
@[simp]
theorem mem_const_vsub_affineSegment {x y z : P} (p : P) :
p -ᵥ z ∈ affineSegment R (p -ᵥ x) (p -ᵥ y) ↔ z ∈ affineSegment R x y := by
rw [← affineSegment_const_vsub_image, (vsub_right_injective p).mem_set_image]
#align mem_const_vsub_affine_segment mem_const_vsub_affineSegment
@[simp]
theorem mem_vsub_const_affineSegment {x y z : P} (p : P) :
z -ᵥ p ∈ affineSegment R (x -ᵥ p) (y -ᵥ p) ↔ z ∈ affineSegment R x y := by
rw [← affineSegment_vsub_const_image, (vsub_left_injective p).mem_set_image]
#align mem_vsub_const_affine_segment mem_vsub_const_affineSegment
variable (R)
def Wbtw (x y z : P) : Prop :=
y ∈ affineSegment R x z
#align wbtw Wbtw
def Sbtw (x y z : P) : Prop :=
Wbtw R x y z ∧ y ≠ x ∧ y ≠ z
#align sbtw Sbtw
variable {R}
lemma mem_segment_iff_wbtw {x y z : V} : y ∈ segment R x z ↔ Wbtw R x y z := by
rw [Wbtw, affineSegment_eq_segment]
theorem Wbtw.map {x y z : P} (h : Wbtw R x y z) (f : P →ᵃ[R] P') : Wbtw R (f x) (f y) (f z) := by
rw [Wbtw, ← affineSegment_image]
exact Set.mem_image_of_mem _ h
#align wbtw.map Wbtw.map
theorem Function.Injective.wbtw_map_iff {x y z : P} {f : P →ᵃ[R] P'} (hf : Function.Injective f) :
Wbtw R (f x) (f y) (f z) ↔ Wbtw R x y z := by
refine ⟨fun h => ?_, fun h => h.map _⟩
rwa [Wbtw, ← affineSegment_image, hf.mem_set_image] at h
#align function.injective.wbtw_map_iff Function.Injective.wbtw_map_iff
theorem Function.Injective.sbtw_map_iff {x y z : P} {f : P →ᵃ[R] P'} (hf : Function.Injective f) :
Sbtw R (f x) (f y) (f z) ↔ Sbtw R x y z := by
simp_rw [Sbtw, hf.wbtw_map_iff, hf.ne_iff]
#align function.injective.sbtw_map_iff Function.Injective.sbtw_map_iff
@[simp]
theorem AffineEquiv.wbtw_map_iff {x y z : P} (f : P ≃ᵃ[R] P') :
Wbtw R (f x) (f y) (f z) ↔ Wbtw R x y z := by
refine Function.Injective.wbtw_map_iff (?_ : Function.Injective f.toAffineMap)
exact f.injective
#align affine_equiv.wbtw_map_iff AffineEquiv.wbtw_map_iff
@[simp]
theorem AffineEquiv.sbtw_map_iff {x y z : P} (f : P ≃ᵃ[R] P') :
Sbtw R (f x) (f y) (f z) ↔ Sbtw R x y z := by
refine Function.Injective.sbtw_map_iff (?_ : Function.Injective f.toAffineMap)
exact f.injective
#align affine_equiv.sbtw_map_iff AffineEquiv.sbtw_map_iff
@[simp]
theorem wbtw_const_vadd_iff {x y z : P} (v : V) :
Wbtw R (v +ᵥ x) (v +ᵥ y) (v +ᵥ z) ↔ Wbtw R x y z :=
mem_const_vadd_affineSegment _
#align wbtw_const_vadd_iff wbtw_const_vadd_iff
@[simp]
theorem wbtw_vadd_const_iff {x y z : V} (p : P) :
Wbtw R (x +ᵥ p) (y +ᵥ p) (z +ᵥ p) ↔ Wbtw R x y z :=
mem_vadd_const_affineSegment _
#align wbtw_vadd_const_iff wbtw_vadd_const_iff
@[simp]
theorem wbtw_const_vsub_iff {x y z : P} (p : P) :
Wbtw R (p -ᵥ x) (p -ᵥ y) (p -ᵥ z) ↔ Wbtw R x y z :=
mem_const_vsub_affineSegment _
#align wbtw_const_vsub_iff wbtw_const_vsub_iff
@[simp]
theorem wbtw_vsub_const_iff {x y z : P} (p : P) :
Wbtw R (x -ᵥ p) (y -ᵥ p) (z -ᵥ p) ↔ Wbtw R x y z :=
mem_vsub_const_affineSegment _
#align wbtw_vsub_const_iff wbtw_vsub_const_iff
@[simp]
theorem sbtw_const_vadd_iff {x y z : P} (v : V) :
Sbtw R (v +ᵥ x) (v +ᵥ y) (v +ᵥ z) ↔ Sbtw R x y z := by
rw [Sbtw, Sbtw, wbtw_const_vadd_iff, (AddAction.injective v).ne_iff,
(AddAction.injective v).ne_iff]
#align sbtw_const_vadd_iff sbtw_const_vadd_iff
@[simp]
theorem sbtw_vadd_const_iff {x y z : V} (p : P) :
Sbtw R (x +ᵥ p) (y +ᵥ p) (z +ᵥ p) ↔ Sbtw R x y z := by
rw [Sbtw, Sbtw, wbtw_vadd_const_iff, (vadd_right_injective p).ne_iff,
(vadd_right_injective p).ne_iff]
#align sbtw_vadd_const_iff sbtw_vadd_const_iff
@[simp]
theorem sbtw_const_vsub_iff {x y z : P} (p : P) :
Sbtw R (p -ᵥ x) (p -ᵥ y) (p -ᵥ z) ↔ Sbtw R x y z := by
rw [Sbtw, Sbtw, wbtw_const_vsub_iff, (vsub_right_injective p).ne_iff,
(vsub_right_injective p).ne_iff]
#align sbtw_const_vsub_iff sbtw_const_vsub_iff
@[simp]
theorem sbtw_vsub_const_iff {x y z : P} (p : P) :
Sbtw R (x -ᵥ p) (y -ᵥ p) (z -ᵥ p) ↔ Sbtw R x y z := by
rw [Sbtw, Sbtw, wbtw_vsub_const_iff, (vsub_left_injective p).ne_iff,
(vsub_left_injective p).ne_iff]
#align sbtw_vsub_const_iff sbtw_vsub_const_iff
theorem Sbtw.wbtw {x y z : P} (h : Sbtw R x y z) : Wbtw R x y z :=
h.1
#align sbtw.wbtw Sbtw.wbtw
theorem Sbtw.ne_left {x y z : P} (h : Sbtw R x y z) : y ≠ x :=
h.2.1
#align sbtw.ne_left Sbtw.ne_left
theorem Sbtw.left_ne {x y z : P} (h : Sbtw R x y z) : x ≠ y :=
h.2.1.symm
#align sbtw.left_ne Sbtw.left_ne
theorem Sbtw.ne_right {x y z : P} (h : Sbtw R x y z) : y ≠ z :=
h.2.2
#align sbtw.ne_right Sbtw.ne_right
theorem Sbtw.right_ne {x y z : P} (h : Sbtw R x y z) : z ≠ y :=
h.2.2.symm
#align sbtw.right_ne Sbtw.right_ne
theorem Sbtw.mem_image_Ioo {x y z : P} (h : Sbtw R x y z) :
y ∈ lineMap x z '' Set.Ioo (0 : R) 1 := by
rcases h with ⟨⟨t, ht, rfl⟩, hyx, hyz⟩
rcases Set.eq_endpoints_or_mem_Ioo_of_mem_Icc ht with (rfl | rfl | ho)
· exfalso
exact hyx (lineMap_apply_zero _ _)
· exfalso
exact hyz (lineMap_apply_one _ _)
· exact ⟨t, ho, rfl⟩
#align sbtw.mem_image_Ioo Sbtw.mem_image_Ioo
theorem Wbtw.mem_affineSpan {x y z : P} (h : Wbtw R x y z) : y ∈ line[R, x, z] := by
rcases h with ⟨r, ⟨-, rfl⟩⟩
exact lineMap_mem_affineSpan_pair _ _ _
#align wbtw.mem_affine_span Wbtw.mem_affineSpan
theorem wbtw_comm {x y z : P} : Wbtw R x y z ↔ Wbtw R z y x := by
rw [Wbtw, Wbtw, affineSegment_comm]
#align wbtw_comm wbtw_comm
alias ⟨Wbtw.symm, _⟩ := wbtw_comm
#align wbtw.symm Wbtw.symm
theorem sbtw_comm {x y z : P} : Sbtw R x y z ↔ Sbtw R z y x := by
rw [Sbtw, Sbtw, wbtw_comm, ← and_assoc, ← and_assoc, and_right_comm]
#align sbtw_comm sbtw_comm
alias ⟨Sbtw.symm, _⟩ := sbtw_comm
#align sbtw.symm Sbtw.symm
variable (R)
@[simp]
theorem wbtw_self_left (x y : P) : Wbtw R x x y :=
left_mem_affineSegment _ _ _
#align wbtw_self_left wbtw_self_left
@[simp]
theorem wbtw_self_right (x y : P) : Wbtw R x y y :=
right_mem_affineSegment _ _ _
#align wbtw_self_right wbtw_self_right
@[simp]
theorem wbtw_self_iff {x y : P} : Wbtw R x y x ↔ y = x := by
refine ⟨fun h => ?_, fun h => ?_⟩
· -- Porting note: Originally `simpa [Wbtw, affineSegment] using h`
have ⟨_, _, h₂⟩ := h
rw [h₂.symm, lineMap_same_apply]
· rw [h]
exact wbtw_self_left R x x
#align wbtw_self_iff wbtw_self_iff
@[simp]
theorem not_sbtw_self_left (x y : P) : ¬Sbtw R x x y :=
fun h => h.ne_left rfl
#align not_sbtw_self_left not_sbtw_self_left
@[simp]
theorem not_sbtw_self_right (x y : P) : ¬Sbtw R x y y :=
fun h => h.ne_right rfl
#align not_sbtw_self_right not_sbtw_self_right
variable {R}
theorem Wbtw.left_ne_right_of_ne_left {x y z : P} (h : Wbtw R x y z) (hne : y ≠ x) : x ≠ z := by
rintro rfl
rw [wbtw_self_iff] at h
exact hne h
#align wbtw.left_ne_right_of_ne_left Wbtw.left_ne_right_of_ne_left
theorem Wbtw.left_ne_right_of_ne_right {x y z : P} (h : Wbtw R x y z) (hne : y ≠ z) : x ≠ z := by
rintro rfl
rw [wbtw_self_iff] at h
exact hne h
#align wbtw.left_ne_right_of_ne_right Wbtw.left_ne_right_of_ne_right
theorem Sbtw.left_ne_right {x y z : P} (h : Sbtw R x y z) : x ≠ z :=
h.wbtw.left_ne_right_of_ne_left h.2.1
#align sbtw.left_ne_right Sbtw.left_ne_right
theorem sbtw_iff_mem_image_Ioo_and_ne [NoZeroSMulDivisors R V] {x y z : P} :
Sbtw R x y z ↔ y ∈ lineMap x z '' Set.Ioo (0 : R) 1 ∧ x ≠ z := by
refine ⟨fun h => ⟨h.mem_image_Ioo, h.left_ne_right⟩, fun h => ?_⟩
rcases h with ⟨⟨t, ht, rfl⟩, hxz⟩
refine ⟨⟨t, Set.mem_Icc_of_Ioo ht, rfl⟩, ?_⟩
rw [lineMap_apply, ← @vsub_ne_zero V, ← @vsub_ne_zero V _ _ _ _ z, vadd_vsub_assoc, vsub_self,
vadd_vsub_assoc, ← neg_vsub_eq_vsub_rev z x, ← @neg_one_smul R, ← add_smul, ← sub_eq_add_neg]
simp [smul_ne_zero, sub_eq_zero, ht.1.ne.symm, ht.2.ne, hxz.symm]
#align sbtw_iff_mem_image_Ioo_and_ne sbtw_iff_mem_image_Ioo_and_ne
variable (R)
@[simp]
theorem not_sbtw_self (x y : P) : ¬Sbtw R x y x :=
fun h => h.left_ne_right rfl
#align not_sbtw_self not_sbtw_self
theorem wbtw_swap_left_iff [NoZeroSMulDivisors R V] {x y : P} (z : P) :
Wbtw R x y z ∧ Wbtw R y x z ↔ x = y := by
constructor
· rintro ⟨hxyz, hyxz⟩
rcases hxyz with ⟨ty, hty, rfl⟩
rcases hyxz with ⟨tx, htx, hx⟩
rw [lineMap_apply, lineMap_apply, ← add_vadd] at hx
rw [← @vsub_eq_zero_iff_eq V, vadd_vsub, vsub_vadd_eq_vsub_sub, smul_sub, smul_smul, ← sub_smul,
← add_smul, smul_eq_zero] at hx
rcases hx with (h | h)
· nth_rw 1 [← mul_one tx] at h
rw [← mul_sub, add_eq_zero_iff_neg_eq] at h
have h' : ty = 0 := by
refine le_antisymm ?_ hty.1
rw [← h, Left.neg_nonpos_iff]
exact mul_nonneg htx.1 (sub_nonneg.2 hty.2)
simp [h']
· rw [vsub_eq_zero_iff_eq] at h
rw [h, lineMap_same_apply]
· rintro rfl
exact ⟨wbtw_self_left _ _ _, wbtw_self_left _ _ _⟩
#align wbtw_swap_left_iff wbtw_swap_left_iff
theorem wbtw_swap_right_iff [NoZeroSMulDivisors R V] (x : P) {y z : P} :
Wbtw R x y z ∧ Wbtw R x z y ↔ y = z := by
rw [wbtw_comm, wbtw_comm (z := y), eq_comm]
exact wbtw_swap_left_iff R x
#align wbtw_swap_right_iff wbtw_swap_right_iff
theorem wbtw_rotate_iff [NoZeroSMulDivisors R V] (x : P) {y z : P} :
Wbtw R x y z ∧ Wbtw R z x y ↔ x = y := by rw [wbtw_comm, wbtw_swap_right_iff, eq_comm]
#align wbtw_rotate_iff wbtw_rotate_iff
variable {R}
theorem Wbtw.swap_left_iff [NoZeroSMulDivisors R V] {x y z : P} (h : Wbtw R x y z) :
Wbtw R y x z ↔ x = y := by rw [← wbtw_swap_left_iff R z, and_iff_right h]
#align wbtw.swap_left_iff Wbtw.swap_left_iff
theorem Wbtw.swap_right_iff [NoZeroSMulDivisors R V] {x y z : P} (h : Wbtw R x y z) :
Wbtw R x z y ↔ y = z := by rw [← wbtw_swap_right_iff R x, and_iff_right h]
#align wbtw.swap_right_iff Wbtw.swap_right_iff
theorem Wbtw.rotate_iff [NoZeroSMulDivisors R V] {x y z : P} (h : Wbtw R x y z) :
Wbtw R z x y ↔ x = y := by rw [← wbtw_rotate_iff R x, and_iff_right h]
#align wbtw.rotate_iff Wbtw.rotate_iff
theorem Sbtw.not_swap_left [NoZeroSMulDivisors R V] {x y z : P} (h : Sbtw R x y z) :
¬Wbtw R y x z := fun hs => h.left_ne (h.wbtw.swap_left_iff.1 hs)
#align sbtw.not_swap_left Sbtw.not_swap_left
theorem Sbtw.not_swap_right [NoZeroSMulDivisors R V] {x y z : P} (h : Sbtw R x y z) :
¬Wbtw R x z y := fun hs => h.ne_right (h.wbtw.swap_right_iff.1 hs)
#align sbtw.not_swap_right Sbtw.not_swap_right
theorem Sbtw.not_rotate [NoZeroSMulDivisors R V] {x y z : P} (h : Sbtw R x y z) : ¬Wbtw R z x y :=
fun hs => h.left_ne (h.wbtw.rotate_iff.1 hs)
#align sbtw.not_rotate Sbtw.not_rotate
@[simp]
theorem wbtw_lineMap_iff [NoZeroSMulDivisors R V] {x y : P} {r : R} :
Wbtw R x (lineMap x y r) y ↔ x = y ∨ r ∈ Set.Icc (0 : R) 1 := by
by_cases hxy : x = y
· rw [hxy, lineMap_same_apply]
simp
rw [or_iff_right hxy, Wbtw, affineSegment, (lineMap_injective R hxy).mem_set_image]
#align wbtw_line_map_iff wbtw_lineMap_iff
@[simp]
theorem sbtw_lineMap_iff [NoZeroSMulDivisors R V] {x y : P} {r : R} :
Sbtw R x (lineMap x y r) y ↔ x ≠ y ∧ r ∈ Set.Ioo (0 : R) 1 := by
rw [sbtw_iff_mem_image_Ioo_and_ne, and_comm, and_congr_right]
intro hxy
rw [(lineMap_injective R hxy).mem_set_image]
#align sbtw_line_map_iff sbtw_lineMap_iff
@[simp]
theorem wbtw_mul_sub_add_iff [NoZeroDivisors R] {x y r : R} :
Wbtw R x (r * (y - x) + x) y ↔ x = y ∨ r ∈ Set.Icc (0 : R) 1 :=
wbtw_lineMap_iff
#align wbtw_mul_sub_add_iff wbtw_mul_sub_add_iff
@[simp]
theorem sbtw_mul_sub_add_iff [NoZeroDivisors R] {x y r : R} :
Sbtw R x (r * (y - x) + x) y ↔ x ≠ y ∧ r ∈ Set.Ioo (0 : R) 1 :=
sbtw_lineMap_iff
#align sbtw_mul_sub_add_iff sbtw_mul_sub_add_iff
@[simp]
theorem wbtw_zero_one_iff {x : R} : Wbtw R 0 x 1 ↔ x ∈ Set.Icc (0 : R) 1 := by
rw [Wbtw, affineSegment, Set.mem_image]
simp_rw [lineMap_apply_ring]
simp
#align wbtw_zero_one_iff wbtw_zero_one_iff
@[simp]
theorem wbtw_one_zero_iff {x : R} : Wbtw R 1 x 0 ↔ x ∈ Set.Icc (0 : R) 1 := by
rw [wbtw_comm, wbtw_zero_one_iff]
#align wbtw_one_zero_iff wbtw_one_zero_iff
@[simp]
theorem sbtw_zero_one_iff {x : R} : Sbtw R 0 x 1 ↔ x ∈ Set.Ioo (0 : R) 1 := by
rw [Sbtw, wbtw_zero_one_iff, Set.mem_Icc, Set.mem_Ioo]
exact
⟨fun h => ⟨h.1.1.lt_of_ne (Ne.symm h.2.1), h.1.2.lt_of_ne h.2.2⟩, fun h =>
⟨⟨h.1.le, h.2.le⟩, h.1.ne', h.2.ne⟩⟩
#align sbtw_zero_one_iff sbtw_zero_one_iff
@[simp]
theorem sbtw_one_zero_iff {x : R} : Sbtw R 1 x 0 ↔ x ∈ Set.Ioo (0 : R) 1 := by
rw [sbtw_comm, sbtw_zero_one_iff]
#align sbtw_one_zero_iff sbtw_one_zero_iff
theorem Wbtw.trans_left {w x y z : P} (h₁ : Wbtw R w y z) (h₂ : Wbtw R w x y) : Wbtw R w x z := by
rcases h₁ with ⟨t₁, ht₁, rfl⟩
rcases h₂ with ⟨t₂, ht₂, rfl⟩
refine ⟨t₂ * t₁, ⟨mul_nonneg ht₂.1 ht₁.1, mul_le_one ht₂.2 ht₁.1 ht₁.2⟩, ?_⟩
rw [lineMap_apply, lineMap_apply, lineMap_vsub_left, smul_smul]
#align wbtw.trans_left Wbtw.trans_left
theorem Wbtw.trans_right {w x y z : P} (h₁ : Wbtw R w x z) (h₂ : Wbtw R x y z) : Wbtw R w y z := by
rw [wbtw_comm] at *
exact h₁.trans_left h₂
#align wbtw.trans_right Wbtw.trans_right
theorem Wbtw.trans_sbtw_left [NoZeroSMulDivisors R V] {w x y z : P} (h₁ : Wbtw R w y z)
(h₂ : Sbtw R w x y) : Sbtw R w x z := by
refine ⟨h₁.trans_left h₂.wbtw, h₂.ne_left, ?_⟩
rintro rfl
exact h₂.right_ne ((wbtw_swap_right_iff R w).1 ⟨h₁, h₂.wbtw⟩)
#align wbtw.trans_sbtw_left Wbtw.trans_sbtw_left
theorem Wbtw.trans_sbtw_right [NoZeroSMulDivisors R V] {w x y z : P} (h₁ : Wbtw R w x z)
(h₂ : Sbtw R x y z) : Sbtw R w y z := by
rw [wbtw_comm] at *
rw [sbtw_comm] at *
exact h₁.trans_sbtw_left h₂
#align wbtw.trans_sbtw_right Wbtw.trans_sbtw_right
theorem Sbtw.trans_left [NoZeroSMulDivisors R V] {w x y z : P} (h₁ : Sbtw R w y z)
(h₂ : Sbtw R w x y) : Sbtw R w x z :=
h₁.wbtw.trans_sbtw_left h₂
#align sbtw.trans_left Sbtw.trans_left
theorem Sbtw.trans_right [NoZeroSMulDivisors R V] {w x y z : P} (h₁ : Sbtw R w x z)
(h₂ : Sbtw R x y z) : Sbtw R w y z :=
h₁.wbtw.trans_sbtw_right h₂
#align sbtw.trans_right Sbtw.trans_right
theorem Wbtw.trans_left_ne [NoZeroSMulDivisors R V] {w x y z : P} (h₁ : Wbtw R w y z)
(h₂ : Wbtw R w x y) (h : y ≠ z) : x ≠ z := by
rintro rfl
exact h (h₁.swap_right_iff.1 h₂)
#align wbtw.trans_left_ne Wbtw.trans_left_ne
theorem Wbtw.trans_right_ne [NoZeroSMulDivisors R V] {w x y z : P} (h₁ : Wbtw R w x z)
(h₂ : Wbtw R x y z) (h : w ≠ x) : w ≠ y := by
rintro rfl
exact h (h₁.swap_left_iff.1 h₂)
#align wbtw.trans_right_ne Wbtw.trans_right_ne
theorem Sbtw.trans_wbtw_left_ne [NoZeroSMulDivisors R V] {w x y z : P} (h₁ : Sbtw R w y z)
(h₂ : Wbtw R w x y) : x ≠ z :=
h₁.wbtw.trans_left_ne h₂ h₁.ne_right
#align sbtw.trans_wbtw_left_ne Sbtw.trans_wbtw_left_ne
theorem Sbtw.trans_wbtw_right_ne [NoZeroSMulDivisors R V] {w x y z : P} (h₁ : Sbtw R w x z)
(h₂ : Wbtw R x y z) : w ≠ y :=
h₁.wbtw.trans_right_ne h₂ h₁.left_ne
#align sbtw.trans_wbtw_right_ne Sbtw.trans_wbtw_right_ne
| Mathlib/Analysis/Convex/Between.lean | 525 | 546 | theorem Sbtw.affineCombination_of_mem_affineSpan_pair [NoZeroDivisors R] [NoZeroSMulDivisors R V]
{ι : Type*} {p : ι → P} (ha : AffineIndependent R p) {w w₁ w₂ : ι → R} {s : Finset ι}
(hw : ∑ i ∈ s, w i = 1) (hw₁ : ∑ i ∈ s, w₁ i = 1) (hw₂ : ∑ i ∈ s, w₂ i = 1)
(h : s.affineCombination R p w ∈
line[R, s.affineCombination R p w₁, s.affineCombination R p w₂])
{i : ι} (his : i ∈ s) (hs : Sbtw R (w₁ i) (w i) (w₂ i)) :
Sbtw R (s.affineCombination R p w₁) (s.affineCombination R p w)
(s.affineCombination R p w₂) := by |
rw [affineCombination_mem_affineSpan_pair ha hw hw₁ hw₂] at h
rcases h with ⟨r, hr⟩
rw [hr i his, sbtw_mul_sub_add_iff] at hs
change ∀ i ∈ s, w i = (r • (w₂ - w₁) + w₁) i at hr
rw [s.affineCombination_congr hr fun _ _ => rfl]
rw [← s.weightedVSub_vadd_affineCombination, s.weightedVSub_const_smul,
← s.affineCombination_vsub, ← lineMap_apply, sbtw_lineMap_iff, and_iff_left hs.2,
← @vsub_ne_zero V, s.affineCombination_vsub]
intro hz
have hw₁w₂ : (∑ i ∈ s, (w₁ - w₂) i) = 0 := by
simp_rw [Pi.sub_apply, Finset.sum_sub_distrib, hw₁, hw₂, sub_self]
refine hs.1 ?_
have ha' := ha s (w₁ - w₂) hw₁w₂ hz i his
rwa [Pi.sub_apply, sub_eq_zero] at ha'
|
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]
| Mathlib/Analysis/Fourier/AddCircle.lean | 163 | 164 | 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
|
import Mathlib.AlgebraicGeometry.Gluing
import Mathlib.CategoryTheory.Limits.Opposites
import Mathlib.AlgebraicGeometry.AffineScheme
import Mathlib.CategoryTheory.Limits.Shapes.Diagonal
#align_import algebraic_geometry.pullbacks from "leanprover-community/mathlib"@"7316286ff2942aa14e540add9058c6b0aa1c8070"
set_option linter.uppercaseLean3 false
universe v u
noncomputable section
open CategoryTheory CategoryTheory.Limits AlgebraicGeometry
namespace AlgebraicGeometry.Scheme
namespace Pullback
variable {C : Type u} [Category.{v} C]
variable {X Y Z : Scheme.{u}} (𝒰 : OpenCover.{u} X) (f : X ⟶ Z) (g : Y ⟶ Z)
variable [∀ i, HasPullback (𝒰.map i ≫ f) g]
def v (i j : 𝒰.J) : Scheme :=
pullback ((pullback.fst : pullback (𝒰.map i ≫ f) g ⟶ _) ≫ 𝒰.map i) (𝒰.map j)
#align algebraic_geometry.Scheme.pullback.V AlgebraicGeometry.Scheme.Pullback.v
def t (i j : 𝒰.J) : v 𝒰 f g i j ⟶ v 𝒰 f g j i := by
have : HasPullback (pullback.snd ≫ 𝒰.map i ≫ f) g :=
hasPullback_assoc_symm (𝒰.map j) (𝒰.map i) (𝒰.map i ≫ f) g
have : HasPullback (pullback.snd ≫ 𝒰.map j ≫ f) g :=
hasPullback_assoc_symm (𝒰.map i) (𝒰.map j) (𝒰.map j ≫ f) g
refine (pullbackSymmetry ..).hom ≫ (pullbackAssoc ..).inv ≫ ?_
refine ?_ ≫ (pullbackAssoc ..).hom ≫ (pullbackSymmetry ..).hom
refine pullback.map _ _ _ _ (pullbackSymmetry _ _).hom (𝟙 _) (𝟙 _) ?_ ?_
· rw [pullbackSymmetry_hom_comp_snd_assoc, pullback.condition_assoc, Category.comp_id]
· rw [Category.comp_id, Category.id_comp]
#align algebraic_geometry.Scheme.pullback.t AlgebraicGeometry.Scheme.Pullback.t
@[simp, reassoc]
theorem t_fst_fst (i j : 𝒰.J) : t 𝒰 f g i j ≫ pullback.fst ≫ pullback.fst = pullback.snd := by
simp only [t, Category.assoc, pullbackSymmetry_hom_comp_fst_assoc, pullbackAssoc_hom_snd_fst,
pullback.lift_fst_assoc, pullbackSymmetry_hom_comp_snd, pullbackAssoc_inv_fst_fst,
pullbackSymmetry_hom_comp_fst]
#align algebraic_geometry.Scheme.pullback.t_fst_fst AlgebraicGeometry.Scheme.Pullback.t_fst_fst
@[simp, reassoc]
theorem t_fst_snd (i j : 𝒰.J) :
t 𝒰 f g i j ≫ pullback.fst ≫ pullback.snd = pullback.fst ≫ pullback.snd := by
simp only [t, Category.assoc, pullbackSymmetry_hom_comp_fst_assoc, pullbackAssoc_hom_snd_snd,
pullback.lift_snd, Category.comp_id, pullbackAssoc_inv_snd, pullbackSymmetry_hom_comp_snd_assoc]
#align algebraic_geometry.Scheme.pullback.t_fst_snd AlgebraicGeometry.Scheme.Pullback.t_fst_snd
@[simp, reassoc]
theorem t_snd (i j : 𝒰.J) : t 𝒰 f g i j ≫ pullback.snd = pullback.fst ≫ pullback.fst := by
simp only [t, Category.assoc, pullbackSymmetry_hom_comp_snd, pullbackAssoc_hom_fst,
pullback.lift_fst_assoc, pullbackSymmetry_hom_comp_fst, pullbackAssoc_inv_fst_snd,
pullbackSymmetry_hom_comp_snd_assoc]
#align algebraic_geometry.Scheme.pullback.t_snd AlgebraicGeometry.Scheme.Pullback.t_snd
theorem t_id (i : 𝒰.J) : t 𝒰 f g i i = 𝟙 _ := by
apply pullback.hom_ext <;> rw [Category.id_comp]
· apply pullback.hom_ext
· rw [← cancel_mono (𝒰.map i)]; simp only [pullback.condition, Category.assoc, t_fst_fst]
· simp only [Category.assoc, t_fst_snd]
· rw [← cancel_mono (𝒰.map i)]; simp only [pullback.condition, t_snd, Category.assoc]
#align algebraic_geometry.Scheme.pullback.t_id AlgebraicGeometry.Scheme.Pullback.t_id
abbrev fV (i j : 𝒰.J) : v 𝒰 f g i j ⟶ pullback (𝒰.map i ≫ f) g :=
pullback.fst
#align algebraic_geometry.Scheme.pullback.fV AlgebraicGeometry.Scheme.Pullback.fV
def t' (i j k : 𝒰.J) :
pullback (fV 𝒰 f g i j) (fV 𝒰 f g i k) ⟶ pullback (fV 𝒰 f g j k) (fV 𝒰 f g j i) := by
refine (pullbackRightPullbackFstIso ..).hom ≫ ?_
refine ?_ ≫ (pullbackSymmetry _ _).hom
refine ?_ ≫ (pullbackRightPullbackFstIso ..).inv
refine pullback.map _ _ _ _ (t 𝒰 f g i j) (𝟙 _) (𝟙 _) ?_ ?_
· simp_rw [Category.comp_id, t_fst_fst_assoc, ← pullback.condition]
· rw [Category.comp_id, Category.id_comp]
#align algebraic_geometry.Scheme.pullback.t' AlgebraicGeometry.Scheme.Pullback.t'
@[simp, reassoc]
theorem t'_fst_fst_fst (i j k : 𝒰.J) :
t' 𝒰 f g i j k ≫ pullback.fst ≫ pullback.fst ≫ pullback.fst = pullback.fst ≫ pullback.snd := by
simp only [t', Category.assoc, pullbackSymmetry_hom_comp_fst_assoc,
pullbackRightPullbackFstIso_inv_snd_fst_assoc, pullback.lift_fst_assoc, t_fst_fst,
pullbackRightPullbackFstIso_hom_fst_assoc]
#align algebraic_geometry.Scheme.pullback.t'_fst_fst_fst AlgebraicGeometry.Scheme.Pullback.t'_fst_fst_fst
@[simp, reassoc]
theorem t'_fst_fst_snd (i j k : 𝒰.J) :
t' 𝒰 f g i j k ≫ pullback.fst ≫ pullback.fst ≫ pullback.snd =
pullback.fst ≫ pullback.fst ≫ pullback.snd := by
simp only [t', Category.assoc, pullbackSymmetry_hom_comp_fst_assoc,
pullbackRightPullbackFstIso_inv_snd_fst_assoc, pullback.lift_fst_assoc, t_fst_snd,
pullbackRightPullbackFstIso_hom_fst_assoc]
#align algebraic_geometry.Scheme.pullback.t'_fst_fst_snd AlgebraicGeometry.Scheme.Pullback.t'_fst_fst_snd
@[simp, reassoc]
theorem t'_fst_snd (i j k : 𝒰.J) :
t' 𝒰 f g i j k ≫ pullback.fst ≫ pullback.snd = pullback.snd ≫ pullback.snd := by
simp only [t', Category.assoc, pullbackSymmetry_hom_comp_fst_assoc,
pullbackRightPullbackFstIso_inv_snd_snd, pullback.lift_snd, Category.comp_id,
pullbackRightPullbackFstIso_hom_snd]
#align algebraic_geometry.Scheme.pullback.t'_fst_snd AlgebraicGeometry.Scheme.Pullback.t'_fst_snd
@[simp, reassoc]
theorem t'_snd_fst_fst (i j k : 𝒰.J) :
t' 𝒰 f g i j k ≫ pullback.snd ≫ pullback.fst ≫ pullback.fst = pullback.fst ≫ pullback.snd := by
simp only [t', Category.assoc, pullbackSymmetry_hom_comp_snd_assoc,
pullbackRightPullbackFstIso_inv_fst_assoc, pullback.lift_fst_assoc, t_fst_fst,
pullbackRightPullbackFstIso_hom_fst_assoc]
#align algebraic_geometry.Scheme.pullback.t'_snd_fst_fst AlgebraicGeometry.Scheme.Pullback.t'_snd_fst_fst
@[simp, reassoc]
theorem t'_snd_fst_snd (i j k : 𝒰.J) :
t' 𝒰 f g i j k ≫ pullback.snd ≫ pullback.fst ≫ pullback.snd =
pullback.fst ≫ pullback.fst ≫ pullback.snd := by
simp only [t', Category.assoc, pullbackSymmetry_hom_comp_snd_assoc,
pullbackRightPullbackFstIso_inv_fst_assoc, pullback.lift_fst_assoc, t_fst_snd,
pullbackRightPullbackFstIso_hom_fst_assoc]
#align algebraic_geometry.Scheme.pullback.t'_snd_fst_snd AlgebraicGeometry.Scheme.Pullback.t'_snd_fst_snd
@[simp, reassoc]
theorem t'_snd_snd (i j k : 𝒰.J) :
t' 𝒰 f g i j k ≫ pullback.snd ≫ pullback.snd = pullback.fst ≫ pullback.fst ≫ pullback.fst := by
simp only [t', Category.assoc, pullbackSymmetry_hom_comp_snd_assoc,
pullbackRightPullbackFstIso_inv_fst_assoc, pullback.lift_fst_assoc, t_snd,
pullbackRightPullbackFstIso_hom_fst_assoc]
#align algebraic_geometry.Scheme.pullback.t'_snd_snd AlgebraicGeometry.Scheme.Pullback.t'_snd_snd
theorem cocycle_fst_fst_fst (i j k : 𝒰.J) :
t' 𝒰 f g i j k ≫ t' 𝒰 f g j k i ≫ t' 𝒰 f g k i j ≫ pullback.fst ≫ pullback.fst ≫ pullback.fst =
pullback.fst ≫ pullback.fst ≫ pullback.fst := by
simp only [t'_fst_fst_fst, t'_fst_snd, t'_snd_snd]
#align algebraic_geometry.Scheme.pullback.cocycle_fst_fst_fst AlgebraicGeometry.Scheme.Pullback.cocycle_fst_fst_fst
theorem cocycle_fst_fst_snd (i j k : 𝒰.J) :
t' 𝒰 f g i j k ≫ t' 𝒰 f g j k i ≫ t' 𝒰 f g k i j ≫ pullback.fst ≫ pullback.fst ≫ pullback.snd =
pullback.fst ≫ pullback.fst ≫ pullback.snd := by
simp only [t'_fst_fst_snd]
#align algebraic_geometry.Scheme.pullback.cocycle_fst_fst_snd AlgebraicGeometry.Scheme.Pullback.cocycle_fst_fst_snd
theorem cocycle_fst_snd (i j k : 𝒰.J) :
t' 𝒰 f g i j k ≫ t' 𝒰 f g j k i ≫ t' 𝒰 f g k i j ≫ pullback.fst ≫ pullback.snd =
pullback.fst ≫ pullback.snd := by
simp only [t'_fst_snd, t'_snd_snd, t'_fst_fst_fst]
#align algebraic_geometry.Scheme.pullback.cocycle_fst_snd AlgebraicGeometry.Scheme.Pullback.cocycle_fst_snd
theorem cocycle_snd_fst_fst (i j k : 𝒰.J) :
t' 𝒰 f g i j k ≫ t' 𝒰 f g j k i ≫ t' 𝒰 f g k i j ≫ pullback.snd ≫ pullback.fst ≫ pullback.fst =
pullback.snd ≫ pullback.fst ≫ pullback.fst := by
rw [← cancel_mono (𝒰.map i)]
simp only [pullback.condition_assoc, t'_snd_fst_fst, t'_fst_snd, t'_snd_snd]
#align algebraic_geometry.Scheme.pullback.cocycle_snd_fst_fst AlgebraicGeometry.Scheme.Pullback.cocycle_snd_fst_fst
theorem cocycle_snd_fst_snd (i j k : 𝒰.J) :
t' 𝒰 f g i j k ≫ t' 𝒰 f g j k i ≫ t' 𝒰 f g k i j ≫ pullback.snd ≫ pullback.fst ≫ pullback.snd =
pullback.snd ≫ pullback.fst ≫ pullback.snd := by
simp only [pullback.condition_assoc, t'_snd_fst_snd]
#align algebraic_geometry.Scheme.pullback.cocycle_snd_fst_snd AlgebraicGeometry.Scheme.Pullback.cocycle_snd_fst_snd
theorem cocycle_snd_snd (i j k : 𝒰.J) :
t' 𝒰 f g i j k ≫ t' 𝒰 f g j k i ≫ t' 𝒰 f g k i j ≫ pullback.snd ≫ pullback.snd =
pullback.snd ≫ pullback.snd := by
simp only [t'_snd_snd, t'_fst_fst_fst, t'_fst_snd]
#align algebraic_geometry.Scheme.pullback.cocycle_snd_snd AlgebraicGeometry.Scheme.Pullback.cocycle_snd_snd
-- `by tidy` should solve it, but it times out.
theorem cocycle (i j k : 𝒰.J) : t' 𝒰 f g i j k ≫ t' 𝒰 f g j k i ≫ t' 𝒰 f g k i j = 𝟙 _ := by
apply pullback.hom_ext <;> rw [Category.id_comp]
· apply pullback.hom_ext
· apply pullback.hom_ext
· simp_rw [Category.assoc, cocycle_fst_fst_fst 𝒰 f g i j k]
· simp_rw [Category.assoc, cocycle_fst_fst_snd 𝒰 f g i j k]
· simp_rw [Category.assoc, cocycle_fst_snd 𝒰 f g i j k]
· apply pullback.hom_ext
· apply pullback.hom_ext
· simp_rw [Category.assoc, cocycle_snd_fst_fst 𝒰 f g i j k]
· simp_rw [Category.assoc, cocycle_snd_fst_snd 𝒰 f g i j k]
· simp_rw [Category.assoc, cocycle_snd_snd 𝒰 f g i j k]
#align algebraic_geometry.Scheme.pullback.cocycle AlgebraicGeometry.Scheme.Pullback.cocycle
@[simps U V f t t', simps (config := .lemmasOnly) J]
def gluing : Scheme.GlueData.{u} where
J := 𝒰.J
U i := pullback (𝒰.map i ≫ f) g
V := fun ⟨i, j⟩ => v 𝒰 f g i j
-- `p⁻¹(Uᵢ ∩ Uⱼ)` where `p : Uᵢ ×[Z] Y ⟶ Uᵢ ⟶ X`.
f i j := pullback.fst
f_id i := inferInstance
f_open := inferInstance
t i j := t 𝒰 f g i j
t_id i := t_id 𝒰 f g i
t' i j k := t' 𝒰 f g i j k
t_fac i j k := by
apply pullback.hom_ext
on_goal 1 => apply pullback.hom_ext
all_goals
simp only [t'_snd_fst_fst, t'_snd_fst_snd, t'_snd_snd, t_fst_fst, t_fst_snd, t_snd,
Category.assoc]
cocycle i j k := cocycle 𝒰 f g i j k
#align algebraic_geometry.Scheme.pullback.gluing AlgebraicGeometry.Scheme.Pullback.gluing
@[simp]
lemma gluing_ι (j : 𝒰.J) :
(gluing 𝒰 f g).ι j = Multicoequalizer.π (gluing 𝒰 f g).diagram j := rfl
def p1 : (gluing 𝒰 f g).glued ⟶ X := by
apply Multicoequalizer.desc (gluing 𝒰 f g).diagram _ fun i ↦ pullback.fst ≫ 𝒰.map i
simp [t_fst_fst_assoc, ← pullback.condition]
#align algebraic_geometry.Scheme.pullback.p1 AlgebraicGeometry.Scheme.Pullback.p1
def p2 : (gluing 𝒰 f g).glued ⟶ Y := by
apply Multicoequalizer.desc _ _ fun i ↦ pullback.snd
simp [t_fst_snd]
#align algebraic_geometry.Scheme.pullback.p2 AlgebraicGeometry.Scheme.Pullback.p2
theorem p_comm : p1 𝒰 f g ≫ f = p2 𝒰 f g ≫ g := by
apply Multicoequalizer.hom_ext
simp [p1, p2, pullback.condition]
#align algebraic_geometry.Scheme.pullback.p_comm AlgebraicGeometry.Scheme.Pullback.p_comm
variable (s : PullbackCone f g)
def gluedLiftPullbackMap (i j : 𝒰.J) :
pullback ((𝒰.pullbackCover s.fst).map i) ((𝒰.pullbackCover s.fst).map j) ⟶
(gluing 𝒰 f g).V ⟨i, j⟩ := by
refine (pullbackRightPullbackFstIso _ _ _).hom ≫ ?_
refine pullback.map _ _ _ _ ?_ (𝟙 _) (𝟙 _) ?_ ?_
· exact (pullbackSymmetry _ _).hom ≫
pullback.map _ _ _ _ (𝟙 _) s.snd f (Category.id_comp _).symm s.condition
· simpa using pullback.condition
· simp only [Category.comp_id, Category.id_comp]
#align algebraic_geometry.Scheme.pullback.glued_lift_pullback_map AlgebraicGeometry.Scheme.Pullback.gluedLiftPullbackMap
@[reassoc]
theorem gluedLiftPullbackMap_fst (i j : 𝒰.J) :
gluedLiftPullbackMap 𝒰 f g s i j ≫ pullback.fst =
pullback.fst ≫
(pullbackSymmetry _ _).hom ≫
pullback.map _ _ _ _ (𝟙 _) s.snd f (Category.id_comp _).symm s.condition := by
simp [gluedLiftPullbackMap]
#align algebraic_geometry.Scheme.pullback.glued_lift_pullback_map_fst AlgebraicGeometry.Scheme.Pullback.gluedLiftPullbackMap_fst
@[reassoc]
theorem gluedLiftPullbackMap_snd (i j : 𝒰.J) :
gluedLiftPullbackMap 𝒰 f g s i j ≫ pullback.snd = pullback.snd ≫ pullback.snd := by
simp [gluedLiftPullbackMap]
#align algebraic_geometry.Scheme.pullback.glued_lift_pullback_map_snd AlgebraicGeometry.Scheme.Pullback.gluedLiftPullbackMap_snd
def gluedLift : s.pt ⟶ (gluing 𝒰 f g).glued := by
fapply (𝒰.pullbackCover s.fst).glueMorphisms
· exact fun i ↦ (pullbackSymmetry _ _).hom ≫
pullback.map _ _ _ _ (𝟙 _) s.snd f (Category.id_comp _).symm s.condition ≫ (gluing 𝒰 f g).ι i
intro i j
rw [← gluedLiftPullbackMap_fst_assoc, ← gluing_f, ← (gluing 𝒰 f g).glue_condition i j,
gluing_t, gluing_f]
simp_rw [← Category.assoc]
congr 1
apply pullback.hom_ext <;> simp_rw [Category.assoc]
· rw [t_fst_fst, gluedLiftPullbackMap_snd]
congr 1
rw [← Iso.inv_comp_eq, pullbackSymmetry_inv_comp_snd, pullback.lift_fst, Category.comp_id]
· rw [t_fst_snd, gluedLiftPullbackMap_fst_assoc, pullback.lift_snd, pullback.lift_snd]
simp_rw [pullbackSymmetry_hom_comp_snd_assoc]
exact pullback.condition_assoc _
#align algebraic_geometry.Scheme.pullback.glued_lift AlgebraicGeometry.Scheme.Pullback.gluedLift
theorem gluedLift_p1 : gluedLift 𝒰 f g s ≫ p1 𝒰 f g = s.fst := by
rw [← cancel_epi (𝒰.pullbackCover s.fst).fromGlued]
apply Multicoequalizer.hom_ext
intro b
simp_rw [OpenCover.fromGlued, Multicoequalizer.π_desc_assoc, gluedLift, ← Category.assoc]
simp_rw [(𝒰.pullbackCover s.fst).ι_glueMorphisms]
simp [p1, pullback.condition]
#align algebraic_geometry.Scheme.pullback.glued_lift_p1 AlgebraicGeometry.Scheme.Pullback.gluedLift_p1
theorem gluedLift_p2 : gluedLift 𝒰 f g s ≫ p2 𝒰 f g = s.snd := by
rw [← cancel_epi (𝒰.pullbackCover s.fst).fromGlued]
apply Multicoequalizer.hom_ext
intro b
simp_rw [OpenCover.fromGlued, Multicoequalizer.π_desc_assoc, gluedLift, ← Category.assoc]
simp_rw [(𝒰.pullbackCover s.fst).ι_glueMorphisms]
simp [p2, pullback.condition]
#align algebraic_geometry.Scheme.pullback.glued_lift_p2 AlgebraicGeometry.Scheme.Pullback.gluedLift_p2
def pullbackFstιToV (i j : 𝒰.J) :
pullback (pullback.fst : pullback (p1 𝒰 f g) (𝒰.map i) ⟶ _) ((gluing 𝒰 f g).ι j) ⟶
v 𝒰 f g j i :=
(pullbackSymmetry _ _ ≪≫ pullbackRightPullbackFstIso (p1 𝒰 f g) (𝒰.map i) _).hom ≫
(pullback.congrHom (Multicoequalizer.π_desc ..) rfl).hom
#align algebraic_geometry.Scheme.pullback.pullback_fst_ι_to_V AlgebraicGeometry.Scheme.Pullback.pullbackFstιToV
@[simp, reassoc]
theorem pullbackFstιToV_fst (i j : 𝒰.J) :
pullbackFstιToV 𝒰 f g i j ≫ pullback.fst = pullback.snd := by
simp [pullbackFstιToV, p1]
#align algebraic_geometry.Scheme.pullback.pullback_fst_ι_to_V_fst AlgebraicGeometry.Scheme.Pullback.pullbackFstιToV_fst
@[simp, reassoc]
theorem pullbackFstιToV_snd (i j : 𝒰.J) :
pullbackFstιToV 𝒰 f g i j ≫ pullback.snd = pullback.fst ≫ pullback.snd := by
simp [pullbackFstιToV, p1]
#align algebraic_geometry.Scheme.pullback.pullback_fst_ι_to_V_snd AlgebraicGeometry.Scheme.Pullback.pullbackFstιToV_snd
theorem lift_comp_ι (i : 𝒰.J) :
pullback.lift pullback.snd (pullback.fst ≫ p2 𝒰 f g)
(by rw [← pullback.condition_assoc, Category.assoc, p_comm]) ≫
(gluing 𝒰 f g).ι i =
(pullback.fst : pullback (p1 𝒰 f g) (𝒰.map i) ⟶ _) := by
apply ((gluing 𝒰 f g).openCover.pullbackCover pullback.fst).hom_ext
intro j
dsimp only [OpenCover.pullbackCover]
trans pullbackFstιToV 𝒰 f g i j ≫ fV 𝒰 f g j i ≫ (gluing 𝒰 f g).ι _
· rw [← show _ = fV 𝒰 f g j i ≫ _ from (gluing 𝒰 f g).glue_condition j i]
simp_rw [← Category.assoc]
congr 1
rw [gluing_f, gluing_t]
apply pullback.hom_ext <;> simp_rw [Category.assoc]
· simp_rw [t_fst_fst, pullback.lift_fst, pullbackFstιToV_snd, GlueData.openCover_map]
· simp_rw [t_fst_snd, pullback.lift_snd, pullbackFstιToV_fst_assoc, pullback.condition_assoc,
GlueData.openCover_map, p2]
simp
· rw [pullback.condition, ← Category.assoc]
simp_rw [pullbackFstιToV_fst, GlueData.openCover_map]
#align algebraic_geometry.Scheme.pullback.lift_comp_ι AlgebraicGeometry.Scheme.Pullback.lift_comp_ι
def pullbackP1Iso (i : 𝒰.J) : pullback (p1 𝒰 f g) (𝒰.map i) ≅ pullback (𝒰.map i ≫ f) g := by
fconstructor
· exact
pullback.lift pullback.snd (pullback.fst ≫ p2 𝒰 f g)
(by rw [← pullback.condition_assoc, Category.assoc, p_comm])
· apply pullback.lift ((gluing 𝒰 f g).ι i) pullback.fst
rw [gluing_ι, p1, Multicoequalizer.π_desc]
· apply pullback.hom_ext
· simpa using lift_comp_ι 𝒰 f g i
· simp_rw [Category.assoc, pullback.lift_snd, pullback.lift_fst, Category.id_comp]
· apply pullback.hom_ext
· simp_rw [Category.assoc, pullback.lift_fst, pullback.lift_snd, Category.id_comp]
· simp [p2]
#align algebraic_geometry.Scheme.pullback.pullback_p1_iso AlgebraicGeometry.Scheme.Pullback.pullbackP1Iso
@[simp, reassoc]
theorem pullbackP1Iso_hom_fst (i : 𝒰.J) :
(pullbackP1Iso 𝒰 f g i).hom ≫ pullback.fst = pullback.snd := by
simp_rw [pullbackP1Iso, pullback.lift_fst]
#align algebraic_geometry.Scheme.pullback.pullback_p1_iso_hom_fst AlgebraicGeometry.Scheme.Pullback.pullbackP1Iso_hom_fst
@[simp, reassoc]
theorem pullbackP1Iso_hom_snd (i : 𝒰.J) :
(pullbackP1Iso 𝒰 f g i).hom ≫ pullback.snd = pullback.fst ≫ p2 𝒰 f g := by
simp_rw [pullbackP1Iso, pullback.lift_snd]
#align algebraic_geometry.Scheme.pullback.pullback_p1_iso_hom_snd AlgebraicGeometry.Scheme.Pullback.pullbackP1Iso_hom_snd
@[simp, reassoc]
theorem pullbackP1Iso_inv_fst (i : 𝒰.J) :
(pullbackP1Iso 𝒰 f g i).inv ≫ pullback.fst = (gluing 𝒰 f g).ι i := by
simp_rw [pullbackP1Iso, pullback.lift_fst]
#align algebraic_geometry.Scheme.pullback.pullback_p1_iso_inv_fst AlgebraicGeometry.Scheme.Pullback.pullbackP1Iso_inv_fst
@[simp, reassoc]
theorem pullbackP1Iso_inv_snd (i : 𝒰.J) :
(pullbackP1Iso 𝒰 f g i).inv ≫ pullback.snd = pullback.fst := by
simp_rw [pullbackP1Iso, pullback.lift_snd]
#align algebraic_geometry.Scheme.pullback.pullback_p1_iso_inv_snd AlgebraicGeometry.Scheme.Pullback.pullbackP1Iso_inv_snd
@[simp, reassoc]
| Mathlib/AlgebraicGeometry/Pullbacks.lean | 425 | 427 | theorem pullbackP1Iso_hom_ι (i : 𝒰.J) :
(pullbackP1Iso 𝒰 f g i).hom ≫ Multicoequalizer.π (gluing 𝒰 f g).diagram i = pullback.fst := by |
rw [← gluing_ι, ← pullbackP1Iso_inv_fst, Iso.hom_inv_id_assoc]
|
import Mathlib.MeasureTheory.Measure.Haar.InnerProductSpace
import Mathlib.MeasureTheory.Measure.Lebesgue.EqHaar
import Mathlib.MeasureTheory.Integral.SetIntegral
#align_import measure_theory.measure.haar.normed_space from "leanprover-community/mathlib"@"b84aee748341da06a6d78491367e2c0e9f15e8a5"
noncomputable section
open scoped NNReal ENNReal Pointwise Topology
open Inv Set Function MeasureTheory.Measure Filter
open FiniteDimensional
namespace MeasureTheory
namespace Measure
example {E : Type*} [NormedAddCommGroup E] [NormedSpace ℝ E] [Nontrivial E] [FiniteDimensional ℝ E]
[MeasurableSpace E] [BorelSpace E] (μ : Measure E) [IsAddHaarMeasure μ] : NoAtoms μ := by
infer_instance
variable {E : Type*} [NormedAddCommGroup E] [NormedSpace ℝ E] [MeasurableSpace E] [BorelSpace E]
[FiniteDimensional ℝ E] (μ : Measure E) [IsAddHaarMeasure μ] {F : Type*} [NormedAddCommGroup F]
[NormedSpace ℝ F]
variable {s : Set E}
theorem integral_comp_smul (f : E → F) (R : ℝ) :
∫ x, f (R • x) ∂μ = |(R ^ finrank ℝ E)⁻¹| • ∫ x, f x ∂μ := by
by_cases hF : CompleteSpace F; swap
· simp [integral, hF]
rcases eq_or_ne R 0 with (rfl | hR)
· simp only [zero_smul, integral_const]
rcases Nat.eq_zero_or_pos (finrank ℝ E) with (hE | hE)
· have : Subsingleton E := finrank_zero_iff.1 hE
have : f = fun _ => f 0 := by ext x; rw [Subsingleton.elim x 0]
conv_rhs => rw [this]
simp only [hE, pow_zero, inv_one, abs_one, one_smul, integral_const]
· have : Nontrivial E := finrank_pos_iff.1 hE
simp only [zero_pow hE.ne', measure_univ_of_isAddLeftInvariant, ENNReal.top_toReal, zero_smul,
inv_zero, abs_zero]
· calc
(∫ x, f (R • x) ∂μ) = ∫ y, f y ∂Measure.map (fun x => R • x) μ :=
(integral_map_equiv (Homeomorph.smul (isUnit_iff_ne_zero.2 hR).unit).toMeasurableEquiv
f).symm
_ = |(R ^ finrank ℝ E)⁻¹| • ∫ x, f x ∂μ := by
simp only [map_addHaar_smul μ hR, integral_smul_measure, ENNReal.toReal_ofReal, abs_nonneg]
#align measure_theory.measure.integral_comp_smul MeasureTheory.Measure.integral_comp_smul
theorem integral_comp_smul_of_nonneg (f : E → F) (R : ℝ) {hR : 0 ≤ R} :
∫ x, f (R • x) ∂μ = (R ^ finrank ℝ E)⁻¹ • ∫ x, f x ∂μ := by
rw [integral_comp_smul μ f R, abs_of_nonneg (inv_nonneg.2 (pow_nonneg hR _))]
#align measure_theory.measure.integral_comp_smul_of_nonneg MeasureTheory.Measure.integral_comp_smul_of_nonneg
theorem integral_comp_inv_smul (f : E → F) (R : ℝ) :
∫ x, f (R⁻¹ • x) ∂μ = |R ^ finrank ℝ E| • ∫ x, f x ∂μ := by
rw [integral_comp_smul μ f R⁻¹, inv_pow, inv_inv]
#align measure_theory.measure.integral_comp_inv_smul MeasureTheory.Measure.integral_comp_inv_smul
theorem integral_comp_inv_smul_of_nonneg (f : E → F) {R : ℝ} (hR : 0 ≤ R) :
∫ x, f (R⁻¹ • x) ∂μ = R ^ finrank ℝ E • ∫ x, f x ∂μ := by
rw [integral_comp_inv_smul μ f R, abs_of_nonneg (pow_nonneg hR _)]
#align measure_theory.measure.integral_comp_inv_smul_of_nonneg MeasureTheory.Measure.integral_comp_inv_smul_of_nonneg
theorem setIntegral_comp_smul (f : E → F) {R : ℝ} (s : Set E) (hR : R ≠ 0) :
∫ x in s, f (R • x) ∂μ = |(R ^ finrank ℝ E)⁻¹| • ∫ x in R • s, f x ∂μ := by
let e : E ≃ᵐ E := (Homeomorph.smul (Units.mk0 R hR)).toMeasurableEquiv
calc
∫ x in s, f (R • x) ∂μ
= ∫ x in e ⁻¹' (e.symm ⁻¹' s), f (e x) ∂μ := by simp [← preimage_comp]; rfl
_ = ∫ y in e.symm ⁻¹' s, f y ∂map (fun x ↦ R • x) μ := (setIntegral_map_equiv _ _ _).symm
_ = |(R ^ finrank ℝ E)⁻¹| • ∫ y in e.symm ⁻¹' s, f y ∂μ := by
simp [map_addHaar_smul μ hR, integral_smul_measure, ENNReal.toReal_ofReal, abs_nonneg]
_ = |(R ^ finrank ℝ E)⁻¹| • ∫ x in R • s, f x ∂μ := by
congr
ext y
rw [mem_smul_set_iff_inv_smul_mem₀ hR]
rfl
@[deprecated (since := "2024-04-17")]
alias set_integral_comp_smul := setIntegral_comp_smul
| Mathlib/MeasureTheory/Measure/Haar/NormedSpace.lean | 128 | 130 | theorem setIntegral_comp_smul_of_pos (f : E → F) {R : ℝ} (s : Set E) (hR : 0 < R) :
∫ x in s, f (R • x) ∂μ = (R ^ finrank ℝ E)⁻¹ • ∫ x in R • s, f x ∂μ := by |
rw [setIntegral_comp_smul μ f s hR.ne', abs_of_nonneg (inv_nonneg.2 (pow_nonneg hR.le _))]
|
import Mathlib.Algebra.Order.Ring.Rat
import Mathlib.Tactic.NormNum.Inv
import Mathlib.Tactic.NormNum.Pow
import Mathlib.Util.AtomM
set_option autoImplicit true
namespace Mathlib.Tactic
namespace Ring
open Mathlib.Meta Qq NormNum Lean.Meta AtomM
open Lean (MetaM Expr mkRawNatLit)
def instCommSemiringNat : CommSemiring ℕ := inferInstance
def sℕ : Q(CommSemiring ℕ) := q(instCommSemiringNat)
-- In this file, we would like to use multi-character auto-implicits.
set_option relaxedAutoImplicit true
mutual
inductive ExBase : ∀ {α : Q(Type u)}, Q(CommSemiring $α) → (e : Q($α)) → Type
| atom (id : ℕ) : ExBase sα e
| sum (_ : ExSum sα e) : ExBase sα e
inductive ExProd : ∀ {α : Q(Type u)}, Q(CommSemiring $α) → (e : Q($α)) → Type
| const (value : ℚ) (hyp : Option Expr := none) : ExProd sα e
| mul {α : Q(Type u)} {sα : Q(CommSemiring $α)} {x : Q($α)} {e : Q(ℕ)} {b : Q($α)} :
ExBase sα x → ExProd sℕ e → ExProd sα b → ExProd sα q($x ^ $e * $b)
inductive ExSum : ∀ {α : Q(Type u)}, Q(CommSemiring $α) → (e : Q($α)) → Type
| zero {α : Q(Type u)} {sα : Q(CommSemiring $α)} : ExSum sα q(0 : $α)
| add {α : Q(Type u)} {sα : Q(CommSemiring $α)} {a b : Q($α)} :
ExProd sα a → ExSum sα b → ExSum sα q($a + $b)
end
mutual -- partial only to speed up compilation
partial def ExBase.eq : ExBase sα a → ExBase sα b → Bool
| .atom i, .atom j => i == j
| .sum a, .sum b => a.eq b
| _, _ => false
@[inherit_doc ExBase.eq]
partial def ExProd.eq : ExProd sα a → ExProd sα b → Bool
| .const i _, .const j _ => i == j
| .mul a₁ a₂ a₃, .mul b₁ b₂ b₃ => a₁.eq b₁ && a₂.eq b₂ && a₃.eq b₃
| _, _ => false
@[inherit_doc ExBase.eq]
partial def ExSum.eq : ExSum sα a → ExSum sα b → Bool
| .zero, .zero => true
| .add a₁ a₂, .add b₁ b₂ => a₁.eq b₁ && a₂.eq b₂
| _, _ => false
end
mutual -- partial only to speed up compilation
partial def ExBase.cmp : ExBase sα a → ExBase sα b → Ordering
| .atom i, .atom j => compare i j
| .sum a, .sum b => a.cmp b
| .atom .., .sum .. => .lt
| .sum .., .atom .. => .gt
@[inherit_doc ExBase.cmp]
partial def ExProd.cmp : ExProd sα a → ExProd sα b → Ordering
| .const i _, .const j _ => compare i j
| .mul a₁ a₂ a₃, .mul b₁ b₂ b₃ => (a₁.cmp b₁).then (a₂.cmp b₂) |>.then (a₃.cmp b₃)
| .const _ _, .mul .. => .lt
| .mul .., .const _ _ => .gt
@[inherit_doc ExBase.cmp]
partial def ExSum.cmp : ExSum sα a → ExSum sα b → Ordering
| .zero, .zero => .eq
| .add a₁ a₂, .add b₁ b₂ => (a₁.cmp b₁).then (a₂.cmp b₂)
| .zero, .add .. => .lt
| .add .., .zero => .gt
end
instance : Inhabited (Σ e, (ExBase sα) e) := ⟨default, .atom 0⟩
instance : Inhabited (Σ e, (ExSum sα) e) := ⟨_, .zero⟩
instance : Inhabited (Σ e, (ExProd sα) e) := ⟨default, .const 0 none⟩
mutual
partial def ExBase.cast : ExBase sα a → Σ a, ExBase sβ a
| .atom i => ⟨a, .atom i⟩
| .sum a => let ⟨_, vb⟩ := a.cast; ⟨_, .sum vb⟩
partial def ExProd.cast : ExProd sα a → Σ a, ExProd sβ a
| .const i h => ⟨a, .const i h⟩
| .mul a₁ a₂ a₃ => ⟨_, .mul a₁.cast.2 a₂ a₃.cast.2⟩
partial def ExSum.cast : ExSum sα a → Σ a, ExSum sβ a
| .zero => ⟨_, .zero⟩
| .add a₁ a₂ => ⟨_, .add a₁.cast.2 a₂.cast.2⟩
end
structure Result {α : Q(Type u)} (E : Q($α) → Type) (e : Q($α)) where
expr : Q($α)
val : E expr
proof : Q($e = $expr)
instance [Inhabited (Σ e, E e)] : Inhabited (Result E e) :=
let ⟨e', v⟩ : Σ e, E e := default; ⟨e', v, default⟩
variable {α : Q(Type u)} (sα : Q(CommSemiring $α)) [CommSemiring R]
def ExProd.mkNat (n : ℕ) : (e : Q($α)) × ExProd sα e :=
let lit : Q(ℕ) := mkRawNatLit n
⟨q(($lit).rawCast : $α), .const n none⟩
def ExProd.mkNegNat (_ : Q(Ring $α)) (n : ℕ) : (e : Q($α)) × ExProd sα e :=
let lit : Q(ℕ) := mkRawNatLit n
⟨q((Int.negOfNat $lit).rawCast : $α), .const (-n) none⟩
def ExProd.mkRat (_ : Q(DivisionRing $α)) (q : ℚ) (n : Q(ℤ)) (d : Q(ℕ)) (h : Expr) :
(e : Q($α)) × ExProd sα e :=
⟨q(Rat.rawCast $n $d : $α), .const q h⟩
section
variable {sα}
def ExBase.toProd (va : ExBase sα a) (vb : ExProd sℕ b) :
ExProd sα q($a ^ $b * (nat_lit 1).rawCast) := .mul va vb (.const 1 none)
def ExProd.toSum (v : ExProd sα e) : ExSum sα q($e + 0) := .add v .zero
def ExProd.coeff : ExProd sα e → ℚ
| .const q _ => q
| .mul _ _ v => v.coeff
end
inductive Overlap (e : Q($α)) where
| zero (_ : Q(IsNat $e (nat_lit 0)))
| nonzero (_ : Result (ExProd sα) e)
theorem add_overlap_pf (x : R) (e) (pq_pf : a + b = c) :
x ^ e * a + x ^ e * b = x ^ e * c := by subst_vars; simp [mul_add]
theorem add_overlap_pf_zero (x : R) (e) :
IsNat (a + b) (nat_lit 0) → IsNat (x ^ e * a + x ^ e * b) (nat_lit 0)
| ⟨h⟩ => ⟨by simp [h, ← mul_add]⟩
def evalAddOverlap (va : ExProd sα a) (vb : ExProd sα b) : Option (Overlap sα q($a + $b)) :=
match va, vb with
| .const za ha, .const zb hb => do
let ra := Result.ofRawRat za a ha; let rb := Result.ofRawRat zb b hb
let res ← NormNum.evalAdd.core q($a + $b) q(HAdd.hAdd) a b ra rb
match res with
| .isNat _ (.lit (.natVal 0)) p => pure <| .zero p
| rc =>
let ⟨zc, hc⟩ ← rc.toRatNZ
let ⟨c, pc⟩ := rc.toRawEq
pure <| .nonzero ⟨c, .const zc hc, pc⟩
| .mul (x := a₁) (e := a₂) va₁ va₂ va₃, .mul vb₁ vb₂ vb₃ => do
guard (va₁.eq vb₁ && va₂.eq vb₂)
match ← evalAddOverlap va₃ vb₃ with
| .zero p => pure <| .zero (q(add_overlap_pf_zero $a₁ $a₂ $p) : Expr)
| .nonzero ⟨_, vc, p⟩ =>
pure <| .nonzero ⟨_, .mul va₁ va₂ vc, (q(add_overlap_pf $a₁ $a₂ $p) : Expr)⟩
| _, _ => none
theorem add_pf_zero_add (b : R) : 0 + b = b := by simp
theorem add_pf_add_zero (a : R) : a + 0 = a := by simp
theorem add_pf_add_overlap
(_ : a₁ + b₁ = c₁) (_ : a₂ + b₂ = c₂) : (a₁ + a₂ : R) + (b₁ + b₂) = c₁ + c₂ := by
subst_vars; simp [add_assoc, add_left_comm]
theorem add_pf_add_overlap_zero
(h : IsNat (a₁ + b₁) (nat_lit 0)) (h₄ : a₂ + b₂ = c) : (a₁ + a₂ : R) + (b₁ + b₂) = c := by
subst_vars; rw [add_add_add_comm, h.1, Nat.cast_zero, add_pf_zero_add]
theorem add_pf_add_lt (a₁ : R) (_ : a₂ + b = c) : (a₁ + a₂) + b = a₁ + c := by simp [*, add_assoc]
theorem add_pf_add_gt (b₁ : R) (_ : a + b₂ = c) : a + (b₁ + b₂) = b₁ + c := by
subst_vars; simp [add_left_comm]
partial def evalAdd (va : ExSum sα a) (vb : ExSum sα b) : Result (ExSum sα) q($a + $b) :=
match va, vb with
| .zero, vb => ⟨b, vb, q(add_pf_zero_add $b)⟩
| va, .zero => ⟨a, va, q(add_pf_add_zero $a)⟩
| .add (a := a₁) (b := _a₂) va₁ va₂, .add (a := b₁) (b := _b₂) vb₁ vb₂ =>
match evalAddOverlap sα va₁ vb₁ with
| some (.nonzero ⟨_, vc₁, pc₁⟩) =>
let ⟨_, vc₂, pc₂⟩ := evalAdd va₂ vb₂
⟨_, .add vc₁ vc₂, q(add_pf_add_overlap $pc₁ $pc₂)⟩
| some (.zero pc₁) =>
let ⟨c₂, vc₂, pc₂⟩ := evalAdd va₂ vb₂
⟨c₂, vc₂, q(add_pf_add_overlap_zero $pc₁ $pc₂)⟩
| none =>
if let .lt := va₁.cmp vb₁ then
let ⟨_c, vc, (pc : Q($_a₂ + ($b₁ + $_b₂) = $_c))⟩ := evalAdd va₂ vb
⟨_, .add va₁ vc, q(add_pf_add_lt $a₁ $pc)⟩
else
let ⟨_c, vc, (pc : Q($a₁ + $_a₂ + $_b₂ = $_c))⟩ := evalAdd va vb₂
⟨_, .add vb₁ vc, q(add_pf_add_gt $b₁ $pc)⟩
theorem one_mul (a : R) : (nat_lit 1).rawCast * a = a := by simp [Nat.rawCast]
theorem mul_one (a : R) : a * (nat_lit 1).rawCast = a := by simp [Nat.rawCast]
theorem mul_pf_left (a₁ : R) (a₂) (_ : a₃ * b = c) : (a₁ ^ a₂ * a₃ : R) * b = a₁ ^ a₂ * c := by
subst_vars; rw [mul_assoc]
theorem mul_pf_right (b₁ : R) (b₂) (_ : a * b₃ = c) : a * (b₁ ^ b₂ * b₃) = b₁ ^ b₂ * c := by
subst_vars; rw [mul_left_comm]
| Mathlib/Tactic/Ring/Basic.lean | 367 | 369 | theorem mul_pp_pf_overlap (x : R) (_ : ea + eb = e) (_ : a₂ * b₂ = c) :
(x ^ ea * a₂ : R) * (x ^ eb * b₂) = x ^ e * c := by |
subst_vars; simp [pow_add, mul_mul_mul_comm]
|
import Mathlib.Data.Int.Range
import Mathlib.Data.ZMod.Basic
import Mathlib.NumberTheory.MulChar.Basic
#align_import number_theory.legendre_symbol.zmod_char from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a"
namespace ZMod
section QuadCharModP
@[simps]
def χ₄ : MulChar (ZMod 4) ℤ where
toFun := (![0, 1, 0, -1] : ZMod 4 → ℤ)
map_one' := rfl
map_mul' := by decide
map_nonunit' := by decide
#align zmod.χ₄ ZMod.χ₄
theorem isQuadratic_χ₄ : χ₄.IsQuadratic := by
intro a
-- Porting note (#11043): was `decide!`
fin_cases a
all_goals decide
#align zmod.is_quadratic_χ₄ ZMod.isQuadratic_χ₄
theorem χ₄_nat_mod_four (n : ℕ) : χ₄ n = χ₄ (n % 4 : ℕ) := by rw [← ZMod.natCast_mod n 4]
#align zmod.χ₄_nat_mod_four ZMod.χ₄_nat_mod_four
theorem χ₄_int_mod_four (n : ℤ) : χ₄ n = χ₄ (n % 4 : ℤ) := by
rw [← ZMod.intCast_mod n 4]
norm_cast
#align zmod.χ₄_int_mod_four ZMod.χ₄_int_mod_four
theorem χ₄_int_eq_if_mod_four (n : ℤ) :
χ₄ n = if n % 2 = 0 then 0 else if n % 4 = 1 then 1 else -1 := by
have help : ∀ m : ℤ, 0 ≤ m → m < 4 → χ₄ m = if m % 2 = 0 then 0 else if m = 1 then 1 else -1 := by
decide
rw [← Int.emod_emod_of_dvd n (by decide : (2 : ℤ) ∣ 4), ← ZMod.intCast_mod n 4]
exact help (n % 4) (Int.emod_nonneg n (by norm_num)) (Int.emod_lt n (by norm_num))
#align zmod.χ₄_int_eq_if_mod_four ZMod.χ₄_int_eq_if_mod_four
theorem χ₄_nat_eq_if_mod_four (n : ℕ) :
χ₄ n = if n % 2 = 0 then 0 else if n % 4 = 1 then 1 else -1 :=
mod_cast χ₄_int_eq_if_mod_four n
#align zmod.χ₄_nat_eq_if_mod_four ZMod.χ₄_nat_eq_if_mod_four
theorem χ₄_eq_neg_one_pow {n : ℕ} (hn : n % 2 = 1) : χ₄ n = (-1) ^ (n / 2) := by
rw [χ₄_nat_eq_if_mod_four]
simp only [hn, Nat.one_ne_zero, if_false]
conv_rhs => -- Porting note: was `nth_rw`
arg 2; rw [← Nat.div_add_mod n 4]
enter [1, 1, 1]; rw [(by norm_num : 4 = 2 * 2)]
rw [mul_assoc, add_comm, Nat.add_mul_div_left _ _ (by norm_num : 0 < 2), pow_add, pow_mul,
neg_one_sq, one_pow, mul_one]
have help : ∀ m : ℕ, m < 4 → m % 2 = 1 → ite (m = 1) (1 : ℤ) (-1) = (-1) ^ (m / 2) := by decide
exact
help (n % 4) (Nat.mod_lt n (by norm_num))
((Nat.mod_mod_of_dvd n (by decide : 2 ∣ 4)).trans hn)
#align zmod.χ₄_eq_neg_one_pow ZMod.χ₄_eq_neg_one_pow
theorem χ₄_nat_one_mod_four {n : ℕ} (hn : n % 4 = 1) : χ₄ n = 1 := by
rw [χ₄_nat_mod_four, hn]
rfl
#align zmod.χ₄_nat_one_mod_four ZMod.χ₄_nat_one_mod_four
theorem χ₄_nat_three_mod_four {n : ℕ} (hn : n % 4 = 3) : χ₄ n = -1 := by
rw [χ₄_nat_mod_four, hn]
rfl
#align zmod.χ₄_nat_three_mod_four ZMod.χ₄_nat_three_mod_four
theorem χ₄_int_one_mod_four {n : ℤ} (hn : n % 4 = 1) : χ₄ n = 1 := by
rw [χ₄_int_mod_four, hn]
rfl
#align zmod.χ₄_int_one_mod_four ZMod.χ₄_int_one_mod_four
| Mathlib/NumberTheory/LegendreSymbol/ZModChar.lean | 113 | 115 | theorem χ₄_int_three_mod_four {n : ℤ} (hn : n % 4 = 3) : χ₄ n = -1 := by |
rw [χ₄_int_mod_four, hn]
rfl
|
import Mathlib.Analysis.Calculus.Deriv.Slope
import Mathlib.Analysis.Calculus.Deriv.Inv
#align_import analysis.calculus.dslope from "leanprover-community/mathlib"@"3bce8d800a6f2b8f63fe1e588fd76a9ff4adcebe"
open scoped Classical Topology Filter
open Function Set Filter
variable {𝕜 E : Type*} [NontriviallyNormedField 𝕜] [NormedAddCommGroup E] [NormedSpace 𝕜 E]
noncomputable def dslope (f : 𝕜 → E) (a : 𝕜) : 𝕜 → E :=
update (slope f a) a (deriv f a)
#align dslope dslope
@[simp]
theorem dslope_same (f : 𝕜 → E) (a : 𝕜) : dslope f a a = deriv f a :=
update_same _ _ _
#align dslope_same dslope_same
variable {f : 𝕜 → E} {a b : 𝕜} {s : Set 𝕜}
theorem dslope_of_ne (f : 𝕜 → E) (h : b ≠ a) : dslope f a b = slope f a b :=
update_noteq h _ _
#align dslope_of_ne dslope_of_ne
theorem ContinuousLinearMap.dslope_comp {F : Type*} [NormedAddCommGroup F] [NormedSpace 𝕜 F]
(f : E →L[𝕜] F) (g : 𝕜 → E) (a b : 𝕜) (H : a = b → DifferentiableAt 𝕜 g a) :
dslope (f ∘ g) a b = f (dslope g a b) := by
rcases eq_or_ne b a with (rfl | hne)
· simp only [dslope_same]
exact (f.hasFDerivAt.comp_hasDerivAt b (H rfl).hasDerivAt).deriv
· simpa only [dslope_of_ne _ hne] using f.toLinearMap.slope_comp g a b
#align continuous_linear_map.dslope_comp ContinuousLinearMap.dslope_comp
theorem eqOn_dslope_slope (f : 𝕜 → E) (a : 𝕜) : EqOn (dslope f a) (slope f a) {a}ᶜ := fun _ =>
dslope_of_ne f
#align eq_on_dslope_slope eqOn_dslope_slope
theorem dslope_eventuallyEq_slope_of_ne (f : 𝕜 → E) (h : b ≠ a) : dslope f a =ᶠ[𝓝 b] slope f a :=
(eqOn_dslope_slope f a).eventuallyEq_of_mem (isOpen_ne.mem_nhds h)
#align dslope_eventually_eq_slope_of_ne dslope_eventuallyEq_slope_of_ne
theorem dslope_eventuallyEq_slope_punctured_nhds (f : 𝕜 → E) : dslope f a =ᶠ[𝓝[≠] a] slope f a :=
(eqOn_dslope_slope f a).eventuallyEq_of_mem self_mem_nhdsWithin
#align dslope_eventually_eq_slope_punctured_nhds dslope_eventuallyEq_slope_punctured_nhds
@[simp]
theorem sub_smul_dslope (f : 𝕜 → E) (a b : 𝕜) : (b - a) • dslope f a b = f b - f a := by
rcases eq_or_ne b a with (rfl | hne) <;> simp [dslope_of_ne, *]
#align sub_smul_dslope sub_smul_dslope
theorem dslope_sub_smul_of_ne (f : 𝕜 → E) (h : b ≠ a) :
dslope (fun x => (x - a) • f x) a b = f b := by
rw [dslope_of_ne _ h, slope_sub_smul _ h.symm]
#align dslope_sub_smul_of_ne dslope_sub_smul_of_ne
theorem eqOn_dslope_sub_smul (f : 𝕜 → E) (a : 𝕜) :
EqOn (dslope (fun x => (x - a) • f x) a) f {a}ᶜ := fun _ => dslope_sub_smul_of_ne f
#align eq_on_dslope_sub_smul eqOn_dslope_sub_smul
theorem dslope_sub_smul [DecidableEq 𝕜] (f : 𝕜 → E) (a : 𝕜) :
dslope (fun x => (x - a) • f x) a = update f a (deriv (fun x => (x - a) • f x) a) :=
eq_update_iff.2 ⟨dslope_same _ _, eqOn_dslope_sub_smul f a⟩
#align dslope_sub_smul dslope_sub_smul
@[simp]
theorem continuousAt_dslope_same : ContinuousAt (dslope f a) a ↔ DifferentiableAt 𝕜 f a := by
simp only [dslope, continuousAt_update_same, ← hasDerivAt_deriv_iff, hasDerivAt_iff_tendsto_slope]
#align continuous_at_dslope_same continuousAt_dslope_same
theorem ContinuousWithinAt.of_dslope (h : ContinuousWithinAt (dslope f a) s b) :
ContinuousWithinAt f s b := by
have : ContinuousWithinAt (fun x => (x - a) • dslope f a x + f a) s b :=
((continuousWithinAt_id.sub continuousWithinAt_const).smul h).add continuousWithinAt_const
simpa only [sub_smul_dslope, sub_add_cancel] using this
#align continuous_within_at.of_dslope ContinuousWithinAt.of_dslope
theorem ContinuousAt.of_dslope (h : ContinuousAt (dslope f a) b) : ContinuousAt f b :=
(continuousWithinAt_univ _ _).1 h.continuousWithinAt.of_dslope
#align continuous_at.of_dslope ContinuousAt.of_dslope
theorem ContinuousOn.of_dslope (h : ContinuousOn (dslope f a) s) : ContinuousOn f s := fun x hx =>
(h x hx).of_dslope
#align continuous_on.of_dslope ContinuousOn.of_dslope
theorem continuousWithinAt_dslope_of_ne (h : b ≠ a) :
ContinuousWithinAt (dslope f a) s b ↔ ContinuousWithinAt f s b := by
refine ⟨ContinuousWithinAt.of_dslope, fun hc => ?_⟩
simp only [dslope, continuousWithinAt_update_of_ne h]
exact ((continuousWithinAt_id.sub continuousWithinAt_const).inv₀ (sub_ne_zero.2 h)).smul
(hc.sub continuousWithinAt_const)
#align continuous_within_at_dslope_of_ne continuousWithinAt_dslope_of_ne
theorem continuousAt_dslope_of_ne (h : b ≠ a) : ContinuousAt (dslope f a) b ↔ ContinuousAt f b := by
simp only [← continuousWithinAt_univ, continuousWithinAt_dslope_of_ne h]
#align continuous_at_dslope_of_ne continuousAt_dslope_of_ne
| Mathlib/Analysis/Calculus/Dslope.lean | 118 | 124 | theorem continuousOn_dslope (h : s ∈ 𝓝 a) :
ContinuousOn (dslope f a) s ↔ ContinuousOn f s ∧ DifferentiableAt 𝕜 f a := by |
refine ⟨fun hc => ⟨hc.of_dslope, continuousAt_dslope_same.1 <| hc.continuousAt h⟩, ?_⟩
rintro ⟨hc, hd⟩ x hx
rcases eq_or_ne x a with (rfl | hne)
exacts [(continuousAt_dslope_same.2 hd).continuousWithinAt,
(continuousWithinAt_dslope_of_ne hne).2 (hc x hx)]
|
import Mathlib.Order.Filter.EventuallyConst
import Mathlib.Order.PartialSups
import Mathlib.Algebra.Module.Submodule.IterateMapComap
import Mathlib.RingTheory.OrzechProperty
import Mathlib.RingTheory.Nilpotent.Lemmas
#align_import ring_theory.noetherian from "leanprover-community/mathlib"@"210657c4ea4a4a7b234392f70a3a2a83346dfa90"
open Set Filter Pointwise
-- Porting note: should this be renamed to `Noetherian`?
