Context stringlengths 57 85k | file_name stringlengths 21 79 | start int64 14 2.42k | end int64 18 2.43k | theorem stringlengths 25 2.71k | proof stringlengths 5 10.6k |
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import Mathlib.Analysis.SpecialFunctions.Integrals
#align_import data.real.pi.wallis from "leanprover-community/mathlib"@"980755c33b9168bc82f774f665eaa27878140fac"
open scoped Real Topology Nat
open Filter Finset intervalIntegral
namespace Real
namespace Wallis
set_option linter.uppercaseLean3 false
noncomputable def W (k : ℕ) : ℝ :=
∏ i ∈ range k, (2 * i + 2) / (2 * i + 1) * ((2 * i + 2) / (2 * i + 3))
#align real.wallis.W Real.Wallis.W
theorem W_succ (k : ℕ) :
W (k + 1) = W k * ((2 * k + 2) / (2 * k + 1) * ((2 * k + 2) / (2 * k + 3))) :=
prod_range_succ _ _
#align real.wallis.W_succ Real.Wallis.W_succ
theorem W_pos (k : ℕ) : 0 < W k := by
induction' k with k hk
· unfold W; simp
· rw [W_succ]
refine mul_pos hk (mul_pos (div_pos ?_ ?_) (div_pos ?_ ?_)) <;> positivity
#align real.wallis.W_pos Real.Wallis.W_pos
| Mathlib/Data/Real/Pi/Wallis.lean | 62 | 75 | theorem W_eq_factorial_ratio (n : ℕ) :
W n = 2 ^ (4 * n) * n ! ^ 4 / ((2 * n)! ^ 2 * (2 * n + 1)) := by |
induction' n with n IH
· simp only [W, prod_range_zero, Nat.factorial_zero, mul_zero, pow_zero,
algebraMap.coe_one, one_pow, mul_one, algebraMap.coe_zero, zero_add, div_self, Ne,
one_ne_zero, not_false_iff]
norm_num
· unfold W at IH ⊢
rw [prod_range_succ, IH, _root_.div_mul_div_comm, _root_.div_mul_div_comm]
refine (div_eq_div_iff ?_ ?_).mpr ?_
any_goals exact ne_of_gt (by positivity)
simp_rw [Nat.mul_succ, Nat.factorial_succ, pow_succ]
push_cast
ring_nf
|
import Mathlib.Order.PropInstances
#align_import order.heyting.basic from "leanprover-community/mathlib"@"9ac7c0c8c4d7a535ec3e5b34b8859aab9233b2f4"
open Function OrderDual
universe u
variable {ι α β : Type*}
section
variable (α β)
instance Prod.instHImp [HImp α] [HImp β] : HImp (α × β) :=
⟨fun a b => (a.1 ⇨ b.1, a.2 ⇨ b.2)⟩
instance Prod.instHNot [HNot α] [HNot β] : HNot (α × β) :=
⟨fun a => (￢a.1, ￢a.2)⟩
instance Prod.instSDiff [SDiff α] [SDiff β] : SDiff (α × β) :=
⟨fun a b => (a.1 \ b.1, a.2 \ b.2)⟩
instance Prod.instHasCompl [HasCompl α] [HasCompl β] : HasCompl (α × β) :=
⟨fun a => (a.1ᶜ, a.2ᶜ)⟩
end
@[simp]
theorem fst_himp [HImp α] [HImp β] (a b : α × β) : (a ⇨ b).1 = a.1 ⇨ b.1 :=
rfl
#align fst_himp fst_himp
@[simp]
theorem snd_himp [HImp α] [HImp β] (a b : α × β) : (a ⇨ b).2 = a.2 ⇨ b.2 :=
rfl
#align snd_himp snd_himp
@[simp]
theorem fst_hnot [HNot α] [HNot β] (a : α × β) : (￢a).1 = ￢a.1 :=
rfl
#align fst_hnot fst_hnot
@[simp]
theorem snd_hnot [HNot α] [HNot β] (a : α × β) : (￢a).2 = ￢a.2 :=
rfl
#align snd_hnot snd_hnot
@[simp]
theorem fst_sdiff [SDiff α] [SDiff β] (a b : α × β) : (a \ b).1 = a.1 \ b.1 :=
rfl
#align fst_sdiff fst_sdiff
@[simp]
theorem snd_sdiff [SDiff α] [SDiff β] (a b : α × β) : (a \ b).2 = a.2 \ b.2 :=
rfl
#align snd_sdiff snd_sdiff
@[simp]
theorem fst_compl [HasCompl α] [HasCompl β] (a : α × β) : aᶜ.1 = a.1ᶜ :=
rfl
#align fst_compl fst_compl
@[simp]
theorem snd_compl [HasCompl α] [HasCompl β] (a : α × β) : aᶜ.2 = a.2ᶜ :=
rfl
#align snd_compl snd_compl
class GeneralizedHeytingAlgebra (α : Type*) extends Lattice α, OrderTop α, HImp α where
le_himp_iff (a b c : α) : a ≤ b ⇨ c ↔ a ⊓ b ≤ c
#align generalized_heyting_algebra GeneralizedHeytingAlgebra
#align generalized_heyting_algebra.to_order_top GeneralizedHeytingAlgebra.toOrderTop
class GeneralizedCoheytingAlgebra (α : Type*) extends Lattice α, OrderBot α, SDiff α where
sdiff_le_iff (a b c : α) : a \ b ≤ c ↔ a ≤ b ⊔ c
#align generalized_coheyting_algebra GeneralizedCoheytingAlgebra
#align generalized_coheyting_algebra.to_order_bot GeneralizedCoheytingAlgebra.toOrderBot
class HeytingAlgebra (α : Type*) extends GeneralizedHeytingAlgebra α, OrderBot α, HasCompl α where
himp_bot (a : α) : a ⇨ ⊥ = aᶜ
#align heyting_algebra HeytingAlgebra
class CoheytingAlgebra (α : Type*) extends GeneralizedCoheytingAlgebra α, OrderTop α, HNot α where
top_sdiff (a : α) : ⊤ \ a = ￢a
#align coheyting_algebra CoheytingAlgebra
class BiheytingAlgebra (α : Type*) extends HeytingAlgebra α, SDiff α, HNot α where
sdiff_le_iff (a b c : α) : a \ b ≤ c ↔ a ≤ b ⊔ c
top_sdiff (a : α) : ⊤ \ a = ￢a
#align biheyting_algebra BiheytingAlgebra
-- See note [lower instance priority]
attribute [instance 100] GeneralizedHeytingAlgebra.toOrderTop
attribute [instance 100] GeneralizedCoheytingAlgebra.toOrderBot
-- See note [lower instance priority]
instance (priority := 100) HeytingAlgebra.toBoundedOrder [HeytingAlgebra α] : BoundedOrder α :=
{ bot_le := ‹HeytingAlgebra α›.bot_le }
--#align heyting_algebra.to_bounded_order HeytingAlgebra.toBoundedOrder
-- See note [lower instance priority]
instance (priority := 100) CoheytingAlgebra.toBoundedOrder [CoheytingAlgebra α] : BoundedOrder α :=
{ ‹CoheytingAlgebra α› with }
#align coheyting_algebra.to_bounded_order CoheytingAlgebra.toBoundedOrder
-- See note [lower instance priority]
instance (priority := 100) BiheytingAlgebra.toCoheytingAlgebra [BiheytingAlgebra α] :
CoheytingAlgebra α :=
{ ‹BiheytingAlgebra α› with }
#align biheyting_algebra.to_coheyting_algebra BiheytingAlgebra.toCoheytingAlgebra
-- See note [reducible non-instances]
abbrev HeytingAlgebra.ofHImp [DistribLattice α] [BoundedOrder α] (himp : α → α → α)
(le_himp_iff : ∀ a b c, a ≤ himp b c ↔ a ⊓ b ≤ c) : HeytingAlgebra α :=
{ ‹DistribLattice α›, ‹BoundedOrder α› with
himp,
compl := fun a => himp a ⊥,
le_himp_iff,
himp_bot := fun a => rfl }
#align heyting_algebra.of_himp HeytingAlgebra.ofHImp
-- See note [reducible non-instances]
abbrev HeytingAlgebra.ofCompl [DistribLattice α] [BoundedOrder α] (compl : α → α)
(le_himp_iff : ∀ a b c, a ≤ compl b ⊔ c ↔ a ⊓ b ≤ c) : HeytingAlgebra α where
himp := (compl · ⊔ ·)
compl := compl
le_himp_iff := le_himp_iff
himp_bot _ := sup_bot_eq _
#align heyting_algebra.of_compl HeytingAlgebra.ofCompl
-- See note [reducible non-instances]
abbrev CoheytingAlgebra.ofSDiff [DistribLattice α] [BoundedOrder α] (sdiff : α → α → α)
(sdiff_le_iff : ∀ a b c, sdiff a b ≤ c ↔ a ≤ b ⊔ c) : CoheytingAlgebra α :=
{ ‹DistribLattice α›, ‹BoundedOrder α› with
sdiff,
hnot := fun a => sdiff ⊤ a,
sdiff_le_iff,
top_sdiff := fun a => rfl }
#align coheyting_algebra.of_sdiff CoheytingAlgebra.ofSDiff
-- See note [reducible non-instances]
abbrev CoheytingAlgebra.ofHNot [DistribLattice α] [BoundedOrder α] (hnot : α → α)
(sdiff_le_iff : ∀ a b c, a ⊓ hnot b ≤ c ↔ a ≤ b ⊔ c) : CoheytingAlgebra α where
sdiff a b := a ⊓ hnot b
hnot := hnot
sdiff_le_iff := sdiff_le_iff
top_sdiff _ := top_inf_eq _
#align coheyting_algebra.of_hnot CoheytingAlgebra.ofHNot
section GeneralizedCoheytingAlgebra
variable [GeneralizedCoheytingAlgebra α] {a b c d : α}
@[simp]
theorem sdiff_le_iff : a \ b ≤ c ↔ a ≤ b ⊔ c :=
GeneralizedCoheytingAlgebra.sdiff_le_iff _ _ _
#align sdiff_le_iff sdiff_le_iff
| Mathlib/Order/Heyting/Basic.lean | 444 | 444 | theorem sdiff_le_iff' : a \ b ≤ c ↔ a ≤ c ⊔ b := by | rw [sdiff_le_iff, sup_comm]
|
import Mathlib.Data.ENNReal.Inv
#align_import data.real.ennreal from "leanprover-community/mathlib"@"c14c8fcde993801fca8946b0d80131a1a81d1520"
open Set NNReal ENNReal
namespace ENNReal
section iInf
variable {ι : Sort*} {f g : ι → ℝ≥0∞}
variable {a b c d : ℝ≥0∞} {r p q : ℝ≥0}
theorem toNNReal_iInf (hf : ∀ i, f i ≠ ∞) : (iInf f).toNNReal = ⨅ i, (f i).toNNReal := by
cases isEmpty_or_nonempty ι
· rw [iInf_of_empty, top_toNNReal, NNReal.iInf_empty]
· lift f to ι → ℝ≥0 using hf
simp_rw [← coe_iInf, toNNReal_coe]
#align ennreal.to_nnreal_infi ENNReal.toNNReal_iInf
| Mathlib/Data/ENNReal/Real.lean | 548 | 553 | theorem toNNReal_sInf (s : Set ℝ≥0∞) (hs : ∀ r ∈ s, r ≠ ∞) :
(sInf s).toNNReal = sInf (ENNReal.toNNReal '' s) := by |
have hf : ∀ i, ((↑) : s → ℝ≥0∞) i ≠ ∞ := fun ⟨r, rs⟩ => hs r rs
-- Porting note: `← sInf_image'` had to be replaced by `← image_eq_range` as the lemmas are used
-- in a different order.
simpa only [← sInf_range, ← image_eq_range, Subtype.range_coe_subtype] using (toNNReal_iInf hf)
|
import Mathlib.Topology.Order.IsLUB
open Set Filter TopologicalSpace Topology Function
open OrderDual (toDual ofDual)
variable {α β γ : Type*}
section DenselyOrdered
variable [TopologicalSpace α] [LinearOrder α] [OrderTopology α] [DenselyOrdered α] {a b : α}
{s : Set α}
theorem closure_Ioi' {a : α} (h : (Ioi a).Nonempty) : closure (Ioi a) = Ici a := by
apply Subset.antisymm
· exact closure_minimal Ioi_subset_Ici_self isClosed_Ici
· rw [← diff_subset_closure_iff, Ici_diff_Ioi_same, singleton_subset_iff]
exact isGLB_Ioi.mem_closure h
#align closure_Ioi' closure_Ioi'
@[simp]
theorem closure_Ioi (a : α) [NoMaxOrder α] : closure (Ioi a) = Ici a :=
closure_Ioi' nonempty_Ioi
#align closure_Ioi closure_Ioi
theorem closure_Iio' (h : (Iio a).Nonempty) : closure (Iio a) = Iic a :=
closure_Ioi' (α := αᵒᵈ) h
#align closure_Iio' closure_Iio'
@[simp]
theorem closure_Iio (a : α) [NoMinOrder α] : closure (Iio a) = Iic a :=
closure_Iio' nonempty_Iio
#align closure_Iio closure_Iio
@[simp]
theorem closure_Ioo {a b : α} (hab : a ≠ b) : closure (Ioo a b) = Icc a b := by
apply Subset.antisymm
· exact closure_minimal Ioo_subset_Icc_self isClosed_Icc
· cases' hab.lt_or_lt with hab hab
· rw [← diff_subset_closure_iff, Icc_diff_Ioo_same hab.le]
have hab' : (Ioo a b).Nonempty := nonempty_Ioo.2 hab
simp only [insert_subset_iff, singleton_subset_iff]
exact ⟨(isGLB_Ioo hab).mem_closure hab', (isLUB_Ioo hab).mem_closure hab'⟩
· rw [Icc_eq_empty_of_lt hab]
exact empty_subset _
#align closure_Ioo closure_Ioo
@[simp]
theorem closure_Ioc {a b : α} (hab : a ≠ b) : closure (Ioc a b) = Icc a b := by
apply Subset.antisymm
· exact closure_minimal Ioc_subset_Icc_self isClosed_Icc
· apply Subset.trans _ (closure_mono Ioo_subset_Ioc_self)
rw [closure_Ioo hab]
#align closure_Ioc closure_Ioc
@[simp]
| Mathlib/Topology/Order/DenselyOrdered.lean | 75 | 79 | theorem closure_Ico {a b : α} (hab : a ≠ b) : closure (Ico a b) = Icc a b := by |
apply Subset.antisymm
· exact closure_minimal Ico_subset_Icc_self isClosed_Icc
· apply Subset.trans _ (closure_mono Ioo_subset_Ico_self)
rw [closure_Ioo hab]
|
import Mathlib.Tactic.NormNum
import Mathlib.Tactic.TryThis
import Mathlib.Util.AtomM
set_option autoImplicit true
namespace Mathlib.Tactic.Abel
open Lean Elab Meta Tactic Qq
initialize registerTraceClass `abel
initialize registerTraceClass `abel.detail
structure Context where
α : Expr
univ : Level
α0 : Expr
isGroup : Bool
inst : Expr
def mkContext (e : Expr) : MetaM Context := do
let α ← inferType e
let c ← synthInstance (← mkAppM ``AddCommMonoid #[α])
let cg ← synthInstance? (← mkAppM ``AddCommGroup #[α])
let u ← mkFreshLevelMVar
_ ← isDefEq (.sort (.succ u)) (← inferType α)
let α0 ← Expr.ofNat α 0
match cg with
| some cg => return ⟨α, u, α0, true, cg⟩
| _ => return ⟨α, u, α0, false, c⟩
abbrev M := ReaderT Context AtomM
def Context.app (c : Context) (n : Name) (inst : Expr) : Array Expr → Expr :=
mkAppN (((@Expr.const n [c.univ]).app c.α).app inst)
def Context.mkApp (c : Context) (n inst : Name) (l : Array Expr) : MetaM Expr := do
return c.app n (← synthInstance ((Expr.const inst [c.univ]).app c.α)) l
def addG : Name → Name
| .str p s => .str p (s ++ "g")
| n => n
def iapp (n : Name) (xs : Array Expr) : M Expr := do
let c ← read
return c.app (if c.isGroup then addG n else n) c.inst xs
def term {α} [AddCommMonoid α] (n : ℕ) (x a : α) : α := n • x + a
def termg {α} [AddCommGroup α] (n : ℤ) (x a : α) : α := n • x + a
def mkTerm (n x a : Expr) : M Expr := iapp ``term #[n, x, a]
def intToExpr (n : ℤ) : M Expr := do
Expr.ofInt (mkConst (if (← read).isGroup then ``Int else ``Nat) []) n
inductive NormalExpr : Type
| zero (e : Expr) : NormalExpr
| nterm (e : Expr) (n : Expr × ℤ) (x : ℕ × Expr) (a : NormalExpr) : NormalExpr
deriving Inhabited
def NormalExpr.e : NormalExpr → Expr
| .zero e => e
| .nterm e .. => e
instance : Coe NormalExpr Expr where coe := NormalExpr.e
def NormalExpr.term' (n : Expr × ℤ) (x : ℕ × Expr) (a : NormalExpr) : M NormalExpr :=
return .nterm (← mkTerm n.1 x.2 a) n x a
def NormalExpr.zero' : M NormalExpr := return NormalExpr.zero (← read).α0
open NormalExpr
theorem const_add_term {α} [AddCommMonoid α] (k n x a a') (h : k + a = a') :
k + @term α _ n x a = term n x a' := by
simp [h.symm, term, add_comm, add_assoc]
| Mathlib/Tactic/Abel.lean | 132 | 134 | theorem const_add_termg {α} [AddCommGroup α] (k n x a a') (h : k + a = a') :
k + @termg α _ n x a = termg n x a' := by |
simp [h.symm, termg, add_comm, add_assoc]
|
import Mathlib.Analysis.SpecialFunctions.Trigonometric.Angle
import Mathlib.Analysis.SpecialFunctions.Trigonometric.Inverse
#align_import analysis.special_functions.complex.arg from "leanprover-community/mathlib"@"2c1d8ca2812b64f88992a5294ea3dba144755cd1"
open Filter Metric Set
open scoped ComplexConjugate Real Topology
namespace Complex
variable {a x z : ℂ}
noncomputable def arg (x : ℂ) : ℝ :=
if 0 ≤ x.re then Real.arcsin (x.im / abs x)
else if 0 ≤ x.im then Real.arcsin ((-x).im / abs x) + π else Real.arcsin ((-x).im / abs x) - π
#align complex.arg Complex.arg
theorem sin_arg (x : ℂ) : Real.sin (arg x) = x.im / abs x := by
unfold arg; split_ifs <;>
simp [sub_eq_add_neg, arg,
Real.sin_arcsin (abs_le.1 (abs_im_div_abs_le_one x)).1 (abs_le.1 (abs_im_div_abs_le_one x)).2,
Real.sin_add, neg_div, Real.arcsin_neg, Real.sin_neg]
#align complex.sin_arg Complex.sin_arg
theorem cos_arg {x : ℂ} (hx : x ≠ 0) : Real.cos (arg x) = x.re / abs x := by
rw [arg]
split_ifs with h₁ h₂
· rw [Real.cos_arcsin]
field_simp [Real.sqrt_sq, (abs.pos hx).le, *]
· rw [Real.cos_add_pi, Real.cos_arcsin]
field_simp [Real.sqrt_div (sq_nonneg _), Real.sqrt_sq_eq_abs,
_root_.abs_of_neg (not_le.1 h₁), *]
· rw [Real.cos_sub_pi, Real.cos_arcsin]
field_simp [Real.sqrt_div (sq_nonneg _), Real.sqrt_sq_eq_abs,
_root_.abs_of_neg (not_le.1 h₁), *]
#align complex.cos_arg Complex.cos_arg
@[simp]
theorem abs_mul_exp_arg_mul_I (x : ℂ) : ↑(abs x) * exp (arg x * I) = x := by
rcases eq_or_ne x 0 with (rfl | hx)
· simp
· have : abs x ≠ 0 := abs.ne_zero hx
apply Complex.ext <;> field_simp [sin_arg, cos_arg hx, this, mul_comm (abs x)]
set_option linter.uppercaseLean3 false in
#align complex.abs_mul_exp_arg_mul_I Complex.abs_mul_exp_arg_mul_I
@[simp]
theorem abs_mul_cos_add_sin_mul_I (x : ℂ) : (abs x * (cos (arg x) + sin (arg x) * I) : ℂ) = x := by
rw [← exp_mul_I, abs_mul_exp_arg_mul_I]
set_option linter.uppercaseLean3 false in
#align complex.abs_mul_cos_add_sin_mul_I Complex.abs_mul_cos_add_sin_mul_I
@[simp]
lemma abs_mul_cos_arg (x : ℂ) : abs x * Real.cos (arg x) = x.re := by
simpa [-abs_mul_cos_add_sin_mul_I] using congr_arg re (abs_mul_cos_add_sin_mul_I x)
@[simp]
lemma abs_mul_sin_arg (x : ℂ) : abs x * Real.sin (arg x) = x.im := by
simpa [-abs_mul_cos_add_sin_mul_I] using congr_arg im (abs_mul_cos_add_sin_mul_I x)
theorem abs_eq_one_iff (z : ℂ) : abs z = 1 ↔ ∃ θ : ℝ, exp (θ * I) = z := by
refine ⟨fun hz => ⟨arg z, ?_⟩, ?_⟩
· calc
exp (arg z * I) = abs z * exp (arg z * I) := by rw [hz, ofReal_one, one_mul]
_ = z := abs_mul_exp_arg_mul_I z
· rintro ⟨θ, rfl⟩
exact Complex.abs_exp_ofReal_mul_I θ
#align complex.abs_eq_one_iff Complex.abs_eq_one_iff
@[simp]
theorem range_exp_mul_I : (Set.range fun x : ℝ => exp (x * I)) = Metric.sphere 0 1 := by
ext x
simp only [mem_sphere_zero_iff_norm, norm_eq_abs, abs_eq_one_iff, Set.mem_range]
set_option linter.uppercaseLean3 false in
#align complex.range_exp_mul_I Complex.range_exp_mul_I
theorem arg_mul_cos_add_sin_mul_I {r : ℝ} (hr : 0 < r) {θ : ℝ} (hθ : θ ∈ Set.Ioc (-π) π) :
arg (r * (cos θ + sin θ * I)) = θ := by
simp only [arg, map_mul, abs_cos_add_sin_mul_I, abs_of_nonneg hr.le, mul_one]
simp only [re_ofReal_mul, im_ofReal_mul, neg_im, ← ofReal_cos, ← ofReal_sin, ←
mk_eq_add_mul_I, neg_div, mul_div_cancel_left₀ _ hr.ne', mul_nonneg_iff_right_nonneg_of_pos hr]
by_cases h₁ : θ ∈ Set.Icc (-(π / 2)) (π / 2)
· rw [if_pos]
exacts [Real.arcsin_sin' h₁, Real.cos_nonneg_of_mem_Icc h₁]
· rw [Set.mem_Icc, not_and_or, not_le, not_le] at h₁
cases' h₁ with h₁ h₁
· replace hθ := hθ.1
have hcos : Real.cos θ < 0 := by
rw [← neg_pos, ← Real.cos_add_pi]
refine Real.cos_pos_of_mem_Ioo ⟨?_, ?_⟩ <;> linarith
have hsin : Real.sin θ < 0 := Real.sin_neg_of_neg_of_neg_pi_lt (by linarith) hθ
rw [if_neg, if_neg, ← Real.sin_add_pi, Real.arcsin_sin, add_sub_cancel_right] <;> [linarith;
linarith; exact hsin.not_le; exact hcos.not_le]
· replace hθ := hθ.2
have hcos : Real.cos θ < 0 := Real.cos_neg_of_pi_div_two_lt_of_lt h₁ (by linarith)
have hsin : 0 ≤ Real.sin θ := Real.sin_nonneg_of_mem_Icc ⟨by linarith, hθ⟩
rw [if_neg, if_pos, ← Real.sin_sub_pi, Real.arcsin_sin, sub_add_cancel] <;> [linarith;
linarith; exact hsin; exact hcos.not_le]
set_option linter.uppercaseLean3 false in
#align complex.arg_mul_cos_add_sin_mul_I Complex.arg_mul_cos_add_sin_mul_I
theorem arg_cos_add_sin_mul_I {θ : ℝ} (hθ : θ ∈ Set.Ioc (-π) π) : arg (cos θ + sin θ * I) = θ := by
rw [← one_mul (_ + _), ← ofReal_one, arg_mul_cos_add_sin_mul_I zero_lt_one hθ]
set_option linter.uppercaseLean3 false in
#align complex.arg_cos_add_sin_mul_I Complex.arg_cos_add_sin_mul_I
lemma arg_exp_mul_I (θ : ℝ) :
arg (exp (θ * I)) = toIocMod (mul_pos two_pos Real.pi_pos) (-π) θ := by
convert arg_cos_add_sin_mul_I (θ := toIocMod (mul_pos two_pos Real.pi_pos) (-π) θ) _ using 2
· rw [← exp_mul_I, eq_sub_of_add_eq $ toIocMod_add_toIocDiv_zsmul _ _ θ, ofReal_sub,
ofReal_zsmul, ofReal_mul, ofReal_ofNat, exp_mul_I_periodic.sub_zsmul_eq]
· convert toIocMod_mem_Ioc _ _ _
ring
@[simp]
theorem arg_zero : arg 0 = 0 := by simp [arg, le_refl]
#align complex.arg_zero Complex.arg_zero
theorem ext_abs_arg {x y : ℂ} (h₁ : abs x = abs y) (h₂ : x.arg = y.arg) : x = y := by
rw [← abs_mul_exp_arg_mul_I x, ← abs_mul_exp_arg_mul_I y, h₁, h₂]
#align complex.ext_abs_arg Complex.ext_abs_arg
theorem ext_abs_arg_iff {x y : ℂ} : x = y ↔ abs x = abs y ∧ arg x = arg y :=
⟨fun h => h ▸ ⟨rfl, rfl⟩, and_imp.2 ext_abs_arg⟩
#align complex.ext_abs_arg_iff Complex.ext_abs_arg_iff
theorem arg_mem_Ioc (z : ℂ) : arg z ∈ Set.Ioc (-π) π := by
have hπ : 0 < π := Real.pi_pos
rcases eq_or_ne z 0 with (rfl | hz)
· simp [hπ, hπ.le]
rcases existsUnique_add_zsmul_mem_Ioc Real.two_pi_pos (arg z) (-π) with ⟨N, hN, -⟩
rw [two_mul, neg_add_cancel_left, ← two_mul, zsmul_eq_mul] at hN
rw [← abs_mul_cos_add_sin_mul_I z, ← cos_add_int_mul_two_pi _ N, ← sin_add_int_mul_two_pi _ N]
have := arg_mul_cos_add_sin_mul_I (abs.pos hz) hN
push_cast at this
rwa [this]
#align complex.arg_mem_Ioc Complex.arg_mem_Ioc
@[simp]
theorem range_arg : Set.range arg = Set.Ioc (-π) π :=
(Set.range_subset_iff.2 arg_mem_Ioc).antisymm fun _ hx => ⟨_, arg_cos_add_sin_mul_I hx⟩
#align complex.range_arg Complex.range_arg
theorem arg_le_pi (x : ℂ) : arg x ≤ π :=
(arg_mem_Ioc x).2
#align complex.arg_le_pi Complex.arg_le_pi
theorem neg_pi_lt_arg (x : ℂ) : -π < arg x :=
(arg_mem_Ioc x).1
#align complex.neg_pi_lt_arg Complex.neg_pi_lt_arg
theorem abs_arg_le_pi (z : ℂ) : |arg z| ≤ π :=
abs_le.2 ⟨(neg_pi_lt_arg z).le, arg_le_pi z⟩
#align complex.abs_arg_le_pi Complex.abs_arg_le_pi
@[simp]
theorem arg_nonneg_iff {z : ℂ} : 0 ≤ arg z ↔ 0 ≤ z.im := by
rcases eq_or_ne z 0 with (rfl | h₀); · simp
calc
0 ≤ arg z ↔ 0 ≤ Real.sin (arg z) :=
⟨fun h => Real.sin_nonneg_of_mem_Icc ⟨h, arg_le_pi z⟩, by
contrapose!
intro h
exact Real.sin_neg_of_neg_of_neg_pi_lt h (neg_pi_lt_arg _)⟩
_ ↔ _ := by rw [sin_arg, le_div_iff (abs.pos h₀), zero_mul]
#align complex.arg_nonneg_iff Complex.arg_nonneg_iff
@[simp]
theorem arg_neg_iff {z : ℂ} : arg z < 0 ↔ z.im < 0 :=
lt_iff_lt_of_le_iff_le arg_nonneg_iff
#align complex.arg_neg_iff Complex.arg_neg_iff
theorem arg_real_mul (x : ℂ) {r : ℝ} (hr : 0 < r) : arg (r * x) = arg x := by
rcases eq_or_ne x 0 with (rfl | hx); · rw [mul_zero]
conv_lhs =>
rw [← abs_mul_cos_add_sin_mul_I x, ← mul_assoc, ← ofReal_mul,
arg_mul_cos_add_sin_mul_I (mul_pos hr (abs.pos hx)) x.arg_mem_Ioc]
#align complex.arg_real_mul Complex.arg_real_mul
theorem arg_mul_real {r : ℝ} (hr : 0 < r) (x : ℂ) : arg (x * r) = arg x :=
mul_comm x r ▸ arg_real_mul x hr
theorem arg_eq_arg_iff {x y : ℂ} (hx : x ≠ 0) (hy : y ≠ 0) :
arg x = arg y ↔ (abs y / abs x : ℂ) * x = y := by
simp only [ext_abs_arg_iff, map_mul, map_div₀, abs_ofReal, abs_abs,
div_mul_cancel₀ _ (abs.ne_zero hx), eq_self_iff_true, true_and_iff]
rw [← ofReal_div, arg_real_mul]
exact div_pos (abs.pos hy) (abs.pos hx)
#align complex.arg_eq_arg_iff Complex.arg_eq_arg_iff
@[simp]
theorem arg_one : arg 1 = 0 := by simp [arg, zero_le_one]
#align complex.arg_one Complex.arg_one
@[simp]
theorem arg_neg_one : arg (-1) = π := by simp [arg, le_refl, not_le.2 (zero_lt_one' ℝ)]
#align complex.arg_neg_one Complex.arg_neg_one
@[simp]
theorem arg_I : arg I = π / 2 := by simp [arg, le_refl]
set_option linter.uppercaseLean3 false in
#align complex.arg_I Complex.arg_I
@[simp]
theorem arg_neg_I : arg (-I) = -(π / 2) := by simp [arg, le_refl]
set_option linter.uppercaseLean3 false in
#align complex.arg_neg_I Complex.arg_neg_I
@[simp]
theorem tan_arg (x : ℂ) : Real.tan (arg x) = x.im / x.re := by
by_cases h : x = 0
· simp only [h, zero_div, Complex.zero_im, Complex.arg_zero, Real.tan_zero, Complex.zero_re]
rw [Real.tan_eq_sin_div_cos, sin_arg, cos_arg h, div_div_div_cancel_right _ (abs.ne_zero h)]
#align complex.tan_arg Complex.tan_arg
theorem arg_ofReal_of_nonneg {x : ℝ} (hx : 0 ≤ x) : arg x = 0 := by simp [arg, hx]
#align complex.arg_of_real_of_nonneg Complex.arg_ofReal_of_nonneg
@[simp, norm_cast]
lemma natCast_arg {n : ℕ} : arg n = 0 :=
ofReal_natCast n ▸ arg_ofReal_of_nonneg n.cast_nonneg
@[simp]
lemma ofNat_arg {n : ℕ} [n.AtLeastTwo] : arg (no_index (OfNat.ofNat n)) = 0 :=
natCast_arg
theorem arg_eq_zero_iff {z : ℂ} : arg z = 0 ↔ 0 ≤ z.re ∧ z.im = 0 := by
refine ⟨fun h => ?_, ?_⟩
· rw [← abs_mul_cos_add_sin_mul_I z, h]
simp [abs.nonneg]
· cases' z with x y
rintro ⟨h, rfl : y = 0⟩
exact arg_ofReal_of_nonneg h
#align complex.arg_eq_zero_iff Complex.arg_eq_zero_iff
open ComplexOrder in
lemma arg_eq_zero_iff_zero_le {z : ℂ} : arg z = 0 ↔ 0 ≤ z := by
rw [arg_eq_zero_iff, eq_comm, nonneg_iff]
theorem arg_eq_pi_iff {z : ℂ} : arg z = π ↔ z.re < 0 ∧ z.im = 0 := by
by_cases h₀ : z = 0
· simp [h₀, lt_irrefl, Real.pi_ne_zero.symm]
constructor
· intro h
rw [← abs_mul_cos_add_sin_mul_I z, h]
simp [h₀]
· cases' z with x y
rintro ⟨h : x < 0, rfl : y = 0⟩
rw [← arg_neg_one, ← arg_real_mul (-1) (neg_pos.2 h)]
simp [← ofReal_def]
#align complex.arg_eq_pi_iff Complex.arg_eq_pi_iff
open ComplexOrder in
lemma arg_eq_pi_iff_lt_zero {z : ℂ} : arg z = π ↔ z < 0 := arg_eq_pi_iff
theorem arg_lt_pi_iff {z : ℂ} : arg z < π ↔ 0 ≤ z.re ∨ z.im ≠ 0 := by
rw [(arg_le_pi z).lt_iff_ne, not_iff_comm, not_or, not_le, Classical.not_not, arg_eq_pi_iff]
#align complex.arg_lt_pi_iff Complex.arg_lt_pi_iff
theorem arg_ofReal_of_neg {x : ℝ} (hx : x < 0) : arg x = π :=
arg_eq_pi_iff.2 ⟨hx, rfl⟩
#align complex.arg_of_real_of_neg Complex.arg_ofReal_of_neg
theorem arg_eq_pi_div_two_iff {z : ℂ} : arg z = π / 2 ↔ z.re = 0 ∧ 0 < z.im := by
by_cases h₀ : z = 0; · simp [h₀, lt_irrefl, Real.pi_div_two_pos.ne]
constructor
· intro h
rw [← abs_mul_cos_add_sin_mul_I z, h]
simp [h₀]
· cases' z with x y
rintro ⟨rfl : x = 0, hy : 0 < y⟩
rw [← arg_I, ← arg_real_mul I hy, ofReal_mul', I_re, I_im, mul_zero, mul_one]
#align complex.arg_eq_pi_div_two_iff Complex.arg_eq_pi_div_two_iff
theorem arg_eq_neg_pi_div_two_iff {z : ℂ} : arg z = -(π / 2) ↔ z.re = 0 ∧ z.im < 0 := by
by_cases h₀ : z = 0; · simp [h₀, lt_irrefl, Real.pi_ne_zero]
constructor
· intro h
rw [← abs_mul_cos_add_sin_mul_I z, h]
simp [h₀]
· cases' z with x y
rintro ⟨rfl : x = 0, hy : y < 0⟩
rw [← arg_neg_I, ← arg_real_mul (-I) (neg_pos.2 hy), mk_eq_add_mul_I]
simp
#align complex.arg_eq_neg_pi_div_two_iff Complex.arg_eq_neg_pi_div_two_iff
theorem arg_of_re_nonneg {x : ℂ} (hx : 0 ≤ x.re) : arg x = Real.arcsin (x.im / abs x) :=
if_pos hx
#align complex.arg_of_re_nonneg Complex.arg_of_re_nonneg
theorem arg_of_re_neg_of_im_nonneg {x : ℂ} (hx_re : x.re < 0) (hx_im : 0 ≤ x.im) :
arg x = Real.arcsin ((-x).im / abs x) + π := by
simp only [arg, hx_re.not_le, hx_im, if_true, if_false]
#align complex.arg_of_re_neg_of_im_nonneg Complex.arg_of_re_neg_of_im_nonneg
theorem arg_of_re_neg_of_im_neg {x : ℂ} (hx_re : x.re < 0) (hx_im : x.im < 0) :
arg x = Real.arcsin ((-x).im / abs x) - π := by
simp only [arg, hx_re.not_le, hx_im.not_le, if_false]
#align complex.arg_of_re_neg_of_im_neg Complex.arg_of_re_neg_of_im_neg
theorem arg_of_im_nonneg_of_ne_zero {z : ℂ} (h₁ : 0 ≤ z.im) (h₂ : z ≠ 0) :
arg z = Real.arccos (z.re / abs z) := by
rw [← cos_arg h₂, Real.arccos_cos (arg_nonneg_iff.2 h₁) (arg_le_pi _)]
#align complex.arg_of_im_nonneg_of_ne_zero Complex.arg_of_im_nonneg_of_ne_zero
theorem arg_of_im_pos {z : ℂ} (hz : 0 < z.im) : arg z = Real.arccos (z.re / abs z) :=
arg_of_im_nonneg_of_ne_zero hz.le fun h => hz.ne' <| h.symm ▸ rfl
#align complex.arg_of_im_pos Complex.arg_of_im_pos
theorem arg_of_im_neg {z : ℂ} (hz : z.im < 0) : arg z = -Real.arccos (z.re / abs z) := by
have h₀ : z ≠ 0 := mt (congr_arg im) hz.ne
rw [← cos_arg h₀, ← Real.cos_neg, Real.arccos_cos, neg_neg]
exacts [neg_nonneg.2 (arg_neg_iff.2 hz).le, neg_le.2 (neg_pi_lt_arg z).le]
#align complex.arg_of_im_neg Complex.arg_of_im_neg
theorem arg_conj (x : ℂ) : arg (conj x) = if arg x = π then π else -arg x := by
simp_rw [arg_eq_pi_iff, arg, neg_im, conj_im, conj_re, abs_conj, neg_div, neg_neg,
Real.arcsin_neg]
rcases lt_trichotomy x.re 0 with (hr | hr | hr) <;>
rcases lt_trichotomy x.im 0 with (hi | hi | hi)
· simp [hr, hr.not_le, hi.le, hi.ne, not_le.2 hi, add_comm]
· simp [hr, hr.not_le, hi]
· simp [hr, hr.not_le, hi.ne.symm, hi.le, not_le.2 hi, sub_eq_neg_add]
· simp [hr]
· simp [hr]
· simp [hr]
· simp [hr, hr.le, hi.ne]
· simp [hr, hr.le, hr.le.not_lt]
· simp [hr, hr.le, hr.le.not_lt]
#align complex.arg_conj Complex.arg_conj
theorem arg_inv (x : ℂ) : arg x⁻¹ = if arg x = π then π else -arg x := by
rw [← arg_conj, inv_def, mul_comm]
by_cases hx : x = 0
· simp [hx]
· exact arg_real_mul (conj x) (by simp [hx])
#align complex.arg_inv Complex.arg_inv
@[simp] lemma abs_arg_inv (x : ℂ) : |x⁻¹.arg| = |x.arg| := by rw [arg_inv]; split_ifs <;> simp [*]
-- TODO: Replace the next two lemmas by general facts about periodic functions
lemma abs_eq_one_iff' : abs x = 1 ↔ ∃ θ ∈ Set.Ioc (-π) π, exp (θ * I) = x := by
rw [abs_eq_one_iff]
constructor
· rintro ⟨θ, rfl⟩
refine ⟨toIocMod (mul_pos two_pos Real.pi_pos) (-π) θ, ?_, ?_⟩
· convert toIocMod_mem_Ioc _ _ _
ring
· rw [eq_sub_of_add_eq $ toIocMod_add_toIocDiv_zsmul _ _ θ, ofReal_sub,
ofReal_zsmul, ofReal_mul, ofReal_ofNat, exp_mul_I_periodic.sub_zsmul_eq]
· rintro ⟨θ, _, rfl⟩
exact ⟨θ, rfl⟩
lemma image_exp_Ioc_eq_sphere : (fun θ : ℝ ↦ exp (θ * I)) '' Set.Ioc (-π) π = sphere 0 1 := by
ext; simpa using abs_eq_one_iff'.symm
theorem arg_le_pi_div_two_iff {z : ℂ} : arg z ≤ π / 2 ↔ 0 ≤ re z ∨ im z < 0 := by
rcases le_or_lt 0 (re z) with hre | hre
· simp only [hre, arg_of_re_nonneg hre, Real.arcsin_le_pi_div_two, true_or_iff]
simp only [hre.not_le, false_or_iff]
rcases le_or_lt 0 (im z) with him | him
· simp only [him.not_lt]
rw [iff_false_iff, not_le, arg_of_re_neg_of_im_nonneg hre him, ← sub_lt_iff_lt_add, half_sub,
Real.neg_pi_div_two_lt_arcsin, neg_im, neg_div, neg_lt_neg_iff, div_lt_one, ←
_root_.abs_of_nonneg him, abs_im_lt_abs]
exacts [hre.ne, abs.pos <| ne_of_apply_ne re hre.ne]
· simp only [him]
rw [iff_true_iff, arg_of_re_neg_of_im_neg hre him]
exact (sub_le_self _ Real.pi_pos.le).trans (Real.arcsin_le_pi_div_two _)
#align complex.arg_le_pi_div_two_iff Complex.arg_le_pi_div_two_iff
theorem neg_pi_div_two_le_arg_iff {z : ℂ} : -(π / 2) ≤ arg z ↔ 0 ≤ re z ∨ 0 ≤ im z := by
rcases le_or_lt 0 (re z) with hre | hre
· simp only [hre, arg_of_re_nonneg hre, Real.neg_pi_div_two_le_arcsin, true_or_iff]
simp only [hre.not_le, false_or_iff]
rcases le_or_lt 0 (im z) with him | him
· simp only [him]
rw [iff_true_iff, arg_of_re_neg_of_im_nonneg hre him]
exact (Real.neg_pi_div_two_le_arcsin _).trans (le_add_of_nonneg_right Real.pi_pos.le)
· simp only [him.not_le]
rw [iff_false_iff, not_le, arg_of_re_neg_of_im_neg hre him, sub_lt_iff_lt_add', ←
sub_eq_add_neg, sub_half, Real.arcsin_lt_pi_div_two, div_lt_one, neg_im, ← abs_of_neg him,
abs_im_lt_abs]
exacts [hre.ne, abs.pos <| ne_of_apply_ne re hre.ne]
#align complex.neg_pi_div_two_le_arg_iff Complex.neg_pi_div_two_le_arg_iff
lemma neg_pi_div_two_lt_arg_iff {z : ℂ} : -(π / 2) < arg z ↔ 0 < re z ∨ 0 ≤ im z := by
rw [lt_iff_le_and_ne, neg_pi_div_two_le_arg_iff, ne_comm, Ne, arg_eq_neg_pi_div_two_iff]
rcases lt_trichotomy z.re 0 with hre | hre | hre
· simp [hre.ne, hre.not_le, hre.not_lt]
· simp [hre]
· simp [hre, hre.le, hre.ne']
lemma arg_lt_pi_div_two_iff {z : ℂ} : arg z < π / 2 ↔ 0 < re z ∨ im z < 0 ∨ z = 0 := by
rw [lt_iff_le_and_ne, arg_le_pi_div_two_iff, Ne, arg_eq_pi_div_two_iff]
rcases lt_trichotomy z.re 0 with hre | hre | hre
· have : z ≠ 0 := by simp [ext_iff, hre.ne]
simp [hre.ne, hre.not_le, hre.not_lt, this]
· have : z = 0 ↔ z.im = 0 := by simp [ext_iff, hre]
simp [hre, this, or_comm, le_iff_eq_or_lt]
· simp [hre, hre.le, hre.ne']
@[simp]
theorem abs_arg_le_pi_div_two_iff {z : ℂ} : |arg z| ≤ π / 2 ↔ 0 ≤ re z := by
rw [abs_le, arg_le_pi_div_two_iff, neg_pi_div_two_le_arg_iff, ← or_and_left, ← not_le,
and_not_self_iff, or_false_iff]
#align complex.abs_arg_le_pi_div_two_iff Complex.abs_arg_le_pi_div_two_iff
@[simp]
theorem abs_arg_lt_pi_div_two_iff {z : ℂ} : |arg z| < π / 2 ↔ 0 < re z ∨ z = 0 := by
rw [abs_lt, arg_lt_pi_div_two_iff, neg_pi_div_two_lt_arg_iff, ← or_and_left]
rcases eq_or_ne z 0 with hz | hz
· simp [hz]
· simp_rw [hz, or_false, ← not_lt, not_and_self_iff, or_false]
@[simp]
theorem arg_conj_coe_angle (x : ℂ) : (arg (conj x) : Real.Angle) = -arg x := by
by_cases h : arg x = π <;> simp [arg_conj, h]
#align complex.arg_conj_coe_angle Complex.arg_conj_coe_angle
@[simp]
theorem arg_inv_coe_angle (x : ℂ) : (arg x⁻¹ : Real.Angle) = -arg x := by
by_cases h : arg x = π <;> simp [arg_inv, h]
#align complex.arg_inv_coe_angle Complex.arg_inv_coe_angle
theorem arg_neg_eq_arg_sub_pi_of_im_pos {x : ℂ} (hi : 0 < x.im) : arg (-x) = arg x - π := by
rw [arg_of_im_pos hi, arg_of_im_neg (show (-x).im < 0 from Left.neg_neg_iff.2 hi)]
simp [neg_div, Real.arccos_neg]
#align complex.arg_neg_eq_arg_sub_pi_of_im_pos Complex.arg_neg_eq_arg_sub_pi_of_im_pos
theorem arg_neg_eq_arg_add_pi_of_im_neg {x : ℂ} (hi : x.im < 0) : arg (-x) = arg x + π := by
rw [arg_of_im_neg hi, arg_of_im_pos (show 0 < (-x).im from Left.neg_pos_iff.2 hi)]
simp [neg_div, Real.arccos_neg, add_comm, ← sub_eq_add_neg]
#align complex.arg_neg_eq_arg_add_pi_of_im_neg Complex.arg_neg_eq_arg_add_pi_of_im_neg
theorem arg_neg_eq_arg_sub_pi_iff {x : ℂ} :
arg (-x) = arg x - π ↔ 0 < x.im ∨ x.im = 0 ∧ x.re < 0 := by
rcases lt_trichotomy x.im 0 with (hi | hi | hi)
· simp [hi, hi.ne, hi.not_lt, arg_neg_eq_arg_add_pi_of_im_neg, sub_eq_add_neg, ←
add_eq_zero_iff_eq_neg, Real.pi_ne_zero]
· rw [(ext rfl hi : x = x.re)]
rcases lt_trichotomy x.re 0 with (hr | hr | hr)
· rw [arg_ofReal_of_neg hr, ← ofReal_neg, arg_ofReal_of_nonneg (Left.neg_pos_iff.2 hr).le]
simp [hr]
· simp [hr, hi, Real.pi_ne_zero]
· rw [arg_ofReal_of_nonneg hr.le, ← ofReal_neg, arg_ofReal_of_neg (Left.neg_neg_iff.2 hr)]
simp [hr.not_lt, ← add_eq_zero_iff_eq_neg, Real.pi_ne_zero]
· simp [hi, arg_neg_eq_arg_sub_pi_of_im_pos]
#align complex.arg_neg_eq_arg_sub_pi_iff Complex.arg_neg_eq_arg_sub_pi_iff
theorem arg_neg_eq_arg_add_pi_iff {x : ℂ} :
arg (-x) = arg x + π ↔ x.im < 0 ∨ x.im = 0 ∧ 0 < x.re := by
rcases lt_trichotomy x.im 0 with (hi | hi | hi)
· simp [hi, arg_neg_eq_arg_add_pi_of_im_neg]
· rw [(ext rfl hi : x = x.re)]
rcases lt_trichotomy x.re 0 with (hr | hr | hr)
· rw [arg_ofReal_of_neg hr, ← ofReal_neg, arg_ofReal_of_nonneg (Left.neg_pos_iff.2 hr).le]
simp [hr.not_lt, ← two_mul, Real.pi_ne_zero]
· simp [hr, hi, Real.pi_ne_zero.symm]
· rw [arg_ofReal_of_nonneg hr.le, ← ofReal_neg, arg_ofReal_of_neg (Left.neg_neg_iff.2 hr)]
simp [hr]
· simp [hi, hi.ne.symm, hi.not_lt, arg_neg_eq_arg_sub_pi_of_im_pos, sub_eq_add_neg, ←
add_eq_zero_iff_neg_eq, Real.pi_ne_zero]
#align complex.arg_neg_eq_arg_add_pi_iff Complex.arg_neg_eq_arg_add_pi_iff
| Mathlib/Analysis/SpecialFunctions/Complex/Arg.lean | 483 | 493 | theorem arg_neg_coe_angle {x : ℂ} (hx : x ≠ 0) : (arg (-x) : Real.Angle) = arg x + π := by |
rcases lt_trichotomy x.im 0 with (hi | hi | hi)
· rw [arg_neg_eq_arg_add_pi_of_im_neg hi, Real.Angle.coe_add]
· rw [(ext rfl hi : x = x.re)]
rcases lt_trichotomy x.re 0 with (hr | hr | hr)
· rw [arg_ofReal_of_neg hr, ← ofReal_neg, arg_ofReal_of_nonneg (Left.neg_pos_iff.2 hr).le, ←
Real.Angle.coe_add, ← two_mul, Real.Angle.coe_two_pi, Real.Angle.coe_zero]
· exact False.elim (hx (ext hr hi))
· rw [arg_ofReal_of_nonneg hr.le, ← ofReal_neg, arg_ofReal_of_neg (Left.neg_neg_iff.2 hr),
Real.Angle.coe_zero, zero_add]
· rw [arg_neg_eq_arg_sub_pi_of_im_pos hi, Real.Angle.coe_sub, Real.Angle.sub_coe_pi_eq_add_coe_pi]
|
import Mathlib.Topology.LocalAtTarget
import Mathlib.AlgebraicGeometry.Morphisms.Basic
#align_import algebraic_geometry.morphisms.open_immersion from "leanprover-community/mathlib"@"f0c8bf9245297a541f468be517f1bde6195105e9"
noncomputable section
open CategoryTheory CategoryTheory.Limits Opposite TopologicalSpace
universe u
namespace AlgebraicGeometry
variable {X Y Z : Scheme.{u}} (f : X ⟶ Y) (g : Y ⟶ Z)
| Mathlib/AlgebraicGeometry/Morphisms/OpenImmersion.lean | 34 | 38 | theorem isOpenImmersion_iff_stalk {f : X ⟶ Y} : IsOpenImmersion f ↔
OpenEmbedding f.1.base ∧ ∀ x, IsIso (PresheafedSpace.stalkMap f.1 x) := by |
constructor
· intro h; exact ⟨h.1, inferInstance⟩
· rintro ⟨h₁, h₂⟩; exact IsOpenImmersion.of_stalk_iso f h₁
|
import Mathlib.Algebra.BigOperators.Fin
import Mathlib.LinearAlgebra.Finsupp
import Mathlib.LinearAlgebra.Prod
import Mathlib.SetTheory.Cardinal.Basic
import Mathlib.Tactic.FinCases
import Mathlib.Tactic.LinearCombination
import Mathlib.Lean.Expr.ExtraRecognizers
import Mathlib.Data.Set.Subsingleton
#align_import linear_algebra.linear_independent from "leanprover-community/mathlib"@"9d684a893c52e1d6692a504a118bfccbae04feeb"
noncomputable section
open Function Set Submodule
open Cardinal
universe u' u
variable {ι : Type u'} {ι' : Type*} {R : Type*} {K : Type*}
variable {M : Type*} {M' M'' : Type*} {V : Type u} {V' : Type*}
section Module
variable {v : ι → M}
variable [Semiring R] [AddCommMonoid M] [AddCommMonoid M'] [AddCommMonoid M'']
variable [Module R M] [Module R M'] [Module R M'']
variable {a b : R} {x y : M}
variable (R) (v)
def LinearIndependent : Prop :=
LinearMap.ker (Finsupp.total ι M R v) = ⊥
#align linear_independent LinearIndependent
open Lean PrettyPrinter.Delaborator SubExpr in
@[delab app.LinearIndependent]
def delabLinearIndependent : Delab :=
whenPPOption getPPNotation <|
whenNotPPOption getPPAnalysisSkip <|
withOptionAtCurrPos `pp.analysis.skip true do
let e ← getExpr
guard <| e.isAppOfArity ``LinearIndependent 7
let some _ := (e.getArg! 0).coeTypeSet? | failure
let optionsPerPos ← if (e.getArg! 3).isLambda then
withNaryArg 3 do return (← read).optionsPerPos.setBool (← getPos) pp.funBinderTypes.name true
else
withNaryArg 0 do return (← read).optionsPerPos.setBool (← getPos) `pp.analysis.namedArg true
withTheReader Context ({· with optionsPerPos}) delab
