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import Mathlib.Algebra.Polynomial.Eval #align_import data.polynomial.degree.lemmas from "leanprover-community/mathlib"@"728baa2f54e6062c5879a3e397ac6bac323e506f" noncomputable section open Polynomial open Finsupp Finset namespace Polynomial universe u v w variable {R : Type u} {S : Type v} {ι : Type w} {a b : R} {m n : ℕ} section Semiring variable [Semiring R] {p q r : R[X]} section Degree theorem natDegree_comp_le : natDegree (p.comp q) ≤ natDegree p * natDegree q := letI := Classical.decEq R if h0 : p.comp q = 0 then by rw [h0, natDegree_zero]; exact Nat.zero_le _ else WithBot.coe_le_coe.1 <| calc ↑(natDegree (p.comp q)) = degree (p.comp q) := (degree_eq_natDegree h0).symm _ = _ := congr_arg degree comp_eq_sum_left _ ≤ _ := degree_sum_le _ _ _ ≤ _ := Finset.sup_le fun n hn => calc degree (C (coeff p n) * q ^ n) ≤ degree (C (coeff p n)) + degree (q ^ n) := degree_mul_le _ _ _ ≤ natDegree (C (coeff p n)) + n • degree q := (add_le_add degree_le_natDegree (degree_pow_le _ _)) _ ≤ natDegree (C (coeff p n)) + n • ↑(natDegree q) := (add_le_add_left (nsmul_le_nsmul_right (@degree_le_natDegree _ _ q) n) _) _ = (n * natDegree q : ℕ) := by rw [natDegree_C, Nat.cast_zero, zero_add, nsmul_eq_mul]; simp _ ≤ (natDegree p * natDegree q : ℕ) := WithBot.coe_le_coe.2 <| mul_le_mul_of_nonneg_right (le_natDegree_of_ne_zero (mem_support_iff.1 hn)) (Nat.zero_le _) #align polynomial.nat_degree_comp_le Polynomial.natDegree_comp_le theorem degree_pos_of_root {p : R[X]} (hp : p ≠ 0) (h : IsRoot p a) : 0 < degree p := lt_of_not_ge fun hlt => by have := eq_C_of_degree_le_zero hlt rw [IsRoot, this, eval_C] at h simp only [h, RingHom.map_zero] at this exact hp this #align polynomial.degree_pos_of_root Polynomial.degree_pos_of_root theorem natDegree_le_iff_coeff_eq_zero : p.natDegree ≤ n ↔ ∀ N : ℕ, n < N → p.coeff N = 0 := by simp_rw [natDegree_le_iff_degree_le, degree_le_iff_coeff_zero, Nat.cast_lt] #align polynomial.nat_degree_le_iff_coeff_eq_zero Polynomial.natDegree_le_iff_coeff_eq_zero theorem natDegree_add_le_iff_left {n : ℕ} (p q : R[X]) (qn : q.natDegree ≤ n) : (p + q).natDegree ≤ n ↔ p.natDegree ≤ n := by refine ⟨fun h => ?_, fun h => natDegree_add_le_of_degree_le h qn⟩ refine natDegree_le_iff_coeff_eq_zero.mpr fun m hm => ?_ convert natDegree_le_iff_coeff_eq_zero.mp h m hm using 1 rw [coeff_add, natDegree_le_iff_coeff_eq_zero.mp qn _ hm, add_zero] #align polynomial.nat_degree_add_le_iff_left Polynomial.natDegree_add_le_iff_left theorem natDegree_add_le_iff_right {n : ℕ} (p q : R[X]) (pn : p.natDegree ≤ n) : (p + q).natDegree ≤ n ↔ q.natDegree ≤ n := by rw [add_comm] exact natDegree_add_le_iff_left _ _ pn #align polynomial.nat_degree_add_le_iff_right Polynomial.natDegree_add_le_iff_right theorem natDegree_C_mul_le (a : R) (f : R[X]) : (C a * f).natDegree ≤ f.natDegree := calc (C a * f).natDegree ≤ (C a).natDegree + f.natDegree := natDegree_mul_le _ = 0 + f.natDegree := by rw [natDegree_C a] _ = f.natDegree := zero_add _ set_option linter.uppercaseLean3 false in #align polynomial.nat_degree_C_mul_le Polynomial.natDegree_C_mul_le theorem natDegree_mul_C_le (f : R[X]) (a : R) : (f * C a).natDegree ≤ f.natDegree := calc (f * C a).natDegree ≤ f.natDegree + (C a).natDegree := natDegree_mul_le _ = f.natDegree + 0 := by rw [natDegree_C a] _ = f.natDegree := add_zero _ set_option linter.uppercaseLean3 false in #align polynomial.nat_degree_mul_C_le Polynomial.natDegree_mul_C_le theorem eq_natDegree_of_le_mem_support (pn : p.natDegree ≤ n) (ns : n ∈ p.support) : p.natDegree = n := le_antisymm pn (le_natDegree_of_mem_supp _ ns) #align polynomial.eq_nat_degree_of_le_mem_support Polynomial.eq_natDegree_of_le_mem_support theorem natDegree_C_mul_eq_of_mul_eq_one {ai : R} (au : ai * a = 1) : (C a * p).natDegree = p.natDegree := le_antisymm (natDegree_C_mul_le a p) (calc p.natDegree = (1 * p).natDegree := by nth_rw 1 [← one_mul p] _ = (C ai * (C a * p)).natDegree := by rw [← C_1, ← au, RingHom.map_mul, ← mul_assoc] _ ≤ (C a * p).natDegree := natDegree_C_mul_le ai (C a * p)) set_option linter.uppercaseLean3 false in #align polynomial.nat_degree_C_mul_eq_of_mul_eq_one Polynomial.natDegree_C_mul_eq_of_mul_eq_one
Mathlib/Algebra/Polynomial/Degree/Lemmas.lean
121
127
theorem natDegree_mul_C_eq_of_mul_eq_one {ai : R} (au : a * ai = 1) : (p * C a).natDegree = p.natDegree := le_antisymm (natDegree_mul_C_le p a) (calc p.natDegree = (p * 1).natDegree := by
nth_rw 1 [← mul_one p] _ = (p * C a * C ai).natDegree := by rw [← C_1, ← au, RingHom.map_mul, ← mul_assoc] _ ≤ (p * C a).natDegree := natDegree_mul_C_le (p * C a) ai)
false
import Mathlib.Algebra.Group.Equiv.Basic import Mathlib.Algebra.Group.Aut import Mathlib.Data.ZMod.Defs import Mathlib.Tactic.Ring #align_import algebra.quandle from "leanprover-community/mathlib"@"28aa996fc6fb4317f0083c4e6daf79878d81be33" open MulOpposite universe u v class Shelf (α : Type u) where act : α → α → α self_distrib : ∀ {x y z : α}, act x (act y z) = act (act x y) (act x z) #align shelf Shelf class UnitalShelf (α : Type u) extends Shelf α, One α := (one_act : ∀ a : α, act 1 a = a) (act_one : ∀ a : α, act a 1 = a) #align unital_shelf UnitalShelf @[ext] structure ShelfHom (S₁ : Type*) (S₂ : Type*) [Shelf S₁] [Shelf S₂] where toFun : S₁ → S₂ map_act' : ∀ {x y : S₁}, toFun (Shelf.act x y) = Shelf.act (toFun x) (toFun y) #align shelf_hom ShelfHom #align shelf_hom.ext_iff ShelfHom.ext_iff #align shelf_hom.ext ShelfHom.ext class Rack (α : Type u) extends Shelf α where invAct : α → α → α left_inv : ∀ x, Function.LeftInverse (invAct x) (act x) right_inv : ∀ x, Function.RightInverse (invAct x) (act x) #align rack Rack scoped[Quandles] infixr:65 " ◃ " => Shelf.act scoped[Quandles] infixr:65 " ◃⁻¹ " => Rack.invAct scoped[Quandles] infixr:25 " →◃ " => ShelfHom open Quandles namespace Rack variable {R : Type*} [Rack R] -- Porting note: No longer a need for `Rack.self_distrib` export Shelf (self_distrib) -- porting note, changed name to `act'` to not conflict with `Shelf.act` def act' (x : R) : R ≃ R where toFun := Shelf.act x invFun := invAct x left_inv := left_inv x right_inv := right_inv x #align rack.act Rack.act' @[simp] theorem act'_apply (x y : R) : act' x y = x ◃ y := rfl #align rack.act_apply Rack.act'_apply @[simp] theorem act'_symm_apply (x y : R) : (act' x).symm y = x ◃⁻¹ y := rfl #align rack.act_symm_apply Rack.act'_symm_apply @[simp] theorem invAct_apply (x y : R) : (act' x)⁻¹ y = x ◃⁻¹ y := rfl #align rack.inv_act_apply Rack.invAct_apply @[simp] theorem invAct_act_eq (x y : R) : x ◃⁻¹ x ◃ y = y := left_inv x y #align rack.inv_act_act_eq Rack.invAct_act_eq @[simp] theorem act_invAct_eq (x y : R) : x ◃ x ◃⁻¹ y = y := right_inv x y #align rack.act_inv_act_eq Rack.act_invAct_eq theorem left_cancel (x : R) {y y' : R} : x ◃ y = x ◃ y' ↔ y = y' := by constructor · apply (act' x).injective rintro rfl rfl #align rack.left_cancel Rack.left_cancel theorem left_cancel_inv (x : R) {y y' : R} : x ◃⁻¹ y = x ◃⁻¹ y' ↔ y = y' := by constructor · apply (act' x).symm.injective rintro rfl rfl #align rack.left_cancel_inv Rack.left_cancel_inv theorem self_distrib_inv {x y z : R} : x ◃⁻¹ y ◃⁻¹ z = (x ◃⁻¹ y) ◃⁻¹ x ◃⁻¹ z := by rw [← left_cancel (x ◃⁻¹ y), right_inv, ← left_cancel x, right_inv, self_distrib] repeat' rw [right_inv] #align rack.self_distrib_inv Rack.self_distrib_inv
Mathlib/Algebra/Quandle.lean
251
253
theorem ad_conj {R : Type*} [Rack R] (x y : R) : act' (x ◃ y) = act' x * act' y * (act' x)⁻¹ := by
rw [eq_mul_inv_iff_mul_eq]; ext z apply self_distrib.symm
false
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 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) #align cauchy_seq_finset_of_norm_bounded_eventually cauchySeq_finset_of_norm_bounded_eventually theorem cauchySeq_finset_of_norm_bounded {f : ι → E} (g : ι → ℝ) (hg : Summable g) (h : ∀ i, ‖f i‖ ≤ g i) : CauchySeq fun s : Finset ι => ∑ i ∈ s, f i := cauchySeq_finset_of_norm_bounded_eventually hg <| eventually_of_forall h #align cauchy_seq_finset_of_norm_bounded cauchySeq_finset_of_norm_bounded theorem cauchySeq_range_of_norm_bounded {f : ℕ → E} (g : ℕ → ℝ) (hg : CauchySeq fun n => ∑ i ∈ range n, g i) (hf : ∀ i, ‖f i‖ ≤ g i) : CauchySeq fun n => ∑ i ∈ range n, f i := by refine Metric.cauchySeq_iff'.2 fun ε hε => ?_ refine (Metric.cauchySeq_iff'.1 hg ε hε).imp fun N hg n hn => ?_ specialize hg n hn rw [dist_eq_norm, ← sum_Ico_eq_sub _ hn] at hg ⊢ calc ‖∑ k ∈ Ico N n, f k‖ ≤ ∑ k ∈ _, ‖f k‖ := norm_sum_le _ _ _ ≤ ∑ k ∈ _, g k := sum_le_sum fun x _ => hf x _ ≤ ‖∑ k ∈ _, g k‖ := le_abs_self _ _ < ε := hg #align cauchy_seq_range_of_norm_bounded cauchySeq_range_of_norm_bounded theorem cauchySeq_finset_of_summable_norm {f : ι → E} (hf : Summable fun a => ‖f a‖) : CauchySeq fun s : Finset ι => ∑ a ∈ s, f a := cauchySeq_finset_of_norm_bounded _ hf fun _i => le_rfl #align cauchy_seq_finset_of_summable_norm cauchySeq_finset_of_summable_norm theorem hasSum_of_subseq_of_summable {f : ι → E} (hf : Summable fun a => ‖f a‖) {s : α → Finset ι} {p : Filter α} [NeBot p] (hs : Tendsto s p atTop) {a : E} (ha : Tendsto (fun b => ∑ i ∈ s b, f i) p (𝓝 a)) : HasSum f a := tendsto_nhds_of_cauchySeq_of_subseq (cauchySeq_finset_of_summable_norm hf) hs ha #align has_sum_of_subseq_of_summable hasSum_of_subseq_of_summable theorem hasSum_iff_tendsto_nat_of_summable_norm {f : ℕ → E} {a : E} (hf : Summable fun i => ‖f i‖) : HasSum f a ↔ Tendsto (fun n : ℕ => ∑ i ∈ range n, f i) atTop (𝓝 a) := ⟨fun h => h.tendsto_sum_nat, fun h => hasSum_of_subseq_of_summable hf tendsto_finset_range h⟩ #align has_sum_iff_tendsto_nat_of_summable_norm hasSum_iff_tendsto_nat_of_summable_norm
Mathlib/Analysis/Normed/Group/InfiniteSum.lean
113
116
theorem Summable.of_norm_bounded [CompleteSpace E] {f : ι → E} (g : ι → ℝ) (hg : Summable g) (h : ∀ i, ‖f i‖ ≤ g i) : Summable f := by
rw [summable_iff_cauchySeq_finset] exact cauchySeq_finset_of_norm_bounded g hg h
false
import Mathlib.MeasureTheory.Measure.Haar.Basic import Mathlib.Analysis.NormedSpace.FiniteDimension import Mathlib.MeasureTheory.Measure.Haar.Unique open MeasureTheory Measure Set open scoped ENNReal variable {𝕜 E F : Type*} [NontriviallyNormedField 𝕜] [CompleteSpace 𝕜] [NormedAddCommGroup E] [MeasurableSpace E] [BorelSpace E] [NormedSpace 𝕜 E] [NormedAddCommGroup F] [MeasurableSpace F] [BorelSpace F] [NormedSpace 𝕜 F] {L : E →ₗ[𝕜] F} {μ : Measure E} {ν : Measure F} [IsAddHaarMeasure μ] [IsAddHaarMeasure ν] variable [LocallyCompactSpace E] variable (L μ ν) theorem LinearMap.exists_map_addHaar_eq_smul_addHaar' (h : Function.Surjective L) : ∃ (c : ℝ≥0∞), 0 < c ∧ c < ∞ ∧ μ.map L = (c * addHaar (univ : Set (LinearMap.ker L))) • ν := by have : ProperSpace E := .of_locallyCompactSpace 𝕜 have : FiniteDimensional 𝕜 E := .of_locallyCompactSpace 𝕜 have : ProperSpace F := by rcases subsingleton_or_nontrivial E with hE|hE · have : Subsingleton F := Function.Surjective.subsingleton h infer_instance · have : ProperSpace 𝕜 := .of_locallyCompact_module 𝕜 E have : FiniteDimensional 𝕜 F := Module.Finite.of_surjective L h exact FiniteDimensional.proper 𝕜 F let S : Submodule 𝕜 E := LinearMap.ker L obtain ⟨T, hT⟩ : ∃ T : Submodule 𝕜 E, IsCompl S T := Submodule.exists_isCompl S let M : (S × T) ≃ₗ[𝕜] E := Submodule.prodEquivOfIsCompl S T hT have M_cont : Continuous M.symm := LinearMap.continuous_of_finiteDimensional _ let P : S × T →ₗ[𝕜] T := LinearMap.snd 𝕜 S T have P_cont : Continuous P := LinearMap.continuous_of_finiteDimensional _ have I : Function.Bijective (LinearMap.domRestrict L T) := ⟨LinearMap.injective_domRestrict_iff.2 (IsCompl.inf_eq_bot hT.symm), (LinearMap.surjective_domRestrict_iff h).2 hT.symm.sup_eq_top⟩ let L' : T ≃ₗ[𝕜] F := LinearEquiv.ofBijective (LinearMap.domRestrict L T) I have L'_cont : Continuous L' := LinearMap.continuous_of_finiteDimensional _ have A : L = (L' : T →ₗ[𝕜] F).comp (P.comp (M.symm : E →ₗ[𝕜] (S × T))) := by ext x obtain ⟨y, z, hyz⟩ : ∃ (y : S) (z : T), M.symm x = (y, z) := ⟨_, _, rfl⟩ have : x = M (y, z) := by rw [← hyz]; simp only [LinearEquiv.apply_symm_apply] simp [L', P, M, this] have I : μ.map L = ((μ.map M.symm).map P).map L' := by rw [Measure.map_map, Measure.map_map, A] · rfl · exact L'_cont.measurable.comp P_cont.measurable · exact M_cont.measurable · exact L'_cont.measurable · exact P_cont.measurable let μS : Measure S := addHaar let μT : Measure T := addHaar obtain ⟨c₀, c₀_pos, c₀_fin, h₀⟩ : ∃ c₀ : ℝ≥0∞, c₀ ≠ 0 ∧ c₀ ≠ ∞ ∧ μ.map M.symm = c₀ • μS.prod μT := by have : IsAddHaarMeasure (μ.map M.symm) := M.toContinuousLinearEquiv.symm.isAddHaarMeasure_map μ refine ⟨addHaarScalarFactor (μ.map M.symm) (μS.prod μT), ?_, ENNReal.coe_ne_top, isAddLeftInvariant_eq_smul _ _⟩ simpa only [ne_eq, ENNReal.coe_eq_zero] using (addHaarScalarFactor_pos_of_isAddHaarMeasure (μ.map M.symm) (μS.prod μT)).ne' have J : (μS.prod μT).map P = (μS univ) • μT := map_snd_prod obtain ⟨c₁, c₁_pos, c₁_fin, h₁⟩ : ∃ c₁ : ℝ≥0∞, c₁ ≠ 0 ∧ c₁ ≠ ∞ ∧ μT.map L' = c₁ • ν := by have : IsAddHaarMeasure (μT.map L') := L'.toContinuousLinearEquiv.isAddHaarMeasure_map μT refine ⟨addHaarScalarFactor (μT.map L') ν, ?_, ENNReal.coe_ne_top, isAddLeftInvariant_eq_smul _ _⟩ simpa only [ne_eq, ENNReal.coe_eq_zero] using (addHaarScalarFactor_pos_of_isAddHaarMeasure (μT.map L') ν).ne' refine ⟨c₀ * c₁, by simp [pos_iff_ne_zero, c₀_pos, c₁_pos], ENNReal.mul_lt_top c₀_fin c₁_fin, ?_⟩ simp only [I, h₀, Measure.map_smul, J, smul_smul, h₁] rw [mul_assoc, mul_comm _ c₁, ← mul_assoc]
Mathlib/MeasureTheory/Measure/Haar/Disintegration.lean
106
109
theorem LinearMap.exists_map_addHaar_eq_smul_addHaar (h : Function.Surjective L) : ∃ (c : ℝ≥0∞), 0 < c ∧ μ.map L = c • ν := by
rcases L.exists_map_addHaar_eq_smul_addHaar' μ ν h with ⟨c, c_pos, -, hc⟩ exact ⟨_, by simp [c_pos, NeZero.ne addHaar], hc⟩
false
import Mathlib.Algebra.Polynomial.AlgebraMap import Mathlib.Algebra.Polynomial.BigOperators import Mathlib.Algebra.Polynomial.Degree.Lemmas import Mathlib.Algebra.Polynomial.Div #align_import data.polynomial.ring_division from "leanprover-community/mathlib"@"8efcf8022aac8e01df8d302dcebdbc25d6a886c8" noncomputable section open Polynomial open Finset namespace Polynomial universe u v w z variable {R : Type u} {S : Type v} {T : Type w} {a b : R} {n : ℕ} section CommRing variable [CommRing R] theorem le_rootMultiplicity_iff {p : R[X]} (p0 : p ≠ 0) {a : R} {n : ℕ} : n ≤ rootMultiplicity a p ↔ (X - C a) ^ n ∣ p := by classical rw [rootMultiplicity_eq_nat_find_of_nonzero p0, @Nat.le_find_iff _ (_)] simp_rw [Classical.not_not] refine ⟨fun h => ?_, fun h m hm => (pow_dvd_pow _ hm).trans h⟩ cases' n with n; · rw [pow_zero] apply one_dvd; · exact h n n.lt_succ_self #align polynomial.le_root_multiplicity_iff Polynomial.le_rootMultiplicity_iff theorem rootMultiplicity_le_iff {p : R[X]} (p0 : p ≠ 0) (a : R) (n : ℕ) : rootMultiplicity a p ≤ n ↔ ¬(X - C a) ^ (n + 1) ∣ p := by rw [← (le_rootMultiplicity_iff p0).not, not_le, Nat.lt_add_one_iff] #align polynomial.root_multiplicity_le_iff Polynomial.rootMultiplicity_le_iff
Mathlib/Algebra/Polynomial/RingDivision.lean
444
445
theorem pow_rootMultiplicity_not_dvd {p : R[X]} (p0 : p ≠ 0) (a : R) : ¬(X - C a) ^ (rootMultiplicity a p + 1) ∣ p := by
rw [← rootMultiplicity_le_iff p0]
false
import Mathlib.RingTheory.FractionalIdeal.Basic import Mathlib.RingTheory.Ideal.Norm namespace FractionalIdeal open scoped Pointwise nonZeroDivisors variable {R : Type*} [CommRing R] [IsDedekindDomain R] [Module.Free ℤ R] [Module.Finite ℤ R] variable {K : Type*} [CommRing K] [Algebra R K] [IsFractionRing R K] theorem absNorm_div_norm_eq_absNorm_div_norm {I : FractionalIdeal R⁰ K} (a : R⁰) (I₀ : Ideal R) (h : a • (I : Submodule R K) = Submodule.map (Algebra.linearMap R K) I₀) : (Ideal.absNorm I.num : ℚ) / |Algebra.norm ℤ (I.den:R)| = (Ideal.absNorm I₀ : ℚ) / |Algebra.norm ℤ (a:R)| := by rw [div_eq_div_iff] · replace h := congr_arg (I.den • ·) h have h' := congr_arg (a • ·) (den_mul_self_eq_num I) dsimp only at h h' rw [smul_comm] at h rw [h, Submonoid.smul_def, Submonoid.smul_def, ← Submodule.ideal_span_singleton_smul, ← Submodule.ideal_span_singleton_smul, ← Submodule.map_smul'', ← Submodule.map_smul'', (LinearMap.map_injective ?_).eq_iff, smul_eq_mul, smul_eq_mul] at h' · simp_rw [← Int.cast_natAbs, ← Nat.cast_mul, ← Ideal.absNorm_span_singleton] rw [← _root_.map_mul, ← _root_.map_mul, mul_comm, ← h', mul_comm] · exact LinearMap.ker_eq_bot.mpr (IsFractionRing.injective R K) all_goals simpa [Algebra.norm_eq_zero_iff] using nonZeroDivisors.coe_ne_zero _ noncomputable def absNorm : FractionalIdeal R⁰ K →*₀ ℚ where toFun I := (Ideal.absNorm I.num : ℚ) / |Algebra.norm ℤ (I.den : R)| map_zero' := by dsimp only rw [num_zero_eq, Submodule.zero_eq_bot, Ideal.absNorm_bot, Nat.cast_zero, zero_div] exact IsFractionRing.injective R K map_one' := by dsimp only rw [absNorm_div_norm_eq_absNorm_div_norm 1 ⊤ (by simp [Submodule.one_eq_range]), Ideal.absNorm_top, Nat.cast_one, OneMemClass.coe_one, _root_.map_one, abs_one, Int.cast_one, one_div_one] map_mul' I J := by dsimp only rw [absNorm_div_norm_eq_absNorm_div_norm (I.den * J.den) (I.num * J.num) (by have : Algebra.linearMap R K = (IsScalarTower.toAlgHom R R K).toLinearMap := rfl rw [coe_mul, this, Submodule.map_mul, ← this, ← den_mul_self_eq_num, ← den_mul_self_eq_num] exact Submodule.mul_smul_mul_eq_smul_mul_smul _ _ _ _), Submonoid.coe_mul, _root_.map_mul, _root_.map_mul, Nat.cast_mul, div_mul_div_comm, Int.cast_abs, Int.cast_abs, Int.cast_abs, ← abs_mul, Int.cast_mul] theorem absNorm_eq (I : FractionalIdeal R⁰ K) : absNorm I = (Ideal.absNorm I.num : ℚ) / |Algebra.norm ℤ (I.den : R)| := rfl theorem absNorm_eq' {I : FractionalIdeal R⁰ K} (a : R⁰) (I₀ : Ideal R) (h : a • (I : Submodule R K) = Submodule.map (Algebra.linearMap R K) I₀) : absNorm I = (Ideal.absNorm I₀ : ℚ) / |Algebra.norm ℤ (a:R)| := by rw [absNorm, ← absNorm_div_norm_eq_absNorm_div_norm a I₀ h, MonoidWithZeroHom.coe_mk, ZeroHom.coe_mk]
Mathlib/RingTheory/FractionalIdeal/Norm.lean
84
84
theorem absNorm_nonneg (I : FractionalIdeal R⁰ K) : 0 ≤ absNorm I := by
dsimp [absNorm]; positivity
false
import Mathlib.Algebra.Group.Fin import Mathlib.LinearAlgebra.Matrix.Symmetric #align_import linear_algebra.matrix.circulant from "leanprover-community/mathlib"@"3e068ece210655b7b9a9477c3aff38a492400aa1" variable {α β m n R : Type*} namespace Matrix open Function open Matrix def circulant [Sub n] (v : n → α) : Matrix n n α := of fun i j => v (i - j) #align matrix.circulant Matrix.circulant -- TODO: set as an equation lemma for `circulant`, see mathlib4#3024 @[simp] theorem circulant_apply [Sub n] (v : n → α) (i j) : circulant v i j = v (i - j) := rfl #align matrix.circulant_apply Matrix.circulant_apply theorem circulant_col_zero_eq [AddGroup n] (v : n → α) (i : n) : circulant v i 0 = v i := congr_arg v (sub_zero _) #align matrix.circulant_col_zero_eq Matrix.circulant_col_zero_eq theorem circulant_injective [AddGroup n] : Injective (circulant : (n → α) → Matrix n n α) := by intro v w h ext k rw [← circulant_col_zero_eq v, ← circulant_col_zero_eq w, h] #align matrix.circulant_injective Matrix.circulant_injective theorem Fin.circulant_injective : ∀ n, Injective fun v : Fin n → α => circulant v | 0 => by simp [Injective] | n + 1 => Matrix.circulant_injective #align matrix.fin.circulant_injective Matrix.Fin.circulant_injective @[simp] theorem circulant_inj [AddGroup n] {v w : n → α} : circulant v = circulant w ↔ v = w := circulant_injective.eq_iff #align matrix.circulant_inj Matrix.circulant_inj @[simp] theorem Fin.circulant_inj {n} {v w : Fin n → α} : circulant v = circulant w ↔ v = w := (Fin.circulant_injective n).eq_iff #align matrix.fin.circulant_inj Matrix.Fin.circulant_inj theorem transpose_circulant [AddGroup n] (v : n → α) : (circulant v)ᵀ = circulant fun i => v (-i) := by ext; simp #align matrix.transpose_circulant Matrix.transpose_circulant theorem conjTranspose_circulant [Star α] [AddGroup n] (v : n → α) : (circulant v)ᴴ = circulant (star fun i => v (-i)) := by ext; simp #align matrix.conj_transpose_circulant Matrix.conjTranspose_circulant theorem Fin.transpose_circulant : ∀ {n} (v : Fin n → α), (circulant v)ᵀ = circulant fun i => v (-i) | 0 => by simp [Injective, eq_iff_true_of_subsingleton] | n + 1 => Matrix.transpose_circulant #align matrix.fin.transpose_circulant Matrix.Fin.transpose_circulant theorem Fin.conjTranspose_circulant [Star α] : ∀ {n} (v : Fin n → α), (circulant v)ᴴ = circulant (star fun i => v (-i)) | 0 => by simp [Injective, eq_iff_true_of_subsingleton] | n + 1 => Matrix.conjTranspose_circulant #align matrix.fin.conj_transpose_circulant Matrix.Fin.conjTranspose_circulant theorem map_circulant [Sub n] (v : n → α) (f : α → β) : (circulant v).map f = circulant fun i => f (v i) := ext fun _ _ => rfl #align matrix.map_circulant Matrix.map_circulant theorem circulant_neg [Neg α] [Sub n] (v : n → α) : circulant (-v) = -circulant v := ext fun _ _ => rfl #align matrix.circulant_neg Matrix.circulant_neg @[simp] theorem circulant_zero (α n) [Zero α] [Sub n] : circulant 0 = (0 : Matrix n n α) := ext fun _ _ => rfl #align matrix.circulant_zero Matrix.circulant_zero theorem circulant_add [Add α] [Sub n] (v w : n → α) : circulant (v + w) = circulant v + circulant w := ext fun _ _ => rfl #align matrix.circulant_add Matrix.circulant_add theorem circulant_sub [Sub α] [Sub n] (v w : n → α) : circulant (v - w) = circulant v - circulant w := ext fun _ _ => rfl #align matrix.circulant_sub Matrix.circulant_sub
Mathlib/LinearAlgebra/Matrix/Circulant.lean
126
132
theorem circulant_mul [Semiring α] [Fintype n] [AddGroup n] (v w : n → α) : circulant v * circulant w = circulant (circulant v *ᵥ w) := by
ext i j simp only [mul_apply, mulVec, circulant_apply, dotProduct] refine Fintype.sum_equiv (Equiv.subRight j) _ _ ?_ intro x simp only [Equiv.subRight_apply, sub_sub_sub_cancel_right]
false
import Mathlib.Topology.Bases import Mathlib.Topology.DenseEmbedding #align_import topology.stone_cech from "leanprover-community/mathlib"@"0a0ec35061ed9960bf0e7ffb0335f44447b58977" noncomputable section open Filter Set open Topology universe u v section Ultrafilter def ultrafilterBasis (α : Type u) : Set (Set (Ultrafilter α)) := range fun s : Set α => { u | s ∈ u } #align ultrafilter_basis ultrafilterBasis variable {α : Type u} instance Ultrafilter.topologicalSpace : TopologicalSpace (Ultrafilter α) := TopologicalSpace.generateFrom (ultrafilterBasis α) #align ultrafilter.topological_space Ultrafilter.topologicalSpace theorem ultrafilterBasis_is_basis : TopologicalSpace.IsTopologicalBasis (ultrafilterBasis α) := ⟨by rintro _ ⟨a, rfl⟩ _ ⟨b, rfl⟩ u ⟨ua, ub⟩ refine ⟨_, ⟨a ∩ b, rfl⟩, inter_mem ua ub, fun v hv => ⟨?_, ?_⟩⟩ <;> apply mem_of_superset hv <;> simp [inter_subset_right], eq_univ_of_univ_subset <| subset_sUnion_of_mem <| ⟨univ, eq_univ_of_forall fun u => univ_mem⟩, rfl⟩ #align ultrafilter_basis_is_basis ultrafilterBasis_is_basis theorem ultrafilter_isOpen_basic (s : Set α) : IsOpen { u : Ultrafilter α | s ∈ u } := ultrafilterBasis_is_basis.isOpen ⟨s, rfl⟩ #align ultrafilter_is_open_basic ultrafilter_isOpen_basic theorem ultrafilter_isClosed_basic (s : Set α) : IsClosed { u : Ultrafilter α | s ∈ u } := by rw [← isOpen_compl_iff] convert ultrafilter_isOpen_basic sᶜ using 1 ext u exact Ultrafilter.compl_mem_iff_not_mem.symm #align ultrafilter_is_closed_basic ultrafilter_isClosed_basic theorem ultrafilter_converges_iff {u : Ultrafilter (Ultrafilter α)} {x : Ultrafilter α} : ↑u ≤ 𝓝 x ↔ x = joinM u := by rw [eq_comm, ← Ultrafilter.coe_le_coe] change ↑u ≤ 𝓝 x ↔ ∀ s ∈ x, { v : Ultrafilter α | s ∈ v } ∈ u simp only [TopologicalSpace.nhds_generateFrom, le_iInf_iff, ultrafilterBasis, le_principal_iff, mem_setOf_eq] constructor · intro h a ha exact h _ ⟨ha, a, rfl⟩ · rintro h a ⟨xi, a, rfl⟩ exact h _ xi #align ultrafilter_converges_iff ultrafilter_converges_iff instance ultrafilter_compact : CompactSpace (Ultrafilter α) := ⟨isCompact_iff_ultrafilter_le_nhds.mpr fun f _ => ⟨joinM f, trivial, ultrafilter_converges_iff.mpr rfl⟩⟩ #align ultrafilter_compact ultrafilter_compact instance Ultrafilter.t2Space : T2Space (Ultrafilter α) := t2_iff_ultrafilter.mpr @fun x y f fx fy => have hx : x = joinM f := ultrafilter_converges_iff.mp fx have hy : y = joinM f := ultrafilter_converges_iff.mp fy hx.trans hy.symm #align ultrafilter.t2_space Ultrafilter.t2Space instance : TotallyDisconnectedSpace (Ultrafilter α) := by rw [totallyDisconnectedSpace_iff_connectedComponent_singleton] intro A simp only [Set.eq_singleton_iff_unique_mem, mem_connectedComponent, true_and_iff] intro B hB rw [← Ultrafilter.coe_le_coe] intro s hs rw [connectedComponent_eq_iInter_isClopen, Set.mem_iInter] at hB let Z := { F : Ultrafilter α | s ∈ F } have hZ : IsClopen Z := ⟨ultrafilter_isClosed_basic s, ultrafilter_isOpen_basic s⟩ exact hB ⟨Z, hZ, hs⟩ @[simp] theorem Ultrafilter.tendsto_pure_self (b : Ultrafilter α) : Tendsto pure b (𝓝 b) := by rw [Tendsto, ← coe_map, ultrafilter_converges_iff] ext s change s ∈ b ↔ {t | s ∈ t} ∈ map pure b simp_rw [mem_map, preimage_setOf_eq, mem_pure, setOf_mem_eq] theorem ultrafilter_comap_pure_nhds (b : Ultrafilter α) : comap pure (𝓝 b) ≤ b := by rw [TopologicalSpace.nhds_generateFrom] simp only [comap_iInf, comap_principal] intro s hs rw [← le_principal_iff] refine iInf_le_of_le { u | s ∈ u } ?_ refine iInf_le_of_le ⟨hs, ⟨s, rfl⟩⟩ ?_ exact principal_mono.2 fun a => id #align ultrafilter_comap_pure_nhds ultrafilter_comap_pure_nhds section Embedding
Mathlib/Topology/StoneCech.lean
122
126
theorem ultrafilter_pure_injective : Function.Injective (pure : α → Ultrafilter α) := by
intro x y h have : {x} ∈ (pure x : Ultrafilter α) := singleton_mem_pure rw [h] at this exact (mem_singleton_iff.mp (mem_pure.mp this)).symm
false
import Mathlib.Combinatorics.Hall.Finite import Mathlib.CategoryTheory.CofilteredSystem import Mathlib.Data.Rel #align_import combinatorics.hall.basic from "leanprover-community/mathlib"@"8195826f5c428fc283510bc67303dd4472d78498" open Finset CategoryTheory universe u v def hallMatchingsOn {ι : Type u} {α : Type v} (t : ι → Finset α) (ι' : Finset ι) := { f : ι' → α | Function.Injective f ∧ ∀ x, f x ∈ t x } #align hall_matchings_on hallMatchingsOn def hallMatchingsOn.restrict {ι : Type u} {α : Type v} (t : ι → Finset α) {ι' ι'' : Finset ι} (h : ι' ⊆ ι'') (f : hallMatchingsOn t ι'') : hallMatchingsOn t ι' := by refine ⟨fun i => f.val ⟨i, h i.property⟩, ?_⟩ cases' f.property with hinj hc refine ⟨?_, fun i => hc ⟨i, h i.property⟩⟩ rintro ⟨i, hi⟩ ⟨j, hj⟩ hh simpa only [Subtype.mk_eq_mk] using hinj hh #align hall_matchings_on.restrict hallMatchingsOn.restrict
Mathlib/Combinatorics/Hall/Basic.lean
77
86
theorem hallMatchingsOn.nonempty {ι : Type u} {α : Type v} [DecidableEq α] (t : ι → Finset α) (h : ∀ s : Finset ι, s.card ≤ (s.biUnion t).card) (ι' : Finset ι) : Nonempty (hallMatchingsOn t ι') := by
classical refine ⟨Classical.indefiniteDescription _ ?_⟩ apply (all_card_le_biUnion_card_iff_existsInjective' fun i : ι' => t i).mp intro s' convert h (s'.image (↑)) using 1 · simp only [card_image_of_injective s' Subtype.coe_injective] · rw [image_biUnion]
false
import Mathlib.Probability.ConditionalProbability import Mathlib.MeasureTheory.Measure.Count #align_import probability.cond_count from "leanprover-community/mathlib"@"117e93f82b5f959f8193857370109935291f0cc4" noncomputable section open ProbabilityTheory open MeasureTheory MeasurableSpace namespace ProbabilityTheory variable {Ω : Type*} [MeasurableSpace Ω] def condCount (s : Set Ω) : Measure Ω := Measure.count[|s] #align probability_theory.cond_count ProbabilityTheory.condCount @[simp] theorem condCount_empty_meas : (condCount ∅ : Measure Ω) = 0 := by simp [condCount] #align probability_theory.cond_count_empty_meas ProbabilityTheory.condCount_empty_meas theorem condCount_empty {s : Set Ω} : condCount s ∅ = 0 := by simp #align probability_theory.cond_count_empty ProbabilityTheory.condCount_empty theorem finite_of_condCount_ne_zero {s t : Set Ω} (h : condCount s t ≠ 0) : s.Finite := by by_contra hs' simp [condCount, cond, Measure.count_apply_infinite hs'] at h #align probability_theory.finite_of_cond_count_ne_zero ProbabilityTheory.finite_of_condCount_ne_zero theorem condCount_univ [Fintype Ω] {s : Set Ω} : condCount Set.univ s = Measure.count s / Fintype.card Ω := by rw [condCount, cond_apply _ MeasurableSet.univ, ← ENNReal.div_eq_inv_mul, Set.univ_inter] congr rw [← Finset.coe_univ, Measure.count_apply, Finset.univ.tsum_subtype' fun _ => (1 : ENNReal)] · simp [Finset.card_univ] · exact (@Finset.coe_univ Ω _).symm ▸ MeasurableSet.univ #align probability_theory.cond_count_univ ProbabilityTheory.condCount_univ variable [MeasurableSingletonClass Ω] theorem condCount_isProbabilityMeasure {s : Set Ω} (hs : s.Finite) (hs' : s.Nonempty) : IsProbabilityMeasure (condCount s) := { measure_univ := by rw [condCount, cond_apply _ hs.measurableSet, Set.inter_univ, ENNReal.inv_mul_cancel] · exact fun h => hs'.ne_empty <| Measure.empty_of_count_eq_zero h · exact (Measure.count_apply_lt_top.2 hs).ne } #align probability_theory.cond_count_is_probability_measure ProbabilityTheory.condCount_isProbabilityMeasure theorem condCount_singleton (ω : Ω) (t : Set Ω) [Decidable (ω ∈ t)] : condCount {ω} t = if ω ∈ t then 1 else 0 := by rw [condCount, cond_apply _ (measurableSet_singleton ω), Measure.count_singleton, inv_one, one_mul] split_ifs · rw [(by simpa : ({ω} : Set Ω) ∩ t = {ω}), Measure.count_singleton] · rw [(by simpa : ({ω} : Set Ω) ∩ t = ∅), Measure.count_empty] #align probability_theory.cond_count_singleton ProbabilityTheory.condCount_singleton variable {s t u : Set Ω} theorem condCount_inter_self (hs : s.Finite) : condCount s (s ∩ t) = condCount s t := by rw [condCount, cond_inter_self _ hs.measurableSet] #align probability_theory.cond_count_inter_self ProbabilityTheory.condCount_inter_self theorem condCount_self (hs : s.Finite) (hs' : s.Nonempty) : condCount s s = 1 := by rw [condCount, cond_apply _ hs.measurableSet, Set.inter_self, ENNReal.inv_mul_cancel] · exact fun h => hs'.ne_empty <| Measure.empty_of_count_eq_zero h · exact (Measure.count_apply_lt_top.2 hs).ne #align probability_theory.cond_count_self ProbabilityTheory.condCount_self theorem condCount_eq_one_of (hs : s.Finite) (hs' : s.Nonempty) (ht : s ⊆ t) : condCount s t = 1 := by haveI := condCount_isProbabilityMeasure hs hs' refine eq_of_le_of_not_lt prob_le_one ?_ rw [not_lt, ← condCount_self hs hs'] exact measure_mono ht #align probability_theory.cond_count_eq_one_of ProbabilityTheory.condCount_eq_one_of theorem pred_true_of_condCount_eq_one (h : condCount s t = 1) : s ⊆ t := by have hsf := finite_of_condCount_ne_zero (by rw [h]; exact one_ne_zero) rw [condCount, cond_apply _ hsf.measurableSet, mul_comm] at h replace h := ENNReal.eq_inv_of_mul_eq_one_left h rw [inv_inv, Measure.count_apply_finite _ hsf, Measure.count_apply_finite _ (hsf.inter_of_left _), Nat.cast_inj] at h suffices s ∩ t = s by exact this ▸ fun x hx => hx.2 rw [← @Set.Finite.toFinset_inj _ _ _ (hsf.inter_of_left _) hsf] exact Finset.eq_of_subset_of_card_le (Set.Finite.toFinset_mono s.inter_subset_left) h.ge #align probability_theory.pred_true_of_cond_count_eq_one ProbabilityTheory.pred_true_of_condCount_eq_one theorem condCount_eq_zero_iff (hs : s.Finite) : condCount s t = 0 ↔ s ∩ t = ∅ := by simp [condCount, cond_apply _ hs.measurableSet, Measure.count_apply_eq_top, Set.not_infinite.2 hs, Measure.count_apply_finite _ (hs.inter_of_left _)] #align probability_theory.cond_count_eq_zero_iff ProbabilityTheory.condCount_eq_zero_iff theorem condCount_of_univ (hs : s.Finite) (hs' : s.Nonempty) : condCount s Set.univ = 1 := condCount_eq_one_of hs hs' s.subset_univ #align probability_theory.cond_count_of_univ ProbabilityTheory.condCount_of_univ
Mathlib/Probability/CondCount.lean
138
148
theorem condCount_inter (hs : s.Finite) : condCount s (t ∩ u) = condCount (s ∩ t) u * condCount s t := by
by_cases hst : s ∩ t = ∅ · rw [hst, condCount_empty_meas, Measure.coe_zero, Pi.zero_apply, zero_mul, condCount_eq_zero_iff hs, ← Set.inter_assoc, hst, Set.empty_inter] rw [condCount, condCount, cond_apply _ hs.measurableSet, cond_apply _ hs.measurableSet, cond_apply _ (hs.inter_of_left _).measurableSet, mul_comm _ (Measure.count (s ∩ t)), ← mul_assoc, mul_comm _ (Measure.count (s ∩ t)), ← mul_assoc, ENNReal.mul_inv_cancel, one_mul, mul_comm, Set.inter_assoc] · rwa [← Measure.count_eq_zero_iff] at hst · exact (Measure.count_apply_lt_top.2 <| hs.inter_of_left _).ne
false