class IsNoetherian (R M) [Semiring R] [AddCommMonoid M] [Module R M] : Prop where
noetherian : ∀ s : Submodule R M, s.FG
#align is_noetherian IsNoetherian
attribute [inherit_doc IsNoetherian] IsNoetherian.noetherian
section
variable {R : Type*} {M : Type*} {P : Type*}
variable [Semiring R] [AddCommMonoid M] [AddCommMonoid P]
variable [Module R M] [Module R P]
open IsNoetherian
theorem isNoetherian_def : IsNoetherian R M ↔ ∀ s : Submodule R M, s.FG :=
⟨fun h => h.noetherian, IsNoetherian.mk⟩
#align is_noetherian_def isNoetherian_def
theorem isNoetherian_submodule {N : Submodule R M} :
IsNoetherian R N ↔ ∀ s : Submodule R M, s ≤ N → s.FG := by
refine ⟨fun ⟨hn⟩ => fun s hs =>
have : s ≤ LinearMap.range N.subtype := N.range_subtype.symm ▸ hs
Submodule.map_comap_eq_self this ▸ (hn _).map _,
fun h => ⟨fun s => ?_⟩⟩
have f := (Submodule.equivMapOfInjective N.subtype Subtype.val_injective s).symm
have h₁ := h (s.map N.subtype) (Submodule.map_subtype_le N s)
have h₂ : (⊤ : Submodule R (s.map N.subtype)).map f = ⊤ := by simp
have h₃ := ((Submodule.fg_top _).2 h₁).map (↑f : _ →ₗ[R] s)
exact (Submodule.fg_top _).1 (h₂ ▸ h₃)
#align is_noetherian_submodule isNoetherian_submodule
theorem isNoetherian_submodule_left {N : Submodule R M} :
IsNoetherian R N ↔ ∀ s : Submodule R M, (N ⊓ s).FG :=
isNoetherian_submodule.trans ⟨fun H _ => H _ inf_le_left, fun H _ hs => inf_of_le_right hs ▸ H _⟩
#align is_noetherian_submodule_left isNoetherian_submodule_left
theorem isNoetherian_submodule_right {N : Submodule R M} :
IsNoetherian R N ↔ ∀ s : Submodule R M, (s ⊓ N).FG :=
isNoetherian_submodule.trans ⟨fun H _ => H _ inf_le_right, fun H _ hs => inf_of_le_left hs ▸ H _⟩
#align is_noetherian_submodule_right isNoetherian_submodule_right
instance isNoetherian_submodule' [IsNoetherian R M] (N : Submodule R M) : IsNoetherian R N :=
isNoetherian_submodule.2 fun _ _ => IsNoetherian.noetherian _
#align is_noetherian_submodule' isNoetherian_submodule'
theorem isNoetherian_of_le {s t : Submodule R M} [ht : IsNoetherian R t] (h : s ≤ t) :
IsNoetherian R s :=
isNoetherian_submodule.mpr fun _ hs' => isNoetherian_submodule.mp ht _ (le_trans hs' h)
#align is_noetherian_of_le isNoetherian_of_le
variable (M)
theorem isNoetherian_of_surjective (f : M →ₗ[R] P) (hf : LinearMap.range f = ⊤) [IsNoetherian R M] :
IsNoetherian R P :=
⟨fun s =>
have : (s.comap f).map f = s := Submodule.map_comap_eq_self <| hf.symm ▸ le_top
this ▸ (noetherian _).map _⟩
#align is_noetherian_of_surjective isNoetherian_of_surjective
variable {M}
instance isNoetherian_quotient {R} [Ring R] {M} [AddCommGroup M] [Module R M]
(N : Submodule R M) [IsNoetherian R M] : IsNoetherian R (M ⧸ N) :=
isNoetherian_of_surjective _ _ (LinearMap.range_eq_top.mpr N.mkQ_surjective)
#align submodule.quotient.is_noetherian isNoetherian_quotient
@[deprecated (since := "2024-04-27"), nolint defLemma]
alias Submodule.Quotient.isNoetherian := isNoetherian_quotient
theorem isNoetherian_of_linearEquiv (f : M ≃ₗ[R] P) [IsNoetherian R M] : IsNoetherian R P :=
isNoetherian_of_surjective _ f.toLinearMap f.range
#align is_noetherian_of_linear_equiv isNoetherian_of_linearEquiv
theorem isNoetherian_top_iff : IsNoetherian R (⊤ : Submodule R M) ↔ IsNoetherian R M := by
constructor <;> intro h
· exact isNoetherian_of_linearEquiv (LinearEquiv.ofTop (⊤ : Submodule R M) rfl)
· exact isNoetherian_of_linearEquiv (LinearEquiv.ofTop (⊤ : Submodule R M) rfl).symm
#align is_noetherian_top_iff isNoetherian_top_iff
theorem isNoetherian_of_injective [IsNoetherian R P] (f : M →ₗ[R] P) (hf : Function.Injective f) :
IsNoetherian R M :=
isNoetherian_of_linearEquiv (LinearEquiv.ofInjective f hf).symm
#align is_noetherian_of_injective isNoetherian_of_injective
theorem fg_of_injective [IsNoetherian R P] {N : Submodule R M} (f : M →ₗ[R] P)
(hf : Function.Injective f) : N.FG :=
haveI := isNoetherian_of_injective f hf
IsNoetherian.noetherian N
#align fg_of_injective fg_of_injective
end
section
variable {R : Type*} {M : Type*} {P : Type*}
variable [Ring R] [AddCommGroup M] [AddCommGroup P]
variable [Module R M] [Module R P]
open IsNoetherian
theorem isNoetherian_of_ker_bot [IsNoetherian R P] (f : M →ₗ[R] P) (hf : LinearMap.ker f = ⊥) :
IsNoetherian R M :=
isNoetherian_of_linearEquiv (LinearEquiv.ofInjective f <| LinearMap.ker_eq_bot.mp hf).symm
#align is_noetherian_of_ker_bot isNoetherian_of_ker_bot
theorem fg_of_ker_bot [IsNoetherian R P] {N : Submodule R M} (f : M →ₗ[R] P)
(hf : LinearMap.ker f = ⊥) : N.FG :=
haveI := isNoetherian_of_ker_bot f hf
IsNoetherian.noetherian N
#align fg_of_ker_bot fg_of_ker_bot
instance isNoetherian_prod [IsNoetherian R M] [IsNoetherian R P] : IsNoetherian R (M × P) :=
⟨fun s =>
Submodule.fg_of_fg_map_of_fg_inf_ker (LinearMap.snd R M P) (noetherian _) <|
have : s ⊓ LinearMap.ker (LinearMap.snd R M P) ≤ LinearMap.range (LinearMap.inl R M P) :=
fun x ⟨_, hx2⟩ => ⟨x.1, Prod.ext rfl <| Eq.symm <| LinearMap.mem_ker.1 hx2⟩
Submodule.map_comap_eq_self this ▸ (noetherian _).map _⟩
#align is_noetherian_prod isNoetherian_prod
instance isNoetherian_pi {R ι : Type*} {M : ι → Type*}
[Ring R] [∀ i, AddCommGroup (M i)] [∀ i, Module R (M i)] [Finite ι]
[∀ i, IsNoetherian R (M i)] : IsNoetherian R (∀ i, M i) := by
cases nonempty_fintype ι
haveI := Classical.decEq ι
suffices on_finset : ∀ s : Finset ι, IsNoetherian R (∀ i : s, M i) by
let coe_e := Equiv.subtypeUnivEquiv <| @Finset.mem_univ ι _
letI : IsNoetherian R (∀ i : Finset.univ, M (coe_e i)) := on_finset Finset.univ
exact isNoetherian_of_linearEquiv (LinearEquiv.piCongrLeft R M coe_e)
intro s
induction' s using Finset.induction with a s has ih
· exact ⟨fun s => by
have : s = ⊥ := by simp only [eq_iff_true_of_subsingleton]
rw [this]
apply Submodule.fg_bot⟩
refine
@isNoetherian_of_linearEquiv R (M a × ((i : s) → M i)) _ _ _ _ _ _ ?_ <|
@isNoetherian_prod R (M a) _ _ _ _ _ _ _ ih
refine
{ toFun := fun f i =>
(Finset.mem_insert.1 i.2).by_cases
(fun h : i.1 = a => show M i.1 from Eq.recOn h.symm f.1)
(fun h : i.1 ∈ s => show M i.1 from f.2 ⟨i.1, h⟩),
invFun := fun f =>
(f ⟨a, Finset.mem_insert_self _ _⟩, fun i => f ⟨i.1, Finset.mem_insert_of_mem i.2⟩),
map_add' := ?_,
map_smul' := ?_
left_inv := ?_,
right_inv := ?_ }
· intro f g
ext i
unfold Or.by_cases
cases' i with i hi
rcases Finset.mem_insert.1 hi with (rfl | h)
· change _ = _ + _
simp only [dif_pos]
rfl
· change _ = _ + _
have : ¬i = a := by
rintro rfl
exact has h
simp only [dif_neg this, dif_pos h]
rfl
· intro c f
ext i
unfold Or.by_cases
cases' i with i hi
rcases Finset.mem_insert.1 hi with (rfl | h)
· dsimp
simp only [dif_pos]
· dsimp
have : ¬i = a := by
rintro rfl
exact has h
simp only [dif_neg this, dif_pos h]
· intro f
apply Prod.ext
· simp only [Or.by_cases, dif_pos]
· ext ⟨i, his⟩
have : ¬i = a := by
rintro rfl
exact has his
simp only [Or.by_cases, this, not_false_iff, dif_neg]
· intro f
ext ⟨i, hi⟩
rcases Finset.mem_insert.1 hi with (rfl | h)
· simp only [Or.by_cases, dif_pos]
· have : ¬i = a := by
rintro rfl
exact has h
simp only [Or.by_cases, dif_neg this, dif_pos h]
#align is_noetherian_pi isNoetherian_pi
instance isNoetherian_pi' {R ι M : Type*} [Ring R] [AddCommGroup M] [Module R M] [Finite ι]
[IsNoetherian R M] : IsNoetherian R (ι → M) :=
isNoetherian_pi
#align is_noetherian_pi' isNoetherian_pi'
end
open IsNoetherian Submodule Function
section
universe w
variable {R M P : Type*} {N : Type w} [Semiring R] [AddCommMonoid M] [Module R M] [AddCommMonoid N]
[Module R N] [AddCommMonoid P] [Module R P]
theorem isNoetherian_iff_wellFounded :
IsNoetherian R M ↔ WellFounded ((· > ·) : Submodule R M → Submodule R M → Prop) := by
have := (CompleteLattice.wellFounded_characterisations <| Submodule R M).out 0 3
-- Porting note: inlining this makes rw complain about it being a metavariable
rw [this]
exact
⟨fun ⟨h⟩ => fun k => (fg_iff_compact k).mp (h k), fun h =>
⟨fun k => (fg_iff_compact k).mpr (h k)⟩⟩
#align is_noetherian_iff_well_founded isNoetherian_iff_wellFounded
theorem isNoetherian_iff_fg_wellFounded :
IsNoetherian R M ↔
WellFounded
((· > ·) : { N : Submodule R M // N.FG } → { N : Submodule R M // N.FG } → Prop) := by
let α := { N : Submodule R M // N.FG }
constructor
· intro H
let f : α ↪o Submodule R M := OrderEmbedding.subtype _
exact OrderEmbedding.wellFounded f.dual (isNoetherian_iff_wellFounded.mp H)
· intro H
constructor
intro N
obtain ⟨⟨N₀, h₁⟩, e : N₀ ≤ N, h₂⟩ :=
WellFounded.has_min H { N' : α | N'.1 ≤ N } ⟨⟨⊥, Submodule.fg_bot⟩, @bot_le _ _ _ N⟩
convert h₁
refine (e.antisymm ?_).symm
by_contra h₃
obtain ⟨x, hx₁ : x ∈ N, hx₂ : x ∉ N₀⟩ := Set.not_subset.mp h₃
apply hx₂
rw [eq_of_le_of_not_lt (le_sup_right : N₀ ≤ _) (h₂
⟨_, Submodule.FG.sup ⟨{x}, by rw [Finset.coe_singleton]⟩ h₁⟩ <|
sup_le ((Submodule.span_singleton_le_iff_mem _ _).mpr hx₁) e)]
exact (le_sup_left : (R ∙ x) ≤ _) (Submodule.mem_span_singleton_self _)
#align is_noetherian_iff_fg_well_founded isNoetherian_iff_fg_wellFounded
variable (R M)
theorem wellFounded_submodule_gt (R M) [Semiring R] [AddCommMonoid M] [Module R M] :
∀ [IsNoetherian R M], WellFounded ((· > ·) : Submodule R M → Submodule R M → Prop) :=
isNoetherian_iff_wellFounded.mp ‹_›
#align well_founded_submodule_gt wellFounded_submodule_gt
variable {R M}
theorem set_has_maximal_iff_noetherian :
(∀ a : Set <| Submodule R M, a.Nonempty → ∃ M' ∈ a, ∀ I ∈ a, ¬M' < I) ↔ IsNoetherian R M := by
rw [isNoetherian_iff_wellFounded, WellFounded.wellFounded_iff_has_min]
#align set_has_maximal_iff_noetherian set_has_maximal_iff_noetherian
theorem monotone_stabilizes_iff_noetherian :
(∀ f : ℕ →o Submodule R M, ∃ n, ∀ m, n ≤ m → f n = f m) ↔ IsNoetherian R M := by
rw [isNoetherian_iff_wellFounded, WellFounded.monotone_chain_condition]
#align monotone_stabilizes_iff_noetherian monotone_stabilizes_iff_noetherian
theorem eventuallyConst_of_isNoetherian [IsNoetherian R M] (f : ℕ →o Submodule R M) :
atTop.EventuallyConst f := by
simp_rw [eventuallyConst_atTop, eq_comm]
exact (monotone_stabilizes_iff_noetherian.mpr inferInstance) f
theorem IsNoetherian.induction [IsNoetherian R M] {P : Submodule R M → Prop}
(hgt : ∀ I, (∀ J > I, P J) → P I) (I : Submodule R M) : P I :=
WellFounded.recursion (wellFounded_submodule_gt R M) I hgt
#align is_noetherian.induction IsNoetherian.induction
end
section
universe w
variable {R M P : Type*} {N : Type w} [Ring R] [AddCommGroup M] [Module R M] [AddCommGroup N]
[Module R N] [AddCommGroup P] [Module R P] [IsNoetherian R M]
lemma Submodule.finite_ne_bot_of_independent {ι : Type*} {N : ι → Submodule R M}
(h : CompleteLattice.Independent N) :
Set.Finite {i | N i ≠ ⊥} :=
CompleteLattice.WellFounded.finite_ne_bot_of_independent
(isNoetherian_iff_wellFounded.mp inferInstance) h
theorem LinearIndependent.finite_of_isNoetherian [Nontrivial R] {ι} {v : ι → M}
(hv : LinearIndependent R v) : Finite ι := by
have hwf := isNoetherian_iff_wellFounded.mp (by infer_instance : IsNoetherian R M)
refine CompleteLattice.WellFounded.finite_of_independent hwf hv.independent_span_singleton
fun i contra => ?_
apply hv.ne_zero i
have : v i ∈ R ∙ v i := Submodule.mem_span_singleton_self (v i)
rwa [contra, Submodule.mem_bot] at this
#align linear_independent.finite_of_is_noetherian LinearIndependent.finite_of_isNoetherian
theorem LinearIndependent.set_finite_of_isNoetherian [Nontrivial R] {s : Set M}
(hi : LinearIndependent R ((↑) : s → M)) : s.Finite :=
@Set.toFinite _ _ hi.finite_of_isNoetherian
#align linear_independent.set_finite_of_is_noetherian LinearIndependent.set_finite_of_isNoetherian
@[deprecated]
alias finite_of_linearIndependent := LinearIndependent.set_finite_of_isNoetherian
#align finite_of_linear_independent LinearIndependent.set_finite_of_isNoetherian
theorem isNoetherian_of_range_eq_ker [IsNoetherian R P]
(f : M →ₗ[R] N) (g : N →ₗ[R] P) (h : LinearMap.range f = LinearMap.ker g) :
IsNoetherian R N :=
isNoetherian_iff_wellFounded.2 <|
wellFounded_gt_exact_sequence
(wellFounded_submodule_gt R _) (wellFounded_submodule_gt R _)
(LinearMap.range f)
(Submodule.map (f.ker.liftQ f <| le_rfl))
(Submodule.comap (f.ker.liftQ f <| le_rfl))
(Submodule.comap g.rangeRestrict) (Submodule.map g.rangeRestrict)
(Submodule.gciMapComap <| LinearMap.ker_eq_bot.mp <|
Submodule.ker_liftQ_eq_bot _ _ _ (le_refl _))
(Submodule.giMapComap g.surjective_rangeRestrict)
(by simp [Submodule.map_comap_eq, inf_comm, Submodule.range_liftQ])
(by simp [Submodule.comap_map_eq, h])
#align is_noetherian_of_range_eq_ker isNoetherian_of_range_eq_ker
theorem LinearMap.eventually_disjoint_ker_pow_range_pow (f : M →ₗ[R] M) :
∀ᶠ n in atTop, Disjoint (LinearMap.ker (f ^ n)) (LinearMap.range (f ^ n)) := by
obtain ⟨n, hn : ∀ m, n ≤ m → LinearMap.ker (f ^ n) = LinearMap.ker (f ^ m)⟩ :=
monotone_stabilizes_iff_noetherian.mpr inferInstance f.iterateKer
refine eventually_atTop.mpr ⟨n, fun m hm ↦ disjoint_iff.mpr ?_⟩
rw [← hn _ hm, Submodule.eq_bot_iff]
rintro - ⟨hx, ⟨x, rfl⟩⟩
apply LinearMap.pow_map_zero_of_le hm
replace hx : x ∈ LinearMap.ker (f ^ (n + m)) := by
simpa [f.pow_apply n, f.pow_apply m, ← f.pow_apply (n + m), ← iterate_add_apply] using hx
rwa [← hn _ (n.le_add_right m)] at hx
#align is_noetherian.exists_endomorphism_iterate_ker_inf_range_eq_bot LinearMap.eventually_disjoint_ker_pow_range_pow
lemma LinearMap.eventually_iSup_ker_pow_eq (f : M →ₗ[R] M) :
∀ᶠ n in atTop, ⨆ m, LinearMap.ker (f ^ m) = LinearMap.ker (f ^ n) := by
obtain ⟨n, hn : ∀ m, n ≤ m → ker (f ^ n) = ker (f ^ m)⟩ :=
monotone_stabilizes_iff_noetherian.mpr inferInstance f.iterateKer
refine eventually_atTop.mpr ⟨n, fun m hm ↦ ?_⟩
refine le_antisymm (iSup_le fun l ↦ ?_) (le_iSup (fun i ↦ LinearMap.ker (f ^ i)) m)
rcases le_or_lt m l with h | h
· rw [← hn _ (hm.trans h), hn _ hm]
· exact f.iterateKer.monotone h.le
theorem IsNoetherian.injective_of_surjective_of_injective (i f : N →ₗ[R] M)
(hi : Injective i) (hf : Surjective f) : Injective f := by
haveI := isNoetherian_of_injective i hi
obtain ⟨n, H⟩ := monotone_stabilizes_iff_noetherian.2 ‹_›
⟨_, monotone_nat_of_le_succ <| f.iterateMapComap_le_succ i ⊥ (by simp)⟩
exact LinearMap.ker_eq_bot.1 <| bot_unique <|
f.ker_le_of_iterateMapComap_eq_succ i ⊥ n (H _ (Nat.le_succ _)) hf hi
theorem IsNoetherian.injective_of_surjective_of_submodule
{N : Submodule R M} (f : N →ₗ[R] M) (hf : Surjective f) : Injective f :=
IsNoetherian.injective_of_surjective_of_injective N.subtype f N.injective_subtype hf
theorem IsNoetherian.injective_of_surjective_endomorphism (f : M →ₗ[R] M)
(s : Surjective f) : Injective f :=
IsNoetherian.injective_of_surjective_of_injective _ f (LinearEquiv.refl _ _).injective s
#align is_noetherian.injective_of_surjective_endomorphism IsNoetherian.injective_of_surjective_endomorphism
theorem IsNoetherian.bijective_of_surjective_endomorphism (f : M →ₗ[R] M)
(s : Surjective f) : Bijective f :=
⟨IsNoetherian.injective_of_surjective_endomorphism f s, s⟩
#align is_noetherian.bijective_of_surjective_endomorphism IsNoetherian.bijective_of_surjective_endomorphism
theorem IsNoetherian.disjoint_partialSups_eventually_bot
(f : ℕ → Submodule R M) (h : ∀ n, Disjoint (partialSups f n) (f (n + 1))) :
∃ n : ℕ, ∀ m, n ≤ m → f m = ⊥ := by
-- A little off-by-one cleanup first:
suffices t : ∃ n : ℕ, ∀ m, n ≤ m → f (m + 1) = ⊥ by
obtain ⟨n, w⟩ := t
use n + 1
rintro (_ | m) p
· cases p
· apply w
exact Nat.succ_le_succ_iff.mp p
obtain ⟨n, w⟩ := monotone_stabilizes_iff_noetherian.mpr inferInstance (partialSups f)
exact
⟨n, fun m p =>
(h m).eq_bot_of_ge <| sup_eq_left.1 <| (w (m + 1) <| le_add_right p).symm.trans <| w m p⟩
#align is_noetherian.disjoint_partial_sups_eventually_bot IsNoetherian.disjoint_partialSups_eventually_bot
theorem IsNoetherian.subsingleton_of_prod_injective (f : M × N →ₗ[R] M)
(i : Injective f) : Subsingleton N := .intro fun x y ↦ by
have h := IsNoetherian.injective_of_surjective_of_injective f _ i LinearMap.fst_surjective
simpa using h (show LinearMap.fst R M N (0, x) = LinearMap.fst R M N (0, y) from rfl)
@[simps!]
def IsNoetherian.equivPUnitOfProdInjective (f : M × N →ₗ[R] M)
(i : Injective f) : N ≃ₗ[R] PUnit.{w + 1} :=
haveI := IsNoetherian.subsingleton_of_prod_injective f i
.ofSubsingleton _ _
#align is_noetherian.equiv_punit_of_prod_injective IsNoetherian.equivPUnitOfProdInjective
end
abbrev IsNoetherianRing (R) [Semiring R] :=
IsNoetherian R R
#align is_noetherian_ring IsNoetherianRing
theorem isNoetherianRing_iff {R} [Semiring R] : IsNoetherianRing R ↔ IsNoetherian R R :=
Iff.rfl
#align is_noetherian_ring_iff isNoetherianRing_iff
theorem isNoetherianRing_iff_ideal_fg (R : Type*) [Semiring R] :
IsNoetherianRing R ↔ ∀ I : Ideal R, I.FG :=
isNoetherianRing_iff.trans isNoetherian_def
#align is_noetherian_ring_iff_ideal_fg isNoetherianRing_iff_ideal_fg
-- see Note [lower instance priority]
instance (priority := 80) isNoetherian_of_finite (R M) [Finite M] [Semiring R] [AddCommMonoid M]
[Module R M] : IsNoetherian R M :=
⟨fun s => ⟨(s : Set M).toFinite.toFinset, by rw [Set.Finite.coe_toFinset, Submodule.span_eq]⟩⟩
#align is_noetherian_of_finite isNoetherian_of_finite
-- see Note [lower instance priority]
instance (priority := 100) isNoetherian_of_subsingleton (R M) [Subsingleton R] [Semiring R]
[AddCommMonoid M] [Module R M] : IsNoetherian R M :=
haveI := Module.subsingleton R M
isNoetherian_of_finite R M
#align is_noetherian_of_subsingleton isNoetherian_of_subsingleton
| Mathlib/RingTheory/Noetherian.lean | 562 | 565 | theorem isNoetherian_of_submodule_of_noetherian (R M) [Semiring R] [AddCommMonoid M] [Module R M]
(N : Submodule R M) (h : IsNoetherian R M) : IsNoetherian R N := by |
rw [isNoetherian_iff_wellFounded] at h ⊢
exact OrderEmbedding.wellFounded (Submodule.MapSubtype.orderEmbedding N).dual h
|
import Mathlib.Analysis.InnerProductSpace.Basic
import Mathlib.Analysis.SpecialFunctions.Trigonometric.Inverse
#align_import geometry.euclidean.angle.unoriented.basic from "leanprover-community/mathlib"@"46b633fd842bef9469441c0209906f6dddd2b4f5"
assert_not_exists HasFDerivAt
assert_not_exists ConformalAt
noncomputable section
open Real Set
open Real
open RealInnerProductSpace
namespace InnerProductGeometry
variable {V : Type*} [NormedAddCommGroup V] [InnerProductSpace ℝ V] {x y : V}
def angle (x y : V) : ℝ :=
Real.arccos (⟪x, y⟫ / (‖x‖ * ‖y‖))
#align inner_product_geometry.angle InnerProductGeometry.angle
theorem continuousAt_angle {x : V × V} (hx1 : x.1 ≠ 0) (hx2 : x.2 ≠ 0) :
ContinuousAt (fun y : V × V => angle y.1 y.2) x :=
Real.continuous_arccos.continuousAt.comp <|
continuous_inner.continuousAt.div
((continuous_norm.comp continuous_fst).mul (continuous_norm.comp continuous_snd)).continuousAt
(by simp [hx1, hx2])
#align inner_product_geometry.continuous_at_angle InnerProductGeometry.continuousAt_angle
theorem angle_smul_smul {c : ℝ} (hc : c ≠ 0) (x y : V) : angle (c • x) (c • y) = angle x y := by
have : c * c ≠ 0 := mul_ne_zero hc hc
rw [angle, angle, real_inner_smul_left, inner_smul_right, norm_smul, norm_smul, Real.norm_eq_abs,
mul_mul_mul_comm _ ‖x‖, abs_mul_abs_self, ← mul_assoc c c, mul_div_mul_left _ _ this]
#align inner_product_geometry.angle_smul_smul InnerProductGeometry.angle_smul_smul
@[simp]
theorem _root_.LinearIsometry.angle_map {E F : Type*} [NormedAddCommGroup E] [NormedAddCommGroup F]
[InnerProductSpace ℝ E] [InnerProductSpace ℝ F] (f : E →ₗᵢ[ℝ] F) (u v : E) :
angle (f u) (f v) = angle u v := by
rw [angle, angle, f.inner_map_map, f.norm_map, f.norm_map]
#align linear_isometry.angle_map LinearIsometry.angle_map
@[simp, norm_cast]
theorem _root_.Submodule.angle_coe {s : Submodule ℝ V} (x y : s) :
angle (x : V) (y : V) = angle x y :=
s.subtypeₗᵢ.angle_map x y
#align submodule.angle_coe Submodule.angle_coe
theorem cos_angle (x y : V) : Real.cos (angle x y) = ⟪x, y⟫ / (‖x‖ * ‖y‖) :=
Real.cos_arccos (abs_le.mp (abs_real_inner_div_norm_mul_norm_le_one x y)).1
(abs_le.mp (abs_real_inner_div_norm_mul_norm_le_one x y)).2
#align inner_product_geometry.cos_angle InnerProductGeometry.cos_angle
theorem angle_comm (x y : V) : angle x y = angle y x := by
unfold angle
rw [real_inner_comm, mul_comm]
#align inner_product_geometry.angle_comm InnerProductGeometry.angle_comm
@[simp]
theorem angle_neg_neg (x y : V) : angle (-x) (-y) = angle x y := by
unfold angle
rw [inner_neg_neg, norm_neg, norm_neg]
#align inner_product_geometry.angle_neg_neg InnerProductGeometry.angle_neg_neg
theorem angle_nonneg (x y : V) : 0 ≤ angle x y :=
Real.arccos_nonneg _
#align inner_product_geometry.angle_nonneg InnerProductGeometry.angle_nonneg
theorem angle_le_pi (x y : V) : angle x y ≤ π :=
Real.arccos_le_pi _
#align inner_product_geometry.angle_le_pi InnerProductGeometry.angle_le_pi
theorem angle_neg_right (x y : V) : angle x (-y) = π - angle x y := by
unfold angle
rw [← Real.arccos_neg, norm_neg, inner_neg_right, neg_div]
#align inner_product_geometry.angle_neg_right InnerProductGeometry.angle_neg_right
theorem angle_neg_left (x y : V) : angle (-x) y = π - angle x y := by
rw [← angle_neg_neg, neg_neg, angle_neg_right]
#align inner_product_geometry.angle_neg_left InnerProductGeometry.angle_neg_left
proof_wanted angle_triangle (x y z : V) : angle x z ≤ angle x y + angle y z
@[simp]
theorem angle_zero_left (x : V) : angle 0 x = π / 2 := by
unfold angle
rw [inner_zero_left, zero_div, Real.arccos_zero]
#align inner_product_geometry.angle_zero_left InnerProductGeometry.angle_zero_left
@[simp]
theorem angle_zero_right (x : V) : angle x 0 = π / 2 := by
unfold angle
rw [inner_zero_right, zero_div, Real.arccos_zero]
#align inner_product_geometry.angle_zero_right InnerProductGeometry.angle_zero_right
@[simp]
theorem angle_self {x : V} (hx : x ≠ 0) : angle x x = 0 := by
unfold angle
rw [← real_inner_self_eq_norm_mul_norm, div_self (inner_self_ne_zero.2 hx : ⟪x, x⟫ ≠ 0),
Real.arccos_one]
#align inner_product_geometry.angle_self InnerProductGeometry.angle_self
@[simp]
theorem angle_self_neg_of_nonzero {x : V} (hx : x ≠ 0) : angle x (-x) = π := by
rw [angle_neg_right, angle_self hx, sub_zero]
#align inner_product_geometry.angle_self_neg_of_nonzero InnerProductGeometry.angle_self_neg_of_nonzero
@[simp]
| Mathlib/Geometry/Euclidean/Angle/Unoriented/Basic.lean | 149 | 150 | theorem angle_neg_self_of_nonzero {x : V} (hx : x ≠ 0) : angle (-x) x = π := by |
rw [angle_comm, angle_self_neg_of_nonzero hx]
|
import Mathlib.Algebra.Polynomial.Roots
import Mathlib.Analysis.Asymptotics.AsymptoticEquivalent
import Mathlib.Analysis.Asymptotics.SpecificAsymptotics
#align_import analysis.special_functions.polynomials from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982"
open Filter Finset Asymptotics
open Asymptotics Polynomial Topology
namespace Polynomial
variable {𝕜 : Type*} [NormedLinearOrderedField 𝕜] (P Q : 𝕜[X])
theorem eventually_no_roots (hP : P ≠ 0) : ∀ᶠ x in atTop, ¬P.IsRoot x :=
atTop_le_cofinite <| (finite_setOf_isRoot hP).compl_mem_cofinite
#align polynomial.eventually_no_roots Polynomial.eventually_no_roots
variable [OrderTopology 𝕜]
section PolynomialAtTop
theorem isEquivalent_atTop_lead :
(fun x => eval x P) ~[atTop] fun x => P.leadingCoeff * x ^ P.natDegree := by
by_cases h : P = 0
· simp [h, IsEquivalent.refl]
· simp only [Polynomial.eval_eq_sum_range, sum_range_succ]
exact
IsLittleO.add_isEquivalent
(IsLittleO.sum fun i hi =>
IsLittleO.const_mul_left
((IsLittleO.const_mul_right fun hz => h <| leadingCoeff_eq_zero.mp hz) <|
isLittleO_pow_pow_atTop_of_lt (mem_range.mp hi))
_)
IsEquivalent.refl
#align polynomial.is_equivalent_at_top_lead Polynomial.isEquivalent_atTop_lead
theorem tendsto_atTop_of_leadingCoeff_nonneg (hdeg : 0 < P.degree) (hnng : 0 ≤ P.leadingCoeff) :
Tendsto (fun x => eval x P) atTop atTop :=
P.isEquivalent_atTop_lead.symm.tendsto_atTop <|
tendsto_const_mul_pow_atTop (natDegree_pos_iff_degree_pos.2 hdeg).ne' <|
hnng.lt_of_ne' <| leadingCoeff_ne_zero.mpr <| ne_zero_of_degree_gt hdeg
#align polynomial.tendsto_at_top_of_leading_coeff_nonneg Polynomial.tendsto_atTop_of_leadingCoeff_nonneg
theorem tendsto_atTop_iff_leadingCoeff_nonneg :
Tendsto (fun x => eval x P) atTop atTop ↔ 0 < P.degree ∧ 0 ≤ P.leadingCoeff := by
refine ⟨fun h => ?_, fun h => tendsto_atTop_of_leadingCoeff_nonneg P h.1 h.2⟩
have : Tendsto (fun x => P.leadingCoeff * x ^ P.natDegree) atTop atTop :=
(isEquivalent_atTop_lead P).tendsto_atTop h
rw [tendsto_const_mul_pow_atTop_iff, ← pos_iff_ne_zero, natDegree_pos_iff_degree_pos] at this
exact ⟨this.1, this.2.le⟩
#align polynomial.tendsto_at_top_iff_leading_coeff_nonneg Polynomial.tendsto_atTop_iff_leadingCoeff_nonneg
| Mathlib/Analysis/SpecialFunctions/Polynomials.lean | 73 | 76 | theorem tendsto_atBot_iff_leadingCoeff_nonpos :
Tendsto (fun x => eval x P) atTop atBot ↔ 0 < P.degree ∧ P.leadingCoeff ≤ 0 := by |
simp only [← tendsto_neg_atTop_iff, ← eval_neg, tendsto_atTop_iff_leadingCoeff_nonneg,
degree_neg, leadingCoeff_neg, neg_nonneg]
|
import Mathlib.Algebra.BigOperators.Group.List
import Mathlib.Data.Vector.Defs
import Mathlib.Data.List.Nodup
import Mathlib.Data.List.OfFn
import Mathlib.Data.List.InsertNth
import Mathlib.Control.Applicative
import Mathlib.Control.Traversable.Basic
#align_import data.vector.basic from "leanprover-community/mathlib"@"f694c7dead66f5d4c80f446c796a5aad14707f0e"
set_option autoImplicit true
universe u
variable {n : ℕ}
namespace Vector
variable {α : Type*}
@[inherit_doc]
infixr:67 " ::ᵥ " => Vector.cons
attribute [simp] head_cons tail_cons
instance [Inhabited α] : Inhabited (Vector α n) :=
⟨ofFn default⟩
theorem toList_injective : Function.Injective (@toList α n) :=
Subtype.val_injective
#align vector.to_list_injective Vector.toList_injective
@[ext]
theorem ext : ∀ {v w : Vector α n} (_ : ∀ m : Fin n, Vector.get v m = Vector.get w m), v = w
| ⟨v, hv⟩, ⟨w, hw⟩, h =>
Subtype.eq (List.ext_get (by rw [hv, hw]) fun m hm _ => h ⟨m, hv ▸ hm⟩)
#align vector.ext Vector.ext
instance zero_subsingleton : Subsingleton (Vector α 0) :=
⟨fun _ _ => Vector.ext fun m => Fin.elim0 m⟩
#align vector.zero_subsingleton Vector.zero_subsingleton
@[simp]
theorem cons_val (a : α) : ∀ v : Vector α n, (a ::ᵥ v).val = a :: v.val
| ⟨_, _⟩ => rfl
#align vector.cons_val Vector.cons_val
#align vector.cons_head Vector.head_cons
#align vector.cons_tail Vector.tail_cons
theorem eq_cons_iff (a : α) (v : Vector α n.succ) (v' : Vector α n) :
v = a ::ᵥ v' ↔ v.head = a ∧ v.tail = v' :=
⟨fun h => h.symm ▸ ⟨head_cons a v', tail_cons a v'⟩, fun h =>
_root_.trans (cons_head_tail v).symm (by rw [h.1, h.2])⟩
#align vector.eq_cons_iff Vector.eq_cons_iff
theorem ne_cons_iff (a : α) (v : Vector α n.succ) (v' : Vector α n) :
v ≠ a ::ᵥ v' ↔ v.head ≠ a ∨ v.tail ≠ v' := by rw [Ne, eq_cons_iff a v v', not_and_or]
#align vector.ne_cons_iff Vector.ne_cons_iff
theorem exists_eq_cons (v : Vector α n.succ) : ∃ (a : α) (as : Vector α n), v = a ::ᵥ as :=
⟨v.head, v.tail, (eq_cons_iff v.head v v.tail).2 ⟨rfl, rfl⟩⟩
#align vector.exists_eq_cons Vector.exists_eq_cons
@[simp]
theorem toList_ofFn : ∀ {n} (f : Fin n → α), toList (ofFn f) = List.ofFn f
| 0, f => by rw [ofFn, List.ofFn_zero, toList, nil]
| n + 1, f => by rw [ofFn, List.ofFn_succ, toList_cons, toList_ofFn]
#align vector.to_list_of_fn Vector.toList_ofFn
@[simp]
theorem mk_toList : ∀ (v : Vector α n) (h), (⟨toList v, h⟩ : Vector α n) = v
| ⟨_, _⟩, _ => rfl
#align vector.mk_to_list Vector.mk_toList
@[simp] theorem length_val (v : Vector α n) : v.val.length = n := v.2
-- Porting note: not used in mathlib and coercions done differently in Lean 4
-- @[simp]
-- theorem length_coe (v : Vector α n) :
-- ((coe : { l : List α // l.length = n } → List α) v).length = n :=
-- v.2
#noalign vector.length_coe
@[simp]
theorem toList_map {β : Type*} (v : Vector α n) (f : α → β) :
(v.map f).toList = v.toList.map f := by cases v; rfl
#align vector.to_list_map Vector.toList_map
@[simp]
theorem head_map {β : Type*} (v : Vector α (n + 1)) (f : α → β) : (v.map f).head = f v.head := by
obtain ⟨a, v', h⟩ := Vector.exists_eq_cons v
rw [h, map_cons, head_cons, head_cons]
#align vector.head_map Vector.head_map
@[simp]
theorem tail_map {β : Type*} (v : Vector α (n + 1)) (f : α → β) :
(v.map f).tail = v.tail.map f := by
obtain ⟨a, v', h⟩ := Vector.exists_eq_cons v
rw [h, map_cons, tail_cons, tail_cons]
#align vector.tail_map Vector.tail_map
theorem get_eq_get (v : Vector α n) (i : Fin n) :
v.get i = v.toList.get (Fin.cast v.toList_length.symm i) :=
rfl
#align vector.nth_eq_nth_le Vector.get_eq_getₓ
@[simp]
theorem get_replicate (a : α) (i : Fin n) : (Vector.replicate n a).get i = a := by
apply List.get_replicate
#align vector.nth_repeat Vector.get_replicate
@[simp]
theorem get_map {β : Type*} (v : Vector α n) (f : α → β) (i : Fin n) :
(v.map f).get i = f (v.get i) := by
cases v; simp [Vector.map, get_eq_get]; rfl
#align vector.nth_map Vector.get_map
@[simp]
theorem map₂_nil (f : α → β → γ) : Vector.map₂ f nil nil = nil :=
rfl
@[simp]
theorem map₂_cons (hd₁ : α) (tl₁ : Vector α n) (hd₂ : β) (tl₂ : Vector β n) (f : α → β → γ) :
Vector.map₂ f (hd₁ ::ᵥ tl₁) (hd₂ ::ᵥ tl₂) = f hd₁ hd₂ ::ᵥ (Vector.map₂ f tl₁ tl₂) :=
rfl
@[simp]
theorem get_ofFn {n} (f : Fin n → α) (i) : get (ofFn f) i = f i := by
conv_rhs => erw [← List.get_ofFn f ⟨i, by simp⟩]
simp only [get_eq_get]
congr <;> simp [Fin.heq_ext_iff]
#align vector.nth_of_fn Vector.get_ofFn
@[simp]
theorem ofFn_get (v : Vector α n) : ofFn (get v) = v := by
rcases v with ⟨l, rfl⟩
apply toList_injective
dsimp
simpa only [toList_ofFn] using List.ofFn_get _
#align vector.of_fn_nth Vector.ofFn_get
def _root_.Equiv.vectorEquivFin (α : Type*) (n : ℕ) : Vector α n ≃ (Fin n → α) :=
⟨Vector.get, Vector.ofFn, Vector.ofFn_get, fun f => funext <| Vector.get_ofFn f⟩
#align equiv.vector_equiv_fin Equiv.vectorEquivFin
theorem get_tail (x : Vector α n) (i) : x.tail.get i = x.get ⟨i.1 + 1, by omega⟩ := by
cases' i with i ih; dsimp
rcases x with ⟨_ | _, h⟩ <;> try rfl
rw [List.length] at h
rw [← h] at ih
contradiction
#align vector.nth_tail Vector.get_tail
@[simp]
theorem get_tail_succ : ∀ (v : Vector α n.succ) (i : Fin n), get (tail v) i = get v i.succ
| ⟨a :: l, e⟩, ⟨i, h⟩ => by simp [get_eq_get]; rfl
#align vector.nth_tail_succ Vector.get_tail_succ
@[simp]
theorem tail_val : ∀ v : Vector α n.succ, v.tail.val = v.val.tail
| ⟨_ :: _, _⟩ => rfl
#align vector.tail_val Vector.tail_val
@[simp]
theorem tail_nil : (@nil α).tail = nil :=
rfl
#align vector.tail_nil Vector.tail_nil
@[simp]
theorem singleton_tail : ∀ (v : Vector α 1), v.tail = Vector.nil
| ⟨[_], _⟩ => rfl
#align vector.singleton_tail Vector.singleton_tail
@[simp]
theorem tail_ofFn {n : ℕ} (f : Fin n.succ → α) : tail (ofFn f) = ofFn fun i => f i.succ :=
(ofFn_get _).symm.trans <| by
congr
funext i
rw [get_tail, get_ofFn]
rfl
#align vector.tail_of_fn Vector.tail_ofFn
@[simp]
theorem toList_empty (v : Vector α 0) : v.toList = [] :=
List.length_eq_zero.mp v.2
#align vector.to_list_empty Vector.toList_empty
@[simp]
theorem toList_singleton (v : Vector α 1) : v.toList = [v.head] := by
rw [← v.cons_head_tail]
simp only [toList_cons, toList_nil, head_cons, eq_self_iff_true, and_self_iff, singleton_tail]
#align vector.to_list_singleton Vector.toList_singleton
@[simp]
theorem empty_toList_eq_ff (v : Vector α (n + 1)) : v.toList.isEmpty = false :=
match v with
| ⟨_ :: _, _⟩ => rfl
#align vector.empty_to_list_eq_ff Vector.empty_toList_eq_ff
theorem not_empty_toList (v : Vector α (n + 1)) : ¬v.toList.isEmpty := by
simp only [empty_toList_eq_ff, Bool.coe_sort_false, not_false_iff]
#align vector.not_empty_to_list Vector.not_empty_toList
@[simp]
theorem map_id {n : ℕ} (v : Vector α n) : Vector.map id v = v :=
Vector.eq _ _ (by simp only [List.map_id, Vector.toList_map])
#align vector.map_id Vector.map_id
theorem nodup_iff_injective_get {v : Vector α n} : v.toList.Nodup ↔ Function.Injective v.get := by
cases' v with l hl
subst hl
exact List.nodup_iff_injective_get
#align vector.nodup_iff_nth_inj Vector.nodup_iff_injective_get
theorem head?_toList : ∀ v : Vector α n.succ, (toList v).head? = some (head v)
| ⟨_ :: _, _⟩ => rfl
#align vector.head'_to_list Vector.head?_toList
def reverse (v : Vector α n) : Vector α n :=
⟨v.toList.reverse, by simp⟩
#align vector.reverse Vector.reverse
theorem toList_reverse {v : Vector α n} : v.reverse.toList = v.toList.reverse :=
rfl
#align vector.to_list_reverse Vector.toList_reverse
@[simp]
theorem reverse_reverse {v : Vector α n} : v.reverse.reverse = v := by
cases v
simp [Vector.reverse]
#align vector.reverse_reverse Vector.reverse_reverse
@[simp]
theorem get_zero : ∀ v : Vector α n.succ, get v 0 = head v
| ⟨_ :: _, _⟩ => rfl
#align vector.nth_zero Vector.get_zero
@[simp]
theorem head_ofFn {n : ℕ} (f : Fin n.succ → α) : head (ofFn f) = f 0 := by
rw [← get_zero, get_ofFn]
#align vector.head_of_fn Vector.head_ofFn
--@[simp] Porting note (#10618): simp can prove it
| Mathlib/Data/Vector/Basic.lean | 269 | 269 | theorem get_cons_zero (a : α) (v : Vector α n) : get (a ::ᵥ v) 0 = a := by | simp [get_zero]
|
import Mathlib.Data.Finsupp.Basic
import Mathlib.Data.Finsupp.Order
#align_import data.finsupp.multiset from "leanprover-community/mathlib"@"59694bd07f0a39c5beccba34bd9f413a160782bf"
open Finset
variable {α β ι : Type*}
namespace Finsupp
def toMultiset : (α →₀ ℕ) →+ Multiset α where
toFun f := Finsupp.sum f fun a n => n • {a}
-- Porting note: times out if h is not specified
map_add' _f _g := sum_add_index' (h := fun a n => n • ({a} : Multiset α))
(fun _ ↦ zero_nsmul _) (fun _ ↦ add_nsmul _)
map_zero' := sum_zero_index
theorem toMultiset_zero : toMultiset (0 : α →₀ ℕ) = 0 :=
rfl
#align finsupp.to_multiset_zero Finsupp.toMultiset_zero
theorem toMultiset_add (m n : α →₀ ℕ) : toMultiset (m + n) = toMultiset m + toMultiset n :=
toMultiset.map_add m n
#align finsupp.to_multiset_add Finsupp.toMultiset_add
theorem toMultiset_apply (f : α →₀ ℕ) : toMultiset f = f.sum fun a n => n • {a} :=
rfl
#align finsupp.to_multiset_apply Finsupp.toMultiset_apply
@[simp]
theorem toMultiset_single (a : α) (n : ℕ) : toMultiset (single a n) = n • {a} := by
rw [toMultiset_apply, sum_single_index]; apply zero_nsmul
#align finsupp.to_multiset_single Finsupp.toMultiset_single
theorem toMultiset_sum {f : ι → α →₀ ℕ} (s : Finset ι) :
Finsupp.toMultiset (∑ i ∈ s, f i) = ∑ i ∈ s, Finsupp.toMultiset (f i) :=
map_sum Finsupp.toMultiset _ _
#align finsupp.to_multiset_sum Finsupp.toMultiset_sum
theorem toMultiset_sum_single (s : Finset ι) (n : ℕ) :
Finsupp.toMultiset (∑ i ∈ s, single i n) = n • s.val := by
simp_rw [toMultiset_sum, Finsupp.toMultiset_single, sum_nsmul, sum_multiset_singleton]
#align finsupp.to_multiset_sum_single Finsupp.toMultiset_sum_single
@[simp]
| Mathlib/Data/Finsupp/Multiset.lean | 67 | 68 | theorem card_toMultiset (f : α →₀ ℕ) : Multiset.card (toMultiset f) = f.sum fun _ => id := by |
simp [toMultiset_apply, map_finsupp_sum, Function.id_def]
|
import Mathlib.Order.RelClasses
#align_import data.sigma.lex from "leanprover-community/mathlib"@"41cf0cc2f528dd40a8f2db167ea4fb37b8fde7f3"
namespace Sigma
variable {ι : Type*} {α : ι → Type*} {r r₁ r₂ : ι → ι → Prop} {s s₁ s₂ : ∀ i, α i → α i → Prop}
{a b : Σ i, α i}
inductive Lex (r : ι → ι → Prop) (s : ∀ i, α i → α i → Prop) : ∀ _ _ : Σ i, α i, Prop
| left {i j : ι} (a : α i) (b : α j) : r i j → Lex r s ⟨i, a⟩ ⟨j, b⟩
| right {i : ι} (a b : α i) : s i a b → Lex r s ⟨i, a⟩ ⟨i, b⟩
#align sigma.lex Sigma.Lex
theorem lex_iff : Lex r s a b ↔ r a.1 b.1 ∨ ∃ h : a.1 = b.1, s b.1 (h.rec a.2) b.2 := by
constructor
· rintro (⟨a, b, hij⟩ | ⟨a, b, hab⟩)
· exact Or.inl hij
· exact Or.inr ⟨rfl, hab⟩
· obtain ⟨i, a⟩ := a
obtain ⟨j, b⟩ := b
dsimp only
rintro (h | ⟨rfl, h⟩)
· exact Lex.left _ _ h
· exact Lex.right _ _ h
#align sigma.lex_iff Sigma.lex_iff
instance Lex.decidable (r : ι → ι → Prop) (s : ∀ i, α i → α i → Prop) [DecidableEq ι]
[DecidableRel r] [∀ i, DecidableRel (s i)] : DecidableRel (Lex r s) := fun _ _ =>
decidable_of_decidable_of_iff lex_iff.symm
#align sigma.lex.decidable Sigma.Lex.decidable
theorem Lex.mono (hr : ∀ a b, r₁ a b → r₂ a b) (hs : ∀ i a b, s₁ i a b → s₂ i a b) {a b : Σ i, α i}
(h : Lex r₁ s₁ a b) : Lex r₂ s₂ a b := by
obtain ⟨a, b, hij⟩ | ⟨a, b, hab⟩ := h
· exact Lex.left _ _ (hr _ _ hij)
· exact Lex.right _ _ (hs _ _ _ hab)
#align sigma.lex.mono Sigma.Lex.mono
theorem Lex.mono_left (hr : ∀ a b, r₁ a b → r₂ a b) {a b : Σ i, α i} (h : Lex r₁ s a b) :
Lex r₂ s a b :=
h.mono hr fun _ _ _ => id
#align sigma.lex.mono_left Sigma.Lex.mono_left
theorem Lex.mono_right (hs : ∀ i a b, s₁ i a b → s₂ i a b) {a b : Σ i, α i} (h : Lex r s₁ a b) :
Lex r s₂ a b :=
h.mono (fun _ _ => id) hs
#align sigma.lex.mono_right Sigma.Lex.mono_right
| Mathlib/Data/Sigma/Lex.lean | 80 | 83 | theorem lex_swap : Lex (Function.swap r) s a b ↔ Lex r (fun i => Function.swap (s i)) b a := by |
constructor <;>
· rintro (⟨a, b, h⟩ | ⟨a, b, h⟩)
exacts [Lex.left _ _ h, Lex.right _ _ h]
|
import Mathlib.Probability.Variance
import Mathlib.MeasureTheory.Function.UniformIntegrable
#align_import probability.ident_distrib from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982"
open MeasureTheory Filter Finset
noncomputable section
open scoped Topology MeasureTheory ENNReal NNReal
variable {α β γ δ : Type*} [MeasurableSpace α] [MeasurableSpace β] [MeasurableSpace γ]
[MeasurableSpace δ]
namespace ProbabilityTheory
structure IdentDistrib (f : α → γ) (g : β → γ)
(μ : Measure α := by volume_tac)
(ν : Measure β := by volume_tac) : Prop where
aemeasurable_fst : AEMeasurable f μ
aemeasurable_snd : AEMeasurable g ν
map_eq : Measure.map f μ = Measure.map g ν
#align probability_theory.ident_distrib ProbabilityTheory.IdentDistrib
namespace IdentDistrib
open TopologicalSpace
variable {μ : Measure α} {ν : Measure β} {f : α → γ} {g : β → γ}
protected theorem refl (hf : AEMeasurable f μ) : IdentDistrib f f μ μ :=
{ aemeasurable_fst := hf
aemeasurable_snd := hf
map_eq := rfl }
#align probability_theory.ident_distrib.refl ProbabilityTheory.IdentDistrib.refl
protected theorem symm (h : IdentDistrib f g μ ν) : IdentDistrib g f ν μ :=
{ aemeasurable_fst := h.aemeasurable_snd
aemeasurable_snd := h.aemeasurable_fst
map_eq := h.map_eq.symm }
#align probability_theory.ident_distrib.symm ProbabilityTheory.IdentDistrib.symm
protected theorem trans {ρ : Measure δ} {h : δ → γ} (h₁ : IdentDistrib f g μ ν)
(h₂ : IdentDistrib g h ν ρ) : IdentDistrib f h μ ρ :=
{ aemeasurable_fst := h₁.aemeasurable_fst
aemeasurable_snd := h₂.aemeasurable_snd
map_eq := h₁.map_eq.trans h₂.map_eq }
#align probability_theory.ident_distrib.trans ProbabilityTheory.IdentDistrib.trans
protected theorem comp_of_aemeasurable {u : γ → δ} (h : IdentDistrib f g μ ν)
(hu : AEMeasurable u (Measure.map f μ)) : IdentDistrib (u ∘ f) (u ∘ g) μ ν :=
{ aemeasurable_fst := hu.comp_aemeasurable h.aemeasurable_fst
aemeasurable_snd := by rw [h.map_eq] at hu; exact hu.comp_aemeasurable h.aemeasurable_snd
map_eq := by
rw [← AEMeasurable.map_map_of_aemeasurable hu h.aemeasurable_fst, ←
AEMeasurable.map_map_of_aemeasurable _ h.aemeasurable_snd, h.map_eq]
rwa [← h.map_eq] }
#align probability_theory.ident_distrib.comp_of_ae_measurable ProbabilityTheory.IdentDistrib.comp_of_aemeasurable
protected theorem comp {u : γ → δ} (h : IdentDistrib f g μ ν) (hu : Measurable u) :
IdentDistrib (u ∘ f) (u ∘ g) μ ν :=
h.comp_of_aemeasurable hu.aemeasurable
#align probability_theory.ident_distrib.comp ProbabilityTheory.IdentDistrib.comp
protected theorem of_ae_eq {g : α → γ} (hf : AEMeasurable f μ) (heq : f =ᵐ[μ] g) :
IdentDistrib f g μ μ :=
{ aemeasurable_fst := hf
aemeasurable_snd := hf.congr heq
map_eq := Measure.map_congr heq }
#align probability_theory.ident_distrib.of_ae_eq ProbabilityTheory.IdentDistrib.of_ae_eq
lemma _root_.MeasureTheory.AEMeasurable.identDistrib_mk
(hf : AEMeasurable f μ) : IdentDistrib f (hf.mk f) μ μ :=
IdentDistrib.of_ae_eq hf hf.ae_eq_mk
lemma _root_.MeasureTheory.AEStronglyMeasurable.identDistrib_mk
[TopologicalSpace γ] [PseudoMetrizableSpace γ] [BorelSpace γ]
(hf : AEStronglyMeasurable f μ) : IdentDistrib f (hf.mk f) μ μ :=
IdentDistrib.of_ae_eq hf.aemeasurable hf.ae_eq_mk
theorem measure_mem_eq (h : IdentDistrib f g μ ν) {s : Set γ} (hs : MeasurableSet s) :
μ (f ⁻¹' s) = ν (g ⁻¹' s) := by
rw [← Measure.map_apply_of_aemeasurable h.aemeasurable_fst hs, ←
Measure.map_apply_of_aemeasurable h.aemeasurable_snd hs, h.map_eq]
#align probability_theory.ident_distrib.measure_mem_eq ProbabilityTheory.IdentDistrib.measure_mem_eq
alias measure_preimage_eq := measure_mem_eq
#align probability_theory.ident_distrib.measure_preimage_eq ProbabilityTheory.IdentDistrib.measure_preimage_eq
theorem ae_snd (h : IdentDistrib f g μ ν) {p : γ → Prop} (pmeas : MeasurableSet {x | p x})
(hp : ∀ᵐ x ∂μ, p (f x)) : ∀ᵐ x ∂ν, p (g x) := by
apply (ae_map_iff h.aemeasurable_snd pmeas).1
rw [← h.map_eq]
exact (ae_map_iff h.aemeasurable_fst pmeas).2 hp
#align probability_theory.ident_distrib.ae_snd ProbabilityTheory.IdentDistrib.ae_snd
theorem ae_mem_snd (h : IdentDistrib f g μ ν) {t : Set γ} (tmeas : MeasurableSet t)
(ht : ∀ᵐ x ∂μ, f x ∈ t) : ∀ᵐ x ∂ν, g x ∈ t :=
h.ae_snd tmeas ht
#align probability_theory.ident_distrib.ae_mem_snd ProbabilityTheory.IdentDistrib.ae_mem_snd
theorem aestronglyMeasurable_fst [TopologicalSpace γ] [MetrizableSpace γ] [OpensMeasurableSpace γ]
[SecondCountableTopology γ] (h : IdentDistrib f g μ ν) : AEStronglyMeasurable f μ :=
h.aemeasurable_fst.aestronglyMeasurable
#align probability_theory.ident_distrib.ae_strongly_measurable_fst ProbabilityTheory.IdentDistrib.aestronglyMeasurable_fst
theorem aestronglyMeasurable_snd [TopologicalSpace γ] [MetrizableSpace γ] [BorelSpace γ]
(h : IdentDistrib f g μ ν) (hf : AEStronglyMeasurable f μ) : AEStronglyMeasurable g ν := by
refine aestronglyMeasurable_iff_aemeasurable_separable.2 ⟨h.aemeasurable_snd, ?_⟩
rcases (aestronglyMeasurable_iff_aemeasurable_separable.1 hf).2 with ⟨t, t_sep, ht⟩
refine ⟨closure t, t_sep.closure, ?_⟩
apply h.ae_mem_snd isClosed_closure.measurableSet
filter_upwards [ht] with x hx using subset_closure hx
#align probability_theory.ident_distrib.ae_strongly_measurable_snd ProbabilityTheory.IdentDistrib.aestronglyMeasurable_snd
theorem aestronglyMeasurable_iff [TopologicalSpace γ] [MetrizableSpace γ] [BorelSpace γ]
(h : IdentDistrib f g μ ν) : AEStronglyMeasurable f μ ↔ AEStronglyMeasurable g ν :=
⟨fun hf => h.aestronglyMeasurable_snd hf, fun hg => h.symm.aestronglyMeasurable_snd hg⟩
#align probability_theory.ident_distrib.ae_strongly_measurable_iff ProbabilityTheory.IdentDistrib.aestronglyMeasurable_iff
theorem essSup_eq [ConditionallyCompleteLinearOrder γ] [TopologicalSpace γ] [OpensMeasurableSpace γ]
[OrderClosedTopology γ] (h : IdentDistrib f g μ ν) : essSup f μ = essSup g ν := by
have I : ∀ a, μ {x : α | a < f x} = ν {x : β | a < g x} := fun a =>
h.measure_mem_eq measurableSet_Ioi
simp_rw [essSup_eq_sInf, I]
#align probability_theory.ident_distrib.ess_sup_eq ProbabilityTheory.IdentDistrib.essSup_eq
| Mathlib/Probability/IdentDistrib.lean | 183 | 187 | theorem lintegral_eq {f : α → ℝ≥0∞} {g : β → ℝ≥0∞} (h : IdentDistrib f g μ ν) :
∫⁻ x, f x ∂μ = ∫⁻ x, g x ∂ν := by |
change ∫⁻ x, id (f x) ∂μ = ∫⁻ x, id (g x) ∂ν
rw [← lintegral_map' aemeasurable_id h.aemeasurable_fst, ←
lintegral_map' aemeasurable_id h.aemeasurable_snd, h.map_eq]
|
import Mathlib.Order.Cover
import Mathlib.Order.Interval.Finset.Defs
#align_import data.finset.locally_finite from "leanprover-community/mathlib"@"442a83d738cb208d3600056c489be16900ba701d"
assert_not_exists MonoidWithZero
assert_not_exists Finset.sum
open Function OrderDual
open FinsetInterval
variable {ι α : Type*}
namespace Finset
section Preorder
variable [Preorder α]
section LocallyFiniteOrder
variable [LocallyFiniteOrder α] {a a₁ a₂ b b₁ b₂ c x : α}
@[simp, aesop safe apply (rule_sets := [finsetNonempty])]
theorem nonempty_Icc : (Icc a b).Nonempty ↔ a ≤ b := by
rw [← coe_nonempty, coe_Icc, Set.nonempty_Icc]
#align finset.nonempty_Icc Finset.nonempty_Icc
@[simp, aesop safe apply (rule_sets := [finsetNonempty])]
| Mathlib/Order/Interval/Finset/Basic.lean | 62 | 63 | theorem nonempty_Ico : (Ico a b).Nonempty ↔ a < b := by |
rw [← coe_nonempty, coe_Ico, Set.nonempty_Ico]
|
import Mathlib.Algebra.Polynomial.AlgebraMap
import Mathlib.Algebra.Polynomial.Inductions
import Mathlib.Algebra.Polynomial.Splits
import Mathlib.Analysis.Normed.Field.Basic
import Mathlib.RingTheory.Polynomial.Vieta
#align_import topology.algebra.polynomial from "leanprover-community/mathlib"@"565eb991e264d0db702722b4bde52ee5173c9950"
open IsAbsoluteValue Filter
namespace Polynomial
open Polynomial
| Mathlib/Topology/Algebra/Polynomial.lean | 105 | 120 | theorem tendsto_abv_eval₂_atTop {R S k α : Type*} [Semiring R] [Ring S] [LinearOrderedField k]
(f : R →+* S) (abv : S → k) [IsAbsoluteValue abv] (p : R[X]) (hd : 0 < degree p)
(hf : f p.leadingCoeff ≠ 0) {l : Filter α} {z : α → S} (hz : Tendsto (abv ∘ z) l atTop) :
Tendsto (fun x => abv (p.eval₂ f (z x))) l atTop := by |
revert hf; refine degree_pos_induction_on p hd ?_ ?_ ?_ <;> clear hd p
· rintro _ - hc
rw [leadingCoeff_mul_X, leadingCoeff_C] at hc
simpa [abv_mul abv] using hz.const_mul_atTop ((abv_pos abv).2 hc)
· intro _ _ ihp hf
rw [leadingCoeff_mul_X] at hf
simpa [abv_mul abv] using (ihp hf).atTop_mul_atTop hz
· intro _ a hd ihp hf
rw [add_comm, leadingCoeff_add_of_degree_lt (degree_C_le.trans_lt hd)] at hf
refine tendsto_atTop_of_add_const_right (abv (-f a)) ?_
refine tendsto_atTop_mono (fun _ => abv_add abv _ _) ?_
simpa using ihp hf
|
import Mathlib.CategoryTheory.Monoidal.Free.Coherence
import Mathlib.CategoryTheory.Monoidal.Discrete
import Mathlib.CategoryTheory.Monoidal.NaturalTransformation
import Mathlib.CategoryTheory.Monoidal.Opposite
import Mathlib.Tactic.CategoryTheory.Coherence
import Mathlib.CategoryTheory.CommSq
#align_import category_theory.monoidal.braided from "leanprover-community/mathlib"@"2efd2423f8d25fa57cf7a179f5d8652ab4d0df44"
open CategoryTheory MonoidalCategory
universe v v₁ v₂ v₃ u u₁ u₂ u₃
namespace CategoryTheory
class BraidedCategory (C : Type u) [Category.{v} C] [MonoidalCategory.{v} C] where
braiding : ∀ X Y : C, X ⊗ Y ≅ Y ⊗ X
braiding_naturality_right :
∀ (X : C) {Y Z : C} (f : Y ⟶ Z),
X ◁ f ≫ (braiding X Z).hom = (braiding X Y).hom ≫ f ▷ X := by
aesop_cat
braiding_naturality_left :
∀ {X Y : C} (f : X ⟶ Y) (Z : C),
f ▷ Z ≫ (braiding Y Z).hom = (braiding X Z).hom ≫ Z ◁ f := by
aesop_cat
hexagon_forward :
∀ X Y Z : C,
(α_ X Y Z).hom ≫ (braiding X (Y ⊗ Z)).hom ≫ (α_ Y Z X).hom =
((braiding X Y).hom ▷ Z) ≫ (α_ Y X Z).hom ≫ (Y ◁ (braiding X Z).hom) := by
aesop_cat
hexagon_reverse :
∀ X Y Z : C,
(α_ X Y Z).inv ≫ (braiding (X ⊗ Y) Z).hom ≫ (α_ Z X Y).inv =
(X ◁ (braiding Y Z).hom) ≫ (α_ X Z Y).inv ≫ ((braiding X Z).hom ▷ Y) := by
aesop_cat
#align category_theory.braided_category CategoryTheory.BraidedCategory
attribute [reassoc (attr := simp)]
BraidedCategory.braiding_naturality_left
BraidedCategory.braiding_naturality_right
attribute [reassoc] BraidedCategory.hexagon_forward BraidedCategory.hexagon_reverse
open Category
open MonoidalCategory
open BraidedCategory
@[inherit_doc]
notation "β_" => BraidedCategory.braiding
namespace BraidedCategory
variable {C : Type u} [Category.{v} C] [MonoidalCategory.{v} C] [BraidedCategory.{v} C]
@[simp, reassoc]
theorem braiding_tensor_left (X Y Z : C) :
(β_ (X ⊗ Y) Z).hom =
(α_ X Y Z).hom ≫ X ◁ (β_ Y Z).hom ≫ (α_ X Z Y).inv ≫
(β_ X Z).hom ▷ Y ≫ (α_ Z X Y).hom := by
apply (cancel_epi (α_ X Y Z).inv).1
apply (cancel_mono (α_ Z X Y).inv).1
simp [hexagon_reverse]
@[simp, reassoc]
theorem braiding_tensor_right (X Y Z : C) :
(β_ X (Y ⊗ Z)).hom =
(α_ X Y Z).inv ≫ (β_ X Y).hom ▷ Z ≫ (α_ Y X Z).hom ≫
Y ◁ (β_ X Z).hom ≫ (α_ Y Z X).inv := by
apply (cancel_epi (α_ X Y Z).hom).1
apply (cancel_mono (α_ Y Z X).hom).1
simp [hexagon_forward]
@[simp, reassoc]
theorem braiding_inv_tensor_left (X Y Z : C) :
(β_ (X ⊗ Y) Z).inv =
(α_ Z X Y).inv ≫ (β_ X Z).inv ▷ Y ≫ (α_ X Z Y).hom ≫
X ◁ (β_ Y Z).inv ≫ (α_ X Y Z).inv :=
eq_of_inv_eq_inv (by simp)
@[simp, reassoc]
theorem braiding_inv_tensor_right (X Y Z : C) :
(β_ X (Y ⊗ Z)).inv =
(α_ Y Z X).hom ≫ Y ◁ (β_ X Z).inv ≫ (α_ Y X Z).inv ≫
(β_ X Y).inv ▷ Z ≫ (α_ X Y Z).hom :=
eq_of_inv_eq_inv (by simp)
@[reassoc (attr := simp)]
theorem braiding_naturality {X X' Y Y' : C} (f : X ⟶ Y) (g : X' ⟶ Y') :
(f ⊗ g) ≫ (braiding Y Y').hom = (braiding X X').hom ≫ (g ⊗ f) := by
rw [tensorHom_def' f g, tensorHom_def g f]
simp_rw [Category.assoc, braiding_naturality_left, braiding_naturality_right_assoc]
@[reassoc (attr := simp)]
theorem braiding_inv_naturality_right (X : C) {Y Z : C} (f : Y ⟶ Z) :
X ◁ f ≫ (β_ Z X).inv = (β_ Y X).inv ≫ f ▷ X :=
CommSq.w <| .vert_inv <| .mk <| braiding_naturality_left f X
@[reassoc (attr := simp)]
theorem braiding_inv_naturality_left {X Y : C} (f : X ⟶ Y) (Z : C) :
f ▷ Z ≫ (β_ Z Y).inv = (β_ Z X).inv ≫ Z ◁ f :=
CommSq.w <| .vert_inv <| .mk <| braiding_naturality_right Z f
@[reassoc (attr := simp)]
theorem braiding_inv_naturality {X X' Y Y' : C} (f : X ⟶ Y) (g : X' ⟶ Y') :
(f ⊗ g) ≫ (β_ Y' Y).inv = (β_ X' X).inv ≫ (g ⊗ f) :=
CommSq.w <| .vert_inv <| .mk <| braiding_naturality g f
@[reassoc]
| Mathlib/CategoryTheory/Monoidal/Braided/Basic.lean | 146 | 153 | theorem yang_baxter (X Y Z : C) :
(α_ X Y Z).inv ≫ (β_ X Y).hom ▷ Z ≫ (α_ Y X Z).hom ≫
Y ◁ (β_ X Z).hom ≫ (α_ Y Z X).inv ≫ (β_ Y Z).hom ▷ X ≫ (α_ Z Y X).hom =
X ◁ (β_ Y Z).hom ≫ (α_ X Z Y).inv ≫ (β_ X Z).hom ▷ Y ≫
(α_ Z X Y).hom ≫ Z ◁ (β_ X Y).hom := by |
rw [← braiding_tensor_right_assoc X Y Z, ← cancel_mono (α_ Z Y X).inv]
repeat rw [assoc]
rw [Iso.hom_inv_id, comp_id, ← braiding_naturality_right, braiding_tensor_right]
|
import Mathlib.SetTheory.Cardinal.Ordinal
import Mathlib.RingTheory.Artinian
#align_import ring_theory.localization.cardinality from "leanprover-community/mathlib"@"3b09a2601bb7690643936643e99bba0fedfbf6ed"
open Cardinal nonZeroDivisors
universe u v
namespace IsLocalization
variable {R : Type u} [CommRing R] (S : Submonoid R) {L : Type u} [CommRing L] [Algebra R L]
[IsLocalization S L]
| Mathlib/RingTheory/Localization/Cardinality.lean | 38 | 48 | theorem card_le : #L ≤ #R := by |
classical
cases fintypeOrInfinite R
· exact Cardinal.mk_le_of_surjective (IsArtinianRing.localization_surjective S _)
erw [← Cardinal.mul_eq_self <| Cardinal.aleph0_le_mk R]
set f : R × R → L := fun aa => IsLocalization.mk' _ aa.1 (if h : aa.2 ∈ S then ⟨aa.2, h⟩ else 1)
refine @Cardinal.mk_le_of_surjective _ _ f fun a => ?_
obtain ⟨x, y, h⟩ := IsLocalization.mk'_surjective S a
use (x, y)
dsimp [f]
rwa [dif_pos <| show ↑y ∈ S from y.2, SetLike.eta]
|
import Mathlib.Data.Fintype.Option
import Mathlib.Topology.Separation
import Mathlib.Topology.Sets.Opens
#align_import topology.alexandroff from "leanprover-community/mathlib"@"dc6c365e751e34d100e80fe6e314c3c3e0fd2988"
open Set Filter Topology
variable {X : Type*}
def OnePoint (X : Type*) :=
Option X
#align alexandroff OnePoint
instance [Repr X] : Repr (OnePoint X) :=
⟨fun o _ =>
match o with
| none => "∞"
| some a => "↑" ++ repr a⟩
namespace OnePoint
@[match_pattern] def infty : OnePoint X := none
#align alexandroff.infty OnePoint.infty
@[inherit_doc]
scoped notation "∞" => OnePoint.infty
@[coe, match_pattern] def some : X → OnePoint X := Option.some
instance : CoeTC X (OnePoint X) := ⟨some⟩
instance : Inhabited (OnePoint X) := ⟨∞⟩
instance [Fintype X] : Fintype (OnePoint X) :=
inferInstanceAs (Fintype (Option X))
instance infinite [Infinite X] : Infinite (OnePoint X) :=
inferInstanceAs (Infinite (Option X))
#align alexandroff.infinite OnePoint.infinite
theorem coe_injective : Function.Injective ((↑) : X → OnePoint X) :=
Option.some_injective X
#align alexandroff.coe_injective OnePoint.coe_injective
@[norm_cast]
theorem coe_eq_coe {x y : X} : (x : OnePoint X) = y ↔ x = y :=
coe_injective.eq_iff
#align alexandroff.coe_eq_coe OnePoint.coe_eq_coe
@[simp]
theorem coe_ne_infty (x : X) : (x : OnePoint X) ≠ ∞ :=
nofun
#align alexandroff.coe_ne_infty OnePoint.coe_ne_infty
@[simp]
theorem infty_ne_coe (x : X) : ∞ ≠ (x : OnePoint X) :=
nofun
#align alexandroff.infty_ne_coe OnePoint.infty_ne_coe
@[elab_as_elim]
protected def rec {C : OnePoint X → Sort*} (h₁ : C ∞) (h₂ : ∀ x : X, C x) :
∀ z : OnePoint X, C z
| ∞ => h₁
| (x : X) => h₂ x
#align alexandroff.rec OnePoint.rec
theorem isCompl_range_coe_infty : IsCompl (range ((↑) : X → OnePoint X)) {∞} :=
isCompl_range_some_none X
#align alexandroff.is_compl_range_coe_infty OnePoint.isCompl_range_coe_infty
-- Porting note: moved @[simp] to a new lemma
theorem range_coe_union_infty : range ((↑) : X → OnePoint X) ∪ {∞} = univ :=
range_some_union_none X
#align alexandroff.range_coe_union_infty OnePoint.range_coe_union_infty
@[simp]
theorem insert_infty_range_coe : insert ∞ (range (@some X)) = univ :=
insert_none_range_some _
@[simp]
theorem range_coe_inter_infty : range ((↑) : X → OnePoint X) ∩ {∞} = ∅ :=
range_some_inter_none X
#align alexandroff.range_coe_inter_infty OnePoint.range_coe_inter_infty
@[simp]
theorem compl_range_coe : (range ((↑) : X → OnePoint X))ᶜ = {∞} :=
compl_range_some X
#align alexandroff.compl_range_coe OnePoint.compl_range_coe
theorem compl_infty : ({∞}ᶜ : Set (OnePoint X)) = range ((↑) : X → OnePoint X) :=
(@isCompl_range_coe_infty X).symm.compl_eq
#align alexandroff.compl_infty OnePoint.compl_infty
theorem compl_image_coe (s : Set X) : ((↑) '' s : Set (OnePoint X))ᶜ = (↑) '' sᶜ ∪ {∞} := by
rw [coe_injective.compl_image_eq, compl_range_coe]
#align alexandroff.compl_image_coe OnePoint.compl_image_coe
theorem ne_infty_iff_exists {x : OnePoint X} : x ≠ ∞ ↔ ∃ y : X, (y : OnePoint X) = x := by
induction x using OnePoint.rec <;> simp
#align alexandroff.ne_infty_iff_exists OnePoint.ne_infty_iff_exists
instance canLift : CanLift (OnePoint X) X (↑) fun x => x ≠ ∞ :=
WithTop.canLift
#align alexandroff.can_lift OnePoint.canLift
theorem not_mem_range_coe_iff {x : OnePoint X} : x ∉ range some ↔ x = ∞ := by
rw [← mem_compl_iff, compl_range_coe, mem_singleton_iff]
#align alexandroff.not_mem_range_coe_iff OnePoint.not_mem_range_coe_iff
theorem infty_not_mem_range_coe : ∞ ∉ range ((↑) : X → OnePoint X) :=
not_mem_range_coe_iff.2 rfl
#align alexandroff.infty_not_mem_range_coe OnePoint.infty_not_mem_range_coe
theorem infty_not_mem_image_coe {s : Set X} : ∞ ∉ ((↑) : X → OnePoint X) '' s :=
not_mem_subset (image_subset_range _ _) infty_not_mem_range_coe
#align alexandroff.infty_not_mem_image_coe OnePoint.infty_not_mem_image_coe
@[simp]
theorem coe_preimage_infty : ((↑) : X → OnePoint X) ⁻¹' {∞} = ∅ := by
ext
simp
#align alexandroff.coe_preimage_infty OnePoint.coe_preimage_infty
variable [TopologicalSpace X]
instance : TopologicalSpace (OnePoint X) where
IsOpen s := (∞ ∈ s → IsCompact (((↑) : X → OnePoint X) ⁻¹' s)ᶜ) ∧
IsOpen (((↑) : X → OnePoint X) ⁻¹' s)
isOpen_univ := by simp
isOpen_inter s t := by
rintro ⟨hms, hs⟩ ⟨hmt, ht⟩
refine ⟨?_, hs.inter ht⟩
rintro ⟨hms', hmt'⟩
simpa [compl_inter] using (hms hms').union (hmt hmt')
isOpen_sUnion S ho := by
suffices IsOpen ((↑) ⁻¹' ⋃₀ S : Set X) by
refine ⟨?_, this⟩
rintro ⟨s, hsS : s ∈ S, hs : ∞ ∈ s⟩
refine IsCompact.of_isClosed_subset ((ho s hsS).1 hs) this.isClosed_compl ?_
exact compl_subset_compl.mpr (preimage_mono <| subset_sUnion_of_mem hsS)
rw [preimage_sUnion]
exact isOpen_biUnion fun s hs => (ho s hs).2
variable {s : Set (OnePoint X)} {t : Set X}
theorem isOpen_def :
IsOpen s ↔ (∞ ∈ s → IsCompact ((↑) ⁻¹' s : Set X)ᶜ) ∧ IsOpen ((↑) ⁻¹' s : Set X) :=
Iff.rfl
#align alexandroff.is_open_def OnePoint.isOpen_def
theorem isOpen_iff_of_mem' (h : ∞ ∈ s) :
IsOpen s ↔ IsCompact ((↑) ⁻¹' s : Set X)ᶜ ∧ IsOpen ((↑) ⁻¹' s : Set X) := by
simp [isOpen_def, h]
#align alexandroff.is_open_iff_of_mem' OnePoint.isOpen_iff_of_mem'
theorem isOpen_iff_of_mem (h : ∞ ∈ s) :
IsOpen s ↔ IsClosed ((↑) ⁻¹' s : Set X)ᶜ ∧ IsCompact ((↑) ⁻¹' s : Set X)ᶜ := by
simp only [isOpen_iff_of_mem' h, isClosed_compl_iff, and_comm]
#align alexandroff.is_open_iff_of_mem OnePoint.isOpen_iff_of_mem
| Mathlib/Topology/Compactification/OnePoint.lean | 221 | 222 | theorem isOpen_iff_of_not_mem (h : ∞ ∉ s) : IsOpen s ↔ IsOpen ((↑) ⁻¹' s : Set X) := by |
simp [isOpen_def, h]
|
import Mathlib.Analysis.Calculus.BumpFunction.FiniteDimension
import Mathlib.Geometry.Manifold.ContMDiff.Atlas
import Mathlib.Geometry.Manifold.ContMDiff.NormedSpace
#align_import geometry.manifold.bump_function from "leanprover-community/mathlib"@"b018406ad2f2a73223a3a9e198ccae61e6f05318"
universe uE uF uH uM
variable {E : Type uE} [NormedAddCommGroup E] [NormedSpace ℝ E] [FiniteDimensional ℝ E]
{H : Type uH} [TopologicalSpace H] (I : ModelWithCorners ℝ E H) {M : Type uM} [TopologicalSpace M]
[ChartedSpace H M] [SmoothManifoldWithCorners I M]
open Function Filter FiniteDimensional Set Metric
open scoped Topology Manifold Classical Filter
noncomputable section
structure SmoothBumpFunction (c : M) extends ContDiffBump (extChartAt I c c) where
closedBall_subset : closedBall (extChartAt I c c) rOut ∩ range I ⊆ (extChartAt I c).target
#align smooth_bump_function SmoothBumpFunction
namespace SmoothBumpFunction
variable {c : M} (f : SmoothBumpFunction I c) {x : M} {I}
@[coe] def toFun : M → ℝ :=
indicator (chartAt H c).source (f.toContDiffBump ∘ extChartAt I c)
#align smooth_bump_function.to_fun SmoothBumpFunction.toFun
instance : CoeFun (SmoothBumpFunction I c) fun _ => M → ℝ :=
⟨toFun⟩
theorem coe_def : ⇑f = indicator (chartAt H c).source (f.toContDiffBump ∘ extChartAt I c) :=
rfl
#align smooth_bump_function.coe_def SmoothBumpFunction.coe_def
theorem rOut_pos : 0 < f.rOut :=
f.toContDiffBump.rOut_pos
set_option linter.uppercaseLean3 false in
#align smooth_bump_function.R_pos SmoothBumpFunction.rOut_pos
theorem ball_subset : ball (extChartAt I c c) f.rOut ∩ range I ⊆ (extChartAt I c).target :=
Subset.trans (inter_subset_inter_left _ ball_subset_closedBall) f.closedBall_subset
#align smooth_bump_function.ball_subset SmoothBumpFunction.ball_subset
theorem ball_inter_range_eq_ball_inter_target :
ball (extChartAt I c c) f.rOut ∩ range I =
ball (extChartAt I c c) f.rOut ∩ (extChartAt I c).target :=
(subset_inter inter_subset_left f.ball_subset).antisymm <| inter_subset_inter_right _ <|
extChartAt_target_subset_range _ _
theorem eqOn_source : EqOn f (f.toContDiffBump ∘ extChartAt I c) (chartAt H c).source :=
eqOn_indicator
#align smooth_bump_function.eq_on_source SmoothBumpFunction.eqOn_source
theorem eventuallyEq_of_mem_source (hx : x ∈ (chartAt H c).source) :
f =ᶠ[𝓝 x] f.toContDiffBump ∘ extChartAt I c :=
f.eqOn_source.eventuallyEq_of_mem <| (chartAt H c).open_source.mem_nhds hx
#align smooth_bump_function.eventually_eq_of_mem_source SmoothBumpFunction.eventuallyEq_of_mem_source
theorem one_of_dist_le (hs : x ∈ (chartAt H c).source)
(hd : dist (extChartAt I c x) (extChartAt I c c) ≤ f.rIn) : f x = 1 := by
simp only [f.eqOn_source hs, (· ∘ ·), f.one_of_mem_closedBall hd]
#align smooth_bump_function.one_of_dist_le SmoothBumpFunction.one_of_dist_le
theorem support_eq_inter_preimage :
support f = (chartAt H c).source ∩ extChartAt I c ⁻¹' ball (extChartAt I c c) f.rOut := by
rw [coe_def, support_indicator, support_comp_eq_preimage, ← extChartAt_source I,
← (extChartAt I c).symm_image_target_inter_eq', ← (extChartAt I c).symm_image_target_inter_eq',
f.support_eq]
#align smooth_bump_function.support_eq_inter_preimage SmoothBumpFunction.support_eq_inter_preimage
theorem isOpen_support : IsOpen (support f) := by
rw [support_eq_inter_preimage]
exact isOpen_extChartAt_preimage I c isOpen_ball
#align smooth_bump_function.is_open_support SmoothBumpFunction.isOpen_support
theorem support_eq_symm_image :
support f = (extChartAt I c).symm '' (ball (extChartAt I c c) f.rOut ∩ range I) := by
rw [f.support_eq_inter_preimage, ← extChartAt_source I,
← (extChartAt I c).symm_image_target_inter_eq', inter_comm,
ball_inter_range_eq_ball_inter_target]
#align smooth_bump_function.support_eq_symm_image SmoothBumpFunction.support_eq_symm_image
| Mathlib/Geometry/Manifold/BumpFunction.lean | 131 | 132 | theorem support_subset_source : support f ⊆ (chartAt H c).source := by |
rw [f.support_eq_inter_preimage, ← extChartAt_source I]; exact inter_subset_left
|
import Mathlib.Analysis.Convex.Combination
import Mathlib.Analysis.Convex.Strict
import Mathlib.Topology.Connected.PathConnected
import Mathlib.Topology.Algebra.Affine
import Mathlib.Topology.Algebra.Module.Basic
#align_import analysis.convex.topology from "leanprover-community/mathlib"@"0e3aacdc98d25e0afe035c452d876d28cbffaa7e"
assert_not_exists Norm
open Metric Bornology Set Pointwise Convex
variable {ι 𝕜 E : Type*}
theorem Real.convex_iff_isPreconnected {s : Set ℝ} : Convex ℝ s ↔ IsPreconnected s :=