variable {R} {v}
theorem linearIndependent_iff :
LinearIndependent R v ↔ ∀ l, Finsupp.total ι M R v l = 0 → l = 0 := by
simp [LinearIndependent, LinearMap.ker_eq_bot']
#align linear_independent_iff linearIndependent_iff
theorem linearIndependent_iff' :
LinearIndependent R v ↔
∀ s : Finset ι, ∀ g : ι → R, ∑ i ∈ s, g i • v i = 0 → ∀ i ∈ s, g i = 0 :=
linearIndependent_iff.trans
⟨fun hf s g hg i his =>
have h :=
hf (∑ i ∈ s, Finsupp.single i (g i)) <| by
simpa only [map_sum, Finsupp.total_single] using hg
calc
g i = (Finsupp.lapply i : (ι →₀ R) →ₗ[R] R) (Finsupp.single i (g i)) := by
{ rw [Finsupp.lapply_apply, Finsupp.single_eq_same] }
_ = ∑ j ∈ s, (Finsupp.lapply i : (ι →₀ R) →ₗ[R] R) (Finsupp.single j (g j)) :=
Eq.symm <|
Finset.sum_eq_single i
(fun j _hjs hji => by rw [Finsupp.lapply_apply, Finsupp.single_eq_of_ne hji])
fun hnis => hnis.elim his
_ = (∑ j ∈ s, Finsupp.single j (g j)) i := (map_sum ..).symm
_ = 0 := DFunLike.ext_iff.1 h i,
fun hf l hl =>
Finsupp.ext fun i =>
_root_.by_contradiction fun hni => hni <| hf _ _ hl _ <| Finsupp.mem_support_iff.2 hni⟩
#align linear_independent_iff' linearIndependent_iff'
theorem linearIndependent_iff'' :
LinearIndependent R v ↔
∀ (s : Finset ι) (g : ι → R), (∀ i ∉ s, g i = 0) →
∑ i ∈ s, g i • v i = 0 → ∀ i, g i = 0 := by
classical
exact linearIndependent_iff'.trans
⟨fun H s g hg hv i => if his : i ∈ s then H s g hv i his else hg i his, fun H s g hg i hi => by
convert
H s (fun j => if j ∈ s then g j else 0) (fun j hj => if_neg hj)
(by simp_rw [ite_smul, zero_smul, Finset.sum_extend_by_zero, hg]) i
exact (if_pos hi).symm⟩
#align linear_independent_iff'' linearIndependent_iff''
theorem not_linearIndependent_iff :
¬LinearIndependent R v ↔
∃ s : Finset ι, ∃ g : ι → R, ∑ i ∈ s, g i • v i = 0 ∧ ∃ i ∈ s, g i ≠ 0 := by
rw [linearIndependent_iff']
simp only [exists_prop, not_forall]
#align not_linear_independent_iff not_linearIndependent_iff
theorem Fintype.linearIndependent_iff [Fintype ι] :
LinearIndependent R v ↔ ∀ g : ι → R, ∑ i, g i • v i = 0 → ∀ i, g i = 0 := by
refine
⟨fun H g => by simpa using linearIndependent_iff'.1 H Finset.univ g, fun H =>
linearIndependent_iff''.2 fun s g hg hs i => H _ ?_ _⟩
rw [← hs]
refine (Finset.sum_subset (Finset.subset_univ _) fun i _ hi => ?_).symm
rw [hg i hi, zero_smul]
#align fintype.linear_independent_iff Fintype.linearIndependent_iff
theorem Fintype.linearIndependent_iff' [Fintype ι] [DecidableEq ι] :
LinearIndependent R v ↔
LinearMap.ker (LinearMap.lsum R (fun _ ↦ R) ℕ fun i ↦ LinearMap.id.smulRight (v i)) = ⊥ := by
simp [Fintype.linearIndependent_iff, LinearMap.ker_eq_bot', funext_iff]
#align fintype.linear_independent_iff' Fintype.linearIndependent_iff'
| Mathlib/LinearAlgebra/LinearIndependent.lean | 192 | 194 | theorem Fintype.not_linearIndependent_iff [Fintype ι] :
¬LinearIndependent R v ↔ ∃ g : ι → R, ∑ i, g i • v i = 0 ∧ ∃ i, g i ≠ 0 := by |
simpa using not_iff_not.2 Fintype.linearIndependent_iff
|
import Mathlib.RingTheory.Derivation.ToSquareZero
import Mathlib.RingTheory.Ideal.Cotangent
import Mathlib.RingTheory.IsTensorProduct
import Mathlib.Algebra.Exact
import Mathlib.Algebra.MvPolynomial.PDeriv
import Mathlib.Algebra.Polynomial.Derivation
#align_import ring_theory.kaehler from "leanprover-community/mathlib"@"4b92a463033b5587bb011657e25e4710bfca7364"
suppress_compilation
section KaehlerDifferential
open scoped TensorProduct
open Algebra
universe u v
variable (R : Type u) (S : Type v) [CommRing R] [CommRing S] [Algebra R S]
abbrev KaehlerDifferential.ideal : Ideal (S ⊗[R] S) :=
RingHom.ker (TensorProduct.lmul' R : S ⊗[R] S →ₐ[R] S)
#align kaehler_differential.ideal KaehlerDifferential.ideal
variable {S}
theorem KaehlerDifferential.one_smul_sub_smul_one_mem_ideal (a : S) :
(1 : S) ⊗ₜ[R] a - a ⊗ₜ[R] (1 : S) ∈ KaehlerDifferential.ideal R S := by simp [RingHom.mem_ker]
#align kaehler_differential.one_smul_sub_smul_one_mem_ideal KaehlerDifferential.one_smul_sub_smul_one_mem_ideal
variable {R}
variable {M : Type*} [AddCommGroup M] [Module R M] [Module S M] [IsScalarTower R S M]
def Derivation.tensorProductTo (D : Derivation R S M) : S ⊗[R] S →ₗ[S] M :=
TensorProduct.AlgebraTensorModule.lift ((LinearMap.lsmul S (S →ₗ[R] M)).flip D.toLinearMap)
#align derivation.tensor_product_to Derivation.tensorProductTo
theorem Derivation.tensorProductTo_tmul (D : Derivation R S M) (s t : S) :
D.tensorProductTo (s ⊗ₜ t) = s • D t := rfl
#align derivation.tensor_product_to_tmul Derivation.tensorProductTo_tmul
theorem Derivation.tensorProductTo_mul (D : Derivation R S M) (x y : S ⊗[R] S) :
D.tensorProductTo (x * y) =
TensorProduct.lmul' (S := S) R x • D.tensorProductTo y +
TensorProduct.lmul' (S := S) R y • D.tensorProductTo x := by
refine TensorProduct.induction_on x ?_ ?_ ?_
· rw [zero_mul, map_zero, map_zero, zero_smul, smul_zero, add_zero]
swap
· intro x₁ y₁ h₁ h₂
rw [add_mul, map_add, map_add, map_add, add_smul, smul_add, h₁, h₂, add_add_add_comm]
intro x₁ x₂
refine TensorProduct.induction_on y ?_ ?_ ?_
· rw [mul_zero, map_zero, map_zero, zero_smul, smul_zero, add_zero]
swap
· intro x₁ y₁ h₁ h₂
rw [mul_add, map_add, map_add, map_add, add_smul, smul_add, h₁, h₂, add_add_add_comm]
intro x y
simp only [TensorProduct.tmul_mul_tmul, Derivation.tensorProductTo,
TensorProduct.AlgebraTensorModule.lift_apply, TensorProduct.lift.tmul',
TensorProduct.lmul'_apply_tmul]
dsimp
rw [D.leibniz]
simp only [smul_smul, smul_add, mul_comm (x * y) x₁, mul_right_comm x₁ x₂, ← mul_assoc]
#align derivation.tensor_product_to_mul Derivation.tensorProductTo_mul
variable (R S)
theorem KaehlerDifferential.submodule_span_range_eq_ideal :
Submodule.span S (Set.range fun s : S => (1 : S) ⊗ₜ[R] s - s ⊗ₜ[R] (1 : S)) =
(KaehlerDifferential.ideal R S).restrictScalars S := by
apply le_antisymm
· rw [Submodule.span_le]
rintro _ ⟨s, rfl⟩
exact KaehlerDifferential.one_smul_sub_smul_one_mem_ideal _ _
· rintro x (hx : _ = _)
have : x - TensorProduct.lmul' (S := S) R x ⊗ₜ[R] (1 : S) = x := by
rw [hx, TensorProduct.zero_tmul, sub_zero]
rw [← this]
clear this hx
refine TensorProduct.induction_on x ?_ ?_ ?_
· rw [map_zero, TensorProduct.zero_tmul, sub_zero]; exact zero_mem _
· intro x y
have : x ⊗ₜ[R] y - (x * y) ⊗ₜ[R] (1 : S) = x • ((1 : S) ⊗ₜ y - y ⊗ₜ (1 : S)) := by
simp_rw [smul_sub, TensorProduct.smul_tmul', smul_eq_mul, mul_one]
rw [TensorProduct.lmul'_apply_tmul, this]
refine Submodule.smul_mem _ x ?_
apply Submodule.subset_span
exact Set.mem_range_self y
· intro x y hx hy
rw [map_add, TensorProduct.add_tmul, ← sub_add_sub_comm]
exact add_mem hx hy
#align kaehler_differential.submodule_span_range_eq_ideal KaehlerDifferential.submodule_span_range_eq_ideal
theorem KaehlerDifferential.span_range_eq_ideal :
Ideal.span (Set.range fun s : S => (1 : S) ⊗ₜ[R] s - s ⊗ₜ[R] (1 : S)) =
KaehlerDifferential.ideal R S := by
apply le_antisymm
· rw [Ideal.span_le]
rintro _ ⟨s, rfl⟩
exact KaehlerDifferential.one_smul_sub_smul_one_mem_ideal _ _
· change (KaehlerDifferential.ideal R S).restrictScalars S ≤ (Ideal.span _).restrictScalars S
rw [← KaehlerDifferential.submodule_span_range_eq_ideal, Ideal.span]
conv_rhs => rw [← Submodule.span_span_of_tower S]
exact Submodule.subset_span
#align kaehler_differential.span_range_eq_ideal KaehlerDifferential.span_range_eq_ideal
def KaehlerDifferential : Type v :=
(KaehlerDifferential.ideal R S).Cotangent
#align kaehler_differential KaehlerDifferential
instance : AddCommGroup (KaehlerDifferential R S) := by
unfold KaehlerDifferential
infer_instance
instance KaehlerDifferential.module : Module (S ⊗[R] S) (KaehlerDifferential R S) :=
Ideal.Cotangent.moduleOfTower _
#align kaehler_differential.module KaehlerDifferential.module
@[inherit_doc KaehlerDifferential]
notation:100 "Ω[" S "⁄" R "]" => KaehlerDifferential R S
instance : Nonempty (Ω[S⁄R]) := ⟨0⟩
instance KaehlerDifferential.module' {R' : Type*} [CommRing R'] [Algebra R' S]
[SMulCommClass R R' S] :
Module R' (Ω[S⁄R]) :=
Submodule.Quotient.module' _
#align kaehler_differential.module' KaehlerDifferential.module'
instance : IsScalarTower S (S ⊗[R] S) (Ω[S⁄R]) :=
Ideal.Cotangent.isScalarTower _
instance KaehlerDifferential.isScalarTower_of_tower {R₁ R₂ : Type*} [CommRing R₁] [CommRing R₂]
[Algebra R₁ S] [Algebra R₂ S] [SMul R₁ R₂]
[SMulCommClass R R₁ S] [SMulCommClass R R₂ S] [IsScalarTower R₁ R₂ S] :
IsScalarTower R₁ R₂ (Ω[S⁄R]) :=
Submodule.Quotient.isScalarTower _ _
#align kaehler_differential.is_scalar_tower_of_tower KaehlerDifferential.isScalarTower_of_tower
instance KaehlerDifferential.isScalarTower' : IsScalarTower R (S ⊗[R] S) (Ω[S⁄R]) :=
Submodule.Quotient.isScalarTower _ _
#align kaehler_differential.is_scalar_tower' KaehlerDifferential.isScalarTower'
def KaehlerDifferential.fromIdeal : KaehlerDifferential.ideal R S →ₗ[S ⊗[R] S] Ω[S⁄R] :=
(KaehlerDifferential.ideal R S).toCotangent
#align kaehler_differential.from_ideal KaehlerDifferential.fromIdeal
def KaehlerDifferential.DLinearMap : S →ₗ[R] Ω[S⁄R] :=
((KaehlerDifferential.fromIdeal R S).restrictScalars R).comp
((TensorProduct.includeRight.toLinearMap - TensorProduct.includeLeft.toLinearMap :
S →ₗ[R] S ⊗[R] S).codRestrict
((KaehlerDifferential.ideal R S).restrictScalars R)
(KaehlerDifferential.one_smul_sub_smul_one_mem_ideal R) :
_ →ₗ[R] _)
set_option linter.uppercaseLean3 false in
#align kaehler_differential.D_linear_map KaehlerDifferential.DLinearMap
theorem KaehlerDifferential.DLinearMap_apply (s : S) :
KaehlerDifferential.DLinearMap R S s =
(KaehlerDifferential.ideal R S).toCotangent
⟨1 ⊗ₜ s - s ⊗ₜ 1, KaehlerDifferential.one_smul_sub_smul_one_mem_ideal R s⟩ := rfl
set_option linter.uppercaseLean3 false in
#align kaehler_differential.D_linear_map_apply KaehlerDifferential.DLinearMap_apply
def KaehlerDifferential.D : Derivation R S (Ω[S⁄R]) :=
{ toLinearMap := KaehlerDifferential.DLinearMap R S
map_one_eq_zero' := by
dsimp [KaehlerDifferential.DLinearMap_apply, Ideal.toCotangent_apply]
congr
rw [sub_self]
leibniz' := fun a b => by
have : LinearMap.CompatibleSMul { x // x ∈ ideal R S } (Ω[S⁄R]) S (S ⊗[R] S) := inferInstance
dsimp [KaehlerDifferential.DLinearMap_apply]
-- This used to be `rw`, but we need `erw` after leanprover/lean4#2644
erw [← LinearMap.map_smul_of_tower (M₂ := Ω[S⁄R]),
← LinearMap.map_smul_of_tower (M₂ := Ω[S⁄R]), ← map_add, Ideal.toCotangent_eq, pow_two]
convert Submodule.mul_mem_mul (KaehlerDifferential.one_smul_sub_smul_one_mem_ideal R a : _)
(KaehlerDifferential.one_smul_sub_smul_one_mem_ideal R b : _) using 1
simp only [AddSubgroupClass.coe_sub, Submodule.coe_add, Submodule.coe_mk,
TensorProduct.tmul_mul_tmul, mul_sub, sub_mul, mul_comm b, Submodule.coe_smul_of_tower,
smul_sub, TensorProduct.smul_tmul', smul_eq_mul, mul_one]
ring_nf }
set_option linter.uppercaseLean3 false in
#align kaehler_differential.D KaehlerDifferential.D
theorem KaehlerDifferential.D_apply (s : S) :
KaehlerDifferential.D R S s =
(KaehlerDifferential.ideal R S).toCotangent
⟨1 ⊗ₜ s - s ⊗ₜ 1, KaehlerDifferential.one_smul_sub_smul_one_mem_ideal R s⟩ := rfl
set_option linter.uppercaseLean3 false in
#align kaehler_differential.D_apply KaehlerDifferential.D_apply
| Mathlib/RingTheory/Kaehler.lean | 242 | 261 | theorem KaehlerDifferential.span_range_derivation :
Submodule.span S (Set.range <| KaehlerDifferential.D R S) = ⊤ := by |
rw [_root_.eq_top_iff]
rintro x -
obtain ⟨⟨x, hx⟩, rfl⟩ := Ideal.toCotangent_surjective _ x
have : x ∈ (KaehlerDifferential.ideal R S).restrictScalars S := hx
rw [← KaehlerDifferential.submodule_span_range_eq_ideal] at this
suffices ∃ hx, (KaehlerDifferential.ideal R S).toCotangent ⟨x, hx⟩ ∈
Submodule.span S (Set.range <| KaehlerDifferential.D R S) by
exact this.choose_spec
refine Submodule.span_induction this ?_ ?_ ?_ ?_
· rintro _ ⟨x, rfl⟩
refine ⟨KaehlerDifferential.one_smul_sub_smul_one_mem_ideal R x, ?_⟩
apply Submodule.subset_span
exact ⟨x, KaehlerDifferential.DLinearMap_apply R S x⟩
· exact ⟨zero_mem _, Submodule.zero_mem _⟩
· rintro x y ⟨hx₁, hx₂⟩ ⟨hy₁, hy₂⟩; exact ⟨add_mem hx₁ hy₁, Submodule.add_mem _ hx₂ hy₂⟩
· rintro r x ⟨hx₁, hx₂⟩;
exact ⟨((KaehlerDifferential.ideal R S).restrictScalars S).smul_mem r hx₁,
Submodule.smul_mem _ r hx₂⟩
|
import Mathlib.Analysis.Calculus.ContDiff.Defs
import Mathlib.Analysis.Calculus.FDeriv.Add
import Mathlib.Analysis.Calculus.FDeriv.Mul
import Mathlib.Analysis.Calculus.Deriv.Inverse
#align_import analysis.calculus.cont_diff from "leanprover-community/mathlib"@"3bce8d800a6f2b8f63fe1e588fd76a9ff4adcebe"
noncomputable section
open scoped Classical NNReal Nat
local notation "∞" => (⊤ : ℕ∞)
universe u v w uD uE uF uG
attribute [local instance 1001]
NormedAddCommGroup.toAddCommGroup NormedSpace.toModule' AddCommGroup.toAddCommMonoid
open Set Fin Filter Function
open scoped Topology
variable {𝕜 : Type*} [NontriviallyNormedField 𝕜] {D : Type uD} [NormedAddCommGroup D]
[NormedSpace 𝕜 D] {E : Type uE} [NormedAddCommGroup E] [NormedSpace 𝕜 E] {F : Type uF}
[NormedAddCommGroup F] [NormedSpace 𝕜 F] {G : Type uG} [NormedAddCommGroup G] [NormedSpace 𝕜 G]
{X : Type*} [NormedAddCommGroup X] [NormedSpace 𝕜 X] {s s₁ t u : Set E} {f f₁ : E → F}
{g : F → G} {x x₀ : E} {c : F} {b : E × F → G} {m n : ℕ∞} {p : E → FormalMultilinearSeries 𝕜 E F}
@[simp]
theorem iteratedFDerivWithin_zero_fun (hs : UniqueDiffOn 𝕜 s) (hx : x ∈ s) {i : ℕ} :
iteratedFDerivWithin 𝕜 i (fun _ : E ↦ (0 : F)) s x = 0 := by
induction i generalizing x with
| zero => ext; simp
| succ i IH =>
ext m
rw [iteratedFDerivWithin_succ_apply_left, fderivWithin_congr (fun _ ↦ IH) (IH hx)]
rw [fderivWithin_const_apply _ (hs x hx)]
rfl
@[simp]
theorem iteratedFDeriv_zero_fun {n : ℕ} : (iteratedFDeriv 𝕜 n fun _ : E ↦ (0 : F)) = 0 :=
funext fun x ↦ by simpa [← iteratedFDerivWithin_univ] using
iteratedFDerivWithin_zero_fun uniqueDiffOn_univ (mem_univ x)
#align iterated_fderiv_zero_fun iteratedFDeriv_zero_fun
theorem contDiff_zero_fun : ContDiff 𝕜 n fun _ : E => (0 : F) :=
contDiff_of_differentiable_iteratedFDeriv fun m _ => by
rw [iteratedFDeriv_zero_fun]
exact differentiable_const (0 : E[×m]→L[𝕜] F)
#align cont_diff_zero_fun contDiff_zero_fun
theorem contDiff_const {c : F} : ContDiff 𝕜 n fun _ : E => c := by
suffices h : ContDiff 𝕜 ∞ fun _ : E => c from h.of_le le_top
rw [contDiff_top_iff_fderiv]
refine ⟨differentiable_const c, ?_⟩
rw [fderiv_const]
exact contDiff_zero_fun
#align cont_diff_const contDiff_const
theorem contDiffOn_const {c : F} {s : Set E} : ContDiffOn 𝕜 n (fun _ : E => c) s :=
contDiff_const.contDiffOn
#align cont_diff_on_const contDiffOn_const
theorem contDiffAt_const {c : F} : ContDiffAt 𝕜 n (fun _ : E => c) x :=
contDiff_const.contDiffAt
#align cont_diff_at_const contDiffAt_const
theorem contDiffWithinAt_const {c : F} : ContDiffWithinAt 𝕜 n (fun _ : E => c) s x :=
contDiffAt_const.contDiffWithinAt
#align cont_diff_within_at_const contDiffWithinAt_const
@[nontriviality]
theorem contDiff_of_subsingleton [Subsingleton F] : ContDiff 𝕜 n f := by
rw [Subsingleton.elim f fun _ => 0]; exact contDiff_const
#align cont_diff_of_subsingleton contDiff_of_subsingleton
@[nontriviality]
theorem contDiffAt_of_subsingleton [Subsingleton F] : ContDiffAt 𝕜 n f x := by
rw [Subsingleton.elim f fun _ => 0]; exact contDiffAt_const
#align cont_diff_at_of_subsingleton contDiffAt_of_subsingleton
@[nontriviality]
theorem contDiffWithinAt_of_subsingleton [Subsingleton F] : ContDiffWithinAt 𝕜 n f s x := by
rw [Subsingleton.elim f fun _ => 0]; exact contDiffWithinAt_const
#align cont_diff_within_at_of_subsingleton contDiffWithinAt_of_subsingleton
@[nontriviality]
theorem contDiffOn_of_subsingleton [Subsingleton F] : ContDiffOn 𝕜 n f s := by
rw [Subsingleton.elim f fun _ => 0]; exact contDiffOn_const
#align cont_diff_on_of_subsingleton contDiffOn_of_subsingleton
theorem iteratedFDerivWithin_succ_const (n : ℕ) (c : F) (hs : UniqueDiffOn 𝕜 s) (hx : x ∈ s) :
iteratedFDerivWithin 𝕜 (n + 1) (fun _ : E ↦ c) s x = 0 := by
ext m
rw [iteratedFDerivWithin_succ_apply_right hs hx]
rw [iteratedFDerivWithin_congr (fun y hy ↦ fderivWithin_const_apply c (hs y hy)) hx]
rw [iteratedFDerivWithin_zero_fun hs hx]
simp [ContinuousMultilinearMap.zero_apply (R := 𝕜)]
theorem iteratedFDeriv_succ_const (n : ℕ) (c : F) :
(iteratedFDeriv 𝕜 (n + 1) fun _ : E ↦ c) = 0 :=
funext fun x ↦ by simpa [← iteratedFDerivWithin_univ] using
iteratedFDerivWithin_succ_const n c uniqueDiffOn_univ (mem_univ x)
#align iterated_fderiv_succ_const iteratedFDeriv_succ_const
theorem iteratedFDerivWithin_const_of_ne {n : ℕ} (hn : n ≠ 0) (c : F)
(hs : UniqueDiffOn 𝕜 s) (hx : x ∈ s) :
iteratedFDerivWithin 𝕜 n (fun _ : E ↦ c) s x = 0 := by
cases n with
| zero => contradiction
| succ n => exact iteratedFDerivWithin_succ_const n c hs hx
theorem iteratedFDeriv_const_of_ne {n : ℕ} (hn : n ≠ 0) (c : F) :
(iteratedFDeriv 𝕜 n fun _ : E ↦ c) = 0 :=
funext fun x ↦ by simpa [← iteratedFDerivWithin_univ] using
iteratedFDerivWithin_const_of_ne hn c uniqueDiffOn_univ (mem_univ x)
#align iterated_fderiv_const_of_ne iteratedFDeriv_const_of_ne
theorem IsBoundedLinearMap.contDiff (hf : IsBoundedLinearMap 𝕜 f) : ContDiff 𝕜 n f := by
suffices h : ContDiff 𝕜 ∞ f from h.of_le le_top
rw [contDiff_top_iff_fderiv]
refine ⟨hf.differentiable, ?_⟩
simp_rw [hf.fderiv]
exact contDiff_const
#align is_bounded_linear_map.cont_diff IsBoundedLinearMap.contDiff
theorem ContinuousLinearMap.contDiff (f : E →L[𝕜] F) : ContDiff 𝕜 n f :=
f.isBoundedLinearMap.contDiff
#align continuous_linear_map.cont_diff ContinuousLinearMap.contDiff
theorem ContinuousLinearEquiv.contDiff (f : E ≃L[𝕜] F) : ContDiff 𝕜 n f :=
(f : E →L[𝕜] F).contDiff
#align continuous_linear_equiv.cont_diff ContinuousLinearEquiv.contDiff
theorem LinearIsometry.contDiff (f : E →ₗᵢ[𝕜] F) : ContDiff 𝕜 n f :=
f.toContinuousLinearMap.contDiff
#align linear_isometry.cont_diff LinearIsometry.contDiff
theorem LinearIsometryEquiv.contDiff (f : E ≃ₗᵢ[𝕜] F) : ContDiff 𝕜 n f :=
(f : E →L[𝕜] F).contDiff
#align linear_isometry_equiv.cont_diff LinearIsometryEquiv.contDiff
theorem contDiff_id : ContDiff 𝕜 n (id : E → E) :=
IsBoundedLinearMap.id.contDiff
#align cont_diff_id contDiff_id
theorem contDiffWithinAt_id {s x} : ContDiffWithinAt 𝕜 n (id : E → E) s x :=
contDiff_id.contDiffWithinAt
#align cont_diff_within_at_id contDiffWithinAt_id
theorem contDiffAt_id {x} : ContDiffAt 𝕜 n (id : E → E) x :=
contDiff_id.contDiffAt
#align cont_diff_at_id contDiffAt_id
theorem contDiffOn_id {s} : ContDiffOn 𝕜 n (id : E → E) s :=
contDiff_id.contDiffOn
#align cont_diff_on_id contDiffOn_id
theorem IsBoundedBilinearMap.contDiff (hb : IsBoundedBilinearMap 𝕜 b) : ContDiff 𝕜 n b := by
suffices h : ContDiff 𝕜 ∞ b from h.of_le le_top
rw [contDiff_top_iff_fderiv]
refine ⟨hb.differentiable, ?_⟩
simp only [hb.fderiv]
exact hb.isBoundedLinearMap_deriv.contDiff
#align is_bounded_bilinear_map.cont_diff IsBoundedBilinearMap.contDiff
theorem HasFTaylorSeriesUpToOn.continuousLinearMap_comp (g : F →L[𝕜] G)
(hf : HasFTaylorSeriesUpToOn n f p s) :
HasFTaylorSeriesUpToOn n (g ∘ f) (fun x k => g.compContinuousMultilinearMap (p x k)) s where
zero_eq x hx := congr_arg g (hf.zero_eq x hx)
fderivWithin m hm x hx := (ContinuousLinearMap.compContinuousMultilinearMapL 𝕜
(fun _ : Fin m => E) F G g).hasFDerivAt.comp_hasFDerivWithinAt x (hf.fderivWithin m hm x hx)
cont m hm := (ContinuousLinearMap.compContinuousMultilinearMapL 𝕜
(fun _ : Fin m => E) F G g).continuous.comp_continuousOn (hf.cont m hm)
#align has_ftaylor_series_up_to_on.continuous_linear_map_comp HasFTaylorSeriesUpToOn.continuousLinearMap_comp
theorem ContDiffWithinAt.continuousLinearMap_comp (g : F →L[𝕜] G)
(hf : ContDiffWithinAt 𝕜 n f s x) : ContDiffWithinAt 𝕜 n (g ∘ f) s x := fun m hm ↦ by
rcases hf m hm with ⟨u, hu, p, hp⟩
exact ⟨u, hu, _, hp.continuousLinearMap_comp g⟩
#align cont_diff_within_at.continuous_linear_map_comp ContDiffWithinAt.continuousLinearMap_comp
theorem ContDiffAt.continuousLinearMap_comp (g : F →L[𝕜] G) (hf : ContDiffAt 𝕜 n f x) :
ContDiffAt 𝕜 n (g ∘ f) x :=
ContDiffWithinAt.continuousLinearMap_comp g hf
#align cont_diff_at.continuous_linear_map_comp ContDiffAt.continuousLinearMap_comp
theorem ContDiffOn.continuousLinearMap_comp (g : F →L[𝕜] G) (hf : ContDiffOn 𝕜 n f s) :
ContDiffOn 𝕜 n (g ∘ f) s := fun x hx => (hf x hx).continuousLinearMap_comp g
#align cont_diff_on.continuous_linear_map_comp ContDiffOn.continuousLinearMap_comp
theorem ContDiff.continuousLinearMap_comp {f : E → F} (g : F →L[𝕜] G) (hf : ContDiff 𝕜 n f) :
ContDiff 𝕜 n fun x => g (f x) :=
contDiffOn_univ.1 <| ContDiffOn.continuousLinearMap_comp _ (contDiffOn_univ.2 hf)
#align cont_diff.continuous_linear_map_comp ContDiff.continuousLinearMap_comp
theorem ContinuousLinearMap.iteratedFDerivWithin_comp_left {f : E → F} (g : F →L[𝕜] G)
(hf : ContDiffOn 𝕜 n f s) (hs : UniqueDiffOn 𝕜 s) (hx : x ∈ s) {i : ℕ} (hi : (i : ℕ∞) ≤ n) :
iteratedFDerivWithin 𝕜 i (g ∘ f) s x =
g.compContinuousMultilinearMap (iteratedFDerivWithin 𝕜 i f s x) :=
(((hf.ftaylorSeriesWithin hs).continuousLinearMap_comp g).eq_iteratedFDerivWithin_of_uniqueDiffOn
hi hs hx).symm
#align continuous_linear_map.iterated_fderiv_within_comp_left ContinuousLinearMap.iteratedFDerivWithin_comp_left
theorem ContinuousLinearMap.iteratedFDeriv_comp_left {f : E → F} (g : F →L[𝕜] G)
(hf : ContDiff 𝕜 n f) (x : E) {i : ℕ} (hi : (i : ℕ∞) ≤ n) :
iteratedFDeriv 𝕜 i (g ∘ f) x = g.compContinuousMultilinearMap (iteratedFDeriv 𝕜 i f x) := by
simp only [← iteratedFDerivWithin_univ]
exact g.iteratedFDerivWithin_comp_left hf.contDiffOn uniqueDiffOn_univ (mem_univ x) hi
#align continuous_linear_map.iterated_fderiv_comp_left ContinuousLinearMap.iteratedFDeriv_comp_left
theorem ContinuousLinearEquiv.iteratedFDerivWithin_comp_left (g : F ≃L[𝕜] G) (f : E → F)
(hs : UniqueDiffOn 𝕜 s) (hx : x ∈ s) (i : ℕ) :
iteratedFDerivWithin 𝕜 i (g ∘ f) s x =
(g : F →L[𝕜] G).compContinuousMultilinearMap (iteratedFDerivWithin 𝕜 i f s x) := by
induction' i with i IH generalizing x
· ext1 m
simp only [Nat.zero_eq, iteratedFDerivWithin_zero_apply, comp_apply,
ContinuousLinearMap.compContinuousMultilinearMap_coe, coe_coe]
· ext1 m
rw [iteratedFDerivWithin_succ_apply_left]
have Z : fderivWithin 𝕜 (iteratedFDerivWithin 𝕜 i (g ∘ f) s) s x =
fderivWithin 𝕜 (g.compContinuousMultilinearMapL (fun _ : Fin i => E) ∘
iteratedFDerivWithin 𝕜 i f s) s x :=
fderivWithin_congr' (@IH) hx
simp_rw [Z]
rw [(g.compContinuousMultilinearMapL fun _ : Fin i => E).comp_fderivWithin (hs x hx)]
simp only [ContinuousLinearMap.coe_comp', ContinuousLinearEquiv.coe_coe, comp_apply,
ContinuousLinearEquiv.compContinuousMultilinearMapL_apply,
ContinuousLinearMap.compContinuousMultilinearMap_coe, EmbeddingLike.apply_eq_iff_eq]
rw [iteratedFDerivWithin_succ_apply_left]
#align continuous_linear_equiv.iterated_fderiv_within_comp_left ContinuousLinearEquiv.iteratedFDerivWithin_comp_left
theorem LinearIsometry.norm_iteratedFDerivWithin_comp_left {f : E → F} (g : F →ₗᵢ[𝕜] G)
(hf : ContDiffOn 𝕜 n f s) (hs : UniqueDiffOn 𝕜 s) (hx : x ∈ s) {i : ℕ} (hi : (i : ℕ∞) ≤ n) :
‖iteratedFDerivWithin 𝕜 i (g ∘ f) s x‖ = ‖iteratedFDerivWithin 𝕜 i f s x‖ := by
have :
iteratedFDerivWithin 𝕜 i (g ∘ f) s x =
g.toContinuousLinearMap.compContinuousMultilinearMap (iteratedFDerivWithin 𝕜 i f s x) :=
g.toContinuousLinearMap.iteratedFDerivWithin_comp_left hf hs hx hi
rw [this]
apply LinearIsometry.norm_compContinuousMultilinearMap
#align linear_isometry.norm_iterated_fderiv_within_comp_left LinearIsometry.norm_iteratedFDerivWithin_comp_left
theorem LinearIsometry.norm_iteratedFDeriv_comp_left {f : E → F} (g : F →ₗᵢ[𝕜] G)
(hf : ContDiff 𝕜 n f) (x : E) {i : ℕ} (hi : (i : ℕ∞) ≤ n) :
‖iteratedFDeriv 𝕜 i (g ∘ f) x‖ = ‖iteratedFDeriv 𝕜 i f x‖ := by
simp only [← iteratedFDerivWithin_univ]
exact g.norm_iteratedFDerivWithin_comp_left hf.contDiffOn uniqueDiffOn_univ (mem_univ x) hi
#align linear_isometry.norm_iterated_fderiv_comp_left LinearIsometry.norm_iteratedFDeriv_comp_left
theorem LinearIsometryEquiv.norm_iteratedFDerivWithin_comp_left (g : F ≃ₗᵢ[𝕜] G) (f : E → F)
(hs : UniqueDiffOn 𝕜 s) (hx : x ∈ s) (i : ℕ) :
‖iteratedFDerivWithin 𝕜 i (g ∘ f) s x‖ = ‖iteratedFDerivWithin 𝕜 i f s x‖ := by
have :
iteratedFDerivWithin 𝕜 i (g ∘ f) s x =
(g : F →L[𝕜] G).compContinuousMultilinearMap (iteratedFDerivWithin 𝕜 i f s x) :=
g.toContinuousLinearEquiv.iteratedFDerivWithin_comp_left f hs hx i
rw [this]
apply LinearIsometry.norm_compContinuousMultilinearMap g.toLinearIsometry
#align linear_isometry_equiv.norm_iterated_fderiv_within_comp_left LinearIsometryEquiv.norm_iteratedFDerivWithin_comp_left
theorem LinearIsometryEquiv.norm_iteratedFDeriv_comp_left (g : F ≃ₗᵢ[𝕜] G) (f : E → F) (x : E)
(i : ℕ) : ‖iteratedFDeriv 𝕜 i (g ∘ f) x‖ = ‖iteratedFDeriv 𝕜 i f x‖ := by
rw [← iteratedFDerivWithin_univ, ← iteratedFDerivWithin_univ]
apply g.norm_iteratedFDerivWithin_comp_left f uniqueDiffOn_univ (mem_univ x) i
#align linear_isometry_equiv.norm_iterated_fderiv_comp_left LinearIsometryEquiv.norm_iteratedFDeriv_comp_left
theorem ContinuousLinearEquiv.comp_contDiffWithinAt_iff (e : F ≃L[𝕜] G) :
ContDiffWithinAt 𝕜 n (e ∘ f) s x ↔ ContDiffWithinAt 𝕜 n f s x :=
⟨fun H => by
simpa only [(· ∘ ·), e.symm.coe_coe, e.symm_apply_apply] using
H.continuousLinearMap_comp (e.symm : G →L[𝕜] F),
fun H => H.continuousLinearMap_comp (e : F →L[𝕜] G)⟩
#align continuous_linear_equiv.comp_cont_diff_within_at_iff ContinuousLinearEquiv.comp_contDiffWithinAt_iff
theorem ContinuousLinearEquiv.comp_contDiffAt_iff (e : F ≃L[𝕜] G) :
ContDiffAt 𝕜 n (e ∘ f) x ↔ ContDiffAt 𝕜 n f x := by
simp only [← contDiffWithinAt_univ, e.comp_contDiffWithinAt_iff]
#align continuous_linear_equiv.comp_cont_diff_at_iff ContinuousLinearEquiv.comp_contDiffAt_iff
theorem ContinuousLinearEquiv.comp_contDiffOn_iff (e : F ≃L[𝕜] G) :
ContDiffOn 𝕜 n (e ∘ f) s ↔ ContDiffOn 𝕜 n f s := by
simp [ContDiffOn, e.comp_contDiffWithinAt_iff]
#align continuous_linear_equiv.comp_cont_diff_on_iff ContinuousLinearEquiv.comp_contDiffOn_iff
| Mathlib/Analysis/Calculus/ContDiff/Basic.lean | 359 | 361 | theorem ContinuousLinearEquiv.comp_contDiff_iff (e : F ≃L[𝕜] G) :
ContDiff 𝕜 n (e ∘ f) ↔ ContDiff 𝕜 n f := by |
simp only [← contDiffOn_univ, e.comp_contDiffOn_iff]
|
import Mathlib.CategoryTheory.EpiMono
import Mathlib.CategoryTheory.Limits.HasLimits
#align_import category_theory.limits.shapes.equalizers from "leanprover-community/mathlib"@"4698e35ca56a0d4fa53aa5639c3364e0a77f4eba"
section
open CategoryTheory Opposite
namespace CategoryTheory.Limits
-- attribute [local tidy] tactic.case_bash -- Porting note: no tidy nor cases_bash
universe v v₂ u u₂
inductive WalkingParallelPair : Type
| zero
| one
deriving DecidableEq, Inhabited
#align category_theory.limits.walking_parallel_pair CategoryTheory.Limits.WalkingParallelPair
open WalkingParallelPair
inductive WalkingParallelPairHom : WalkingParallelPair → WalkingParallelPair → Type
| left : WalkingParallelPairHom zero one
| right : WalkingParallelPairHom zero one
| id (X : WalkingParallelPair) : WalkingParallelPairHom X X
deriving DecidableEq
#align category_theory.limits.walking_parallel_pair_hom CategoryTheory.Limits.WalkingParallelPairHom
attribute [-simp, nolint simpNF] WalkingParallelPairHom.id.sizeOf_spec
instance : Inhabited (WalkingParallelPairHom zero one) where default := WalkingParallelPairHom.left
open WalkingParallelPairHom
def WalkingParallelPairHom.comp :
-- Porting note: changed X Y Z to implicit to match comp fields in precategory
∀ { X Y Z : WalkingParallelPair } (_ : WalkingParallelPairHom X Y)
(_ : WalkingParallelPairHom Y Z), WalkingParallelPairHom X Z
| _, _, _, id _, h => h
| _, _, _, left, id one => left
| _, _, _, right, id one => right
#align category_theory.limits.walking_parallel_pair_hom.comp CategoryTheory.Limits.WalkingParallelPairHom.comp
-- Porting note: adding these since they are simple and aesop couldn't directly prove them
theorem WalkingParallelPairHom.id_comp
{X Y : WalkingParallelPair} (g : WalkingParallelPairHom X Y) : comp (id X) g = g :=
rfl
theorem WalkingParallelPairHom.comp_id
{X Y : WalkingParallelPair} (f : WalkingParallelPairHom X Y) : comp f (id Y) = f := by
cases f <;> rfl
theorem WalkingParallelPairHom.assoc {X Y Z W : WalkingParallelPair}
(f : WalkingParallelPairHom X Y) (g: WalkingParallelPairHom Y Z)
(h : WalkingParallelPairHom Z W) : comp (comp f g) h = comp f (comp g h) := by
cases f <;> cases g <;> cases h <;> rfl
instance walkingParallelPairHomCategory : SmallCategory WalkingParallelPair where
Hom := WalkingParallelPairHom
id := id
comp := comp
comp_id := comp_id
id_comp := id_comp
assoc := assoc
#align category_theory.limits.walking_parallel_pair_hom_category CategoryTheory.Limits.walkingParallelPairHomCategory
@[simp]
theorem walkingParallelPairHom_id (X : WalkingParallelPair) : WalkingParallelPairHom.id X = 𝟙 X :=
rfl
#align category_theory.limits.walking_parallel_pair_hom_id CategoryTheory.Limits.walkingParallelPairHom_id
-- Porting note: simpNF asked me to do this because the LHS of the non-primed version reduced
@[simp]
theorem WalkingParallelPairHom.id.sizeOf_spec' (X : WalkingParallelPair) :
(WalkingParallelPairHom._sizeOf_inst X X).sizeOf (𝟙 X) = 1 + sizeOf X := by cases X <;> rfl
def walkingParallelPairOp : WalkingParallelPair ⥤ WalkingParallelPairᵒᵖ where
obj x := op <| by cases x; exacts [one, zero]
map f := by
cases f <;> apply Quiver.Hom.op
exacts [left, right, WalkingParallelPairHom.id _]
map_comp := by rintro _ _ _ (_|_|_) g <;> cases g <;> rfl
#align category_theory.limits.walking_parallel_pair_op CategoryTheory.Limits.walkingParallelPairOp
@[simp]
theorem walkingParallelPairOp_zero : walkingParallelPairOp.obj zero = op one := rfl
#align category_theory.limits.walking_parallel_pair_op_zero CategoryTheory.Limits.walkingParallelPairOp_zero
@[simp]
theorem walkingParallelPairOp_one : walkingParallelPairOp.obj one = op zero := rfl
#align category_theory.limits.walking_parallel_pair_op_one CategoryTheory.Limits.walkingParallelPairOp_one
@[simp]
theorem walkingParallelPairOp_left :
walkingParallelPairOp.map left = @Quiver.Hom.op _ _ zero one left := rfl
#align category_theory.limits.walking_parallel_pair_op_left CategoryTheory.Limits.walkingParallelPairOp_left
@[simp]
theorem walkingParallelPairOp_right :
walkingParallelPairOp.map right = @Quiver.Hom.op _ _ zero one right := rfl
#align category_theory.limits.walking_parallel_pair_op_right CategoryTheory.Limits.walkingParallelPairOp_right
@[simps functor inverse]
def walkingParallelPairOpEquiv : WalkingParallelPair ≌ WalkingParallelPairᵒᵖ where
functor := walkingParallelPairOp
inverse := walkingParallelPairOp.leftOp
unitIso :=
NatIso.ofComponents (fun j => eqToIso (by cases j <;> rfl))
(by rintro _ _ (_ | _ | _) <;> simp)
counitIso :=
NatIso.ofComponents (fun j => eqToIso (by
induction' j with X
cases X <;> rfl))
(fun {i} {j} f => by
induction' i with i
induction' j with j
let g := f.unop
have : f = g.op := rfl
rw [this]
cases i <;> cases j <;> cases g <;> rfl)
functor_unitIso_comp := fun j => by cases j <;> rfl
#align category_theory.limits.walking_parallel_pair_op_equiv CategoryTheory.Limits.walkingParallelPairOpEquiv
@[simp]
theorem walkingParallelPairOpEquiv_unitIso_zero :
walkingParallelPairOpEquiv.unitIso.app zero = Iso.refl zero := rfl
#align category_theory.limits.walking_parallel_pair_op_equiv_unit_iso_zero CategoryTheory.Limits.walkingParallelPairOpEquiv_unitIso_zero
@[simp]
theorem walkingParallelPairOpEquiv_unitIso_one :
walkingParallelPairOpEquiv.unitIso.app one = Iso.refl one := rfl
#align category_theory.limits.walking_parallel_pair_op_equiv_unit_iso_one CategoryTheory.Limits.walkingParallelPairOpEquiv_unitIso_one
@[simp]
theorem walkingParallelPairOpEquiv_counitIso_zero :
walkingParallelPairOpEquiv.counitIso.app (op zero) = Iso.refl (op zero) := rfl
#align category_theory.limits.walking_parallel_pair_op_equiv_counit_iso_zero CategoryTheory.Limits.walkingParallelPairOpEquiv_counitIso_zero
@[simp]
theorem walkingParallelPairOpEquiv_counitIso_one :
walkingParallelPairOpEquiv.counitIso.app (op one) = Iso.refl (op one) :=
rfl
#align category_theory.limits.walking_parallel_pair_op_equiv_counit_iso_one CategoryTheory.Limits.walkingParallelPairOpEquiv_counitIso_one
variable {C : Type u} [Category.{v} C]
variable {X Y : C}
def parallelPair (f g : X ⟶ Y) : WalkingParallelPair ⥤ C where
obj x :=
match x with
| zero => X
| one => Y
map h :=
match h with
| WalkingParallelPairHom.id _ => 𝟙 _
| left => f
| right => g
-- `sorry` can cope with this, but it's too slow:
map_comp := by
rintro _ _ _ ⟨⟩ g <;> cases g <;> {dsimp; simp}
#align category_theory.limits.parallel_pair CategoryTheory.Limits.parallelPair
@[simp]
theorem parallelPair_obj_zero (f g : X ⟶ Y) : (parallelPair f g).obj zero = X := rfl
#align category_theory.limits.parallel_pair_obj_zero CategoryTheory.Limits.parallelPair_obj_zero
@[simp]
theorem parallelPair_obj_one (f g : X ⟶ Y) : (parallelPair f g).obj one = Y := rfl
#align category_theory.limits.parallel_pair_obj_one CategoryTheory.Limits.parallelPair_obj_one
@[simp]
theorem parallelPair_map_left (f g : X ⟶ Y) : (parallelPair f g).map left = f := rfl
#align category_theory.limits.parallel_pair_map_left CategoryTheory.Limits.parallelPair_map_left
@[simp]
theorem parallelPair_map_right (f g : X ⟶ Y) : (parallelPair f g).map right = g := rfl
#align category_theory.limits.parallel_pair_map_right CategoryTheory.Limits.parallelPair_map_right
@[simp]
theorem parallelPair_functor_obj {F : WalkingParallelPair ⥤ C} (j : WalkingParallelPair) :
(parallelPair (F.map left) (F.map right)).obj j = F.obj j := by cases j <;> rfl
#align category_theory.limits.parallel_pair_functor_obj CategoryTheory.Limits.parallelPair_functor_obj
@[simps!]
def diagramIsoParallelPair (F : WalkingParallelPair ⥤ C) :
F ≅ parallelPair (F.map left) (F.map right) :=
NatIso.ofComponents (fun j => eqToIso <| by cases j <;> rfl) (by rintro _ _ (_|_|_) <;> simp)
#align category_theory.limits.diagram_iso_parallel_pair CategoryTheory.Limits.diagramIsoParallelPair
def parallelPairHom {X' Y' : C} (f g : X ⟶ Y) (f' g' : X' ⟶ Y') (p : X ⟶ X') (q : Y ⟶ Y')
(wf : f ≫ q = p ≫ f') (wg : g ≫ q = p ≫ g') : parallelPair f g ⟶ parallelPair f' g' where
app j :=
match j with
| zero => p
| one => q
naturality := by
rintro _ _ ⟨⟩ <;> {dsimp; simp [wf,wg]}
#align category_theory.limits.parallel_pair_hom CategoryTheory.Limits.parallelPairHom
@[simp]
theorem parallelPairHom_app_zero {X' Y' : C} (f g : X ⟶ Y) (f' g' : X' ⟶ Y') (p : X ⟶ X')
(q : Y ⟶ Y') (wf : f ≫ q = p ≫ f') (wg : g ≫ q = p ≫ g') :
(parallelPairHom f g f' g' p q wf wg).app zero = p :=
rfl
#align category_theory.limits.parallel_pair_hom_app_zero CategoryTheory.Limits.parallelPairHom_app_zero
@[simp]
theorem parallelPairHom_app_one {X' Y' : C} (f g : X ⟶ Y) (f' g' : X' ⟶ Y') (p : X ⟶ X')
(q : Y ⟶ Y') (wf : f ≫ q = p ≫ f') (wg : g ≫ q = p ≫ g') :
(parallelPairHom f g f' g' p q wf wg).app one = q :=
rfl
#align category_theory.limits.parallel_pair_hom_app_one CategoryTheory.Limits.parallelPairHom_app_one
@[simps!]
def parallelPair.ext {F G : WalkingParallelPair ⥤ C} (zero : F.obj zero ≅ G.obj zero)
(one : F.obj one ≅ G.obj one) (left : F.map left ≫ one.hom = zero.hom ≫ G.map left)
(right : F.map right ≫ one.hom = zero.hom ≫ G.map right) : F ≅ G :=
NatIso.ofComponents
(by
rintro ⟨j⟩
exacts [zero, one])
(by rintro _ _ ⟨_⟩ <;> simp [left, right])
#align category_theory.limits.parallel_pair.ext CategoryTheory.Limits.parallelPair.ext
@[simps!]