import Mathlib.Algebra.Order.Ring.Abs import Mathlib.Algebra.Order.Ring.Rat import Mathlib.Data.Rat.Lemmas import Mathlib.Data.Int.Sqrt #align_import data.rat.sqrt from "leanprover-community/mathlib"@"46a64b5b4268c594af770c44d9e502afc6a515cb" namespace Rat -- @[pp_nodot] porting note: unknown attribute def sqrt (q : ℚ) : ℚ := mkRat (Int.sqrt q.num) (Nat.sqrt q.den) #align rat.sqrt Rat.sqrt
Mathlib/Data/Rat/Sqrt.lean
30
31
theorem sqrt_eq (q : ℚ) : Rat.sqrt (q * q) = |q| := by
rw [sqrt, mul_self_num, mul_self_den, Int.sqrt_eq, Nat.sqrt_eq, abs_def, divInt_ofNat]
false
import Mathlib.Data.Set.Function import Mathlib.Analysis.BoundedVariation #align_import analysis.constant_speed from "leanprover-community/mathlib"@"f0c8bf9245297a541f468be517f1bde6195105e9" open scoped NNReal ENNReal open Set MeasureTheory Classical variable {α : Type*} [LinearOrder α] {E : Type*} [PseudoEMetricSpace E] variable (f : ℝ → E) (s : Set ℝ) (l : ℝ≥0) def HasConstantSpeedOnWith := ∀ ⦃x⦄ (_ : x ∈ s) ⦃y⦄ (_ : y ∈ s), eVariationOn f (s ∩ Icc x y) = ENNReal.ofReal (l * (y - x)) #align has_constant_speed_on_with HasConstantSpeedOnWith variable {f s l} theorem HasConstantSpeedOnWith.hasLocallyBoundedVariationOn (h : HasConstantSpeedOnWith f s l) : LocallyBoundedVariationOn f s := fun x y hx hy => by simp only [BoundedVariationOn, h hx hy, Ne, ENNReal.ofReal_ne_top, not_false_iff] #align has_constant_speed_on_with.has_locally_bounded_variation_on HasConstantSpeedOnWith.hasLocallyBoundedVariationOn
Mathlib/Analysis/ConstantSpeed.lean
64
68
theorem hasConstantSpeedOnWith_of_subsingleton (f : ℝ → E) {s : Set ℝ} (hs : s.Subsingleton) (l : ℝ≥0) : HasConstantSpeedOnWith f s l := by
rintro x hx y hy; cases hs hx hy rw [eVariationOn.subsingleton f (fun y hy z hz => hs hy.1 hz.1 : (s ∩ Icc x x).Subsingleton)] simp only [sub_self, mul_zero, ENNReal.ofReal_zero]
false
import Mathlib.Data.List.Forall2 #align_import data.list.zip from "leanprover-community/mathlib"@"134625f523e737f650a6ea7f0c82a6177e45e622" -- Make sure we don't import algebra assert_not_exists Monoid universe u open Nat namespace List variable {α : Type u} {β γ δ ε : Type*} #align list.zip_with_cons_cons List.zipWith_cons_cons #align list.zip_cons_cons List.zip_cons_cons #align list.zip_with_nil_left List.zipWith_nil_left #align list.zip_with_nil_right List.zipWith_nil_right #align list.zip_with_eq_nil_iff List.zipWith_eq_nil_iff #align list.zip_nil_left List.zip_nil_left #align list.zip_nil_right List.zip_nil_right @[simp] theorem zip_swap : ∀ (l₁ : List α) (l₂ : List β), (zip l₁ l₂).map Prod.swap = zip l₂ l₁ | [], l₂ => zip_nil_right.symm | l₁, [] => by rw [zip_nil_right]; rfl | a :: l₁, b :: l₂ => by simp only [zip_cons_cons, map_cons, zip_swap l₁ l₂, Prod.swap_prod_mk] #align list.zip_swap List.zip_swap #align list.length_zip_with List.length_zipWith #align list.length_zip List.length_zip theorem forall_zipWith {f : α → β → γ} {p : γ → Prop} : ∀ {l₁ : List α} {l₂ : List β}, length l₁ = length l₂ → (Forall p (zipWith f l₁ l₂) ↔ Forall₂ (fun x y => p (f x y)) l₁ l₂) | [], [], _ => by simp | a :: l₁, b :: l₂, h => by simp only [length_cons, succ_inj'] at h simp [forall_zipWith h] #align list.all₂_zip_with List.forall_zipWith theorem lt_length_left_of_zipWith {f : α → β → γ} {i : ℕ} {l : List α} {l' : List β} (h : i < (zipWith f l l').length) : i < l.length := by rw [length_zipWith] at h; omega #align list.lt_length_left_of_zip_with List.lt_length_left_of_zipWith theorem lt_length_right_of_zipWith {f : α → β → γ} {i : ℕ} {l : List α} {l' : List β} (h : i < (zipWith f l l').length) : i < l'.length := by rw [length_zipWith] at h; omega #align list.lt_length_right_of_zip_with List.lt_length_right_of_zipWith theorem lt_length_left_of_zip {i : ℕ} {l : List α} {l' : List β} (h : i < (zip l l').length) : i < l.length := lt_length_left_of_zipWith h #align list.lt_length_left_of_zip List.lt_length_left_of_zip theorem lt_length_right_of_zip {i : ℕ} {l : List α} {l' : List β} (h : i < (zip l l').length) : i < l'.length := lt_length_right_of_zipWith h #align list.lt_length_right_of_zip List.lt_length_right_of_zip #align list.zip_append List.zip_append #align list.zip_map List.zip_map #align list.zip_map_left List.zip_map_left #align list.zip_map_right List.zip_map_right #align list.zip_with_map List.zipWith_map #align list.zip_with_map_left List.zipWith_map_left #align list.zip_with_map_right List.zipWith_map_right #align list.zip_map' List.zip_map' #align list.map_zip_with List.map_zipWith theorem mem_zip {a b} : ∀ {l₁ : List α} {l₂ : List β}, (a, b) ∈ zip l₁ l₂ → a ∈ l₁ ∧ b ∈ l₂ | _ :: l₁, _ :: l₂, h => by cases' h with _ _ _ h · simp · have := mem_zip h exact ⟨Mem.tail _ this.1, Mem.tail _ this.2⟩ #align list.mem_zip List.mem_zip #align list.map_fst_zip List.map_fst_zip #align list.map_snd_zip List.map_snd_zip #align list.unzip_nil List.unzip_nil #align list.unzip_cons List.unzip_cons theorem unzip_eq_map : ∀ l : List (α × β), unzip l = (l.map Prod.fst, l.map Prod.snd) | [] => rfl | (a, b) :: l => by simp only [unzip_cons, map_cons, unzip_eq_map l] #align list.unzip_eq_map List.unzip_eq_map theorem unzip_left (l : List (α × β)) : (unzip l).1 = l.map Prod.fst := by simp only [unzip_eq_map] #align list.unzip_left List.unzip_left theorem unzip_right (l : List (α × β)) : (unzip l).2 = l.map Prod.snd := by simp only [unzip_eq_map] #align list.unzip_right List.unzip_right theorem unzip_swap (l : List (α × β)) : unzip (l.map Prod.swap) = (unzip l).swap := by simp only [unzip_eq_map, map_map] rfl #align list.unzip_swap List.unzip_swap theorem zip_unzip : ∀ l : List (α × β), zip (unzip l).1 (unzip l).2 = l | [] => rfl | (a, b) :: l => by simp only [unzip_cons, zip_cons_cons, zip_unzip l] #align list.zip_unzip List.zip_unzip theorem unzip_zip_left : ∀ {l₁ : List α} {l₂ : List β}, length l₁ ≤ length l₂ → (unzip (zip l₁ l₂)).1 = l₁ | [], l₂, _ => rfl | l₁, [], h => by rw [eq_nil_of_length_eq_zero (Nat.eq_zero_of_le_zero h)]; rfl | a :: l₁, b :: l₂, h => by simp only [zip_cons_cons, unzip_cons, unzip_zip_left (le_of_succ_le_succ h)] #align list.unzip_zip_left List.unzip_zip_left
Mathlib/Data/List/Zip.lean
133
134
theorem unzip_zip_right {l₁ : List α} {l₂ : List β} (h : length l₂ ≤ length l₁) : (unzip (zip l₁ l₂)).2 = l₂ := by
rw [← zip_swap, unzip_swap]; exact unzip_zip_left h
false
import Mathlib.Algebra.GCDMonoid.Multiset import Mathlib.Combinatorics.Enumerative.Partition import Mathlib.Data.List.Rotate import Mathlib.GroupTheory.Perm.Cycle.Factors import Mathlib.GroupTheory.Perm.Closure import Mathlib.Algebra.GCDMonoid.Nat import Mathlib.Tactic.NormNum.GCD #align_import group_theory.perm.cycle.type from "leanprover-community/mathlib"@"47adfab39a11a072db552f47594bf8ed2cf8a722" namespace Equiv.Perm open Equiv List Multiset variable {α : Type*} [Fintype α] section CycleType variable [DecidableEq α] def cycleType (σ : Perm α) : Multiset ℕ := σ.cycleFactorsFinset.1.map (Finset.card ∘ support) #align equiv.perm.cycle_type Equiv.Perm.cycleType theorem cycleType_def (σ : Perm α) : σ.cycleType = σ.cycleFactorsFinset.1.map (Finset.card ∘ support) := rfl #align equiv.perm.cycle_type_def Equiv.Perm.cycleType_def theorem cycleType_eq' {σ : Perm α} (s : Finset (Perm α)) (h1 : ∀ f : Perm α, f ∈ s → f.IsCycle) (h2 : (s : Set (Perm α)).Pairwise Disjoint) (h0 : s.noncommProd id (h2.imp fun _ _ => Disjoint.commute) = σ) : σ.cycleType = s.1.map (Finset.card ∘ support) := by rw [cycleType_def] congr rw [cycleFactorsFinset_eq_finset] exact ⟨h1, h2, h0⟩ #align equiv.perm.cycle_type_eq' Equiv.Perm.cycleType_eq' theorem cycleType_eq {σ : Perm α} (l : List (Perm α)) (h0 : l.prod = σ) (h1 : ∀ σ : Perm α, σ ∈ l → σ.IsCycle) (h2 : l.Pairwise Disjoint) : σ.cycleType = l.map (Finset.card ∘ support) := by have hl : l.Nodup := nodup_of_pairwise_disjoint_cycles h1 h2 rw [cycleType_eq' l.toFinset] · simp [List.dedup_eq_self.mpr hl, (· ∘ ·)] · simpa using h1 · simpa [hl] using h2 · simp [hl, h0] #align equiv.perm.cycle_type_eq Equiv.Perm.cycleType_eq @[simp] -- Porting note: new attr
Mathlib/GroupTheory/Perm/Cycle/Type.lean
79
80
theorem cycleType_eq_zero {σ : Perm α} : σ.cycleType = 0 ↔ σ = 1 := by
simp [cycleType_def, cycleFactorsFinset_eq_empty_iff]
false
import Mathlib.Combinatorics.SimpleGraph.Subgraph import Mathlib.Data.List.Rotate #align_import combinatorics.simple_graph.connectivity from "leanprover-community/mathlib"@"b99e2d58a5e6861833fa8de11e51a81144258db4" open Function universe u v w namespace SimpleGraph variable {V : Type u} {V' : Type v} {V'' : Type w} variable (G : SimpleGraph V) (G' : SimpleGraph V') (G'' : SimpleGraph V'') inductive Walk : V → V → Type u | nil {u : V} : Walk u u | cons {u v w : V} (h : G.Adj u v) (p : Walk v w) : Walk u w deriving DecidableEq #align simple_graph.walk SimpleGraph.Walk attribute [refl] Walk.nil @[simps] instance Walk.instInhabited (v : V) : Inhabited (G.Walk v v) := ⟨Walk.nil⟩ #align simple_graph.walk.inhabited SimpleGraph.Walk.instInhabited @[match_pattern, reducible] def Adj.toWalk {G : SimpleGraph V} {u v : V} (h : G.Adj u v) : G.Walk u v := Walk.cons h Walk.nil #align simple_graph.adj.to_walk SimpleGraph.Adj.toWalk namespace Walk variable {G} @[match_pattern] abbrev nil' (u : V) : G.Walk u u := Walk.nil #align simple_graph.walk.nil' SimpleGraph.Walk.nil' @[match_pattern] abbrev cons' (u v w : V) (h : G.Adj u v) (p : G.Walk v w) : G.Walk u w := Walk.cons h p #align simple_graph.walk.cons' SimpleGraph.Walk.cons' protected def copy {u v u' v'} (p : G.Walk u v) (hu : u = u') (hv : v = v') : G.Walk u' v' := hu ▸ hv ▸ p #align simple_graph.walk.copy SimpleGraph.Walk.copy @[simp] theorem copy_rfl_rfl {u v} (p : G.Walk u v) : p.copy rfl rfl = p := rfl #align simple_graph.walk.copy_rfl_rfl SimpleGraph.Walk.copy_rfl_rfl @[simp] theorem copy_copy {u v u' v' u'' v''} (p : G.Walk u v) (hu : u = u') (hv : v = v') (hu' : u' = u'') (hv' : v' = v'') : (p.copy hu hv).copy hu' hv' = p.copy (hu.trans hu') (hv.trans hv') := by subst_vars rfl #align simple_graph.walk.copy_copy SimpleGraph.Walk.copy_copy @[simp] theorem copy_nil {u u'} (hu : u = u') : (Walk.nil : G.Walk u u).copy hu hu = Walk.nil := by subst_vars rfl #align simple_graph.walk.copy_nil SimpleGraph.Walk.copy_nil
Mathlib/Combinatorics/SimpleGraph/Connectivity.lean
146
149
theorem copy_cons {u v w u' w'} (h : G.Adj u v) (p : G.Walk v w) (hu : u = u') (hw : w = w') : (Walk.cons h p).copy hu hw = Walk.cons (hu ▸ h) (p.copy rfl hw) := by
subst_vars rfl
false
import Mathlib.Algebra.Order.Group.PiLex import Mathlib.Data.DFinsupp.Order import Mathlib.Data.DFinsupp.NeLocus import Mathlib.Order.WellFoundedSet #align_import data.dfinsupp.lex from "leanprover-community/mathlib"@"dde670c9a3f503647fd5bfdf1037bad526d3397a" variable {ι : Type*} {α : ι → Type*} namespace DFinsupp section Zero variable [∀ i, Zero (α i)] protected def Lex (r : ι → ι → Prop) (s : ∀ i, α i → α i → Prop) (x y : Π₀ i, α i) : Prop := Pi.Lex r (s _) x y #align dfinsupp.lex DFinsupp.Lex -- Porting note: Added `_root_` to match more closely with Lean 3. Also updated `s`'s type. theorem _root_.Pi.lex_eq_dfinsupp_lex {r : ι → ι → Prop} {s : ∀ i, α i → α i → Prop} (a b : Π₀ i, α i) : Pi.Lex r (s _) (a : ∀ i, α i) b = DFinsupp.Lex r s a b := rfl #align pi.lex_eq_dfinsupp_lex Pi.lex_eq_dfinsupp_lex -- Porting note: Updated `s`'s type. theorem lex_def {r : ι → ι → Prop} {s : ∀ i, α i → α i → Prop} {a b : Π₀ i, α i} : DFinsupp.Lex r s a b ↔ ∃ j, (∀ d, r d j → a d = b d) ∧ s j (a j) (b j) := Iff.rfl #align dfinsupp.lex_def DFinsupp.lex_def instance [LT ι] [∀ i, LT (α i)] : LT (Lex (Π₀ i, α i)) := ⟨fun f g ↦ DFinsupp.Lex (· < ·) (fun _ ↦ (· < ·)) (ofLex f) (ofLex g)⟩
Mathlib/Data/DFinsupp/Lex.lean
51
58
theorem lex_lt_of_lt_of_preorder [∀ i, Preorder (α i)] (r) [IsStrictOrder ι r] {x y : Π₀ i, α i} (hlt : x < y) : ∃ i, (∀ j, r j i → x j ≤ y j ∧ y j ≤ x j) ∧ x i < y i := by
obtain ⟨hle, j, hlt⟩ := Pi.lt_def.1 hlt classical have : (x.neLocus y : Set ι).WellFoundedOn r := (x.neLocus y).finite_toSet.wellFoundedOn obtain ⟨i, hi, hl⟩ := this.has_min { i | x i < y i } ⟨⟨j, mem_neLocus.2 hlt.ne⟩, hlt⟩ refine ⟨i, fun k hk ↦ ⟨hle k, ?_⟩, hi⟩ exact of_not_not fun h ↦ hl ⟨k, mem_neLocus.2 (ne_of_not_le h).symm⟩ ((hle k).lt_of_not_le h) hk
false
import Mathlib.RingTheory.IntegralClosure import Mathlib.RingTheory.Localization.Integral #align_import ring_theory.integrally_closed from "leanprover-community/mathlib"@"d35b4ff446f1421bd551fafa4b8efd98ac3ac408" open scoped nonZeroDivisors Polynomial open Polynomial abbrev IsIntegrallyClosedIn (R A : Type*) [CommRing R] [CommRing A] [Algebra R A] := IsIntegralClosure R R A abbrev IsIntegrallyClosed (R : Type*) [CommRing R] := IsIntegrallyClosedIn R (FractionRing R) #align is_integrally_closed IsIntegrallyClosed section Iff variable {R : Type*} [CommRing R] variable {A B : Type*} [CommRing A] [CommRing B] [Algebra R A] [Algebra R B] theorem AlgHom.isIntegrallyClosedIn (f : A →ₐ[R] B) (hf : Function.Injective f) : IsIntegrallyClosedIn R B → IsIntegrallyClosedIn R A := by rintro ⟨inj, cl⟩ refine ⟨Function.Injective.of_comp (f := f) ?_, fun hx => ?_, ?_⟩ · convert inj aesop · obtain ⟨y, fx_eq⟩ := cl.mp ((isIntegral_algHom_iff f hf).mpr hx) aesop · rintro ⟨y, rfl⟩ apply (isIntegral_algHom_iff f hf).mp aesop theorem AlgEquiv.isIntegrallyClosedIn (e : A ≃ₐ[R] B) : IsIntegrallyClosedIn R A ↔ IsIntegrallyClosedIn R B := ⟨AlgHom.isIntegrallyClosedIn e.symm e.symm.injective, AlgHom.isIntegrallyClosedIn e e.injective⟩ variable (K : Type*) [CommRing K] [Algebra R K] [IsFractionRing R K] theorem isIntegrallyClosed_iff_isIntegrallyClosedIn : IsIntegrallyClosed R ↔ IsIntegrallyClosedIn R K := (IsLocalization.algEquiv R⁰ _ _).isIntegrallyClosedIn theorem isIntegrallyClosed_iff_isIntegralClosure : IsIntegrallyClosed R ↔ IsIntegralClosure R R K := isIntegrallyClosed_iff_isIntegrallyClosedIn K #align is_integrally_closed_iff_is_integral_closure isIntegrallyClosed_iff_isIntegralClosure
Mathlib/RingTheory/IntegrallyClosed.lean
110
120
theorem isIntegrallyClosedIn_iff {R A : Type*} [CommRing R] [CommRing A] [Algebra R A] : IsIntegrallyClosedIn R A ↔ Function.Injective (algebraMap R A) ∧ ∀ {x : A}, IsIntegral R x → ∃ y, algebraMap R A y = x := by
constructor · rintro ⟨_, cl⟩ aesop · rintro ⟨inj, cl⟩ refine ⟨inj, by aesop, ?_⟩ rintro ⟨y, rfl⟩ apply isIntegral_algebraMap
false
import Mathlib.Order.Monotone.Union import Mathlib.Algebra.Order.Group.Instances #align_import order.monotone.odd from "leanprover-community/mathlib"@"9116dd6709f303dcf781632e15fdef382b0fc579" open Set variable {G H : Type*} [LinearOrderedAddCommGroup G] [OrderedAddCommGroup H]
Mathlib/Order/Monotone/Odd.lean
26
30
theorem strictMono_of_odd_strictMonoOn_nonneg {f : G → H} (h₁ : ∀ x, f (-x) = -f x) (h₂ : StrictMonoOn f (Ici 0)) : StrictMono f := by
refine StrictMonoOn.Iic_union_Ici (fun x hx y hy hxy => neg_lt_neg_iff.1 ?_) h₂ rw [← h₁, ← h₁] exact h₂ (neg_nonneg.2 hy) (neg_nonneg.2 hx) (neg_lt_neg hxy)
false
import Mathlib.Data.List.Infix #align_import data.list.rdrop from "leanprover-community/mathlib"@"26f081a2fb920140ed5bc5cc5344e84bcc7cb2b2" -- Make sure we don't import algebra assert_not_exists Monoid variable {α : Type*} (p : α → Bool) (l : List α) (n : ℕ) namespace List def rdrop : List α := l.take (l.length - n) #align list.rdrop List.rdrop @[simp] theorem rdrop_nil : rdrop ([] : List α) n = [] := by simp [rdrop] #align list.rdrop_nil List.rdrop_nil @[simp] theorem rdrop_zero : rdrop l 0 = l := by simp [rdrop] #align list.rdrop_zero List.rdrop_zero theorem rdrop_eq_reverse_drop_reverse : l.rdrop n = reverse (l.reverse.drop n) := by rw [rdrop] induction' l using List.reverseRecOn with xs x IH generalizing n · simp · cases n · simp [take_append] · simp [take_append_eq_append_take, IH] #align list.rdrop_eq_reverse_drop_reverse List.rdrop_eq_reverse_drop_reverse @[simp] theorem rdrop_concat_succ (x : α) : rdrop (l ++ [x]) (n + 1) = rdrop l n := by simp [rdrop_eq_reverse_drop_reverse] #align list.rdrop_concat_succ List.rdrop_concat_succ def rtake : List α := l.drop (l.length - n) #align list.rtake List.rtake @[simp] theorem rtake_nil : rtake ([] : List α) n = [] := by simp [rtake] #align list.rtake_nil List.rtake_nil @[simp] theorem rtake_zero : rtake l 0 = [] := by simp [rtake] #align list.rtake_zero List.rtake_zero
Mathlib/Data/List/DropRight.lean
81
87
theorem rtake_eq_reverse_take_reverse : l.rtake n = reverse (l.reverse.take n) := by
rw [rtake] induction' l using List.reverseRecOn with xs x IH generalizing n · simp · cases n · exact drop_length _ · simp [drop_append_eq_append_drop, IH]
false
import Mathlib.Data.ENNReal.Basic import Mathlib.Topology.ContinuousFunction.Bounded import Mathlib.Topology.MetricSpace.Thickening #align_import topology.metric_space.thickened_indicator from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982" open scoped Classical open NNReal ENNReal Topology BoundedContinuousFunction open NNReal ENNReal Set Metric EMetric Filter noncomputable section thickenedIndicator variable {α : Type*} [PseudoEMetricSpace α] def thickenedIndicatorAux (δ : ℝ) (E : Set α) : α → ℝ≥0∞ := fun x : α => (1 : ℝ≥0∞) - infEdist x E / ENNReal.ofReal δ #align thickened_indicator_aux thickenedIndicatorAux theorem continuous_thickenedIndicatorAux {δ : ℝ} (δ_pos : 0 < δ) (E : Set α) : Continuous (thickenedIndicatorAux δ E) := by unfold thickenedIndicatorAux let f := fun x : α => (⟨1, infEdist x E / ENNReal.ofReal δ⟩ : ℝ≥0 × ℝ≥0∞) let sub := fun p : ℝ≥0 × ℝ≥0∞ => (p.1 : ℝ≥0∞) - p.2 rw [show (fun x : α => (1 : ℝ≥0∞) - infEdist x E / ENNReal.ofReal δ) = sub ∘ f by rfl] apply (@ENNReal.continuous_nnreal_sub 1).comp apply (ENNReal.continuous_div_const (ENNReal.ofReal δ) _).comp continuous_infEdist set_option tactic.skipAssignedInstances false in norm_num [δ_pos] #align continuous_thickened_indicator_aux continuous_thickenedIndicatorAux theorem thickenedIndicatorAux_le_one (δ : ℝ) (E : Set α) (x : α) : thickenedIndicatorAux δ E x ≤ 1 := by apply @tsub_le_self _ _ _ _ (1 : ℝ≥0∞) #align thickened_indicator_aux_le_one thickenedIndicatorAux_le_one theorem thickenedIndicatorAux_lt_top {δ : ℝ} {E : Set α} {x : α} : thickenedIndicatorAux δ E x < ∞ := lt_of_le_of_lt (thickenedIndicatorAux_le_one _ _ _) one_lt_top #align thickened_indicator_aux_lt_top thickenedIndicatorAux_lt_top theorem thickenedIndicatorAux_closure_eq (δ : ℝ) (E : Set α) : thickenedIndicatorAux δ (closure E) = thickenedIndicatorAux δ E := by simp (config := { unfoldPartialApp := true }) only [thickenedIndicatorAux, infEdist_closure] #align thickened_indicator_aux_closure_eq thickenedIndicatorAux_closure_eq theorem thickenedIndicatorAux_one (δ : ℝ) (E : Set α) {x : α} (x_in_E : x ∈ E) : thickenedIndicatorAux δ E x = 1 := by simp [thickenedIndicatorAux, infEdist_zero_of_mem x_in_E, tsub_zero] #align thickened_indicator_aux_one thickenedIndicatorAux_one theorem thickenedIndicatorAux_one_of_mem_closure (δ : ℝ) (E : Set α) {x : α} (x_mem : x ∈ closure E) : thickenedIndicatorAux δ E x = 1 := by rw [← thickenedIndicatorAux_closure_eq, thickenedIndicatorAux_one δ (closure E) x_mem] #align thickened_indicator_aux_one_of_mem_closure thickenedIndicatorAux_one_of_mem_closure theorem thickenedIndicatorAux_zero {δ : ℝ} (δ_pos : 0 < δ) (E : Set α) {x : α} (x_out : x ∉ thickening δ E) : thickenedIndicatorAux δ E x = 0 := by rw [thickening, mem_setOf_eq, not_lt] at x_out unfold thickenedIndicatorAux apply le_antisymm _ bot_le have key := tsub_le_tsub (@rfl _ (1 : ℝ≥0∞)).le (ENNReal.div_le_div x_out (@rfl _ (ENNReal.ofReal δ : ℝ≥0∞)).le) rw [ENNReal.div_self (ne_of_gt (ENNReal.ofReal_pos.mpr δ_pos)) ofReal_ne_top] at key simpa using key #align thickened_indicator_aux_zero thickenedIndicatorAux_zero theorem thickenedIndicatorAux_mono {δ₁ δ₂ : ℝ} (hle : δ₁ ≤ δ₂) (E : Set α) : thickenedIndicatorAux δ₁ E ≤ thickenedIndicatorAux δ₂ E := fun _ => tsub_le_tsub (@rfl ℝ≥0∞ 1).le (ENNReal.div_le_div rfl.le (ofReal_le_ofReal hle)) #align thickened_indicator_aux_mono thickenedIndicatorAux_mono theorem indicator_le_thickenedIndicatorAux (δ : ℝ) (E : Set α) : (E.indicator fun _ => (1 : ℝ≥0∞)) ≤ thickenedIndicatorAux δ E := by intro a by_cases h : a ∈ E · simp only [h, indicator_of_mem, thickenedIndicatorAux_one δ E h, le_refl] · simp only [h, indicator_of_not_mem, not_false_iff, zero_le] #align indicator_le_thickened_indicator_aux indicator_le_thickenedIndicatorAux theorem thickenedIndicatorAux_subset (δ : ℝ) {E₁ E₂ : Set α} (subset : E₁ ⊆ E₂) : thickenedIndicatorAux δ E₁ ≤ thickenedIndicatorAux δ E₂ := fun _ => tsub_le_tsub (@rfl ℝ≥0∞ 1).le (ENNReal.div_le_div (infEdist_anti subset) rfl.le) #align thickened_indicator_aux_subset thickenedIndicatorAux_subset
Mathlib/Topology/MetricSpace/ThickenedIndicator.lean
130
153
theorem thickenedIndicatorAux_tendsto_indicator_closure {δseq : ℕ → ℝ} (δseq_lim : Tendsto δseq atTop (𝓝 0)) (E : Set α) : Tendsto (fun n => thickenedIndicatorAux (δseq n) E) atTop (𝓝 (indicator (closure E) fun _ => (1 : ℝ≥0∞))) := by
rw [tendsto_pi_nhds] intro x by_cases x_mem_closure : x ∈ closure E · simp_rw [thickenedIndicatorAux_one_of_mem_closure _ E x_mem_closure] rw [show (indicator (closure E) fun _ => (1 : ℝ≥0∞)) x = 1 by simp only [x_mem_closure, indicator_of_mem]] exact tendsto_const_nhds · rw [show (closure E).indicator (fun _ => (1 : ℝ≥0∞)) x = 0 by simp only [x_mem_closure, indicator_of_not_mem, not_false_iff]] rcases exists_real_pos_lt_infEdist_of_not_mem_closure x_mem_closure with ⟨ε, ⟨ε_pos, ε_lt⟩⟩ rw [Metric.tendsto_nhds] at δseq_lim specialize δseq_lim ε ε_pos simp only [dist_zero_right, Real.norm_eq_abs, eventually_atTop, ge_iff_le] at δseq_lim rcases δseq_lim with ⟨N, hN⟩ apply @tendsto_atTop_of_eventually_const _ _ _ _ _ _ _ N intro n n_large have key : x ∉ thickening ε E := by simpa only [thickening, mem_setOf_eq, not_lt] using ε_lt.le refine le_antisymm ?_ bot_le apply (thickenedIndicatorAux_mono (lt_of_abs_lt (hN n n_large)).le E x).trans exact (thickenedIndicatorAux_zero ε_pos E key).le
false
import Mathlib.SetTheory.Cardinal.Finite #align_import data.set.ncard from "leanprover-community/mathlib"@"74c2af38a828107941029b03839882c5c6f87a04" namespace Set variable {α β : Type*} {s t : Set α} noncomputable def encard (s : Set α) : ℕ∞ := PartENat.withTopEquiv (PartENat.card s) @[simp] theorem encard_univ_coe (s : Set α) : encard (univ : Set s) = encard s := by rw [encard, encard, PartENat.card_congr (Equiv.Set.univ ↑s)] theorem encard_univ (α : Type*) : encard (univ : Set α) = PartENat.withTopEquiv (PartENat.card α) := by rw [encard, PartENat.card_congr (Equiv.Set.univ α)] theorem Finite.encard_eq_coe_toFinset_card (h : s.Finite) : s.encard = h.toFinset.card := by have := h.fintype rw [encard, PartENat.card_eq_coe_fintype_card, PartENat.withTopEquiv_natCast, toFinite_toFinset, toFinset_card] theorem encard_eq_coe_toFinset_card (s : Set α) [Fintype s] : encard s = s.toFinset.card := by have h := toFinite s rw [h.encard_eq_coe_toFinset_card, toFinite_toFinset] theorem encard_coe_eq_coe_finsetCard (s : Finset α) : encard (s : Set α) = s.card := by rw [Finite.encard_eq_coe_toFinset_card (Finset.finite_toSet s)]; simp theorem Infinite.encard_eq {s : Set α} (h : s.Infinite) : s.encard = ⊤ := by have := h.to_subtype rw [encard, ← PartENat.withTopEquiv.symm.injective.eq_iff, Equiv.symm_apply_apply, PartENat.withTopEquiv_symm_top, PartENat.card_eq_top_of_infinite] @[simp] theorem encard_eq_zero : s.encard = 0 ↔ s = ∅ := by rw [encard, ← PartENat.withTopEquiv.symm.injective.eq_iff, Equiv.symm_apply_apply, PartENat.withTopEquiv_symm_zero, PartENat.card_eq_zero_iff_empty, isEmpty_subtype, eq_empty_iff_forall_not_mem] @[simp] theorem encard_empty : (∅ : Set α).encard = 0 := by rw [encard_eq_zero] theorem nonempty_of_encard_ne_zero (h : s.encard ≠ 0) : s.Nonempty := by rwa [nonempty_iff_ne_empty, Ne, ← encard_eq_zero] theorem encard_ne_zero : s.encard ≠ 0 ↔ s.Nonempty := by rw [ne_eq, encard_eq_zero, nonempty_iff_ne_empty] @[simp] theorem encard_pos : 0 < s.encard ↔ s.Nonempty := by rw [pos_iff_ne_zero, encard_ne_zero] @[simp] theorem encard_singleton (e : α) : ({e} : Set α).encard = 1 := by rw [encard, ← PartENat.withTopEquiv.symm.injective.eq_iff, Equiv.symm_apply_apply, PartENat.card_eq_coe_fintype_card, Fintype.card_ofSubsingleton, Nat.cast_one]; rfl theorem encard_union_eq (h : Disjoint s t) : (s ∪ t).encard = s.encard + t.encard := by classical have e := (Equiv.Set.union (by rwa [subset_empty_iff, ← disjoint_iff_inter_eq_empty])).symm simp [encard, ← PartENat.card_congr e, PartENat.card_sum, PartENat.withTopEquiv] theorem encard_insert_of_not_mem {a : α} (has : a ∉ s) : (insert a s).encard = s.encard + 1 := by rw [← union_singleton, encard_union_eq (by simpa), encard_singleton] theorem Finite.encard_lt_top (h : s.Finite) : s.encard < ⊤ := by refine h.induction_on (by simp) ?_ rintro a t hat _ ht' rw [encard_insert_of_not_mem hat] exact lt_tsub_iff_right.1 ht' theorem Finite.encard_eq_coe (h : s.Finite) : s.encard = ENat.toNat s.encard := (ENat.coe_toNat h.encard_lt_top.ne).symm theorem Finite.exists_encard_eq_coe (h : s.Finite) : ∃ (n : ℕ), s.encard = n := ⟨_, h.encard_eq_coe⟩ @[simp] theorem encard_lt_top_iff : s.encard < ⊤ ↔ s.Finite := ⟨fun h ↦ by_contra fun h' ↦ h.ne (Infinite.encard_eq h'), Finite.encard_lt_top⟩ @[simp] theorem encard_eq_top_iff : s.encard = ⊤ ↔ s.Infinite := by rw [← not_iff_not, ← Ne, ← lt_top_iff_ne_top, encard_lt_top_iff, not_infinite] theorem encard_ne_top_iff : s.encard ≠ ⊤ ↔ s.Finite := by simp theorem finite_of_encard_le_coe {k : ℕ} (h : s.encard ≤ k) : s.Finite := by rw [← encard_lt_top_iff]; exact h.trans_lt (WithTop.coe_lt_top _) theorem finite_of_encard_eq_coe {k : ℕ} (h : s.encard = k) : s.Finite := finite_of_encard_le_coe h.le theorem encard_le_coe_iff {k : ℕ} : s.encard ≤ k ↔ s.Finite ∧ ∃ (n₀ : ℕ), s.encard = n₀ ∧ n₀ ≤ k := ⟨fun h ↦ ⟨finite_of_encard_le_coe h, by rwa [ENat.le_coe_iff] at h⟩, fun ⟨_,⟨n₀,hs, hle⟩⟩ ↦ by rwa [hs, Nat.cast_le]⟩ section SmallSets
Mathlib/Data/Set/Card.lean
286
288
theorem encard_pair {x y : α} (hne : x ≠ y) : ({x, y} : Set α).encard = 2 := by
rw [encard_insert_of_not_mem (by simpa), ← one_add_one_eq_two, WithTop.add_right_cancel_iff WithTop.one_ne_top, encard_singleton]
false
import Mathlib.Algebra.Order.Sub.Defs import Mathlib.Data.Finset.Basic import Mathlib.Order.Interval.Finset.Defs open Function namespace Finset class HasAntidiagonal (A : Type*) [AddMonoid A] where antidiagonal : A → Finset (A × A) mem_antidiagonal {n} {a} : a ∈ antidiagonal n ↔ a.fst + a.snd = n export HasAntidiagonal (antidiagonal mem_antidiagonal) attribute [simp] mem_antidiagonal variable {A : Type*} instance [AddMonoid A] : Subsingleton (HasAntidiagonal A) := ⟨by rintro ⟨a, ha⟩ ⟨b, hb⟩ congr with n xy rw [ha, hb]⟩ -- The goal of this lemma is to allow to rewrite antidiagonal -- when the decidability instances obsucate Lean lemma hasAntidiagonal_congr (A : Type*) [AddMonoid A] [H1 : HasAntidiagonal A] [H2 : HasAntidiagonal A] : H1.antidiagonal = H2.antidiagonal := by congr!; apply Subsingleton.elim theorem swap_mem_antidiagonal [AddCommMonoid A] [HasAntidiagonal A] {n : A} {xy : A × A}: xy.swap ∈ antidiagonal n ↔ xy ∈ antidiagonal n := by simp [add_comm] @[simp] theorem map_prodComm_antidiagonal [AddCommMonoid A] [HasAntidiagonal A] {n : A} : (antidiagonal n).map (Equiv.prodComm A A) = antidiagonal n := Finset.ext fun ⟨a, b⟩ => by simp [add_comm] @[simp] theorem map_swap_antidiagonal [AddCommMonoid A] [HasAntidiagonal A] {n : A} : (antidiagonal n).map ⟨Prod.swap, Prod.swap_injective⟩ = antidiagonal n := map_prodComm_antidiagonal #align finset.nat.map_swap_antidiagonal Finset.map_swap_antidiagonal section CanonicallyOrderedAddCommMonoid variable [CanonicallyOrderedAddCommMonoid A] [HasAntidiagonal A] @[simp]
Mathlib/Data/Finset/Antidiagonal.lean
131
133
theorem antidiagonal_zero : antidiagonal (0 : A) = {(0, 0)} := by
ext ⟨x, y⟩ simp
false
import Mathlib.Geometry.Euclidean.Inversion.Basic import Mathlib.Analysis.InnerProductSpace.Calculus import Mathlib.Analysis.Calculus.Deriv.Inv import Mathlib.Tactic.AdaptationNote open Metric Function AffineMap Set AffineSubspace open scoped Topology RealInnerProductSpace variable {E F : Type*} [NormedAddCommGroup E] [NormedSpace ℝ E] [NormedAddCommGroup F] [InnerProductSpace ℝ F] open EuclideanGeometry namespace EuclideanGeometry variable {a b c d x y z : F} {r R : ℝ}
Mathlib/Geometry/Euclidean/Inversion/Calculus.lean
87
108
theorem hasFDerivAt_inversion (hx : x ≠ c) : HasFDerivAt (inversion c R) ((R / dist x c) ^ 2 • (reflection (ℝ ∙ (x - c))ᗮ : F →L[ℝ] F)) x := by
rcases add_left_surjective c x with ⟨x, rfl⟩ have : HasFDerivAt (inversion c R) (?_ : F →L[ℝ] F) (c + x) := by #adaptation_note /-- nightly-2024-03-16: simp was simp (config := { unfoldPartialApp := true }) only [inversion] -/ simp only [inversion_def] simp_rw [dist_eq_norm, div_pow, div_eq_mul_inv] have A := (hasFDerivAt_id (𝕜 := ℝ) (c + x)).sub_const c have B := ((hasDerivAt_inv <| by simpa using hx).comp_hasFDerivAt _ A.norm_sq).const_mul (R ^ 2) exact (B.smul A).add_const c refine this.congr_fderiv (LinearMap.ext_on_codisjoint (Submodule.isCompl_orthogonal_of_completeSpace (K := ℝ ∙ x)).codisjoint (LinearMap.eqOn_span' ?_) fun y hy ↦ ?_) · have : ((‖x‖ ^ 2) ^ 2)⁻¹ * (‖x‖ ^ 2) = (‖x‖ ^ 2)⁻¹ := by rw [← div_eq_inv_mul, sq (‖x‖ ^ 2), div_self_mul_self'] simp [reflection_orthogonalComplement_singleton_eq_neg, real_inner_self_eq_norm_sq, two_mul, this, div_eq_mul_inv, mul_add, add_smul, mul_pow] · simp [Submodule.mem_orthogonal_singleton_iff_inner_right.1 hy, reflection_mem_subspace_eq_self hy, div_eq_mul_inv, mul_pow]
false
import Mathlib.Analysis.Normed.Group.Hom import Mathlib.Analysis.SpecificLimits.Normed #align_import analysis.normed.group.controlled_closure from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982" open Filter Finset open Topology variable {G : Type*} [NormedAddCommGroup G] [CompleteSpace G] variable {H : Type*} [NormedAddCommGroup H]
Mathlib/Analysis/Normed/Group/ControlledClosure.lean
32
106
theorem controlled_closure_of_complete {f : NormedAddGroupHom G H} {K : AddSubgroup H} {C ε : ℝ} (hC : 0 < C) (hε : 0 < ε) (hyp : f.SurjectiveOnWith K C) : f.SurjectiveOnWith K.topologicalClosure (C + ε) := by
rintro (h : H) (h_in : h ∈ K.topologicalClosure) -- We first get rid of the easy case where `h = 0`. by_cases hyp_h : h = 0 · rw [hyp_h] use 0 simp /- The desired preimage will be constructed as the sum of a series. Convergence of the series will be guaranteed by completeness of `G`. We first write `h` as the sum of a sequence `v` of elements of `K` which starts close to `h` and then quickly goes to zero. The sequence `b` below quantifies this. -/ set b : ℕ → ℝ := fun i => (1 / 2) ^ i * (ε * ‖h‖ / 2) / C have b_pos (i) : 0 < b i := by field_simp [b, hC, hyp_h] obtain ⟨v : ℕ → H, lim_v : Tendsto (fun n : ℕ => ∑ k ∈ range (n + 1), v k) atTop (𝓝 h), v_in : ∀ n, v n ∈ K, hv₀ : ‖v 0 - h‖ < b 0, hv : ∀ n > 0, ‖v n‖ < b n⟩ := controlled_sum_of_mem_closure h_in b_pos /- The controlled surjectivity assumption on `f` allows to build preimages `u n` for all elements `v n` of the `v` sequence. -/ have : ∀ n, ∃ m' : G, f m' = v n ∧ ‖m'‖ ≤ C * ‖v n‖ := fun n : ℕ => hyp (v n) (v_in n) choose u hu hnorm_u using this /- The desired series `s` is then obtained by summing `u`. We then check our choice of `b` ensures `s` is Cauchy. -/ set s : ℕ → G := fun n => ∑ k ∈ range (n + 1), u k have : CauchySeq s := by apply NormedAddCommGroup.cauchy_series_of_le_geometric'' (by norm_num) one_half_lt_one · rintro n (hn : n ≥ 1) calc ‖u n‖ ≤ C * ‖v n‖ := hnorm_u n _ ≤ C * b n := by gcongr; exact (hv _ <| Nat.succ_le_iff.mp hn).le _ = (1 / 2) ^ n * (ε * ‖h‖ / 2) := by simp [mul_div_cancel₀ _ hC.ne.symm] _ = ε * ‖h‖ / 2 * (1 / 2) ^ n := mul_comm _ _ -- We now show that the limit `g` of `s` is the desired preimage. obtain ⟨g : G, hg⟩ := cauchySeq_tendsto_of_complete this refine ⟨g, ?_, ?_⟩ · -- We indeed get a preimage. First note: have : f ∘ s = fun n => ∑ k ∈ range (n + 1), v k := by ext n simp [s, map_sum, hu] /- In the above equality, the left-hand-side converges to `f g` by continuity of `f` and definition of `g` while the right-hand-side converges to `h` by construction of `v` so `g` is indeed a preimage of `h`. -/ rw [← this] at lim_v exact tendsto_nhds_unique ((f.continuous.tendsto g).comp hg) lim_v · -- Then we need to estimate the norm of `g`, using our careful choice of `b`. suffices ∀ n, ‖s n‖ ≤ (C + ε) * ‖h‖ from le_of_tendsto' (continuous_norm.continuousAt.tendsto.comp hg) this intro n have hnorm₀ : ‖u 0‖ ≤ C * b 0 + C * ‖h‖ := by have := calc ‖v 0‖ ≤ ‖h‖ + ‖v 0 - h‖ := norm_le_insert' _ _ _ ≤ ‖h‖ + b 0 := by gcongr calc ‖u 0‖ ≤ C * ‖v 0‖ := hnorm_u 0 _ ≤ C * (‖h‖ + b 0) := by gcongr _ = C * b 0 + C * ‖h‖ := by rw [add_comm, mul_add] have : (∑ k ∈ range (n + 1), C * b k) ≤ ε * ‖h‖ := calc (∑ k ∈ range (n + 1), C * b k) _ = (∑ k ∈ range (n + 1), (1 / 2 : ℝ) ^ k) * (ε * ‖h‖ / 2) := by simp only [mul_div_cancel₀ _ hC.ne.symm, ← sum_mul] _ ≤ 2 * (ε * ‖h‖ / 2) := by gcongr; apply sum_geometric_two_le _ = ε * ‖h‖ := mul_div_cancel₀ _ two_ne_zero calc ‖s n‖ ≤ ∑ k ∈ range (n + 1), ‖u k‖ := norm_sum_le _ _ _ = (∑ k ∈ range n, ‖u (k + 1)‖) + ‖u 0‖ := sum_range_succ' _ _ _ ≤ (∑ k ∈ range n, C * ‖v (k + 1)‖) + ‖u 0‖ := by gcongr; apply hnorm_u _ ≤ (∑ k ∈ range n, C * b (k + 1)) + (C * b 0 + C * ‖h‖) := by gcongr with k; exact (hv _ k.succ_pos).le _ = (∑ k ∈ range (n + 1), C * b k) + C * ‖h‖ := by rw [← add_assoc, sum_range_succ'] _ ≤ (C + ε) * ‖h‖ := by rw [add_comm, add_mul] apply add_le_add_left this