convex_iff_ordConnected.trans isPreconnected_iff_ordConnected.symm
#align real.convex_iff_is_preconnected Real.convex_iff_isPreconnected
alias ⟨_, IsPreconnected.convex⟩ := Real.convex_iff_isPreconnected
#align is_preconnected.convex IsPreconnected.convex
section ContinuousConstSMul
variable [LinearOrderedField 𝕜] [AddCommGroup E] [Module 𝕜 E] [TopologicalSpace E]
[TopologicalAddGroup E] [ContinuousConstSMul 𝕜 E]
theorem Convex.combo_interior_closure_subset_interior {s : Set E} (hs : Convex 𝕜 s) {a b : 𝕜}
(ha : 0 < a) (hb : 0 ≤ b) (hab : a + b = 1) : a • interior s + b • closure s ⊆ interior s :=
interior_smul₀ ha.ne' s ▸
calc
interior (a • s) + b • closure s ⊆ interior (a • s) + closure (b • s) :=
add_subset_add Subset.rfl (smul_closure_subset b s)
_ = interior (a • s) + b • s := by rw [isOpen_interior.add_closure (b • s)]
_ ⊆ interior (a • s + b • s) := subset_interior_add_left
_ ⊆ interior s := interior_mono <| hs.set_combo_subset ha.le hb hab
#align convex.combo_interior_closure_subset_interior Convex.combo_interior_closure_subset_interior
theorem Convex.combo_interior_self_subset_interior {s : Set E} (hs : Convex 𝕜 s) {a b : 𝕜}
(ha : 0 < a) (hb : 0 ≤ b) (hab : a + b = 1) : a • interior s + b • s ⊆ interior s :=
calc
a • interior s + b • s ⊆ a • interior s + b • closure s :=
add_subset_add Subset.rfl <| image_subset _ subset_closure
_ ⊆ interior s := hs.combo_interior_closure_subset_interior ha hb hab
#align convex.combo_interior_self_subset_interior Convex.combo_interior_self_subset_interior
theorem Convex.combo_closure_interior_subset_interior {s : Set E} (hs : Convex 𝕜 s) {a b : 𝕜}
(ha : 0 ≤ a) (hb : 0 < b) (hab : a + b = 1) : a • closure s + b • interior s ⊆ interior s := by
rw [add_comm]
exact hs.combo_interior_closure_subset_interior hb ha (add_comm a b ▸ hab)
#align convex.combo_closure_interior_subset_interior Convex.combo_closure_interior_subset_interior
| Mathlib/Analysis/Convex/Topology.lean | 157 | 160 | theorem Convex.combo_self_interior_subset_interior {s : Set E} (hs : Convex 𝕜 s) {a b : 𝕜}
(ha : 0 ≤ a) (hb : 0 < b) (hab : a + b = 1) : a • s + b • interior s ⊆ interior s := by |
rw [add_comm]
exact hs.combo_interior_self_subset_interior hb ha (add_comm a b ▸ hab)
|
import Mathlib.Analysis.NormedSpace.AffineIsometry
import Mathlib.Topology.Algebra.ContinuousAffineMap
import Mathlib.Analysis.NormedSpace.OperatorNorm.NormedSpace
#align_import analysis.normed_space.continuous_affine_map from "leanprover-community/mathlib"@"17ef379e997badd73e5eabb4d38f11919ab3c4b3"
namespace ContinuousAffineMap
variable {𝕜 R V W W₂ P Q Q₂ : Type*}
variable [NormedAddCommGroup V] [MetricSpace P] [NormedAddTorsor V P]
variable [NormedAddCommGroup W] [MetricSpace Q] [NormedAddTorsor W Q]
variable [NormedAddCommGroup W₂] [MetricSpace Q₂] [NormedAddTorsor W₂ Q₂]
variable [NormedField R] [NormedSpace R V] [NormedSpace R W] [NormedSpace R W₂]
variable [NontriviallyNormedField 𝕜] [NormedSpace 𝕜 V] [NormedSpace 𝕜 W] [NormedSpace 𝕜 W₂]
def contLinear (f : P →ᴬ[R] Q) : V →L[R] W :=
{ f.linear with
toFun := f.linear
cont := by rw [AffineMap.continuous_linear_iff]; exact f.cont }
#align continuous_affine_map.cont_linear ContinuousAffineMap.contLinear
@[simp]
theorem coe_contLinear (f : P →ᴬ[R] Q) : (f.contLinear : V → W) = f.linear :=
rfl
#align continuous_affine_map.coe_cont_linear ContinuousAffineMap.coe_contLinear
@[simp]
theorem coe_contLinear_eq_linear (f : P →ᴬ[R] Q) :
(f.contLinear : V →ₗ[R] W) = (f : P →ᵃ[R] Q).linear := by ext; rfl
#align continuous_affine_map.coe_cont_linear_eq_linear ContinuousAffineMap.coe_contLinear_eq_linear
@[simp]
theorem coe_mk_const_linear_eq_linear (f : P →ᵃ[R] Q) (h) :
((⟨f, h⟩ : P →ᴬ[R] Q).contLinear : V → W) = f.linear :=
rfl
#align continuous_affine_map.coe_mk_const_linear_eq_linear ContinuousAffineMap.coe_mk_const_linear_eq_linear
theorem coe_linear_eq_coe_contLinear (f : P →ᴬ[R] Q) :
((f : P →ᵃ[R] Q).linear : V → W) = (⇑f.contLinear : V → W) :=
rfl
#align continuous_affine_map.coe_linear_eq_coe_cont_linear ContinuousAffineMap.coe_linear_eq_coe_contLinear
@[simp]
theorem comp_contLinear (f : P →ᴬ[R] Q) (g : Q →ᴬ[R] Q₂) :
(g.comp f).contLinear = g.contLinear.comp f.contLinear :=
rfl
#align continuous_affine_map.comp_cont_linear ContinuousAffineMap.comp_contLinear
@[simp]
theorem map_vadd (f : P →ᴬ[R] Q) (p : P) (v : V) : f (v +ᵥ p) = f.contLinear v +ᵥ f p :=
f.map_vadd' p v
#align continuous_affine_map.map_vadd ContinuousAffineMap.map_vadd
@[simp]
theorem contLinear_map_vsub (f : P →ᴬ[R] Q) (p₁ p₂ : P) : f.contLinear (p₁ -ᵥ p₂) = f p₁ -ᵥ f p₂ :=
f.toAffineMap.linearMap_vsub p₁ p₂
#align continuous_affine_map.cont_linear_map_vsub ContinuousAffineMap.contLinear_map_vsub
@[simp]
theorem const_contLinear (q : Q) : (const R P q).contLinear = 0 :=
rfl
#align continuous_affine_map.const_cont_linear ContinuousAffineMap.const_contLinear
theorem contLinear_eq_zero_iff_exists_const (f : P →ᴬ[R] Q) :
f.contLinear = 0 ↔ ∃ q, f = const R P q := by
have h₁ : f.contLinear = 0 ↔ (f : P →ᵃ[R] Q).linear = 0 := by
refine ⟨fun h => ?_, fun h => ?_⟩ <;> ext
· rw [← coe_contLinear_eq_linear, h]; rfl
· rw [← coe_linear_eq_coe_contLinear, h]; rfl
have h₂ : ∀ q : Q, f = const R P q ↔ (f : P →ᵃ[R] Q) = AffineMap.const R P q := by
intro q
refine ⟨fun h => ?_, fun h => ?_⟩ <;> ext
· rw [h]; rfl
· rw [← coe_to_affineMap, h]; rfl
simp_rw [h₁, h₂]
exact (f : P →ᵃ[R] Q).linear_eq_zero_iff_exists_const
#align continuous_affine_map.cont_linear_eq_zero_iff_exists_const ContinuousAffineMap.contLinear_eq_zero_iff_exists_const
@[simp]
theorem to_affine_map_contLinear (f : V →L[R] W) : f.toContinuousAffineMap.contLinear = f := by
ext
rfl
#align continuous_affine_map.to_affine_map_cont_linear ContinuousAffineMap.to_affine_map_contLinear
@[simp]
theorem zero_contLinear : (0 : P →ᴬ[R] W).contLinear = 0 :=
rfl
#align continuous_affine_map.zero_cont_linear ContinuousAffineMap.zero_contLinear
@[simp]
theorem add_contLinear (f g : P →ᴬ[R] W) : (f + g).contLinear = f.contLinear + g.contLinear :=
rfl
#align continuous_affine_map.add_cont_linear ContinuousAffineMap.add_contLinear
@[simp]
theorem sub_contLinear (f g : P →ᴬ[R] W) : (f - g).contLinear = f.contLinear - g.contLinear :=
rfl
#align continuous_affine_map.sub_cont_linear ContinuousAffineMap.sub_contLinear
@[simp]
theorem neg_contLinear (f : P →ᴬ[R] W) : (-f).contLinear = -f.contLinear :=
rfl
#align continuous_affine_map.neg_cont_linear ContinuousAffineMap.neg_contLinear
@[simp]
theorem smul_contLinear (t : R) (f : P →ᴬ[R] W) : (t • f).contLinear = t • f.contLinear :=
rfl
#align continuous_affine_map.smul_cont_linear ContinuousAffineMap.smul_contLinear
theorem decomp (f : V →ᴬ[R] W) : (f : V → W) = f.contLinear + Function.const V (f 0) := by
rcases f with ⟨f, h⟩
rw [coe_mk_const_linear_eq_linear, coe_mk, f.decomp, Pi.add_apply, LinearMap.map_zero, zero_add,
← Function.const_def]
#align continuous_affine_map.decomp ContinuousAffineMap.decomp
section NormedSpaceStructure
variable (f : V →ᴬ[𝕜] W)
noncomputable instance hasNorm : Norm (V →ᴬ[𝕜] W) :=
⟨fun f => max ‖f 0‖ ‖f.contLinear‖⟩
#align continuous_affine_map.has_norm ContinuousAffineMap.hasNorm
theorem norm_def : ‖f‖ = max ‖f 0‖ ‖f.contLinear‖ :=
rfl
#align continuous_affine_map.norm_def ContinuousAffineMap.norm_def
theorem norm_contLinear_le : ‖f.contLinear‖ ≤ ‖f‖ :=
le_max_right _ _
#align continuous_affine_map.norm_cont_linear_le ContinuousAffineMap.norm_contLinear_le
theorem norm_image_zero_le : ‖f 0‖ ≤ ‖f‖ :=
le_max_left _ _
#align continuous_affine_map.norm_image_zero_le ContinuousAffineMap.norm_image_zero_le
@[simp]
| Mathlib/Analysis/NormedSpace/ContinuousAffineMap.lean | 177 | 181 | theorem norm_eq (h : f 0 = 0) : ‖f‖ = ‖f.contLinear‖ :=
calc
‖f‖ = max ‖f 0‖ ‖f.contLinear‖ := by | rw [norm_def]
_ = max 0 ‖f.contLinear‖ := by rw [h, norm_zero]
_ = ‖f.contLinear‖ := max_eq_right (norm_nonneg _)
|
import Mathlib.MeasureTheory.Integral.SetIntegral
#align_import measure_theory.integral.average from "leanprover-community/mathlib"@"c14c8fcde993801fca8946b0d80131a1a81d1520"
open ENNReal MeasureTheory MeasureTheory.Measure Metric Set Filter TopologicalSpace Function
open scoped Topology ENNReal Convex
variable {α E F : Type*} {m0 : MeasurableSpace α} [NormedAddCommGroup E] [NormedSpace ℝ E]
[CompleteSpace E] [NormedAddCommGroup F] [NormedSpace ℝ F] [CompleteSpace F] {μ ν : Measure α}
{s t : Set α}
namespace MeasureTheory
section NormedAddCommGroup
variable (μ)
variable {f g : α → E}
noncomputable def average (f : α → E) :=
∫ x, f x ∂(μ univ)⁻¹ • μ
#align measure_theory.average MeasureTheory.average
notation3 "⨍ "(...)", "r:60:(scoped f => f)" ∂"μ:70 => average μ r
notation3 "⨍ "(...)", "r:60:(scoped f => average volume f) => r
notation3 "⨍ "(...)" in "s", "r:60:(scoped f => f)" ∂"μ:70 => average (Measure.restrict μ s) r
notation3 "⨍ "(...)" in "s", "r:60:(scoped f => average (Measure.restrict volume s) f) => r
@[simp]
theorem average_zero : ⨍ _, (0 : E) ∂μ = 0 := by rw [average, integral_zero]
#align measure_theory.average_zero MeasureTheory.average_zero
@[simp]
theorem average_zero_measure (f : α → E) : ⨍ x, f x ∂(0 : Measure α) = 0 := by
rw [average, smul_zero, integral_zero_measure]
#align measure_theory.average_zero_measure MeasureTheory.average_zero_measure
@[simp]
theorem average_neg (f : α → E) : ⨍ x, -f x ∂μ = -⨍ x, f x ∂μ :=
integral_neg f
#align measure_theory.average_neg MeasureTheory.average_neg
theorem average_eq' (f : α → E) : ⨍ x, f x ∂μ = ∫ x, f x ∂(μ univ)⁻¹ • μ :=
rfl
#align measure_theory.average_eq' MeasureTheory.average_eq'
theorem average_eq (f : α → E) : ⨍ x, f x ∂μ = (μ univ).toReal⁻¹ • ∫ x, f x ∂μ := by
rw [average_eq', integral_smul_measure, ENNReal.toReal_inv]
#align measure_theory.average_eq MeasureTheory.average_eq
theorem average_eq_integral [IsProbabilityMeasure μ] (f : α → E) : ⨍ x, f x ∂μ = ∫ x, f x ∂μ := by
rw [average, measure_univ, inv_one, one_smul]
#align measure_theory.average_eq_integral MeasureTheory.average_eq_integral
@[simp]
theorem measure_smul_average [IsFiniteMeasure μ] (f : α → E) :
(μ univ).toReal • ⨍ x, f x ∂μ = ∫ x, f x ∂μ := by
rcases eq_or_ne μ 0 with hμ | hμ
· rw [hμ, integral_zero_measure, average_zero_measure, smul_zero]
· rw [average_eq, smul_inv_smul₀]
refine (ENNReal.toReal_pos ?_ <| measure_ne_top _ _).ne'
rwa [Ne, measure_univ_eq_zero]
#align measure_theory.measure_smul_average MeasureTheory.measure_smul_average
theorem setAverage_eq (f : α → E) (s : Set α) :
⨍ x in s, f x ∂μ = (μ s).toReal⁻¹ • ∫ x in s, f x ∂μ := by rw [average_eq, restrict_apply_univ]
#align measure_theory.set_average_eq MeasureTheory.setAverage_eq
theorem setAverage_eq' (f : α → E) (s : Set α) :
⨍ x in s, f x ∂μ = ∫ x, f x ∂(μ s)⁻¹ • μ.restrict s := by
simp only [average_eq', restrict_apply_univ]
#align measure_theory.set_average_eq' MeasureTheory.setAverage_eq'
variable {μ}
theorem average_congr {f g : α → E} (h : f =ᵐ[μ] g) : ⨍ x, f x ∂μ = ⨍ x, g x ∂μ := by
simp only [average_eq, integral_congr_ae h]
#align measure_theory.average_congr MeasureTheory.average_congr
theorem setAverage_congr (h : s =ᵐ[μ] t) : ⨍ x in s, f x ∂μ = ⨍ x in t, f x ∂μ := by
simp only [setAverage_eq, setIntegral_congr_set_ae h, measure_congr h]
#align measure_theory.set_average_congr MeasureTheory.setAverage_congr
theorem setAverage_congr_fun (hs : MeasurableSet s) (h : ∀ᵐ x ∂μ, x ∈ s → f x = g x) :
⨍ x in s, f x ∂μ = ⨍ x in s, g x ∂μ := by simp only [average_eq, setIntegral_congr_ae hs h]
#align measure_theory.set_average_congr_fun MeasureTheory.setAverage_congr_fun
theorem average_add_measure [IsFiniteMeasure μ] {ν : Measure α} [IsFiniteMeasure ν] {f : α → E}
(hμ : Integrable f μ) (hν : Integrable f ν) :
⨍ x, f x ∂(μ + ν) =
((μ univ).toReal / ((μ univ).toReal + (ν univ).toReal)) • ⨍ x, f x ∂μ +
((ν univ).toReal / ((μ univ).toReal + (ν univ).toReal)) • ⨍ x, f x ∂ν := by
simp only [div_eq_inv_mul, mul_smul, measure_smul_average, ← smul_add,
← integral_add_measure hμ hν, ← ENNReal.toReal_add (measure_ne_top μ _) (measure_ne_top ν _)]
rw [average_eq, Measure.add_apply]
#align measure_theory.average_add_measure MeasureTheory.average_add_measure
theorem average_pair {f : α → E} {g : α → F} (hfi : Integrable f μ) (hgi : Integrable g μ) :
⨍ x, (f x, g x) ∂μ = (⨍ x, f x ∂μ, ⨍ x, g x ∂μ) :=
integral_pair hfi.to_average hgi.to_average
#align measure_theory.average_pair MeasureTheory.average_pair
| Mathlib/MeasureTheory/Integral/Average.lean | 388 | 391 | theorem measure_smul_setAverage (f : α → E) {s : Set α} (h : μ s ≠ ∞) :
(μ s).toReal • ⨍ x in s, f x ∂μ = ∫ x in s, f x ∂μ := by |
haveI := Fact.mk h.lt_top
rw [← measure_smul_average, restrict_apply_univ]
|
import Mathlib.Algebra.BigOperators.Fin
import Mathlib.Algebra.Polynomial.Degree.Lemmas
#align_import data.polynomial.erase_lead from "leanprover-community/mathlib"@"fa256f00ce018e7b40e1dc756e403c86680bf448"
noncomputable section
open Polynomial
open Polynomial Finset
namespace Polynomial
variable {R : Type*} [Semiring R] {f : R[X]}
def eraseLead (f : R[X]) : R[X] :=
Polynomial.erase f.natDegree f
#align polynomial.erase_lead Polynomial.eraseLead
section EraseLead
theorem eraseLead_support (f : R[X]) : f.eraseLead.support = f.support.erase f.natDegree := by
simp only [eraseLead, support_erase]
#align polynomial.erase_lead_support Polynomial.eraseLead_support
theorem eraseLead_coeff (i : ℕ) :
f.eraseLead.coeff i = if i = f.natDegree then 0 else f.coeff i := by
simp only [eraseLead, coeff_erase]
#align polynomial.erase_lead_coeff Polynomial.eraseLead_coeff
@[simp]
theorem eraseLead_coeff_natDegree : f.eraseLead.coeff f.natDegree = 0 := by simp [eraseLead_coeff]
#align polynomial.erase_lead_coeff_nat_degree Polynomial.eraseLead_coeff_natDegree
theorem eraseLead_coeff_of_ne (i : ℕ) (hi : i ≠ f.natDegree) : f.eraseLead.coeff i = f.coeff i := by
simp [eraseLead_coeff, hi]
#align polynomial.erase_lead_coeff_of_ne Polynomial.eraseLead_coeff_of_ne
@[simp]
theorem eraseLead_zero : eraseLead (0 : R[X]) = 0 := by simp only [eraseLead, erase_zero]
#align polynomial.erase_lead_zero Polynomial.eraseLead_zero
@[simp]
theorem eraseLead_add_monomial_natDegree_leadingCoeff (f : R[X]) :
f.eraseLead + monomial f.natDegree f.leadingCoeff = f :=
(add_comm _ _).trans (f.monomial_add_erase _)
#align polynomial.erase_lead_add_monomial_nat_degree_leading_coeff Polynomial.eraseLead_add_monomial_natDegree_leadingCoeff
@[simp]
theorem eraseLead_add_C_mul_X_pow (f : R[X]) :
f.eraseLead + C f.leadingCoeff * X ^ f.natDegree = f := by
rw [C_mul_X_pow_eq_monomial, eraseLead_add_monomial_natDegree_leadingCoeff]
set_option linter.uppercaseLean3 false in
#align polynomial.erase_lead_add_C_mul_X_pow Polynomial.eraseLead_add_C_mul_X_pow
@[simp]
theorem self_sub_monomial_natDegree_leadingCoeff {R : Type*} [Ring R] (f : R[X]) :
f - monomial f.natDegree f.leadingCoeff = f.eraseLead :=
(eq_sub_iff_add_eq.mpr (eraseLead_add_monomial_natDegree_leadingCoeff f)).symm
#align polynomial.self_sub_monomial_nat_degree_leading_coeff Polynomial.self_sub_monomial_natDegree_leadingCoeff
@[simp]
| Mathlib/Algebra/Polynomial/EraseLead.lean | 83 | 85 | theorem self_sub_C_mul_X_pow {R : Type*} [Ring R] (f : R[X]) :
f - C f.leadingCoeff * X ^ f.natDegree = f.eraseLead := by |
rw [C_mul_X_pow_eq_monomial, self_sub_monomial_natDegree_leadingCoeff]
|
import Mathlib.Data.ENNReal.Inv
#align_import data.real.ennreal from "leanprover-community/mathlib"@"c14c8fcde993801fca8946b0d80131a1a81d1520"
open Set NNReal ENNReal
namespace ENNReal
section Real
variable {a b c d : ℝ≥0∞} {r p q : ℝ≥0}
theorem toReal_add (ha : a ≠ ∞) (hb : b ≠ ∞) : (a + b).toReal = a.toReal + b.toReal := by
lift a to ℝ≥0 using ha
lift b to ℝ≥0 using hb
rfl
#align ennreal.to_real_add ENNReal.toReal_add
theorem toReal_sub_of_le {a b : ℝ≥0∞} (h : b ≤ a) (ha : a ≠ ∞) :
(a - b).toReal = a.toReal - b.toReal := by
lift b to ℝ≥0 using ne_top_of_le_ne_top ha h
lift a to ℝ≥0 using ha
simp only [← ENNReal.coe_sub, ENNReal.coe_toReal, NNReal.coe_sub (ENNReal.coe_le_coe.mp h)]
#align ennreal.to_real_sub_of_le ENNReal.toReal_sub_of_le
theorem le_toReal_sub {a b : ℝ≥0∞} (hb : b ≠ ∞) : a.toReal - b.toReal ≤ (a - b).toReal := by
lift b to ℝ≥0 using hb
induction a
· simp
· simp only [← coe_sub, NNReal.sub_def, Real.coe_toNNReal', coe_toReal]
exact le_max_left _ _
#align ennreal.le_to_real_sub ENNReal.le_toReal_sub
theorem toReal_add_le : (a + b).toReal ≤ a.toReal + b.toReal :=
if ha : a = ∞ then by simp only [ha, top_add, top_toReal, zero_add, toReal_nonneg]
else
if hb : b = ∞ then by simp only [hb, add_top, top_toReal, add_zero, toReal_nonneg]
else le_of_eq (toReal_add ha hb)
#align ennreal.to_real_add_le ENNReal.toReal_add_le
theorem ofReal_add {p q : ℝ} (hp : 0 ≤ p) (hq : 0 ≤ q) :
ENNReal.ofReal (p + q) = ENNReal.ofReal p + ENNReal.ofReal q := by
rw [ENNReal.ofReal, ENNReal.ofReal, ENNReal.ofReal, ← coe_add, coe_inj,
Real.toNNReal_add hp hq]
#align ennreal.of_real_add ENNReal.ofReal_add
theorem ofReal_add_le {p q : ℝ} : ENNReal.ofReal (p + q) ≤ ENNReal.ofReal p + ENNReal.ofReal q :=
coe_le_coe.2 Real.toNNReal_add_le
#align ennreal.of_real_add_le ENNReal.ofReal_add_le
@[simp]
theorem toReal_le_toReal (ha : a ≠ ∞) (hb : b ≠ ∞) : a.toReal ≤ b.toReal ↔ a ≤ b := by
lift a to ℝ≥0 using ha
lift b to ℝ≥0 using hb
norm_cast
#align ennreal.to_real_le_to_real ENNReal.toReal_le_toReal
@[gcongr]
theorem toReal_mono (hb : b ≠ ∞) (h : a ≤ b) : a.toReal ≤ b.toReal :=
(toReal_le_toReal (ne_top_of_le_ne_top hb h) hb).2 h
#align ennreal.to_real_mono ENNReal.toReal_mono
-- Porting note (#10756): new lemma
theorem toReal_mono' (h : a ≤ b) (ht : b = ∞ → a = ∞) : a.toReal ≤ b.toReal := by
rcases eq_or_ne a ∞ with rfl | ha
· exact toReal_nonneg
· exact toReal_mono (mt ht ha) h
@[simp]
theorem toReal_lt_toReal (ha : a ≠ ∞) (hb : b ≠ ∞) : a.toReal < b.toReal ↔ a < b := by
lift a to ℝ≥0 using ha
lift b to ℝ≥0 using hb
norm_cast
#align ennreal.to_real_lt_to_real ENNReal.toReal_lt_toReal
@[gcongr]
theorem toReal_strict_mono (hb : b ≠ ∞) (h : a < b) : a.toReal < b.toReal :=
(toReal_lt_toReal h.ne_top hb).2 h
#align ennreal.to_real_strict_mono ENNReal.toReal_strict_mono
@[gcongr]
theorem toNNReal_mono (hb : b ≠ ∞) (h : a ≤ b) : a.toNNReal ≤ b.toNNReal :=
toReal_mono hb h
#align ennreal.to_nnreal_mono ENNReal.toNNReal_mono
-- Porting note (#10756): new lemma
theorem toReal_le_add' (hle : a ≤ b + c) (hb : b = ∞ → a = ∞) (hc : c = ∞ → a = ∞) :
a.toReal ≤ b.toReal + c.toReal := by
refine le_trans (toReal_mono' hle ?_) toReal_add_le
simpa only [add_eq_top, or_imp] using And.intro hb hc
-- Porting note (#10756): new lemma
theorem toReal_le_add (hle : a ≤ b + c) (hb : b ≠ ∞) (hc : c ≠ ∞) :
a.toReal ≤ b.toReal + c.toReal :=
toReal_le_add' hle (flip absurd hb) (flip absurd hc)
@[simp]
theorem toNNReal_le_toNNReal (ha : a ≠ ∞) (hb : b ≠ ∞) : a.toNNReal ≤ b.toNNReal ↔ a ≤ b :=
⟨fun h => by rwa [← coe_toNNReal ha, ← coe_toNNReal hb, coe_le_coe], toNNReal_mono hb⟩
#align ennreal.to_nnreal_le_to_nnreal ENNReal.toNNReal_le_toNNReal
theorem toNNReal_strict_mono (hb : b ≠ ∞) (h : a < b) : a.toNNReal < b.toNNReal := by
simpa [← ENNReal.coe_lt_coe, hb, h.ne_top]
#align ennreal.to_nnreal_strict_mono ENNReal.toNNReal_strict_mono
@[simp]
theorem toNNReal_lt_toNNReal (ha : a ≠ ∞) (hb : b ≠ ∞) : a.toNNReal < b.toNNReal ↔ a < b :=
⟨fun h => by rwa [← coe_toNNReal ha, ← coe_toNNReal hb, coe_lt_coe], toNNReal_strict_mono hb⟩
#align ennreal.to_nnreal_lt_to_nnreal ENNReal.toNNReal_lt_toNNReal
theorem toReal_max (hr : a ≠ ∞) (hp : b ≠ ∞) :
ENNReal.toReal (max a b) = max (ENNReal.toReal a) (ENNReal.toReal b) :=
(le_total a b).elim
(fun h => by simp only [h, (ENNReal.toReal_le_toReal hr hp).2 h, max_eq_right]) fun h => by
simp only [h, (ENNReal.toReal_le_toReal hp hr).2 h, max_eq_left]
#align ennreal.to_real_max ENNReal.toReal_max
theorem toReal_min {a b : ℝ≥0∞} (hr : a ≠ ∞) (hp : b ≠ ∞) :
ENNReal.toReal (min a b) = min (ENNReal.toReal a) (ENNReal.toReal b) :=
(le_total a b).elim (fun h => by simp only [h, (ENNReal.toReal_le_toReal hr hp).2 h, min_eq_left])
fun h => by simp only [h, (ENNReal.toReal_le_toReal hp hr).2 h, min_eq_right]
#align ennreal.to_real_min ENNReal.toReal_min
theorem toReal_sup {a b : ℝ≥0∞} : a ≠ ∞ → b ≠ ∞ → (a ⊔ b).toReal = a.toReal ⊔ b.toReal :=
toReal_max
#align ennreal.to_real_sup ENNReal.toReal_sup
theorem toReal_inf {a b : ℝ≥0∞} : a ≠ ∞ → b ≠ ∞ → (a ⊓ b).toReal = a.toReal ⊓ b.toReal :=
toReal_min
#align ennreal.to_real_inf ENNReal.toReal_inf
theorem toNNReal_pos_iff : 0 < a.toNNReal ↔ 0 < a ∧ a < ∞ := by
induction a <;> simp
#align ennreal.to_nnreal_pos_iff ENNReal.toNNReal_pos_iff
theorem toNNReal_pos {a : ℝ≥0∞} (ha₀ : a ≠ 0) (ha_top : a ≠ ∞) : 0 < a.toNNReal :=
toNNReal_pos_iff.mpr ⟨bot_lt_iff_ne_bot.mpr ha₀, lt_top_iff_ne_top.mpr ha_top⟩
#align ennreal.to_nnreal_pos ENNReal.toNNReal_pos
theorem toReal_pos_iff : 0 < a.toReal ↔ 0 < a ∧ a < ∞ :=
NNReal.coe_pos.trans toNNReal_pos_iff
#align ennreal.to_real_pos_iff ENNReal.toReal_pos_iff
theorem toReal_pos {a : ℝ≥0∞} (ha₀ : a ≠ 0) (ha_top : a ≠ ∞) : 0 < a.toReal :=
toReal_pos_iff.mpr ⟨bot_lt_iff_ne_bot.mpr ha₀, lt_top_iff_ne_top.mpr ha_top⟩
#align ennreal.to_real_pos ENNReal.toReal_pos
@[gcongr]
theorem ofReal_le_ofReal {p q : ℝ} (h : p ≤ q) : ENNReal.ofReal p ≤ ENNReal.ofReal q := by
simp [ENNReal.ofReal, Real.toNNReal_le_toNNReal h]
#align ennreal.of_real_le_of_real ENNReal.ofReal_le_ofReal
theorem ofReal_le_of_le_toReal {a : ℝ} {b : ℝ≥0∞} (h : a ≤ ENNReal.toReal b) :
ENNReal.ofReal a ≤ b :=
(ofReal_le_ofReal h).trans ofReal_toReal_le
#align ennreal.of_real_le_of_le_to_real ENNReal.ofReal_le_of_le_toReal
@[simp]
theorem ofReal_le_ofReal_iff {p q : ℝ} (h : 0 ≤ q) :
ENNReal.ofReal p ≤ ENNReal.ofReal q ↔ p ≤ q := by
rw [ENNReal.ofReal, ENNReal.ofReal, coe_le_coe, Real.toNNReal_le_toNNReal_iff h]
#align ennreal.of_real_le_of_real_iff ENNReal.ofReal_le_ofReal_iff
lemma ofReal_le_ofReal_iff' {p q : ℝ} : ENNReal.ofReal p ≤ .ofReal q ↔ p ≤ q ∨ p ≤ 0 :=
coe_le_coe.trans Real.toNNReal_le_toNNReal_iff'
lemma ofReal_lt_ofReal_iff' {p q : ℝ} : ENNReal.ofReal p < .ofReal q ↔ p < q ∧ 0 < q :=
coe_lt_coe.trans Real.toNNReal_lt_toNNReal_iff'
@[simp]
theorem ofReal_eq_ofReal_iff {p q : ℝ} (hp : 0 ≤ p) (hq : 0 ≤ q) :
ENNReal.ofReal p = ENNReal.ofReal q ↔ p = q := by
rw [ENNReal.ofReal, ENNReal.ofReal, coe_inj, Real.toNNReal_eq_toNNReal_iff hp hq]
#align ennreal.of_real_eq_of_real_iff ENNReal.ofReal_eq_ofReal_iff
@[simp]
theorem ofReal_lt_ofReal_iff {p q : ℝ} (h : 0 < q) :
ENNReal.ofReal p < ENNReal.ofReal q ↔ p < q := by
rw [ENNReal.ofReal, ENNReal.ofReal, coe_lt_coe, Real.toNNReal_lt_toNNReal_iff h]
#align ennreal.of_real_lt_of_real_iff ENNReal.ofReal_lt_ofReal_iff
theorem ofReal_lt_ofReal_iff_of_nonneg {p q : ℝ} (hp : 0 ≤ p) :
ENNReal.ofReal p < ENNReal.ofReal q ↔ p < q := by
rw [ENNReal.ofReal, ENNReal.ofReal, coe_lt_coe, Real.toNNReal_lt_toNNReal_iff_of_nonneg hp]
#align ennreal.of_real_lt_of_real_iff_of_nonneg ENNReal.ofReal_lt_ofReal_iff_of_nonneg
@[simp]
theorem ofReal_pos {p : ℝ} : 0 < ENNReal.ofReal p ↔ 0 < p := by simp [ENNReal.ofReal]
#align ennreal.of_real_pos ENNReal.ofReal_pos
@[simp]
theorem ofReal_eq_zero {p : ℝ} : ENNReal.ofReal p = 0 ↔ p ≤ 0 := by simp [ENNReal.ofReal]
#align ennreal.of_real_eq_zero ENNReal.ofReal_eq_zero
@[simp]
theorem zero_eq_ofReal {p : ℝ} : 0 = ENNReal.ofReal p ↔ p ≤ 0 :=
eq_comm.trans ofReal_eq_zero
#align ennreal.zero_eq_of_real ENNReal.zero_eq_ofReal
alias ⟨_, ofReal_of_nonpos⟩ := ofReal_eq_zero
#align ennreal.of_real_of_nonpos ENNReal.ofReal_of_nonpos
@[simp]
lemma ofReal_lt_natCast {p : ℝ} {n : ℕ} (hn : n ≠ 0) : ENNReal.ofReal p < n ↔ p < n := by
exact mod_cast ofReal_lt_ofReal_iff (Nat.cast_pos.2 hn.bot_lt)
@[deprecated (since := "2024-04-17")]
alias ofReal_lt_nat_cast := ofReal_lt_natCast
@[simp]
lemma ofReal_lt_one {p : ℝ} : ENNReal.ofReal p < 1 ↔ p < 1 := by
exact mod_cast ofReal_lt_natCast one_ne_zero
@[simp]
lemma ofReal_lt_ofNat {p : ℝ} {n : ℕ} [n.AtLeastTwo] :
ENNReal.ofReal p < no_index (OfNat.ofNat n) ↔ p < OfNat.ofNat n :=
ofReal_lt_natCast (NeZero.ne n)
@[simp]
lemma natCast_le_ofReal {n : ℕ} {p : ℝ} (hn : n ≠ 0) : n ≤ ENNReal.ofReal p ↔ n ≤ p := by
simp only [← not_lt, ofReal_lt_natCast hn]
@[deprecated (since := "2024-04-17")]
alias nat_cast_le_ofReal := natCast_le_ofReal
@[simp]
lemma one_le_ofReal {p : ℝ} : 1 ≤ ENNReal.ofReal p ↔ 1 ≤ p := by
exact mod_cast natCast_le_ofReal one_ne_zero
@[simp]
lemma ofNat_le_ofReal {n : ℕ} [n.AtLeastTwo] {p : ℝ} :
no_index (OfNat.ofNat n) ≤ ENNReal.ofReal p ↔ OfNat.ofNat n ≤ p :=
natCast_le_ofReal (NeZero.ne n)
@[simp]
lemma ofReal_le_natCast {r : ℝ} {n : ℕ} : ENNReal.ofReal r ≤ n ↔ r ≤ n :=
coe_le_coe.trans Real.toNNReal_le_natCast
@[deprecated (since := "2024-04-17")]
alias ofReal_le_nat_cast := ofReal_le_natCast
@[simp]
lemma ofReal_le_one {r : ℝ} : ENNReal.ofReal r ≤ 1 ↔ r ≤ 1 :=
coe_le_coe.trans Real.toNNReal_le_one
@[simp]
lemma ofReal_le_ofNat {r : ℝ} {n : ℕ} [n.AtLeastTwo] :
ENNReal.ofReal r ≤ no_index (OfNat.ofNat n) ↔ r ≤ OfNat.ofNat n :=
ofReal_le_natCast
@[simp]
lemma natCast_lt_ofReal {n : ℕ} {r : ℝ} : n < ENNReal.ofReal r ↔ n < r :=
coe_lt_coe.trans Real.natCast_lt_toNNReal
@[deprecated (since := "2024-04-17")]
alias nat_cast_lt_ofReal := natCast_lt_ofReal
@[simp]
lemma one_lt_ofReal {r : ℝ} : 1 < ENNReal.ofReal r ↔ 1 < r := coe_lt_coe.trans Real.one_lt_toNNReal
@[simp]
lemma ofNat_lt_ofReal {n : ℕ} [n.AtLeastTwo] {r : ℝ} :
no_index (OfNat.ofNat n) < ENNReal.ofReal r ↔ OfNat.ofNat n < r :=
natCast_lt_ofReal
@[simp]
lemma ofReal_eq_natCast {r : ℝ} {n : ℕ} (h : n ≠ 0) : ENNReal.ofReal r = n ↔ r = n :=
ENNReal.coe_inj.trans <| Real.toNNReal_eq_natCast h
@[deprecated (since := "2024-04-17")]
alias ofReal_eq_nat_cast := ofReal_eq_natCast
@[simp]
lemma ofReal_eq_one {r : ℝ} : ENNReal.ofReal r = 1 ↔ r = 1 :=
ENNReal.coe_inj.trans Real.toNNReal_eq_one
@[simp]
lemma ofReal_eq_ofNat {r : ℝ} {n : ℕ} [n.AtLeastTwo] :
ENNReal.ofReal r = no_index (OfNat.ofNat n) ↔ r = OfNat.ofNat n :=
ofReal_eq_natCast (NeZero.ne n)
theorem ofReal_sub (p : ℝ) {q : ℝ} (hq : 0 ≤ q) :
ENNReal.ofReal (p - q) = ENNReal.ofReal p - ENNReal.ofReal q := by
obtain h | h := le_total p q
· rw [ofReal_of_nonpos (sub_nonpos_of_le h), tsub_eq_zero_of_le (ofReal_le_ofReal h)]
refine ENNReal.eq_sub_of_add_eq ofReal_ne_top ?_
rw [← ofReal_add (sub_nonneg_of_le h) hq, sub_add_cancel]
#align ennreal.of_real_sub ENNReal.ofReal_sub
theorem ofReal_le_iff_le_toReal {a : ℝ} {b : ℝ≥0∞} (hb : b ≠ ∞) :
ENNReal.ofReal a ≤ b ↔ a ≤ ENNReal.toReal b := by
lift b to ℝ≥0 using hb
simpa [ENNReal.ofReal, ENNReal.toReal] using Real.toNNReal_le_iff_le_coe
#align ennreal.of_real_le_iff_le_to_real ENNReal.ofReal_le_iff_le_toReal
theorem ofReal_lt_iff_lt_toReal {a : ℝ} {b : ℝ≥0∞} (ha : 0 ≤ a) (hb : b ≠ ∞) :
ENNReal.ofReal a < b ↔ a < ENNReal.toReal b := by
lift b to ℝ≥0 using hb
simpa [ENNReal.ofReal, ENNReal.toReal] using Real.toNNReal_lt_iff_lt_coe ha
#align ennreal.of_real_lt_iff_lt_to_real ENNReal.ofReal_lt_iff_lt_toReal
theorem ofReal_lt_coe_iff {a : ℝ} {b : ℝ≥0} (ha : 0 ≤ a) : ENNReal.ofReal a < b ↔ a < b :=
(ofReal_lt_iff_lt_toReal ha coe_ne_top).trans <| by rw [coe_toReal]
theorem le_ofReal_iff_toReal_le {a : ℝ≥0∞} {b : ℝ} (ha : a ≠ ∞) (hb : 0 ≤ b) :
a ≤ ENNReal.ofReal b ↔ ENNReal.toReal a ≤ b := by
lift a to ℝ≥0 using ha
simpa [ENNReal.ofReal, ENNReal.toReal] using Real.le_toNNReal_iff_coe_le hb
#align ennreal.le_of_real_iff_to_real_le ENNReal.le_ofReal_iff_toReal_le
theorem toReal_le_of_le_ofReal {a : ℝ≥0∞} {b : ℝ} (hb : 0 ≤ b) (h : a ≤ ENNReal.ofReal b) :
ENNReal.toReal a ≤ b :=
have ha : a ≠ ∞ := ne_top_of_le_ne_top ofReal_ne_top h
(le_ofReal_iff_toReal_le ha hb).1 h
#align ennreal.to_real_le_of_le_of_real ENNReal.toReal_le_of_le_ofReal
theorem lt_ofReal_iff_toReal_lt {a : ℝ≥0∞} {b : ℝ} (ha : a ≠ ∞) :
a < ENNReal.ofReal b ↔ ENNReal.toReal a < b := by
lift a to ℝ≥0 using ha
simpa [ENNReal.ofReal, ENNReal.toReal] using Real.lt_toNNReal_iff_coe_lt
#align ennreal.lt_of_real_iff_to_real_lt ENNReal.lt_ofReal_iff_toReal_lt
theorem toReal_lt_of_lt_ofReal {b : ℝ} (h : a < ENNReal.ofReal b) : ENNReal.toReal a < b :=
(lt_ofReal_iff_toReal_lt h.ne_top).1 h
| Mathlib/Data/ENNReal/Real.lean | 356 | 358 | theorem ofReal_mul {p q : ℝ} (hp : 0 ≤ p) :
ENNReal.ofReal (p * q) = ENNReal.ofReal p * ENNReal.ofReal q := by |
simp only [ENNReal.ofReal, ← coe_mul, Real.toNNReal_mul hp]
|
import Mathlib.Probability.Variance
#align_import probability.moments from "leanprover-community/mathlib"@"85453a2a14be8da64caf15ca50930cf4c6e5d8de"
open MeasureTheory Filter Finset Real
noncomputable section
open scoped MeasureTheory ProbabilityTheory ENNReal NNReal
namespace ProbabilityTheory
variable {Ω ι : Type*} {m : MeasurableSpace Ω} {X : Ω → ℝ} {p : ℕ} {μ : Measure Ω}
def moment (X : Ω → ℝ) (p : ℕ) (μ : Measure Ω) : ℝ :=
μ[X ^ p]
#align probability_theory.moment ProbabilityTheory.moment
def centralMoment (X : Ω → ℝ) (p : ℕ) (μ : Measure Ω) : ℝ := by
have m := fun (x : Ω) => μ[X] -- Porting note: Lean deems `μ[(X - fun x => μ[X]) ^ p]` ambiguous
exact μ[(X - m) ^ p]
#align probability_theory.central_moment ProbabilityTheory.centralMoment
@[simp]
theorem moment_zero (hp : p ≠ 0) : moment 0 p μ = 0 := by
simp only [moment, hp, zero_pow, Ne, not_false_iff, Pi.zero_apply, integral_const,
smul_eq_mul, mul_zero, integral_zero]
#align probability_theory.moment_zero ProbabilityTheory.moment_zero
@[simp]
theorem centralMoment_zero (hp : p ≠ 0) : centralMoment 0 p μ = 0 := by
simp only [centralMoment, hp, Pi.zero_apply, integral_const, smul_eq_mul,
mul_zero, zero_sub, Pi.pow_apply, Pi.neg_apply, neg_zero, zero_pow, Ne, not_false_iff]
#align probability_theory.central_moment_zero ProbabilityTheory.centralMoment_zero
theorem centralMoment_one' [IsFiniteMeasure μ] (h_int : Integrable X μ) :
centralMoment X 1 μ = (1 - (μ Set.univ).toReal) * μ[X] := by
simp only [centralMoment, Pi.sub_apply, pow_one]
rw [integral_sub h_int (integrable_const _)]
simp only [sub_mul, integral_const, smul_eq_mul, one_mul]
#align probability_theory.central_moment_one' ProbabilityTheory.centralMoment_one'
@[simp]
theorem centralMoment_one [IsProbabilityMeasure μ] : centralMoment X 1 μ = 0 := by
by_cases h_int : Integrable X μ
· rw [centralMoment_one' h_int]
simp only [measure_univ, ENNReal.one_toReal, sub_self, zero_mul]
· simp only [centralMoment, Pi.sub_apply, pow_one]
have : ¬Integrable (fun x => X x - integral μ X) μ := by
refine fun h_sub => h_int ?_
have h_add : X = (fun x => X x - integral μ X) + fun _ => integral μ X := by ext1 x; simp
rw [h_add]
exact h_sub.add (integrable_const _)
rw [integral_undef this]
#align probability_theory.central_moment_one ProbabilityTheory.centralMoment_one
theorem centralMoment_two_eq_variance [IsFiniteMeasure μ] (hX : Memℒp X 2 μ) :
centralMoment X 2 μ = variance X μ := by rw [hX.variance_eq]; rfl
#align probability_theory.central_moment_two_eq_variance ProbabilityTheory.centralMoment_two_eq_variance
section MomentGeneratingFunction
variable {t : ℝ}
def mgf (X : Ω → ℝ) (μ : Measure Ω) (t : ℝ) : ℝ :=
μ[fun ω => exp (t * X ω)]
#align probability_theory.mgf ProbabilityTheory.mgf
def cgf (X : Ω → ℝ) (μ : Measure Ω) (t : ℝ) : ℝ :=
log (mgf X μ t)
#align probability_theory.cgf ProbabilityTheory.cgf
@[simp]
theorem mgf_zero_fun : mgf 0 μ t = (μ Set.univ).toReal := by
simp only [mgf, Pi.zero_apply, mul_zero, exp_zero, integral_const, smul_eq_mul, mul_one]
#align probability_theory.mgf_zero_fun ProbabilityTheory.mgf_zero_fun
@[simp]
theorem cgf_zero_fun : cgf 0 μ t = log (μ Set.univ).toReal := by simp only [cgf, mgf_zero_fun]
#align probability_theory.cgf_zero_fun ProbabilityTheory.cgf_zero_fun
@[simp]
theorem mgf_zero_measure : mgf X (0 : Measure Ω) t = 0 := by simp only [mgf, integral_zero_measure]
#align probability_theory.mgf_zero_measure ProbabilityTheory.mgf_zero_measure
@[simp]
theorem cgf_zero_measure : cgf X (0 : Measure Ω) t = 0 := by
simp only [cgf, log_zero, mgf_zero_measure]
#align probability_theory.cgf_zero_measure ProbabilityTheory.cgf_zero_measure
@[simp]
theorem mgf_const' (c : ℝ) : mgf (fun _ => c) μ t = (μ Set.univ).toReal * exp (t * c) := by
simp only [mgf, integral_const, smul_eq_mul]
#align probability_theory.mgf_const' ProbabilityTheory.mgf_const'
-- @[simp] -- Porting note: `simp only` already proves this
theorem mgf_const (c : ℝ) [IsProbabilityMeasure μ] : mgf (fun _ => c) μ t = exp (t * c) := by
simp only [mgf_const', measure_univ, ENNReal.one_toReal, one_mul]
#align probability_theory.mgf_const ProbabilityTheory.mgf_const
@[simp]
theorem cgf_const' [IsFiniteMeasure μ] (hμ : μ ≠ 0) (c : ℝ) :
cgf (fun _ => c) μ t = log (μ Set.univ).toReal + t * c := by
simp only [cgf, mgf_const']
rw [log_mul _ (exp_pos _).ne']
· rw [log_exp _]
· rw [Ne, ENNReal.toReal_eq_zero_iff, Measure.measure_univ_eq_zero]
simp only [hμ, measure_ne_top μ Set.univ, or_self_iff, not_false_iff]
#align probability_theory.cgf_const' ProbabilityTheory.cgf_const'
@[simp]
theorem cgf_const [IsProbabilityMeasure μ] (c : ℝ) : cgf (fun _ => c) μ t = t * c := by
simp only [cgf, mgf_const, log_exp]
#align probability_theory.cgf_const ProbabilityTheory.cgf_const
@[simp]
theorem mgf_zero' : mgf X μ 0 = (μ Set.univ).toReal := by
simp only [mgf, zero_mul, exp_zero, integral_const, smul_eq_mul, mul_one]
#align probability_theory.mgf_zero' ProbabilityTheory.mgf_zero'
-- @[simp] -- Porting note: `simp only` already proves this
theorem mgf_zero [IsProbabilityMeasure μ] : mgf X μ 0 = 1 := by
simp only [mgf_zero', measure_univ, ENNReal.one_toReal]
#align probability_theory.mgf_zero ProbabilityTheory.mgf_zero
@[simp]
theorem cgf_zero' : cgf X μ 0 = log (μ Set.univ).toReal := by simp only [cgf, mgf_zero']
#align probability_theory.cgf_zero' ProbabilityTheory.cgf_zero'
-- @[simp] -- Porting note: `simp only` already proves this
theorem cgf_zero [IsProbabilityMeasure μ] : cgf X μ 0 = 0 := by
simp only [cgf_zero', measure_univ, ENNReal.one_toReal, log_one]
#align probability_theory.cgf_zero ProbabilityTheory.cgf_zero
theorem mgf_undef (hX : ¬Integrable (fun ω => exp (t * X ω)) μ) : mgf X μ t = 0 := by
simp only [mgf, integral_undef hX]
#align probability_theory.mgf_undef ProbabilityTheory.mgf_undef
theorem cgf_undef (hX : ¬Integrable (fun ω => exp (t * X ω)) μ) : cgf X μ t = 0 := by
simp only [cgf, mgf_undef hX, log_zero]
#align probability_theory.cgf_undef ProbabilityTheory.cgf_undef
theorem mgf_nonneg : 0 ≤ mgf X μ t := by
unfold mgf; positivity
#align probability_theory.mgf_nonneg ProbabilityTheory.mgf_nonneg
| Mathlib/Probability/Moments.lean | 186 | 202 | theorem mgf_pos' (hμ : μ ≠ 0) (h_int_X : Integrable (fun ω => exp (t * X ω)) μ) :
0 < mgf X μ t := by |
simp_rw [mgf]
have : ∫ x : Ω, exp (t * X x) ∂μ = ∫ x : Ω in Set.univ, exp (t * X x) ∂μ := by
simp only [Measure.restrict_univ]
rw [this, setIntegral_pos_iff_support_of_nonneg_ae _ _]
· have h_eq_univ : (Function.support fun x : Ω => exp (t * X x)) = Set.univ := by
ext1 x
simp only [Function.mem_support, Set.mem_univ, iff_true_iff]
exact (exp_pos _).ne'
rw [h_eq_univ, Set.inter_univ _]
refine Ne.bot_lt ?_
simp only [hμ, ENNReal.bot_eq_zero, Ne, Measure.measure_univ_eq_zero, not_false_iff]
· filter_upwards with x
rw [Pi.zero_apply]
exact (exp_pos _).le
· rwa [integrableOn_univ]
|
import Mathlib.Topology.Compactness.SigmaCompact
import Mathlib.Topology.Connected.TotallyDisconnected
import Mathlib.Topology.Inseparable
#align_import topology.separation from "leanprover-community/mathlib"@"d91e7f7a7f1c7e9f0e18fdb6bde4f652004c735d"
open Function Set Filter Topology TopologicalSpace
open scoped Classical
universe u v
variable {X : Type*} {Y : Type*} [TopologicalSpace X]
section Separation
def SeparatedNhds : Set X → Set X → Prop := fun s t : Set X =>
∃ U V : Set X, IsOpen U ∧ IsOpen V ∧ s ⊆ U ∧ t ⊆ V ∧ Disjoint U V
#align separated_nhds SeparatedNhds
theorem separatedNhds_iff_disjoint {s t : Set X} : SeparatedNhds s t ↔ Disjoint (𝓝ˢ s) (𝓝ˢ t) := by
simp only [(hasBasis_nhdsSet s).disjoint_iff (hasBasis_nhdsSet t), SeparatedNhds, exists_prop, ←
exists_and_left, and_assoc, and_comm, and_left_comm]
#align separated_nhds_iff_disjoint separatedNhds_iff_disjoint
alias ⟨SeparatedNhds.disjoint_nhdsSet, _⟩ := separatedNhds_iff_disjoint
class T0Space (X : Type u) [TopologicalSpace X] : Prop where
t0 : ∀ ⦃x y : X⦄, Inseparable x y → x = y
#align t0_space T0Space
theorem t0Space_iff_inseparable (X : Type u) [TopologicalSpace X] :
T0Space X ↔ ∀ x y : X, Inseparable x y → x = y :=
⟨fun ⟨h⟩ => h, fun h => ⟨h⟩⟩
#align t0_space_iff_inseparable t0Space_iff_inseparable
theorem t0Space_iff_not_inseparable (X : Type u) [TopologicalSpace X] :
T0Space X ↔ Pairwise fun x y : X => ¬Inseparable x y := by
simp only [t0Space_iff_inseparable, Ne, not_imp_not, Pairwise]
#align t0_space_iff_not_inseparable t0Space_iff_not_inseparable
theorem Inseparable.eq [T0Space X] {x y : X} (h : Inseparable x y) : x = y :=
T0Space.t0 h
#align inseparable.eq Inseparable.eq
protected theorem Inducing.injective [TopologicalSpace Y] [T0Space X] {f : X → Y}
(hf : Inducing f) : Injective f := fun _ _ h =>
(hf.inseparable_iff.1 <| .of_eq h).eq
#align inducing.injective Inducing.injective
protected theorem Inducing.embedding [TopologicalSpace Y] [T0Space X] {f : X → Y}
(hf : Inducing f) : Embedding f :=
⟨hf, hf.injective⟩
#align inducing.embedding Inducing.embedding
lemma embedding_iff_inducing [TopologicalSpace Y] [T0Space X] {f : X → Y} :
Embedding f ↔ Inducing f :=
⟨Embedding.toInducing, Inducing.embedding⟩
#align embedding_iff_inducing embedding_iff_inducing
theorem t0Space_iff_nhds_injective (X : Type u) [TopologicalSpace X] :
T0Space X ↔ Injective (𝓝 : X → Filter X) :=
t0Space_iff_inseparable X
#align t0_space_iff_nhds_injective t0Space_iff_nhds_injective
theorem nhds_injective [T0Space X] : Injective (𝓝 : X → Filter X) :=
(t0Space_iff_nhds_injective X).1 ‹_›
#align nhds_injective nhds_injective
theorem inseparable_iff_eq [T0Space X] {x y : X} : Inseparable x y ↔ x = y :=
nhds_injective.eq_iff
#align inseparable_iff_eq inseparable_iff_eq
@[simp]
theorem nhds_eq_nhds_iff [T0Space X] {a b : X} : 𝓝 a = 𝓝 b ↔ a = b :=
nhds_injective.eq_iff
#align nhds_eq_nhds_iff nhds_eq_nhds_iff
@[simp]
theorem inseparable_eq_eq [T0Space X] : Inseparable = @Eq X :=
funext₂ fun _ _ => propext inseparable_iff_eq
#align inseparable_eq_eq inseparable_eq_eq
theorem TopologicalSpace.IsTopologicalBasis.inseparable_iff {b : Set (Set X)}
(hb : IsTopologicalBasis b) {x y : X} : Inseparable x y ↔ ∀ s ∈ b, (x ∈ s ↔ y ∈ s) :=
⟨fun h s hs ↦ inseparable_iff_forall_open.1 h _ (hb.isOpen hs),
fun h ↦ hb.nhds_hasBasis.eq_of_same_basis <| by
convert hb.nhds_hasBasis using 2
exact and_congr_right (h _)⟩
theorem TopologicalSpace.IsTopologicalBasis.eq_iff [T0Space X] {b : Set (Set X)}
(hb : IsTopologicalBasis b) {x y : X} : x = y ↔ ∀ s ∈ b, (x ∈ s ↔ y ∈ s) :=
inseparable_iff_eq.symm.trans hb.inseparable_iff
theorem t0Space_iff_exists_isOpen_xor'_mem (X : Type u) [TopologicalSpace X] :
T0Space X ↔ Pairwise fun x y => ∃ U : Set X, IsOpen U ∧ Xor' (x ∈ U) (y ∈ U) := by
simp only [t0Space_iff_not_inseparable, xor_iff_not_iff, not_forall, exists_prop,
inseparable_iff_forall_open, Pairwise]
#align t0_space_iff_exists_is_open_xor_mem t0Space_iff_exists_isOpen_xor'_mem
theorem exists_isOpen_xor'_mem [T0Space X] {x y : X} (h : x ≠ y) :
∃ U : Set X, IsOpen U ∧ Xor' (x ∈ U) (y ∈ U) :=
(t0Space_iff_exists_isOpen_xor'_mem X).1 ‹_› h
#align exists_is_open_xor_mem exists_isOpen_xor'_mem
def specializationOrder (X) [TopologicalSpace X] [T0Space X] : PartialOrder X :=
{ specializationPreorder X, PartialOrder.lift (OrderDual.toDual ∘ 𝓝) nhds_injective with }
#align specialization_order specializationOrder
instance SeparationQuotient.instT0Space : T0Space (SeparationQuotient X) :=
⟨fun x y => Quotient.inductionOn₂' x y fun _ _ h =>
SeparationQuotient.mk_eq_mk.2 <| SeparationQuotient.inducing_mk.inseparable_iff.1 h⟩
theorem minimal_nonempty_closed_subsingleton [T0Space X] {s : Set X} (hs : IsClosed s)
(hmin : ∀ t, t ⊆ s → t.Nonempty → IsClosed t → t = s) : s.Subsingleton := by
clear Y -- Porting note: added
refine fun x hx y hy => of_not_not fun hxy => ?_
rcases exists_isOpen_xor'_mem hxy with ⟨U, hUo, hU⟩
wlog h : x ∈ U ∧ y ∉ U
· refine this hs hmin y hy x hx (Ne.symm hxy) U hUo hU.symm (hU.resolve_left h)
cases' h with hxU hyU
have : s \ U = s := hmin (s \ U) diff_subset ⟨y, hy, hyU⟩ (hs.sdiff hUo)
exact (this.symm.subset hx).2 hxU
#align minimal_nonempty_closed_subsingleton minimal_nonempty_closed_subsingleton
theorem minimal_nonempty_closed_eq_singleton [T0Space X] {s : Set X} (hs : IsClosed s)
(hne : s.Nonempty) (hmin : ∀ t, t ⊆ s → t.Nonempty → IsClosed t → t = s) : ∃ x, s = {x} :=
exists_eq_singleton_iff_nonempty_subsingleton.2
⟨hne, minimal_nonempty_closed_subsingleton hs hmin⟩
#align minimal_nonempty_closed_eq_singleton minimal_nonempty_closed_eq_singleton
theorem IsClosed.exists_closed_singleton [T0Space X] [CompactSpace X] {S : Set X}
(hS : IsClosed S) (hne : S.Nonempty) : ∃ x : X, x ∈ S ∧ IsClosed ({x} : Set X) := by
obtain ⟨V, Vsub, Vne, Vcls, hV⟩ := hS.exists_minimal_nonempty_closed_subset hne
rcases minimal_nonempty_closed_eq_singleton Vcls Vne hV with ⟨x, rfl⟩
exact ⟨x, Vsub (mem_singleton x), Vcls⟩
#align is_closed.exists_closed_singleton IsClosed.exists_closed_singleton
theorem minimal_nonempty_open_subsingleton [T0Space X] {s : Set X} (hs : IsOpen s)
(hmin : ∀ t, t ⊆ s → t.Nonempty → IsOpen t → t = s) : s.Subsingleton := by
clear Y -- Porting note: added
refine fun x hx y hy => of_not_not fun hxy => ?_
rcases exists_isOpen_xor'_mem hxy with ⟨U, hUo, hU⟩
wlog h : x ∈ U ∧ y ∉ U
· exact this hs hmin y hy x hx (Ne.symm hxy) U hUo hU.symm (hU.resolve_left h)
cases' h with hxU hyU
have : s ∩ U = s := hmin (s ∩ U) inter_subset_left ⟨x, hx, hxU⟩ (hs.inter hUo)
exact hyU (this.symm.subset hy).2
#align minimal_nonempty_open_subsingleton minimal_nonempty_open_subsingleton
theorem minimal_nonempty_open_eq_singleton [T0Space X] {s : Set X} (hs : IsOpen s)
(hne : s.Nonempty) (hmin : ∀ t, t ⊆ s → t.Nonempty → IsOpen t → t = s) : ∃ x, s = {x} :=
exists_eq_singleton_iff_nonempty_subsingleton.2 ⟨hne, minimal_nonempty_open_subsingleton hs hmin⟩
#align minimal_nonempty_open_eq_singleton minimal_nonempty_open_eq_singleton
theorem exists_isOpen_singleton_of_isOpen_finite [T0Space X] {s : Set X} (hfin : s.Finite)
(hne : s.Nonempty) (ho : IsOpen s) : ∃ x ∈ s, IsOpen ({x} : Set X) := by
lift s to Finset X using hfin
induction' s using Finset.strongInductionOn with s ihs
rcases em (∃ t, t ⊂ s ∧ t.Nonempty ∧ IsOpen (t : Set X)) with (⟨t, hts, htne, hto⟩ | ht)
· rcases ihs t hts htne hto with ⟨x, hxt, hxo⟩
exact ⟨x, hts.1 hxt, hxo⟩
· -- Porting note: was `rcases minimal_nonempty_open_eq_singleton ho hne _ with ⟨x, hx⟩`
-- https://github.com/leanprover/std4/issues/116
rsuffices ⟨x, hx⟩ : ∃ x, s.toSet = {x}
· exact ⟨x, hx.symm ▸ rfl, hx ▸ ho⟩
refine minimal_nonempty_open_eq_singleton ho hne ?_
refine fun t hts htne hto => of_not_not fun hts' => ht ?_
lift t to Finset X using s.finite_toSet.subset hts
exact ⟨t, ssubset_iff_subset_ne.2 ⟨hts, mt Finset.coe_inj.2 hts'⟩, htne, hto⟩
#align exists_open_singleton_of_open_finite exists_isOpen_singleton_of_isOpen_finite
theorem exists_open_singleton_of_finite [T0Space X] [Finite X] [Nonempty X] :
∃ x : X, IsOpen ({x} : Set X) :=
let ⟨x, _, h⟩ := exists_isOpen_singleton_of_isOpen_finite (Set.toFinite _)
univ_nonempty isOpen_univ
⟨x, h⟩
#align exists_open_singleton_of_fintype exists_open_singleton_of_finite
theorem t0Space_of_injective_of_continuous [TopologicalSpace Y] {f : X → Y}
(hf : Function.Injective f) (hf' : Continuous f) [T0Space Y] : T0Space X :=
⟨fun _ _ h => hf <| (h.map hf').eq⟩
#align t0_space_of_injective_of_continuous t0Space_of_injective_of_continuous
protected theorem Embedding.t0Space [TopologicalSpace Y] [T0Space Y] {f : X → Y}
(hf : Embedding f) : T0Space X :=
t0Space_of_injective_of_continuous hf.inj hf.continuous
#align embedding.t0_space Embedding.t0Space
instance Subtype.t0Space [T0Space X] {p : X → Prop} : T0Space (Subtype p) :=
embedding_subtype_val.t0Space
#align subtype.t0_space Subtype.t0Space
theorem t0Space_iff_or_not_mem_closure (X : Type u) [TopologicalSpace X] :
T0Space X ↔ Pairwise fun a b : X => a ∉ closure ({b} : Set X) ∨ b ∉ closure ({a} : Set X) := by
simp only [t0Space_iff_not_inseparable, inseparable_iff_mem_closure, not_and_or]
#align t0_space_iff_or_not_mem_closure t0Space_iff_or_not_mem_closure
instance Prod.instT0Space [TopologicalSpace Y] [T0Space X] [T0Space Y] : T0Space (X × Y) :=
⟨fun _ _ h => Prod.ext (h.map continuous_fst).eq (h.map continuous_snd).eq⟩
instance Pi.instT0Space {ι : Type*} {X : ι → Type*} [∀ i, TopologicalSpace (X i)]
[∀ i, T0Space (X i)] :
T0Space (∀ i, X i) :=
⟨fun _ _ h => funext fun i => (h.map (continuous_apply i)).eq⟩
#align pi.t0_space Pi.instT0Space
instance ULift.instT0Space [T0Space X] : T0Space (ULift X) :=
embedding_uLift_down.t0Space
theorem T0Space.of_cover (h : ∀ x y, Inseparable x y → ∃ s : Set X, x ∈ s ∧ y ∈ s ∧ T0Space s) :
T0Space X := by
refine ⟨fun x y hxy => ?_⟩
rcases h x y hxy with ⟨s, hxs, hys, hs⟩
lift x to s using hxs; lift y to s using hys
rw [← subtype_inseparable_iff] at hxy
exact congr_arg Subtype.val hxy.eq
#align t0_space.of_cover T0Space.of_cover
theorem T0Space.of_open_cover (h : ∀ x, ∃ s : Set X, x ∈ s ∧ IsOpen s ∧ T0Space s) : T0Space X :=
T0Space.of_cover fun x _ hxy =>
let ⟨s, hxs, hso, hs⟩ := h x
⟨s, hxs, (hxy.mem_open_iff hso).1 hxs, hs⟩
#align t0_space.of_open_cover T0Space.of_open_cover
@[mk_iff]
class R0Space (X : Type u) [TopologicalSpace X] : Prop where
specializes_symmetric : Symmetric (Specializes : X → X → Prop)
export R0Space (specializes_symmetric)
class T1Space (X : Type u) [TopologicalSpace X] : Prop where
t1 : ∀ x, IsClosed ({x} : Set X)
#align t1_space T1Space
theorem isClosed_singleton [T1Space X] {x : X} : IsClosed ({x} : Set X) :=
T1Space.t1 x
#align is_closed_singleton isClosed_singleton
theorem isOpen_compl_singleton [T1Space X] {x : X} : IsOpen ({x}ᶜ : Set X) :=
isClosed_singleton.isOpen_compl
#align is_open_compl_singleton isOpen_compl_singleton
theorem isOpen_ne [T1Space X] {x : X} : IsOpen { y | y ≠ x } :=
isOpen_compl_singleton
#align is_open_ne isOpen_ne
@[to_additive]
theorem Continuous.isOpen_mulSupport [T1Space X] [One X] [TopologicalSpace Y] {f : Y → X}
(hf : Continuous f) : IsOpen (mulSupport f) :=
isOpen_ne.preimage hf
#align continuous.is_open_mul_support Continuous.isOpen_mulSupport
#align continuous.is_open_support Continuous.isOpen_support
theorem Ne.nhdsWithin_compl_singleton [T1Space X] {x y : X} (h : x ≠ y) : 𝓝[{y}ᶜ] x = 𝓝 x :=
isOpen_ne.nhdsWithin_eq h
#align ne.nhds_within_compl_singleton Ne.nhdsWithin_compl_singleton
theorem Ne.nhdsWithin_diff_singleton [T1Space X] {x y : X} (h : x ≠ y) (s : Set X) :
𝓝[s \ {y}] x = 𝓝[s] x := by
rw [diff_eq, inter_comm, nhdsWithin_inter_of_mem]
exact mem_nhdsWithin_of_mem_nhds (isOpen_ne.mem_nhds h)
#align ne.nhds_within_diff_singleton Ne.nhdsWithin_diff_singleton
lemma nhdsWithin_compl_singleton_le [T1Space X] (x y : X) : 𝓝[{x}ᶜ] x ≤ 𝓝[{y}ᶜ] x := by
rcases eq_or_ne x y with rfl|hy
· exact Eq.le rfl
· rw [Ne.nhdsWithin_compl_singleton hy]
exact nhdsWithin_le_nhds
theorem isOpen_setOf_eventually_nhdsWithin [T1Space X] {p : X → Prop} :
IsOpen { x | ∀ᶠ y in 𝓝[≠] x, p y } := by
refine isOpen_iff_mem_nhds.mpr fun a ha => ?_
filter_upwards [eventually_nhds_nhdsWithin.mpr ha] with b hb
rcases eq_or_ne a b with rfl | h
· exact hb
· rw [h.symm.nhdsWithin_compl_singleton] at hb
exact hb.filter_mono nhdsWithin_le_nhds
#align is_open_set_of_eventually_nhds_within isOpen_setOf_eventually_nhdsWithin
protected theorem Set.Finite.isClosed [T1Space X] {s : Set X} (hs : Set.Finite s) : IsClosed s := by
rw [← biUnion_of_singleton s]
exact hs.isClosed_biUnion fun i _ => isClosed_singleton
#align set.finite.is_closed Set.Finite.isClosed
theorem TopologicalSpace.IsTopologicalBasis.exists_mem_of_ne [T1Space X] {b : Set (Set X)}
(hb : IsTopologicalBasis b) {x y : X} (h : x ≠ y) : ∃ a ∈ b, x ∈ a ∧ y ∉ a := by
rcases hb.isOpen_iff.1 isOpen_ne x h with ⟨a, ab, xa, ha⟩
exact ⟨a, ab, xa, fun h => ha h rfl⟩
#align topological_space.is_topological_basis.exists_mem_of_ne TopologicalSpace.IsTopologicalBasis.exists_mem_of_ne
protected theorem Finset.isClosed [T1Space X] (s : Finset X) : IsClosed (s : Set X) :=
s.finite_toSet.isClosed
#align finset.is_closed Finset.isClosed
theorem t1Space_TFAE (X : Type u) [TopologicalSpace X] :
List.TFAE [T1Space X,
∀ x, IsClosed ({ x } : Set X),
∀ x, IsOpen ({ x }ᶜ : Set X),
Continuous (@CofiniteTopology.of X),
∀ ⦃x y : X⦄, x ≠ y → {y}ᶜ ∈ 𝓝 x,
∀ ⦃x y : X⦄, x ≠ y → ∃ s ∈ 𝓝 x, y ∉ s,
∀ ⦃x y : X⦄, x ≠ y → ∃ U : Set X, IsOpen U ∧ x ∈ U ∧ y ∉ U,
∀ ⦃x y : X⦄, x ≠ y → Disjoint (𝓝 x) (pure y),
∀ ⦃x y : X⦄, x ≠ y → Disjoint (pure x) (𝓝 y),
∀ ⦃x y : X⦄, x ⤳ y → x = y] := by
tfae_have 1 ↔ 2
· exact ⟨fun h => h.1, fun h => ⟨h⟩⟩
tfae_have 2 ↔ 3
· simp only [isOpen_compl_iff]
tfae_have 5 ↔ 3
· refine forall_swap.trans ?_
simp only [isOpen_iff_mem_nhds, mem_compl_iff, mem_singleton_iff]
tfae_have 5 ↔ 6
· simp only [← subset_compl_singleton_iff, exists_mem_subset_iff]
tfae_have 5 ↔ 7
· simp only [(nhds_basis_opens _).mem_iff, subset_compl_singleton_iff, exists_prop, and_assoc,
and_left_comm]
tfae_have 5 ↔ 8
· simp only [← principal_singleton, disjoint_principal_right]
tfae_have 8 ↔ 9
· exact forall_swap.trans (by simp only [disjoint_comm, ne_comm])
tfae_have 1 → 4
· simp only [continuous_def, CofiniteTopology.isOpen_iff']
rintro H s (rfl | hs)
exacts [isOpen_empty, compl_compl s ▸ (@Set.Finite.isClosed _ _ H _ hs).isOpen_compl]
tfae_have 4 → 2
· exact fun h x => (CofiniteTopology.isClosed_iff.2 <| Or.inr (finite_singleton _)).preimage h
tfae_have 2 ↔ 10
· simp only [← closure_subset_iff_isClosed, specializes_iff_mem_closure, subset_def,
mem_singleton_iff, eq_comm]
tfae_finish
#align t1_space_tfae t1Space_TFAE
theorem t1Space_iff_continuous_cofinite_of : T1Space X ↔ Continuous (@CofiniteTopology.of X) :=
(t1Space_TFAE X).out 0 3
#align t1_space_iff_continuous_cofinite_of t1Space_iff_continuous_cofinite_of
theorem CofiniteTopology.continuous_of [T1Space X] : Continuous (@CofiniteTopology.of X) :=
t1Space_iff_continuous_cofinite_of.mp ‹_›
#align cofinite_topology.continuous_of CofiniteTopology.continuous_of
theorem t1Space_iff_exists_open :
T1Space X ↔ Pairwise fun x y => ∃ U : Set X, IsOpen U ∧ x ∈ U ∧ y ∉ U :=
(t1Space_TFAE X).out 0 6
#align t1_space_iff_exists_open t1Space_iff_exists_open
theorem t1Space_iff_disjoint_pure_nhds : T1Space X ↔ ∀ ⦃x y : X⦄, x ≠ y → Disjoint (pure x) (𝓝 y) :=
(t1Space_TFAE X).out 0 8
#align t1_space_iff_disjoint_pure_nhds t1Space_iff_disjoint_pure_nhds
theorem t1Space_iff_disjoint_nhds_pure : T1Space X ↔ ∀ ⦃x y : X⦄, x ≠ y → Disjoint (𝓝 x) (pure y) :=
(t1Space_TFAE X).out 0 7
#align t1_space_iff_disjoint_nhds_pure t1Space_iff_disjoint_nhds_pure
theorem t1Space_iff_specializes_imp_eq : T1Space X ↔ ∀ ⦃x y : X⦄, x ⤳ y → x = y :=
(t1Space_TFAE X).out 0 9
#align t1_space_iff_specializes_imp_eq t1Space_iff_specializes_imp_eq
theorem disjoint_pure_nhds [T1Space X] {x y : X} (h : x ≠ y) : Disjoint (pure x) (𝓝 y) :=
t1Space_iff_disjoint_pure_nhds.mp ‹_› h
#align disjoint_pure_nhds disjoint_pure_nhds
theorem disjoint_nhds_pure [T1Space X] {x y : X} (h : x ≠ y) : Disjoint (𝓝 x) (pure y) :=
t1Space_iff_disjoint_nhds_pure.mp ‹_› h
#align disjoint_nhds_pure disjoint_nhds_pure
theorem Specializes.eq [T1Space X] {x y : X} (h : x ⤳ y) : x = y :=
t1Space_iff_specializes_imp_eq.1 ‹_› h
#align specializes.eq Specializes.eq
theorem specializes_iff_eq [T1Space X] {x y : X} : x ⤳ y ↔ x = y :=
⟨Specializes.eq, fun h => h ▸ specializes_rfl⟩
#align specializes_iff_eq specializes_iff_eq
@[simp] theorem specializes_eq_eq [T1Space X] : (· ⤳ ·) = @Eq X :=
funext₂ fun _ _ => propext specializes_iff_eq
#align specializes_eq_eq specializes_eq_eq
@[simp]
theorem pure_le_nhds_iff [T1Space X] {a b : X} : pure a ≤ 𝓝 b ↔ a = b :=
specializes_iff_pure.symm.trans specializes_iff_eq
#align pure_le_nhds_iff pure_le_nhds_iff
@[simp]
theorem nhds_le_nhds_iff [T1Space X] {a b : X} : 𝓝 a ≤ 𝓝 b ↔ a = b :=
specializes_iff_eq
#align nhds_le_nhds_iff nhds_le_nhds_iff
instance (priority := 100) [T1Space X] : R0Space X where
specializes_symmetric _ _ := by rw [specializes_iff_eq, specializes_iff_eq]; exact Eq.symm
instance : T1Space (CofiniteTopology X) :=
t1Space_iff_continuous_cofinite_of.mpr continuous_id
theorem t1Space_antitone : Antitone (@T1Space X) := fun a _ h _ =>
@T1Space.mk _ a fun x => (T1Space.t1 x).mono h
#align t1_space_antitone t1Space_antitone
theorem continuousWithinAt_update_of_ne [T1Space X] [DecidableEq X] [TopologicalSpace Y] {f : X → Y}
{s : Set X} {x x' : X} {y : Y} (hne : x' ≠ x) :
ContinuousWithinAt (Function.update f x y) s x' ↔ ContinuousWithinAt f s x' :=
EventuallyEq.congr_continuousWithinAt
(mem_nhdsWithin_of_mem_nhds <| mem_of_superset (isOpen_ne.mem_nhds hne) fun _y' hy' =>
Function.update_noteq hy' _ _)
(Function.update_noteq hne _ _)
#align continuous_within_at_update_of_ne continuousWithinAt_update_of_ne
theorem continuousAt_update_of_ne [T1Space X] [DecidableEq X] [TopologicalSpace Y]
{f : X → Y} {x x' : X} {y : Y} (hne : x' ≠ x) :
ContinuousAt (Function.update f x y) x' ↔ ContinuousAt f x' := by
simp only [← continuousWithinAt_univ, continuousWithinAt_update_of_ne hne]
#align continuous_at_update_of_ne continuousAt_update_of_ne
theorem continuousOn_update_iff [T1Space X] [DecidableEq X] [TopologicalSpace Y] {f : X → Y}
{s : Set X} {x : X} {y : Y} :
ContinuousOn (Function.update f x y) s ↔
ContinuousOn f (s \ {x}) ∧ (x ∈ s → Tendsto f (𝓝[s \ {x}] x) (𝓝 y)) := by
rw [ContinuousOn, ← and_forall_ne x, and_comm]
refine and_congr ⟨fun H z hz => ?_, fun H z hzx hzs => ?_⟩ (forall_congr' fun _ => ?_)
· specialize H z hz.2 hz.1
rw [continuousWithinAt_update_of_ne hz.2] at H
exact H.mono diff_subset
· rw [continuousWithinAt_update_of_ne hzx]
refine (H z ⟨hzs, hzx⟩).mono_of_mem (inter_mem_nhdsWithin _ ?_)
exact isOpen_ne.mem_nhds hzx
· exact continuousWithinAt_update_same
#align continuous_on_update_iff continuousOn_update_iff
theorem t1Space_of_injective_of_continuous [TopologicalSpace Y] {f : X → Y}
(hf : Function.Injective f) (hf' : Continuous f) [T1Space Y] : T1Space X :=
t1Space_iff_specializes_imp_eq.2 fun _ _ h => hf (h.map hf').eq
#align t1_space_of_injective_of_continuous t1Space_of_injective_of_continuous
protected theorem Embedding.t1Space [TopologicalSpace Y] [T1Space Y] {f : X → Y}
(hf : Embedding f) : T1Space X :=
t1Space_of_injective_of_continuous hf.inj hf.continuous
#align embedding.t1_space Embedding.t1Space
instance Subtype.t1Space {X : Type u} [TopologicalSpace X] [T1Space X] {p : X → Prop} :
T1Space (Subtype p) :=
embedding_subtype_val.t1Space
#align subtype.t1_space Subtype.t1Space
instance [TopologicalSpace Y] [T1Space X] [T1Space Y] : T1Space (X × Y) :=
⟨fun ⟨a, b⟩ => @singleton_prod_singleton _ _ a b ▸ isClosed_singleton.prod isClosed_singleton⟩
instance {ι : Type*} {X : ι → Type*} [∀ i, TopologicalSpace (X i)] [∀ i, T1Space (X i)] :
T1Space (∀ i, X i) :=
⟨fun f => univ_pi_singleton f ▸ isClosed_set_pi fun _ _ => isClosed_singleton⟩
instance ULift.instT1Space [T1Space X] : T1Space (ULift X) :=
embedding_uLift_down.t1Space
-- see Note [lower instance priority]
instance (priority := 100) TotallyDisconnectedSpace.t1Space [h: TotallyDisconnectedSpace X] :
T1Space X := by
rw [((t1Space_TFAE X).out 0 1 :)]
intro x
rw [← totallyDisconnectedSpace_iff_connectedComponent_singleton.mp h x]
exact isClosed_connectedComponent
-- see Note [lower instance priority]
instance (priority := 100) T1Space.t0Space [T1Space X] : T0Space X :=
⟨fun _ _ h => h.specializes.eq⟩
#align t1_space.t0_space T1Space.t0Space
@[simp]
theorem compl_singleton_mem_nhds_iff [T1Space X] {x y : X} : {x}ᶜ ∈ 𝓝 y ↔ y ≠ x :=
isOpen_compl_singleton.mem_nhds_iff
#align compl_singleton_mem_nhds_iff compl_singleton_mem_nhds_iff
theorem compl_singleton_mem_nhds [T1Space X] {x y : X} (h : y ≠ x) : {x}ᶜ ∈ 𝓝 y :=
compl_singleton_mem_nhds_iff.mpr h
#align compl_singleton_mem_nhds compl_singleton_mem_nhds
@[simp]
theorem closure_singleton [T1Space X] {x : X} : closure ({x} : Set X) = {x} :=
isClosed_singleton.closure_eq
#align closure_singleton closure_singleton
-- Porting note (#11215): TODO: the proof was `hs.induction_on (by simp) fun x => by simp`
theorem Set.Subsingleton.closure [T1Space X] {s : Set X} (hs : s.Subsingleton) :
(closure s).Subsingleton := by
rcases hs.eq_empty_or_singleton with (rfl | ⟨x, rfl⟩) <;> simp
#align set.subsingleton.closure Set.Subsingleton.closure
@[simp]
theorem subsingleton_closure [T1Space X] {s : Set X} : (closure s).Subsingleton ↔ s.Subsingleton :=
⟨fun h => h.anti subset_closure, fun h => h.closure⟩
#align subsingleton_closure subsingleton_closure
theorem isClosedMap_const {X Y} [TopologicalSpace X] [TopologicalSpace Y] [T1Space Y] {y : Y} :
IsClosedMap (Function.const X y) :=
IsClosedMap.of_nonempty fun s _ h2s => by simp_rw [const, h2s.image_const, isClosed_singleton]
#align is_closed_map_const isClosedMap_const
theorem nhdsWithin_insert_of_ne [T1Space X] {x y : X} {s : Set X} (hxy : x ≠ y) :
𝓝[insert y s] x = 𝓝[s] x := by
refine le_antisymm (Filter.le_def.2 fun t ht => ?_) (nhdsWithin_mono x <| subset_insert y s)
obtain ⟨o, ho, hxo, host⟩ := mem_nhdsWithin.mp ht
refine mem_nhdsWithin.mpr ⟨o \ {y}, ho.sdiff isClosed_singleton, ⟨hxo, hxy⟩, ?_⟩
rw [inter_insert_of_not_mem <| not_mem_diff_of_mem (mem_singleton y)]
exact (inter_subset_inter diff_subset Subset.rfl).trans host
#align nhds_within_insert_of_ne nhdsWithin_insert_of_ne
theorem insert_mem_nhdsWithin_of_subset_insert [T1Space X] {x y : X} {s t : Set X}
(hu : t ⊆ insert y s) : insert x s ∈ 𝓝[t] x := by
rcases eq_or_ne x y with (rfl | h)
· exact mem_of_superset self_mem_nhdsWithin hu
refine nhdsWithin_mono x hu ?_
rw [nhdsWithin_insert_of_ne h]
exact mem_of_superset self_mem_nhdsWithin (subset_insert x s)
#align insert_mem_nhds_within_of_subset_insert insert_mem_nhdsWithin_of_subset_insert
@[simp]
theorem ker_nhds [T1Space X] (x : X) : (𝓝 x).ker = {x} := by
simp [ker_nhds_eq_specializes]
theorem biInter_basis_nhds [T1Space X] {ι : Sort*} {p : ι → Prop} {s : ι → Set X} {x : X}
(h : (𝓝 x).HasBasis p s) : ⋂ (i) (_ : p i), s i = {x} := by
rw [← h.ker, ker_nhds]
#align bInter_basis_nhds biInter_basis_nhds
@[simp]
theorem compl_singleton_mem_nhdsSet_iff [T1Space X] {x : X} {s : Set X} : {x}ᶜ ∈ 𝓝ˢ s ↔ x ∉ s := by
rw [isOpen_compl_singleton.mem_nhdsSet, subset_compl_singleton_iff]
#align compl_singleton_mem_nhds_set_iff compl_singleton_mem_nhdsSet_iff
@[simp]
theorem nhdsSet_le_iff [T1Space X] {s t : Set X} : 𝓝ˢ s ≤ 𝓝ˢ t ↔ s ⊆ t := by
refine ⟨?_, fun h => monotone_nhdsSet h⟩
simp_rw [Filter.le_def]; intro h x hx
specialize h {x}ᶜ
simp_rw [compl_singleton_mem_nhdsSet_iff] at h
by_contra hxt
exact h hxt hx
#align nhds_set_le_iff nhdsSet_le_iff
@[simp]
theorem nhdsSet_inj_iff [T1Space X] {s t : Set X} : 𝓝ˢ s = 𝓝ˢ t ↔ s = t := by
simp_rw [le_antisymm_iff]
exact and_congr nhdsSet_le_iff nhdsSet_le_iff
#align nhds_set_inj_iff nhdsSet_inj_iff
theorem injective_nhdsSet [T1Space X] : Function.Injective (𝓝ˢ : Set X → Filter X) := fun _ _ hst =>
nhdsSet_inj_iff.mp hst
#align injective_nhds_set injective_nhdsSet
theorem strictMono_nhdsSet [T1Space X] : StrictMono (𝓝ˢ : Set X → Filter X) :=
monotone_nhdsSet.strictMono_of_injective injective_nhdsSet
#align strict_mono_nhds_set strictMono_nhdsSet
@[simp]
theorem nhds_le_nhdsSet_iff [T1Space X] {s : Set X} {x : X} : 𝓝 x ≤ 𝓝ˢ s ↔ x ∈ s := by
rw [← nhdsSet_singleton, nhdsSet_le_iff, singleton_subset_iff]
#align nhds_le_nhds_set_iff nhds_le_nhdsSet_iff
theorem Dense.diff_singleton [T1Space X] {s : Set X} (hs : Dense s) (x : X) [NeBot (𝓝[≠] x)] :
Dense (s \ {x}) :=
hs.inter_of_isOpen_right (dense_compl_singleton x) isOpen_compl_singleton
#align dense.diff_singleton Dense.diff_singleton
theorem Dense.diff_finset [T1Space X] [∀ x : X, NeBot (𝓝[≠] x)] {s : Set X} (hs : Dense s)
(t : Finset X) : Dense (s \ t) := by
induction t using Finset.induction_on with
| empty => simpa using hs
| insert _ ih =>
rw [Finset.coe_insert, ← union_singleton, ← diff_diff]
exact ih.diff_singleton _
#align dense.diff_finset Dense.diff_finset
theorem Dense.diff_finite [T1Space X] [∀ x : X, NeBot (𝓝[≠] x)] {s : Set X} (hs : Dense s)
{t : Set X} (ht : t.Finite) : Dense (s \ t) := by
convert hs.diff_finset ht.toFinset