def parallelPair.eqOfHomEq {f g f' g' : X ⟶ Y} (hf : f = f') (hg : g = g') :
parallelPair f g ≅ parallelPair f' g' :=
parallelPair.ext (Iso.refl _) (Iso.refl _) (by simp [hf]) (by simp [hg])
#align category_theory.limits.parallel_pair.eq_of_hom_eq CategoryTheory.Limits.parallelPair.eqOfHomEq
abbrev Fork (f g : X ⟶ Y) :=
Cone (parallelPair f g)
#align category_theory.limits.fork CategoryTheory.Limits.Fork
abbrev Cofork (f g : X ⟶ Y) :=
Cocone (parallelPair f g)
#align category_theory.limits.cofork CategoryTheory.Limits.Cofork
variable {f g : X ⟶ Y}
def Fork.ι (t : Fork f g) :=
t.π.app zero
#align category_theory.limits.fork.ι CategoryTheory.Limits.Fork.ι
@[simp]
theorem Fork.app_zero_eq_ι (t : Fork f g) : t.π.app zero = t.ι :=
rfl
#align category_theory.limits.fork.app_zero_eq_ι CategoryTheory.Limits.Fork.app_zero_eq_ι
def Cofork.π (t : Cofork f g) :=
t.ι.app one
#align category_theory.limits.cofork.π CategoryTheory.Limits.Cofork.π
@[simp]
theorem Cofork.app_one_eq_π (t : Cofork f g) : t.ι.app one = t.π :=
rfl
#align category_theory.limits.cofork.app_one_eq_π CategoryTheory.Limits.Cofork.app_one_eq_π
@[simp]
theorem Fork.app_one_eq_ι_comp_left (s : Fork f g) : s.π.app one = s.ι ≫ f := by
rw [← s.app_zero_eq_ι, ← s.w left, parallelPair_map_left]
#align category_theory.limits.fork.app_one_eq_ι_comp_left CategoryTheory.Limits.Fork.app_one_eq_ι_comp_left
@[reassoc]
theorem Fork.app_one_eq_ι_comp_right (s : Fork f g) : s.π.app one = s.ι ≫ g := by
rw [← s.app_zero_eq_ι, ← s.w right, parallelPair_map_right]
#align category_theory.limits.fork.app_one_eq_ι_comp_right CategoryTheory.Limits.Fork.app_one_eq_ι_comp_right
@[simp]
theorem Cofork.app_zero_eq_comp_π_left (s : Cofork f g) : s.ι.app zero = f ≫ s.π := by
rw [← s.app_one_eq_π, ← s.w left, parallelPair_map_left]
#align category_theory.limits.cofork.app_zero_eq_comp_π_left CategoryTheory.Limits.Cofork.app_zero_eq_comp_π_left
@[reassoc]
theorem Cofork.app_zero_eq_comp_π_right (s : Cofork f g) : s.ι.app zero = g ≫ s.π := by
rw [← s.app_one_eq_π, ← s.w right, parallelPair_map_right]
#align category_theory.limits.cofork.app_zero_eq_comp_π_right CategoryTheory.Limits.Cofork.app_zero_eq_comp_π_right
@[simps]
def Fork.ofι {P : C} (ι : P ⟶ X) (w : ι ≫ f = ι ≫ g) : Fork f g where
pt := P
π :=
{ app := fun X => by
cases X
· exact ι
· exact ι ≫ f
naturality := fun {X} {Y} f =>
by cases X <;> cases Y <;> cases f <;> dsimp <;> simp; assumption }
#align category_theory.limits.fork.of_ι CategoryTheory.Limits.Fork.ofι
@[simps]
def Cofork.ofπ {P : C} (π : Y ⟶ P) (w : f ≫ π = g ≫ π) : Cofork f g where
pt := P
ι :=
{ app := fun X => WalkingParallelPair.casesOn X (f ≫ π) π
naturality := fun i j f => by cases f <;> dsimp <;> simp [w] }
#align category_theory.limits.cofork.of_π CategoryTheory.Limits.Cofork.ofπ
-- See note [dsimp, simp]
@[simp]
theorem Fork.ι_ofι {P : C} (ι : P ⟶ X) (w : ι ≫ f = ι ≫ g) : (Fork.ofι ι w).ι = ι :=
rfl
#align category_theory.limits.fork.ι_of_ι CategoryTheory.Limits.Fork.ι_ofι
@[simp]
theorem Cofork.π_ofπ {P : C} (π : Y ⟶ P) (w : f ≫ π = g ≫ π) : (Cofork.ofπ π w).π = π :=
rfl
#align category_theory.limits.cofork.π_of_π CategoryTheory.Limits.Cofork.π_ofπ
@[reassoc (attr := simp)]
theorem Fork.condition (t : Fork f g) : t.ι ≫ f = t.ι ≫ g := by
rw [← t.app_one_eq_ι_comp_left, ← t.app_one_eq_ι_comp_right]
#align category_theory.limits.fork.condition CategoryTheory.Limits.Fork.condition
@[reassoc (attr := simp)]
theorem Cofork.condition (t : Cofork f g) : f ≫ t.π = g ≫ t.π := by
rw [← t.app_zero_eq_comp_π_left, ← t.app_zero_eq_comp_π_right]
#align category_theory.limits.cofork.condition CategoryTheory.Limits.Cofork.condition
theorem Fork.equalizer_ext (s : Fork f g) {W : C} {k l : W ⟶ s.pt} (h : k ≫ s.ι = l ≫ s.ι) :
∀ j : WalkingParallelPair, k ≫ s.π.app j = l ≫ s.π.app j
| zero => h
| one => by
have : k ≫ ι s ≫ f = l ≫ ι s ≫ f := by
simp only [← Category.assoc]; exact congrArg (· ≫ f) h
rw [s.app_one_eq_ι_comp_left, this]
#align category_theory.limits.fork.equalizer_ext CategoryTheory.Limits.Fork.equalizer_ext
theorem Cofork.coequalizer_ext (s : Cofork f g) {W : C} {k l : s.pt ⟶ W}
(h : Cofork.π s ≫ k = Cofork.π s ≫ l) : ∀ j : WalkingParallelPair, s.ι.app j ≫ k = s.ι.app j ≫ l
| zero => by simp only [s.app_zero_eq_comp_π_left, Category.assoc, h]
| one => h
#align category_theory.limits.cofork.coequalizer_ext CategoryTheory.Limits.Cofork.coequalizer_ext
theorem Fork.IsLimit.hom_ext {s : Fork f g} (hs : IsLimit s) {W : C} {k l : W ⟶ s.pt}
(h : k ≫ Fork.ι s = l ≫ Fork.ι s) : k = l :=
hs.hom_ext <| Fork.equalizer_ext _ h
#align category_theory.limits.fork.is_limit.hom_ext CategoryTheory.Limits.Fork.IsLimit.hom_ext
theorem Cofork.IsColimit.hom_ext {s : Cofork f g} (hs : IsColimit s) {W : C} {k l : s.pt ⟶ W}
(h : Cofork.π s ≫ k = Cofork.π s ≫ l) : k = l :=
hs.hom_ext <| Cofork.coequalizer_ext _ h
#align category_theory.limits.cofork.is_colimit.hom_ext CategoryTheory.Limits.Cofork.IsColimit.hom_ext
@[reassoc (attr := simp)]
theorem Fork.IsLimit.lift_ι {s t : Fork f g} (hs : IsLimit s) : hs.lift t ≫ s.ι = t.ι :=
hs.fac _ _
#align category_theory.limits.fork.is_limit.lift_ι CategoryTheory.Limits.Fork.IsLimit.lift_ι
@[reassoc (attr := simp)]
theorem Cofork.IsColimit.π_desc {s t : Cofork f g} (hs : IsColimit s) : s.π ≫ hs.desc t = t.π :=
hs.fac _ _
#align category_theory.limits.cofork.is_colimit.π_desc CategoryTheory.Limits.Cofork.IsColimit.π_desc
-- Porting note: `Fork.IsLimit.lift` was added in order to ease the port
def Fork.IsLimit.lift {s : Fork f g} (hs : IsLimit s) {W : C} (k : W ⟶ X) (h : k ≫ f = k ≫ g) :
W ⟶ s.pt :=
hs.lift (Fork.ofι _ h)
@[reassoc (attr := simp)]
lemma Fork.IsLimit.lift_ι' {s : Fork f g} (hs : IsLimit s) {W : C} (k : W ⟶ X) (h : k ≫ f = k ≫ g) :
Fork.IsLimit.lift hs k h ≫ Fork.ι s = k :=
hs.fac _ _
def Fork.IsLimit.lift' {s : Fork f g} (hs : IsLimit s) {W : C} (k : W ⟶ X) (h : k ≫ f = k ≫ g) :
{ l : W ⟶ s.pt // l ≫ Fork.ι s = k } :=
⟨Fork.IsLimit.lift hs k h, by simp⟩
#align category_theory.limits.fork.is_limit.lift' CategoryTheory.Limits.Fork.IsLimit.lift'
-- Porting note: `Cofork.IsColimit.desc` was added in order to ease the port
def Cofork.IsColimit.desc {s : Cofork f g} (hs : IsColimit s) {W : C} (k : Y ⟶ W)
(h : f ≫ k = g ≫ k) : s.pt ⟶ W :=
hs.desc (Cofork.ofπ _ h)
@[reassoc (attr := simp)]
lemma Cofork.IsColimit.π_desc' {s : Cofork f g} (hs : IsColimit s) {W : C} (k : Y ⟶ W)
(h : f ≫ k = g ≫ k) : Cofork.π s ≫ Cofork.IsColimit.desc hs k h = k :=
hs.fac _ _
def Cofork.IsColimit.desc' {s : Cofork f g} (hs : IsColimit s) {W : C} (k : Y ⟶ W)
(h : f ≫ k = g ≫ k) : { l : s.pt ⟶ W // Cofork.π s ≫ l = k } :=
⟨Cofork.IsColimit.desc hs k h, by simp⟩
#align category_theory.limits.cofork.is_colimit.desc' CategoryTheory.Limits.Cofork.IsColimit.desc'
theorem Fork.IsLimit.existsUnique {s : Fork f g} (hs : IsLimit s) {W : C} (k : W ⟶ X)
(h : k ≫ f = k ≫ g) : ∃! l : W ⟶ s.pt, l ≫ Fork.ι s = k :=
⟨hs.lift <| Fork.ofι _ h, hs.fac _ _, fun _ hm =>
Fork.IsLimit.hom_ext hs <| hm.symm ▸ (hs.fac (Fork.ofι _ h) WalkingParallelPair.zero).symm⟩
#align category_theory.limits.fork.is_limit.exists_unique CategoryTheory.Limits.Fork.IsLimit.existsUnique
theorem Cofork.IsColimit.existsUnique {s : Cofork f g} (hs : IsColimit s) {W : C} (k : Y ⟶ W)
(h : f ≫ k = g ≫ k) : ∃! d : s.pt ⟶ W, Cofork.π s ≫ d = k :=
⟨hs.desc <| Cofork.ofπ _ h, hs.fac _ _, fun _ hm =>
Cofork.IsColimit.hom_ext hs <| hm.symm ▸ (hs.fac (Cofork.ofπ _ h) WalkingParallelPair.one).symm⟩
#align category_theory.limits.cofork.is_colimit.exists_unique CategoryTheory.Limits.Cofork.IsColimit.existsUnique
@[simps]
def Fork.IsLimit.mk (t : Fork f g) (lift : ∀ s : Fork f g, s.pt ⟶ t.pt)
(fac : ∀ s : Fork f g, lift s ≫ Fork.ι t = Fork.ι s)
(uniq : ∀ (s : Fork f g) (m : s.pt ⟶ t.pt) (_ : m ≫ t.ι = s.ι), m = lift s) : IsLimit t :=
{ lift
fac := fun s j =>
WalkingParallelPair.casesOn j (fac s) <| by
erw [← s.w left, ← t.w left, ← Category.assoc, fac]; rfl
uniq := fun s m j => by aesop}
#align category_theory.limits.fork.is_limit.mk CategoryTheory.Limits.Fork.IsLimit.mk
def Fork.IsLimit.mk' {X Y : C} {f g : X ⟶ Y} (t : Fork f g)
(create : ∀ s : Fork f g, { l // l ≫ t.ι = s.ι ∧ ∀ {m}, m ≫ t.ι = s.ι → m = l }) : IsLimit t :=
Fork.IsLimit.mk t (fun s => (create s).1) (fun s => (create s).2.1) fun s _ w => (create s).2.2 w
#align category_theory.limits.fork.is_limit.mk' CategoryTheory.Limits.Fork.IsLimit.mk'
def Cofork.IsColimit.mk (t : Cofork f g) (desc : ∀ s : Cofork f g, t.pt ⟶ s.pt)
(fac : ∀ s : Cofork f g, Cofork.π t ≫ desc s = Cofork.π s)
(uniq : ∀ (s : Cofork f g) (m : t.pt ⟶ s.pt) (_ : t.π ≫ m = s.π), m = desc s) : IsColimit t :=
{ desc
fac := fun s j =>
WalkingParallelPair.casesOn j (by erw [← s.w left, ← t.w left, Category.assoc, fac]; rfl)
(fac s)
uniq := by aesop }
#align category_theory.limits.cofork.is_colimit.mk CategoryTheory.Limits.Cofork.IsColimit.mk
def Cofork.IsColimit.mk' {X Y : C} {f g : X ⟶ Y} (t : Cofork f g)
(create : ∀ s : Cofork f g, { l : t.pt ⟶ s.pt // t.π ≫ l = s.π
∧ ∀ {m}, t.π ≫ m = s.π → m = l }) : IsColimit t :=
Cofork.IsColimit.mk t (fun s => (create s).1) (fun s => (create s).2.1) fun s _ w =>
(create s).2.2 w
#align category_theory.limits.cofork.is_colimit.mk' CategoryTheory.Limits.Cofork.IsColimit.mk'
noncomputable def Fork.IsLimit.ofExistsUnique {t : Fork f g}
(hs : ∀ s : Fork f g, ∃! l : s.pt ⟶ t.pt, l ≫ Fork.ι t = Fork.ι s) : IsLimit t := by
choose d hd hd' using hs
exact Fork.IsLimit.mk _ d hd fun s m hm => hd' _ _ hm
#align category_theory.limits.fork.is_limit.of_exists_unique CategoryTheory.Limits.Fork.IsLimit.ofExistsUnique
noncomputable def Cofork.IsColimit.ofExistsUnique {t : Cofork f g}
(hs : ∀ s : Cofork f g, ∃! d : t.pt ⟶ s.pt, Cofork.π t ≫ d = Cofork.π s) : IsColimit t := by
choose d hd hd' using hs
exact Cofork.IsColimit.mk _ d hd fun s m hm => hd' _ _ hm
#align category_theory.limits.cofork.is_colimit.of_exists_unique CategoryTheory.Limits.Cofork.IsColimit.ofExistsUnique
@[simps]
def Fork.IsLimit.homIso {X Y : C} {f g : X ⟶ Y} {t : Fork f g} (ht : IsLimit t) (Z : C) :
(Z ⟶ t.pt) ≃ { h : Z ⟶ X // h ≫ f = h ≫ g } where
toFun k := ⟨k ≫ t.ι, by simp only [Category.assoc, t.condition]⟩
invFun h := (Fork.IsLimit.lift' ht _ h.prop).1
left_inv k := Fork.IsLimit.hom_ext ht (Fork.IsLimit.lift' _ _ _).prop
right_inv h := Subtype.ext (Fork.IsLimit.lift' ht _ _).prop
#align category_theory.limits.fork.is_limit.hom_iso CategoryTheory.Limits.Fork.IsLimit.homIso
theorem Fork.IsLimit.homIso_natural {X Y : C} {f g : X ⟶ Y} {t : Fork f g} (ht : IsLimit t)
{Z Z' : C} (q : Z' ⟶ Z) (k : Z ⟶ t.pt) :
(Fork.IsLimit.homIso ht _ (q ≫ k) : Z' ⟶ X) = q ≫ (Fork.IsLimit.homIso ht _ k : Z ⟶ X) :=
Category.assoc _ _ _
#align category_theory.limits.fork.is_limit.hom_iso_natural CategoryTheory.Limits.Fork.IsLimit.homIso_natural
@[simps]
def Cofork.IsColimit.homIso {X Y : C} {f g : X ⟶ Y} {t : Cofork f g} (ht : IsColimit t) (Z : C) :
(t.pt ⟶ Z) ≃ { h : Y ⟶ Z // f ≫ h = g ≫ h } where
toFun k := ⟨t.π ≫ k, by simp only [← Category.assoc, t.condition]⟩
invFun h := (Cofork.IsColimit.desc' ht _ h.prop).1
left_inv k := Cofork.IsColimit.hom_ext ht (Cofork.IsColimit.desc' _ _ _).prop
right_inv h := Subtype.ext (Cofork.IsColimit.desc' ht _ _).prop
#align category_theory.limits.cofork.is_colimit.hom_iso CategoryTheory.Limits.Cofork.IsColimit.homIso
theorem Cofork.IsColimit.homIso_natural {X Y : C} {f g : X ⟶ Y} {t : Cofork f g} {Z Z' : C}
(q : Z ⟶ Z') (ht : IsColimit t) (k : t.pt ⟶ Z) :
(Cofork.IsColimit.homIso ht _ (k ≫ q) : Y ⟶ Z') =
(Cofork.IsColimit.homIso ht _ k : Y ⟶ Z) ≫ q :=
(Category.assoc _ _ _).symm
#align category_theory.limits.cofork.is_colimit.hom_iso_natural CategoryTheory.Limits.Cofork.IsColimit.homIso_natural
def Cone.ofFork {F : WalkingParallelPair ⥤ C} (t : Fork (F.map left) (F.map right)) : Cone F where
pt := t.pt
π :=
{ app := fun X => t.π.app X ≫ eqToHom (by aesop)
naturality := by rintro _ _ (_|_|_) <;> {dsimp; simp [t.condition]}}
#align category_theory.limits.cone.of_fork CategoryTheory.Limits.Cone.ofFork
def Cocone.ofCofork {F : WalkingParallelPair ⥤ C} (t : Cofork (F.map left) (F.map right)) :
Cocone F where
pt := t.pt
ι :=
{ app := fun X => eqToHom (by aesop) ≫ t.ι.app X
naturality := by rintro _ _ (_|_|_) <;> {dsimp; simp [t.condition]}}
#align category_theory.limits.cocone.of_cofork CategoryTheory.Limits.Cocone.ofCofork
@[simp]
theorem Cone.ofFork_π {F : WalkingParallelPair ⥤ C} (t : Fork (F.map left) (F.map right)) (j) :
(Cone.ofFork t).π.app j = t.π.app j ≫ eqToHom (by aesop) := rfl
#align category_theory.limits.cone.of_fork_π CategoryTheory.Limits.Cone.ofFork_π
@[simp]
theorem Cocone.ofCofork_ι {F : WalkingParallelPair ⥤ C} (t : Cofork (F.map left) (F.map right))
(j) : (Cocone.ofCofork t).ι.app j = eqToHom (by aesop) ≫ t.ι.app j := rfl
#align category_theory.limits.cocone.of_cofork_ι CategoryTheory.Limits.Cocone.ofCofork_ι
def Fork.ofCone {F : WalkingParallelPair ⥤ C} (t : Cone F) : Fork (F.map left) (F.map right) where
pt := t.pt
π := { app := fun X => t.π.app X ≫ eqToHom (by aesop)
naturality := by rintro _ _ (_|_|_) <;> {dsimp; simp}}
#align category_theory.limits.fork.of_cone CategoryTheory.Limits.Fork.ofCone
def Cofork.ofCocone {F : WalkingParallelPair ⥤ C} (t : Cocone F) :
Cofork (F.map left) (F.map right) where
pt := t.pt
ι := { app := fun X => eqToHom (by aesop) ≫ t.ι.app X
naturality := by rintro _ _ (_|_|_) <;> {dsimp; simp}}
#align category_theory.limits.cofork.of_cocone CategoryTheory.Limits.Cofork.ofCocone
@[simp]
theorem Fork.ofCone_π {F : WalkingParallelPair ⥤ C} (t : Cone F) (j) :
(Fork.ofCone t).π.app j = t.π.app j ≫ eqToHom (by aesop) := rfl
#align category_theory.limits.fork.of_cone_π CategoryTheory.Limits.Fork.ofCone_π
@[simp]
theorem Cofork.ofCocone_ι {F : WalkingParallelPair ⥤ C} (t : Cocone F) (j) :
(Cofork.ofCocone t).ι.app j = eqToHom (by aesop) ≫ t.ι.app j := rfl
#align category_theory.limits.cofork.of_cocone_ι CategoryTheory.Limits.Cofork.ofCocone_ι
@[simp]
theorem Fork.ι_postcompose {f' g' : X ⟶ Y} {α : parallelPair f g ⟶ parallelPair f' g'}
{c : Fork f g} : Fork.ι ((Cones.postcompose α).obj c) = c.ι ≫ α.app _ :=
rfl
#align category_theory.limits.fork.ι_postcompose CategoryTheory.Limits.Fork.ι_postcompose
@[simp]
theorem Cofork.π_precompose {f' g' : X ⟶ Y} {α : parallelPair f g ⟶ parallelPair f' g'}
{c : Cofork f' g'} : Cofork.π ((Cocones.precompose α).obj c) = α.app _ ≫ c.π :=
rfl
#align category_theory.limits.cofork.π_precompose CategoryTheory.Limits.Cofork.π_precompose
@[simps]
def Fork.mkHom {s t : Fork f g} (k : s.pt ⟶ t.pt) (w : k ≫ t.ι = s.ι) : s ⟶ t where
hom := k
w := by
rintro ⟨_ | _⟩
· exact w
· simp only [Fork.app_one_eq_ι_comp_left,← Category.assoc]
congr
#align category_theory.limits.fork.mk_hom CategoryTheory.Limits.Fork.mkHom
@[simps]
def Fork.ext {s t : Fork f g} (i : s.pt ≅ t.pt) (w : i.hom ≫ t.ι = s.ι := by aesop_cat) :
s ≅ t where
hom := Fork.mkHom i.hom w
inv := Fork.mkHom i.inv (by rw [← w, Iso.inv_hom_id_assoc])
#align category_theory.limits.fork.ext CategoryTheory.Limits.Fork.ext
def ForkOfι.ext {P : C} {ι ι' : P ⟶ X} (w : ι ≫ f = ι ≫ g) (w' : ι' ≫ f = ι' ≫ g) (h : ι = ι') :
Fork.ofι ι w ≅ Fork.ofι ι' w' :=
Fork.ext (Iso.refl _) (by simp [h])
def Fork.isoForkOfι (c : Fork f g) : c ≅ Fork.ofι c.ι c.condition :=
Fork.ext (by simp only [Fork.ofι_pt, Functor.const_obj_obj]; rfl) (by simp)
#align category_theory.limits.fork.iso_fork_of_ι CategoryTheory.Limits.Fork.isoForkOfι
def Fork.isLimitOfIsos {X' Y' : C} (c : Fork f g) (hc : IsLimit c)
{f' g' : X' ⟶ Y'} (c' : Fork f' g')
(e₀ : X ≅ X') (e₁ : Y ≅ Y') (e : c.pt ≅ c'.pt)
(comm₁ : e₀.hom ≫ f' = f ≫ e₁.hom := by aesop_cat)
(comm₂ : e₀.hom ≫ g' = g ≫ e₁.hom := by aesop_cat)
(comm₃ : e.hom ≫ c'.ι = c.ι ≫ e₀.hom := by aesop_cat) : IsLimit c' :=
let i : parallelPair f g ≅ parallelPair f' g' := parallelPair.ext e₀ e₁ comm₁.symm comm₂.symm
(IsLimit.equivOfNatIsoOfIso i c c' (Fork.ext e comm₃)) hc
@[simps]
def Cofork.mkHom {s t : Cofork f g} (k : s.pt ⟶ t.pt) (w : s.π ≫ k = t.π) : s ⟶ t where
hom := k
w := by
rintro ⟨_ | _⟩
· simp [Cofork.app_zero_eq_comp_π_left, w]
· exact w
#align category_theory.limits.cofork.mk_hom CategoryTheory.Limits.Cofork.mkHom
@[reassoc (attr := simp)]
theorem Fork.hom_comp_ι {s t : Fork f g} (f : s ⟶ t) : f.hom ≫ t.ι = s.ι := by
cases s; cases t; cases f; aesop
#align category_theory.limits.fork.hom_comp_ι CategoryTheory.Limits.Fork.hom_comp_ι
@[reassoc (attr := simp)]
theorem Fork.π_comp_hom {s t : Cofork f g} (f : s ⟶ t) : s.π ≫ f.hom = t.π := by
cases s; cases t; cases f; aesop
#align category_theory.limits.fork.π_comp_hom CategoryTheory.Limits.Fork.π_comp_hom
@[simps]
def Cofork.ext {s t : Cofork f g} (i : s.pt ≅ t.pt) (w : s.π ≫ i.hom = t.π := by aesop_cat) :
s ≅ t where
hom := Cofork.mkHom i.hom w
inv := Cofork.mkHom i.inv (by rw [Iso.comp_inv_eq, w])
#align category_theory.limits.cofork.ext CategoryTheory.Limits.Cofork.ext
def Cofork.isoCoforkOfπ (c : Cofork f g) : c ≅ Cofork.ofπ c.π c.condition :=
Cofork.ext (by simp only [Cofork.ofπ_pt, Functor.const_obj_obj]; rfl) (by dsimp; simp)
#align category_theory.limits.cofork.iso_cofork_of_π CategoryTheory.Limits.Cofork.isoCoforkOfπ
variable (f g)
section
abbrev HasEqualizer :=
HasLimit (parallelPair f g)
#align category_theory.limits.has_equalizer CategoryTheory.Limits.HasEqualizer
variable [HasEqualizer f g]
noncomputable abbrev equalizer : C :=
limit (parallelPair f g)
#align category_theory.limits.equalizer CategoryTheory.Limits.equalizer
noncomputable abbrev equalizer.ι : equalizer f g ⟶ X :=
limit.π (parallelPair f g) zero
#align category_theory.limits.equalizer.ι CategoryTheory.Limits.equalizer.ι
noncomputable abbrev equalizer.fork : Fork f g :=
limit.cone (parallelPair f g)
#align category_theory.limits.equalizer.fork CategoryTheory.Limits.equalizer.fork
@[simp]
theorem equalizer.fork_ι : (equalizer.fork f g).ι = equalizer.ι f g :=
rfl
#align category_theory.limits.equalizer.fork_ι CategoryTheory.Limits.equalizer.fork_ι
@[simp]
theorem equalizer.fork_π_app_zero : (equalizer.fork f g).π.app zero = equalizer.ι f g :=
rfl
#align category_theory.limits.equalizer.fork_π_app_zero CategoryTheory.Limits.equalizer.fork_π_app_zero
@[reassoc]
theorem equalizer.condition : equalizer.ι f g ≫ f = equalizer.ι f g ≫ g :=
Fork.condition <| limit.cone <| parallelPair f g
#align category_theory.limits.equalizer.condition CategoryTheory.Limits.equalizer.condition
noncomputable def equalizerIsEqualizer : IsLimit (Fork.ofι (equalizer.ι f g)
(equalizer.condition f g)) :=
IsLimit.ofIsoLimit (limit.isLimit _) (Fork.ext (Iso.refl _) (by aesop))
#align category_theory.limits.equalizer_is_equalizer CategoryTheory.Limits.equalizerIsEqualizer
variable {f g}
noncomputable abbrev equalizer.lift {W : C} (k : W ⟶ X) (h : k ≫ f = k ≫ g) : W ⟶ equalizer f g :=
limit.lift (parallelPair f g) (Fork.ofι k h)
#align category_theory.limits.equalizer.lift CategoryTheory.Limits.equalizer.lift
-- Porting note (#10618): removed simp since simp can prove this and the reassoc version
@[reassoc]
theorem equalizer.lift_ι {W : C} (k : W ⟶ X) (h : k ≫ f = k ≫ g) :
equalizer.lift k h ≫ equalizer.ι f g = k :=
limit.lift_π _ _
#align category_theory.limits.equalizer.lift_ι CategoryTheory.Limits.equalizer.lift_ι
noncomputable def equalizer.lift' {W : C} (k : W ⟶ X) (h : k ≫ f = k ≫ g) :
{ l : W ⟶ equalizer f g // l ≫ equalizer.ι f g = k } :=
⟨equalizer.lift k h, equalizer.lift_ι _ _⟩
#align category_theory.limits.equalizer.lift' CategoryTheory.Limits.equalizer.lift'
@[ext]
theorem equalizer.hom_ext {W : C} {k l : W ⟶ equalizer f g}
(h : k ≫ equalizer.ι f g = l ≫ equalizer.ι f g) : k = l :=
Fork.IsLimit.hom_ext (limit.isLimit _) h
#align category_theory.limits.equalizer.hom_ext CategoryTheory.Limits.equalizer.hom_ext
theorem equalizer.existsUnique {W : C} (k : W ⟶ X) (h : k ≫ f = k ≫ g) :
∃! l : W ⟶ equalizer f g, l ≫ equalizer.ι f g = k :=
Fork.IsLimit.existsUnique (limit.isLimit _) _ h
#align category_theory.limits.equalizer.exists_unique CategoryTheory.Limits.equalizer.existsUnique
instance equalizer.ι_mono : Mono (equalizer.ι f g) where
right_cancellation _ _ w := equalizer.hom_ext w
#align category_theory.limits.equalizer.ι_mono CategoryTheory.Limits.equalizer.ι_mono
end
section
variable {f g}
theorem mono_of_isLimit_fork {c : Fork f g} (i : IsLimit c) : Mono (Fork.ι c) :=
{ right_cancellation := fun _ _ w => Fork.IsLimit.hom_ext i w }
#align category_theory.limits.mono_of_is_limit_fork CategoryTheory.Limits.mono_of_isLimit_fork
end
section
variable {f g}
def idFork (h : f = g) : Fork f g :=
Fork.ofι (𝟙 X) <| h ▸ rfl
#align category_theory.limits.id_fork CategoryTheory.Limits.idFork
def isLimitIdFork (h : f = g) : IsLimit (idFork h) :=
Fork.IsLimit.mk _ (fun s => Fork.ι s) (fun s => Category.comp_id _) fun s m h => by
convert h
exact (Category.comp_id _).symm
#align category_theory.limits.is_limit_id_fork CategoryTheory.Limits.isLimitIdFork
theorem isIso_limit_cone_parallelPair_of_eq (h₀ : f = g) {c : Fork f g} (h : IsLimit c) :
IsIso c.ι :=
Iso.isIso_hom <| IsLimit.conePointUniqueUpToIso h <| isLimitIdFork h₀
#align category_theory.limits.is_iso_limit_cone_parallel_pair_of_eq CategoryTheory.Limits.isIso_limit_cone_parallelPair_of_eq
theorem equalizer.ι_of_eq [HasEqualizer f g] (h : f = g) : IsIso (equalizer.ι f g) :=
isIso_limit_cone_parallelPair_of_eq h <| limit.isLimit _
#align category_theory.limits.equalizer.ι_of_eq CategoryTheory.Limits.equalizer.ι_of_eq
theorem isIso_limit_cone_parallelPair_of_self {c : Fork f f} (h : IsLimit c) : IsIso c.ι :=
isIso_limit_cone_parallelPair_of_eq rfl h
#align category_theory.limits.is_iso_limit_cone_parallel_pair_of_self CategoryTheory.Limits.isIso_limit_cone_parallelPair_of_self
theorem isIso_limit_cone_parallelPair_of_epi {c : Fork f g} (h : IsLimit c) [Epi c.ι] : IsIso c.ι :=
isIso_limit_cone_parallelPair_of_eq ((cancel_epi _).1 (Fork.condition c)) h
#align category_theory.limits.is_iso_limit_cone_parallel_pair_of_epi CategoryTheory.Limits.isIso_limit_cone_parallelPair_of_epi
theorem eq_of_epi_fork_ι (t : Fork f g) [Epi (Fork.ι t)] : f = g :=
(cancel_epi (Fork.ι t)).1 <| Fork.condition t
#align category_theory.limits.eq_of_epi_fork_ι CategoryTheory.Limits.eq_of_epi_fork_ι
theorem eq_of_epi_equalizer [HasEqualizer f g] [Epi (equalizer.ι f g)] : f = g :=
(cancel_epi (equalizer.ι f g)).1 <| equalizer.condition _ _
#align category_theory.limits.eq_of_epi_equalizer CategoryTheory.Limits.eq_of_epi_equalizer
end
instance hasEqualizer_of_self : HasEqualizer f f :=
HasLimit.mk
{ cone := idFork rfl
isLimit := isLimitIdFork rfl }
#align category_theory.limits.has_equalizer_of_self CategoryTheory.Limits.hasEqualizer_of_self
instance equalizer.ι_of_self : IsIso (equalizer.ι f f) :=
equalizer.ι_of_eq rfl
#align category_theory.limits.equalizer.ι_of_self CategoryTheory.Limits.equalizer.ι_of_self
noncomputable def equalizer.isoSourceOfSelf : equalizer f f ≅ X :=
asIso (equalizer.ι f f)
#align category_theory.limits.equalizer.iso_source_of_self CategoryTheory.Limits.equalizer.isoSourceOfSelf
@[simp]
theorem equalizer.isoSourceOfSelf_hom : (equalizer.isoSourceOfSelf f).hom = equalizer.ι f f :=
rfl
#align category_theory.limits.equalizer.iso_source_of_self_hom CategoryTheory.Limits.equalizer.isoSourceOfSelf_hom
@[simp]
theorem equalizer.isoSourceOfSelf_inv :
(equalizer.isoSourceOfSelf f).inv = equalizer.lift (𝟙 X) (by simp) := by
ext
simp [equalizer.isoSourceOfSelf]
#align category_theory.limits.equalizer.iso_source_of_self_inv CategoryTheory.Limits.equalizer.isoSourceOfSelf_inv
section
abbrev HasCoequalizer :=
HasColimit (parallelPair f g)
#align category_theory.limits.has_coequalizer CategoryTheory.Limits.HasCoequalizer
variable [HasCoequalizer f g]
noncomputable abbrev coequalizer : C :=
colimit (parallelPair f g)
#align category_theory.limits.coequalizer CategoryTheory.Limits.coequalizer
noncomputable abbrev coequalizer.π : Y ⟶ coequalizer f g :=
colimit.ι (parallelPair f g) one
#align category_theory.limits.coequalizer.π CategoryTheory.Limits.coequalizer.π
noncomputable abbrev coequalizer.cofork : Cofork f g :=
colimit.cocone (parallelPair f g)
#align category_theory.limits.coequalizer.cofork CategoryTheory.Limits.coequalizer.cofork
@[simp]
theorem coequalizer.cofork_π : (coequalizer.cofork f g).π = coequalizer.π f g :=
rfl
#align category_theory.limits.coequalizer.cofork_π CategoryTheory.Limits.coequalizer.cofork_π
-- Porting note (#10618): simp can prove this, simp removed
theorem coequalizer.cofork_ι_app_one : (coequalizer.cofork f g).ι.app one = coequalizer.π f g :=
rfl
#align category_theory.limits.coequalizer.cofork_ι_app_one CategoryTheory.Limits.coequalizer.cofork_ι_app_one
@[reassoc]
theorem coequalizer.condition : f ≫ coequalizer.π f g = g ≫ coequalizer.π f g :=
Cofork.condition <| colimit.cocone <| parallelPair f g
#align category_theory.limits.coequalizer.condition CategoryTheory.Limits.coequalizer.condition
noncomputable def coequalizerIsCoequalizer :
IsColimit (Cofork.ofπ (coequalizer.π f g) (coequalizer.condition f g)) :=
IsColimit.ofIsoColimit (colimit.isColimit _) (Cofork.ext (Iso.refl _) (by aesop))
#align category_theory.limits.coequalizer_is_coequalizer CategoryTheory.Limits.coequalizerIsCoequalizer
variable {f g}
noncomputable abbrev coequalizer.desc {W : C} (k : Y ⟶ W) (h : f ≫ k = g ≫ k) :
coequalizer f g ⟶ W :=
colimit.desc (parallelPair f g) (Cofork.ofπ k h)
#align category_theory.limits.coequalizer.desc CategoryTheory.Limits.coequalizer.desc
-- Porting note (#10618): removing simp since simp can prove this and reassoc version
@[reassoc]
theorem coequalizer.π_desc {W : C} (k : Y ⟶ W) (h : f ≫ k = g ≫ k) :
coequalizer.π f g ≫ coequalizer.desc k h = k :=
colimit.ι_desc _ _
#align category_theory.limits.coequalizer.π_desc CategoryTheory.Limits.coequalizer.π_desc
theorem coequalizer.π_colimMap_desc {X' Y' Z : C} (f' g' : X' ⟶ Y') [HasCoequalizer f' g']
(p : X ⟶ X') (q : Y ⟶ Y') (wf : f ≫ q = p ≫ f') (wg : g ≫ q = p ≫ g') (h : Y' ⟶ Z)
(wh : f' ≫ h = g' ≫ h) :
coequalizer.π f g ≫ colimMap (parallelPairHom f g f' g' p q wf wg) ≫ coequalizer.desc h wh =
q ≫ h := by
rw [ι_colimMap_assoc, parallelPairHom_app_one, coequalizer.π_desc]
#align category_theory.limits.coequalizer.π_colim_map_desc CategoryTheory.Limits.coequalizer.π_colimMap_desc
noncomputable def coequalizer.desc' {W : C} (k : Y ⟶ W) (h : f ≫ k = g ≫ k) :
{ l : coequalizer f g ⟶ W // coequalizer.π f g ≫ l = k } :=
⟨coequalizer.desc k h, coequalizer.π_desc _ _⟩
#align category_theory.limits.coequalizer.desc' CategoryTheory.Limits.coequalizer.desc'
@[ext]
theorem coequalizer.hom_ext {W : C} {k l : coequalizer f g ⟶ W}
(h : coequalizer.π f g ≫ k = coequalizer.π f g ≫ l) : k = l :=
Cofork.IsColimit.hom_ext (colimit.isColimit _) h
#align category_theory.limits.coequalizer.hom_ext CategoryTheory.Limits.coequalizer.hom_ext
theorem coequalizer.existsUnique {W : C} (k : Y ⟶ W) (h : f ≫ k = g ≫ k) :
∃! d : coequalizer f g ⟶ W, coequalizer.π f g ≫ d = k :=
Cofork.IsColimit.existsUnique (colimit.isColimit _) _ h
#align category_theory.limits.coequalizer.exists_unique CategoryTheory.Limits.coequalizer.existsUnique
instance coequalizer.π_epi : Epi (coequalizer.π f g) where
left_cancellation _ _ w := coequalizer.hom_ext w
#align category_theory.limits.coequalizer.π_epi CategoryTheory.Limits.coequalizer.π_epi
end
section
variable {f g}
theorem epi_of_isColimit_cofork {c : Cofork f g} (i : IsColimit c) : Epi c.π :=
{ left_cancellation := fun _ _ w => Cofork.IsColimit.hom_ext i w }
#align category_theory.limits.epi_of_is_colimit_cofork CategoryTheory.Limits.epi_of_isColimit_cofork
end
section
variable {f g}
def idCofork (h : f = g) : Cofork f g :=
Cofork.ofπ (𝟙 Y) <| h ▸ rfl
#align category_theory.limits.id_cofork CategoryTheory.Limits.idCofork
def isColimitIdCofork (h : f = g) : IsColimit (idCofork h) :=
Cofork.IsColimit.mk _ (fun s => Cofork.π s) (fun s => Category.id_comp _) fun s m h => by
convert h
exact (Category.id_comp _).symm
#align category_theory.limits.is_colimit_id_cofork CategoryTheory.Limits.isColimitIdCofork
theorem isIso_colimit_cocone_parallelPair_of_eq (h₀ : f = g) {c : Cofork f g} (h : IsColimit c) :
IsIso c.π :=
Iso.isIso_hom <| IsColimit.coconePointUniqueUpToIso (isColimitIdCofork h₀) h
#align category_theory.limits.is_iso_colimit_cocone_parallel_pair_of_eq CategoryTheory.Limits.isIso_colimit_cocone_parallelPair_of_eq
theorem coequalizer.π_of_eq [HasCoequalizer f g] (h : f = g) : IsIso (coequalizer.π f g) :=
isIso_colimit_cocone_parallelPair_of_eq h <| colimit.isColimit _
#align category_theory.limits.coequalizer.π_of_eq CategoryTheory.Limits.coequalizer.π_of_eq
theorem isIso_colimit_cocone_parallelPair_of_self {c : Cofork f f} (h : IsColimit c) : IsIso c.π :=
isIso_colimit_cocone_parallelPair_of_eq rfl h
#align category_theory.limits.is_iso_colimit_cocone_parallel_pair_of_self CategoryTheory.Limits.isIso_colimit_cocone_parallelPair_of_self
theorem isIso_limit_cocone_parallelPair_of_epi {c : Cofork f g} (h : IsColimit c) [Mono c.π] :
IsIso c.π :=
isIso_colimit_cocone_parallelPair_of_eq ((cancel_mono _).1 (Cofork.condition c)) h
#align category_theory.limits.is_iso_limit_cocone_parallel_pair_of_epi CategoryTheory.Limits.isIso_limit_cocone_parallelPair_of_epi
theorem eq_of_mono_cofork_π (t : Cofork f g) [Mono (Cofork.π t)] : f = g :=
(cancel_mono (Cofork.π t)).1 <| Cofork.condition t
#align category_theory.limits.eq_of_mono_cofork_π CategoryTheory.Limits.eq_of_mono_cofork_π
theorem eq_of_mono_coequalizer [HasCoequalizer f g] [Mono (coequalizer.π f g)] : f = g :=
(cancel_mono (coequalizer.π f g)).1 <| coequalizer.condition _ _
#align category_theory.limits.eq_of_mono_coequalizer CategoryTheory.Limits.eq_of_mono_coequalizer
end
instance hasCoequalizer_of_self : HasCoequalizer f f :=
HasColimit.mk
{ cocone := idCofork rfl
isColimit := isColimitIdCofork rfl }
#align category_theory.limits.has_coequalizer_of_self CategoryTheory.Limits.hasCoequalizer_of_self
instance coequalizer.π_of_self : IsIso (coequalizer.π f f) :=
coequalizer.π_of_eq rfl
#align category_theory.limits.coequalizer.π_of_self CategoryTheory.Limits.coequalizer.π_of_self
noncomputable def coequalizer.isoTargetOfSelf : coequalizer f f ≅ Y :=
(asIso (coequalizer.π f f)).symm
#align category_theory.limits.coequalizer.iso_target_of_self CategoryTheory.Limits.coequalizer.isoTargetOfSelf
@[simp]
theorem coequalizer.isoTargetOfSelf_hom :
(coequalizer.isoTargetOfSelf f).hom = coequalizer.desc (𝟙 Y) (by simp) := by
ext
simp [coequalizer.isoTargetOfSelf]
#align category_theory.limits.coequalizer.iso_target_of_self_hom CategoryTheory.Limits.coequalizer.isoTargetOfSelf_hom
@[simp]
theorem coequalizer.isoTargetOfSelf_inv : (coequalizer.isoTargetOfSelf f).inv = coequalizer.π f f :=
rfl
#align category_theory.limits.coequalizer.iso_target_of_self_inv CategoryTheory.Limits.coequalizer.isoTargetOfSelf_inv
section Comparison
variable {D : Type u₂} [Category.{v₂} D] (G : C ⥤ D)
noncomputable def equalizerComparison [HasEqualizer f g] [HasEqualizer (G.map f) (G.map g)] :
G.obj (equalizer f g) ⟶ equalizer (G.map f) (G.map g) :=
equalizer.lift (G.map (equalizer.ι _ _))
(by simp only [← G.map_comp]; rw [equalizer.condition])
#align category_theory.limits.equalizer_comparison CategoryTheory.Limits.equalizerComparison
@[reassoc (attr := simp)]
theorem equalizerComparison_comp_π [HasEqualizer f g] [HasEqualizer (G.map f) (G.map g)] :
equalizerComparison f g G ≫ equalizer.ι (G.map f) (G.map g) = G.map (equalizer.ι f g) :=
equalizer.lift_ι _ _
#align category_theory.limits.equalizer_comparison_comp_π CategoryTheory.Limits.equalizerComparison_comp_π
@[reassoc (attr := simp)]
theorem map_lift_equalizerComparison [HasEqualizer f g] [HasEqualizer (G.map f) (G.map g)] {Z : C}
{h : Z ⟶ X} (w : h ≫ f = h ≫ g) :
G.map (equalizer.lift h w) ≫ equalizerComparison f g G =
equalizer.lift (G.map h) (by simp only [← G.map_comp, w]) := by
apply equalizer.hom_ext
simp [← G.map_comp]
#align category_theory.limits.map_lift_equalizer_comparison CategoryTheory.Limits.map_lift_equalizerComparison
noncomputable def coequalizerComparison [HasCoequalizer f g] [HasCoequalizer (G.map f) (G.map g)] :
coequalizer (G.map f) (G.map g) ⟶ G.obj (coequalizer f g) :=
coequalizer.desc (G.map (coequalizer.π _ _))
(by simp only [← G.map_comp]; rw [coequalizer.condition])
#align category_theory.limits.coequalizer_comparison CategoryTheory.Limits.coequalizerComparison
@[reassoc (attr := simp)]
theorem ι_comp_coequalizerComparison [HasCoequalizer f g] [HasCoequalizer (G.map f) (G.map g)] :
coequalizer.π _ _ ≫ coequalizerComparison f g G = G.map (coequalizer.π _ _) :=
coequalizer.π_desc _ _
#align category_theory.limits.ι_comp_coequalizer_comparison CategoryTheory.Limits.ι_comp_coequalizerComparison
@[reassoc (attr := simp)]
| Mathlib/CategoryTheory/Limits/Shapes/Equalizers.lean | 1,168 | 1,173 | theorem coequalizerComparison_map_desc [HasCoequalizer f g] [HasCoequalizer (G.map f) (G.map g)]
{Z : C} {h : Y ⟶ Z} (w : f ≫ h = g ≫ h) :
coequalizerComparison f g G ≫ G.map (coequalizer.desc h w) =
coequalizer.desc (G.map h) (by simp only [← G.map_comp, w]) := by |
apply coequalizer.hom_ext
simp [← G.map_comp]
|
import Mathlib.SetTheory.Cardinal.Ordinal
#align_import set_theory.cardinal.continuum from "leanprover-community/mathlib"@"e08a42b2dd544cf11eba72e5fc7bf199d4349925"
namespace Cardinal
universe u v
open Cardinal
def continuum : Cardinal.{u} :=
2 ^ ℵ₀
#align cardinal.continuum Cardinal.continuum
scoped notation "𝔠" => Cardinal.continuum
@[simp]
theorem two_power_aleph0 : 2 ^ aleph0.{u} = continuum.{u} :=
rfl
#align cardinal.two_power_aleph_0 Cardinal.two_power_aleph0
@[simp]
theorem lift_continuum : lift.{v} 𝔠 = 𝔠 := by
rw [← two_power_aleph0, lift_two_power, lift_aleph0, two_power_aleph0]
#align cardinal.lift_continuum Cardinal.lift_continuum
@[simp]
theorem continuum_le_lift {c : Cardinal.{u}} : 𝔠 ≤ lift.{v} c ↔ 𝔠 ≤ c := by
-- Porting note: added explicit universes
rw [← lift_continuum.{u,v}, lift_le]
#align cardinal.continuum_le_lift Cardinal.continuum_le_lift
@[simp]
theorem lift_le_continuum {c : Cardinal.{u}} : lift.{v} c ≤ 𝔠 ↔ c ≤ 𝔠 := by
-- Porting note: added explicit universes
rw [← lift_continuum.{u,v}, lift_le]
#align cardinal.lift_le_continuum Cardinal.lift_le_continuum
@[simp]
theorem continuum_lt_lift {c : Cardinal.{u}} : 𝔠 < lift.{v} c ↔ 𝔠 < c := by
-- Porting note: added explicit universes
rw [← lift_continuum.{u,v}, lift_lt]
#align cardinal.continuum_lt_lift Cardinal.continuum_lt_lift
@[simp]
theorem lift_lt_continuum {c : Cardinal.{u}} : lift.{v} c < 𝔠 ↔ c < 𝔠 := by
-- Porting note: added explicit universes
rw [← lift_continuum.{u,v}, lift_lt]
#align cardinal.lift_lt_continuum Cardinal.lift_lt_continuum
theorem aleph0_lt_continuum : ℵ₀ < 𝔠 :=
cantor ℵ₀
#align cardinal.aleph_0_lt_continuum Cardinal.aleph0_lt_continuum
theorem aleph0_le_continuum : ℵ₀ ≤ 𝔠 :=
aleph0_lt_continuum.le
#align cardinal.aleph_0_le_continuum Cardinal.aleph0_le_continuum
@[simp]
theorem beth_one : beth 1 = 𝔠 := by simpa using beth_succ 0
#align cardinal.beth_one Cardinal.beth_one
theorem nat_lt_continuum (n : ℕ) : ↑n < 𝔠 :=
(nat_lt_aleph0 n).trans aleph0_lt_continuum
#align cardinal.nat_lt_continuum Cardinal.nat_lt_continuum
| Mathlib/SetTheory/Cardinal/Continuum.lean | 90 | 90 | theorem mk_set_nat : #(Set ℕ) = 𝔠 := by | simp
|
import Mathlib.Topology.Order.ProjIcc
import Mathlib.Topology.CompactOpen
import Mathlib.Topology.UnitInterval
#align_import topology.path_connected from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982"
noncomputable section
open scoped Classical
open Topology Filter unitInterval Set Function
variable {X Y : Type*} [TopologicalSpace X] [TopologicalSpace Y] {x y z : X} {ι : Type*}
-- porting note (#5171): removed @[nolint has_nonempty_instance]
structure Path (x y : X) extends C(I, X) where
source' : toFun 0 = x
target' : toFun 1 = y
#align path Path
instance Path.funLike : FunLike (Path x y) I X where
coe := fun γ ↦ ⇑γ.toContinuousMap
coe_injective' := fun γ₁ γ₂ h => by
simp only [DFunLike.coe_fn_eq] at h
cases γ₁; cases γ₂; congr
-- Porting note (#10754): added this instance so that we can use `FunLike.coe` for `CoeFun`
-- this also fixed very strange `simp` timeout issues
instance Path.continuousMapClass : ContinuousMapClass (Path x y) I X where
map_continuous := fun γ => show Continuous γ.toContinuousMap by continuity
-- Porting note: not necessary in light of the instance above
@[ext]
protected theorem Path.ext : ∀ {γ₁ γ₂ : Path x y}, (γ₁ : I → X) = γ₂ → γ₁ = γ₂ := by
rintro ⟨⟨x, h11⟩, h12, h13⟩ ⟨⟨x, h21⟩, h22, h23⟩ rfl
rfl
#align path.ext Path.ext
namespace Path
@[simp]
theorem coe_mk_mk (f : I → X) (h₁) (h₂ : f 0 = x) (h₃ : f 1 = y) :
⇑(mk ⟨f, h₁⟩ h₂ h₃ : Path x y) = f :=
rfl
#align path.coe_mk Path.coe_mk_mk
-- Porting note: the name `Path.coe_mk` better refers to a new lemma below
variable (γ : Path x y)
@[continuity]
protected theorem continuous : Continuous γ :=
γ.continuous_toFun
#align path.continuous Path.continuous
@[simp]
protected theorem source : γ 0 = x :=
γ.source'
#align path.source Path.source
@[simp]
protected theorem target : γ 1 = y :=
γ.target'
#align path.target Path.target
def simps.apply : I → X :=
γ
#align path.simps.apply Path.simps.apply
initialize_simps_projections Path (toFun → simps.apply, -toContinuousMap)
@[simp]
theorem coe_toContinuousMap : ⇑γ.toContinuousMap = γ :=
rfl
#align path.coe_to_continuous_map Path.coe_toContinuousMap
-- Porting note: this is needed because of the `Path.continuousMapClass` instance
@[simp]
theorem coe_mk : ⇑(γ : C(I, X)) = γ :=
rfl
instance hasUncurryPath {X α : Type*} [TopologicalSpace X] {x y : α → X} :
HasUncurry (∀ a : α, Path (x a) (y a)) (α × I) X :=
⟨fun φ p => φ p.1 p.2⟩
#align path.has_uncurry_path Path.hasUncurryPath
@[refl, simps]
def refl (x : X) : Path x x where
toFun _t := x
continuous_toFun := continuous_const
source' := rfl
target' := rfl
#align path.refl Path.refl
@[simp]
theorem refl_range {a : X} : range (Path.refl a) = {a} := by simp [Path.refl, CoeFun.coe]
#align path.refl_range Path.refl_range
@[symm, simps]
def symm (γ : Path x y) : Path y x where
toFun := γ ∘ σ
continuous_toFun := by continuity
source' := by simpa [-Path.target] using γ.target
target' := by simpa [-Path.source] using γ.source
#align path.symm Path.symm
@[simp]
theorem symm_symm (γ : Path x y) : γ.symm.symm = γ := by
ext t
show γ (σ (σ t)) = γ t
rw [unitInterval.symm_symm]
#align path.symm_symm Path.symm_symm
theorem symm_bijective : Function.Bijective (Path.symm : Path x y → Path y x) :=
Function.bijective_iff_has_inverse.mpr ⟨_, symm_symm, symm_symm⟩
@[simp]
theorem refl_symm {a : X} : (Path.refl a).symm = Path.refl a := by
ext
rfl
#align path.refl_symm Path.refl_symm
@[simp]
theorem symm_range {a b : X} (γ : Path a b) : range γ.symm = range γ := by
ext x
simp only [mem_range, Path.symm, DFunLike.coe, unitInterval.symm, SetCoe.exists, comp_apply,
Subtype.coe_mk]
constructor <;> rintro ⟨y, hy, hxy⟩ <;> refine ⟨1 - y, mem_iff_one_sub_mem.mp hy, ?_⟩ <;>
convert hxy
simp
#align path.symm_range Path.symm_range
open ContinuousMap
instance topologicalSpace : TopologicalSpace (Path x y) :=
TopologicalSpace.induced ((↑) : _ → C(I, X)) ContinuousMap.compactOpen
theorem continuous_eval : Continuous fun p : Path x y × I => p.1 p.2 :=
continuous_eval.comp <| (continuous_induced_dom (α := Path x y)).prod_map continuous_id
#align path.continuous_eval Path.continuous_eval
@[continuity]
theorem _root_.Continuous.path_eval {Y} [TopologicalSpace Y] {f : Y → Path x y} {g : Y → I}
(hf : Continuous f) (hg : Continuous g) : Continuous fun y => f y (g y) :=
Continuous.comp continuous_eval (hf.prod_mk hg)
#align continuous.path_eval Continuous.path_eval
theorem continuous_uncurry_iff {Y} [TopologicalSpace Y] {g : Y → Path x y} :
Continuous ↿g ↔ Continuous g :=
Iff.symm <| continuous_induced_rng.trans
⟨fun h => continuous_uncurry_of_continuous ⟨_, h⟩,
continuous_of_continuous_uncurry (fun (y : Y) ↦ ContinuousMap.mk (g y))⟩
#align path.continuous_uncurry_iff Path.continuous_uncurry_iff
def extend : ℝ → X :=
IccExtend zero_le_one γ
#align path.extend Path.extend
theorem _root_.Continuous.path_extend {γ : Y → Path x y} {f : Y → ℝ} (hγ : Continuous ↿γ)
(hf : Continuous f) : Continuous fun t => (γ t).extend (f t) :=
Continuous.IccExtend hγ hf
#align continuous.path_extend Continuous.path_extend
@[continuity]
theorem continuous_extend : Continuous γ.extend :=
γ.continuous.Icc_extend'
#align path.continuous_extend Path.continuous_extend
theorem _root_.Filter.Tendsto.path_extend
{l r : Y → X} {y : Y} {l₁ : Filter ℝ} {l₂ : Filter X} {γ : ∀ y, Path (l y) (r y)}
(hγ : Tendsto (↿γ) (𝓝 y ×ˢ l₁.map (projIcc 0 1 zero_le_one)) l₂) :
Tendsto (↿fun x => (γ x).extend) (𝓝 y ×ˢ l₁) l₂ :=
Filter.Tendsto.IccExtend _ hγ
#align filter.tendsto.path_extend Filter.Tendsto.path_extend
theorem _root_.ContinuousAt.path_extend {g : Y → ℝ} {l r : Y → X} (γ : ∀ y, Path (l y) (r y))
{y : Y} (hγ : ContinuousAt (↿γ) (y, projIcc 0 1 zero_le_one (g y))) (hg : ContinuousAt g y) :
ContinuousAt (fun i => (γ i).extend (g i)) y :=
hγ.IccExtend (fun x => γ x) hg
#align continuous_at.path_extend ContinuousAt.path_extend
@[simp]
theorem extend_extends {a b : X} (γ : Path a b) {t : ℝ}
(ht : t ∈ (Icc 0 1 : Set ℝ)) : γ.extend t = γ ⟨t, ht⟩ :=
IccExtend_of_mem _ γ ht
#align path.extend_extends Path.extend_extends
theorem extend_zero : γ.extend 0 = x := by simp
#align path.extend_zero Path.extend_zero
theorem extend_one : γ.extend 1 = y := by simp
#align path.extend_one Path.extend_one
@[simp]
theorem extend_extends' {a b : X} (γ : Path a b) (t : (Icc 0 1 : Set ℝ)) : γ.extend t = γ t :=
IccExtend_val _ γ t
#align path.extend_extends' Path.extend_extends'