false
import Mathlib.Analysis.SpecialFunctions.Complex.Circle import Mathlib.Geometry.Euclidean.Angle.Oriented.Basic #align_import geometry.euclidean.angle.oriented.rotation from "leanprover-community/mathlib"@"f0c8bf9245297a541f468be517f1bde6195105e9" noncomputable section open FiniteDimensional Complex open scoped Real RealInnerProductSpace ComplexConjugate namespace Orientation attribute [local instance] Complex.finrank_real_complex_fact variable {V V' : Type*} variable [NormedAddCommGroup V] [NormedAddCommGroup V'] variable [InnerProductSpace ℝ V] [InnerProductSpace ℝ V'] variable [Fact (finrank ℝ V = 2)] [Fact (finrank ℝ V' = 2)] (o : Orientation ℝ V (Fin 2)) local notation "J" => o.rightAngleRotation def rotationAux (θ : Real.Angle) : V →ₗᵢ[ℝ] V := LinearMap.isometryOfInner (Real.Angle.cos θ • LinearMap.id + Real.Angle.sin θ • (LinearIsometryEquiv.toLinearEquiv J).toLinearMap) (by intro x y simp only [RCLike.conj_to_real, id, LinearMap.smul_apply, LinearMap.add_apply, LinearMap.id_coe, LinearEquiv.coe_coe, LinearIsometryEquiv.coe_toLinearEquiv, Orientation.areaForm_rightAngleRotation_left, Orientation.inner_rightAngleRotation_left, Orientation.inner_rightAngleRotation_right, inner_add_left, inner_smul_left, inner_add_right, inner_smul_right] linear_combination inner (𝕜 := ℝ) x y * θ.cos_sq_add_sin_sq) #align orientation.rotation_aux Orientation.rotationAux @[simp] theorem rotationAux_apply (θ : Real.Angle) (x : V) : o.rotationAux θ x = Real.Angle.cos θ • x + Real.Angle.sin θ • J x := rfl #align orientation.rotation_aux_apply Orientation.rotationAux_apply def rotation (θ : Real.Angle) : V ≃ₗᵢ[ℝ] V := LinearIsometryEquiv.ofLinearIsometry (o.rotationAux θ) (Real.Angle.cos θ • LinearMap.id - Real.Angle.sin θ • (LinearIsometryEquiv.toLinearEquiv J).toLinearMap) (by ext x convert congr_arg (fun t : ℝ => t • x) θ.cos_sq_add_sin_sq using 1 · simp only [o.rightAngleRotation_rightAngleRotation, o.rotationAux_apply, Function.comp_apply, id, LinearEquiv.coe_coe, LinearIsometry.coe_toLinearMap, LinearIsometryEquiv.coe_toLinearEquiv, map_smul, map_sub, LinearMap.coe_comp, LinearMap.id_coe, LinearMap.smul_apply, LinearMap.sub_apply, ← mul_smul, add_smul, smul_add, smul_neg, smul_sub, mul_comm, sq] abel · simp) (by ext x convert congr_arg (fun t : ℝ => t • x) θ.cos_sq_add_sin_sq using 1 · simp only [o.rightAngleRotation_rightAngleRotation, o.rotationAux_apply, Function.comp_apply, id, LinearEquiv.coe_coe, LinearIsometry.coe_toLinearMap, LinearIsometryEquiv.coe_toLinearEquiv, map_add, map_smul, LinearMap.coe_comp, LinearMap.id_coe, LinearMap.smul_apply, LinearMap.sub_apply, add_smul, smul_neg, smul_sub, smul_smul] ring_nf abel · simp) #align orientation.rotation Orientation.rotation theorem rotation_apply (θ : Real.Angle) (x : V) : o.rotation θ x = Real.Angle.cos θ • x + Real.Angle.sin θ • J x := rfl #align orientation.rotation_apply Orientation.rotation_apply theorem rotation_symm_apply (θ : Real.Angle) (x : V) : (o.rotation θ).symm x = Real.Angle.cos θ • x - Real.Angle.sin θ • J x := rfl #align orientation.rotation_symm_apply Orientation.rotation_symm_apply theorem rotation_eq_matrix_toLin (θ : Real.Angle) {x : V} (hx : x ≠ 0) : (o.rotation θ).toLinearMap = Matrix.toLin (o.basisRightAngleRotation x hx) (o.basisRightAngleRotation x hx) !![θ.cos, -θ.sin; θ.sin, θ.cos] := by apply (o.basisRightAngleRotation x hx).ext intro i fin_cases i · rw [Matrix.toLin_self] simp [rotation_apply, Fin.sum_univ_succ] · rw [Matrix.toLin_self] simp [rotation_apply, Fin.sum_univ_succ, add_comm] #align orientation.rotation_eq_matrix_to_lin Orientation.rotation_eq_matrix_toLin @[simp] theorem det_rotation (θ : Real.Angle) : LinearMap.det (o.rotation θ).toLinearMap = 1 := by haveI : Nontrivial V := FiniteDimensional.nontrivial_of_finrank_eq_succ (@Fact.out (finrank ℝ V = 2) _) obtain ⟨x, hx⟩ : ∃ x, x ≠ (0 : V) := exists_ne (0 : V) rw [o.rotation_eq_matrix_toLin θ hx] simpa [sq] using θ.cos_sq_add_sin_sq #align orientation.det_rotation Orientation.det_rotation @[simp] theorem linearEquiv_det_rotation (θ : Real.Angle) : LinearEquiv.det (o.rotation θ).toLinearEquiv = 1 := Units.ext <| by -- Porting note: Lean can't see through `LinearEquiv.coe_det` and needed the rewrite -- in mathlib3 this was just `units.ext <| o.det_rotation θ` simpa only [LinearEquiv.coe_det, Units.val_one] using o.det_rotation θ #align orientation.linear_equiv_det_rotation Orientation.linearEquiv_det_rotation @[simp] theorem rotation_symm (θ : Real.Angle) : (o.rotation θ).symm = o.rotation (-θ) := by ext; simp [o.rotation_apply, o.rotation_symm_apply, sub_eq_add_neg] #align orientation.rotation_symm Orientation.rotation_symm @[simp] theorem rotation_zero : o.rotation 0 = LinearIsometryEquiv.refl ℝ V := by ext; simp [rotation] #align orientation.rotation_zero Orientation.rotation_zero @[simp]
Mathlib/Geometry/Euclidean/Angle/Oriented/Rotation.lean
145
147
theorem rotation_pi : o.rotation π = LinearIsometryEquiv.neg ℝ := by
ext x simp [rotation]
false
import Mathlib.Algebra.Quaternion import Mathlib.Analysis.InnerProductSpace.Basic import Mathlib.Analysis.InnerProductSpace.PiL2 import Mathlib.Topology.Algebra.Algebra #align_import analysis.quaternion from "leanprover-community/mathlib"@"07992a1d1f7a4176c6d3f160209608be4e198566" @[inherit_doc] scoped[Quaternion] notation "ℍ" => Quaternion ℝ open scoped RealInnerProductSpace namespace Quaternion instance : Inner ℝ ℍ := ⟨fun a b => (a * star b).re⟩ theorem inner_self (a : ℍ) : ⟪a, a⟫ = normSq a := rfl #align quaternion.inner_self Quaternion.inner_self theorem inner_def (a b : ℍ) : ⟪a, b⟫ = (a * star b).re := rfl #align quaternion.inner_def Quaternion.inner_def noncomputable instance : NormedAddCommGroup ℍ := @InnerProductSpace.Core.toNormedAddCommGroup ℝ ℍ _ _ _ { toInner := inferInstance conj_symm := fun x y => by simp [inner_def, mul_comm] nonneg_re := fun x => normSq_nonneg definite := fun x => normSq_eq_zero.1 add_left := fun x y z => by simp only [inner_def, add_mul, add_re] smul_left := fun x y r => by simp [inner_def] } noncomputable instance : InnerProductSpace ℝ ℍ := InnerProductSpace.ofCore _ theorem normSq_eq_norm_mul_self (a : ℍ) : normSq a = ‖a‖ * ‖a‖ := by rw [← inner_self, real_inner_self_eq_norm_mul_norm] #align quaternion.norm_sq_eq_norm_sq Quaternion.normSq_eq_norm_mul_self instance : NormOneClass ℍ := ⟨by rw [norm_eq_sqrt_real_inner, inner_self, normSq.map_one, Real.sqrt_one]⟩ @[simp, norm_cast] theorem norm_coe (a : ℝ) : ‖(a : ℍ)‖ = ‖a‖ := by rw [norm_eq_sqrt_real_inner, inner_self, normSq_coe, Real.sqrt_sq_eq_abs, Real.norm_eq_abs] #align quaternion.norm_coe Quaternion.norm_coe @[simp, norm_cast] theorem nnnorm_coe (a : ℝ) : ‖(a : ℍ)‖₊ = ‖a‖₊ := Subtype.ext <| norm_coe a #align quaternion.nnnorm_coe Quaternion.nnnorm_coe @[simp, nolint simpNF] -- Porting note (#10959): simp cannot prove this theorem norm_star (a : ℍ) : ‖star a‖ = ‖a‖ := by simp_rw [norm_eq_sqrt_real_inner, inner_self, normSq_star] #align quaternion.norm_star Quaternion.norm_star @[simp, nolint simpNF] -- Porting note (#10959): simp cannot prove this theorem nnnorm_star (a : ℍ) : ‖star a‖₊ = ‖a‖₊ := Subtype.ext <| norm_star a #align quaternion.nnnorm_star Quaternion.nnnorm_star noncomputable instance : NormedDivisionRing ℍ where dist_eq _ _ := rfl norm_mul' a b := by simp only [norm_eq_sqrt_real_inner, inner_self, normSq.map_mul] exact Real.sqrt_mul normSq_nonneg _ -- Porting note: added `noncomputable` noncomputable instance : NormedAlgebra ℝ ℍ where norm_smul_le := norm_smul_le toAlgebra := Quaternion.algebra instance : CstarRing ℍ where norm_star_mul_self {x} := (norm_mul _ _).trans <| congr_arg (· * ‖x‖) (norm_star x) @[coe] def coeComplex (z : ℂ) : ℍ := ⟨z.re, z.im, 0, 0⟩ instance : Coe ℂ ℍ := ⟨coeComplex⟩ @[simp, norm_cast] theorem coeComplex_re (z : ℂ) : (z : ℍ).re = z.re := rfl #align quaternion.coe_complex_re Quaternion.coeComplex_re @[simp, norm_cast] theorem coeComplex_imI (z : ℂ) : (z : ℍ).imI = z.im := rfl #align quaternion.coe_complex_im_i Quaternion.coeComplex_imI @[simp, norm_cast] theorem coeComplex_imJ (z : ℂ) : (z : ℍ).imJ = 0 := rfl #align quaternion.coe_complex_im_j Quaternion.coeComplex_imJ @[simp, norm_cast] theorem coeComplex_imK (z : ℂ) : (z : ℍ).imK = 0 := rfl #align quaternion.coe_complex_im_k Quaternion.coeComplex_imK @[simp, norm_cast] theorem coeComplex_add (z w : ℂ) : ↑(z + w) = (z + w : ℍ) := by ext <;> simp #align quaternion.coe_complex_add Quaternion.coeComplex_add @[simp, norm_cast]
Mathlib/Analysis/Quaternion.lean
136
136
theorem coeComplex_mul (z w : ℂ) : ↑(z * w) = (z * w : ℍ) := by
ext <;> simp
false
import Mathlib.Control.Functor import Mathlib.Tactic.Common #align_import control.bifunctor from "leanprover-community/mathlib"@"dc1525fb3ef6eb4348fb1749c302d8abc303d34a" universe u₀ u₁ u₂ v₀ v₁ v₂ open Function class Bifunctor (F : Type u₀ → Type u₁ → Type u₂) where bimap : ∀ {α α' β β'}, (α → α') → (β → β') → F α β → F α' β' #align bifunctor Bifunctor export Bifunctor (bimap) class LawfulBifunctor (F : Type u₀ → Type u₁ → Type u₂) [Bifunctor F] : Prop where id_bimap : ∀ {α β} (x : F α β), bimap id id x = x bimap_bimap : ∀ {α₀ α₁ α₂ β₀ β₁ β₂} (f : α₀ → α₁) (f' : α₁ → α₂) (g : β₀ → β₁) (g' : β₁ → β₂) (x : F α₀ β₀), bimap f' g' (bimap f g x) = bimap (f' ∘ f) (g' ∘ g) x #align is_lawful_bifunctor LawfulBifunctor export LawfulBifunctor (id_bimap bimap_bimap) attribute [higher_order bimap_id_id] id_bimap #align is_lawful_bifunctor.bimap_id_id LawfulBifunctor.bimap_id_id attribute [higher_order bimap_comp_bimap] bimap_bimap #align is_lawful_bifunctor.bimap_comp_bimap LawfulBifunctor.bimap_comp_bimap export LawfulBifunctor (bimap_id_id bimap_comp_bimap) variable {F : Type u₀ → Type u₁ → Type u₂} [Bifunctor F] namespace Bifunctor abbrev fst {α α' β} (f : α → α') : F α β → F α' β := bimap f id #align bifunctor.fst Bifunctor.fst abbrev snd {α β β'} (f : β → β') : F α β → F α β' := bimap id f #align bifunctor.snd Bifunctor.snd variable [LawfulBifunctor F] @[higher_order fst_id] theorem id_fst : ∀ {α β} (x : F α β), fst id x = x := @id_bimap _ _ _ #align bifunctor.id_fst Bifunctor.id_fst #align bifunctor.fst_id Bifunctor.fst_id @[higher_order snd_id] theorem id_snd : ∀ {α β} (x : F α β), snd id x = x := @id_bimap _ _ _ #align bifunctor.id_snd Bifunctor.id_snd #align bifunctor.snd_id Bifunctor.snd_id @[higher_order fst_comp_fst] theorem comp_fst {α₀ α₁ α₂ β} (f : α₀ → α₁) (f' : α₁ → α₂) (x : F α₀ β) : fst f' (fst f x) = fst (f' ∘ f) x := by simp [fst, bimap_bimap] #align bifunctor.comp_fst Bifunctor.comp_fst #align bifunctor.fst_comp_fst Bifunctor.fst_comp_fst @[higher_order fst_comp_snd] theorem fst_snd {α₀ α₁ β₀ β₁} (f : α₀ → α₁) (f' : β₀ → β₁) (x : F α₀ β₀) : fst f (snd f' x) = bimap f f' x := by simp [fst, bimap_bimap] #align bifunctor.fst_snd Bifunctor.fst_snd #align bifunctor.fst_comp_snd Bifunctor.fst_comp_snd @[higher_order snd_comp_fst]
Mathlib/Control/Bifunctor.lean
98
99
theorem snd_fst {α₀ α₁ β₀ β₁} (f : α₀ → α₁) (f' : β₀ → β₁) (x : F α₀ β₀) : snd f' (fst f x) = bimap f f' x := by
simp [snd, bimap_bimap]
false
import Mathlib.LinearAlgebra.TensorAlgebra.Basic import Mathlib.LinearAlgebra.TensorPower #align_import linear_algebra.tensor_algebra.to_tensor_power from "leanprover-community/mathlib"@"d97a0c9f7a7efe6d76d652c5a6b7c9c634b70e0a" suppress_compilation open scoped DirectSum TensorProduct variable {R M : Type*} [CommSemiring R] [AddCommMonoid M] [Module R M] namespace TensorPower def toTensorAlgebra {n} : ⨂[R]^n M →ₗ[R] TensorAlgebra R M := PiTensorProduct.lift (TensorAlgebra.tprod R M n) #align tensor_power.to_tensor_algebra TensorPower.toTensorAlgebra @[simp] theorem toTensorAlgebra_tprod {n} (x : Fin n → M) : TensorPower.toTensorAlgebra (PiTensorProduct.tprod R x) = TensorAlgebra.tprod R M n x := PiTensorProduct.lift.tprod _ #align tensor_power.to_tensor_algebra_tprod TensorPower.toTensorAlgebra_tprod @[simp] theorem toTensorAlgebra_gOne : TensorPower.toTensorAlgebra (@GradedMonoid.GOne.one _ (fun n => ⨂[R]^n M) _ _) = 1 := TensorPower.toTensorAlgebra_tprod _ #align tensor_power.to_tensor_algebra_ghas_one TensorPower.toTensorAlgebra_gOne @[simp] theorem toTensorAlgebra_gMul {i j} (a : (⨂[R]^i) M) (b : (⨂[R]^j) M) : TensorPower.toTensorAlgebra (@GradedMonoid.GMul.mul _ (fun n => ⨂[R]^n M) _ _ _ _ a b) = TensorPower.toTensorAlgebra a * TensorPower.toTensorAlgebra b := by -- change `a` and `b` to `tprod R a` and `tprod R b` rw [TensorPower.gMul_eq_coe_linearMap, ← LinearMap.compr₂_apply, ← @LinearMap.mul_apply' R, ← LinearMap.compl₂_apply, ← LinearMap.comp_apply] refine LinearMap.congr_fun (LinearMap.congr_fun ?_ a) b clear! a b ext (a b) -- Porting note: pulled the next two lines out of the long `simp only` below. simp only [LinearMap.compMultilinearMap_apply] rw [LinearMap.compr₂_apply, ← gMul_eq_coe_linearMap] simp only [LinearMap.compr₂_apply, LinearMap.mul_apply', LinearMap.compl₂_apply, LinearMap.comp_apply, LinearMap.compMultilinearMap_apply, PiTensorProduct.lift.tprod, TensorPower.tprod_mul_tprod, TensorPower.toTensorAlgebra_tprod, TensorAlgebra.tprod_apply, ← gMul_eq_coe_linearMap] refine Eq.trans ?_ List.prod_append congr -- Porting note: `erw` for `Function.comp` erw [← List.map_ofFn _ (TensorAlgebra.ι R), ← List.map_ofFn _ (TensorAlgebra.ι R), ← List.map_ofFn _ (TensorAlgebra.ι R), ← List.map_append, List.ofFn_fin_append] #align tensor_power.to_tensor_algebra_ghas_mul TensorPower.toTensorAlgebra_gMul @[simp]
Mathlib/LinearAlgebra/TensorAlgebra/ToTensorPower.lean
68
72
theorem toTensorAlgebra_galgebra_toFun (r : R) : TensorPower.toTensorAlgebra (DirectSum.GAlgebra.toFun (R := R) (A := fun n => ⨂[R]^n M) r) = algebraMap _ _ r := by
rw [TensorPower.galgebra_toFun_def, TensorPower.algebraMap₀_eq_smul_one, LinearMap.map_smul, TensorPower.toTensorAlgebra_gOne, Algebra.algebraMap_eq_smul_one]
false
import Mathlib.CategoryTheory.Category.Grpd import Mathlib.CategoryTheory.Groupoid import Mathlib.Topology.Category.TopCat.Basic import Mathlib.Topology.Homotopy.Path import Mathlib.Data.Set.Subsingleton #align_import algebraic_topology.fundamental_groupoid.basic from "leanprover-community/mathlib"@"3d7987cda72abc473c7cdbbb075170e9ac620042" open CategoryTheory universe u v variable {X : Type u} {Y : Type v} [TopologicalSpace X] [TopologicalSpace Y] variable {x₀ x₁ : X} noncomputable section open unitInterval namespace Path namespace Homotopy section def reflTransSymmAux (x : I × I) : ℝ := if (x.2 : ℝ) ≤ 1 / 2 then x.1 * 2 * x.2 else x.1 * (2 - 2 * x.2) #align path.homotopy.refl_trans_symm_aux Path.Homotopy.reflTransSymmAux @[continuity] theorem continuous_reflTransSymmAux : Continuous reflTransSymmAux := by refine continuous_if_le ?_ ?_ (Continuous.continuousOn ?_) (Continuous.continuousOn ?_) ?_ · continuity · continuity · continuity · continuity intro x hx norm_num [hx, mul_assoc] #align path.homotopy.continuous_refl_trans_symm_aux Path.Homotopy.continuous_reflTransSymmAux
Mathlib/AlgebraicTopology/FundamentalGroupoid/Basic.lean
56
79
theorem reflTransSymmAux_mem_I (x : I × I) : reflTransSymmAux x ∈ I := by
dsimp only [reflTransSymmAux] split_ifs · constructor · apply mul_nonneg · apply mul_nonneg · unit_interval · norm_num · unit_interval · rw [mul_assoc] apply mul_le_one · unit_interval · apply mul_nonneg · norm_num · unit_interval · linarith · constructor · apply mul_nonneg · unit_interval linarith [unitInterval.nonneg x.2, unitInterval.le_one x.2] · apply mul_le_one · unit_interval · linarith [unitInterval.nonneg x.2, unitInterval.le_one x.2] · linarith [unitInterval.nonneg x.2, unitInterval.le_one x.2]
false
import Mathlib.Algebra.CharP.Basic import Mathlib.Algebra.CharP.Algebra import Mathlib.Data.Nat.Prime #align_import algebra.char_p.exp_char from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a" universe u variable (R : Type u) section Semiring variable [Semiring R] class inductive ExpChar (R : Type u) [Semiring R] : ℕ → Prop | zero [CharZero R] : ExpChar R 1 | prime {q : ℕ} (hprime : q.Prime) [hchar : CharP R q] : ExpChar R q #align exp_char ExpChar #align exp_char.prime ExpChar.prime instance expChar_prime (p) [CharP R p] [Fact p.Prime] : ExpChar R p := ExpChar.prime Fact.out instance expChar_zero [CharZero R] : ExpChar R 1 := ExpChar.zero instance (S : Type*) [Semiring S] (p) [ExpChar R p] [ExpChar S p] : ExpChar (R × S) p := by obtain hp | ⟨hp⟩ := ‹ExpChar R p› · have := Prod.charZero_of_left R S; exact .zero obtain _ | _ := ‹ExpChar S p› · exact (Nat.not_prime_one hp).elim · have := Prod.charP R S p; exact .prime hp variable {R} in theorem ExpChar.eq {p q : ℕ} (hp : ExpChar R p) (hq : ExpChar R q) : p = q := by cases' hp with hp _ hp' hp · cases' hq with hq _ hq' hq exacts [rfl, False.elim (Nat.not_prime_zero (CharP.eq R hq (CharP.ofCharZero R) ▸ hq'))] · cases' hq with hq _ hq' hq exacts [False.elim (Nat.not_prime_zero (CharP.eq R hp (CharP.ofCharZero R) ▸ hp')), CharP.eq R hp hq] theorem ExpChar.congr {p : ℕ} (q : ℕ) [hq : ExpChar R q] (h : q = p) : ExpChar R p := h ▸ hq noncomputable def ringExpChar (R : Type*) [NonAssocSemiring R] : ℕ := max (ringChar R) 1 theorem ringExpChar.eq (q : ℕ) [h : ExpChar R q] : ringExpChar R = q := by cases' h with _ _ h _ · haveI := CharP.ofCharZero R rw [ringExpChar, ringChar.eq R 0]; rfl rw [ringExpChar, ringChar.eq R q] exact Nat.max_eq_left h.one_lt.le @[simp] theorem ringExpChar.eq_one (R : Type*) [NonAssocSemiring R] [CharZero R] : ringExpChar R = 1 := by rw [ringExpChar, ringChar.eq_zero, max_eq_right zero_le_one] theorem expChar_one_of_char_zero (q : ℕ) [hp : CharP R 0] [hq : ExpChar R q] : q = 1 := by cases' hq with q hq_one hq_prime hq_hchar · rfl · exact False.elim <| hq_prime.ne_zero <| hq_hchar.eq R hp #align exp_char_one_of_char_zero expChar_one_of_char_zero theorem char_eq_expChar_iff (p q : ℕ) [hp : CharP R p] [hq : ExpChar R q] : p = q ↔ p.Prime := by cases' hq with q hq_one hq_prime hq_hchar · rw [(CharP.eq R hp inferInstance : p = 0)] decide · exact ⟨fun hpq => hpq.symm ▸ hq_prime, fun _ => CharP.eq R hp hq_hchar⟩ #align char_eq_exp_char_iff char_eq_expChar_iff section Nontrivial variable [Nontrivial R] theorem char_zero_of_expChar_one (p : ℕ) [hp : CharP R p] [hq : ExpChar R 1] : p = 0 := by cases hq · exact CharP.eq R hp inferInstance · exact False.elim (CharP.char_ne_one R 1 rfl) #align char_zero_of_exp_char_one char_zero_of_expChar_one -- This could be an instance, but there are no `ExpChar R 1` instances in mathlib. theorem charZero_of_expChar_one' [hq : ExpChar R 1] : CharZero R := by cases hq · assumption · exact False.elim (CharP.char_ne_one R 1 rfl) #align char_zero_of_exp_char_one' charZero_of_expChar_one' theorem expChar_one_iff_char_zero (p q : ℕ) [CharP R p] [ExpChar R q] : q = 1 ↔ p = 0 := by constructor · rintro rfl exact char_zero_of_expChar_one R p · rintro rfl exact expChar_one_of_char_zero R q #align exp_char_one_iff_char_zero expChar_one_iff_char_zero section NoZeroDivisors variable [NoZeroDivisors R]
Mathlib/Algebra/CharP/ExpChar.lean
133
136
theorem char_prime_of_ne_zero {p : ℕ} [hp : CharP R p] (p_ne_zero : p ≠ 0) : Nat.Prime p := by
cases' CharP.char_is_prime_or_zero R p with h h · exact h · contradiction
false
import Mathlib.Algebra.Polynomial.BigOperators import Mathlib.Algebra.Polynomial.Degree.Lemmas import Mathlib.LinearAlgebra.Matrix.Determinant.Basic import Mathlib.Tactic.ComputeDegree #align_import linear_algebra.matrix.polynomial from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a" set_option linter.uppercaseLean3 false open Matrix Polynomial variable {n α : Type*} [DecidableEq n] [Fintype n] [CommRing α] open Polynomial Matrix Equiv.Perm namespace Polynomial theorem natDegree_det_X_add_C_le (A B : Matrix n n α) : natDegree (det ((X : α[X]) • A.map C + B.map C : Matrix n n α[X])) ≤ Fintype.card n := by rw [det_apply] refine (natDegree_sum_le _ _).trans ?_ refine Multiset.max_le_of_forall_le _ _ ?_ simp only [forall_apply_eq_imp_iff, true_and_iff, Function.comp_apply, Multiset.map_map, Multiset.mem_map, exists_imp, Finset.mem_univ_val] intro g calc natDegree (sign g • ∏ i : n, (X • A.map C + B.map C : Matrix n n α[X]) (g i) i) ≤ natDegree (∏ i : n, (X • A.map C + B.map C : Matrix n n α[X]) (g i) i) := by cases' Int.units_eq_one_or (sign g) with sg sg · rw [sg, one_smul] · rw [sg, Units.neg_smul, one_smul, natDegree_neg] _ ≤ ∑ i : n, natDegree (((X : α[X]) • A.map C + B.map C : Matrix n n α[X]) (g i) i) := (natDegree_prod_le (Finset.univ : Finset n) fun i : n => (X • A.map C + B.map C : Matrix n n α[X]) (g i) i) _ ≤ Finset.univ.card • 1 := (Finset.sum_le_card_nsmul _ _ 1 fun (i : n) _ => ?_) _ ≤ Fintype.card n := by simp [mul_one, Algebra.id.smul_eq_mul, Finset.card_univ] dsimp only [add_apply, smul_apply, map_apply, smul_eq_mul] compute_degree #align polynomial.nat_degree_det_X_add_C_le Polynomial.natDegree_det_X_add_C_le theorem coeff_det_X_add_C_zero (A B : Matrix n n α) : coeff (det ((X : α[X]) • A.map C + B.map C)) 0 = det B := by rw [det_apply, finset_sum_coeff, det_apply] refine Finset.sum_congr rfl ?_ rintro g - convert coeff_smul (R := α) (sign g) _ 0 rw [coeff_zero_prod] refine Finset.prod_congr rfl ?_ simp #align polynomial.coeff_det_X_add_C_zero Polynomial.coeff_det_X_add_C_zero theorem coeff_det_X_add_C_card (A B : Matrix n n α) : coeff (det ((X : α[X]) • A.map C + B.map C)) (Fintype.card n) = det A := by rw [det_apply, det_apply, finset_sum_coeff] refine Finset.sum_congr rfl ?_ simp only [Algebra.id.smul_eq_mul, Finset.mem_univ, RingHom.mapMatrix_apply, forall_true_left, map_apply, Pi.smul_apply] intro g convert coeff_smul (R := α) (sign g) _ _ rw [← mul_one (Fintype.card n)] convert (coeff_prod_of_natDegree_le (R := α) _ _ _ _).symm · simp [coeff_C] · rintro p - dsimp only [add_apply, smul_apply, map_apply, smul_eq_mul] compute_degree #align polynomial.coeff_det_X_add_C_card Polynomial.coeff_det_X_add_C_card
Mathlib/LinearAlgebra/Matrix/Polynomial.lean
89
102
theorem leadingCoeff_det_X_one_add_C (A : Matrix n n α) : leadingCoeff (det ((X : α[X]) • (1 : Matrix n n α[X]) + A.map C)) = 1 := by
cases subsingleton_or_nontrivial α · simp [eq_iff_true_of_subsingleton] rw [← @det_one n, ← coeff_det_X_add_C_card _ A, leadingCoeff] simp only [Matrix.map_one, C_eq_zero, RingHom.map_one] rcases (natDegree_det_X_add_C_le 1 A).eq_or_lt with h | h · simp only [RingHom.map_one, Matrix.map_one, C_eq_zero] at h rw [h] · -- contradiction. we have a hypothesis that the degree is less than |n| -- but we know that coeff _ n = 1 have H := coeff_eq_zero_of_natDegree_lt h rw [coeff_det_X_add_C_card] at H simp at H
false
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'
Mathlib/RingTheory/Ideal/Operations.lean
82
96
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]
false
import Mathlib.Topology.Algebra.InfiniteSum.Defs import Mathlib.Data.Fintype.BigOperators import Mathlib.Topology.Algebra.Monoid noncomputable section open Filter Finset Function open scoped Topology variable {α β γ δ : Type*} section HasProd variable [CommMonoid α] [TopologicalSpace α] variable {f g : β → α} {a b : α} {s : Finset β} @[to_additive "Constant zero function has sum `0`"] theorem hasProd_one : HasProd (fun _ ↦ 1 : β → α) 1 := by simp [HasProd, tendsto_const_nhds] #align has_sum_zero hasSum_zero @[to_additive] theorem hasProd_empty [IsEmpty β] : HasProd f 1 := by convert @hasProd_one α β _ _ #align has_sum_empty hasSum_empty @[to_additive] theorem multipliable_one : Multipliable (fun _ ↦ 1 : β → α) := hasProd_one.multipliable #align summable_zero summable_zero @[to_additive] theorem multipliable_empty [IsEmpty β] : Multipliable f := hasProd_empty.multipliable #align summable_empty summable_empty @[to_additive] theorem multipliable_congr (hfg : ∀ b, f b = g b) : Multipliable f ↔ Multipliable g := iff_of_eq (congr_arg Multipliable <| funext hfg) #align summable_congr summable_congr @[to_additive] theorem Multipliable.congr (hf : Multipliable f) (hfg : ∀ b, f b = g b) : Multipliable g := (multipliable_congr hfg).mp hf #align summable.congr Summable.congr @[to_additive] lemma HasProd.congr_fun (hf : HasProd f a) (h : ∀ x : β, g x = f x) : HasProd g a := (funext h : g = f) ▸ hf @[to_additive] theorem HasProd.hasProd_of_prod_eq {g : γ → α} (h_eq : ∀ u : Finset γ, ∃ v : Finset β, ∀ v', v ⊆ v' → ∃ u', u ⊆ u' ∧ ∏ x ∈ u', g x = ∏ b ∈ v', f b) (hf : HasProd g a) : HasProd f a := le_trans (map_atTop_finset_prod_le_of_prod_eq h_eq) hf #align has_sum.has_sum_of_sum_eq HasSum.hasSum_of_sum_eq @[to_additive] theorem hasProd_iff_hasProd {g : γ → α} (h₁ : ∀ u : Finset γ, ∃ v : Finset β, ∀ v', v ⊆ v' → ∃ u', u ⊆ u' ∧ ∏ x ∈ u', g x = ∏ b ∈ v', f b) (h₂ : ∀ v : Finset β, ∃ u : Finset γ, ∀ u', u ⊆ u' → ∃ v', v ⊆ v' ∧ ∏ b ∈ v', f b = ∏ x ∈ u', g x) : HasProd f a ↔ HasProd g a := ⟨HasProd.hasProd_of_prod_eq h₂, HasProd.hasProd_of_prod_eq h₁⟩ #align has_sum_iff_has_sum hasSum_iff_hasSum @[to_additive] theorem Function.Injective.multipliable_iff {g : γ → β} (hg : Injective g) (hf : ∀ x ∉ Set.range g, f x = 1) : Multipliable (f ∘ g) ↔ Multipliable f := exists_congr fun _ ↦ hg.hasProd_iff hf #align function.injective.summable_iff Function.Injective.summable_iff @[to_additive (attr := simp)] theorem hasProd_extend_one {g : β → γ} (hg : Injective g) : HasProd (extend g f 1) a ↔ HasProd f a := by rw [← hg.hasProd_iff, extend_comp hg] exact extend_apply' _ _ @[to_additive (attr := simp)] theorem multipliable_extend_one {g : β → γ} (hg : Injective g) : Multipliable (extend g f 1) ↔ Multipliable f := exists_congr fun _ ↦ hasProd_extend_one hg @[to_additive] theorem hasProd_subtype_iff_mulIndicator {s : Set β} : HasProd (f ∘ (↑) : s → α) a ↔ HasProd (s.mulIndicator f) a := by rw [← Set.mulIndicator_range_comp, Subtype.range_coe, hasProd_subtype_iff_of_mulSupport_subset Set.mulSupport_mulIndicator_subset] #align has_sum_subtype_iff_indicator hasSum_subtype_iff_indicator @[to_additive] theorem multipliable_subtype_iff_mulIndicator {s : Set β} : Multipliable (f ∘ (↑) : s → α) ↔ Multipliable (s.mulIndicator f) := exists_congr fun _ ↦ hasProd_subtype_iff_mulIndicator #align summable_subtype_iff_indicator summable_subtype_iff_indicator @[to_additive (attr := simp)] theorem hasProd_subtype_mulSupport : HasProd (f ∘ (↑) : mulSupport f → α) a ↔ HasProd f a := hasProd_subtype_iff_of_mulSupport_subset <| Set.Subset.refl _ #align has_sum_subtype_support hasSum_subtype_support @[to_additive] protected theorem Finset.multipliable (s : Finset β) (f : β → α) : Multipliable (f ∘ (↑) : (↑s : Set β) → α) := (s.hasProd f).multipliable #align finset.summable Finset.summable @[to_additive] protected theorem Set.Finite.multipliable {s : Set β} (hs : s.Finite) (f : β → α) : Multipliable (f ∘ (↑) : s → α) := by have := hs.toFinset.multipliable f rwa [hs.coe_toFinset] at this #align set.finite.summable Set.Finite.summable @[to_additive]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
132
133
theorem multipliable_of_finite_mulSupport (h : (mulSupport f).Finite) : Multipliable f := by
apply multipliable_of_ne_finset_one (s := h.toFinset); simp
false
import Mathlib.LinearAlgebra.Prod #align_import linear_algebra.linear_pmap from "leanprover-community/mathlib"@"8b981918a93bc45a8600de608cde7944a80d92b9" universe u v w structure LinearPMap (R : Type u) [Ring R] (E : Type v) [AddCommGroup E] [Module R E] (F : Type w) [AddCommGroup F] [Module R F] where domain : Submodule R E toFun : domain →ₗ[R] F #align linear_pmap LinearPMap @[inherit_doc] notation:25 E " →ₗ.[" R:25 "] " F:0 => LinearPMap R E F variable {R : Type*} [Ring R] {E : Type*} [AddCommGroup E] [Module R E] {F : Type*} [AddCommGroup F] [Module R F] {G : Type*} [AddCommGroup G] [Module R G] namespace LinearPMap open Submodule -- Porting note: A new definition underlying a coercion `↑`. @[coe] def toFun' (f : E →ₗ.[R] F) : f.domain → F := f.toFun instance : CoeFun (E →ₗ.[R] F) fun f : E →ₗ.[R] F => f.domain → F := ⟨toFun'⟩ @[simp] theorem toFun_eq_coe (f : E →ₗ.[R] F) (x : f.domain) : f.toFun x = f x := rfl #align linear_pmap.to_fun_eq_coe LinearPMap.toFun_eq_coe @[ext]
Mathlib/LinearAlgebra/LinearPMap.lean
64
70
theorem ext {f g : E →ₗ.[R] F} (h : f.domain = g.domain) (h' : ∀ ⦃x : f.domain⦄ ⦃y : g.domain⦄ (_h : (x : E) = y), f x = g y) : f = g := by
rcases f with ⟨f_dom, f⟩ rcases g with ⟨g_dom, g⟩ obtain rfl : f_dom = g_dom := h obtain rfl : f = g := LinearMap.ext fun x => h' rfl rfl
false
import Mathlib.Analysis.Convex.Slope import Mathlib.Analysis.SpecialFunctions.Pow.Real import Mathlib.Tactic.LinearCombination #align_import analysis.convex.specific_functions.basic from "leanprover-community/mathlib"@"8f9fea08977f7e450770933ee6abb20733b47c92" open Real Set NNReal theorem strictConvexOn_exp : StrictConvexOn ℝ univ exp := by apply strictConvexOn_of_slope_strict_mono_adjacent convex_univ rintro x y z - - hxy hyz trans exp y · have h1 : 0 < y - x := by linarith have h2 : x - y < 0 := by linarith rw [div_lt_iff h1] calc exp y - exp x = exp y - exp y * exp (x - y) := by rw [← exp_add]; ring_nf _ = exp y * (1 - exp (x - y)) := by ring _ < exp y * -(x - y) := by gcongr; linarith [add_one_lt_exp h2.ne] _ = exp y * (y - x) := by ring · have h1 : 0 < z - y := by linarith rw [lt_div_iff h1] calc exp y * (z - y) < exp y * (exp (z - y) - 1) := by gcongr _ * ?_ linarith [add_one_lt_exp h1.ne'] _ = exp (z - y) * exp y - exp y := by ring _ ≤ exp z - exp y := by rw [← exp_add]; ring_nf; rfl #align strict_convex_on_exp strictConvexOn_exp theorem convexOn_exp : ConvexOn ℝ univ exp := strictConvexOn_exp.convexOn #align convex_on_exp convexOn_exp theorem strictConcaveOn_log_Ioi : StrictConcaveOn ℝ (Ioi 0) log := by apply strictConcaveOn_of_slope_strict_anti_adjacent (convex_Ioi (0 : ℝ)) intro x y z (hx : 0 < x) (hz : 0 < z) hxy hyz have hy : 0 < y := hx.trans hxy trans y⁻¹ · have h : 0 < z - y := by linarith rw [div_lt_iff h] have hyz' : 0 < z / y := by positivity have hyz'' : z / y ≠ 1 := by contrapose! h rw [div_eq_one_iff_eq hy.ne'] at h simp [h] calc log z - log y = log (z / y) := by rw [← log_div hz.ne' hy.ne'] _ < z / y - 1 := log_lt_sub_one_of_pos hyz' hyz'' _ = y⁻¹ * (z - y) := by field_simp · have h : 0 < y - x := by linarith rw [lt_div_iff h] have hxy' : 0 < x / y := by positivity have hxy'' : x / y ≠ 1 := by contrapose! h rw [div_eq_one_iff_eq hy.ne'] at h simp [h] calc y⁻¹ * (y - x) = 1 - x / y := by field_simp _ < -log (x / y) := by linarith [log_lt_sub_one_of_pos hxy' hxy''] _ = -(log x - log y) := by rw [log_div hx.ne' hy.ne'] _ = log y - log x := by ring #align strict_concave_on_log_Ioi strictConcaveOn_log_Ioi theorem one_add_mul_self_lt_rpow_one_add {s : ℝ} (hs : -1 ≤ s) (hs' : s ≠ 0) {p : ℝ} (hp : 1 < p) : 1 + p * s < (1 + s) ^ p := by have hp' : 0 < p := zero_lt_one.trans hp rcases eq_or_lt_of_le hs with rfl | hs · rwa [add_right_neg, zero_rpow hp'.ne', mul_neg_one, add_neg_lt_iff_lt_add, zero_add] have hs1 : 0 < 1 + s := neg_lt_iff_pos_add'.mp hs rcases le_or_lt (1 + p * s) 0 with hs2 | hs2 · exact hs2.trans_lt (rpow_pos_of_pos hs1 _) have hs3 : 1 + s ≠ 1 := hs' ∘ add_right_eq_self.mp have hs4 : 1 + p * s ≠ 1 := by contrapose! hs'; rwa [add_right_eq_self, mul_eq_zero, eq_false_intro hp'.ne', false_or] at hs' rw [rpow_def_of_pos hs1, ← exp_log hs2] apply exp_strictMono cases' lt_or_gt_of_ne hs' with hs' hs' · rw [← div_lt_iff hp', ← div_lt_div_right_of_neg hs'] convert strictConcaveOn_log_Ioi.secant_strict_mono (zero_lt_one' ℝ) hs2 hs1 hs4 hs3 _ using 1 · rw [add_sub_cancel_left, log_one, sub_zero] · rw [add_sub_cancel_left, div_div, log_one, sub_zero] · apply add_lt_add_left (mul_lt_of_one_lt_left hs' hp) · rw [← div_lt_iff hp', ← div_lt_div_right hs'] convert strictConcaveOn_log_Ioi.secant_strict_mono (zero_lt_one' ℝ) hs1 hs2 hs3 hs4 _ using 1 · rw [add_sub_cancel_left, div_div, log_one, sub_zero] · rw [add_sub_cancel_left, log_one, sub_zero] · apply add_lt_add_left (lt_mul_of_one_lt_left hs' hp) #align one_add_mul_self_lt_rpow_one_add one_add_mul_self_lt_rpow_one_add theorem one_add_mul_self_le_rpow_one_add {s : ℝ} (hs : -1 ≤ s) {p : ℝ} (hp : 1 ≤ p) : 1 + p * s ≤ (1 + s) ^ p := by rcases eq_or_lt_of_le hp with (rfl | hp) · simp by_cases hs' : s = 0 · simp [hs'] exact (one_add_mul_self_lt_rpow_one_add hs hs' hp).le #align one_add_mul_self_le_rpow_one_add one_add_mul_self_le_rpow_one_add