exact (Finite.coe_toFinset _).symm
#align dense.diff_finite Dense.diff_finite
theorem eq_of_tendsto_nhds [TopologicalSpace Y] [T1Space Y] {f : X → Y} {x : X} {y : Y}
(h : Tendsto f (𝓝 x) (𝓝 y)) : f x = y :=
by_contra fun hfa : f x ≠ y =>
have fact₁ : {f x}ᶜ ∈ 𝓝 y := compl_singleton_mem_nhds hfa.symm
have fact₂ : Tendsto f (pure x) (𝓝 y) := h.comp (tendsto_id'.2 <| pure_le_nhds x)
fact₂ fact₁ (Eq.refl <| f x)
#align eq_of_tendsto_nhds eq_of_tendsto_nhds
theorem Filter.Tendsto.eventually_ne [TopologicalSpace Y] [T1Space Y] {g : X → Y}
{l : Filter X} {b₁ b₂ : Y} (hg : Tendsto g l (𝓝 b₁)) (hb : b₁ ≠ b₂) : ∀ᶠ z in l, g z ≠ b₂ :=
hg.eventually (isOpen_compl_singleton.eventually_mem hb)
#align filter.tendsto.eventually_ne Filter.Tendsto.eventually_ne
theorem ContinuousAt.eventually_ne [TopologicalSpace Y] [T1Space Y] {g : X → Y} {x : X} {y : Y}
(hg1 : ContinuousAt g x) (hg2 : g x ≠ y) : ∀ᶠ z in 𝓝 x, g z ≠ y :=
hg1.tendsto.eventually_ne hg2
#align continuous_at.eventually_ne ContinuousAt.eventually_ne
theorem eventually_ne_nhds [T1Space X] {a b : X} (h : a ≠ b) : ∀ᶠ x in 𝓝 a, x ≠ b :=
IsOpen.eventually_mem isOpen_ne h
theorem eventually_ne_nhdsWithin [T1Space X] {a b : X} {s : Set X} (h : a ≠ b) :
∀ᶠ x in 𝓝[s] a, x ≠ b :=
Filter.Eventually.filter_mono nhdsWithin_le_nhds <| eventually_ne_nhds h
theorem continuousAt_of_tendsto_nhds [TopologicalSpace Y] [T1Space Y] {f : X → Y} {x : X} {y : Y}
(h : Tendsto f (𝓝 x) (𝓝 y)) : ContinuousAt f x := by
rwa [ContinuousAt, eq_of_tendsto_nhds h]
#align continuous_at_of_tendsto_nhds continuousAt_of_tendsto_nhds
@[simp]
theorem tendsto_const_nhds_iff [T1Space X] {l : Filter Y} [NeBot l] {c d : X} :
Tendsto (fun _ => c) l (𝓝 d) ↔ c = d := by simp_rw [Tendsto, Filter.map_const, pure_le_nhds_iff]
#align tendsto_const_nhds_iff tendsto_const_nhds_iff
theorem isOpen_singleton_of_finite_mem_nhds [T1Space X] (x : X)
{s : Set X} (hs : s ∈ 𝓝 x) (hsf : s.Finite) : IsOpen ({x} : Set X) := by
have A : {x} ⊆ s := by simp only [singleton_subset_iff, mem_of_mem_nhds hs]
have B : IsClosed (s \ {x}) := (hsf.subset diff_subset).isClosed
have C : (s \ {x})ᶜ ∈ 𝓝 x := B.isOpen_compl.mem_nhds fun h => h.2 rfl
have D : {x} ∈ 𝓝 x := by simpa only [← diff_eq, diff_diff_cancel_left A] using inter_mem hs C
rwa [← mem_interior_iff_mem_nhds, ← singleton_subset_iff, subset_interior_iff_isOpen] at D
#align is_open_singleton_of_finite_mem_nhds isOpen_singleton_of_finite_mem_nhds
theorem infinite_of_mem_nhds {X} [TopologicalSpace X] [T1Space X] (x : X) [hx : NeBot (𝓝[≠] x)]
{s : Set X} (hs : s ∈ 𝓝 x) : Set.Infinite s := by
refine fun hsf => hx.1 ?_
rw [← isOpen_singleton_iff_punctured_nhds]
exact isOpen_singleton_of_finite_mem_nhds x hs hsf
#align infinite_of_mem_nhds infinite_of_mem_nhds
theorem discrete_of_t1_of_finite [T1Space X] [Finite X] :
DiscreteTopology X := by
apply singletons_open_iff_discrete.mp
intro x
rw [← isClosed_compl_iff]
exact (Set.toFinite _).isClosed
#align discrete_of_t1_of_finite discrete_of_t1_of_finite
theorem PreconnectedSpace.trivial_of_discrete [PreconnectedSpace X] [DiscreteTopology X] :
Subsingleton X := by
rw [← not_nontrivial_iff_subsingleton]
rintro ⟨x, y, hxy⟩
rw [Ne, ← mem_singleton_iff, (isClopen_discrete _).eq_univ <| singleton_nonempty y] at hxy
exact hxy (mem_univ x)
#align preconnected_space.trivial_of_discrete PreconnectedSpace.trivial_of_discrete
theorem IsPreconnected.infinite_of_nontrivial [T1Space X] {s : Set X} (h : IsPreconnected s)
(hs : s.Nontrivial) : s.Infinite := by
refine mt (fun hf => (subsingleton_coe s).mp ?_) (not_subsingleton_iff.mpr hs)
haveI := @discrete_of_t1_of_finite s _ _ hf.to_subtype
exact @PreconnectedSpace.trivial_of_discrete _ _ (Subtype.preconnectedSpace h) _
#align is_preconnected.infinite_of_nontrivial IsPreconnected.infinite_of_nontrivial
theorem ConnectedSpace.infinite [ConnectedSpace X] [Nontrivial X] [T1Space X] : Infinite X :=
infinite_univ_iff.mp <| isPreconnected_univ.infinite_of_nontrivial nontrivial_univ
#align connected_space.infinite ConnectedSpace.infinite
instance (priority := 100) ConnectedSpace.neBot_nhdsWithin_compl_of_nontrivial_of_t1space
[ConnectedSpace X] [Nontrivial X] [T1Space X] (x : X) :
NeBot (𝓝[≠] x) := by
by_contra contra
rw [not_neBot, ← isOpen_singleton_iff_punctured_nhds] at contra
replace contra := nonempty_inter isOpen_compl_singleton
contra (compl_union_self _) (Set.nonempty_compl_of_nontrivial _) (singleton_nonempty _)
simp [compl_inter_self {x}] at contra
| Mathlib/Topology/Separation.lean | 930 | 939 | theorem SeparationQuotient.t1Space_iff : T1Space (SeparationQuotient X) ↔ R0Space X := by |
rw [r0Space_iff, ((t1Space_TFAE (SeparationQuotient X)).out 0 9 :)]
constructor
· intro h x y xspecy
rw [← Inducing.specializes_iff inducing_mk, h xspecy] at *
· rintro h ⟨x⟩ ⟨y⟩ sxspecsy
have xspecy : x ⤳ y := (Inducing.specializes_iff inducing_mk).mp sxspecsy
have yspecx : y ⤳ x := h xspecy
erw [mk_eq_mk, inseparable_iff_specializes_and]
exact ⟨xspecy, yspecx⟩
|
import Mathlib.Topology.Separation
#align_import topology.extend_from from "leanprover-community/mathlib"@"b363547b3113d350d053abdf2884e9850a56b205"
noncomputable section
open Topology
open Filter Set
variable {X Y : Type*} [TopologicalSpace X] [TopologicalSpace Y]
def extendFrom (A : Set X) (f : X → Y) : X → Y :=
fun x ↦ @limUnder _ _ _ ⟨f x⟩ (𝓝[A] x) f
#align extend_from extendFrom
theorem tendsto_extendFrom {A : Set X} {f : X → Y} {x : X} (h : ∃ y, Tendsto f (𝓝[A] x) (𝓝 y)) :
Tendsto f (𝓝[A] x) (𝓝 <| extendFrom A f x) :=
tendsto_nhds_limUnder h
#align tendsto_extend_from tendsto_extendFrom
theorem extendFrom_eq [T2Space Y] {A : Set X} {f : X → Y} {x : X} {y : Y} (hx : x ∈ closure A)
(hf : Tendsto f (𝓝[A] x) (𝓝 y)) : extendFrom A f x = y :=
haveI := mem_closure_iff_nhdsWithin_neBot.mp hx
tendsto_nhds_unique (tendsto_nhds_limUnder ⟨y, hf⟩) hf
#align extend_from_eq extendFrom_eq
theorem extendFrom_extends [T2Space Y] {f : X → Y} {A : Set X} (hf : ContinuousOn f A) :
∀ x ∈ A, extendFrom A f x = f x :=
fun x x_in ↦ extendFrom_eq (subset_closure x_in) (hf x x_in)
#align extend_from_extends extendFrom_extends
theorem continuousOn_extendFrom [RegularSpace Y] {f : X → Y} {A B : Set X} (hB : B ⊆ closure A)
(hf : ∀ x ∈ B, ∃ y, Tendsto f (𝓝[A] x) (𝓝 y)) : ContinuousOn (extendFrom A f) B := by
set φ := extendFrom A f
intro x x_in
suffices ∀ V' ∈ 𝓝 (φ x), IsClosed V' → φ ⁻¹' V' ∈ 𝓝[B] x by
simpa [ContinuousWithinAt, (closed_nhds_basis (φ x)).tendsto_right_iff]
intro V' V'_in V'_closed
obtain ⟨V, V_in, V_op, hV⟩ : ∃ V ∈ 𝓝 x, IsOpen V ∧ V ∩ A ⊆ f ⁻¹' V' := by
have := tendsto_extendFrom (hf x x_in)
rcases (nhdsWithin_basis_open x A).tendsto_left_iff.mp this V' V'_in with ⟨V, ⟨hxV, V_op⟩, hV⟩
exact ⟨V, IsOpen.mem_nhds V_op hxV, V_op, hV⟩
suffices ∀ y ∈ V ∩ B, φ y ∈ V' from
mem_of_superset (inter_mem_inf V_in <| mem_principal_self B) this
rintro y ⟨hyV, hyB⟩
haveI := mem_closure_iff_nhdsWithin_neBot.mp (hB hyB)
have limy : Tendsto f (𝓝[A] y) (𝓝 <| φ y) := tendsto_extendFrom (hf y hyB)
have hVy : V ∈ 𝓝 y := IsOpen.mem_nhds V_op hyV
have : V ∩ A ∈ 𝓝[A] y := by simpa only [inter_comm] using inter_mem_nhdsWithin A hVy
exact V'_closed.mem_of_tendsto limy (mem_of_superset this hV)
#align continuous_on_extend_from continuousOn_extendFrom
| Mathlib/Topology/ExtendFrom.lean | 86 | 89 | theorem continuous_extendFrom [RegularSpace Y] {f : X → Y} {A : Set X} (hA : Dense A)
(hf : ∀ x, ∃ y, Tendsto f (𝓝[A] x) (𝓝 y)) : Continuous (extendFrom A f) := by |
rw [continuous_iff_continuousOn_univ]
exact continuousOn_extendFrom (fun x _ ↦ hA x) (by simpa using hf)
|
import Mathlib.MeasureTheory.Integral.IntegrableOn
import Mathlib.MeasureTheory.Integral.Bochner
import Mathlib.MeasureTheory.Function.LocallyIntegrable
import Mathlib.Topology.MetricSpace.ThickenedIndicator
import Mathlib.Topology.ContinuousFunction.Compact
import Mathlib.Analysis.NormedSpace.HahnBanach.SeparatingDual
#align_import measure_theory.integral.setIntegral from "leanprover-community/mathlib"@"24e0c85412ff6adbeca08022c25ba4876eedf37a"
assert_not_exists InnerProductSpace
noncomputable section
open Set Filter TopologicalSpace MeasureTheory Function RCLike
open scoped Classical Topology ENNReal NNReal
variable {X Y E F : Type*} [MeasurableSpace X]
namespace MeasureTheory
section NormedAddCommGroup
variable [NormedAddCommGroup E] [NormedSpace ℝ E]
{f g : X → E} {s t : Set X} {μ ν : Measure X} {l l' : Filter X}
theorem setIntegral_congr_ae₀ (hs : NullMeasurableSet s μ) (h : ∀ᵐ x ∂μ, x ∈ s → f x = g x) :
∫ x in s, f x ∂μ = ∫ x in s, g x ∂μ :=
integral_congr_ae ((ae_restrict_iff'₀ hs).2 h)
#align measure_theory.set_integral_congr_ae₀ MeasureTheory.setIntegral_congr_ae₀
@[deprecated (since := "2024-04-17")]
alias set_integral_congr_ae₀ := setIntegral_congr_ae₀
theorem setIntegral_congr_ae (hs : MeasurableSet s) (h : ∀ᵐ x ∂μ, x ∈ s → f x = g x) :
∫ x in s, f x ∂μ = ∫ x in s, g x ∂μ :=
integral_congr_ae ((ae_restrict_iff' hs).2 h)
#align measure_theory.set_integral_congr_ae MeasureTheory.setIntegral_congr_ae
@[deprecated (since := "2024-04-17")]
alias set_integral_congr_ae := setIntegral_congr_ae
theorem setIntegral_congr₀ (hs : NullMeasurableSet s μ) (h : EqOn f g s) :
∫ x in s, f x ∂μ = ∫ x in s, g x ∂μ :=
setIntegral_congr_ae₀ hs <| eventually_of_forall h
#align measure_theory.set_integral_congr₀ MeasureTheory.setIntegral_congr₀
@[deprecated (since := "2024-04-17")]
alias set_integral_congr₀ := setIntegral_congr₀
theorem setIntegral_congr (hs : MeasurableSet s) (h : EqOn f g s) :
∫ x in s, f x ∂μ = ∫ x in s, g x ∂μ :=
setIntegral_congr_ae hs <| eventually_of_forall h
#align measure_theory.set_integral_congr MeasureTheory.setIntegral_congr
@[deprecated (since := "2024-04-17")]
alias set_integral_congr := setIntegral_congr
theorem setIntegral_congr_set_ae (hst : s =ᵐ[μ] t) : ∫ x in s, f x ∂μ = ∫ x in t, f x ∂μ := by
rw [Measure.restrict_congr_set hst]
#align measure_theory.set_integral_congr_set_ae MeasureTheory.setIntegral_congr_set_ae
@[deprecated (since := "2024-04-17")]
alias set_integral_congr_set_ae := setIntegral_congr_set_ae
theorem integral_union_ae (hst : AEDisjoint μ s t) (ht : NullMeasurableSet t μ)
(hfs : IntegrableOn f s μ) (hft : IntegrableOn f t μ) :
∫ x in s ∪ t, f x ∂μ = ∫ x in s, f x ∂μ + ∫ x in t, f x ∂μ := by
simp only [IntegrableOn, Measure.restrict_union₀ hst ht, integral_add_measure hfs hft]
#align measure_theory.integral_union_ae MeasureTheory.integral_union_ae
theorem integral_union (hst : Disjoint s t) (ht : MeasurableSet t) (hfs : IntegrableOn f s μ)
(hft : IntegrableOn f t μ) : ∫ x in s ∪ t, f x ∂μ = ∫ x in s, f x ∂μ + ∫ x in t, f x ∂μ :=
integral_union_ae hst.aedisjoint ht.nullMeasurableSet hfs hft
#align measure_theory.integral_union MeasureTheory.integral_union
theorem integral_diff (ht : MeasurableSet t) (hfs : IntegrableOn f s μ) (hts : t ⊆ s) :
∫ x in s \ t, f x ∂μ = ∫ x in s, f x ∂μ - ∫ x in t, f x ∂μ := by
rw [eq_sub_iff_add_eq, ← integral_union, diff_union_of_subset hts]
exacts [disjoint_sdiff_self_left, ht, hfs.mono_set diff_subset, hfs.mono_set hts]
#align measure_theory.integral_diff MeasureTheory.integral_diff
theorem integral_inter_add_diff₀ (ht : NullMeasurableSet t μ) (hfs : IntegrableOn f s μ) :
∫ x in s ∩ t, f x ∂μ + ∫ x in s \ t, f x ∂μ = ∫ x in s, f x ∂μ := by
rw [← Measure.restrict_inter_add_diff₀ s ht, integral_add_measure]
· exact Integrable.mono_measure hfs (Measure.restrict_mono inter_subset_left le_rfl)
· exact Integrable.mono_measure hfs (Measure.restrict_mono diff_subset le_rfl)
#align measure_theory.integral_inter_add_diff₀ MeasureTheory.integral_inter_add_diff₀
theorem integral_inter_add_diff (ht : MeasurableSet t) (hfs : IntegrableOn f s μ) :
∫ x in s ∩ t, f x ∂μ + ∫ x in s \ t, f x ∂μ = ∫ x in s, f x ∂μ :=
integral_inter_add_diff₀ ht.nullMeasurableSet hfs
#align measure_theory.integral_inter_add_diff MeasureTheory.integral_inter_add_diff
theorem integral_finset_biUnion {ι : Type*} (t : Finset ι) {s : ι → Set X}
(hs : ∀ i ∈ t, MeasurableSet (s i)) (h's : Set.Pairwise (↑t) (Disjoint on s))
(hf : ∀ i ∈ t, IntegrableOn f (s i) μ) :
∫ x in ⋃ i ∈ t, s i, f x ∂μ = ∑ i ∈ t, ∫ x in s i, f x ∂μ := by
induction' t using Finset.induction_on with a t hat IH hs h's
· simp
· simp only [Finset.coe_insert, Finset.forall_mem_insert, Set.pairwise_insert,
Finset.set_biUnion_insert] at hs hf h's ⊢
rw [integral_union _ _ hf.1 (integrableOn_finset_iUnion.2 hf.2)]
· rw [Finset.sum_insert hat, IH hs.2 h's.1 hf.2]
· simp only [disjoint_iUnion_right]
exact fun i hi => (h's.2 i hi (ne_of_mem_of_not_mem hi hat).symm).1
· exact Finset.measurableSet_biUnion _ hs.2
#align measure_theory.integral_finset_bUnion MeasureTheory.integral_finset_biUnion
theorem integral_fintype_iUnion {ι : Type*} [Fintype ι] {s : ι → Set X}
(hs : ∀ i, MeasurableSet (s i)) (h's : Pairwise (Disjoint on s))
(hf : ∀ i, IntegrableOn f (s i) μ) : ∫ x in ⋃ i, s i, f x ∂μ = ∑ i, ∫ x in s i, f x ∂μ := by
convert integral_finset_biUnion Finset.univ (fun i _ => hs i) _ fun i _ => hf i
· simp
· simp [pairwise_univ, h's]
#align measure_theory.integral_fintype_Union MeasureTheory.integral_fintype_iUnion
theorem integral_empty : ∫ x in ∅, f x ∂μ = 0 := by
rw [Measure.restrict_empty, integral_zero_measure]
#align measure_theory.integral_empty MeasureTheory.integral_empty
theorem integral_univ : ∫ x in univ, f x ∂μ = ∫ x, f x ∂μ := by rw [Measure.restrict_univ]
#align measure_theory.integral_univ MeasureTheory.integral_univ
theorem integral_add_compl₀ (hs : NullMeasurableSet s μ) (hfi : Integrable f μ) :
∫ x in s, f x ∂μ + ∫ x in sᶜ, f x ∂μ = ∫ x, f x ∂μ := by
rw [
← integral_union_ae disjoint_compl_right.aedisjoint hs.compl hfi.integrableOn hfi.integrableOn,
union_compl_self, integral_univ]
#align measure_theory.integral_add_compl₀ MeasureTheory.integral_add_compl₀
theorem integral_add_compl (hs : MeasurableSet s) (hfi : Integrable f μ) :
∫ x in s, f x ∂μ + ∫ x in sᶜ, f x ∂μ = ∫ x, f x ∂μ :=
integral_add_compl₀ hs.nullMeasurableSet hfi
#align measure_theory.integral_add_compl MeasureTheory.integral_add_compl
theorem integral_indicator (hs : MeasurableSet s) :
∫ x, indicator s f x ∂μ = ∫ x in s, f x ∂μ := by
by_cases hfi : IntegrableOn f s μ; swap
· rw [integral_undef hfi, integral_undef]
rwa [integrable_indicator_iff hs]
calc
∫ x, indicator s f x ∂μ = ∫ x in s, indicator s f x ∂μ + ∫ x in sᶜ, indicator s f x ∂μ :=
(integral_add_compl hs (hfi.integrable_indicator hs)).symm
_ = ∫ x in s, f x ∂μ + ∫ x in sᶜ, 0 ∂μ :=
(congr_arg₂ (· + ·) (integral_congr_ae (indicator_ae_eq_restrict hs))
(integral_congr_ae (indicator_ae_eq_restrict_compl hs)))
_ = ∫ x in s, f x ∂μ := by simp
#align measure_theory.integral_indicator MeasureTheory.integral_indicator
theorem setIntegral_indicator (ht : MeasurableSet t) :
∫ x in s, t.indicator f x ∂μ = ∫ x in s ∩ t, f x ∂μ := by
rw [integral_indicator ht, Measure.restrict_restrict ht, Set.inter_comm]
#align measure_theory.set_integral_indicator MeasureTheory.setIntegral_indicator
@[deprecated (since := "2024-04-17")]
alias set_integral_indicator := setIntegral_indicator
theorem ofReal_setIntegral_one_of_measure_ne_top {X : Type*} {m : MeasurableSpace X}
{μ : Measure X} {s : Set X} (hs : μ s ≠ ∞) : ENNReal.ofReal (∫ _ in s, (1 : ℝ) ∂μ) = μ s :=
calc
ENNReal.ofReal (∫ _ in s, (1 : ℝ) ∂μ) = ENNReal.ofReal (∫ _ in s, ‖(1 : ℝ)‖ ∂μ) := by
simp only [norm_one]
_ = ∫⁻ _ in s, 1 ∂μ := by
rw [ofReal_integral_norm_eq_lintegral_nnnorm (integrableOn_const.2 (Or.inr hs.lt_top))]
simp only [nnnorm_one, ENNReal.coe_one]
_ = μ s := set_lintegral_one _
#align measure_theory.of_real_set_integral_one_of_measure_ne_top MeasureTheory.ofReal_setIntegral_one_of_measure_ne_top
@[deprecated (since := "2024-04-17")]
alias ofReal_set_integral_one_of_measure_ne_top := ofReal_setIntegral_one_of_measure_ne_top
theorem ofReal_setIntegral_one {X : Type*} {_ : MeasurableSpace X} (μ : Measure X)
[IsFiniteMeasure μ] (s : Set X) : ENNReal.ofReal (∫ _ in s, (1 : ℝ) ∂μ) = μ s :=
ofReal_setIntegral_one_of_measure_ne_top (measure_ne_top μ s)
#align measure_theory.of_real_set_integral_one MeasureTheory.ofReal_setIntegral_one
@[deprecated (since := "2024-04-17")]
alias ofReal_set_integral_one := ofReal_setIntegral_one
theorem integral_piecewise [DecidablePred (· ∈ s)] (hs : MeasurableSet s) (hf : IntegrableOn f s μ)
(hg : IntegrableOn g sᶜ μ) :
∫ x, s.piecewise f g x ∂μ = ∫ x in s, f x ∂μ + ∫ x in sᶜ, g x ∂μ := by
rw [← Set.indicator_add_compl_eq_piecewise,
integral_add' (hf.integrable_indicator hs) (hg.integrable_indicator hs.compl),
integral_indicator hs, integral_indicator hs.compl]
#align measure_theory.integral_piecewise MeasureTheory.integral_piecewise
theorem tendsto_setIntegral_of_monotone {ι : Type*} [Countable ι] [SemilatticeSup ι]
{s : ι → Set X} (hsm : ∀ i, MeasurableSet (s i)) (h_mono : Monotone s)
(hfi : IntegrableOn f (⋃ n, s n) μ) :
Tendsto (fun i => ∫ x in s i, f x ∂μ) atTop (𝓝 (∫ x in ⋃ n, s n, f x ∂μ)) := by
have hfi' : ∫⁻ x in ⋃ n, s n, ‖f x‖₊ ∂μ < ∞ := hfi.2
set S := ⋃ i, s i
have hSm : MeasurableSet S := MeasurableSet.iUnion hsm
have hsub : ∀ {i}, s i ⊆ S := @(subset_iUnion s)
rw [← withDensity_apply _ hSm] at hfi'
set ν := μ.withDensity fun x => ‖f x‖₊ with hν
refine Metric.nhds_basis_closedBall.tendsto_right_iff.2 fun ε ε0 => ?_
lift ε to ℝ≥0 using ε0.le
have : ∀ᶠ i in atTop, ν (s i) ∈ Icc (ν S - ε) (ν S + ε) :=
tendsto_measure_iUnion h_mono (ENNReal.Icc_mem_nhds hfi'.ne (ENNReal.coe_pos.2 ε0).ne')
filter_upwards [this] with i hi
rw [mem_closedBall_iff_norm', ← integral_diff (hsm i) hfi hsub, ← coe_nnnorm, NNReal.coe_le_coe, ←
ENNReal.coe_le_coe]
refine (ennnorm_integral_le_lintegral_ennnorm _).trans ?_
rw [← withDensity_apply _ (hSm.diff (hsm _)), ← hν, measure_diff hsub (hsm _)]
exacts [tsub_le_iff_tsub_le.mp hi.1,
(hi.2.trans_lt <| ENNReal.add_lt_top.2 ⟨hfi', ENNReal.coe_lt_top⟩).ne]
#align measure_theory.tendsto_set_integral_of_monotone MeasureTheory.tendsto_setIntegral_of_monotone
@[deprecated (since := "2024-04-17")]
alias tendsto_set_integral_of_monotone := tendsto_setIntegral_of_monotone
theorem tendsto_setIntegral_of_antitone {ι : Type*} [Countable ι] [SemilatticeSup ι]
{s : ι → Set X} (hsm : ∀ i, MeasurableSet (s i)) (h_anti : Antitone s)
(hfi : ∃ i, IntegrableOn f (s i) μ) :
Tendsto (fun i ↦ ∫ x in s i, f x ∂μ) atTop (𝓝 (∫ x in ⋂ n, s n, f x ∂μ)) := by
set S := ⋂ i, s i
have hSm : MeasurableSet S := MeasurableSet.iInter hsm
have hsub i : S ⊆ s i := iInter_subset _ _
set ν := μ.withDensity fun x => ‖f x‖₊ with hν
refine Metric.nhds_basis_closedBall.tendsto_right_iff.2 fun ε ε0 => ?_
lift ε to ℝ≥0 using ε0.le
rcases hfi with ⟨i₀, hi₀⟩
have νi₀ : ν (s i₀) ≠ ∞ := by
simpa [hsm i₀, ν, ENNReal.ofReal, norm_toNNReal] using hi₀.norm.lintegral_lt_top.ne
have νS : ν S ≠ ∞ := ((measure_mono (hsub i₀)).trans_lt νi₀.lt_top).ne
have : ∀ᶠ i in atTop, ν (s i) ∈ Icc (ν S - ε) (ν S + ε) := by
apply tendsto_measure_iInter hsm h_anti ⟨i₀, νi₀⟩
apply ENNReal.Icc_mem_nhds νS (ENNReal.coe_pos.2 ε0).ne'
filter_upwards [this, Ici_mem_atTop i₀] with i hi h'i
rw [mem_closedBall_iff_norm, ← integral_diff hSm (hi₀.mono_set (h_anti h'i)) (hsub i),
← coe_nnnorm, NNReal.coe_le_coe, ← ENNReal.coe_le_coe]
refine (ennnorm_integral_le_lintegral_ennnorm _).trans ?_
rw [← withDensity_apply _ ((hsm _).diff hSm), ← hν, measure_diff (hsub i) hSm νS]
exact tsub_le_iff_left.2 hi.2
@[deprecated (since := "2024-04-17")]
alias tendsto_set_integral_of_antitone := tendsto_setIntegral_of_antitone
theorem hasSum_integral_iUnion_ae {ι : Type*} [Countable ι] {s : ι → Set X}
(hm : ∀ i, NullMeasurableSet (s i) μ) (hd : Pairwise (AEDisjoint μ on s))
(hfi : IntegrableOn f (⋃ i, s i) μ) :
HasSum (fun n => ∫ x in s n, f x ∂μ) (∫ x in ⋃ n, s n, f x ∂μ) := by
simp only [IntegrableOn, Measure.restrict_iUnion_ae hd hm] at hfi ⊢
exact hasSum_integral_measure hfi
#align measure_theory.has_sum_integral_Union_ae MeasureTheory.hasSum_integral_iUnion_ae
theorem hasSum_integral_iUnion {ι : Type*} [Countable ι] {s : ι → Set X}
(hm : ∀ i, MeasurableSet (s i)) (hd : Pairwise (Disjoint on s))
(hfi : IntegrableOn f (⋃ i, s i) μ) :
HasSum (fun n => ∫ x in s n, f x ∂μ) (∫ x in ⋃ n, s n, f x ∂μ) :=
hasSum_integral_iUnion_ae (fun i => (hm i).nullMeasurableSet) (hd.mono fun _ _ h => h.aedisjoint)
hfi
#align measure_theory.has_sum_integral_Union MeasureTheory.hasSum_integral_iUnion
theorem integral_iUnion {ι : Type*} [Countable ι] {s : ι → Set X} (hm : ∀ i, MeasurableSet (s i))
(hd : Pairwise (Disjoint on s)) (hfi : IntegrableOn f (⋃ i, s i) μ) :
∫ x in ⋃ n, s n, f x ∂μ = ∑' n, ∫ x in s n, f x ∂μ :=
(HasSum.tsum_eq (hasSum_integral_iUnion hm hd hfi)).symm
#align measure_theory.integral_Union MeasureTheory.integral_iUnion
theorem integral_iUnion_ae {ι : Type*} [Countable ι] {s : ι → Set X}
(hm : ∀ i, NullMeasurableSet (s i) μ) (hd : Pairwise (AEDisjoint μ on s))
(hfi : IntegrableOn f (⋃ i, s i) μ) : ∫ x in ⋃ n, s n, f x ∂μ = ∑' n, ∫ x in s n, f x ∂μ :=
(HasSum.tsum_eq (hasSum_integral_iUnion_ae hm hd hfi)).symm
#align measure_theory.integral_Union_ae MeasureTheory.integral_iUnion_ae
theorem setIntegral_eq_zero_of_ae_eq_zero (ht_eq : ∀ᵐ x ∂μ, x ∈ t → f x = 0) :
∫ x in t, f x ∂μ = 0 := by
by_cases hf : AEStronglyMeasurable f (μ.restrict t); swap
· rw [integral_undef]
contrapose! hf
exact hf.1
have : ∫ x in t, hf.mk f x ∂μ = 0 := by
refine integral_eq_zero_of_ae ?_
rw [EventuallyEq,
ae_restrict_iff (hf.stronglyMeasurable_mk.measurableSet_eq_fun stronglyMeasurable_zero)]
filter_upwards [ae_imp_of_ae_restrict hf.ae_eq_mk, ht_eq] with x hx h'x h''x
rw [← hx h''x]
exact h'x h''x
rw [← this]
exact integral_congr_ae hf.ae_eq_mk
#align measure_theory.set_integral_eq_zero_of_ae_eq_zero MeasureTheory.setIntegral_eq_zero_of_ae_eq_zero
@[deprecated (since := "2024-04-17")]
alias set_integral_eq_zero_of_ae_eq_zero := setIntegral_eq_zero_of_ae_eq_zero
theorem setIntegral_eq_zero_of_forall_eq_zero (ht_eq : ∀ x ∈ t, f x = 0) :
∫ x in t, f x ∂μ = 0 :=
setIntegral_eq_zero_of_ae_eq_zero (eventually_of_forall ht_eq)
#align measure_theory.set_integral_eq_zero_of_forall_eq_zero MeasureTheory.setIntegral_eq_zero_of_forall_eq_zero
@[deprecated (since := "2024-04-17")]
alias set_integral_eq_zero_of_forall_eq_zero := setIntegral_eq_zero_of_forall_eq_zero
theorem integral_union_eq_left_of_ae_aux (ht_eq : ∀ᵐ x ∂μ.restrict t, f x = 0)
(haux : StronglyMeasurable f) (H : IntegrableOn f (s ∪ t) μ) :
∫ x in s ∪ t, f x ∂μ = ∫ x in s, f x ∂μ := by
let k := f ⁻¹' {0}
have hk : MeasurableSet k := by borelize E; exact haux.measurable (measurableSet_singleton _)
have h's : IntegrableOn f s μ := H.mono subset_union_left le_rfl
have A : ∀ u : Set X, ∫ x in u ∩ k, f x ∂μ = 0 := fun u =>
setIntegral_eq_zero_of_forall_eq_zero fun x hx => hx.2
rw [← integral_inter_add_diff hk h's, ← integral_inter_add_diff hk H, A, A, zero_add, zero_add,
union_diff_distrib, union_comm]
apply setIntegral_congr_set_ae
rw [union_ae_eq_right]
apply measure_mono_null diff_subset
rw [measure_zero_iff_ae_nmem]
filter_upwards [ae_imp_of_ae_restrict ht_eq] with x hx h'x using h'x.2 (hx h'x.1)
#align measure_theory.integral_union_eq_left_of_ae_aux MeasureTheory.integral_union_eq_left_of_ae_aux
theorem integral_union_eq_left_of_ae (ht_eq : ∀ᵐ x ∂μ.restrict t, f x = 0) :
∫ x in s ∪ t, f x ∂μ = ∫ x in s, f x ∂μ := by
have ht : IntegrableOn f t μ := by apply integrableOn_zero.congr_fun_ae; symm; exact ht_eq
by_cases H : IntegrableOn f (s ∪ t) μ; swap
· rw [integral_undef H, integral_undef]; simpa [integrableOn_union, ht] using H
let f' := H.1.mk f
calc
∫ x : X in s ∪ t, f x ∂μ = ∫ x : X in s ∪ t, f' x ∂μ := integral_congr_ae H.1.ae_eq_mk
_ = ∫ x in s, f' x ∂μ := by
apply
integral_union_eq_left_of_ae_aux _ H.1.stronglyMeasurable_mk (H.congr_fun_ae H.1.ae_eq_mk)
filter_upwards [ht_eq,
ae_mono (Measure.restrict_mono subset_union_right le_rfl) H.1.ae_eq_mk] with x hx h'x
rw [← h'x, hx]
_ = ∫ x in s, f x ∂μ :=
integral_congr_ae
(ae_mono (Measure.restrict_mono subset_union_left le_rfl) H.1.ae_eq_mk.symm)
#align measure_theory.integral_union_eq_left_of_ae MeasureTheory.integral_union_eq_left_of_ae
theorem integral_union_eq_left_of_forall₀ {f : X → E} (ht : NullMeasurableSet t μ)
(ht_eq : ∀ x ∈ t, f x = 0) : ∫ x in s ∪ t, f x ∂μ = ∫ x in s, f x ∂μ :=
integral_union_eq_left_of_ae ((ae_restrict_iff'₀ ht).2 (eventually_of_forall ht_eq))
#align measure_theory.integral_union_eq_left_of_forall₀ MeasureTheory.integral_union_eq_left_of_forall₀
theorem integral_union_eq_left_of_forall {f : X → E} (ht : MeasurableSet t)
(ht_eq : ∀ x ∈ t, f x = 0) : ∫ x in s ∪ t, f x ∂μ = ∫ x in s, f x ∂μ :=
integral_union_eq_left_of_forall₀ ht.nullMeasurableSet ht_eq
#align measure_theory.integral_union_eq_left_of_forall MeasureTheory.integral_union_eq_left_of_forall
theorem setIntegral_eq_of_subset_of_ae_diff_eq_zero_aux (hts : s ⊆ t)
(h't : ∀ᵐ x ∂μ, x ∈ t \ s → f x = 0) (haux : StronglyMeasurable f)
(h'aux : IntegrableOn f t μ) : ∫ x in t, f x ∂μ = ∫ x in s, f x ∂μ := by
let k := f ⁻¹' {0}
have hk : MeasurableSet k := by borelize E; exact haux.measurable (measurableSet_singleton _)
calc
∫ x in t, f x ∂μ = ∫ x in t ∩ k, f x ∂μ + ∫ x in t \ k, f x ∂μ := by
rw [integral_inter_add_diff hk h'aux]
_ = ∫ x in t \ k, f x ∂μ := by
rw [setIntegral_eq_zero_of_forall_eq_zero fun x hx => ?_, zero_add]; exact hx.2
_ = ∫ x in s \ k, f x ∂μ := by
apply setIntegral_congr_set_ae
filter_upwards [h't] with x hx
change (x ∈ t \ k) = (x ∈ s \ k)
simp only [mem_preimage, mem_singleton_iff, eq_iff_iff, and_congr_left_iff, mem_diff]
intro h'x
by_cases xs : x ∈ s
· simp only [xs, hts xs]
· simp only [xs, iff_false_iff]
intro xt
exact h'x (hx ⟨xt, xs⟩)
_ = ∫ x in s ∩ k, f x ∂μ + ∫ x in s \ k, f x ∂μ := by
have : ∀ x ∈ s ∩ k, f x = 0 := fun x hx => hx.2
rw [setIntegral_eq_zero_of_forall_eq_zero this, zero_add]
_ = ∫ x in s, f x ∂μ := by rw [integral_inter_add_diff hk (h'aux.mono hts le_rfl)]
#align measure_theory.set_integral_eq_of_subset_of_ae_diff_eq_zero_aux MeasureTheory.setIntegral_eq_of_subset_of_ae_diff_eq_zero_aux
@[deprecated (since := "2024-04-17")]
alias set_integral_eq_of_subset_of_ae_diff_eq_zero_aux :=
setIntegral_eq_of_subset_of_ae_diff_eq_zero_aux
theorem setIntegral_eq_of_subset_of_ae_diff_eq_zero (ht : NullMeasurableSet t μ) (hts : s ⊆ t)
(h't : ∀ᵐ x ∂μ, x ∈ t \ s → f x = 0) : ∫ x in t, f x ∂μ = ∫ x in s, f x ∂μ := by
by_cases h : IntegrableOn f t μ; swap
· have : ¬IntegrableOn f s μ := fun H => h (H.of_ae_diff_eq_zero ht h't)
rw [integral_undef h, integral_undef this]
let f' := h.1.mk f
calc
∫ x in t, f x ∂μ = ∫ x in t, f' x ∂μ := integral_congr_ae h.1.ae_eq_mk
_ = ∫ x in s, f' x ∂μ := by
apply
setIntegral_eq_of_subset_of_ae_diff_eq_zero_aux hts _ h.1.stronglyMeasurable_mk
(h.congr h.1.ae_eq_mk)
filter_upwards [h't, ae_imp_of_ae_restrict h.1.ae_eq_mk] with x hx h'x h''x
rw [← h'x h''x.1, hx h''x]
_ = ∫ x in s, f x ∂μ := by
apply integral_congr_ae
apply ae_restrict_of_ae_restrict_of_subset hts
exact h.1.ae_eq_mk.symm
#align measure_theory.set_integral_eq_of_subset_of_ae_diff_eq_zero MeasureTheory.setIntegral_eq_of_subset_of_ae_diff_eq_zero
@[deprecated (since := "2024-04-17")]
alias set_integral_eq_of_subset_of_ae_diff_eq_zero := setIntegral_eq_of_subset_of_ae_diff_eq_zero
theorem setIntegral_eq_of_subset_of_forall_diff_eq_zero (ht : MeasurableSet t) (hts : s ⊆ t)
(h't : ∀ x ∈ t \ s, f x = 0) : ∫ x in t, f x ∂μ = ∫ x in s, f x ∂μ :=
setIntegral_eq_of_subset_of_ae_diff_eq_zero ht.nullMeasurableSet hts
(eventually_of_forall fun x hx => h't x hx)
#align measure_theory.set_integral_eq_of_subset_of_forall_diff_eq_zero MeasureTheory.setIntegral_eq_of_subset_of_forall_diff_eq_zero
@[deprecated (since := "2024-04-17")]
alias set_integral_eq_of_subset_of_forall_diff_eq_zero :=
setIntegral_eq_of_subset_of_forall_diff_eq_zero
theorem setIntegral_eq_integral_of_ae_compl_eq_zero (h : ∀ᵐ x ∂μ, x ∉ s → f x = 0) :
∫ x in s, f x ∂μ = ∫ x, f x ∂μ := by
symm
nth_rw 1 [← integral_univ]
apply setIntegral_eq_of_subset_of_ae_diff_eq_zero nullMeasurableSet_univ (subset_univ _)
filter_upwards [h] with x hx h'x using hx h'x.2
#align measure_theory.set_integral_eq_integral_of_ae_compl_eq_zero MeasureTheory.setIntegral_eq_integral_of_ae_compl_eq_zero
@[deprecated (since := "2024-04-17")]
alias set_integral_eq_integral_of_ae_compl_eq_zero := setIntegral_eq_integral_of_ae_compl_eq_zero
theorem setIntegral_eq_integral_of_forall_compl_eq_zero (h : ∀ x, x ∉ s → f x = 0) :
∫ x in s, f x ∂μ = ∫ x, f x ∂μ :=
setIntegral_eq_integral_of_ae_compl_eq_zero (eventually_of_forall h)
#align measure_theory.set_integral_eq_integral_of_forall_compl_eq_zero MeasureTheory.setIntegral_eq_integral_of_forall_compl_eq_zero
@[deprecated (since := "2024-04-17")]
alias set_integral_eq_integral_of_forall_compl_eq_zero :=
setIntegral_eq_integral_of_forall_compl_eq_zero
theorem setIntegral_neg_eq_setIntegral_nonpos [LinearOrder E] {f : X → E}
(hf : AEStronglyMeasurable f μ) :
∫ x in {x | f x < 0}, f x ∂μ = ∫ x in {x | f x ≤ 0}, f x ∂μ := by
have h_union : {x | f x ≤ 0} = {x | f x < 0} ∪ {x | f x = 0} := by
simp_rw [le_iff_lt_or_eq, setOf_or]
rw [h_union]
have B : NullMeasurableSet {x | f x = 0} μ :=
hf.nullMeasurableSet_eq_fun aestronglyMeasurable_zero
symm
refine integral_union_eq_left_of_ae ?_
filter_upwards [ae_restrict_mem₀ B] with x hx using hx
#align measure_theory.set_integral_neg_eq_set_integral_nonpos MeasureTheory.setIntegral_neg_eq_setIntegral_nonpos
@[deprecated (since := "2024-04-17")]
alias set_integral_neg_eq_set_integral_nonpos := setIntegral_neg_eq_setIntegral_nonpos
theorem integral_norm_eq_pos_sub_neg {f : X → ℝ} (hfi : Integrable f μ) :
∫ x, ‖f x‖ ∂μ = ∫ x in {x | 0 ≤ f x}, f x ∂μ - ∫ x in {x | f x ≤ 0}, f x ∂μ :=
have h_meas : NullMeasurableSet {x | 0 ≤ f x} μ :=
aestronglyMeasurable_const.nullMeasurableSet_le hfi.1
calc
∫ x, ‖f x‖ ∂μ = ∫ x in {x | 0 ≤ f x}, ‖f x‖ ∂μ + ∫ x in {x | 0 ≤ f x}ᶜ, ‖f x‖ ∂μ := by
rw [← integral_add_compl₀ h_meas hfi.norm]
_ = ∫ x in {x | 0 ≤ f x}, f x ∂μ + ∫ x in {x | 0 ≤ f x}ᶜ, ‖f x‖ ∂μ := by
congr 1
refine setIntegral_congr₀ h_meas fun x hx => ?_
dsimp only
rw [Real.norm_eq_abs, abs_eq_self.mpr _]
exact hx
_ = ∫ x in {x | 0 ≤ f x}, f x ∂μ - ∫ x in {x | 0 ≤ f x}ᶜ, f x ∂μ := by
congr 1
rw [← integral_neg]
refine setIntegral_congr₀ h_meas.compl fun x hx => ?_
dsimp only
rw [Real.norm_eq_abs, abs_eq_neg_self.mpr _]
rw [Set.mem_compl_iff, Set.nmem_setOf_iff] at hx
linarith
_ = ∫ x in {x | 0 ≤ f x}, f x ∂μ - ∫ x in {x | f x ≤ 0}, f x ∂μ := by
rw [← setIntegral_neg_eq_setIntegral_nonpos hfi.1, compl_setOf]; simp only [not_le]
#align measure_theory.integral_norm_eq_pos_sub_neg MeasureTheory.integral_norm_eq_pos_sub_neg
theorem setIntegral_const [CompleteSpace E] (c : E) : ∫ _ in s, c ∂μ = (μ s).toReal • c := by
rw [integral_const, Measure.restrict_apply_univ]
#align measure_theory.set_integral_const MeasureTheory.setIntegral_const
@[deprecated (since := "2024-04-17")]
alias set_integral_const := setIntegral_const
@[simp]
theorem integral_indicator_const [CompleteSpace E] (e : E) ⦃s : Set X⦄ (s_meas : MeasurableSet s) :
∫ x : X, s.indicator (fun _ : X => e) x ∂μ = (μ s).toReal • e := by
rw [integral_indicator s_meas, ← setIntegral_const]
#align measure_theory.integral_indicator_const MeasureTheory.integral_indicator_const
@[simp]
theorem integral_indicator_one ⦃s : Set X⦄ (hs : MeasurableSet s) :
∫ x, s.indicator 1 x ∂μ = (μ s).toReal :=
(integral_indicator_const 1 hs).trans ((smul_eq_mul _).trans (mul_one _))
#align measure_theory.integral_indicator_one MeasureTheory.integral_indicator_one
theorem setIntegral_indicatorConstLp [CompleteSpace E]
{p : ℝ≥0∞} (hs : MeasurableSet s) (ht : MeasurableSet t) (hμt : μ t ≠ ∞) (e : E) :
∫ x in s, indicatorConstLp p ht hμt e x ∂μ = (μ (t ∩ s)).toReal • e :=
calc
∫ x in s, indicatorConstLp p ht hμt e x ∂μ = ∫ x in s, t.indicator (fun _ => e) x ∂μ := by
rw [setIntegral_congr_ae hs (indicatorConstLp_coeFn.mono fun x hx _ => hx)]
_ = (μ (t ∩ s)).toReal • e := by rw [integral_indicator_const _ ht, Measure.restrict_apply ht]
set_option linter.uppercaseLean3 false in
#align measure_theory.set_integral_indicator_const_Lp MeasureTheory.setIntegral_indicatorConstLp
@[deprecated (since := "2024-04-17")]
alias set_integral_indicatorConstLp := setIntegral_indicatorConstLp
theorem integral_indicatorConstLp [CompleteSpace E]
{p : ℝ≥0∞} (ht : MeasurableSet t) (hμt : μ t ≠ ∞) (e : E) :
∫ x, indicatorConstLp p ht hμt e x ∂μ = (μ t).toReal • e :=
calc
∫ x, indicatorConstLp p ht hμt e x ∂μ = ∫ x in univ, indicatorConstLp p ht hμt e x ∂μ := by
rw [integral_univ]
_ = (μ (t ∩ univ)).toReal • e := setIntegral_indicatorConstLp MeasurableSet.univ ht hμt e
_ = (μ t).toReal • e := by rw [inter_univ]
set_option linter.uppercaseLean3 false in
#align measure_theory.integral_indicator_const_Lp MeasureTheory.integral_indicatorConstLp
| Mathlib/MeasureTheory/Integral/SetIntegral.lean | 566 | 571 | theorem setIntegral_map {Y} [MeasurableSpace Y] {g : X → Y} {f : Y → E} {s : Set Y}
(hs : MeasurableSet s) (hf : AEStronglyMeasurable f (Measure.map g μ)) (hg : AEMeasurable g μ) :
∫ y in s, f y ∂Measure.map g μ = ∫ x in g ⁻¹' s, f (g x) ∂μ := by |
rw [Measure.restrict_map_of_aemeasurable hg hs,
integral_map (hg.mono_measure Measure.restrict_le_self) (hf.mono_measure _)]
exact Measure.map_mono_of_aemeasurable Measure.restrict_le_self hg
|
import Mathlib.Algebra.Group.Invertible.Basic
import Mathlib.Algebra.GroupWithZero.Units.Basic
#align_import algebra.invertible from "leanprover-community/mathlib"@"722b3b152ddd5e0cf21c0a29787c76596cb6b422"
assert_not_exists DenselyOrdered
universe u
variable {α : Type u}
| Mathlib/Algebra/GroupWithZero/Invertible.lean | 23 | 28 | theorem nonzero_of_invertible [MulZeroOneClass α] (a : α) [Nontrivial α] [Invertible a] : a ≠ 0 :=
fun ha =>
zero_ne_one <|
calc
0 = ⅟ a * a := by | simp [ha]
_ = 1 := invOf_mul_self a
|
import Mathlib.Dynamics.Ergodic.MeasurePreserving
import Mathlib.MeasureTheory.Function.SimpleFunc
import Mathlib.MeasureTheory.Measure.MutuallySingular
import Mathlib.MeasureTheory.Measure.Count
import Mathlib.Topology.IndicatorConstPointwise
import Mathlib.MeasureTheory.Constructions.BorelSpace.Real
#align_import measure_theory.integral.lebesgue from "leanprover-community/mathlib"@"c14c8fcde993801fca8946b0d80131a1a81d1520"
assert_not_exists NormedSpace
set_option autoImplicit true
noncomputable section
open Set hiding restrict restrict_apply
open Filter ENNReal
open Function (support)
open scoped Classical
open Topology NNReal ENNReal MeasureTheory
namespace MeasureTheory
local infixr:25 " →ₛ " => SimpleFunc
variable {α β γ δ : Type*}
section Lintegral
open SimpleFunc
variable {m : MeasurableSpace α} {μ ν : Measure α}
irreducible_def lintegral {_ : MeasurableSpace α} (μ : Measure α) (f : α → ℝ≥0∞) : ℝ≥0∞ :=
⨆ (g : α →ₛ ℝ≥0∞) (_ : ⇑g ≤ f), g.lintegral μ
#align measure_theory.lintegral MeasureTheory.lintegral
@[inherit_doc MeasureTheory.lintegral]
notation3 "∫⁻ "(...)", "r:60:(scoped f => f)" ∂"μ:70 => lintegral μ r
@[inherit_doc MeasureTheory.lintegral]
notation3 "∫⁻ "(...)", "r:60:(scoped f => lintegral volume f) => r
@[inherit_doc MeasureTheory.lintegral]
notation3"∫⁻ "(...)" in "s", "r:60:(scoped f => f)" ∂"μ:70 => lintegral (Measure.restrict μ s) r
@[inherit_doc MeasureTheory.lintegral]
notation3"∫⁻ "(...)" in "s", "r:60:(scoped f => lintegral (Measure.restrict volume s) f) => r
theorem SimpleFunc.lintegral_eq_lintegral {m : MeasurableSpace α} (f : α →ₛ ℝ≥0∞) (μ : Measure α) :
∫⁻ a, f a ∂μ = f.lintegral μ := by
rw [MeasureTheory.lintegral]
exact le_antisymm (iSup₂_le fun g hg => lintegral_mono hg <| le_rfl)
(le_iSup₂_of_le f le_rfl le_rfl)
#align measure_theory.simple_func.lintegral_eq_lintegral MeasureTheory.SimpleFunc.lintegral_eq_lintegral
@[mono]
theorem lintegral_mono' {m : MeasurableSpace α} ⦃μ ν : Measure α⦄ (hμν : μ ≤ ν) ⦃f g : α → ℝ≥0∞⦄
(hfg : f ≤ g) : ∫⁻ a, f a ∂μ ≤ ∫⁻ a, g a ∂ν := by
rw [lintegral, lintegral]
exact iSup_mono fun φ => iSup_mono' fun hφ => ⟨le_trans hφ hfg, lintegral_mono (le_refl φ) hμν⟩
#align measure_theory.lintegral_mono' MeasureTheory.lintegral_mono'
-- workaround for the known eta-reduction issue with `@[gcongr]`
@[gcongr] theorem lintegral_mono_fn' ⦃f g : α → ℝ≥0∞⦄ (hfg : ∀ x, f x ≤ g x) (h2 : μ ≤ ν) :
lintegral μ f ≤ lintegral ν g :=
lintegral_mono' h2 hfg
theorem lintegral_mono ⦃f g : α → ℝ≥0∞⦄ (hfg : f ≤ g) : ∫⁻ a, f a ∂μ ≤ ∫⁻ a, g a ∂μ :=
lintegral_mono' (le_refl μ) hfg
#align measure_theory.lintegral_mono MeasureTheory.lintegral_mono
-- workaround for the known eta-reduction issue with `@[gcongr]`
@[gcongr] theorem lintegral_mono_fn ⦃f g : α → ℝ≥0∞⦄ (hfg : ∀ x, f x ≤ g x) :
lintegral μ f ≤ lintegral μ g :=
lintegral_mono hfg
theorem lintegral_mono_nnreal {f g : α → ℝ≥0} (h : f ≤ g) : ∫⁻ a, f a ∂μ ≤ ∫⁻ a, g a ∂μ :=
lintegral_mono fun a => ENNReal.coe_le_coe.2 (h a)
#align measure_theory.lintegral_mono_nnreal MeasureTheory.lintegral_mono_nnreal
theorem iSup_lintegral_measurable_le_eq_lintegral (f : α → ℝ≥0∞) :
⨆ (g : α → ℝ≥0∞) (_ : Measurable g) (_ : g ≤ f), ∫⁻ a, g a ∂μ = ∫⁻ a, f a ∂μ := by
apply le_antisymm
· exact iSup_le fun i => iSup_le fun _ => iSup_le fun h'i => lintegral_mono h'i
· rw [lintegral]
refine iSup₂_le fun i hi => le_iSup₂_of_le i i.measurable <| le_iSup_of_le hi ?_
exact le_of_eq (i.lintegral_eq_lintegral _).symm
#align measure_theory.supr_lintegral_measurable_le_eq_lintegral MeasureTheory.iSup_lintegral_measurable_le_eq_lintegral
theorem lintegral_mono_set {_ : MeasurableSpace α} ⦃μ : Measure α⦄ {s t : Set α} {f : α → ℝ≥0∞}
(hst : s ⊆ t) : ∫⁻ x in s, f x ∂μ ≤ ∫⁻ x in t, f x ∂μ :=
lintegral_mono' (Measure.restrict_mono hst (le_refl μ)) (le_refl f)
#align measure_theory.lintegral_mono_set MeasureTheory.lintegral_mono_set
theorem lintegral_mono_set' {_ : MeasurableSpace α} ⦃μ : Measure α⦄ {s t : Set α} {f : α → ℝ≥0∞}
(hst : s ≤ᵐ[μ] t) : ∫⁻ x in s, f x ∂μ ≤ ∫⁻ x in t, f x ∂μ :=
lintegral_mono' (Measure.restrict_mono' hst (le_refl μ)) (le_refl f)
#align measure_theory.lintegral_mono_set' MeasureTheory.lintegral_mono_set'
theorem monotone_lintegral {_ : MeasurableSpace α} (μ : Measure α) : Monotone (lintegral μ) :=
lintegral_mono
#align measure_theory.monotone_lintegral MeasureTheory.monotone_lintegral
@[simp]
theorem lintegral_const (c : ℝ≥0∞) : ∫⁻ _, c ∂μ = c * μ univ := by
rw [← SimpleFunc.const_lintegral, ← SimpleFunc.lintegral_eq_lintegral, SimpleFunc.coe_const]
rfl
#align measure_theory.lintegral_const MeasureTheory.lintegral_const
theorem lintegral_zero : ∫⁻ _ : α, 0 ∂μ = 0 := by simp
#align measure_theory.lintegral_zero MeasureTheory.lintegral_zero
theorem lintegral_zero_fun : lintegral μ (0 : α → ℝ≥0∞) = 0 :=
lintegral_zero
#align measure_theory.lintegral_zero_fun MeasureTheory.lintegral_zero_fun
-- @[simp] -- Porting note (#10618): simp can prove this
theorem lintegral_one : ∫⁻ _, (1 : ℝ≥0∞) ∂μ = μ univ := by rw [lintegral_const, one_mul]
#align measure_theory.lintegral_one MeasureTheory.lintegral_one
theorem set_lintegral_const (s : Set α) (c : ℝ≥0∞) : ∫⁻ _ in s, c ∂μ = c * μ s := by
rw [lintegral_const, Measure.restrict_apply_univ]
#align measure_theory.set_lintegral_const MeasureTheory.set_lintegral_const
theorem set_lintegral_one (s) : ∫⁻ _ in s, 1 ∂μ = μ s := by rw [set_lintegral_const, one_mul]
#align measure_theory.set_lintegral_one MeasureTheory.set_lintegral_one
theorem set_lintegral_const_lt_top [IsFiniteMeasure μ] (s : Set α) {c : ℝ≥0∞} (hc : c ≠ ∞) :
∫⁻ _ in s, c ∂μ < ∞ := by
rw [lintegral_const]
exact ENNReal.mul_lt_top hc (measure_ne_top (μ.restrict s) univ)
#align measure_theory.set_lintegral_const_lt_top MeasureTheory.set_lintegral_const_lt_top
theorem lintegral_const_lt_top [IsFiniteMeasure μ] {c : ℝ≥0∞} (hc : c ≠ ∞) : ∫⁻ _, c ∂μ < ∞ := by
simpa only [Measure.restrict_univ] using set_lintegral_const_lt_top (univ : Set α) hc
#align measure_theory.lintegral_const_lt_top MeasureTheory.lintegral_const_lt_top
section
variable (μ)
theorem exists_measurable_le_lintegral_eq (f : α → ℝ≥0∞) :
∃ g : α → ℝ≥0∞, Measurable g ∧ g ≤ f ∧ ∫⁻ a, f a ∂μ = ∫⁻ a, g a ∂μ := by
rcases eq_or_ne (∫⁻ a, f a ∂μ) 0 with h₀ | h₀
· exact ⟨0, measurable_zero, zero_le f, h₀.trans lintegral_zero.symm⟩
rcases exists_seq_strictMono_tendsto' h₀.bot_lt with ⟨L, _, hLf, hL_tendsto⟩
have : ∀ n, ∃ g : α → ℝ≥0∞, Measurable g ∧ g ≤ f ∧ L n < ∫⁻ a, g a ∂μ := by
intro n
simpa only [← iSup_lintegral_measurable_le_eq_lintegral f, lt_iSup_iff, exists_prop] using
(hLf n).2
choose g hgm hgf hLg using this
refine
⟨fun x => ⨆ n, g n x, measurable_iSup hgm, fun x => iSup_le fun n => hgf n x, le_antisymm ?_ ?_⟩
· refine le_of_tendsto' hL_tendsto fun n => (hLg n).le.trans <| lintegral_mono fun x => ?_
exact le_iSup (fun n => g n x) n
· exact lintegral_mono fun x => iSup_le fun n => hgf n x
#align measure_theory.exists_measurable_le_lintegral_eq MeasureTheory.exists_measurable_le_lintegral_eq
end
theorem lintegral_eq_nnreal {m : MeasurableSpace α} (f : α → ℝ≥0∞) (μ : Measure α) :
∫⁻ a, f a ∂μ =
⨆ (φ : α →ₛ ℝ≥0) (_ : ∀ x, ↑(φ x) ≤ f x), (φ.map ((↑) : ℝ≥0 → ℝ≥0∞)).lintegral μ := by
rw [lintegral]
refine
le_antisymm (iSup₂_le fun φ hφ => ?_) (iSup_mono' fun φ => ⟨φ.map ((↑) : ℝ≥0 → ℝ≥0∞), le_rfl⟩)
by_cases h : ∀ᵐ a ∂μ, φ a ≠ ∞
· let ψ := φ.map ENNReal.toNNReal
replace h : ψ.map ((↑) : ℝ≥0 → ℝ≥0∞) =ᵐ[μ] φ := h.mono fun a => ENNReal.coe_toNNReal
have : ∀ x, ↑(ψ x) ≤ f x := fun x => le_trans ENNReal.coe_toNNReal_le_self (hφ x)
exact
le_iSup_of_le (φ.map ENNReal.toNNReal) (le_iSup_of_le this (ge_of_eq <| lintegral_congr h))
· have h_meas : μ (φ ⁻¹' {∞}) ≠ 0 := mt measure_zero_iff_ae_nmem.1 h
refine le_trans le_top (ge_of_eq <| (iSup_eq_top _).2 fun b hb => ?_)
obtain ⟨n, hn⟩ : ∃ n : ℕ, b < n * μ (φ ⁻¹' {∞}) := exists_nat_mul_gt h_meas (ne_of_lt hb)
use (const α (n : ℝ≥0)).restrict (φ ⁻¹' {∞})
simp only [lt_iSup_iff, exists_prop, coe_restrict, φ.measurableSet_preimage, coe_const,
ENNReal.coe_indicator, map_coe_ennreal_restrict, SimpleFunc.map_const, ENNReal.coe_natCast,
restrict_const_lintegral]
refine ⟨indicator_le fun x hx => le_trans ?_ (hφ _), hn⟩
simp only [mem_preimage, mem_singleton_iff] at hx
simp only [hx, le_top]
#align measure_theory.lintegral_eq_nnreal MeasureTheory.lintegral_eq_nnreal
theorem exists_simpleFunc_forall_lintegral_sub_lt_of_pos {f : α → ℝ≥0∞} (h : ∫⁻ x, f x ∂μ ≠ ∞)
{ε : ℝ≥0∞} (hε : ε ≠ 0) :
∃ φ : α →ₛ ℝ≥0,
(∀ x, ↑(φ x) ≤ f x) ∧
∀ ψ : α →ₛ ℝ≥0, (∀ x, ↑(ψ x) ≤ f x) → (map (↑) (ψ - φ)).lintegral μ < ε := by
rw [lintegral_eq_nnreal] at h
have := ENNReal.lt_add_right h hε
erw [ENNReal.biSup_add] at this <;> [skip; exact ⟨0, fun x => zero_le _⟩]
simp_rw [lt_iSup_iff, iSup_lt_iff, iSup_le_iff] at this
rcases this with ⟨φ, hle : ∀ x, ↑(φ x) ≤ f x, b, hbφ, hb⟩
refine ⟨φ, hle, fun ψ hψ => ?_⟩
have : (map (↑) φ).lintegral μ ≠ ∞ := ne_top_of_le_ne_top h (by exact le_iSup₂ (α := ℝ≥0∞) φ hle)
rw [← ENNReal.add_lt_add_iff_left this, ← add_lintegral, ← SimpleFunc.map_add @ENNReal.coe_add]
refine (hb _ fun x => le_trans ?_ (max_le (hle x) (hψ x))).trans_lt hbφ
norm_cast
simp only [add_apply, sub_apply, add_tsub_eq_max]
rfl
#align measure_theory.exists_simple_func_forall_lintegral_sub_lt_of_pos MeasureTheory.exists_simpleFunc_forall_lintegral_sub_lt_of_pos
theorem iSup_lintegral_le {ι : Sort*} (f : ι → α → ℝ≥0∞) :
⨆ i, ∫⁻ a, f i a ∂μ ≤ ∫⁻ a, ⨆ i, f i a ∂μ := by
simp only [← iSup_apply]
exact (monotone_lintegral μ).le_map_iSup
#align measure_theory.supr_lintegral_le MeasureTheory.iSup_lintegral_le
theorem iSup₂_lintegral_le {ι : Sort*} {ι' : ι → Sort*} (f : ∀ i, ι' i → α → ℝ≥0∞) :
⨆ (i) (j), ∫⁻ a, f i j a ∂μ ≤ ∫⁻ a, ⨆ (i) (j), f i j a ∂μ := by
convert (monotone_lintegral μ).le_map_iSup₂ f with a
simp only [iSup_apply]
#align measure_theory.supr₂_lintegral_le MeasureTheory.iSup₂_lintegral_le
theorem le_iInf_lintegral {ι : Sort*} (f : ι → α → ℝ≥0∞) :
∫⁻ a, ⨅ i, f i a ∂μ ≤ ⨅ i, ∫⁻ a, f i a ∂μ := by
simp only [← iInf_apply]
exact (monotone_lintegral μ).map_iInf_le
#align measure_theory.le_infi_lintegral MeasureTheory.le_iInf_lintegral
theorem le_iInf₂_lintegral {ι : Sort*} {ι' : ι → Sort*} (f : ∀ i, ι' i → α → ℝ≥0∞) :
∫⁻ a, ⨅ (i) (h : ι' i), f i h a ∂μ ≤ ⨅ (i) (h : ι' i), ∫⁻ a, f i h a ∂μ := by
convert (monotone_lintegral μ).map_iInf₂_le f with a
simp only [iInf_apply]
#align measure_theory.le_infi₂_lintegral MeasureTheory.le_iInf₂_lintegral
theorem lintegral_mono_ae {f g : α → ℝ≥0∞} (h : ∀ᵐ a ∂μ, f a ≤ g a) :
∫⁻ a, f a ∂μ ≤ ∫⁻ a, g a ∂μ := by
rcases exists_measurable_superset_of_null h with ⟨t, hts, ht, ht0⟩
have : ∀ᵐ x ∂μ, x ∉ t := measure_zero_iff_ae_nmem.1 ht0
rw [lintegral, lintegral]
refine iSup_le fun s => iSup_le fun hfs => le_iSup_of_le (s.restrict tᶜ) <| le_iSup_of_le ?_ ?_
· intro a
by_cases h : a ∈ t <;>
simp only [restrict_apply s ht.compl, mem_compl_iff, h, not_true, not_false_eq_true,
indicator_of_not_mem, zero_le, not_false_eq_true, indicator_of_mem]
exact le_trans (hfs a) (_root_.by_contradiction fun hnfg => h (hts hnfg))
· refine le_of_eq (SimpleFunc.lintegral_congr <| this.mono fun a hnt => ?_)
by_cases hat : a ∈ t <;> simp only [restrict_apply s ht.compl, mem_compl_iff, hat, not_true,
not_false_eq_true, indicator_of_not_mem, not_false_eq_true, indicator_of_mem]
exact (hnt hat).elim
#align measure_theory.lintegral_mono_ae MeasureTheory.lintegral_mono_ae
theorem set_lintegral_mono_ae {s : Set α} {f g : α → ℝ≥0∞} (hf : Measurable f) (hg : Measurable g)
(hfg : ∀ᵐ x ∂μ, x ∈ s → f x ≤ g x) : ∫⁻ x in s, f x ∂μ ≤ ∫⁻ x in s, g x ∂μ :=
lintegral_mono_ae <| (ae_restrict_iff <| measurableSet_le hf hg).2 hfg
#align measure_theory.set_lintegral_mono_ae MeasureTheory.set_lintegral_mono_ae
theorem set_lintegral_mono {s : Set α} {f g : α → ℝ≥0∞} (hf : Measurable f) (hg : Measurable g)
(hfg : ∀ x ∈ s, f x ≤ g x) : ∫⁻ x in s, f x ∂μ ≤ ∫⁻ x in s, g x ∂μ :=
set_lintegral_mono_ae hf hg (ae_of_all _ hfg)
#align measure_theory.set_lintegral_mono MeasureTheory.set_lintegral_mono
theorem set_lintegral_mono_ae' {s : Set α} {f g : α → ℝ≥0∞} (hs : MeasurableSet s)
(hfg : ∀ᵐ x ∂μ, x ∈ s → f x ≤ g x) : ∫⁻ x in s, f x ∂μ ≤ ∫⁻ x in s, g x ∂μ :=
lintegral_mono_ae <| (ae_restrict_iff' hs).2 hfg
theorem set_lintegral_mono' {s : Set α} {f g : α → ℝ≥0∞} (hs : MeasurableSet s)
(hfg : ∀ x ∈ s, f x ≤ g x) : ∫⁻ x in s, f x ∂μ ≤ ∫⁻ x in s, g x ∂μ :=
set_lintegral_mono_ae' hs (ae_of_all _ hfg)
theorem set_lintegral_le_lintegral (s : Set α) (f : α → ℝ≥0∞) :
∫⁻ x in s, f x ∂μ ≤ ∫⁻ x, f x ∂μ :=
lintegral_mono' Measure.restrict_le_self le_rfl
theorem lintegral_congr_ae {f g : α → ℝ≥0∞} (h : f =ᵐ[μ] g) : ∫⁻ a, f a ∂μ = ∫⁻ a, g a ∂μ :=
le_antisymm (lintegral_mono_ae <| h.le) (lintegral_mono_ae <| h.symm.le)
#align measure_theory.lintegral_congr_ae MeasureTheory.lintegral_congr_ae
theorem lintegral_congr {f g : α → ℝ≥0∞} (h : ∀ a, f a = g a) : ∫⁻ a, f a ∂μ = ∫⁻ a, g a ∂μ := by
simp only [h]
#align measure_theory.lintegral_congr MeasureTheory.lintegral_congr
theorem set_lintegral_congr {f : α → ℝ≥0∞} {s t : Set α} (h : s =ᵐ[μ] t) :
∫⁻ x in s, f x ∂μ = ∫⁻ x in t, f x ∂μ := by rw [Measure.restrict_congr_set h]
#align measure_theory.set_lintegral_congr MeasureTheory.set_lintegral_congr
theorem set_lintegral_congr_fun {f g : α → ℝ≥0∞} {s : Set α} (hs : MeasurableSet s)
(hfg : ∀ᵐ x ∂μ, x ∈ s → f x = g x) : ∫⁻ x in s, f x ∂μ = ∫⁻ x in s, g x ∂μ := by
rw [lintegral_congr_ae]
rw [EventuallyEq]
rwa [ae_restrict_iff' hs]
#align measure_theory.set_lintegral_congr_fun MeasureTheory.set_lintegral_congr_fun
theorem lintegral_ofReal_le_lintegral_nnnorm (f : α → ℝ) :
∫⁻ x, ENNReal.ofReal (f x) ∂μ ≤ ∫⁻ x, ‖f x‖₊ ∂μ := by
simp_rw [← ofReal_norm_eq_coe_nnnorm]
refine lintegral_mono fun x => ENNReal.ofReal_le_ofReal ?_
rw [Real.norm_eq_abs]
exact le_abs_self (f x)
#align measure_theory.lintegral_of_real_le_lintegral_nnnorm MeasureTheory.lintegral_ofReal_le_lintegral_nnnorm
theorem lintegral_nnnorm_eq_of_ae_nonneg {f : α → ℝ} (h_nonneg : 0 ≤ᵐ[μ] f) :
∫⁻ x, ‖f x‖₊ ∂μ = ∫⁻ x, ENNReal.ofReal (f x) ∂μ := by
apply lintegral_congr_ae
filter_upwards [h_nonneg] with x hx
rw [Real.nnnorm_of_nonneg hx, ENNReal.ofReal_eq_coe_nnreal hx]
#align measure_theory.lintegral_nnnorm_eq_of_ae_nonneg MeasureTheory.lintegral_nnnorm_eq_of_ae_nonneg
theorem lintegral_nnnorm_eq_of_nonneg {f : α → ℝ} (h_nonneg : 0 ≤ f) :
∫⁻ x, ‖f x‖₊ ∂μ = ∫⁻ x, ENNReal.ofReal (f x) ∂μ :=
lintegral_nnnorm_eq_of_ae_nonneg (Filter.eventually_of_forall h_nonneg)
#align measure_theory.lintegral_nnnorm_eq_of_nonneg MeasureTheory.lintegral_nnnorm_eq_of_nonneg
theorem lintegral_iSup {f : ℕ → α → ℝ≥0∞} (hf : ∀ n, Measurable (f n)) (h_mono : Monotone f) :
∫⁻ a, ⨆ n, f n a ∂μ = ⨆ n, ∫⁻ a, f n a ∂μ := by
set c : ℝ≥0 → ℝ≥0∞ := (↑)
set F := fun a : α => ⨆ n, f n a
refine le_antisymm ?_ (iSup_lintegral_le _)
rw [lintegral_eq_nnreal]
refine iSup_le fun s => iSup_le fun hsf => ?_
refine ENNReal.le_of_forall_lt_one_mul_le fun a ha => ?_
rcases ENNReal.lt_iff_exists_coe.1 ha with ⟨r, rfl, _⟩
have ha : r < 1 := ENNReal.coe_lt_coe.1 ha
let rs := s.map fun a => r * a
have eq_rs : rs.map c = (const α r : α →ₛ ℝ≥0∞) * map c s := rfl
have eq : ∀ p, rs.map c ⁻¹' {p} = ⋃ n, rs.map c ⁻¹' {p} ∩ { a | p ≤ f n a } := by
intro p
rw [← inter_iUnion]; nth_rw 1 [← inter_univ (map c rs ⁻¹' {p})]
refine Set.ext fun x => and_congr_right fun hx => true_iff_iff.2 ?_
by_cases p_eq : p = 0
· simp [p_eq]
simp only [coe_map, mem_preimage, Function.comp_apply, mem_singleton_iff] at hx
subst hx
have : r * s x ≠ 0 := by rwa [Ne, ← ENNReal.coe_eq_zero]
have : s x ≠ 0 := right_ne_zero_of_mul this
have : (rs.map c) x < ⨆ n : ℕ, f n x := by
refine lt_of_lt_of_le (ENNReal.coe_lt_coe.2 ?_) (hsf x)
suffices r * s x < 1 * s x by simpa
exact mul_lt_mul_of_pos_right ha (pos_iff_ne_zero.2 this)
rcases lt_iSup_iff.1 this with ⟨i, hi⟩
exact mem_iUnion.2 ⟨i, le_of_lt hi⟩
have mono : ∀ r : ℝ≥0∞, Monotone fun n => rs.map c ⁻¹' {r} ∩ { a | r ≤ f n a } := by
intro r i j h
refine inter_subset_inter_right _ ?_
simp_rw [subset_def, mem_setOf]
intro x hx
exact le_trans hx (h_mono h x)
have h_meas : ∀ n, MeasurableSet {a : α | map c rs a ≤ f n a} := fun n =>
measurableSet_le (SimpleFunc.measurable _) (hf n)
calc
(r : ℝ≥0∞) * (s.map c).lintegral μ = ∑ r ∈ (rs.map c).range, r * μ (rs.map c ⁻¹' {r}) := by
rw [← const_mul_lintegral, eq_rs, SimpleFunc.lintegral]
_ = ∑ r ∈ (rs.map c).range, r * μ (⋃ n, rs.map c ⁻¹' {r} ∩ { a | r ≤ f n a }) := by
simp only [(eq _).symm]
_ = ∑ r ∈ (rs.map c).range, ⨆ n, r * μ (rs.map c ⁻¹' {r} ∩ { a | r ≤ f n a }) :=
(Finset.sum_congr rfl fun x _ => by
rw [measure_iUnion_eq_iSup (mono x).directed_le, ENNReal.mul_iSup])
_ = ⨆ n, ∑ r ∈ (rs.map c).range, r * μ (rs.map c ⁻¹' {r} ∩ { a | r ≤ f n a }) := by
refine ENNReal.finset_sum_iSup_nat fun p i j h ↦ ?_
gcongr _ * μ ?_
exact mono p h
_ ≤ ⨆ n : ℕ, ((rs.map c).restrict { a | (rs.map c) a ≤ f n a }).lintegral μ := by
gcongr with n
rw [restrict_lintegral _ (h_meas n)]
refine le_of_eq (Finset.sum_congr rfl fun r _ => ?_)
congr 2 with a
refine and_congr_right ?_
simp (config := { contextual := true })
_ ≤ ⨆ n, ∫⁻ a, f n a ∂μ := by
simp only [← SimpleFunc.lintegral_eq_lintegral]
gcongr with n a
simp only [map_apply] at h_meas
simp only [coe_map, restrict_apply _ (h_meas _), (· ∘ ·)]
exact indicator_apply_le id
#align measure_theory.lintegral_supr MeasureTheory.lintegral_iSup
theorem lintegral_iSup' {f : ℕ → α → ℝ≥0∞} (hf : ∀ n, AEMeasurable (f n) μ)
(h_mono : ∀ᵐ x ∂μ, Monotone fun n => f n x) : ∫⁻ a, ⨆ n, f n a ∂μ = ⨆ n, ∫⁻ a, f n a ∂μ := by
simp_rw [← iSup_apply]
let p : α → (ℕ → ℝ≥0∞) → Prop := fun _ f' => Monotone f'
have hp : ∀ᵐ x ∂μ, p x fun i => f i x := h_mono
have h_ae_seq_mono : Monotone (aeSeq hf p) := by
intro n m hnm x
by_cases hx : x ∈ aeSeqSet hf p
· exact aeSeq.prop_of_mem_aeSeqSet hf hx hnm
· simp only [aeSeq, hx, if_false, le_rfl]
rw [lintegral_congr_ae (aeSeq.iSup hf hp).symm]
simp_rw [iSup_apply]
rw [lintegral_iSup (aeSeq.measurable hf p) h_ae_seq_mono]
congr with n
exact lintegral_congr_ae (aeSeq.aeSeq_n_eq_fun_n_ae hf hp n)
#align measure_theory.lintegral_supr' MeasureTheory.lintegral_iSup'
theorem lintegral_tendsto_of_tendsto_of_monotone {f : ℕ → α → ℝ≥0∞} {F : α → ℝ≥0∞}
(hf : ∀ n, AEMeasurable (f n) μ) (h_mono : ∀ᵐ x ∂μ, Monotone fun n => f n x)
(h_tendsto : ∀ᵐ x ∂μ, Tendsto (fun n => f n x) atTop (𝓝 <| F x)) :
Tendsto (fun n => ∫⁻ x, f n x ∂μ) atTop (𝓝 <| ∫⁻ x, F x ∂μ) := by
have : Monotone fun n => ∫⁻ x, f n x ∂μ := fun i j hij =>
lintegral_mono_ae (h_mono.mono fun x hx => hx hij)
suffices key : ∫⁻ x, F x ∂μ = ⨆ n, ∫⁻ x, f n x ∂μ by
rw [key]
exact tendsto_atTop_iSup this
rw [← lintegral_iSup' hf h_mono]
refine lintegral_congr_ae ?_
filter_upwards [h_mono, h_tendsto] with _ hx_mono hx_tendsto using
tendsto_nhds_unique hx_tendsto (tendsto_atTop_iSup hx_mono)
#align measure_theory.lintegral_tendsto_of_tendsto_of_monotone MeasureTheory.lintegral_tendsto_of_tendsto_of_monotone
theorem lintegral_eq_iSup_eapprox_lintegral {f : α → ℝ≥0∞} (hf : Measurable f) :
∫⁻ a, f a ∂μ = ⨆ n, (eapprox f n).lintegral μ :=
calc
∫⁻ a, f a ∂μ = ∫⁻ a, ⨆ n, (eapprox f n : α → ℝ≥0∞) a ∂μ := by
congr; ext a; rw [iSup_eapprox_apply f hf]
_ = ⨆ n, ∫⁻ a, (eapprox f n : α → ℝ≥0∞) a ∂μ := by
apply lintegral_iSup
· measurability
· intro i j h
exact monotone_eapprox f h
_ = ⨆ n, (eapprox f n).lintegral μ := by
congr; ext n; rw [(eapprox f n).lintegral_eq_lintegral]
#align measure_theory.lintegral_eq_supr_eapprox_lintegral MeasureTheory.lintegral_eq_iSup_eapprox_lintegral
theorem exists_pos_set_lintegral_lt_of_measure_lt {f : α → ℝ≥0∞} (h : ∫⁻ x, f x ∂μ ≠ ∞) {ε : ℝ≥0∞}
(hε : ε ≠ 0) : ∃ δ > 0, ∀ s, μ s < δ → ∫⁻ x in s, f x ∂μ < ε := by
rcases exists_between (pos_iff_ne_zero.mpr hε) with ⟨ε₂, hε₂0, hε₂ε⟩
rcases exists_between hε₂0 with ⟨ε₁, hε₁0, hε₁₂⟩
rcases exists_simpleFunc_forall_lintegral_sub_lt_of_pos h hε₁0.ne' with ⟨φ, _, hφ⟩
rcases φ.exists_forall_le with ⟨C, hC⟩
use (ε₂ - ε₁) / C, ENNReal.div_pos_iff.2 ⟨(tsub_pos_iff_lt.2 hε₁₂).ne', ENNReal.coe_ne_top⟩
refine fun s hs => lt_of_le_of_lt ?_ hε₂ε
simp only [lintegral_eq_nnreal, iSup_le_iff]
intro ψ hψ
calc
(map (↑) ψ).lintegral (μ.restrict s) ≤
(map (↑) φ).lintegral (μ.restrict s) + (map (↑) (ψ - φ)).lintegral (μ.restrict s) := by
rw [← SimpleFunc.add_lintegral, ← SimpleFunc.map_add @ENNReal.coe_add]
refine SimpleFunc.lintegral_mono (fun x => ?_) le_rfl
simp only [add_tsub_eq_max, le_max_right, coe_map, Function.comp_apply, SimpleFunc.coe_add,
SimpleFunc.coe_sub, Pi.add_apply, Pi.sub_apply, ENNReal.coe_max (φ x) (ψ x)]
_ ≤ (map (↑) φ).lintegral (μ.restrict s) + ε₁ := by
gcongr
refine le_trans ?_ (hφ _ hψ).le
exact SimpleFunc.lintegral_mono le_rfl Measure.restrict_le_self
_ ≤ (SimpleFunc.const α (C : ℝ≥0∞)).lintegral (μ.restrict s) + ε₁ := by
gcongr
exact SimpleFunc.lintegral_mono (fun x ↦ ENNReal.coe_le_coe.2 (hC x)) le_rfl
_ = C * μ s + ε₁ := by
simp only [← SimpleFunc.lintegral_eq_lintegral, coe_const, lintegral_const,
Measure.restrict_apply, MeasurableSet.univ, univ_inter, Function.const]
_ ≤ C * ((ε₂ - ε₁) / C) + ε₁ := by gcongr
_ ≤ ε₂ - ε₁ + ε₁ := by gcongr; apply mul_div_le
_ = ε₂ := tsub_add_cancel_of_le hε₁₂.le
#align measure_theory.exists_pos_set_lintegral_lt_of_measure_lt MeasureTheory.exists_pos_set_lintegral_lt_of_measure_lt
theorem tendsto_set_lintegral_zero {ι} {f : α → ℝ≥0∞} (h : ∫⁻ x, f x ∂μ ≠ ∞) {l : Filter ι}
{s : ι → Set α} (hl : Tendsto (μ ∘ s) l (𝓝 0)) :
Tendsto (fun i => ∫⁻ x in s i, f x ∂μ) l (𝓝 0) := by
simp only [ENNReal.nhds_zero, tendsto_iInf, tendsto_principal, mem_Iio,
← pos_iff_ne_zero] at hl ⊢
intro ε ε0
rcases exists_pos_set_lintegral_lt_of_measure_lt h ε0.ne' with ⟨δ, δ0, hδ⟩
exact (hl δ δ0).mono fun i => hδ _
#align measure_theory.tendsto_set_lintegral_zero MeasureTheory.tendsto_set_lintegral_zero
theorem le_lintegral_add (f g : α → ℝ≥0∞) :
∫⁻ a, f a ∂μ + ∫⁻ a, g a ∂μ ≤ ∫⁻ a, f a + g a ∂μ := by
simp only [lintegral]
refine ENNReal.biSup_add_biSup_le' (p := fun h : α →ₛ ℝ≥0∞ => h ≤ f)
(q := fun h : α →ₛ ℝ≥0∞ => h ≤ g) ⟨0, zero_le f⟩ ⟨0, zero_le g⟩ fun f' hf' g' hg' => ?_
exact le_iSup₂_of_le (f' + g') (add_le_add hf' hg') (add_lintegral _ _).ge
#align measure_theory.le_lintegral_add MeasureTheory.le_lintegral_add
-- Use stronger lemmas `lintegral_add_left`/`lintegral_add_right` instead
theorem lintegral_add_aux {f g : α → ℝ≥0∞} (hf : Measurable f) (hg : Measurable g) :
∫⁻ a, f a + g a ∂μ = ∫⁻ a, f a ∂μ + ∫⁻ a, g a ∂μ :=
calc
∫⁻ a, f a + g a ∂μ =
∫⁻ a, (⨆ n, (eapprox f n : α → ℝ≥0∞) a) + ⨆ n, (eapprox g n : α → ℝ≥0∞) a ∂μ := by
simp only [iSup_eapprox_apply, hf, hg]
_ = ∫⁻ a, ⨆ n, (eapprox f n + eapprox g n : α → ℝ≥0∞) a ∂μ := by
congr; funext a
rw [ENNReal.iSup_add_iSup_of_monotone]
· simp only [Pi.add_apply]
· intro i j h
exact monotone_eapprox _ h a
· intro i j h
exact monotone_eapprox _ h a
_ = ⨆ n, (eapprox f n).lintegral μ + (eapprox g n).lintegral μ := by
rw [lintegral_iSup]
· congr
funext n
rw [← SimpleFunc.add_lintegral, ← SimpleFunc.lintegral_eq_lintegral]
simp only [Pi.add_apply, SimpleFunc.coe_add]
· measurability
· intro i j h a
dsimp
gcongr <;> exact monotone_eapprox _ h _
_ = (⨆ n, (eapprox f n).lintegral μ) + ⨆ n, (eapprox g n).lintegral μ := by
refine (ENNReal.iSup_add_iSup_of_monotone ?_ ?_).symm <;>
· intro i j h
exact SimpleFunc.lintegral_mono (monotone_eapprox _ h) le_rfl
_ = ∫⁻ a, f a ∂μ + ∫⁻ a, g a ∂μ := by
rw [lintegral_eq_iSup_eapprox_lintegral hf, lintegral_eq_iSup_eapprox_lintegral hg]
#align measure_theory.lintegral_add_aux MeasureTheory.lintegral_add_aux
@[simp]
theorem lintegral_add_left {f : α → ℝ≥0∞} (hf : Measurable f) (g : α → ℝ≥0∞) :
∫⁻ a, f a + g a ∂μ = ∫⁻ a, f a ∂μ + ∫⁻ a, g a ∂μ := by
refine le_antisymm ?_ (le_lintegral_add _ _)
rcases exists_measurable_le_lintegral_eq μ fun a => f a + g a with ⟨φ, hφm, hφ_le, hφ_eq⟩
calc
∫⁻ a, f a + g a ∂μ = ∫⁻ a, φ a ∂μ := hφ_eq
_ ≤ ∫⁻ a, f a + (φ a - f a) ∂μ := lintegral_mono fun a => le_add_tsub
_ = ∫⁻ a, f a ∂μ + ∫⁻ a, φ a - f a ∂μ := lintegral_add_aux hf (hφm.sub hf)
_ ≤ ∫⁻ a, f a ∂μ + ∫⁻ a, g a ∂μ :=
add_le_add_left (lintegral_mono fun a => tsub_le_iff_left.2 <| hφ_le a) _
#align measure_theory.lintegral_add_left MeasureTheory.lintegral_add_left
theorem lintegral_add_left' {f : α → ℝ≥0∞} (hf : AEMeasurable f μ) (g : α → ℝ≥0∞) :
∫⁻ a, f a + g a ∂μ = ∫⁻ a, f a ∂μ + ∫⁻ a, g a ∂μ := by
rw [lintegral_congr_ae hf.ae_eq_mk, ← lintegral_add_left hf.measurable_mk,
lintegral_congr_ae (hf.ae_eq_mk.add (ae_eq_refl g))]
#align measure_theory.lintegral_add_left' MeasureTheory.lintegral_add_left'
theorem lintegral_add_right' (f : α → ℝ≥0∞) {g : α → ℝ≥0∞} (hg : AEMeasurable g μ) :
∫⁻ a, f a + g a ∂μ = ∫⁻ a, f a ∂μ + ∫⁻ a, g a ∂μ := by
simpa only [add_comm] using lintegral_add_left' hg f
#align measure_theory.lintegral_add_right' MeasureTheory.lintegral_add_right'
@[simp]
theorem lintegral_add_right (f : α → ℝ≥0∞) {g : α → ℝ≥0∞} (hg : Measurable g) :
∫⁻ a, f a + g a ∂μ = ∫⁻ a, f a ∂μ + ∫⁻ a, g a ∂μ :=
lintegral_add_right' f hg.aemeasurable
#align measure_theory.lintegral_add_right MeasureTheory.lintegral_add_right
@[simp]
theorem lintegral_smul_measure (c : ℝ≥0∞) (f : α → ℝ≥0∞) : ∫⁻ a, f a ∂c • μ = c * ∫⁻ a, f a ∂μ := by
simp only [lintegral, iSup_subtype', SimpleFunc.lintegral_smul, ENNReal.mul_iSup, smul_eq_mul]
#align measure_theory.lintegral_smul_measure MeasureTheory.lintegral_smul_measure
lemma set_lintegral_smul_measure (c : ℝ≥0∞) (f : α → ℝ≥0∞) (s : Set α) :
∫⁻ a in s, f a ∂(c • μ) = c * ∫⁻ a in s, f a ∂μ := by
rw [Measure.restrict_smul, lintegral_smul_measure]
@[simp]
theorem lintegral_sum_measure {m : MeasurableSpace α} {ι} (f : α → ℝ≥0∞) (μ : ι → Measure α) :
∫⁻ a, f a ∂Measure.sum μ = ∑' i, ∫⁻ a, f a ∂μ i := by
simp only [lintegral, iSup_subtype', SimpleFunc.lintegral_sum, ENNReal.tsum_eq_iSup_sum]
rw [iSup_comm]
congr; funext s
induction' s using Finset.induction_on with i s hi hs
· simp
simp only [Finset.sum_insert hi, ← hs]
refine (ENNReal.iSup_add_iSup ?_).symm
intro φ ψ
exact
⟨⟨φ ⊔ ψ, fun x => sup_le (φ.2 x) (ψ.2 x)⟩,
add_le_add (SimpleFunc.lintegral_mono le_sup_left le_rfl)
(Finset.sum_le_sum fun j _ => SimpleFunc.lintegral_mono le_sup_right le_rfl)⟩
#align measure_theory.lintegral_sum_measure MeasureTheory.lintegral_sum_measure
theorem hasSum_lintegral_measure {ι} {_ : MeasurableSpace α} (f : α → ℝ≥0∞) (μ : ι → Measure α) :
HasSum (fun i => ∫⁻ a, f a ∂μ i) (∫⁻ a, f a ∂Measure.sum μ) :=
(lintegral_sum_measure f μ).symm ▸ ENNReal.summable.hasSum
#align measure_theory.has_sum_lintegral_measure MeasureTheory.hasSum_lintegral_measure
@[simp]
theorem lintegral_add_measure {m : MeasurableSpace α} (f : α → ℝ≥0∞) (μ ν : Measure α) :
∫⁻ a, f a ∂(μ + ν) = ∫⁻ a, f a ∂μ + ∫⁻ a, f a ∂ν := by
simpa [tsum_fintype] using lintegral_sum_measure f fun b => cond b μ ν