@[simp]
theorem extend_range {a b : X} (γ : Path a b) :
range γ.extend = range γ :=
IccExtend_range _ γ
#align path.extend_range Path.extend_range
theorem extend_of_le_zero {a b : X} (γ : Path a b) {t : ℝ}
(ht : t ≤ 0) : γ.extend t = a :=
(IccExtend_of_le_left _ _ ht).trans γ.source
#align path.extend_of_le_zero Path.extend_of_le_zero
theorem extend_of_one_le {a b : X} (γ : Path a b) {t : ℝ}
(ht : 1 ≤ t) : γ.extend t = b :=
(IccExtend_of_right_le _ _ ht).trans γ.target
#align path.extend_of_one_le Path.extend_of_one_le
@[simp]
theorem refl_extend {a : X} : (Path.refl a).extend = fun _ => a :=
rfl
#align path.refl_extend Path.refl_extend
def ofLine {f : ℝ → X} (hf : ContinuousOn f I) (h₀ : f 0 = x) (h₁ : f 1 = y) : Path x y where
toFun := f ∘ ((↑) : unitInterval → ℝ)
continuous_toFun := hf.comp_continuous continuous_subtype_val Subtype.prop
source' := h₀
target' := h₁
#align path.of_line Path.ofLine
theorem ofLine_mem {f : ℝ → X} (hf : ContinuousOn f I) (h₀ : f 0 = x) (h₁ : f 1 = y) :
∀ t, ofLine hf h₀ h₁ t ∈ f '' I := fun ⟨t, t_in⟩ => ⟨t, t_in, rfl⟩
#align path.of_line_mem Path.ofLine_mem
attribute [local simp] Iic_def
set_option tactic.skipAssignedInstances false in
@[trans]
def trans (γ : Path x y) (γ' : Path y z) : Path x z where
toFun := (fun t : ℝ => if t ≤ 1 / 2 then γ.extend (2 * t) else γ'.extend (2 * t - 1)) ∘ (↑)
continuous_toFun := by
refine
(Continuous.if_le ?_ ?_ continuous_id continuous_const (by norm_num)).comp
continuous_subtype_val <;>
continuity
source' := by norm_num
target' := by norm_num
#align path.trans Path.trans
theorem trans_apply (γ : Path x y) (γ' : Path y z) (t : I) :
(γ.trans γ') t =
if h : (t : ℝ) ≤ 1 / 2 then γ ⟨2 * t, (mul_pos_mem_iff zero_lt_two).2 ⟨t.2.1, h⟩⟩
else γ' ⟨2 * t - 1, two_mul_sub_one_mem_iff.2 ⟨(not_le.1 h).le, t.2.2⟩⟩ :=
show ite _ _ _ = _ by split_ifs <;> rw [extend_extends]
#align path.trans_apply Path.trans_apply
@[simp]
theorem trans_symm (γ : Path x y) (γ' : Path y z) : (γ.trans γ').symm = γ'.symm.trans γ.symm := by
ext t
simp only [trans_apply, ← one_div, symm_apply, not_le, Function.comp_apply]
split_ifs with h h₁ h₂ <;> rw [coe_symm_eq] at h
· have ht : (t : ℝ) = 1 / 2 := by linarith
norm_num [ht]
· refine congr_arg _ (Subtype.ext ?_)
norm_num [sub_sub_eq_add_sub, mul_sub]
· refine congr_arg _ (Subtype.ext ?_)
norm_num [mul_sub, h]
ring -- TODO norm_num should really do this
· exfalso
linarith
#align path.trans_symm Path.trans_symm
@[simp]
theorem refl_trans_refl {a : X} :
(Path.refl a).trans (Path.refl a) = Path.refl a := by
ext
simp only [Path.trans, ite_self, one_div, Path.refl_extend]
rfl
#align path.refl_trans_refl Path.refl_trans_refl
theorem trans_range {a b c : X} (γ₁ : Path a b) (γ₂ : Path b c) :
range (γ₁.trans γ₂) = range γ₁ ∪ range γ₂ := by
rw [Path.trans]
apply eq_of_subset_of_subset
· rintro x ⟨⟨t, ht0, ht1⟩, hxt⟩
by_cases h : t ≤ 1 / 2
· left
use ⟨2 * t, ⟨by linarith, by linarith⟩⟩
rw [← γ₁.extend_extends]
rwa [coe_mk_mk, Function.comp_apply, if_pos h] at hxt
· right
use ⟨2 * t - 1, ⟨by linarith, by linarith⟩⟩
rw [← γ₂.extend_extends]
rwa [coe_mk_mk, Function.comp_apply, if_neg h] at hxt
· rintro x (⟨⟨t, ht0, ht1⟩, hxt⟩ | ⟨⟨t, ht0, ht1⟩, hxt⟩)
· use ⟨t / 2, ⟨by linarith, by linarith⟩⟩
have : t / 2 ≤ 1 / 2 := (div_le_div_right (zero_lt_two : (0 : ℝ) < 2)).mpr ht1
rw [coe_mk_mk, Function.comp_apply, if_pos this, Subtype.coe_mk]
ring_nf
rwa [γ₁.extend_extends]
· by_cases h : t = 0
· use ⟨1 / 2, ⟨by linarith, by linarith⟩⟩
rw [coe_mk_mk, Function.comp_apply, if_pos le_rfl, Subtype.coe_mk,
mul_one_div_cancel (two_ne_zero' ℝ)]
rw [γ₁.extend_one]
rwa [← γ₂.extend_extends, h, γ₂.extend_zero] at hxt
· use ⟨(t + 1) / 2, ⟨by linarith, by linarith⟩⟩
replace h : t ≠ 0 := h
have ht0 := lt_of_le_of_ne ht0 h.symm
have : ¬(t + 1) / 2 ≤ 1 / 2 := by
rw [not_le]
linarith
rw [coe_mk_mk, Function.comp_apply, Subtype.coe_mk, if_neg this]
ring_nf
rwa [γ₂.extend_extends]
#align path.trans_range Path.trans_range
def map' (γ : Path x y) {f : X → Y} (h : ContinuousOn f (range γ)) : Path (f x) (f y) where
toFun := f ∘ γ
continuous_toFun := h.comp_continuous γ.continuous (fun x ↦ mem_range_self x)
source' := by simp
target' := by simp
def map (γ : Path x y) {f : X → Y} (h : Continuous f) :
Path (f x) (f y) := γ.map' h.continuousOn
#align path.map Path.map
@[simp]
| Mathlib/Topology/Connected/PathConnected.lean | 415 | 418 | theorem map_coe (γ : Path x y) {f : X → Y} (h : Continuous f) :
(γ.map h : I → Y) = f ∘ γ := by |
ext t
rfl
|
import Mathlib.MeasureTheory.Function.SimpleFuncDenseLp
#align_import measure_theory.integral.set_to_l1 from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982"
noncomputable section
open scoped Classical Topology NNReal ENNReal MeasureTheory Pointwise
open Set Filter TopologicalSpace ENNReal EMetric
namespace MeasureTheory
variable {α E F F' G 𝕜 : Type*} {p : ℝ≥0∞} [NormedAddCommGroup E] [NormedSpace ℝ E]
[NormedAddCommGroup F] [NormedSpace ℝ F] [NormedAddCommGroup F'] [NormedSpace ℝ F']
[NormedAddCommGroup G] {m : MeasurableSpace α} {μ : Measure α}
local infixr:25 " →ₛ " => SimpleFunc
open Finset
section FinMeasAdditive
def FinMeasAdditive {β} [AddMonoid β] {_ : MeasurableSpace α} (μ : Measure α) (T : Set α → β) :
Prop :=
∀ s t, MeasurableSet s → MeasurableSet t → μ s ≠ ∞ → μ t ≠ ∞ → s ∩ t = ∅ → T (s ∪ t) = T s + T t
#align measure_theory.fin_meas_additive MeasureTheory.FinMeasAdditive
namespace FinMeasAdditive
variable {β : Type*} [AddCommMonoid β] {T T' : Set α → β}
theorem zero : FinMeasAdditive μ (0 : Set α → β) := fun s t _ _ _ _ _ => by simp
#align measure_theory.fin_meas_additive.zero MeasureTheory.FinMeasAdditive.zero
theorem add (hT : FinMeasAdditive μ T) (hT' : FinMeasAdditive μ T') :
FinMeasAdditive μ (T + T') := by
intro s t hs ht hμs hμt hst
simp only [hT s t hs ht hμs hμt hst, hT' s t hs ht hμs hμt hst, Pi.add_apply]
abel
#align measure_theory.fin_meas_additive.add MeasureTheory.FinMeasAdditive.add
theorem smul [Monoid 𝕜] [DistribMulAction 𝕜 β] (hT : FinMeasAdditive μ T) (c : 𝕜) :
FinMeasAdditive μ fun s => c • T s := fun s t hs ht hμs hμt hst => by
simp [hT s t hs ht hμs hμt hst]
#align measure_theory.fin_meas_additive.smul MeasureTheory.FinMeasAdditive.smul
theorem of_eq_top_imp_eq_top {μ' : Measure α} (h : ∀ s, MeasurableSet s → μ s = ∞ → μ' s = ∞)
(hT : FinMeasAdditive μ T) : FinMeasAdditive μ' T := fun s t hs ht hμ's hμ't hst =>
hT s t hs ht (mt (h s hs) hμ's) (mt (h t ht) hμ't) hst
#align measure_theory.fin_meas_additive.of_eq_top_imp_eq_top MeasureTheory.FinMeasAdditive.of_eq_top_imp_eq_top
| Mathlib/MeasureTheory/Integral/SetToL1.lean | 122 | 127 | theorem of_smul_measure (c : ℝ≥0∞) (hc_ne_top : c ≠ ∞) (hT : FinMeasAdditive (c • μ) T) :
FinMeasAdditive μ T := by |
refine of_eq_top_imp_eq_top (fun s _ hμs => ?_) hT
rw [Measure.smul_apply, smul_eq_mul, ENNReal.mul_eq_top] at hμs
simp only [hc_ne_top, or_false_iff, Ne, false_and_iff] at hμs
exact hμs.2
|
import Mathlib.Analysis.Asymptotics.AsymptoticEquivalent
import Mathlib.Analysis.Calculus.FDeriv.Linear
import Mathlib.Analysis.Calculus.FDeriv.Comp
#align_import analysis.calculus.fderiv.equiv from "leanprover-community/mathlib"@"e3fb84046afd187b710170887195d50bada934ee"
open Filter Asymptotics ContinuousLinearMap Set Metric
open scoped Classical
open Topology NNReal Filter Asymptotics ENNReal
noncomputable section
section
variable {𝕜 : Type*} [NontriviallyNormedField 𝕜]
variable {E : Type*} [NormedAddCommGroup E] [NormedSpace 𝕜 E]
variable {F : Type*} [NormedAddCommGroup F] [NormedSpace 𝕜 F]
variable {G : Type*} [NormedAddCommGroup G] [NormedSpace 𝕜 G]
variable {G' : Type*} [NormedAddCommGroup G'] [NormedSpace 𝕜 G']
variable {f f₀ f₁ g : E → F}
variable {f' f₀' f₁' g' : E →L[𝕜] F}
variable (e : E →L[𝕜] F)
variable {x : E}
variable {s t : Set E}
variable {L L₁ L₂ : Filter E}
namespace ContinuousLinearEquiv
variable (iso : E ≃L[𝕜] F)
@[fun_prop]
protected theorem hasStrictFDerivAt : HasStrictFDerivAt iso (iso : E →L[𝕜] F) x :=
iso.toContinuousLinearMap.hasStrictFDerivAt
#align continuous_linear_equiv.has_strict_fderiv_at ContinuousLinearEquiv.hasStrictFDerivAt
@[fun_prop]
protected theorem hasFDerivWithinAt : HasFDerivWithinAt iso (iso : E →L[𝕜] F) s x :=
iso.toContinuousLinearMap.hasFDerivWithinAt
#align continuous_linear_equiv.has_fderiv_within_at ContinuousLinearEquiv.hasFDerivWithinAt
@[fun_prop]
protected theorem hasFDerivAt : HasFDerivAt iso (iso : E →L[𝕜] F) x :=
iso.toContinuousLinearMap.hasFDerivAtFilter
#align continuous_linear_equiv.has_fderiv_at ContinuousLinearEquiv.hasFDerivAt
@[fun_prop]
protected theorem differentiableAt : DifferentiableAt 𝕜 iso x :=
iso.hasFDerivAt.differentiableAt
#align continuous_linear_equiv.differentiable_at ContinuousLinearEquiv.differentiableAt
@[fun_prop]
protected theorem differentiableWithinAt : DifferentiableWithinAt 𝕜 iso s x :=
iso.differentiableAt.differentiableWithinAt
#align continuous_linear_equiv.differentiable_within_at ContinuousLinearEquiv.differentiableWithinAt
protected theorem fderiv : fderiv 𝕜 iso x = iso :=
iso.hasFDerivAt.fderiv
#align continuous_linear_equiv.fderiv ContinuousLinearEquiv.fderiv
protected theorem fderivWithin (hxs : UniqueDiffWithinAt 𝕜 s x) : fderivWithin 𝕜 iso s x = iso :=
iso.toContinuousLinearMap.fderivWithin hxs
#align continuous_linear_equiv.fderiv_within ContinuousLinearEquiv.fderivWithin
@[fun_prop]
protected theorem differentiable : Differentiable 𝕜 iso := fun _ => iso.differentiableAt
#align continuous_linear_equiv.differentiable ContinuousLinearEquiv.differentiable
@[fun_prop]
protected theorem differentiableOn : DifferentiableOn 𝕜 iso s :=
iso.differentiable.differentiableOn
#align continuous_linear_equiv.differentiable_on ContinuousLinearEquiv.differentiableOn
theorem comp_differentiableWithinAt_iff {f : G → E} {s : Set G} {x : G} :
DifferentiableWithinAt 𝕜 (iso ∘ f) s x ↔ DifferentiableWithinAt 𝕜 f s x := by
refine
⟨fun H => ?_, fun H => iso.differentiable.differentiableAt.comp_differentiableWithinAt x H⟩
have : DifferentiableWithinAt 𝕜 (iso.symm ∘ iso ∘ f) s x :=
iso.symm.differentiable.differentiableAt.comp_differentiableWithinAt x H
rwa [← Function.comp.assoc iso.symm iso f, iso.symm_comp_self] at this
#align continuous_linear_equiv.comp_differentiable_within_at_iff ContinuousLinearEquiv.comp_differentiableWithinAt_iff
theorem comp_differentiableAt_iff {f : G → E} {x : G} :
DifferentiableAt 𝕜 (iso ∘ f) x ↔ DifferentiableAt 𝕜 f x := by
rw [← differentiableWithinAt_univ, ← differentiableWithinAt_univ,
iso.comp_differentiableWithinAt_iff]
#align continuous_linear_equiv.comp_differentiable_at_iff ContinuousLinearEquiv.comp_differentiableAt_iff
theorem comp_differentiableOn_iff {f : G → E} {s : Set G} :
DifferentiableOn 𝕜 (iso ∘ f) s ↔ DifferentiableOn 𝕜 f s := by
rw [DifferentiableOn, DifferentiableOn]
simp only [iso.comp_differentiableWithinAt_iff]
#align continuous_linear_equiv.comp_differentiable_on_iff ContinuousLinearEquiv.comp_differentiableOn_iff
theorem comp_differentiable_iff {f : G → E} : Differentiable 𝕜 (iso ∘ f) ↔ Differentiable 𝕜 f := by
rw [← differentiableOn_univ, ← differentiableOn_univ]
exact iso.comp_differentiableOn_iff
#align continuous_linear_equiv.comp_differentiable_iff ContinuousLinearEquiv.comp_differentiable_iff
theorem comp_hasFDerivWithinAt_iff {f : G → E} {s : Set G} {x : G} {f' : G →L[𝕜] E} :
HasFDerivWithinAt (iso ∘ f) ((iso : E →L[𝕜] F).comp f') s x ↔ HasFDerivWithinAt f f' s x := by
refine ⟨fun H => ?_, fun H => iso.hasFDerivAt.comp_hasFDerivWithinAt x H⟩
have A : f = iso.symm ∘ iso ∘ f := by
rw [← Function.comp.assoc, iso.symm_comp_self]
rfl
have B : f' = (iso.symm : F →L[𝕜] E).comp ((iso : E →L[𝕜] F).comp f') := by
rw [← ContinuousLinearMap.comp_assoc, iso.coe_symm_comp_coe, ContinuousLinearMap.id_comp]
rw [A, B]
exact iso.symm.hasFDerivAt.comp_hasFDerivWithinAt x H
#align continuous_linear_equiv.comp_has_fderiv_within_at_iff ContinuousLinearEquiv.comp_hasFDerivWithinAt_iff
theorem comp_hasStrictFDerivAt_iff {f : G → E} {x : G} {f' : G →L[𝕜] E} :
HasStrictFDerivAt (iso ∘ f) ((iso : E →L[𝕜] F).comp f') x ↔ HasStrictFDerivAt f f' x := by
refine ⟨fun H => ?_, fun H => iso.hasStrictFDerivAt.comp x H⟩
convert iso.symm.hasStrictFDerivAt.comp x H using 1 <;>
ext z <;> apply (iso.symm_apply_apply _).symm
#align continuous_linear_equiv.comp_has_strict_fderiv_at_iff ContinuousLinearEquiv.comp_hasStrictFDerivAt_iff
theorem comp_hasFDerivAt_iff {f : G → E} {x : G} {f' : G →L[𝕜] E} :
HasFDerivAt (iso ∘ f) ((iso : E →L[𝕜] F).comp f') x ↔ HasFDerivAt f f' x := by
simp_rw [← hasFDerivWithinAt_univ, iso.comp_hasFDerivWithinAt_iff]
#align continuous_linear_equiv.comp_has_fderiv_at_iff ContinuousLinearEquiv.comp_hasFDerivAt_iff
theorem comp_hasFDerivWithinAt_iff' {f : G → E} {s : Set G} {x : G} {f' : G →L[𝕜] F} :
HasFDerivWithinAt (iso ∘ f) f' s x ↔
HasFDerivWithinAt f ((iso.symm : F →L[𝕜] E).comp f') s x := by
rw [← iso.comp_hasFDerivWithinAt_iff, ← ContinuousLinearMap.comp_assoc, iso.coe_comp_coe_symm,
ContinuousLinearMap.id_comp]
#align continuous_linear_equiv.comp_has_fderiv_within_at_iff' ContinuousLinearEquiv.comp_hasFDerivWithinAt_iff'
theorem comp_hasFDerivAt_iff' {f : G → E} {x : G} {f' : G →L[𝕜] F} :
HasFDerivAt (iso ∘ f) f' x ↔ HasFDerivAt f ((iso.symm : F →L[𝕜] E).comp f') x := by
simp_rw [← hasFDerivWithinAt_univ, iso.comp_hasFDerivWithinAt_iff']
#align continuous_linear_equiv.comp_has_fderiv_at_iff' ContinuousLinearEquiv.comp_hasFDerivAt_iff'
theorem comp_fderivWithin {f : G → E} {s : Set G} {x : G} (hxs : UniqueDiffWithinAt 𝕜 s x) :
fderivWithin 𝕜 (iso ∘ f) s x = (iso : E →L[𝕜] F).comp (fderivWithin 𝕜 f s x) := by
by_cases h : DifferentiableWithinAt 𝕜 f s x
· rw [fderiv.comp_fderivWithin x iso.differentiableAt h hxs, iso.fderiv]
· have : ¬DifferentiableWithinAt 𝕜 (iso ∘ f) s x := mt iso.comp_differentiableWithinAt_iff.1 h
rw [fderivWithin_zero_of_not_differentiableWithinAt h,
fderivWithin_zero_of_not_differentiableWithinAt this, ContinuousLinearMap.comp_zero]
#align continuous_linear_equiv.comp_fderiv_within ContinuousLinearEquiv.comp_fderivWithin
theorem comp_fderiv {f : G → E} {x : G} :
fderiv 𝕜 (iso ∘ f) x = (iso : E →L[𝕜] F).comp (fderiv 𝕜 f x) := by
rw [← fderivWithin_univ, ← fderivWithin_univ]
exact iso.comp_fderivWithin uniqueDiffWithinAt_univ
#align continuous_linear_equiv.comp_fderiv ContinuousLinearEquiv.comp_fderiv
lemma _root_.fderivWithin_continuousLinearEquiv_comp (L : G ≃L[𝕜] G') (f : E → (F →L[𝕜] G))
(hs : UniqueDiffWithinAt 𝕜 s x) :
fderivWithin 𝕜 (fun x ↦ (L : G →L[𝕜] G').comp (f x)) s x =
(((ContinuousLinearEquiv.refl 𝕜 F).arrowCongr L)) ∘L (fderivWithin 𝕜 f s x) := by
change fderivWithin 𝕜 (((ContinuousLinearEquiv.refl 𝕜 F).arrowCongr L) ∘ f) s x = _
rw [ContinuousLinearEquiv.comp_fderivWithin _ hs]
lemma _root_.fderiv_continuousLinearEquiv_comp (L : G ≃L[𝕜] G') (f : E → (F →L[𝕜] G)) (x : E) :
fderiv 𝕜 (fun x ↦ (L : G →L[𝕜] G').comp (f x)) x =
(((ContinuousLinearEquiv.refl 𝕜 F).arrowCongr L)) ∘L (fderiv 𝕜 f x) := by
change fderiv 𝕜 (((ContinuousLinearEquiv.refl 𝕜 F).arrowCongr L) ∘ f) x = _
rw [ContinuousLinearEquiv.comp_fderiv]
lemma _root_.fderiv_continuousLinearEquiv_comp' (L : G ≃L[𝕜] G') (f : E → (F →L[𝕜] G)) :
fderiv 𝕜 (fun x ↦ (L : G →L[𝕜] G').comp (f x)) =
fun x ↦ (((ContinuousLinearEquiv.refl 𝕜 F).arrowCongr L)) ∘L (fderiv 𝕜 f x) := by
ext x : 1
exact fderiv_continuousLinearEquiv_comp L f x
theorem comp_right_differentiableWithinAt_iff {f : F → G} {s : Set F} {x : E} :
DifferentiableWithinAt 𝕜 (f ∘ iso) (iso ⁻¹' s) x ↔ DifferentiableWithinAt 𝕜 f s (iso x) := by
refine ⟨fun H => ?_, fun H => H.comp x iso.differentiableWithinAt (mapsTo_preimage _ s)⟩
have : DifferentiableWithinAt 𝕜 ((f ∘ iso) ∘ iso.symm) s (iso x) := by
rw [← iso.symm_apply_apply x] at H
apply H.comp (iso x) iso.symm.differentiableWithinAt
intro y hy
simpa only [mem_preimage, apply_symm_apply] using hy
rwa [Function.comp.assoc, iso.self_comp_symm] at this
#align continuous_linear_equiv.comp_right_differentiable_within_at_iff ContinuousLinearEquiv.comp_right_differentiableWithinAt_iff
theorem comp_right_differentiableAt_iff {f : F → G} {x : E} :
DifferentiableAt 𝕜 (f ∘ iso) x ↔ DifferentiableAt 𝕜 f (iso x) := by
simp only [← differentiableWithinAt_univ, ← iso.comp_right_differentiableWithinAt_iff,
preimage_univ]
#align continuous_linear_equiv.comp_right_differentiable_at_iff ContinuousLinearEquiv.comp_right_differentiableAt_iff
theorem comp_right_differentiableOn_iff {f : F → G} {s : Set F} :
DifferentiableOn 𝕜 (f ∘ iso) (iso ⁻¹' s) ↔ DifferentiableOn 𝕜 f s := by
refine ⟨fun H y hy => ?_, fun H y hy => iso.comp_right_differentiableWithinAt_iff.2 (H _ hy)⟩
rw [← iso.apply_symm_apply y, ← comp_right_differentiableWithinAt_iff]
apply H
simpa only [mem_preimage, apply_symm_apply] using hy
#align continuous_linear_equiv.comp_right_differentiable_on_iff ContinuousLinearEquiv.comp_right_differentiableOn_iff
theorem comp_right_differentiable_iff {f : F → G} :
Differentiable 𝕜 (f ∘ iso) ↔ Differentiable 𝕜 f := by
simp only [← differentiableOn_univ, ← iso.comp_right_differentiableOn_iff, preimage_univ]
#align continuous_linear_equiv.comp_right_differentiable_iff ContinuousLinearEquiv.comp_right_differentiable_iff
| Mathlib/Analysis/Calculus/FDeriv/Equiv.lean | 221 | 234 | theorem comp_right_hasFDerivWithinAt_iff {f : F → G} {s : Set F} {x : E} {f' : F →L[𝕜] G} :
HasFDerivWithinAt (f ∘ iso) (f'.comp (iso : E →L[𝕜] F)) (iso ⁻¹' s) x ↔
HasFDerivWithinAt f f' s (iso x) := by |
refine ⟨fun H => ?_, fun H => H.comp x iso.hasFDerivWithinAt (mapsTo_preimage _ s)⟩
rw [← iso.symm_apply_apply x] at H
have A : f = (f ∘ iso) ∘ iso.symm := by
rw [Function.comp.assoc, iso.self_comp_symm]
rfl
have B : f' = (f'.comp (iso : E →L[𝕜] F)).comp (iso.symm : F →L[𝕜] E) := by
rw [ContinuousLinearMap.comp_assoc, iso.coe_comp_coe_symm, ContinuousLinearMap.comp_id]
rw [A, B]
apply H.comp (iso x) iso.symm.hasFDerivWithinAt
intro y hy
simpa only [mem_preimage, apply_symm_apply] using hy
|
namespace Nat
@[reducible] def Coprime (m n : Nat) : Prop := gcd m n = 1
instance (m n : Nat) : Decidable (Coprime m n) := inferInstanceAs (Decidable (_ = 1))
theorem coprime_iff_gcd_eq_one : Coprime m n ↔ gcd m n = 1 := .rfl
theorem Coprime.gcd_eq_one : Coprime m n → gcd m n = 1 := id
theorem Coprime.symm : Coprime n m → Coprime m n := (gcd_comm m n).trans
theorem coprime_comm : Coprime n m ↔ Coprime m n := ⟨Coprime.symm, Coprime.symm⟩
theorem Coprime.dvd_of_dvd_mul_right (H1 : Coprime k n) (H2 : k ∣ m * n) : k ∣ m := by
let t := dvd_gcd (Nat.dvd_mul_left k m) H2
rwa [gcd_mul_left, H1.gcd_eq_one, Nat.mul_one] at t
theorem Coprime.dvd_of_dvd_mul_left (H1 : Coprime k m) (H2 : k ∣ m * n) : k ∣ n :=
H1.dvd_of_dvd_mul_right (by rwa [Nat.mul_comm])
theorem Coprime.gcd_mul_left_cancel (m : Nat) (H : Coprime k n) : gcd (k * m) n = gcd m n :=
have H1 : Coprime (gcd (k * m) n) k := by
rw [Coprime, Nat.gcd_assoc, H.symm.gcd_eq_one, gcd_one_right]
Nat.dvd_antisymm
(dvd_gcd (H1.dvd_of_dvd_mul_left (gcd_dvd_left _ _)) (gcd_dvd_right _ _))
(gcd_dvd_gcd_mul_left _ _ _)
theorem Coprime.gcd_mul_right_cancel (m : Nat) (H : Coprime k n) : gcd (m * k) n = gcd m n := by
rw [Nat.mul_comm m k, H.gcd_mul_left_cancel m]
theorem Coprime.gcd_mul_left_cancel_right (n : Nat)
(H : Coprime k m) : gcd m (k * n) = gcd m n := by
rw [gcd_comm m n, gcd_comm m (k * n), H.gcd_mul_left_cancel n]
theorem Coprime.gcd_mul_right_cancel_right (n : Nat)
(H : Coprime k m) : gcd m (n * k) = gcd m n := by
rw [Nat.mul_comm n k, H.gcd_mul_left_cancel_right n]
theorem coprime_div_gcd_div_gcd
(H : 0 < gcd m n) : Coprime (m / gcd m n) (n / gcd m n) := by
rw [coprime_iff_gcd_eq_one, gcd_div (gcd_dvd_left m n) (gcd_dvd_right m n), Nat.div_self H]
theorem not_coprime_of_dvd_of_dvd (dgt1 : 1 < d) (Hm : d ∣ m) (Hn : d ∣ n) : ¬ Coprime m n :=
fun co => Nat.not_le_of_gt dgt1 <| Nat.le_of_dvd Nat.zero_lt_one <| by
rw [← co.gcd_eq_one]; exact dvd_gcd Hm Hn
| .lake/packages/batteries/Batteries/Data/Nat/Gcd.lean | 65 | 75 | theorem exists_coprime (m n : Nat) :
∃ m' n', Coprime m' n' ∧ m = m' * gcd m n ∧ n = n' * gcd m n := by |
cases eq_zero_or_pos (gcd m n) with
| inl h0 =>
rw [gcd_eq_zero_iff] at h0
refine ⟨1, 1, gcd_one_left 1, ?_⟩
simp [h0]
| inr hpos =>
exact ⟨_, _, coprime_div_gcd_div_gcd hpos,
(Nat.div_mul_cancel (gcd_dvd_left m n)).symm,
(Nat.div_mul_cancel (gcd_dvd_right m n)).symm⟩
|
import Mathlib.Analysis.SpecialFunctions.ImproperIntegrals
import Mathlib.Analysis.Calculus.ParametricIntegral
import Mathlib.MeasureTheory.Measure.Haar.NormedSpace
#align_import analysis.mellin_transform from "leanprover-community/mathlib"@"917c3c072e487b3cccdbfeff17e75b40e45f66cb"
open MeasureTheory Set Filter Asymptotics TopologicalSpace
open Real
open Complex hiding exp log abs_of_nonneg
open scoped Topology
noncomputable section
variable {E : Type*} [NormedAddCommGroup E]
section MellinDiff
| Mathlib/Analysis/MellinTransform.lean | 304 | 312 | theorem isBigO_rpow_top_log_smul [NormedSpace ℝ E] {a b : ℝ} {f : ℝ → E} (hab : b < a)
(hf : f =O[atTop] (· ^ (-a))) :
(fun t : ℝ => log t • f t) =O[atTop] (· ^ (-b)) := by |
refine
((isLittleO_log_rpow_atTop (sub_pos.mpr hab)).isBigO.smul hf).congr'
(eventually_of_forall fun t => by rfl)
((eventually_gt_atTop 0).mp (eventually_of_forall fun t ht => ?_))
simp only
rw [smul_eq_mul, ← rpow_add ht, ← sub_eq_add_neg, sub_eq_add_neg a, add_sub_cancel_left]
|
import Mathlib.Algebra.BigOperators.Fin
import Mathlib.Algebra.Order.BigOperators.Group.Finset
import Mathlib.Data.Finset.Sort
import Mathlib.Data.Set.Subsingleton
#align_import combinatorics.composition from "leanprover-community/mathlib"@"92ca63f0fb391a9ca5f22d2409a6080e786d99f7"
open List
variable {n : ℕ}
@[ext]
structure Composition (n : ℕ) where
blocks : List ℕ
blocks_pos : ∀ {i}, i ∈ blocks → 0 < i
blocks_sum : blocks.sum = n
#align composition Composition
@[ext]
structure CompositionAsSet (n : ℕ) where
boundaries : Finset (Fin n.succ)
zero_mem : (0 : Fin n.succ) ∈ boundaries
getLast_mem : Fin.last n ∈ boundaries
#align composition_as_set CompositionAsSet
instance {n : ℕ} : Inhabited (CompositionAsSet n) :=
⟨⟨Finset.univ, Finset.mem_univ _, Finset.mem_univ _⟩⟩
namespace Composition
variable (c : Composition n)
instance (n : ℕ) : ToString (Composition n) :=
⟨fun c => toString c.blocks⟩
abbrev length : ℕ :=
c.blocks.length
#align composition.length Composition.length
theorem blocks_length : c.blocks.length = c.length :=
rfl
#align composition.blocks_length Composition.blocks_length
def blocksFun : Fin c.length → ℕ := c.blocks.get
#align composition.blocks_fun Composition.blocksFun
theorem ofFn_blocksFun : ofFn c.blocksFun = c.blocks :=
ofFn_get _
#align composition.of_fn_blocks_fun Composition.ofFn_blocksFun
theorem sum_blocksFun : ∑ i, c.blocksFun i = n := by
conv_rhs => rw [← c.blocks_sum, ← ofFn_blocksFun, sum_ofFn]
#align composition.sum_blocks_fun Composition.sum_blocksFun
theorem blocksFun_mem_blocks (i : Fin c.length) : c.blocksFun i ∈ c.blocks :=
get_mem _ _ _
#align composition.blocks_fun_mem_blocks Composition.blocksFun_mem_blocks
@[simp]
theorem one_le_blocks {i : ℕ} (h : i ∈ c.blocks) : 1 ≤ i :=
c.blocks_pos h
#align composition.one_le_blocks Composition.one_le_blocks
@[simp]
theorem one_le_blocks' {i : ℕ} (h : i < c.length) : 1 ≤ c.blocks.get ⟨i, h⟩ :=
c.one_le_blocks (get_mem (blocks c) i h)
#align composition.one_le_blocks' Composition.one_le_blocks'
@[simp]
theorem blocks_pos' (i : ℕ) (h : i < c.length) : 0 < c.blocks.get ⟨i, h⟩ :=
c.one_le_blocks' h
#align composition.blocks_pos' Composition.blocks_pos'
theorem one_le_blocksFun (i : Fin c.length) : 1 ≤ c.blocksFun i :=
c.one_le_blocks (c.blocksFun_mem_blocks i)
#align composition.one_le_blocks_fun Composition.one_le_blocksFun
theorem length_le : c.length ≤ n := by
conv_rhs => rw [← c.blocks_sum]
exact length_le_sum_of_one_le _ fun i hi => c.one_le_blocks hi
#align composition.length_le Composition.length_le
theorem length_pos_of_pos (h : 0 < n) : 0 < c.length := by
apply length_pos_of_sum_pos
convert h
exact c.blocks_sum
#align composition.length_pos_of_pos Composition.length_pos_of_pos
def sizeUpTo (i : ℕ) : ℕ :=
(c.blocks.take i).sum
#align composition.size_up_to Composition.sizeUpTo
@[simp]
theorem sizeUpTo_zero : c.sizeUpTo 0 = 0 := by simp [sizeUpTo]
#align composition.size_up_to_zero Composition.sizeUpTo_zero
theorem sizeUpTo_ofLength_le (i : ℕ) (h : c.length ≤ i) : c.sizeUpTo i = n := by
dsimp [sizeUpTo]
convert c.blocks_sum
exact take_all_of_le h
#align composition.size_up_to_of_length_le Composition.sizeUpTo_ofLength_le
@[simp]
theorem sizeUpTo_length : c.sizeUpTo c.length = n :=
c.sizeUpTo_ofLength_le c.length le_rfl
#align composition.size_up_to_length Composition.sizeUpTo_length
theorem sizeUpTo_le (i : ℕ) : c.sizeUpTo i ≤ n := by
conv_rhs => rw [← c.blocks_sum, ← sum_take_add_sum_drop _ i]
exact Nat.le_add_right _ _
#align composition.size_up_to_le Composition.sizeUpTo_le
theorem sizeUpTo_succ {i : ℕ} (h : i < c.length) :
c.sizeUpTo (i + 1) = c.sizeUpTo i + c.blocks.get ⟨i, h⟩ := by
simp only [sizeUpTo]
rw [sum_take_succ _ _ h]
#align composition.size_up_to_succ Composition.sizeUpTo_succ
theorem sizeUpTo_succ' (i : Fin c.length) :
c.sizeUpTo ((i : ℕ) + 1) = c.sizeUpTo i + c.blocksFun i :=
c.sizeUpTo_succ i.2
#align composition.size_up_to_succ' Composition.sizeUpTo_succ'
theorem sizeUpTo_strict_mono {i : ℕ} (h : i < c.length) : c.sizeUpTo i < c.sizeUpTo (i + 1) := by
rw [c.sizeUpTo_succ h]
simp
#align composition.size_up_to_strict_mono Composition.sizeUpTo_strict_mono
theorem monotone_sizeUpTo : Monotone c.sizeUpTo :=
monotone_sum_take _
#align composition.monotone_size_up_to Composition.monotone_sizeUpTo
def boundary : Fin (c.length + 1) ↪o Fin (n + 1) :=
(OrderEmbedding.ofStrictMono fun i => ⟨c.sizeUpTo i, Nat.lt_succ_of_le (c.sizeUpTo_le i)⟩) <|
Fin.strictMono_iff_lt_succ.2 fun ⟨_, hi⟩ => c.sizeUpTo_strict_mono hi
#align composition.boundary Composition.boundary
@[simp]
theorem boundary_zero : c.boundary 0 = 0 := by simp [boundary, Fin.ext_iff]
#align composition.boundary_zero Composition.boundary_zero
@[simp]
theorem boundary_last : c.boundary (Fin.last c.length) = Fin.last n := by
simp [boundary, Fin.ext_iff]
#align composition.boundary_last Composition.boundary_last
def boundaries : Finset (Fin (n + 1)) :=
Finset.univ.map c.boundary.toEmbedding
#align composition.boundaries Composition.boundaries
theorem card_boundaries_eq_succ_length : c.boundaries.card = c.length + 1 := by simp [boundaries]
#align composition.card_boundaries_eq_succ_length Composition.card_boundaries_eq_succ_length
def toCompositionAsSet : CompositionAsSet n where
boundaries := c.boundaries
zero_mem := by
simp only [boundaries, Finset.mem_univ, exists_prop_of_true, Finset.mem_map]
exact ⟨0, And.intro True.intro rfl⟩
getLast_mem := by
simp only [boundaries, Finset.mem_univ, exists_prop_of_true, Finset.mem_map]
exact ⟨Fin.last c.length, And.intro True.intro c.boundary_last⟩
#align composition.to_composition_as_set Composition.toCompositionAsSet
theorem orderEmbOfFin_boundaries :
c.boundaries.orderEmbOfFin c.card_boundaries_eq_succ_length = c.boundary := by
refine (Finset.orderEmbOfFin_unique' _ ?_).symm
exact fun i => (Finset.mem_map' _).2 (Finset.mem_univ _)
#align composition.order_emb_of_fin_boundaries Composition.orderEmbOfFin_boundaries
def embedding (i : Fin c.length) : Fin (c.blocksFun i) ↪o Fin n :=
(Fin.natAddOrderEmb <| c.sizeUpTo i).trans <| Fin.castLEOrderEmb <|
calc
c.sizeUpTo i + c.blocksFun i = c.sizeUpTo (i + 1) := (c.sizeUpTo_succ _).symm
_ ≤ c.sizeUpTo c.length := monotone_sum_take _ i.2
_ = n := c.sizeUpTo_length
#align composition.embedding Composition.embedding
@[simp]
theorem coe_embedding (i : Fin c.length) (j : Fin (c.blocksFun i)) :
(c.embedding i j : ℕ) = c.sizeUpTo i + j :=
rfl
#align composition.coe_embedding Composition.coe_embedding
theorem index_exists {j : ℕ} (h : j < n) : ∃ i : ℕ, j < c.sizeUpTo (i + 1) ∧ i < c.length := by
have n_pos : 0 < n := lt_of_le_of_lt (zero_le j) h
have : 0 < c.blocks.sum := by rwa [← c.blocks_sum] at n_pos
have length_pos : 0 < c.blocks.length := length_pos_of_sum_pos (blocks c) this
refine ⟨c.length - 1, ?_, Nat.pred_lt (ne_of_gt length_pos)⟩
have : c.length - 1 + 1 = c.length := Nat.succ_pred_eq_of_pos length_pos
simp [this, h]
#align composition.index_exists Composition.index_exists
def index (j : Fin n) : Fin c.length :=
⟨Nat.find (c.index_exists j.2), (Nat.find_spec (c.index_exists j.2)).2⟩
#align composition.index Composition.index
theorem lt_sizeUpTo_index_succ (j : Fin n) : (j : ℕ) < c.sizeUpTo (c.index j).succ :=
(Nat.find_spec (c.index_exists j.2)).1
#align composition.lt_size_up_to_index_succ Composition.lt_sizeUpTo_index_succ
theorem sizeUpTo_index_le (j : Fin n) : c.sizeUpTo (c.index j) ≤ j := by
by_contra H
set i := c.index j
push_neg at H
have i_pos : (0 : ℕ) < i := by
by_contra! i_pos
revert H
simp [nonpos_iff_eq_zero.1 i_pos, c.sizeUpTo_zero]
let i₁ := (i : ℕ).pred
have i₁_lt_i : i₁ < i := Nat.pred_lt (ne_of_gt i_pos)
have i₁_succ : i₁ + 1 = i := Nat.succ_pred_eq_of_pos i_pos
have := Nat.find_min (c.index_exists j.2) i₁_lt_i
simp [lt_trans i₁_lt_i (c.index j).2, i₁_succ] at this
exact Nat.lt_le_asymm H this
#align composition.size_up_to_index_le Composition.sizeUpTo_index_le
def invEmbedding (j : Fin n) : Fin (c.blocksFun (c.index j)) :=
⟨j - c.sizeUpTo (c.index j), by
rw [tsub_lt_iff_right, add_comm, ← sizeUpTo_succ']
· exact lt_sizeUpTo_index_succ _ _
· exact sizeUpTo_index_le _ _⟩
#align composition.inv_embedding Composition.invEmbedding
@[simp]
theorem coe_invEmbedding (j : Fin n) : (c.invEmbedding j : ℕ) = j - c.sizeUpTo (c.index j) :=
rfl
#align composition.coe_inv_embedding Composition.coe_invEmbedding
theorem embedding_comp_inv (j : Fin n) : c.embedding (c.index j) (c.invEmbedding j) = j := by
rw [Fin.ext_iff]
apply add_tsub_cancel_of_le (c.sizeUpTo_index_le j)
#align composition.embedding_comp_inv Composition.embedding_comp_inv
theorem mem_range_embedding_iff {j : Fin n} {i : Fin c.length} :
j ∈ Set.range (c.embedding i) ↔ c.sizeUpTo i ≤ j ∧ (j : ℕ) < c.sizeUpTo (i : ℕ).succ := by
constructor
· intro h
rcases Set.mem_range.2 h with ⟨k, hk⟩
rw [Fin.ext_iff] at hk
dsimp at hk
rw [← hk]
simp [sizeUpTo_succ', k.is_lt]
· intro h
apply Set.mem_range.2
refine ⟨⟨j - c.sizeUpTo i, ?_⟩, ?_⟩
· rw [tsub_lt_iff_left, ← sizeUpTo_succ']
· exact h.2
· exact h.1
· rw [Fin.ext_iff]
exact add_tsub_cancel_of_le h.1
#align composition.mem_range_embedding_iff Composition.mem_range_embedding_iff
theorem disjoint_range {i₁ i₂ : Fin c.length} (h : i₁ ≠ i₂) :
Disjoint (Set.range (c.embedding i₁)) (Set.range (c.embedding i₂)) := by
classical
wlog h' : i₁ < i₂
· exact (this c h.symm (h.lt_or_lt.resolve_left h')).symm
by_contra d
obtain ⟨x, hx₁, hx₂⟩ :
∃ x : Fin n, x ∈ Set.range (c.embedding i₁) ∧ x ∈ Set.range (c.embedding i₂) :=
Set.not_disjoint_iff.1 d
have A : (i₁ : ℕ).succ ≤ i₂ := Nat.succ_le_of_lt h'
apply lt_irrefl (x : ℕ)
calc
(x : ℕ) < c.sizeUpTo (i₁ : ℕ).succ := (c.mem_range_embedding_iff.1 hx₁).2
_ ≤ c.sizeUpTo (i₂ : ℕ) := monotone_sum_take _ A
_ ≤ x := (c.mem_range_embedding_iff.1 hx₂).1
#align composition.disjoint_range Composition.disjoint_range
theorem mem_range_embedding (j : Fin n) : j ∈ Set.range (c.embedding (c.index j)) := by
have : c.embedding (c.index j) (c.invEmbedding j) ∈ Set.range (c.embedding (c.index j)) :=
Set.mem_range_self _
rwa [c.embedding_comp_inv j] at this
#align composition.mem_range_embedding Composition.mem_range_embedding
theorem mem_range_embedding_iff' {j : Fin n} {i : Fin c.length} :
j ∈ Set.range (c.embedding i) ↔ i = c.index j := by
constructor
· rw [← not_imp_not]
intro h
exact Set.disjoint_right.1 (c.disjoint_range h) (c.mem_range_embedding j)
· intro h
rw [h]
exact c.mem_range_embedding j
#align composition.mem_range_embedding_iff' Composition.mem_range_embedding_iff'
theorem index_embedding (i : Fin c.length) (j : Fin (c.blocksFun i)) :
c.index (c.embedding i j) = i := by
symm
rw [← mem_range_embedding_iff']
apply Set.mem_range_self
#align composition.index_embedding Composition.index_embedding
theorem invEmbedding_comp (i : Fin c.length) (j : Fin (c.blocksFun i)) :
(c.invEmbedding (c.embedding i j) : ℕ) = j := by
simp_rw [coe_invEmbedding, index_embedding, coe_embedding, add_tsub_cancel_left]
#align composition.inv_embedding_comp Composition.invEmbedding_comp
def blocksFinEquiv : (Σi : Fin c.length, Fin (c.blocksFun i)) ≃ Fin n where
toFun x := c.embedding x.1 x.2
invFun j := ⟨c.index j, c.invEmbedding j⟩
left_inv x := by
rcases x with ⟨i, y⟩
dsimp
congr; · exact c.index_embedding _ _
rw [Fin.heq_ext_iff]
· exact c.invEmbedding_comp _ _
· rw [c.index_embedding]
right_inv j := c.embedding_comp_inv j
#align composition.blocks_fin_equiv Composition.blocksFinEquiv
theorem blocksFun_congr {n₁ n₂ : ℕ} (c₁ : Composition n₁) (c₂ : Composition n₂) (i₁ : Fin c₁.length)
(i₂ : Fin c₂.length) (hn : n₁ = n₂) (hc : c₁.blocks = c₂.blocks) (hi : (i₁ : ℕ) = i₂) :
c₁.blocksFun i₁ = c₂.blocksFun i₂ := by
cases hn
rw [← Composition.ext_iff] at hc
cases hc
congr
rwa [Fin.ext_iff]
#align composition.blocks_fun_congr Composition.blocksFun_congr
theorem sigma_eq_iff_blocks_eq {c : Σn, Composition n} {c' : Σn, Composition n} :
c = c' ↔ c.2.blocks = c'.2.blocks := by
refine ⟨fun H => by rw [H], fun H => ?_⟩
rcases c with ⟨n, c⟩
rcases c' with ⟨n', c'⟩
have : n = n' := by rw [← c.blocks_sum, ← c'.blocks_sum, H]
induction this
congr
ext1
exact H
#align composition.sigma_eq_iff_blocks_eq Composition.sigma_eq_iff_blocks_eq
def ones (n : ℕ) : Composition n :=
⟨replicate n (1 : ℕ), fun {i} hi => by simp [List.eq_of_mem_replicate hi], by simp⟩
#align composition.ones Composition.ones
instance {n : ℕ} : Inhabited (Composition n) :=
⟨Composition.ones n⟩
@[simp]
theorem ones_length (n : ℕ) : (ones n).length = n :=
List.length_replicate n 1
#align composition.ones_length Composition.ones_length
@[simp]
theorem ones_blocks (n : ℕ) : (ones n).blocks = replicate n (1 : ℕ) :=
rfl
#align composition.ones_blocks Composition.ones_blocks
@[simp]
theorem ones_blocksFun (n : ℕ) (i : Fin (ones n).length) : (ones n).blocksFun i = 1 := by
simp only [blocksFun, ones, blocks, i.2, List.get_replicate]
#align composition.ones_blocks_fun Composition.ones_blocksFun
@[simp]
theorem ones_sizeUpTo (n : ℕ) (i : ℕ) : (ones n).sizeUpTo i = min i n := by
simp [sizeUpTo, ones_blocks, take_replicate]
#align composition.ones_size_up_to Composition.ones_sizeUpTo
@[simp]
theorem ones_embedding (i : Fin (ones n).length) (h : 0 < (ones n).blocksFun i) :
(ones n).embedding i ⟨0, h⟩ = ⟨i, lt_of_lt_of_le i.2 (ones n).length_le⟩ := by
ext
simpa using i.2.le
#align composition.ones_embedding Composition.ones_embedding
theorem eq_ones_iff {c : Composition n} : c = ones n ↔ ∀ i ∈ c.blocks, i = 1 := by
constructor
· rintro rfl
exact fun i => eq_of_mem_replicate
· intro H
ext1
have A : c.blocks = replicate c.blocks.length 1 := eq_replicate_of_mem H
have : c.blocks.length = n := by
conv_rhs => rw [← c.blocks_sum, A]
simp
rw [A, this, ones_blocks]
#align composition.eq_ones_iff Composition.eq_ones_iff
theorem ne_ones_iff {c : Composition n} : c ≠ ones n ↔ ∃ i ∈ c.blocks, 1 < i := by
refine (not_congr eq_ones_iff).trans ?_
have : ∀ j ∈ c.blocks, j = 1 ↔ j ≤ 1 := fun j hj => by simp [le_antisymm_iff, c.one_le_blocks hj]
simp (config := { contextual := true }) [this]
#align composition.ne_ones_iff Composition.ne_ones_iff
theorem eq_ones_iff_length {c : Composition n} : c = ones n ↔ c.length = n := by
constructor
· rintro rfl
exact ones_length n
· contrapose
intro H length_n
apply lt_irrefl n
calc
n = ∑ i : Fin c.length, 1 := by simp [length_n]
_ < ∑ i : Fin c.length, c.blocksFun i := by
{
obtain ⟨i, hi, i_blocks⟩ : ∃ i ∈ c.blocks, 1 < i := ne_ones_iff.1 H
rw [← ofFn_blocksFun, mem_ofFn c.blocksFun, Set.mem_range] at hi
obtain ⟨j : Fin c.length, hj : c.blocksFun j = i⟩ := hi
rw [← hj] at i_blocks
exact Finset.sum_lt_sum (fun i _ => one_le_blocksFun c i) ⟨j, Finset.mem_univ _, i_blocks⟩
}
_ = n := c.sum_blocksFun
#align composition.eq_ones_iff_length Composition.eq_ones_iff_length
theorem eq_ones_iff_le_length {c : Composition n} : c = ones n ↔ n ≤ c.length := by
simp [eq_ones_iff_length, le_antisymm_iff, c.length_le]
#align composition.eq_ones_iff_le_length Composition.eq_ones_iff_le_length
def single (n : ℕ) (h : 0 < n) : Composition n :=
⟨[n], by simp [h], by simp⟩
#align composition.single Composition.single
@[simp]
theorem single_length {n : ℕ} (h : 0 < n) : (single n h).length = 1 :=
rfl
#align composition.single_length Composition.single_length
@[simp]
theorem single_blocks {n : ℕ} (h : 0 < n) : (single n h).blocks = [n] :=
rfl
#align composition.single_blocks Composition.single_blocks
@[simp]
| Mathlib/Combinatorics/Enumerative/Composition.lean | 566 | 567 | theorem single_blocksFun {n : ℕ} (h : 0 < n) (i : Fin (single n h).length) :
(single n h).blocksFun i = n := by | simp [blocksFun, single, blocks, i.2]
|
import Mathlib.Data.Bool.Basic
import Mathlib.Data.Option.Defs
import Mathlib.Data.Prod.Basic
import Mathlib.Data.Sigma.Basic
import Mathlib.Data.Subtype
import Mathlib.Data.Sum.Basic
import Mathlib.Init.Data.Sigma.Basic
import Mathlib.Logic.Equiv.Defs
import Mathlib.Logic.Function.Conjugate
import Mathlib.Tactic.Lift
import Mathlib.Tactic.Convert
import Mathlib.Tactic.Contrapose
import Mathlib.Tactic.GeneralizeProofs
import Mathlib.Tactic.SimpRw
#align_import logic.equiv.basic from "leanprover-community/mathlib"@"cd391184c85986113f8c00844cfe6dda1d34be3d"
set_option autoImplicit true
universe u
open Function
namespace Equiv
@[simps apply symm_apply]
def pprodEquivProd : PProd α β ≃ α × β where
toFun x := (x.1, x.2)
invFun x := ⟨x.1, x.2⟩
left_inv := fun _ => rfl
right_inv := fun _ => rfl
#align equiv.pprod_equiv_prod Equiv.pprodEquivProd
#align equiv.pprod_equiv_prod_apply Equiv.pprodEquivProd_apply
#align equiv.pprod_equiv_prod_symm_apply Equiv.pprodEquivProd_symm_apply
-- Porting note: in Lean 3 this had `@[congr]`
@[simps apply]
def pprodCongr (e₁ : α ≃ β) (e₂ : γ ≃ δ) : PProd α γ ≃ PProd β δ where
toFun x := ⟨e₁ x.1, e₂ x.2⟩
invFun x := ⟨e₁.symm x.1, e₂.symm x.2⟩
left_inv := fun ⟨x, y⟩ => by simp
right_inv := fun ⟨x, y⟩ => by simp
#align equiv.pprod_congr Equiv.pprodCongr
#align equiv.pprod_congr_apply Equiv.pprodCongr_apply
@[simps! apply symm_apply]
def pprodProd (ea : α₁ ≃ α₂) (eb : β₁ ≃ β₂) :
PProd α₁ β₁ ≃ α₂ × β₂ :=
(ea.pprodCongr eb).trans pprodEquivProd
#align equiv.pprod_prod Equiv.pprodProd
#align equiv.pprod_prod_apply Equiv.pprodProd_apply
#align equiv.pprod_prod_symm_apply Equiv.pprodProd_symm_apply
@[simps! apply symm_apply]
def prodPProd (ea : α₁ ≃ α₂) (eb : β₁ ≃ β₂) :
α₁ × β₁ ≃ PProd α₂ β₂ :=
(ea.symm.pprodProd eb.symm).symm
#align equiv.prod_pprod Equiv.prodPProd
#align equiv.prod_pprod_symm_apply Equiv.prodPProd_symm_apply
#align equiv.prod_pprod_apply Equiv.prodPProd_apply
@[simps! apply symm_apply]
def pprodEquivProdPLift : PProd α β ≃ PLift α × PLift β :=
Equiv.plift.symm.pprodProd Equiv.plift.symm
#align equiv.pprod_equiv_prod_plift Equiv.pprodEquivProdPLift
#align equiv.pprod_equiv_prod_plift_symm_apply Equiv.pprodEquivProdPLift_symm_apply
#align equiv.pprod_equiv_prod_plift_apply Equiv.pprodEquivProdPLift_apply
-- Porting note: in Lean 3 there was also a @[congr] tag
@[simps (config := .asFn) apply]
def prodCongr (e₁ : α₁ ≃ α₂) (e₂ : β₁ ≃ β₂) : α₁ × β₁ ≃ α₂ × β₂ :=
⟨Prod.map e₁ e₂, Prod.map e₁.symm e₂.symm, fun ⟨a, b⟩ => by simp, fun ⟨a, b⟩ => by simp⟩
#align equiv.prod_congr Equiv.prodCongr
#align equiv.prod_congr_apply Equiv.prodCongr_apply
@[simp]
theorem prodCongr_symm (e₁ : α₁ ≃ α₂) (e₂ : β₁ ≃ β₂) :
(prodCongr e₁ e₂).symm = prodCongr e₁.symm e₂.symm :=
rfl
#align equiv.prod_congr_symm Equiv.prodCongr_symm
def prodComm (α β) : α × β ≃ β × α :=
⟨Prod.swap, Prod.swap, Prod.swap_swap, Prod.swap_swap⟩
#align equiv.prod_comm Equiv.prodComm
@[simp]
theorem coe_prodComm (α β) : (⇑(prodComm α β) : α × β → β × α) = Prod.swap :=
rfl
#align equiv.coe_prod_comm Equiv.coe_prodComm
@[simp]
theorem prodComm_apply (x : α × β) : prodComm α β x = x.swap :=
rfl
#align equiv.prod_comm_apply Equiv.prodComm_apply
@[simp]
theorem prodComm_symm (α β) : (prodComm α β).symm = prodComm β α :=
rfl
#align equiv.prod_comm_symm Equiv.prodComm_symm
@[simps]
def prodAssoc (α β γ) : (α × β) × γ ≃ α × β × γ :=
⟨fun p => (p.1.1, p.1.2, p.2), fun p => ((p.1, p.2.1), p.2.2), fun ⟨⟨_, _⟩, _⟩ => rfl,
fun ⟨_, ⟨_, _⟩⟩ => rfl⟩
#align equiv.prod_assoc Equiv.prodAssoc
#align equiv.prod_assoc_symm_apply Equiv.prodAssoc_symm_apply
#align equiv.prod_assoc_apply Equiv.prodAssoc_apply
@[simps apply]
def prodProdProdComm (α β γ δ : Type*) : (α × β) × γ × δ ≃ (α × γ) × β × δ where
toFun abcd := ((abcd.1.1, abcd.2.1), (abcd.1.2, abcd.2.2))
invFun acbd := ((acbd.1.1, acbd.2.1), (acbd.1.2, acbd.2.2))
left_inv := fun ⟨⟨_a, _b⟩, ⟨_c, _d⟩⟩ => rfl
right_inv := fun ⟨⟨_a, _c⟩, ⟨_b, _d⟩⟩ => rfl
#align equiv.prod_prod_prod_comm Equiv.prodProdProdComm
@[simp]
theorem prodProdProdComm_symm (α β γ δ : Type*) :
(prodProdProdComm α β γ δ).symm = prodProdProdComm α γ β δ :=
rfl
#align equiv.prod_prod_prod_comm_symm Equiv.prodProdProdComm_symm
@[simps (config := .asFn)]
def curry (α β γ) : (α × β → γ) ≃ (α → β → γ) where
toFun := Function.curry
invFun := uncurry
left_inv := uncurry_curry
right_inv := curry_uncurry
#align equiv.curry Equiv.curry
#align equiv.curry_symm_apply Equiv.curry_symm_apply
#align equiv.curry_apply Equiv.curry_apply
section
@[simps]
def prodPUnit (α) : α × PUnit ≃ α :=
⟨fun p => p.1, fun a => (a, PUnit.unit), fun ⟨_, PUnit.unit⟩ => rfl, fun _ => rfl⟩
#align equiv.prod_punit Equiv.prodPUnit
#align equiv.prod_punit_apply Equiv.prodPUnit_apply
#align equiv.prod_punit_symm_apply Equiv.prodPUnit_symm_apply
@[simps!]