Mathlib/Analysis/Convex/SpecificFunctions/Basic.lean
138
163
theorem rpow_one_add_lt_one_add_mul_self {s : ℝ} (hs : -1 ≤ s) (hs' : s ≠ 0) {p : ℝ} (hp1 : 0 < p) (hp2 : p < 1) : (1 + s) ^ p < 1 + p * s := by
rcases eq_or_lt_of_le hs with rfl | hs · rwa [add_right_neg, zero_rpow hp1.ne', mul_neg_one, lt_add_neg_iff_add_lt, zero_add] have hs1 : 0 < 1 + s := neg_lt_iff_pos_add'.mp hs have hs2 : 0 < 1 + p * s := by rw [← neg_lt_iff_pos_add'] rcases lt_or_gt_of_ne hs' with h | h · exact hs.trans (lt_mul_of_lt_one_left h hp2) · exact neg_one_lt_zero.trans (mul_pos hp1 h) have hs3 : 1 + s ≠ 1 := hs' ∘ add_right_eq_self.mp have hs4 : 1 + p * s ≠ 1 := by contrapose! hs'; rwa [add_right_eq_self, mul_eq_zero, eq_false_intro hp1.ne', false_or] at hs' rw [rpow_def_of_pos hs1, ← exp_log hs2] apply exp_strictMono cases' lt_or_gt_of_ne hs' with hs' hs' · rw [← lt_div_iff hp1, ← div_lt_div_right_of_neg hs'] convert strictConcaveOn_log_Ioi.secant_strict_mono (zero_lt_one' ℝ) hs1 hs2 hs3 hs4 _ using 1 · rw [add_sub_cancel_left, div_div, log_one, sub_zero] · rw [add_sub_cancel_left, log_one, sub_zero] · apply add_lt_add_left (lt_mul_of_lt_one_left hs' hp2) · rw [← lt_div_iff hp1, ← div_lt_div_right hs'] convert strictConcaveOn_log_Ioi.secant_strict_mono (zero_lt_one' ℝ) hs2 hs1 hs4 hs3 _ using 1 · rw [add_sub_cancel_left, log_one, sub_zero] · rw [add_sub_cancel_left, div_div, log_one, sub_zero] · apply add_lt_add_left (mul_lt_of_lt_one_left hs' hp2)
false
import Mathlib.Algebra.CharP.Defs import Mathlib.RingTheory.Multiplicity import Mathlib.RingTheory.PowerSeries.Basic #align_import ring_theory.power_series.basic from "leanprover-community/mathlib"@"2d5739b61641ee4e7e53eca5688a08f66f2e6a60" noncomputable section open Polynomial open Finset (antidiagonal mem_antidiagonal) namespace PowerSeries open Finsupp (single) variable {R : Type*} section OrderBasic open multiplicity variable [Semiring R] {φ : R⟦X⟧}
Mathlib/RingTheory/PowerSeries/Order.lean
47
51
theorem exists_coeff_ne_zero_iff_ne_zero : (∃ n : ℕ, coeff R n φ ≠ 0) ↔ φ ≠ 0 := by
refine not_iff_not.mp ?_ push_neg -- FIXME: the `FunLike.coe` doesn't seem to be picked up in the expression after #8386? simp [PowerSeries.ext_iff, (coeff R _).map_zero]
false
import Mathlib.Algebra.Group.Equiv.TypeTags import Mathlib.Data.ZMod.Quotient import Mathlib.RingTheory.DedekindDomain.AdicValuation #align_import ring_theory.dedekind_domain.selmer_group from "leanprover-community/mathlib"@"2032a878972d5672e7c27c957e7a6e297b044973" set_option quotPrecheck false local notation K "/" n => Kˣ ⧸ (powMonoidHom n : Kˣ →* Kˣ).range namespace IsDedekindDomain noncomputable section open scoped Classical DiscreteValuation nonZeroDivisors universe u v variable {R : Type u} [CommRing R] [IsDedekindDomain R] {K : Type v} [Field K] [Algebra R K] [IsFractionRing R K] (v : HeightOneSpectrum R) namespace HeightOneSpectrum def valuationOfNeZeroToFun (x : Kˣ) : Multiplicative ℤ := let hx := IsLocalization.sec R⁰ (x : K) Multiplicative.ofAdd <| (-(Associates.mk v.asIdeal).count (Associates.mk <| Ideal.span {hx.fst}).factors : ℤ) - (-(Associates.mk v.asIdeal).count (Associates.mk <| Ideal.span {(hx.snd : R)}).factors : ℤ) #align is_dedekind_domain.height_one_spectrum.valuation_of_ne_zero_to_fun IsDedekindDomain.HeightOneSpectrum.valuationOfNeZeroToFun @[simp] theorem valuationOfNeZeroToFun_eq (x : Kˣ) : (v.valuationOfNeZeroToFun x : ℤₘ₀) = v.valuation (x : K) := by rw [show v.valuation (x : K) = _ * _ by rfl] rw [Units.val_inv_eq_inv_val] change _ = ite _ _ _ * (ite _ _ _)⁻¹ simp_rw [IsLocalization.toLocalizationMap_sec, SubmonoidClass.coe_subtype, if_neg <| IsLocalization.sec_fst_ne_zero le_rfl x.ne_zero, if_neg (nonZeroDivisors.coe_ne_zero _), valuationOfNeZeroToFun, ofAdd_sub, ofAdd_neg, div_inv_eq_mul, WithZero.coe_mul, WithZero.coe_inv, inv_inv] #align is_dedekind_domain.height_one_spectrum.valuation_of_ne_zero_to_fun_eq IsDedekindDomain.HeightOneSpectrum.valuationOfNeZeroToFun_eq def valuationOfNeZero : Kˣ →* Multiplicative ℤ where toFun := v.valuationOfNeZeroToFun map_one' := by rw [← WithZero.coe_inj, valuationOfNeZeroToFun_eq]; exact map_one _ map_mul' _ _ := by rw [← WithZero.coe_inj, WithZero.coe_mul] simp only [valuationOfNeZeroToFun_eq]; exact map_mul _ _ _ #align is_dedekind_domain.height_one_spectrum.valuation_of_ne_zero IsDedekindDomain.HeightOneSpectrum.valuationOfNeZero @[simp] theorem valuationOfNeZero_eq (x : Kˣ) : (v.valuationOfNeZero x : ℤₘ₀) = v.valuation (x : K) := valuationOfNeZeroToFun_eq v x #align is_dedekind_domain.height_one_spectrum.valuation_of_ne_zero_eq IsDedekindDomain.HeightOneSpectrum.valuationOfNeZero_eq @[simp] theorem valuation_of_unit_eq (x : Rˣ) : v.valuationOfNeZero (Units.map (algebraMap R K : R →* K) x) = 1 := by rw [← WithZero.coe_inj, valuationOfNeZero_eq, Units.coe_map, eq_iff_le_not_lt] constructor · exact v.valuation_le_one x · cases' x with x _ hx _ change ¬v.valuation (algebraMap R K x) < 1 apply_fun v.intValuation at hx rw [map_one, map_mul] at hx rw [not_lt, ← hx, ← mul_one <| v.valuation _, valuation_of_algebraMap, mul_le_mul_left₀ <| left_ne_zero_of_mul_eq_one hx] exact v.int_valuation_le_one _ #align is_dedekind_domain.height_one_spectrum.valuation_of_unit_eq IsDedekindDomain.HeightOneSpectrum.valuation_of_unit_eq -- Porting note: invalid attribute 'semireducible', declaration is in an imported module -- attribute [local semireducible] MulOpposite def valuationOfNeZeroMod (n : ℕ) : (K/n) →* Multiplicative (ZMod n) := (Int.quotientZMultiplesNatEquivZMod n).toMultiplicative.toMonoidHom.comp <| QuotientGroup.map (powMonoidHom n : Kˣ →* Kˣ).range (AddSubgroup.toSubgroup (AddSubgroup.zmultiples (n : ℤ))) v.valuationOfNeZero (by rintro _ ⟨x, rfl⟩ exact ⟨v.valuationOfNeZero x, by simp only [powMonoidHom_apply, map_pow, Int.toAdd_pow]; rfl⟩) #align is_dedekind_domain.height_one_spectrum.valuation_of_ne_zero_mod IsDedekindDomain.HeightOneSpectrum.valuationOfNeZeroMod @[simp]
Mathlib/RingTheory/DedekindDomain/SelmerGroup.lean
150
155
theorem valuation_of_unit_mod_eq (n : ℕ) (x : Rˣ) : v.valuationOfNeZeroMod n (Units.map (algebraMap R K : R →* K) x : K/n) = 1 := by
-- This used to be `rw`, but we need `erw` after leanprover/lean4#2644 erw [valuationOfNeZeroMod, MonoidHom.comp_apply, ← QuotientGroup.coe_mk', QuotientGroup.map_mk' (G := Kˣ) (N := MonoidHom.range (powMonoidHom n)), valuation_of_unit_eq, QuotientGroup.mk_one, map_one]
false
import Mathlib.Algebra.BigOperators.Fin import Mathlib.Algebra.BigOperators.NatAntidiagonal import Mathlib.Algebra.CharZero.Lemmas import Mathlib.Data.Finset.NatAntidiagonal import Mathlib.Data.Nat.Choose.Central import Mathlib.Data.Tree.Basic import Mathlib.Tactic.FieldSimp import Mathlib.Tactic.GCongr import Mathlib.Tactic.Positivity #align_import combinatorics.catalan from "leanprover-community/mathlib"@"26b40791e4a5772a4e53d0e28e4df092119dc7da" open Finset open Finset.antidiagonal (fst_le snd_le) def catalan : ℕ → ℕ | 0 => 1 | n + 1 => ∑ i : Fin n.succ, catalan i * catalan (n - i) #align catalan catalan @[simp] theorem catalan_zero : catalan 0 = 1 := by rw [catalan] #align catalan_zero catalan_zero theorem catalan_succ (n : ℕ) : catalan (n + 1) = ∑ i : Fin n.succ, catalan i * catalan (n - i) := by rw [catalan] #align catalan_succ catalan_succ theorem catalan_succ' (n : ℕ) : catalan (n + 1) = ∑ ij ∈ antidiagonal n, catalan ij.1 * catalan ij.2 := by rw [catalan_succ, Nat.sum_antidiagonal_eq_sum_range_succ (fun x y => catalan x * catalan y) n, sum_range] #align catalan_succ' catalan_succ' @[simp] theorem catalan_one : catalan 1 = 1 := by simp [catalan_succ] #align catalan_one catalan_one private def gosperCatalan (n j : ℕ) : ℚ := Nat.centralBinom j * Nat.centralBinom (n - j) * (2 * j - n) / (2 * n * (n + 1)) private theorem gosper_trick {n i : ℕ} (h : i ≤ n) : gosperCatalan (n + 1) (i + 1) - gosperCatalan (n + 1) i = Nat.centralBinom i / (i + 1) * Nat.centralBinom (n - i) / (n - i + 1) := by have l₁ : (i : ℚ) + 1 ≠ 0 := by norm_cast have l₂ : (n : ℚ) - i + 1 ≠ 0 := by norm_cast have h₁ := (mul_div_cancel_left₀ (↑(Nat.centralBinom (i + 1))) l₁).symm have h₂ := (mul_div_cancel_left₀ (↑(Nat.centralBinom (n - i + 1))) l₂).symm have h₃ : ((i : ℚ) + 1) * (i + 1).centralBinom = 2 * (2 * i + 1) * i.centralBinom := mod_cast Nat.succ_mul_centralBinom_succ i have h₄ : ((n : ℚ) - i + 1) * (n - i + 1).centralBinom = 2 * (2 * (n - i) + 1) * (n - i).centralBinom := mod_cast Nat.succ_mul_centralBinom_succ (n - i) simp only [gosperCatalan] push_cast rw [show n + 1 - i = n - i + 1 by rw [Nat.add_comm (n - i) 1, ← (Nat.add_sub_assoc h 1), add_comm]] rw [h₁, h₂, h₃, h₄] field_simp ring private theorem gosper_catalan_sub_eq_central_binom_div (n : ℕ) : gosperCatalan (n + 1) (n + 1) - gosperCatalan (n + 1) 0 = Nat.centralBinom (n + 1) / (n + 2) := by have : (n : ℚ) + 1 ≠ 0 := by norm_cast have : (n : ℚ) + 1 + 1 ≠ 0 := by norm_cast have h : (n : ℚ) + 2 ≠ 0 := by norm_cast simp only [gosperCatalan, Nat.sub_zero, Nat.centralBinom_zero, Nat.sub_self] field_simp ring
Mathlib/Combinatorics/Enumerative/Catalan.lean
116
137
theorem catalan_eq_centralBinom_div (n : ℕ) : catalan n = n.centralBinom / (n + 1) := by
suffices (catalan n : ℚ) = Nat.centralBinom n / (n + 1) by have h := Nat.succ_dvd_centralBinom n exact mod_cast this induction' n using Nat.case_strong_induction_on with d hd · simp · simp_rw [catalan_succ, Nat.cast_sum, Nat.cast_mul] trans (∑ i : Fin d.succ, Nat.centralBinom i / (i + 1) * (Nat.centralBinom (d - i) / (d - i + 1)) : ℚ) · congr ext1 x have m_le_d : x.val ≤ d := by apply Nat.le_of_lt_succ; apply x.2 have d_minus_x_le_d : (d - x.val) ≤ d := tsub_le_self rw [hd _ m_le_d, hd _ d_minus_x_le_d] norm_cast · trans (∑ i : Fin d.succ, (gosperCatalan (d + 1) (i + 1) - gosperCatalan (d + 1) i)) · refine sum_congr rfl fun i _ => ?_ rw [gosper_trick i.is_le, mul_div] · rw [← sum_range fun i => gosperCatalan (d + 1) (i + 1) - gosperCatalan (d + 1) i, sum_range_sub, Nat.succ_eq_add_one] rw [gosper_catalan_sub_eq_central_binom_div d] norm_cast
false
import Mathlib.Data.Set.Image import Mathlib.Order.SuccPred.Relation import Mathlib.Topology.Clopen import Mathlib.Topology.Irreducible #align_import topology.connected from "leanprover-community/mathlib"@"d101e93197bb5f6ea89bd7ba386b7f7dff1f3903" open Set Function Topology TopologicalSpace Relation open scoped Classical universe u v variable {α : Type u} {β : Type v} {ι : Type*} {π : ι → Type*} [TopologicalSpace α] {s t u v : Set α} section Preconnected def IsPreconnected (s : Set α) : Prop := ∀ u v : Set α, IsOpen u → IsOpen v → s ⊆ u ∪ v → (s ∩ u).Nonempty → (s ∩ v).Nonempty → (s ∩ (u ∩ v)).Nonempty #align is_preconnected IsPreconnected def IsConnected (s : Set α) : Prop := s.Nonempty ∧ IsPreconnected s #align is_connected IsConnected theorem IsConnected.nonempty {s : Set α} (h : IsConnected s) : s.Nonempty := h.1 #align is_connected.nonempty IsConnected.nonempty theorem IsConnected.isPreconnected {s : Set α} (h : IsConnected s) : IsPreconnected s := h.2 #align is_connected.is_preconnected IsConnected.isPreconnected theorem IsPreirreducible.isPreconnected {s : Set α} (H : IsPreirreducible s) : IsPreconnected s := fun _ _ hu hv _ => H _ _ hu hv #align is_preirreducible.is_preconnected IsPreirreducible.isPreconnected theorem IsIrreducible.isConnected {s : Set α} (H : IsIrreducible s) : IsConnected s := ⟨H.nonempty, H.isPreirreducible.isPreconnected⟩ #align is_irreducible.is_connected IsIrreducible.isConnected theorem isPreconnected_empty : IsPreconnected (∅ : Set α) := isPreirreducible_empty.isPreconnected #align is_preconnected_empty isPreconnected_empty theorem isConnected_singleton {x} : IsConnected ({x} : Set α) := isIrreducible_singleton.isConnected #align is_connected_singleton isConnected_singleton theorem isPreconnected_singleton {x} : IsPreconnected ({x} : Set α) := isConnected_singleton.isPreconnected #align is_preconnected_singleton isPreconnected_singleton theorem Set.Subsingleton.isPreconnected {s : Set α} (hs : s.Subsingleton) : IsPreconnected s := hs.induction_on isPreconnected_empty fun _ => isPreconnected_singleton #align set.subsingleton.is_preconnected Set.Subsingleton.isPreconnected theorem isPreconnected_of_forall {s : Set α} (x : α) (H : ∀ y ∈ s, ∃ t, t ⊆ s ∧ x ∈ t ∧ y ∈ t ∧ IsPreconnected t) : IsPreconnected s := by rintro u v hu hv hs ⟨z, zs, zu⟩ ⟨y, ys, yv⟩ have xs : x ∈ s := by rcases H y ys with ⟨t, ts, xt, -, -⟩ exact ts xt -- Porting note (#11215): TODO: use `wlog xu : x ∈ u := hs xs using u v y z, v u z y` cases hs xs with | inl xu => rcases H y ys with ⟨t, ts, xt, yt, ht⟩ have := ht u v hu hv (ts.trans hs) ⟨x, xt, xu⟩ ⟨y, yt, yv⟩ exact this.imp fun z hz => ⟨ts hz.1, hz.2⟩ | inr xv => rcases H z zs with ⟨t, ts, xt, zt, ht⟩ have := ht v u hv hu (ts.trans <| by rwa [union_comm]) ⟨x, xt, xv⟩ ⟨z, zt, zu⟩ exact this.imp fun _ h => ⟨ts h.1, h.2.2, h.2.1⟩ #align is_preconnected_of_forall isPreconnected_of_forall theorem isPreconnected_of_forall_pair {s : Set α} (H : ∀ x ∈ s, ∀ y ∈ s, ∃ t, t ⊆ s ∧ x ∈ t ∧ y ∈ t ∧ IsPreconnected t) : IsPreconnected s := by rcases eq_empty_or_nonempty s with (rfl | ⟨x, hx⟩) exacts [isPreconnected_empty, isPreconnected_of_forall x fun y => H x hx y] #align is_preconnected_of_forall_pair isPreconnected_of_forall_pair theorem isPreconnected_sUnion (x : α) (c : Set (Set α)) (H1 : ∀ s ∈ c, x ∈ s) (H2 : ∀ s ∈ c, IsPreconnected s) : IsPreconnected (⋃₀ c) := by apply isPreconnected_of_forall x rintro y ⟨s, sc, ys⟩ exact ⟨s, subset_sUnion_of_mem sc, H1 s sc, ys, H2 s sc⟩ #align is_preconnected_sUnion isPreconnected_sUnion theorem isPreconnected_iUnion {ι : Sort*} {s : ι → Set α} (h₁ : (⋂ i, s i).Nonempty) (h₂ : ∀ i, IsPreconnected (s i)) : IsPreconnected (⋃ i, s i) := Exists.elim h₁ fun f hf => isPreconnected_sUnion f _ hf (forall_mem_range.2 h₂) #align is_preconnected_Union isPreconnected_iUnion theorem IsPreconnected.union (x : α) {s t : Set α} (H1 : x ∈ s) (H2 : x ∈ t) (H3 : IsPreconnected s) (H4 : IsPreconnected t) : IsPreconnected (s ∪ t) := sUnion_pair s t ▸ isPreconnected_sUnion x {s, t} (by rintro r (rfl | rfl | h) <;> assumption) (by rintro r (rfl | rfl | h) <;> assumption) #align is_preconnected.union IsPreconnected.union theorem IsPreconnected.union' {s t : Set α} (H : (s ∩ t).Nonempty) (hs : IsPreconnected s) (ht : IsPreconnected t) : IsPreconnected (s ∪ t) := by rcases H with ⟨x, hxs, hxt⟩ exact hs.union x hxs hxt ht #align is_preconnected.union' IsPreconnected.union'
Mathlib/Topology/Connected/Basic.lean
148
153
theorem IsConnected.union {s t : Set α} (H : (s ∩ t).Nonempty) (Hs : IsConnected s) (Ht : IsConnected t) : IsConnected (s ∪ t) := by
rcases H with ⟨x, hx⟩ refine ⟨⟨x, mem_union_left t (mem_of_mem_inter_left hx)⟩, ?_⟩ exact Hs.isPreconnected.union x (mem_of_mem_inter_left hx) (mem_of_mem_inter_right hx) Ht.isPreconnected
false
import Mathlib.Algebra.Homology.Homotopy import Mathlib.Algebra.Category.ModuleCat.Abelian import Mathlib.Algebra.Category.ModuleCat.Subobject import Mathlib.CategoryTheory.Limits.Shapes.ConcreteCategory #align_import algebra.homology.Module from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a" universe v u open scoped Classical noncomputable section open CategoryTheory Limits HomologicalComplex variable {R : Type v} [Ring R] variable {ι : Type*} {c : ComplexShape ι} {C D : HomologicalComplex (ModuleCat.{u} R) c} namespace ModuleCat
Mathlib/Algebra/Homology/ModuleCat.lean
37
49
theorem homology'_ext {L M N K : ModuleCat.{u} R} {f : L ⟶ M} {g : M ⟶ N} (w : f ≫ g = 0) {h k : homology' f g w ⟶ K} (w : ∀ x : LinearMap.ker g, h (cokernel.π (imageToKernel _ _ w) (toKernelSubobject x)) = k (cokernel.π (imageToKernel _ _ w) (toKernelSubobject x))) : h = k := by
refine Concrete.cokernel_funext fun n => ?_ -- Porting note: as `equiv_rw` was not ported, it was replaced by `Equiv.surjective` -- Gosh it would be nice if `equiv_rw` could directly use an isomorphism, or an enriched `≃`. obtain ⟨n, rfl⟩ := (kernelSubobjectIso g ≪≫ ModuleCat.kernelIsoKer g).toLinearEquiv.toEquiv.symm.surjective n exact w n
false
import Mathlib.LinearAlgebra.Dimension.Free import Mathlib.Algebra.Module.Torsion #align_import linear_algebra.dimension from "leanprover-community/mathlib"@"47a5f8186becdbc826190ced4312f8199f9db6a5" noncomputable section universe u v v' u₁' w w' variable {R S : Type u} {M : Type v} {M' : Type v'} {M₁ : Type v} variable {ι : Type w} {ι' : Type w'} {η : Type u₁'} {φ : η → Type*} open Cardinal Basis Submodule Function Set FiniteDimensional DirectSum variable [Ring R] [CommRing S] [AddCommGroup M] [AddCommGroup M'] [AddCommGroup M₁] variable [Module R M] [Module R M'] [Module R M₁] section Finsupp variable (R M M') variable [StrongRankCondition R] [Module.Free R M] [Module.Free R M'] open Module.Free @[simp] theorem rank_finsupp (ι : Type w) : Module.rank R (ι →₀ M) = Cardinal.lift.{v} #ι * Cardinal.lift.{w} (Module.rank R M) := by obtain ⟨⟨_, bs⟩⟩ := Module.Free.exists_basis (R := R) (M := M) rw [← bs.mk_eq_rank'', ← (Finsupp.basis fun _ : ι => bs).mk_eq_rank'', Cardinal.mk_sigma, Cardinal.sum_const] #align rank_finsupp rank_finsupp theorem rank_finsupp' (ι : Type v) : Module.rank R (ι →₀ M) = #ι * Module.rank R M := by simp [rank_finsupp] #align rank_finsupp' rank_finsupp' -- Porting note, this should not be `@[simp]`, as simp can prove it. -- @[simp] theorem rank_finsupp_self (ι : Type w) : Module.rank R (ι →₀ R) = Cardinal.lift.{u} #ι := by simp [rank_finsupp] #align rank_finsupp_self rank_finsupp_self theorem rank_finsupp_self' {ι : Type u} : Module.rank R (ι →₀ R) = #ι := by simp #align rank_finsupp_self' rank_finsupp_self' @[simp] theorem rank_directSum {ι : Type v} (M : ι → Type w) [∀ i : ι, AddCommGroup (M i)] [∀ i : ι, Module R (M i)] [∀ i : ι, Module.Free R (M i)] : Module.rank R (⨁ i, M i) = Cardinal.sum fun i => Module.rank R (M i) := by let B i := chooseBasis R (M i) let b : Basis _ R (⨁ i, M i) := DFinsupp.basis fun i => B i simp [← b.mk_eq_rank'', fun i => (B i).mk_eq_rank''] #align rank_direct_sum rank_directSum @[simp] theorem rank_matrix (m : Type v) (n : Type w) [Finite m] [Finite n] : Module.rank R (Matrix m n R) = Cardinal.lift.{max v w u, v} #m * Cardinal.lift.{max v w u, w} #n := by cases nonempty_fintype m cases nonempty_fintype n have h := (Matrix.stdBasis R m n).mk_eq_rank rw [← lift_lift.{max v w u, max v w}, lift_inj] at h simpa using h.symm #align rank_matrix rank_matrix @[simp high] theorem rank_matrix' (m n : Type v) [Finite m] [Finite n] : Module.rank R (Matrix m n R) = Cardinal.lift.{u} (#m * #n) := by rw [rank_matrix, lift_mul, lift_umax.{v, u}] #align rank_matrix' rank_matrix' -- @[simp] -- Porting note (#10618): simp can prove this theorem rank_matrix'' (m n : Type u) [Finite m] [Finite n] : Module.rank R (Matrix m n R) = #m * #n := by simp #align rank_matrix'' rank_matrix'' variable [Module.Finite R M] [Module.Finite R M'] open Fintype namespace FiniteDimensional @[simp] theorem finrank_finsupp {ι : Type v} [Fintype ι] : finrank R (ι →₀ M) = card ι * finrank R M := by rw [finrank, finrank, rank_finsupp, ← mk_toNat_eq_card, toNat_mul, toNat_lift, toNat_lift] @[simp]
Mathlib/LinearAlgebra/Dimension/Constructions.lean
235
236
theorem finrank_finsupp_self {ι : Type v} [Fintype ι] : finrank R (ι →₀ R) = card ι := by
rw [finrank, rank_finsupp_self, ← mk_toNat_eq_card, toNat_lift]
false
import Mathlib.AlgebraicGeometry.Restrict import Mathlib.CategoryTheory.Adjunction.Limits import Mathlib.CategoryTheory.Adjunction.Reflective #align_import algebraic_geometry.Gamma_Spec_adjunction from "leanprover-community/mathlib"@"d39590fc8728fbf6743249802486f8c91ffe07bc" -- Explicit universe annotations were used in this file to improve perfomance #12737 set_option linter.uppercaseLean3 false noncomputable section universe u open PrimeSpectrum namespace AlgebraicGeometry open Opposite open CategoryTheory open StructureSheaf open Spec (structureSheaf) open TopologicalSpace open AlgebraicGeometry.LocallyRingedSpace open TopCat.Presheaf open TopCat.Presheaf.SheafCondition namespace LocallyRingedSpace variable (X : LocallyRingedSpace.{u}) def ΓToStalk (x : X) : Γ.obj (op X) ⟶ X.presheaf.stalk x := X.presheaf.germ (⟨x, trivial⟩ : (⊤ : Opens X)) #align algebraic_geometry.LocallyRingedSpace.Γ_to_stalk AlgebraicGeometry.LocallyRingedSpace.ΓToStalk def toΓSpecFun : X → PrimeSpectrum (Γ.obj (op X)) := fun x => comap (X.ΓToStalk x) (LocalRing.closedPoint (X.presheaf.stalk x)) #align algebraic_geometry.LocallyRingedSpace.to_Γ_Spec_fun AlgebraicGeometry.LocallyRingedSpace.toΓSpecFun theorem not_mem_prime_iff_unit_in_stalk (r : Γ.obj (op X)) (x : X) : r ∉ (X.toΓSpecFun x).asIdeal ↔ IsUnit (X.ΓToStalk x r) := by erw [LocalRing.mem_maximalIdeal, Classical.not_not] #align algebraic_geometry.LocallyRingedSpace.not_mem_prime_iff_unit_in_stalk AlgebraicGeometry.LocallyRingedSpace.not_mem_prime_iff_unit_in_stalk theorem toΓSpec_preim_basicOpen_eq (r : Γ.obj (op X)) : X.toΓSpecFun ⁻¹' (basicOpen r).1 = (X.toRingedSpace.basicOpen r).1 := by ext erw [X.toRingedSpace.mem_top_basicOpen]; apply not_mem_prime_iff_unit_in_stalk #align algebraic_geometry.LocallyRingedSpace.to_Γ_Spec_preim_basic_open_eq AlgebraicGeometry.LocallyRingedSpace.toΓSpec_preim_basicOpen_eq
Mathlib/AlgebraicGeometry/GammaSpecAdjunction.lean
91
95
theorem toΓSpec_continuous : Continuous X.toΓSpecFun := by
rw [isTopologicalBasis_basic_opens.continuous_iff] rintro _ ⟨r, rfl⟩ erw [X.toΓSpec_preim_basicOpen_eq r] exact (X.toRingedSpace.basicOpen r).2
false
import Mathlib.Analysis.NormedSpace.Spectrum import Mathlib.Topology.ContinuousFunction.NonUnitalFunctionalCalculus import Mathlib.Topology.ContinuousFunction.StoneWeierstrass section UniqueUnital section NNReal open NNReal variable {X : Type*} [TopologicalSpace X] variable {A : Type*} [TopologicalSpace A] [Ring A] [StarRing A] [Algebra ℝ A] [TopologicalRing A] section UniqueNonUnital section RCLike variable {𝕜 A : Type*} [RCLike 𝕜] open NonUnitalStarAlgebra in
Mathlib/Topology/ContinuousFunction/UniqueCFC.lean
207
218
theorem RCLike.uniqueNonUnitalContinuousFunctionalCalculus_of_compactSpace_quasispectrum [TopologicalSpace A] [T2Space A] [NonUnitalRing A] [StarRing A] [Module 𝕜 A] [IsScalarTower 𝕜 A A] [SMulCommClass 𝕜 A A] [h : ∀ a : A, CompactSpace (quasispectrum 𝕜 a)] : UniqueNonUnitalContinuousFunctionalCalculus 𝕜 A where eq_of_continuous_of_map_id s hs _inst h0 φ ψ hφ hψ h := by
rw [DFunLike.ext'_iff, ← Set.eqOn_univ, ← (ContinuousMapZero.adjoin_id_dense h0).closure_eq] refine Set.EqOn.closure (fun f hf ↦ ?_) hφ hψ rw [← NonUnitalStarAlgHom.mem_equalizer] apply adjoin_le ?_ hf rw [Set.singleton_subset_iff] exact h compactSpace_quasispectrum := h
false
import Mathlib.Analysis.Calculus.Deriv.Inv import Mathlib.Analysis.NormedSpace.BallAction import Mathlib.Analysis.SpecialFunctions.ExpDeriv import Mathlib.Analysis.InnerProductSpace.Calculus import Mathlib.Analysis.InnerProductSpace.PiL2 import Mathlib.Geometry.Manifold.Algebra.LieGroup import Mathlib.Geometry.Manifold.Instances.Real import Mathlib.Geometry.Manifold.MFDeriv.Basic #align_import geometry.manifold.instances.sphere from "leanprover-community/mathlib"@"0dc4079202c28226b2841a51eb6d3cc2135bb80f" variable {E : Type*} [NormedAddCommGroup E] [InnerProductSpace ℝ E] noncomputable section open Metric FiniteDimensional Function open scoped Manifold section SmoothManifold
Mathlib/Geometry/Manifold/Instances/Sphere.lean
385
386
theorem sphere_ext_iff (u v : sphere (0 : E) 1) : u = v ↔ ⟪(u : E), v⟫_ℝ = 1 := by
simp [Subtype.ext_iff, inner_eq_one_iff_of_norm_one]
false
import Mathlib.Topology.Category.Profinite.Basic import Mathlib.Topology.LocallyConstant.Basic import Mathlib.Topology.DiscreteQuotient import Mathlib.Topology.Category.TopCat.Limits.Cofiltered import Mathlib.Topology.Category.TopCat.Limits.Konig #align_import topology.category.Profinite.cofiltered_limit from "leanprover-community/mathlib"@"178a32653e369dce2da68dc6b2694e385d484ef1" namespace Profinite open scoped Classical open CategoryTheory open CategoryTheory.Limits -- This was a global instance prior to #13170. We may experiment with removing it. attribute [local instance] ConcreteCategory.instFunLike universe u v variable {J : Type v} [SmallCategory J] [IsCofiltered J] {F : J ⥤ Profinite.{max u v}} (C : Cone F) theorem exists_isClopen_of_cofiltered {U : Set C.pt} (hC : IsLimit C) (hU : IsClopen U) : ∃ (j : J) (V : Set (F.obj j)), IsClopen V ∧ U = C.π.app j ⁻¹' V := by -- First, we have the topological basis of the cofiltered limit obtained by pulling back -- clopen sets from the factors in the limit. By continuity, all such sets are again clopen. have hB := TopCat.isTopologicalBasis_cofiltered_limit.{u, v} (F ⋙ Profinite.toTopCat) (Profinite.toTopCat.mapCone C) (isLimitOfPreserves _ hC) (fun j => {W | IsClopen W}) ?_ (fun i => isClopen_univ) (fun i U1 U2 hU1 hU2 => hU1.inter hU2) ?_ rotate_left · intro i change TopologicalSpace.IsTopologicalBasis {W : Set (F.obj i) | IsClopen W} apply isTopologicalBasis_isClopen · rintro i j f V (hV : IsClopen _) exact ⟨hV.1.preimage ((F ⋙ toTopCat).map f).continuous, hV.2.preimage ((F ⋙ toTopCat).map f).continuous⟩ -- Porting note: `<;> continuity` fails -- Using this, since `U` is open, we can write `U` as a union of clopen sets all of which -- are preimages of clopens from the factors in the limit. obtain ⟨S, hS, h⟩ := hB.open_eq_sUnion hU.2 clear hB let j : S → J := fun s => (hS s.2).choose let V : ∀ s : S, Set (F.obj (j s)) := fun s => (hS s.2).choose_spec.choose have hV : ∀ s : S, IsClopen (V s) ∧ s.1 = C.π.app (j s) ⁻¹' V s := fun s => (hS s.2).choose_spec.choose_spec -- Since `U` is also closed, hence compact, it is covered by finitely many of the -- clopens constructed in the previous step. have hUo : ∀ (i : ↑S), IsOpen ((fun s ↦ (forget Profinite).map (C.π.app (j s)) ⁻¹' V s) i) := by intro s exact (hV s).1.2.preimage (C.π.app (j s)).continuous have hsU : U ⊆ ⋃ (i : ↑S), (fun s ↦ (forget Profinite).map (C.π.app (j s)) ⁻¹' V s) i := by dsimp only rw [h] rintro x ⟨T, hT, hx⟩ refine ⟨_, ⟨⟨T, hT⟩, rfl⟩, ?_⟩ dsimp only [forget_map_eq_coe] rwa [← (hV ⟨T, hT⟩).2] have := hU.1.isCompact.elim_finite_subcover (fun s : S => C.π.app (j s) ⁻¹' V s) hUo hsU -- Porting note: same remark as after `hB` -- We thus obtain a finite set `G : Finset J` and a clopen set of `F.obj j` for each -- `j ∈ G` such that `U` is the union of the preimages of these clopen sets. obtain ⟨G, hG⟩ := this -- Since `J` is cofiltered, we can find a single `j0` dominating all the `j ∈ G`. -- Pulling back all of the sets from the previous step to `F.obj j0` and taking a union, -- we obtain a clopen set in `F.obj j0` which works. obtain ⟨j0, hj0⟩ := IsCofiltered.inf_objs_exists (G.image j) let f : ∀ s ∈ G, j0 ⟶ j s := fun s hs => (hj0 (Finset.mem_image.mpr ⟨s, hs, rfl⟩)).some let W : S → Set (F.obj j0) := fun s => if hs : s ∈ G then F.map (f s hs) ⁻¹' V s else Set.univ -- Conclude, using the `j0` and the clopen set of `F.obj j0` obtained above. refine ⟨j0, ⋃ (s : S) (_ : s ∈ G), W s, ?_, ?_⟩ · apply isClopen_biUnion_finset intro s hs dsimp [W] rw [dif_pos hs] exact ⟨(hV s).1.1.preimage (F.map _).continuous, (hV s).1.2.preimage (F.map _).continuous⟩ · ext x constructor · intro hx simp_rw [W, Set.preimage_iUnion, Set.mem_iUnion] obtain ⟨_, ⟨s, rfl⟩, _, ⟨hs, rfl⟩, hh⟩ := hG hx refine ⟨s, hs, ?_⟩ rwa [dif_pos hs, ← Set.preimage_comp, ← Profinite.coe_comp, ← Functor.map_comp, C.w] · intro hx simp_rw [W, Set.preimage_iUnion, Set.mem_iUnion] at hx obtain ⟨s, hs, hx⟩ := hx rw [h] refine ⟨s.1, s.2, ?_⟩ rw [(hV s).2] rwa [dif_pos hs, ← Set.preimage_comp, ← Profinite.coe_comp, ← Functor.map_comp, C.w] at hx set_option linter.uppercaseLean3 false in #align Profinite.exists_clopen_of_cofiltered Profinite.exists_isClopen_of_cofiltered
Mathlib/Topology/Category/Profinite/CofilteredLimit.lean
116
126
theorem exists_locallyConstant_fin_two (hC : IsLimit C) (f : LocallyConstant C.pt (Fin 2)) : ∃ (j : J) (g : LocallyConstant (F.obj j) (Fin 2)), f = g.comap (C.π.app _) := by let U := f ⁻¹' {0}
let U := f ⁻¹' {0} have hU : IsClopen U := f.isLocallyConstant.isClopen_fiber _ obtain ⟨j, V, hV, h⟩ := exists_isClopen_of_cofiltered C hC hU use j, LocallyConstant.ofIsClopen hV apply LocallyConstant.locallyConstant_eq_of_fiber_zero_eq simp only [Fin.isValue, Functor.const_obj_obj, LocallyConstant.coe_comap, Set.preimage_comp, LocallyConstant.ofIsClopen_fiber_zero] -- This used to be `rw`, but we need `erw` after leanprover/lean4#2644 erw [← h]
true
import Mathlib.Data.ZMod.Basic import Mathlib.Algebra.Group.Nat import Mathlib.Tactic.IntervalCases import Mathlib.GroupTheory.SpecificGroups.Dihedral import Mathlib.GroupTheory.SpecificGroups.Cyclic #align_import group_theory.specific_groups.quaternion from "leanprover-community/mathlib"@"879155bff5af618b9062cbb2915347dafd749ad6" inductive QuaternionGroup (n : ℕ) : Type | a : ZMod (2 * n) → QuaternionGroup n | xa : ZMod (2 * n) → QuaternionGroup n deriving DecidableEq #align quaternion_group QuaternionGroup namespace QuaternionGroup variable {n : ℕ} private def mul : QuaternionGroup n → QuaternionGroup n → QuaternionGroup n | a i, a j => a (i + j) | a i, xa j => xa (j - i) | xa i, a j => xa (i + j) | xa i, xa j => a (n + j - i) private def one : QuaternionGroup n := a 0 instance : Inhabited (QuaternionGroup n) := ⟨one⟩ private def inv : QuaternionGroup n → QuaternionGroup n | a i => a (-i) | xa i => xa (n + i) instance : Group (QuaternionGroup n) where mul := mul mul_assoc := by rintro (i | i) (j | j) (k | k) <;> simp only [(· * ·), mul] <;> ring_nf congr calc -(n : ZMod (2 * n)) = 0 - n := by rw [zero_sub] _ = 2 * n - n := by norm_cast; simp _ = n := by ring one := one one_mul := by rintro (i | i) · exact congr_arg a (zero_add i) · exact congr_arg xa (sub_zero i) mul_one := by rintro (i | i) · exact congr_arg a (add_zero i) · exact congr_arg xa (add_zero i) inv := inv mul_left_inv := by rintro (i | i) · exact congr_arg a (neg_add_self i) · exact congr_arg a (sub_self (n + i)) @[simp] theorem a_mul_a (i j : ZMod (2 * n)) : a i * a j = a (i + j) := rfl #align quaternion_group.a_mul_a QuaternionGroup.a_mul_a @[simp] theorem a_mul_xa (i j : ZMod (2 * n)) : a i * xa j = xa (j - i) := rfl #align quaternion_group.a_mul_xa QuaternionGroup.a_mul_xa @[simp] theorem xa_mul_a (i j : ZMod (2 * n)) : xa i * a j = xa (i + j) := rfl #align quaternion_group.xa_mul_a QuaternionGroup.xa_mul_a @[simp] theorem xa_mul_xa (i j : ZMod (2 * n)) : xa i * xa j = a ((n : ZMod (2 * n)) + j - i) := rfl #align quaternion_group.xa_mul_xa QuaternionGroup.xa_mul_xa theorem one_def : (1 : QuaternionGroup n) = a 0 := rfl #align quaternion_group.one_def QuaternionGroup.one_def private def fintypeHelper : Sum (ZMod (2 * n)) (ZMod (2 * n)) ≃ QuaternionGroup n where invFun i := match i with | a j => Sum.inl j | xa j => Sum.inr j toFun i := match i with | Sum.inl j => a j | Sum.inr j => xa j left_inv := by rintro (x | x) <;> rfl right_inv := by rintro (x | x) <;> rfl def quaternionGroupZeroEquivDihedralGroupZero : QuaternionGroup 0 ≃* DihedralGroup 0 where toFun i := -- Porting note: Originally `QuaternionGroup.recOn i DihedralGroup.r DihedralGroup.sr` match i with | a j => DihedralGroup.r j | xa j => DihedralGroup.sr j invFun i := match i with | DihedralGroup.r j => a j | DihedralGroup.sr j => xa j left_inv := by rintro (k | k) <;> rfl right_inv := by rintro (k | k) <;> rfl map_mul' := by rintro (k | k) (l | l) <;> simp #align quaternion_group.quaternion_group_zero_equiv_dihedral_group_zero QuaternionGroup.quaternionGroupZeroEquivDihedralGroupZero instance [NeZero n] : Fintype (QuaternionGroup n) := Fintype.ofEquiv _ fintypeHelper instance : Nontrivial (QuaternionGroup n) := ⟨⟨a 0, xa 0, by revert n; simp⟩⟩ -- Porting note: `revert n; simp` was `decide` theorem card [NeZero n] : Fintype.card (QuaternionGroup n) = 4 * n := by rw [← Fintype.card_eq.mpr ⟨fintypeHelper⟩, Fintype.card_sum, ZMod.card, two_mul] ring #align quaternion_group.card QuaternionGroup.card @[simp] theorem a_one_pow (k : ℕ) : (a 1 : QuaternionGroup n) ^ k = a k := by induction' k with k IH · rw [Nat.cast_zero]; rfl · rw [pow_succ, IH, a_mul_a] congr 1 norm_cast #align quaternion_group.a_one_pow QuaternionGroup.a_one_pow -- @[simp] -- Porting note: simp changes this to `a 0 = 1`, so this is no longer a good simp lemma. theorem a_one_pow_n : (a 1 : QuaternionGroup n) ^ (2 * n) = 1 := by rw [a_one_pow, one_def] congr 1 exact ZMod.natCast_self _ #align quaternion_group.a_one_pow_n QuaternionGroup.a_one_pow_n @[simp] theorem xa_sq (i : ZMod (2 * n)) : xa i ^ 2 = a n := by simp [sq] #align quaternion_group.xa_sq QuaternionGroup.xa_sq @[simp] theorem xa_pow_four (i : ZMod (2 * n)) : xa i ^ 4 = 1 := by rw [pow_succ, pow_succ, sq, xa_mul_xa, a_mul_xa, xa_mul_xa, add_sub_cancel_right, add_sub_assoc, sub_sub_cancel] norm_cast rw [← two_mul] simp [one_def] #align quaternion_group.xa_pow_four QuaternionGroup.xa_pow_four @[simp]