#align measure_theory.lintegral_add_measure MeasureTheory.lintegral_add_measure
@[simp]
theorem lintegral_finset_sum_measure {ι} {m : MeasurableSpace α} (s : Finset ι) (f : α → ℝ≥0∞)
(μ : ι → Measure α) : ∫⁻ a, f a ∂(∑ i ∈ s, μ i) = ∑ i ∈ s, ∫⁻ a, f a ∂μ i := by
rw [← Measure.sum_coe_finset, lintegral_sum_measure, ← Finset.tsum_subtype']
simp only [Finset.coe_sort_coe]
#align measure_theory.lintegral_finset_sum_measure MeasureTheory.lintegral_finset_sum_measure
@[simp]
theorem lintegral_zero_measure {m : MeasurableSpace α} (f : α → ℝ≥0∞) :
∫⁻ a, f a ∂(0 : Measure α) = 0 := by
simp [lintegral]
#align measure_theory.lintegral_zero_measure MeasureTheory.lintegral_zero_measure
@[simp]
theorem lintegral_of_isEmpty {α} [MeasurableSpace α] [IsEmpty α] (μ : Measure α) (f : α → ℝ≥0∞) :
∫⁻ x, f x ∂μ = 0 := by
have : Subsingleton (Measure α) := inferInstance
convert lintegral_zero_measure f
theorem set_lintegral_empty (f : α → ℝ≥0∞) : ∫⁻ x in ∅, f x ∂μ = 0 := by
rw [Measure.restrict_empty, lintegral_zero_measure]
#align measure_theory.set_lintegral_empty MeasureTheory.set_lintegral_empty
theorem set_lintegral_univ (f : α → ℝ≥0∞) : ∫⁻ x in univ, f x ∂μ = ∫⁻ x, f x ∂μ := by
rw [Measure.restrict_univ]
#align measure_theory.set_lintegral_univ MeasureTheory.set_lintegral_univ
theorem set_lintegral_measure_zero (s : Set α) (f : α → ℝ≥0∞) (hs' : μ s = 0) :
∫⁻ x in s, f x ∂μ = 0 := by
convert lintegral_zero_measure _
exact Measure.restrict_eq_zero.2 hs'
#align measure_theory.set_lintegral_measure_zero MeasureTheory.set_lintegral_measure_zero
theorem lintegral_finset_sum' (s : Finset β) {f : β → α → ℝ≥0∞}
(hf : ∀ b ∈ s, AEMeasurable (f b) μ) :
∫⁻ a, ∑ b ∈ s, f b a ∂μ = ∑ b ∈ s, ∫⁻ a, f b a ∂μ := by
induction' s using Finset.induction_on with a s has ih
· simp
· simp only [Finset.sum_insert has]
rw [Finset.forall_mem_insert] at hf
rw [lintegral_add_left' hf.1, ih hf.2]
#align measure_theory.lintegral_finset_sum' MeasureTheory.lintegral_finset_sum'
theorem lintegral_finset_sum (s : Finset β) {f : β → α → ℝ≥0∞} (hf : ∀ b ∈ s, Measurable (f b)) :
∫⁻ a, ∑ b ∈ s, f b a ∂μ = ∑ b ∈ s, ∫⁻ a, f b a ∂μ :=
lintegral_finset_sum' s fun b hb => (hf b hb).aemeasurable
#align measure_theory.lintegral_finset_sum MeasureTheory.lintegral_finset_sum
@[simp]
theorem lintegral_const_mul (r : ℝ≥0∞) {f : α → ℝ≥0∞} (hf : Measurable f) :
∫⁻ a, r * f a ∂μ = r * ∫⁻ a, f a ∂μ :=
calc
∫⁻ a, r * f a ∂μ = ∫⁻ a, ⨆ n, (const α r * eapprox f n) a ∂μ := by
congr
funext a
rw [← iSup_eapprox_apply f hf, ENNReal.mul_iSup]
simp
_ = ⨆ n, r * (eapprox f n).lintegral μ := by
rw [lintegral_iSup]
· congr
funext n
rw [← SimpleFunc.const_mul_lintegral, ← SimpleFunc.lintegral_eq_lintegral]
· intro n
exact SimpleFunc.measurable _
· intro i j h a
exact mul_le_mul_left' (monotone_eapprox _ h _) _
_ = r * ∫⁻ a, f a ∂μ := by rw [← ENNReal.mul_iSup, lintegral_eq_iSup_eapprox_lintegral hf]
#align measure_theory.lintegral_const_mul MeasureTheory.lintegral_const_mul
theorem lintegral_const_mul'' (r : ℝ≥0∞) {f : α → ℝ≥0∞} (hf : AEMeasurable f μ) :
∫⁻ a, r * f a ∂μ = r * ∫⁻ a, f a ∂μ := by
have A : ∫⁻ a, f a ∂μ = ∫⁻ a, hf.mk f a ∂μ := lintegral_congr_ae hf.ae_eq_mk
have B : ∫⁻ a, r * f a ∂μ = ∫⁻ a, r * hf.mk f a ∂μ :=
lintegral_congr_ae (EventuallyEq.fun_comp hf.ae_eq_mk _)
rw [A, B, lintegral_const_mul _ hf.measurable_mk]
#align measure_theory.lintegral_const_mul'' MeasureTheory.lintegral_const_mul''
theorem lintegral_const_mul_le (r : ℝ≥0∞) (f : α → ℝ≥0∞) :
r * ∫⁻ a, f a ∂μ ≤ ∫⁻ a, r * f a ∂μ := by
rw [lintegral, ENNReal.mul_iSup]
refine iSup_le fun s => ?_
rw [ENNReal.mul_iSup, iSup_le_iff]
intro hs
rw [← SimpleFunc.const_mul_lintegral, lintegral]
refine le_iSup_of_le (const α r * s) (le_iSup_of_le (fun x => ?_) le_rfl)
exact mul_le_mul_left' (hs x) _
#align measure_theory.lintegral_const_mul_le MeasureTheory.lintegral_const_mul_le
theorem lintegral_const_mul' (r : ℝ≥0∞) (f : α → ℝ≥0∞) (hr : r ≠ ∞) :
∫⁻ a, r * f a ∂μ = r * ∫⁻ a, f a ∂μ := by
by_cases h : r = 0
· simp [h]
apply le_antisymm _ (lintegral_const_mul_le r f)
have rinv : r * r⁻¹ = 1 := ENNReal.mul_inv_cancel h hr
have rinv' : r⁻¹ * r = 1 := by
rw [mul_comm]
exact rinv
have := lintegral_const_mul_le (μ := μ) r⁻¹ fun x => r * f x
simp? [(mul_assoc _ _ _).symm, rinv'] at this says
simp only [(mul_assoc _ _ _).symm, rinv', one_mul] at this
simpa [(mul_assoc _ _ _).symm, rinv] using mul_le_mul_left' this r
#align measure_theory.lintegral_const_mul' MeasureTheory.lintegral_const_mul'
theorem lintegral_mul_const (r : ℝ≥0∞) {f : α → ℝ≥0∞} (hf : Measurable f) :
∫⁻ a, f a * r ∂μ = (∫⁻ a, f a ∂μ) * r := by simp_rw [mul_comm, lintegral_const_mul r hf]
#align measure_theory.lintegral_mul_const MeasureTheory.lintegral_mul_const
theorem lintegral_mul_const'' (r : ℝ≥0∞) {f : α → ℝ≥0∞} (hf : AEMeasurable f μ) :
∫⁻ a, f a * r ∂μ = (∫⁻ a, f a ∂μ) * r := by simp_rw [mul_comm, lintegral_const_mul'' r hf]
#align measure_theory.lintegral_mul_const'' MeasureTheory.lintegral_mul_const''
theorem lintegral_mul_const_le (r : ℝ≥0∞) (f : α → ℝ≥0∞) :
(∫⁻ a, f a ∂μ) * r ≤ ∫⁻ a, f a * r ∂μ := by
simp_rw [mul_comm, lintegral_const_mul_le r f]
#align measure_theory.lintegral_mul_const_le MeasureTheory.lintegral_mul_const_le
theorem lintegral_mul_const' (r : ℝ≥0∞) (f : α → ℝ≥0∞) (hr : r ≠ ∞) :
∫⁻ a, f a * r ∂μ = (∫⁻ a, f a ∂μ) * r := by simp_rw [mul_comm, lintegral_const_mul' r f hr]
#align measure_theory.lintegral_mul_const' MeasureTheory.lintegral_mul_const'
theorem lintegral_lintegral_mul {β} [MeasurableSpace β] {ν : Measure β} {f : α → ℝ≥0∞}
{g : β → ℝ≥0∞} (hf : AEMeasurable f μ) (hg : AEMeasurable g ν) :
∫⁻ x, ∫⁻ y, f x * g y ∂ν ∂μ = (∫⁻ x, f x ∂μ) * ∫⁻ y, g y ∂ν := by
simp [lintegral_const_mul'' _ hg, lintegral_mul_const'' _ hf]
#align measure_theory.lintegral_lintegral_mul MeasureTheory.lintegral_lintegral_mul
-- TODO: Need a better way of rewriting inside of an integral
theorem lintegral_rw₁ {f f' : α → β} (h : f =ᵐ[μ] f') (g : β → ℝ≥0∞) :
∫⁻ a, g (f a) ∂μ = ∫⁻ a, g (f' a) ∂μ :=
lintegral_congr_ae <| h.mono fun a h => by dsimp only; rw [h]
#align measure_theory.lintegral_rw₁ MeasureTheory.lintegral_rw₁
-- TODO: Need a better way of rewriting inside of an integral
theorem lintegral_rw₂ {f₁ f₁' : α → β} {f₂ f₂' : α → γ} (h₁ : f₁ =ᵐ[μ] f₁') (h₂ : f₂ =ᵐ[μ] f₂')
(g : β → γ → ℝ≥0∞) : ∫⁻ a, g (f₁ a) (f₂ a) ∂μ = ∫⁻ a, g (f₁' a) (f₂' a) ∂μ :=
lintegral_congr_ae <| h₁.mp <| h₂.mono fun _ h₂ h₁ => by dsimp only; rw [h₁, h₂]
#align measure_theory.lintegral_rw₂ MeasureTheory.lintegral_rw₂
theorem lintegral_indicator_le (f : α → ℝ≥0∞) (s : Set α) :
∫⁻ a, s.indicator f a ∂μ ≤ ∫⁻ a in s, f a ∂μ := by
simp only [lintegral]
apply iSup_le (fun g ↦ (iSup_le (fun hg ↦ ?_)))
have : g ≤ f := hg.trans (indicator_le_self s f)
refine le_iSup_of_le g (le_iSup_of_le this (le_of_eq ?_))
rw [lintegral_restrict, SimpleFunc.lintegral]
congr with t
by_cases H : t = 0
· simp [H]
congr with x
simp only [mem_preimage, mem_singleton_iff, mem_inter_iff, iff_self_and]
rintro rfl
contrapose! H
simpa [H] using hg x
@[simp]
theorem lintegral_indicator (f : α → ℝ≥0∞) {s : Set α} (hs : MeasurableSet s) :
∫⁻ a, s.indicator f a ∂μ = ∫⁻ a in s, f a ∂μ := by
apply le_antisymm (lintegral_indicator_le f s)
simp only [lintegral, ← restrict_lintegral_eq_lintegral_restrict _ hs, iSup_subtype']
refine iSup_mono' (Subtype.forall.2 fun φ hφ => ?_)
refine ⟨⟨φ.restrict s, fun x => ?_⟩, le_rfl⟩
simp [hφ x, hs, indicator_le_indicator]
#align measure_theory.lintegral_indicator MeasureTheory.lintegral_indicator
theorem lintegral_indicator₀ (f : α → ℝ≥0∞) {s : Set α} (hs : NullMeasurableSet s μ) :
∫⁻ a, s.indicator f a ∂μ = ∫⁻ a in s, f a ∂μ := by
rw [← lintegral_congr_ae (indicator_ae_eq_of_ae_eq_set hs.toMeasurable_ae_eq),
lintegral_indicator _ (measurableSet_toMeasurable _ _),
Measure.restrict_congr_set hs.toMeasurable_ae_eq]
#align measure_theory.lintegral_indicator₀ MeasureTheory.lintegral_indicator₀
theorem lintegral_indicator_const_le (s : Set α) (c : ℝ≥0∞) :
∫⁻ a, s.indicator (fun _ => c) a ∂μ ≤ c * μ s :=
(lintegral_indicator_le _ _).trans (set_lintegral_const s c).le
theorem lintegral_indicator_const₀ {s : Set α} (hs : NullMeasurableSet s μ) (c : ℝ≥0∞) :
∫⁻ a, s.indicator (fun _ => c) a ∂μ = c * μ s := by
rw [lintegral_indicator₀ _ hs, set_lintegral_const]
theorem lintegral_indicator_const {s : Set α} (hs : MeasurableSet s) (c : ℝ≥0∞) :
∫⁻ a, s.indicator (fun _ => c) a ∂μ = c * μ s :=
lintegral_indicator_const₀ hs.nullMeasurableSet c
#align measure_theory.lintegral_indicator_const MeasureTheory.lintegral_indicator_const
theorem set_lintegral_eq_const {f : α → ℝ≥0∞} (hf : Measurable f) (r : ℝ≥0∞) :
∫⁻ x in { x | f x = r }, f x ∂μ = r * μ { x | f x = r } := by
have : ∀ᵐ x ∂μ, x ∈ { x | f x = r } → f x = r := ae_of_all μ fun _ hx => hx
rw [set_lintegral_congr_fun _ this]
· rw [lintegral_const, Measure.restrict_apply MeasurableSet.univ, Set.univ_inter]
· exact hf (measurableSet_singleton r)
#align measure_theory.set_lintegral_eq_const MeasureTheory.set_lintegral_eq_const
theorem lintegral_indicator_one_le (s : Set α) : ∫⁻ a, s.indicator 1 a ∂μ ≤ μ s :=
(lintegral_indicator_const_le _ _).trans <| (one_mul _).le
@[simp]
theorem lintegral_indicator_one₀ (hs : NullMeasurableSet s μ) : ∫⁻ a, s.indicator 1 a ∂μ = μ s :=
(lintegral_indicator_const₀ hs _).trans <| one_mul _
@[simp]
theorem lintegral_indicator_one (hs : MeasurableSet s) : ∫⁻ a, s.indicator 1 a ∂μ = μ s :=
(lintegral_indicator_const hs _).trans <| one_mul _
#align measure_theory.lintegral_indicator_one MeasureTheory.lintegral_indicator_one
theorem lintegral_add_mul_meas_add_le_le_lintegral {f g : α → ℝ≥0∞} (hle : f ≤ᵐ[μ] g)
(hg : AEMeasurable g μ) (ε : ℝ≥0∞) :
∫⁻ a, f a ∂μ + ε * μ { x | f x + ε ≤ g x } ≤ ∫⁻ a, g a ∂μ := by
rcases exists_measurable_le_lintegral_eq μ f with ⟨φ, hφm, hφ_le, hφ_eq⟩
calc
∫⁻ x, f x ∂μ + ε * μ { x | f x + ε ≤ g x } = ∫⁻ x, φ x ∂μ + ε * μ { x | f x + ε ≤ g x } := by
rw [hφ_eq]
_ ≤ ∫⁻ x, φ x ∂μ + ε * μ { x | φ x + ε ≤ g x } := by
gcongr
exact fun x => (add_le_add_right (hφ_le _) _).trans
_ = ∫⁻ x, φ x + indicator { x | φ x + ε ≤ g x } (fun _ => ε) x ∂μ := by
rw [lintegral_add_left hφm, lintegral_indicator₀, set_lintegral_const]
exact measurableSet_le (hφm.nullMeasurable.measurable'.add_const _) hg.nullMeasurable
_ ≤ ∫⁻ x, g x ∂μ := lintegral_mono_ae (hle.mono fun x hx₁ => ?_)
simp only [indicator_apply]; split_ifs with hx₂
exacts [hx₂, (add_zero _).trans_le <| (hφ_le x).trans hx₁]
#align measure_theory.lintegral_add_mul_meas_add_le_le_lintegral MeasureTheory.lintegral_add_mul_meas_add_le_le_lintegral
theorem mul_meas_ge_le_lintegral₀ {f : α → ℝ≥0∞} (hf : AEMeasurable f μ) (ε : ℝ≥0∞) :
ε * μ { x | ε ≤ f x } ≤ ∫⁻ a, f a ∂μ := by
simpa only [lintegral_zero, zero_add] using
lintegral_add_mul_meas_add_le_le_lintegral (ae_of_all _ fun x => zero_le (f x)) hf ε
#align measure_theory.mul_meas_ge_le_lintegral₀ MeasureTheory.mul_meas_ge_le_lintegral₀
theorem mul_meas_ge_le_lintegral {f : α → ℝ≥0∞} (hf : Measurable f) (ε : ℝ≥0∞) :
ε * μ { x | ε ≤ f x } ≤ ∫⁻ a, f a ∂μ :=
mul_meas_ge_le_lintegral₀ hf.aemeasurable ε
#align measure_theory.mul_meas_ge_le_lintegral MeasureTheory.mul_meas_ge_le_lintegral
lemma meas_le_lintegral₀ {f : α → ℝ≥0∞} (hf : AEMeasurable f μ)
{s : Set α} (hs : ∀ x ∈ s, 1 ≤ f x) : μ s ≤ ∫⁻ a, f a ∂μ := by
apply le_trans _ (mul_meas_ge_le_lintegral₀ hf 1)
rw [one_mul]
exact measure_mono hs
lemma lintegral_le_meas {s : Set α} {f : α → ℝ≥0∞} (hf : ∀ a, f a ≤ 1) (h'f : ∀ a ∈ sᶜ, f a = 0) :
∫⁻ a, f a ∂μ ≤ μ s := by
apply (lintegral_mono (fun x ↦ ?_)).trans (lintegral_indicator_one_le s)
by_cases hx : x ∈ s
· simpa [hx] using hf x
· simpa [hx] using h'f x hx
theorem lintegral_eq_top_of_measure_eq_top_ne_zero {f : α → ℝ≥0∞} (hf : AEMeasurable f μ)
(hμf : μ {x | f x = ∞} ≠ 0) : ∫⁻ x, f x ∂μ = ∞ :=
eq_top_iff.mpr <|
calc
∞ = ∞ * μ { x | ∞ ≤ f x } := by simp [mul_eq_top, hμf]
_ ≤ ∫⁻ x, f x ∂μ := mul_meas_ge_le_lintegral₀ hf ∞
#align measure_theory.lintegral_eq_top_of_measure_eq_top_ne_zero MeasureTheory.lintegral_eq_top_of_measure_eq_top_ne_zero
theorem setLintegral_eq_top_of_measure_eq_top_ne_zero (hf : AEMeasurable f (μ.restrict s))
(hμf : μ ({x ∈ s | f x = ∞}) ≠ 0) : ∫⁻ x in s, f x ∂μ = ∞ :=
lintegral_eq_top_of_measure_eq_top_ne_zero hf <|
mt (eq_bot_mono <| by rw [← setOf_inter_eq_sep]; exact Measure.le_restrict_apply _ _) hμf
#align measure_theory.set_lintegral_eq_top_of_measure_eq_top_ne_zero MeasureTheory.setLintegral_eq_top_of_measure_eq_top_ne_zero
theorem measure_eq_top_of_lintegral_ne_top (hf : AEMeasurable f μ) (hμf : ∫⁻ x, f x ∂μ ≠ ∞) :
μ {x | f x = ∞} = 0 :=
of_not_not fun h => hμf <| lintegral_eq_top_of_measure_eq_top_ne_zero hf h
#align measure_theory.measure_eq_top_of_lintegral_ne_top MeasureTheory.measure_eq_top_of_lintegral_ne_top
theorem measure_eq_top_of_setLintegral_ne_top (hf : AEMeasurable f (μ.restrict s))
(hμf : ∫⁻ x in s, f x ∂μ ≠ ∞) : μ ({x ∈ s | f x = ∞}) = 0 :=
of_not_not fun h => hμf <| setLintegral_eq_top_of_measure_eq_top_ne_zero hf h
#align measure_theory.measure_eq_top_of_set_lintegral_ne_top MeasureTheory.measure_eq_top_of_setLintegral_ne_top
theorem meas_ge_le_lintegral_div {f : α → ℝ≥0∞} (hf : AEMeasurable f μ) {ε : ℝ≥0∞} (hε : ε ≠ 0)
(hε' : ε ≠ ∞) : μ { x | ε ≤ f x } ≤ (∫⁻ a, f a ∂μ) / ε :=
(ENNReal.le_div_iff_mul_le (Or.inl hε) (Or.inl hε')).2 <| by
rw [mul_comm]
exact mul_meas_ge_le_lintegral₀ hf ε
#align measure_theory.meas_ge_le_lintegral_div MeasureTheory.meas_ge_le_lintegral_div
| Mathlib/MeasureTheory/Integral/Lebesgue.lean | 905 | 918 | theorem ae_eq_of_ae_le_of_lintegral_le {f g : α → ℝ≥0∞} (hfg : f ≤ᵐ[μ] g) (hf : ∫⁻ x, f x ∂μ ≠ ∞)
(hg : AEMeasurable g μ) (hgf : ∫⁻ x, g x ∂μ ≤ ∫⁻ x, f x ∂μ) : f =ᵐ[μ] g := by |
have : ∀ n : ℕ, ∀ᵐ x ∂μ, g x < f x + (n : ℝ≥0∞)⁻¹ := by
intro n
simp only [ae_iff, not_lt]
have : ∫⁻ x, f x ∂μ + (↑n)⁻¹ * μ { x : α | f x + (n : ℝ≥0∞)⁻¹ ≤ g x } ≤ ∫⁻ x, f x ∂μ :=
(lintegral_add_mul_meas_add_le_le_lintegral hfg hg n⁻¹).trans hgf
rw [(ENNReal.cancel_of_ne hf).add_le_iff_nonpos_right, nonpos_iff_eq_zero, mul_eq_zero] at this
exact this.resolve_left (ENNReal.inv_ne_zero.2 (ENNReal.natCast_ne_top _))
refine hfg.mp ((ae_all_iff.2 this).mono fun x hlt hle => hle.antisymm ?_)
suffices Tendsto (fun n : ℕ => f x + (n : ℝ≥0∞)⁻¹) atTop (𝓝 (f x)) from
ge_of_tendsto' this fun i => (hlt i).le
simpa only [inv_top, add_zero] using
tendsto_const_nhds.add (ENNReal.tendsto_inv_iff.2 ENNReal.tendsto_nat_nhds_top)
|
import Mathlib.MeasureTheory.Measure.Restrict
open scoped ENNReal NNReal Topology
open Set MeasureTheory Measure Filter Function MeasurableSpace ENNReal
variable {α β δ ι : Type*}
namespace MeasureTheory
variable {m0 : MeasurableSpace α} [MeasurableSpace β] {μ ν ν₁ ν₂: Measure α}
{s t : Set α}
section IsFiniteMeasure
class IsFiniteMeasure (μ : Measure α) : Prop where
measure_univ_lt_top : μ univ < ∞
#align measure_theory.is_finite_measure MeasureTheory.IsFiniteMeasure
#align measure_theory.is_finite_measure.measure_univ_lt_top MeasureTheory.IsFiniteMeasure.measure_univ_lt_top
theorem not_isFiniteMeasure_iff : ¬IsFiniteMeasure μ ↔ μ Set.univ = ∞ := by
refine ⟨fun h => ?_, fun h => fun h' => h'.measure_univ_lt_top.ne h⟩
by_contra h'
exact h ⟨lt_top_iff_ne_top.mpr h'⟩
#align measure_theory.not_is_finite_measure_iff MeasureTheory.not_isFiniteMeasure_iff
instance Restrict.isFiniteMeasure (μ : Measure α) [hs : Fact (μ s < ∞)] :
IsFiniteMeasure (μ.restrict s) :=
⟨by simpa using hs.elim⟩
#align measure_theory.restrict.is_finite_measure MeasureTheory.Restrict.isFiniteMeasure
theorem measure_lt_top (μ : Measure α) [IsFiniteMeasure μ] (s : Set α) : μ s < ∞ :=
(measure_mono (subset_univ s)).trans_lt IsFiniteMeasure.measure_univ_lt_top
#align measure_theory.measure_lt_top MeasureTheory.measure_lt_top
instance isFiniteMeasureRestrict (μ : Measure α) (s : Set α) [h : IsFiniteMeasure μ] :
IsFiniteMeasure (μ.restrict s) :=
⟨by simpa using measure_lt_top μ s⟩
#align measure_theory.is_finite_measure_restrict MeasureTheory.isFiniteMeasureRestrict
theorem measure_ne_top (μ : Measure α) [IsFiniteMeasure μ] (s : Set α) : μ s ≠ ∞ :=
ne_of_lt (measure_lt_top μ s)
#align measure_theory.measure_ne_top MeasureTheory.measure_ne_top
| Mathlib/MeasureTheory/Measure/Typeclasses.lean | 65 | 72 | theorem measure_compl_le_add_of_le_add [IsFiniteMeasure μ] (hs : MeasurableSet s)
(ht : MeasurableSet t) {ε : ℝ≥0∞} (h : μ s ≤ μ t + ε) : μ tᶜ ≤ μ sᶜ + ε := by |
rw [measure_compl ht (measure_ne_top μ _), measure_compl hs (measure_ne_top μ _),
tsub_le_iff_right]
calc
μ univ = μ univ - μ s + μ s := (tsub_add_cancel_of_le <| measure_mono s.subset_univ).symm
_ ≤ μ univ - μ s + (μ t + ε) := add_le_add_left h _
_ = _ := by rw [add_right_comm, add_assoc]
|
import Mathlib.Algebra.Associated
import Mathlib.Algebra.GeomSum
import Mathlib.Algebra.GroupWithZero.NonZeroDivisors
import Mathlib.Algebra.Module.Defs
import Mathlib.Algebra.SMulWithZero
import Mathlib.Data.Nat.Choose.Sum
import Mathlib.Data.Nat.Lattice
import Mathlib.RingTheory.Nilpotent.Defs
#align_import ring_theory.nilpotent from "leanprover-community/mathlib"@"da420a8c6dd5bdfb85c4ced85c34388f633bc6ff"
universe u v
open Function Set
variable {R S : Type*} {x y : R}
theorem IsNilpotent.neg [Ring R] (h : IsNilpotent x) : IsNilpotent (-x) := by
obtain ⟨n, hn⟩ := h
use n
rw [neg_pow, hn, mul_zero]
#align is_nilpotent.neg IsNilpotent.neg
@[simp]
theorem isNilpotent_neg_iff [Ring R] : IsNilpotent (-x) ↔ IsNilpotent x :=
⟨fun h => neg_neg x ▸ h.neg, fun h => h.neg⟩
#align is_nilpotent_neg_iff isNilpotent_neg_iff
lemma IsNilpotent.smul [MonoidWithZero R] [MonoidWithZero S] [MulActionWithZero R S]
[SMulCommClass R S S] [IsScalarTower R S S] {a : S} (ha : IsNilpotent a) (t : R) :
IsNilpotent (t • a) := by
obtain ⟨k, ha⟩ := ha
use k
rw [smul_pow, ha, smul_zero]
theorem IsNilpotent.isUnit_sub_one [Ring R] {r : R} (hnil : IsNilpotent r) : IsUnit (r - 1) := by
obtain ⟨n, hn⟩ := hnil
refine ⟨⟨r - 1, -∑ i ∈ Finset.range n, r ^ i, ?_, ?_⟩, rfl⟩
· simp [mul_geom_sum, hn]
· simp [geom_sum_mul, hn]
theorem IsNilpotent.isUnit_one_sub [Ring R] {r : R} (hnil : IsNilpotent r) : IsUnit (1 - r) := by
rw [← IsUnit.neg_iff, neg_sub]
exact isUnit_sub_one hnil
theorem IsNilpotent.isUnit_add_one [Ring R] {r : R} (hnil : IsNilpotent r) : IsUnit (r + 1) := by
rw [← IsUnit.neg_iff, neg_add']
exact isUnit_sub_one hnil.neg
theorem IsNilpotent.isUnit_one_add [Ring R] {r : R} (hnil : IsNilpotent r) : IsUnit (1 + r) :=
add_comm r 1 ▸ isUnit_add_one hnil
theorem IsNilpotent.isUnit_add_left_of_commute [Ring R] {r u : R}
(hnil : IsNilpotent r) (hu : IsUnit u) (h_comm : Commute r u) :
IsUnit (u + r) := by
rw [← Units.isUnit_mul_units _ hu.unit⁻¹, add_mul, IsUnit.mul_val_inv]
replace h_comm : Commute r (↑hu.unit⁻¹) := Commute.units_inv_right h_comm
refine IsNilpotent.isUnit_one_add ?_
exact (hu.unit⁻¹.isUnit.isNilpotent_mul_unit_of_commute_iff h_comm).mpr hnil
theorem IsNilpotent.isUnit_add_right_of_commute [Ring R] {r u : R}
(hnil : IsNilpotent r) (hu : IsUnit u) (h_comm : Commute r u) :
IsUnit (r + u) :=
add_comm r u ▸ hnil.isUnit_add_left_of_commute hu h_comm
instance [Zero R] [Pow R ℕ] [Zero S] [Pow S ℕ] [IsReduced R] [IsReduced S] : IsReduced (R × S) where
eq_zero _ := fun ⟨n, hn⟩ ↦ have hn := Prod.ext_iff.1 hn
Prod.ext (IsReduced.eq_zero _ ⟨n, hn.1⟩) (IsReduced.eq_zero _ ⟨n, hn.2⟩)
theorem Prime.isRadical [CommMonoidWithZero R] {y : R} (hy : Prime y) : IsRadical y :=
fun _ _ ↦ hy.dvd_of_dvd_pow
theorem zero_isRadical_iff [MonoidWithZero R] : IsRadical (0 : R) ↔ IsReduced R := by
simp_rw [isReduced_iff, IsNilpotent, exists_imp, ← zero_dvd_iff]
exact forall_swap
#align zero_is_radical_iff zero_isRadical_iff
| Mathlib/RingTheory/Nilpotent/Basic.lean | 100 | 102 | theorem isReduced_iff_pow_one_lt [MonoidWithZero R] (k : ℕ) (hk : 1 < k) :
IsReduced R ↔ ∀ x : R, x ^ k = 0 → x = 0 := by |
simp_rw [← zero_isRadical_iff, isRadical_iff_pow_one_lt k hk, zero_dvd_iff]
|
import Mathlib.Algebra.Module.Torsion
import Mathlib.RingTheory.DedekindDomain.Ideal
#align_import algebra.module.dedekind_domain from "leanprover-community/mathlib"@"cdc34484a07418af43daf8198beaf5c00324bca8"
universe u v
variable {R : Type u} [CommRing R] [IsDomain R] {M : Type v} [AddCommGroup M] [Module R M]
open scoped DirectSum
namespace Submodule
variable [IsDedekindDomain R]
open UniqueFactorizationMonoid
open scoped Classical
| Mathlib/Algebra/Module/DedekindDomain.lean | 37 | 59 | theorem isInternal_prime_power_torsion_of_is_torsion_by_ideal {I : Ideal R} (hI : I ≠ ⊥)
(hM : Module.IsTorsionBySet R M I) :
DirectSum.IsInternal fun p : (factors I).toFinset =>
torsionBySet R M (p ^ (factors I).count ↑p : Ideal R) := by |
let P := factors I
have prime_of_mem := fun p (hp : p ∈ P.toFinset) =>
prime_of_factor p (Multiset.mem_toFinset.mp hp)
apply torsionBySet_isInternal (p := fun p => p ^ P.count p) _
· convert hM
rw [← Finset.inf_eq_iInf, IsDedekindDomain.inf_prime_pow_eq_prod, ← Finset.prod_multiset_count,
← associated_iff_eq]
· exact factors_prod hI
· exact prime_of_mem
· exact fun _ _ _ _ ij => ij
· intro p hp q hq pq; dsimp
rw [irreducible_pow_sup]
· suffices (normalizedFactors _).count p = 0 by rw [this, zero_min, pow_zero, Ideal.one_eq_top]
rw [Multiset.count_eq_zero,
normalizedFactors_of_irreducible_pow (prime_of_mem q hq).irreducible,
Multiset.mem_replicate]
exact fun H => pq <| H.2.trans <| normalize_eq q
· rw [← Ideal.zero_eq_bot]; apply pow_ne_zero; exact (prime_of_mem q hq).ne_zero
· exact (prime_of_mem p hp).irreducible
|
import Mathlib.Topology.Order.LeftRightNhds
open Set Filter TopologicalSpace Topology Function
open OrderDual (toDual ofDual)
variable {α β γ : Type*}
section OrderTopology
variable [TopologicalSpace α] [TopologicalSpace β] [LinearOrder α] [LinearOrder β] [OrderTopology α]
[OrderTopology β]
theorem IsLUB.frequently_mem {a : α} {s : Set α} (ha : IsLUB s a) (hs : s.Nonempty) :
∃ᶠ x in 𝓝[≤] a, x ∈ s := by
rcases hs with ⟨a', ha'⟩
intro h
rcases (ha.1 ha').eq_or_lt with (rfl | ha'a)
· exact h.self_of_nhdsWithin le_rfl ha'
· rcases (mem_nhdsWithin_Iic_iff_exists_Ioc_subset' ha'a).1 h with ⟨b, hba, hb⟩
rcases ha.exists_between hba with ⟨b', hb's, hb'⟩
exact hb hb' hb's
#align is_lub.frequently_mem IsLUB.frequently_mem
theorem IsLUB.frequently_nhds_mem {a : α} {s : Set α} (ha : IsLUB s a) (hs : s.Nonempty) :
∃ᶠ x in 𝓝 a, x ∈ s :=
(ha.frequently_mem hs).filter_mono inf_le_left
#align is_lub.frequently_nhds_mem IsLUB.frequently_nhds_mem
theorem IsGLB.frequently_mem {a : α} {s : Set α} (ha : IsGLB s a) (hs : s.Nonempty) :
∃ᶠ x in 𝓝[≥] a, x ∈ s :=
IsLUB.frequently_mem (α := αᵒᵈ) ha hs
#align is_glb.frequently_mem IsGLB.frequently_mem
theorem IsGLB.frequently_nhds_mem {a : α} {s : Set α} (ha : IsGLB s a) (hs : s.Nonempty) :
∃ᶠ x in 𝓝 a, x ∈ s :=
(ha.frequently_mem hs).filter_mono inf_le_left
#align is_glb.frequently_nhds_mem IsGLB.frequently_nhds_mem
theorem IsLUB.mem_closure {a : α} {s : Set α} (ha : IsLUB s a) (hs : s.Nonempty) : a ∈ closure s :=
(ha.frequently_nhds_mem hs).mem_closure
#align is_lub.mem_closure IsLUB.mem_closure
theorem IsGLB.mem_closure {a : α} {s : Set α} (ha : IsGLB s a) (hs : s.Nonempty) : a ∈ closure s :=
(ha.frequently_nhds_mem hs).mem_closure
#align is_glb.mem_closure IsGLB.mem_closure
theorem IsLUB.nhdsWithin_neBot {a : α} {s : Set α} (ha : IsLUB s a) (hs : s.Nonempty) :
NeBot (𝓝[s] a) :=
mem_closure_iff_nhdsWithin_neBot.1 (ha.mem_closure hs)
#align is_lub.nhds_within_ne_bot IsLUB.nhdsWithin_neBot
theorem IsGLB.nhdsWithin_neBot : ∀ {a : α} {s : Set α}, IsGLB s a → s.Nonempty → NeBot (𝓝[s] a) :=
IsLUB.nhdsWithin_neBot (α := αᵒᵈ)
#align is_glb.nhds_within_ne_bot IsGLB.nhdsWithin_neBot
theorem isLUB_of_mem_nhds {s : Set α} {a : α} {f : Filter α} (hsa : a ∈ upperBounds s) (hsf : s ∈ f)
[NeBot (f ⊓ 𝓝 a)] : IsLUB s a :=
⟨hsa, fun b hb =>
not_lt.1 fun hba =>
have : s ∩ { a | b < a } ∈ f ⊓ 𝓝 a := inter_mem_inf hsf (IsOpen.mem_nhds (isOpen_lt' _) hba)
let ⟨_x, ⟨hxs, hxb⟩⟩ := Filter.nonempty_of_mem this
have : b < b := lt_of_lt_of_le hxb <| hb hxs
lt_irrefl b this⟩
#align is_lub_of_mem_nhds isLUB_of_mem_nhds
theorem isLUB_of_mem_closure {s : Set α} {a : α} (hsa : a ∈ upperBounds s) (hsf : a ∈ closure s) :
IsLUB s a := by
rw [mem_closure_iff_clusterPt, ClusterPt, inf_comm] at hsf
exact isLUB_of_mem_nhds hsa (mem_principal_self s)
#align is_lub_of_mem_closure isLUB_of_mem_closure
theorem isGLB_of_mem_nhds :
∀ {s : Set α} {a : α} {f : Filter α}, a ∈ lowerBounds s → s ∈ f → NeBot (f ⊓ 𝓝 a) → IsGLB s a :=
isLUB_of_mem_nhds (α := αᵒᵈ)
#align is_glb_of_mem_nhds isGLB_of_mem_nhds
theorem isGLB_of_mem_closure {s : Set α} {a : α} (hsa : a ∈ lowerBounds s) (hsf : a ∈ closure s) :
IsGLB s a :=
isLUB_of_mem_closure (α := αᵒᵈ) hsa hsf
#align is_glb_of_mem_closure isGLB_of_mem_closure
theorem IsLUB.mem_upperBounds_of_tendsto [Preorder γ] [TopologicalSpace γ] [OrderClosedTopology γ]
{f : α → γ} {s : Set α} {a : α} {b : γ} (hf : MonotoneOn f s) (ha : IsLUB s a)
(hb : Tendsto f (𝓝[s] a) (𝓝 b)) : b ∈ upperBounds (f '' s) := by
rintro _ ⟨x, hx, rfl⟩
replace ha := ha.inter_Ici_of_mem hx
haveI := ha.nhdsWithin_neBot ⟨x, hx, le_rfl⟩
refine ge_of_tendsto (hb.mono_left (nhdsWithin_mono a (inter_subset_left (t := Ici x)))) ?_
exact mem_of_superset self_mem_nhdsWithin fun y hy => hf hx hy.1 hy.2
#align is_lub.mem_upper_bounds_of_tendsto IsLUB.mem_upperBounds_of_tendsto
-- For a version of this theorem in which the convergence considered on the domain `α` is as `x : α`
-- tends to infinity, rather than tending to a point `x` in `α`, see `isLUB_of_tendsto_atTop`
theorem IsLUB.isLUB_of_tendsto [Preorder γ] [TopologicalSpace γ] [OrderClosedTopology γ] {f : α → γ}
{s : Set α} {a : α} {b : γ} (hf : MonotoneOn f s) (ha : IsLUB s a) (hs : s.Nonempty)
(hb : Tendsto f (𝓝[s] a) (𝓝 b)) : IsLUB (f '' s) b :=
haveI := ha.nhdsWithin_neBot hs
⟨ha.mem_upperBounds_of_tendsto hf hb, fun _b' hb' =>
le_of_tendsto hb (mem_of_superset self_mem_nhdsWithin fun _ hx => hb' <| mem_image_of_mem _ hx)⟩
#align is_lub.is_lub_of_tendsto IsLUB.isLUB_of_tendsto
theorem IsGLB.mem_lowerBounds_of_tendsto [Preorder γ] [TopologicalSpace γ] [OrderClosedTopology γ]
{f : α → γ} {s : Set α} {a : α} {b : γ} (hf : MonotoneOn f s) (ha : IsGLB s a)
(hb : Tendsto f (𝓝[s] a) (𝓝 b)) : b ∈ lowerBounds (f '' s) :=
IsLUB.mem_upperBounds_of_tendsto (α := αᵒᵈ) (γ := γᵒᵈ) hf.dual ha hb
#align is_glb.mem_lower_bounds_of_tendsto IsGLB.mem_lowerBounds_of_tendsto
-- For a version of this theorem in which the convergence considered on the domain `α` is as
-- `x : α` tends to negative infinity, rather than tending to a point `x` in `α`, see
-- `isGLB_of_tendsto_atBot`
theorem IsGLB.isGLB_of_tendsto [Preorder γ] [TopologicalSpace γ] [OrderClosedTopology γ] {f : α → γ}
{s : Set α} {a : α} {b : γ} (hf : MonotoneOn f s) :
IsGLB s a → s.Nonempty → Tendsto f (𝓝[s] a) (𝓝 b) → IsGLB (f '' s) b :=
IsLUB.isLUB_of_tendsto (α := αᵒᵈ) (γ := γᵒᵈ) hf.dual
#align is_glb.is_glb_of_tendsto IsGLB.isGLB_of_tendsto
theorem IsLUB.mem_lowerBounds_of_tendsto [Preorder γ] [TopologicalSpace γ] [OrderClosedTopology γ]
{f : α → γ} {s : Set α} {a : α} {b : γ} (hf : AntitoneOn f s) (ha : IsLUB s a)
(hb : Tendsto f (𝓝[s] a) (𝓝 b)) : b ∈ lowerBounds (f '' s) :=
IsLUB.mem_upperBounds_of_tendsto (γ := γᵒᵈ) hf ha hb
#align is_lub.mem_lower_bounds_of_tendsto IsLUB.mem_lowerBounds_of_tendsto
theorem IsLUB.isGLB_of_tendsto [Preorder γ] [TopologicalSpace γ] [OrderClosedTopology γ] :
∀ {f : α → γ} {s : Set α} {a : α} {b : γ},
AntitoneOn f s → IsLUB s a → s.Nonempty → Tendsto f (𝓝[s] a) (𝓝 b) → IsGLB (f '' s) b :=
IsLUB.isLUB_of_tendsto (γ := γᵒᵈ)
#align is_lub.is_glb_of_tendsto IsLUB.isGLB_of_tendsto
theorem IsGLB.mem_upperBounds_of_tendsto [Preorder γ] [TopologicalSpace γ] [OrderClosedTopology γ]
{f : α → γ} {s : Set α} {a : α} {b : γ} (hf : AntitoneOn f s) (ha : IsGLB s a)
(hb : Tendsto f (𝓝[s] a) (𝓝 b)) : b ∈ upperBounds (f '' s) :=
IsGLB.mem_lowerBounds_of_tendsto (γ := γᵒᵈ) hf ha hb
#align is_glb.mem_upper_bounds_of_tendsto IsGLB.mem_upperBounds_of_tendsto
theorem IsGLB.isLUB_of_tendsto [Preorder γ] [TopologicalSpace γ] [OrderClosedTopology γ] :
∀ {f : α → γ} {s : Set α} {a : α} {b : γ},
AntitoneOn f s → IsGLB s a → s.Nonempty → Tendsto f (𝓝[s] a) (𝓝 b) → IsLUB (f '' s) b :=
IsGLB.isGLB_of_tendsto (γ := γᵒᵈ)
#align is_glb.is_lub_of_tendsto IsGLB.isLUB_of_tendsto
theorem IsLUB.mem_of_isClosed {a : α} {s : Set α} (ha : IsLUB s a) (hs : s.Nonempty)
(sc : IsClosed s) : a ∈ s :=
sc.closure_subset <| ha.mem_closure hs
#align is_lub.mem_of_is_closed IsLUB.mem_of_isClosed
alias IsClosed.isLUB_mem := IsLUB.mem_of_isClosed
#align is_closed.is_lub_mem IsClosed.isLUB_mem
theorem IsGLB.mem_of_isClosed {a : α} {s : Set α} (ha : IsGLB s a) (hs : s.Nonempty)
(sc : IsClosed s) : a ∈ s :=
sc.closure_subset <| ha.mem_closure hs
#align is_glb.mem_of_is_closed IsGLB.mem_of_isClosed
alias IsClosed.isGLB_mem := IsGLB.mem_of_isClosed
#align is_closed.is_glb_mem IsClosed.isGLB_mem
theorem IsLUB.exists_seq_strictMono_tendsto_of_not_mem {t : Set α} {x : α}
[IsCountablyGenerated (𝓝 x)] (htx : IsLUB t x) (not_mem : x ∉ t) (ht : t.Nonempty) :
∃ u : ℕ → α, StrictMono u ∧ (∀ n, u n < x) ∧ Tendsto u atTop (𝓝 x) ∧ ∀ n, u n ∈ t := by
obtain ⟨v, hvx, hvt⟩ := exists_seq_forall_of_frequently (htx.frequently_mem ht)
replace hvx := hvx.mono_right nhdsWithin_le_nhds
have hvx' : ∀ {n}, v n < x := (htx.1 (hvt _)).lt_of_ne (ne_of_mem_of_not_mem (hvt _) not_mem)
have : ∀ k, ∀ᶠ l in atTop, v k < v l := fun k => hvx.eventually (lt_mem_nhds hvx')
choose N hN hvN using fun k => ((eventually_gt_atTop k).and (this k)).exists
refine ⟨fun k => v (N^[k] 0), strictMono_nat_of_lt_succ fun _ => ?_, fun _ => hvx',
hvx.comp (strictMono_nat_of_lt_succ fun _ => ?_).tendsto_atTop, fun _ => hvt _⟩
· rw [iterate_succ_apply']; exact hvN _
· rw [iterate_succ_apply']; exact hN _
#align is_lub.exists_seq_strict_mono_tendsto_of_not_mem IsLUB.exists_seq_strictMono_tendsto_of_not_mem
theorem IsLUB.exists_seq_monotone_tendsto {t : Set α} {x : α} [IsCountablyGenerated (𝓝 x)]
(htx : IsLUB t x) (ht : t.Nonempty) :
∃ u : ℕ → α, Monotone u ∧ (∀ n, u n ≤ x) ∧ Tendsto u atTop (𝓝 x) ∧ ∀ n, u n ∈ t := by
by_cases h : x ∈ t
· exact ⟨fun _ => x, monotone_const, fun n => le_rfl, tendsto_const_nhds, fun _ => h⟩
· rcases htx.exists_seq_strictMono_tendsto_of_not_mem h ht with ⟨u, hu⟩
exact ⟨u, hu.1.monotone, fun n => (hu.2.1 n).le, hu.2.2⟩
#align is_lub.exists_seq_monotone_tendsto IsLUB.exists_seq_monotone_tendsto
theorem exists_seq_strictMono_tendsto' {α : Type*} [LinearOrder α] [TopologicalSpace α]
[DenselyOrdered α] [OrderTopology α] [FirstCountableTopology α] {x y : α} (hy : y < x) :
∃ u : ℕ → α, StrictMono u ∧ (∀ n, u n ∈ Ioo y x) ∧ Tendsto u atTop (𝓝 x) := by
have hx : x ∉ Ioo y x := fun h => (lt_irrefl x h.2).elim
have ht : Set.Nonempty (Ioo y x) := nonempty_Ioo.2 hy
rcases (isLUB_Ioo hy).exists_seq_strictMono_tendsto_of_not_mem hx ht with ⟨u, hu⟩
exact ⟨u, hu.1, hu.2.2.symm⟩
#align exists_seq_strict_mono_tendsto' exists_seq_strictMono_tendsto'
| Mathlib/Topology/Order/IsLUB.lean | 204 | 208 | theorem exists_seq_strictMono_tendsto [DenselyOrdered α] [NoMinOrder α] [FirstCountableTopology α]
(x : α) : ∃ u : ℕ → α, StrictMono u ∧ (∀ n, u n < x) ∧ Tendsto u atTop (𝓝 x) := by |
obtain ⟨y, hy⟩ : ∃ y, y < x := exists_lt x
rcases exists_seq_strictMono_tendsto' hy with ⟨u, hu_mono, hu_mem, hux⟩
exact ⟨u, hu_mono, fun n => (hu_mem n).2, hux⟩
|
import Mathlib.Algebra.IsPrimePow
import Mathlib.NumberTheory.ArithmeticFunction
import Mathlib.Analysis.SpecialFunctions.Log.Basic
#align_import number_theory.von_mangoldt from "leanprover-community/mathlib"@"c946d6097a6925ad16d7ec55677bbc977f9846de"
namespace ArithmeticFunction
open Finset Nat
open scoped ArithmeticFunction
noncomputable def log : ArithmeticFunction ℝ :=
⟨fun n => Real.log n, by simp⟩
#align nat.arithmetic_function.log ArithmeticFunction.log
@[simp]
theorem log_apply {n : ℕ} : log n = Real.log n :=
rfl
#align nat.arithmetic_function.log_apply ArithmeticFunction.log_apply
noncomputable def vonMangoldt : ArithmeticFunction ℝ :=
⟨fun n => if IsPrimePow n then Real.log (minFac n) else 0, if_neg not_isPrimePow_zero⟩
#align nat.arithmetic_function.von_mangoldt ArithmeticFunction.vonMangoldt
@[inherit_doc] scoped[ArithmeticFunction] notation "Λ" => ArithmeticFunction.vonMangoldt
@[inherit_doc] scoped[ArithmeticFunction.vonMangoldt] notation "Λ" =>
ArithmeticFunction.vonMangoldt
theorem vonMangoldt_apply {n : ℕ} : Λ n = if IsPrimePow n then Real.log (minFac n) else 0 :=
rfl
#align nat.arithmetic_function.von_mangoldt_apply ArithmeticFunction.vonMangoldt_apply
@[simp]
theorem vonMangoldt_apply_one : Λ 1 = 0 := by simp [vonMangoldt_apply]
#align nat.arithmetic_function.von_mangoldt_apply_one ArithmeticFunction.vonMangoldt_apply_one
@[simp]
theorem vonMangoldt_nonneg {n : ℕ} : 0 ≤ Λ n := by
rw [vonMangoldt_apply]
split_ifs
· exact Real.log_nonneg (one_le_cast.2 (Nat.minFac_pos n))
rfl
#align nat.arithmetic_function.von_mangoldt_nonneg ArithmeticFunction.vonMangoldt_nonneg
theorem vonMangoldt_apply_pow {n k : ℕ} (hk : k ≠ 0) : Λ (n ^ k) = Λ n := by
simp only [vonMangoldt_apply, isPrimePow_pow_iff hk, pow_minFac hk]
#align nat.arithmetic_function.von_mangoldt_apply_pow ArithmeticFunction.vonMangoldt_apply_pow
theorem vonMangoldt_apply_prime {p : ℕ} (hp : p.Prime) : Λ p = Real.log p := by
rw [vonMangoldt_apply, Prime.minFac_eq hp, if_pos hp.prime.isPrimePow]
#align nat.arithmetic_function.von_mangoldt_apply_prime ArithmeticFunction.vonMangoldt_apply_prime
theorem vonMangoldt_ne_zero_iff {n : ℕ} : Λ n ≠ 0 ↔ IsPrimePow n := by
rcases eq_or_ne n 1 with (rfl | hn); · simp [not_isPrimePow_one]
exact (Real.log_pos (one_lt_cast.2 (minFac_prime hn).one_lt)).ne'.ite_ne_right_iff
#align nat.arithmetic_function.von_mangoldt_ne_zero_iff ArithmeticFunction.vonMangoldt_ne_zero_iff
theorem vonMangoldt_pos_iff {n : ℕ} : 0 < Λ n ↔ IsPrimePow n :=
vonMangoldt_nonneg.lt_iff_ne.trans (ne_comm.trans vonMangoldt_ne_zero_iff)
#align nat.arithmetic_function.von_mangoldt_pos_iff ArithmeticFunction.vonMangoldt_pos_iff
theorem vonMangoldt_eq_zero_iff {n : ℕ} : Λ n = 0 ↔ ¬IsPrimePow n :=
vonMangoldt_ne_zero_iff.not_right
#align nat.arithmetic_function.von_mangoldt_eq_zero_iff ArithmeticFunction.vonMangoldt_eq_zero_iff
theorem vonMangoldt_sum {n : ℕ} : ∑ i ∈ n.divisors, Λ i = Real.log n := by
refine recOnPrimeCoprime ?_ ?_ ?_ n
· simp
· intro p k hp
rw [sum_divisors_prime_pow hp, cast_pow, Real.log_pow, Finset.sum_range_succ', Nat.pow_zero,
vonMangoldt_apply_one]
simp [vonMangoldt_apply_pow (Nat.succ_ne_zero _), vonMangoldt_apply_prime hp]
intro a b ha' hb' hab ha hb
simp only [vonMangoldt_apply, ← sum_filter] at ha hb ⊢
rw [mul_divisors_filter_prime_pow hab, filter_union,
sum_union (disjoint_divisors_filter_isPrimePow hab), ha, hb, Nat.cast_mul,
Real.log_mul (cast_ne_zero.2 (pos_of_gt ha').ne') (cast_ne_zero.2 (pos_of_gt hb').ne')]
#align nat.arithmetic_function.von_mangoldt_sum ArithmeticFunction.vonMangoldt_sum
@[simp]
theorem vonMangoldt_mul_zeta : Λ * ζ = log := by
ext n; rw [coe_mul_zeta_apply, vonMangoldt_sum]; rfl
#align nat.arithmetic_function.von_mangoldt_mul_zeta ArithmeticFunction.vonMangoldt_mul_zeta
@[simp]
theorem zeta_mul_vonMangoldt : (ζ : ArithmeticFunction ℝ) * Λ = log := by rw [mul_comm]; simp
#align nat.arithmetic_function.zeta_mul_von_mangoldt ArithmeticFunction.zeta_mul_vonMangoldt
@[simp]
| Mathlib/NumberTheory/VonMangoldt.lean | 135 | 136 | theorem log_mul_moebius_eq_vonMangoldt : log * μ = Λ := by |
rw [← vonMangoldt_mul_zeta, mul_assoc, coe_zeta_mul_coe_moebius, mul_one]
|
import Mathlib.LinearAlgebra.Basis.VectorSpace
import Mathlib.LinearAlgebra.Dimension.Constructions
import Mathlib.LinearAlgebra.Dimension.Finite
#align_import field_theory.finiteness from "leanprover-community/mathlib"@"039a089d2a4b93c761b234f3e5f5aeb752bac60f"
universe u v
open scoped Classical
open Cardinal
open Cardinal Submodule Module Function
namespace IsNoetherian
variable {K : Type u} {V : Type v} [DivisionRing K] [AddCommGroup V] [Module K V]
| Mathlib/FieldTheory/Finiteness.lean | 32 | 43 | theorem iff_rank_lt_aleph0 : IsNoetherian K V ↔ Module.rank K V < ℵ₀ := by |
let b := Basis.ofVectorSpace K V
rw [← b.mk_eq_rank'', lt_aleph0_iff_set_finite]
constructor
· intro
exact (Basis.ofVectorSpaceIndex.linearIndependent K V).set_finite_of_isNoetherian
· intro hbfinite
refine
@isNoetherian_of_linearEquiv K (⊤ : Submodule K V) V _ _ _ _ _ (LinearEquiv.ofTop _ rfl)
(id ?_)
refine isNoetherian_of_fg_of_noetherian _ ⟨Set.Finite.toFinset hbfinite, ?_⟩
rw [Set.Finite.coe_toFinset, ← b.span_eq, Basis.coe_ofVectorSpace, Subtype.range_coe]
|
import Mathlib.Algebra.Ring.Prod
import Mathlib.GroupTheory.OrderOfElement
import Mathlib.Tactic.FinCases
#align_import data.zmod.basic from "leanprover-community/mathlib"@"74ad1c88c77e799d2fea62801d1dbbd698cff1b7"
assert_not_exists Submodule
open Function
namespace ZMod
instance charZero : CharZero (ZMod 0) := inferInstanceAs (CharZero ℤ)
def val : ∀ {n : ℕ}, ZMod n → ℕ
| 0 => Int.natAbs
| n + 1 => ((↑) : Fin (n + 1) → ℕ)
#align zmod.val ZMod.val
theorem val_lt {n : ℕ} [NeZero n] (a : ZMod n) : a.val < n := by
cases n
· cases NeZero.ne 0 rfl
exact Fin.is_lt a
#align zmod.val_lt ZMod.val_lt
theorem val_le {n : ℕ} [NeZero n] (a : ZMod n) : a.val ≤ n :=
a.val_lt.le
#align zmod.val_le ZMod.val_le
@[simp]
theorem val_zero : ∀ {n}, (0 : ZMod n).val = 0
| 0 => rfl
| _ + 1 => rfl
#align zmod.val_zero ZMod.val_zero
@[simp]
theorem val_one' : (1 : ZMod 0).val = 1 :=
rfl
#align zmod.val_one' ZMod.val_one'
@[simp]
theorem val_neg' {n : ZMod 0} : (-n).val = n.val :=
Int.natAbs_neg n
#align zmod.val_neg' ZMod.val_neg'
@[simp]
theorem val_mul' {m n : ZMod 0} : (m * n).val = m.val * n.val :=
Int.natAbs_mul m n
#align zmod.val_mul' ZMod.val_mul'
@[simp]
theorem val_natCast {n : ℕ} (a : ℕ) : (a : ZMod n).val = a % n := by
cases n
· rw [Nat.mod_zero]
exact Int.natAbs_ofNat a
· apply Fin.val_natCast
#align zmod.val_nat_cast ZMod.val_natCast
@[deprecated (since := "2024-04-17")]
alias val_nat_cast := val_natCast
theorem val_unit' {n : ZMod 0} : IsUnit n ↔ n.val = 1 := by
simp only [val]
rw [Int.isUnit_iff, Int.natAbs_eq_iff, Nat.cast_one]
lemma eq_one_of_isUnit_natCast {n : ℕ} (h : IsUnit (n : ZMod 0)) : n = 1 := by
rw [← Nat.mod_zero n, ← val_natCast, val_unit'.mp h]
theorem val_natCast_of_lt {n a : ℕ} (h : a < n) : (a : ZMod n).val = a := by
rwa [val_natCast, Nat.mod_eq_of_lt]
@[deprecated (since := "2024-04-17")]
alias val_nat_cast_of_lt := val_natCast_of_lt
instance charP (n : ℕ) : CharP (ZMod n) n where
cast_eq_zero_iff' := by
intro k
cases' n with n
· simp [zero_dvd_iff, Int.natCast_eq_zero, Nat.zero_eq]
· exact Fin.natCast_eq_zero
@[simp]
theorem addOrderOf_one (n : ℕ) : addOrderOf (1 : ZMod n) = n :=
CharP.eq _ (CharP.addOrderOf_one _) (ZMod.charP n)
#align zmod.add_order_of_one ZMod.addOrderOf_one
@[simp]
theorem addOrderOf_coe (a : ℕ) {n : ℕ} (n0 : n ≠ 0) : addOrderOf (a : ZMod n) = n / n.gcd a := by
cases' a with a
· simp only [Nat.zero_eq, Nat.cast_zero, addOrderOf_zero, Nat.gcd_zero_right,
Nat.pos_of_ne_zero n0, Nat.div_self]
rw [← Nat.smul_one_eq_cast, addOrderOf_nsmul' _ a.succ_ne_zero, ZMod.addOrderOf_one]
#align zmod.add_order_of_coe ZMod.addOrderOf_coe
@[simp]
theorem addOrderOf_coe' {a : ℕ} (n : ℕ) (a0 : a ≠ 0) : addOrderOf (a : ZMod n) = n / n.gcd a := by
rw [← Nat.smul_one_eq_cast, addOrderOf_nsmul' _ a0, ZMod.addOrderOf_one]
#align zmod.add_order_of_coe' ZMod.addOrderOf_coe'
theorem ringChar_zmod_n (n : ℕ) : ringChar (ZMod n) = n := by
rw [ringChar.eq_iff]
exact ZMod.charP n
#align zmod.ring_char_zmod_n ZMod.ringChar_zmod_n
-- @[simp] -- Porting note (#10618): simp can prove this
theorem natCast_self (n : ℕ) : (n : ZMod n) = 0 :=
CharP.cast_eq_zero (ZMod n) n
#align zmod.nat_cast_self ZMod.natCast_self
@[deprecated (since := "2024-04-17")]
alias nat_cast_self := natCast_self
@[simp]
theorem natCast_self' (n : ℕ) : (n + 1 : ZMod (n + 1)) = 0 := by
rw [← Nat.cast_add_one, natCast_self (n + 1)]
#align zmod.nat_cast_self' ZMod.natCast_self'
@[deprecated (since := "2024-04-17")]
alias nat_cast_self' := natCast_self'
section UniversalProperty
variable {n : ℕ} {R : Type*}
section
variable [AddGroupWithOne R]
def cast : ∀ {n : ℕ}, ZMod n → R
| 0 => Int.cast
| _ + 1 => fun i => i.val
#align zmod.cast ZMod.cast
@[simp]
theorem cast_zero : (cast (0 : ZMod n) : R) = 0 := by
delta ZMod.cast
cases n
· exact Int.cast_zero
· simp
#align zmod.cast_zero ZMod.cast_zero
theorem cast_eq_val [NeZero n] (a : ZMod n) : (cast a : R) = a.val := by
cases n
· cases NeZero.ne 0 rfl
rfl
#align zmod.cast_eq_val ZMod.cast_eq_val
variable {S : Type*} [AddGroupWithOne S]
@[simp]
theorem _root_.Prod.fst_zmod_cast (a : ZMod n) : (cast a : R × S).fst = cast a := by
cases n
· rfl
· simp [ZMod.cast]
#align prod.fst_zmod_cast Prod.fst_zmod_cast
@[simp]
theorem _root_.Prod.snd_zmod_cast (a : ZMod n) : (cast a : R × S).snd = cast a := by
cases n
· rfl
· simp [ZMod.cast]
#align prod.snd_zmod_cast Prod.snd_zmod_cast
end
theorem natCast_zmod_val {n : ℕ} [NeZero n] (a : ZMod n) : (a.val : ZMod n) = a := by
cases n
· cases NeZero.ne 0 rfl
· apply Fin.cast_val_eq_self
#align zmod.nat_cast_zmod_val ZMod.natCast_zmod_val
@[deprecated (since := "2024-04-17")]
alias nat_cast_zmod_val := natCast_zmod_val
theorem natCast_rightInverse [NeZero n] : Function.RightInverse val ((↑) : ℕ → ZMod n) :=
natCast_zmod_val
#align zmod.nat_cast_right_inverse ZMod.natCast_rightInverse
@[deprecated (since := "2024-04-17")]
alias nat_cast_rightInverse := natCast_rightInverse
theorem natCast_zmod_surjective [NeZero n] : Function.Surjective ((↑) : ℕ → ZMod n) :=
natCast_rightInverse.surjective
#align zmod.nat_cast_zmod_surjective ZMod.natCast_zmod_surjective
@[deprecated (since := "2024-04-17")]
alias nat_cast_zmod_surjective := natCast_zmod_surjective
@[norm_cast]
theorem intCast_zmod_cast (a : ZMod n) : ((cast a : ℤ) : ZMod n) = a := by
cases n
· simp [ZMod.cast, ZMod]
· dsimp [ZMod.cast, ZMod]
erw [Int.cast_natCast, Fin.cast_val_eq_self]
#align zmod.int_cast_zmod_cast ZMod.intCast_zmod_cast
@[deprecated (since := "2024-04-17")]
alias int_cast_zmod_cast := intCast_zmod_cast
theorem intCast_rightInverse : Function.RightInverse (cast : ZMod n → ℤ) ((↑) : ℤ → ZMod n) :=
intCast_zmod_cast
#align zmod.int_cast_right_inverse ZMod.intCast_rightInverse
@[deprecated (since := "2024-04-17")]
alias int_cast_rightInverse := intCast_rightInverse
theorem intCast_surjective : Function.Surjective ((↑) : ℤ → ZMod n) :=
intCast_rightInverse.surjective
#align zmod.int_cast_surjective ZMod.intCast_surjective
@[deprecated (since := "2024-04-17")]
alias int_cast_surjective := intCast_surjective
theorem cast_id : ∀ (n) (i : ZMod n), (ZMod.cast i : ZMod n) = i
| 0, _ => Int.cast_id
| _ + 1, i => natCast_zmod_val i
#align zmod.cast_id ZMod.cast_id
@[simp]
theorem cast_id' : (ZMod.cast : ZMod n → ZMod n) = id :=
funext (cast_id n)
#align zmod.cast_id' ZMod.cast_id'
variable (R) [Ring R]
@[simp]
theorem natCast_comp_val [NeZero n] : ((↑) : ℕ → R) ∘ (val : ZMod n → ℕ) = cast := by
cases n
· cases NeZero.ne 0 rfl
rfl
#align zmod.nat_cast_comp_val ZMod.natCast_comp_val
@[deprecated (since := "2024-04-17")]
alias nat_cast_comp_val := natCast_comp_val
@[simp]
theorem intCast_comp_cast : ((↑) : ℤ → R) ∘ (cast : ZMod n → ℤ) = cast := by
cases n
· exact congr_arg (Int.cast ∘ ·) ZMod.cast_id'
· ext
simp [ZMod, ZMod.cast]
#align zmod.int_cast_comp_cast ZMod.intCast_comp_cast
@[deprecated (since := "2024-04-17")]
alias int_cast_comp_cast := intCast_comp_cast
variable {R}
@[simp]
theorem natCast_val [NeZero n] (i : ZMod n) : (i.val : R) = cast i :=
congr_fun (natCast_comp_val R) i
#align zmod.nat_cast_val ZMod.natCast_val
@[deprecated (since := "2024-04-17")]
alias nat_cast_val := natCast_val
@[simp]
theorem intCast_cast (i : ZMod n) : ((cast i : ℤ) : R) = cast i :=
congr_fun (intCast_comp_cast R) i
#align zmod.int_cast_cast ZMod.intCast_cast
@[deprecated (since := "2024-04-17")]
alias int_cast_cast := intCast_cast
| Mathlib/Data/ZMod/Basic.lean | 312 | 324 | theorem cast_add_eq_ite {n : ℕ} (a b : ZMod n) :
(cast (a + b) : ℤ) =
if (n : ℤ) ≤ cast a + cast b then (cast a + cast b - n : ℤ) else cast a + cast b := by |
cases' n with n
· simp; rfl
change Fin (n + 1) at a b
change ((((a + b) : Fin (n + 1)) : ℕ) : ℤ) = if ((n + 1 : ℕ) : ℤ) ≤ (a : ℕ) + b then _ else _
simp only [Fin.val_add_eq_ite, Int.ofNat_succ, Int.ofNat_le]
norm_cast
split_ifs with h
· rw [Nat.cast_sub h]
congr
· rfl
|
import Mathlib.NumberTheory.DirichletCharacter.Bounds
import Mathlib.NumberTheory.EulerProduct.Basic
import Mathlib.NumberTheory.LSeries.Basic
import Mathlib.NumberTheory.LSeries.RiemannZeta
open Complex
variable {s : ℂ}
noncomputable
def riemannZetaSummandHom (hs : s ≠ 0) : ℕ →*₀ ℂ where
toFun n := (n : ℂ) ^ (-s)
map_zero' := by simp [hs]
map_one' := by simp
map_mul' m n := by
simpa only [Nat.cast_mul, ofReal_natCast]
using mul_cpow_ofReal_nonneg m.cast_nonneg n.cast_nonneg _
noncomputable
def dirichletSummandHom {n : ℕ} (χ : DirichletCharacter ℂ n) (hs : s ≠ 0) : ℕ →*₀ ℂ where
toFun n := χ n * (n : ℂ) ^ (-s)
map_zero' := by simp [hs]
map_one' := by simp
map_mul' m n := by
simp_rw [← ofReal_natCast]
simpa only [Nat.cast_mul, IsUnit.mul_iff, not_and, map_mul, ofReal_mul,
mul_cpow_ofReal_nonneg m.cast_nonneg n.cast_nonneg _]
using mul_mul_mul_comm ..
lemma summable_riemannZetaSummand (hs : 1 < s.re) :
Summable (fun n ↦ ‖riemannZetaSummandHom (ne_zero_of_one_lt_re hs) n‖) := by
simp only [riemannZetaSummandHom, MonoidWithZeroHom.coe_mk, ZeroHom.coe_mk]
convert Real.summable_nat_rpow_inv.mpr hs with n
rw [← ofReal_natCast, Complex.norm_eq_abs,
abs_cpow_eq_rpow_re_of_nonneg (Nat.cast_nonneg n) <| re_neg_ne_zero_of_one_lt_re hs,
neg_re, Real.rpow_neg <| Nat.cast_nonneg n]
lemma tsum_riemannZetaSummand (hs : 1 < s.re) :
∑' (n : ℕ), riemannZetaSummandHom (ne_zero_of_one_lt_re hs) n = riemannZeta s := by
have hsum := summable_riemannZetaSummand hs
rw [zeta_eq_tsum_one_div_nat_add_one_cpow hs, tsum_eq_zero_add hsum.of_norm, map_zero, zero_add]
simp only [riemannZetaSummandHom, cpow_neg, MonoidWithZeroHom.coe_mk, ZeroHom.coe_mk,
Nat.cast_add, Nat.cast_one, one_div]
lemma summable_dirichletSummand {N : ℕ} (χ : DirichletCharacter ℂ N) (hs : 1 < s.re) :
Summable (fun n ↦ ‖dirichletSummandHom χ (ne_zero_of_one_lt_re hs) n‖) := by
simp only [dirichletSummandHom, MonoidWithZeroHom.coe_mk, ZeroHom.coe_mk, norm_mul]
exact (summable_riemannZetaSummand hs).of_nonneg_of_le (fun _ ↦ by positivity)
(fun n ↦ mul_le_of_le_one_left (norm_nonneg _) <| χ.norm_le_one n)
open scoped LSeries.notation in
lemma tsum_dirichletSummand {N : ℕ} (χ : DirichletCharacter ℂ N) (hs : 1 < s.re) :
∑' (n : ℕ), dirichletSummandHom χ (ne_zero_of_one_lt_re hs) n = L ↗χ s := by
simp only [LSeries, LSeries.term, dirichletSummandHom]
refine tsum_congr (fun n ↦ ?_)
rcases eq_or_ne n 0 with rfl | hn
· simp only [map_zero, ↓reduceIte]
· simp only [cpow_neg, MonoidWithZeroHom.coe_mk, ZeroHom.coe_mk, hn, ↓reduceIte,
Field.div_eq_mul_inv]
open Filter Nat Topology EulerProduct
theorem riemannZeta_eulerProduct_hasProd (hs : 1 < s.re) :
HasProd (fun p : Primes ↦ (1 - (p : ℂ) ^ (-s))⁻¹) (riemannZeta s) := by
rw [← tsum_riemannZetaSummand hs]
apply eulerProduct_completely_multiplicative_hasProd <| summable_riemannZetaSummand hs
theorem riemannZeta_eulerProduct_tprod (hs : 1 < s.re) :
∏' p : Primes, (1 - (p : ℂ) ^ (-s))⁻¹ = riemannZeta s :=
(riemannZeta_eulerProduct_hasProd hs).tprod_eq
theorem riemannZeta_eulerProduct (hs : 1 < s.re) :
Tendsto (fun n : ℕ ↦ ∏ p ∈ primesBelow n, (1 - (p : ℂ) ^ (-s))⁻¹) atTop
(𝓝 (riemannZeta s)) := by
rw [← tsum_riemannZetaSummand hs]
apply eulerProduct_completely_multiplicative <| summable_riemannZetaSummand hs
open scoped LSeries.notation
| Mathlib/NumberTheory/EulerProduct/DirichletLSeries.lean | 114 | 118 | theorem dirichletLSeries_eulerProduct_hasProd {N : ℕ} (χ : DirichletCharacter ℂ N)
(hs : 1 < s.re) :
HasProd (fun p : Primes ↦ (1 - χ p * (p : ℂ) ^ (-s))⁻¹) (L ↗χ s) := by |
rw [← tsum_dirichletSummand χ hs]
convert eulerProduct_completely_multiplicative_hasProd <| summable_dirichletSummand χ hs
|
import Mathlib.Algebra.Field.ULift
import Mathlib.Algebra.MvPolynomial.Cardinal
import Mathlib.Data.Nat.Factorization.PrimePow
import Mathlib.Data.Rat.Denumerable
import Mathlib.FieldTheory.Finite.GaloisField
import Mathlib.Logic.Equiv.TransferInstance
import Mathlib.RingTheory.Localization.Cardinality
import Mathlib.SetTheory.Cardinal.Divisibility
#align_import field_theory.cardinality from "leanprover-community/mathlib"@"0723536a0522d24fc2f159a096fb3304bef77472"
local notation "‖" x "‖" => Fintype.card x
open scoped Cardinal nonZeroDivisors
universe u
| Mathlib/FieldTheory/Cardinality.lean | 40 | 49 | theorem Fintype.isPrimePow_card_of_field {α} [Fintype α] [Field α] : IsPrimePow ‖α‖ := by |
-- TODO: `Algebra` version of `CharP.exists`, of type `∀ p, Algebra (ZMod p) α`
cases' CharP.exists α with p _
haveI hp := Fact.mk (CharP.char_is_prime α p)
letI : Algebra (ZMod p) α := ZMod.algebra _ _
let b := IsNoetherian.finsetBasis (ZMod p) α
rw [Module.card_fintype b, ZMod.card, isPrimePow_pow_iff]
· exact hp.1.isPrimePow
rw [← FiniteDimensional.finrank_eq_card_basis b]
exact FiniteDimensional.finrank_pos.ne'
|
import Mathlib.Data.Real.Basic
import Mathlib.Data.ENNReal.Real
import Mathlib.Data.Sign
#align_import data.real.ereal from "leanprover-community/mathlib"@"2196ab363eb097c008d4497125e0dde23fb36db2"
open Function ENNReal NNReal Set
noncomputable section
def EReal := WithBot (WithTop ℝ)
deriving Bot, Zero, One, Nontrivial, AddMonoid, PartialOrder
#align ereal EReal
instance : ZeroLEOneClass EReal := inferInstanceAs (ZeroLEOneClass (WithBot (WithTop ℝ)))
instance : SupSet EReal := inferInstanceAs (SupSet (WithBot (WithTop ℝ)))
instance : InfSet EReal := inferInstanceAs (InfSet (WithBot (WithTop ℝ)))
instance : CompleteLinearOrder EReal :=
inferInstanceAs (CompleteLinearOrder (WithBot (WithTop ℝ)))
instance : LinearOrderedAddCommMonoid EReal :=
inferInstanceAs (LinearOrderedAddCommMonoid (WithBot (WithTop ℝ)))
instance : AddCommMonoidWithOne EReal :=
inferInstanceAs (AddCommMonoidWithOne (WithBot (WithTop ℝ)))
instance : DenselyOrdered EReal :=
inferInstanceAs (DenselyOrdered (WithBot (WithTop ℝ)))
@[coe] def Real.toEReal : ℝ → EReal := some ∘ some
#align real.to_ereal Real.toEReal
namespace EReal
-- things unify with `WithBot.decidableLT` later if we don't provide this explicitly.
instance decidableLT : DecidableRel ((· < ·) : EReal → EReal → Prop) :=
WithBot.decidableLT
#align ereal.decidable_lt EReal.decidableLT
-- TODO: Provide explicitly, otherwise it is inferred noncomputably from `CompleteLinearOrder`
instance : Top EReal := ⟨some ⊤⟩
instance : Coe ℝ EReal := ⟨Real.toEReal⟩
theorem coe_strictMono : StrictMono Real.toEReal :=
WithBot.coe_strictMono.comp WithTop.coe_strictMono
#align ereal.coe_strict_mono EReal.coe_strictMono
theorem coe_injective : Injective Real.toEReal :=
coe_strictMono.injective
#align ereal.coe_injective EReal.coe_injective
@[simp, norm_cast]
protected theorem coe_le_coe_iff {x y : ℝ} : (x : EReal) ≤ (y : EReal) ↔ x ≤ y :=
coe_strictMono.le_iff_le
#align ereal.coe_le_coe_iff EReal.coe_le_coe_iff
@[simp, norm_cast]
protected theorem coe_lt_coe_iff {x y : ℝ} : (x : EReal) < (y : EReal) ↔ x < y :=
coe_strictMono.lt_iff_lt
#align ereal.coe_lt_coe_iff EReal.coe_lt_coe_iff
@[simp, norm_cast]
protected theorem coe_eq_coe_iff {x y : ℝ} : (x : EReal) = (y : EReal) ↔ x = y :=
coe_injective.eq_iff
#align ereal.coe_eq_coe_iff EReal.coe_eq_coe_iff
protected theorem coe_ne_coe_iff {x y : ℝ} : (x : EReal) ≠ (y : EReal) ↔ x ≠ y :=
coe_injective.ne_iff
#align ereal.coe_ne_coe_iff EReal.coe_ne_coe_iff
@[coe] def _root_.ENNReal.toEReal : ℝ≥0∞ → EReal
| ⊤ => ⊤
| .some x => x.1
#align ennreal.to_ereal ENNReal.toEReal
instance hasCoeENNReal : Coe ℝ≥0∞ EReal :=
⟨ENNReal.toEReal⟩
#align ereal.has_coe_ennreal EReal.hasCoeENNReal
instance : Inhabited EReal := ⟨0⟩
@[simp, norm_cast]
theorem coe_zero : ((0 : ℝ) : EReal) = 0 := rfl
#align ereal.coe_zero EReal.coe_zero
@[simp, norm_cast]
theorem coe_one : ((1 : ℝ) : EReal) = 1 := rfl
#align ereal.coe_one EReal.coe_one
@[elab_as_elim, induction_eliminator, cases_eliminator]
protected def rec {C : EReal → Sort*} (h_bot : C ⊥) (h_real : ∀ a : ℝ, C a) (h_top : C ⊤) :
∀ a : EReal, C a
| ⊥ => h_bot
| (a : ℝ) => h_real a
| ⊤ => h_top
#align ereal.rec EReal.rec
protected def mul : EReal → EReal → EReal
| ⊥, ⊥ => ⊤
| ⊥, ⊤ => ⊥
| ⊥, (y : ℝ) => if 0 < y then ⊥ else if y = 0 then 0 else ⊤
| ⊤, ⊥ => ⊥
| ⊤, ⊤ => ⊤
| ⊤, (y : ℝ) => if 0 < y then ⊤ else if y = 0 then 0 else ⊥
| (x : ℝ), ⊤ => if 0 < x then ⊤ else if x = 0 then 0 else ⊥
| (x : ℝ), ⊥ => if 0 < x then ⊥ else if x = 0 then 0 else ⊤
| (x : ℝ), (y : ℝ) => (x * y : ℝ)
#align ereal.mul EReal.mul
instance : Mul EReal := ⟨EReal.mul⟩
@[simp, norm_cast]
theorem coe_mul (x y : ℝ) : (↑(x * y) : EReal) = x * y :=
rfl
#align ereal.coe_mul EReal.coe_mul
@[elab_as_elim]
theorem induction₂ {P : EReal → EReal → Prop} (top_top : P ⊤ ⊤) (top_pos : ∀ x : ℝ, 0 < x → P ⊤ x)
(top_zero : P ⊤ 0) (top_neg : ∀ x : ℝ, x < 0 → P ⊤ x) (top_bot : P ⊤ ⊥)
(pos_top : ∀ x : ℝ, 0 < x → P x ⊤) (pos_bot : ∀ x : ℝ, 0 < x → P x ⊥) (zero_top : P 0 ⊤)
(coe_coe : ∀ x y : ℝ, P x y) (zero_bot : P 0 ⊥) (neg_top : ∀ x : ℝ, x < 0 → P x ⊤)
(neg_bot : ∀ x : ℝ, x < 0 → P x ⊥) (bot_top : P ⊥ ⊤) (bot_pos : ∀ x : ℝ, 0 < x → P ⊥ x)
(bot_zero : P ⊥ 0) (bot_neg : ∀ x : ℝ, x < 0 → P ⊥ x) (bot_bot : P ⊥ ⊥) : ∀ x y, P x y
| ⊥, ⊥ => bot_bot
| ⊥, (y : ℝ) => by
rcases lt_trichotomy y 0 with (hy | rfl | hy)
exacts [bot_neg y hy, bot_zero, bot_pos y hy]
| ⊥, ⊤ => bot_top
| (x : ℝ), ⊥ => by
rcases lt_trichotomy x 0 with (hx | rfl | hx)
exacts [neg_bot x hx, zero_bot, pos_bot x hx]
| (x : ℝ), (y : ℝ) => coe_coe _ _
| (x : ℝ), ⊤ => by
rcases lt_trichotomy x 0 with (hx | rfl | hx)
exacts [neg_top x hx, zero_top, pos_top x hx]
| ⊤, ⊥ => top_bot
| ⊤, (y : ℝ) => by
rcases lt_trichotomy y 0 with (hy | rfl | hy)
exacts [top_neg y hy, top_zero, top_pos y hy]
| ⊤, ⊤ => top_top
#align ereal.induction₂ EReal.induction₂
@[elab_as_elim]
theorem induction₂_symm {P : EReal → EReal → Prop} (symm : ∀ {x y}, P x y → P y x)
(top_top : P ⊤ ⊤) (top_pos : ∀ x : ℝ, 0 < x → P ⊤ x) (top_zero : P ⊤ 0)
(top_neg : ∀ x : ℝ, x < 0 → P ⊤ x) (top_bot : P ⊤ ⊥) (pos_bot : ∀ x : ℝ, 0 < x → P x ⊥)
(coe_coe : ∀ x y : ℝ, P x y) (zero_bot : P 0 ⊥) (neg_bot : ∀ x : ℝ, x < 0 → P x ⊥)
(bot_bot : P ⊥ ⊥) : ∀ x y, P x y :=
@induction₂ P top_top top_pos top_zero top_neg top_bot (fun _ h => symm <| top_pos _ h)
pos_bot (symm top_zero) coe_coe zero_bot (fun _ h => symm <| top_neg _ h) neg_bot (symm top_bot)
(fun _ h => symm <| pos_bot _ h) (symm zero_bot) (fun _ h => symm <| neg_bot _ h) bot_bot
protected theorem mul_comm (x y : EReal) : x * y = y * x := by
induction' x with x <;> induction' y with y <;>
try { rfl }
rw [← coe_mul, ← coe_mul, mul_comm]
#align ereal.mul_comm EReal.mul_comm
protected theorem one_mul : ∀ x : EReal, 1 * x = x
| ⊤ => if_pos one_pos
| ⊥ => if_pos one_pos
| (x : ℝ) => congr_arg Real.toEReal (one_mul x)
protected theorem zero_mul : ∀ x : EReal, 0 * x = 0
| ⊤ => (if_neg (lt_irrefl _)).trans (if_pos rfl)
| ⊥ => (if_neg (lt_irrefl _)).trans (if_pos rfl)
| (x : ℝ) => congr_arg Real.toEReal (zero_mul x)
instance : MulZeroOneClass EReal where
one_mul := EReal.one_mul
mul_one := fun x => by rw [EReal.mul_comm, EReal.one_mul]
zero_mul := EReal.zero_mul
mul_zero := fun x => by rw [EReal.mul_comm, EReal.zero_mul]
instance canLift : CanLift EReal ℝ (↑) fun r => r ≠ ⊤ ∧ r ≠ ⊥ where
prf x hx := by
induction x
· simp at hx
· simp
· simp at hx
#align ereal.can_lift EReal.canLift
def toReal : EReal → ℝ
| ⊥ => 0
| ⊤ => 0
| (x : ℝ) => x
#align ereal.to_real EReal.toReal
@[simp]
theorem toReal_top : toReal ⊤ = 0 :=
rfl
#align ereal.to_real_top EReal.toReal_top
@[simp]
theorem toReal_bot : toReal ⊥ = 0 :=
rfl
#align ereal.to_real_bot EReal.toReal_bot
@[simp]
theorem toReal_zero : toReal 0 = 0 :=
rfl
#align ereal.to_real_zero EReal.toReal_zero
@[simp]
theorem toReal_one : toReal 1 = 1 :=
rfl
#align ereal.to_real_one EReal.toReal_one
@[simp]
theorem toReal_coe (x : ℝ) : toReal (x : EReal) = x :=
rfl
#align ereal.to_real_coe EReal.toReal_coe
@[simp]
theorem bot_lt_coe (x : ℝ) : (⊥ : EReal) < x :=
WithBot.bot_lt_coe _
#align ereal.bot_lt_coe EReal.bot_lt_coe
@[simp]
theorem coe_ne_bot (x : ℝ) : (x : EReal) ≠ ⊥ :=
(bot_lt_coe x).ne'
#align ereal.coe_ne_bot EReal.coe_ne_bot
@[simp]
theorem bot_ne_coe (x : ℝ) : (⊥ : EReal) ≠ x :=
(bot_lt_coe x).ne
#align ereal.bot_ne_coe EReal.bot_ne_coe
@[simp]
theorem coe_lt_top (x : ℝ) : (x : EReal) < ⊤ :=
WithBot.coe_lt_coe.2 <| WithTop.coe_lt_top _
#align ereal.coe_lt_top EReal.coe_lt_top
@[simp]
theorem coe_ne_top (x : ℝ) : (x : EReal) ≠ ⊤ :=
(coe_lt_top x).ne
#align ereal.coe_ne_top EReal.coe_ne_top
@[simp]
theorem top_ne_coe (x : ℝ) : (⊤ : EReal) ≠ x :=
(coe_lt_top x).ne'
#align ereal.top_ne_coe EReal.top_ne_coe
@[simp]
theorem bot_lt_zero : (⊥ : EReal) < 0 :=
bot_lt_coe 0
#align ereal.bot_lt_zero EReal.bot_lt_zero
@[simp]
theorem bot_ne_zero : (⊥ : EReal) ≠ 0 :=
(coe_ne_bot 0).symm
#align ereal.bot_ne_zero EReal.bot_ne_zero
@[simp]
theorem zero_ne_bot : (0 : EReal) ≠ ⊥ :=
coe_ne_bot 0
#align ereal.zero_ne_bot EReal.zero_ne_bot
@[simp]
theorem zero_lt_top : (0 : EReal) < ⊤ :=
coe_lt_top 0
#align ereal.zero_lt_top EReal.zero_lt_top
@[simp]
theorem zero_ne_top : (0 : EReal) ≠ ⊤ :=
coe_ne_top 0
#align ereal.zero_ne_top EReal.zero_ne_top
@[simp]
theorem top_ne_zero : (⊤ : EReal) ≠ 0 :=
(coe_ne_top 0).symm
#align ereal.top_ne_zero EReal.top_ne_zero
theorem range_coe : range Real.toEReal = {⊥, ⊤}ᶜ := by
ext x
induction x <;> simp
theorem range_coe_eq_Ioo : range Real.toEReal = Ioo ⊥ ⊤ := by
ext x
induction x <;> simp
@[simp, norm_cast]
theorem coe_add (x y : ℝ) : (↑(x + y) : EReal) = x + y :=
rfl
#align ereal.coe_add EReal.coe_add
-- `coe_mul` moved up
@[norm_cast]
theorem coe_nsmul (n : ℕ) (x : ℝ) : (↑(n • x) : EReal) = n • (x : EReal) :=
map_nsmul (⟨⟨Real.toEReal, coe_zero⟩, coe_add⟩ : ℝ →+ EReal) _ _
#align ereal.coe_nsmul EReal.coe_nsmul
#noalign ereal.coe_bit0
#noalign ereal.coe_bit1
@[simp, norm_cast]
theorem coe_eq_zero {x : ℝ} : (x : EReal) = 0 ↔ x = 0 :=
EReal.coe_eq_coe_iff
#align ereal.coe_eq_zero EReal.coe_eq_zero
@[simp, norm_cast]
theorem coe_eq_one {x : ℝ} : (x : EReal) = 1 ↔ x = 1 :=
EReal.coe_eq_coe_iff
#align ereal.coe_eq_one EReal.coe_eq_one
theorem coe_ne_zero {x : ℝ} : (x : EReal) ≠ 0 ↔ x ≠ 0 :=
EReal.coe_ne_coe_iff
#align ereal.coe_ne_zero EReal.coe_ne_zero
theorem coe_ne_one {x : ℝ} : (x : EReal) ≠ 1 ↔ x ≠ 1 :=
EReal.coe_ne_coe_iff
#align ereal.coe_ne_one EReal.coe_ne_one
@[simp, norm_cast]
protected theorem coe_nonneg {x : ℝ} : (0 : EReal) ≤ x ↔ 0 ≤ x :=
EReal.coe_le_coe_iff
#align ereal.coe_nonneg EReal.coe_nonneg
@[simp, norm_cast]
protected theorem coe_nonpos {x : ℝ} : (x : EReal) ≤ 0 ↔ x ≤ 0 :=
EReal.coe_le_coe_iff
#align ereal.coe_nonpos EReal.coe_nonpos
@[simp, norm_cast]
protected theorem coe_pos {x : ℝ} : (0 : EReal) < x ↔ 0 < x :=
EReal.coe_lt_coe_iff
#align ereal.coe_pos EReal.coe_pos
@[simp, norm_cast]
protected theorem coe_neg' {x : ℝ} : (x : EReal) < 0 ↔ x < 0 :=
EReal.coe_lt_coe_iff
#align ereal.coe_neg' EReal.coe_neg'
theorem toReal_le_toReal {x y : EReal} (h : x ≤ y) (hx : x ≠ ⊥) (hy : y ≠ ⊤) :
x.toReal ≤ y.toReal := by
lift x to ℝ using ⟨ne_top_of_le_ne_top hy h, hx⟩
lift y to ℝ using ⟨hy, ne_bot_of_le_ne_bot hx h⟩
simpa using h
#align ereal.to_real_le_to_real EReal.toReal_le_toReal
theorem coe_toReal {x : EReal} (hx : x ≠ ⊤) (h'x : x ≠ ⊥) : (x.toReal : EReal) = x := by
lift x to ℝ using ⟨hx, h'x⟩
rfl
#align ereal.coe_to_real EReal.coe_toReal
theorem le_coe_toReal {x : EReal} (h : x ≠ ⊤) : x ≤ x.toReal := by
by_cases h' : x = ⊥
· simp only [h', bot_le]
· simp only [le_refl, coe_toReal h h']
#align ereal.le_coe_to_real EReal.le_coe_toReal
theorem coe_toReal_le {x : EReal} (h : x ≠ ⊥) : ↑x.toReal ≤ x := by
by_cases h' : x = ⊤
· simp only [h', le_top]
· simp only [le_refl, coe_toReal h' h]
#align ereal.coe_to_real_le EReal.coe_toReal_le
theorem eq_top_iff_forall_lt (x : EReal) : x = ⊤ ↔ ∀ y : ℝ, (y : EReal) < x := by
constructor
· rintro rfl
exact EReal.coe_lt_top
· contrapose!
intro h
exact ⟨x.toReal, le_coe_toReal h⟩
#align ereal.eq_top_iff_forall_lt EReal.eq_top_iff_forall_lt
theorem eq_bot_iff_forall_lt (x : EReal) : x = ⊥ ↔ ∀ y : ℝ, x < (y : EReal) := by
constructor
· rintro rfl
exact bot_lt_coe
· contrapose!