def punitProd (α) : PUnit × α ≃ α :=
calc
PUnit × α ≃ α × PUnit := prodComm _ _
_ ≃ α := prodPUnit _
#align equiv.punit_prod Equiv.punitProd
#align equiv.punit_prod_symm_apply Equiv.punitProd_symm_apply
#align equiv.punit_prod_apply Equiv.punitProd_apply
@[simps]
def sigmaPUnit (α) : (_ : α) × PUnit ≃ α :=
⟨fun p => p.1, fun a => ⟨a, PUnit.unit⟩, fun ⟨_, PUnit.unit⟩ => rfl, fun _ => rfl⟩
def prodUnique (α β) [Unique β] : α × β ≃ α :=
((Equiv.refl α).prodCongr <| equivPUnit.{_,1} β).trans <| prodPUnit α
#align equiv.prod_unique Equiv.prodUnique
@[simp]
theorem coe_prodUnique [Unique β] : (⇑(prodUnique α β) : α × β → α) = Prod.fst :=
rfl
#align equiv.coe_prod_unique Equiv.coe_prodUnique
theorem prodUnique_apply [Unique β] (x : α × β) : prodUnique α β x = x.1 :=
rfl
#align equiv.prod_unique_apply Equiv.prodUnique_apply
@[simp]
theorem prodUnique_symm_apply [Unique β] (x : α) :
(prodUnique α β).symm x = (x, default) :=
rfl
#align equiv.prod_unique_symm_apply Equiv.prodUnique_symm_apply
def uniqueProd (α β) [Unique β] : β × α ≃ α :=
((equivPUnit.{_,1} β).prodCongr <| Equiv.refl α).trans <| punitProd α
#align equiv.unique_prod Equiv.uniqueProd
@[simp]
theorem coe_uniqueProd [Unique β] : (⇑(uniqueProd α β) : β × α → α) = Prod.snd :=
rfl
#align equiv.coe_unique_prod Equiv.coe_uniqueProd
theorem uniqueProd_apply [Unique β] (x : β × α) : uniqueProd α β x = x.2 :=
rfl
#align equiv.unique_prod_apply Equiv.uniqueProd_apply
@[simp]
theorem uniqueProd_symm_apply [Unique β] (x : α) :
(uniqueProd α β).symm x = (default, x) :=
rfl
#align equiv.unique_prod_symm_apply Equiv.uniqueProd_symm_apply
def sigmaUnique (α) (β : α → Type*) [∀ a, Unique (β a)] : (a : α) × (β a) ≃ α :=
(Equiv.sigmaCongrRight fun a ↦ equivPUnit.{_,1} (β a)).trans <| sigmaPUnit α
@[simp]
theorem coe_sigmaUnique {β : α → Type*} [∀ a, Unique (β a)] :
(⇑(sigmaUnique α β) : (a : α) × (β a) → α) = Sigma.fst :=
rfl
theorem sigmaUnique_apply {β : α → Type*} [∀ a, Unique (β a)] (x : (a : α) × β a) :
sigmaUnique α β x = x.1 :=
rfl
@[simp]
theorem sigmaUnique_symm_apply {β : α → Type*} [∀ a, Unique (β a)] (x : α) :
(sigmaUnique α β).symm x = ⟨x, default⟩ :=
rfl
def prodEmpty (α) : α × Empty ≃ Empty :=
equivEmpty _
#align equiv.prod_empty Equiv.prodEmpty
def emptyProd (α) : Empty × α ≃ Empty :=
equivEmpty _
#align equiv.empty_prod Equiv.emptyProd
def prodPEmpty (α) : α × PEmpty ≃ PEmpty :=
equivPEmpty _
#align equiv.prod_pempty Equiv.prodPEmpty
def pemptyProd (α) : PEmpty × α ≃ PEmpty :=
equivPEmpty _
#align equiv.pempty_prod Equiv.pemptyProd
end
section
open Sum
def psumEquivSum (α β) : PSum α β ≃ Sum α β where
toFun s := PSum.casesOn s inl inr
invFun := Sum.elim PSum.inl PSum.inr
left_inv s := by cases s <;> rfl
right_inv s := by cases s <;> rfl
#align equiv.psum_equiv_sum Equiv.psumEquivSum
@[simps apply]
def sumCongr (ea : α₁ ≃ α₂) (eb : β₁ ≃ β₂) : Sum α₁ β₁ ≃ Sum α₂ β₂ :=
⟨Sum.map ea eb, Sum.map ea.symm eb.symm, fun x => by simp, fun x => by simp⟩
#align equiv.sum_congr Equiv.sumCongr
#align equiv.sum_congr_apply Equiv.sumCongr_apply
def psumCongr (e₁ : α ≃ β) (e₂ : γ ≃ δ) : PSum α γ ≃ PSum β δ where
toFun x := PSum.casesOn x (PSum.inl ∘ e₁) (PSum.inr ∘ e₂)
invFun x := PSum.casesOn x (PSum.inl ∘ e₁.symm) (PSum.inr ∘ e₂.symm)
left_inv := by rintro (x | x) <;> simp
right_inv := by rintro (x | x) <;> simp
#align equiv.psum_congr Equiv.psumCongr
def psumSum (ea : α₁ ≃ α₂) (eb : β₁ ≃ β₂) :
PSum α₁ β₁ ≃ Sum α₂ β₂ :=
(ea.psumCongr eb).trans (psumEquivSum _ _)
#align equiv.psum_sum Equiv.psumSum
def sumPSum (ea : α₁ ≃ α₂) (eb : β₁ ≃ β₂) :
Sum α₁ β₁ ≃ PSum α₂ β₂ :=
(ea.symm.psumSum eb.symm).symm
#align equiv.sum_psum Equiv.sumPSum
@[simp]
theorem sumCongr_trans (e : α₁ ≃ β₁) (f : α₂ ≃ β₂) (g : β₁ ≃ γ₁) (h : β₂ ≃ γ₂) :
(Equiv.sumCongr e f).trans (Equiv.sumCongr g h) = Equiv.sumCongr (e.trans g) (f.trans h) := by
ext i
cases i <;> rfl
#align equiv.sum_congr_trans Equiv.sumCongr_trans
@[simp]
theorem sumCongr_symm (e : α ≃ β) (f : γ ≃ δ) :
(Equiv.sumCongr e f).symm = Equiv.sumCongr e.symm f.symm :=
rfl
#align equiv.sum_congr_symm Equiv.sumCongr_symm
@[simp]
theorem sumCongr_refl : Equiv.sumCongr (Equiv.refl α) (Equiv.refl β) = Equiv.refl (Sum α β) := by
ext i
cases i <;> rfl
#align equiv.sum_congr_refl Equiv.sumCongr_refl
def subtypeSum {p : α ⊕ β → Prop} : {c // p c} ≃ {a // p (Sum.inl a)} ⊕ {b // p (Sum.inr b)} where
toFun c := match h : c.1 with
| Sum.inl a => Sum.inl ⟨a, h ▸ c.2⟩
| Sum.inr b => Sum.inr ⟨b, h ▸ c.2⟩
invFun c := match c with
| Sum.inl a => ⟨Sum.inl a, a.2⟩
| Sum.inr b => ⟨Sum.inr b, b.2⟩
left_inv := by rintro ⟨a | b, h⟩ <;> rfl
right_inv := by rintro (a | b) <;> rfl
def boolEquivPUnitSumPUnit : Bool ≃ Sum PUnit.{u + 1} PUnit.{v + 1} :=
⟨fun b => b.casesOn (inl PUnit.unit) (inr PUnit.unit) , Sum.elim (fun _ => false) fun _ => true,
fun b => by cases b <;> rfl, fun s => by rcases s with (⟨⟨⟩⟩ | ⟨⟨⟩⟩) <;> rfl⟩
#align equiv.bool_equiv_punit_sum_punit Equiv.boolEquivPUnitSumPUnit
@[simps (config := .asFn) apply]
def sumComm (α β) : Sum α β ≃ Sum β α :=
⟨Sum.swap, Sum.swap, Sum.swap_swap, Sum.swap_swap⟩
#align equiv.sum_comm Equiv.sumComm
#align equiv.sum_comm_apply Equiv.sumComm_apply
@[simp]
theorem sumComm_symm (α β) : (sumComm α β).symm = sumComm β α :=
rfl
#align equiv.sum_comm_symm Equiv.sumComm_symm
def sumAssoc (α β γ) : Sum (Sum α β) γ ≃ Sum α (Sum β γ) :=
⟨Sum.elim (Sum.elim Sum.inl (Sum.inr ∘ Sum.inl)) (Sum.inr ∘ Sum.inr),
Sum.elim (Sum.inl ∘ Sum.inl) <| Sum.elim (Sum.inl ∘ Sum.inr) Sum.inr,
by rintro (⟨_ | _⟩ | _) <;> rfl, by
rintro (_ | ⟨_ | _⟩) <;> rfl⟩
#align equiv.sum_assoc Equiv.sumAssoc
@[simp]
theorem sumAssoc_apply_inl_inl (a) : sumAssoc α β γ (inl (inl a)) = inl a :=
rfl
#align equiv.sum_assoc_apply_inl_inl Equiv.sumAssoc_apply_inl_inl
@[simp]
theorem sumAssoc_apply_inl_inr (b) : sumAssoc α β γ (inl (inr b)) = inr (inl b) :=
rfl
#align equiv.sum_assoc_apply_inl_inr Equiv.sumAssoc_apply_inl_inr
@[simp]
theorem sumAssoc_apply_inr (c) : sumAssoc α β γ (inr c) = inr (inr c) :=
rfl
#align equiv.sum_assoc_apply_inr Equiv.sumAssoc_apply_inr
@[simp]
theorem sumAssoc_symm_apply_inl {α β γ} (a) : (sumAssoc α β γ).symm (inl a) = inl (inl a) :=
rfl
#align equiv.sum_assoc_symm_apply_inl Equiv.sumAssoc_symm_apply_inl
@[simp]
theorem sumAssoc_symm_apply_inr_inl {α β γ} (b) :
(sumAssoc α β γ).symm (inr (inl b)) = inl (inr b) :=
rfl
#align equiv.sum_assoc_symm_apply_inr_inl Equiv.sumAssoc_symm_apply_inr_inl
@[simp]
theorem sumAssoc_symm_apply_inr_inr {α β γ} (c) : (sumAssoc α β γ).symm (inr (inr c)) = inr c :=
rfl
#align equiv.sum_assoc_symm_apply_inr_inr Equiv.sumAssoc_symm_apply_inr_inr
@[simps symm_apply]
def sumEmpty (α β) [IsEmpty β] : Sum α β ≃ α where
toFun := Sum.elim id isEmptyElim
invFun := inl
left_inv s := by
rcases s with (_ | x)
· rfl
· exact isEmptyElim x
right_inv _ := rfl
#align equiv.sum_empty Equiv.sumEmpty
#align equiv.sum_empty_symm_apply Equiv.sumEmpty_symm_apply
@[simp]
theorem sumEmpty_apply_inl [IsEmpty β] (a : α) : sumEmpty α β (Sum.inl a) = a :=
rfl
#align equiv.sum_empty_apply_inl Equiv.sumEmpty_apply_inl
@[simps! symm_apply]
def emptySum (α β) [IsEmpty α] : Sum α β ≃ β :=
(sumComm _ _).trans <| sumEmpty _ _
#align equiv.empty_sum Equiv.emptySum
#align equiv.empty_sum_symm_apply Equiv.emptySum_symm_apply
@[simp]
theorem emptySum_apply_inr [IsEmpty α] (b : β) : emptySum α β (Sum.inr b) = b :=
rfl
#align equiv.empty_sum_apply_inr Equiv.emptySum_apply_inr
def optionEquivSumPUnit (α) : Option α ≃ Sum α PUnit :=
⟨fun o => o.elim (inr PUnit.unit) inl, fun s => s.elim some fun _ => none,
fun o => by cases o <;> rfl,
fun s => by rcases s with (_ | ⟨⟨⟩⟩) <;> rfl⟩
#align equiv.option_equiv_sum_punit Equiv.optionEquivSumPUnit
@[simp]
theorem optionEquivSumPUnit_none : optionEquivSumPUnit α none = Sum.inr PUnit.unit :=
rfl
#align equiv.option_equiv_sum_punit_none Equiv.optionEquivSumPUnit_none
@[simp]
theorem optionEquivSumPUnit_some (a) : optionEquivSumPUnit α (some a) = Sum.inl a :=
rfl
#align equiv.option_equiv_sum_punit_some Equiv.optionEquivSumPUnit_some
@[simp]
theorem optionEquivSumPUnit_coe (a : α) : optionEquivSumPUnit α a = Sum.inl a :=
rfl
#align equiv.option_equiv_sum_punit_coe Equiv.optionEquivSumPUnit_coe
@[simp]
theorem optionEquivSumPUnit_symm_inl (a) : (optionEquivSumPUnit α).symm (Sum.inl a) = a :=
rfl
#align equiv.option_equiv_sum_punit_symm_inl Equiv.optionEquivSumPUnit_symm_inl
@[simp]
theorem optionEquivSumPUnit_symm_inr (a) : (optionEquivSumPUnit α).symm (Sum.inr a) = none :=
rfl
#align equiv.option_equiv_sum_punit_symm_inr Equiv.optionEquivSumPUnit_symm_inr
@[simps]
def optionIsSomeEquiv (α) : { x : Option α // x.isSome } ≃ α where
toFun o := Option.get _ o.2
invFun x := ⟨some x, rfl⟩
left_inv _ := Subtype.eq <| Option.some_get _
right_inv _ := Option.get_some _ _
#align equiv.option_is_some_equiv Equiv.optionIsSomeEquiv
#align equiv.option_is_some_equiv_apply Equiv.optionIsSomeEquiv_apply
#align equiv.option_is_some_equiv_symm_apply_coe Equiv.optionIsSomeEquiv_symm_apply_coe
@[simps]
def piOptionEquivProd {β : Option α → Type*} :
(∀ a : Option α, β a) ≃ β none × ∀ a : α, β (some a) where
toFun f := (f none, fun a => f (some a))
invFun x a := Option.casesOn a x.fst x.snd
left_inv f := funext fun a => by cases a <;> rfl
right_inv x := by simp
#align equiv.pi_option_equiv_prod Equiv.piOptionEquivProd
#align equiv.pi_option_equiv_prod_symm_apply Equiv.piOptionEquivProd_symm_apply
#align equiv.pi_option_equiv_prod_apply Equiv.piOptionEquivProd_apply
def sumEquivSigmaBool (α β : Type u) : Sum α β ≃ Σ b : Bool, b.casesOn α β :=
⟨fun s => s.elim (fun x => ⟨false, x⟩) fun x => ⟨true, x⟩, fun s =>
match s with
| ⟨false, a⟩ => inl a
| ⟨true, b⟩ => inr b,
fun s => by cases s <;> rfl, fun s => by rcases s with ⟨_ | _, _⟩ <;> rfl⟩
#align equiv.sum_equiv_sigma_bool Equiv.sumEquivSigmaBool
-- See also `Equiv.sigmaPreimageEquiv`.
@[simps]
def sigmaFiberEquiv {α β : Type*} (f : α → β) : (Σ y : β, { x // f x = y }) ≃ α :=
⟨fun x => ↑x.2, fun x => ⟨f x, x, rfl⟩, fun ⟨_, _, rfl⟩ => rfl, fun _ => rfl⟩
#align equiv.sigma_fiber_equiv Equiv.sigmaFiberEquiv
#align equiv.sigma_fiber_equiv_apply Equiv.sigmaFiberEquiv_apply
#align equiv.sigma_fiber_equiv_symm_apply_fst Equiv.sigmaFiberEquiv_symm_apply_fst
#align equiv.sigma_fiber_equiv_symm_apply_snd_coe Equiv.sigmaFiberEquiv_symm_apply_snd_coe
def sigmaEquivOptionOfInhabited (α : Type u) [Inhabited α] [DecidableEq α] :
Σ β : Type u, α ≃ Option β where
fst := {a // a ≠ default}
snd.toFun a := if h : a = default then none else some ⟨a, h⟩
snd.invFun := Option.elim' default (↑)
snd.left_inv a := by dsimp only; split_ifs <;> simp [*]
snd.right_inv
| none => by simp
| some ⟨a, ha⟩ => dif_neg ha
#align equiv.sigma_equiv_option_of_inhabited Equiv.sigmaEquivOptionOfInhabited
end
section sumCompl
def sumCompl {α : Type*} (p : α → Prop) [DecidablePred p] :
Sum { a // p a } { a // ¬p a } ≃ α where
toFun := Sum.elim Subtype.val Subtype.val
invFun a := if h : p a then Sum.inl ⟨a, h⟩ else Sum.inr ⟨a, h⟩
left_inv := by
rintro (⟨x, hx⟩ | ⟨x, hx⟩) <;> dsimp
· rw [dif_pos]
· rw [dif_neg]
right_inv a := by
dsimp
split_ifs <;> rfl
#align equiv.sum_compl Equiv.sumCompl
@[simp]
theorem sumCompl_apply_inl (p : α → Prop) [DecidablePred p] (x : { a // p a }) :
sumCompl p (Sum.inl x) = x :=
rfl
#align equiv.sum_compl_apply_inl Equiv.sumCompl_apply_inl
@[simp]
theorem sumCompl_apply_inr (p : α → Prop) [DecidablePred p] (x : { a // ¬p a }) :
sumCompl p (Sum.inr x) = x :=
rfl
#align equiv.sum_compl_apply_inr Equiv.sumCompl_apply_inr
@[simp]
theorem sumCompl_apply_symm_of_pos (p : α → Prop) [DecidablePred p] (a : α) (h : p a) :
(sumCompl p).symm a = Sum.inl ⟨a, h⟩ :=
dif_pos h
#align equiv.sum_compl_apply_symm_of_pos Equiv.sumCompl_apply_symm_of_pos
@[simp]
theorem sumCompl_apply_symm_of_neg (p : α → Prop) [DecidablePred p] (a : α) (h : ¬p a) :
(sumCompl p).symm a = Sum.inr ⟨a, h⟩ :=
dif_neg h
#align equiv.sum_compl_apply_symm_of_neg Equiv.sumCompl_apply_symm_of_neg
def subtypeCongr {p q : α → Prop} [DecidablePred p] [DecidablePred q]
(e : { x // p x } ≃ { x // q x }) (f : { x // ¬p x } ≃ { x // ¬q x }) : Perm α :=
(sumCompl p).symm.trans ((sumCongr e f).trans (sumCompl q))
#align equiv.subtype_congr Equiv.subtypeCongr
variable {p : ε → Prop} [DecidablePred p]
variable (ep ep' : Perm { a // p a }) (en en' : Perm { a // ¬p a })
def Perm.subtypeCongr : Equiv.Perm ε :=
permCongr (sumCompl p) (sumCongr ep en)
#align equiv.perm.subtype_congr Equiv.Perm.subtypeCongr
theorem Perm.subtypeCongr.apply (a : ε) : ep.subtypeCongr en a =
if h : p a then (ep ⟨a, h⟩ : ε) else en ⟨a, h⟩ := by
by_cases h : p a <;> simp [Perm.subtypeCongr, h]
#align equiv.perm.subtype_congr.apply Equiv.Perm.subtypeCongr.apply
@[simp]
| Mathlib/Logic/Equiv/Basic.lean | 632 | 633 | theorem Perm.subtypeCongr.left_apply {a : ε} (h : p a) : ep.subtypeCongr en a = ep ⟨a, h⟩ := by |
simp [Perm.subtypeCongr.apply, h]
|
import Mathlib.Probability.Variance
#align_import probability.moments from "leanprover-community/mathlib"@"85453a2a14be8da64caf15ca50930cf4c6e5d8de"
open MeasureTheory Filter Finset Real
noncomputable section
open scoped MeasureTheory ProbabilityTheory ENNReal NNReal
namespace ProbabilityTheory
variable {Ω ι : Type*} {m : MeasurableSpace Ω} {X : Ω → ℝ} {p : ℕ} {μ : Measure Ω}
def moment (X : Ω → ℝ) (p : ℕ) (μ : Measure Ω) : ℝ :=
μ[X ^ p]
#align probability_theory.moment ProbabilityTheory.moment
def centralMoment (X : Ω → ℝ) (p : ℕ) (μ : Measure Ω) : ℝ := by
have m := fun (x : Ω) => μ[X] -- Porting note: Lean deems `μ[(X - fun x => μ[X]) ^ p]` ambiguous
exact μ[(X - m) ^ p]
#align probability_theory.central_moment ProbabilityTheory.centralMoment
@[simp]
theorem moment_zero (hp : p ≠ 0) : moment 0 p μ = 0 := by
simp only [moment, hp, zero_pow, Ne, not_false_iff, Pi.zero_apply, integral_const,
smul_eq_mul, mul_zero, integral_zero]
#align probability_theory.moment_zero ProbabilityTheory.moment_zero
@[simp]
theorem centralMoment_zero (hp : p ≠ 0) : centralMoment 0 p μ = 0 := by
simp only [centralMoment, hp, Pi.zero_apply, integral_const, smul_eq_mul,
mul_zero, zero_sub, Pi.pow_apply, Pi.neg_apply, neg_zero, zero_pow, Ne, not_false_iff]
#align probability_theory.central_moment_zero ProbabilityTheory.centralMoment_zero
theorem centralMoment_one' [IsFiniteMeasure μ] (h_int : Integrable X μ) :
centralMoment X 1 μ = (1 - (μ Set.univ).toReal) * μ[X] := by
simp only [centralMoment, Pi.sub_apply, pow_one]
rw [integral_sub h_int (integrable_const _)]
simp only [sub_mul, integral_const, smul_eq_mul, one_mul]
#align probability_theory.central_moment_one' ProbabilityTheory.centralMoment_one'
@[simp]
theorem centralMoment_one [IsProbabilityMeasure μ] : centralMoment X 1 μ = 0 := by
by_cases h_int : Integrable X μ
· rw [centralMoment_one' h_int]
simp only [measure_univ, ENNReal.one_toReal, sub_self, zero_mul]
· simp only [centralMoment, Pi.sub_apply, pow_one]
have : ¬Integrable (fun x => X x - integral μ X) μ := by
refine fun h_sub => h_int ?_
have h_add : X = (fun x => X x - integral μ X) + fun _ => integral μ X := by ext1 x; simp
rw [h_add]
exact h_sub.add (integrable_const _)
rw [integral_undef this]
#align probability_theory.central_moment_one ProbabilityTheory.centralMoment_one
theorem centralMoment_two_eq_variance [IsFiniteMeasure μ] (hX : Memℒp X 2 μ) :
centralMoment X 2 μ = variance X μ := by rw [hX.variance_eq]; rfl
#align probability_theory.central_moment_two_eq_variance ProbabilityTheory.centralMoment_two_eq_variance
section MomentGeneratingFunction
variable {t : ℝ}
def mgf (X : Ω → ℝ) (μ : Measure Ω) (t : ℝ) : ℝ :=
μ[fun ω => exp (t * X ω)]
#align probability_theory.mgf ProbabilityTheory.mgf
def cgf (X : Ω → ℝ) (μ : Measure Ω) (t : ℝ) : ℝ :=
log (mgf X μ t)
#align probability_theory.cgf ProbabilityTheory.cgf
@[simp]
theorem mgf_zero_fun : mgf 0 μ t = (μ Set.univ).toReal := by
simp only [mgf, Pi.zero_apply, mul_zero, exp_zero, integral_const, smul_eq_mul, mul_one]
#align probability_theory.mgf_zero_fun ProbabilityTheory.mgf_zero_fun
@[simp]
theorem cgf_zero_fun : cgf 0 μ t = log (μ Set.univ).toReal := by simp only [cgf, mgf_zero_fun]
#align probability_theory.cgf_zero_fun ProbabilityTheory.cgf_zero_fun
@[simp]
theorem mgf_zero_measure : mgf X (0 : Measure Ω) t = 0 := by simp only [mgf, integral_zero_measure]
#align probability_theory.mgf_zero_measure ProbabilityTheory.mgf_zero_measure
@[simp]
theorem cgf_zero_measure : cgf X (0 : Measure Ω) t = 0 := by
simp only [cgf, log_zero, mgf_zero_measure]
#align probability_theory.cgf_zero_measure ProbabilityTheory.cgf_zero_measure
@[simp]
theorem mgf_const' (c : ℝ) : mgf (fun _ => c) μ t = (μ Set.univ).toReal * exp (t * c) := by
simp only [mgf, integral_const, smul_eq_mul]
#align probability_theory.mgf_const' ProbabilityTheory.mgf_const'
-- @[simp] -- Porting note: `simp only` already proves this
theorem mgf_const (c : ℝ) [IsProbabilityMeasure μ] : mgf (fun _ => c) μ t = exp (t * c) := by
simp only [mgf_const', measure_univ, ENNReal.one_toReal, one_mul]
#align probability_theory.mgf_const ProbabilityTheory.mgf_const
@[simp]
theorem cgf_const' [IsFiniteMeasure μ] (hμ : μ ≠ 0) (c : ℝ) :
cgf (fun _ => c) μ t = log (μ Set.univ).toReal + t * c := by
simp only [cgf, mgf_const']
rw [log_mul _ (exp_pos _).ne']
· rw [log_exp _]
· rw [Ne, ENNReal.toReal_eq_zero_iff, Measure.measure_univ_eq_zero]
simp only [hμ, measure_ne_top μ Set.univ, or_self_iff, not_false_iff]
#align probability_theory.cgf_const' ProbabilityTheory.cgf_const'
@[simp]
theorem cgf_const [IsProbabilityMeasure μ] (c : ℝ) : cgf (fun _ => c) μ t = t * c := by
simp only [cgf, mgf_const, log_exp]
#align probability_theory.cgf_const ProbabilityTheory.cgf_const
@[simp]
theorem mgf_zero' : mgf X μ 0 = (μ Set.univ).toReal := by
simp only [mgf, zero_mul, exp_zero, integral_const, smul_eq_mul, mul_one]
#align probability_theory.mgf_zero' ProbabilityTheory.mgf_zero'
-- @[simp] -- Porting note: `simp only` already proves this
theorem mgf_zero [IsProbabilityMeasure μ] : mgf X μ 0 = 1 := by
simp only [mgf_zero', measure_univ, ENNReal.one_toReal]
#align probability_theory.mgf_zero ProbabilityTheory.mgf_zero
@[simp]
theorem cgf_zero' : cgf X μ 0 = log (μ Set.univ).toReal := by simp only [cgf, mgf_zero']
#align probability_theory.cgf_zero' ProbabilityTheory.cgf_zero'
-- @[simp] -- Porting note: `simp only` already proves this
theorem cgf_zero [IsProbabilityMeasure μ] : cgf X μ 0 = 0 := by
simp only [cgf_zero', measure_univ, ENNReal.one_toReal, log_one]
#align probability_theory.cgf_zero ProbabilityTheory.cgf_zero
theorem mgf_undef (hX : ¬Integrable (fun ω => exp (t * X ω)) μ) : mgf X μ t = 0 := by
simp only [mgf, integral_undef hX]
#align probability_theory.mgf_undef ProbabilityTheory.mgf_undef
theorem cgf_undef (hX : ¬Integrable (fun ω => exp (t * X ω)) μ) : cgf X μ t = 0 := by
simp only [cgf, mgf_undef hX, log_zero]
#align probability_theory.cgf_undef ProbabilityTheory.cgf_undef
theorem mgf_nonneg : 0 ≤ mgf X μ t := by
unfold mgf; positivity
#align probability_theory.mgf_nonneg ProbabilityTheory.mgf_nonneg
theorem mgf_pos' (hμ : μ ≠ 0) (h_int_X : Integrable (fun ω => exp (t * X ω)) μ) :
0 < mgf X μ t := by
simp_rw [mgf]
have : ∫ x : Ω, exp (t * X x) ∂μ = ∫ x : Ω in Set.univ, exp (t * X x) ∂μ := by
simp only [Measure.restrict_univ]
rw [this, setIntegral_pos_iff_support_of_nonneg_ae _ _]
· have h_eq_univ : (Function.support fun x : Ω => exp (t * X x)) = Set.univ := by
ext1 x
simp only [Function.mem_support, Set.mem_univ, iff_true_iff]
exact (exp_pos _).ne'
rw [h_eq_univ, Set.inter_univ _]
refine Ne.bot_lt ?_
simp only [hμ, ENNReal.bot_eq_zero, Ne, Measure.measure_univ_eq_zero, not_false_iff]
· filter_upwards with x
rw [Pi.zero_apply]
exact (exp_pos _).le
· rwa [integrableOn_univ]
#align probability_theory.mgf_pos' ProbabilityTheory.mgf_pos'
theorem mgf_pos [IsProbabilityMeasure μ] (h_int_X : Integrable (fun ω => exp (t * X ω)) μ) :
0 < mgf X μ t :=
mgf_pos' (IsProbabilityMeasure.ne_zero μ) h_int_X
#align probability_theory.mgf_pos ProbabilityTheory.mgf_pos
theorem mgf_neg : mgf (-X) μ t = mgf X μ (-t) := by simp_rw [mgf, Pi.neg_apply, mul_neg, neg_mul]
#align probability_theory.mgf_neg ProbabilityTheory.mgf_neg
theorem cgf_neg : cgf (-X) μ t = cgf X μ (-t) := by simp_rw [cgf, mgf_neg]
#align probability_theory.cgf_neg ProbabilityTheory.cgf_neg
theorem IndepFun.exp_mul {X Y : Ω → ℝ} (h_indep : IndepFun X Y μ) (s t : ℝ) :
IndepFun (fun ω => exp (s * X ω)) (fun ω => exp (t * Y ω)) μ := by
have h_meas : ∀ t, Measurable fun x => exp (t * x) := fun t => (measurable_id'.const_mul t).exp
change IndepFun ((fun x => exp (s * x)) ∘ X) ((fun x => exp (t * x)) ∘ Y) μ
exact IndepFun.comp h_indep (h_meas s) (h_meas t)
#align probability_theory.indep_fun.exp_mul ProbabilityTheory.IndepFun.exp_mul
theorem IndepFun.mgf_add {X Y : Ω → ℝ} (h_indep : IndepFun X Y μ)
(hX : AEStronglyMeasurable (fun ω => exp (t * X ω)) μ)
(hY : AEStronglyMeasurable (fun ω => exp (t * Y ω)) μ) :
mgf (X + Y) μ t = mgf X μ t * mgf Y μ t := by
simp_rw [mgf, Pi.add_apply, mul_add, exp_add]
exact (h_indep.exp_mul t t).integral_mul hX hY
#align probability_theory.indep_fun.mgf_add ProbabilityTheory.IndepFun.mgf_add
theorem IndepFun.mgf_add' {X Y : Ω → ℝ} (h_indep : IndepFun X Y μ) (hX : AEStronglyMeasurable X μ)
(hY : AEStronglyMeasurable Y μ) : mgf (X + Y) μ t = mgf X μ t * mgf Y μ t := by
have A : Continuous fun x : ℝ => exp (t * x) := by fun_prop
have h'X : AEStronglyMeasurable (fun ω => exp (t * X ω)) μ :=
A.aestronglyMeasurable.comp_aemeasurable hX.aemeasurable
have h'Y : AEStronglyMeasurable (fun ω => exp (t * Y ω)) μ :=
A.aestronglyMeasurable.comp_aemeasurable hY.aemeasurable
exact h_indep.mgf_add h'X h'Y
#align probability_theory.indep_fun.mgf_add' ProbabilityTheory.IndepFun.mgf_add'
theorem IndepFun.cgf_add {X Y : Ω → ℝ} (h_indep : IndepFun X Y μ)
(h_int_X : Integrable (fun ω => exp (t * X ω)) μ)
(h_int_Y : Integrable (fun ω => exp (t * Y ω)) μ) :
cgf (X + Y) μ t = cgf X μ t + cgf Y μ t := by
by_cases hμ : μ = 0
· simp [hμ]
simp only [cgf, h_indep.mgf_add h_int_X.aestronglyMeasurable h_int_Y.aestronglyMeasurable]
exact log_mul (mgf_pos' hμ h_int_X).ne' (mgf_pos' hμ h_int_Y).ne'
#align probability_theory.indep_fun.cgf_add ProbabilityTheory.IndepFun.cgf_add
theorem aestronglyMeasurable_exp_mul_add {X Y : Ω → ℝ}
(h_int_X : AEStronglyMeasurable (fun ω => exp (t * X ω)) μ)
(h_int_Y : AEStronglyMeasurable (fun ω => exp (t * Y ω)) μ) :
AEStronglyMeasurable (fun ω => exp (t * (X + Y) ω)) μ := by
simp_rw [Pi.add_apply, mul_add, exp_add]
exact AEStronglyMeasurable.mul h_int_X h_int_Y
#align probability_theory.ae_strongly_measurable_exp_mul_add ProbabilityTheory.aestronglyMeasurable_exp_mul_add
theorem aestronglyMeasurable_exp_mul_sum {X : ι → Ω → ℝ} {s : Finset ι}
(h_int : ∀ i ∈ s, AEStronglyMeasurable (fun ω => exp (t * X i ω)) μ) :
AEStronglyMeasurable (fun ω => exp (t * (∑ i ∈ s, X i) ω)) μ := by
classical
induction' s using Finset.induction_on with i s hi_notin_s h_rec h_int
· simp only [Pi.zero_apply, sum_apply, sum_empty, mul_zero, exp_zero]
exact aestronglyMeasurable_const
· have : ∀ i : ι, i ∈ s → AEStronglyMeasurable (fun ω : Ω => exp (t * X i ω)) μ := fun i hi =>
h_int i (mem_insert_of_mem hi)
specialize h_rec this
rw [sum_insert hi_notin_s]
apply aestronglyMeasurable_exp_mul_add (h_int i (mem_insert_self _ _)) h_rec
#align probability_theory.ae_strongly_measurable_exp_mul_sum ProbabilityTheory.aestronglyMeasurable_exp_mul_sum
| Mathlib/Probability/Moments.lean | 274 | 279 | theorem IndepFun.integrable_exp_mul_add {X Y : Ω → ℝ} (h_indep : IndepFun X Y μ)
(h_int_X : Integrable (fun ω => exp (t * X ω)) μ)
(h_int_Y : Integrable (fun ω => exp (t * Y ω)) μ) :
Integrable (fun ω => exp (t * (X + Y) ω)) μ := by |
simp_rw [Pi.add_apply, mul_add, exp_add]
exact (h_indep.exp_mul t t).integrable_mul h_int_X h_int_Y
|
import Mathlib.Analysis.InnerProductSpace.Dual
import Mathlib.Analysis.InnerProductSpace.PiL2
#align_import analysis.inner_product_space.adjoint from "leanprover-community/mathlib"@"46b633fd842bef9469441c0209906f6dddd2b4f5"
noncomputable section
open RCLike
open scoped ComplexConjugate
variable {𝕜 E F G : Type*} [RCLike 𝕜]
variable [NormedAddCommGroup E] [NormedAddCommGroup F] [NormedAddCommGroup G]
variable [InnerProductSpace 𝕜 E] [InnerProductSpace 𝕜 F] [InnerProductSpace 𝕜 G]
local notation "⟪" x ", " y "⟫" => @inner 𝕜 _ _ x y
open InnerProductSpace
namespace ContinuousLinearMap
variable [CompleteSpace E] [CompleteSpace G]
-- Note: made noncomputable to stop excess compilation
-- leanprover-community/mathlib4#7103
noncomputable def adjointAux : (E →L[𝕜] F) →L⋆[𝕜] F →L[𝕜] E :=
(ContinuousLinearMap.compSL _ _ _ _ _ ((toDual 𝕜 E).symm : NormedSpace.Dual 𝕜 E →L⋆[𝕜] E)).comp
(toSesqForm : (E →L[𝕜] F) →L[𝕜] F →L⋆[𝕜] NormedSpace.Dual 𝕜 E)
#align continuous_linear_map.adjoint_aux ContinuousLinearMap.adjointAux
@[simp]
theorem adjointAux_apply (A : E →L[𝕜] F) (x : F) :
adjointAux A x = ((toDual 𝕜 E).symm : NormedSpace.Dual 𝕜 E → E) ((toSesqForm A) x) :=
rfl
#align continuous_linear_map.adjoint_aux_apply ContinuousLinearMap.adjointAux_apply
theorem adjointAux_inner_left (A : E →L[𝕜] F) (x : E) (y : F) : ⟪adjointAux A y, x⟫ = ⟪y, A x⟫ := by
rw [adjointAux_apply, toDual_symm_apply, toSesqForm_apply_coe, coe_comp', innerSL_apply_coe,
Function.comp_apply]
#align continuous_linear_map.adjoint_aux_inner_left ContinuousLinearMap.adjointAux_inner_left
theorem adjointAux_inner_right (A : E →L[𝕜] F) (x : E) (y : F) :
⟪x, adjointAux A y⟫ = ⟪A x, y⟫ := by
rw [← inner_conj_symm, adjointAux_inner_left, inner_conj_symm]
#align continuous_linear_map.adjoint_aux_inner_right ContinuousLinearMap.adjointAux_inner_right
variable [CompleteSpace F]
theorem adjointAux_adjointAux (A : E →L[𝕜] F) : adjointAux (adjointAux A) = A := by
ext v
refine ext_inner_left 𝕜 fun w => ?_
rw [adjointAux_inner_right, adjointAux_inner_left]
#align continuous_linear_map.adjoint_aux_adjoint_aux ContinuousLinearMap.adjointAux_adjointAux
@[simp]
theorem adjointAux_norm (A : E →L[𝕜] F) : ‖adjointAux A‖ = ‖A‖ := by
refine le_antisymm ?_ ?_
· refine ContinuousLinearMap.opNorm_le_bound _ (norm_nonneg _) fun x => ?_
rw [adjointAux_apply, LinearIsometryEquiv.norm_map]
exact toSesqForm_apply_norm_le
· nth_rw 1 [← adjointAux_adjointAux A]
refine ContinuousLinearMap.opNorm_le_bound _ (norm_nonneg _) fun x => ?_
rw [adjointAux_apply, LinearIsometryEquiv.norm_map]
exact toSesqForm_apply_norm_le
#align continuous_linear_map.adjoint_aux_norm ContinuousLinearMap.adjointAux_norm
def adjoint : (E →L[𝕜] F) ≃ₗᵢ⋆[𝕜] F →L[𝕜] E :=
LinearIsometryEquiv.ofSurjective { adjointAux with norm_map' := adjointAux_norm } fun A =>
⟨adjointAux A, adjointAux_adjointAux A⟩
#align continuous_linear_map.adjoint ContinuousLinearMap.adjoint
scoped[InnerProduct] postfix:1000 "†" => ContinuousLinearMap.adjoint
open InnerProduct
theorem adjoint_inner_left (A : E →L[𝕜] F) (x : E) (y : F) : ⟪(A†) y, x⟫ = ⟪y, A x⟫ :=
adjointAux_inner_left A x y
#align continuous_linear_map.adjoint_inner_left ContinuousLinearMap.adjoint_inner_left
theorem adjoint_inner_right (A : E →L[𝕜] F) (x : E) (y : F) : ⟪x, (A†) y⟫ = ⟪A x, y⟫ :=
adjointAux_inner_right A x y
#align continuous_linear_map.adjoint_inner_right ContinuousLinearMap.adjoint_inner_right
@[simp]
theorem adjoint_adjoint (A : E →L[𝕜] F) : A†† = A :=
adjointAux_adjointAux A
#align continuous_linear_map.adjoint_adjoint ContinuousLinearMap.adjoint_adjoint
@[simp]
theorem adjoint_comp (A : F →L[𝕜] G) (B : E →L[𝕜] F) : (A ∘L B)† = B† ∘L A† := by
ext v
refine ext_inner_left 𝕜 fun w => ?_
simp only [adjoint_inner_right, ContinuousLinearMap.coe_comp', Function.comp_apply]
#align continuous_linear_map.adjoint_comp ContinuousLinearMap.adjoint_comp
theorem apply_norm_sq_eq_inner_adjoint_left (A : E →L[𝕜] F) (x : E) :
‖A x‖ ^ 2 = re ⟪(A† ∘L A) x, x⟫ := by
have h : ⟪(A† ∘L A) x, x⟫ = ⟪A x, A x⟫ := by rw [← adjoint_inner_left]; rfl
rw [h, ← inner_self_eq_norm_sq (𝕜 := 𝕜) _]
#align continuous_linear_map.apply_norm_sq_eq_inner_adjoint_left ContinuousLinearMap.apply_norm_sq_eq_inner_adjoint_left
theorem apply_norm_eq_sqrt_inner_adjoint_left (A : E →L[𝕜] F) (x : E) :
‖A x‖ = √(re ⟪(A† ∘L A) x, x⟫) := by
rw [← apply_norm_sq_eq_inner_adjoint_left, Real.sqrt_sq (norm_nonneg _)]
#align continuous_linear_map.apply_norm_eq_sqrt_inner_adjoint_left ContinuousLinearMap.apply_norm_eq_sqrt_inner_adjoint_left
theorem apply_norm_sq_eq_inner_adjoint_right (A : E →L[𝕜] F) (x : E) :
‖A x‖ ^ 2 = re ⟪x, (A† ∘L A) x⟫ := by
have h : ⟪x, (A† ∘L A) x⟫ = ⟪A x, A x⟫ := by rw [← adjoint_inner_right]; rfl
rw [h, ← inner_self_eq_norm_sq (𝕜 := 𝕜) _]
#align continuous_linear_map.apply_norm_sq_eq_inner_adjoint_right ContinuousLinearMap.apply_norm_sq_eq_inner_adjoint_right
theorem apply_norm_eq_sqrt_inner_adjoint_right (A : E →L[𝕜] F) (x : E) :
‖A x‖ = √(re ⟪x, (A† ∘L A) x⟫) := by
rw [← apply_norm_sq_eq_inner_adjoint_right, Real.sqrt_sq (norm_nonneg _)]
#align continuous_linear_map.apply_norm_eq_sqrt_inner_adjoint_right ContinuousLinearMap.apply_norm_eq_sqrt_inner_adjoint_right
theorem eq_adjoint_iff (A : E →L[𝕜] F) (B : F →L[𝕜] E) : A = B† ↔ ∀ x y, ⟪A x, y⟫ = ⟪x, B y⟫ := by
refine ⟨fun h x y => by rw [h, adjoint_inner_left], fun h => ?_⟩
ext x
exact ext_inner_right 𝕜 fun y => by simp only [adjoint_inner_left, h x y]
#align continuous_linear_map.eq_adjoint_iff ContinuousLinearMap.eq_adjoint_iff
@[simp]
| Mathlib/Analysis/InnerProductSpace/Adjoint.lean | 175 | 179 | theorem adjoint_id :
ContinuousLinearMap.adjoint (ContinuousLinearMap.id 𝕜 E) = ContinuousLinearMap.id 𝕜 E := by |
refine Eq.symm ?_
rw [eq_adjoint_iff]
simp
|
import Mathlib.Probability.Notation
import Mathlib.Probability.Density
import Mathlib.Probability.ConditionalProbability
import Mathlib.Probability.ProbabilityMassFunction.Constructions
open scoped Classical MeasureTheory NNReal ENNReal
-- TODO: We can't `open ProbabilityTheory` without opening the `ProbabilityTheory` locale :(
open TopologicalSpace MeasureTheory.Measure PMF
noncomputable section
namespace MeasureTheory
variable {E : Type*} [MeasurableSpace E] {m : Measure E} {μ : Measure E}
namespace pdf
variable {Ω : Type*}
variable {_ : MeasurableSpace Ω} {ℙ : Measure Ω}
def IsUniform (X : Ω → E) (s : Set E) (ℙ : Measure Ω) (μ : Measure E := by volume_tac) :=
map X ℙ = ProbabilityTheory.cond μ s
#align measure_theory.pdf.is_uniform MeasureTheory.pdf.IsUniform
namespace IsUniform
theorem aemeasurable {X : Ω → E} {s : Set E} (hns : μ s ≠ 0) (hnt : μ s ≠ ∞)
(hu : IsUniform X s ℙ μ) : AEMeasurable X ℙ := by
dsimp [IsUniform, ProbabilityTheory.cond] at hu
by_contra h
rw [map_of_not_aemeasurable h] at hu
apply zero_ne_one' ℝ≥0∞
calc
0 = (0 : Measure E) Set.univ := rfl
_ = _ := by rw [hu, smul_apply, restrict_apply MeasurableSet.univ,
Set.univ_inter, smul_eq_mul, ENNReal.inv_mul_cancel hns hnt]
theorem absolutelyContinuous {X : Ω → E} {s : Set E} (hu : IsUniform X s ℙ μ) : map X ℙ ≪ μ := by
rw [hu]; exact ProbabilityTheory.cond_absolutelyContinuous
theorem measure_preimage {X : Ω → E} {s : Set E} (hns : μ s ≠ 0) (hnt : μ s ≠ ∞)
(hu : IsUniform X s ℙ μ) {A : Set E} (hA : MeasurableSet A) :
ℙ (X ⁻¹' A) = μ (s ∩ A) / μ s := by
rwa [← map_apply_of_aemeasurable (hu.aemeasurable hns hnt) hA, hu, ProbabilityTheory.cond_apply',
ENNReal.div_eq_inv_mul]
#align measure_theory.pdf.is_uniform.measure_preimage MeasureTheory.pdf.IsUniform.measure_preimage
theorem isProbabilityMeasure {X : Ω → E} {s : Set E} (hns : μ s ≠ 0) (hnt : μ s ≠ ∞)
(hu : IsUniform X s ℙ μ) : IsProbabilityMeasure ℙ :=
⟨by
have : X ⁻¹' Set.univ = Set.univ := Set.preimage_univ
rw [← this, hu.measure_preimage hns hnt MeasurableSet.univ, Set.inter_univ,
ENNReal.div_self hns hnt]⟩
#align measure_theory.pdf.is_uniform.is_probability_measure MeasureTheory.pdf.IsUniform.isProbabilityMeasure
theorem toMeasurable_iff {X : Ω → E} {s : Set E} :
IsUniform X (toMeasurable μ s) ℙ μ ↔ IsUniform X s ℙ μ := by
unfold IsUniform
rw [ProbabilityTheory.cond_toMeasurable_eq]
protected theorem toMeasurable {X : Ω → E} {s : Set E} (hu : IsUniform X s ℙ μ) :
IsUniform X (toMeasurable μ s) ℙ μ := by
unfold IsUniform at *
rwa [ProbabilityTheory.cond_toMeasurable_eq]
theorem hasPDF {X : Ω → E} {s : Set E} (hns : μ s ≠ 0) (hnt : μ s ≠ ∞)
(hu : IsUniform X s ℙ μ) : HasPDF X ℙ μ := by
let t := toMeasurable μ s
apply hasPDF_of_map_eq_withDensity (hu.aemeasurable hns hnt) (t.indicator ((μ t)⁻¹ • 1)) <|
(measurable_one.aemeasurable.const_smul (μ t)⁻¹).indicator (measurableSet_toMeasurable μ s)
rw [hu, withDensity_indicator (measurableSet_toMeasurable μ s), withDensity_smul _ measurable_one,
withDensity_one, restrict_toMeasurable hnt, measure_toMeasurable, ProbabilityTheory.cond]
#align measure_theory.pdf.is_uniform.has_pdf MeasureTheory.pdf.IsUniform.hasPDF
| Mathlib/Probability/Distributions/Uniform.lean | 114 | 121 | theorem pdf_eq_zero_of_measure_eq_zero_or_top {X : Ω → E} {s : Set E}
(hu : IsUniform X s ℙ μ) (hμs : μ s = 0 ∨ μ s = ∞) : pdf X ℙ μ =ᵐ[μ] 0 := by |
rcases hμs with H|H
· simp only [IsUniform, ProbabilityTheory.cond, H, ENNReal.inv_zero, restrict_eq_zero.mpr H,
smul_zero] at hu
simp [pdf, hu]
· simp only [IsUniform, ProbabilityTheory.cond, H, ENNReal.inv_top, zero_smul] at hu
simp [pdf, hu]
|
import Mathlib.MeasureTheory.Function.AEEqFun.DomAct
import Mathlib.MeasureTheory.Function.LpSpace
set_option autoImplicit true
open MeasureTheory Filter
open scoped ENNReal
namespace DomMulAct
variable {M N α E : Type*} [MeasurableSpace M] [MeasurableSpace N]
[MeasurableSpace α] [NormedAddCommGroup E] {μ : MeasureTheory.Measure α} {p : ℝ≥0∞}
section SMul
variable [SMul M α] [SMulInvariantMeasure M α μ] [MeasurableSMul M α]
@[to_additive]
instance : SMul Mᵈᵐᵃ (Lp E p μ) where
smul c f := Lp.compMeasurePreserving (mk.symm c • ·) (measurePreserving_smul _ _) f
@[to_additive (attr := simp)]
theorem smul_Lp_val (c : Mᵈᵐᵃ) (f : Lp E p μ) : (c • f).1 = c • f.1 := rfl
@[to_additive]
theorem smul_Lp_ae_eq (c : Mᵈᵐᵃ) (f : Lp E p μ) : c • f =ᵐ[μ] (f <| mk.symm c • ·) :=
Lp.coeFn_compMeasurePreserving _ _
@[to_additive]
theorem mk_smul_toLp (c : M) {f : α → E} (hf : Memℒp f p μ) :
mk c • hf.toLp f =
(hf.comp_measurePreserving <| measurePreserving_smul c μ).toLp (f <| c • ·) :=
rfl
@[to_additive (attr := simp)]
theorem smul_Lp_const [IsFiniteMeasure μ] (c : Mᵈᵐᵃ) (a : E) :
c • Lp.const p μ a = Lp.const p μ a :=
rfl
instance [SMul N α] [SMulCommClass M N α] [SMulInvariantMeasure N α μ] [MeasurableSMul N α] :
SMulCommClass Mᵈᵐᵃ Nᵈᵐᵃ (Lp E p μ) :=
Subtype.val_injective.smulCommClass (fun _ _ ↦ rfl) fun _ _ ↦ rfl
instance [NormedRing 𝕜] [Module 𝕜 E] [BoundedSMul 𝕜 E] : SMulCommClass Mᵈᵐᵃ 𝕜 (Lp E p μ) :=
Subtype.val_injective.smulCommClass (fun _ _ ↦ rfl) fun _ _ ↦ rfl
instance [NormedRing 𝕜] [Module 𝕜 E] [BoundedSMul 𝕜 E] : SMulCommClass 𝕜 Mᵈᵐᵃ (Lp E p μ) :=
.symm _ _ _
-- We don't have a typeclass for additive versions of the next few lemmas
-- Should we add `AddDistribAddAction` with `to_additive` both from `MulDistribMulAction`
-- and `DistribMulAction`?