Mathlib/GroupTheory/SpecificGroups/Quaternion.lean
211
222
theorem orderOf_xa [NeZero n] (i : ZMod (2 * n)) : orderOf (xa i) = 4 := by change _ = 2 ^ 2
change _ = 2 ^ 2 haveI : Fact (Nat.Prime 2) := Fact.mk Nat.prime_two apply orderOf_eq_prime_pow · intro h simp only [pow_one, xa_sq] at h injection h with h' apply_fun ZMod.val at h' apply_fun (· / n) at h' simp only [ZMod.val_natCast, ZMod.val_zero, Nat.zero_div, Nat.mod_mul_left_div_self, Nat.div_self (NeZero.pos n)] at h' · norm_num
true
import Mathlib.NumberTheory.FLT.Basic import Mathlib.NumberTheory.PythagoreanTriples import Mathlib.RingTheory.Coprime.Lemmas import Mathlib.Tactic.LinearCombination #align_import number_theory.fermat4 from "leanprover-community/mathlib"@"10b4e499f43088dd3bb7b5796184ad5216648ab1" noncomputable section open scoped Classical def Fermat42 (a b c : ℤ) : Prop := a ≠ 0 ∧ b ≠ 0 ∧ a ^ 4 + b ^ 4 = c ^ 2 #align fermat_42 Fermat42 namespace Fermat42 theorem comm {a b c : ℤ} : Fermat42 a b c ↔ Fermat42 b a c := by delta Fermat42 rw [add_comm] tauto #align fermat_42.comm Fermat42.comm theorem mul {a b c k : ℤ} (hk0 : k ≠ 0) : Fermat42 a b c ↔ Fermat42 (k * a) (k * b) (k ^ 2 * c) := by delta Fermat42 constructor · intro f42 constructor · exact mul_ne_zero hk0 f42.1 constructor · exact mul_ne_zero hk0 f42.2.1 · have H : a ^ 4 + b ^ 4 = c ^ 2 := f42.2.2 linear_combination k ^ 4 * H · intro f42 constructor · exact right_ne_zero_of_mul f42.1 constructor · exact right_ne_zero_of_mul f42.2.1 apply (mul_right_inj' (pow_ne_zero 4 hk0)).mp linear_combination f42.2.2 #align fermat_42.mul Fermat42.mul theorem ne_zero {a b c : ℤ} (h : Fermat42 a b c) : c ≠ 0 := by apply ne_zero_pow two_ne_zero _; apply ne_of_gt rw [← h.2.2, (by ring : a ^ 4 + b ^ 4 = (a ^ 2) ^ 2 + (b ^ 2) ^ 2)] exact add_pos (sq_pos_of_ne_zero (pow_ne_zero 2 h.1)) (sq_pos_of_ne_zero (pow_ne_zero 2 h.2.1)) #align fermat_42.ne_zero Fermat42.ne_zero def Minimal (a b c : ℤ) : Prop := Fermat42 a b c ∧ ∀ a1 b1 c1 : ℤ, Fermat42 a1 b1 c1 → Int.natAbs c ≤ Int.natAbs c1 #align fermat_42.minimal Fermat42.Minimal theorem exists_minimal {a b c : ℤ} (h : Fermat42 a b c) : ∃ a0 b0 c0, Minimal a0 b0 c0 := by let S : Set ℕ := { n | ∃ s : ℤ × ℤ × ℤ, Fermat42 s.1 s.2.1 s.2.2 ∧ n = Int.natAbs s.2.2 } have S_nonempty : S.Nonempty := by use Int.natAbs c rw [Set.mem_setOf_eq] use ⟨a, ⟨b, c⟩⟩ let m : ℕ := Nat.find S_nonempty have m_mem : m ∈ S := Nat.find_spec S_nonempty rcases m_mem with ⟨s0, hs0, hs1⟩ use s0.1, s0.2.1, s0.2.2, hs0 intro a1 b1 c1 h1 rw [← hs1] apply Nat.find_min' use ⟨a1, ⟨b1, c1⟩⟩ #align fermat_42.exists_minimal Fermat42.exists_minimal
Mathlib/NumberTheory/FLT/Four.lean
89
105
theorem coprime_of_minimal {a b c : ℤ} (h : Minimal a b c) : IsCoprime a b := by apply Int.gcd_eq_one_iff_coprime.mp
apply Int.gcd_eq_one_iff_coprime.mp by_contra hab obtain ⟨p, hp, hpa, hpb⟩ := Nat.Prime.not_coprime_iff_dvd.mp hab obtain ⟨a1, rfl⟩ := Int.natCast_dvd.mpr hpa obtain ⟨b1, rfl⟩ := Int.natCast_dvd.mpr hpb have hpc : (p : ℤ) ^ 2 ∣ c := by rw [← Int.pow_dvd_pow_iff two_ne_zero, ← h.1.2.2] apply Dvd.intro (a1 ^ 4 + b1 ^ 4) ring obtain ⟨c1, rfl⟩ := hpc have hf : Fermat42 a1 b1 c1 := (Fermat42.mul (Int.natCast_ne_zero.mpr (Nat.Prime.ne_zero hp))).mpr h.1 apply Nat.le_lt_asymm (h.2 _ _ _ hf) rw [Int.natAbs_mul, lt_mul_iff_one_lt_left, Int.natAbs_pow, Int.natAbs_ofNat] · exact Nat.one_lt_pow two_ne_zero (Nat.Prime.one_lt hp) · exact Nat.pos_of_ne_zero (Int.natAbs_ne_zero.2 (ne_zero hf))
true
import Mathlib.LinearAlgebra.Ray import Mathlib.LinearAlgebra.Determinant #align_import linear_algebra.orientation from "leanprover-community/mathlib"@"0c1d80f5a86b36c1db32e021e8d19ae7809d5b79" noncomputable section section OrderedCommSemiring variable (R : Type*) [StrictOrderedCommSemiring R] variable (M : Type*) [AddCommMonoid M] [Module R M] variable {N : Type*} [AddCommMonoid N] [Module R N] variable (ι ι' : Type*) abbrev Orientation := Module.Ray R (M [⋀^ι]→ₗ[R] R) #align orientation Orientation class Module.Oriented where positiveOrientation : Orientation R M ι #align module.oriented Module.Oriented export Module.Oriented (positiveOrientation) variable {R M} def Orientation.map (e : M ≃ₗ[R] N) : Orientation R M ι ≃ Orientation R N ι := Module.Ray.map <| AlternatingMap.domLCongr R R ι R e #align orientation.map Orientation.map @[simp] theorem Orientation.map_apply (e : M ≃ₗ[R] N) (v : M [⋀^ι]→ₗ[R] R) (hv : v ≠ 0) : Orientation.map ι e (rayOfNeZero _ v hv) = rayOfNeZero _ (v.compLinearMap e.symm) (mt (v.compLinearEquiv_eq_zero_iff e.symm).mp hv) := rfl #align orientation.map_apply Orientation.map_apply @[simp]
Mathlib/LinearAlgebra/Orientation.lean
74
75
theorem Orientation.map_refl : (Orientation.map ι <| LinearEquiv.refl R M) = Equiv.refl _ := by
rw [Orientation.map, AlternatingMap.domLCongr_refl, Module.Ray.map_refl]
true
import Mathlib.Algebra.Polynomial.Splits #align_import algebra.cubic_discriminant from "leanprover-community/mathlib"@"930133160e24036d5242039fe4972407cd4f1222" noncomputable section @[ext] structure Cubic (R : Type*) where (a b c d : R) #align cubic Cubic namespace Cubic open Cubic Polynomial open Polynomial variable {R S F K : Type*} instance [Inhabited R] : Inhabited (Cubic R) := ⟨⟨default, default, default, default⟩⟩ instance [Zero R] : Zero (Cubic R) := ⟨⟨0, 0, 0, 0⟩⟩ section Basic variable {P Q : Cubic R} {a b c d a' b' c' d' : R} [Semiring R] def toPoly (P : Cubic R) : R[X] := C P.a * X ^ 3 + C P.b * X ^ 2 + C P.c * X + C P.d #align cubic.to_poly Cubic.toPoly theorem C_mul_prod_X_sub_C_eq [CommRing S] {w x y z : S} : C w * (X - C x) * (X - C y) * (X - C z) = toPoly ⟨w, w * -(x + y + z), w * (x * y + x * z + y * z), w * -(x * y * z)⟩ := by simp only [toPoly, C_neg, C_add, C_mul] ring1 set_option linter.uppercaseLean3 false in #align cubic.C_mul_prod_X_sub_C_eq Cubic.C_mul_prod_X_sub_C_eq theorem prod_X_sub_C_eq [CommRing S] {x y z : S} : (X - C x) * (X - C y) * (X - C z) = toPoly ⟨1, -(x + y + z), x * y + x * z + y * z, -(x * y * z)⟩ := by rw [← one_mul <| X - C x, ← C_1, C_mul_prod_X_sub_C_eq, one_mul, one_mul, one_mul] set_option linter.uppercaseLean3 false in #align cubic.prod_X_sub_C_eq Cubic.prod_X_sub_C_eq section Coeff private theorem coeffs : (∀ n > 3, P.toPoly.coeff n = 0) ∧ P.toPoly.coeff 3 = P.a ∧ P.toPoly.coeff 2 = P.b ∧ P.toPoly.coeff 1 = P.c ∧ P.toPoly.coeff 0 = P.d := by simp only [toPoly, coeff_add, coeff_C, coeff_C_mul_X, coeff_C_mul_X_pow] set_option tactic.skipAssignedInstances false in norm_num intro n hn repeat' rw [if_neg] any_goals linarith only [hn] repeat' rw [zero_add] @[simp] theorem coeff_eq_zero {n : ℕ} (hn : 3 < n) : P.toPoly.coeff n = 0 := coeffs.1 n hn #align cubic.coeff_eq_zero Cubic.coeff_eq_zero @[simp] theorem coeff_eq_a : P.toPoly.coeff 3 = P.a := coeffs.2.1 #align cubic.coeff_eq_a Cubic.coeff_eq_a @[simp] theorem coeff_eq_b : P.toPoly.coeff 2 = P.b := coeffs.2.2.1 #align cubic.coeff_eq_b Cubic.coeff_eq_b @[simp] theorem coeff_eq_c : P.toPoly.coeff 1 = P.c := coeffs.2.2.2.1 #align cubic.coeff_eq_c Cubic.coeff_eq_c @[simp] theorem coeff_eq_d : P.toPoly.coeff 0 = P.d := coeffs.2.2.2.2 #align cubic.coeff_eq_d Cubic.coeff_eq_d theorem a_of_eq (h : P.toPoly = Q.toPoly) : P.a = Q.a := by rw [← coeff_eq_a, h, coeff_eq_a] #align cubic.a_of_eq Cubic.a_of_eq theorem b_of_eq (h : P.toPoly = Q.toPoly) : P.b = Q.b := by rw [← coeff_eq_b, h, coeff_eq_b] #align cubic.b_of_eq Cubic.b_of_eq theorem c_of_eq (h : P.toPoly = Q.toPoly) : P.c = Q.c := by rw [← coeff_eq_c, h, coeff_eq_c] #align cubic.c_of_eq Cubic.c_of_eq
Mathlib/Algebra/CubicDiscriminant.lean
130
130
theorem d_of_eq (h : P.toPoly = Q.toPoly) : P.d = Q.d := by
rw [← coeff_eq_d, h, coeff_eq_d]
true
import Mathlib.Algebra.CharP.Invertible import Mathlib.Algebra.MvPolynomial.Variables import Mathlib.Algebra.MvPolynomial.CommRing import Mathlib.Algebra.MvPolynomial.Expand import Mathlib.Data.Fintype.BigOperators import Mathlib.Data.ZMod.Basic #align_import ring_theory.witt_vector.witt_polynomial from "leanprover-community/mathlib"@"c3019c79074b0619edb4b27553a91b2e82242395" open MvPolynomial open Finset hiding map open Finsupp (single) --attribute [-simp] coe_eval₂_hom variable (p : ℕ) variable (R : Type*) [CommRing R] [DecidableEq R] noncomputable def wittPolynomial (n : ℕ) : MvPolynomial ℕ R := ∑ i ∈ range (n + 1), monomial (single i (p ^ (n - i))) ((p : R) ^ i) #align witt_polynomial wittPolynomial theorem wittPolynomial_eq_sum_C_mul_X_pow (n : ℕ) : wittPolynomial p R n = ∑ i ∈ range (n + 1), C ((p : R) ^ i) * X i ^ p ^ (n - i) := by apply sum_congr rfl rintro i - rw [monomial_eq, Finsupp.prod_single_index] rw [pow_zero] set_option linter.uppercaseLean3 false in #align witt_polynomial_eq_sum_C_mul_X_pow wittPolynomial_eq_sum_C_mul_X_pow -- 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 _ open Witt open MvPolynomial section variable {R} {S : Type*} [CommRing S] @[simp] theorem map_wittPolynomial (f : R →+* S) (n : ℕ) : map f (W n) = W n := by rw [wittPolynomial, map_sum, wittPolynomial] refine sum_congr rfl fun i _ => ?_ rw [map_monomial, RingHom.map_pow, map_natCast] #align map_witt_polynomial map_wittPolynomial variable (R) @[simp] theorem constantCoeff_wittPolynomial [hp : Fact p.Prime] (n : ℕ) : constantCoeff (wittPolynomial p R n) = 0 := by simp only [wittPolynomial, map_sum, constantCoeff_monomial] rw [sum_eq_zero] rintro i _ rw [if_neg] rw [Finsupp.single_eq_zero] exact ne_of_gt (pow_pos hp.1.pos _) #align constant_coeff_witt_polynomial constantCoeff_wittPolynomial @[simp] theorem wittPolynomial_zero : wittPolynomial p R 0 = X 0 := by simp only [wittPolynomial, X, sum_singleton, range_one, pow_zero, zero_add, tsub_self] #align witt_polynomial_zero wittPolynomial_zero @[simp] theorem wittPolynomial_one : wittPolynomial p R 1 = C (p : R) * X 1 + X 0 ^ p := by simp only [wittPolynomial_eq_sum_C_mul_X_pow, sum_range_succ_comm, range_one, sum_singleton, one_mul, pow_one, C_1, pow_zero, tsub_self, tsub_zero] #align witt_polynomial_one wittPolynomial_one theorem aeval_wittPolynomial {A : Type*} [CommRing A] [Algebra R A] (f : ℕ → A) (n : ℕ) : aeval f (W_ R n) = ∑ i ∈ range (n + 1), (p : A) ^ i * f i ^ p ^ (n - i) := by simp [wittPolynomial, AlgHom.map_sum, aeval_monomial, Finsupp.prod_single_index] #align aeval_witt_polynomial aeval_wittPolynomial @[simp] theorem wittPolynomial_zmod_self (n : ℕ) : W_ (ZMod (p ^ (n + 1))) (n + 1) = expand p (W_ (ZMod (p ^ (n + 1))) n) := by simp only [wittPolynomial_eq_sum_C_mul_X_pow] rw [sum_range_succ, ← Nat.cast_pow, CharP.cast_eq_zero (ZMod (p ^ (n + 1))) (p ^ (n + 1)), C_0, zero_mul, add_zero, AlgHom.map_sum, sum_congr rfl] intro k hk rw [AlgHom.map_mul, AlgHom.map_pow, expand_X, algHom_C, ← pow_mul, ← pow_succ'] congr rw [mem_range] at hk rw [add_comm, add_tsub_assoc_of_le (Nat.lt_succ_iff.mp hk), ← add_comm] #align witt_polynomial_zmod_self wittPolynomial_zmod_self end noncomputable def xInTermsOfW [Invertible (p : R)] : ℕ → MvPolynomial ℕ R | n => (X n - ∑ i : Fin n, C ((p : R) ^ (i : ℕ)) * xInTermsOfW i ^ p ^ (n - (i : ℕ))) * C ((⅟ p : R) ^ n) set_option linter.uppercaseLean3 false in #align X_in_terms_of_W xInTermsOfW theorem xInTermsOfW_eq [Invertible (p : R)] {n : ℕ} : xInTermsOfW p R n = (X n - ∑ i ∈ range n, C ((p: R) ^ i) * xInTermsOfW p R i ^ p ^ (n - i)) * C ((⅟p : R) ^ n) := by rw [xInTermsOfW, ← Fin.sum_univ_eq_sum_range] set_option linter.uppercaseLean3 false in #align X_in_terms_of_W_eq xInTermsOfW_eq @[simp]
Mathlib/RingTheory/WittVector/WittPolynomial.lean
218
234
theorem constantCoeff_xInTermsOfW [hp : Fact p.Prime] [Invertible (p : R)] (n : ℕ) : constantCoeff (xInTermsOfW p R n) = 0 := by apply Nat.strongInductionOn n; clear n
apply Nat.strongInductionOn n; clear n intro n IH rw [xInTermsOfW_eq, mul_comm, RingHom.map_mul, RingHom.map_sub, map_sum, constantCoeff_C, constantCoeff_X, zero_sub, mul_neg, neg_eq_zero] -- Porting note: here, we should be able to do `rw [sum_eq_zero]`, but the goal that -- is created is not what we expect, and the sum is not replaced by zero... -- is it a bug in `rw` tactic? refine Eq.trans (?_ : _ = ((⅟↑p : R) ^ n)* 0) (mul_zero _) congr 1 rw [sum_eq_zero] intro m H rw [mem_range] at H simp only [RingHom.map_mul, RingHom.map_pow, map_natCast, IH m H] rw [zero_pow, mul_zero] exact pow_ne_zero _ hp.1.ne_zero
true
import Mathlib.Data.List.Cycle import Mathlib.GroupTheory.Perm.Cycle.Type import Mathlib.GroupTheory.Perm.List #align_import group_theory.perm.cycle.concrete from "leanprover-community/mathlib"@"00638177efd1b2534fc5269363ebf42a7871df9a" open Equiv Equiv.Perm List variable {α : Type*} namespace Equiv.Perm section Fintype variable [Fintype α] [DecidableEq α] (p : Equiv.Perm α) (x : α) def toList : List α := (List.range (cycleOf p x).support.card).map fun k => (p ^ k) x #align equiv.perm.to_list Equiv.Perm.toList @[simp] theorem toList_one : toList (1 : Perm α) x = [] := by simp [toList, cycleOf_one] #align equiv.perm.to_list_one Equiv.Perm.toList_one @[simp] theorem toList_eq_nil_iff {p : Perm α} {x} : toList p x = [] ↔ x ∉ p.support := by simp [toList] #align equiv.perm.to_list_eq_nil_iff Equiv.Perm.toList_eq_nil_iff @[simp] theorem length_toList : length (toList p x) = (cycleOf p x).support.card := by simp [toList] #align equiv.perm.length_to_list Equiv.Perm.length_toList theorem toList_ne_singleton (y : α) : toList p x ≠ [y] := by intro H simpa [card_support_ne_one] using congr_arg length H #align equiv.perm.to_list_ne_singleton Equiv.Perm.toList_ne_singleton theorem two_le_length_toList_iff_mem_support {p : Perm α} {x : α} : 2 ≤ length (toList p x) ↔ x ∈ p.support := by simp #align equiv.perm.two_le_length_to_list_iff_mem_support Equiv.Perm.two_le_length_toList_iff_mem_support theorem length_toList_pos_of_mem_support (h : x ∈ p.support) : 0 < length (toList p x) := zero_lt_two.trans_le (two_le_length_toList_iff_mem_support.mpr h) #align equiv.perm.length_to_list_pos_of_mem_support Equiv.Perm.length_toList_pos_of_mem_support theorem get_toList (n : ℕ) (hn : n < length (toList p x)) : (toList p x).get ⟨n, hn⟩ = (p ^ n) x := by simp [toList] theorem toList_get_zero (h : x ∈ p.support) : (toList p x).get ⟨0, (length_toList_pos_of_mem_support _ _ h)⟩ = x := by simp [toList] set_option linter.deprecated false in @[deprecated get_toList (since := "2024-05-08")] theorem nthLe_toList (n : ℕ) (hn : n < length (toList p x)) : (toList p x).nthLe n hn = (p ^ n) x := by simp [toList] #align equiv.perm.nth_le_to_list Equiv.Perm.nthLe_toList set_option linter.deprecated false in @[deprecated toList_get_zero (since := "2024-05-08")]
Mathlib/GroupTheory/Perm/Cycle/Concrete.lean
259
260
theorem toList_nthLe_zero (h : x ∈ p.support) : (toList p x).nthLe 0 (length_toList_pos_of_mem_support _ _ h) = x := by
simp [toList]
true
import Mathlib.MeasureTheory.PiSystem import Mathlib.Order.OmegaCompletePartialOrder import Mathlib.Topology.Constructions import Mathlib.MeasureTheory.MeasurableSpace.Basic open Set namespace MeasureTheory variable {ι : Type _} {α : ι → Type _} section cylinder def cylinder (s : Finset ι) (S : Set (∀ i : s, α i)) : Set (∀ i, α i) := (fun (f : ∀ i, α i) (i : s) ↦ f i) ⁻¹' S @[simp] theorem mem_cylinder (s : Finset ι) (S : Set (∀ i : s, α i)) (f : ∀ i, α i) : f ∈ cylinder s S ↔ (fun i : s ↦ f i) ∈ S := mem_preimage @[simp] theorem cylinder_empty (s : Finset ι) : cylinder s (∅ : Set (∀ i : s, α i)) = ∅ := by rw [cylinder, preimage_empty] @[simp] theorem cylinder_univ (s : Finset ι) : cylinder s (univ : Set (∀ i : s, α i)) = univ := by rw [cylinder, preimage_univ] @[simp] theorem cylinder_eq_empty_iff [h_nonempty : Nonempty (∀ i, α i)] (s : Finset ι) (S : Set (∀ i : s, α i)) : cylinder s S = ∅ ↔ S = ∅ := by refine ⟨fun h ↦ ?_, fun h ↦ by (rw [h]; exact cylinder_empty _)⟩ by_contra hS rw [← Ne, ← nonempty_iff_ne_empty] at hS let f := hS.some have hf : f ∈ S := hS.choose_spec classical let f' : ∀ i, α i := fun i ↦ if hi : i ∈ s then f ⟨i, hi⟩ else h_nonempty.some i have hf' : f' ∈ cylinder s S := by rw [mem_cylinder] simpa only [f', Finset.coe_mem, dif_pos] rw [h] at hf' exact not_mem_empty _ hf' theorem inter_cylinder (s₁ s₂ : Finset ι) (S₁ : Set (∀ i : s₁, α i)) (S₂ : Set (∀ i : s₂, α i)) [DecidableEq ι] : cylinder s₁ S₁ ∩ cylinder s₂ S₂ = cylinder (s₁ ∪ s₂) ((fun f ↦ fun j : s₁ ↦ f ⟨j, Finset.mem_union_left s₂ j.prop⟩) ⁻¹' S₁ ∩ (fun f ↦ fun j : s₂ ↦ f ⟨j, Finset.mem_union_right s₁ j.prop⟩) ⁻¹' S₂) := by ext1 f; simp only [mem_inter_iff, mem_cylinder, mem_setOf_eq]; rfl theorem inter_cylinder_same (s : Finset ι) (S₁ : Set (∀ i : s, α i)) (S₂ : Set (∀ i : s, α i)) : cylinder s S₁ ∩ cylinder s S₂ = cylinder s (S₁ ∩ S₂) := by classical rw [inter_cylinder]; rfl theorem union_cylinder (s₁ s₂ : Finset ι) (S₁ : Set (∀ i : s₁, α i)) (S₂ : Set (∀ i : s₂, α i)) [DecidableEq ι] : cylinder s₁ S₁ ∪ cylinder s₂ S₂ = cylinder (s₁ ∪ s₂) ((fun f ↦ fun j : s₁ ↦ f ⟨j, Finset.mem_union_left s₂ j.prop⟩) ⁻¹' S₁ ∪ (fun f ↦ fun j : s₂ ↦ f ⟨j, Finset.mem_union_right s₁ j.prop⟩) ⁻¹' S₂) := by ext1 f; simp only [mem_union, mem_cylinder, mem_setOf_eq]; rfl theorem union_cylinder_same (s : Finset ι) (S₁ : Set (∀ i : s, α i)) (S₂ : Set (∀ i : s, α i)) : cylinder s S₁ ∪ cylinder s S₂ = cylinder s (S₁ ∪ S₂) := by classical rw [union_cylinder]; rfl theorem compl_cylinder (s : Finset ι) (S : Set (∀ i : s, α i)) : (cylinder s S)ᶜ = cylinder s (Sᶜ) := by ext1 f; simp only [mem_compl_iff, mem_cylinder] theorem diff_cylinder_same (s : Finset ι) (S T : Set (∀ i : s, α i)) : cylinder s S \ cylinder s T = cylinder s (S \ T) := by ext1 f; simp only [mem_diff, mem_cylinder] theorem eq_of_cylinder_eq_of_subset [h_nonempty : Nonempty (∀ i, α i)] {I J : Finset ι} {S : Set (∀ i : I, α i)} {T : Set (∀ i : J, α i)} (h_eq : cylinder I S = cylinder J T) (hJI : J ⊆ I) : S = (fun f : ∀ i : I, α i ↦ fun j : J ↦ f ⟨j, hJI j.prop⟩) ⁻¹' T := by rw [Set.ext_iff] at h_eq simp only [mem_cylinder] at h_eq ext1 f simp only [mem_preimage] classical specialize h_eq fun i ↦ if hi : i ∈ I then f ⟨i, hi⟩ else h_nonempty.some i have h_mem : ∀ j : J, ↑j ∈ I := fun j ↦ hJI j.prop simp only [Finset.coe_mem, dite_true, h_mem] at h_eq exact h_eq theorem cylinder_eq_cylinder_union [DecidableEq ι] (I : Finset ι) (S : Set (∀ i : I, α i)) (J : Finset ι) : cylinder I S = cylinder (I ∪ J) ((fun f ↦ fun j : I ↦ f ⟨j, Finset.mem_union_left J j.prop⟩) ⁻¹' S) := by ext1 f; simp only [mem_cylinder, mem_preimage]
Mathlib/MeasureTheory/Constructions/Cylinders.lean
237
244
theorem disjoint_cylinder_iff [Nonempty (∀ i, α i)] {s t : Finset ι} {S : Set (∀ i : s, α i)} {T : Set (∀ i : t, α i)} [DecidableEq ι] : Disjoint (cylinder s S) (cylinder t T) ↔ Disjoint ((fun f : ∀ i : (s ∪ t : Finset ι), α i ↦ fun j : s ↦ f ⟨j, Finset.mem_union_left t j.prop⟩) ⁻¹' S) ((fun f ↦ fun j : t ↦ f ⟨j, Finset.mem_union_right s j.prop⟩) ⁻¹' T) := by
simp_rw [Set.disjoint_iff, subset_empty_iff, inter_cylinder, cylinder_eq_empty_iff]
true
import Mathlib.Analysis.NormedSpace.PiLp import Mathlib.Analysis.InnerProductSpace.PiL2 #align_import analysis.matrix from "leanprover-community/mathlib"@"46b633fd842bef9469441c0209906f6dddd2b4f5" noncomputable section open scoped NNReal Matrix namespace Matrix variable {R l m n α β : Type*} [Fintype l] [Fintype m] [Fintype n] section LinfLinf section SeminormedAddCommGroup variable [SeminormedAddCommGroup α] [SeminormedAddCommGroup β] protected def seminormedAddCommGroup : SeminormedAddCommGroup (Matrix m n α) := Pi.seminormedAddCommGroup #align matrix.seminormed_add_comm_group Matrix.seminormedAddCommGroup attribute [local instance] Matrix.seminormedAddCommGroup -- Porting note (#10756): new theorem (along with all the uses of this lemma below) theorem norm_def (A : Matrix m n α) : ‖A‖ = ‖fun i j => A i j‖ := rfl lemma norm_eq_sup_sup_nnnorm (A : Matrix m n α) : ‖A‖ = Finset.sup Finset.univ fun i ↦ Finset.sup Finset.univ fun j ↦ ‖A i j‖₊ := by simp_rw [Matrix.norm_def, Pi.norm_def, Pi.nnnorm_def] -- Porting note (#10756): new theorem (along with all the uses of this lemma below) theorem nnnorm_def (A : Matrix m n α) : ‖A‖₊ = ‖fun i j => A i j‖₊ := rfl theorem norm_le_iff {r : ℝ} (hr : 0 ≤ r) {A : Matrix m n α} : ‖A‖ ≤ r ↔ ∀ i j, ‖A i j‖ ≤ r := by simp_rw [norm_def, pi_norm_le_iff_of_nonneg hr] #align matrix.norm_le_iff Matrix.norm_le_iff theorem nnnorm_le_iff {r : ℝ≥0} {A : Matrix m n α} : ‖A‖₊ ≤ r ↔ ∀ i j, ‖A i j‖₊ ≤ r := by simp_rw [nnnorm_def, pi_nnnorm_le_iff] #align matrix.nnnorm_le_iff Matrix.nnnorm_le_iff theorem norm_lt_iff {r : ℝ} (hr : 0 < r) {A : Matrix m n α} : ‖A‖ < r ↔ ∀ i j, ‖A i j‖ < r := by simp_rw [norm_def, pi_norm_lt_iff hr] #align matrix.norm_lt_iff Matrix.norm_lt_iff theorem nnnorm_lt_iff {r : ℝ≥0} (hr : 0 < r) {A : Matrix m n α} : ‖A‖₊ < r ↔ ∀ i j, ‖A i j‖₊ < r := by simp_rw [nnnorm_def, pi_nnnorm_lt_iff hr] #align matrix.nnnorm_lt_iff Matrix.nnnorm_lt_iff theorem norm_entry_le_entrywise_sup_norm (A : Matrix m n α) {i : m} {j : n} : ‖A i j‖ ≤ ‖A‖ := (norm_le_pi_norm (A i) j).trans (norm_le_pi_norm A i) #align matrix.norm_entry_le_entrywise_sup_norm Matrix.norm_entry_le_entrywise_sup_norm theorem nnnorm_entry_le_entrywise_sup_nnnorm (A : Matrix m n α) {i : m} {j : n} : ‖A i j‖₊ ≤ ‖A‖₊ := (nnnorm_le_pi_nnnorm (A i) j).trans (nnnorm_le_pi_nnnorm A i) #align matrix.nnnorm_entry_le_entrywise_sup_nnnorm Matrix.nnnorm_entry_le_entrywise_sup_nnnorm @[simp] theorem nnnorm_map_eq (A : Matrix m n α) (f : α → β) (hf : ∀ a, ‖f a‖₊ = ‖a‖₊) : ‖A.map f‖₊ = ‖A‖₊ := by simp only [nnnorm_def, Pi.nnnorm_def, Matrix.map_apply, hf] #align matrix.nnnorm_map_eq Matrix.nnnorm_map_eq @[simp] theorem norm_map_eq (A : Matrix m n α) (f : α → β) (hf : ∀ a, ‖f a‖ = ‖a‖) : ‖A.map f‖ = ‖A‖ := (congr_arg ((↑) : ℝ≥0 → ℝ) <| nnnorm_map_eq A f fun a => Subtype.ext <| hf a : _) #align matrix.norm_map_eq Matrix.norm_map_eq @[simp] theorem nnnorm_transpose (A : Matrix m n α) : ‖Aᵀ‖₊ = ‖A‖₊ := Finset.sup_comm _ _ _ #align matrix.nnnorm_transpose Matrix.nnnorm_transpose @[simp] theorem norm_transpose (A : Matrix m n α) : ‖Aᵀ‖ = ‖A‖ := congr_arg ((↑) : ℝ≥0 → ℝ) <| nnnorm_transpose A #align matrix.norm_transpose Matrix.norm_transpose @[simp] theorem nnnorm_conjTranspose [StarAddMonoid α] [NormedStarGroup α] (A : Matrix m n α) : ‖Aᴴ‖₊ = ‖A‖₊ := (nnnorm_map_eq _ _ nnnorm_star).trans A.nnnorm_transpose #align matrix.nnnorm_conj_transpose Matrix.nnnorm_conjTranspose @[simp] theorem norm_conjTranspose [StarAddMonoid α] [NormedStarGroup α] (A : Matrix m n α) : ‖Aᴴ‖ = ‖A‖ := congr_arg ((↑) : ℝ≥0 → ℝ) <| nnnorm_conjTranspose A #align matrix.norm_conj_transpose Matrix.norm_conjTranspose instance [StarAddMonoid α] [NormedStarGroup α] : NormedStarGroup (Matrix m m α) := ⟨norm_conjTranspose⟩ @[simp] theorem nnnorm_col (v : m → α) : ‖col v‖₊ = ‖v‖₊ := by simp [nnnorm_def, Pi.nnnorm_def] #align matrix.nnnorm_col Matrix.nnnorm_col @[simp] theorem norm_col (v : m → α) : ‖col v‖ = ‖v‖ := congr_arg ((↑) : ℝ≥0 → ℝ) <| nnnorm_col v #align matrix.norm_col Matrix.norm_col @[simp]
Mathlib/Analysis/Matrix.lean
161
162
theorem nnnorm_row (v : n → α) : ‖row v‖₊ = ‖v‖₊ := by
simp [nnnorm_def, Pi.nnnorm_def]
true
import Mathlib.Analysis.InnerProductSpace.PiL2 import Mathlib.LinearAlgebra.Matrix.Block #align_import analysis.inner_product_space.gram_schmidt_ortho from "leanprover-community/mathlib"@"1a4df69ca1a9a0e5e26bfe12e2b92814216016d0" open Finset Submodule FiniteDimensional variable (𝕜 : Type*) {E : Type*} [RCLike 𝕜] [NormedAddCommGroup E] [InnerProductSpace 𝕜 E] variable {ι : Type*} [LinearOrder ι] [LocallyFiniteOrderBot ι] [IsWellOrder ι (· < ·)] attribute [local instance] IsWellOrder.toHasWellFounded local notation "⟪" x ", " y "⟫" => @inner 𝕜 _ _ x y noncomputable def gramSchmidt [IsWellOrder ι (· < ·)] (f : ι → E) (n : ι) : E := f n - ∑ i : Iio n, orthogonalProjection (𝕜 ∙ gramSchmidt f i) (f n) termination_by n decreasing_by exact mem_Iio.1 i.2 #align gram_schmidt gramSchmidt theorem gramSchmidt_def (f : ι → E) (n : ι) : gramSchmidt 𝕜 f n = f n - ∑ i ∈ Iio n, orthogonalProjection (𝕜 ∙ gramSchmidt 𝕜 f i) (f n) := by rw [← sum_attach, attach_eq_univ, gramSchmidt] #align gram_schmidt_def gramSchmidt_def theorem gramSchmidt_def' (f : ι → E) (n : ι) : f n = gramSchmidt 𝕜 f n + ∑ i ∈ Iio n, orthogonalProjection (𝕜 ∙ gramSchmidt 𝕜 f i) (f n) := by rw [gramSchmidt_def, sub_add_cancel] #align gram_schmidt_def' gramSchmidt_def' theorem gramSchmidt_def'' (f : ι → E) (n : ι) : f n = gramSchmidt 𝕜 f n + ∑ i ∈ Iio n, (⟪gramSchmidt 𝕜 f i, f n⟫ / (‖gramSchmidt 𝕜 f i‖ : 𝕜) ^ 2) • gramSchmidt 𝕜 f i := by convert gramSchmidt_def' 𝕜 f n rw [orthogonalProjection_singleton, RCLike.ofReal_pow] #align gram_schmidt_def'' gramSchmidt_def'' @[simp] theorem gramSchmidt_zero {ι : Type*} [LinearOrder ι] [LocallyFiniteOrder ι] [OrderBot ι] [IsWellOrder ι (· < ·)] (f : ι → E) : gramSchmidt 𝕜 f ⊥ = f ⊥ := by rw [gramSchmidt_def, Iio_eq_Ico, Finset.Ico_self, Finset.sum_empty, sub_zero] #align gram_schmidt_zero gramSchmidt_zero theorem gramSchmidt_orthogonal (f : ι → E) {a b : ι} (h₀ : a ≠ b) : ⟪gramSchmidt 𝕜 f a, gramSchmidt 𝕜 f b⟫ = 0 := by suffices ∀ a b : ι, a < b → ⟪gramSchmidt 𝕜 f a, gramSchmidt 𝕜 f b⟫ = 0 by cases' h₀.lt_or_lt with ha hb · exact this _ _ ha · rw [inner_eq_zero_symm] exact this _ _ hb clear h₀ a b intro a b h₀ revert a apply wellFounded_lt.induction b intro b ih a h₀ simp only [gramSchmidt_def 𝕜 f b, inner_sub_right, inner_sum, orthogonalProjection_singleton, inner_smul_right] rw [Finset.sum_eq_single_of_mem a (Finset.mem_Iio.mpr h₀)] · by_cases h : gramSchmidt 𝕜 f a = 0 · simp only [h, inner_zero_left, zero_div, zero_mul, sub_zero] · rw [RCLike.ofReal_pow, ← inner_self_eq_norm_sq_to_K, div_mul_cancel₀, sub_self] rwa [inner_self_ne_zero] intro i hi hia simp only [mul_eq_zero, div_eq_zero_iff, inner_self_eq_zero] right cases' hia.lt_or_lt with hia₁ hia₂ · rw [inner_eq_zero_symm] exact ih a h₀ i hia₁ · exact ih i (mem_Iio.1 hi) a hia₂ #align gram_schmidt_orthogonal gramSchmidt_orthogonal theorem gramSchmidt_pairwise_orthogonal (f : ι → E) : Pairwise fun a b => ⟪gramSchmidt 𝕜 f a, gramSchmidt 𝕜 f b⟫ = 0 := fun _ _ => gramSchmidt_orthogonal 𝕜 f #align gram_schmidt_pairwise_orthogonal gramSchmidt_pairwise_orthogonal theorem gramSchmidt_inv_triangular (v : ι → E) {i j : ι} (hij : i < j) : ⟪gramSchmidt 𝕜 v j, v i⟫ = 0 := by rw [gramSchmidt_def'' 𝕜 v] simp only [inner_add_right, inner_sum, inner_smul_right] set b : ι → E := gramSchmidt 𝕜 v convert zero_add (0 : 𝕜) · exact gramSchmidt_orthogonal 𝕜 v hij.ne' apply Finset.sum_eq_zero rintro k hki' have hki : k < i := by simpa using hki' have : ⟪b j, b k⟫ = 0 := gramSchmidt_orthogonal 𝕜 v (hki.trans hij).ne' simp [this] #align gram_schmidt_inv_triangular gramSchmidt_inv_triangular open Submodule Set Order
Mathlib/Analysis/InnerProductSpace/GramSchmidtOrtho.lean
133
139
theorem mem_span_gramSchmidt (f : ι → E) {i j : ι} (hij : i ≤ j) : f i ∈ span 𝕜 (gramSchmidt 𝕜 f '' Set.Iic j) := by rw [gramSchmidt_def' 𝕜 f i]
rw [gramSchmidt_def' 𝕜 f i] simp_rw [orthogonalProjection_singleton] exact Submodule.add_mem _ (subset_span <| mem_image_of_mem _ hij) (Submodule.sum_mem _ fun k hk => smul_mem (span 𝕜 (gramSchmidt 𝕜 f '' Set.Iic j)) _ <| subset_span <| mem_image_of_mem (gramSchmidt 𝕜 f) <| (Finset.mem_Iio.1 hk).le.trans hij)
true
import Mathlib.Data.Real.Irrational import Mathlib.Data.Rat.Encodable import Mathlib.Topology.GDelta #align_import topology.instances.irrational from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982" open Set Filter Metric open Filter Topology protected theorem IsGδ.setOf_irrational : IsGδ { x | Irrational x } := (countable_range _).isGδ_compl set_option linter.uppercaseLean3 false in #align is_Gδ_irrational IsGδ.setOf_irrational @[deprecated (since := "2024-02-15")] alias isGδ_irrational := IsGδ.setOf_irrational
Mathlib/Topology/Instances/Irrational.lean
45
51
theorem dense_irrational : Dense { x : ℝ | Irrational x } := by refine Real.isTopologicalBasis_Ioo_rat.dense_iff.2 ?_
refine Real.isTopologicalBasis_Ioo_rat.dense_iff.2 ?_ simp only [gt_iff_lt, Rat.cast_lt, not_lt, ge_iff_le, Rat.cast_le, mem_iUnion, mem_singleton_iff, exists_prop, forall_exists_index, and_imp] rintro _ a b hlt rfl _ rw [inter_comm] exact exists_irrational_btwn (Rat.cast_lt.2 hlt)
true
import Mathlib.Data.Multiset.Basic #align_import data.multiset.range from "leanprover-community/mathlib"@"0a0ec35061ed9960bf0e7ffb0335f44447b58977" open List Nat namespace Multiset -- range def range (n : ℕ) : Multiset ℕ := List.range n #align multiset.range Multiset.range theorem coe_range (n : ℕ) : ↑(List.range n) = range n := rfl #align multiset.coe_range Multiset.coe_range @[simp] theorem range_zero : range 0 = 0 := rfl #align multiset.range_zero Multiset.range_zero @[simp]
Mathlib/Data/Multiset/Range.lean
34
35
theorem range_succ (n : ℕ) : range (succ n) = n ::ₘ range n := by
rw [range, List.range_succ, ← coe_add, add_comm]; rfl
true
import Mathlib.Analysis.Convex.Function import Mathlib.Analysis.Convex.StrictConvexSpace import Mathlib.MeasureTheory.Function.AEEqOfIntegral import Mathlib.MeasureTheory.Integral.Average #align_import analysis.convex.integral from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982" open 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 : Measure α} {s : Set E} {t : Set α} {f : α → E} {g : E → ℝ} {C : ℝ} theorem Convex.integral_mem [IsProbabilityMeasure μ] (hs : Convex ℝ s) (hsc : IsClosed s) (hf : ∀ᵐ x ∂μ, f x ∈ s) (hfi : Integrable f μ) : (∫ x, f x ∂μ) ∈ s := by borelize E rcases hfi.aestronglyMeasurable with ⟨g, hgm, hfg⟩ haveI : SeparableSpace (range g ∩ s : Set E) := (hgm.isSeparable_range.mono inter_subset_left).separableSpace obtain ⟨y₀, h₀⟩ : (range g ∩ s).Nonempty := by rcases (hf.and hfg).exists with ⟨x₀, h₀⟩ exact ⟨f x₀, by simp only [h₀.2, mem_range_self], h₀.1⟩ rw [integral_congr_ae hfg]; rw [integrable_congr hfg] at hfi have hg : ∀ᵐ x ∂μ, g x ∈ closure (range g ∩ s) := by filter_upwards [hfg.rw (fun _ y => y ∈ s) hf] with x hx apply subset_closure exact ⟨mem_range_self _, hx⟩ set G : ℕ → SimpleFunc α E := SimpleFunc.approxOn _ hgm.measurable (range g ∩ s) y₀ h₀ have : Tendsto (fun n => (G n).integral μ) atTop (𝓝 <| ∫ x, g x ∂μ) := tendsto_integral_approxOn_of_measurable hfi _ hg _ (integrable_const _) refine hsc.mem_of_tendsto this (eventually_of_forall fun n => hs.sum_mem ?_ ?_ ?_) · exact fun _ _ => ENNReal.toReal_nonneg · rw [← ENNReal.toReal_sum, (G n).sum_range_measure_preimage_singleton, measure_univ, ENNReal.one_toReal] exact fun _ _ => measure_ne_top _ _ · simp only [SimpleFunc.mem_range, forall_mem_range] intro x apply (range g).inter_subset_right exact SimpleFunc.approxOn_mem hgm.measurable h₀ _ _ #align convex.integral_mem Convex.integral_mem theorem Convex.average_mem [IsFiniteMeasure μ] [NeZero μ] (hs : Convex ℝ s) (hsc : IsClosed s) (hfs : ∀ᵐ x ∂μ, f x ∈ s) (hfi : Integrable f μ) : (⨍ x, f x ∂μ) ∈ s := by refine hs.integral_mem hsc (ae_mono' ?_ hfs) hfi.to_average exact AbsolutelyContinuous.smul (refl _) _ #align convex.average_mem Convex.average_mem theorem Convex.set_average_mem (hs : Convex ℝ s) (hsc : IsClosed s) (h0 : μ t ≠ 0) (ht : μ t ≠ ∞) (hfs : ∀ᵐ x ∂μ.restrict t, f x ∈ s) (hfi : IntegrableOn f t μ) : (⨍ x in t, f x ∂μ) ∈ s := have := Fact.mk ht.lt_top have := NeZero.mk h0 hs.average_mem hsc hfs hfi #align convex.set_average_mem Convex.set_average_mem theorem Convex.set_average_mem_closure (hs : Convex ℝ s) (h0 : μ t ≠ 0) (ht : μ t ≠ ∞) (hfs : ∀ᵐ x ∂μ.restrict t, f x ∈ s) (hfi : IntegrableOn f t μ) : (⨍ x in t, f x ∂μ) ∈ closure s := hs.closure.set_average_mem isClosed_closure h0 ht (hfs.mono fun _ hx => subset_closure hx) hfi #align convex.set_average_mem_closure Convex.set_average_mem_closure
Mathlib/Analysis/Convex/Integral.lean
112
119
theorem ConvexOn.average_mem_epigraph [IsFiniteMeasure μ] [NeZero μ] (hg : ConvexOn ℝ s g) (hgc : ContinuousOn g s) (hsc : IsClosed s) (hfs : ∀ᵐ x ∂μ, f x ∈ s) (hfi : Integrable f μ) (hgi : Integrable (g ∘ f) μ) : (⨍ x, f x ∂μ, ⨍ x, g (f x) ∂μ) ∈ {p : E × ℝ | p.1 ∈ s ∧ g p.1 ≤ p.2} := by have ht_mem : ∀ᵐ x ∂μ, (f x, g (f x)) ∈ {p : E × ℝ | p.1 ∈ s ∧ g p.1 ≤ p.2} :=