intro h
exact ⟨x.toReal, coe_toReal_le h⟩
#align ereal.eq_bot_iff_forall_lt EReal.eq_bot_iff_forall_lt
lemma exists_between_coe_real {x z : EReal} (h : x < z) : ∃ y : ℝ, x < y ∧ y < z := by
obtain ⟨a, ha₁, ha₂⟩ := exists_between h
induction a with
| h_bot => exact (not_lt_bot ha₁).elim
| h_real a₀ => exact ⟨a₀, ha₁, ha₂⟩
| h_top => exact (not_top_lt ha₂).elim
@[simp]
lemma image_coe_Icc (x y : ℝ) : Real.toEReal '' Icc x y = Icc ↑x ↑y := by
refine (image_comp WithBot.some WithTop.some _).trans ?_
rw [WithTop.image_coe_Icc, WithBot.image_coe_Icc]
rfl
@[simp]
lemma image_coe_Ico (x y : ℝ) : Real.toEReal '' Ico x y = Ico ↑x ↑y := by
refine (image_comp WithBot.some WithTop.some _).trans ?_
rw [WithTop.image_coe_Ico, WithBot.image_coe_Ico]
rfl
@[simp]
lemma image_coe_Ici (x : ℝ) : Real.toEReal '' Ici x = Ico ↑x ⊤ := by
refine (image_comp WithBot.some WithTop.some _).trans ?_
rw [WithTop.image_coe_Ici, WithBot.image_coe_Ico]
rfl
@[simp]
lemma image_coe_Ioc (x y : ℝ) : Real.toEReal '' Ioc x y = Ioc ↑x ↑y := by
refine (image_comp WithBot.some WithTop.some _).trans ?_
rw [WithTop.image_coe_Ioc, WithBot.image_coe_Ioc]
rfl
@[simp]
lemma image_coe_Ioo (x y : ℝ) : Real.toEReal '' Ioo x y = Ioo ↑x ↑y := by
refine (image_comp WithBot.some WithTop.some _).trans ?_
rw [WithTop.image_coe_Ioo, WithBot.image_coe_Ioo]
rfl
@[simp]
lemma image_coe_Ioi (x : ℝ) : Real.toEReal '' Ioi x = Ioo ↑x ⊤ := by
refine (image_comp WithBot.some WithTop.some _).trans ?_
rw [WithTop.image_coe_Ioi, WithBot.image_coe_Ioo]
rfl
@[simp]
lemma image_coe_Iic (x : ℝ) : Real.toEReal '' Iic x = Ioc ⊥ ↑x := by
refine (image_comp WithBot.some WithTop.some _).trans ?_
rw [WithTop.image_coe_Iic, WithBot.image_coe_Iic]
rfl
@[simp]
lemma image_coe_Iio (x : ℝ) : Real.toEReal '' Iio x = Ioo ⊥ ↑x := by
refine (image_comp WithBot.some WithTop.some _).trans ?_
rw [WithTop.image_coe_Iio, WithBot.image_coe_Iio]
rfl
@[simp]
lemma preimage_coe_Ici (x : ℝ) : Real.toEReal ⁻¹' Ici x = Ici x := by
change (WithBot.some ∘ WithTop.some) ⁻¹' (Ici (WithBot.some (WithTop.some x))) = _
refine preimage_comp.trans ?_
simp only [WithBot.preimage_coe_Ici, WithTop.preimage_coe_Ici]
@[simp]
lemma preimage_coe_Ioi (x : ℝ) : Real.toEReal ⁻¹' Ioi x = Ioi x := by
change (WithBot.some ∘ WithTop.some) ⁻¹' (Ioi (WithBot.some (WithTop.some x))) = _
refine preimage_comp.trans ?_
simp only [WithBot.preimage_coe_Ioi, WithTop.preimage_coe_Ioi]
@[simp]
lemma preimage_coe_Ioi_bot : Real.toEReal ⁻¹' Ioi ⊥ = univ := by
change (WithBot.some ∘ WithTop.some) ⁻¹' (Ioi ⊥) = _
refine preimage_comp.trans ?_
simp only [WithBot.preimage_coe_Ioi_bot, preimage_univ]
@[simp]
lemma preimage_coe_Iic (y : ℝ) : Real.toEReal ⁻¹' Iic y = Iic y := by
change (WithBot.some ∘ WithTop.some) ⁻¹' (Iic (WithBot.some (WithTop.some y))) = _
refine preimage_comp.trans ?_
simp only [WithBot.preimage_coe_Iic, WithTop.preimage_coe_Iic]
@[simp]
lemma preimage_coe_Iio (y : ℝ) : Real.toEReal ⁻¹' Iio y = Iio y := by
change (WithBot.some ∘ WithTop.some) ⁻¹' (Iio (WithBot.some (WithTop.some y))) = _
refine preimage_comp.trans ?_
simp only [WithBot.preimage_coe_Iio, WithTop.preimage_coe_Iio]
@[simp]
lemma preimage_coe_Iio_top : Real.toEReal ⁻¹' Iio ⊤ = univ := by
change (WithBot.some ∘ WithTop.some) ⁻¹' (Iio (WithBot.some ⊤)) = _
refine preimage_comp.trans ?_
simp only [WithBot.preimage_coe_Iio, WithTop.preimage_coe_Iio_top]
@[simp]
lemma preimage_coe_Icc (x y : ℝ) : Real.toEReal ⁻¹' Icc x y = Icc x y := by
simp_rw [← Ici_inter_Iic]
simp
@[simp]
lemma preimage_coe_Ico (x y : ℝ) : Real.toEReal ⁻¹' Ico x y = Ico x y := by
simp_rw [← Ici_inter_Iio]
simp
@[simp]
lemma preimage_coe_Ioc (x y : ℝ) : Real.toEReal ⁻¹' Ioc x y = Ioc x y := by
simp_rw [← Ioi_inter_Iic]
simp
@[simp]
lemma preimage_coe_Ioo (x y : ℝ) : Real.toEReal ⁻¹' Ioo x y = Ioo x y := by
simp_rw [← Ioi_inter_Iio]
simp
@[simp]
lemma preimage_coe_Ico_top (x : ℝ) : Real.toEReal ⁻¹' Ico x ⊤ = Ici x := by
rw [← Ici_inter_Iio]
simp
@[simp]
lemma preimage_coe_Ioo_top (x : ℝ) : Real.toEReal ⁻¹' Ioo x ⊤ = Ioi x := by
rw [← Ioi_inter_Iio]
simp
@[simp]
lemma preimage_coe_Ioc_bot (y : ℝ) : Real.toEReal ⁻¹' Ioc ⊥ y = Iic y := by
rw [← Ioi_inter_Iic]
simp
@[simp]
lemma preimage_coe_Ioo_bot (y : ℝ) : Real.toEReal ⁻¹' Ioo ⊥ y = Iio y := by
rw [← Ioi_inter_Iio]
simp
@[simp]
lemma preimage_coe_Ioo_bot_top : Real.toEReal ⁻¹' Ioo ⊥ ⊤ = univ := by
rw [← Ioi_inter_Iio]
simp
@[simp]
theorem toReal_coe_ennreal : ∀ {x : ℝ≥0∞}, toReal (x : EReal) = ENNReal.toReal x
| ⊤ => rfl
| .some _ => rfl
#align ereal.to_real_coe_ennreal EReal.toReal_coe_ennreal
@[simp]
theorem coe_ennreal_ofReal {x : ℝ} : (ENNReal.ofReal x : EReal) = max x 0 :=
rfl
#align ereal.coe_ennreal_of_real EReal.coe_ennreal_ofReal
theorem coe_nnreal_eq_coe_real (x : ℝ≥0) : ((x : ℝ≥0∞) : EReal) = (x : ℝ) :=
rfl
#align ereal.coe_nnreal_eq_coe_real EReal.coe_nnreal_eq_coe_real
@[simp, norm_cast]
theorem coe_ennreal_zero : ((0 : ℝ≥0∞) : EReal) = 0 :=
rfl
#align ereal.coe_ennreal_zero EReal.coe_ennreal_zero
@[simp, norm_cast]
theorem coe_ennreal_one : ((1 : ℝ≥0∞) : EReal) = 1 :=
rfl
#align ereal.coe_ennreal_one EReal.coe_ennreal_one
@[simp, norm_cast]
theorem coe_ennreal_top : ((⊤ : ℝ≥0∞) : EReal) = ⊤ :=
rfl
#align ereal.coe_ennreal_top EReal.coe_ennreal_top
theorem coe_ennreal_strictMono : StrictMono ((↑) : ℝ≥0∞ → EReal) :=
WithTop.strictMono_iff.2 ⟨fun _ _ => EReal.coe_lt_coe_iff.2, fun _ => coe_lt_top _⟩
#align ereal.coe_ennreal_strict_mono EReal.coe_ennreal_strictMono
theorem coe_ennreal_injective : Injective ((↑) : ℝ≥0∞ → EReal) :=
coe_ennreal_strictMono.injective
#align ereal.coe_ennreal_injective EReal.coe_ennreal_injective
@[simp]
theorem coe_ennreal_eq_top_iff {x : ℝ≥0∞} : (x : EReal) = ⊤ ↔ x = ⊤ :=
coe_ennreal_injective.eq_iff' rfl
#align ereal.coe_ennreal_eq_top_iff EReal.coe_ennreal_eq_top_iff
theorem coe_nnreal_ne_top (x : ℝ≥0) : ((x : ℝ≥0∞) : EReal) ≠ ⊤ := coe_ne_top x
#align ereal.coe_nnreal_ne_top EReal.coe_nnreal_ne_top
@[simp]
theorem coe_nnreal_lt_top (x : ℝ≥0) : ((x : ℝ≥0∞) : EReal) < ⊤ := coe_lt_top x
#align ereal.coe_nnreal_lt_top EReal.coe_nnreal_lt_top
@[simp, norm_cast]
theorem coe_ennreal_le_coe_ennreal_iff {x y : ℝ≥0∞} : (x : EReal) ≤ (y : EReal) ↔ x ≤ y :=
coe_ennreal_strictMono.le_iff_le
#align ereal.coe_ennreal_le_coe_ennreal_iff EReal.coe_ennreal_le_coe_ennreal_iff
@[simp, norm_cast]
theorem coe_ennreal_lt_coe_ennreal_iff {x y : ℝ≥0∞} : (x : EReal) < (y : EReal) ↔ x < y :=
coe_ennreal_strictMono.lt_iff_lt
#align ereal.coe_ennreal_lt_coe_ennreal_iff EReal.coe_ennreal_lt_coe_ennreal_iff
@[simp, norm_cast]
theorem coe_ennreal_eq_coe_ennreal_iff {x y : ℝ≥0∞} : (x : EReal) = (y : EReal) ↔ x = y :=
coe_ennreal_injective.eq_iff
#align ereal.coe_ennreal_eq_coe_ennreal_iff EReal.coe_ennreal_eq_coe_ennreal_iff
theorem coe_ennreal_ne_coe_ennreal_iff {x y : ℝ≥0∞} : (x : EReal) ≠ (y : EReal) ↔ x ≠ y :=
coe_ennreal_injective.ne_iff
#align ereal.coe_ennreal_ne_coe_ennreal_iff EReal.coe_ennreal_ne_coe_ennreal_iff
@[simp, norm_cast]
theorem coe_ennreal_eq_zero {x : ℝ≥0∞} : (x : EReal) = 0 ↔ x = 0 := by
rw [← coe_ennreal_eq_coe_ennreal_iff, coe_ennreal_zero]
#align ereal.coe_ennreal_eq_zero EReal.coe_ennreal_eq_zero
@[simp, norm_cast]
theorem coe_ennreal_eq_one {x : ℝ≥0∞} : (x : EReal) = 1 ↔ x = 1 := by
rw [← coe_ennreal_eq_coe_ennreal_iff, coe_ennreal_one]
#align ereal.coe_ennreal_eq_one EReal.coe_ennreal_eq_one
@[norm_cast]
theorem coe_ennreal_ne_zero {x : ℝ≥0∞} : (x : EReal) ≠ 0 ↔ x ≠ 0 :=
coe_ennreal_eq_zero.not
#align ereal.coe_ennreal_ne_zero EReal.coe_ennreal_ne_zero
@[norm_cast]
theorem coe_ennreal_ne_one {x : ℝ≥0∞} : (x : EReal) ≠ 1 ↔ x ≠ 1 :=
coe_ennreal_eq_one.not
#align ereal.coe_ennreal_ne_one EReal.coe_ennreal_ne_one
theorem coe_ennreal_nonneg (x : ℝ≥0∞) : (0 : EReal) ≤ x :=
coe_ennreal_le_coe_ennreal_iff.2 (zero_le x)
#align ereal.coe_ennreal_nonneg EReal.coe_ennreal_nonneg
@[simp] theorem range_coe_ennreal : range ((↑) : ℝ≥0∞ → EReal) = Set.Ici 0 :=
Subset.antisymm (range_subset_iff.2 coe_ennreal_nonneg) fun x => match x with
| ⊥ => fun h => absurd h bot_lt_zero.not_le
| ⊤ => fun _ => ⟨⊤, rfl⟩
| (x : ℝ) => fun h => ⟨.some ⟨x, EReal.coe_nonneg.1 h⟩, rfl⟩
instance : CanLift EReal ℝ≥0∞ (↑) (0 ≤ ·) := ⟨range_coe_ennreal.ge⟩
@[simp, norm_cast]
theorem coe_ennreal_pos {x : ℝ≥0∞} : (0 : EReal) < x ↔ 0 < x := by
rw [← coe_ennreal_zero, coe_ennreal_lt_coe_ennreal_iff]
#align ereal.coe_ennreal_pos EReal.coe_ennreal_pos
@[simp]
theorem bot_lt_coe_ennreal (x : ℝ≥0∞) : (⊥ : EReal) < x :=
(bot_lt_coe 0).trans_le (coe_ennreal_nonneg _)
#align ereal.bot_lt_coe_ennreal EReal.bot_lt_coe_ennreal
@[simp]
theorem coe_ennreal_ne_bot (x : ℝ≥0∞) : (x : EReal) ≠ ⊥ :=
(bot_lt_coe_ennreal x).ne'
#align ereal.coe_ennreal_ne_bot EReal.coe_ennreal_ne_bot
@[simp, norm_cast]
theorem coe_ennreal_add (x y : ENNReal) : ((x + y : ℝ≥0∞) : EReal) = x + y := by
cases x <;> cases y <;> rfl
#align ereal.coe_ennreal_add EReal.coe_ennreal_add
private theorem coe_ennreal_top_mul (x : ℝ≥0) : ((⊤ * x : ℝ≥0∞) : EReal) = ⊤ * x := by
rcases eq_or_ne x 0 with (rfl | h0)
· simp
· rw [ENNReal.top_mul (ENNReal.coe_ne_zero.2 h0)]
exact Eq.symm <| if_pos <| NNReal.coe_pos.2 h0.bot_lt
@[simp, norm_cast]
theorem coe_ennreal_mul : ∀ x y : ℝ≥0∞, ((x * y : ℝ≥0∞) : EReal) = (x : EReal) * y
| ⊤, ⊤ => rfl
| ⊤, (y : ℝ≥0) => coe_ennreal_top_mul y
| (x : ℝ≥0), ⊤ => by
rw [mul_comm, coe_ennreal_top_mul, EReal.mul_comm, coe_ennreal_top]
| (x : ℝ≥0), (y : ℝ≥0) => by
simp only [← ENNReal.coe_mul, coe_nnreal_eq_coe_real, NNReal.coe_mul, EReal.coe_mul]
#align ereal.coe_ennreal_mul EReal.coe_ennreal_mul
@[norm_cast]
theorem coe_ennreal_nsmul (n : ℕ) (x : ℝ≥0∞) : (↑(n • x) : EReal) = n • (x : EReal) :=
map_nsmul (⟨⟨(↑), coe_ennreal_zero⟩, coe_ennreal_add⟩ : ℝ≥0∞ →+ EReal) _ _
#align ereal.coe_ennreal_nsmul EReal.coe_ennreal_nsmul
#noalign ereal.coe_ennreal_bit0
#noalign ereal.coe_ennreal_bit1
theorem exists_rat_btwn_of_lt :
∀ {a b : EReal}, a < b → ∃ x : ℚ, a < (x : ℝ) ∧ ((x : ℝ) : EReal) < b
| ⊤, b, h => (not_top_lt h).elim
| (a : ℝ), ⊥, h => (lt_irrefl _ ((bot_lt_coe a).trans h)).elim
| (a : ℝ), (b : ℝ), h => by simp [exists_rat_btwn (EReal.coe_lt_coe_iff.1 h)]
| (a : ℝ), ⊤, _ =>
let ⟨b, hab⟩ := exists_rat_gt a
⟨b, by simpa using hab, coe_lt_top _⟩
| ⊥, ⊥, h => (lt_irrefl _ h).elim
| ⊥, (a : ℝ), _ =>
let ⟨b, hab⟩ := exists_rat_lt a
⟨b, bot_lt_coe _, by simpa using hab⟩
| ⊥, ⊤, _ => ⟨0, bot_lt_coe _, coe_lt_top _⟩
#align ereal.exists_rat_btwn_of_lt EReal.exists_rat_btwn_of_lt
theorem lt_iff_exists_rat_btwn {a b : EReal} :
a < b ↔ ∃ x : ℚ, a < (x : ℝ) ∧ ((x : ℝ) : EReal) < b :=
⟨fun hab => exists_rat_btwn_of_lt hab, fun ⟨_x, ax, xb⟩ => ax.trans xb⟩
#align ereal.lt_iff_exists_rat_btwn EReal.lt_iff_exists_rat_btwn
theorem lt_iff_exists_real_btwn {a b : EReal} : a < b ↔ ∃ x : ℝ, a < x ∧ (x : EReal) < b :=
⟨fun hab =>
let ⟨x, ax, xb⟩ := exists_rat_btwn_of_lt hab
⟨(x : ℝ), ax, xb⟩,
fun ⟨_x, ax, xb⟩ => ax.trans xb⟩
#align ereal.lt_iff_exists_real_btwn EReal.lt_iff_exists_real_btwn
def neTopBotEquivReal : ({⊥, ⊤}ᶜ : Set EReal) ≃ ℝ where
toFun x := EReal.toReal x
invFun x := ⟨x, by simp⟩
left_inv := fun ⟨x, hx⟩ => by
lift x to ℝ
· simpa [not_or, and_comm] using hx
· simp
right_inv x := by simp
#align ereal.ne_top_bot_equiv_real EReal.neTopBotEquivReal
@[simp]
theorem add_bot (x : EReal) : x + ⊥ = ⊥ :=
WithBot.add_bot _
#align ereal.add_bot EReal.add_bot
@[simp]
theorem bot_add (x : EReal) : ⊥ + x = ⊥ :=
WithBot.bot_add _
#align ereal.bot_add EReal.bot_add
@[simp]
theorem add_eq_bot_iff {x y : EReal} : x + y = ⊥ ↔ x = ⊥ ∨ y = ⊥ :=
WithBot.add_eq_bot
#align ereal.add_eq_bot_iff EReal.add_eq_bot_iff
@[simp]
theorem bot_lt_add_iff {x y : EReal} : ⊥ < x + y ↔ ⊥ < x ∧ ⊥ < y := by
simp [bot_lt_iff_ne_bot, not_or]
#align ereal.bot_lt_add_iff EReal.bot_lt_add_iff
@[simp]
theorem top_add_top : (⊤ : EReal) + ⊤ = ⊤ :=
rfl
#align ereal.top_add_top EReal.top_add_top
@[simp]
theorem top_add_coe (x : ℝ) : (⊤ : EReal) + x = ⊤ :=
rfl
#align ereal.top_add_coe EReal.top_add_coe
@[simp]
theorem coe_add_top (x : ℝ) : (x : EReal) + ⊤ = ⊤ :=
rfl
#align ereal.coe_add_top EReal.coe_add_top
theorem toReal_add {x y : EReal} (hx : x ≠ ⊤) (h'x : x ≠ ⊥) (hy : y ≠ ⊤) (h'y : y ≠ ⊥) :
toReal (x + y) = toReal x + toReal y := by
lift x to ℝ using ⟨hx, h'x⟩
lift y to ℝ using ⟨hy, h'y⟩
rfl
#align ereal.to_real_add EReal.toReal_add
theorem addLECancellable_coe (x : ℝ) : AddLECancellable (x : EReal)
| _, ⊤, _ => le_top
| ⊥, _, _ => bot_le
| ⊤, (z : ℝ), h => by simp only [coe_add_top, ← coe_add, top_le_iff, coe_ne_top] at h
| _, ⊥, h => by simpa using h
| (y : ℝ), (z : ℝ), h => by
simpa only [← coe_add, EReal.coe_le_coe_iff, add_le_add_iff_left] using h
-- Porting note (#11215): TODO: add `MulLECancellable.strictMono*` etc
theorem add_lt_add_right_coe {x y : EReal} (h : x < y) (z : ℝ) : x + z < y + z :=
not_le.1 <| mt (addLECancellable_coe z).add_le_add_iff_right.1 h.not_le
#align ereal.add_lt_add_right_coe EReal.add_lt_add_right_coe
theorem add_lt_add_left_coe {x y : EReal} (h : x < y) (z : ℝ) : (z : EReal) + x < z + y := by
simpa [add_comm] using add_lt_add_right_coe h z
#align ereal.add_lt_add_left_coe EReal.add_lt_add_left_coe
theorem add_lt_add {x y z t : EReal} (h1 : x < y) (h2 : z < t) : x + z < y + t := by
rcases eq_or_ne x ⊥ with (rfl | hx)
· simp [h1, bot_le.trans_lt h2]
· lift x to ℝ using ⟨h1.ne_top, hx⟩
calc (x : EReal) + z < x + t := add_lt_add_left_coe h2 _
_ ≤ y + t := add_le_add_right h1.le _
#align ereal.add_lt_add EReal.add_lt_add
theorem add_lt_add_of_lt_of_le' {x y z t : EReal} (h : x < y) (h' : z ≤ t) (hbot : t ≠ ⊥)
(htop : t = ⊤ → z = ⊤ → x = ⊥) : x + z < y + t := by
rcases h'.eq_or_lt with (rfl | hlt)
· rcases eq_or_ne z ⊤ with (rfl | hz)
· obtain rfl := htop rfl rfl
simpa
lift z to ℝ using ⟨hz, hbot⟩
exact add_lt_add_right_coe h z
· exact add_lt_add h hlt
theorem add_lt_add_of_lt_of_le {x y z t : EReal} (h : x < y) (h' : z ≤ t) (hz : z ≠ ⊥)
(ht : t ≠ ⊤) : x + z < y + t :=
add_lt_add_of_lt_of_le' h h' (ne_bot_of_le_ne_bot hz h') fun ht' => (ht ht').elim
#align ereal.add_lt_add_of_lt_of_le EReal.add_lt_add_of_lt_of_le
theorem add_lt_top {x y : EReal} (hx : x ≠ ⊤) (hy : y ≠ ⊤) : x + y < ⊤ := by
rw [← EReal.top_add_top]
exact EReal.add_lt_add hx.lt_top hy.lt_top
#align ereal.add_lt_top EReal.add_lt_top
instance : LinearOrderedAddCommMonoidWithTop ERealᵒᵈ where
le_top := by simp
top_add' := by
rw [OrderDual.forall]
intro x
rw [← OrderDual.toDual_bot, ← toDual_add, bot_add, OrderDual.toDual_bot]
protected def neg : EReal → EReal
| ⊥ => ⊤
| ⊤ => ⊥
| (x : ℝ) => (-x : ℝ)
#align ereal.neg EReal.neg
instance : Neg EReal := ⟨EReal.neg⟩
instance : SubNegZeroMonoid EReal where
neg_zero := congr_arg Real.toEReal neg_zero
zsmul := zsmulRec
@[simp]
theorem neg_top : -(⊤ : EReal) = ⊥ :=
rfl
#align ereal.neg_top EReal.neg_top
@[simp]
theorem neg_bot : -(⊥ : EReal) = ⊤ :=
rfl
#align ereal.neg_bot EReal.neg_bot
@[simp, norm_cast] theorem coe_neg (x : ℝ) : (↑(-x) : EReal) = -↑x := rfl
#align ereal.coe_neg EReal.coe_neg
#align ereal.neg_def EReal.coe_neg
@[simp, norm_cast] theorem coe_sub (x y : ℝ) : (↑(x - y) : EReal) = x - y := rfl
#align ereal.coe_sub EReal.coe_sub
@[norm_cast]
theorem coe_zsmul (n : ℤ) (x : ℝ) : (↑(n • x) : EReal) = n • (x : EReal) :=
map_zsmul' (⟨⟨(↑), coe_zero⟩, coe_add⟩ : ℝ →+ EReal) coe_neg _ _
#align ereal.coe_zsmul EReal.coe_zsmul
instance : InvolutiveNeg EReal where
neg_neg a :=
match a with
| ⊥ => rfl
| ⊤ => rfl
| (a : ℝ) => congr_arg Real.toEReal (neg_neg a)
@[simp]
theorem toReal_neg : ∀ {a : EReal}, toReal (-a) = -toReal a
| ⊤ => by simp
| ⊥ => by simp
| (x : ℝ) => rfl
#align ereal.to_real_neg EReal.toReal_neg
@[simp]
theorem neg_eq_top_iff {x : EReal} : -x = ⊤ ↔ x = ⊥ :=
neg_injective.eq_iff' rfl
#align ereal.neg_eq_top_iff EReal.neg_eq_top_iff
@[simp]
theorem neg_eq_bot_iff {x : EReal} : -x = ⊥ ↔ x = ⊤ :=
neg_injective.eq_iff' rfl
#align ereal.neg_eq_bot_iff EReal.neg_eq_bot_iff
@[simp]
theorem neg_eq_zero_iff {x : EReal} : -x = 0 ↔ x = 0 :=
neg_injective.eq_iff' neg_zero
#align ereal.neg_eq_zero_iff EReal.neg_eq_zero_iff
theorem neg_strictAnti : StrictAnti (- · : EReal → EReal) :=
WithBot.strictAnti_iff.2 ⟨WithTop.strictAnti_iff.2
⟨coe_strictMono.comp_strictAnti fun _ _ => neg_lt_neg, fun _ => bot_lt_coe _⟩,
WithTop.forall.2 ⟨bot_lt_top, fun _ => coe_lt_top _⟩⟩
@[simp] theorem neg_le_neg_iff {a b : EReal} : -a ≤ -b ↔ b ≤ a := neg_strictAnti.le_iff_le
#align ereal.neg_le_neg_iff EReal.neg_le_neg_iff
-- Porting note (#10756): new lemma
@[simp] theorem neg_lt_neg_iff {a b : EReal} : -a < -b ↔ b < a := neg_strictAnti.lt_iff_lt
protected theorem neg_le {a b : EReal} : -a ≤ b ↔ -b ≤ a := by
rw [← neg_le_neg_iff, neg_neg]
#align ereal.neg_le EReal.neg_le
protected theorem neg_le_of_neg_le {a b : EReal} (h : -a ≤ b) : -b ≤ a := EReal.neg_le.mp h
#align ereal.neg_le_of_neg_le EReal.neg_le_of_neg_le
theorem le_neg_of_le_neg {a b : EReal} (h : a ≤ -b) : b ≤ -a := by
rwa [← neg_neg b, EReal.neg_le, neg_neg]
#align ereal.le_neg_of_le_neg EReal.le_neg_of_le_neg
def negOrderIso : EReal ≃o ERealᵒᵈ :=
{ Equiv.neg EReal with
toFun := fun x => OrderDual.toDual (-x)
invFun := fun x => -OrderDual.ofDual x
map_rel_iff' := neg_le_neg_iff }
#align ereal.neg_order_iso EReal.negOrderIso
theorem neg_lt_iff_neg_lt {a b : EReal} : -a < b ↔ -b < a := by
rw [← neg_lt_neg_iff, neg_neg]
#align ereal.neg_lt_iff_neg_lt EReal.neg_lt_iff_neg_lt
theorem neg_lt_of_neg_lt {a b : EReal} (h : -a < b) : -b < a := neg_lt_iff_neg_lt.1 h
#align ereal.neg_lt_of_neg_lt EReal.neg_lt_of_neg_lt
@[simp]
theorem bot_sub (x : EReal) : ⊥ - x = ⊥ :=
bot_add x
#align ereal.bot_sub EReal.bot_sub
@[simp]
theorem sub_top (x : EReal) : x - ⊤ = ⊥ :=
add_bot x
#align ereal.sub_top EReal.sub_top
@[simp]
theorem top_sub_bot : (⊤ : EReal) - ⊥ = ⊤ :=
rfl
#align ereal.top_sub_bot EReal.top_sub_bot
@[simp]
theorem top_sub_coe (x : ℝ) : (⊤ : EReal) - x = ⊤ :=
rfl
#align ereal.top_sub_coe EReal.top_sub_coe
@[simp]
theorem coe_sub_bot (x : ℝ) : (x : EReal) - ⊥ = ⊤ :=
rfl
#align ereal.coe_sub_bot EReal.coe_sub_bot
theorem sub_le_sub {x y z t : EReal} (h : x ≤ y) (h' : t ≤ z) : x - z ≤ y - t :=
add_le_add h (neg_le_neg_iff.2 h')
#align ereal.sub_le_sub EReal.sub_le_sub
theorem sub_lt_sub_of_lt_of_le {x y z t : EReal} (h : x < y) (h' : z ≤ t) (hz : z ≠ ⊥)
(ht : t ≠ ⊤) : x - t < y - z :=
add_lt_add_of_lt_of_le h (neg_le_neg_iff.2 h') (by simp [ht]) (by simp [hz])
#align ereal.sub_lt_sub_of_lt_of_le EReal.sub_lt_sub_of_lt_of_le
theorem coe_real_ereal_eq_coe_toNNReal_sub_coe_toNNReal (x : ℝ) :
(x : EReal) = Real.toNNReal x - Real.toNNReal (-x) := by
rcases le_total 0 x with (h | h)
· lift x to ℝ≥0 using h
rw [Real.toNNReal_of_nonpos (neg_nonpos.mpr x.coe_nonneg), Real.toNNReal_coe, ENNReal.coe_zero,
coe_ennreal_zero, sub_zero]
rfl
· rw [Real.toNNReal_of_nonpos h, ENNReal.coe_zero, coe_ennreal_zero, coe_nnreal_eq_coe_real,
Real.coe_toNNReal, zero_sub, coe_neg, neg_neg]
exact neg_nonneg.2 h
#align ereal.coe_real_ereal_eq_coe_to_nnreal_sub_coe_to_nnreal EReal.coe_real_ereal_eq_coe_toNNReal_sub_coe_toNNReal
theorem toReal_sub {x y : EReal} (hx : x ≠ ⊤) (h'x : x ≠ ⊥) (hy : y ≠ ⊤) (h'y : y ≠ ⊥) :
toReal (x - y) = toReal x - toReal y := by
lift x to ℝ using ⟨hx, h'x⟩
lift y to ℝ using ⟨hy, h'y⟩
rfl
#align ereal.to_real_sub EReal.toReal_sub
@[simp] theorem top_mul_top : (⊤ : EReal) * ⊤ = ⊤ := rfl
#align ereal.top_mul_top EReal.top_mul_top
@[simp] theorem top_mul_bot : (⊤ : EReal) * ⊥ = ⊥ := rfl
#align ereal.top_mul_bot EReal.top_mul_bot
@[simp] theorem bot_mul_top : (⊥ : EReal) * ⊤ = ⊥ := rfl
#align ereal.bot_mul_top EReal.bot_mul_top
@[simp] theorem bot_mul_bot : (⊥ : EReal) * ⊥ = ⊤ := rfl
#align ereal.bot_mul_bot EReal.bot_mul_bot
theorem coe_mul_top_of_pos {x : ℝ} (h : 0 < x) : (x : EReal) * ⊤ = ⊤ :=
if_pos h
#align ereal.coe_mul_top_of_pos EReal.coe_mul_top_of_pos
theorem coe_mul_top_of_neg {x : ℝ} (h : x < 0) : (x : EReal) * ⊤ = ⊥ :=
(if_neg h.not_lt).trans (if_neg h.ne)
#align ereal.coe_mul_top_of_neg EReal.coe_mul_top_of_neg
theorem top_mul_coe_of_pos {x : ℝ} (h : 0 < x) : (⊤ : EReal) * x = ⊤ :=
if_pos h
#align ereal.top_mul_coe_of_pos EReal.top_mul_coe_of_pos
theorem top_mul_coe_of_neg {x : ℝ} (h : x < 0) : (⊤ : EReal) * x = ⊥ :=
(if_neg h.not_lt).trans (if_neg h.ne)
#align ereal.top_mul_coe_of_neg EReal.top_mul_coe_of_neg
theorem mul_top_of_pos : ∀ {x : EReal}, 0 < x → x * ⊤ = ⊤
| ⊥, h => absurd h not_lt_bot
| (x : ℝ), h => coe_mul_top_of_pos (EReal.coe_pos.1 h)
| ⊤, _ => rfl
#align ereal.mul_top_of_pos EReal.mul_top_of_pos
theorem mul_top_of_neg : ∀ {x : EReal}, x < 0 → x * ⊤ = ⊥
| ⊥, _ => rfl
| (x : ℝ), h => coe_mul_top_of_neg (EReal.coe_neg'.1 h)
| ⊤, h => absurd h not_top_lt
#align ereal.mul_top_of_neg EReal.mul_top_of_neg
theorem top_mul_of_pos {x : EReal} (h : 0 < x) : ⊤ * x = ⊤ := by
rw [EReal.mul_comm]
exact mul_top_of_pos h
#align ereal.top_mul_of_pos EReal.top_mul_of_pos
theorem top_mul_of_neg {x : EReal} (h : x < 0) : ⊤ * x = ⊥ := by
rw [EReal.mul_comm]
exact mul_top_of_neg h
#align ereal.top_mul_of_neg EReal.top_mul_of_neg
theorem coe_mul_bot_of_pos {x : ℝ} (h : 0 < x) : (x : EReal) * ⊥ = ⊥ :=
if_pos h
#align ereal.coe_mul_bot_of_pos EReal.coe_mul_bot_of_pos
theorem coe_mul_bot_of_neg {x : ℝ} (h : x < 0) : (x : EReal) * ⊥ = ⊤ :=
(if_neg h.not_lt).trans (if_neg h.ne)
#align ereal.coe_mul_bot_of_neg EReal.coe_mul_bot_of_neg
theorem bot_mul_coe_of_pos {x : ℝ} (h : 0 < x) : (⊥ : EReal) * x = ⊥ :=
if_pos h
#align ereal.bot_mul_coe_of_pos EReal.bot_mul_coe_of_pos
theorem bot_mul_coe_of_neg {x : ℝ} (h : x < 0) : (⊥ : EReal) * x = ⊤ :=
(if_neg h.not_lt).trans (if_neg h.ne)
#align ereal.bot_mul_coe_of_neg EReal.bot_mul_coe_of_neg
theorem mul_bot_of_pos : ∀ {x : EReal}, 0 < x → x * ⊥ = ⊥
| ⊥, h => absurd h not_lt_bot
| (x : ℝ), h => coe_mul_bot_of_pos (EReal.coe_pos.1 h)
| ⊤, _ => rfl
#align ereal.mul_bot_of_pos EReal.mul_bot_of_pos
theorem mul_bot_of_neg : ∀ {x : EReal}, x < 0 → x * ⊥ = ⊤
| ⊥, _ => rfl
| (x : ℝ), h => coe_mul_bot_of_neg (EReal.coe_neg'.1 h)
| ⊤, h => absurd h not_top_lt
#align ereal.mul_bot_of_neg EReal.mul_bot_of_neg
theorem bot_mul_of_pos {x : EReal} (h : 0 < x) : ⊥ * x = ⊥ := by
rw [EReal.mul_comm]
exact mul_bot_of_pos h
#align ereal.bot_mul_of_pos EReal.bot_mul_of_pos
theorem bot_mul_of_neg {x : EReal} (h : x < 0) : ⊥ * x = ⊤ := by
rw [EReal.mul_comm]
exact mul_bot_of_neg h
#align ereal.bot_mul_of_neg EReal.bot_mul_of_neg
theorem toReal_mul {x y : EReal} : toReal (x * y) = toReal x * toReal y := by
induction x, y using induction₂_symm with
| top_zero | zero_bot | top_top | top_bot | bot_bot => simp
| symm h => rwa [mul_comm, EReal.mul_comm]
| coe_coe => norm_cast
| top_pos _ h => simp [top_mul_coe_of_pos h]
| top_neg _ h => simp [top_mul_coe_of_neg h]
| pos_bot _ h => simp [coe_mul_bot_of_pos h]
| neg_bot _ h => simp [coe_mul_bot_of_neg h]
#align ereal.to_real_mul EReal.toReal_mul
@[elab_as_elim]
theorem induction₂_neg_left {P : EReal → EReal → Prop} (neg_left : ∀ {x y}, P x y → P (-x) y)
(top_top : P ⊤ ⊤) (top_pos : ∀ x : ℝ, 0 < x → P ⊤ x)
(top_zero : P ⊤ 0) (top_neg : ∀ x : ℝ, x < 0 → P ⊤ x) (top_bot : P ⊤ ⊥)
(zero_top : P 0 ⊤) (zero_bot : P 0 ⊥)
(pos_top : ∀ x : ℝ, 0 < x → P x ⊤) (pos_bot : ∀ x : ℝ, 0 < x → P x ⊥)
(coe_coe : ∀ x y : ℝ, P x y) : ∀ x y, P x y :=
have : ∀ y, (∀ x : ℝ, 0 < x → P x y) → ∀ x : ℝ, x < 0 → P x y := fun _ h x hx =>
neg_neg (x : EReal) ▸ neg_left <| h _ (neg_pos_of_neg hx)
@induction₂ P top_top top_pos top_zero top_neg top_bot pos_top pos_bot zero_top
coe_coe zero_bot (this _ pos_top) (this _ pos_bot) (neg_left top_top)
(fun x hx => neg_left <| top_pos x hx) (neg_left top_zero)
(fun x hx => neg_left <| top_neg x hx) (neg_left top_bot)
@[elab_as_elim]
theorem induction₂_symm_neg {P : EReal → EReal → Prop}
(symm : ∀ {x y}, P x y → P y x)
(neg_left : ∀ {x y}, P x y → P (-x) y) (top_top : P ⊤ ⊤)
(top_pos : ∀ x : ℝ, 0 < x → P ⊤ x) (top_zero : P ⊤ 0) (coe_coe : ∀ x y : ℝ, P x y) :
∀ x y, P x y :=
have neg_right : ∀ {x y}, P x y → P x (-y) := fun h => symm <| neg_left <| symm h
have : ∀ x, (∀ y : ℝ, 0 < y → P x y) → ∀ y : ℝ, y < 0 → P x y := fun _ h y hy =>
neg_neg (y : EReal) ▸ neg_right (h _ (neg_pos_of_neg hy))
@induction₂_neg_left P neg_left top_top top_pos top_zero (this _ top_pos) (neg_right top_top)
(symm top_zero) (symm <| neg_left top_zero) (fun x hx => symm <| top_pos x hx)
(fun x hx => symm <| neg_left <| top_pos x hx) coe_coe
protected theorem neg_mul (x y : EReal) : -x * y = -(x * y) := by
induction x, y using induction₂_neg_left with
| top_zero | zero_top | zero_bot => simp only [zero_mul, mul_zero, neg_zero]
| top_top | top_bot => rfl
| neg_left h => rw [h, neg_neg, neg_neg]
| coe_coe => norm_cast; exact neg_mul _ _
| top_pos _ h => rw [top_mul_coe_of_pos h, neg_top, bot_mul_coe_of_pos h]
| pos_top _ h => rw [coe_mul_top_of_pos h, neg_top, ← coe_neg,
coe_mul_top_of_neg (neg_neg_of_pos h)]
| top_neg _ h => rw [top_mul_coe_of_neg h, neg_top, bot_mul_coe_of_neg h, neg_bot]
| pos_bot _ h => rw [coe_mul_bot_of_pos h, neg_bot, ← coe_neg,
coe_mul_bot_of_neg (neg_neg_of_pos h)]
#align ereal.neg_mul EReal.neg_mul
instance : HasDistribNeg EReal where
neg_mul := EReal.neg_mul
mul_neg := fun x y => by
rw [x.mul_comm, x.mul_comm]
exact y.neg_mul x
-- Porting note (#11215): TODO: use `Real.nnabs` for the case `(x : ℝ)`
protected def abs : EReal → ℝ≥0∞
| ⊥ => ⊤
| ⊤ => ⊤
| (x : ℝ) => ENNReal.ofReal |x|
#align ereal.abs EReal.abs
@[simp] theorem abs_top : (⊤ : EReal).abs = ⊤ := rfl
#align ereal.abs_top EReal.abs_top
@[simp] theorem abs_bot : (⊥ : EReal).abs = ⊤ := rfl
#align ereal.abs_bot EReal.abs_bot
theorem abs_def (x : ℝ) : (x : EReal).abs = ENNReal.ofReal |x| := rfl
#align ereal.abs_def EReal.abs_def
theorem abs_coe_lt_top (x : ℝ) : (x : EReal).abs < ⊤ :=
ENNReal.ofReal_lt_top
#align ereal.abs_coe_lt_top EReal.abs_coe_lt_top
@[simp]
theorem abs_eq_zero_iff {x : EReal} : x.abs = 0 ↔ x = 0 := by
induction x
· simp only [abs_bot, ENNReal.top_ne_zero, bot_ne_zero]
· simp only [abs_def, coe_eq_zero, ENNReal.ofReal_eq_zero, abs_nonpos_iff]
· simp only [abs_top, ENNReal.top_ne_zero, top_ne_zero]
#align ereal.abs_eq_zero_iff EReal.abs_eq_zero_iff
@[simp]
theorem abs_zero : (0 : EReal).abs = 0 := by rw [abs_eq_zero_iff]
#align ereal.abs_zero EReal.abs_zero
@[simp]
theorem coe_abs (x : ℝ) : ((x : EReal).abs : EReal) = (|x| : ℝ) := by
rw [abs_def, ← Real.coe_nnabs, ENNReal.ofReal_coe_nnreal]; rfl
#align ereal.coe_abs EReal.coe_abs
@[simp]
protected theorem abs_neg : ∀ x : EReal, (-x).abs = x.abs
| ⊤ => rfl
| ⊥ => rfl
| (x : ℝ) => by rw [abs_def, ← coe_neg, abs_def, abs_neg]
@[simp]
theorem abs_mul (x y : EReal) : (x * y).abs = x.abs * y.abs := by
induction x, y using induction₂_symm_neg with
| top_zero => simp only [zero_mul, mul_zero, abs_zero]
| top_top => rfl
| symm h => rwa [mul_comm, EReal.mul_comm]
| coe_coe => simp only [← coe_mul, abs_def, _root_.abs_mul, ENNReal.ofReal_mul (abs_nonneg _)]
| top_pos _ h =>
rw [top_mul_coe_of_pos h, abs_top, ENNReal.top_mul]
rw [Ne, abs_eq_zero_iff, coe_eq_zero]
exact h.ne'
| neg_left h => rwa [neg_mul, EReal.abs_neg, EReal.abs_neg]
#align ereal.abs_mul EReal.abs_mul
open SignType (sign)
theorem sign_top : sign (⊤ : EReal) = 1 := rfl
#align ereal.sign_top EReal.sign_top
theorem sign_bot : sign (⊥ : EReal) = -1 := rfl
#align ereal.sign_bot EReal.sign_bot
@[simp]
theorem sign_coe (x : ℝ) : sign (x : EReal) = sign x := by
simp only [sign, OrderHom.coe_mk, EReal.coe_pos, EReal.coe_neg']
#align ereal.sign_coe EReal.sign_coe
@[simp, norm_cast]
theorem coe_coe_sign (x : SignType) : ((x : ℝ) : EReal) = x := by cases x <;> rfl
@[simp] theorem sign_neg : ∀ x : EReal, sign (-x) = -sign x
| ⊤ => rfl
| ⊥ => rfl
| (x : ℝ) => by rw [← coe_neg, sign_coe, sign_coe, Left.sign_neg]
@[simp]
theorem sign_mul (x y : EReal) : sign (x * y) = sign x * sign y := by
induction x, y using induction₂_symm_neg with
| top_zero => simp only [zero_mul, mul_zero, sign_zero]
| top_top => rfl
| symm h => rwa [mul_comm, EReal.mul_comm]
| coe_coe => simp only [← coe_mul, sign_coe, _root_.sign_mul, ENNReal.ofReal_mul (abs_nonneg _)]
| top_pos _ h =>
rw [top_mul_coe_of_pos h, sign_top, one_mul, sign_pos (EReal.coe_pos.2 h)]
| neg_left h => rw [neg_mul, sign_neg, sign_neg, h, neg_mul]
#align ereal.sign_mul EReal.sign_mul
@[simp] protected theorem sign_mul_abs : ∀ x : EReal, (sign x * x.abs : EReal) = x
| ⊥ => by simp
| ⊤ => by simp
| (x : ℝ) => by rw [sign_coe, coe_abs, ← coe_coe_sign, ← coe_mul, sign_mul_abs]
#align ereal.sign_mul_abs EReal.sign_mul_abs
@[simp] protected theorem abs_mul_sign (x : EReal) : (x.abs * sign x : EReal) = x := by
rw [EReal.mul_comm, EReal.sign_mul_abs]
| Mathlib/Data/Real/EReal.lean | 1,297 | 1,303 | theorem sign_eq_and_abs_eq_iff_eq {x y : EReal} :
x.abs = y.abs ∧ sign x = sign y ↔ x = y := by |
constructor
· rintro ⟨habs, hsign⟩
rw [← x.sign_mul_abs, ← y.sign_mul_abs, habs, hsign]
· rintro rfl
exact ⟨rfl, rfl⟩
|
import Mathlib.Algebra.MvPolynomial.Expand
import Mathlib.FieldTheory.Finite.Basic
import Mathlib.RingTheory.MvPolynomial.Basic
#align_import field_theory.finite.polynomial from "leanprover-community/mathlib"@"5aa3c1de9f3c642eac76e11071c852766f220fd0"
namespace MvPolynomial
variable {σ : Type*}
theorem C_dvd_iff_zmod (n : ℕ) (φ : MvPolynomial σ ℤ) :
C (n : ℤ) ∣ φ ↔ map (Int.castRingHom (ZMod n)) φ = 0 :=
C_dvd_iff_map_hom_eq_zero _ _ (CharP.intCast_eq_zero_iff (ZMod n) n) _
set_option linter.uppercaseLean3 false in
#align mv_polynomial.C_dvd_iff_zmod MvPolynomial.C_dvd_iff_zmod
section frobenius
variable {p : ℕ} [Fact p.Prime]
| Mathlib/FieldTheory/Finite/Polynomial.lean | 33 | 38 | theorem frobenius_zmod (f : MvPolynomial σ (ZMod p)) : frobenius _ p f = expand p f := by |
apply induction_on f
· intro a; rw [expand_C, frobenius_def, ← C_pow, ZMod.pow_card]
· simp only [AlgHom.map_add, RingHom.map_add]; intro _ _ hf hg; rw [hf, hg]
· simp only [expand_X, RingHom.map_mul, AlgHom.map_mul]
intro _ _ hf; rw [hf, frobenius_def]
|
import Mathlib.AlgebraicTopology.SimplexCategory
import Mathlib.CategoryTheory.Comma.Arrow
import Mathlib.CategoryTheory.Limits.FunctorCategory
import Mathlib.CategoryTheory.Opposites
#align_import algebraic_topology.simplicial_object from "leanprover-community/mathlib"@"5ed51dc37c6b891b79314ee11a50adc2b1df6fd6"
open Opposite
open CategoryTheory
open CategoryTheory.Limits
universe v u v' u'
namespace CategoryTheory
variable (C : Type u) [Category.{v} C]
-- porting note (#5171): removed @[nolint has_nonempty_instance]
def SimplicialObject :=
SimplexCategoryᵒᵖ ⥤ C
#align category_theory.simplicial_object CategoryTheory.SimplicialObject
@[simps!]
instance : Category (SimplicialObject C) := by
dsimp only [SimplicialObject]
infer_instance
namespace SimplicialObject
set_option quotPrecheck false in
scoped[Simplicial]
notation3:1000 X " _[" n "]" =>
(X : CategoryTheory.SimplicialObject _).obj (Opposite.op (SimplexCategory.mk n))
open Simplicial
instance {J : Type v} [SmallCategory J] [HasLimitsOfShape J C] :
HasLimitsOfShape J (SimplicialObject C) := by
dsimp [SimplicialObject]
infer_instance
instance [HasLimits C] : HasLimits (SimplicialObject C) :=
⟨inferInstance⟩
instance {J : Type v} [SmallCategory J] [HasColimitsOfShape J C] :
HasColimitsOfShape J (SimplicialObject C) := by
dsimp [SimplicialObject]
infer_instance
instance [HasColimits C] : HasColimits (SimplicialObject C) :=
⟨inferInstance⟩
variable {C}
-- Porting note (#10688): added to ease automation
@[ext]
lemma hom_ext {X Y : SimplicialObject C} (f g : X ⟶ Y)
(h : ∀ (n : SimplexCategoryᵒᵖ), f.app n = g.app n) : f = g :=
NatTrans.ext _ _ (by ext; apply h)
variable (X : SimplicialObject C)
def δ {n} (i : Fin (n + 2)) : X _[n + 1] ⟶ X _[n] :=
X.map (SimplexCategory.δ i).op
#align category_theory.simplicial_object.δ CategoryTheory.SimplicialObject.δ
def σ {n} (i : Fin (n + 1)) : X _[n] ⟶ X _[n + 1] :=
X.map (SimplexCategory.σ i).op
#align category_theory.simplicial_object.σ CategoryTheory.SimplicialObject.σ
def eqToIso {n m : ℕ} (h : n = m) : X _[n] ≅ X _[m] :=
X.mapIso (CategoryTheory.eqToIso (by congr))
#align category_theory.simplicial_object.eq_to_iso CategoryTheory.SimplicialObject.eqToIso
@[simp]
theorem eqToIso_refl {n : ℕ} (h : n = n) : X.eqToIso h = Iso.refl _ := by
ext
simp [eqToIso]
#align category_theory.simplicial_object.eq_to_iso_refl CategoryTheory.SimplicialObject.eqToIso_refl
@[reassoc]
| Mathlib/AlgebraicTopology/SimplicialObject.lean | 107 | 110 | theorem δ_comp_δ {n} {i j : Fin (n + 2)} (H : i ≤ j) :
X.δ j.succ ≫ X.δ i = X.δ (Fin.castSucc i) ≫ X.δ j := by |
dsimp [δ]
simp only [← X.map_comp, ← op_comp, SimplexCategory.δ_comp_δ H]
|
import Mathlib.Algebra.Order.Ring.Nat
import Mathlib.Data.List.Chain
#align_import data.bool.count from "leanprover-community/mathlib"@"8631e2d5ea77f6c13054d9151d82b83069680cb1"
namespace List
@[simp]
theorem count_not_add_count (l : List Bool) (b : Bool) : count (!b) l + count b l = length l := by
-- Porting note: Proof re-written
-- Old proof: simp only [length_eq_countP_add_countP (Eq (!b)), Bool.not_not_eq, count]
simp only [length_eq_countP_add_countP (· == !b), count, add_right_inj]
suffices (fun x => x == b) = (fun a => decide ¬(a == !b) = true) by rw [this]
ext x; cases x <;> cases b <;> rfl
#align list.count_bnot_add_count List.count_not_add_count
@[simp]
| Mathlib/Data/Bool/Count.lean | 33 | 34 | theorem count_add_count_not (l : List Bool) (b : Bool) : count b l + count (!b) l = length l := by |
rw [add_comm, count_not_add_count]
|
import Mathlib.Logic.Relation
import Mathlib.Data.Option.Basic
import Mathlib.Data.Seq.Seq
#align_import data.seq.wseq from "leanprover-community/mathlib"@"a7e36e48519ab281320c4d192da6a7b348ce40ad"
namespace Stream'
open Function
universe u v w
def WSeq (α) :=
Seq (Option α)
#align stream.wseq Stream'.WSeq
namespace WSeq
variable {α : Type u} {β : Type v} {γ : Type w}
@[coe]
def ofSeq : Seq α → WSeq α :=
(· <$> ·) some
#align stream.wseq.of_seq Stream'.WSeq.ofSeq
@[coe]
def ofList (l : List α) : WSeq α :=
ofSeq l
#align stream.wseq.of_list Stream'.WSeq.ofList
@[coe]
def ofStream (l : Stream' α) : WSeq α :=
ofSeq l
#align stream.wseq.of_stream Stream'.WSeq.ofStream
instance coeSeq : Coe (Seq α) (WSeq α) :=
⟨ofSeq⟩
#align stream.wseq.coe_seq Stream'.WSeq.coeSeq
instance coeList : Coe (List α) (WSeq α) :=
⟨ofList⟩
#align stream.wseq.coe_list Stream'.WSeq.coeList
instance coeStream : Coe (Stream' α) (WSeq α) :=
⟨ofStream⟩
#align stream.wseq.coe_stream Stream'.WSeq.coeStream
def nil : WSeq α :=
Seq.nil
#align stream.wseq.nil Stream'.WSeq.nil
instance inhabited : Inhabited (WSeq α) :=
⟨nil⟩
#align stream.wseq.inhabited Stream'.WSeq.inhabited
def cons (a : α) : WSeq α → WSeq α :=
Seq.cons (some a)
#align stream.wseq.cons Stream'.WSeq.cons
def think : WSeq α → WSeq α :=
Seq.cons none
#align stream.wseq.think Stream'.WSeq.think
def destruct : WSeq α → Computation (Option (α × WSeq α)) :=
Computation.corec fun s =>
match Seq.destruct s with
| none => Sum.inl none
| some (none, s') => Sum.inr s'
| some (some a, s') => Sum.inl (some (a, s'))
#align stream.wseq.destruct Stream'.WSeq.destruct
def recOn {C : WSeq α → Sort v} (s : WSeq α) (h1 : C nil) (h2 : ∀ x s, C (cons x s))
(h3 : ∀ s, C (think s)) : C s :=
Seq.recOn s h1 fun o => Option.recOn o h3 h2
#align stream.wseq.rec_on Stream'.WSeq.recOn
protected def Mem (a : α) (s : WSeq α) :=
Seq.Mem (some a) s
#align stream.wseq.mem Stream'.WSeq.Mem
instance membership : Membership α (WSeq α) :=
⟨WSeq.Mem⟩
#align stream.wseq.has_mem Stream'.WSeq.membership
theorem not_mem_nil (a : α) : a ∉ @nil α :=
Seq.not_mem_nil (some a)
#align stream.wseq.not_mem_nil Stream'.WSeq.not_mem_nil
def head (s : WSeq α) : Computation (Option α) :=
Computation.map (Prod.fst <$> ·) (destruct s)
#align stream.wseq.head Stream'.WSeq.head
def flatten : Computation (WSeq α) → WSeq α :=
Seq.corec fun c =>
match Computation.destruct c with
| Sum.inl s => Seq.omap (return ·) (Seq.destruct s)
| Sum.inr c' => some (none, c')
#align stream.wseq.flatten Stream'.WSeq.flatten
def tail (s : WSeq α) : WSeq α :=
flatten <| (fun o => Option.recOn o nil Prod.snd) <$> destruct s
#align stream.wseq.tail Stream'.WSeq.tail
def drop (s : WSeq α) : ℕ → WSeq α
| 0 => s
| n + 1 => tail (drop s n)
#align stream.wseq.drop Stream'.WSeq.drop
def get? (s : WSeq α) (n : ℕ) : Computation (Option α) :=
head (drop s n)
#align stream.wseq.nth Stream'.WSeq.get?
def toList (s : WSeq α) : Computation (List α) :=
@Computation.corec (List α) (List α × WSeq α)
(fun ⟨l, s⟩ =>
match Seq.destruct s with
| none => Sum.inl l.reverse
| some (none, s') => Sum.inr (l, s')
| some (some a, s') => Sum.inr (a::l, s'))
([], s)
#align stream.wseq.to_list Stream'.WSeq.toList
def length (s : WSeq α) : Computation ℕ :=
@Computation.corec ℕ (ℕ × WSeq α)
(fun ⟨n, s⟩ =>
match Seq.destruct s with
| none => Sum.inl n
| some (none, s') => Sum.inr (n, s')
| some (some _, s') => Sum.inr (n + 1, s'))
(0, s)
#align stream.wseq.length Stream'.WSeq.length
class IsFinite (s : WSeq α) : Prop where
out : (toList s).Terminates
#align stream.wseq.is_finite Stream'.WSeq.IsFinite
instance toList_terminates (s : WSeq α) [h : IsFinite s] : (toList s).Terminates :=
h.out
#align stream.wseq.to_list_terminates Stream'.WSeq.toList_terminates
def get (s : WSeq α) [IsFinite s] : List α :=
(toList s).get
#align stream.wseq.get Stream'.WSeq.get
class Productive (s : WSeq α) : Prop where
get?_terminates : ∀ n, (get? s n).Terminates
#align stream.wseq.productive Stream'.WSeq.Productive
#align stream.wseq.productive.nth_terminates Stream'.WSeq.Productive.get?_terminates
theorem productive_iff (s : WSeq α) : Productive s ↔ ∀ n, (get? s n).Terminates :=
⟨fun h => h.1, fun h => ⟨h⟩⟩
#align stream.wseq.productive_iff Stream'.WSeq.productive_iff
instance get?_terminates (s : WSeq α) [h : Productive s] : ∀ n, (get? s n).Terminates :=
h.get?_terminates
#align stream.wseq.nth_terminates Stream'.WSeq.get?_terminates
instance head_terminates (s : WSeq α) [Productive s] : (head s).Terminates :=
s.get?_terminates 0
#align stream.wseq.head_terminates Stream'.WSeq.head_terminates
def updateNth (s : WSeq α) (n : ℕ) (a : α) : WSeq α :=
@Seq.corec (Option α) (ℕ × WSeq α)
(fun ⟨n, s⟩ =>
match Seq.destruct s, n with
| none, _ => none
| some (none, s'), n => some (none, n, s')
| some (some a', s'), 0 => some (some a', 0, s')
| some (some _, s'), 1 => some (some a, 0, s')
| some (some a', s'), n + 2 => some (some a', n + 1, s'))
(n + 1, s)
#align stream.wseq.update_nth Stream'.WSeq.updateNth
def removeNth (s : WSeq α) (n : ℕ) : WSeq α :=
@Seq.corec (Option α) (ℕ × WSeq α)
(fun ⟨n, s⟩ =>
match Seq.destruct s, n with
| none, _ => none
| some (none, s'), n => some (none, n, s')
| some (some a', s'), 0 => some (some a', 0, s')
| some (some _, s'), 1 => some (none, 0, s')
| some (some a', s'), n + 2 => some (some a', n + 1, s'))
(n + 1, s)
#align stream.wseq.remove_nth Stream'.WSeq.removeNth
def filterMap (f : α → Option β) : WSeq α → WSeq β :=
Seq.corec fun s =>
match Seq.destruct s with
| none => none
| some (none, s') => some (none, s')
| some (some a, s') => some (f a, s')
#align stream.wseq.filter_map Stream'.WSeq.filterMap
def filter (p : α → Prop) [DecidablePred p] : WSeq α → WSeq α :=
filterMap fun a => if p a then some a else none
#align stream.wseq.filter Stream'.WSeq.filter
-- example of infinite list manipulations
def find (p : α → Prop) [DecidablePred p] (s : WSeq α) : Computation (Option α) :=
head <| filter p s
#align stream.wseq.find Stream'.WSeq.find
def zipWith (f : α → β → γ) (s1 : WSeq α) (s2 : WSeq β) : WSeq γ :=
@Seq.corec (Option γ) (WSeq α × WSeq β)
(fun ⟨s1, s2⟩ =>
match Seq.destruct s1, Seq.destruct s2 with
| some (none, s1'), some (none, s2') => some (none, s1', s2')
| some (some _, _), some (none, s2') => some (none, s1, s2')
| some (none, s1'), some (some _, _) => some (none, s1', s2)
| some (some a1, s1'), some (some a2, s2') => some (some (f a1 a2), s1', s2')
| _, _ => none)
(s1, s2)
#align stream.wseq.zip_with Stream'.WSeq.zipWith
def zip : WSeq α → WSeq β → WSeq (α × β) :=
zipWith Prod.mk
#align stream.wseq.zip Stream'.WSeq.zip
def findIndexes (p : α → Prop) [DecidablePred p] (s : WSeq α) : WSeq ℕ :=
(zip s (Stream'.nats : WSeq ℕ)).filterMap fun ⟨a, n⟩ => if p a then some n else none
#align stream.wseq.find_indexes Stream'.WSeq.findIndexes
def findIndex (p : α → Prop) [DecidablePred p] (s : WSeq α) : Computation ℕ :=
(fun o => Option.getD o 0) <$> head (findIndexes p s)
#align stream.wseq.find_index Stream'.WSeq.findIndex
def indexOf [DecidableEq α] (a : α) : WSeq α → Computation ℕ :=
findIndex (Eq a)
#align stream.wseq.index_of Stream'.WSeq.indexOf
def indexesOf [DecidableEq α] (a : α) : WSeq α → WSeq ℕ :=
findIndexes (Eq a)
#align stream.wseq.indexes_of Stream'.WSeq.indexesOf
def union (s1 s2 : WSeq α) : WSeq α :=
@Seq.corec (Option α) (WSeq α × WSeq α)
(fun ⟨s1, s2⟩ =>
match Seq.destruct s1, Seq.destruct s2 with
| none, none => none
| some (a1, s1'), none => some (a1, s1', nil)
| none, some (a2, s2') => some (a2, nil, s2')
| some (none, s1'), some (none, s2') => some (none, s1', s2')
| some (some a1, s1'), some (none, s2') => some (some a1, s1', s2')
| some (none, s1'), some (some a2, s2') => some (some a2, s1', s2')
| some (some a1, s1'), some (some a2, s2') => some (some a1, cons a2 s1', s2'))
(s1, s2)
#align stream.wseq.union Stream'.WSeq.union
def isEmpty (s : WSeq α) : Computation Bool :=
Computation.map Option.isNone <| head s
#align stream.wseq.is_empty Stream'.WSeq.isEmpty
def compute (s : WSeq α) : WSeq α :=
match Seq.destruct s with
| some (none, s') => s'
| _ => s
#align stream.wseq.compute Stream'.WSeq.compute
def take (s : WSeq α) (n : ℕ) : WSeq α :=
@Seq.corec (Option α) (ℕ × WSeq α)
(fun ⟨n, s⟩ =>
match n, Seq.destruct s with
| 0, _ => none
| _ + 1, none => none
| m + 1, some (none, s') => some (none, m + 1, s')
| m + 1, some (some a, s') => some (some a, m, s'))
(n, s)
#align stream.wseq.take Stream'.WSeq.take
def splitAt (s : WSeq α) (n : ℕ) : Computation (List α × WSeq α) :=
@Computation.corec (List α × WSeq α) (ℕ × List α × WSeq α)
(fun ⟨n, l, s⟩ =>
match n, Seq.destruct s with
| 0, _ => Sum.inl (l.reverse, s)
| _ + 1, none => Sum.inl (l.reverse, s)
| _ + 1, some (none, s') => Sum.inr (n, l, s')
| m + 1, some (some a, s') => Sum.inr (m, a::l, s'))
(n, [], s)
#align stream.wseq.split_at Stream'.WSeq.splitAt
def any (s : WSeq α) (p : α → Bool) : Computation Bool :=
Computation.corec
(fun s : WSeq α =>
match Seq.destruct s with
| none => Sum.inl false
| some (none, s') => Sum.inr s'
| some (some a, s') => if p a then Sum.inl true else Sum.inr s')
s
#align stream.wseq.any Stream'.WSeq.any
def all (s : WSeq α) (p : α → Bool) : Computation Bool :=
Computation.corec
(fun s : WSeq α =>
match Seq.destruct s with
| none => Sum.inl true
| some (none, s') => Sum.inr s'
| some (some a, s') => if p a then Sum.inr s' else Sum.inl false)
s
#align stream.wseq.all Stream'.WSeq.all
def scanl (f : α → β → α) (a : α) (s : WSeq β) : WSeq α :=
cons a <|
@Seq.corec (Option α) (α × WSeq β)
(fun ⟨a, s⟩ =>
match Seq.destruct s with
| none => none
| some (none, s') => some (none, a, s')
| some (some b, s') =>
let a' := f a b
some (some a', a', s'))
(a, s)
#align stream.wseq.scanl Stream'.WSeq.scanl
def inits (s : WSeq α) : WSeq (List α) :=
cons [] <|
@Seq.corec (Option (List α)) (Batteries.DList α × WSeq α)
(fun ⟨l, s⟩ =>
match Seq.destruct s with
| none => none
| some (none, s') => some (none, l, s')
| some (some a, s') =>
let l' := l.push a
some (some l'.toList, l', s'))
(Batteries.DList.empty, s)
#align stream.wseq.inits Stream'.WSeq.inits
def collect (s : WSeq α) (n : ℕ) : List α :=
(Seq.take n s).filterMap id
#align stream.wseq.collect Stream'.WSeq.collect
def append : WSeq α → WSeq α → WSeq α :=
Seq.append
#align stream.wseq.append Stream'.WSeq.append
def map (f : α → β) : WSeq α → WSeq β :=
Seq.map (Option.map f)
#align stream.wseq.map Stream'.WSeq.map
def join (S : WSeq (WSeq α)) : WSeq α :=
Seq.join
((fun o : Option (WSeq α) =>
match o with
| none => Seq1.ret none
| some s => (none, s)) <$>
S)
#align stream.wseq.join Stream'.WSeq.join
def bind (s : WSeq α) (f : α → WSeq β) : WSeq β :=
join (map f s)
#align stream.wseq.bind Stream'.WSeq.bind
@[simp]
def LiftRelO (R : α → β → Prop) (C : WSeq α → WSeq β → Prop) :
Option (α × WSeq α) → Option (β × WSeq β) → Prop
| none, none => True
| some (a, s), some (b, t) => R a b ∧ C s t
| _, _ => False
#align stream.wseq.lift_rel_o Stream'.WSeq.LiftRelO
theorem LiftRelO.imp {R S : α → β → Prop} {C D : WSeq α → WSeq β → Prop} (H1 : ∀ a b, R a b → S a b)
(H2 : ∀ s t, C s t → D s t) : ∀ {o p}, LiftRelO R C o p → LiftRelO S D o p
| none, none, _ => trivial
| some (_, _), some (_, _), h => And.imp (H1 _ _) (H2 _ _) h
| none, some _, h => False.elim h
| some (_, _), none, h => False.elim h
#align stream.wseq.lift_rel_o.imp Stream'.WSeq.LiftRelO.imp
theorem LiftRelO.imp_right (R : α → β → Prop) {C D : WSeq α → WSeq β → Prop}
(H : ∀ s t, C s t → D s t) {o p} : LiftRelO R C o p → LiftRelO R D o p :=
LiftRelO.imp (fun _ _ => id) H
#align stream.wseq.lift_rel_o.imp_right Stream'.WSeq.LiftRelO.imp_right
@[simp]
def BisimO (R : WSeq α → WSeq α → Prop) : Option (α × WSeq α) → Option (α × WSeq α) → Prop :=
LiftRelO (· = ·) R
#align stream.wseq.bisim_o Stream'.WSeq.BisimO
theorem BisimO.imp {R S : WSeq α → WSeq α → Prop} (H : ∀ s t, R s t → S s t) {o p} :
BisimO R o p → BisimO S o p :=
LiftRelO.imp_right _ H
#align stream.wseq.bisim_o.imp Stream'.WSeq.BisimO.imp
def LiftRel (R : α → β → Prop) (s : WSeq α) (t : WSeq β) : Prop :=
∃ C : WSeq α → WSeq β → Prop,
C s t ∧ ∀ {s t}, C s t → Computation.LiftRel (LiftRelO R C) (destruct s) (destruct t)
#align stream.wseq.lift_rel Stream'.WSeq.LiftRel
def Equiv : WSeq α → WSeq α → Prop :=
LiftRel (· = ·)
#align stream.wseq.equiv Stream'.WSeq.Equiv
theorem liftRel_destruct {R : α → β → Prop} {s : WSeq α} {t : WSeq β} :
LiftRel R s t → Computation.LiftRel (LiftRelO R (LiftRel R)) (destruct s) (destruct t)
| ⟨R, h1, h2⟩ => by
refine Computation.LiftRel.imp ?_ _ _ (h2 h1)
apply LiftRelO.imp_right
exact fun s' t' h' => ⟨R, h', @h2⟩
#align stream.wseq.lift_rel_destruct Stream'.WSeq.liftRel_destruct
theorem liftRel_destruct_iff {R : α → β → Prop} {s : WSeq α} {t : WSeq β} :
LiftRel R s t ↔ Computation.LiftRel (LiftRelO R (LiftRel R)) (destruct s) (destruct t) :=
⟨liftRel_destruct, fun h =>
⟨fun s t =>
LiftRel R s t ∨ Computation.LiftRel (LiftRelO R (LiftRel R)) (destruct s) (destruct t),
Or.inr h, fun {s t} h => by
have h : Computation.LiftRel (LiftRelO R (LiftRel R)) (destruct s) (destruct t) := by
cases' h with h h
· exact liftRel_destruct h
· assumption
apply Computation.LiftRel.imp _ _ _ h
intro a b
apply LiftRelO.imp_right
intro s t
apply Or.inl⟩⟩
#align stream.wseq.lift_rel_destruct_iff Stream'.WSeq.liftRel_destruct_iff
-- Porting note: To avoid ambiguous notation, `~` became `~ʷ`.
infixl:50 " ~ʷ " => Equiv
theorem destruct_congr {s t : WSeq α} :
s ~ʷ t → Computation.LiftRel (BisimO (· ~ʷ ·)) (destruct s) (destruct t) :=
liftRel_destruct
#align stream.wseq.destruct_congr Stream'.WSeq.destruct_congr
theorem destruct_congr_iff {s t : WSeq α} :
s ~ʷ t ↔ Computation.LiftRel (BisimO (· ~ʷ ·)) (destruct s) (destruct t) :=
liftRel_destruct_iff
#align stream.wseq.destruct_congr_iff Stream'.WSeq.destruct_congr_iff
theorem LiftRel.refl (R : α → α → Prop) (H : Reflexive R) : Reflexive (LiftRel R) := fun s => by
refine ⟨(· = ·), rfl, fun {s t} (h : s = t) => ?_⟩
rw [← h]
apply Computation.LiftRel.refl
intro a
cases' a with a
· simp
· cases a
simp only [LiftRelO, and_true]
apply H
#align stream.wseq.lift_rel.refl Stream'.WSeq.LiftRel.refl
theorem LiftRelO.swap (R : α → β → Prop) (C) :
swap (LiftRelO R C) = LiftRelO (swap R) (swap C) := by
funext x y
rcases x with ⟨⟩ | ⟨hx, jx⟩ <;> rcases y with ⟨⟩ | ⟨hy, jy⟩ <;> rfl
#align stream.wseq.lift_rel_o.swap Stream'.WSeq.LiftRelO.swap
theorem LiftRel.swap_lem {R : α → β → Prop} {s1 s2} (h : LiftRel R s1 s2) :
LiftRel (swap R) s2 s1 := by
refine ⟨swap (LiftRel R), h, fun {s t} (h : LiftRel R t s) => ?_⟩
rw [← LiftRelO.swap, Computation.LiftRel.swap]
apply liftRel_destruct h
#align stream.wseq.lift_rel.swap_lem Stream'.WSeq.LiftRel.swap_lem
theorem LiftRel.swap (R : α → β → Prop) : swap (LiftRel R) = LiftRel (swap R) :=
funext fun _ => funext fun _ => propext ⟨LiftRel.swap_lem, LiftRel.swap_lem⟩
#align stream.wseq.lift_rel.swap Stream'.WSeq.LiftRel.swap
theorem LiftRel.symm (R : α → α → Prop) (H : Symmetric R) : Symmetric (LiftRel R) :=
fun s1 s2 (h : Function.swap (LiftRel R) s2 s1) => by rwa [LiftRel.swap, H.swap_eq] at h
#align stream.wseq.lift_rel.symm Stream'.WSeq.LiftRel.symm
theorem LiftRel.trans (R : α → α → Prop) (H : Transitive R) : Transitive (LiftRel R) :=
fun s t u h1 h2 => by
refine ⟨fun s u => ∃ t, LiftRel R s t ∧ LiftRel R t u, ⟨t, h1, h2⟩, fun {s u} h => ?_⟩
rcases h with ⟨t, h1, h2⟩
have h1 := liftRel_destruct h1
have h2 := liftRel_destruct h2
refine
Computation.liftRel_def.2
⟨(Computation.terminates_of_liftRel h1).trans (Computation.terminates_of_liftRel h2),
fun {a c} ha hc => ?_⟩
rcases h1.left ha with ⟨b, hb, t1⟩
have t2 := Computation.rel_of_liftRel h2 hb hc
cases' a with a <;> cases' c with c
· trivial
· cases b
· cases t2
· cases t1
· cases a
cases' b with b
· cases t1
· cases b
cases t2
· cases' a with a s
cases' b with b
· cases t1
cases' b with b t
cases' c with c u
cases' t1 with ab st
cases' t2 with bc tu
exact ⟨H ab bc, t, st, tu⟩
#align stream.wseq.lift_rel.trans Stream'.WSeq.LiftRel.trans
theorem LiftRel.equiv (R : α → α → Prop) : Equivalence R → Equivalence (LiftRel R)
| ⟨refl, symm, trans⟩ => ⟨LiftRel.refl R refl, @(LiftRel.symm R @symm), @(LiftRel.trans R @trans)⟩
#align stream.wseq.lift_rel.equiv Stream'.WSeq.LiftRel.equiv
@[refl]
theorem Equiv.refl : ∀ s : WSeq α, s ~ʷ s :=
LiftRel.refl (· = ·) Eq.refl
#align stream.wseq.equiv.refl Stream'.WSeq.Equiv.refl
@[symm]
theorem Equiv.symm : ∀ {s t : WSeq α}, s ~ʷ t → t ~ʷ s :=
@(LiftRel.symm (· = ·) (@Eq.symm _))
#align stream.wseq.equiv.symm Stream'.WSeq.Equiv.symm
@[trans]
theorem Equiv.trans : ∀ {s t u : WSeq α}, s ~ʷ t → t ~ʷ u → s ~ʷ u :=
@(LiftRel.trans (· = ·) (@Eq.trans _))
#align stream.wseq.equiv.trans Stream'.WSeq.Equiv.trans
theorem Equiv.equivalence : Equivalence (@Equiv α) :=
⟨@Equiv.refl _, @Equiv.symm _, @Equiv.trans _⟩
#align stream.wseq.equiv.equivalence Stream'.WSeq.Equiv.equivalence
open Computation
@[simp]
theorem destruct_nil : destruct (nil : WSeq α) = Computation.pure none :=
Computation.destruct_eq_pure rfl
#align stream.wseq.destruct_nil Stream'.WSeq.destruct_nil
@[simp]
theorem destruct_cons (a : α) (s) : destruct (cons a s) = Computation.pure (some (a, s)) :=
Computation.destruct_eq_pure <| by simp [destruct, cons, Computation.rmap]
#align stream.wseq.destruct_cons Stream'.WSeq.destruct_cons
@[simp]
theorem destruct_think (s : WSeq α) : destruct (think s) = (destruct s).think :=
Computation.destruct_eq_think <| by simp [destruct, think, Computation.rmap]
#align stream.wseq.destruct_think Stream'.WSeq.destruct_think
@[simp]
theorem seq_destruct_nil : Seq.destruct (nil : WSeq α) = none :=
Seq.destruct_nil
#align stream.wseq.seq_destruct_nil Stream'.WSeq.seq_destruct_nil
@[simp]
theorem seq_destruct_cons (a : α) (s) : Seq.destruct (cons a s) = some (some a, s) :=
Seq.destruct_cons _ _
#align stream.wseq.seq_destruct_cons Stream'.WSeq.seq_destruct_cons
@[simp]
theorem seq_destruct_think (s : WSeq α) : Seq.destruct (think s) = some (none, s) :=
Seq.destruct_cons _ _
#align stream.wseq.seq_destruct_think Stream'.WSeq.seq_destruct_think
@[simp]
theorem head_nil : head (nil : WSeq α) = Computation.pure none := by simp [head]
#align stream.wseq.head_nil Stream'.WSeq.head_nil
@[simp]
theorem head_cons (a : α) (s) : head (cons a s) = Computation.pure (some a) := by simp [head]
#align stream.wseq.head_cons Stream'.WSeq.head_cons
@[simp]
theorem head_think (s : WSeq α) : head (think s) = (head s).think := by simp [head]
#align stream.wseq.head_think Stream'.WSeq.head_think
@[simp]
theorem flatten_pure (s : WSeq α) : flatten (Computation.pure s) = s := by
refine Seq.eq_of_bisim (fun s1 s2 => flatten (Computation.pure s2) = s1) ?_ rfl
intro s' s h
rw [← h]
simp only [Seq.BisimO, flatten, Seq.omap, pure_def, Seq.corec_eq, destruct_pure]
cases Seq.destruct s with
| none => simp
| some val =>
cases' val with o s'
simp
#align stream.wseq.flatten_ret Stream'.WSeq.flatten_pure
@[simp]
theorem flatten_think (c : Computation (WSeq α)) : flatten c.think = think (flatten c) :=
Seq.destruct_eq_cons <| by simp [flatten, think]
#align stream.wseq.flatten_think Stream'.WSeq.flatten_think
@[simp]
theorem destruct_flatten (c : Computation (WSeq α)) : destruct (flatten c) = c >>= destruct := by
refine
Computation.eq_of_bisim
(fun c1 c2 => c1 = c2 ∨ ∃ c, c1 = destruct (flatten c) ∧ c2 = Computation.bind c destruct) ?_
(Or.inr ⟨c, rfl, rfl⟩)
intro c1 c2 h
exact
match c1, c2, h with
| c, _, Or.inl rfl => by cases c.destruct <;> simp
| _, _, Or.inr ⟨c, rfl, rfl⟩ => by
induction' c using Computation.recOn with a c' <;> simp
· cases (destruct a).destruct <;> simp
· exact Or.inr ⟨c', rfl, rfl⟩
#align stream.wseq.destruct_flatten Stream'.WSeq.destruct_flatten
theorem head_terminates_iff (s : WSeq α) : Terminates (head s) ↔ Terminates (destruct s) :=
terminates_map_iff _ (destruct s)
#align stream.wseq.head_terminates_iff Stream'.WSeq.head_terminates_iff
@[simp]
theorem tail_nil : tail (nil : WSeq α) = nil := by simp [tail]
#align stream.wseq.tail_nil Stream'.WSeq.tail_nil
@[simp]
theorem tail_cons (a : α) (s) : tail (cons a s) = s := by simp [tail]
#align stream.wseq.tail_cons Stream'.WSeq.tail_cons
@[simp]
theorem tail_think (s : WSeq α) : tail (think s) = (tail s).think := by simp [tail]
#align stream.wseq.tail_think Stream'.WSeq.tail_think
@[simp]
theorem dropn_nil (n) : drop (nil : WSeq α) n = nil := by induction n <;> simp [*, drop]
#align stream.wseq.dropn_nil Stream'.WSeq.dropn_nil
@[simp]
theorem dropn_cons (a : α) (s) (n) : drop (cons a s) (n + 1) = drop s n := by
induction n with
| zero => simp [drop]
| succ n n_ih =>
-- porting note (#10745): was `simp [*, drop]`.