@[to_additive]
theorem smul_Lp_add (c : Mᵈᵐᵃ) : ∀ f g : Lp E p μ, c • (f + g) = c • f + c • g := by
rintro ⟨⟨⟩, _⟩ ⟨⟨⟩, _⟩; rfl
attribute [simp] DomAddAct.vadd_Lp_add
@[to_additive (attr := simp 1001)]
theorem smul_Lp_zero (c : Mᵈᵐᵃ) : c • (0 : Lp E p μ) = 0 := rfl
@[to_additive]
theorem smul_Lp_neg (c : Mᵈᵐᵃ) (f : Lp E p μ) : c • (-f) = -(c • f) := by
rcases f with ⟨⟨_⟩, _⟩; rfl
@[to_additive]
theorem smul_Lp_sub (c : Mᵈᵐᵃ) : ∀ f g : Lp E p μ, c • (f - g) = c • f - c • g := by
rintro ⟨⟨⟩, _⟩ ⟨⟨⟩, _⟩; rfl
instance : DistribSMul Mᵈᵐᵃ (Lp E p μ) where
smul_zero _ := rfl
smul_add := by rintro _ ⟨⟨⟩, _⟩ ⟨⟨⟩, _⟩; rfl
-- The next few lemmas follow from the `IsometricSMul` instance if `1 ≤ p`
@[to_additive (attr := simp)]
theorem norm_smul_Lp (c : Mᵈᵐᵃ) (f : Lp E p μ) : ‖c • f‖ = ‖f‖ :=
Lp.norm_compMeasurePreserving _ _
@[to_additive (attr := simp)]
theorem nnnorm_smul_Lp (c : Mᵈᵐᵃ) (f : Lp E p μ) : ‖c • f‖₊ = ‖f‖₊ :=
NNReal.eq <| Lp.norm_compMeasurePreserving _ _
@[to_additive (attr := simp)]
theorem dist_smul_Lp (c : Mᵈᵐᵃ) (f g : Lp E p μ) : dist (c • f) (c • g) = dist f g := by
simp only [dist, ← smul_Lp_sub, norm_smul_Lp]
@[to_additive (attr := simp)]
| Mathlib/MeasureTheory/Function/LpSpace/DomAct/Basic.lean | 103 | 104 | theorem edist_smul_Lp (c : Mᵈᵐᵃ) (f g : Lp E p μ) : edist (c • f) (c • g) = edist f g := by |
simp only [Lp.edist_dist, dist_smul_Lp]
|
import Mathlib.RingTheory.DedekindDomain.Ideal
import Mathlib.RingTheory.IsAdjoinRoot
#align_import number_theory.kummer_dedekind from "leanprover-community/mathlib"@"65a1391a0106c9204fe45bc73a039f056558cb83"
variable (R : Type*) {S : Type*} [CommRing R] [CommRing S] [Algebra R S]
open Ideal Polynomial DoubleQuot UniqueFactorizationMonoid Algebra RingHom
local notation:max R "<" x:max ">" => adjoin R ({x} : Set S)
def conductor (x : S) : Ideal S where
carrier := {a | ∀ b : S, a * b ∈ R<x>}
zero_mem' b := by simpa only [zero_mul] using Subalgebra.zero_mem _
add_mem' ha hb c := by simpa only [add_mul] using Subalgebra.add_mem _ (ha c) (hb c)
smul_mem' c a ha b := by simpa only [smul_eq_mul, mul_left_comm, mul_assoc] using ha (c * b)
#align conductor conductor
variable {R} {x : S}
theorem conductor_eq_of_eq {y : S} (h : (R<x> : Set S) = R<y>) : conductor R x = conductor R y :=
Ideal.ext fun _ => forall_congr' fun _ => Set.ext_iff.mp h _
#align conductor_eq_of_eq conductor_eq_of_eq
theorem conductor_subset_adjoin : (conductor R x : Set S) ⊆ R<x> := fun y hy => by
simpa only [mul_one] using hy 1
#align conductor_subset_adjoin conductor_subset_adjoin
theorem mem_conductor_iff {y : S} : y ∈ conductor R x ↔ ∀ b : S, y * b ∈ R<x> :=
⟨fun h => h, fun h => h⟩
#align mem_conductor_iff mem_conductor_iff
theorem conductor_eq_top_of_adjoin_eq_top (h : R<x> = ⊤) : conductor R x = ⊤ := by
simp only [Ideal.eq_top_iff_one, mem_conductor_iff, h, mem_top, forall_const]
#align conductor_eq_top_of_adjoin_eq_top conductor_eq_top_of_adjoin_eq_top
theorem conductor_eq_top_of_powerBasis (pb : PowerBasis R S) : conductor R pb.gen = ⊤ :=
conductor_eq_top_of_adjoin_eq_top pb.adjoin_gen_eq_top
#align conductor_eq_top_of_power_basis conductor_eq_top_of_powerBasis
open IsLocalization in
lemma mem_coeSubmodule_conductor {L} [CommRing L] [Algebra S L] [Algebra R L]
[IsScalarTower R S L] [NoZeroSMulDivisors S L] {x : S} {y : L} :
y ∈ coeSubmodule L (conductor R x) ↔ ∀ z : S,
y * (algebraMap S L) z ∈ Algebra.adjoin R {algebraMap S L x} := by
cases subsingleton_or_nontrivial L
· rw [Subsingleton.elim (coeSubmodule L _) ⊤, Subsingleton.elim (Algebra.adjoin R _) ⊤]; simp
trans ∀ z, y * (algebraMap S L) z ∈ (Algebra.adjoin R {x}).map (IsScalarTower.toAlgHom R S L)
· simp only [coeSubmodule, Submodule.mem_map, Algebra.linearMap_apply, Subalgebra.mem_map,
IsScalarTower.coe_toAlgHom']
constructor
· rintro ⟨y, hy, rfl⟩ z
exact ⟨_, hy z, map_mul _ _ _⟩
· intro H
obtain ⟨y, _, e⟩ := H 1
rw [_root_.map_one, mul_one] at e
subst e
simp only [← _root_.map_mul, (NoZeroSMulDivisors.algebraMap_injective S L).eq_iff,
exists_eq_right] at H
exact ⟨_, H, rfl⟩
· rw [AlgHom.map_adjoin, Set.image_singleton]; rfl
variable {I : Ideal R}
theorem prod_mem_ideal_map_of_mem_conductor {p : R} {z : S}
(hp : p ∈ Ideal.comap (algebraMap R S) (conductor R x)) (hz' : z ∈ I.map (algebraMap R S)) :
algebraMap R S p * z ∈ algebraMap R<x> S '' ↑(I.map (algebraMap R R<x>)) := by
rw [Ideal.map, Ideal.span, Finsupp.mem_span_image_iff_total] at hz'
obtain ⟨l, H, H'⟩ := hz'
rw [Finsupp.total_apply] at H'
rw [← H', mul_comm, Finsupp.sum_mul]
have lem : ∀ {a : R}, a ∈ I → l a • algebraMap R S a * algebraMap R S p ∈
algebraMap R<x> S '' I.map (algebraMap R R<x>) := by
intro a ha
rw [Algebra.id.smul_eq_mul, mul_assoc, mul_comm, mul_assoc, Set.mem_image]
refine Exists.intro
(algebraMap R R<x> a * ⟨l a * algebraMap R S p,
show l a * algebraMap R S p ∈ R<x> from ?h⟩) ?_
case h =>
rw [mul_comm]
exact mem_conductor_iff.mp (Ideal.mem_comap.mp hp) _
· refine ⟨?_, ?_⟩
· rw [mul_comm]
apply Ideal.mul_mem_left (I.map (algebraMap R R<x>)) _ (Ideal.mem_map_of_mem _ ha)
· simp only [RingHom.map_mul, mul_comm (algebraMap R S p) (l a)]
rfl
refine Finset.sum_induction _ (fun u => u ∈ algebraMap R<x> S '' I.map (algebraMap R R<x>))
(fun a b => ?_) ?_ ?_
· rintro ⟨z, hz, rfl⟩ ⟨y, hy, rfl⟩
rw [← RingHom.map_add]
exact ⟨z + y, Ideal.add_mem _ (SetLike.mem_coe.mp hz) hy, rfl⟩
· exact ⟨0, SetLike.mem_coe.mpr <| Ideal.zero_mem _, RingHom.map_zero _⟩
· intro y hy
exact lem ((Finsupp.mem_supported _ l).mp H hy)
#align prod_mem_ideal_map_of_mem_conductor prod_mem_ideal_map_of_mem_conductor
theorem comap_map_eq_map_adjoin_of_coprime_conductor
(hx : (conductor R x).comap (algebraMap R S) ⊔ I = ⊤)
(h_alg : Function.Injective (algebraMap R<x> S)) :
(I.map (algebraMap R S)).comap (algebraMap R<x> S) = I.map (algebraMap R R<x>) := by
apply le_antisymm
· -- This is adapted from [Neukirch1992]. Let `C = (conductor R x)`. The idea of the proof
-- is that since `I` and `C ∩ R` are coprime, we have
-- `(I * S) ∩ R<x> ⊆ (I + C) * ((I * S) ∩ R<x>) ⊆ I * R<x> + I * C * S ⊆ I * R<x>`.
intro y hy
obtain ⟨z, hz⟩ := y
obtain ⟨p, hp, q, hq, hpq⟩ := Submodule.mem_sup.mp ((Ideal.eq_top_iff_one _).mp hx)
have temp : algebraMap R S p * z + algebraMap R S q * z = z := by
simp only [← add_mul, ← RingHom.map_add (algebraMap R S), hpq, map_one, one_mul]
suffices z ∈ algebraMap R<x> S '' I.map (algebraMap R R<x>) ↔
(⟨z, hz⟩ : R<x>) ∈ I.map (algebraMap R R<x>) by
rw [← this, ← temp]
obtain ⟨a, ha⟩ := (Set.mem_image _ _ _).mp (prod_mem_ideal_map_of_mem_conductor hp
(show z ∈ I.map (algebraMap R S) by rwa [Ideal.mem_comap] at hy))
use a + algebraMap R R<x> q * ⟨z, hz⟩
refine ⟨Ideal.add_mem (I.map (algebraMap R R<x>)) ha.left ?_, by
simp only [ha.right, map_add, AlgHom.map_mul, add_right_inj]; rfl⟩
rw [mul_comm]
exact Ideal.mul_mem_left (I.map (algebraMap R R<x>)) _ (Ideal.mem_map_of_mem _ hq)
refine ⟨fun h => ?_,
fun h => (Set.mem_image _ _ _).mpr (Exists.intro ⟨z, hz⟩ ⟨by simp [h], rfl⟩)⟩
obtain ⟨x₁, hx₁, hx₂⟩ := (Set.mem_image _ _ _).mp h
have : x₁ = ⟨z, hz⟩ := by
apply h_alg
simp [hx₂]
rfl
rwa [← this]
· -- The converse inclusion is trivial
have : algebraMap R S = (algebraMap _ S).comp (algebraMap R R<x>) := by ext; rfl
rw [this, ← Ideal.map_map]
apply Ideal.le_comap_map
#align comap_map_eq_map_adjoin_of_coprime_conductor comap_map_eq_map_adjoin_of_coprime_conductor
noncomputable def quotAdjoinEquivQuotMap (hx : (conductor R x).comap (algebraMap R S) ⊔ I = ⊤)
(h_alg : Function.Injective (algebraMap R<x> S)) :
R<x> ⧸ I.map (algebraMap R R<x>) ≃+* S ⧸ I.map (algebraMap R S) := by
let f : R<x> ⧸ I.map (algebraMap R R<x>) →+* S ⧸ I.map (algebraMap R S) :=
(Ideal.Quotient.lift (I.map (algebraMap R R<x>))
((Ideal.Quotient.mk (I.map (algebraMap R S))).comp (algebraMap R<x> S)) (fun r hr => by
have : algebraMap R S = (algebraMap R<x> S).comp (algebraMap R R<x>) := by ext; rfl
rw [RingHom.comp_apply, Ideal.Quotient.eq_zero_iff_mem, this, ← Ideal.map_map]
exact Ideal.mem_map_of_mem _ hr))
refine RingEquiv.ofBijective f ⟨?_, ?_⟩
· --the kernel of the map is clearly `(I * S) ∩ R<x>`. To get injectivity, we need to show that
--this is contained in `I * R<x>`, which is the content of the previous lemma.
refine RingHom.lift_injective_of_ker_le_ideal _ _ fun u hu => ?_
rwa [RingHom.mem_ker, RingHom.comp_apply, Ideal.Quotient.eq_zero_iff_mem, ← Ideal.mem_comap,
comap_map_eq_map_adjoin_of_coprime_conductor hx h_alg] at hu
· -- Surjectivity follows from the surjectivity of the canonical map `R<x> → S ⧸ (I * S)`,
-- which in turn follows from the fact that `I * S + (conductor R x) = S`.
refine Ideal.Quotient.lift_surjective_of_surjective _ _ fun y => ?_
obtain ⟨z, hz⟩ := Ideal.Quotient.mk_surjective y
have : z ∈ conductor R x ⊔ I.map (algebraMap R S) := by
suffices conductor R x ⊔ I.map (algebraMap R S) = ⊤ by simp only [this, Submodule.mem_top]
rw [Ideal.eq_top_iff_one] at hx ⊢
replace hx := Ideal.mem_map_of_mem (algebraMap R S) hx
rw [Ideal.map_sup, RingHom.map_one] at hx
exact (sup_le_sup
(show ((conductor R x).comap (algebraMap R S)).map (algebraMap R S) ≤ conductor R x
from Ideal.map_comap_le)
(le_refl (I.map (algebraMap R S)))) hx
rw [← Ideal.mem_quotient_iff_mem_sup, hz, Ideal.mem_map_iff_of_surjective] at this
· obtain ⟨u, hu, hu'⟩ := this
use ⟨u, conductor_subset_adjoin hu⟩
simp only [← hu']
rfl
· exact Ideal.Quotient.mk_surjective
#align quot_adjoin_equiv_quot_map quotAdjoinEquivQuotMap
-- Porting note: on-line linter fails with `failed to synthesize` instance
-- but #lint does not report any problem
@[simp, nolint simpNF]
theorem quotAdjoinEquivQuotMap_apply_mk (hx : (conductor R x).comap (algebraMap R S) ⊔ I = ⊤)
(h_alg : Function.Injective (algebraMap R<x> S)) (a : R<x>) :
quotAdjoinEquivQuotMap hx h_alg (Ideal.Quotient.mk (I.map (algebraMap R R<x>)) a) =
Ideal.Quotient.mk (I.map (algebraMap R S)) ↑a := rfl
#align quot_adjoin_equiv_quot_map_apply_mk quotAdjoinEquivQuotMap_apply_mk
namespace KummerDedekind
open scoped Polynomial Classical
variable [IsDomain R] [IsIntegrallyClosed R]
variable [IsDedekindDomain S]
variable [NoZeroSMulDivisors R S]
attribute [local instance] Ideal.Quotient.field
noncomputable def normalizedFactorsMapEquivNormalizedFactorsMinPolyMk (hI : IsMaximal I)
(hI' : I ≠ ⊥) (hx : (conductor R x).comap (algebraMap R S) ⊔ I = ⊤) (hx' : IsIntegral R x) :
{J : Ideal S | J ∈ normalizedFactors (I.map (algebraMap R S))} ≃
{d : (R ⧸ I)[X] |
d ∈ normalizedFactors (Polynomial.map (Ideal.Quotient.mk I) (minpoly R x))} := by
-- Porting note: Lean needs to be reminded about this so it does not time out
have : IsPrincipalIdealRing (R ⧸ I)[X] := inferInstance
let f : S ⧸ map (algebraMap R S) I ≃+*
(R ⧸ I)[X] ⧸ span {Polynomial.map (Ideal.Quotient.mk I) (minpoly R x)} := by
refine (quotAdjoinEquivQuotMap hx ?_).symm.trans
(((Algebra.adjoin.powerBasis'
hx').quotientEquivQuotientMinpolyMap I).toRingEquiv.trans (quotEquivOfEq ?_))
· exact NoZeroSMulDivisors.algebraMap_injective (Algebra.adjoin R {x}) S
· rw [Algebra.adjoin.powerBasis'_minpoly_gen hx']
refine (normalizedFactorsEquivOfQuotEquiv f ?_ ?_).trans ?_
· rwa [Ne, map_eq_bot_iff_of_injective (NoZeroSMulDivisors.algebraMap_injective R S), ← Ne]
· by_contra h
exact (show Polynomial.map (Ideal.Quotient.mk I) (minpoly R x) ≠ 0 from
Polynomial.map_monic_ne_zero (minpoly.monic hx')) (span_singleton_eq_bot.mp h)
· refine (normalizedFactorsEquivSpanNormalizedFactors ?_).symm
exact Polynomial.map_monic_ne_zero (minpoly.monic hx')
#align kummer_dedekind.normalized_factors_map_equiv_normalized_factors_min_poly_mk KummerDedekind.normalizedFactorsMapEquivNormalizedFactorsMinPolyMk
theorem multiplicity_factors_map_eq_multiplicity (hI : IsMaximal I) (hI' : I ≠ ⊥)
(hx : (conductor R x).comap (algebraMap R S) ⊔ I = ⊤) (hx' : IsIntegral R x) {J : Ideal S}
(hJ : J ∈ normalizedFactors (I.map (algebraMap R S))) :
multiplicity J (I.map (algebraMap R S)) =
multiplicity (↑(normalizedFactorsMapEquivNormalizedFactorsMinPolyMk hI hI' hx hx' ⟨J, hJ⟩))
(Polynomial.map (Ideal.Quotient.mk I) (minpoly R x)) := by
rw [normalizedFactorsMapEquivNormalizedFactorsMinPolyMk, Equiv.coe_trans, Function.comp_apply,
multiplicity_normalizedFactorsEquivSpanNormalizedFactors_symm_eq_multiplicity,
normalizedFactorsEquivOfQuotEquiv_multiplicity_eq_multiplicity]
#align kummer_dedekind.multiplicity_factors_map_eq_multiplicity KummerDedekind.multiplicity_factors_map_eq_multiplicity
theorem normalizedFactors_ideal_map_eq_normalizedFactors_min_poly_mk_map (hI : IsMaximal I)
(hI' : I ≠ ⊥) (hx : (conductor R x).comap (algebraMap R S) ⊔ I = ⊤) (hx' : IsIntegral R x) :
normalizedFactors (I.map (algebraMap R S)) =
Multiset.map
(fun f =>
((normalizedFactorsMapEquivNormalizedFactorsMinPolyMk hI hI' hx hx').symm f : Ideal S))
(normalizedFactors (Polynomial.map (Ideal.Quotient.mk I) (minpoly R x))).attach := by
ext J
-- WLOG, assume J is a normalized factor
by_cases hJ : J ∈ normalizedFactors (I.map (algebraMap R S));
swap
· rw [Multiset.count_eq_zero.mpr hJ, eq_comm, Multiset.count_eq_zero, Multiset.mem_map]
simp only [Multiset.mem_attach, true_and_iff, not_exists]
rintro J' rfl
exact
hJ ((normalizedFactorsMapEquivNormalizedFactorsMinPolyMk hI hI' hx hx').symm J').prop
-- Then we just have to compare the multiplicities, which we already proved are equal.
have := multiplicity_factors_map_eq_multiplicity hI hI' hx hx' hJ
rw [multiplicity_eq_count_normalizedFactors, multiplicity_eq_count_normalizedFactors,
UniqueFactorizationMonoid.normalize_normalized_factor _ hJ,
UniqueFactorizationMonoid.normalize_normalized_factor, PartENat.natCast_inj] at this
· refine this.trans ?_
-- Get rid of the `map` by applying the equiv to both sides.
generalize hJ' :
(normalizedFactorsMapEquivNormalizedFactorsMinPolyMk hI hI' hx hx') ⟨J, hJ⟩ = J'
have : ((normalizedFactorsMapEquivNormalizedFactorsMinPolyMk hI hI' hx hx').symm J' : Ideal S) =
J := by
rw [← hJ', Equiv.symm_apply_apply _ _, Subtype.coe_mk]
subst this
-- Get rid of the `attach` by applying the subtype `coe` to both sides.
rw [Multiset.count_map_eq_count' fun f =>
((normalizedFactorsMapEquivNormalizedFactorsMinPolyMk hI hI' hx hx').symm f :
Ideal S),
Multiset.count_attach]
· exact Subtype.coe_injective.comp (Equiv.injective _)
· exact (normalizedFactorsMapEquivNormalizedFactorsMinPolyMk hI hI' hx hx' _).prop
· exact irreducible_of_normalized_factor _
(normalizedFactorsMapEquivNormalizedFactorsMinPolyMk hI hI' hx hx' _).prop
· exact Polynomial.map_monic_ne_zero (minpoly.monic hx')
· exact irreducible_of_normalized_factor _ hJ
· rwa [← bot_eq_zero, Ne,
map_eq_bot_iff_of_injective (NoZeroSMulDivisors.algebraMap_injective R S)]
#align kummer_dedekind.normalized_factors_ideal_map_eq_normalized_factors_min_poly_mk_map KummerDedekind.normalizedFactors_ideal_map_eq_normalizedFactors_min_poly_mk_map
| Mathlib/NumberTheory/KummerDedekind.lean | 330 | 356 | theorem Ideal.irreducible_map_of_irreducible_minpoly (hI : IsMaximal I) (hI' : I ≠ ⊥)
(hx : (conductor R x).comap (algebraMap R S) ⊔ I = ⊤) (hx' : IsIntegral R x)
(hf : Irreducible (Polynomial.map (Ideal.Quotient.mk I) (minpoly R x))) :
Irreducible (I.map (algebraMap R S)) := by |
have mem_norm_factors : normalize (Polynomial.map (Ideal.Quotient.mk I) (minpoly R x)) ∈
normalizedFactors (Polynomial.map (Ideal.Quotient.mk I) (minpoly R x)) := by
simp [normalizedFactors_irreducible hf]
suffices ∃ y, normalizedFactors (I.map (algebraMap R S)) = {y} by
obtain ⟨y, hy⟩ := this
have h := normalizedFactors_prod (show I.map (algebraMap R S) ≠ 0 by
rwa [← bot_eq_zero, Ne,
map_eq_bot_iff_of_injective (NoZeroSMulDivisors.algebraMap_injective R S)])
rw [associated_iff_eq, hy, Multiset.prod_singleton] at h
rw [← h]
exact
irreducible_of_normalized_factor y
(show y ∈ normalizedFactors (I.map (algebraMap R S)) by simp [hy])
rw [normalizedFactors_ideal_map_eq_normalizedFactors_min_poly_mk_map hI hI' hx hx']
use ((normalizedFactorsMapEquivNormalizedFactorsMinPolyMk hI hI' hx hx').symm
⟨normalize (Polynomial.map (Ideal.Quotient.mk I) (minpoly R x)), mem_norm_factors⟩ :
Ideal S)
rw [Multiset.map_eq_singleton]
use ⟨normalize (Polynomial.map (Ideal.Quotient.mk I) (minpoly R x)), mem_norm_factors⟩
refine ⟨?_, rfl⟩
apply Multiset.map_injective Subtype.coe_injective
rw [Multiset.attach_map_val, Multiset.map_singleton, Subtype.coe_mk]
exact normalizedFactors_irreducible hf
|
import Mathlib.Data.Matrix.Notation
import Mathlib.Data.Matrix.Basic
import Mathlib.Data.Fin.Tuple.Reflection
#align_import data.matrix.reflection from "leanprover-community/mathlib"@"820b22968a2bc4a47ce5cf1d2f36a9ebe52510aa"
open Matrix
namespace Matrix
variable {l m n : ℕ} {α β : Type*}
def Forall : ∀ {m n} (_ : Matrix (Fin m) (Fin n) α → Prop), Prop
| 0, _, P => P (of ![])
| _ + 1, _, P => FinVec.Forall fun r => Forall fun A => P (of (Matrix.vecCons r A))
#align matrix.forall Matrix.Forall
theorem forall_iff : ∀ {m n} (P : Matrix (Fin m) (Fin n) α → Prop), Forall P ↔ ∀ x, P x
| 0, n, P => Iff.symm Fin.forall_fin_zero_pi
| m + 1, n, P => by
simp only [Forall, FinVec.forall_iff, forall_iff]
exact Iff.symm Fin.forall_fin_succ_pi
#align matrix.forall_iff Matrix.forall_iff
example (P : Matrix (Fin 2) (Fin 3) α → Prop) :
(∀ x, P x) ↔ ∀ a b c d e f, P !![a, b, c; d, e, f] :=
(forall_iff _).symm
def Exists : ∀ {m n} (_ : Matrix (Fin m) (Fin n) α → Prop), Prop
| 0, _, P => P (of ![])
| _ + 1, _, P => FinVec.Exists fun r => Exists fun A => P (of (Matrix.vecCons r A))
#align matrix.exists Matrix.Exists
theorem exists_iff : ∀ {m n} (P : Matrix (Fin m) (Fin n) α → Prop), Exists P ↔ ∃ x, P x
| 0, n, P => Iff.symm Fin.exists_fin_zero_pi
| m + 1, n, P => by
simp only [Exists, FinVec.exists_iff, exists_iff]
exact Iff.symm Fin.exists_fin_succ_pi
#align matrix.exists_iff Matrix.exists_iff
example (P : Matrix (Fin 2) (Fin 3) α → Prop) :
(∃ x, P x) ↔ ∃ a b c d e f, P !![a, b, c; d, e, f] :=
(exists_iff _).symm
def transposeᵣ : ∀ {m n}, Matrix (Fin m) (Fin n) α → Matrix (Fin n) (Fin m) α
| _, 0, _ => of ![]
| _, _ + 1, A =>
of <| vecCons (FinVec.map (fun v : Fin _ → α => v 0) A) (transposeᵣ (A.submatrix id Fin.succ))
#align matrix.transposeᵣ Matrix.transposeᵣ
@[simp]
theorem transposeᵣ_eq : ∀ {m n} (A : Matrix (Fin m) (Fin n) α), transposeᵣ A = transpose A
| _, 0, A => Subsingleton.elim _ _
| m, n + 1, A =>
Matrix.ext fun i j => by
simp_rw [transposeᵣ, transposeᵣ_eq]
refine i.cases ?_ fun i => ?_
· dsimp
rw [FinVec.map_eq, Function.comp_apply]
· simp only [of_apply, Matrix.cons_val_succ]
rfl
#align matrix.transposeᵣ_eq Matrix.transposeᵣ_eq
example (a b c d : α) : transpose !![a, b; c, d] = !![a, c; b, d] :=
(transposeᵣ_eq _).symm
def dotProductᵣ [Mul α] [Add α] [Zero α] {m} (a b : Fin m → α) : α :=
FinVec.sum <| FinVec.seq (FinVec.map (· * ·) a) b
#align matrix.dot_productᵣ Matrix.dotProductᵣ
@[simp]
theorem dotProductᵣ_eq [Mul α] [AddCommMonoid α] {m} (a b : Fin m → α) :
dotProductᵣ a b = dotProduct a b := by
simp_rw [dotProductᵣ, dotProduct, FinVec.sum_eq, FinVec.seq_eq, FinVec.map_eq,
Function.comp_apply]
#align matrix.dot_productᵣ_eq Matrix.dotProductᵣ_eq
example (a b c d : α) [Mul α] [AddCommMonoid α] : dotProduct ![a, b] ![c, d] = a * c + b * d :=
(dotProductᵣ_eq _ _).symm
def mulᵣ [Mul α] [Add α] [Zero α] (A : Matrix (Fin l) (Fin m) α) (B : Matrix (Fin m) (Fin n) α) :
Matrix (Fin l) (Fin n) α :=
of <| FinVec.map (fun v₁ => FinVec.map (fun v₂ => dotProductᵣ v₁ v₂) Bᵀ) A
#align matrix.mulᵣ Matrix.mulᵣ
@[simp]
| Mathlib/Data/Matrix/Reflection.lean | 159 | 162 | theorem mulᵣ_eq [Mul α] [AddCommMonoid α] (A : Matrix (Fin l) (Fin m) α)
(B : Matrix (Fin m) (Fin n) α) : mulᵣ A B = A * B := by |
simp [mulᵣ, Function.comp, Matrix.transpose]
rfl
|
import Mathlib.Analysis.Convex.StrictConvexBetween
import Mathlib.Geometry.Euclidean.Basic
#align_import geometry.euclidean.sphere.basic from "leanprover-community/mathlib"@"46b633fd842bef9469441c0209906f6dddd2b4f5"
noncomputable section
open RealInnerProductSpace
namespace EuclideanGeometry
variable {V : Type*} (P : Type*)
open FiniteDimensional
@[ext]
structure Sphere [MetricSpace P] where
center : P
radius : ℝ
#align euclidean_geometry.sphere EuclideanGeometry.Sphere
variable {P}
section MetricSpace
variable [MetricSpace P]
instance [Nonempty P] : Nonempty (Sphere P) :=
⟨⟨Classical.arbitrary P, 0⟩⟩
instance : Coe (Sphere P) (Set P) :=
⟨fun s => Metric.sphere s.center s.radius⟩
instance : Membership P (Sphere P) :=
⟨fun p s => p ∈ (s : Set P)⟩
theorem Sphere.mk_center (c : P) (r : ℝ) : (⟨c, r⟩ : Sphere P).center = c :=
rfl
#align euclidean_geometry.sphere.mk_center EuclideanGeometry.Sphere.mk_center
theorem Sphere.mk_radius (c : P) (r : ℝ) : (⟨c, r⟩ : Sphere P).radius = r :=
rfl
#align euclidean_geometry.sphere.mk_radius EuclideanGeometry.Sphere.mk_radius
@[simp]
theorem Sphere.mk_center_radius (s : Sphere P) : (⟨s.center, s.radius⟩ : Sphere P) = s := by
ext <;> rfl
#align euclidean_geometry.sphere.mk_center_radius EuclideanGeometry.Sphere.mk_center_radius
#noalign euclidean_geometry.sphere.coe_def
@[simp]
theorem Sphere.coe_mk (c : P) (r : ℝ) : ↑(⟨c, r⟩ : Sphere P) = Metric.sphere c r :=
rfl
#align euclidean_geometry.sphere.coe_mk EuclideanGeometry.Sphere.coe_mk
-- @[simp] -- Porting note: simp-normal form is `Sphere.mem_coe'`
theorem Sphere.mem_coe {p : P} {s : Sphere P} : p ∈ (s : Set P) ↔ p ∈ s :=
Iff.rfl
#align euclidean_geometry.sphere.mem_coe EuclideanGeometry.Sphere.mem_coe
@[simp]
theorem Sphere.mem_coe' {p : P} {s : Sphere P} : dist p s.center = s.radius ↔ p ∈ s :=
Iff.rfl
theorem mem_sphere {p : P} {s : Sphere P} : p ∈ s ↔ dist p s.center = s.radius :=
Iff.rfl
#align euclidean_geometry.mem_sphere EuclideanGeometry.mem_sphere
theorem mem_sphere' {p : P} {s : Sphere P} : p ∈ s ↔ dist s.center p = s.radius :=
Metric.mem_sphere'
#align euclidean_geometry.mem_sphere' EuclideanGeometry.mem_sphere'
theorem subset_sphere {ps : Set P} {s : Sphere P} : ps ⊆ s ↔ ∀ p ∈ ps, p ∈ s :=
Iff.rfl
#align euclidean_geometry.subset_sphere EuclideanGeometry.subset_sphere
theorem dist_of_mem_subset_sphere {p : P} {ps : Set P} {s : Sphere P} (hp : p ∈ ps)
(hps : ps ⊆ (s : Set P)) : dist p s.center = s.radius :=
mem_sphere.1 (Sphere.mem_coe.1 (Set.mem_of_mem_of_subset hp hps))
#align euclidean_geometry.dist_of_mem_subset_sphere EuclideanGeometry.dist_of_mem_subset_sphere
theorem dist_of_mem_subset_mk_sphere {p c : P} {ps : Set P} {r : ℝ} (hp : p ∈ ps)
(hps : ps ⊆ ↑(⟨c, r⟩ : Sphere P)) : dist p c = r :=
dist_of_mem_subset_sphere hp hps
#align euclidean_geometry.dist_of_mem_subset_mk_sphere EuclideanGeometry.dist_of_mem_subset_mk_sphere
theorem Sphere.ne_iff {s₁ s₂ : Sphere P} :
s₁ ≠ s₂ ↔ s₁.center ≠ s₂.center ∨ s₁.radius ≠ s₂.radius := by
rw [← not_and_or, ← Sphere.ext_iff]
#align euclidean_geometry.sphere.ne_iff EuclideanGeometry.Sphere.ne_iff
| Mathlib/Geometry/Euclidean/Sphere/Basic.lean | 124 | 128 | theorem Sphere.center_eq_iff_eq_of_mem {s₁ s₂ : Sphere P} {p : P} (hs₁ : p ∈ s₁) (hs₂ : p ∈ s₂) :
s₁.center = s₂.center ↔ s₁ = s₂ := by |
refine ⟨fun h => Sphere.ext _ _ h ?_, fun h => h ▸ rfl⟩
rw [mem_sphere] at hs₁ hs₂
rw [← hs₁, ← hs₂, h]
|
import Mathlib.Data.Complex.Module
import Mathlib.Data.Complex.Order
import Mathlib.Data.Complex.Exponential
import Mathlib.Analysis.RCLike.Basic
import Mathlib.Topology.Algebra.InfiniteSum.Module
import Mathlib.Topology.Instances.RealVectorSpace
#align_import analysis.complex.basic from "leanprover-community/mathlib"@"3f655f5297b030a87d641ad4e825af8d9679eb0b"
assert_not_exists Absorbs
noncomputable section
namespace Complex
variable {z : ℂ}
open ComplexConjugate Topology Filter
instance : Norm ℂ :=
⟨abs⟩
@[simp]
theorem norm_eq_abs (z : ℂ) : ‖z‖ = abs z :=
rfl
#align complex.norm_eq_abs Complex.norm_eq_abs
lemma norm_I : ‖I‖ = 1 := abs_I
theorem norm_exp_ofReal_mul_I (t : ℝ) : ‖exp (t * I)‖ = 1 := by
simp only [norm_eq_abs, abs_exp_ofReal_mul_I]
set_option linter.uppercaseLean3 false in
#align complex.norm_exp_of_real_mul_I Complex.norm_exp_ofReal_mul_I
instance instNormedAddCommGroup : NormedAddCommGroup ℂ :=
AddGroupNorm.toNormedAddCommGroup
{ abs with
map_zero' := map_zero abs
neg' := abs.map_neg
eq_zero_of_map_eq_zero' := fun _ => abs.eq_zero.1 }
instance : NormedField ℂ where
dist_eq _ _ := rfl
norm_mul' := map_mul abs
instance : DenselyNormedField ℂ where
lt_norm_lt r₁ r₂ h₀ hr :=
let ⟨x, h⟩ := exists_between hr
⟨x, by rwa [norm_eq_abs, abs_ofReal, abs_of_pos (h₀.trans_lt h.1)]⟩
instance {R : Type*} [NormedField R] [NormedAlgebra R ℝ] : NormedAlgebra R ℂ where
norm_smul_le r x := by
rw [← algebraMap_smul ℝ r x, real_smul, norm_mul, norm_eq_abs, abs_ofReal, ← Real.norm_eq_abs,
norm_algebraMap']
variable {E : Type*} [SeminormedAddCommGroup E] [NormedSpace ℂ E]
-- see Note [lower instance priority]
instance (priority := 900) _root_.NormedSpace.complexToReal : NormedSpace ℝ E :=
NormedSpace.restrictScalars ℝ ℂ E
#align normed_space.complex_to_real NormedSpace.complexToReal
-- see Note [lower instance priority]
instance (priority := 900) _root_.NormedAlgebra.complexToReal {A : Type*} [SeminormedRing A]
[NormedAlgebra ℂ A] : NormedAlgebra ℝ A :=
NormedAlgebra.restrictScalars ℝ ℂ A
theorem dist_eq (z w : ℂ) : dist z w = abs (z - w) :=
rfl
#align complex.dist_eq Complex.dist_eq
theorem dist_eq_re_im (z w : ℂ) : dist z w = √((z.re - w.re) ^ 2 + (z.im - w.im) ^ 2) := by
rw [sq, sq]
rfl
#align complex.dist_eq_re_im Complex.dist_eq_re_im
@[simp]
theorem dist_mk (x₁ y₁ x₂ y₂ : ℝ) :
dist (mk x₁ y₁) (mk x₂ y₂) = √((x₁ - x₂) ^ 2 + (y₁ - y₂) ^ 2) :=
dist_eq_re_im _ _
#align complex.dist_mk Complex.dist_mk
theorem dist_of_re_eq {z w : ℂ} (h : z.re = w.re) : dist z w = dist z.im w.im := by
rw [dist_eq_re_im, h, sub_self, zero_pow two_ne_zero, zero_add, Real.sqrt_sq_eq_abs, Real.dist_eq]
#align complex.dist_of_re_eq Complex.dist_of_re_eq
theorem nndist_of_re_eq {z w : ℂ} (h : z.re = w.re) : nndist z w = nndist z.im w.im :=
NNReal.eq <| dist_of_re_eq h
#align complex.nndist_of_re_eq Complex.nndist_of_re_eq
theorem edist_of_re_eq {z w : ℂ} (h : z.re = w.re) : edist z w = edist z.im w.im := by
rw [edist_nndist, edist_nndist, nndist_of_re_eq h]
#align complex.edist_of_re_eq Complex.edist_of_re_eq
theorem dist_of_im_eq {z w : ℂ} (h : z.im = w.im) : dist z w = dist z.re w.re := by
rw [dist_eq_re_im, h, sub_self, zero_pow two_ne_zero, add_zero, Real.sqrt_sq_eq_abs, Real.dist_eq]
#align complex.dist_of_im_eq Complex.dist_of_im_eq
theorem nndist_of_im_eq {z w : ℂ} (h : z.im = w.im) : nndist z w = nndist z.re w.re :=
NNReal.eq <| dist_of_im_eq h
#align complex.nndist_of_im_eq Complex.nndist_of_im_eq
theorem edist_of_im_eq {z w : ℂ} (h : z.im = w.im) : edist z w = edist z.re w.re := by
rw [edist_nndist, edist_nndist, nndist_of_im_eq h]
#align complex.edist_of_im_eq Complex.edist_of_im_eq
theorem dist_conj_self (z : ℂ) : dist (conj z) z = 2 * |z.im| := by
rw [dist_of_re_eq (conj_re z), conj_im, dist_comm, Real.dist_eq, sub_neg_eq_add, ← two_mul,
_root_.abs_mul, abs_of_pos (zero_lt_two' ℝ)]
#align complex.dist_conj_self Complex.dist_conj_self
theorem nndist_conj_self (z : ℂ) : nndist (conj z) z = 2 * Real.nnabs z.im :=
NNReal.eq <| by rw [← dist_nndist, NNReal.coe_mul, NNReal.coe_two, Real.coe_nnabs, dist_conj_self]
#align complex.nndist_conj_self Complex.nndist_conj_self
theorem dist_self_conj (z : ℂ) : dist z (conj z) = 2 * |z.im| := by rw [dist_comm, dist_conj_self]
#align complex.dist_self_conj Complex.dist_self_conj
theorem nndist_self_conj (z : ℂ) : nndist z (conj z) = 2 * Real.nnabs z.im := by
rw [nndist_comm, nndist_conj_self]
#align complex.nndist_self_conj Complex.nndist_self_conj
@[simp 1100]
theorem comap_abs_nhds_zero : comap abs (𝓝 0) = 𝓝 0 :=
comap_norm_nhds_zero
#align complex.comap_abs_nhds_zero Complex.comap_abs_nhds_zero
theorem norm_real (r : ℝ) : ‖(r : ℂ)‖ = ‖r‖ :=
abs_ofReal _
#align complex.norm_real Complex.norm_real
@[simp 1100]
theorem norm_rat (r : ℚ) : ‖(r : ℂ)‖ = |(r : ℝ)| := by
rw [← ofReal_ratCast]
exact norm_real _
#align complex.norm_rat Complex.norm_rat
@[simp 1100]
theorem norm_nat (n : ℕ) : ‖(n : ℂ)‖ = n :=
abs_natCast _
#align complex.norm_nat Complex.norm_nat
@[simp 1100]
lemma norm_int {n : ℤ} : ‖(n : ℂ)‖ = |(n : ℝ)| := abs_intCast n
#align complex.norm_int Complex.norm_int
theorem norm_int_of_nonneg {n : ℤ} (hn : 0 ≤ n) : ‖(n : ℂ)‖ = n := by
rw [norm_int, ← Int.cast_abs, _root_.abs_of_nonneg hn]
#align complex.norm_int_of_nonneg Complex.norm_int_of_nonneg
lemma normSq_eq_norm_sq (z : ℂ) : normSq z = ‖z‖ ^ 2 := by
rw [normSq_eq_abs, norm_eq_abs]
@[continuity]
theorem continuous_abs : Continuous abs :=
continuous_norm
#align complex.continuous_abs Complex.continuous_abs
@[continuity]
| Mathlib/Analysis/Complex/Basic.lean | 190 | 191 | theorem continuous_normSq : Continuous normSq := by |
simpa [← normSq_eq_abs] using continuous_abs.pow 2
|
import Mathlib.Algebra.GeomSum
import Mathlib.Order.Filter.Archimedean
import Mathlib.Order.Iterate
import Mathlib.Topology.Algebra.Algebra
import Mathlib.Topology.Algebra.InfiniteSum.Real
#align_import analysis.specific_limits.basic from "leanprover-community/mathlib"@"57ac39bd365c2f80589a700f9fbb664d3a1a30c2"
noncomputable section
open scoped Classical
open Set Function Filter Finset Metric
open scoped Classical
open Topology Nat uniformity NNReal ENNReal
variable {α : Type*} {β : Type*} {ι : Type*}
theorem tendsto_inverse_atTop_nhds_zero_nat : Tendsto (fun n : ℕ ↦ (n : ℝ)⁻¹) atTop (𝓝 0) :=
tendsto_inv_atTop_zero.comp tendsto_natCast_atTop_atTop
#align tendsto_inverse_at_top_nhds_0_nat tendsto_inverse_atTop_nhds_zero_nat
@[deprecated (since := "2024-01-31")]
alias tendsto_inverse_atTop_nhds_0_nat := tendsto_inverse_atTop_nhds_zero_nat
theorem tendsto_const_div_atTop_nhds_zero_nat (C : ℝ) :
Tendsto (fun n : ℕ ↦ C / n) atTop (𝓝 0) := by
simpa only [mul_zero] using tendsto_const_nhds.mul tendsto_inverse_atTop_nhds_zero_nat
#align tendsto_const_div_at_top_nhds_0_nat tendsto_const_div_atTop_nhds_zero_nat
@[deprecated (since := "2024-01-31")]
alias tendsto_const_div_atTop_nhds_0_nat := tendsto_const_div_atTop_nhds_zero_nat
theorem tendsto_one_div_atTop_nhds_zero_nat : Tendsto (fun n : ℕ ↦ 1/(n : ℝ)) atTop (𝓝 0) :=
tendsto_const_div_atTop_nhds_zero_nat 1
@[deprecated (since := "2024-01-31")]
alias tendsto_one_div_atTop_nhds_0_nat := tendsto_one_div_atTop_nhds_zero_nat
theorem NNReal.tendsto_inverse_atTop_nhds_zero_nat :
Tendsto (fun n : ℕ ↦ (n : ℝ≥0)⁻¹) atTop (𝓝 0) := by
rw [← NNReal.tendsto_coe]
exact _root_.tendsto_inverse_atTop_nhds_zero_nat
#align nnreal.tendsto_inverse_at_top_nhds_0_nat NNReal.tendsto_inverse_atTop_nhds_zero_nat
@[deprecated (since := "2024-01-31")]
alias NNReal.tendsto_inverse_atTop_nhds_0_nat := NNReal.tendsto_inverse_atTop_nhds_zero_nat
| Mathlib/Analysis/SpecificLimits/Basic.lean | 59 | 61 | theorem NNReal.tendsto_const_div_atTop_nhds_zero_nat (C : ℝ≥0) :
Tendsto (fun n : ℕ ↦ C / n) atTop (𝓝 0) := by |
simpa using tendsto_const_nhds.mul NNReal.tendsto_inverse_atTop_nhds_zero_nat
|
import Mathlib.Combinatorics.SimpleGraph.Clique
import Mathlib.Data.ENat.Lattice
import Mathlib.Data.Nat.Lattice
import Mathlib.Data.Setoid.Partition
import Mathlib.Order.Antichain
#align_import combinatorics.simple_graph.coloring from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a"
open Fintype Function
universe u v
namespace SimpleGraph