have ht_mem : ∀ᵐ x ∂μ, (f x, g (f x)) ∈ {p : E × ℝ | p.1 ∈ s ∧ g p.1 ≤ p.2} := hfs.mono fun x hx => ⟨hx, le_rfl⟩ exact average_pair hfi hgi ▸ hg.convex_epigraph.average_mem (hsc.epigraph hgc) ht_mem (hfi.prod_mk hgi)
true
import Mathlib.Analysis.Normed.Group.Pointwise import Mathlib.Analysis.NormedSpace.Real #align_import analysis.normed_space.pointwise from "leanprover-community/mathlib"@"bc91ed7093bf098d253401e69df601fc33dde156" open Metric Set open Pointwise Topology variable {𝕜 E : Type*} variable [NormedField 𝕜] section SeminormedAddCommGroup variable [SeminormedAddCommGroup E] [NormedSpace 𝕜 E]
Mathlib/Analysis/NormedSpace/Pointwise.lean
84
88
theorem smul_ball {c : 𝕜} (hc : c ≠ 0) (x : E) (r : ℝ) : c • ball x r = ball (c • x) (‖c‖ * r) := by ext y
ext y rw [mem_smul_set_iff_inv_smul_mem₀ hc] conv_lhs => rw [← inv_smul_smul₀ hc x] simp [← div_eq_inv_mul, div_lt_iff (norm_pos_iff.2 hc), mul_comm _ r, dist_smul₀]
true
import Mathlib.Algebra.GroupWithZero.Divisibility import Mathlib.Algebra.Order.Ring.Nat import Mathlib.Tactic.NthRewrite #align_import data.nat.gcd.basic from "leanprover-community/mathlib"@"e8638a0fcaf73e4500469f368ef9494e495099b3" namespace Nat theorem gcd_greatest {a b d : ℕ} (hda : d ∣ a) (hdb : d ∣ b) (hd : ∀ e : ℕ, e ∣ a → e ∣ b → e ∣ d) : d = a.gcd b := (dvd_antisymm (hd _ (gcd_dvd_left a b) (gcd_dvd_right a b)) (dvd_gcd hda hdb)).symm #align nat.gcd_greatest Nat.gcd_greatest @[simp] theorem gcd_add_mul_right_right (m n k : ℕ) : gcd m (n + k * m) = gcd m n := by simp [gcd_rec m (n + k * m), gcd_rec m n] #align nat.gcd_add_mul_right_right Nat.gcd_add_mul_right_right @[simp] theorem gcd_add_mul_left_right (m n k : ℕ) : gcd m (n + m * k) = gcd m n := by simp [gcd_rec m (n + m * k), gcd_rec m n] #align nat.gcd_add_mul_left_right Nat.gcd_add_mul_left_right @[simp] theorem gcd_mul_right_add_right (m n k : ℕ) : gcd m (k * m + n) = gcd m n := by simp [add_comm _ n] #align nat.gcd_mul_right_add_right Nat.gcd_mul_right_add_right @[simp] theorem gcd_mul_left_add_right (m n k : ℕ) : gcd m (m * k + n) = gcd m n := by simp [add_comm _ n] #align nat.gcd_mul_left_add_right Nat.gcd_mul_left_add_right @[simp]
Mathlib/Data/Nat/GCD/Basic.lean
53
54
theorem gcd_add_mul_right_left (m n k : ℕ) : gcd (m + k * n) n = gcd m n := by
rw [gcd_comm, gcd_add_mul_right_right, gcd_comm]
true
import Batteries.Data.List.Lemmas namespace List universe u v variable {α : Type u} {β : Type v} @[simp] theorem eraseIdx_zero (l : List α) : eraseIdx l 0 = tail l := by cases l <;> rfl theorem eraseIdx_eq_take_drop_succ : ∀ (l : List α) (i : Nat), l.eraseIdx i = l.take i ++ l.drop (i + 1) | nil, _ => by simp | a::l, 0 => by simp | a::l, i + 1 => by simp [eraseIdx_eq_take_drop_succ l i] theorem eraseIdx_sublist : ∀ (l : List α) (k : Nat), eraseIdx l k <+ l | [], _ => by simp | a::l, 0 => by simp | a::l, k + 1 => by simp [eraseIdx_sublist l k] theorem eraseIdx_subset (l : List α) (k : Nat) : eraseIdx l k ⊆ l := (eraseIdx_sublist l k).subset @[simp] theorem eraseIdx_eq_self : ∀ {l : List α} {k : Nat}, eraseIdx l k = l ↔ length l ≤ k | [], _ => by simp | a::l, 0 => by simp [(cons_ne_self _ _).symm] | a::l, k + 1 => by simp [eraseIdx_eq_self] alias ⟨_, eraseIdx_of_length_le⟩ := eraseIdx_eq_self
.lake/packages/batteries/Batteries/Data/List/EraseIdx.lean
43
47
theorem eraseIdx_append_of_lt_length {l : List α} {k : Nat} (hk : k < length l) (l' : List α) : eraseIdx (l ++ l') k = eraseIdx l k ++ l' := by rw [eraseIdx_eq_take_drop_succ, take_append_of_le_length, drop_append_of_le_length,
rw [eraseIdx_eq_take_drop_succ, take_append_of_le_length, drop_append_of_le_length, eraseIdx_eq_take_drop_succ, append_assoc] all_goals omega
true
import Mathlib.Init.Algebra.Classes import Mathlib.Logic.Nontrivial.Basic import Mathlib.Order.BoundedOrder import Mathlib.Data.Option.NAry import Mathlib.Tactic.Lift import Mathlib.Data.Option.Basic #align_import order.with_bot from "leanprover-community/mathlib"@"0111834459f5d7400215223ea95ae38a1265a907" variable {α β γ δ : Type*} def WithBot (α : Type*) := Option α #align with_bot WithBot namespace WithBot variable {a b : α} instance [Repr α] : Repr (WithBot α) := ⟨fun o _ => match o with | none => "⊥" | some a => "↑" ++ repr a⟩ @[coe, match_pattern] def some : α → WithBot α := Option.some -- Porting note: changed this from `CoeTC` to `Coe` but I am not 100% confident that's correct. instance coe : Coe α (WithBot α) := ⟨some⟩ instance bot : Bot (WithBot α) := ⟨none⟩ instance inhabited : Inhabited (WithBot α) := ⟨⊥⟩ instance nontrivial [Nonempty α] : Nontrivial (WithBot α) := Option.nontrivial open Function theorem coe_injective : Injective ((↑) : α → WithBot α) := Option.some_injective _ #align with_bot.coe_injective WithBot.coe_injective @[simp, norm_cast] theorem coe_inj : (a : WithBot α) = b ↔ a = b := Option.some_inj #align with_bot.coe_inj WithBot.coe_inj protected theorem «forall» {p : WithBot α → Prop} : (∀ x, p x) ↔ p ⊥ ∧ ∀ x : α, p x := Option.forall #align with_bot.forall WithBot.forall protected theorem «exists» {p : WithBot α → Prop} : (∃ x, p x) ↔ p ⊥ ∨ ∃ x : α, p x := Option.exists #align with_bot.exists WithBot.exists theorem none_eq_bot : (none : WithBot α) = (⊥ : WithBot α) := rfl #align with_bot.none_eq_bot WithBot.none_eq_bot theorem some_eq_coe (a : α) : (Option.some a : WithBot α) = (↑a : WithBot α) := rfl #align with_bot.some_eq_coe WithBot.some_eq_coe @[simp] theorem bot_ne_coe : ⊥ ≠ (a : WithBot α) := nofun #align with_bot.bot_ne_coe WithBot.bot_ne_coe @[simp] theorem coe_ne_bot : (a : WithBot α) ≠ ⊥ := nofun #align with_bot.coe_ne_bot WithBot.coe_ne_bot @[elab_as_elim, induction_eliminator, cases_eliminator] def recBotCoe {C : WithBot α → Sort*} (bot : C ⊥) (coe : ∀ a : α, C a) : ∀ n : WithBot α, C n | ⊥ => bot | (a : α) => coe a #align with_bot.rec_bot_coe WithBot.recBotCoe @[simp] theorem recBotCoe_bot {C : WithBot α → Sort*} (d : C ⊥) (f : ∀ a : α, C a) : @recBotCoe _ C d f ⊥ = d := rfl #align with_bot.rec_bot_coe_bot WithBot.recBotCoe_bot @[simp] theorem recBotCoe_coe {C : WithBot α → Sort*} (d : C ⊥) (f : ∀ a : α, C a) (x : α) : @recBotCoe _ C d f ↑x = f x := rfl #align with_bot.rec_bot_coe_coe WithBot.recBotCoe_coe def unbot' (d : α) (x : WithBot α) : α := recBotCoe d id x #align with_bot.unbot' WithBot.unbot' @[simp] theorem unbot'_bot {α} (d : α) : unbot' d ⊥ = d := rfl #align with_bot.unbot'_bot WithBot.unbot'_bot @[simp] theorem unbot'_coe {α} (d x : α) : unbot' d x = x := rfl #align with_bot.unbot'_coe WithBot.unbot'_coe theorem coe_eq_coe : (a : WithBot α) = b ↔ a = b := coe_inj #align with_bot.coe_eq_coe WithBot.coe_eq_coe theorem unbot'_eq_iff {d y : α} {x : WithBot α} : unbot' d x = y ↔ x = y ∨ x = ⊥ ∧ y = d := by induction x <;> simp [@eq_comm _ d] #align with_bot.unbot'_eq_iff WithBot.unbot'_eq_iff @[simp] theorem unbot'_eq_self_iff {d : α} {x : WithBot α} : unbot' d x = d ↔ x = d ∨ x = ⊥ := by simp [unbot'_eq_iff] #align with_bot.unbot'_eq_self_iff WithBot.unbot'_eq_self_iff
Mathlib/Order/WithBot.lean
143
145
theorem unbot'_eq_unbot'_iff {d : α} {x y : WithBot α} : unbot' d x = unbot' d y ↔ x = y ∨ x = d ∧ y = ⊥ ∨ x = ⊥ ∧ y = d := by
induction y <;> simp [unbot'_eq_iff, or_comm]
true
import Mathlib.LinearAlgebra.CliffordAlgebra.Fold import Mathlib.LinearAlgebra.ExteriorAlgebra.Basic #align_import linear_algebra.exterior_algebra.of_alternating from "leanprover-community/mathlib"@"ce11c3c2a285bbe6937e26d9792fda4e51f3fe1a" variable {R M N N' : Type*} variable [CommRing R] [AddCommGroup M] [AddCommGroup N] [AddCommGroup N'] variable [Module R M] [Module R N] [Module R N'] -- This instance can't be found where it's needed if we don't remind lean that it exists. instance AlternatingMap.instModuleAddCommGroup {ι : Type*} : Module R (M [⋀^ι]→ₗ[R] N) := by infer_instance #align alternating_map.module_add_comm_group AlternatingMap.instModuleAddCommGroup namespace ExteriorAlgebra open CliffordAlgebra hiding ι def liftAlternating : (∀ i, M [⋀^Fin i]→ₗ[R] N) →ₗ[R] ExteriorAlgebra R M →ₗ[R] N := by suffices (∀ i, M [⋀^Fin i]→ₗ[R] N) →ₗ[R] ExteriorAlgebra R M →ₗ[R] ∀ i, M [⋀^Fin i]→ₗ[R] N by refine LinearMap.compr₂ this ?_ refine (LinearEquiv.toLinearMap ?_).comp (LinearMap.proj 0) exact AlternatingMap.constLinearEquivOfIsEmpty.symm refine CliffordAlgebra.foldl _ ?_ ?_ · refine LinearMap.mk₂ R (fun m f i => (f i.succ).curryLeft m) (fun m₁ m₂ f => ?_) (fun c m f => ?_) (fun m f₁ f₂ => ?_) fun c m f => ?_ all_goals ext i : 1 simp only [map_smul, map_add, Pi.add_apply, Pi.smul_apply, AlternatingMap.curryLeft_add, AlternatingMap.curryLeft_smul, map_add, map_smul, LinearMap.add_apply, LinearMap.smul_apply] · -- when applied twice with the same `m`, this recursive step produces 0 intro m x dsimp only [LinearMap.mk₂_apply, QuadraticForm.coeFn_zero, Pi.zero_apply] simp_rw [zero_smul] ext i : 1 exact AlternatingMap.curryLeft_same _ _ #align exterior_algebra.lift_alternating ExteriorAlgebra.liftAlternating @[simp] theorem liftAlternating_ι (f : ∀ i, M [⋀^Fin i]→ₗ[R] N) (m : M) : liftAlternating (R := R) (M := M) (N := N) f (ι R m) = f 1 ![m] := by dsimp [liftAlternating] rw [foldl_ι, LinearMap.mk₂_apply, AlternatingMap.curryLeft_apply_apply] congr -- Porting note: In Lean 3, `congr` could use the `[Subsingleton (Fin 0 → M)]` instance to finish -- the proof. Here, the instance can be synthesized but `congr` does not use it so the following -- line is provided. rw [Matrix.zero_empty] #align exterior_algebra.lift_alternating_ι ExteriorAlgebra.liftAlternating_ι theorem liftAlternating_ι_mul (f : ∀ i, M [⋀^Fin i]→ₗ[R] N) (m : M) (x : ExteriorAlgebra R M) : liftAlternating (R := R) (M := M) (N := N) f (ι R m * x) = liftAlternating (R := R) (M := M) (N := N) (fun i => (f i.succ).curryLeft m) x := by dsimp [liftAlternating] rw [foldl_mul, foldl_ι] rfl #align exterior_algebra.lift_alternating_ι_mul ExteriorAlgebra.liftAlternating_ι_mul @[simp]
Mathlib/LinearAlgebra/ExteriorAlgebra/OfAlternating.lean
89
92
theorem liftAlternating_one (f : ∀ i, M [⋀^Fin i]→ₗ[R] N) : liftAlternating (R := R) (M := M) (N := N) f (1 : ExteriorAlgebra R M) = f 0 0 := by dsimp [liftAlternating]
dsimp [liftAlternating] rw [foldl_one]
true
import Mathlib.RingTheory.Localization.FractionRing import Mathlib.Algebra.Polynomial.RingDivision #align_import field_theory.ratfunc from "leanprover-community/mathlib"@"bf9bbbcf0c1c1ead18280b0d010e417b10abb1b6" noncomputable section open scoped Classical open scoped nonZeroDivisors Polynomial universe u v variable (K : Type u) structure RatFunc [CommRing K] : Type u where ofFractionRing :: toFractionRing : FractionRing K[X] #align ratfunc RatFunc #align ratfunc.of_fraction_ring RatFunc.ofFractionRing #align ratfunc.to_fraction_ring RatFunc.toFractionRing namespace RatFunc section CommRing variable {K} variable [CommRing K] section Rec theorem ofFractionRing_injective : Function.Injective (ofFractionRing : _ → RatFunc K) := fun _ _ => ofFractionRing.inj #align ratfunc.of_fraction_ring_injective RatFunc.ofFractionRing_injective theorem toFractionRing_injective : Function.Injective (toFractionRing : _ → FractionRing K[X]) -- Porting note: the `xy` input was `rfl` and then there was no need for the `subst` | ⟨x⟩, ⟨y⟩, xy => by subst xy; rfl #align ratfunc.to_fraction_ring_injective RatFunc.toFractionRing_injective protected irreducible_def liftOn {P : Sort v} (x : RatFunc K) (f : K[X] → K[X] → P) (H : ∀ {p q p' q'} (_hq : q ∈ K[X]⁰) (_hq' : q' ∈ K[X]⁰), q' * p = q * p' → f p q = f p' q') : P := by refine Localization.liftOn (toFractionRing x) (fun p q => f p q) ?_ intros p p' q q' h exact H q.2 q'.2 (let ⟨⟨c, hc⟩, mul_eq⟩ := Localization.r_iff_exists.mp h mul_cancel_left_coe_nonZeroDivisors.mp mul_eq) -- Porting note: the definition above was as follows -- (-- Fix timeout by manipulating elaboration order -- fun p q => f p q) -- fun p p' q q' h => by -- exact H q.2 q'.2 -- (let ⟨⟨c, hc⟩, mul_eq⟩ := Localization.r_iff_exists.mp h -- mul_cancel_left_coe_nonZeroDivisors.mp mul_eq) #align ratfunc.lift_on RatFunc.liftOn theorem liftOn_ofFractionRing_mk {P : Sort v} (n : K[X]) (d : K[X]⁰) (f : K[X] → K[X] → P) (H : ∀ {p q p' q'} (_hq : q ∈ K[X]⁰) (_hq' : q' ∈ K[X]⁰), q' * p = q * p' → f p q = f p' q') : RatFunc.liftOn (ofFractionRing (Localization.mk n d)) f @H = f n d := by rw [RatFunc.liftOn] exact Localization.liftOn_mk _ _ _ _ #align ratfunc.lift_on_of_fraction_ring_mk RatFunc.liftOn_ofFractionRing_mk theorem liftOn_condition_of_liftOn'_condition {P : Sort v} {f : K[X] → K[X] → P} (H : ∀ {p q a} (hq : q ≠ 0) (_ha : a ≠ 0), f (a * p) (a * q) = f p q) ⦃p q p' q' : K[X]⦄ (hq : q ≠ 0) (hq' : q' ≠ 0) (h : q' * p = q * p') : f p q = f p' q' := calc f p q = f (q' * p) (q' * q) := (H hq hq').symm _ = f (q * p') (q * q') := by rw [h, mul_comm q'] _ = f p' q' := H hq' hq #align ratfunc.lift_on_condition_of_lift_on'_condition RatFunc.liftOn_condition_of_liftOn'_condition section IsDomain variable [IsDomain K] protected irreducible_def mk (p q : K[X]) : RatFunc K := ofFractionRing (algebraMap _ _ p / algebraMap _ _ q) #align ratfunc.mk RatFunc.mk
Mathlib/FieldTheory/RatFunc/Defs.lean
154
155
theorem mk_eq_div' (p q : K[X]) : RatFunc.mk p q = ofFractionRing (algebraMap _ _ p / algebraMap _ _ q) := by
rw [RatFunc.mk]
true
import Mathlib.Algebra.Algebra.Hom import Mathlib.RingTheory.Ideal.Quotient #align_import algebra.ring_quot from "leanprover-community/mathlib"@"e5820f6c8fcf1b75bcd7738ae4da1c5896191f72" universe uR uS uT uA u₄ variable {R : Type uR} [Semiring R] variable {S : Type uS} [CommSemiring S] variable {T : Type uT} variable {A : Type uA} [Semiring A] [Algebra S A] namespace RingQuot inductive Rel (r : R → R → Prop) : R → R → Prop | of ⦃x y : R⦄ (h : r x y) : Rel r x y | add_left ⦃a b c⦄ : Rel r a b → Rel r (a + c) (b + c) | mul_left ⦃a b c⦄ : Rel r a b → Rel r (a * c) (b * c) | mul_right ⦃a b c⦄ : Rel r b c → Rel r (a * b) (a * c) #align ring_quot.rel RingQuot.Rel theorem Rel.add_right {r : R → R → Prop} ⦃a b c : R⦄ (h : Rel r b c) : Rel r (a + b) (a + c) := by rw [add_comm a b, add_comm a c] exact Rel.add_left h #align ring_quot.rel.add_right RingQuot.Rel.add_right theorem Rel.neg {R : Type uR} [Ring R] {r : R → R → Prop} ⦃a b : R⦄ (h : Rel r a b) : Rel r (-a) (-b) := by simp only [neg_eq_neg_one_mul a, neg_eq_neg_one_mul b, Rel.mul_right h] #align ring_quot.rel.neg RingQuot.Rel.neg theorem Rel.sub_left {R : Type uR} [Ring R] {r : R → R → Prop} ⦃a b c : R⦄ (h : Rel r a b) : Rel r (a - c) (b - c) := by simp only [sub_eq_add_neg, h.add_left] #align ring_quot.rel.sub_left RingQuot.Rel.sub_left theorem Rel.sub_right {R : Type uR} [Ring R] {r : R → R → Prop} ⦃a b c : R⦄ (h : Rel r b c) : Rel r (a - b) (a - c) := by simp only [sub_eq_add_neg, h.neg.add_right] #align ring_quot.rel.sub_right RingQuot.Rel.sub_right
Mathlib/Algebra/RingQuot.lean
79
80
theorem Rel.smul {r : A → A → Prop} (k : S) ⦃a b : A⦄ (h : Rel r a b) : Rel r (k • a) (k • b) := by
simp only [Algebra.smul_def, Rel.mul_right h]
true
import Mathlib.Data.ENat.Lattice import Mathlib.Order.OrderIsoNat import Mathlib.Tactic.TFAE #align_import order.height from "leanprover-community/mathlib"@"bf27744463e9620ca4e4ebe951fe83530ae6949b" open List hiding le_antisymm open OrderDual universe u v variable {α β : Type*} namespace Set section LT variable [LT α] [LT β] (s t : Set α) def subchain : Set (List α) := { l | l.Chain' (· < ·) ∧ ∀ i ∈ l, i ∈ s } #align set.subchain Set.subchain @[simp] -- porting note: new `simp` theorem nil_mem_subchain : [] ∈ s.subchain := ⟨trivial, fun _ ↦ nofun⟩ #align set.nil_mem_subchain Set.nil_mem_subchain variable {s} {l : List α} {a : α} theorem cons_mem_subchain_iff : (a::l) ∈ s.subchain ↔ a ∈ s ∧ l ∈ s.subchain ∧ ∀ b ∈ l.head?, a < b := by simp only [subchain, mem_setOf_eq, forall_mem_cons, chain'_cons', and_left_comm, and_comm, and_assoc] #align set.cons_mem_subchain_iff Set.cons_mem_subchain_iff @[simp] -- Porting note (#10756): new lemma + `simp` theorem singleton_mem_subchain_iff : [a] ∈ s.subchain ↔ a ∈ s := by simp [cons_mem_subchain_iff] instance : Nonempty s.subchain := ⟨⟨[], s.nil_mem_subchain⟩⟩ variable (s) noncomputable def chainHeight : ℕ∞ := ⨆ l ∈ s.subchain, length l #align set.chain_height Set.chainHeight theorem chainHeight_eq_iSup_subtype : s.chainHeight = ⨆ l : s.subchain, ↑l.1.length := iSup_subtype' #align set.chain_height_eq_supr_subtype Set.chainHeight_eq_iSup_subtype theorem exists_chain_of_le_chainHeight {n : ℕ} (hn : ↑n ≤ s.chainHeight) : ∃ l ∈ s.subchain, length l = n := by rcases (le_top : s.chainHeight ≤ ⊤).eq_or_lt with ha | ha <;> rw [chainHeight_eq_iSup_subtype] at ha · obtain ⟨_, ⟨⟨l, h₁, h₂⟩, rfl⟩, h₃⟩ := not_bddAbove_iff'.mp (WithTop.iSup_coe_eq_top.1 ha) n exact ⟨l.take n, ⟨h₁.take _, fun x h ↦ h₂ _ <| take_subset _ _ h⟩, (l.length_take n).trans <| min_eq_left <| le_of_not_ge h₃⟩ · rw [ENat.iSup_coe_lt_top] at ha obtain ⟨⟨l, h₁, h₂⟩, e : l.length = _⟩ := Nat.sSup_mem (Set.range_nonempty _) ha refine ⟨l.take n, ⟨h₁.take _, fun x h ↦ h₂ _ <| take_subset _ _ h⟩, (l.length_take n).trans <| min_eq_left <| ?_⟩ rwa [e, ← Nat.cast_le (α := ℕ∞), sSup_range, ENat.coe_iSup ha, ← chainHeight_eq_iSup_subtype] #align set.exists_chain_of_le_chain_height Set.exists_chain_of_le_chainHeight theorem le_chainHeight_TFAE (n : ℕ) : TFAE [↑n ≤ s.chainHeight, ∃ l ∈ s.subchain, length l = n, ∃ l ∈ s.subchain, n ≤ length l] := by tfae_have 1 → 2; · exact s.exists_chain_of_le_chainHeight tfae_have 2 → 3; · rintro ⟨l, hls, he⟩; exact ⟨l, hls, he.ge⟩ tfae_have 3 → 1; · rintro ⟨l, hs, hn⟩; exact le_iSup₂_of_le l hs (WithTop.coe_le_coe.2 hn) tfae_finish #align set.le_chain_height_tfae Set.le_chainHeight_TFAE variable {s t} theorem le_chainHeight_iff {n : ℕ} : ↑n ≤ s.chainHeight ↔ ∃ l ∈ s.subchain, length l = n := (le_chainHeight_TFAE s n).out 0 1 #align set.le_chain_height_iff Set.le_chainHeight_iff theorem length_le_chainHeight_of_mem_subchain (hl : l ∈ s.subchain) : ↑l.length ≤ s.chainHeight := le_chainHeight_iff.mpr ⟨l, hl, rfl⟩ #align set.length_le_chain_height_of_mem_subchain Set.length_le_chainHeight_of_mem_subchain theorem chainHeight_eq_top_iff : s.chainHeight = ⊤ ↔ ∀ n, ∃ l ∈ s.subchain, length l = n := by refine ⟨fun h n ↦ le_chainHeight_iff.1 (le_top.trans_eq h.symm), fun h ↦ ?_⟩ contrapose! h; obtain ⟨n, hn⟩ := WithTop.ne_top_iff_exists.1 h exact ⟨n + 1, fun l hs ↦ (Nat.lt_succ_iff.2 <| Nat.cast_le.1 <| (length_le_chainHeight_of_mem_subchain hs).trans_eq hn.symm).ne⟩ #align set.chain_height_eq_top_iff Set.chainHeight_eq_top_iff @[simp]
Mathlib/Order/Height.lean
135
138
theorem one_le_chainHeight_iff : 1 ≤ s.chainHeight ↔ s.Nonempty := by rw [← Nat.cast_one, Set.le_chainHeight_iff]
rw [← Nat.cast_one, Set.le_chainHeight_iff] simp only [length_eq_one, @and_comm (_ ∈ _), @eq_comm _ _ [_], exists_exists_eq_and, singleton_mem_subchain_iff, Set.Nonempty]
true
import Mathlib.SetTheory.Cardinal.Finite #align_import data.finite.card from "leanprover-community/mathlib"@"3ff3f2d6a3118b8711063de7111a0d77a53219a8" noncomputable section open scoped Classical variable {α β γ : Type*} def Finite.equivFin (α : Type*) [Finite α] : α ≃ Fin (Nat.card α) := by have := (Finite.exists_equiv_fin α).choose_spec.some rwa [Nat.card_eq_of_equiv_fin this] #align finite.equiv_fin Finite.equivFin def Finite.equivFinOfCardEq [Finite α] {n : ℕ} (h : Nat.card α = n) : α ≃ Fin n := by subst h apply Finite.equivFin #align finite.equiv_fin_of_card_eq Finite.equivFinOfCardEq theorem Nat.card_eq (α : Type*) : Nat.card α = if h : Finite α then @Fintype.card α (Fintype.ofFinite α) else 0 := by cases finite_or_infinite α · letI := Fintype.ofFinite α simp only [*, Nat.card_eq_fintype_card, dif_pos] · simp only [*, card_eq_zero_of_infinite, not_finite_iff_infinite.mpr, dite_false] #align nat.card_eq Nat.card_eq theorem Finite.card_pos_iff [Finite α] : 0 < Nat.card α ↔ Nonempty α := by haveI := Fintype.ofFinite α rw [Nat.card_eq_fintype_card, Fintype.card_pos_iff] #align finite.card_pos_iff Finite.card_pos_iff theorem Finite.card_pos [Finite α] [h : Nonempty α] : 0 < Nat.card α := Finite.card_pos_iff.mpr h #align finite.card_pos Finite.card_pos namespace Finite theorem cast_card_eq_mk {α : Type*} [Finite α] : ↑(Nat.card α) = Cardinal.mk α := Cardinal.cast_toNat_of_lt_aleph0 (Cardinal.lt_aleph0_of_finite α) #align finite.cast_card_eq_mk Finite.cast_card_eq_mk theorem card_eq [Finite α] [Finite β] : Nat.card α = Nat.card β ↔ Nonempty (α ≃ β) := by haveI := Fintype.ofFinite α haveI := Fintype.ofFinite β simp only [Nat.card_eq_fintype_card, Fintype.card_eq] #align finite.card_eq Finite.card_eq
Mathlib/Data/Finite/Card.lean
78
80
theorem card_le_one_iff_subsingleton [Finite α] : Nat.card α ≤ 1 ↔ Subsingleton α := by haveI := Fintype.ofFinite α
haveI := Fintype.ofFinite α simp only [Nat.card_eq_fintype_card, Fintype.card_le_one_iff_subsingleton]
true
import Mathlib.Algebra.Polynomial.Degree.Definitions import Mathlib.Algebra.Polynomial.Eval import Mathlib.Algebra.Polynomial.Monic import Mathlib.Algebra.Polynomial.RingDivision import Mathlib.Tactic.Abel #align_import ring_theory.polynomial.pochhammer from "leanprover-community/mathlib"@"53b216bcc1146df1c4a0a86877890ea9f1f01589" universe u v open Polynomial open Polynomial section Semiring variable (S : Type u) [Semiring S] noncomputable def ascPochhammer : ℕ → S[X] | 0 => 1 | n + 1 => X * (ascPochhammer n).comp (X + 1) #align pochhammer ascPochhammer @[simp] theorem ascPochhammer_zero : ascPochhammer S 0 = 1 := rfl #align pochhammer_zero ascPochhammer_zero @[simp] theorem ascPochhammer_one : ascPochhammer S 1 = X := by simp [ascPochhammer] #align pochhammer_one ascPochhammer_one theorem ascPochhammer_succ_left (n : ℕ) : ascPochhammer S (n + 1) = X * (ascPochhammer S n).comp (X + 1) := by rw [ascPochhammer] #align pochhammer_succ_left ascPochhammer_succ_left theorem monic_ascPochhammer (n : ℕ) [Nontrivial S] [NoZeroDivisors S] : Monic <| ascPochhammer S n := by induction' n with n hn · simp · have : leadingCoeff (X + 1 : S[X]) = 1 := leadingCoeff_X_add_C 1 rw [ascPochhammer_succ_left, Monic.def, leadingCoeff_mul, leadingCoeff_comp (ne_zero_of_eq_one <| natDegree_X_add_C 1 : natDegree (X + 1) ≠ 0), hn, monic_X, one_mul, one_mul, this, one_pow] section variable {S} {T : Type v} [Semiring T] @[simp] theorem ascPochhammer_map (f : S →+* T) (n : ℕ) : (ascPochhammer S n).map f = ascPochhammer T n := by induction' n with n ih · simp · simp [ih, ascPochhammer_succ_left, map_comp] #align pochhammer_map ascPochhammer_map theorem ascPochhammer_eval₂ (f : S →+* T) (n : ℕ) (t : T) : (ascPochhammer T n).eval t = (ascPochhammer S n).eval₂ f t := by rw [← ascPochhammer_map f] exact eval_map f t theorem ascPochhammer_eval_comp {R : Type*} [CommSemiring R] (n : ℕ) (p : R[X]) [Algebra R S] (x : S) : ((ascPochhammer S n).comp (p.map (algebraMap R S))).eval x = (ascPochhammer S n).eval (p.eval₂ (algebraMap R S) x) := by rw [ascPochhammer_eval₂ (algebraMap R S), ← eval₂_comp', ← ascPochhammer_map (algebraMap R S), ← map_comp, eval_map] end @[simp, norm_cast]
Mathlib/RingTheory/Polynomial/Pochhammer.lean
104
107
theorem ascPochhammer_eval_cast (n k : ℕ) : (((ascPochhammer ℕ n).eval k : ℕ) : S) = ((ascPochhammer S n).eval k : S) := by rw [← ascPochhammer_map (algebraMap ℕ S), eval_map, ← eq_natCast (algebraMap ℕ S),
rw [← ascPochhammer_map (algebraMap ℕ S), eval_map, ← eq_natCast (algebraMap ℕ S), eval₂_at_natCast,Nat.cast_id]
true
import Mathlib.Analysis.Complex.Circle import Mathlib.Analysis.NormedSpace.BallAction #align_import analysis.complex.unit_disc.basic from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a" open Set Function Metric noncomputable section local notation "conj'" => starRingEnd ℂ namespace Complex def UnitDisc : Type := ball (0 : ℂ) 1 deriving TopologicalSpace #align complex.unit_disc Complex.UnitDisc @[inherit_doc] scoped[UnitDisc] notation "𝔻" => Complex.UnitDisc open UnitDisc namespace UnitDisc instance instCommSemigroup : CommSemigroup UnitDisc := by unfold UnitDisc; infer_instance instance instHasDistribNeg : HasDistribNeg UnitDisc := by unfold UnitDisc; infer_instance instance instCoe : Coe UnitDisc ℂ := ⟨Subtype.val⟩ theorem coe_injective : Injective ((↑) : 𝔻 → ℂ) := Subtype.coe_injective #align complex.unit_disc.coe_injective Complex.UnitDisc.coe_injective theorem abs_lt_one (z : 𝔻) : abs (z : ℂ) < 1 := mem_ball_zero_iff.1 z.2 #align complex.unit_disc.abs_lt_one Complex.UnitDisc.abs_lt_one theorem abs_ne_one (z : 𝔻) : abs (z : ℂ) ≠ 1 := z.abs_lt_one.ne #align complex.unit_disc.abs_ne_one Complex.UnitDisc.abs_ne_one
Mathlib/Analysis/Complex/UnitDisc/Basic.lean
53
55
theorem normSq_lt_one (z : 𝔻) : normSq z < 1 := by convert (Real.sqrt_lt' one_pos).1 z.abs_lt_one
convert (Real.sqrt_lt' one_pos).1 z.abs_lt_one exact (one_pow 2).symm
true
import Mathlib.MeasureTheory.MeasurableSpace.Basic import Mathlib.Data.Set.MemPartition import Mathlib.Order.Filter.CountableSeparatingOn open Set MeasureTheory namespace MeasurableSpace variable {α β : Type*} class CountablyGenerated (α : Type*) [m : MeasurableSpace α] : Prop where isCountablyGenerated : ∃ b : Set (Set α), b.Countable ∧ m = generateFrom b #align measurable_space.countably_generated MeasurableSpace.CountablyGenerated def countableGeneratingSet (α : Type*) [MeasurableSpace α] [h : CountablyGenerated α] : Set (Set α) := insert ∅ h.isCountablyGenerated.choose lemma countable_countableGeneratingSet [MeasurableSpace α] [h : CountablyGenerated α] : Set.Countable (countableGeneratingSet α) := Countable.insert _ h.isCountablyGenerated.choose_spec.1 lemma generateFrom_countableGeneratingSet [m : MeasurableSpace α] [h : CountablyGenerated α] : generateFrom (countableGeneratingSet α) = m := (generateFrom_insert_empty _).trans <| h.isCountablyGenerated.choose_spec.2.symm lemma empty_mem_countableGeneratingSet [MeasurableSpace α] [CountablyGenerated α] : ∅ ∈ countableGeneratingSet α := mem_insert _ _ lemma nonempty_countableGeneratingSet [MeasurableSpace α] [CountablyGenerated α] : Set.Nonempty (countableGeneratingSet α) := ⟨∅, mem_insert _ _⟩ lemma measurableSet_countableGeneratingSet [MeasurableSpace α] [CountablyGenerated α] {s : Set α} (hs : s ∈ countableGeneratingSet α) : MeasurableSet s := by rw [← generateFrom_countableGeneratingSet (α := α)] exact measurableSet_generateFrom hs def natGeneratingSequence (α : Type*) [MeasurableSpace α] [CountablyGenerated α] : ℕ → (Set α) := enumerateCountable (countable_countableGeneratingSet (α := α)) ∅ lemma generateFrom_natGeneratingSequence (α : Type*) [m : MeasurableSpace α] [CountablyGenerated α] : generateFrom (range (natGeneratingSequence _)) = m := by rw [natGeneratingSequence, range_enumerateCountable_of_mem _ empty_mem_countableGeneratingSet, generateFrom_countableGeneratingSet] lemma measurableSet_natGeneratingSequence [MeasurableSpace α] [CountablyGenerated α] (n : ℕ) : MeasurableSet (natGeneratingSequence α n) := measurableSet_countableGeneratingSet $ Set.enumerateCountable_mem _ empty_mem_countableGeneratingSet n
Mathlib/MeasureTheory/MeasurableSpace/CountablyGenerated.lean
96
101
theorem CountablyGenerated.comap [m : MeasurableSpace β] [h : CountablyGenerated β] (f : α → β) : @CountablyGenerated α (.comap f m) := by rcases h with ⟨⟨b, hbc, rfl⟩⟩
rcases h with ⟨⟨b, hbc, rfl⟩⟩ rw [comap_generateFrom] letI := generateFrom (preimage f '' b) exact ⟨_, hbc.image _, rfl⟩
true
import Mathlib.Algebra.Algebra.Operations import Mathlib.Algebra.Algebra.Subalgebra.Basic import Mathlib.Algebra.Ring.Subring.Pointwise import Mathlib.RingTheory.Adjoin.Basic #align_import algebra.algebra.subalgebra.pointwise from "leanprover-community/mathlib"@"b2c707cd190a58ea0565c86695a19e99ccecc215" namespace Subalgebra section Pointwise variable {R : Type*} {A : Type*} [CommSemiring R] [Semiring A] [Algebra R A]
Mathlib/Algebra/Algebra/Subalgebra/Pointwise.lean
27
32
theorem mul_toSubmodule_le (S T : Subalgebra R A) : (Subalgebra.toSubmodule S)* (Subalgebra.toSubmodule T) ≤ Subalgebra.toSubmodule (S ⊔ T) := by rw [Submodule.mul_le]
rw [Submodule.mul_le] intro y hy z hz show y * z ∈ S ⊔ T exact mul_mem (Algebra.mem_sup_left hy) (Algebra.mem_sup_right hz)
true
import Mathlib.MeasureTheory.Function.L1Space import Mathlib.MeasureTheory.Function.SimpleFuncDense #align_import measure_theory.function.simple_func_dense_lp from "leanprover-community/mathlib"@"5a2df4cd59cb31e97a516d4603a14bed5c2f9425" noncomputable section set_option linter.uppercaseLean3 false open Set Function Filter TopologicalSpace ENNReal EMetric Finset open scoped Classical Topology ENNReal MeasureTheory variable {α β ι E F 𝕜 : Type*} namespace MeasureTheory local infixr:25 " →ₛ " => SimpleFunc namespace SimpleFunc section Lp variable [MeasurableSpace β] [MeasurableSpace E] [NormedAddCommGroup E] [NormedAddCommGroup F] {q : ℝ} {p : ℝ≥0∞} theorem nnnorm_approxOn_le [OpensMeasurableSpace E] {f : β → E} (hf : Measurable f) {s : Set E} {y₀ : E} (h₀ : y₀ ∈ s) [SeparableSpace s] (x : β) (n : ℕ) : ‖approxOn f hf s y₀ h₀ n x - f x‖₊ ≤ ‖f x - y₀‖₊ := by have := edist_approxOn_le hf h₀ x n rw [edist_comm y₀] at this simp only [edist_nndist, nndist_eq_nnnorm] at this exact mod_cast this #align measure_theory.simple_func.nnnorm_approx_on_le MeasureTheory.SimpleFunc.nnnorm_approxOn_le theorem norm_approxOn_y₀_le [OpensMeasurableSpace E] {f : β → E} (hf : Measurable f) {s : Set E} {y₀ : E} (h₀ : y₀ ∈ s) [SeparableSpace s] (x : β) (n : ℕ) : ‖approxOn f hf s y₀ h₀ n x - y₀‖ ≤ ‖f x - y₀‖ + ‖f x - y₀‖ := by have := edist_approxOn_y0_le hf h₀ x n repeat rw [edist_comm y₀, edist_eq_coe_nnnorm_sub] at this exact mod_cast this #align measure_theory.simple_func.norm_approx_on_y₀_le MeasureTheory.SimpleFunc.norm_approxOn_y₀_le
Mathlib/MeasureTheory/Function/SimpleFuncDenseLp.lean
85
90
theorem norm_approxOn_zero_le [OpensMeasurableSpace E] {f : β → E} (hf : Measurable f) {s : Set E} (h₀ : (0 : E) ∈ s) [SeparableSpace s] (x : β) (n : ℕ) : ‖approxOn f hf s 0 h₀ n x‖ ≤ ‖f x‖ + ‖f x‖ := by have := edist_approxOn_y0_le hf h₀ x n
have := edist_approxOn_y0_le hf h₀ x n simp [edist_comm (0 : E), edist_eq_coe_nnnorm] at this exact mod_cast this
true
import Mathlib.Algebra.Group.Commute.Units import Mathlib.Algebra.Group.Int import Mathlib.Algebra.GroupWithZero.Semiconj import Mathlib.Data.Nat.GCD.Basic import Mathlib.Order.Bounds.Basic #align_import data.int.gcd from "leanprover-community/mathlib"@"47a1a73351de8dd6c8d3d32b569c8e434b03ca47" namespace Nat def xgcdAux : ℕ → ℤ → ℤ → ℕ → ℤ → ℤ → ℕ × ℤ × ℤ | 0, _, _, r', s', t' => (r', s', t') | succ k, s, t, r', s', t' => let q := r' / succ k xgcdAux (r' % succ k) (s' - q * s) (t' - q * t) (succ k) s t termination_by k => k decreasing_by exact mod_lt _ <| (succ_pos _).gt #align nat.xgcd_aux Nat.xgcdAux @[simp] theorem xgcd_zero_left {s t r' s' t'} : xgcdAux 0 s t r' s' t' = (r', s', t') := by simp [xgcdAux] #align nat.xgcd_zero_left Nat.xgcd_zero_left theorem xgcdAux_rec {r s t r' s' t'} (h : 0 < r) : xgcdAux r s t r' s' t' = xgcdAux (r' % r) (s' - r' / r * s) (t' - r' / r * t) r s t := by obtain ⟨r, rfl⟩ := Nat.exists_eq_succ_of_ne_zero h.ne' simp [xgcdAux] #align nat.xgcd_aux_rec Nat.xgcdAux_rec def xgcd (x y : ℕ) : ℤ × ℤ := (xgcdAux x 1 0 y 0 1).2 #align nat.xgcd Nat.xgcd def gcdA (x y : ℕ) : ℤ := (xgcd x y).1 #align nat.gcd_a Nat.gcdA def gcdB (x y : ℕ) : ℤ := (xgcd x y).2 #align nat.gcd_b Nat.gcdB @[simp] theorem gcdA_zero_left {s : ℕ} : gcdA 0 s = 0 := by unfold gcdA rw [xgcd, xgcd_zero_left] #align nat.gcd_a_zero_left Nat.gcdA_zero_left @[simp] theorem gcdB_zero_left {s : ℕ} : gcdB 0 s = 1 := by unfold gcdB rw [xgcd, xgcd_zero_left] #align nat.gcd_b_zero_left Nat.gcdB_zero_left @[simp] theorem gcdA_zero_right {s : ℕ} (h : s ≠ 0) : gcdA s 0 = 1 := by unfold gcdA xgcd obtain ⟨s, rfl⟩ := Nat.exists_eq_succ_of_ne_zero h rw [xgcdAux] simp #align nat.gcd_a_zero_right Nat.gcdA_zero_right @[simp]
Mathlib/Data/Int/GCD.lean
94
98
theorem gcdB_zero_right {s : ℕ} (h : s ≠ 0) : gcdB s 0 = 0 := by unfold gcdB xgcd
unfold gcdB xgcd obtain ⟨s, rfl⟩ := Nat.exists_eq_succ_of_ne_zero h rw [xgcdAux] simp
true