simp [drop, ← n_ih]
#align stream.wseq.dropn_cons Stream'.WSeq.dropn_cons
@[simp]
theorem dropn_think (s : WSeq α) (n) : drop (think s) n = (drop s n).think := by
induction n <;> simp [*, drop]
#align stream.wseq.dropn_think Stream'.WSeq.dropn_think
theorem dropn_add (s : WSeq α) (m) : ∀ n, drop s (m + n) = drop (drop s m) n
| 0 => rfl
| n + 1 => congr_arg tail (dropn_add s m n)
#align stream.wseq.dropn_add Stream'.WSeq.dropn_add
theorem dropn_tail (s : WSeq α) (n) : drop (tail s) n = drop s (n + 1) := by
rw [Nat.add_comm]
symm
apply dropn_add
#align stream.wseq.dropn_tail Stream'.WSeq.dropn_tail
theorem get?_add (s : WSeq α) (m n) : get? s (m + n) = get? (drop s m) n :=
congr_arg head (dropn_add _ _ _)
#align stream.wseq.nth_add Stream'.WSeq.get?_add
theorem get?_tail (s : WSeq α) (n) : get? (tail s) n = get? s (n + 1) :=
congr_arg head (dropn_tail _ _)
#align stream.wseq.nth_tail Stream'.WSeq.get?_tail
@[simp]
theorem join_nil : join nil = (nil : WSeq α) :=
Seq.join_nil
#align stream.wseq.join_nil Stream'.WSeq.join_nil
@[simp]
theorem join_think (S : WSeq (WSeq α)) : join (think S) = think (join S) := by
simp only [join, think]
dsimp only [(· <$> ·)]
simp [join, Seq1.ret]
#align stream.wseq.join_think Stream'.WSeq.join_think
@[simp]
theorem join_cons (s : WSeq α) (S) : join (cons s S) = think (append s (join S)) := by
simp only [join, think]
dsimp only [(· <$> ·)]
simp [join, cons, append]
#align stream.wseq.join_cons Stream'.WSeq.join_cons
@[simp]
theorem nil_append (s : WSeq α) : append nil s = s :=
Seq.nil_append _
#align stream.wseq.nil_append Stream'.WSeq.nil_append
@[simp]
theorem cons_append (a : α) (s t) : append (cons a s) t = cons a (append s t) :=
Seq.cons_append _ _ _
#align stream.wseq.cons_append Stream'.WSeq.cons_append
@[simp]
theorem think_append (s t : WSeq α) : append (think s) t = think (append s t) :=
Seq.cons_append _ _ _
#align stream.wseq.think_append Stream'.WSeq.think_append
@[simp]
theorem append_nil (s : WSeq α) : append s nil = s :=
Seq.append_nil _
#align stream.wseq.append_nil Stream'.WSeq.append_nil
@[simp]
theorem append_assoc (s t u : WSeq α) : append (append s t) u = append s (append t u) :=
Seq.append_assoc _ _ _
#align stream.wseq.append_assoc Stream'.WSeq.append_assoc
@[simp]
def tail.aux : Option (α × WSeq α) → Computation (Option (α × WSeq α))
| none => Computation.pure none
| some (_, s) => destruct s
#align stream.wseq.tail.aux Stream'.WSeq.tail.aux
theorem destruct_tail (s : WSeq α) : destruct (tail s) = destruct s >>= tail.aux := by
simp only [tail, destruct_flatten, tail.aux]; rw [← bind_pure_comp, LawfulMonad.bind_assoc]
apply congr_arg; ext1 (_ | ⟨a, s⟩) <;> apply (@pure_bind Computation _ _ _ _ _ _).trans _ <;> simp
#align stream.wseq.destruct_tail Stream'.WSeq.destruct_tail
@[simp]
def drop.aux : ℕ → Option (α × WSeq α) → Computation (Option (α × WSeq α))
| 0 => Computation.pure
| n + 1 => fun a => tail.aux a >>= drop.aux n
#align stream.wseq.drop.aux Stream'.WSeq.drop.aux
theorem drop.aux_none : ∀ n, @drop.aux α n none = Computation.pure none
| 0 => rfl
| n + 1 =>
show Computation.bind (Computation.pure none) (drop.aux n) = Computation.pure none by
rw [ret_bind, drop.aux_none n]
#align stream.wseq.drop.aux_none Stream'.WSeq.drop.aux_none
theorem destruct_dropn : ∀ (s : WSeq α) (n), destruct (drop s n) = destruct s >>= drop.aux n
| s, 0 => (bind_pure' _).symm
| s, n + 1 => by
rw [← dropn_tail, destruct_dropn _ n, destruct_tail, LawfulMonad.bind_assoc]
rfl
#align stream.wseq.destruct_dropn Stream'.WSeq.destruct_dropn
theorem head_terminates_of_head_tail_terminates (s : WSeq α) [T : Terminates (head (tail s))] :
Terminates (head s) :=
(head_terminates_iff _).2 <| by
rcases (head_terminates_iff _).1 T with ⟨⟨a, h⟩⟩
simp? [tail] at h says simp only [tail, destruct_flatten] at h
rcases exists_of_mem_bind h with ⟨s', h1, _⟩
unfold Functor.map at h1
exact
let ⟨t, h3, _⟩ := Computation.exists_of_mem_map h1
Computation.terminates_of_mem h3
#align stream.wseq.head_terminates_of_head_tail_terminates Stream'.WSeq.head_terminates_of_head_tail_terminates
theorem destruct_some_of_destruct_tail_some {s : WSeq α} {a} (h : some a ∈ destruct (tail s)) :
∃ a', some a' ∈ destruct s := by
unfold tail Functor.map at h; simp only [destruct_flatten] at h
rcases exists_of_mem_bind h with ⟨t, tm, td⟩; clear h
rcases Computation.exists_of_mem_map tm with ⟨t', ht', ht2⟩; clear tm
cases' t' with t' <;> rw [← ht2] at td <;> simp only [destruct_nil] at td
· have := mem_unique td (ret_mem _)
contradiction
· exact ⟨_, ht'⟩
#align stream.wseq.destruct_some_of_destruct_tail_some Stream'.WSeq.destruct_some_of_destruct_tail_some
theorem head_some_of_head_tail_some {s : WSeq α} {a} (h : some a ∈ head (tail s)) :
∃ a', some a' ∈ head s := by
unfold head at h
rcases Computation.exists_of_mem_map h with ⟨o, md, e⟩; clear h
cases' o with o <;> [injection e; injection e with h']; clear h'
cases' destruct_some_of_destruct_tail_some md with a am
exact ⟨_, Computation.mem_map (@Prod.fst α (WSeq α) <$> ·) am⟩
#align stream.wseq.head_some_of_head_tail_some Stream'.WSeq.head_some_of_head_tail_some
| Mathlib/Data/Seq/WSeq.lean | 862 | 868 | theorem head_some_of_get?_some {s : WSeq α} {a n} (h : some a ∈ get? s n) :
∃ a', some a' ∈ head s := by |
induction n generalizing a with
| zero => exact ⟨_, h⟩
| succ n IH =>
let ⟨a', h'⟩ := head_some_of_head_tail_some h
exact IH h'
|
import Mathlib.Init.Order.Defs
#align_import init.algebra.functions from "leanprover-community/lean"@"c2bcdbcbe741ed37c361a30d38e179182b989f76"
universe u
section
open Decidable
variable {α : Type u} [LinearOrder α]
theorem min_def (a b : α) : min a b = if a ≤ b then a else b := by
rw [LinearOrder.min_def a]
#align min_def min_def
theorem max_def (a b : α) : max a b = if a ≤ b then b else a := by
rw [LinearOrder.max_def a]
#align max_def max_def
theorem min_le_left (a b : α) : min a b ≤ a := by
-- Porting note: no `min_tac` tactic
if h : a ≤ b
then simp [min_def, if_pos h, le_refl]
else simp [min_def, if_neg h]; exact le_of_not_le h
#align min_le_left min_le_left
theorem min_le_right (a b : α) : min a b ≤ b := by
-- Porting note: no `min_tac` tactic
if h : a ≤ b
then simp [min_def, if_pos h]; exact h
else simp [min_def, if_neg h, le_refl]
#align min_le_right min_le_right
theorem le_min {a b c : α} (h₁ : c ≤ a) (h₂ : c ≤ b) : c ≤ min a b := by
-- Porting note: no `min_tac` tactic
if h : a ≤ b
then simp [min_def, if_pos h]; exact h₁
else simp [min_def, if_neg h]; exact h₂
#align le_min le_min
theorem le_max_left (a b : α) : a ≤ max a b := by
-- Porting note: no `min_tac` tactic
if h : a ≤ b
then simp [max_def, if_pos h]; exact h
else simp [max_def, if_neg h, le_refl]
#align le_max_left le_max_left
theorem le_max_right (a b : α) : b ≤ max a b := by
-- Porting note: no `min_tac` tactic
if h : a ≤ b
then simp [max_def, if_pos h, le_refl]
else simp [max_def, if_neg h]; exact le_of_not_le h
#align le_max_right le_max_right
theorem max_le {a b c : α} (h₁ : a ≤ c) (h₂ : b ≤ c) : max a b ≤ c := by
-- Porting note: no `min_tac` tactic
if h : a ≤ b
then simp [max_def, if_pos h]; exact h₂
else simp [max_def, if_neg h]; exact h₁
#align max_le max_le
theorem eq_min {a b c : α} (h₁ : c ≤ a) (h₂ : c ≤ b) (h₃ : ∀ {d}, d ≤ a → d ≤ b → d ≤ c) :
c = min a b :=
le_antisymm (le_min h₁ h₂) (h₃ (min_le_left a b) (min_le_right a b))
#align eq_min eq_min
theorem min_comm (a b : α) : min a b = min b a :=
eq_min (min_le_right a b) (min_le_left a b) fun h₁ h₂ => le_min h₂ h₁
#align min_comm min_comm
theorem min_assoc (a b c : α) : min (min a b) c = min a (min b c) := by
apply eq_min
· apply le_trans; apply min_le_left; apply min_le_left
· apply le_min; apply le_trans; apply min_le_left; apply min_le_right; apply min_le_right
· intro d h₁ h₂; apply le_min; apply le_min h₁; apply le_trans h₂; apply min_le_left
apply le_trans h₂; apply min_le_right
#align min_assoc min_assoc
theorem min_left_comm : ∀ a b c : α, min a (min b c) = min b (min a c) :=
left_comm (@min α _) (@min_comm α _) (@min_assoc α _)
#align min_left_comm min_left_comm
@[simp]
theorem min_self (a : α) : min a a = a := by simp [min_def]
#align min_self min_self
theorem min_eq_left {a b : α} (h : a ≤ b) : min a b = a := by
apply Eq.symm; apply eq_min (le_refl _) h; intros; assumption
#align min_eq_left min_eq_left
theorem min_eq_right {a b : α} (h : b ≤ a) : min a b = b :=
min_comm b a ▸ min_eq_left h
#align min_eq_right min_eq_right
theorem eq_max {a b c : α} (h₁ : a ≤ c) (h₂ : b ≤ c) (h₃ : ∀ {d}, a ≤ d → b ≤ d → c ≤ d) :
c = max a b :=
le_antisymm (h₃ (le_max_left a b) (le_max_right a b)) (max_le h₁ h₂)
#align eq_max eq_max
theorem max_comm (a b : α) : max a b = max b a :=
eq_max (le_max_right a b) (le_max_left a b) fun h₁ h₂ => max_le h₂ h₁
#align max_comm max_comm
| Mathlib/Init/Order/LinearOrder.lean | 117 | 122 | theorem max_assoc (a b c : α) : max (max a b) c = max a (max b c) := by |
apply eq_max
· apply le_trans; apply le_max_left a b; apply le_max_left
· apply max_le; apply le_trans; apply le_max_right a b; apply le_max_left; apply le_max_right
· intro d h₁ h₂; apply max_le; apply max_le h₁; apply le_trans (le_max_left _ _) h₂
apply le_trans (le_max_right _ _) h₂
|
import Mathlib.AlgebraicGeometry.Morphisms.Basic
import Mathlib.Topology.Spectral.Hom
import Mathlib.AlgebraicGeometry.Limits
#align_import algebraic_geometry.morphisms.quasi_compact from "leanprover-community/mathlib"@"5dc6092d09e5e489106865241986f7f2ad28d4c8"
noncomputable section
open CategoryTheory CategoryTheory.Limits Opposite TopologicalSpace
universe u
open scoped AlgebraicGeometry
namespace AlgebraicGeometry
variable {X Y : Scheme.{u}} (f : X ⟶ Y)
@[mk_iff]
class QuasiCompact (f : X ⟶ Y) : Prop where
isCompact_preimage : ∀ U : Set Y.carrier, IsOpen U → IsCompact U → IsCompact (f.1.base ⁻¹' U)
#align algebraic_geometry.quasi_compact AlgebraicGeometry.QuasiCompact
theorem quasiCompact_iff_spectral : QuasiCompact f ↔ IsSpectralMap f.1.base :=
⟨fun ⟨h⟩ => ⟨by continuity, h⟩, fun h => ⟨h.2⟩⟩
#align algebraic_geometry.quasi_compact_iff_spectral AlgebraicGeometry.quasiCompact_iff_spectral
def QuasiCompact.affineProperty : AffineTargetMorphismProperty := fun X _ _ _ =>
CompactSpace X.carrier
#align algebraic_geometry.quasi_compact.affine_property AlgebraicGeometry.QuasiCompact.affineProperty
instance (priority := 900) quasiCompactOfIsIso {X Y : Scheme} (f : X ⟶ Y) [IsIso f] :
QuasiCompact f := by
constructor
intro U _ hU'
convert hU'.image (inv f.1.base).continuous_toFun using 1
rw [Set.image_eq_preimage_of_inverse]
· delta Function.LeftInverse
exact IsIso.inv_hom_id_apply f.1.base
· exact IsIso.hom_inv_id_apply f.1.base
#align algebraic_geometry.quasi_compact_of_is_iso AlgebraicGeometry.quasiCompactOfIsIso
instance quasiCompactComp {X Y Z : Scheme} (f : X ⟶ Y) (g : Y ⟶ Z) [QuasiCompact f]
[QuasiCompact g] : QuasiCompact (f ≫ g) := by
constructor
intro U hU hU'
rw [Scheme.comp_val_base, TopCat.coe_comp, Set.preimage_comp]
apply QuasiCompact.isCompact_preimage
· exact Continuous.isOpen_preimage (by
-- Porting note: `continuity` failed
-- see https://github.com/leanprover-community/mathlib4/issues/5030
exact Scheme.Hom.continuous g) _ hU
apply QuasiCompact.isCompact_preimage <;> assumption
#align algebraic_geometry.quasi_compact_comp AlgebraicGeometry.quasiCompactComp
theorem isCompact_open_iff_eq_finset_affine_union {X : Scheme} (U : Set X.carrier) :
IsCompact U ∧ IsOpen U ↔
∃ s : Set X.affineOpens, s.Finite ∧ U = ⋃ (i : X.affineOpens) (_ : i ∈ s), i := by
apply Opens.IsBasis.isCompact_open_iff_eq_finite_iUnion
(fun (U : X.affineOpens) => (U : Opens X.carrier))
· rw [Subtype.range_coe]; exact isBasis_affine_open X
· exact fun i => i.2.isCompact
#align algebraic_geometry.is_compact_open_iff_eq_finset_affine_union AlgebraicGeometry.isCompact_open_iff_eq_finset_affine_union
theorem isCompact_open_iff_eq_basicOpen_union {X : Scheme} [IsAffine X] (U : Set X.carrier) :
IsCompact U ∧ IsOpen U ↔
∃ s : Set (X.presheaf.obj (op ⊤)),
s.Finite ∧ U = ⋃ (i : X.presheaf.obj (op ⊤)) (_ : i ∈ s), X.basicOpen i :=
(isBasis_basicOpen X).isCompact_open_iff_eq_finite_iUnion _
(fun _ => ((topIsAffineOpen _).basicOpenIsAffine _).isCompact) _
#align algebraic_geometry.is_compact_open_iff_eq_basic_open_union AlgebraicGeometry.isCompact_open_iff_eq_basicOpen_union
theorem quasiCompact_iff_forall_affine :
QuasiCompact f ↔
∀ U : Opens Y.carrier, IsAffineOpen U → IsCompact (f.1.base ⁻¹' (U : Set Y.carrier)) := by
rw [quasiCompact_iff]
refine ⟨fun H U hU => H U U.isOpen hU.isCompact, ?_⟩
intro H U hU hU'
obtain ⟨S, hS, rfl⟩ := (isCompact_open_iff_eq_finset_affine_union U).mp ⟨hU', hU⟩
simp only [Set.preimage_iUnion]
exact Set.Finite.isCompact_biUnion hS (fun i _ => H i i.prop)
#align algebraic_geometry.quasi_compact_iff_forall_affine AlgebraicGeometry.quasiCompact_iff_forall_affine
@[simp]
theorem QuasiCompact.affineProperty_toProperty {X Y : Scheme} (f : X ⟶ Y) :
(QuasiCompact.affineProperty : _).toProperty f ↔ IsAffine Y ∧ CompactSpace X.carrier := by
delta AffineTargetMorphismProperty.toProperty QuasiCompact.affineProperty; simp
#align algebraic_geometry.quasi_compact.affine_property_to_property AlgebraicGeometry.QuasiCompact.affineProperty_toProperty
theorem quasiCompact_iff_affineProperty :
QuasiCompact f ↔ targetAffineLocally QuasiCompact.affineProperty f := by
rw [quasiCompact_iff_forall_affine]
trans ∀ U : Y.affineOpens, IsCompact (f.1.base ⁻¹' (U : Set Y.carrier))
· exact ⟨fun h U => h U U.prop, fun h U hU => h ⟨U, hU⟩⟩
apply forall_congr'
exact fun _ => isCompact_iff_compactSpace
#align algebraic_geometry.quasi_compact_iff_affine_property AlgebraicGeometry.quasiCompact_iff_affineProperty
theorem quasiCompact_eq_affineProperty :
@QuasiCompact = targetAffineLocally QuasiCompact.affineProperty := by
ext
exact quasiCompact_iff_affineProperty _
#align algebraic_geometry.quasi_compact_eq_affine_property AlgebraicGeometry.quasiCompact_eq_affineProperty
theorem isCompact_basicOpen (X : Scheme) {U : Opens X.carrier} (hU : IsCompact (U : Set X.carrier))
(f : X.presheaf.obj (op U)) : IsCompact (X.basicOpen f : Set X.carrier) := by
classical
refine ((isCompact_open_iff_eq_finset_affine_union _).mpr ?_).1
obtain ⟨s, hs, e⟩ := (isCompact_open_iff_eq_finset_affine_union _).mp ⟨hU, U.isOpen⟩
let g : s → X.affineOpens := by
intro V
use V.1 ⊓ X.basicOpen f
have : V.1.1 ⟶ U := by
apply homOfLE; change _ ⊆ (U : Set X.carrier); rw [e]
convert Set.subset_iUnion₂ (s := fun (U : X.affineOpens) (_ : U ∈ s) => (U : Set X.carrier))
V V.prop using 1
erw [← X.toLocallyRingedSpace.toRingedSpace.basicOpen_res this.op]
exact IsAffineOpen.basicOpenIsAffine V.1.prop _
haveI : Finite s := hs.to_subtype
refine ⟨Set.range g, Set.finite_range g, ?_⟩
refine (Set.inter_eq_right.mpr
(SetLike.coe_subset_coe.2 <| RingedSpace.basicOpen_le _ _)).symm.trans ?_
rw [e, Set.iUnion₂_inter]
apply le_antisymm <;> apply Set.iUnion₂_subset
· intro i hi
-- Porting note: had to make explicit the first given parameter to `Set.subset_iUnion₂`
exact Set.Subset.trans (Set.Subset.rfl : _ ≤ g ⟨i, hi⟩)
(@Set.subset_iUnion₂ _ _ _
(fun (i : Scheme.affineOpens X) (_ : i ∈ Set.range g) => (i : Set X.toPresheafedSpace)) _
(Set.mem_range_self ⟨i, hi⟩))
· rintro ⟨i, hi⟩ ⟨⟨j, hj⟩, hj'⟩
rw [← hj']
refine Set.Subset.trans ?_ (Set.subset_iUnion₂ j hj)
exact Set.Subset.rfl
#align algebraic_geometry.is_compact_basic_open AlgebraicGeometry.isCompact_basicOpen
theorem QuasiCompact.affineProperty_isLocal : (QuasiCompact.affineProperty : _).IsLocal := by
constructor
· apply AffineTargetMorphismProperty.respectsIso_mk <;> rintro X Y Z e _ _ H
exacts [@Homeomorph.compactSpace _ _ _ _ H (TopCat.homeoOfIso (asIso e.inv.1.base)), H]
· introv H
dsimp [affineProperty] at H ⊢
change CompactSpace ((Opens.map f.val.base).obj (Y.basicOpen r))
rw [Scheme.preimage_basicOpen f r]
erw [← isCompact_iff_compactSpace]
rw [← isCompact_univ_iff] at H
apply isCompact_basicOpen
exact H
· rintro X Y H f S hS hS'
rw [← IsAffineOpen.basicOpen_union_eq_self_iff] at hS
· delta QuasiCompact.affineProperty
rw [← isCompact_univ_iff]
change IsCompact ((Opens.map f.val.base).obj ⊤).1
rw [← hS]
dsimp [Opens.map]
simp only [Opens.iSup_mk, Opens.carrier_eq_coe, Opens.coe_mk, Set.preimage_iUnion]
exact isCompact_iUnion fun i => isCompact_iff_compactSpace.mpr (hS' i)
· exact topIsAffineOpen _
#align algebraic_geometry.quasi_compact.affine_property_is_local AlgebraicGeometry.QuasiCompact.affineProperty_isLocal
theorem QuasiCompact.affine_openCover_tfae {X Y : Scheme.{u}} (f : X ⟶ Y) :
List.TFAE
[QuasiCompact f,
∃ (𝒰 : Scheme.OpenCover.{u} Y) (_ : ∀ i, IsAffine (𝒰.obj i)),
∀ i : 𝒰.J, CompactSpace (pullback f (𝒰.map i)).carrier,
∀ (𝒰 : Scheme.OpenCover.{u} Y) [∀ i, IsAffine (𝒰.obj i)] (i : 𝒰.J),
CompactSpace (pullback f (𝒰.map i)).carrier,
∀ {U : Scheme} (g : U ⟶ Y) [IsAffine U] [IsOpenImmersion g],
CompactSpace (pullback f g).carrier,
∃ (ι : Type u) (U : ι → Opens Y.carrier) (_ : iSup U = ⊤) (_ : ∀ i, IsAffineOpen (U i)),
∀ i, CompactSpace (f.1.base ⁻¹' (U i).1)] :=
quasiCompact_eq_affineProperty.symm ▸ QuasiCompact.affineProperty_isLocal.affine_openCover_TFAE f
#align algebraic_geometry.quasi_compact.affine_open_cover_tfae AlgebraicGeometry.QuasiCompact.affine_openCover_tfae
theorem QuasiCompact.is_local_at_target : PropertyIsLocalAtTarget @QuasiCompact :=
quasiCompact_eq_affineProperty.symm ▸
QuasiCompact.affineProperty_isLocal.targetAffineLocallyIsLocal
#align algebraic_geometry.quasi_compact.is_local_at_target AlgebraicGeometry.QuasiCompact.is_local_at_target
theorem QuasiCompact.openCover_tfae {X Y : Scheme.{u}} (f : X ⟶ Y) :
List.TFAE
[QuasiCompact f,
∃ 𝒰 : Scheme.OpenCover.{u} Y,
∀ i : 𝒰.J, QuasiCompact (pullback.snd : (𝒰.pullbackCover f).obj i ⟶ 𝒰.obj i),
∀ (𝒰 : Scheme.OpenCover.{u} Y) (i : 𝒰.J),
QuasiCompact (pullback.snd : (𝒰.pullbackCover f).obj i ⟶ 𝒰.obj i),
∀ U : Opens Y.carrier, QuasiCompact (f ∣_ U),
∀ {U : Scheme} (g : U ⟶ Y) [IsOpenImmersion g],
QuasiCompact (pullback.snd : pullback f g ⟶ _),
∃ (ι : Type u) (U : ι → Opens Y.carrier) (_ : iSup U = ⊤), ∀ i, QuasiCompact (f ∣_ U i)] :=
quasiCompact_eq_affineProperty.symm ▸
QuasiCompact.affineProperty_isLocal.targetAffineLocallyIsLocal.openCover_TFAE f
#align algebraic_geometry.quasi_compact.open_cover_tfae AlgebraicGeometry.QuasiCompact.openCover_tfae
theorem quasiCompact_over_affine_iff {X Y : Scheme} (f : X ⟶ Y) [IsAffine Y] :
QuasiCompact f ↔ CompactSpace X.carrier :=
quasiCompact_eq_affineProperty.symm ▸ QuasiCompact.affineProperty_isLocal.affine_target_iff f
#align algebraic_geometry.quasi_compact_over_affine_iff AlgebraicGeometry.quasiCompact_over_affine_iff
theorem compactSpace_iff_quasiCompact (X : Scheme) :
CompactSpace X.carrier ↔ QuasiCompact (terminal.from X) :=
(quasiCompact_over_affine_iff _).symm
#align algebraic_geometry.compact_space_iff_quasi_compact AlgebraicGeometry.compactSpace_iff_quasiCompact
theorem QuasiCompact.affine_openCover_iff {X Y : Scheme.{u}} (𝒰 : Scheme.OpenCover.{u} Y)
[∀ i, IsAffine (𝒰.obj i)] (f : X ⟶ Y) :
QuasiCompact f ↔ ∀ i, CompactSpace (pullback f (𝒰.map i)).carrier :=
quasiCompact_eq_affineProperty.symm ▸ QuasiCompact.affineProperty_isLocal.affine_openCover_iff f 𝒰
#align algebraic_geometry.quasi_compact.affine_open_cover_iff AlgebraicGeometry.QuasiCompact.affine_openCover_iff
theorem QuasiCompact.openCover_iff {X Y : Scheme.{u}} (𝒰 : Scheme.OpenCover.{u} Y) (f : X ⟶ Y) :
QuasiCompact f ↔ ∀ i, QuasiCompact (pullback.snd : pullback f (𝒰.map i) ⟶ _) :=
quasiCompact_eq_affineProperty.symm ▸
QuasiCompact.affineProperty_isLocal.targetAffineLocallyIsLocal.openCover_iff f 𝒰
#align algebraic_geometry.quasi_compact.open_cover_iff AlgebraicGeometry.QuasiCompact.openCover_iff
theorem quasiCompact_respectsIso : MorphismProperty.RespectsIso @QuasiCompact :=
quasiCompact_eq_affineProperty.symm ▸
targetAffineLocally_respectsIso QuasiCompact.affineProperty_isLocal.1
#align algebraic_geometry.quasi_compact_respects_iso AlgebraicGeometry.quasiCompact_respectsIso
instance quasiCompact_isStableUnderComposition :
MorphismProperty.IsStableUnderComposition @QuasiCompact where
comp_mem _ _ _ _ := inferInstance
#align algebraic_geometry.quasi_compact_stable_under_composition AlgebraicGeometry.quasiCompact_isStableUnderComposition
| Mathlib/AlgebraicGeometry/Morphisms/QuasiCompact.lean | 251 | 258 | theorem QuasiCompact.affineProperty_stableUnderBaseChange :
QuasiCompact.affineProperty.StableUnderBaseChange := by |
intro X Y S _ _ f g h
rw [QuasiCompact.affineProperty] at h ⊢
let 𝒰 := Scheme.Pullback.openCoverOfRight Y.affineCover.finiteSubcover f g
have : Finite 𝒰.J := by dsimp [𝒰]; infer_instance
have : ∀ i, CompactSpace (𝒰.obj i).carrier := by intro i; dsimp [𝒰]; infer_instance
exact 𝒰.compactSpace
|
import Mathlib.Algebra.FreeMonoid.Basic
import Mathlib.Algebra.Group.Submonoid.Membership
import Mathlib.GroupTheory.Congruence.Basic
import Mathlib.GroupTheory.FreeGroup.IsFreeGroup
import Mathlib.Data.List.Chain
import Mathlib.SetTheory.Cardinal.Basic
import Mathlib.Data.Set.Pointwise.SMul
#align_import group_theory.free_product from "leanprover-community/mathlib"@"9114ddffa023340c9ec86965e00cdd6fe26fcdf6"
open Set
variable {ι : Type*} (M : ι → Type*) [∀ i, Monoid (M i)]
inductive Monoid.CoprodI.Rel : FreeMonoid (Σi, M i) → FreeMonoid (Σi, M i) → Prop
| of_one (i : ι) : Monoid.CoprodI.Rel (FreeMonoid.of ⟨i, 1⟩) 1
| of_mul {i : ι} (x y : M i) :
Monoid.CoprodI.Rel (FreeMonoid.of ⟨i, x⟩ * FreeMonoid.of ⟨i, y⟩) (FreeMonoid.of ⟨i, x * y⟩)
#align free_product.rel Monoid.CoprodI.Rel
def Monoid.CoprodI : Type _ := (conGen (Monoid.CoprodI.Rel M)).Quotient
#align free_product Monoid.CoprodI
-- Porting note: could not de derived
instance : Monoid (Monoid.CoprodI M) := by
delta Monoid.CoprodI; infer_instance
instance : Inhabited (Monoid.CoprodI M) :=
⟨1⟩
namespace Monoid.CoprodI
@[ext]
structure Word where
toList : List (Σi, M i)
ne_one : ∀ l ∈ toList, Sigma.snd l ≠ 1
chain_ne : toList.Chain' fun l l' => Sigma.fst l ≠ Sigma.fst l'
#align free_product.word Monoid.CoprodI.Word
variable {M}
def of {i : ι} : M i →* CoprodI M where
toFun x := Con.mk' _ (FreeMonoid.of <| Sigma.mk i x)
map_one' := (Con.eq _).mpr (ConGen.Rel.of _ _ (CoprodI.Rel.of_one i))
map_mul' x y := Eq.symm <| (Con.eq _).mpr (ConGen.Rel.of _ _ (CoprodI.Rel.of_mul x y))
#align free_product.of Monoid.CoprodI.of
theorem of_apply {i} (m : M i) : of m = Con.mk' _ (FreeMonoid.of <| Sigma.mk i m) :=
rfl
#align free_product.of_apply Monoid.CoprodI.of_apply
variable {N : Type*} [Monoid N]
-- Porting note: higher `ext` priority
@[ext 1100]
theorem ext_hom (f g : CoprodI M →* N) (h : ∀ i, f.comp (of : M i →* _) = g.comp of) : f = g :=
(MonoidHom.cancel_right Con.mk'_surjective).mp <|
FreeMonoid.hom_eq fun ⟨i, x⟩ => by
-- This used to be `rw`, but we need `erw` after leanprover/lean4#2644
erw [MonoidHom.comp_apply, MonoidHom.comp_apply, ← of_apply, ← MonoidHom.comp_apply, ←
MonoidHom.comp_apply, h]; rfl
#align free_product.ext_hom Monoid.CoprodI.ext_hom
@[simps symm_apply]
def lift : (∀ i, M i →* N) ≃ (CoprodI M →* N) where
toFun fi :=
Con.lift _ (FreeMonoid.lift fun p : Σi, M i => fi p.fst p.snd) <|
Con.conGen_le <| by
simp_rw [Con.ker_rel]
rintro _ _ (i | ⟨x, y⟩)
· change FreeMonoid.lift _ (FreeMonoid.of _) = FreeMonoid.lift _ 1
simp only [MonoidHom.map_one, FreeMonoid.lift_eval_of]
· change
FreeMonoid.lift _ (FreeMonoid.of _ * FreeMonoid.of _) =
FreeMonoid.lift _ (FreeMonoid.of _)
simp only [MonoidHom.map_mul, FreeMonoid.lift_eval_of]
invFun f i := f.comp of
left_inv := by
intro fi
ext i x
-- This used to be `rw`, but we need `erw` after leanprover/lean4#2644
erw [MonoidHom.comp_apply, of_apply, Con.lift_mk', FreeMonoid.lift_eval_of]
right_inv := by
intro f
ext i x
rfl
#align free_product.lift Monoid.CoprodI.lift
@[simp]
theorem lift_comp_of {N} [Monoid N] (fi : ∀ i, M i →* N) i : (lift fi).comp of = fi i :=
congr_fun (lift.symm_apply_apply fi) i
@[simp]
theorem lift_of {N} [Monoid N] (fi : ∀ i, M i →* N) {i} (m : M i) : lift fi (of m) = fi i m :=
DFunLike.congr_fun (lift_comp_of ..) m
#align free_product.lift_of Monoid.CoprodI.lift_of
@[simp]
theorem lift_comp_of' {N} [Monoid N] (f : CoprodI M →* N) :
lift (fun i ↦ f.comp (of (i := i))) = f :=
lift.apply_symm_apply f
@[simp]
theorem lift_of' : lift (fun i ↦ (of : M i →* CoprodI M)) = .id (CoprodI M) :=
lift_comp_of' (.id _)
theorem of_leftInverse [DecidableEq ι] (i : ι) :
Function.LeftInverse (lift <| Pi.mulSingle i (MonoidHom.id (M i))) of := fun x => by
simp only [lift_of, Pi.mulSingle_eq_same, MonoidHom.id_apply]
#align free_product.of_left_inverse Monoid.CoprodI.of_leftInverse
theorem of_injective (i : ι) : Function.Injective (of : M i →* _) := by
classical exact (of_leftInverse i).injective
#align free_product.of_injective Monoid.CoprodI.of_injective
theorem mrange_eq_iSup {N} [Monoid N] (f : ∀ i, M i →* N) :
MonoidHom.mrange (lift f) = ⨆ i, MonoidHom.mrange (f i) := by
rw [lift, Equiv.coe_fn_mk, Con.lift_range, FreeMonoid.mrange_lift,
range_sigma_eq_iUnion_range, Submonoid.closure_iUnion]
simp only [MonoidHom.mclosure_range]
#align free_product.mrange_eq_supr Monoid.CoprodI.mrange_eq_iSup
theorem lift_mrange_le {N} [Monoid N] (f : ∀ i, M i →* N) {s : Submonoid N} :
MonoidHom.mrange (lift f) ≤ s ↔ ∀ i, MonoidHom.mrange (f i) ≤ s := by
simp [mrange_eq_iSup]
#align free_product.lift_mrange_le Monoid.CoprodI.lift_mrange_le
@[simp]
theorem iSup_mrange_of : ⨆ i, MonoidHom.mrange (of : M i →* CoprodI M) = ⊤ := by
simp [← mrange_eq_iSup]
@[simp]
theorem mclosure_iUnion_range_of :
Submonoid.closure (⋃ i, Set.range (of : M i →* CoprodI M)) = ⊤ := by
simp [Submonoid.closure_iUnion]
@[elab_as_elim]
theorem induction_left {C : CoprodI M → Prop} (m : CoprodI M) (one : C 1)
(mul : ∀ {i} (m : M i) x, C x → C (of m * x)) : C m := by
induction m using Submonoid.induction_of_closure_eq_top_left mclosure_iUnion_range_of with
| one => exact one
| mul x hx y ihy =>
obtain ⟨i, m, rfl⟩ : ∃ (i : ι) (m : M i), of m = x := by simpa using hx
exact mul m y ihy
@[elab_as_elim]
theorem induction_on {C : CoprodI M → Prop} (m : CoprodI M) (h_one : C 1)
(h_of : ∀ (i) (m : M i), C (of m)) (h_mul : ∀ x y, C x → C y → C (x * y)) : C m := by
induction m using CoprodI.induction_left with
| one => exact h_one
| mul m x hx => exact h_mul _ _ (h_of _ _) hx
#align free_product.induction_on Monoid.CoprodI.induction_on
namespace Word
@[simps]
def empty : Word M where
toList := []
ne_one := by simp
chain_ne := List.chain'_nil
#align free_product.word.empty Monoid.CoprodI.Word.empty
instance : Inhabited (Word M) :=
⟨empty⟩
def prod (w : Word M) : CoprodI M :=
List.prod (w.toList.map fun l => of l.snd)
#align free_product.word.prod Monoid.CoprodI.Word.prod
@[simp]
theorem prod_empty : prod (empty : Word M) = 1 :=
rfl
#align free_product.word.prod_empty Monoid.CoprodI.Word.prod_empty
def fstIdx (w : Word M) : Option ι :=
w.toList.head?.map Sigma.fst
#align free_product.word.fst_idx Monoid.CoprodI.Word.fstIdx
theorem fstIdx_ne_iff {w : Word M} {i} :
fstIdx w ≠ some i ↔ ∀ l ∈ w.toList.head?, i ≠ Sigma.fst l :=
not_iff_not.mp <| by simp [fstIdx]
#align free_product.word.fst_idx_ne_iff Monoid.CoprodI.Word.fstIdx_ne_iff
variable (M)
@[ext]
structure Pair (i : ι) where
head : M i
tail : Word M
fstIdx_ne : fstIdx tail ≠ some i
#align free_product.word.pair Monoid.CoprodI.Word.Pair
instance (i : ι) : Inhabited (Pair M i) :=
⟨⟨1, empty, by tauto⟩⟩
variable {M}
variable [∀ i, DecidableEq (M i)]
@[simps]
def cons {i} (m : M i) (w : Word M) (hmw : w.fstIdx ≠ some i) (h1 : m ≠ 1) : Word M :=
{ toList := ⟨i, m⟩ :: w.toList,
ne_one := by
simp only [List.mem_cons]
rintro l (rfl | hl)
· exact h1
· exact w.ne_one l hl
chain_ne := w.chain_ne.cons' (fstIdx_ne_iff.mp hmw) }
def rcons {i} (p : Pair M i) : Word M :=
if h : p.head = 1 then p.tail
else cons p.head p.tail p.fstIdx_ne h
#align free_product.word.rcons Monoid.CoprodI.Word.rcons
#noalign free_product.word.cons_eq_rcons
@[simp]
theorem prod_rcons {i} (p : Pair M i) : prod (rcons p) = of p.head * prod p.tail :=
if hm : p.head = 1 then by rw [rcons, dif_pos hm, hm, MonoidHom.map_one, one_mul]
else by rw [rcons, dif_neg hm, cons, prod, List.map_cons, List.prod_cons, prod]
#align free_product.word.prod_rcons Monoid.CoprodI.Word.prod_rcons
theorem rcons_inj {i} : Function.Injective (rcons : Pair M i → Word M) := by
rintro ⟨m, w, h⟩ ⟨m', w', h'⟩ he
by_cases hm : m = 1 <;> by_cases hm' : m' = 1
· simp only [rcons, dif_pos hm, dif_pos hm'] at he
aesop
· exfalso
simp only [rcons, dif_pos hm, dif_neg hm'] at he
rw [he] at h
exact h rfl
· exfalso
simp only [rcons, dif_pos hm', dif_neg hm] at he
rw [← he] at h'
exact h' rfl
· have : m = m' ∧ w.toList = w'.toList := by
simpa [cons, rcons, dif_neg hm, dif_neg hm', true_and_iff, eq_self_iff_true, Subtype.mk_eq_mk,
heq_iff_eq, ← Subtype.ext_iff_val] using he
rcases this with ⟨rfl, h⟩
congr
exact Word.ext _ _ h
#align free_product.word.rcons_inj Monoid.CoprodI.Word.rcons_inj
theorem mem_rcons_iff {i j : ι} (p : Pair M i) (m : M j) :
⟨_, m⟩ ∈ (rcons p).toList ↔ ⟨_, m⟩ ∈ p.tail.toList ∨
m ≠ 1 ∧ (∃ h : i = j, m = h ▸ p.head) := by
simp only [rcons, cons, ne_eq]
by_cases hij : i = j
· subst i
by_cases hm : m = p.head
· subst m
split_ifs <;> simp_all
· split_ifs <;> simp_all
· split_ifs <;> simp_all [Ne.symm hij]
@[simp]
theorem fstIdx_cons {i} (m : M i) (w : Word M) (hmw : w.fstIdx ≠ some i) (h1 : m ≠ 1) :
fstIdx (cons m w hmw h1) = some i := by simp [cons, fstIdx]
@[simp]
| Mathlib/GroupTheory/CoprodI.lean | 410 | 412 | theorem prod_cons (i) (m : M i) (w : Word M) (h1 : m ≠ 1) (h2 : w.fstIdx ≠ some i) :
prod (cons m w h2 h1) = of m * prod w := by |
simp [cons, prod, List.map_cons, List.prod_cons]
|
import Mathlib.Algebra.CharZero.Defs
import Mathlib.Algebra.Group.Hom.Defs
import Mathlib.Algebra.Order.Monoid.Canonical.Defs
import Mathlib.Algebra.Order.Monoid.OrderDual
import Mathlib.Algebra.Order.ZeroLEOne
import Mathlib.Data.Nat.Cast.Defs
import Mathlib.Order.WithBot
#align_import algebra.order.monoid.with_top from "leanprover-community/mathlib"@"0111834459f5d7400215223ea95ae38a1265a907"
universe u v
variable {α : Type u} {β : Type v}
open Function
namespace WithTop
section Add
variable [Add α] {a b c d : WithTop α} {x y : α}
instance add : Add (WithTop α) :=
⟨Option.map₂ (· + ·)⟩
#align with_top.has_add WithTop.add
@[simp, norm_cast] lemma coe_add (a b : α) : ↑(a + b) = (a + b : WithTop α) := rfl
#align with_top.coe_add WithTop.coe_add
#noalign with_top.coe_bit0
#noalign with_top.coe_bit1
@[simp]
theorem top_add (a : WithTop α) : ⊤ + a = ⊤ :=
rfl
#align with_top.top_add WithTop.top_add
@[simp]
theorem add_top (a : WithTop α) : a + ⊤ = ⊤ := by cases a <;> rfl
#align with_top.add_top WithTop.add_top
@[simp]
| Mathlib/Algebra/Order/Monoid/WithTop.lean | 132 | 136 | theorem add_eq_top : a + b = ⊤ ↔ a = ⊤ ∨ b = ⊤ := by |
match a, b with
| ⊤, _ => simp
| _, ⊤ => simp
| (a : α), (b : α) => simp only [← coe_add, coe_ne_top, or_false]
|
import Mathlib.Data.Matrix.Basic
#align_import data.matrix.block from "leanprover-community/mathlib"@"c060baa79af5ca092c54b8bf04f0f10592f59489"
variable {l m n o p q : Type*} {m' n' p' : o → Type*}
variable {R : Type*} {S : Type*} {α : Type*} {β : Type*}
open Matrix
namespace Matrix
theorem dotProduct_block [Fintype m] [Fintype n] [Mul α] [AddCommMonoid α] (v w : Sum m n → α) :
v ⬝ᵥ w = v ∘ Sum.inl ⬝ᵥ w ∘ Sum.inl + v ∘ Sum.inr ⬝ᵥ w ∘ Sum.inr :=
Fintype.sum_sum_type _
#align matrix.dot_product_block Matrix.dotProduct_block
section BlockMatrices
-- @[pp_nodot] -- Porting note: removed
def fromBlocks (A : Matrix n l α) (B : Matrix n m α) (C : Matrix o l α) (D : Matrix o m α) :
Matrix (Sum n o) (Sum l m) α :=
of <| Sum.elim (fun i => Sum.elim (A i) (B i)) fun i => Sum.elim (C i) (D i)
#align matrix.from_blocks Matrix.fromBlocks
@[simp]
theorem fromBlocks_apply₁₁ (A : Matrix n l α) (B : Matrix n m α) (C : Matrix o l α)
(D : Matrix o m α) (i : n) (j : l) : fromBlocks A B C D (Sum.inl i) (Sum.inl j) = A i j :=
rfl
#align matrix.from_blocks_apply₁₁ Matrix.fromBlocks_apply₁₁
@[simp]
theorem fromBlocks_apply₁₂ (A : Matrix n l α) (B : Matrix n m α) (C : Matrix o l α)
(D : Matrix o m α) (i : n) (j : m) : fromBlocks A B C D (Sum.inl i) (Sum.inr j) = B i j :=
rfl
#align matrix.from_blocks_apply₁₂ Matrix.fromBlocks_apply₁₂
@[simp]
theorem fromBlocks_apply₂₁ (A : Matrix n l α) (B : Matrix n m α) (C : Matrix o l α)
(D : Matrix o m α) (i : o) (j : l) : fromBlocks A B C D (Sum.inr i) (Sum.inl j) = C i j :=
rfl
#align matrix.from_blocks_apply₂₁ Matrix.fromBlocks_apply₂₁
@[simp]
theorem fromBlocks_apply₂₂ (A : Matrix n l α) (B : Matrix n m α) (C : Matrix o l α)
(D : Matrix o m α) (i : o) (j : m) : fromBlocks A B C D (Sum.inr i) (Sum.inr j) = D i j :=
rfl
#align matrix.from_blocks_apply₂₂ Matrix.fromBlocks_apply₂₂
def toBlocks₁₁ (M : Matrix (Sum n o) (Sum l m) α) : Matrix n l α :=
of fun i j => M (Sum.inl i) (Sum.inl j)
#align matrix.to_blocks₁₁ Matrix.toBlocks₁₁
def toBlocks₁₂ (M : Matrix (Sum n o) (Sum l m) α) : Matrix n m α :=
of fun i j => M (Sum.inl i) (Sum.inr j)
#align matrix.to_blocks₁₂ Matrix.toBlocks₁₂
def toBlocks₂₁ (M : Matrix (Sum n o) (Sum l m) α) : Matrix o l α :=
of fun i j => M (Sum.inr i) (Sum.inl j)
#align matrix.to_blocks₂₁ Matrix.toBlocks₂₁
def toBlocks₂₂ (M : Matrix (Sum n o) (Sum l m) α) : Matrix o m α :=
of fun i j => M (Sum.inr i) (Sum.inr j)
#align matrix.to_blocks₂₂ Matrix.toBlocks₂₂
theorem fromBlocks_toBlocks (M : Matrix (Sum n o) (Sum l m) α) :
fromBlocks M.toBlocks₁₁ M.toBlocks₁₂ M.toBlocks₂₁ M.toBlocks₂₂ = M := by
ext i j
rcases i with ⟨⟩ <;> rcases j with ⟨⟩ <;> rfl
#align matrix.from_blocks_to_blocks Matrix.fromBlocks_toBlocks
@[simp]
theorem toBlocks_fromBlocks₁₁ (A : Matrix n l α) (B : Matrix n m α) (C : Matrix o l α)
(D : Matrix o m α) : (fromBlocks A B C D).toBlocks₁₁ = A :=
rfl
#align matrix.to_blocks_from_blocks₁₁ Matrix.toBlocks_fromBlocks₁₁
@[simp]
theorem toBlocks_fromBlocks₁₂ (A : Matrix n l α) (B : Matrix n m α) (C : Matrix o l α)
(D : Matrix o m α) : (fromBlocks A B C D).toBlocks₁₂ = B :=
rfl
#align matrix.to_blocks_from_blocks₁₂ Matrix.toBlocks_fromBlocks₁₂
@[simp]
theorem toBlocks_fromBlocks₂₁ (A : Matrix n l α) (B : Matrix n m α) (C : Matrix o l α)
(D : Matrix o m α) : (fromBlocks A B C D).toBlocks₂₁ = C :=
rfl
#align matrix.to_blocks_from_blocks₂₁ Matrix.toBlocks_fromBlocks₂₁
@[simp]
theorem toBlocks_fromBlocks₂₂ (A : Matrix n l α) (B : Matrix n m α) (C : Matrix o l α)
(D : Matrix o m α) : (fromBlocks A B C D).toBlocks₂₂ = D :=
rfl
#align matrix.to_blocks_from_blocks₂₂ Matrix.toBlocks_fromBlocks₂₂
theorem ext_iff_blocks {A B : Matrix (Sum n o) (Sum l m) α} :
A = B ↔
A.toBlocks₁₁ = B.toBlocks₁₁ ∧
A.toBlocks₁₂ = B.toBlocks₁₂ ∧ A.toBlocks₂₁ = B.toBlocks₂₁ ∧ A.toBlocks₂₂ = B.toBlocks₂₂ :=
⟨fun h => h ▸ ⟨rfl, rfl, rfl, rfl⟩, fun ⟨h₁₁, h₁₂, h₂₁, h₂₂⟩ => by
rw [← fromBlocks_toBlocks A, ← fromBlocks_toBlocks B, h₁₁, h₁₂, h₂₁, h₂₂]⟩
#align matrix.ext_iff_blocks Matrix.ext_iff_blocks
@[simp]
theorem fromBlocks_inj {A : Matrix n l α} {B : Matrix n m α} {C : Matrix o l α} {D : Matrix o m α}
{A' : Matrix n l α} {B' : Matrix n m α} {C' : Matrix o l α} {D' : Matrix o m α} :
fromBlocks A B C D = fromBlocks A' B' C' D' ↔ A = A' ∧ B = B' ∧ C = C' ∧ D = D' :=
ext_iff_blocks
#align matrix.from_blocks_inj Matrix.fromBlocks_inj
theorem fromBlocks_map (A : Matrix n l α) (B : Matrix n m α) (C : Matrix o l α) (D : Matrix o m α)
(f : α → β) : (fromBlocks A B C D).map f =
fromBlocks (A.map f) (B.map f) (C.map f) (D.map f) := by
ext i j; rcases i with ⟨⟩ <;> rcases j with ⟨⟩ <;> simp [fromBlocks]
#align matrix.from_blocks_map Matrix.fromBlocks_map
theorem fromBlocks_transpose (A : Matrix n l α) (B : Matrix n m α) (C : Matrix o l α)
(D : Matrix o m α) : (fromBlocks A B C D)ᵀ = fromBlocks Aᵀ Cᵀ Bᵀ Dᵀ := by
ext i j
rcases i with ⟨⟩ <;> rcases j with ⟨⟩ <;> simp [fromBlocks]
#align matrix.from_blocks_transpose Matrix.fromBlocks_transpose
theorem fromBlocks_conjTranspose [Star α] (A : Matrix n l α) (B : Matrix n m α) (C : Matrix o l α)
(D : Matrix o m α) : (fromBlocks A B C D)ᴴ = fromBlocks Aᴴ Cᴴ Bᴴ Dᴴ := by
simp only [conjTranspose, fromBlocks_transpose, fromBlocks_map]
#align matrix.from_blocks_conj_transpose Matrix.fromBlocks_conjTranspose
@[simp]
theorem fromBlocks_submatrix_sum_swap_left (A : Matrix n l α) (B : Matrix n m α) (C : Matrix o l α)
(D : Matrix o m α) (f : p → Sum l m) :
(fromBlocks A B C D).submatrix Sum.swap f = (fromBlocks C D A B).submatrix id f := by
ext i j
cases i <;> dsimp <;> cases f j <;> rfl
#align matrix.from_blocks_submatrix_sum_swap_left Matrix.fromBlocks_submatrix_sum_swap_left
@[simp]
theorem fromBlocks_submatrix_sum_swap_right (A : Matrix n l α) (B : Matrix n m α) (C : Matrix o l α)
(D : Matrix o m α) (f : p → Sum n o) :
(fromBlocks A B C D).submatrix f Sum.swap = (fromBlocks B A D C).submatrix f id := by
ext i j
cases j <;> dsimp <;> cases f i <;> rfl
#align matrix.from_blocks_submatrix_sum_swap_right Matrix.fromBlocks_submatrix_sum_swap_right
theorem fromBlocks_submatrix_sum_swap_sum_swap {l m n o α : Type*} (A : Matrix n l α)
(B : Matrix n m α) (C : Matrix o l α) (D : Matrix o m α) :
(fromBlocks A B C D).submatrix Sum.swap Sum.swap = fromBlocks D C B A := by simp
#align matrix.from_blocks_submatrix_sum_swap_sum_swap Matrix.fromBlocks_submatrix_sum_swap_sum_swap
def IsTwoBlockDiagonal [Zero α] (A : Matrix (Sum n o) (Sum l m) α) : Prop :=
toBlocks₁₂ A = 0 ∧ toBlocks₂₁ A = 0
#align matrix.is_two_block_diagonal Matrix.IsTwoBlockDiagonal
def toBlock (M : Matrix m n α) (p : m → Prop) (q : n → Prop) : Matrix { a // p a } { a // q a } α :=
M.submatrix (↑) (↑)
#align matrix.to_block Matrix.toBlock
@[simp]
theorem toBlock_apply (M : Matrix m n α) (p : m → Prop) (q : n → Prop) (i : { a // p a })
(j : { a // q a }) : toBlock M p q i j = M ↑i ↑j :=
rfl
#align matrix.to_block_apply Matrix.toBlock_apply
def toSquareBlockProp (M : Matrix m m α) (p : m → Prop) : Matrix { a // p a } { a // p a } α :=
toBlock M _ _
#align matrix.to_square_block_prop Matrix.toSquareBlockProp
theorem toSquareBlockProp_def (M : Matrix m m α) (p : m → Prop) :
-- Porting note: added missing `of`
toSquareBlockProp M p = of (fun i j : { a // p a } => M ↑i ↑j) :=
rfl
#align matrix.to_square_block_prop_def Matrix.toSquareBlockProp_def
def toSquareBlock (M : Matrix m m α) (b : m → β) (k : β) :
Matrix { a // b a = k } { a // b a = k } α :=
toSquareBlockProp M _
#align matrix.to_square_block Matrix.toSquareBlock
theorem toSquareBlock_def (M : Matrix m m α) (b : m → β) (k : β) :
-- Porting note: added missing `of`
toSquareBlock M b k = of (fun i j : { a // b a = k } => M ↑i ↑j) :=
rfl
#align matrix.to_square_block_def Matrix.toSquareBlock_def
theorem fromBlocks_smul [SMul R α] (x : R) (A : Matrix n l α) (B : Matrix n m α) (C : Matrix o l α)
(D : Matrix o m α) : x • fromBlocks A B C D = fromBlocks (x • A) (x • B) (x • C) (x • D) := by
ext i j; rcases i with ⟨⟩ <;> rcases j with ⟨⟩ <;> simp [fromBlocks]
#align matrix.from_blocks_smul Matrix.fromBlocks_smul
theorem fromBlocks_neg [Neg R] (A : Matrix n l R) (B : Matrix n m R) (C : Matrix o l R)
(D : Matrix o m R) : -fromBlocks A B C D = fromBlocks (-A) (-B) (-C) (-D) := by
ext i j
cases i <;> cases j <;> simp [fromBlocks]
#align matrix.from_blocks_neg Matrix.fromBlocks_neg
@[simp]
theorem fromBlocks_zero [Zero α] : fromBlocks (0 : Matrix n l α) 0 0 (0 : Matrix o m α) = 0 := by
ext i j
rcases i with ⟨⟩ <;> rcases j with ⟨⟩ <;> rfl
#align matrix.from_blocks_zero Matrix.fromBlocks_zero
theorem fromBlocks_add [Add α] (A : Matrix n l α) (B : Matrix n m α) (C : Matrix o l α)
(D : Matrix o m α) (A' : Matrix n l α) (B' : Matrix n m α) (C' : Matrix o l α)
(D' : Matrix o m α) : fromBlocks A B C D + fromBlocks A' B' C' D' =
fromBlocks (A + A') (B + B') (C + C') (D + D') := by
ext i j; rcases i with ⟨⟩ <;> rcases j with ⟨⟩ <;> rfl
#align matrix.from_blocks_add Matrix.fromBlocks_add
theorem fromBlocks_multiply [Fintype l] [Fintype m] [NonUnitalNonAssocSemiring α] (A : Matrix n l α)
(B : Matrix n m α) (C : Matrix o l α) (D : Matrix o m α) (A' : Matrix l p α) (B' : Matrix l q α)
(C' : Matrix m p α) (D' : Matrix m q α) :
fromBlocks A B C D * fromBlocks A' B' C' D' =
fromBlocks (A * A' + B * C') (A * B' + B * D') (C * A' + D * C') (C * B' + D * D') := by
ext i j
rcases i with ⟨⟩ <;> rcases j with ⟨⟩ <;> simp only [fromBlocks, mul_apply, of_apply,
Sum.elim_inr, Fintype.sum_sum_type, Sum.elim_inl, add_apply]
#align matrix.from_blocks_multiply Matrix.fromBlocks_multiply
theorem fromBlocks_mulVec [Fintype l] [Fintype m] [NonUnitalNonAssocSemiring α] (A : Matrix n l α)
(B : Matrix n m α) (C : Matrix o l α) (D : Matrix o m α) (x : Sum l m → α) :
(fromBlocks A B C D) *ᵥ x =
Sum.elim (A *ᵥ (x ∘ Sum.inl) + B *ᵥ (x ∘ Sum.inr))
(C *ᵥ (x ∘ Sum.inl) + D *ᵥ (x ∘ Sum.inr)) := by
ext i
cases i <;> simp [mulVec, dotProduct]
#align matrix.from_blocks_mul_vec Matrix.fromBlocks_mulVec
theorem vecMul_fromBlocks [Fintype n] [Fintype o] [NonUnitalNonAssocSemiring α] (A : Matrix n l α)
(B : Matrix n m α) (C : Matrix o l α) (D : Matrix o m α) (x : Sum n o → α) :
x ᵥ* fromBlocks A B C D =
Sum.elim ((x ∘ Sum.inl) ᵥ* A + (x ∘ Sum.inr) ᵥ* C)
((x ∘ Sum.inl) ᵥ* B + (x ∘ Sum.inr) ᵥ* D) := by
ext i
cases i <;> simp [vecMul, dotProduct]
#align matrix.vec_mul_from_blocks Matrix.vecMul_fromBlocks
variable [DecidableEq l] [DecidableEq m]
section
variable [CommRing R]
| Mathlib/Data/Matrix/Block.lean | 938 | 944 | theorem toBlock_mul_eq_mul {m n k : Type*} [Fintype n] (p : m → Prop) (q : k → Prop)
(A : Matrix m n R) (B : Matrix n k R) :
(A * B).toBlock p q = A.toBlock p ⊤ * B.toBlock ⊤ q := by |
ext i k
simp only [toBlock_apply, mul_apply]
rw [Finset.sum_subtype]
simp [Pi.top_apply, Prop.top_eq_true]
|
import Mathlib.Analysis.SpecialFunctions.Trigonometric.Basic
import Mathlib.Topology.Order.ProjIcc
#align_import analysis.special_functions.trigonometric.inverse from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982"
noncomputable section
open scoped Classical
open Topology Filter
open Set Filter
open Real
namespace Real
variable {x y : ℝ}
-- @[pp_nodot] Porting note: not implemented
noncomputable def arcsin : ℝ → ℝ :=
Subtype.val ∘ IccExtend (neg_le_self zero_le_one) sinOrderIso.symm
#align real.arcsin Real.arcsin
theorem arcsin_mem_Icc (x : ℝ) : arcsin x ∈ Icc (-(π / 2)) (π / 2) :=
Subtype.coe_prop _
#align real.arcsin_mem_Icc Real.arcsin_mem_Icc
@[simp]
theorem range_arcsin : range arcsin = Icc (-(π / 2)) (π / 2) := by
rw [arcsin, range_comp Subtype.val]
simp [Icc]
#align real.range_arcsin Real.range_arcsin
theorem arcsin_le_pi_div_two (x : ℝ) : arcsin x ≤ π / 2 :=
(arcsin_mem_Icc x).2
#align real.arcsin_le_pi_div_two Real.arcsin_le_pi_div_two
theorem neg_pi_div_two_le_arcsin (x : ℝ) : -(π / 2) ≤ arcsin x :=
(arcsin_mem_Icc x).1
#align real.neg_pi_div_two_le_arcsin Real.neg_pi_div_two_le_arcsin
theorem arcsin_projIcc (x : ℝ) :
arcsin (projIcc (-1) 1 (neg_le_self zero_le_one) x) = arcsin x := by
rw [arcsin, Function.comp_apply, IccExtend_val, Function.comp_apply, IccExtend,
Function.comp_apply]
#align real.arcsin_proj_Icc Real.arcsin_projIcc
theorem sin_arcsin' {x : ℝ} (hx : x ∈ Icc (-1 : ℝ) 1) : sin (arcsin x) = x := by
simpa [arcsin, IccExtend_of_mem _ _ hx, -OrderIso.apply_symm_apply] using
Subtype.ext_iff.1 (sinOrderIso.apply_symm_apply ⟨x, hx⟩)
#align real.sin_arcsin' Real.sin_arcsin'
theorem sin_arcsin {x : ℝ} (hx₁ : -1 ≤ x) (hx₂ : x ≤ 1) : sin (arcsin x) = x :=
sin_arcsin' ⟨hx₁, hx₂⟩
#align real.sin_arcsin Real.sin_arcsin
theorem arcsin_sin' {x : ℝ} (hx : x ∈ Icc (-(π / 2)) (π / 2)) : arcsin (sin x) = x :=
injOn_sin (arcsin_mem_Icc _) hx <| by rw [sin_arcsin (neg_one_le_sin _) (sin_le_one _)]
#align real.arcsin_sin' Real.arcsin_sin'
theorem arcsin_sin {x : ℝ} (hx₁ : -(π / 2) ≤ x) (hx₂ : x ≤ π / 2) : arcsin (sin x) = x :=
arcsin_sin' ⟨hx₁, hx₂⟩
#align real.arcsin_sin Real.arcsin_sin
theorem strictMonoOn_arcsin : StrictMonoOn arcsin (Icc (-1) 1) :=
(Subtype.strictMono_coe _).comp_strictMonoOn <|
sinOrderIso.symm.strictMono.strictMonoOn_IccExtend _
#align real.strict_mono_on_arcsin Real.strictMonoOn_arcsin
theorem monotone_arcsin : Monotone arcsin :=
(Subtype.mono_coe _).comp <| sinOrderIso.symm.monotone.IccExtend _
#align real.monotone_arcsin Real.monotone_arcsin
theorem injOn_arcsin : InjOn arcsin (Icc (-1) 1) :=
strictMonoOn_arcsin.injOn
#align real.inj_on_arcsin Real.injOn_arcsin
theorem arcsin_inj {x y : ℝ} (hx₁ : -1 ≤ x) (hx₂ : x ≤ 1) (hy₁ : -1 ≤ y) (hy₂ : y ≤ 1) :
arcsin x = arcsin y ↔ x = y :=
injOn_arcsin.eq_iff ⟨hx₁, hx₂⟩ ⟨hy₁, hy₂⟩
#align real.arcsin_inj Real.arcsin_inj
@[continuity]
theorem continuous_arcsin : Continuous arcsin :=
continuous_subtype_val.comp sinOrderIso.symm.continuous.Icc_extend'
#align real.continuous_arcsin Real.continuous_arcsin
theorem continuousAt_arcsin {x : ℝ} : ContinuousAt arcsin x :=
continuous_arcsin.continuousAt
#align real.continuous_at_arcsin Real.continuousAt_arcsin
theorem arcsin_eq_of_sin_eq {x y : ℝ} (h₁ : sin x = y) (h₂ : x ∈ Icc (-(π / 2)) (π / 2)) :
arcsin y = x := by
subst y
exact injOn_sin (arcsin_mem_Icc _) h₂ (sin_arcsin' (sin_mem_Icc x))
#align real.arcsin_eq_of_sin_eq Real.arcsin_eq_of_sin_eq
@[simp]
theorem arcsin_zero : arcsin 0 = 0 :=
arcsin_eq_of_sin_eq sin_zero ⟨neg_nonpos.2 pi_div_two_pos.le, pi_div_two_pos.le⟩
#align real.arcsin_zero Real.arcsin_zero
@[simp]
theorem arcsin_one : arcsin 1 = π / 2 :=
arcsin_eq_of_sin_eq sin_pi_div_two <| right_mem_Icc.2 (neg_le_self pi_div_two_pos.le)
#align real.arcsin_one Real.arcsin_one
theorem arcsin_of_one_le {x : ℝ} (hx : 1 ≤ x) : arcsin x = π / 2 := by
rw [← arcsin_projIcc, projIcc_of_right_le _ hx, Subtype.coe_mk, arcsin_one]
#align real.arcsin_of_one_le Real.arcsin_of_one_le
theorem arcsin_neg_one : arcsin (-1) = -(π / 2) :=
arcsin_eq_of_sin_eq (by rw [sin_neg, sin_pi_div_two]) <|
left_mem_Icc.2 (neg_le_self pi_div_two_pos.le)
#align real.arcsin_neg_one Real.arcsin_neg_one
theorem arcsin_of_le_neg_one {x : ℝ} (hx : x ≤ -1) : arcsin x = -(π / 2) := by
rw [← arcsin_projIcc, projIcc_of_le_left _ hx, Subtype.coe_mk, arcsin_neg_one]
#align real.arcsin_of_le_neg_one Real.arcsin_of_le_neg_one
@[simp]
| Mathlib/Analysis/SpecialFunctions/Trigonometric/Inverse.lean | 138 | 145 | theorem arcsin_neg (x : ℝ) : arcsin (-x) = -arcsin x := by |
rcases le_total x (-1) with hx₁ | hx₁
· rw [arcsin_of_le_neg_one hx₁, neg_neg, arcsin_of_one_le (le_neg.2 hx₁)]
rcases le_total 1 x with hx₂ | hx₂
· rw [arcsin_of_one_le hx₂, arcsin_of_le_neg_one (neg_le_neg hx₂)]
refine arcsin_eq_of_sin_eq ?_ ?_
· rw [sin_neg, sin_arcsin hx₁ hx₂]
· exact ⟨neg_le_neg (arcsin_le_pi_div_two _), neg_le.2 (neg_pi_div_two_le_arcsin _)⟩
|
import Mathlib.Data.List.OfFn
import Mathlib.Data.List.Range
#align_import data.list.indexes from "leanprover-community/mathlib"@"8631e2d5ea77f6c13054d9151d82b83069680cb1"
assert_not_exists MonoidWithZero
universe u v
open Function
namespace List
variable {α : Type u} {β : Type v}
section MapIdx
-- Porting note: Add back old definition because it's easier for writing proofs.
protected def oldMapIdxCore (f : ℕ → α → β) : ℕ → List α → List β
| _, [] => []
| k, a :: as => f k a :: List.oldMapIdxCore f (k + 1) as
protected def oldMapIdx (f : ℕ → α → β) (as : List α) : List β :=
List.oldMapIdxCore f 0 as
@[simp]
theorem mapIdx_nil {α β} (f : ℕ → α → β) : mapIdx f [] = [] :=
rfl
#align list.map_with_index_nil List.mapIdx_nil
-- Porting note (#10756): new theorem.
protected theorem oldMapIdxCore_eq (l : List α) (f : ℕ → α → β) (n : ℕ) :
l.oldMapIdxCore f n = l.oldMapIdx fun i a ↦ f (i + n) a := by
induction' l with hd tl hl generalizing f n
· rfl
· rw [List.oldMapIdx]
simp only [List.oldMapIdxCore, hl, Nat.add_left_comm, Nat.add_comm, Nat.add_zero]
#noalign list.map_with_index_core_eq
-- Porting note: convert new definition to old definition.
-- A few new theorems are added to achieve this
-- 1. Prove that `oldMapIdxCore f (l ++ [e]) = oldMapIdxCore f l ++ [f l.length e]`
-- 2. Prove that `oldMapIdx f (l ++ [e]) = oldMapIdx f l ++ [f l.length e]`
-- 3. Prove list induction using `∀ l e, p [] → (p l → p (l ++ [e])) → p l`
-- Porting note (#10756): new theorem.
theorem list_reverse_induction (p : List α → Prop) (base : p [])
(ind : ∀ (l : List α) (e : α), p l → p (l ++ [e])) : (∀ (l : List α), p l) := by
let q := fun l ↦ p (reverse l)
have pq : ∀ l, p (reverse l) → q l := by simp only [q, reverse_reverse]; intro; exact id
have qp : ∀ l, q (reverse l) → p l := by simp only [q, reverse_reverse]; intro; exact id
intro l
apply qp
generalize (reverse l) = l
induction' l with head tail ih
· apply pq; simp only [reverse_nil, base]
· apply pq; simp only [reverse_cons]; apply ind; apply qp; rw [reverse_reverse]; exact ih
-- Porting note (#10756): new theorem.
protected theorem oldMapIdxCore_append : ∀ (f : ℕ → α → β) (n : ℕ) (l₁ l₂ : List α),
List.oldMapIdxCore f n (l₁ ++ l₂) =
List.oldMapIdxCore f n l₁ ++ List.oldMapIdxCore f (n + l₁.length) l₂ := by
intros f n l₁ l₂
generalize e : (l₁ ++ l₂).length = len
revert n l₁ l₂
induction' len with len ih <;> intros n l₁ l₂ h
· have l₁_nil : l₁ = [] := by
cases l₁
· rfl
· contradiction
have l₂_nil : l₂ = [] := by
cases l₂
· rfl
· rw [List.length_append] at h; contradiction
simp only [l₁_nil, l₂_nil]; rfl
· cases' l₁ with head tail
· rfl
· simp only [List.oldMapIdxCore, List.append_eq, length_cons, cons_append,cons.injEq, true_and]
suffices n + Nat.succ (length tail) = n + 1 + tail.length by
rw [this]
apply ih (n + 1) _ _ _
simp only [cons_append, length_cons, length_append, Nat.succ.injEq] at h
simp only [length_append, h]
rw [Nat.add_assoc]; simp only [Nat.add_comm]
-- Porting note (#10756): new theorem.
protected theorem oldMapIdx_append : ∀ (f : ℕ → α → β) (l : List α) (e : α),
List.oldMapIdx f (l ++ [e]) = List.oldMapIdx f l ++ [f l.length e] := by
intros f l e
unfold List.oldMapIdx
rw [List.oldMapIdxCore_append f 0 l [e]]
simp only [Nat.zero_add]; rfl
-- Porting note (#10756): new theorem.
theorem mapIdxGo_append : ∀ (f : ℕ → α → β) (l₁ l₂ : List α) (arr : Array β),
mapIdx.go f (l₁ ++ l₂) arr = mapIdx.go f l₂ (List.toArray (mapIdx.go f l₁ arr)) := by
intros f l₁ l₂ arr
generalize e : (l₁ ++ l₂).length = len
revert l₁ l₂ arr
induction' len with len ih <;> intros l₁ l₂ arr h
· have l₁_nil : l₁ = [] := by
cases l₁
· rfl
· contradiction
have l₂_nil : l₂ = [] := by
cases l₂
· rfl
· rw [List.length_append] at h; contradiction
rw [l₁_nil, l₂_nil]; simp only [mapIdx.go, Array.toList_eq, Array.toArray_data]
· cases' l₁ with head tail <;> simp only [mapIdx.go]
· simp only [nil_append, Array.toList_eq, Array.toArray_data]
· simp only [List.append_eq]
rw [ih]
· simp only [cons_append, length_cons, length_append, Nat.succ.injEq] at h
simp only [length_append, h]
-- Porting note (#10756): new theorem.
theorem mapIdxGo_length : ∀ (f : ℕ → α → β) (l : List α) (arr : Array β),
length (mapIdx.go f l arr) = length l + arr.size := by
intro f l
induction' l with head tail ih
· intro; simp only [mapIdx.go, Array.toList_eq, length_nil, Nat.zero_add]
· intro; simp only [mapIdx.go]; rw [ih]; simp only [Array.size_push, length_cons];
simp only [Nat.add_succ, add_zero, Nat.add_comm]
-- Porting note (#10756): new theorem.
theorem mapIdx_append_one : ∀ (f : ℕ → α → β) (l : List α) (e : α),
mapIdx f (l ++ [e]) = mapIdx f l ++ [f l.length e] := by
intros f l e
unfold mapIdx
rw [mapIdxGo_append f l [e]]
simp only [mapIdx.go, Array.size_toArray, mapIdxGo_length, length_nil, Nat.add_zero,
Array.toList_eq, Array.push_data, Array.data_toArray]
-- Porting note (#10756): new theorem.
protected theorem new_def_eq_old_def :
∀ (f : ℕ → α → β) (l : List α), l.mapIdx f = List.oldMapIdx f l := by
intro f
apply list_reverse_induction
· rfl
· intro l e h
rw [List.oldMapIdx_append, mapIdx_append_one, h]
@[local simp]
theorem map_enumFrom_eq_zipWith : ∀ (l : List α) (n : ℕ) (f : ℕ → α → β),
map (uncurry f) (enumFrom n l) = zipWith (fun i ↦ f (i + n)) (range (length l)) l := by
intro l
generalize e : l.length = len
revert l
induction' len with len ih <;> intros l e n f
· have : l = [] := by
cases l
· rfl
· contradiction
rw [this]; rfl
· cases' l with head tail
· contradiction
· simp only [map, uncurry_apply_pair, range_succ_eq_map, zipWith, Nat.zero_add,
zipWith_map_left]
rw [ih]
· suffices (fun i ↦ f (i + (n + 1))) = ((fun i ↦ f (i + n)) ∘ Nat.succ) by
rw [this]
rfl
funext n' a
simp only [comp, Nat.add_assoc, Nat.add_comm, Nat.add_succ]
simp only [length_cons, Nat.succ.injEq] at e; exact e
theorem mapIdx_eq_enum_map (l : List α) (f : ℕ → α → β) :
l.mapIdx f = l.enum.map (Function.uncurry f) := by
rw [List.new_def_eq_old_def]
induction' l with hd tl hl generalizing f
· rfl
· rw [List.oldMapIdx, List.oldMapIdxCore, List.oldMapIdxCore_eq, hl]
simp [map, enum_eq_zip_range, map_uncurry_zip_eq_zipWith]
#align list.map_with_index_eq_enum_map List.mapIdx_eq_enum_map
@[simp]
| Mathlib/Data/List/Indexes.lean | 192 | 195 | theorem mapIdx_cons (l : List α) (f : ℕ → α → β) (a : α) :
mapIdx f (a :: l) = f 0 a :: mapIdx (fun i ↦ f (i + 1)) l := by |
simp [mapIdx_eq_enum_map, enum_eq_zip_range, map_uncurry_zip_eq_zipWith,
range_succ_eq_map, zipWith_map_left]
|
import Mathlib.Algebra.Order.Ring.Defs
import Mathlib.Algebra.Group.Int
import Mathlib.Data.Nat.Dist
import Mathlib.Data.Ordmap.Ordnode
import Mathlib.Tactic.Abel
import Mathlib.Tactic.Linarith
#align_import data.ordmap.ordset from "leanprover-community/mathlib"@"47b51515e69f59bca5cf34ef456e6000fe205a69"
variable {α : Type*}
namespace Ordnode
theorem not_le_delta {s} (H : 1 ≤ s) : ¬s ≤ delta * 0 :=
not_le_of_gt H
#align ordnode.not_le_delta Ordnode.not_le_delta
theorem delta_lt_false {a b : ℕ} (h₁ : delta * a < b) (h₂ : delta * b < a) : False :=
not_le_of_lt (lt_trans ((mul_lt_mul_left (by decide)).2 h₁) h₂) <| by
simpa [mul_assoc] using Nat.mul_le_mul_right a (by decide : 1 ≤ delta * delta)
#align ordnode.delta_lt_false Ordnode.delta_lt_false
def realSize : Ordnode α → ℕ
| nil => 0
| node _ l _ r => realSize l + realSize r + 1
#align ordnode.real_size Ordnode.realSize
def Sized : Ordnode α → Prop
| nil => True
| node s l _ r => s = size l + size r + 1 ∧ Sized l ∧ Sized r
#align ordnode.sized Ordnode.Sized
theorem Sized.node' {l x r} (hl : @Sized α l) (hr : Sized r) : Sized (node' l x r) :=
⟨rfl, hl, hr⟩
#align ordnode.sized.node' Ordnode.Sized.node'
theorem Sized.eq_node' {s l x r} (h : @Sized α (node s l x r)) : node s l x r = .node' l x r := by
rw [h.1]
#align ordnode.sized.eq_node' Ordnode.Sized.eq_node'
theorem Sized.size_eq {s l x r} (H : Sized (@node α s l x r)) :
size (@node α s l x r) = size l + size r + 1 :=
H.1
#align ordnode.sized.size_eq Ordnode.Sized.size_eq
@[elab_as_elim]
theorem Sized.induction {t} (hl : @Sized α t) {C : Ordnode α → Prop} (H0 : C nil)
(H1 : ∀ l x r, C l → C r → C (.node' l x r)) : C t := by
induction t with
| nil => exact H0
| node _ _ _ _ t_ih_l t_ih_r =>
rw [hl.eq_node']
exact H1 _ _ _ (t_ih_l hl.2.1) (t_ih_r hl.2.2)
#align ordnode.sized.induction Ordnode.Sized.induction
theorem size_eq_realSize : ∀ {t : Ordnode α}, Sized t → size t = realSize t
| nil, _ => rfl
| node s l x r, ⟨h₁, h₂, h₃⟩ => by
rw [size, h₁, size_eq_realSize h₂, size_eq_realSize h₃]; rfl
#align ordnode.size_eq_real_size Ordnode.size_eq_realSize
@[simp]
| Mathlib/Data/Ordmap/Ordset.lean | 140 | 141 | theorem Sized.size_eq_zero {t : Ordnode α} (ht : Sized t) : size t = 0 ↔ t = nil := by |
cases t <;> [simp;simp [ht.1]]
|
import Mathlib.Analysis.SpecialFunctions.Trigonometric.Basic
import Mathlib.Analysis.Normed.Group.AddCircle
import Mathlib.Algebra.CharZero.Quotient
import Mathlib.Topology.Instances.Sign
#align_import analysis.special_functions.trigonometric.angle from "leanprover-community/mathlib"@"213b0cff7bc5ab6696ee07cceec80829ce42efec"
open Real
noncomputable section
namespace Real
-- Porting note: can't derive `NormedAddCommGroup, Inhabited`
def Angle : Type :=
AddCircle (2 * π)
#align real.angle Real.Angle
namespace Angle
-- Porting note (#10754): added due to missing instances due to no deriving
instance : NormedAddCommGroup Angle :=
inferInstanceAs (NormedAddCommGroup (AddCircle (2 * π)))
-- Porting note (#10754): added due to missing instances due to no deriving
instance : Inhabited Angle :=
inferInstanceAs (Inhabited (AddCircle (2 * π)))
-- Porting note (#10754): added due to missing instances due to no deriving
-- also, without this, a plain `QuotientAddGroup.mk`
-- causes coerced terms to be of type `ℝ ⧸ AddSubgroup.zmultiples (2 * π)`
@[coe]
protected def coe (r : ℝ) : Angle := QuotientAddGroup.mk r
instance : Coe ℝ Angle := ⟨Angle.coe⟩
instance : CircularOrder Real.Angle :=
QuotientAddGroup.circularOrder (hp' := ⟨by norm_num [pi_pos]⟩)
@[continuity]
theorem continuous_coe : Continuous ((↑) : ℝ → Angle) :=
continuous_quotient_mk'
#align real.angle.continuous_coe Real.Angle.continuous_coe
def coeHom : ℝ →+ Angle :=
QuotientAddGroup.mk' _
#align real.angle.coe_hom Real.Angle.coeHom
@[simp]
theorem coe_coeHom : (coeHom : ℝ → Angle) = ((↑) : ℝ → Angle) :=
rfl
#align real.angle.coe_coe_hom Real.Angle.coe_coeHom
@[elab_as_elim]
protected theorem induction_on {p : Angle → Prop} (θ : Angle) (h : ∀ x : ℝ, p x) : p θ :=
Quotient.inductionOn' θ h
#align real.angle.induction_on Real.Angle.induction_on
@[simp]
theorem coe_zero : ↑(0 : ℝ) = (0 : Angle) :=
rfl
#align real.angle.coe_zero Real.Angle.coe_zero
@[simp]
theorem coe_add (x y : ℝ) : ↑(x + y : ℝ) = (↑x + ↑y : Angle) :=
rfl
#align real.angle.coe_add Real.Angle.coe_add
@[simp]
theorem coe_neg (x : ℝ) : ↑(-x : ℝ) = -(↑x : Angle) :=
rfl
#align real.angle.coe_neg Real.Angle.coe_neg
@[simp]
theorem coe_sub (x y : ℝ) : ↑(x - y : ℝ) = (↑x - ↑y : Angle) :=
rfl
#align real.angle.coe_sub Real.Angle.coe_sub
theorem coe_nsmul (n : ℕ) (x : ℝ) : ↑(n • x : ℝ) = n • (↑x : Angle) :=
rfl
#align real.angle.coe_nsmul Real.Angle.coe_nsmul
theorem coe_zsmul (z : ℤ) (x : ℝ) : ↑(z • x : ℝ) = z • (↑x : Angle) :=
rfl
#align real.angle.coe_zsmul Real.Angle.coe_zsmul
@[simp, norm_cast]
theorem natCast_mul_eq_nsmul (x : ℝ) (n : ℕ) : ↑((n : ℝ) * x) = n • (↑x : Angle) := by
simpa only [nsmul_eq_mul] using coeHom.map_nsmul x n
#align real.angle.coe_nat_mul_eq_nsmul Real.Angle.natCast_mul_eq_nsmul
@[simp, norm_cast]
theorem intCast_mul_eq_zsmul (x : ℝ) (n : ℤ) : ↑((n : ℝ) * x : ℝ) = n • (↑x : Angle) := by
simpa only [zsmul_eq_mul] using coeHom.map_zsmul x n
#align real.angle.coe_int_mul_eq_zsmul Real.Angle.intCast_mul_eq_zsmul
@[deprecated (since := "2024-05-25")] alias coe_nat_mul_eq_nsmul := natCast_mul_eq_nsmul
@[deprecated (since := "2024-05-25")] alias coe_int_mul_eq_zsmul := intCast_mul_eq_zsmul
theorem angle_eq_iff_two_pi_dvd_sub {ψ θ : ℝ} : (θ : Angle) = ψ ↔ ∃ k : ℤ, θ - ψ = 2 * π * k := by
simp only [QuotientAddGroup.eq, AddSubgroup.zmultiples_eq_closure,
AddSubgroup.mem_closure_singleton, zsmul_eq_mul', (sub_eq_neg_add _ _).symm, eq_comm]
-- Porting note: added `rw`, `simp [Angle.coe, QuotientAddGroup.eq]` doesn't fire otherwise
rw [Angle.coe, Angle.coe, QuotientAddGroup.eq]
simp only [AddSubgroup.zmultiples_eq_closure,
AddSubgroup.mem_closure_singleton, zsmul_eq_mul', (sub_eq_neg_add _ _).symm, eq_comm]
#align real.angle.angle_eq_iff_two_pi_dvd_sub Real.Angle.angle_eq_iff_two_pi_dvd_sub
@[simp]
theorem coe_two_pi : ↑(2 * π : ℝ) = (0 : Angle) :=
angle_eq_iff_two_pi_dvd_sub.2 ⟨1, by rw [sub_zero, Int.cast_one, mul_one]⟩
#align real.angle.coe_two_pi Real.Angle.coe_two_pi
@[simp]
theorem neg_coe_pi : -(π : Angle) = π := by
rw [← coe_neg, angle_eq_iff_two_pi_dvd_sub]
use -1
simp [two_mul, sub_eq_add_neg]
#align real.angle.neg_coe_pi Real.Angle.neg_coe_pi
@[simp]
theorem two_nsmul_coe_div_two (θ : ℝ) : (2 : ℕ) • (↑(θ / 2) : Angle) = θ := by
rw [← coe_nsmul, two_nsmul, add_halves]
#align real.angle.two_nsmul_coe_div_two Real.Angle.two_nsmul_coe_div_two
@[simp]
theorem two_zsmul_coe_div_two (θ : ℝ) : (2 : ℤ) • (↑(θ / 2) : Angle) = θ := by
rw [← coe_zsmul, two_zsmul, add_halves]
#align real.angle.two_zsmul_coe_div_two Real.Angle.two_zsmul_coe_div_two
-- Porting note (#10618): @[simp] can prove it
theorem two_nsmul_neg_pi_div_two : (2 : ℕ) • (↑(-π / 2) : Angle) = π := by
rw [two_nsmul_coe_div_two, coe_neg, neg_coe_pi]
#align real.angle.two_nsmul_neg_pi_div_two Real.Angle.two_nsmul_neg_pi_div_two
-- Porting note (#10618): @[simp] can prove it
theorem two_zsmul_neg_pi_div_two : (2 : ℤ) • (↑(-π / 2) : Angle) = π := by
rw [two_zsmul, ← two_nsmul, two_nsmul_neg_pi_div_two]
#align real.angle.two_zsmul_neg_pi_div_two Real.Angle.two_zsmul_neg_pi_div_two
theorem sub_coe_pi_eq_add_coe_pi (θ : Angle) : θ - π = θ + π := by
rw [sub_eq_add_neg, neg_coe_pi]
#align real.angle.sub_coe_pi_eq_add_coe_pi Real.Angle.sub_coe_pi_eq_add_coe_pi
@[simp]
theorem two_nsmul_coe_pi : (2 : ℕ) • (π : Angle) = 0 := by simp [← natCast_mul_eq_nsmul]
#align real.angle.two_nsmul_coe_pi Real.Angle.two_nsmul_coe_pi
@[simp]
theorem two_zsmul_coe_pi : (2 : ℤ) • (π : Angle) = 0 := by simp [← intCast_mul_eq_zsmul]
#align real.angle.two_zsmul_coe_pi Real.Angle.two_zsmul_coe_pi
@[simp]
theorem coe_pi_add_coe_pi : (π : Real.Angle) + π = 0 := by rw [← two_nsmul, two_nsmul_coe_pi]
#align real.angle.coe_pi_add_coe_pi Real.Angle.coe_pi_add_coe_pi
theorem zsmul_eq_iff {ψ θ : Angle} {z : ℤ} (hz : z ≠ 0) :
z • ψ = z • θ ↔ ∃ k : Fin z.natAbs, ψ = θ + (k : ℕ) • (2 * π / z : ℝ) :=
QuotientAddGroup.zmultiples_zsmul_eq_zsmul_iff hz
#align real.angle.zsmul_eq_iff Real.Angle.zsmul_eq_iff
theorem nsmul_eq_iff {ψ θ : Angle} {n : ℕ} (hz : n ≠ 0) :
n • ψ = n • θ ↔ ∃ k : Fin n, ψ = θ + (k : ℕ) • (2 * π / n : ℝ) :=
QuotientAddGroup.zmultiples_nsmul_eq_nsmul_iff hz
#align real.angle.nsmul_eq_iff Real.Angle.nsmul_eq_iff
theorem two_zsmul_eq_iff {ψ θ : Angle} : (2 : ℤ) • ψ = (2 : ℤ) • θ ↔ ψ = θ ∨ ψ = θ + ↑π := by
-- Porting note: no `Int.natAbs_bit0` anymore
have : Int.natAbs 2 = 2 := rfl
rw [zsmul_eq_iff two_ne_zero, this, Fin.exists_fin_two, Fin.val_zero,
Fin.val_one, zero_smul, add_zero, one_smul, Int.cast_two,
mul_div_cancel_left₀ (_ : ℝ) two_ne_zero]
#align real.angle.two_zsmul_eq_iff Real.Angle.two_zsmul_eq_iff
theorem two_nsmul_eq_iff {ψ θ : Angle} : (2 : ℕ) • ψ = (2 : ℕ) • θ ↔ ψ = θ ∨ ψ = θ + ↑π := by
simp_rw [← natCast_zsmul, Nat.cast_ofNat, two_zsmul_eq_iff]
#align real.angle.two_nsmul_eq_iff Real.Angle.two_nsmul_eq_iff
theorem two_nsmul_eq_zero_iff {θ : Angle} : (2 : ℕ) • θ = 0 ↔ θ = 0 ∨ θ = π := by
convert two_nsmul_eq_iff <;> simp
#align real.angle.two_nsmul_eq_zero_iff Real.Angle.two_nsmul_eq_zero_iff
theorem two_nsmul_ne_zero_iff {θ : Angle} : (2 : ℕ) • θ ≠ 0 ↔ θ ≠ 0 ∧ θ ≠ π := by
rw [← not_or, ← two_nsmul_eq_zero_iff]
#align real.angle.two_nsmul_ne_zero_iff Real.Angle.two_nsmul_ne_zero_iff
theorem two_zsmul_eq_zero_iff {θ : Angle} : (2 : ℤ) • θ = 0 ↔ θ = 0 ∨ θ = π := by
simp_rw [two_zsmul, ← two_nsmul, two_nsmul_eq_zero_iff]
#align real.angle.two_zsmul_eq_zero_iff Real.Angle.two_zsmul_eq_zero_iff
theorem two_zsmul_ne_zero_iff {θ : Angle} : (2 : ℤ) • θ ≠ 0 ↔ θ ≠ 0 ∧ θ ≠ π := by
rw [← not_or, ← two_zsmul_eq_zero_iff]
#align real.angle.two_zsmul_ne_zero_iff Real.Angle.two_zsmul_ne_zero_iff
theorem eq_neg_self_iff {θ : Angle} : θ = -θ ↔ θ = 0 ∨ θ = π := by
rw [← add_eq_zero_iff_eq_neg, ← two_nsmul, two_nsmul_eq_zero_iff]
#align real.angle.eq_neg_self_iff Real.Angle.eq_neg_self_iff
theorem ne_neg_self_iff {θ : Angle} : θ ≠ -θ ↔ θ ≠ 0 ∧ θ ≠ π := by
rw [← not_or, ← eq_neg_self_iff.not]
#align real.angle.ne_neg_self_iff Real.Angle.ne_neg_self_iff
theorem neg_eq_self_iff {θ : Angle} : -θ = θ ↔ θ = 0 ∨ θ = π := by rw [eq_comm, eq_neg_self_iff]
#align real.angle.neg_eq_self_iff Real.Angle.neg_eq_self_iff
theorem neg_ne_self_iff {θ : Angle} : -θ ≠ θ ↔ θ ≠ 0 ∧ θ ≠ π := by
rw [← not_or, ← neg_eq_self_iff.not]
#align real.angle.neg_ne_self_iff Real.Angle.neg_ne_self_iff
theorem two_nsmul_eq_pi_iff {θ : Angle} : (2 : ℕ) • θ = π ↔ θ = (π / 2 : ℝ) ∨ θ = (-π / 2 : ℝ) := by
have h : (π : Angle) = ((2 : ℕ) • (π / 2 : ℝ) :) := by rw [two_nsmul, add_halves]
nth_rw 1 [h]
rw [coe_nsmul, two_nsmul_eq_iff]
-- Porting note: `congr` didn't simplify the goal of iff of `Or`s
convert Iff.rfl
rw [add_comm, ← coe_add, ← sub_eq_zero, ← coe_sub, neg_div, ← neg_sub, sub_neg_eq_add, add_assoc,
add_halves, ← two_mul, coe_neg, coe_two_pi, neg_zero]
#align real.angle.two_nsmul_eq_pi_iff Real.Angle.two_nsmul_eq_pi_iff
theorem two_zsmul_eq_pi_iff {θ : Angle} : (2 : ℤ) • θ = π ↔ θ = (π / 2 : ℝ) ∨ θ = (-π / 2 : ℝ) := by
rw [two_zsmul, ← two_nsmul, two_nsmul_eq_pi_iff]
#align real.angle.two_zsmul_eq_pi_iff Real.Angle.two_zsmul_eq_pi_iff
theorem cos_eq_iff_coe_eq_or_eq_neg {θ ψ : ℝ} :
cos θ = cos ψ ↔ (θ : Angle) = ψ ∨ (θ : Angle) = -ψ := by
constructor
· intro Hcos
rw [← sub_eq_zero, cos_sub_cos, mul_eq_zero, mul_eq_zero, neg_eq_zero,
eq_false (two_ne_zero' ℝ), false_or_iff, sin_eq_zero_iff, sin_eq_zero_iff] at Hcos
rcases Hcos with (⟨n, hn⟩ | ⟨n, hn⟩)
· right
rw [eq_div_iff_mul_eq (two_ne_zero' ℝ), ← sub_eq_iff_eq_add] at hn
rw [← hn, coe_sub, eq_neg_iff_add_eq_zero, sub_add_cancel, mul_assoc, intCast_mul_eq_zsmul,
mul_comm, coe_two_pi, zsmul_zero]
· left
rw [eq_div_iff_mul_eq (two_ne_zero' ℝ), eq_sub_iff_add_eq] at hn
rw [← hn, coe_add, mul_assoc, intCast_mul_eq_zsmul, mul_comm, coe_two_pi, zsmul_zero,
zero_add]
· rw [angle_eq_iff_two_pi_dvd_sub, ← coe_neg, angle_eq_iff_two_pi_dvd_sub]