variable {V : Type u} (G : SimpleGraph V) {n : ℕ}
abbrev Coloring (α : Type v) := G →g (⊤ : SimpleGraph α)
#align simple_graph.coloring SimpleGraph.Coloring
variable {G} {α β : Type*} (C : G.Coloring α)
theorem Coloring.valid {v w : V} (h : G.Adj v w) : C v ≠ C w :=
C.map_rel h
#align simple_graph.coloring.valid SimpleGraph.Coloring.valid
@[match_pattern]
def Coloring.mk (color : V → α) (valid : ∀ {v w : V}, G.Adj v w → color v ≠ color w) :
G.Coloring α :=
⟨color, @valid⟩
#align simple_graph.coloring.mk SimpleGraph.Coloring.mk
def Coloring.colorClass (c : α) : Set V := { v : V | C v = c }
#align simple_graph.coloring.color_class SimpleGraph.Coloring.colorClass
def Coloring.colorClasses : Set (Set V) := (Setoid.ker C).classes
#align simple_graph.coloring.color_classes SimpleGraph.Coloring.colorClasses
theorem Coloring.mem_colorClass (v : V) : v ∈ C.colorClass (C v) := rfl
#align simple_graph.coloring.mem_color_class SimpleGraph.Coloring.mem_colorClass
theorem Coloring.colorClasses_isPartition : Setoid.IsPartition C.colorClasses :=
Setoid.isPartition_classes (Setoid.ker C)
#align simple_graph.coloring.color_classes_is_partition SimpleGraph.Coloring.colorClasses_isPartition
theorem Coloring.mem_colorClasses {v : V} : C.colorClass (C v) ∈ C.colorClasses :=
⟨v, rfl⟩
#align simple_graph.coloring.mem_color_classes SimpleGraph.Coloring.mem_colorClasses
theorem Coloring.colorClasses_finite [Finite α] : C.colorClasses.Finite :=
Setoid.finite_classes_ker _
#align simple_graph.coloring.color_classes_finite SimpleGraph.Coloring.colorClasses_finite
theorem Coloring.card_colorClasses_le [Fintype α] [Fintype C.colorClasses] :
Fintype.card C.colorClasses ≤ Fintype.card α := by
simp [colorClasses]
-- Porting note: brute force instance declaration `[Fintype (Setoid.classes (Setoid.ker C))]`
haveI : Fintype (Setoid.classes (Setoid.ker C)) := by assumption
convert Setoid.card_classes_ker_le C
#align simple_graph.coloring.card_color_classes_le SimpleGraph.Coloring.card_colorClasses_le
theorem Coloring.not_adj_of_mem_colorClass {c : α} {v w : V} (hv : v ∈ C.colorClass c)
(hw : w ∈ C.colorClass c) : ¬G.Adj v w := fun h => C.valid h (Eq.trans hv (Eq.symm hw))
#align simple_graph.coloring.not_adj_of_mem_color_class SimpleGraph.Coloring.not_adj_of_mem_colorClass
theorem Coloring.color_classes_independent (c : α) : IsAntichain G.Adj (C.colorClass c) :=
fun _ hv _ hw _ => C.not_adj_of_mem_colorClass hv hw
#align simple_graph.coloring.color_classes_independent SimpleGraph.Coloring.color_classes_independent
-- TODO make this computable
noncomputable instance [Fintype V] [Fintype α] : Fintype (Coloring G α) := by
classical
change Fintype (RelHom G.Adj (⊤ : SimpleGraph α).Adj)
apply Fintype.ofInjective _ RelHom.coe_fn_injective
variable (G)
def Colorable (n : ℕ) : Prop := Nonempty (G.Coloring (Fin n))
#align simple_graph.colorable SimpleGraph.Colorable
def coloringOfIsEmpty [IsEmpty V] : G.Coloring α :=
Coloring.mk isEmptyElim fun {v} => isEmptyElim v
#align simple_graph.coloring_of_is_empty SimpleGraph.coloringOfIsEmpty
theorem colorable_of_isEmpty [IsEmpty V] (n : ℕ) : G.Colorable n :=
⟨G.coloringOfIsEmpty⟩
#align simple_graph.colorable_of_is_empty SimpleGraph.colorable_of_isEmpty
theorem isEmpty_of_colorable_zero (h : G.Colorable 0) : IsEmpty V := by
constructor
intro v
obtain ⟨i, hi⟩ := h.some v
exact Nat.not_lt_zero _ hi
#align simple_graph.is_empty_of_colorable_zero SimpleGraph.isEmpty_of_colorable_zero
def selfColoring : G.Coloring V := Coloring.mk id fun {_ _} => G.ne_of_adj
#align simple_graph.self_coloring SimpleGraph.selfColoring
noncomputable def chromaticNumber : ℕ∞ := ⨅ n ∈ setOf G.Colorable, (n : ℕ∞)
#align simple_graph.chromatic_number SimpleGraph.chromaticNumber
lemma chromaticNumber_eq_biInf {G : SimpleGraph V} :
G.chromaticNumber = ⨅ n ∈ setOf G.Colorable, (n : ℕ∞) := rfl
lemma chromaticNumber_eq_iInf {G : SimpleGraph V} :
G.chromaticNumber = ⨅ n : {m | G.Colorable m}, (n : ℕ∞) := by
rw [chromaticNumber, iInf_subtype]
lemma Colorable.chromaticNumber_eq_sInf {G : SimpleGraph V} {n} (h : G.Colorable n) :
G.chromaticNumber = sInf {n' : ℕ | G.Colorable n'} := by
rw [ENat.coe_sInf, chromaticNumber]
exact ⟨_, h⟩
def recolorOfEmbedding {α β : Type*} (f : α ↪ β) : G.Coloring α ↪ G.Coloring β where
toFun C := (Embedding.completeGraph f).toHom.comp C
inj' := by -- this was strangely painful; seems like missing lemmas about embeddings
intro C C' h
dsimp only at h
ext v
apply (Embedding.completeGraph f).inj'
change ((Embedding.completeGraph f).toHom.comp C) v = _
rw [h]
rfl
#align simple_graph.recolor_of_embedding SimpleGraph.recolorOfEmbedding
@[simp] lemma coe_recolorOfEmbedding (f : α ↪ β) :
⇑(G.recolorOfEmbedding f) = (Embedding.completeGraph f).toHom.comp := rfl
def recolorOfEquiv {α β : Type*} (f : α ≃ β) : G.Coloring α ≃ G.Coloring β where
toFun := G.recolorOfEmbedding f.toEmbedding
invFun := G.recolorOfEmbedding f.symm.toEmbedding
left_inv C := by
ext v
apply Equiv.symm_apply_apply
right_inv C := by
ext v
apply Equiv.apply_symm_apply
#align simple_graph.recolor_of_equiv SimpleGraph.recolorOfEquiv
@[simp] lemma coe_recolorOfEquiv (f : α ≃ β) :
⇑(G.recolorOfEquiv f) = (Embedding.completeGraph f).toHom.comp := rfl
noncomputable def recolorOfCardLE {α β : Type*} [Fintype α] [Fintype β]
(hn : Fintype.card α ≤ Fintype.card β) : G.Coloring α ↪ G.Coloring β :=
G.recolorOfEmbedding <| (Function.Embedding.nonempty_of_card_le hn).some
#align simple_graph.recolor_of_card_le SimpleGraph.recolorOfCardLE
@[simp] lemma coe_recolorOfCardLE [Fintype α] [Fintype β] (hαβ : card α ≤ card β) :
⇑(G.recolorOfCardLE hαβ) =
(Embedding.completeGraph (Embedding.nonempty_of_card_le hαβ).some).toHom.comp := rfl
variable {G}
theorem Colorable.mono {n m : ℕ} (h : n ≤ m) (hc : G.Colorable n) : G.Colorable m :=
⟨G.recolorOfCardLE (by simp [h]) hc.some⟩
#align simple_graph.colorable.mono SimpleGraph.Colorable.mono
theorem Coloring.colorable [Fintype α] (C : G.Coloring α) : G.Colorable (Fintype.card α) :=
⟨G.recolorOfCardLE (by simp) C⟩
#align simple_graph.coloring.to_colorable SimpleGraph.Coloring.colorable
theorem colorable_of_fintype (G : SimpleGraph V) [Fintype V] : G.Colorable (Fintype.card V) :=
G.selfColoring.colorable
#align simple_graph.colorable_of_fintype SimpleGraph.colorable_of_fintype
noncomputable def Colorable.toColoring [Fintype α] {n : ℕ} (hc : G.Colorable n)
(hn : n ≤ Fintype.card α) : G.Coloring α := by
rw [← Fintype.card_fin n] at hn
exact G.recolorOfCardLE hn hc.some
#align simple_graph.colorable.to_coloring SimpleGraph.Colorable.toColoring
theorem Colorable.of_embedding {V' : Type*} {G' : SimpleGraph V'} (f : G ↪g G') {n : ℕ}
(h : G'.Colorable n) : G.Colorable n :=
⟨(h.toColoring (by simp)).comp f⟩
#align simple_graph.colorable.of_embedding SimpleGraph.Colorable.of_embedding
theorem colorable_iff_exists_bdd_nat_coloring (n : ℕ) :
G.Colorable n ↔ ∃ C : G.Coloring ℕ, ∀ v, C v < n := by
constructor
· rintro hc
have C : G.Coloring (Fin n) := hc.toColoring (by simp)
let f := Embedding.completeGraph (@Fin.valEmbedding n)
use f.toHom.comp C
intro v
cases' C with color valid
exact Fin.is_lt (color v)
· rintro ⟨C, Cf⟩
refine ⟨Coloring.mk ?_ ?_⟩
· exact fun v => ⟨C v, Cf v⟩
· rintro v w hvw
simp only [Fin.mk_eq_mk, Ne]
exact C.valid hvw
#align simple_graph.colorable_iff_exists_bdd_nat_coloring SimpleGraph.colorable_iff_exists_bdd_nat_coloring
theorem colorable_set_nonempty_of_colorable {n : ℕ} (hc : G.Colorable n) :
{ n : ℕ | G.Colorable n }.Nonempty :=
⟨n, hc⟩
#align simple_graph.colorable_set_nonempty_of_colorable SimpleGraph.colorable_set_nonempty_of_colorable
theorem chromaticNumber_bddBelow : BddBelow { n : ℕ | G.Colorable n } :=
⟨0, fun _ _ => zero_le _⟩
#align simple_graph.chromatic_number_bdd_below SimpleGraph.chromaticNumber_bddBelow
theorem Colorable.chromaticNumber_le {n : ℕ} (hc : G.Colorable n) : G.chromaticNumber ≤ n := by
rw [hc.chromaticNumber_eq_sInf]
norm_cast
apply csInf_le chromaticNumber_bddBelow
exact hc
#align simple_graph.chromatic_number_le_of_colorable SimpleGraph.Colorable.chromaticNumber_le
theorem chromaticNumber_ne_top_iff_exists : G.chromaticNumber ≠ ⊤ ↔ ∃ n, G.Colorable n := by
rw [chromaticNumber]
convert_to ⨅ n : {m | G.Colorable m}, (n : ℕ∞) ≠ ⊤ ↔ _
· rw [iInf_subtype]
rw [← lt_top_iff_ne_top, ENat.iInf_coe_lt_top]
simp
theorem chromaticNumber_le_iff_colorable {n : ℕ} : G.chromaticNumber ≤ n ↔ G.Colorable n := by
refine ⟨fun h ↦ ?_, Colorable.chromaticNumber_le⟩
have : G.chromaticNumber ≠ ⊤ := (trans h (WithTop.coe_lt_top n)).ne
rw [chromaticNumber_ne_top_iff_exists] at this
obtain ⟨m, hm⟩ := this
rw [hm.chromaticNumber_eq_sInf, Nat.cast_le] at h
have := Nat.sInf_mem (⟨m, hm⟩ : {n' | G.Colorable n'}.Nonempty)
rw [Set.mem_setOf_eq] at this
exact this.mono h
@[deprecated Colorable.chromaticNumber_le (since := "2024-03-21")]
theorem chromaticNumber_le_card [Fintype α] (C : G.Coloring α) :
G.chromaticNumber ≤ Fintype.card α := C.colorable.chromaticNumber_le
#align simple_graph.chromatic_number_le_card SimpleGraph.chromaticNumber_le_card
theorem colorable_chromaticNumber {m : ℕ} (hc : G.Colorable m) :
G.Colorable (ENat.toNat G.chromaticNumber) := by
classical
rw [hc.chromaticNumber_eq_sInf, Nat.sInf_def]
· apply Nat.find_spec
· exact colorable_set_nonempty_of_colorable hc
#align simple_graph.colorable_chromatic_number SimpleGraph.colorable_chromaticNumber
theorem colorable_chromaticNumber_of_fintype (G : SimpleGraph V) [Finite V] :
G.Colorable (ENat.toNat G.chromaticNumber) := by
cases nonempty_fintype V
exact colorable_chromaticNumber G.colorable_of_fintype
#align simple_graph.colorable_chromatic_number_of_fintype SimpleGraph.colorable_chromaticNumber_of_fintype
theorem chromaticNumber_le_one_of_subsingleton (G : SimpleGraph V) [Subsingleton V] :
G.chromaticNumber ≤ 1 := by
rw [← Nat.cast_one, chromaticNumber_le_iff_colorable]
refine ⟨Coloring.mk (fun _ => 0) ?_⟩
intros v w
cases Subsingleton.elim v w
simp
#align simple_graph.chromatic_number_le_one_of_subsingleton SimpleGraph.chromaticNumber_le_one_of_subsingleton
theorem chromaticNumber_eq_zero_of_isempty (G : SimpleGraph V) [IsEmpty V] :
G.chromaticNumber = 0 := by
rw [← nonpos_iff_eq_zero, ← Nat.cast_zero, chromaticNumber_le_iff_colorable]
apply colorable_of_isEmpty
#align simple_graph.chromatic_number_eq_zero_of_isempty SimpleGraph.chromaticNumber_eq_zero_of_isempty
theorem isEmpty_of_chromaticNumber_eq_zero (G : SimpleGraph V) [Finite V]
(h : G.chromaticNumber = 0) : IsEmpty V := by
have h' := G.colorable_chromaticNumber_of_fintype
rw [h] at h'
exact G.isEmpty_of_colorable_zero h'
#align simple_graph.is_empty_of_chromatic_number_eq_zero SimpleGraph.isEmpty_of_chromaticNumber_eq_zero
theorem chromaticNumber_pos [Nonempty V] {n : ℕ} (hc : G.Colorable n) : 0 < G.chromaticNumber := by
rw [hc.chromaticNumber_eq_sInf, Nat.cast_pos]
apply le_csInf (colorable_set_nonempty_of_colorable hc)
intro m hm
by_contra h'
simp only [not_le] at h'
obtain ⟨i, hi⟩ := hm.some (Classical.arbitrary V)
have h₁: i < 0 := lt_of_lt_of_le hi (Nat.le_of_lt_succ h')
exact Nat.not_lt_zero _ h₁
#align simple_graph.chromatic_number_pos SimpleGraph.chromaticNumber_pos
theorem colorable_of_chromaticNumber_ne_top (h : G.chromaticNumber ≠ ⊤) :
G.Colorable (ENat.toNat G.chromaticNumber) := by
rw [chromaticNumber_ne_top_iff_exists] at h
obtain ⟨n, hn⟩ := h
exact colorable_chromaticNumber hn
#align simple_graph.colorable_of_chromatic_number_pos SimpleGraph.colorable_of_chromaticNumber_ne_top
theorem Colorable.mono_left {G' : SimpleGraph V} (h : G ≤ G') {n : ℕ} (hc : G'.Colorable n) :
G.Colorable n :=
⟨hc.some.comp (Hom.mapSpanningSubgraphs h)⟩
#align simple_graph.colorable.mono_left SimpleGraph.Colorable.mono_left
theorem chromaticNumber_le_of_forall_imp {V' : Type*} {G' : SimpleGraph V'}
(h : ∀ n, G'.Colorable n → G.Colorable n) :
G.chromaticNumber ≤ G'.chromaticNumber := by
rw [chromaticNumber, chromaticNumber]
simp only [Set.mem_setOf_eq, le_iInf_iff]
intro m hc
have := h _ hc
rw [← chromaticNumber_le_iff_colorable] at this
exact this
#align simple_graph.colorable.chromatic_number_le_of_forall_imp SimpleGraph.chromaticNumber_le_of_forall_imp
theorem chromaticNumber_mono (G' : SimpleGraph V)
(h : G ≤ G') : G.chromaticNumber ≤ G'.chromaticNumber :=
chromaticNumber_le_of_forall_imp fun _ => Colorable.mono_left h
#align simple_graph.colorable.chromatic_number_mono SimpleGraph.chromaticNumber_mono
theorem chromaticNumber_mono_of_embedding {V' : Type*} {G' : SimpleGraph V'}
(f : G ↪g G') : G.chromaticNumber ≤ G'.chromaticNumber :=
chromaticNumber_le_of_forall_imp fun _ => Colorable.of_embedding f
#align simple_graph.colorable.chromatic_number_mono_of_embedding SimpleGraph.chromaticNumber_mono_of_embedding
lemma card_le_chromaticNumber_iff_forall_surjective [Fintype α] :
card α ≤ G.chromaticNumber ↔ ∀ C : G.Coloring α, Surjective C := by
refine ⟨fun h C ↦ ?_, fun h ↦ ?_⟩
· rw [C.colorable.chromaticNumber_eq_sInf, Nat.cast_le] at h
intro i
by_contra! hi
let D : G.Coloring {a // a ≠ i} := ⟨fun v ↦ ⟨C v, hi v⟩, (C.valid · <| congr_arg Subtype.val ·)⟩
classical
exact Nat.not_mem_of_lt_sInf ((Nat.pred_lt' <| card_pos_iff.2 ⟨i⟩).trans_le h)
⟨G.recolorOfEquiv (equivOfCardEq <| by simp [Nat.pred_eq_sub_one]) D⟩
· simp only [chromaticNumber, Set.mem_setOf_eq, le_iInf_iff, Nat.cast_le, exists_prop]
rintro i ⟨C⟩
contrapose! h
refine ⟨G.recolorOfCardLE (by simpa using h.le) C, fun hC ↦ ?_⟩
dsimp at hC
simpa [h.not_le] using Fintype.card_le_of_surjective _ hC.of_comp
lemma le_chromaticNumber_iff_forall_surjective :
n ≤ G.chromaticNumber ↔ ∀ C : G.Coloring (Fin n), Surjective C := by
simp [← card_le_chromaticNumber_iff_forall_surjective]
lemma chromaticNumber_eq_card_iff_forall_surjective [Fintype α] (hG : G.Colorable (card α)) :
G.chromaticNumber = card α ↔ ∀ C : G.Coloring α, Surjective C := by
rw [← hG.chromaticNumber_le.ge_iff_eq, card_le_chromaticNumber_iff_forall_surjective]
#align simple_graph.chromatic_number_eq_card_of_forall_surj SimpleGraph.chromaticNumber_eq_card_iff_forall_surjective
lemma chromaticNumber_eq_iff_forall_surjective (hG : G.Colorable n) :
G.chromaticNumber = n ↔ ∀ C : G.Coloring (Fin n), Surjective C := by
rw [← hG.chromaticNumber_le.ge_iff_eq, le_chromaticNumber_iff_forall_surjective]
theorem chromaticNumber_bot [Nonempty V] : (⊥ : SimpleGraph V).chromaticNumber = 1 := by
have : (⊥ : SimpleGraph V).Colorable 1 := ⟨.mk 0 $ by simp⟩
exact this.chromaticNumber_le.antisymm $ ENat.one_le_iff_pos.2 $ chromaticNumber_pos this
#align simple_graph.chromatic_number_bot SimpleGraph.chromaticNumber_bot
@[simp]
theorem chromaticNumber_top [Fintype V] : (⊤ : SimpleGraph V).chromaticNumber = Fintype.card V := by
rw [chromaticNumber_eq_card_iff_forall_surjective (selfColoring _).colorable]
intro C
rw [← Finite.injective_iff_surjective]
intro v w
contrapose
intro h
exact C.valid h
#align simple_graph.chromatic_number_top SimpleGraph.chromaticNumber_top
theorem chromaticNumber_top_eq_top_of_infinite (V : Type*) [Infinite V] :
(⊤ : SimpleGraph V).chromaticNumber = ⊤ := by
by_contra hc
rw [← Ne, chromaticNumber_ne_top_iff_exists] at hc
obtain ⟨n, ⟨hn⟩⟩ := hc
exact not_injective_infinite_finite _ hn.injective_of_top_hom
#align simple_graph.chromatic_number_top_eq_zero_of_infinite SimpleGraph.chromaticNumber_top_eq_top_of_infinite
def CompleteBipartiteGraph.bicoloring (V W : Type*) : (completeBipartiteGraph V W).Coloring Bool :=
Coloring.mk (fun v => v.isRight)
(by
intro v w
cases v <;> cases w <;> simp)
#align simple_graph.complete_bipartite_graph.bicoloring SimpleGraph.CompleteBipartiteGraph.bicoloring
theorem CompleteBipartiteGraph.chromaticNumber {V W : Type*} [Nonempty V] [Nonempty W] :
(completeBipartiteGraph V W).chromaticNumber = 2 := by
rw [← Nat.cast_two, chromaticNumber_eq_iff_forall_surjective
(by simpa using (CompleteBipartiteGraph.bicoloring V W).colorable)]
intro C b
have v := Classical.arbitrary V
have w := Classical.arbitrary W
have h : (completeBipartiteGraph V W).Adj (Sum.inl v) (Sum.inr w) := by simp
by_cases he : C (Sum.inl v) = b
· exact ⟨_, he⟩
by_cases he' : C (Sum.inr w) = b
· exact ⟨_, he'⟩
· simpa using two_lt_card_iff.2 ⟨_, _, _, C.valid h, he, he'⟩
#align simple_graph.complete_bipartite_graph.chromatic_number SimpleGraph.CompleteBipartiteGraph.chromaticNumber
theorem IsClique.card_le_of_coloring {s : Finset V} (h : G.IsClique s) [Fintype α]
(C : G.Coloring α) : s.card ≤ Fintype.card α := by
rw [isClique_iff_induce_eq] at h
have f : G.induce ↑s ↪g G := Embedding.comap (Function.Embedding.subtype fun x => x ∈ ↑s) G
rw [h] at f
convert Fintype.card_le_of_injective _ (C.comp f.toHom).injective_of_top_hom using 1
simp
#align simple_graph.is_clique.card_le_of_coloring SimpleGraph.IsClique.card_le_of_coloring
theorem IsClique.card_le_of_colorable {s : Finset V} (h : G.IsClique s) {n : ℕ}
(hc : G.Colorable n) : s.card ≤ n := by
convert h.card_le_of_coloring hc.some
simp
#align simple_graph.is_clique.card_le_of_colorable SimpleGraph.IsClique.card_le_of_colorable
| Mathlib/Combinatorics/SimpleGraph/Coloring.lean | 481 | 491 | theorem IsClique.card_le_chromaticNumber {s : Finset V} (h : G.IsClique s) :
s.card ≤ G.chromaticNumber := by |
obtain (hc | hc) := eq_or_ne G.chromaticNumber ⊤
· rw [hc]
exact le_top
· have hc' := hc
rw [chromaticNumber_ne_top_iff_exists] at hc'
obtain ⟨n, c⟩ := hc'
rw [← ENat.coe_toNat_eq_self] at hc
rw [← hc, Nat.cast_le]
exact h.card_le_of_colorable (colorable_chromaticNumber c)
|
import Mathlib.Order.Filter.Ultrafilter
import Mathlib.Order.Filter.Germ
#align_import order.filter.filter_product from "leanprover-community/mathlib"@"2738d2ca56cbc63be80c3bd48e9ed90ad94e947d"
universe u v
variable {α : Type u} {β : Type v} {φ : Ultrafilter α}
open scoped Classical
namespace Filter
local notation3 "∀* "(...)", "r:(scoped p => Filter.Eventually p (Ultrafilter.toFilter φ)) => r
namespace Germ
open Ultrafilter
local notation "β*" => Germ (φ : Filter α) β
instance instGroupWithZero [GroupWithZero β] : GroupWithZero β* where
__ := instDivInvMonoid
__ := instMonoidWithZero
mul_inv_cancel f := inductionOn f fun f hf ↦ coe_eq.2 <| (φ.em fun y ↦ f y = 0).elim
(fun H ↦ (hf <| coe_eq.2 H).elim) fun H ↦ H.mono fun x ↦ mul_inv_cancel
inv_zero := coe_eq.2 <| by simp only [Function.comp, inv_zero, EventuallyEq.rfl]
instance instDivisionSemiring [DivisionSemiring β] : DivisionSemiring β* where
toSemiring := instSemiring
__ := instGroupWithZero
nnqsmul := _
instance instDivisionRing [DivisionRing β] : DivisionRing β* where
__ := instRing
__ := instDivisionSemiring
qsmul := _
instance instSemifield [Semifield β] : Semifield β* where
__ := instCommSemiring
__ := instDivisionSemiring
instance instField [Field β] : Field β* where
__ := instCommRing
__ := instDivisionRing
theorem coe_lt [Preorder β] {f g : α → β} : (f : β*) < g ↔ ∀* x, f x < g x := by
simp only [lt_iff_le_not_le, eventually_and, coe_le, eventually_not, EventuallyLE]
#align filter.germ.coe_lt Filter.Germ.coe_lt
theorem coe_pos [Preorder β] [Zero β] {f : α → β} : 0 < (f : β*) ↔ ∀* x, 0 < f x :=
coe_lt
#align filter.germ.coe_pos Filter.Germ.coe_pos
theorem const_lt [Preorder β] {x y : β} : x < y → (↑x : β*) < ↑y :=
coe_lt.mpr ∘ liftRel_const
#align filter.germ.const_lt Filter.Germ.const_lt
@[simp, norm_cast]
theorem const_lt_iff [Preorder β] {x y : β} : (↑x : β*) < ↑y ↔ x < y :=
coe_lt.trans liftRel_const_iff
#align filter.germ.const_lt_iff Filter.Germ.const_lt_iff
| Mathlib/Order/Filter/FilterProduct.lean | 82 | 84 | theorem lt_def [Preorder β] : ((· < ·) : β* → β* → Prop) = LiftRel (· < ·) := by |
ext ⟨f⟩ ⟨g⟩
exact coe_lt
|
import Mathlib.Order.Interval.Set.OrdConnected
import Mathlib.Data.Set.Lattice
#align_import data.set.intervals.ord_connected_component from "leanprover-community/mathlib"@"92ca63f0fb391a9ca5f22d2409a6080e786d99f7"
open Interval Function OrderDual
namespace Set
variable {α : Type*} [LinearOrder α] {s t : Set α} {x y z : α}
def ordConnectedComponent (s : Set α) (x : α) : Set α :=
{ y | [[x, y]] ⊆ s }
#align set.ord_connected_component Set.ordConnectedComponent
theorem mem_ordConnectedComponent : y ∈ ordConnectedComponent s x ↔ [[x, y]] ⊆ s :=
Iff.rfl
#align set.mem_ord_connected_component Set.mem_ordConnectedComponent
theorem dual_ordConnectedComponent :
ordConnectedComponent (ofDual ⁻¹' s) (toDual x) = ofDual ⁻¹' ordConnectedComponent s x :=
ext <| (Surjective.forall toDual.surjective).2 fun x => by
rw [mem_ordConnectedComponent, dual_uIcc]
rfl
#align set.dual_ord_connected_component Set.dual_ordConnectedComponent
theorem ordConnectedComponent_subset : ordConnectedComponent s x ⊆ s := fun _ hy =>
hy right_mem_uIcc
#align set.ord_connected_component_subset Set.ordConnectedComponent_subset
theorem subset_ordConnectedComponent {t} [h : OrdConnected s] (hs : x ∈ s) (ht : s ⊆ t) :
s ⊆ ordConnectedComponent t x := fun _ hy => (h.uIcc_subset hs hy).trans ht
#align set.subset_ord_connected_component Set.subset_ordConnectedComponent
@[simp]
theorem self_mem_ordConnectedComponent : x ∈ ordConnectedComponent s x ↔ x ∈ s := by
rw [mem_ordConnectedComponent, uIcc_self, singleton_subset_iff]
#align set.self_mem_ord_connected_component Set.self_mem_ordConnectedComponent
@[simp]
theorem nonempty_ordConnectedComponent : (ordConnectedComponent s x).Nonempty ↔ x ∈ s :=
⟨fun ⟨_, hy⟩ => hy <| left_mem_uIcc, fun h => ⟨x, self_mem_ordConnectedComponent.2 h⟩⟩
#align set.nonempty_ord_connected_component Set.nonempty_ordConnectedComponent
@[simp]
theorem ordConnectedComponent_eq_empty : ordConnectedComponent s x = ∅ ↔ x ∉ s := by
rw [← not_nonempty_iff_eq_empty, nonempty_ordConnectedComponent]
#align set.ord_connected_component_eq_empty Set.ordConnectedComponent_eq_empty
@[simp]
theorem ordConnectedComponent_empty : ordConnectedComponent ∅ x = ∅ :=
ordConnectedComponent_eq_empty.2 (not_mem_empty x)
#align set.ord_connected_component_empty Set.ordConnectedComponent_empty
@[simp]
theorem ordConnectedComponent_univ : ordConnectedComponent univ x = univ := by
simp [ordConnectedComponent]
#align set.ord_connected_component_univ Set.ordConnectedComponent_univ
theorem ordConnectedComponent_inter (s t : Set α) (x : α) :
ordConnectedComponent (s ∩ t) x = ordConnectedComponent s x ∩ ordConnectedComponent t x := by
simp [ordConnectedComponent, setOf_and]
#align set.ord_connected_component_inter Set.ordConnectedComponent_inter
| Mathlib/Order/Interval/Set/OrdConnectedComponent.lean | 82 | 84 | theorem mem_ordConnectedComponent_comm :
y ∈ ordConnectedComponent s x ↔ x ∈ ordConnectedComponent s y := by |
rw [mem_ordConnectedComponent, mem_ordConnectedComponent, uIcc_comm]
|
import Mathlib.RingTheory.Ideal.Operations
import Mathlib.Algebra.Module.Torsion
import Mathlib.Algebra.Ring.Idempotents
import Mathlib.LinearAlgebra.FiniteDimensional
import Mathlib.RingTheory.Ideal.LocalRing
import Mathlib.RingTheory.Filtration
import Mathlib.RingTheory.Nakayama
#align_import ring_theory.ideal.cotangent from "leanprover-community/mathlib"@"4b92a463033b5587bb011657e25e4710bfca7364"
namespace Ideal
-- Porting note: universes need to be explicit to avoid bad universe levels in `quotCotangent`
universe u v w
variable {R : Type u} {S : Type v} {S' : Type w} [CommRing R] [CommSemiring S] [Algebra S R]
variable [CommSemiring S'] [Algebra S' R] [Algebra S S'] [IsScalarTower S S' R] (I : Ideal R)
-- Porting note: instances that were derived automatically need to be proved by hand (see below)
def Cotangent : Type _ := I ⧸ (I • ⊤ : Submodule R I)
#align ideal.cotangent Ideal.Cotangent
instance : AddCommGroup I.Cotangent := by delta Cotangent; infer_instance
instance cotangentModule : Module (R ⧸ I) I.Cotangent := by delta Cotangent; infer_instance
instance : Inhabited I.Cotangent := ⟨0⟩
instance Cotangent.moduleOfTower : Module S I.Cotangent :=
Submodule.Quotient.module' _
#align ideal.cotangent.module_of_tower Ideal.Cotangent.moduleOfTower
instance Cotangent.isScalarTower : IsScalarTower S S' I.Cotangent :=
Submodule.Quotient.isScalarTower _ _
#align ideal.cotangent.is_scalar_tower Ideal.Cotangent.isScalarTower
instance [IsNoetherian R I] : IsNoetherian R I.Cotangent :=
inferInstanceAs (IsNoetherian R (I ⧸ (I • ⊤ : Submodule R I)))
@[simps! (config := .lemmasOnly) apply]
def toCotangent : I →ₗ[R] I.Cotangent := Submodule.mkQ _
#align ideal.to_cotangent Ideal.toCotangent
theorem map_toCotangent_ker : I.toCotangent.ker.map I.subtype = I ^ 2 := by
rw [Ideal.toCotangent, Submodule.ker_mkQ, pow_two, Submodule.map_smul'' I ⊤ (Submodule.subtype I),
Algebra.id.smul_eq_mul, Submodule.map_subtype_top]
#align ideal.map_to_cotangent_ker Ideal.map_toCotangent_ker
theorem mem_toCotangent_ker {x : I} : x ∈ LinearMap.ker I.toCotangent ↔ (x : R) ∈ I ^ 2 := by
rw [← I.map_toCotangent_ker]
simp
#align ideal.mem_to_cotangent_ker Ideal.mem_toCotangent_ker
theorem toCotangent_eq {x y : I} : I.toCotangent x = I.toCotangent y ↔ (x - y : R) ∈ I ^ 2 := by
rw [← sub_eq_zero]
exact I.mem_toCotangent_ker
#align ideal.to_cotangent_eq Ideal.toCotangent_eq
theorem toCotangent_eq_zero (x : I) : I.toCotangent x = 0 ↔ (x : R) ∈ I ^ 2 := I.mem_toCotangent_ker
#align ideal.to_cotangent_eq_zero Ideal.toCotangent_eq_zero
theorem toCotangent_surjective : Function.Surjective I.toCotangent := Submodule.mkQ_surjective _
#align ideal.to_cotangent_surjective Ideal.toCotangent_surjective
theorem toCotangent_range : LinearMap.range I.toCotangent = ⊤ := Submodule.range_mkQ _
#align ideal.to_cotangent_range Ideal.toCotangent_range
theorem cotangent_subsingleton_iff : Subsingleton I.Cotangent ↔ IsIdempotentElem I := by
constructor
· intro H
refine (pow_two I).symm.trans (le_antisymm (Ideal.pow_le_self two_ne_zero) ?_)
exact fun x hx => (I.toCotangent_eq_zero ⟨x, hx⟩).mp (Subsingleton.elim _ _)
· exact fun e =>
⟨fun x y =>
Quotient.inductionOn₂' x y fun x y =>
I.toCotangent_eq.mpr <| ((pow_two I).trans e).symm ▸ I.sub_mem x.prop y.prop⟩
#align ideal.cotangent_subsingleton_iff Ideal.cotangent_subsingleton_iff
def cotangentToQuotientSquare : I.Cotangent →ₗ[R] R ⧸ I ^ 2 :=
Submodule.mapQ (I • ⊤) (I ^ 2) I.subtype
(by
rw [← Submodule.map_le_iff_le_comap, Submodule.map_smul'', Submodule.map_top,
Submodule.range_subtype, smul_eq_mul, pow_two] )
#align ideal.cotangent_to_quotient_square Ideal.cotangentToQuotientSquare
theorem to_quotient_square_comp_toCotangent :
I.cotangentToQuotientSquare.comp I.toCotangent = (I ^ 2).mkQ.comp (Submodule.subtype I) :=
LinearMap.ext fun _ => rfl
#align ideal.to_quotient_square_comp_to_cotangent Ideal.to_quotient_square_comp_toCotangent
@[simp]
theorem toCotangent_to_quotient_square (x : I) :
I.cotangentToQuotientSquare (I.toCotangent x) = (I ^ 2).mkQ x := rfl
#align ideal.to_cotangent_to_quotient_square Ideal.toCotangent_to_quotient_square
def cotangentIdeal (I : Ideal R) : Ideal (R ⧸ I ^ 2) :=
Submodule.map (Quotient.mk (I ^ 2)|>.toSemilinearMap) I
#align ideal.cotangent_ideal Ideal.cotangentIdeal
theorem cotangentIdeal_square (I : Ideal R) : I.cotangentIdeal ^ 2 = ⊥ := by
rw [eq_bot_iff, pow_two I.cotangentIdeal, ← smul_eq_mul]
intro x hx
refine Submodule.smul_induction_on hx ?_ ?_
· rintro _ ⟨x, hx, rfl⟩ _ ⟨y, hy, rfl⟩; apply (Submodule.Quotient.eq _).mpr _
rw [sub_zero, pow_two]; exact Ideal.mul_mem_mul hx hy
· intro x y hx hy; exact add_mem hx hy
#align ideal.cotangent_ideal_square Ideal.cotangentIdeal_square
set_option backward.synthInstance.canonInstances false in -- See https://github.com/leanprover-community/mathlib4/issues/12532
theorem to_quotient_square_range :
LinearMap.range I.cotangentToQuotientSquare = I.cotangentIdeal.restrictScalars R := by
trans LinearMap.range (I.cotangentToQuotientSquare.comp I.toCotangent)
· rw [LinearMap.range_comp, I.toCotangent_range, Submodule.map_top]
· rw [to_quotient_square_comp_toCotangent, LinearMap.range_comp, I.range_subtype]; ext; rfl
#align ideal.to_quotient_square_range Ideal.to_quotient_square_range
set_option backward.synthInstance.canonInstances false in -- See https://github.com/leanprover-community/mathlib4/issues/12532
noncomputable def cotangentEquivIdeal : I.Cotangent ≃ₗ[R] I.cotangentIdeal := by
refine
{ LinearMap.codRestrict (I.cotangentIdeal.restrictScalars R) I.cotangentToQuotientSquare
fun x => by { rw [← to_quotient_square_range]; exact LinearMap.mem_range_self _ _ },
Equiv.ofBijective _ ⟨?_, ?_⟩ with }
· rintro x y e
replace e := congr_arg Subtype.val e
obtain ⟨x, rfl⟩ := I.toCotangent_surjective x
obtain ⟨y, rfl⟩ := I.toCotangent_surjective y
rw [I.toCotangent_eq]
dsimp only [toCotangent_to_quotient_square, Submodule.mkQ_apply] at e
rwa [Submodule.Quotient.eq] at e
· rintro ⟨_, x, hx, rfl⟩
exact ⟨I.toCotangent ⟨x, hx⟩, Subtype.ext rfl⟩
#align ideal.cotangent_equiv_ideal Ideal.cotangentEquivIdeal
@[simp]
theorem cotangentEquivIdeal_apply (x : I.Cotangent) :
↑(I.cotangentEquivIdeal x) = I.cotangentToQuotientSquare x := rfl
#align ideal.cotangent_equiv_ideal_apply Ideal.cotangentEquivIdeal_apply
theorem cotangentEquivIdeal_symm_apply (x : R) (hx : x ∈ I) :
-- Note: #8386 had to specify `(R₂ := R)` because `I.toCotangent` suggested `R ⧸ I^2` instead
I.cotangentEquivIdeal.symm ⟨(I ^ 2).mkQ x, Submodule.mem_map_of_mem (R₂ := R) hx⟩ =
I.toCotangent ⟨x, hx⟩ := by
apply I.cotangentEquivIdeal.injective
rw [I.cotangentEquivIdeal.apply_symm_apply]
ext
rfl
#align ideal.cotangent_equiv_ideal_symm_apply Ideal.cotangentEquivIdeal_symm_apply
variable {A B : Type*} [CommRing A] [CommRing B] [Algebra R A] [Algebra R B]
def _root_.AlgHom.kerSquareLift (f : A →ₐ[R] B) : A ⧸ RingHom.ker f.toRingHom ^ 2 →ₐ[R] B := by
refine { Ideal.Quotient.lift (RingHom.ker f.toRingHom ^ 2) f.toRingHom ?_ with commutes' := ?_ }
· intro a ha; exact Ideal.pow_le_self two_ne_zero ha
· intro r
rw [IsScalarTower.algebraMap_apply R A, RingHom.toFun_eq_coe, Ideal.Quotient.algebraMap_eq,
Ideal.Quotient.lift_mk]
exact f.map_algebraMap r
#align alg_hom.ker_square_lift AlgHom.kerSquareLift
| Mathlib/RingTheory/Ideal/Cotangent.lean | 185 | 189 | theorem _root_.AlgHom.ker_kerSquareLift (f : A →ₐ[R] B) :
RingHom.ker f.kerSquareLift.toRingHom = f.toRingHom.ker.cotangentIdeal := by |
apply le_antisymm
· intro x hx; obtain ⟨x, rfl⟩ := Ideal.Quotient.mk_surjective x; exact ⟨x, hx, rfl⟩
· rintro _ ⟨x, hx, rfl⟩; exact hx
|
import Mathlib.CategoryTheory.Limits.KanExtension
import Mathlib.Topology.Category.TopCat.Opens
import Mathlib.CategoryTheory.Adjunction.Unique
import Mathlib.Topology.Sheaves.Init
import Mathlib.Data.Set.Subsingleton
#align_import topology.sheaves.presheaf from "leanprover-community/mathlib"@"5dc6092d09e5e489106865241986f7f2ad28d4c8"
set_option autoImplicit true
universe w v u
open CategoryTheory TopologicalSpace Opposite
variable (C : Type u) [Category.{v} C]
namespace TopCat
-- Porting note(#5171): was @[nolint has_nonempty_instance]
def Presheaf (X : TopCat.{w}) : Type max u v w :=
(Opens X)ᵒᵖ ⥤ C
set_option linter.uppercaseLean3 false in
#align Top.presheaf TopCat.Presheaf
instance (X : TopCat.{w}) : Category (Presheaf.{w, v, u} C X) :=
inferInstanceAs (Category ((Opens X)ᵒᵖ ⥤ C : Type max u v w))
variable {C}
namespace Presheaf
@[simp] theorem comp_app {P Q R : Presheaf C X} (f : P ⟶ Q) (g : Q ⟶ R) :
(f ≫ g).app U = f.app U ≫ g.app U := rfl
-- Porting note (#10756): added an `ext` lemma,
-- since `NatTrans.ext` can not see through the definition of `Presheaf`.