import Mathlib.Data.Bundle import Mathlib.Data.Set.Image import Mathlib.Topology.PartialHomeomorph import Mathlib.Topology.Order.Basic #align_import topology.fiber_bundle.trivialization from "leanprover-community/mathlib"@"e473c3198bb41f68560cab68a0529c854b618833" open TopologicalSpace Filter Set Bundle Function open scoped Topology Classical Bundle variable {ι : Type*} {B : Type*} {F : Type*} {E : B → Type*} variable (F) {Z : Type*} [TopologicalSpace B] [TopologicalSpace F] {proj : Z → B} structure Pretrivialization (proj : Z → B) extends PartialEquiv Z (B × F) where open_target : IsOpen target baseSet : Set B open_baseSet : IsOpen baseSet source_eq : source = proj ⁻¹' baseSet target_eq : target = baseSet ×ˢ univ proj_toFun : ∀ p ∈ source, (toFun p).1 = proj p #align pretrivialization Pretrivialization namespace Pretrivialization variable {F} variable (e : Pretrivialization F proj) {x : Z} @[coe] def toFun' : Z → (B × F) := e.toFun instance : CoeFun (Pretrivialization F proj) fun _ => Z → B × F := ⟨toFun'⟩ @[ext] lemma ext' (e e' : Pretrivialization F proj) (h₁ : e.toPartialEquiv = e'.toPartialEquiv) (h₂ : e.baseSet = e'.baseSet) : e = e' := by cases e; cases e'; congr #align pretrivialization.ext Pretrivialization.ext' -- Porting note (#11215): TODO: move `ext` here? lemma ext {e e' : Pretrivialization F proj} (h₁ : ∀ x, e x = e' x) (h₂ : ∀ x, e.toPartialEquiv.symm x = e'.toPartialEquiv.symm x) (h₃ : e.baseSet = e'.baseSet) : e = e' := by ext1 <;> [ext1; exact h₃] · apply h₁ · apply h₂ · rw [e.source_eq, e'.source_eq, h₃] lemma toPartialEquiv_injective [Nonempty F] : Injective (toPartialEquiv : Pretrivialization F proj → PartialEquiv Z (B × F)) := by refine fun e e' h ↦ ext' _ _ h ?_ simpa only [fst_image_prod, univ_nonempty, target_eq] using congr_arg (Prod.fst '' PartialEquiv.target ·) h @[simp, mfld_simps] theorem coe_coe : ⇑e.toPartialEquiv = e := rfl #align pretrivialization.coe_coe Pretrivialization.coe_coe @[simp, mfld_simps] theorem coe_fst (ex : x ∈ e.source) : (e x).1 = proj x := e.proj_toFun x ex #align pretrivialization.coe_fst Pretrivialization.coe_fst theorem mem_source : x ∈ e.source ↔ proj x ∈ e.baseSet := by rw [e.source_eq, mem_preimage] #align pretrivialization.mem_source Pretrivialization.mem_source theorem coe_fst' (ex : proj x ∈ e.baseSet) : (e x).1 = proj x := e.coe_fst (e.mem_source.2 ex) #align pretrivialization.coe_fst' Pretrivialization.coe_fst' protected theorem eqOn : EqOn (Prod.fst ∘ e) proj e.source := fun _ hx => e.coe_fst hx #align pretrivialization.eq_on Pretrivialization.eqOn theorem mk_proj_snd (ex : x ∈ e.source) : (proj x, (e x).2) = e x := Prod.ext (e.coe_fst ex).symm rfl #align pretrivialization.mk_proj_snd Pretrivialization.mk_proj_snd theorem mk_proj_snd' (ex : proj x ∈ e.baseSet) : (proj x, (e x).2) = e x := Prod.ext (e.coe_fst' ex).symm rfl #align pretrivialization.mk_proj_snd' Pretrivialization.mk_proj_snd' def setSymm : e.target → Z := e.target.restrict e.toPartialEquiv.symm #align pretrivialization.set_symm Pretrivialization.setSymm theorem mem_target {x : B × F} : x ∈ e.target ↔ x.1 ∈ e.baseSet := by rw [e.target_eq, prod_univ, mem_preimage] #align pretrivialization.mem_target Pretrivialization.mem_target
Mathlib/Topology/FiberBundle/Trivialization.lean
145
147
theorem proj_symm_apply {x : B × F} (hx : x ∈ e.target) : proj (e.toPartialEquiv.symm x) = x.1 := by have := (e.coe_fst (e.map_target hx)).symm
have := (e.coe_fst (e.map_target hx)).symm rwa [← e.coe_coe, e.right_inv hx] at this
true
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
Mathlib/MeasureTheory/Measure/MeasureSpace.lean
128
132
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, ←
rw [← measure_inter_add_diff (s ∪ t) ht, Set.union_inter_cancel_right, union_diff_right, ← measure_inter_add_diff s ht] ac_rfl
true
import Mathlib.Algebra.MvPolynomial.Rename #align_import data.mv_polynomial.comap from "leanprover-community/mathlib"@"aba31c938d3243cc671be7091b28a1e0814647ee" namespace MvPolynomial variable {σ : Type*} {τ : Type*} {υ : Type*} {R : Type*} [CommSemiring R] noncomputable def comap (f : MvPolynomial σ R →ₐ[R] MvPolynomial τ R) : (τ → R) → σ → R := fun x i => aeval x (f (X i)) #align mv_polynomial.comap MvPolynomial.comap @[simp] theorem comap_apply (f : MvPolynomial σ R →ₐ[R] MvPolynomial τ R) (x : τ → R) (i : σ) : comap f x i = aeval x (f (X i)) := rfl #align mv_polynomial.comap_apply MvPolynomial.comap_apply @[simp] theorem comap_id_apply (x : σ → R) : comap (AlgHom.id R (MvPolynomial σ R)) x = x := by funext i simp only [comap, AlgHom.id_apply, id, aeval_X] #align mv_polynomial.comap_id_apply MvPolynomial.comap_id_apply variable (σ R) theorem comap_id : comap (AlgHom.id R (MvPolynomial σ R)) = id := by funext x exact comap_id_apply x #align mv_polynomial.comap_id MvPolynomial.comap_id variable {σ R}
Mathlib/Algebra/MvPolynomial/Comap.lean
62
74
theorem comap_comp_apply (f : MvPolynomial σ R →ₐ[R] MvPolynomial τ R) (g : MvPolynomial τ R →ₐ[R] MvPolynomial υ R) (x : υ → R) : comap (g.comp f) x = comap f (comap g x) := by funext i
funext i trans aeval x (aeval (fun i => g (X i)) (f (X i))) · apply eval₂Hom_congr rfl rfl rw [AlgHom.comp_apply] suffices g = aeval fun i => g (X i) by rw [← this] exact aeval_unique g · simp only [comap, aeval_eq_eval₂Hom, map_eval₂Hom, AlgHom.comp_apply] refine eval₂Hom_congr ?_ rfl rfl ext r apply aeval_C
true
import Mathlib.Order.Filter.Basic import Mathlib.Order.Filter.CountableInter import Mathlib.SetTheory.Cardinal.Ordinal import Mathlib.SetTheory.Cardinal.Cofinality open Set Filter Cardinal universe u variable {ι : Type u} {α β : Type u} {c : Cardinal.{u}} class CardinalInterFilter (l : Filter α) (c : Cardinal.{u}) : Prop where cardinal_sInter_mem : ∀ S : Set (Set α), (#S < c) → (∀ s ∈ S, s ∈ l) → ⋂₀ S ∈ l variable {l : Filter α} theorem cardinal_sInter_mem {S : Set (Set α)} [CardinalInterFilter l c] (hSc : #S < c) : ⋂₀ S ∈ l ↔ ∀ s ∈ S, s ∈ l := ⟨fun hS _s hs => mem_of_superset hS (sInter_subset_of_mem hs), CardinalInterFilter.cardinal_sInter_mem _ hSc⟩ theorem _root_.Filter.cardinalInterFilter_aleph0 (l : Filter α) : CardinalInterFilter l aleph0 where cardinal_sInter_mem := by simp_all only [aleph_zero, lt_aleph0_iff_subtype_finite, setOf_mem_eq, sInter_mem, implies_true, forall_const] theorem CardinalInterFilter.toCountableInterFilter (l : Filter α) [CardinalInterFilter l c] (hc : aleph0 < c) : CountableInterFilter l where countable_sInter_mem S hS a := CardinalInterFilter.cardinal_sInter_mem S (lt_of_le_of_lt (Set.Countable.le_aleph0 hS) hc) a instance CountableInterFilter.toCardinalInterFilter (l : Filter α) [CountableInterFilter l] : CardinalInterFilter l (aleph 1) where cardinal_sInter_mem S hS a := CountableInterFilter.countable_sInter_mem S ((countable_iff_lt_aleph_one S).mpr hS) a theorem cardinalInterFilter_aleph_one_iff : CardinalInterFilter l (aleph 1) ↔ CountableInterFilter l := ⟨fun _ ↦ ⟨fun S h a ↦ CardinalInterFilter.cardinal_sInter_mem S ((countable_iff_lt_aleph_one S).1 h) a⟩, fun _ ↦ CountableInterFilter.toCardinalInterFilter l⟩ theorem CardinalInterFilter.of_cardinalInterFilter_of_le (l : Filter α) [CardinalInterFilter l c] {a : Cardinal.{u}} (hac : a ≤ c) : CardinalInterFilter l a where cardinal_sInter_mem S hS a := CardinalInterFilter.cardinal_sInter_mem S (lt_of_lt_of_le hS hac) a theorem CardinalInterFilter.of_cardinalInterFilter_of_lt (l : Filter α) [CardinalInterFilter l c] {a : Cardinal.{u}} (hac : a < c) : CardinalInterFilter l a := CardinalInterFilter.of_cardinalInterFilter_of_le l (hac.le) namespace Filter variable [CardinalInterFilter l c] theorem cardinal_iInter_mem {s : ι → Set α} (hic : #ι < c) : (⋂ i, s i) ∈ l ↔ ∀ i, s i ∈ l := by rw [← sInter_range _] apply (cardinal_sInter_mem (lt_of_le_of_lt Cardinal.mk_range_le hic)).trans exact forall_mem_range theorem cardinal_bInter_mem {S : Set ι} (hS : #S < c) {s : ∀ i ∈ S, Set α} : (⋂ i, ⋂ hi : i ∈ S, s i ‹_›) ∈ l ↔ ∀ i, ∀ hi : i ∈ S, s i ‹_› ∈ l := by rw [biInter_eq_iInter] exact (cardinal_iInter_mem hS).trans Subtype.forall theorem eventually_cardinal_forall {p : α → ι → Prop} (hic : #ι < c) : (∀ᶠ x in l, ∀ i, p x i) ↔ ∀ i, ∀ᶠ x in l, p x i := by simp only [Filter.Eventually, setOf_forall] exact cardinal_iInter_mem hic theorem eventually_cardinal_ball {S : Set ι} (hS : #S < c) {p : α → ∀ i ∈ S, Prop} : (∀ᶠ x in l, ∀ i hi, p x i hi) ↔ ∀ i hi, ∀ᶠ x in l, p x i hi := by simp only [Filter.Eventually, setOf_forall] exact cardinal_bInter_mem hS theorem EventuallyLE.cardinal_iUnion {s t : ι → Set α} (hic : #ι < c) (h : ∀ i, s i ≤ᶠ[l] t i) : ⋃ i, s i ≤ᶠ[l] ⋃ i, t i := ((eventually_cardinal_forall hic).2 h).mono fun _ hst hs => mem_iUnion.2 <| (mem_iUnion.1 hs).imp hst theorem EventuallyEq.cardinal_iUnion {s t : ι → Set α} (hic : #ι < c) (h : ∀ i, s i =ᶠ[l] t i) : ⋃ i, s i =ᶠ[l] ⋃ i, t i := (EventuallyLE.cardinal_iUnion hic fun i => (h i).le).antisymm (EventuallyLE.cardinal_iUnion hic fun i => (h i).symm.le)
Mathlib/Order/Filter/CardinalInter.lean
123
127
theorem EventuallyLE.cardinal_bUnion {S : Set ι} (hS : #S < c) {s t : ∀ i ∈ S, Set α} (h : ∀ i hi, s i hi ≤ᶠ[l] t i hi) : ⋃ i ∈ S, s i ‹_› ≤ᶠ[l] ⋃ i ∈ S, t i ‹_› := by simp only [biUnion_eq_iUnion]
simp only [biUnion_eq_iUnion] exact EventuallyLE.cardinal_iUnion hS fun i => h i i.2
true
import Mathlib.GroupTheory.QuotientGroup import Mathlib.RingTheory.DedekindDomain.Ideal #align_import ring_theory.class_group from "leanprover-community/mathlib"@"565eb991e264d0db702722b4bde52ee5173c9950" variable {R K L : Type*} [CommRing R] variable [Field K] [Field L] [DecidableEq L] variable [Algebra R K] [IsFractionRing R K] variable [Algebra K L] [FiniteDimensional K L] variable [Algebra R L] [IsScalarTower R K L] open scoped nonZeroDivisors open IsLocalization IsFractionRing FractionalIdeal Units section variable (R K) irreducible_def toPrincipalIdeal : Kˣ →* (FractionalIdeal R⁰ K)ˣ := { toFun := fun x => ⟨spanSingleton _ x, spanSingleton _ x⁻¹, by simp only [spanSingleton_one, Units.mul_inv', spanSingleton_mul_spanSingleton], by simp only [spanSingleton_one, Units.inv_mul', spanSingleton_mul_spanSingleton]⟩ map_mul' := fun x y => ext (by simp only [Units.val_mk, Units.val_mul, spanSingleton_mul_spanSingleton]) map_one' := ext (by simp only [spanSingleton_one, Units.val_mk, Units.val_one]) } #align to_principal_ideal toPrincipalIdeal variable {R K} @[simp] theorem coe_toPrincipalIdeal (x : Kˣ) : (toPrincipalIdeal R K x : FractionalIdeal R⁰ K) = spanSingleton _ (x : K) := by simp only [toPrincipalIdeal]; rfl #align coe_to_principal_ideal coe_toPrincipalIdeal @[simp] theorem toPrincipalIdeal_eq_iff {I : (FractionalIdeal R⁰ K)ˣ} {x : Kˣ} : toPrincipalIdeal R K x = I ↔ spanSingleton R⁰ (x : K) = I := by simp only [toPrincipalIdeal]; exact Units.ext_iff #align to_principal_ideal_eq_iff toPrincipalIdeal_eq_iff theorem mem_principal_ideals_iff {I : (FractionalIdeal R⁰ K)ˣ} : I ∈ (toPrincipalIdeal R K).range ↔ ∃ x : K, spanSingleton R⁰ x = I := by simp only [MonoidHom.mem_range, toPrincipalIdeal_eq_iff] constructor <;> rintro ⟨x, hx⟩ · exact ⟨x, hx⟩ · refine ⟨Units.mk0 x ?_, hx⟩ rintro rfl simp [I.ne_zero.symm] at hx #align mem_principal_ideals_iff mem_principal_ideals_iff instance PrincipalIdeals.normal : (toPrincipalIdeal R K).range.Normal := Subgroup.normal_of_comm _ #align principal_ideals.normal PrincipalIdeals.normal end variable (R) variable [IsDomain R] def ClassGroup := (FractionalIdeal R⁰ (FractionRing R))ˣ ⧸ (toPrincipalIdeal R (FractionRing R)).range #align class_group ClassGroup noncomputable instance : CommGroup (ClassGroup R) := QuotientGroup.Quotient.commGroup (toPrincipalIdeal R (FractionRing R)).range noncomputable instance : Inhabited (ClassGroup R) := ⟨1⟩ variable {R} noncomputable def ClassGroup.mk : (FractionalIdeal R⁰ K)ˣ →* ClassGroup R := (QuotientGroup.mk' (toPrincipalIdeal R (FractionRing R)).range).comp (Units.map (FractionalIdeal.canonicalEquiv R⁰ K (FractionRing R))) #align class_group.mk ClassGroup.mk -- Can't be `@[simp]` because it can't figure out the quotient relation.
Mathlib/RingTheory/ClassGroup.lean
111
117
theorem ClassGroup.Quot_mk_eq_mk (I : (FractionalIdeal R⁰ (FractionRing R))ˣ) : Quot.mk _ I = ClassGroup.mk I := by rw [ClassGroup.mk, canonicalEquiv_self, RingEquiv.coe_monoidHom_refl, Units.map_id]
rw [ClassGroup.mk, canonicalEquiv_self, RingEquiv.coe_monoidHom_refl, Units.map_id] -- This used to be `rw`, but we need `erw` after leanprover/lean4#2644 erw [MonoidHom.comp_apply] rw [MonoidHom.id_apply, QuotientGroup.mk'_apply] rfl
true
import Mathlib.LinearAlgebra.Matrix.BilinearForm import Mathlib.LinearAlgebra.Matrix.Charpoly.Minpoly import Mathlib.LinearAlgebra.Determinant import Mathlib.LinearAlgebra.FiniteDimensional import Mathlib.LinearAlgebra.Vandermonde import Mathlib.LinearAlgebra.Trace import Mathlib.FieldTheory.IsAlgClosed.AlgebraicClosure import Mathlib.FieldTheory.PrimitiveElement import Mathlib.FieldTheory.Galois import Mathlib.RingTheory.PowerBasis import Mathlib.FieldTheory.Minpoly.MinpolyDiv #align_import ring_theory.trace from "leanprover-community/mathlib"@"3e068ece210655b7b9a9477c3aff38a492400aa1" universe u v w z variable {R S T : Type*} [CommRing R] [CommRing S] [CommRing T] variable [Algebra R S] [Algebra R T] variable {K L : Type*} [Field K] [Field L] [Algebra K L] variable {ι κ : Type w} [Fintype ι] open FiniteDimensional open LinearMap (BilinForm) open LinearMap open Matrix open scoped Matrix namespace Algebra variable (b : Basis ι R S) variable (R S) noncomputable def trace : S →ₗ[R] R := (LinearMap.trace R S).comp (lmul R S).toLinearMap #align algebra.trace Algebra.trace variable {S} -- Not a `simp` lemma since there are more interesting ways to rewrite `trace R S x`, -- for example `trace_trace` theorem trace_apply (x) : trace R S x = LinearMap.trace R S (lmul R S x) := rfl #align algebra.trace_apply Algebra.trace_apply theorem trace_eq_zero_of_not_exists_basis (h : ¬∃ s : Finset S, Nonempty (Basis s R S)) : trace R S = 0 := by ext s; simp [trace_apply, LinearMap.trace, h] #align algebra.trace_eq_zero_of_not_exists_basis Algebra.trace_eq_zero_of_not_exists_basis variable {R} -- Can't be a `simp` lemma because it depends on a choice of basis theorem trace_eq_matrix_trace [DecidableEq ι] (b : Basis ι R S) (s : S) : trace R S s = Matrix.trace (Algebra.leftMulMatrix b s) := by rw [trace_apply, LinearMap.trace_eq_matrix_trace _ b, ← toMatrix_lmul_eq]; rfl #align algebra.trace_eq_matrix_trace Algebra.trace_eq_matrix_trace theorem trace_algebraMap_of_basis (x : R) : trace R S (algebraMap R S x) = Fintype.card ι • x := by haveI := Classical.decEq ι rw [trace_apply, LinearMap.trace_eq_matrix_trace R b, Matrix.trace] convert Finset.sum_const x simp [-coe_lmul_eq_mul] #align algebra.trace_algebra_map_of_basis Algebra.trace_algebraMap_of_basis @[simp] theorem trace_algebraMap (x : K) : trace K L (algebraMap K L x) = finrank K L • x := by by_cases H : ∃ s : Finset L, Nonempty (Basis s K L) · rw [trace_algebraMap_of_basis H.choose_spec.some, finrank_eq_card_basis H.choose_spec.some] · simp [trace_eq_zero_of_not_exists_basis K H, finrank_eq_zero_of_not_exists_basis_finset H] #align algebra.trace_algebra_map Algebra.trace_algebraMap theorem trace_trace_of_basis [Algebra S T] [IsScalarTower R S T] {ι κ : Type*} [Finite ι] [Finite κ] (b : Basis ι R S) (c : Basis κ S T) (x : T) : trace R S (trace S T x) = trace R T x := by haveI := Classical.decEq ι haveI := Classical.decEq κ cases nonempty_fintype ι cases nonempty_fintype κ rw [trace_eq_matrix_trace (b.smul c), trace_eq_matrix_trace b, trace_eq_matrix_trace c, Matrix.trace, Matrix.trace, Matrix.trace, ← Finset.univ_product_univ, Finset.sum_product] refine Finset.sum_congr rfl fun i _ ↦ ?_ simp only [AlgHom.map_sum, smul_leftMulMatrix, Finset.sum_apply, Matrix.diag, Finset.sum_apply i (Finset.univ : Finset κ) fun y => leftMulMatrix b (leftMulMatrix c x y y)] #align algebra.trace_trace_of_basis Algebra.trace_trace_of_basis
Mathlib/RingTheory/Trace.lean
149
153
theorem trace_comp_trace_of_basis [Algebra S T] [IsScalarTower R S T] {ι κ : Type*} [Finite ι] [Finite κ] (b : Basis ι R S) (c : Basis κ S T) : (trace R S).comp ((trace S T).restrictScalars R) = trace R T := by ext
ext rw [LinearMap.comp_apply, LinearMap.restrictScalars_apply, trace_trace_of_basis b c]
true
import Mathlib.Algebra.CharP.Defs import Mathlib.Algebra.MvPolynomial.Degrees import Mathlib.Algebra.Polynomial.AlgebraMap import Mathlib.LinearAlgebra.FinsuppVectorSpace import Mathlib.LinearAlgebra.FreeModule.Finite.Basic #align_import ring_theory.mv_polynomial.basic from "leanprover-community/mathlib"@"2f5b500a507264de86d666a5f87ddb976e2d8de4" noncomputable section open Set LinearMap Submodule open Polynomial universe u v variable (σ : Type u) (R : Type v) [CommSemiring R] (p m : ℕ) namespace MvPolynomial section Homomorphism
Mathlib/RingTheory/MvPolynomial/Basic.lean
68
72
theorem mapRange_eq_map {R S : Type*} [CommSemiring R] [CommSemiring S] (p : MvPolynomial σ R) (f : R →+* S) : Finsupp.mapRange f f.map_zero p = map f p := by rw [p.as_sum, Finsupp.mapRange_finset_sum, map_sum (map f)]
rw [p.as_sum, Finsupp.mapRange_finset_sum, map_sum (map f)] refine Finset.sum_congr rfl fun n _ => ?_ rw [map_monomial, ← single_eq_monomial, Finsupp.mapRange_single, single_eq_monomial]
true
import Mathlib.RingTheory.PrincipalIdealDomain import Mathlib.RingTheory.Ideal.LocalRing import Mathlib.RingTheory.Valuation.PrimeMultiplicity import Mathlib.RingTheory.AdicCompletion.Basic #align_import ring_theory.discrete_valuation_ring.basic from "leanprover-community/mathlib"@"c163ec99dfc664628ca15d215fce0a5b9c265b68" open scoped Classical universe u open Ideal LocalRing class DiscreteValuationRing (R : Type u) [CommRing R] [IsDomain R] extends IsPrincipalIdealRing R, LocalRing R : Prop where not_a_field' : maximalIdeal R ≠ ⊥ #align discrete_valuation_ring DiscreteValuationRing namespace DiscreteValuationRing variable (R : Type u) [CommRing R] [IsDomain R] [DiscreteValuationRing R] theorem not_a_field : maximalIdeal R ≠ ⊥ := not_a_field' #align discrete_valuation_ring.not_a_field DiscreteValuationRing.not_a_field theorem not_isField : ¬IsField R := LocalRing.isField_iff_maximalIdeal_eq.not.mpr (not_a_field R) #align discrete_valuation_ring.not_is_field DiscreteValuationRing.not_isField variable {R} open PrincipalIdealRing
Mathlib/RingTheory/DiscreteValuationRing/Basic.lean
75
88
theorem irreducible_of_span_eq_maximalIdeal {R : Type*} [CommRing R] [LocalRing R] [IsDomain R] (ϖ : R) (hϖ : ϖ ≠ 0) (h : maximalIdeal R = Ideal.span {ϖ}) : Irreducible ϖ := by have h2 : ¬IsUnit ϖ := show ϖ ∈ maximalIdeal R from h.symm ▸ Submodule.mem_span_singleton_self ϖ
have h2 : ¬IsUnit ϖ := show ϖ ∈ maximalIdeal R from h.symm ▸ Submodule.mem_span_singleton_self ϖ refine ⟨h2, ?_⟩ intro a b hab by_contra! h obtain ⟨ha : a ∈ maximalIdeal R, hb : b ∈ maximalIdeal R⟩ := h rw [h, mem_span_singleton'] at ha hb rcases ha with ⟨a, rfl⟩ rcases hb with ⟨b, rfl⟩ rw [show a * ϖ * (b * ϖ) = ϖ * (ϖ * (a * b)) by ring] at hab apply hϖ apply eq_zero_of_mul_eq_self_right _ hab.symm exact fun hh => h2 (isUnit_of_dvd_one ⟨_, hh.symm⟩)
true
import Mathlib.RingTheory.WittVector.Frobenius import Mathlib.RingTheory.WittVector.Verschiebung import Mathlib.RingTheory.WittVector.MulP #align_import ring_theory.witt_vector.identities from "leanprover-community/mathlib"@"0798037604b2d91748f9b43925fb7570a5f3256c" namespace WittVector variable {p : ℕ} {R : Type*} [hp : Fact p.Prime] [CommRing R] -- type as `\bbW` local notation "𝕎" => WittVector p noncomputable section -- Porting note: `ghost_calc` failure: `simp only []` and the manual instances had to be added. theorem frobenius_verschiebung (x : 𝕎 R) : frobenius (verschiebung x) = x * p := by have : IsPoly p fun {R} [CommRing R] x ↦ frobenius (verschiebung x) := IsPoly.comp (hg := frobenius_isPoly p) (hf := verschiebung_isPoly) have : IsPoly p fun {R} [CommRing R] x ↦ x * p := mulN_isPoly p p ghost_calc x ghost_simp [mul_comm] #align witt_vector.frobenius_verschiebung WittVector.frobenius_verschiebung theorem verschiebung_zmod (x : 𝕎 (ZMod p)) : verschiebung x = x * p := by rw [← frobenius_verschiebung, frobenius_zmodp] #align witt_vector.verschiebung_zmod WittVector.verschiebung_zmod variable (p R) theorem coeff_p_pow [CharP R p] (i : ℕ) : ((p : 𝕎 R) ^ i).coeff i = 1 := by induction' i with i h · simp only [Nat.zero_eq, one_coeff_zero, Ne, pow_zero] · rw [pow_succ, ← frobenius_verschiebung, coeff_frobenius_charP, verschiebung_coeff_succ, h, one_pow] #align witt_vector.coeff_p_pow WittVector.coeff_p_pow theorem coeff_p_pow_eq_zero [CharP R p] {i j : ℕ} (hj : j ≠ i) : ((p : 𝕎 R) ^ i).coeff j = 0 := by induction' i with i hi generalizing j · rw [pow_zero, one_coeff_eq_of_pos] exact Nat.pos_of_ne_zero hj · rw [pow_succ, ← frobenius_verschiebung, coeff_frobenius_charP] cases j · rw [verschiebung_coeff_zero, zero_pow hp.out.ne_zero] · rw [verschiebung_coeff_succ, hi (ne_of_apply_ne _ hj), zero_pow hp.out.ne_zero] #align witt_vector.coeff_p_pow_eq_zero WittVector.coeff_p_pow_eq_zero theorem coeff_p [CharP R p] (i : ℕ) : (p : 𝕎 R).coeff i = if i = 1 then 1 else 0 := by split_ifs with hi · simpa only [hi, pow_one] using coeff_p_pow p R 1 · simpa only [pow_one] using coeff_p_pow_eq_zero p R hi #align witt_vector.coeff_p WittVector.coeff_p @[simp] theorem coeff_p_zero [CharP R p] : (p : 𝕎 R).coeff 0 = 0 := by rw [coeff_p, if_neg] exact zero_ne_one #align witt_vector.coeff_p_zero WittVector.coeff_p_zero @[simp] theorem coeff_p_one [CharP R p] : (p : 𝕎 R).coeff 1 = 1 := by rw [coeff_p, if_pos rfl] #align witt_vector.coeff_p_one WittVector.coeff_p_one theorem p_nonzero [Nontrivial R] [CharP R p] : (p : 𝕎 R) ≠ 0 := by intro h simpa only [h, zero_coeff, zero_ne_one] using coeff_p_one p R #align witt_vector.p_nonzero WittVector.p_nonzero theorem FractionRing.p_nonzero [Nontrivial R] [CharP R p] : (p : FractionRing (𝕎 R)) ≠ 0 := by simpa using (IsFractionRing.injective (𝕎 R) (FractionRing (𝕎 R))).ne (WittVector.p_nonzero _ _) #align witt_vector.fraction_ring.p_nonzero WittVector.FractionRing.p_nonzero variable {p R} -- Porting note: `ghost_calc` failure: `simp only []` and the manual instances had to be added. theorem verschiebung_mul_frobenius (x y : 𝕎 R) : verschiebung (x * frobenius y) = verschiebung x * y := by have : IsPoly₂ p fun {R} [Rcr : CommRing R] x y ↦ verschiebung (x * frobenius y) := IsPoly.comp₂ (hg := verschiebung_isPoly) (hf := IsPoly₂.comp (hh := mulIsPoly₂) (hf := idIsPolyI' p) (hg := frobenius_isPoly p)) have : IsPoly₂ p fun {R} [CommRing R] x y ↦ verschiebung x * y := IsPoly₂.comp (hh := mulIsPoly₂) (hf := verschiebung_isPoly) (hg := idIsPolyI' p) ghost_calc x y rintro ⟨⟩ <;> ghost_simp [mul_assoc] #align witt_vector.verschiebung_mul_frobenius WittVector.verschiebung_mul_frobenius
Mathlib/RingTheory/WittVector/Identities.lean
114
116
theorem mul_charP_coeff_zero [CharP R p] (x : 𝕎 R) : (x * p).coeff 0 = 0 := by rw [← frobenius_verschiebung, coeff_frobenius_charP, verschiebung_coeff_zero,
rw [← frobenius_verschiebung, coeff_frobenius_charP, verschiebung_coeff_zero, zero_pow hp.out.ne_zero]
true
import Mathlib.Algebra.Polynomial.Degree.Definitions import Mathlib.Algebra.Polynomial.Induction #align_import data.polynomial.eval from "leanprover-community/mathlib"@"728baa2f54e6062c5879a3e397ac6bac323e506f" set_option linter.uppercaseLean3 false noncomputable section open Finset AddMonoidAlgebra open Polynomial namespace Polynomial universe u v w y variable {R : Type u} {S : Type v} {T : Type w} {ι : Type y} {a b : R} {m n : ℕ} section Semiring variable [Semiring R] {p q r : R[X]} section variable [Semiring S] variable (f : R →+* S) (x : S) irreducible_def eval₂ (p : R[X]) : S := p.sum fun e a => f a * x ^ e #align polynomial.eval₂ Polynomial.eval₂ theorem eval₂_eq_sum {f : R →+* S} {x : S} : p.eval₂ f x = p.sum fun e a => f a * x ^ e := by rw [eval₂_def] #align polynomial.eval₂_eq_sum Polynomial.eval₂_eq_sum theorem eval₂_congr {R S : Type*} [Semiring R] [Semiring S] {f g : R →+* S} {s t : S} {φ ψ : R[X]} : f = g → s = t → φ = ψ → eval₂ f s φ = eval₂ g t ψ := by rintro rfl rfl rfl; rfl #align polynomial.eval₂_congr Polynomial.eval₂_congr @[simp] theorem eval₂_at_zero : p.eval₂ f 0 = f (coeff p 0) := by simp (config := { contextual := true }) only [eval₂_eq_sum, zero_pow_eq, mul_ite, mul_zero, mul_one, sum, Classical.not_not, mem_support_iff, sum_ite_eq', ite_eq_left_iff, RingHom.map_zero, imp_true_iff, eq_self_iff_true] #align polynomial.eval₂_at_zero Polynomial.eval₂_at_zero @[simp] theorem eval₂_zero : (0 : R[X]).eval₂ f x = 0 := by simp [eval₂_eq_sum] #align polynomial.eval₂_zero Polynomial.eval₂_zero @[simp] theorem eval₂_C : (C a).eval₂ f x = f a := by simp [eval₂_eq_sum] #align polynomial.eval₂_C Polynomial.eval₂_C @[simp] theorem eval₂_X : X.eval₂ f x = x := by simp [eval₂_eq_sum] #align polynomial.eval₂_X Polynomial.eval₂_X @[simp] theorem eval₂_monomial {n : ℕ} {r : R} : (monomial n r).eval₂ f x = f r * x ^ n := by simp [eval₂_eq_sum] #align polynomial.eval₂_monomial Polynomial.eval₂_monomial @[simp] theorem eval₂_X_pow {n : ℕ} : (X ^ n).eval₂ f x = x ^ n := by rw [X_pow_eq_monomial] convert eval₂_monomial f x (n := n) (r := 1) simp #align polynomial.eval₂_X_pow Polynomial.eval₂_X_pow @[simp] theorem eval₂_add : (p + q).eval₂ f x = p.eval₂ f x + q.eval₂ f x := by simp only [eval₂_eq_sum] apply sum_add_index <;> simp [add_mul] #align polynomial.eval₂_add Polynomial.eval₂_add @[simp]
Mathlib/Algebra/Polynomial/Eval.lean
95
95
theorem eval₂_one : (1 : R[X]).eval₂ f x = 1 := by
rw [← C_1, eval₂_C, f.map_one]
true
import Mathlib.Analysis.Calculus.Deriv.Inv import Mathlib.Analysis.Calculus.Deriv.Polynomial import Mathlib.Analysis.SpecialFunctions.ExpDeriv import Mathlib.Analysis.SpecialFunctions.PolynomialExp #align_import analysis.calculus.bump_function_inner from "leanprover-community/mathlib"@"3bce8d800a6f2b8f63fe1e588fd76a9ff4adcebe" noncomputable section open scoped Classical Topology open Polynomial Real Filter Set Function open scoped Polynomial def expNegInvGlue (x : ℝ) : ℝ := if x ≤ 0 then 0 else exp (-x⁻¹) #align exp_neg_inv_glue expNegInvGlue namespace expNegInvGlue theorem zero_of_nonpos {x : ℝ} (hx : x ≤ 0) : expNegInvGlue x = 0 := by simp [expNegInvGlue, hx] #align exp_neg_inv_glue.zero_of_nonpos expNegInvGlue.zero_of_nonpos @[simp] -- Porting note (#10756): new lemma protected theorem zero : expNegInvGlue 0 = 0 := zero_of_nonpos le_rfl theorem pos_of_pos {x : ℝ} (hx : 0 < x) : 0 < expNegInvGlue x := by simp [expNegInvGlue, not_le.2 hx, exp_pos] #align exp_neg_inv_glue.pos_of_pos expNegInvGlue.pos_of_pos theorem nonneg (x : ℝ) : 0 ≤ expNegInvGlue x := by cases le_or_gt x 0 with | inl h => exact ge_of_eq (zero_of_nonpos h) | inr h => exact le_of_lt (pos_of_pos h) #align exp_neg_inv_glue.nonneg expNegInvGlue.nonneg -- Porting note (#10756): new lemma @[simp] theorem zero_iff_nonpos {x : ℝ} : expNegInvGlue x = 0 ↔ x ≤ 0 := ⟨fun h ↦ not_lt.mp fun h' ↦ (pos_of_pos h').ne' h, zero_of_nonpos⟩ #noalign exp_neg_inv_glue.P_aux #noalign exp_neg_inv_glue.f_aux #noalign exp_neg_inv_glue.f_aux_zero_eq #noalign exp_neg_inv_glue.f_aux_deriv #noalign exp_neg_inv_glue.f_aux_deriv_pos #noalign exp_neg_inv_glue.f_aux_limit #noalign exp_neg_inv_glue.f_aux_deriv_zero #noalign exp_neg_inv_glue.f_aux_has_deriv_at theorem tendsto_polynomial_inv_mul_zero (p : ℝ[X]) : Tendsto (fun x ↦ p.eval x⁻¹ * expNegInvGlue x) (𝓝 0) (𝓝 0) := by simp only [expNegInvGlue, mul_ite, mul_zero] refine tendsto_const_nhds.if ?_ simp only [not_le] have : Tendsto (fun x ↦ p.eval x⁻¹ / exp x⁻¹) (𝓝[>] 0) (𝓝 0) := p.tendsto_div_exp_atTop.comp tendsto_inv_zero_atTop refine this.congr' <| mem_of_superset self_mem_nhdsWithin fun x hx ↦ ?_ simp [expNegInvGlue, hx.out.not_le, exp_neg, div_eq_mul_inv]
Mathlib/Analysis/SpecialFunctions/SmoothTransition.lean
101
117
theorem hasDerivAt_polynomial_eval_inv_mul (p : ℝ[X]) (x : ℝ) : HasDerivAt (fun x ↦ p.eval x⁻¹ * expNegInvGlue x) ((X ^ 2 * (p - derivative (R := ℝ) p)).eval x⁻¹ * expNegInvGlue x) x := by rcases lt_trichotomy x 0 with hx | rfl | hx
rcases lt_trichotomy x 0 with hx | rfl | hx · rw [zero_of_nonpos hx.le, mul_zero] refine (hasDerivAt_const _ 0).congr_of_eventuallyEq ?_ filter_upwards [gt_mem_nhds hx] with y hy rw [zero_of_nonpos hy.le, mul_zero] · rw [expNegInvGlue.zero, mul_zero, hasDerivAt_iff_tendsto_slope] refine ((tendsto_polynomial_inv_mul_zero (p * X)).mono_left inf_le_left).congr fun x ↦ ?_ simp [slope_def_field, div_eq_mul_inv, mul_right_comm] · have := ((p.hasDerivAt x⁻¹).mul (hasDerivAt_neg _).exp).comp x (hasDerivAt_inv hx.ne') convert this.congr_of_eventuallyEq _ using 1 · simp [expNegInvGlue, hx.not_le] ring · filter_upwards [lt_mem_nhds hx] with y hy simp [expNegInvGlue, hy.not_le]
true
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 Submatrix @[simp] theorem submatrix_empty (A : Matrix m' n' α) (row : Fin 0 → m') (col : o' → n') : submatrix A row col = ![] := empty_eq _ #align matrix.submatrix_empty Matrix.submatrix_empty @[simp]
Mathlib/Data/Matrix/Notation.lean
393
396
theorem submatrix_cons_row (A : Matrix m' n' α) (i : m') (row : Fin m → m') (col : o' → n') : submatrix A (vecCons i row) col = vecCons (fun j => A i (col j)) (submatrix A row col) := by ext i j
ext i j refine Fin.cases ?_ ?_ i <;> simp [submatrix]
true
import Mathlib.Analysis.SpecialFunctions.Pow.Continuity import Mathlib.Analysis.SpecialFunctions.Complex.LogDeriv import Mathlib.Analysis.Calculus.FDeriv.Extend import Mathlib.Analysis.Calculus.Deriv.Prod import Mathlib.Analysis.SpecialFunctions.Log.Deriv import Mathlib.Analysis.SpecialFunctions.Trigonometric.Deriv #align_import analysis.special_functions.pow.deriv from "leanprover-community/mathlib"@"3bce8d800a6f2b8f63fe1e588fd76a9ff4adcebe" noncomputable section open scoped Classical Real Topology NNReal ENNReal Filter open Filter namespace Complex theorem hasStrictFDerivAt_cpow {p : ℂ × ℂ} (hp : p.1 ∈ slitPlane) : HasStrictFDerivAt (fun x : ℂ × ℂ => x.1 ^ x.2) ((p.2 * p.1 ^ (p.2 - 1)) • ContinuousLinearMap.fst ℂ ℂ ℂ + (p.1 ^ p.2 * log p.1) • ContinuousLinearMap.snd ℂ ℂ ℂ) p := by have A : p.1 ≠ 0 := slitPlane_ne_zero hp have : (fun x : ℂ × ℂ => x.1 ^ x.2) =ᶠ[𝓝 p] fun x => exp (log x.1 * x.2) := ((isOpen_ne.preimage continuous_fst).eventually_mem A).mono fun p hp => cpow_def_of_ne_zero hp _ rw [cpow_sub _ _ A, cpow_one, mul_div_left_comm, mul_smul, mul_smul] refine HasStrictFDerivAt.congr_of_eventuallyEq ?_ this.symm simpa only [cpow_def_of_ne_zero A, div_eq_mul_inv, mul_smul, add_comm, smul_add] using ((hasStrictFDerivAt_fst.clog hp).mul hasStrictFDerivAt_snd).cexp #align complex.has_strict_fderiv_at_cpow Complex.hasStrictFDerivAt_cpow theorem hasStrictFDerivAt_cpow' {x y : ℂ} (hp : x ∈ slitPlane) : HasStrictFDerivAt (fun x : ℂ × ℂ => x.1 ^ x.2) ((y * x ^ (y - 1)) • ContinuousLinearMap.fst ℂ ℂ ℂ + (x ^ y * log x) • ContinuousLinearMap.snd ℂ ℂ ℂ) (x, y) := @hasStrictFDerivAt_cpow (x, y) hp #align complex.has_strict_fderiv_at_cpow' Complex.hasStrictFDerivAt_cpow'
Mathlib/Analysis/SpecialFunctions/Pow/Deriv.lean
52
60
theorem hasStrictDerivAt_const_cpow {x y : ℂ} (h : x ≠ 0 ∨ y ≠ 0) : HasStrictDerivAt (fun y => x ^ y) (x ^ y * log x) y := by rcases em (x = 0) with (rfl | hx)
rcases em (x = 0) with (rfl | hx) · replace h := h.neg_resolve_left rfl rw [log_zero, mul_zero] refine (hasStrictDerivAt_const _ 0).congr_of_eventuallyEq ?_ exact (isOpen_ne.eventually_mem h).mono fun y hy => (zero_cpow hy).symm · simpa only [cpow_def_of_ne_zero hx, mul_one] using ((hasStrictDerivAt_id y).const_mul (log x)).cexp
true
import Mathlib.Algebra.GradedMonoid import Mathlib.Algebra.Order.Monoid.Canonical.Defs import Mathlib.Algebra.MvPolynomial.Basic #align_import ring_theory.mv_polynomial.weighted_homogeneous from "leanprover-community/mathlib"@"2f5b500a507264de86d666a5f87ddb976e2d8de4" noncomputable section open Set Function Finset Finsupp AddMonoidAlgebra variable {R M : Type*} [CommSemiring R] namespace MvPolynomial variable {σ : Type*} section AddCommMonoid variable [AddCommMonoid M] def weightedDegree (w : σ → M) : (σ →₀ ℕ) →+ M := (Finsupp.total σ M ℕ w).toAddMonoidHom #align mv_polynomial.weighted_degree' MvPolynomial.weightedDegree theorem weightedDegree_apply (w : σ → M) (f : σ →₀ ℕ): weightedDegree w f = Finsupp.sum f (fun i c => c • w i) := by rfl section SemilatticeSup variable [SemilatticeSup M] def weightedTotalDegree' (w : σ → M) (p : MvPolynomial σ R) : WithBot M := p.support.sup fun s => weightedDegree w s #align mv_polynomial.weighted_total_degree' MvPolynomial.weightedTotalDegree' theorem weightedTotalDegree'_eq_bot_iff (w : σ → M) (p : MvPolynomial σ R) : weightedTotalDegree' w p = ⊥ ↔ p = 0 := by simp only [weightedTotalDegree', Finset.sup_eq_bot_iff, mem_support_iff, WithBot.coe_ne_bot, MvPolynomial.eq_zero_iff] exact forall_congr' fun _ => Classical.not_not #align mv_polynomial.weighted_total_degree'_eq_bot_iff MvPolynomial.weightedTotalDegree'_eq_bot_iff theorem weightedTotalDegree'_zero (w : σ → M) : weightedTotalDegree' w (0 : MvPolynomial σ R) = ⊥ := by simp only [weightedTotalDegree', support_zero, Finset.sup_empty] #align mv_polynomial.weighted_total_degree'_zero MvPolynomial.weightedTotalDegree'_zero def IsWeightedHomogeneous (w : σ → M) (φ : MvPolynomial σ R) (m : M) : Prop := ∀ ⦃d⦄, coeff d φ ≠ 0 → weightedDegree w d = m #align mv_polynomial.is_weighted_homogeneous MvPolynomial.IsWeightedHomogeneous variable (R) def weightedHomogeneousSubmodule (w : σ → M) (m : M) : Submodule R (MvPolynomial σ R) where carrier := { x | x.IsWeightedHomogeneous w m } smul_mem' r a ha c hc := by rw [coeff_smul] at hc exact ha (right_ne_zero_of_mul hc) zero_mem' d hd := False.elim (hd <| coeff_zero _) add_mem' {a} {b} ha hb c hc := by rw [coeff_add] at hc obtain h | h : coeff c a ≠ 0 ∨ coeff c b ≠ 0 := by contrapose! hc simp only [hc, add_zero] · exact ha h · exact hb h #align mv_polynomial.weighted_homogeneous_submodule MvPolynomial.weightedHomogeneousSubmodule @[simp] theorem mem_weightedHomogeneousSubmodule (w : σ → M) (m : M) (p : MvPolynomial σ R) : p ∈ weightedHomogeneousSubmodule R w m ↔ p.IsWeightedHomogeneous w m := Iff.rfl #align mv_polynomial.mem_weighted_homogeneous_submodule MvPolynomial.mem_weightedHomogeneousSubmodule theorem weightedHomogeneousSubmodule_eq_finsupp_supported (w : σ → M) (m : M) : weightedHomogeneousSubmodule R w m = Finsupp.supported R R { d | weightedDegree w d = m } := by ext x rw [mem_supported, Set.subset_def] simp only [Finsupp.mem_support_iff, mem_coe] rfl #align mv_polynomial.weighted_homogeneous_submodule_eq_finsupp_supported MvPolynomial.weightedHomogeneousSubmodule_eq_finsupp_supported variable {R}