rintro (⟨k, H⟩ | ⟨k, H⟩)
· rw [← sub_eq_zero, cos_sub_cos, H, mul_assoc 2 π k, mul_div_cancel_left₀ _ (two_ne_zero' ℝ),
mul_comm π _, sin_int_mul_pi, mul_zero]
rw [← sub_eq_zero, cos_sub_cos, ← sub_neg_eq_add, H, mul_assoc 2 π k,
mul_div_cancel_left₀ _ (two_ne_zero' ℝ), mul_comm π _, sin_int_mul_pi, mul_zero,
zero_mul]
#align real.angle.cos_eq_iff_coe_eq_or_eq_neg Real.Angle.cos_eq_iff_coe_eq_or_eq_neg
theorem sin_eq_iff_coe_eq_or_add_eq_pi {θ ψ : ℝ} :
sin θ = sin ψ ↔ (θ : Angle) = ψ ∨ (θ : Angle) + ψ = π := by
constructor
· intro Hsin
rw [← cos_pi_div_two_sub, ← cos_pi_div_two_sub] at Hsin
cases' cos_eq_iff_coe_eq_or_eq_neg.mp Hsin with h h
· left
rw [coe_sub, coe_sub] at h
exact sub_right_inj.1 h
right
rw [coe_sub, coe_sub, eq_neg_iff_add_eq_zero, add_sub, sub_add_eq_add_sub, ← coe_add,
add_halves, sub_sub, sub_eq_zero] at h
exact h.symm
· rw [angle_eq_iff_two_pi_dvd_sub, ← eq_sub_iff_add_eq, ← coe_sub, angle_eq_iff_two_pi_dvd_sub]
rintro (⟨k, H⟩ | ⟨k, H⟩)
· rw [← sub_eq_zero, sin_sub_sin, H, mul_assoc 2 π k, mul_div_cancel_left₀ _ (two_ne_zero' ℝ),
mul_comm π _, sin_int_mul_pi, mul_zero, zero_mul]
have H' : θ + ψ = 2 * k * π + π := by
rwa [← sub_add, sub_add_eq_add_sub, sub_eq_iff_eq_add, mul_assoc, mul_comm π _, ←
mul_assoc] at H
rw [← sub_eq_zero, sin_sub_sin, H', add_div, mul_assoc 2 _ π,
mul_div_cancel_left₀ _ (two_ne_zero' ℝ), cos_add_pi_div_two, sin_int_mul_pi, neg_zero,
mul_zero]
#align real.angle.sin_eq_iff_coe_eq_or_add_eq_pi Real.Angle.sin_eq_iff_coe_eq_or_add_eq_pi
theorem cos_sin_inj {θ ψ : ℝ} (Hcos : cos θ = cos ψ) (Hsin : sin θ = sin ψ) : (θ : Angle) = ψ := by
cases' cos_eq_iff_coe_eq_or_eq_neg.mp Hcos with hc hc; · exact hc
cases' sin_eq_iff_coe_eq_or_add_eq_pi.mp Hsin with hs hs; · exact hs
rw [eq_neg_iff_add_eq_zero, hs] at hc
obtain ⟨n, hn⟩ : ∃ n, n • _ = _ := QuotientAddGroup.leftRel_apply.mp (Quotient.exact' hc)
rw [← neg_one_mul, add_zero, ← sub_eq_zero, zsmul_eq_mul, ← mul_assoc, ← sub_mul, mul_eq_zero,
eq_false (ne_of_gt pi_pos), or_false_iff, sub_neg_eq_add, ← Int.cast_zero, ← Int.cast_one,
← Int.cast_ofNat, ← Int.cast_mul, ← Int.cast_add, Int.cast_inj] at hn
have : (n * 2 + 1) % (2 : ℤ) = 0 % (2 : ℤ) := congr_arg (· % (2 : ℤ)) hn
rw [add_comm, Int.add_mul_emod_self] at this
exact absurd this one_ne_zero
#align real.angle.cos_sin_inj Real.Angle.cos_sin_inj
def sin (θ : Angle) : ℝ :=
sin_periodic.lift θ
#align real.angle.sin Real.Angle.sin
@[simp]
theorem sin_coe (x : ℝ) : sin (x : Angle) = Real.sin x :=
rfl
#align real.angle.sin_coe Real.Angle.sin_coe
@[continuity]
theorem continuous_sin : Continuous sin :=
Real.continuous_sin.quotient_liftOn' _
#align real.angle.continuous_sin Real.Angle.continuous_sin
def cos (θ : Angle) : ℝ :=
cos_periodic.lift θ
#align real.angle.cos Real.Angle.cos
@[simp]
theorem cos_coe (x : ℝ) : cos (x : Angle) = Real.cos x :=
rfl
#align real.angle.cos_coe Real.Angle.cos_coe
@[continuity]
theorem continuous_cos : Continuous cos :=
Real.continuous_cos.quotient_liftOn' _
#align real.angle.continuous_cos Real.Angle.continuous_cos
theorem cos_eq_real_cos_iff_eq_or_eq_neg {θ : Angle} {ψ : ℝ} :
cos θ = Real.cos ψ ↔ θ = ψ ∨ θ = -ψ := by
induction θ using Real.Angle.induction_on
exact cos_eq_iff_coe_eq_or_eq_neg
#align real.angle.cos_eq_real_cos_iff_eq_or_eq_neg Real.Angle.cos_eq_real_cos_iff_eq_or_eq_neg
theorem cos_eq_iff_eq_or_eq_neg {θ ψ : Angle} : cos θ = cos ψ ↔ θ = ψ ∨ θ = -ψ := by
induction ψ using Real.Angle.induction_on
exact cos_eq_real_cos_iff_eq_or_eq_neg
#align real.angle.cos_eq_iff_eq_or_eq_neg Real.Angle.cos_eq_iff_eq_or_eq_neg
theorem sin_eq_real_sin_iff_eq_or_add_eq_pi {θ : Angle} {ψ : ℝ} :
sin θ = Real.sin ψ ↔ θ = ψ ∨ θ + ψ = π := by
induction θ using Real.Angle.induction_on
exact sin_eq_iff_coe_eq_or_add_eq_pi
#align real.angle.sin_eq_real_sin_iff_eq_or_add_eq_pi Real.Angle.sin_eq_real_sin_iff_eq_or_add_eq_pi
theorem sin_eq_iff_eq_or_add_eq_pi {θ ψ : Angle} : sin θ = sin ψ ↔ θ = ψ ∨ θ + ψ = π := by
induction ψ using Real.Angle.induction_on
exact sin_eq_real_sin_iff_eq_or_add_eq_pi
#align real.angle.sin_eq_iff_eq_or_add_eq_pi Real.Angle.sin_eq_iff_eq_or_add_eq_pi
@[simp]
theorem sin_zero : sin (0 : Angle) = 0 := by rw [← coe_zero, sin_coe, Real.sin_zero]
#align real.angle.sin_zero Real.Angle.sin_zero
-- Porting note (#10618): @[simp] can prove it
theorem sin_coe_pi : sin (π : Angle) = 0 := by rw [sin_coe, Real.sin_pi]
#align real.angle.sin_coe_pi Real.Angle.sin_coe_pi
theorem sin_eq_zero_iff {θ : Angle} : sin θ = 0 ↔ θ = 0 ∨ θ = π := by
nth_rw 1 [← sin_zero]
rw [sin_eq_iff_eq_or_add_eq_pi]
simp
#align real.angle.sin_eq_zero_iff Real.Angle.sin_eq_zero_iff
theorem sin_ne_zero_iff {θ : Angle} : sin θ ≠ 0 ↔ θ ≠ 0 ∧ θ ≠ π := by
rw [← not_or, ← sin_eq_zero_iff]
#align real.angle.sin_ne_zero_iff Real.Angle.sin_ne_zero_iff
@[simp]
theorem sin_neg (θ : Angle) : sin (-θ) = -sin θ := by
induction θ using Real.Angle.induction_on
exact Real.sin_neg _
#align real.angle.sin_neg Real.Angle.sin_neg
theorem sin_antiperiodic : Function.Antiperiodic sin (π : Angle) := by
intro θ
induction θ using Real.Angle.induction_on
exact Real.sin_antiperiodic _
#align real.angle.sin_antiperiodic Real.Angle.sin_antiperiodic
@[simp]
theorem sin_add_pi (θ : Angle) : sin (θ + π) = -sin θ :=
sin_antiperiodic θ
#align real.angle.sin_add_pi Real.Angle.sin_add_pi
@[simp]
theorem sin_sub_pi (θ : Angle) : sin (θ - π) = -sin θ :=
sin_antiperiodic.sub_eq θ
#align real.angle.sin_sub_pi Real.Angle.sin_sub_pi
@[simp]
theorem cos_zero : cos (0 : Angle) = 1 := by rw [← coe_zero, cos_coe, Real.cos_zero]
#align real.angle.cos_zero Real.Angle.cos_zero
-- Porting note (#10618): @[simp] can prove it
theorem cos_coe_pi : cos (π : Angle) = -1 := by rw [cos_coe, Real.cos_pi]
#align real.angle.cos_coe_pi Real.Angle.cos_coe_pi
@[simp]
theorem cos_neg (θ : Angle) : cos (-θ) = cos θ := by
induction θ using Real.Angle.induction_on
exact Real.cos_neg _
#align real.angle.cos_neg Real.Angle.cos_neg
theorem cos_antiperiodic : Function.Antiperiodic cos (π : Angle) := by
intro θ
induction θ using Real.Angle.induction_on
exact Real.cos_antiperiodic _
#align real.angle.cos_antiperiodic Real.Angle.cos_antiperiodic
@[simp]
theorem cos_add_pi (θ : Angle) : cos (θ + π) = -cos θ :=
cos_antiperiodic θ
#align real.angle.cos_add_pi Real.Angle.cos_add_pi
@[simp]
theorem cos_sub_pi (θ : Angle) : cos (θ - π) = -cos θ :=
cos_antiperiodic.sub_eq θ
#align real.angle.cos_sub_pi Real.Angle.cos_sub_pi
theorem cos_eq_zero_iff {θ : Angle} : cos θ = 0 ↔ θ = (π / 2 : ℝ) ∨ θ = (-π / 2 : ℝ) := by
rw [← cos_pi_div_two, ← cos_coe, cos_eq_iff_eq_or_eq_neg, ← coe_neg, ← neg_div]
#align real.angle.cos_eq_zero_iff Real.Angle.cos_eq_zero_iff
theorem sin_add (θ₁ θ₂ : Real.Angle) : sin (θ₁ + θ₂) = sin θ₁ * cos θ₂ + cos θ₁ * sin θ₂ := by
induction θ₁ using Real.Angle.induction_on
induction θ₂ using Real.Angle.induction_on
exact Real.sin_add _ _
#align real.angle.sin_add Real.Angle.sin_add
theorem cos_add (θ₁ θ₂ : Real.Angle) : cos (θ₁ + θ₂) = cos θ₁ * cos θ₂ - sin θ₁ * sin θ₂ := by
induction θ₂ using Real.Angle.induction_on
induction θ₁ using Real.Angle.induction_on
exact Real.cos_add _ _
#align real.angle.cos_add Real.Angle.cos_add
@[simp]
theorem cos_sq_add_sin_sq (θ : Real.Angle) : cos θ ^ 2 + sin θ ^ 2 = 1 := by
induction θ using Real.Angle.induction_on
exact Real.cos_sq_add_sin_sq _
#align real.angle.cos_sq_add_sin_sq Real.Angle.cos_sq_add_sin_sq
theorem sin_add_pi_div_two (θ : Angle) : sin (θ + ↑(π / 2)) = cos θ := by
induction θ using Real.Angle.induction_on
exact Real.sin_add_pi_div_two _
#align real.angle.sin_add_pi_div_two Real.Angle.sin_add_pi_div_two
theorem sin_sub_pi_div_two (θ : Angle) : sin (θ - ↑(π / 2)) = -cos θ := by
induction θ using Real.Angle.induction_on
exact Real.sin_sub_pi_div_two _
#align real.angle.sin_sub_pi_div_two Real.Angle.sin_sub_pi_div_two
theorem sin_pi_div_two_sub (θ : Angle) : sin (↑(π / 2) - θ) = cos θ := by
induction θ using Real.Angle.induction_on
exact Real.sin_pi_div_two_sub _
#align real.angle.sin_pi_div_two_sub Real.Angle.sin_pi_div_two_sub
theorem cos_add_pi_div_two (θ : Angle) : cos (θ + ↑(π / 2)) = -sin θ := by
induction θ using Real.Angle.induction_on
exact Real.cos_add_pi_div_two _
#align real.angle.cos_add_pi_div_two Real.Angle.cos_add_pi_div_two
theorem cos_sub_pi_div_two (θ : Angle) : cos (θ - ↑(π / 2)) = sin θ := by
induction θ using Real.Angle.induction_on
exact Real.cos_sub_pi_div_two _
#align real.angle.cos_sub_pi_div_two Real.Angle.cos_sub_pi_div_two
theorem cos_pi_div_two_sub (θ : Angle) : cos (↑(π / 2) - θ) = sin θ := by
induction θ using Real.Angle.induction_on
exact Real.cos_pi_div_two_sub _
#align real.angle.cos_pi_div_two_sub Real.Angle.cos_pi_div_two_sub
theorem abs_sin_eq_of_two_nsmul_eq {θ ψ : Angle} (h : (2 : ℕ) • θ = (2 : ℕ) • ψ) :
|sin θ| = |sin ψ| := by
rw [two_nsmul_eq_iff] at h
rcases h with (rfl | rfl)
· rfl
· rw [sin_add_pi, abs_neg]
#align real.angle.abs_sin_eq_of_two_nsmul_eq Real.Angle.abs_sin_eq_of_two_nsmul_eq
theorem abs_sin_eq_of_two_zsmul_eq {θ ψ : Angle} (h : (2 : ℤ) • θ = (2 : ℤ) • ψ) :
|sin θ| = |sin ψ| := by
simp_rw [two_zsmul, ← two_nsmul] at h
exact abs_sin_eq_of_two_nsmul_eq h
#align real.angle.abs_sin_eq_of_two_zsmul_eq Real.Angle.abs_sin_eq_of_two_zsmul_eq
theorem abs_cos_eq_of_two_nsmul_eq {θ ψ : Angle} (h : (2 : ℕ) • θ = (2 : ℕ) • ψ) :
|cos θ| = |cos ψ| := by
rw [two_nsmul_eq_iff] at h
rcases h with (rfl | rfl)
· rfl
· rw [cos_add_pi, abs_neg]
#align real.angle.abs_cos_eq_of_two_nsmul_eq Real.Angle.abs_cos_eq_of_two_nsmul_eq
theorem abs_cos_eq_of_two_zsmul_eq {θ ψ : Angle} (h : (2 : ℤ) • θ = (2 : ℤ) • ψ) :
|cos θ| = |cos ψ| := by
simp_rw [two_zsmul, ← two_nsmul] at h
exact abs_cos_eq_of_two_nsmul_eq h
#align real.angle.abs_cos_eq_of_two_zsmul_eq Real.Angle.abs_cos_eq_of_two_zsmul_eq
@[simp]
theorem coe_toIcoMod (θ ψ : ℝ) : ↑(toIcoMod two_pi_pos ψ θ) = (θ : Angle) := by
rw [angle_eq_iff_two_pi_dvd_sub]
refine ⟨-toIcoDiv two_pi_pos ψ θ, ?_⟩
rw [toIcoMod_sub_self, zsmul_eq_mul, mul_comm]
#align real.angle.coe_to_Ico_mod Real.Angle.coe_toIcoMod
@[simp]
theorem coe_toIocMod (θ ψ : ℝ) : ↑(toIocMod two_pi_pos ψ θ) = (θ : Angle) := by
rw [angle_eq_iff_two_pi_dvd_sub]
refine ⟨-toIocDiv two_pi_pos ψ θ, ?_⟩
rw [toIocMod_sub_self, zsmul_eq_mul, mul_comm]
#align real.angle.coe_to_Ioc_mod Real.Angle.coe_toIocMod
def toReal (θ : Angle) : ℝ :=
(toIocMod_periodic two_pi_pos (-π)).lift θ
#align real.angle.to_real Real.Angle.toReal
theorem toReal_coe (θ : ℝ) : (θ : Angle).toReal = toIocMod two_pi_pos (-π) θ :=
rfl
#align real.angle.to_real_coe Real.Angle.toReal_coe
theorem toReal_coe_eq_self_iff {θ : ℝ} : (θ : Angle).toReal = θ ↔ -π < θ ∧ θ ≤ π := by
rw [toReal_coe, toIocMod_eq_self two_pi_pos]
ring_nf
rfl
#align real.angle.to_real_coe_eq_self_iff Real.Angle.toReal_coe_eq_self_iff
| Mathlib/Analysis/SpecialFunctions/Trigonometric/Angle.lean | 536 | 537 | theorem toReal_coe_eq_self_iff_mem_Ioc {θ : ℝ} : (θ : Angle).toReal = θ ↔ θ ∈ Set.Ioc (-π) π := by |
rw [toReal_coe_eq_self_iff, ← Set.mem_Ioc]
|
import Mathlib.Analysis.InnerProductSpace.Orthogonal
import Mathlib.Analysis.Normed.Group.AddTorsor
#align_import geometry.euclidean.basic from "leanprover-community/mathlib"@"2de9c37fa71dde2f1c6feff19876dd6a7b1519f0"
open Set
open scoped RealInnerProductSpace
variable {V P : Type*} [NormedAddCommGroup V] [InnerProductSpace ℝ V] [MetricSpace P]
variable [NormedAddTorsor V P]
noncomputable section
namespace AffineSubspace
variable {c c₁ c₂ p₁ p₂ : P}
def perpBisector (p₁ p₂ : P) : AffineSubspace ℝ P :=
.comap ((AffineEquiv.vaddConst ℝ (midpoint ℝ p₁ p₂)).symm : P →ᵃ[ℝ] V) <|
(LinearMap.ker (innerₛₗ ℝ (p₂ -ᵥ p₁))).toAffineSubspace
theorem mem_perpBisector_iff_inner_eq_zero' :
c ∈ perpBisector p₁ p₂ ↔ ⟪p₂ -ᵥ p₁, c -ᵥ midpoint ℝ p₁ p₂⟫ = 0 :=
Iff.rfl
theorem mem_perpBisector_iff_inner_eq_zero :
c ∈ perpBisector p₁ p₂ ↔ ⟪c -ᵥ midpoint ℝ p₁ p₂, p₂ -ᵥ p₁⟫ = 0 :=
inner_eq_zero_symm
theorem mem_perpBisector_iff_inner_pointReflection_vsub_eq_zero :
c ∈ perpBisector p₁ p₂ ↔ ⟪Equiv.pointReflection c p₁ -ᵥ p₂, p₂ -ᵥ p₁⟫ = 0 := by
rw [mem_perpBisector_iff_inner_eq_zero, Equiv.pointReflection_apply,
vsub_midpoint, invOf_eq_inv, ← smul_add, real_inner_smul_left, vadd_vsub_assoc]
simp
theorem mem_perpBisector_pointReflection_iff_inner_eq_zero :
c ∈ perpBisector p₁ (Equiv.pointReflection p₂ p₁) ↔ ⟪c -ᵥ p₂, p₁ -ᵥ p₂⟫ = 0 := by
rw [mem_perpBisector_iff_inner_eq_zero, midpoint_pointReflection_right,
Equiv.pointReflection_apply, vadd_vsub_assoc, inner_add_right, add_self_eq_zero,
← neg_eq_zero, ← inner_neg_right, neg_vsub_eq_vsub_rev]
theorem midpoint_mem_perpBisector (p₁ p₂ : P) :
midpoint ℝ p₁ p₂ ∈ perpBisector p₁ p₂ := by
simp [mem_perpBisector_iff_inner_eq_zero]
theorem perpBisector_nonempty : (perpBisector p₁ p₂ : Set P).Nonempty :=
⟨_, midpoint_mem_perpBisector _ _⟩
@[simp]
theorem direction_perpBisector (p₁ p₂ : P) :
(perpBisector p₁ p₂).direction = (ℝ ∙ (p₂ -ᵥ p₁))ᗮ := by
erw [perpBisector, comap_symm, map_direction, Submodule.map_id,
Submodule.toAffineSubspace_direction]
ext x
exact Submodule.mem_orthogonal_singleton_iff_inner_right.symm
theorem mem_perpBisector_iff_inner_eq_inner :
c ∈ perpBisector p₁ p₂ ↔ ⟪c -ᵥ p₁, p₂ -ᵥ p₁⟫ = ⟪c -ᵥ p₂, p₁ -ᵥ p₂⟫ := by
rw [Iff.comm, mem_perpBisector_iff_inner_eq_zero, ← add_neg_eq_zero, ← inner_neg_right,
neg_vsub_eq_vsub_rev, ← inner_add_left, vsub_midpoint, invOf_eq_inv, ← smul_add,
real_inner_smul_left]; simp
theorem mem_perpBisector_iff_inner_eq :
c ∈ perpBisector p₁ p₂ ↔ ⟪c -ᵥ p₁, p₂ -ᵥ p₁⟫ = (dist p₁ p₂) ^ 2 / 2 := by
rw [mem_perpBisector_iff_inner_eq_zero, ← vsub_sub_vsub_cancel_right _ _ p₁, inner_sub_left,
sub_eq_zero, midpoint_vsub_left, invOf_eq_inv, real_inner_smul_left, real_inner_self_eq_norm_sq,
dist_eq_norm_vsub' V, div_eq_inv_mul]
theorem mem_perpBisector_iff_dist_eq : c ∈ perpBisector p₁ p₂ ↔ dist c p₁ = dist c p₂ := by
rw [dist_eq_norm_vsub V, dist_eq_norm_vsub V, ← real_inner_add_sub_eq_zero_iff,
vsub_sub_vsub_cancel_left, inner_add_left, add_eq_zero_iff_eq_neg, ← inner_neg_right,
neg_vsub_eq_vsub_rev, mem_perpBisector_iff_inner_eq_inner]
theorem mem_perpBisector_iff_dist_eq' : c ∈ perpBisector p₁ p₂ ↔ dist p₁ c = dist p₂ c := by
simp only [mem_perpBisector_iff_dist_eq, dist_comm]
| Mathlib/Geometry/Euclidean/PerpBisector.lean | 100 | 101 | theorem perpBisector_comm (p₁ p₂ : P) : perpBisector p₁ p₂ = perpBisector p₂ p₁ := by |
ext c; simp only [mem_perpBisector_iff_dist_eq, eq_comm]
|
import Mathlib.Algebra.Algebra.Operations
import Mathlib.Data.Fintype.Lattice
import Mathlib.RingTheory.Coprime.Lemmas
#align_import ring_theory.ideal.operations from "leanprover-community/mathlib"@"e7f0ddbf65bd7181a85edb74b64bdc35ba4bdc74"
assert_not_exists Basis -- See `RingTheory.Ideal.Basis`
assert_not_exists Submodule.hasQuotient -- See `RingTheory.Ideal.QuotientOperations`
universe u v w x
open Pointwise
namespace Submodule
variable {R : Type u} {M : Type v} {M' F G : Type*}
section CommSemiring
variable [CommSemiring R] [AddCommMonoid M] [Module R M] [AddCommMonoid M'] [Module R M']
open Pointwise
instance hasSMul' : SMul (Ideal R) (Submodule R M) :=
⟨Submodule.map₂ (LinearMap.lsmul R M)⟩
#align submodule.has_smul' Submodule.hasSMul'
protected theorem _root_.Ideal.smul_eq_mul (I J : Ideal R) : I • J = I * J :=
rfl
#align ideal.smul_eq_mul Ideal.smul_eq_mul
variable (R M) in
def _root_.Module.annihilator : Ideal R := LinearMap.ker (LinearMap.lsmul R M)
theorem _root_.Module.mem_annihilator {r} : r ∈ Module.annihilator R M ↔ ∀ m : M, r • m = 0 :=
⟨fun h ↦ (congr($h ·)), (LinearMap.ext ·)⟩
theorem _root_.LinearMap.annihilator_le_of_injective (f : M →ₗ[R] M') (hf : Function.Injective f) :
Module.annihilator R M' ≤ Module.annihilator R M := fun x h ↦ by
rw [Module.mem_annihilator] at h ⊢; exact fun m ↦ hf (by rw [map_smul, h, f.map_zero])
theorem _root_.LinearMap.annihilator_le_of_surjective (f : M →ₗ[R] M')
(hf : Function.Surjective f) : Module.annihilator R M ≤ Module.annihilator R M' := fun x h ↦ by
rw [Module.mem_annihilator] at h ⊢
intro m; obtain ⟨m, rfl⟩ := hf m
rw [← map_smul, h, f.map_zero]
theorem _root_.LinearEquiv.annihilator_eq (e : M ≃ₗ[R] M') :
Module.annihilator R M = Module.annihilator R M' :=
(e.annihilator_le_of_surjective e.surjective).antisymm (e.annihilator_le_of_injective e.injective)
abbrev annihilator (N : Submodule R M) : Ideal R :=
Module.annihilator R N
#align submodule.annihilator Submodule.annihilator
theorem annihilator_top : (⊤ : Submodule R M).annihilator = Module.annihilator R M :=
topEquiv.annihilator_eq
variable {I J : Ideal R} {N P : Submodule R M}
theorem mem_annihilator {r} : r ∈ N.annihilator ↔ ∀ n ∈ N, r • n = (0 : M) := by
simp_rw [annihilator, Module.mem_annihilator, Subtype.forall, Subtype.ext_iff]; rfl
#align submodule.mem_annihilator Submodule.mem_annihilator
theorem mem_annihilator' {r} : r ∈ N.annihilator ↔ N ≤ comap (r • (LinearMap.id : M →ₗ[R] M)) ⊥ :=
mem_annihilator.trans ⟨fun H n hn => (mem_bot R).2 <| H n hn, fun H _ hn => (mem_bot R).1 <| H hn⟩
#align submodule.mem_annihilator' Submodule.mem_annihilator'
theorem mem_annihilator_span (s : Set M) (r : R) :
r ∈ (Submodule.span R s).annihilator ↔ ∀ n : s, r • (n : M) = 0 := by
rw [Submodule.mem_annihilator]
constructor
· intro h n
exact h _ (Submodule.subset_span n.prop)
· intro h n hn
refine Submodule.span_induction hn ?_ ?_ ?_ ?_
· intro x hx
exact h ⟨x, hx⟩
· exact smul_zero _
· intro x y hx hy
rw [smul_add, hx, hy, zero_add]
· intro a x hx
rw [smul_comm, hx, smul_zero]
#align submodule.mem_annihilator_span Submodule.mem_annihilator_span
theorem mem_annihilator_span_singleton (g : M) (r : R) :
r ∈ (Submodule.span R ({g} : Set M)).annihilator ↔ r • g = 0 := by simp [mem_annihilator_span]
#align submodule.mem_annihilator_span_singleton Submodule.mem_annihilator_span_singleton
theorem annihilator_bot : (⊥ : Submodule R M).annihilator = ⊤ :=
(Ideal.eq_top_iff_one _).2 <| mem_annihilator'.2 bot_le
#align submodule.annihilator_bot Submodule.annihilator_bot
theorem annihilator_eq_top_iff : N.annihilator = ⊤ ↔ N = ⊥ :=
⟨fun H =>
eq_bot_iff.2 fun (n : M) hn =>
(mem_bot R).2 <| one_smul R n ▸ mem_annihilator.1 ((Ideal.eq_top_iff_one _).1 H) n hn,
fun H => H.symm ▸ annihilator_bot⟩
#align submodule.annihilator_eq_top_iff Submodule.annihilator_eq_top_iff
theorem annihilator_mono (h : N ≤ P) : P.annihilator ≤ N.annihilator := fun _ hrp =>
mem_annihilator.2 fun n hn => mem_annihilator.1 hrp n <| h hn
#align submodule.annihilator_mono Submodule.annihilator_mono
theorem annihilator_iSup (ι : Sort w) (f : ι → Submodule R M) :
annihilator (⨆ i, f i) = ⨅ i, annihilator (f i) :=
le_antisymm (le_iInf fun _ => annihilator_mono <| le_iSup _ _) fun _ H =>
mem_annihilator'.2 <|
iSup_le fun i =>
have := (mem_iInf _).1 H i
mem_annihilator'.1 this
#align submodule.annihilator_supr Submodule.annihilator_iSup
theorem smul_mem_smul {r} {n} (hr : r ∈ I) (hn : n ∈ N) : r • n ∈ I • N :=
apply_mem_map₂ _ hr hn
#align submodule.smul_mem_smul Submodule.smul_mem_smul
theorem smul_le {P : Submodule R M} : I • N ≤ P ↔ ∀ r ∈ I, ∀ n ∈ N, r • n ∈ P :=
map₂_le
#align submodule.smul_le Submodule.smul_le
@[simp, norm_cast]
lemma coe_set_smul : (I : Set R) • N = I • N :=
Submodule.set_smul_eq_of_le _ _ _
(fun _ _ hr hx => smul_mem_smul hr hx)
(smul_le.mpr fun _ hr _ hx => mem_set_smul_of_mem_mem hr hx)
@[elab_as_elim]
theorem smul_induction_on {p : M → Prop} {x} (H : x ∈ I • N) (smul : ∀ r ∈ I, ∀ n ∈ N, p (r • n))
(add : ∀ x y, p x → p y → p (x + y)) : p x := by
have H0 : p 0 := by simpa only [zero_smul] using smul 0 I.zero_mem 0 N.zero_mem
refine Submodule.iSup_induction (x := x) _ H ?_ H0 add
rintro ⟨i, hi⟩ m ⟨j, hj, hj'⟩
rw [← hj']
exact smul _ hi _ hj
#align submodule.smul_induction_on Submodule.smul_induction_on
@[elab_as_elim]
theorem smul_induction_on' {x : M} (hx : x ∈ I • N) {p : ∀ x, x ∈ I • N → Prop}
(smul : ∀ (r : R) (hr : r ∈ I) (n : M) (hn : n ∈ N), p (r • n) (smul_mem_smul hr hn))
(add : ∀ x hx y hy, p x hx → p y hy → p (x + y) (Submodule.add_mem _ ‹_› ‹_›)) : p x hx := by
refine Exists.elim ?_ fun (h : x ∈ I • N) (H : p x h) => H
exact
smul_induction_on hx (fun a ha x hx => ⟨_, smul _ ha _ hx⟩) fun x y ⟨_, hx⟩ ⟨_, hy⟩ =>
⟨_, add _ _ _ _ hx hy⟩
#align submodule.smul_induction_on' Submodule.smul_induction_on'
theorem mem_smul_span_singleton {I : Ideal R} {m : M} {x : M} :
x ∈ I • span R ({m} : Set M) ↔ ∃ y ∈ I, y • m = x :=
⟨fun hx =>
smul_induction_on hx
(fun r hri n hnm =>
let ⟨s, hs⟩ := mem_span_singleton.1 hnm
⟨r * s, I.mul_mem_right _ hri, hs ▸ mul_smul r s m⟩)
fun m1 m2 ⟨y1, hyi1, hy1⟩ ⟨y2, hyi2, hy2⟩ =>
⟨y1 + y2, I.add_mem hyi1 hyi2, by rw [add_smul, hy1, hy2]⟩,
fun ⟨y, hyi, hy⟩ => hy ▸ smul_mem_smul hyi (subset_span <| Set.mem_singleton m)⟩
#align submodule.mem_smul_span_singleton Submodule.mem_smul_span_singleton
theorem smul_le_right : I • N ≤ N :=
smul_le.2 fun r _ _ => N.smul_mem r
#align submodule.smul_le_right Submodule.smul_le_right
theorem smul_mono (hij : I ≤ J) (hnp : N ≤ P) : I • N ≤ J • P :=
map₂_le_map₂ hij hnp
#align submodule.smul_mono Submodule.smul_mono
theorem smul_mono_left (h : I ≤ J) : I • N ≤ J • N :=
map₂_le_map₂_left h
#align submodule.smul_mono_left Submodule.smul_mono_left
instance : CovariantClass (Ideal R) (Submodule R M) HSMul.hSMul LE.le :=
⟨fun _ _ => map₂_le_map₂_right⟩
@[deprecated smul_mono_right (since := "2024-03-31")]
protected theorem smul_mono_right (h : N ≤ P) : I • N ≤ I • P :=
_root_.smul_mono_right I h
#align submodule.smul_mono_right Submodule.smul_mono_right
theorem map_le_smul_top (I : Ideal R) (f : R →ₗ[R] M) :
Submodule.map f I ≤ I • (⊤ : Submodule R M) := by
rintro _ ⟨y, hy, rfl⟩
rw [← mul_one y, ← smul_eq_mul, f.map_smul]
exact smul_mem_smul hy mem_top
#align submodule.map_le_smul_top Submodule.map_le_smul_top
@[simp]
theorem annihilator_smul (N : Submodule R M) : annihilator N • N = ⊥ :=
eq_bot_iff.2 (smul_le.2 fun _ => mem_annihilator.1)
#align submodule.annihilator_smul Submodule.annihilator_smul
@[simp]
theorem annihilator_mul (I : Ideal R) : annihilator I * I = ⊥ :=
annihilator_smul I
#align submodule.annihilator_mul Submodule.annihilator_mul
@[simp]
theorem mul_annihilator (I : Ideal R) : I * annihilator I = ⊥ := by rw [mul_comm, annihilator_mul]
#align submodule.mul_annihilator Submodule.mul_annihilator
variable (I J N P)
@[simp]
theorem smul_bot : I • (⊥ : Submodule R M) = ⊥ :=
map₂_bot_right _ _
#align submodule.smul_bot Submodule.smul_bot
@[simp]
theorem bot_smul : (⊥ : Ideal R) • N = ⊥ :=
map₂_bot_left _ _
#align submodule.bot_smul Submodule.bot_smul
@[simp]
theorem top_smul : (⊤ : Ideal R) • N = N :=
le_antisymm smul_le_right fun r hri => one_smul R r ▸ smul_mem_smul mem_top hri
#align submodule.top_smul Submodule.top_smul
theorem smul_sup : I • (N ⊔ P) = I • N ⊔ I • P :=
map₂_sup_right _ _ _ _
#align submodule.smul_sup Submodule.smul_sup
theorem sup_smul : (I ⊔ J) • N = I • N ⊔ J • N :=
map₂_sup_left _ _ _ _
#align submodule.sup_smul Submodule.sup_smul
protected theorem smul_assoc : (I • J) • N = I • J • N :=
le_antisymm
(smul_le.2 fun _ hrsij t htn =>
smul_induction_on hrsij
(fun r hr s hs =>
(@smul_eq_mul R _ r s).symm ▸ smul_smul r s t ▸ smul_mem_smul hr (smul_mem_smul hs htn))
fun x y => (add_smul x y t).symm ▸ Submodule.add_mem _)
(smul_le.2 fun r hr _ hsn =>
suffices J • N ≤ Submodule.comap (r • (LinearMap.id : M →ₗ[R] M)) ((I • J) • N) from this hsn
smul_le.2 fun s hs n hn =>
show r • s • n ∈ (I • J) • N from mul_smul r s n ▸ smul_mem_smul (smul_mem_smul hr hs) hn)
#align submodule.smul_assoc Submodule.smul_assoc
@[deprecated smul_inf_le (since := "2024-03-31")]
protected theorem smul_inf_le (M₁ M₂ : Submodule R M) :
I • (M₁ ⊓ M₂) ≤ I • M₁ ⊓ I • M₂ := smul_inf_le _ _ _
#align submodule.smul_inf_le Submodule.smul_inf_le
theorem smul_iSup {ι : Sort*} {I : Ideal R} {t : ι → Submodule R M} : I • iSup t = ⨆ i, I • t i :=
map₂_iSup_right _ _ _
#align submodule.smul_supr Submodule.smul_iSup
@[deprecated smul_iInf_le (since := "2024-03-31")]
protected theorem smul_iInf_le {ι : Sort*} {I : Ideal R} {t : ι → Submodule R M} :
I • iInf t ≤ ⨅ i, I • t i :=
smul_iInf_le
#align submodule.smul_infi_le Submodule.smul_iInf_le
variable (S : Set R) (T : Set M)
theorem span_smul_span : Ideal.span S • span R T = span R (⋃ (s ∈ S) (t ∈ T), {s • t}) :=
(map₂_span_span _ _ _ _).trans <| congr_arg _ <| Set.image2_eq_iUnion _ _ _
#align submodule.span_smul_span Submodule.span_smul_span
| Mathlib/RingTheory/Ideal/Operations.lean | 274 | 280 | theorem ideal_span_singleton_smul (r : R) (N : Submodule R M) :
(Ideal.span {r} : Ideal R) • N = r • N := by |
have : span R (⋃ (t : M) (_ : t ∈ N), {r • t}) = r • N := by
convert span_eq (r • N)
exact (Set.image_eq_iUnion _ (N : Set M)).symm
conv_lhs => rw [← span_eq N, span_smul_span]
simpa
|
import Mathlib.Analysis.SpecialFunctions.Pow.Real
import Mathlib.Data.Int.Log
#align_import analysis.special_functions.log.base from "leanprover-community/mathlib"@"f23a09ce6d3f367220dc3cecad6b7eb69eb01690"
open Set Filter Function
open Topology
noncomputable section
namespace Real
variable {b x y : ℝ}
-- @[pp_nodot] -- Porting note: removed
noncomputable def logb (b x : ℝ) : ℝ :=
log x / log b
#align real.logb Real.logb
theorem log_div_log : log x / log b = logb b x :=
rfl
#align real.log_div_log Real.log_div_log
@[simp]
theorem logb_zero : logb b 0 = 0 := by simp [logb]
#align real.logb_zero Real.logb_zero
@[simp]
theorem logb_one : logb b 1 = 0 := by simp [logb]
#align real.logb_one Real.logb_one
@[simp]
lemma logb_self_eq_one (hb : 1 < b) : logb b b = 1 :=
div_self (log_pos hb).ne'
lemma logb_self_eq_one_iff : logb b b = 1 ↔ b ≠ 0 ∧ b ≠ 1 ∧ b ≠ -1 :=
Iff.trans ⟨fun h h' => by simp [logb, h'] at h, div_self⟩ log_ne_zero
@[simp]
theorem logb_abs (x : ℝ) : logb b |x| = logb b x := by rw [logb, logb, log_abs]
#align real.logb_abs Real.logb_abs
@[simp]
theorem logb_neg_eq_logb (x : ℝ) : logb b (-x) = logb b x := by
rw [← logb_abs x, ← logb_abs (-x), abs_neg]
#align real.logb_neg_eq_logb Real.logb_neg_eq_logb
theorem logb_mul (hx : x ≠ 0) (hy : y ≠ 0) : logb b (x * y) = logb b x + logb b y := by
simp_rw [logb, log_mul hx hy, add_div]
#align real.logb_mul Real.logb_mul
theorem logb_div (hx : x ≠ 0) (hy : y ≠ 0) : logb b (x / y) = logb b x - logb b y := by
simp_rw [logb, log_div hx hy, sub_div]
#align real.logb_div Real.logb_div
@[simp]
theorem logb_inv (x : ℝ) : logb b x⁻¹ = -logb b x := by simp [logb, neg_div]
#align real.logb_inv Real.logb_inv
| Mathlib/Analysis/SpecialFunctions/Log/Base.lean | 84 | 84 | theorem inv_logb (a b : ℝ) : (logb a b)⁻¹ = logb b a := by | simp_rw [logb, inv_div]
|
import Mathlib.Analysis.SpecialFunctions.Exp
import Mathlib.Data.Nat.Factorization.Basic
import Mathlib.Analysis.NormedSpace.Real
#align_import analysis.special_functions.log.basic from "leanprover-community/mathlib"@"f23a09ce6d3f367220dc3cecad6b7eb69eb01690"
open Set Filter Function
open Topology
noncomputable section
namespace Real
variable {x y : ℝ}
-- @[pp_nodot] -- Porting note: removed
noncomputable def log (x : ℝ) : ℝ :=
if hx : x = 0 then 0 else expOrderIso.symm ⟨|x|, abs_pos.2 hx⟩
#align real.log Real.log
theorem log_of_ne_zero (hx : x ≠ 0) : log x = expOrderIso.symm ⟨|x|, abs_pos.2 hx⟩ :=
dif_neg hx
#align real.log_of_ne_zero Real.log_of_ne_zero
theorem log_of_pos (hx : 0 < x) : log x = expOrderIso.symm ⟨x, hx⟩ := by
rw [log_of_ne_zero hx.ne']
congr
exact abs_of_pos hx
#align real.log_of_pos Real.log_of_pos
theorem exp_log_eq_abs (hx : x ≠ 0) : exp (log x) = |x| := by
rw [log_of_ne_zero hx, ← coe_expOrderIso_apply, OrderIso.apply_symm_apply, Subtype.coe_mk]
#align real.exp_log_eq_abs Real.exp_log_eq_abs
theorem exp_log (hx : 0 < x) : exp (log x) = x := by
rw [exp_log_eq_abs hx.ne']
exact abs_of_pos hx
#align real.exp_log Real.exp_log
theorem exp_log_of_neg (hx : x < 0) : exp (log x) = -x := by
rw [exp_log_eq_abs (ne_of_lt hx)]
exact abs_of_neg hx
#align real.exp_log_of_neg Real.exp_log_of_neg
theorem le_exp_log (x : ℝ) : x ≤ exp (log x) := by
by_cases h_zero : x = 0
· rw [h_zero, log, dif_pos rfl, exp_zero]
exact zero_le_one
· rw [exp_log_eq_abs h_zero]
exact le_abs_self _
#align real.le_exp_log Real.le_exp_log
@[simp]
theorem log_exp (x : ℝ) : log (exp x) = x :=
exp_injective <| exp_log (exp_pos x)
#align real.log_exp Real.log_exp
theorem surjOn_log : SurjOn log (Ioi 0) univ := fun x _ => ⟨exp x, exp_pos x, log_exp x⟩
#align real.surj_on_log Real.surjOn_log
theorem log_surjective : Surjective log := fun x => ⟨exp x, log_exp x⟩
#align real.log_surjective Real.log_surjective
@[simp]
theorem range_log : range log = univ :=
log_surjective.range_eq
#align real.range_log Real.range_log
@[simp]
theorem log_zero : log 0 = 0 :=
dif_pos rfl
#align real.log_zero Real.log_zero
@[simp]
theorem log_one : log 1 = 0 :=
exp_injective <| by rw [exp_log zero_lt_one, exp_zero]
#align real.log_one Real.log_one
@[simp]
theorem log_abs (x : ℝ) : log |x| = log x := by
by_cases h : x = 0
· simp [h]
· rw [← exp_eq_exp, exp_log_eq_abs h, exp_log_eq_abs (abs_pos.2 h).ne', abs_abs]
#align real.log_abs Real.log_abs
@[simp]
theorem log_neg_eq_log (x : ℝ) : log (-x) = log x := by rw [← log_abs x, ← log_abs (-x), abs_neg]
#align real.log_neg_eq_log Real.log_neg_eq_log
theorem sinh_log {x : ℝ} (hx : 0 < x) : sinh (log x) = (x - x⁻¹) / 2 := by
rw [sinh_eq, exp_neg, exp_log hx]
#align real.sinh_log Real.sinh_log
theorem cosh_log {x : ℝ} (hx : 0 < x) : cosh (log x) = (x + x⁻¹) / 2 := by
rw [cosh_eq, exp_neg, exp_log hx]
#align real.cosh_log Real.cosh_log
theorem surjOn_log' : SurjOn log (Iio 0) univ := fun x _ =>
⟨-exp x, neg_lt_zero.2 <| exp_pos x, by rw [log_neg_eq_log, log_exp]⟩
#align real.surj_on_log' Real.surjOn_log'
theorem log_mul (hx : x ≠ 0) (hy : y ≠ 0) : log (x * y) = log x + log y :=
exp_injective <| by
rw [exp_log_eq_abs (mul_ne_zero hx hy), exp_add, exp_log_eq_abs hx, exp_log_eq_abs hy, abs_mul]
#align real.log_mul Real.log_mul
theorem log_div (hx : x ≠ 0) (hy : y ≠ 0) : log (x / y) = log x - log y :=
exp_injective <| by
rw [exp_log_eq_abs (div_ne_zero hx hy), exp_sub, exp_log_eq_abs hx, exp_log_eq_abs hy, abs_div]
#align real.log_div Real.log_div
@[simp]
theorem log_inv (x : ℝ) : log x⁻¹ = -log x := by
by_cases hx : x = 0; · simp [hx]
rw [← exp_eq_exp, exp_log_eq_abs (inv_ne_zero hx), exp_neg, exp_log_eq_abs hx, abs_inv]
#align real.log_inv Real.log_inv
theorem log_le_log_iff (h : 0 < x) (h₁ : 0 < y) : log x ≤ log y ↔ x ≤ y := by
rw [← exp_le_exp, exp_log h, exp_log h₁]
#align real.log_le_log Real.log_le_log_iff
@[gcongr]
lemma log_le_log (hx : 0 < x) (hxy : x ≤ y) : log x ≤ log y :=
(log_le_log_iff hx (hx.trans_le hxy)).2 hxy
@[gcongr]
theorem log_lt_log (hx : 0 < x) (h : x < y) : log x < log y := by
rwa [← exp_lt_exp, exp_log hx, exp_log (lt_trans hx h)]
#align real.log_lt_log Real.log_lt_log
theorem log_lt_log_iff (hx : 0 < x) (hy : 0 < y) : log x < log y ↔ x < y := by
rw [← exp_lt_exp, exp_log hx, exp_log hy]
#align real.log_lt_log_iff Real.log_lt_log_iff
theorem log_le_iff_le_exp (hx : 0 < x) : log x ≤ y ↔ x ≤ exp y := by rw [← exp_le_exp, exp_log hx]
#align real.log_le_iff_le_exp Real.log_le_iff_le_exp
theorem log_lt_iff_lt_exp (hx : 0 < x) : log x < y ↔ x < exp y := by rw [← exp_lt_exp, exp_log hx]
#align real.log_lt_iff_lt_exp Real.log_lt_iff_lt_exp
theorem le_log_iff_exp_le (hy : 0 < y) : x ≤ log y ↔ exp x ≤ y := by rw [← exp_le_exp, exp_log hy]
#align real.le_log_iff_exp_le Real.le_log_iff_exp_le
theorem lt_log_iff_exp_lt (hy : 0 < y) : x < log y ↔ exp x < y := by rw [← exp_lt_exp, exp_log hy]
#align real.lt_log_iff_exp_lt Real.lt_log_iff_exp_lt
theorem log_pos_iff (hx : 0 < x) : 0 < log x ↔ 1 < x := by
rw [← log_one]
exact log_lt_log_iff zero_lt_one hx
#align real.log_pos_iff Real.log_pos_iff
theorem log_pos (hx : 1 < x) : 0 < log x :=
(log_pos_iff (lt_trans zero_lt_one hx)).2 hx
#align real.log_pos Real.log_pos
theorem log_pos_of_lt_neg_one (hx : x < -1) : 0 < log x := by
rw [← neg_neg x, log_neg_eq_log]
have : 1 < -x := by linarith
exact log_pos this
theorem log_neg_iff (h : 0 < x) : log x < 0 ↔ x < 1 := by
rw [← log_one]
exact log_lt_log_iff h zero_lt_one
#align real.log_neg_iff Real.log_neg_iff
theorem log_neg (h0 : 0 < x) (h1 : x < 1) : log x < 0 :=
(log_neg_iff h0).2 h1
#align real.log_neg Real.log_neg
theorem log_neg_of_lt_zero (h0 : x < 0) (h1 : -1 < x) : log x < 0 := by
rw [← neg_neg x, log_neg_eq_log]
have h0' : 0 < -x := by linarith
have h1' : -x < 1 := by linarith
exact log_neg h0' h1'
theorem log_nonneg_iff (hx : 0 < x) : 0 ≤ log x ↔ 1 ≤ x := by rw [← not_lt, log_neg_iff hx, not_lt]
#align real.log_nonneg_iff Real.log_nonneg_iff
theorem log_nonneg (hx : 1 ≤ x) : 0 ≤ log x :=
(log_nonneg_iff (zero_lt_one.trans_le hx)).2 hx
#align real.log_nonneg Real.log_nonneg
theorem log_nonpos_iff (hx : 0 < x) : log x ≤ 0 ↔ x ≤ 1 := by rw [← not_lt, log_pos_iff hx, not_lt]
#align real.log_nonpos_iff Real.log_nonpos_iff
theorem log_nonpos_iff' (hx : 0 ≤ x) : log x ≤ 0 ↔ x ≤ 1 := by
rcases hx.eq_or_lt with (rfl | hx)
· simp [le_refl, zero_le_one]
exact log_nonpos_iff hx
#align real.log_nonpos_iff' Real.log_nonpos_iff'
theorem log_nonpos (hx : 0 ≤ x) (h'x : x ≤ 1) : log x ≤ 0 :=
(log_nonpos_iff' hx).2 h'x
#align real.log_nonpos Real.log_nonpos
theorem log_natCast_nonneg (n : ℕ) : 0 ≤ log n := by
if hn : n = 0 then
simp [hn]
else
have : (1 : ℝ) ≤ n := mod_cast Nat.one_le_of_lt <| Nat.pos_of_ne_zero hn
exact log_nonneg this
@[deprecated (since := "2024-04-17")]
alias log_nat_cast_nonneg := log_natCast_nonneg
theorem log_neg_natCast_nonneg (n : ℕ) : 0 ≤ log (-n) := by
rw [← log_neg_eq_log, neg_neg]
exact log_natCast_nonneg _
@[deprecated (since := "2024-04-17")]
alias log_neg_nat_cast_nonneg := log_neg_natCast_nonneg
| Mathlib/Analysis/SpecialFunctions/Log/Basic.lean | 237 | 248 | theorem log_intCast_nonneg (n : ℤ) : 0 ≤ log n := by |
cases lt_trichotomy 0 n with
| inl hn =>
have : (1 : ℝ) ≤ n := mod_cast hn
exact log_nonneg this
| inr hn =>
cases hn with
| inl hn => simp [hn.symm]
| inr hn =>
have : (1 : ℝ) ≤ -n := by rw [← neg_zero, ← lt_neg] at hn; exact mod_cast hn
rw [← log_neg_eq_log]
exact log_nonneg this
|
import Mathlib.AlgebraicTopology.DoldKan.Homotopies
import Mathlib.Tactic.Ring
#align_import algebraic_topology.dold_kan.faces from "leanprover-community/mathlib"@"32a7e535287f9c73f2e4d2aef306a39190f0b504"
open CategoryTheory CategoryTheory.Limits CategoryTheory.Category
CategoryTheory.Preadditive CategoryTheory.SimplicialObject Simplicial
namespace AlgebraicTopology
namespace DoldKan
variable {C : Type*} [Category C] [Preadditive C]
variable {X : SimplicialObject C}
def HigherFacesVanish {Y : C} {n : ℕ} (q : ℕ) (φ : Y ⟶ X _[n + 1]) : Prop :=
∀ j : Fin (n + 1), n + 1 ≤ (j : ℕ) + q → φ ≫ X.δ j.succ = 0
#align algebraic_topology.dold_kan.higher_faces_vanish AlgebraicTopology.DoldKan.HigherFacesVanish
namespace HigherFacesVanish
@[reassoc]
| Mathlib/AlgebraicTopology/DoldKan/Faces.lean | 53 | 58 | theorem comp_δ_eq_zero {Y : C} {n : ℕ} {q : ℕ} {φ : Y ⟶ X _[n + 1]} (v : HigherFacesVanish q φ)
(j : Fin (n + 2)) (hj₁ : j ≠ 0) (hj₂ : n + 2 ≤ (j : ℕ) + q) : φ ≫ X.δ j = 0 := by |
obtain ⟨i, rfl⟩ := Fin.eq_succ_of_ne_zero hj₁
apply v i
simp only [Fin.val_succ] at hj₂
omega
|
import Mathlib.Algebra.Group.Subgroup.Basic
import Mathlib.Algebra.Module.Defs
import Mathlib.Algebra.Star.Pi
#align_import algebra.star.self_adjoint from "leanprover-community/mathlib"@"a6ece35404f60597c651689c1b46ead86de5ac1b"
open Function
variable {R A : Type*}
def IsSelfAdjoint [Star R] (x : R) : Prop :=
star x = x
#align is_self_adjoint IsSelfAdjoint
@[mk_iff]
class IsStarNormal [Mul R] [Star R] (x : R) : Prop where
star_comm_self : Commute (star x) x
#align is_star_normal IsStarNormal
export IsStarNormal (star_comm_self)
theorem star_comm_self' [Mul R] [Star R] (x : R) [IsStarNormal x] : star x * x = x * star x :=
IsStarNormal.star_comm_self
#align star_comm_self' star_comm_self'
namespace IsSelfAdjoint
-- named to match `Commute.allₓ`
theorem all [Star R] [TrivialStar R] (r : R) : IsSelfAdjoint r :=
star_trivial _
#align is_self_adjoint.all IsSelfAdjoint.all
theorem star_eq [Star R] {x : R} (hx : IsSelfAdjoint x) : star x = x :=
hx
#align is_self_adjoint.star_eq IsSelfAdjoint.star_eq
theorem _root_.isSelfAdjoint_iff [Star R] {x : R} : IsSelfAdjoint x ↔ star x = x :=
Iff.rfl
#align is_self_adjoint_iff isSelfAdjoint_iff
@[simp]
theorem star_iff [InvolutiveStar R] {x : R} : IsSelfAdjoint (star x) ↔ IsSelfAdjoint x := by
simpa only [IsSelfAdjoint, star_star] using eq_comm
#align is_self_adjoint.star_iff IsSelfAdjoint.star_iff
@[simp]
theorem star_mul_self [Mul R] [StarMul R] (x : R) : IsSelfAdjoint (star x * x) := by
simp only [IsSelfAdjoint, star_mul, star_star]
#align is_self_adjoint.star_mul_self IsSelfAdjoint.star_mul_self
@[simp]
theorem mul_star_self [Mul R] [StarMul R] (x : R) : IsSelfAdjoint (x * star x) := by
simpa only [star_star] using star_mul_self (star x)
#align is_self_adjoint.mul_star_self IsSelfAdjoint.mul_star_self
lemma commute_iff {R : Type*} [Mul R] [StarMul R] {x y : R}
(hx : IsSelfAdjoint x) (hy : IsSelfAdjoint y) : Commute x y ↔ IsSelfAdjoint (x * y) := by
refine ⟨fun h ↦ ?_, fun h ↦ ?_⟩
· rw [isSelfAdjoint_iff, star_mul, hx.star_eq, hy.star_eq, h.eq]
· simpa only [star_mul, hx.star_eq, hy.star_eq] using h.symm
theorem starHom_apply {F R S : Type*} [Star R] [Star S] [FunLike F R S] [StarHomClass F R S]
{x : R} (hx : IsSelfAdjoint x) (f : F) : IsSelfAdjoint (f x) :=
show star (f x) = f x from map_star f x ▸ congr_arg f hx
#align is_self_adjoint.star_hom_apply IsSelfAdjoint.starHom_apply
theorem _root_.isSelfAdjoint_starHom_apply {F R S : Type*} [Star R] [Star S] [FunLike F R S]
[StarHomClass F R S] [TrivialStar R] (f : F) (x : R) : IsSelfAdjoint (f x) :=
(IsSelfAdjoint.all x).starHom_apply f
section Semifield
variable [Semifield R] [StarRing R]
| Mathlib/Algebra/Star/SelfAdjoint.lean | 280 | 281 | theorem div {x y : R} (hx : IsSelfAdjoint x) (hy : IsSelfAdjoint y) : IsSelfAdjoint (x / y) := by |
simp only [isSelfAdjoint_iff, star_div', hx.star_eq, hy.star_eq]
|
import Mathlib.Order.Interval.Multiset
#align_import data.nat.interval from "leanprover-community/mathlib"@"1d29de43a5ba4662dd33b5cfeecfc2a27a5a8a29"
-- TODO
-- assert_not_exists Ring
open Finset Nat
variable (a b c : ℕ)
namespace Nat
instance instLocallyFiniteOrder : LocallyFiniteOrder ℕ where
finsetIcc a b := ⟨List.range' a (b + 1 - a), List.nodup_range' _ _⟩
finsetIco a b := ⟨List.range' a (b - a), List.nodup_range' _ _⟩
finsetIoc a b := ⟨List.range' (a + 1) (b - a), List.nodup_range' _ _⟩
finsetIoo a b := ⟨List.range' (a + 1) (b - a - 1), List.nodup_range' _ _⟩
finset_mem_Icc a b x := by rw [Finset.mem_mk, Multiset.mem_coe, List.mem_range'_1]; omega
finset_mem_Ico a b x := by rw [Finset.mem_mk, Multiset.mem_coe, List.mem_range'_1]; omega
finset_mem_Ioc a b x := by rw [Finset.mem_mk, Multiset.mem_coe, List.mem_range'_1]; omega
finset_mem_Ioo a b x := by rw [Finset.mem_mk, Multiset.mem_coe, List.mem_range'_1]; omega
theorem Icc_eq_range' : Icc a b = ⟨List.range' a (b + 1 - a), List.nodup_range' _ _⟩ :=
rfl
#align nat.Icc_eq_range' Nat.Icc_eq_range'
theorem Ico_eq_range' : Ico a b = ⟨List.range' a (b - a), List.nodup_range' _ _⟩ :=
rfl
#align nat.Ico_eq_range' Nat.Ico_eq_range'
theorem Ioc_eq_range' : Ioc a b = ⟨List.range' (a + 1) (b - a), List.nodup_range' _ _⟩ :=
rfl
#align nat.Ioc_eq_range' Nat.Ioc_eq_range'
theorem Ioo_eq_range' : Ioo a b = ⟨List.range' (a + 1) (b - a - 1), List.nodup_range' _ _⟩ :=
rfl
#align nat.Ioo_eq_range' Nat.Ioo_eq_range'
theorem uIcc_eq_range' :
uIcc a b = ⟨List.range' (min a b) (max a b + 1 - min a b), List.nodup_range' _ _⟩ := rfl
#align nat.uIcc_eq_range' Nat.uIcc_eq_range'
theorem Iio_eq_range : Iio = range := by
ext b x
rw [mem_Iio, mem_range]
#align nat.Iio_eq_range Nat.Iio_eq_range
@[simp]
theorem Ico_zero_eq_range : Ico 0 = range := by rw [← Nat.bot_eq_zero, ← Iio_eq_Ico, Iio_eq_range]
#align nat.Ico_zero_eq_range Nat.Ico_zero_eq_range
lemma range_eq_Icc_zero_sub_one (n : ℕ) (hn : n ≠ 0): range n = Icc 0 (n - 1) := by
ext b
simp_all only [mem_Icc, zero_le, true_and, mem_range]
exact lt_iff_le_pred (zero_lt_of_ne_zero hn)
theorem _root_.Finset.range_eq_Ico : range = Ico 0 :=
Ico_zero_eq_range.symm
#align finset.range_eq_Ico Finset.range_eq_Ico
@[simp]
theorem card_Icc : (Icc a b).card = b + 1 - a :=
List.length_range' _ _ _
#align nat.card_Icc Nat.card_Icc
@[simp]
theorem card_Ico : (Ico a b).card = b - a :=
List.length_range' _ _ _
#align nat.card_Ico Nat.card_Ico
@[simp]
theorem card_Ioc : (Ioc a b).card = b - a :=
List.length_range' _ _ _
#align nat.card_Ioc Nat.card_Ioc
@[simp]
theorem card_Ioo : (Ioo a b).card = b - a - 1 :=
List.length_range' _ _ _
#align nat.card_Ioo Nat.card_Ioo
@[simp]
theorem card_uIcc : (uIcc a b).card = (b - a : ℤ).natAbs + 1 :=
(card_Icc _ _).trans $ by rw [← Int.natCast_inj, sup_eq_max, inf_eq_min, Int.ofNat_sub] <;> omega
#align nat.card_uIcc Nat.card_uIcc
@[simp]
lemma card_Iic : (Iic b).card = b + 1 := by rw [Iic_eq_Icc, card_Icc, Nat.bot_eq_zero, Nat.sub_zero]
#align nat.card_Iic Nat.card_Iic
@[simp]
theorem card_Iio : (Iio b).card = b := by rw [Iio_eq_Ico, card_Ico, Nat.bot_eq_zero, Nat.sub_zero]
#align nat.card_Iio Nat.card_Iio
-- Porting note (#10618): simp can prove this
-- @[simp]
theorem card_fintypeIcc : Fintype.card (Set.Icc a b) = b + 1 - a := by
rw [Fintype.card_ofFinset, card_Icc]
#align nat.card_fintype_Icc Nat.card_fintypeIcc
-- Porting note (#10618): simp can prove this
-- @[simp]
theorem card_fintypeIco : Fintype.card (Set.Ico a b) = b - a := by
rw [Fintype.card_ofFinset, card_Ico]
#align nat.card_fintype_Ico Nat.card_fintypeIco
-- Porting note (#10618): simp can prove this
-- @[simp]
theorem card_fintypeIoc : Fintype.card (Set.Ioc a b) = b - a := by
rw [Fintype.card_ofFinset, card_Ioc]
#align nat.card_fintype_Ioc Nat.card_fintypeIoc
-- Porting note (#10618): simp can prove this
-- @[simp]
theorem card_fintypeIoo : Fintype.card (Set.Ioo a b) = b - a - 1 := by
rw [Fintype.card_ofFinset, card_Ioo]
#align nat.card_fintype_Ioo Nat.card_fintypeIoo
-- Porting note (#10618): simp can prove this
-- @[simp]
theorem card_fintypeIic : Fintype.card (Set.Iic b) = b + 1 := by
rw [Fintype.card_ofFinset, card_Iic]
#align nat.card_fintype_Iic Nat.card_fintypeIic
-- Porting note (#10618): simp can prove this
-- @[simp]
theorem card_fintypeIio : Fintype.card (Set.Iio b) = b := by rw [Fintype.card_ofFinset, card_Iio]
#align nat.card_fintype_Iio Nat.card_fintypeIio
-- TODO@Yaël: Generalize all the following lemmas to `SuccOrder`
theorem Icc_succ_left : Icc a.succ b = Ioc a b := by
ext x
rw [mem_Icc, mem_Ioc, succ_le_iff]
#align nat.Icc_succ_left Nat.Icc_succ_left
theorem Ico_succ_right : Ico a b.succ = Icc a b := by
ext x
rw [mem_Ico, mem_Icc, Nat.lt_succ_iff]
#align nat.Ico_succ_right Nat.Ico_succ_right
theorem Ico_succ_left : Ico a.succ b = Ioo a b := by
ext x
rw [mem_Ico, mem_Ioo, succ_le_iff]
#align nat.Ico_succ_left Nat.Ico_succ_left
theorem Icc_pred_right {b : ℕ} (h : 0 < b) : Icc a (b - 1) = Ico a b := by
ext x
rw [mem_Icc, mem_Ico, lt_iff_le_pred h]
#align nat.Icc_pred_right Nat.Icc_pred_right
theorem Ico_succ_succ : Ico a.succ b.succ = Ioc a b := by
ext x
rw [mem_Ico, mem_Ioc, succ_le_iff, Nat.lt_succ_iff]
#align nat.Ico_succ_succ Nat.Ico_succ_succ
@[simp]
theorem Ico_succ_singleton : Ico a (a + 1) = {a} := by rw [Ico_succ_right, Icc_self]
#align nat.Ico_succ_singleton Nat.Ico_succ_singleton
@[simp]
theorem Ico_pred_singleton {a : ℕ} (h : 0 < a) : Ico (a - 1) a = {a - 1} := by
rw [← Icc_pred_right _ h, Icc_self]
#align nat.Ico_pred_singleton Nat.Ico_pred_singleton
@[simp]
theorem Ioc_succ_singleton : Ioc b (b + 1) = {b + 1} := by rw [← Nat.Icc_succ_left, Icc_self]
#align nat.Ioc_succ_singleton Nat.Ioc_succ_singleton
variable {a b c}
theorem Ico_succ_right_eq_insert_Ico (h : a ≤ b) : Ico a (b + 1) = insert b (Ico a b) := by
rw [Ico_succ_right, ← Ico_insert_right h]
#align nat.Ico_succ_right_eq_insert_Ico Nat.Ico_succ_right_eq_insert_Ico
theorem Ico_insert_succ_left (h : a < b) : insert a (Ico a.succ b) = Ico a b := by
rw [Ico_succ_left, ← Ioo_insert_left h]
#align nat.Ico_insert_succ_left Nat.Ico_insert_succ_left
| Mathlib/Order/Interval/Finset/Nat.lean | 196 | 202 | theorem image_sub_const_Ico (h : c ≤ a) :
((Ico a b).image fun x => x - c) = Ico (a - c) (b - c) := by |
ext x
simp_rw [mem_image, mem_Ico]
refine ⟨?_, fun h ↦ ⟨x + c, by omega⟩⟩
rintro ⟨x, hx, rfl⟩
omega
|
import Mathlib.Data.Matrix.Basic
import Mathlib.Data.Matrix.Block
import Mathlib.LinearAlgebra.Matrix.Determinant.Basic
import Mathlib.LinearAlgebra.Matrix.NonsingularInverse
import Mathlib.LinearAlgebra.TensorProduct.Basic
import Mathlib.RingTheory.TensorProduct.Basic
#align_import data.matrix.kronecker from "leanprover-community/mathlib"@"3e068ece210655b7b9a9477c3aff38a492400aa1"
namespace Matrix
open Matrix
open scoped RightActions
variable {R α α' β β' γ γ' : Type*}
variable {l m n p : Type*} {q r : Type*} {l' m' n' p' : Type*}
section KroneckerMap
def kroneckerMap (f : α → β → γ) (A : Matrix l m α) (B : Matrix n p β) : Matrix (l × n) (m × p) γ :=
of fun (i : l × n) (j : m × p) => f (A i.1 j.1) (B i.2 j.2)
#align matrix.kronecker_map Matrix.kroneckerMap
-- TODO: set as an equation lemma for `kroneckerMap`, see mathlib4#3024
@[simp]
theorem kroneckerMap_apply (f : α → β → γ) (A : Matrix l m α) (B : Matrix n p β) (i j) :
kroneckerMap f A B i j = f (A i.1 j.1) (B i.2 j.2) :=
rfl
#align matrix.kronecker_map_apply Matrix.kroneckerMap_apply
theorem kroneckerMap_transpose (f : α → β → γ) (A : Matrix l m α) (B : Matrix n p β) :
kroneckerMap f Aᵀ Bᵀ = (kroneckerMap f A B)ᵀ :=
ext fun _ _ => rfl
#align matrix.kronecker_map_transpose Matrix.kroneckerMap_transpose
theorem kroneckerMap_map_left (f : α' → β → γ) (g : α → α') (A : Matrix l m α) (B : Matrix n p β) :
kroneckerMap f (A.map g) B = kroneckerMap (fun a b => f (g a) b) A B :=
ext fun _ _ => rfl
#align matrix.kronecker_map_map_left Matrix.kroneckerMap_map_left
theorem kroneckerMap_map_right (f : α → β' → γ) (g : β → β') (A : Matrix l m α) (B : Matrix n p β) :
kroneckerMap f A (B.map g) = kroneckerMap (fun a b => f a (g b)) A B :=
ext fun _ _ => rfl
#align matrix.kronecker_map_map_right Matrix.kroneckerMap_map_right
theorem kroneckerMap_map (f : α → β → γ) (g : γ → γ') (A : Matrix l m α) (B : Matrix n p β) :
(kroneckerMap f A B).map g = kroneckerMap (fun a b => g (f a b)) A B :=
ext fun _ _ => rfl
#align matrix.kronecker_map_map Matrix.kroneckerMap_map
@[simp]
theorem kroneckerMap_zero_left [Zero α] [Zero γ] (f : α → β → γ) (hf : ∀ b, f 0 b = 0)
(B : Matrix n p β) : kroneckerMap f (0 : Matrix l m α) B = 0 :=
ext fun _ _ => hf _
#align matrix.kronecker_map_zero_left Matrix.kroneckerMap_zero_left
@[simp]
theorem kroneckerMap_zero_right [Zero β] [Zero γ] (f : α → β → γ) (hf : ∀ a, f a 0 = 0)
(A : Matrix l m α) : kroneckerMap f A (0 : Matrix n p β) = 0 :=
ext fun _ _ => hf _
#align matrix.kronecker_map_zero_right Matrix.kroneckerMap_zero_right
theorem kroneckerMap_add_left [Add α] [Add γ] (f : α → β → γ)
(hf : ∀ a₁ a₂ b, f (a₁ + a₂) b = f a₁ b + f a₂ b) (A₁ A₂ : Matrix l m α) (B : Matrix n p β) :
kroneckerMap f (A₁ + A₂) B = kroneckerMap f A₁ B + kroneckerMap f A₂ B :=
ext fun _ _ => hf _ _ _
#align matrix.kronecker_map_add_left Matrix.kroneckerMap_add_left
theorem kroneckerMap_add_right [Add β] [Add γ] (f : α → β → γ)
(hf : ∀ a b₁ b₂, f a (b₁ + b₂) = f a b₁ + f a b₂) (A : Matrix l m α) (B₁ B₂ : Matrix n p β) :
kroneckerMap f A (B₁ + B₂) = kroneckerMap f A B₁ + kroneckerMap f A B₂ :=
ext fun _ _ => hf _ _ _
#align matrix.kronecker_map_add_right Matrix.kroneckerMap_add_right
theorem kroneckerMap_smul_left [SMul R α] [SMul R γ] (f : α → β → γ) (r : R)
(hf : ∀ a b, f (r • a) b = r • f a b) (A : Matrix l m α) (B : Matrix n p β) :
kroneckerMap f (r • A) B = r • kroneckerMap f A B :=
ext fun _ _ => hf _ _
#align matrix.kronecker_map_smul_left Matrix.kroneckerMap_smul_left
theorem kroneckerMap_smul_right [SMul R β] [SMul R γ] (f : α → β → γ) (r : R)
(hf : ∀ a b, f a (r • b) = r • f a b) (A : Matrix l m α) (B : Matrix n p β) :
kroneckerMap f A (r • B) = r • kroneckerMap f A B :=
ext fun _ _ => hf _ _
#align matrix.kronecker_map_smul_right Matrix.kroneckerMap_smul_right
theorem kroneckerMap_diagonal_diagonal [Zero α] [Zero β] [Zero γ] [DecidableEq m] [DecidableEq n]
(f : α → β → γ) (hf₁ : ∀ b, f 0 b = 0) (hf₂ : ∀ a, f a 0 = 0) (a : m → α) (b : n → β) :
kroneckerMap f (diagonal a) (diagonal b) = diagonal fun mn => f (a mn.1) (b mn.2) := by
ext ⟨i₁, i₂⟩ ⟨j₁, j₂⟩
simp [diagonal, apply_ite f, ite_and, ite_apply, apply_ite (f (a i₁)), hf₁, hf₂]
#align matrix.kronecker_map_diagonal_diagonal Matrix.kroneckerMap_diagonal_diagonal
theorem kroneckerMap_diagonal_right [Zero β] [Zero γ] [DecidableEq n] (f : α → β → γ)
(hf : ∀ a, f a 0 = 0) (A : Matrix l m α) (b : n → β) :
kroneckerMap f A (diagonal b) = blockDiagonal fun i => A.map fun a => f a (b i) := by
ext ⟨i₁, i₂⟩ ⟨j₁, j₂⟩
simp [diagonal, blockDiagonal, apply_ite (f (A i₁ j₁)), hf]
#align matrix.kronecker_map_diagonal_right Matrix.kroneckerMap_diagonal_right
theorem kroneckerMap_diagonal_left [Zero α] [Zero γ] [DecidableEq l] (f : α → β → γ)
(hf : ∀ b, f 0 b = 0) (a : l → α) (B : Matrix m n β) :
kroneckerMap f (diagonal a) B =
Matrix.reindex (Equiv.prodComm _ _) (Equiv.prodComm _ _)
(blockDiagonal fun i => B.map fun b => f (a i) b) := by
ext ⟨i₁, i₂⟩ ⟨j₁, j₂⟩
simp [diagonal, blockDiagonal, apply_ite f, ite_apply, hf]
#align matrix.kronecker_map_diagonal_left Matrix.kroneckerMap_diagonal_left
@[simp]
theorem kroneckerMap_one_one [Zero α] [Zero β] [Zero γ] [One α] [One β] [One γ] [DecidableEq m]
[DecidableEq n] (f : α → β → γ) (hf₁ : ∀ b, f 0 b = 0) (hf₂ : ∀ a, f a 0 = 0)
(hf₃ : f 1 1 = 1) : kroneckerMap f (1 : Matrix m m α) (1 : Matrix n n β) = 1 :=
(kroneckerMap_diagonal_diagonal _ hf₁ hf₂ _ _).trans <| by simp only [hf₃, diagonal_one]
#align matrix.kronecker_map_one_one Matrix.kroneckerMap_one_one
theorem kroneckerMap_reindex (f : α → β → γ) (el : l ≃ l') (em : m ≃ m') (en : n ≃ n') (ep : p ≃ p')
(M : Matrix l m α) (N : Matrix n p β) :
kroneckerMap f (reindex el em M) (reindex en ep N) =
reindex (el.prodCongr en) (em.prodCongr ep) (kroneckerMap f M N) := by
ext ⟨i, i'⟩ ⟨j, j'⟩
rfl
#align matrix.kronecker_map_reindex Matrix.kroneckerMap_reindex
theorem kroneckerMap_reindex_left (f : α → β → γ) (el : l ≃ l') (em : m ≃ m') (M : Matrix l m α)
(N : Matrix n n' β) :
kroneckerMap f (Matrix.reindex el em M) N =
reindex (el.prodCongr (Equiv.refl _)) (em.prodCongr (Equiv.refl _)) (kroneckerMap f M N) :=
kroneckerMap_reindex _ _ _ (Equiv.refl _) (Equiv.refl _) _ _
#align matrix.kronecker_map_reindex_left Matrix.kroneckerMap_reindex_left
theorem kroneckerMap_reindex_right (f : α → β → γ) (em : m ≃ m') (en : n ≃ n') (M : Matrix l l' α)
(N : Matrix m n β) :
kroneckerMap f M (reindex em en N) =
reindex ((Equiv.refl _).prodCongr em) ((Equiv.refl _).prodCongr en) (kroneckerMap f M N) :=
kroneckerMap_reindex _ (Equiv.refl _) (Equiv.refl _) _ _ _ _
#align matrix.kronecker_map_reindex_right Matrix.kroneckerMap_reindex_right
theorem kroneckerMap_assoc {δ ξ ω ω' : Type*} (f : α → β → γ) (g : γ → δ → ω) (f' : α → ξ → ω')
(g' : β → δ → ξ) (A : Matrix l m α) (B : Matrix n p β) (D : Matrix q r δ) (φ : ω ≃ ω')
(hφ : ∀ a b d, φ (g (f a b) d) = f' a (g' b d)) :
(reindex (Equiv.prodAssoc l n q) (Equiv.prodAssoc m p r)).trans (Equiv.mapMatrix φ)
(kroneckerMap g (kroneckerMap f A B) D) =
kroneckerMap f' A (kroneckerMap g' B D) :=
ext fun _ _ => hφ _ _ _
#align matrix.kronecker_map_assoc Matrix.kroneckerMap_assoc
theorem kroneckerMap_assoc₁ {δ ξ ω : Type*} (f : α → β → γ) (g : γ → δ → ω) (f' : α → ξ → ω)
(g' : β → δ → ξ) (A : Matrix l m α) (B : Matrix n p β) (D : Matrix q r δ)
(h : ∀ a b d, g (f a b) d = f' a (g' b d)) :
reindex (Equiv.prodAssoc l n q) (Equiv.prodAssoc m p r)
(kroneckerMap g (kroneckerMap f A B) D) =
kroneckerMap f' A (kroneckerMap g' B D) :=
ext fun _ _ => h _ _ _
#align matrix.kronecker_map_assoc₁ Matrix.kroneckerMap_assoc₁
@[simps!]
def kroneckerMapBilinear [CommSemiring R] [AddCommMonoid α] [AddCommMonoid β] [AddCommMonoid γ]
[Module R α] [Module R β] [Module R γ] (f : α →ₗ[R] β →ₗ[R] γ) :
Matrix l m α →ₗ[R] Matrix n p β →ₗ[R] Matrix (l × n) (m × p) γ :=
LinearMap.mk₂ R (kroneckerMap fun r s => f r s) (kroneckerMap_add_left _ <| f.map_add₂)
(fun _ => kroneckerMap_smul_left _ _ <| f.map_smul₂ _)
(kroneckerMap_add_right _ fun a => (f a).map_add) fun r =>
kroneckerMap_smul_right _ _ fun a => (f a).map_smul r
#align matrix.kronecker_map_bilinear Matrix.kroneckerMapBilinear
theorem kroneckerMapBilinear_mul_mul [CommSemiring R] [Fintype m] [Fintype m']
[NonUnitalNonAssocSemiring α] [NonUnitalNonAssocSemiring β] [NonUnitalNonAssocSemiring γ]
[Module R α] [Module R β] [Module R γ] (f : α →ₗ[R] β →ₗ[R] γ)
(h_comm : ∀ a b a' b', f (a * b) (a' * b') = f a a' * f b b') (A : Matrix l m α)
(B : Matrix m n α) (A' : Matrix l' m' β) (B' : Matrix m' n' β) :
kroneckerMapBilinear f (A * B) (A' * B') =
kroneckerMapBilinear f A A' * kroneckerMapBilinear f B B' := by
ext ⟨i, i'⟩ ⟨j, j'⟩
simp only [kroneckerMapBilinear_apply_apply, mul_apply, ← Finset.univ_product_univ,
Finset.sum_product, kroneckerMap_apply]
simp_rw [map_sum f, LinearMap.sum_apply, map_sum, h_comm]
#align matrix.kronecker_map_bilinear_mul_mul Matrix.kroneckerMapBilinear_mul_mul
theorem trace_kroneckerMapBilinear [CommSemiring R] [Fintype m] [Fintype n] [AddCommMonoid α]
[AddCommMonoid β] [AddCommMonoid γ] [Module R α] [Module R β] [Module R γ]
(f : α →ₗ[R] β →ₗ[R] γ) (A : Matrix m m α) (B : Matrix n n β) :
trace (kroneckerMapBilinear f A B) = f (trace A) (trace B) := by
simp_rw [Matrix.trace, Matrix.diag, kroneckerMapBilinear_apply_apply, LinearMap.map_sum₂,
map_sum, ← Finset.univ_product_univ, Finset.sum_product, kroneckerMap_apply]
#align matrix.trace_kronecker_map_bilinear Matrix.trace_kroneckerMapBilinear
| Mathlib/Data/Matrix/Kronecker.lean | 236 | 253 | theorem det_kroneckerMapBilinear [CommSemiring R] [Fintype m] [Fintype n] [DecidableEq m]
[DecidableEq n] [CommRing α] [CommRing β] [CommRing γ] [Module R α] [Module R β] [Module R γ]
(f : α →ₗ[R] β →ₗ[R] γ) (h_comm : ∀ a b a' b', f (a * b) (a' * b') = f a a' * f b b')
(A : Matrix m m α) (B : Matrix n n β) :
det (kroneckerMapBilinear f A B) =
det (A.map fun a => f a 1) ^ Fintype.card n * det (B.map fun b => f 1 b) ^ Fintype.card m :=
calc
det (kroneckerMapBilinear f A B) =
det (kroneckerMapBilinear f A 1 * kroneckerMapBilinear f 1 B) := by |
rw [← kroneckerMapBilinear_mul_mul f h_comm, Matrix.mul_one, Matrix.one_mul]
_ = det (blockDiagonal fun _ => A.map fun a => f a 1) *
det (blockDiagonal fun _ => B.map fun b => f 1 b) := by
rw [det_mul, ← diagonal_one, ← diagonal_one, kroneckerMapBilinear_apply_apply,
kroneckerMap_diagonal_right _ fun _ => _, kroneckerMapBilinear_apply_apply,
kroneckerMap_diagonal_left _ fun _ => _, det_reindex_self]
· intro; exact LinearMap.map_zero₂ _ _
· intro; exact map_zero _
_ = _ := by simp_rw [det_blockDiagonal, Finset.prod_const, Finset.card_univ]
|
import Mathlib.GroupTheory.Submonoid.Inverses
import Mathlib.RingTheory.FiniteType
import Mathlib.RingTheory.Localization.Basic
#align_import ring_theory.localization.inv_submonoid from "leanprover-community/mathlib"@"6e7ca692c98bbf8a64868f61a67fb9c33b10770d"
variable {R : Type*} [CommRing R] (M : Submonoid R) (S : Type*) [CommRing S]
variable [Algebra R S] {P : Type*} [CommRing P]
open Function
namespace IsLocalization
section InvSubmonoid
def invSubmonoid : Submonoid S :=
(M.map (algebraMap R S)).leftInv
#align is_localization.inv_submonoid IsLocalization.invSubmonoid
variable [IsLocalization M S]
theorem submonoid_map_le_is_unit : M.map (algebraMap R S) ≤ IsUnit.submonoid S := by
rintro _ ⟨a, ha, rfl⟩
exact IsLocalization.map_units S ⟨_, ha⟩
#align is_localization.submonoid_map_le_is_unit IsLocalization.submonoid_map_le_is_unit
noncomputable abbrev equivInvSubmonoid : M.map (algebraMap R S) ≃* invSubmonoid M S :=
((M.map (algebraMap R S)).leftInvEquiv (submonoid_map_le_is_unit M S)).symm
#align is_localization.equiv_inv_submonoid IsLocalization.equivInvSubmonoid
noncomputable def toInvSubmonoid : M →* invSubmonoid M S :=
(equivInvSubmonoid M S).toMonoidHom.comp ((algebraMap R S : R →* S).submonoidMap M)
#align is_localization.to_inv_submonoid IsLocalization.toInvSubmonoid
theorem toInvSubmonoid_surjective : Function.Surjective (toInvSubmonoid M S) :=
Function.Surjective.comp (β := M.map (algebraMap R S))
(Equiv.surjective (equivInvSubmonoid _ _).toEquiv) (MonoidHom.submonoidMap_surjective _ _)
#align is_localization.to_inv_submonoid_surjective IsLocalization.toInvSubmonoid_surjective
@[simp]
theorem toInvSubmonoid_mul (m : M) : (toInvSubmonoid M S m : S) * algebraMap R S m = 1 :=
Submonoid.leftInvEquiv_symm_mul _ (submonoid_map_le_is_unit _ _) _
#align is_localization.to_inv_submonoid_mul IsLocalization.toInvSubmonoid_mul
@[simp]
theorem mul_toInvSubmonoid (m : M) : algebraMap R S m * (toInvSubmonoid M S m : S) = 1 :=
Submonoid.mul_leftInvEquiv_symm _ (submonoid_map_le_is_unit _ _) ⟨_, _⟩
#align is_localization.mul_to_inv_submonoid IsLocalization.mul_toInvSubmonoid
@[simp]
theorem smul_toInvSubmonoid (m : M) : m • (toInvSubmonoid M S m : S) = 1 := by
convert mul_toInvSubmonoid M S m
ext
rw [← Algebra.smul_def]
rfl
#align is_localization.smul_to_inv_submonoid IsLocalization.smul_toInvSubmonoid
variable {S}
-- Porting note: `surj'` was taken, so use `surj''` instead
theorem surj'' (z : S) : ∃ (r : R) (m : M), z = r • (toInvSubmonoid M S m : S) := by
rcases IsLocalization.surj M z with ⟨⟨r, m⟩, e : z * _ = algebraMap R S r⟩
refine ⟨r, m, ?_⟩
rw [Algebra.smul_def, ← e, mul_assoc]
simp
#align is_localization.surj' IsLocalization.surj''
theorem toInvSubmonoid_eq_mk' (x : M) : (toInvSubmonoid M S x : S) = mk' S 1 x := by
rw [← (IsLocalization.map_units S x).mul_left_inj]
simp
#align is_localization.to_inv_submonoid_eq_mk' IsLocalization.toInvSubmonoid_eq_mk'
theorem mem_invSubmonoid_iff_exists_mk' (x : S) :
x ∈ invSubmonoid M S ↔ ∃ m : M, mk' S 1 m = x := by
simp_rw [← toInvSubmonoid_eq_mk']
exact ⟨fun h => ⟨_, congr_arg Subtype.val (toInvSubmonoid_surjective M S ⟨x, h⟩).choose_spec⟩,
fun h => h.choose_spec ▸ (toInvSubmonoid M S h.choose).prop⟩
#align is_localization.mem_inv_submonoid_iff_exists_mk' IsLocalization.mem_invSubmonoid_iff_exists_mk'
variable (S)
theorem span_invSubmonoid : Submodule.span R (invSubmonoid M S : Set S) = ⊤ := by
rw [eq_top_iff]
rintro x -
rcases IsLocalization.surj'' M x with ⟨r, m, rfl⟩
exact Submodule.smul_mem _ _ (Submodule.subset_span (toInvSubmonoid M S m).prop)
#align is_localization.span_inv_submonoid IsLocalization.span_invSubmonoid
| Mathlib/RingTheory/Localization/InvSubmonoid.lean | 115 | 124 | theorem finiteType_of_monoid_fg [Monoid.FG M] : Algebra.FiniteType R S := by |
have := Monoid.fg_of_surjective _ (toInvSubmonoid_surjective M S)
rw [Monoid.fg_iff_submonoid_fg] at this
rcases this with ⟨s, hs⟩
refine ⟨⟨s, ?_⟩⟩
rw [eq_top_iff]
rintro x -
change x ∈ (Subalgebra.toSubmodule (Algebra.adjoin R _ : Subalgebra R S) : Set S)
rw [Algebra.adjoin_eq_span, hs, span_invSubmonoid]
trivial
|
import Mathlib.FieldTheory.Finite.Polynomial
import Mathlib.NumberTheory.Basic
import Mathlib.RingTheory.WittVector.WittPolynomial
#align_import ring_theory.witt_vector.structure_polynomial from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a"
open MvPolynomial Set
open Finset (range)
open Finsupp (single)
-- This lemma reduces a bundled morphism to a "mere" function,
-- and consequently the simplifier cannot use a lot of powerful simp-lemmas.
-- We disable this locally, and probably it should be disabled globally in mathlib.
attribute [-simp] coe_eval₂Hom
variable {p : ℕ} {R : Type*} {idx : Type*} [CommRing R]
open scoped Witt
section PPrime
variable (p) [hp : Fact p.Prime]
-- Notation with ring of coefficients explicit
set_option quotPrecheck false in
@[inherit_doc]
scoped[Witt] notation "W_" => wittPolynomial p
-- Notation with ring of coefficients implicit
set_option quotPrecheck false in
@[inherit_doc]
scoped[Witt] notation "W" => wittPolynomial p _
noncomputable def wittStructureRat (Φ : MvPolynomial idx ℚ) (n : ℕ) : MvPolynomial (idx × ℕ) ℚ :=
bind₁ (fun k => bind₁ (fun i => rename (Prod.mk i) (W_ ℚ k)) Φ) (xInTermsOfW p ℚ n)
#align witt_structure_rat wittStructureRat
theorem wittStructureRat_prop (Φ : MvPolynomial idx ℚ) (n : ℕ) :
bind₁ (wittStructureRat p Φ) (W_ ℚ n) = bind₁ (fun i => rename (Prod.mk i) (W_ ℚ n)) Φ :=
calc
bind₁ (wittStructureRat p Φ) (W_ ℚ n) =
bind₁ (fun k => bind₁ (fun i => (rename (Prod.mk i)) (W_ ℚ k)) Φ)
(bind₁ (xInTermsOfW p ℚ) (W_ ℚ n)) := by
rw [bind₁_bind₁]; exact eval₂Hom_congr (RingHom.ext_rat _ _) rfl rfl
_ = bind₁ (fun i => rename (Prod.mk i) (W_ ℚ n)) Φ := by
rw [bind₁_xInTermsOfW_wittPolynomial p _ n, bind₁_X_right]
#align witt_structure_rat_prop wittStructureRat_prop
| Mathlib/RingTheory/WittVector/StructurePolynomial.lean | 151 | 161 | theorem wittStructureRat_existsUnique (Φ : MvPolynomial idx ℚ) :
∃! φ : ℕ → MvPolynomial (idx × ℕ) ℚ,
∀ n : ℕ, bind₁ φ (W_ ℚ n) = bind₁ (fun i => rename (Prod.mk i) (W_ ℚ n)) Φ := by |
refine ⟨wittStructureRat p Φ, ?_, ?_⟩
· intro n; apply wittStructureRat_prop
· intro φ H
funext n
rw [show φ n = bind₁ φ (bind₁ (W_ ℚ) (xInTermsOfW p ℚ n)) by
rw [bind₁_wittPolynomial_xInTermsOfW p, bind₁_X_right]]
rw [bind₁_bind₁]
exact eval₂Hom_congr (RingHom.ext_rat _ _) (funext H) rfl
|
import Mathlib.Topology.Order.LeftRight
import Mathlib.Topology.Order.Monotone
#align_import topology.algebra.order.left_right_lim from "leanprover-community/mathlib"@"0a0ec35061ed9960bf0e7ffb0335f44447b58977"
open Set Filter
open Topology
section
variable {α β : Type*} [LinearOrder α] [TopologicalSpace β]
noncomputable def Function.leftLim (f : α → β) (a : α) : β := by
classical
haveI : Nonempty β := ⟨f a⟩
letI : TopologicalSpace α := Preorder.topology α
exact if 𝓝[<] a = ⊥ ∨ ¬∃ y, Tendsto f (𝓝[<] a) (𝓝 y) then f a else limUnder (𝓝[<] a) f
#align function.left_lim Function.leftLim
noncomputable def Function.rightLim (f : α → β) (a : α) : β :=
@Function.leftLim αᵒᵈ β _ _ f a
#align function.right_lim Function.rightLim
open Function
theorem leftLim_eq_of_tendsto [hα : TopologicalSpace α] [h'α : OrderTopology α] [T2Space β]
{f : α → β} {a : α} {y : β} (h : 𝓝[<] a ≠ ⊥) (h' : Tendsto f (𝓝[<] a) (𝓝 y)) :
leftLim f a = y := by
have h'' : ∃ y, Tendsto f (𝓝[<] a) (𝓝 y) := ⟨y, h'⟩
rw [h'α.topology_eq_generate_intervals] at h h' h''
simp only [leftLim, h, h'', not_true, or_self_iff, if_false]
haveI := neBot_iff.2 h
exact lim_eq h'
#align left_lim_eq_of_tendsto leftLim_eq_of_tendsto
theorem leftLim_eq_of_eq_bot [hα : TopologicalSpace α] [h'α : OrderTopology α] (f : α → β) {a : α}
(h : 𝓝[<] a = ⊥) : leftLim f a = f a := by
rw [h'α.topology_eq_generate_intervals] at h
simp [leftLim, ite_eq_left_iff, h]
#align left_lim_eq_of_eq_bot leftLim_eq_of_eq_bot
theorem rightLim_eq_of_tendsto [TopologicalSpace α] [OrderTopology α] [T2Space β]
{f : α → β} {a : α} {y : β} (h : 𝓝[>] a ≠ ⊥) (h' : Tendsto f (𝓝[>] a) (𝓝 y)) :
Function.rightLim f a = y :=
@leftLim_eq_of_tendsto αᵒᵈ _ _ _ _ _ _ f a y h h'
#align right_lim_eq_of_tendsto rightLim_eq_of_tendsto
theorem rightLim_eq_of_eq_bot [TopologicalSpace α] [OrderTopology α] (f : α → β) {a : α}
(h : 𝓝[>] a = ⊥) : rightLim f a = f a :=
@leftLim_eq_of_eq_bot αᵒᵈ _ _ _ _ _ f a h
end
open Function
namespace Monotone
variable {α β : Type*} [LinearOrder α] [ConditionallyCompleteLinearOrder β] [TopologicalSpace β]
[OrderTopology β] {f : α → β} (hf : Monotone f) {x y : α}
theorem leftLim_eq_sSup [TopologicalSpace α] [OrderTopology α] (h : 𝓝[<] x ≠ ⊥) :
leftLim f x = sSup (f '' Iio x) :=
leftLim_eq_of_tendsto h (hf.tendsto_nhdsWithin_Iio x)
#align monotone.left_lim_eq_Sup Monotone.leftLim_eq_sSup
theorem rightLim_eq_sInf [TopologicalSpace α] [OrderTopology α] (h : 𝓝[>] x ≠ ⊥) :
rightLim f x = sInf (f '' Ioi x) :=
rightLim_eq_of_tendsto h (hf.tendsto_nhdsWithin_Ioi x)
#align right_lim_eq_Inf Monotone.rightLim_eq_sInf
theorem leftLim_le (h : x ≤ y) : leftLim f x ≤ f y := by
letI : TopologicalSpace α := Preorder.topology α
haveI : OrderTopology α := ⟨rfl⟩
rcases eq_or_ne (𝓝[<] x) ⊥ with (h' | h')
· simpa [leftLim, h'] using hf h
haveI A : NeBot (𝓝[<] x) := neBot_iff.2 h'
rw [leftLim_eq_sSup hf h']
refine csSup_le ?_ ?_
· simp only [image_nonempty]
exact (forall_mem_nonempty_iff_neBot.2 A) _ self_mem_nhdsWithin
· simp only [mem_image, mem_Iio, forall_exists_index, and_imp, forall_apply_eq_imp_iff₂]
intro z hz
exact hf (hz.le.trans h)
#align monotone.left_lim_le Monotone.leftLim_le
| Mathlib/Topology/Order/LeftRightLim.lean | 125 | 136 | theorem le_leftLim (h : x < y) : f x ≤ leftLim f y := by |
letI : TopologicalSpace α := Preorder.topology α
haveI : OrderTopology α := ⟨rfl⟩
rcases eq_or_ne (𝓝[<] y) ⊥ with (h' | h')
· rw [leftLim_eq_of_eq_bot _ h']
exact hf h.le
rw [leftLim_eq_sSup hf h']
refine le_csSup ⟨f y, ?_⟩ (mem_image_of_mem _ h)
simp only [upperBounds, mem_image, mem_Iio, forall_exists_index, and_imp,
forall_apply_eq_imp_iff₂, mem_setOf_eq]
intro z hz
exact hf hz.le
|
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