Mathlib/RingTheory/MvPolynomial/WeightedHomogeneous.lean
180
192
theorem weightedHomogeneousSubmodule_mul (w : σ → M) (m n : M) : weightedHomogeneousSubmodule R w m * weightedHomogeneousSubmodule R w n ≤ weightedHomogeneousSubmodule R w (m + n) := by classical
classical rw [Submodule.mul_le] intro φ hφ ψ hψ c hc rw [coeff_mul] at hc obtain ⟨⟨d, e⟩, hde, H⟩ := Finset.exists_ne_zero_of_sum_ne_zero hc have aux : coeff d φ ≠ 0 ∧ coeff e ψ ≠ 0 := by contrapose! H by_cases h : coeff d φ = 0 <;> simp_all only [Ne, not_false_iff, zero_mul, mul_zero] rw [← mem_antidiagonal.mp hde, ← hφ aux.1, ← hψ aux.2, map_add]
true
import Mathlib.Geometry.Euclidean.Angle.Oriented.Affine import Mathlib.Geometry.Euclidean.Angle.Unoriented.Affine import Mathlib.Tactic.IntervalCases #align_import geometry.euclidean.triangle from "leanprover-community/mathlib"@"46b633fd842bef9469441c0209906f6dddd2b4f5" noncomputable section open scoped Classical open scoped Real open scoped RealInnerProductSpace namespace InnerProductGeometry variable {V : Type*} [NormedAddCommGroup V] [InnerProductSpace ℝ V] theorem norm_sub_sq_eq_norm_sq_add_norm_sq_sub_two_mul_norm_mul_norm_mul_cos_angle (x y : V) : ‖x - y‖ * ‖x - y‖ = ‖x‖ * ‖x‖ + ‖y‖ * ‖y‖ - 2 * ‖x‖ * ‖y‖ * Real.cos (angle x y) := by rw [show 2 * ‖x‖ * ‖y‖ * Real.cos (angle x y) = 2 * (Real.cos (angle x y) * (‖x‖ * ‖y‖)) by ring, cos_angle_mul_norm_mul_norm, ← real_inner_self_eq_norm_mul_norm, ← real_inner_self_eq_norm_mul_norm, ← real_inner_self_eq_norm_mul_norm, real_inner_sub_sub_self, sub_add_eq_add_sub] #align inner_product_geometry.norm_sub_sq_eq_norm_sq_add_norm_sq_sub_two_mul_norm_mul_norm_mul_cos_angle InnerProductGeometry.norm_sub_sq_eq_norm_sq_add_norm_sq_sub_two_mul_norm_mul_norm_mul_cos_angle theorem angle_sub_eq_angle_sub_rev_of_norm_eq {x y : V} (h : ‖x‖ = ‖y‖) : angle x (x - y) = angle y (y - x) := by refine Real.injOn_cos ⟨angle_nonneg _ _, angle_le_pi _ _⟩ ⟨angle_nonneg _ _, angle_le_pi _ _⟩ ?_ rw [cos_angle, cos_angle, h, ← neg_sub, norm_neg, neg_sub, inner_sub_right, inner_sub_right, real_inner_self_eq_norm_mul_norm, real_inner_self_eq_norm_mul_norm, h, real_inner_comm x y] #align inner_product_geometry.angle_sub_eq_angle_sub_rev_of_norm_eq InnerProductGeometry.angle_sub_eq_angle_sub_rev_of_norm_eq theorem norm_eq_of_angle_sub_eq_angle_sub_rev_of_angle_ne_pi {x y : V} (h : angle x (x - y) = angle y (y - x)) (hpi : angle x y ≠ π) : ‖x‖ = ‖y‖ := by replace h := Real.arccos_injOn (abs_le.mp (abs_real_inner_div_norm_mul_norm_le_one x (x - y))) (abs_le.mp (abs_real_inner_div_norm_mul_norm_le_one y (y - x))) h by_cases hxy : x = y · rw [hxy] · rw [← norm_neg (y - x), neg_sub, mul_comm, mul_comm ‖y‖, div_eq_mul_inv, div_eq_mul_inv, mul_inv_rev, mul_inv_rev, ← mul_assoc, ← mul_assoc] at h replace h := mul_right_cancel₀ (inv_ne_zero fun hz => hxy (eq_of_sub_eq_zero (norm_eq_zero.1 hz))) h rw [inner_sub_right, inner_sub_right, real_inner_comm x y, real_inner_self_eq_norm_mul_norm, real_inner_self_eq_norm_mul_norm, mul_sub_right_distrib, mul_sub_right_distrib, mul_self_mul_inv, mul_self_mul_inv, sub_eq_sub_iff_sub_eq_sub, ← mul_sub_left_distrib] at h by_cases hx0 : x = 0 · rw [hx0, norm_zero, inner_zero_left, zero_mul, zero_sub, neg_eq_zero] at h rw [hx0, norm_zero, h] · by_cases hy0 : y = 0 · rw [hy0, norm_zero, inner_zero_right, zero_mul, sub_zero] at h rw [hy0, norm_zero, h] · rw [inv_sub_inv (fun hz => hx0 (norm_eq_zero.1 hz)) fun hz => hy0 (norm_eq_zero.1 hz), ← neg_sub, ← mul_div_assoc, mul_comm, mul_div_assoc, ← mul_neg_one] at h symm by_contra hyx replace h := (mul_left_cancel₀ (sub_ne_zero_of_ne hyx) h).symm rw [real_inner_div_norm_mul_norm_eq_neg_one_iff, ← angle_eq_pi_iff] at h exact hpi h #align inner_product_geometry.norm_eq_of_angle_sub_eq_angle_sub_rev_of_angle_ne_pi InnerProductGeometry.norm_eq_of_angle_sub_eq_angle_sub_rev_of_angle_ne_pi
Mathlib/Geometry/Euclidean/Triangle.lean
109
143
theorem cos_angle_sub_add_angle_sub_rev_eq_neg_cos_angle {x y : V} (hx : x ≠ 0) (hy : y ≠ 0) : Real.cos (angle x (x - y) + angle y (y - x)) = -Real.cos (angle x y) := by by_cases hxy : x = y
by_cases hxy : x = y · rw [hxy, angle_self hy] simp · rw [Real.cos_add, cos_angle, cos_angle, cos_angle] have hxn : ‖x‖ ≠ 0 := fun h => hx (norm_eq_zero.1 h) have hyn : ‖y‖ ≠ 0 := fun h => hy (norm_eq_zero.1 h) have hxyn : ‖x - y‖ ≠ 0 := fun h => hxy (eq_of_sub_eq_zero (norm_eq_zero.1 h)) apply mul_right_cancel₀ hxn apply mul_right_cancel₀ hyn apply mul_right_cancel₀ hxyn apply mul_right_cancel₀ hxyn have H1 : Real.sin (angle x (x - y)) * Real.sin (angle y (y - x)) * ‖x‖ * ‖y‖ * ‖x - y‖ * ‖x - y‖ = Real.sin (angle x (x - y)) * (‖x‖ * ‖x - y‖) * (Real.sin (angle y (y - x)) * (‖y‖ * ‖x - y‖)) := by ring have H2 : ⟪x, x⟫ * (⟪x, x⟫ - ⟪x, y⟫ - (⟪x, y⟫ - ⟪y, y⟫)) - (⟪x, x⟫ - ⟪x, y⟫) * (⟪x, x⟫ - ⟪x, y⟫) = ⟪x, x⟫ * ⟪y, y⟫ - ⟪x, y⟫ * ⟪x, y⟫ := by ring have H3 : ⟪y, y⟫ * (⟪y, y⟫ - ⟪x, y⟫ - (⟪x, y⟫ - ⟪x, x⟫)) - (⟪y, y⟫ - ⟪x, y⟫) * (⟪y, y⟫ - ⟪x, y⟫) = ⟪x, x⟫ * ⟪y, y⟫ - ⟪x, y⟫ * ⟪x, y⟫ := by ring rw [mul_sub_right_distrib, mul_sub_right_distrib, mul_sub_right_distrib, mul_sub_right_distrib, H1, sin_angle_mul_norm_mul_norm, norm_sub_rev x y, sin_angle_mul_norm_mul_norm, norm_sub_rev y x, inner_sub_left, inner_sub_left, inner_sub_right, inner_sub_right, inner_sub_right, inner_sub_right, real_inner_comm x y, H2, H3, Real.mul_self_sqrt (sub_nonneg_of_le (real_inner_mul_inner_self_le x y)), real_inner_self_eq_norm_mul_norm, real_inner_self_eq_norm_mul_norm, real_inner_eq_norm_mul_self_add_norm_mul_self_sub_norm_sub_mul_self_div_two] field_simp [hxn, hyn, hxyn] ring
true
import Mathlib.RingTheory.MvPowerSeries.Basic import Mathlib.Data.Finsupp.Interval noncomputable section open Finset (antidiagonal mem_antidiagonal) namespace MvPowerSeries open Finsupp variable {σ R : Type*} section Trunc variable [CommSemiring R] (n : σ →₀ ℕ) def truncFun (φ : MvPowerSeries σ R) : MvPolynomial σ R := ∑ m ∈ Finset.Iio n, MvPolynomial.monomial m (coeff R m φ) #align mv_power_series.trunc_fun MvPowerSeries.truncFun theorem coeff_truncFun (m : σ →₀ ℕ) (φ : MvPowerSeries σ R) : (truncFun n φ).coeff m = if m < n then coeff R m φ else 0 := by classical simp [truncFun, MvPolynomial.coeff_sum] #align mv_power_series.coeff_trunc_fun MvPowerSeries.coeff_truncFun variable (R) def trunc : MvPowerSeries σ R →+ MvPolynomial σ R where toFun := truncFun n map_zero' := by classical ext simp [coeff_truncFun] map_add' := by classical intros x y ext m simp only [coeff_truncFun, MvPolynomial.coeff_add] split_ifs · rw [map_add] · rw [zero_add] #align mv_power_series.trunc MvPowerSeries.trunc variable {R}
Mathlib/RingTheory/MvPowerSeries/Trunc.lean
71
73
theorem coeff_trunc (m : σ →₀ ℕ) (φ : MvPowerSeries σ R) : (trunc R n φ).coeff m = if m < n then coeff R m φ else 0 := by
classical simp [trunc, coeff_truncFun]
true
import Mathlib.SetTheory.Game.Ordinal import Mathlib.SetTheory.Ordinal.NaturalOps #align_import set_theory.game.birthday from "leanprover-community/mathlib"@"a347076985674932c0e91da09b9961ed0a79508c" universe u open Ordinal namespace SetTheory open scoped NaturalOps PGame namespace PGame noncomputable def birthday : PGame.{u} → Ordinal.{u} | ⟨_, _, xL, xR⟩ => max (lsub.{u, u} fun i => birthday (xL i)) (lsub.{u, u} fun i => birthday (xR i)) #align pgame.birthday SetTheory.PGame.birthday theorem birthday_def (x : PGame) : birthday x = max (lsub.{u, u} fun i => birthday (x.moveLeft i)) (lsub.{u, u} fun i => birthday (x.moveRight i)) := by cases x; rw [birthday]; rfl #align pgame.birthday_def SetTheory.PGame.birthday_def theorem birthday_moveLeft_lt {x : PGame} (i : x.LeftMoves) : (x.moveLeft i).birthday < x.birthday := by cases x; rw [birthday]; exact lt_max_of_lt_left (lt_lsub _ i) #align pgame.birthday_move_left_lt SetTheory.PGame.birthday_moveLeft_lt theorem birthday_moveRight_lt {x : PGame} (i : x.RightMoves) : (x.moveRight i).birthday < x.birthday := by cases x; rw [birthday]; exact lt_max_of_lt_right (lt_lsub _ i) #align pgame.birthday_move_right_lt SetTheory.PGame.birthday_moveRight_lt
Mathlib/SetTheory/Game/Birthday.lean
64
78
theorem lt_birthday_iff {x : PGame} {o : Ordinal} : o < x.birthday ↔ (∃ i : x.LeftMoves, o ≤ (x.moveLeft i).birthday) ∨ ∃ i : x.RightMoves, o ≤ (x.moveRight i).birthday := by constructor
constructor · rw [birthday_def] intro h cases' lt_max_iff.1 h with h' h' · left rwa [lt_lsub_iff] at h' · right rwa [lt_lsub_iff] at h' · rintro (⟨i, hi⟩ | ⟨i, hi⟩) · exact hi.trans_lt (birthday_moveLeft_lt i) · exact hi.trans_lt (birthday_moveRight_lt i)
true
import Mathlib.RingTheory.Algebraic import Mathlib.RingTheory.Localization.AtPrime import Mathlib.RingTheory.Localization.Integral #align_import ring_theory.ideal.over from "leanprover-community/mathlib"@"198cb64d5c961e1a8d0d3e219feb7058d5353861" variable {R : Type*} [CommRing R] namespace Ideal open Polynomial open Polynomial open Submodule section CommRing variable {S : Type*} [CommRing S] {f : R →+* S} {I J : Ideal S} theorem coeff_zero_mem_comap_of_root_mem_of_eval_mem {r : S} (hr : r ∈ I) {p : R[X]} (hp : p.eval₂ f r ∈ I) : p.coeff 0 ∈ I.comap f := by rw [← p.divX_mul_X_add, eval₂_add, eval₂_C, eval₂_mul, eval₂_X] at hp refine mem_comap.mpr ((I.add_mem_iff_right ?_).mp hp) exact I.mul_mem_left _ hr #align ideal.coeff_zero_mem_comap_of_root_mem_of_eval_mem Ideal.coeff_zero_mem_comap_of_root_mem_of_eval_mem theorem coeff_zero_mem_comap_of_root_mem {r : S} (hr : r ∈ I) {p : R[X]} (hp : p.eval₂ f r = 0) : p.coeff 0 ∈ I.comap f := coeff_zero_mem_comap_of_root_mem_of_eval_mem hr (hp.symm ▸ I.zero_mem) #align ideal.coeff_zero_mem_comap_of_root_mem Ideal.coeff_zero_mem_comap_of_root_mem theorem exists_coeff_ne_zero_mem_comap_of_non_zero_divisor_root_mem {r : S} (r_non_zero_divisor : ∀ {x}, x * r = 0 → x = 0) (hr : r ∈ I) {p : R[X]} : p ≠ 0 → p.eval₂ f r = 0 → ∃ i, p.coeff i ≠ 0 ∧ p.coeff i ∈ I.comap f := by refine p.recOnHorner ?_ ?_ ?_ · intro h contradiction · intro p a coeff_eq_zero a_ne_zero _ _ hp refine ⟨0, ?_, coeff_zero_mem_comap_of_root_mem hr hp⟩ simp [coeff_eq_zero, a_ne_zero] · intro p p_nonzero ih _ hp rw [eval₂_mul, eval₂_X] at hp obtain ⟨i, hi, mem⟩ := ih p_nonzero (r_non_zero_divisor hp) refine ⟨i + 1, ?_, ?_⟩ · simp [hi, mem] · simpa [hi] using mem #align ideal.exists_coeff_ne_zero_mem_comap_of_non_zero_divisor_root_mem Ideal.exists_coeff_ne_zero_mem_comap_of_non_zero_divisor_root_mem theorem injective_quotient_le_comap_map (P : Ideal R[X]) : Function.Injective <| Ideal.quotientMap (Ideal.map (Polynomial.mapRingHom (Quotient.mk (P.comap (C : R →+* R[X])))) P) (Polynomial.mapRingHom (Ideal.Quotient.mk (P.comap (C : R →+* R[X])))) le_comap_map := by refine quotientMap_injective' (le_of_eq ?_) rw [comap_map_of_surjective (mapRingHom (Ideal.Quotient.mk (P.comap (C : R →+* R[X])))) (map_surjective (Ideal.Quotient.mk (P.comap (C : R →+* R[X]))) Ideal.Quotient.mk_surjective)] refine le_antisymm (sup_le le_rfl ?_) (le_sup_of_le_left le_rfl) refine fun p hp => polynomial_mem_ideal_of_coeff_mem_ideal P p fun n => Ideal.Quotient.eq_zero_iff_mem.mp ?_ simpa only [coeff_map, coe_mapRingHom] using ext_iff.mp (Ideal.mem_bot.mp (mem_comap.mp hp)) n #align ideal.injective_quotient_le_comap_map Ideal.injective_quotient_le_comap_map theorem quotient_mk_maps_eq (P : Ideal R[X]) : ((Quotient.mk (map (mapRingHom (Quotient.mk (P.comap (C : R →+* R[X])))) P)).comp C).comp (Quotient.mk (P.comap (C : R →+* R[X]))) = (Ideal.quotientMap (map (mapRingHom (Quotient.mk (P.comap (C : R →+* R[X])))) P) (mapRingHom (Quotient.mk (P.comap (C : R →+* R[X])))) le_comap_map).comp ((Quotient.mk P).comp C) := by refine RingHom.ext fun x => ?_ repeat' rw [RingHom.coe_comp, Function.comp_apply] rw [quotientMap_mk, coe_mapRingHom, map_C] #align ideal.quotient_mk_maps_eq Ideal.quotient_mk_maps_eq theorem exists_nonzero_mem_of_ne_bot {P : Ideal R[X]} (Pb : P ≠ ⊥) (hP : ∀ x : R, C x ∈ P → x = 0) : ∃ p : R[X], p ∈ P ∧ Polynomial.map (Quotient.mk (P.comap (C : R →+* R[X]))) p ≠ 0 := by obtain ⟨m, hm⟩ := Submodule.nonzero_mem_of_bot_lt (bot_lt_iff_ne_bot.mpr Pb) refine ⟨m, Submodule.coe_mem m, fun pp0 => hm (Submodule.coe_eq_zero.mp ?_)⟩ refine (injective_iff_map_eq_zero (Polynomial.mapRingHom (Ideal.Quotient.mk (P.comap (C : R →+* R[X]))))).mp ?_ _ pp0 refine map_injective _ ((Ideal.Quotient.mk (P.comap C)).injective_iff_ker_eq_bot.mpr ?_) rw [mk_ker] exact (Submodule.eq_bot_iff _).mpr fun x hx => hP x (mem_comap.mp hx) #align ideal.exists_nonzero_mem_of_ne_bot Ideal.exists_nonzero_mem_of_ne_bot variable {p : Ideal R} {P : Ideal S}
Mathlib/RingTheory/Ideal/Over.lean
139
149
theorem comap_eq_of_scalar_tower_quotient [Algebra R S] [Algebra (R ⧸ p) (S ⧸ P)] [IsScalarTower R (R ⧸ p) (S ⧸ P)] (h : Function.Injective (algebraMap (R ⧸ p) (S ⧸ P))) : comap (algebraMap R S) P = p := by ext x
ext x rw [mem_comap, ← Quotient.eq_zero_iff_mem, ← Quotient.eq_zero_iff_mem, Quotient.mk_algebraMap, IsScalarTower.algebraMap_apply R (R ⧸ p) (S ⧸ P), Quotient.algebraMap_eq] constructor · intro hx exact (injective_iff_map_eq_zero (algebraMap (R ⧸ p) (S ⧸ P))).mp h _ hx · intro hx rw [hx, RingHom.map_zero]
true
import Mathlib.Algebra.Homology.ShortComplex.ModuleCat import Mathlib.RepresentationTheory.GroupCohomology.Basic import Mathlib.RepresentationTheory.Invariants universe v u noncomputable section open CategoryTheory Limits Representation variable {k G : Type u} [CommRing k] [Group G] (A : Rep k G) namespace groupCohomology section IsCocycle section variable {G A : Type*} [Mul G] [AddCommGroup A] [SMul G A] def IsOneCocycle (f : G → A) : Prop := ∀ g h : G, f (g * h) = g • f h + f g def IsTwoCocycle (f : G × G → A) : Prop := ∀ g h j : G, f (g * h, j) + f (g, h) = g • (f (h, j)) + f (g, h * j) end section variable {G A : Type*} [Monoid G] [AddCommGroup A] [MulAction G A] theorem map_one_of_isOneCocycle {f : G → A} (hf : IsOneCocycle f) : f 1 = 0 := by simpa only [mul_one, one_smul, self_eq_add_right] using hf 1 1
Mathlib/RepresentationTheory/GroupCohomology/LowDegree.lean
405
407
theorem map_one_fst_of_isTwoCocycle {f : G × G → A} (hf : IsTwoCocycle f) (g : G) : f (1, g) = f (1, 1) := by
simpa only [one_smul, one_mul, mul_one, add_right_inj] using (hf 1 1 g).symm
true
import Mathlib.Data.Set.Prod import Mathlib.Logic.Function.Conjugate #align_import data.set.function from "leanprover-community/mathlib"@"996b0ff959da753a555053a480f36e5f264d4207" variable {α β γ : Type*} {ι : Sort*} {π : α → Type*} open Equiv Equiv.Perm Function namespace Set section restrict def restrict (s : Set α) (f : ∀ a : α, π a) : ∀ a : s, π a := fun x => f x #align set.restrict Set.restrict theorem restrict_eq (f : α → β) (s : Set α) : s.restrict f = f ∘ Subtype.val := rfl #align set.restrict_eq Set.restrict_eq @[simp] theorem restrict_apply (f : α → β) (s : Set α) (x : s) : s.restrict f x = f x := rfl #align set.restrict_apply Set.restrict_apply theorem restrict_eq_iff {f : ∀ a, π a} {s : Set α} {g : ∀ a : s, π a} : restrict s f = g ↔ ∀ (a) (ha : a ∈ s), f a = g ⟨a, ha⟩ := funext_iff.trans Subtype.forall #align set.restrict_eq_iff Set.restrict_eq_iff theorem eq_restrict_iff {s : Set α} {f : ∀ a : s, π a} {g : ∀ a, π a} : f = restrict s g ↔ ∀ (a) (ha : a ∈ s), f ⟨a, ha⟩ = g a := funext_iff.trans Subtype.forall #align set.eq_restrict_iff Set.eq_restrict_iff @[simp] theorem range_restrict (f : α → β) (s : Set α) : Set.range (s.restrict f) = f '' s := (range_comp _ _).trans <| congr_arg (f '' ·) Subtype.range_coe #align set.range_restrict Set.range_restrict theorem image_restrict (f : α → β) (s t : Set α) : s.restrict f '' (Subtype.val ⁻¹' t) = f '' (t ∩ s) := by rw [restrict_eq, image_comp, image_preimage_eq_inter_range, Subtype.range_coe] #align set.image_restrict Set.image_restrict @[simp] theorem restrict_dite {s : Set α} [∀ x, Decidable (x ∈ s)] (f : ∀ a ∈ s, β) (g : ∀ a ∉ s, β) : (s.restrict fun a => if h : a ∈ s then f a h else g a h) = (fun a : s => f a a.2) := funext fun a => dif_pos a.2 #align set.restrict_dite Set.restrict_dite @[simp] theorem restrict_dite_compl {s : Set α} [∀ x, Decidable (x ∈ s)] (f : ∀ a ∈ s, β) (g : ∀ a ∉ s, β) : (sᶜ.restrict fun a => if h : a ∈ s then f a h else g a h) = (fun a : (sᶜ : Set α) => g a a.2) := funext fun a => dif_neg a.2 #align set.restrict_dite_compl Set.restrict_dite_compl @[simp] theorem restrict_ite (f g : α → β) (s : Set α) [∀ x, Decidable (x ∈ s)] : (s.restrict fun a => if a ∈ s then f a else g a) = s.restrict f := restrict_dite _ _ #align set.restrict_ite Set.restrict_ite @[simp] theorem restrict_ite_compl (f g : α → β) (s : Set α) [∀ x, Decidable (x ∈ s)] : (sᶜ.restrict fun a => if a ∈ s then f a else g a) = sᶜ.restrict g := restrict_dite_compl _ _ #align set.restrict_ite_compl Set.restrict_ite_compl @[simp] theorem restrict_piecewise (f g : α → β) (s : Set α) [∀ x, Decidable (x ∈ s)] : s.restrict (piecewise s f g) = s.restrict f := restrict_ite _ _ _ #align set.restrict_piecewise Set.restrict_piecewise @[simp] theorem restrict_piecewise_compl (f g : α → β) (s : Set α) [∀ x, Decidable (x ∈ s)] : sᶜ.restrict (piecewise s f g) = sᶜ.restrict g := restrict_ite_compl _ _ _ #align set.restrict_piecewise_compl Set.restrict_piecewise_compl
Mathlib/Data/Set/Function.lean
117
120
theorem restrict_extend_range (f : α → β) (g : α → γ) (g' : β → γ) : (range f).restrict (extend f g g') = fun x => g x.coe_prop.choose := by classical
classical exact restrict_dite _ _
true
import Mathlib.LinearAlgebra.Ray import Mathlib.Analysis.NormedSpace.Real #align_import analysis.normed_space.ray from "leanprover-community/mathlib"@"92ca63f0fb391a9ca5f22d2409a6080e786d99f7" open Real variable {E : Type*} [SeminormedAddCommGroup E] [NormedSpace ℝ E] {F : Type*} [NormedAddCommGroup F] [NormedSpace ℝ F] variable {x y : F} theorem norm_injOn_ray_left (hx : x ≠ 0) : { y | SameRay ℝ x y }.InjOn norm := by rintro y hy z hz h rcases hy.exists_nonneg_left hx with ⟨r, hr, rfl⟩ rcases hz.exists_nonneg_left hx with ⟨s, hs, rfl⟩ rw [norm_smul, norm_smul, mul_left_inj' (norm_ne_zero_iff.2 hx), norm_of_nonneg hr, norm_of_nonneg hs] at h rw [h] #align norm_inj_on_ray_left norm_injOn_ray_left
Mathlib/Analysis/NormedSpace/Ray.lean
68
69
theorem norm_injOn_ray_right (hy : y ≠ 0) : { x | SameRay ℝ x y }.InjOn norm := by
simpa only [SameRay.sameRay_comm] using norm_injOn_ray_left hy
true
import Mathlib.Algebra.Polynomial.AlgebraMap import Mathlib.Algebra.Polynomial.Degree.Lemmas import Mathlib.Algebra.Polynomial.HasseDeriv #align_import data.polynomial.taylor from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a" noncomputable section namespace Polynomial open Polynomial variable {R : Type*} [Semiring R] (r : R) (f : R[X]) def taylor (r : R) : R[X] →ₗ[R] R[X] where toFun f := f.comp (X + C r) map_add' f g := add_comp map_smul' c f := by simp only [smul_eq_C_mul, C_mul_comp, RingHom.id_apply] #align polynomial.taylor Polynomial.taylor theorem taylor_apply : taylor r f = f.comp (X + C r) := rfl #align polynomial.taylor_apply Polynomial.taylor_apply @[simp] theorem taylor_X : taylor r X = X + C r := by simp only [taylor_apply, X_comp] set_option linter.uppercaseLean3 false in #align polynomial.taylor_X Polynomial.taylor_X @[simp] theorem taylor_C (x : R) : taylor r (C x) = C x := by simp only [taylor_apply, C_comp] set_option linter.uppercaseLean3 false in #align polynomial.taylor_C Polynomial.taylor_C @[simp]
Mathlib/Algebra/Polynomial/Taylor.lean
56
59
theorem taylor_zero' : taylor (0 : R) = LinearMap.id := by ext
ext simp only [taylor_apply, add_zero, comp_X, _root_.map_zero, LinearMap.id_comp, Function.comp_apply, LinearMap.coe_comp]
true
import Mathlib.Analysis.NormedSpace.HahnBanach.Extension import Mathlib.Analysis.NormedSpace.RCLike import Mathlib.Analysis.LocallyConvex.Polar #align_import analysis.normed_space.dual from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982" noncomputable section open scoped Classical open Topology Bornology universe u v namespace NormedSpace section General variable (𝕜 : Type*) [NontriviallyNormedField 𝕜] variable (E : Type*) [SeminormedAddCommGroup E] [NormedSpace 𝕜 E] variable (F : Type*) [NormedAddCommGroup F] [NormedSpace 𝕜 F] abbrev Dual : Type _ := E →L[𝕜] 𝕜 #align normed_space.dual NormedSpace.Dual -- TODO: helper instance for elaboration of inclusionInDoubleDual_norm_eq until -- leanprover/lean4#2522 is resolved; remove once fixed instance : NormedSpace 𝕜 (Dual 𝕜 E) := inferInstance -- TODO: helper instance for elaboration of inclusionInDoubleDual_norm_le until -- leanprover/lean4#2522 is resolved; remove once fixed instance : SeminormedAddCommGroup (Dual 𝕜 E) := inferInstance def inclusionInDoubleDual : E →L[𝕜] Dual 𝕜 (Dual 𝕜 E) := ContinuousLinearMap.apply 𝕜 𝕜 #align normed_space.inclusion_in_double_dual NormedSpace.inclusionInDoubleDual @[simp] theorem dual_def (x : E) (f : Dual 𝕜 E) : inclusionInDoubleDual 𝕜 E x f = f x := rfl #align normed_space.dual_def NormedSpace.dual_def theorem inclusionInDoubleDual_norm_eq : ‖inclusionInDoubleDual 𝕜 E‖ = ‖ContinuousLinearMap.id 𝕜 (Dual 𝕜 E)‖ := ContinuousLinearMap.opNorm_flip _ #align normed_space.inclusion_in_double_dual_norm_eq NormedSpace.inclusionInDoubleDual_norm_eq
Mathlib/Analysis/NormedSpace/Dual.lean
82
84
theorem inclusionInDoubleDual_norm_le : ‖inclusionInDoubleDual 𝕜 E‖ ≤ 1 := by rw [inclusionInDoubleDual_norm_eq]
rw [inclusionInDoubleDual_norm_eq] exact ContinuousLinearMap.norm_id_le
true
import Mathlib.Dynamics.Ergodic.MeasurePreserving import Mathlib.LinearAlgebra.Determinant import Mathlib.LinearAlgebra.Matrix.Diagonal import Mathlib.LinearAlgebra.Matrix.Transvection import Mathlib.MeasureTheory.Group.LIntegral import Mathlib.MeasureTheory.Integral.Marginal import Mathlib.MeasureTheory.Measure.Stieltjes import Mathlib.MeasureTheory.Measure.Haar.OfBasis #align_import measure_theory.measure.lebesgue.basic from "leanprover-community/mathlib"@"fd5edc43dc4f10b85abfe544b88f82cf13c5f844" assert_not_exists MeasureTheory.integral noncomputable section open scoped Classical open Set Filter MeasureTheory MeasureTheory.Measure TopologicalSpace open ENNReal (ofReal) open scoped ENNReal NNReal Topology namespace Real variable {ι : Type*} [Fintype ι] theorem volume_eq_stieltjes_id : (volume : Measure ℝ) = StieltjesFunction.id.measure := by haveI : IsAddLeftInvariant StieltjesFunction.id.measure := ⟨fun a => Eq.symm <| Real.measure_ext_Ioo_rat fun p q => by simp only [Measure.map_apply (measurable_const_add a) measurableSet_Ioo, sub_sub_sub_cancel_right, StieltjesFunction.measure_Ioo, StieltjesFunction.id_leftLim, StieltjesFunction.id_apply, id, preimage_const_add_Ioo]⟩ have A : StieltjesFunction.id.measure (stdOrthonormalBasis ℝ ℝ).toBasis.parallelepiped = 1 := by change StieltjesFunction.id.measure (parallelepiped (stdOrthonormalBasis ℝ ℝ)) = 1 rcases parallelepiped_orthonormalBasis_one_dim (stdOrthonormalBasis ℝ ℝ) with (H | H) <;> simp only [H, StieltjesFunction.measure_Icc, StieltjesFunction.id_apply, id, tsub_zero, StieltjesFunction.id_leftLim, sub_neg_eq_add, zero_add, ENNReal.ofReal_one] conv_rhs => rw [addHaarMeasure_unique StieltjesFunction.id.measure (stdOrthonormalBasis ℝ ℝ).toBasis.parallelepiped, A] simp only [volume, Basis.addHaar, one_smul] #align real.volume_eq_stieltjes_id Real.volume_eq_stieltjes_id theorem volume_val (s) : volume s = StieltjesFunction.id.measure s := by simp [volume_eq_stieltjes_id] #align real.volume_val Real.volume_val @[simp] theorem volume_Ico {a b : ℝ} : volume (Ico a b) = ofReal (b - a) := by simp [volume_val] #align real.volume_Ico Real.volume_Ico @[simp] theorem volume_Icc {a b : ℝ} : volume (Icc a b) = ofReal (b - a) := by simp [volume_val] #align real.volume_Icc Real.volume_Icc @[simp] theorem volume_Ioo {a b : ℝ} : volume (Ioo a b) = ofReal (b - a) := by simp [volume_val] #align real.volume_Ioo Real.volume_Ioo @[simp] theorem volume_Ioc {a b : ℝ} : volume (Ioc a b) = ofReal (b - a) := by simp [volume_val] #align real.volume_Ioc Real.volume_Ioc -- @[simp] -- Porting note (#10618): simp can prove this theorem volume_singleton {a : ℝ} : volume ({a} : Set ℝ) = 0 := by simp [volume_val] #align real.volume_singleton Real.volume_singleton -- @[simp] -- Porting note (#10618): simp can prove this, after mathlib4#4628 theorem volume_univ : volume (univ : Set ℝ) = ∞ := ENNReal.eq_top_of_forall_nnreal_le fun r => calc (r : ℝ≥0∞) = volume (Icc (0 : ℝ) r) := by simp _ ≤ volume univ := measure_mono (subset_univ _) #align real.volume_univ Real.volume_univ @[simp] theorem volume_ball (a r : ℝ) : volume (Metric.ball a r) = ofReal (2 * r) := by rw [ball_eq_Ioo, volume_Ioo, ← sub_add, add_sub_cancel_left, two_mul] #align real.volume_ball Real.volume_ball @[simp] theorem volume_closedBall (a r : ℝ) : volume (Metric.closedBall a r) = ofReal (2 * r) := by rw [closedBall_eq_Icc, volume_Icc, ← sub_add, add_sub_cancel_left, two_mul] #align real.volume_closed_ball Real.volume_closedBall @[simp] theorem volume_emetric_ball (a : ℝ) (r : ℝ≥0∞) : volume (EMetric.ball a r) = 2 * r := by rcases eq_or_ne r ∞ with (rfl | hr) · rw [Metric.emetric_ball_top, volume_univ, two_mul, _root_.top_add] · lift r to ℝ≥0 using hr rw [Metric.emetric_ball_nnreal, volume_ball, two_mul, ← NNReal.coe_add, ENNReal.ofReal_coe_nnreal, ENNReal.coe_add, two_mul] #align real.volume_emetric_ball Real.volume_emetric_ball @[simp]
Mathlib/MeasureTheory/Measure/Lebesgue/Basic.lean
127
132
theorem volume_emetric_closedBall (a : ℝ) (r : ℝ≥0∞) : volume (EMetric.closedBall a r) = 2 * r := by rcases eq_or_ne r ∞ with (rfl | hr)
rcases eq_or_ne r ∞ with (rfl | hr) · rw [EMetric.closedBall_top, volume_univ, two_mul, _root_.top_add] · lift r to ℝ≥0 using hr rw [Metric.emetric_closedBall_nnreal, volume_closedBall, two_mul, ← NNReal.coe_add, ENNReal.ofReal_coe_nnreal, ENNReal.coe_add, two_mul]
true
import Mathlib.Data.List.Infix #align_import data.list.rdrop from "leanprover-community/mathlib"@"26f081a2fb920140ed5bc5cc5344e84bcc7cb2b2" -- Make sure we don't import algebra assert_not_exists Monoid variable {α : Type*} (p : α → Bool) (l : List α) (n : ℕ) namespace List def rdrop : List α := l.take (l.length - n) #align list.rdrop List.rdrop @[simp] theorem rdrop_nil : rdrop ([] : List α) n = [] := by simp [rdrop] #align list.rdrop_nil List.rdrop_nil @[simp]
Mathlib/Data/List/DropRight.lean
51
51
theorem rdrop_zero : rdrop l 0 = l := by
simp [rdrop]
true
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
Mathlib/Data/ENNReal/Real.lean
114
117
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
refine le_trans (toReal_mono' hle ?_) toReal_add_le simpa only [add_eq_top, or_imp] using And.intro hb hc
true
import Mathlib.Order.Interval.Finset.Nat #align_import data.fin.interval from "leanprover-community/mathlib"@"1d29de43a5ba4662dd33b5cfeecfc2a27a5a8a29" assert_not_exists MonoidWithZero open Finset Fin Function namespace Fin variable (n : ℕ) instance instLocallyFiniteOrder : LocallyFiniteOrder (Fin n) := OrderIso.locallyFiniteOrder Fin.orderIsoSubtype instance instLocallyFiniteOrderBot : LocallyFiniteOrderBot (Fin n) := OrderIso.locallyFiniteOrderBot Fin.orderIsoSubtype instance instLocallyFiniteOrderTop : ∀ n, LocallyFiniteOrderTop (Fin n) | 0 => IsEmpty.toLocallyFiniteOrderTop | _ + 1 => inferInstance variable {n} (a b : Fin n) theorem Icc_eq_finset_subtype : Icc a b = (Icc (a : ℕ) b).fin n := rfl #align fin.Icc_eq_finset_subtype Fin.Icc_eq_finset_subtype theorem Ico_eq_finset_subtype : Ico a b = (Ico (a : ℕ) b).fin n := rfl #align fin.Ico_eq_finset_subtype Fin.Ico_eq_finset_subtype theorem Ioc_eq_finset_subtype : Ioc a b = (Ioc (a : ℕ) b).fin n := rfl #align fin.Ioc_eq_finset_subtype Fin.Ioc_eq_finset_subtype theorem Ioo_eq_finset_subtype : Ioo a b = (Ioo (a : ℕ) b).fin n := rfl #align fin.Ioo_eq_finset_subtype Fin.Ioo_eq_finset_subtype theorem uIcc_eq_finset_subtype : uIcc a b = (uIcc (a : ℕ) b).fin n := rfl #align fin.uIcc_eq_finset_subtype Fin.uIcc_eq_finset_subtype @[simp] theorem map_valEmbedding_Icc : (Icc a b).map Fin.valEmbedding = Icc ↑a ↑b := by simp [Icc_eq_finset_subtype, Finset.fin, Finset.map_map, Icc_filter_lt_of_lt_right] #align fin.map_subtype_embedding_Icc Fin.map_valEmbedding_Icc @[simp] theorem map_valEmbedding_Ico : (Ico a b).map Fin.valEmbedding = Ico ↑a ↑b := by simp [Ico_eq_finset_subtype, Finset.fin, Finset.map_map] #align fin.map_subtype_embedding_Ico Fin.map_valEmbedding_Ico @[simp] theorem map_valEmbedding_Ioc : (Ioc a b).map Fin.valEmbedding = Ioc ↑a ↑b := by simp [Ioc_eq_finset_subtype, Finset.fin, Finset.map_map, Ioc_filter_lt_of_lt_right] #align fin.map_subtype_embedding_Ioc Fin.map_valEmbedding_Ioc @[simp] theorem map_valEmbedding_Ioo : (Ioo a b).map Fin.valEmbedding = Ioo ↑a ↑b := by simp [Ioo_eq_finset_subtype, Finset.fin, Finset.map_map] #align fin.map_subtype_embedding_Ioo Fin.map_valEmbedding_Ioo @[simp] theorem map_subtype_embedding_uIcc : (uIcc a b).map valEmbedding = uIcc ↑a ↑b := map_valEmbedding_Icc _ _ #align fin.map_subtype_embedding_uIcc Fin.map_subtype_embedding_uIcc @[simp] theorem card_Icc : (Icc a b).card = b + 1 - a := by rw [← Nat.card_Icc, ← map_valEmbedding_Icc, card_map] #align fin.card_Icc Fin.card_Icc @[simp] theorem card_Ico : (Ico a b).card = b - a := by rw [← Nat.card_Ico, ← map_valEmbedding_Ico, card_map] #align fin.card_Ico Fin.card_Ico @[simp] theorem card_Ioc : (Ioc a b).card = b - a := by rw [← Nat.card_Ioc, ← map_valEmbedding_Ioc, card_map] #align fin.card_Ioc Fin.card_Ioc @[simp] theorem card_Ioo : (Ioo a b).card = b - a - 1 := by rw [← Nat.card_Ioo, ← map_valEmbedding_Ioo, card_map] #align fin.card_Ioo Fin.card_Ioo @[simp]
Mathlib/Order/Interval/Finset/Fin.lean
124
125
theorem card_uIcc : (uIcc a b).card = (b - a : ℤ).natAbs + 1 := by
rw [← Nat.card_uIcc, ← map_subtype_embedding_uIcc, card_map]
true
import Mathlib.Algebra.GroupWithZero.NonZeroDivisors import Mathlib.Algebra.Polynomial.AlgebraMap import Mathlib.RingTheory.Coprime.Basic import Mathlib.Tactic.AdaptationNote #align_import ring_theory.polynomial.scale_roots from "leanprover-community/mathlib"@"40ac1b258344e0c2b4568dc37bfad937ec35a727" variable {R S A K : Type*} namespace Polynomial open Polynomial section Semiring variable [Semiring R] [Semiring S] noncomputable def scaleRoots (p : R[X]) (s : R) : R[X] := ∑ i ∈ p.support, monomial i (p.coeff i * s ^ (p.natDegree - i)) #align polynomial.scale_roots Polynomial.scaleRoots @[simp] theorem coeff_scaleRoots (p : R[X]) (s : R) (i : ℕ) : (scaleRoots p s).coeff i = coeff p i * s ^ (p.natDegree - i) := by simp (config := { contextual := true }) [scaleRoots, coeff_monomial] #align polynomial.coeff_scale_roots Polynomial.coeff_scaleRoots theorem coeff_scaleRoots_natDegree (p : R[X]) (s : R) : (scaleRoots p s).coeff p.natDegree = p.leadingCoeff := by rw [leadingCoeff, coeff_scaleRoots, tsub_self, pow_zero, mul_one] #align polynomial.coeff_scale_roots_nat_degree Polynomial.coeff_scaleRoots_natDegree @[simp] theorem zero_scaleRoots (s : R) : scaleRoots 0 s = 0 := by ext simp #align polynomial.zero_scale_roots Polynomial.zero_scaleRoots
Mathlib/RingTheory/Polynomial/ScaleRoots.lean
53
59
theorem scaleRoots_ne_zero {p : R[X]} (hp : p ≠ 0) (s : R) : scaleRoots p s ≠ 0 := by intro h
intro h have : p.coeff p.natDegree ≠ 0 := mt leadingCoeff_eq_zero.mp hp have : (scaleRoots p s).coeff p.natDegree = 0 := congr_fun (congr_arg (coeff : R[X] → ℕ → R) h) p.natDegree rw [coeff_scaleRoots_natDegree] at this contradiction
true