-- See https://github.com/leanprover-community/mathlib4/issues/5229
@[ext]
lemma ext {P Q : Presheaf C X} {f g : P ⟶ Q} (w : ∀ U : Opens X, f.app (op U) = g.app (op U)) :
f = g := by
apply NatTrans.ext
ext U
induction U with | _ U => ?_
apply w
attribute [local instance] CategoryTheory.ConcreteCategory.hasCoeToSort
CategoryTheory.ConcreteCategory.instFunLike
macro "sheaf_restrict" : attr =>
`(attr|aesop safe 50 apply (rule_sets := [$(Lean.mkIdent `Restrict):ident]))
attribute [sheaf_restrict] bot_le le_top le_refl inf_le_left inf_le_right
le_sup_left le_sup_right
macro (name := restrict_tac) "restrict_tac" c:Aesop.tactic_clause* : tactic =>
`(tactic| first | assumption |
aesop $c*
(config := { terminal := true
assumptionTransparency := .reducible
enableSimp := false })
(rule_sets := [-default, -builtin, $(Lean.mkIdent `Restrict):ident]))
macro (name := restrict_tac?) "restrict_tac?" c:Aesop.tactic_clause* : tactic =>
`(tactic|
aesop? $c*
(config := { terminal := true
assumptionTransparency := .reducible
enableSimp := false
maxRuleApplications := 300 })
(rule_sets := [-default, -builtin, $(Lean.mkIdent `Restrict):ident]))
attribute[aesop 10% (rule_sets := [Restrict])] le_trans
attribute[aesop safe destruct (rule_sets := [Restrict])] Eq.trans_le
attribute[aesop safe -50 (rule_sets := [Restrict])] Aesop.BuiltinRules.assumption
example {X} [CompleteLattice X] (v : Nat → X) (w x y z : X) (e : v 0 = v 1) (_ : v 1 = v 2)
(h₀ : v 1 ≤ x) (_ : x ≤ z ⊓ w) (h₂ : x ≤ y ⊓ z) : v 0 ≤ y := by
restrict_tac
def restrict {X : TopCat} {C : Type*} [Category C] [ConcreteCategory C] {F : X.Presheaf C}
{V : Opens X} (x : F.obj (op V)) {U : Opens X} (h : U ⟶ V) : F.obj (op U) :=
F.map h.op x
set_option linter.uppercaseLean3 false in
#align Top.presheaf.restrict TopCat.Presheaf.restrict
scoped[AlgebraicGeometry] infixl:80 " |_ₕ " => TopCat.Presheaf.restrict
scoped[AlgebraicGeometry] notation:80 x " |_ₗ " U " ⟪" e "⟫ " =>
@TopCat.Presheaf.restrict _ _ _ _ _ _ x U (@homOfLE (Opens _) _ U _ e)
open AlgebraicGeometry
abbrev restrictOpen {X : TopCat} {C : Type*} [Category C] [ConcreteCategory C] {F : X.Presheaf C}
{V : Opens X} (x : F.obj (op V)) (U : Opens X)
(e : U ≤ V := by restrict_tac) :
F.obj (op U) :=
x |_ₗ U ⟪e⟫
set_option linter.uppercaseLean3 false in
#align Top.presheaf.restrict_open TopCat.Presheaf.restrictOpen
scoped[AlgebraicGeometry] infixl:80 " |_ " => TopCat.Presheaf.restrictOpen
-- Porting note: linter tells this lemma is no going to be picked up by the simplifier, hence
-- `@[simp]` is removed
theorem restrict_restrict {X : TopCat} {C : Type*} [Category C] [ConcreteCategory C]
{F : X.Presheaf C} {U V W : Opens X} (e₁ : U ≤ V) (e₂ : V ≤ W) (x : F.obj (op W)) :
x |_ V |_ U = x |_ U := by
delta restrictOpen restrict
rw [← comp_apply, ← Functor.map_comp]
rfl
set_option linter.uppercaseLean3 false in
#align Top.presheaf.restrict_restrict TopCat.Presheaf.restrict_restrict
-- Porting note: linter tells this lemma is no going to be picked up by the simplifier, hence
-- `@[simp]` is removed
theorem map_restrict {X : TopCat} {C : Type*} [Category C] [ConcreteCategory C]
{F G : X.Presheaf C} (e : F ⟶ G) {U V : Opens X} (h : U ≤ V) (x : F.obj (op V)) :
e.app _ (x |_ U) = e.app _ x |_ U := by
delta restrictOpen restrict
rw [← comp_apply, NatTrans.naturality, comp_apply]
set_option linter.uppercaseLean3 false in
#align Top.presheaf.map_restrict TopCat.Presheaf.map_restrict
def pushforwardObj {X Y : TopCat.{w}} (f : X ⟶ Y) (ℱ : X.Presheaf C) : Y.Presheaf C :=
(Opens.map f).op ⋙ ℱ
set_option linter.uppercaseLean3 false in
#align Top.presheaf.pushforward_obj TopCat.Presheaf.pushforwardObj
infixl:80 " _* " => pushforwardObj
@[simp]
theorem pushforwardObj_obj {X Y : TopCat.{w}} (f : X ⟶ Y) (ℱ : X.Presheaf C) (U : (Opens Y)ᵒᵖ) :
(f _* ℱ).obj U = ℱ.obj ((Opens.map f).op.obj U) :=
rfl
set_option linter.uppercaseLean3 false in
#align Top.presheaf.pushforward_obj_obj TopCat.Presheaf.pushforwardObj_obj
@[simp]
theorem pushforwardObj_map {X Y : TopCat.{w}} (f : X ⟶ Y) (ℱ : X.Presheaf C) {U V : (Opens Y)ᵒᵖ}
(i : U ⟶ V) : (f _* ℱ).map i = ℱ.map ((Opens.map f).op.map i) :=
rfl
set_option linter.uppercaseLean3 false in
#align Top.presheaf.pushforward_obj_map TopCat.Presheaf.pushforwardObj_map
def pushforwardEq {X Y : TopCat.{w}} {f g : X ⟶ Y} (h : f = g) (ℱ : X.Presheaf C) :
f _* ℱ ≅ g _* ℱ :=
isoWhiskerRight (NatIso.op (Opens.mapIso f g h).symm) ℱ
set_option linter.uppercaseLean3 false in
#align Top.presheaf.pushforward_eq TopCat.Presheaf.pushforwardEq
| Mathlib/Topology/Sheaves/Presheaf.lean | 196 | 197 | theorem pushforward_eq' {X Y : TopCat.{w}} {f g : X ⟶ Y} (h : f = g) (ℱ : X.Presheaf C) :
f _* ℱ = g _* ℱ := by | rw [h]
|
import Mathlib.Init.Function
#align_import data.option.n_ary from "leanprover-community/mathlib"@"995b47e555f1b6297c7cf16855f1023e355219fb"
universe u
open Function
namespace Option
variable {α β γ δ : Type*} {f : α → β → γ} {a : Option α} {b : Option β} {c : Option γ}
def map₂ (f : α → β → γ) (a : Option α) (b : Option β) : Option γ :=
a.bind fun a => b.map <| f a
#align option.map₂ Option.map₂
theorem map₂_def {α β γ : Type u} (f : α → β → γ) (a : Option α) (b : Option β) :
map₂ f a b = f <$> a <*> b := by
cases a <;> rfl
#align option.map₂_def Option.map₂_def
-- Porting note (#10618): In Lean3, was `@[simp]` but now `simp` can prove it
theorem map₂_some_some (f : α → β → γ) (a : α) (b : β) : map₂ f (some a) (some b) = f a b := rfl
#align option.map₂_some_some Option.map₂_some_some
theorem map₂_coe_coe (f : α → β → γ) (a : α) (b : β) : map₂ f a b = f a b := rfl
#align option.map₂_coe_coe Option.map₂_coe_coe
@[simp]
theorem map₂_none_left (f : α → β → γ) (b : Option β) : map₂ f none b = none := rfl
#align option.map₂_none_left Option.map₂_none_left
@[simp]
| Mathlib/Data/Option/NAry.lean | 63 | 63 | theorem map₂_none_right (f : α → β → γ) (a : Option α) : map₂ f a none = none := by | cases a <;> rfl
|
import Mathlib.MeasureTheory.Integral.Lebesgue
open Set hiding restrict restrict_apply
open Filter ENNReal NNReal MeasureTheory.Measure
namespace MeasureTheory
variable {α : Type*} {m0 : MeasurableSpace α} {μ : Measure α}
noncomputable
def Measure.withDensity {m : MeasurableSpace α} (μ : Measure α) (f : α → ℝ≥0∞) : Measure α :=
Measure.ofMeasurable (fun s _ => ∫⁻ a in s, f a ∂μ) (by simp) fun s hs hd =>
lintegral_iUnion hs hd _
#align measure_theory.measure.with_density MeasureTheory.Measure.withDensity
@[simp]
theorem withDensity_apply (f : α → ℝ≥0∞) {s : Set α} (hs : MeasurableSet s) :
μ.withDensity f s = ∫⁻ a in s, f a ∂μ :=
Measure.ofMeasurable_apply s hs
#align measure_theory.with_density_apply MeasureTheory.withDensity_apply
theorem withDensity_apply_le (f : α → ℝ≥0∞) (s : Set α) :
∫⁻ a in s, f a ∂μ ≤ μ.withDensity f s := by
let t := toMeasurable (μ.withDensity f) s
calc
∫⁻ a in s, f a ∂μ ≤ ∫⁻ a in t, f a ∂μ :=
lintegral_mono_set (subset_toMeasurable (withDensity μ f) s)
_ = μ.withDensity f t :=
(withDensity_apply f (measurableSet_toMeasurable (withDensity μ f) s)).symm
_ = μ.withDensity f s := measure_toMeasurable s
theorem withDensity_apply' [SFinite μ] (f : α → ℝ≥0∞) (s : Set α) :
μ.withDensity f s = ∫⁻ a in s, f a ∂μ := by
apply le_antisymm ?_ (withDensity_apply_le f s)
let t := toMeasurable μ s
calc
μ.withDensity f s ≤ μ.withDensity f t := measure_mono (subset_toMeasurable μ s)
_ = ∫⁻ a in t, f a ∂μ := withDensity_apply f (measurableSet_toMeasurable μ s)
_ = ∫⁻ a in s, f a ∂μ := by congr 1; exact restrict_toMeasurable_of_sFinite s
@[simp]
lemma withDensity_zero_left (f : α → ℝ≥0∞) : (0 : Measure α).withDensity f = 0 := by
ext s hs
rw [withDensity_apply _ hs]
simp
theorem withDensity_congr_ae {f g : α → ℝ≥0∞} (h : f =ᵐ[μ] g) :
μ.withDensity f = μ.withDensity g := by
refine Measure.ext fun s hs => ?_
rw [withDensity_apply _ hs, withDensity_apply _ hs]
exact lintegral_congr_ae (ae_restrict_of_ae h)
#align measure_theory.with_density_congr_ae MeasureTheory.withDensity_congr_ae
lemma withDensity_mono {f g : α → ℝ≥0∞} (hfg : f ≤ᵐ[μ] g) :
μ.withDensity f ≤ μ.withDensity g := by
refine le_iff.2 fun s hs ↦ ?_
rw [withDensity_apply _ hs, withDensity_apply _ hs]
refine set_lintegral_mono_ae' hs ?_
filter_upwards [hfg] with x h_le using fun _ ↦ h_le
theorem withDensity_add_left {f : α → ℝ≥0∞} (hf : Measurable f) (g : α → ℝ≥0∞) :
μ.withDensity (f + g) = μ.withDensity f + μ.withDensity g := by
refine Measure.ext fun s hs => ?_
rw [withDensity_apply _ hs, Measure.add_apply, withDensity_apply _ hs, withDensity_apply _ hs,
← lintegral_add_left hf]
simp only [Pi.add_apply]
#align measure_theory.with_density_add_left MeasureTheory.withDensity_add_left
theorem withDensity_add_right (f : α → ℝ≥0∞) {g : α → ℝ≥0∞} (hg : Measurable g) :
μ.withDensity (f + g) = μ.withDensity f + μ.withDensity g := by
simpa only [add_comm] using withDensity_add_left hg f
#align measure_theory.with_density_add_right MeasureTheory.withDensity_add_right
theorem withDensity_add_measure {m : MeasurableSpace α} (μ ν : Measure α) (f : α → ℝ≥0∞) :
(μ + ν).withDensity f = μ.withDensity f + ν.withDensity f := by
ext1 s hs
simp only [withDensity_apply f hs, restrict_add, lintegral_add_measure, Measure.add_apply]
#align measure_theory.with_density_add_measure MeasureTheory.withDensity_add_measure
| Mathlib/MeasureTheory/Measure/WithDensity.lean | 116 | 119 | theorem withDensity_sum {ι : Type*} {m : MeasurableSpace α} (μ : ι → Measure α) (f : α → ℝ≥0∞) :
(sum μ).withDensity f = sum fun n => (μ n).withDensity f := by |
ext1 s hs
simp_rw [sum_apply _ hs, withDensity_apply f hs, restrict_sum μ hs, lintegral_sum_measure]
|
import Mathlib.Algebra.Order.Ring.Defs
import Mathlib.Algebra.Group.Int
import Mathlib.Data.Nat.Dist
import Mathlib.Data.Ordmap.Ordnode
import Mathlib.Tactic.Abel
import Mathlib.Tactic.Linarith
#align_import data.ordmap.ordset from "leanprover-community/mathlib"@"47b51515e69f59bca5cf34ef456e6000fe205a69"
variable {α : Type*}
namespace Ordnode
theorem not_le_delta {s} (H : 1 ≤ s) : ¬s ≤ delta * 0 :=
not_le_of_gt H
#align ordnode.not_le_delta Ordnode.not_le_delta
theorem delta_lt_false {a b : ℕ} (h₁ : delta * a < b) (h₂ : delta * b < a) : False :=
not_le_of_lt (lt_trans ((mul_lt_mul_left (by decide)).2 h₁) h₂) <| by
simpa [mul_assoc] using Nat.mul_le_mul_right a (by decide : 1 ≤ delta * delta)
#align ordnode.delta_lt_false Ordnode.delta_lt_false
def realSize : Ordnode α → ℕ
| nil => 0
| node _ l _ r => realSize l + realSize r + 1
#align ordnode.real_size Ordnode.realSize
def Sized : Ordnode α → Prop
| nil => True
| node s l _ r => s = size l + size r + 1 ∧ Sized l ∧ Sized r
#align ordnode.sized Ordnode.Sized
theorem Sized.node' {l x r} (hl : @Sized α l) (hr : Sized r) : Sized (node' l x r) :=
⟨rfl, hl, hr⟩
#align ordnode.sized.node' Ordnode.Sized.node'
theorem Sized.eq_node' {s l x r} (h : @Sized α (node s l x r)) : node s l x r = .node' l x r := by
rw [h.1]
#align ordnode.sized.eq_node' Ordnode.Sized.eq_node'
theorem Sized.size_eq {s l x r} (H : Sized (@node α s l x r)) :
size (@node α s l x r) = size l + size r + 1 :=
H.1
#align ordnode.sized.size_eq Ordnode.Sized.size_eq
@[elab_as_elim]
theorem Sized.induction {t} (hl : @Sized α t) {C : Ordnode α → Prop} (H0 : C nil)
(H1 : ∀ l x r, C l → C r → C (.node' l x r)) : C t := by
induction t with
| nil => exact H0
| node _ _ _ _ t_ih_l t_ih_r =>
rw [hl.eq_node']
exact H1 _ _ _ (t_ih_l hl.2.1) (t_ih_r hl.2.2)
#align ordnode.sized.induction Ordnode.Sized.induction
theorem size_eq_realSize : ∀ {t : Ordnode α}, Sized t → size t = realSize t
| nil, _ => rfl
| node s l x r, ⟨h₁, h₂, h₃⟩ => by
rw [size, h₁, size_eq_realSize h₂, size_eq_realSize h₃]; rfl
#align ordnode.size_eq_real_size Ordnode.size_eq_realSize
@[simp]
theorem Sized.size_eq_zero {t : Ordnode α} (ht : Sized t) : size t = 0 ↔ t = nil := by
cases t <;> [simp;simp [ht.1]]
#align ordnode.sized.size_eq_zero Ordnode.Sized.size_eq_zero
theorem Sized.pos {s l x r} (h : Sized (@node α s l x r)) : 0 < s := by
rw [h.1]; apply Nat.le_add_left
#align ordnode.sized.pos Ordnode.Sized.pos
theorem dual_dual : ∀ t : Ordnode α, dual (dual t) = t
| nil => rfl
| node s l x r => by rw [dual, dual, dual_dual l, dual_dual r]
#align ordnode.dual_dual Ordnode.dual_dual
@[simp]
theorem size_dual (t : Ordnode α) : size (dual t) = size t := by cases t <;> rfl
#align ordnode.size_dual Ordnode.size_dual
def BalancedSz (l r : ℕ) : Prop :=
l + r ≤ 1 ∨ l ≤ delta * r ∧ r ≤ delta * l
#align ordnode.balanced_sz Ordnode.BalancedSz
instance BalancedSz.dec : DecidableRel BalancedSz := fun _ _ => Or.decidable
#align ordnode.balanced_sz.dec Ordnode.BalancedSz.dec
def Balanced : Ordnode α → Prop
| nil => True
| node _ l _ r => BalancedSz (size l) (size r) ∧ Balanced l ∧ Balanced r
#align ordnode.balanced Ordnode.Balanced
instance Balanced.dec : DecidablePred (@Balanced α)
| nil => by
unfold Balanced
infer_instance
| node _ l _ r => by
unfold Balanced
haveI := Balanced.dec l
haveI := Balanced.dec r
infer_instance
#align ordnode.balanced.dec Ordnode.Balanced.dec
@[symm]
theorem BalancedSz.symm {l r : ℕ} : BalancedSz l r → BalancedSz r l :=
Or.imp (by rw [add_comm]; exact id) And.symm
#align ordnode.balanced_sz.symm Ordnode.BalancedSz.symm
theorem balancedSz_zero {l : ℕ} : BalancedSz l 0 ↔ l ≤ 1 := by
simp (config := { contextual := true }) [BalancedSz]
#align ordnode.balanced_sz_zero Ordnode.balancedSz_zero
theorem balancedSz_up {l r₁ r₂ : ℕ} (h₁ : r₁ ≤ r₂) (h₂ : l + r₂ ≤ 1 ∨ r₂ ≤ delta * l)
(H : BalancedSz l r₁) : BalancedSz l r₂ := by
refine or_iff_not_imp_left.2 fun h => ?_
refine ⟨?_, h₂.resolve_left h⟩
cases H with
| inl H =>
cases r₂
· cases h (le_trans (Nat.add_le_add_left (Nat.zero_le _) _) H)
· exact le_trans (le_trans (Nat.le_add_right _ _) H) (Nat.le_add_left 1 _)
| inr H =>
exact le_trans H.1 (Nat.mul_le_mul_left _ h₁)
#align ordnode.balanced_sz_up Ordnode.balancedSz_up
theorem balancedSz_down {l r₁ r₂ : ℕ} (h₁ : r₁ ≤ r₂) (h₂ : l + r₂ ≤ 1 ∨ l ≤ delta * r₁)
(H : BalancedSz l r₂) : BalancedSz l r₁ :=
have : l + r₂ ≤ 1 → BalancedSz l r₁ := fun H => Or.inl (le_trans (Nat.add_le_add_left h₁ _) H)
Or.casesOn H this fun H => Or.casesOn h₂ this fun h₂ => Or.inr ⟨h₂, le_trans h₁ H.2⟩
#align ordnode.balanced_sz_down Ordnode.balancedSz_down
theorem Balanced.dual : ∀ {t : Ordnode α}, Balanced t → Balanced (dual t)
| nil, _ => ⟨⟩
| node _ l _ r, ⟨b, bl, br⟩ => ⟨by rw [size_dual, size_dual]; exact b.symm, br.dual, bl.dual⟩
#align ordnode.balanced.dual Ordnode.Balanced.dual
def node3L (l : Ordnode α) (x : α) (m : Ordnode α) (y : α) (r : Ordnode α) : Ordnode α :=
node' (node' l x m) y r
#align ordnode.node3_l Ordnode.node3L
def node3R (l : Ordnode α) (x : α) (m : Ordnode α) (y : α) (r : Ordnode α) : Ordnode α :=
node' l x (node' m y r)
#align ordnode.node3_r Ordnode.node3R
def node4L : Ordnode α → α → Ordnode α → α → Ordnode α → Ordnode α
| l, x, node _ ml y mr, z, r => node' (node' l x ml) y (node' mr z r)
| l, x, nil, z, r => node3L l x nil z r
#align ordnode.node4_l Ordnode.node4L
-- should not happen
def node4R : Ordnode α → α → Ordnode α → α → Ordnode α → Ordnode α
| l, x, node _ ml y mr, z, r => node' (node' l x ml) y (node' mr z r)
| l, x, nil, z, r => node3R l x nil z r
#align ordnode.node4_r Ordnode.node4R
-- should not happen
def rotateL : Ordnode α → α → Ordnode α → Ordnode α
| l, x, node _ m y r => if size m < ratio * size r then node3L l x m y r else node4L l x m y r
| l, x, nil => node' l x nil
#align ordnode.rotate_l Ordnode.rotateL
-- Porting note (#11467): during the port we marked these lemmas with `@[eqns]`
-- to emulate the old Lean 3 behaviour.
theorem rotateL_node (l : Ordnode α) (x : α) (sz : ℕ) (m : Ordnode α) (y : α) (r : Ordnode α) :
rotateL l x (node sz m y r) =
if size m < ratio * size r then node3L l x m y r else node4L l x m y r :=
rfl
theorem rotateL_nil (l : Ordnode α) (x : α) : rotateL l x nil = node' l x nil :=
rfl
-- should not happen
def rotateR : Ordnode α → α → Ordnode α → Ordnode α
| node _ l x m, y, r => if size m < ratio * size l then node3R l x m y r else node4R l x m y r
| nil, y, r => node' nil y r
#align ordnode.rotate_r Ordnode.rotateR
-- Porting note (#11467): during the port we marked these lemmas with `@[eqns]`
-- to emulate the old Lean 3 behaviour.
theorem rotateR_node (sz : ℕ) (l : Ordnode α) (x : α) (m : Ordnode α) (y : α) (r : Ordnode α) :
rotateR (node sz l x m) y r =
if size m < ratio * size l then node3R l x m y r else node4R l x m y r :=
rfl
theorem rotateR_nil (y : α) (r : Ordnode α) : rotateR nil y r = node' nil y r :=
rfl
-- should not happen
def balanceL' (l : Ordnode α) (x : α) (r : Ordnode α) : Ordnode α :=
if size l + size r ≤ 1 then node' l x r
else if size l > delta * size r then rotateR l x r else node' l x r
#align ordnode.balance_l' Ordnode.balanceL'
def balanceR' (l : Ordnode α) (x : α) (r : Ordnode α) : Ordnode α :=
if size l + size r ≤ 1 then node' l x r
else if size r > delta * size l then rotateL l x r else node' l x r
#align ordnode.balance_r' Ordnode.balanceR'
def balance' (l : Ordnode α) (x : α) (r : Ordnode α) : Ordnode α :=
if size l + size r ≤ 1 then node' l x r
else
if size r > delta * size l then rotateL l x r
else if size l > delta * size r then rotateR l x r else node' l x r
#align ordnode.balance' Ordnode.balance'
theorem dual_node' (l : Ordnode α) (x : α) (r : Ordnode α) :
dual (node' l x r) = node' (dual r) x (dual l) := by simp [node', add_comm]
#align ordnode.dual_node' Ordnode.dual_node'
theorem dual_node3L (l : Ordnode α) (x : α) (m : Ordnode α) (y : α) (r : Ordnode α) :
dual (node3L l x m y r) = node3R (dual r) y (dual m) x (dual l) := by
simp [node3L, node3R, dual_node', add_comm]
#align ordnode.dual_node3_l Ordnode.dual_node3L
theorem dual_node3R (l : Ordnode α) (x : α) (m : Ordnode α) (y : α) (r : Ordnode α) :
dual (node3R l x m y r) = node3L (dual r) y (dual m) x (dual l) := by
simp [node3L, node3R, dual_node', add_comm]
#align ordnode.dual_node3_r Ordnode.dual_node3R
theorem dual_node4L (l : Ordnode α) (x : α) (m : Ordnode α) (y : α) (r : Ordnode α) :
dual (node4L l x m y r) = node4R (dual r) y (dual m) x (dual l) := by
cases m <;> simp [node4L, node4R, node3R, dual_node3L, dual_node', add_comm]
#align ordnode.dual_node4_l Ordnode.dual_node4L
theorem dual_node4R (l : Ordnode α) (x : α) (m : Ordnode α) (y : α) (r : Ordnode α) :
dual (node4R l x m y r) = node4L (dual r) y (dual m) x (dual l) := by
cases m <;> simp [node4L, node4R, node3L, dual_node3R, dual_node', add_comm]
#align ordnode.dual_node4_r Ordnode.dual_node4R
theorem dual_rotateL (l : Ordnode α) (x : α) (r : Ordnode α) :
dual (rotateL l x r) = rotateR (dual r) x (dual l) := by
cases r <;> simp [rotateL, rotateR, dual_node']; split_ifs <;>
simp [dual_node3L, dual_node4L, node3R, add_comm]
#align ordnode.dual_rotate_l Ordnode.dual_rotateL
theorem dual_rotateR (l : Ordnode α) (x : α) (r : Ordnode α) :
dual (rotateR l x r) = rotateL (dual r) x (dual l) := by
rw [← dual_dual (rotateL _ _ _), dual_rotateL, dual_dual, dual_dual]
#align ordnode.dual_rotate_r Ordnode.dual_rotateR
theorem dual_balance' (l : Ordnode α) (x : α) (r : Ordnode α) :
dual (balance' l x r) = balance' (dual r) x (dual l) := by
simp [balance', add_comm]; split_ifs with h h_1 h_2 <;>
simp [dual_node', dual_rotateL, dual_rotateR, add_comm]
cases delta_lt_false h_1 h_2
#align ordnode.dual_balance' Ordnode.dual_balance'
theorem dual_balanceL (l : Ordnode α) (x : α) (r : Ordnode α) :
dual (balanceL l x r) = balanceR (dual r) x (dual l) := by
unfold balanceL balanceR
cases' r with rs rl rx rr
· cases' l with ls ll lx lr; · rfl
cases' ll with lls lll llx llr <;> cases' lr with lrs lrl lrx lrr <;> dsimp only [dual, id] <;>
try rfl
split_ifs with h <;> repeat simp [h, add_comm]
· cases' l with ls ll lx lr; · rfl
dsimp only [dual, id]
split_ifs; swap; · simp [add_comm]
cases' ll with lls lll llx llr <;> cases' lr with lrs lrl lrx lrr <;> try rfl
dsimp only [dual, id]
split_ifs with h <;> simp [h, add_comm]
#align ordnode.dual_balance_l Ordnode.dual_balanceL
theorem dual_balanceR (l : Ordnode α) (x : α) (r : Ordnode α) :
dual (balanceR l x r) = balanceL (dual r) x (dual l) := by
rw [← dual_dual (balanceL _ _ _), dual_balanceL, dual_dual, dual_dual]
#align ordnode.dual_balance_r Ordnode.dual_balanceR
theorem Sized.node3L {l x m y r} (hl : @Sized α l) (hm : Sized m) (hr : Sized r) :
Sized (node3L l x m y r) :=
(hl.node' hm).node' hr
#align ordnode.sized.node3_l Ordnode.Sized.node3L
theorem Sized.node3R {l x m y r} (hl : @Sized α l) (hm : Sized m) (hr : Sized r) :
Sized (node3R l x m y r) :=
hl.node' (hm.node' hr)
#align ordnode.sized.node3_r Ordnode.Sized.node3R
theorem Sized.node4L {l x m y r} (hl : @Sized α l) (hm : Sized m) (hr : Sized r) :
Sized (node4L l x m y r) := by
cases m <;> [exact (hl.node' hm).node' hr; exact (hl.node' hm.2.1).node' (hm.2.2.node' hr)]
#align ordnode.sized.node4_l Ordnode.Sized.node4L
theorem node3L_size {l x m y r} : size (@node3L α l x m y r) = size l + size m + size r + 2 := by
dsimp [node3L, node', size]; rw [add_right_comm _ 1]
#align ordnode.node3_l_size Ordnode.node3L_size
theorem node3R_size {l x m y r} : size (@node3R α l x m y r) = size l + size m + size r + 2 := by
dsimp [node3R, node', size]; rw [← add_assoc, ← add_assoc]
#align ordnode.node3_r_size Ordnode.node3R_size
theorem node4L_size {l x m y r} (hm : Sized m) :
size (@node4L α l x m y r) = size l + size m + size r + 2 := by
cases m <;> simp [node4L, node3L, node'] <;> [abel; (simp [size, hm.1]; abel)]
#align ordnode.node4_l_size Ordnode.node4L_size
theorem Sized.dual : ∀ {t : Ordnode α}, Sized t → Sized (dual t)
| nil, _ => ⟨⟩
| node _ l _ r, ⟨rfl, sl, sr⟩ => ⟨by simp [size_dual, add_comm], Sized.dual sr, Sized.dual sl⟩
#align ordnode.sized.dual Ordnode.Sized.dual
theorem Sized.dual_iff {t : Ordnode α} : Sized (.dual t) ↔ Sized t :=
⟨fun h => by rw [← dual_dual t]; exact h.dual, Sized.dual⟩
#align ordnode.sized.dual_iff Ordnode.Sized.dual_iff
theorem Sized.rotateL {l x r} (hl : @Sized α l) (hr : Sized r) : Sized (rotateL l x r) := by
cases r; · exact hl.node' hr
rw [Ordnode.rotateL_node]; split_ifs
· exact hl.node3L hr.2.1 hr.2.2
· exact hl.node4L hr.2.1 hr.2.2
#align ordnode.sized.rotate_l Ordnode.Sized.rotateL
theorem Sized.rotateR {l x r} (hl : @Sized α l) (hr : Sized r) : Sized (rotateR l x r) :=
Sized.dual_iff.1 <| by rw [dual_rotateR]; exact hr.dual.rotateL hl.dual
#align ordnode.sized.rotate_r Ordnode.Sized.rotateR
theorem Sized.rotateL_size {l x r} (hm : Sized r) :
size (@Ordnode.rotateL α l x r) = size l + size r + 1 := by
cases r <;> simp [Ordnode.rotateL]
simp only [hm.1]
split_ifs <;> simp [node3L_size, node4L_size hm.2.1] <;> abel
#align ordnode.sized.rotate_l_size Ordnode.Sized.rotateL_size
theorem Sized.rotateR_size {l x r} (hl : Sized l) :
size (@Ordnode.rotateR α l x r) = size l + size r + 1 := by
rw [← size_dual, dual_rotateR, hl.dual.rotateL_size, size_dual, size_dual, add_comm (size l)]
#align ordnode.sized.rotate_r_size Ordnode.Sized.rotateR_size
theorem Sized.balance' {l x r} (hl : @Sized α l) (hr : Sized r) : Sized (balance' l x r) := by
unfold balance'; split_ifs
· exact hl.node' hr
· exact hl.rotateL hr
· exact hl.rotateR hr
· exact hl.node' hr
#align ordnode.sized.balance' Ordnode.Sized.balance'
theorem size_balance' {l x r} (hl : @Sized α l) (hr : Sized r) :
size (@balance' α l x r) = size l + size r + 1 := by
unfold balance'; split_ifs
· rfl
· exact hr.rotateL_size
· exact hl.rotateR_size
· rfl
#align ordnode.size_balance' Ordnode.size_balance'
theorem All.imp {P Q : α → Prop} (H : ∀ a, P a → Q a) : ∀ {t}, All P t → All Q t
| nil, _ => ⟨⟩
| node _ _ _ _, ⟨h₁, h₂, h₃⟩ => ⟨h₁.imp H, H _ h₂, h₃.imp H⟩
#align ordnode.all.imp Ordnode.All.imp
theorem Any.imp {P Q : α → Prop} (H : ∀ a, P a → Q a) : ∀ {t}, Any P t → Any Q t
| nil => id
| node _ _ _ _ => Or.imp (Any.imp H) <| Or.imp (H _) (Any.imp H)
#align ordnode.any.imp Ordnode.Any.imp
theorem all_singleton {P : α → Prop} {x : α} : All P (singleton x) ↔ P x :=
⟨fun h => h.2.1, fun h => ⟨⟨⟩, h, ⟨⟩⟩⟩
#align ordnode.all_singleton Ordnode.all_singleton
theorem any_singleton {P : α → Prop} {x : α} : Any P (singleton x) ↔ P x :=
⟨by rintro (⟨⟨⟩⟩ | h | ⟨⟨⟩⟩); exact h, fun h => Or.inr (Or.inl h)⟩
#align ordnode.any_singleton Ordnode.any_singleton
theorem all_dual {P : α → Prop} : ∀ {t : Ordnode α}, All P (dual t) ↔ All P t
| nil => Iff.rfl
| node _ _l _x _r =>
⟨fun ⟨hr, hx, hl⟩ => ⟨all_dual.1 hl, hx, all_dual.1 hr⟩, fun ⟨hl, hx, hr⟩ =>
⟨all_dual.2 hr, hx, all_dual.2 hl⟩⟩
#align ordnode.all_dual Ordnode.all_dual
theorem all_iff_forall {P : α → Prop} : ∀ {t}, All P t ↔ ∀ x, Emem x t → P x
| nil => (iff_true_intro <| by rintro _ ⟨⟩).symm
| node _ l x r => by simp [All, Emem, all_iff_forall, Any, or_imp, forall_and]
#align ordnode.all_iff_forall Ordnode.all_iff_forall
theorem any_iff_exists {P : α → Prop} : ∀ {t}, Any P t ↔ ∃ x, Emem x t ∧ P x
| nil => ⟨by rintro ⟨⟩, by rintro ⟨_, ⟨⟩, _⟩⟩
| node _ l x r => by simp only [Emem]; simp [Any, any_iff_exists, or_and_right, exists_or]
#align ordnode.any_iff_exists Ordnode.any_iff_exists
theorem emem_iff_all {x : α} {t} : Emem x t ↔ ∀ P, All P t → P x :=
⟨fun h _ al => all_iff_forall.1 al _ h, fun H => H _ <| all_iff_forall.2 fun _ => id⟩
#align ordnode.emem_iff_all Ordnode.emem_iff_all
theorem all_node' {P l x r} : @All α P (node' l x r) ↔ All P l ∧ P x ∧ All P r :=
Iff.rfl
#align ordnode.all_node' Ordnode.all_node'
theorem all_node3L {P l x m y r} :
@All α P (node3L l x m y r) ↔ All P l ∧ P x ∧ All P m ∧ P y ∧ All P r := by
simp [node3L, all_node', and_assoc]
#align ordnode.all_node3_l Ordnode.all_node3L
theorem all_node3R {P l x m y r} :
@All α P (node3R l x m y r) ↔ All P l ∧ P x ∧ All P m ∧ P y ∧ All P r :=
Iff.rfl
#align ordnode.all_node3_r Ordnode.all_node3R
theorem all_node4L {P l x m y r} :
@All α P (node4L l x m y r) ↔ All P l ∧ P x ∧ All P m ∧ P y ∧ All P r := by
cases m <;> simp [node4L, all_node', All, all_node3L, and_assoc]
#align ordnode.all_node4_l Ordnode.all_node4L
theorem all_node4R {P l x m y r} :
@All α P (node4R l x m y r) ↔ All P l ∧ P x ∧ All P m ∧ P y ∧ All P r := by
cases m <;> simp [node4R, all_node', All, all_node3R, and_assoc]
#align ordnode.all_node4_r Ordnode.all_node4R
theorem all_rotateL {P l x r} : @All α P (rotateL l x r) ↔ All P l ∧ P x ∧ All P r := by
cases r <;> simp [rotateL, all_node']; split_ifs <;>
simp [all_node3L, all_node4L, All, and_assoc]
#align ordnode.all_rotate_l Ordnode.all_rotateL
theorem all_rotateR {P l x r} : @All α P (rotateR l x r) ↔ All P l ∧ P x ∧ All P r := by
rw [← all_dual, dual_rotateR, all_rotateL]; simp [all_dual, and_comm, and_left_comm, and_assoc]
#align ordnode.all_rotate_r Ordnode.all_rotateR
theorem all_balance' {P l x r} : @All α P (balance' l x r) ↔ All P l ∧ P x ∧ All P r := by
rw [balance']; split_ifs <;> simp [all_node', all_rotateL, all_rotateR]
#align ordnode.all_balance' Ordnode.all_balance'
theorem foldr_cons_eq_toList : ∀ (t : Ordnode α) (r : List α), t.foldr List.cons r = toList t ++ r
| nil, r => rfl
| node _ l x r, r' => by
rw [foldr, foldr_cons_eq_toList l, foldr_cons_eq_toList r, ← List.cons_append,
← List.append_assoc, ← foldr_cons_eq_toList l]; rfl
#align ordnode.foldr_cons_eq_to_list Ordnode.foldr_cons_eq_toList
@[simp]
theorem toList_nil : toList (@nil α) = [] :=
rfl
#align ordnode.to_list_nil Ordnode.toList_nil
@[simp]
theorem toList_node (s l x r) : toList (@node α s l x r) = toList l ++ x :: toList r := by
rw [toList, foldr, foldr_cons_eq_toList]; rfl
#align ordnode.to_list_node Ordnode.toList_node
theorem emem_iff_mem_toList {x : α} {t} : Emem x t ↔ x ∈ toList t := by
unfold Emem; induction t <;> simp [Any, *, or_assoc]
#align ordnode.emem_iff_mem_to_list Ordnode.emem_iff_mem_toList
theorem length_toList' : ∀ t : Ordnode α, (toList t).length = t.realSize
| nil => rfl
| node _ l _ r => by
rw [toList_node, List.length_append, List.length_cons, length_toList' l,
length_toList' r]; rfl
#align ordnode.length_to_list' Ordnode.length_toList'
theorem length_toList {t : Ordnode α} (h : Sized t) : (toList t).length = t.size := by
rw [length_toList', size_eq_realSize h]
#align ordnode.length_to_list Ordnode.length_toList
theorem equiv_iff {t₁ t₂ : Ordnode α} (h₁ : Sized t₁) (h₂ : Sized t₂) :
Equiv t₁ t₂ ↔ toList t₁ = toList t₂ :=
and_iff_right_of_imp fun h => by rw [← length_toList h₁, h, length_toList h₂]
#align ordnode.equiv_iff Ordnode.equiv_iff
theorem pos_size_of_mem [LE α] [@DecidableRel α (· ≤ ·)] {x : α} {t : Ordnode α} (h : Sized t)
(h_mem : x ∈ t) : 0 < size t := by cases t; · { contradiction }; · { simp [h.1] }
#align ordnode.pos_size_of_mem Ordnode.pos_size_of_mem
theorem findMin'_dual : ∀ (t) (x : α), findMin' (dual t) x = findMax' x t
| nil, _ => rfl
| node _ _ x r, _ => findMin'_dual r x
#align ordnode.find_min'_dual Ordnode.findMin'_dual
theorem findMax'_dual (t) (x : α) : findMax' x (dual t) = findMin' t x := by
rw [← findMin'_dual, dual_dual]
#align ordnode.find_max'_dual Ordnode.findMax'_dual
theorem findMin_dual : ∀ t : Ordnode α, findMin (dual t) = findMax t
| nil => rfl
| node _ _ _ _ => congr_arg some <| findMin'_dual _ _
#align ordnode.find_min_dual Ordnode.findMin_dual
theorem findMax_dual (t : Ordnode α) : findMax (dual t) = findMin t := by
rw [← findMin_dual, dual_dual]
#align ordnode.find_max_dual Ordnode.findMax_dual
theorem dual_eraseMin : ∀ t : Ordnode α, dual (eraseMin t) = eraseMax (dual t)
| nil => rfl
| node _ nil x r => rfl
| node _ (node sz l' y r') x r => by
rw [eraseMin, dual_balanceR, dual_eraseMin (node sz l' y r'), dual, dual, dual, eraseMax]
#align ordnode.dual_erase_min Ordnode.dual_eraseMin
theorem dual_eraseMax (t : Ordnode α) : dual (eraseMax t) = eraseMin (dual t) := by
rw [← dual_dual (eraseMin _), dual_eraseMin, dual_dual]
#align ordnode.dual_erase_max Ordnode.dual_eraseMax
theorem splitMin_eq :
∀ (s l) (x : α) (r), splitMin' l x r = (findMin' l x, eraseMin (node s l x r))
| _, nil, x, r => rfl
| _, node ls ll lx lr, x, r => by rw [splitMin', splitMin_eq ls ll lx lr, findMin', eraseMin]
#align ordnode.split_min_eq Ordnode.splitMin_eq
theorem splitMax_eq :
∀ (s l) (x : α) (r), splitMax' l x r = (eraseMax (node s l x r), findMax' x r)
| _, l, x, nil => rfl
| _, l, x, node ls ll lx lr => by rw [splitMax', splitMax_eq ls ll lx lr, findMax', eraseMax]
#align ordnode.split_max_eq Ordnode.splitMax_eq
-- @[elab_as_elim] -- Porting note: unexpected eliminator resulting type
theorem findMin'_all {P : α → Prop} : ∀ (t) (x : α), All P t → P x → P (findMin' t x)
| nil, _x, _, hx => hx
| node _ ll lx _, _, ⟨h₁, h₂, _⟩, _ => findMin'_all ll lx h₁ h₂
#align ordnode.find_min'_all Ordnode.findMin'_all
-- @[elab_as_elim] -- Porting note: unexpected eliminator resulting type
theorem findMax'_all {P : α → Prop} : ∀ (x : α) (t), P x → All P t → P (findMax' x t)
| _x, nil, hx, _ => hx
| _, node _ _ lx lr, _, ⟨_, h₂, h₃⟩ => findMax'_all lx lr h₂ h₃
#align ordnode.find_max'_all Ordnode.findMax'_all
@[simp]
theorem merge_nil_left (t : Ordnode α) : merge t nil = t := by cases t <;> rfl
#align ordnode.merge_nil_left Ordnode.merge_nil_left
@[simp]
theorem merge_nil_right (t : Ordnode α) : merge nil t = t :=
rfl
#align ordnode.merge_nil_right Ordnode.merge_nil_right
@[simp]
theorem merge_node {ls ll lx lr rs rl rx rr} :
merge (@node α ls ll lx lr) (node rs rl rx rr) =
if delta * ls < rs then balanceL (merge (node ls ll lx lr) rl) rx rr
else if delta * rs < ls then balanceR ll lx (merge lr (node rs rl rx rr))
else glue (node ls ll lx lr) (node rs rl rx rr) :=
rfl
#align ordnode.merge_node Ordnode.merge_node
theorem dual_insert [Preorder α] [IsTotal α (· ≤ ·)] [@DecidableRel α (· ≤ ·)] (x : α) :
∀ t : Ordnode α, dual (Ordnode.insert x t) = @Ordnode.insert αᵒᵈ _ _ x (dual t)
| nil => rfl
| node _ l y r => by
have : @cmpLE αᵒᵈ _ _ x y = cmpLE y x := rfl
rw [Ordnode.insert, dual, Ordnode.insert, this, ← cmpLE_swap x y]
cases cmpLE x y <;>
simp [Ordering.swap, Ordnode.insert, dual_balanceL, dual_balanceR, dual_insert]
#align ordnode.dual_insert Ordnode.dual_insert
theorem balance_eq_balance' {l x r} (hl : Balanced l) (hr : Balanced r) (sl : Sized l)
(sr : Sized r) : @balance α l x r = balance' l x r := by
cases' l with ls ll lx lr
· cases' r with rs rl rx rr
· rfl
· rw [sr.eq_node'] at hr ⊢
cases' rl with rls rll rlx rlr <;> cases' rr with rrs rrl rrx rrr <;>
dsimp [balance, balance']
· rfl
· have : size rrl = 0 ∧ size rrr = 0 := by
have := balancedSz_zero.1 hr.1.symm
rwa [size, sr.2.2.1, Nat.succ_le_succ_iff, Nat.le_zero, add_eq_zero_iff] at this
cases sr.2.2.2.1.size_eq_zero.1 this.1
cases sr.2.2.2.2.size_eq_zero.1 this.2
obtain rfl : rrs = 1 := sr.2.2.1
rw [if_neg, if_pos, rotateL_node, if_pos]; · rfl
all_goals dsimp only [size]; decide
· have : size rll = 0 ∧ size rlr = 0 := by
have := balancedSz_zero.1 hr.1
rwa [size, sr.2.1.1, Nat.succ_le_succ_iff, Nat.le_zero, add_eq_zero_iff] at this
cases sr.2.1.2.1.size_eq_zero.1 this.1
cases sr.2.1.2.2.size_eq_zero.1 this.2
obtain rfl : rls = 1 := sr.2.1.1
rw [if_neg, if_pos, rotateL_node, if_neg]; · rfl
all_goals dsimp only [size]; decide
· symm; rw [zero_add, if_neg, if_pos, rotateL]
· dsimp only [size_node]; split_ifs
· simp [node3L, node']; abel
· simp [node4L, node', sr.2.1.1]; abel
· apply Nat.zero_lt_succ
· exact not_le_of_gt (Nat.succ_lt_succ (add_pos sr.2.1.pos sr.2.2.pos))
· cases' r with rs rl rx rr
· rw [sl.eq_node'] at hl ⊢
cases' ll with lls lll llx llr <;> cases' lr with lrs lrl lrx lrr <;>
dsimp [balance, balance']
· rfl
· have : size lrl = 0 ∧ size lrr = 0 := by
have := balancedSz_zero.1 hl.1.symm
rwa [size, sl.2.2.1, Nat.succ_le_succ_iff, Nat.le_zero, add_eq_zero_iff] at this
cases sl.2.2.2.1.size_eq_zero.1 this.1
cases sl.2.2.2.2.size_eq_zero.1 this.2
obtain rfl : lrs = 1 := sl.2.2.1
rw [if_neg, if_neg, if_pos, rotateR_node, if_neg]; · rfl
all_goals dsimp only [size]; decide
· have : size lll = 0 ∧ size llr = 0 := by
have := balancedSz_zero.1 hl.1
rwa [size, sl.2.1.1, Nat.succ_le_succ_iff, Nat.le_zero, add_eq_zero_iff] at this
cases sl.2.1.2.1.size_eq_zero.1 this.1
cases sl.2.1.2.2.size_eq_zero.1 this.2
obtain rfl : lls = 1 := sl.2.1.1
rw [if_neg, if_neg, if_pos, rotateR_node, if_pos]; · rfl
all_goals dsimp only [size]; decide
· symm; rw [if_neg, if_neg, if_pos, rotateR]
· dsimp only [size_node]; split_ifs
· simp [node3R, node']; abel
· simp [node4R, node', sl.2.2.1]; abel
· apply Nat.zero_lt_succ
· apply Nat.not_lt_zero
· exact not_le_of_gt (Nat.succ_lt_succ (add_pos sl.2.1.pos sl.2.2.pos))
· simp [balance, balance']
symm; rw [if_neg]
· split_ifs with h h_1
· have rd : delta ≤ size rl + size rr := by
have := lt_of_le_of_lt (Nat.mul_le_mul_left _ sl.pos) h
rwa [sr.1, Nat.lt_succ_iff] at this
cases' rl with rls rll rlx rlr
· rw [size, zero_add] at rd
exact absurd (le_trans rd (balancedSz_zero.1 hr.1.symm)) (by decide)
cases' rr with rrs rrl rrx rrr
· exact absurd (le_trans rd (balancedSz_zero.1 hr.1)) (by decide)
dsimp [rotateL]; split_ifs
· simp [node3L, node', sr.1]; abel
· simp [node4L, node', sr.1, sr.2.1.1]; abel
· have ld : delta ≤ size ll + size lr := by
have := lt_of_le_of_lt (Nat.mul_le_mul_left _ sr.pos) h_1
rwa [sl.1, Nat.lt_succ_iff] at this
cases' ll with lls lll llx llr
· rw [size, zero_add] at ld
exact absurd (le_trans ld (balancedSz_zero.1 hl.1.symm)) (by decide)
cases' lr with lrs lrl lrx lrr
· exact absurd (le_trans ld (balancedSz_zero.1 hl.1)) (by decide)
dsimp [rotateR]; split_ifs
· simp [node3R, node', sl.1]; abel
· simp [node4R, node', sl.1, sl.2.2.1]; abel
· simp [node']
· exact not_le_of_gt (add_le_add (Nat.succ_le_of_lt sl.pos) (Nat.succ_le_of_lt sr.pos))
#align ordnode.balance_eq_balance' Ordnode.balance_eq_balance'
theorem balanceL_eq_balance {l x r} (sl : Sized l) (sr : Sized r) (H1 : size l = 0 → size r ≤ 1)
(H2 : 1 ≤ size l → 1 ≤ size r → size r ≤ delta * size l) :
@balanceL α l x r = balance l x r := by
cases' r with rs rl rx rr
· rfl
· cases' l with ls ll lx lr
· have : size rl = 0 ∧ size rr = 0 := by
have := H1 rfl
rwa [size, sr.1, Nat.succ_le_succ_iff, Nat.le_zero, add_eq_zero_iff] at this
cases sr.2.1.size_eq_zero.1 this.1
cases sr.2.2.size_eq_zero.1 this.2
rw [sr.eq_node']; rfl
· replace H2 : ¬rs > delta * ls := not_lt_of_le (H2 sl.pos sr.pos)
simp [balanceL, balance, H2]; split_ifs <;> simp [add_comm]
#align ordnode.balance_l_eq_balance Ordnode.balanceL_eq_balance
def Raised (n m : ℕ) : Prop :=
m = n ∨ m = n + 1
#align ordnode.raised Ordnode.Raised
theorem raised_iff {n m} : Raised n m ↔ n ≤ m ∧ m ≤ n + 1 := by
constructor
· rintro (rfl | rfl)
· exact ⟨le_rfl, Nat.le_succ _⟩
· exact ⟨Nat.le_succ _, le_rfl⟩
· rintro ⟨h₁, h₂⟩
rcases eq_or_lt_of_le h₁ with (rfl | h₁)
· exact Or.inl rfl
· exact Or.inr (le_antisymm h₂ h₁)
#align ordnode.raised_iff Ordnode.raised_iff
theorem Raised.dist_le {n m} (H : Raised n m) : Nat.dist n m ≤ 1 := by
cases' raised_iff.1 H with H1 H2; rwa [Nat.dist_eq_sub_of_le H1, tsub_le_iff_left]
#align ordnode.raised.dist_le Ordnode.Raised.dist_le
theorem Raised.dist_le' {n m} (H : Raised n m) : Nat.dist m n ≤ 1 := by
rw [Nat.dist_comm]; exact H.dist_le
#align ordnode.raised.dist_le' Ordnode.Raised.dist_le'
theorem Raised.add_left (k) {n m} (H : Raised n m) : Raised (k + n) (k + m) := by
rcases H with (rfl | rfl)
· exact Or.inl rfl
· exact Or.inr rfl
#align ordnode.raised.add_left Ordnode.Raised.add_left
theorem Raised.add_right (k) {n m} (H : Raised n m) : Raised (n + k) (m + k) := by
rw [add_comm, add_comm m]; exact H.add_left _
#align ordnode.raised.add_right Ordnode.Raised.add_right
theorem Raised.right {l x₁ x₂ r₁ r₂} (H : Raised (size r₁) (size r₂)) :
Raised (size (@node' α l x₁ r₁)) (size (@node' α l x₂ r₂)) := by
rw [node', size_node, size_node]; generalize size r₂ = m at H ⊢
rcases H with (rfl | rfl)
· exact Or.inl rfl
· exact Or.inr rfl
#align ordnode.raised.right Ordnode.Raised.right
theorem balanceL_eq_balance' {l x r} (hl : Balanced l) (hr : Balanced r) (sl : Sized l)
(sr : Sized r)
(H :
(∃ l', Raised l' (size l) ∧ BalancedSz l' (size r)) ∨
∃ r', Raised (size r) r' ∧ BalancedSz (size l) r') :
@balanceL α l x r = balance' l x r := by
rw [← balance_eq_balance' hl hr sl sr, balanceL_eq_balance sl sr]
· intro l0; rw [l0] at H
rcases H with (⟨_, ⟨⟨⟩⟩ | ⟨⟨⟩⟩, H⟩ | ⟨r', e, H⟩)
· exact balancedSz_zero.1 H.symm
exact le_trans (raised_iff.1 e).1 (balancedSz_zero.1 H.symm)
· intro l1 _
rcases H with (⟨l', e, H | ⟨_, H₂⟩⟩ | ⟨r', e, H | ⟨_, H₂⟩⟩)
· exact le_trans (le_trans (Nat.le_add_left _ _) H) (mul_pos (by decide) l1 : (0 : ℕ) < _)
· exact le_trans H₂ (Nat.mul_le_mul_left _ (raised_iff.1 e).1)
· cases raised_iff.1 e; unfold delta; omega
· exact le_trans (raised_iff.1 e).1 H₂
#align ordnode.balance_l_eq_balance' Ordnode.balanceL_eq_balance'
theorem balance_sz_dual {l r}
(H : (∃ l', Raised (@size α l) l' ∧ BalancedSz l' (@size α r)) ∨
∃ r', Raised r' (size r) ∧ BalancedSz (size l) r') :
(∃ l', Raised l' (size (dual r)) ∧ BalancedSz l' (size (dual l))) ∨
∃ r', Raised (size (dual l)) r' ∧ BalancedSz (size (dual r)) r' := by
rw [size_dual, size_dual]
exact
H.symm.imp (Exists.imp fun _ => And.imp_right BalancedSz.symm)
(Exists.imp fun _ => And.imp_right BalancedSz.symm)
#align ordnode.balance_sz_dual Ordnode.balance_sz_dual
theorem size_balanceL {l x r} (hl : Balanced l) (hr : Balanced r) (sl : Sized l) (sr : Sized r)
(H : (∃ l', Raised l' (size l) ∧ BalancedSz l' (size r)) ∨
∃ r', Raised (size r) r' ∧ BalancedSz (size l) r') :
size (@balanceL α l x r) = size l + size r + 1 := by
rw [balanceL_eq_balance' hl hr sl sr H, size_balance' sl sr]
#align ordnode.size_balance_l Ordnode.size_balanceL
theorem all_balanceL {P l x r} (hl : Balanced l) (hr : Balanced r) (sl : Sized l) (sr : Sized r)
(H :
(∃ l', Raised l' (size l) ∧ BalancedSz l' (size r)) ∨
∃ r', Raised (size r) r' ∧ BalancedSz (size l) r') :
All P (@balanceL α l x r) ↔ All P l ∧ P x ∧ All P r := by
rw [balanceL_eq_balance' hl hr sl sr H, all_balance']
#align ordnode.all_balance_l Ordnode.all_balanceL
theorem balanceR_eq_balance' {l x r} (hl : Balanced l) (hr : Balanced r) (sl : Sized l)
(sr : Sized r)
(H : (∃ l', Raised (size l) l' ∧ BalancedSz l' (size r)) ∨
∃ r', Raised r' (size r) ∧ BalancedSz (size l) r') :
@balanceR α l x r = balance' l x r := by
rw [← dual_dual (balanceR l x r), dual_balanceR,
balanceL_eq_balance' hr.dual hl.dual sr.dual sl.dual (balance_sz_dual H), ← dual_balance',
dual_dual]
#align ordnode.balance_r_eq_balance' Ordnode.balanceR_eq_balance'
theorem size_balanceR {l x r} (hl : Balanced l) (hr : Balanced r) (sl : Sized l) (sr : Sized r)
(H : (∃ l', Raised (size l) l' ∧ BalancedSz l' (size r)) ∨
∃ r', Raised r' (size r) ∧ BalancedSz (size l) r') :
size (@balanceR α l x r) = size l + size r + 1 := by
rw [balanceR_eq_balance' hl hr sl sr H, size_balance' sl sr]
#align ordnode.size_balance_r Ordnode.size_balanceR
theorem all_balanceR {P l x r} (hl : Balanced l) (hr : Balanced r) (sl : Sized l) (sr : Sized r)
(H :
(∃ l', Raised (size l) l' ∧ BalancedSz l' (size r)) ∨
∃ r', Raised r' (size r) ∧ BalancedSz (size l) r') :
All P (@balanceR α l x r) ↔ All P l ∧ P x ∧ All P r := by
rw [balanceR_eq_balance' hl hr sl sr H, all_balance']
#align ordnode.all_balance_r Ordnode.all_balanceR
section
variable [Preorder α]
def Bounded : Ordnode α → WithBot α → WithTop α → Prop
| nil, some a, some b => a < b
| nil, _, _ => True
| node _ l x r, o₁, o₂ => Bounded l o₁ x ∧ Bounded r (↑x) o₂
#align ordnode.bounded Ordnode.Bounded
theorem Bounded.dual :
∀ {t : Ordnode α} {o₁ o₂}, Bounded t o₁ o₂ → @Bounded αᵒᵈ _ (dual t) o₂ o₁
| nil, o₁, o₂, h => by cases o₁ <;> cases o₂ <;> trivial
| node _ l x r, _, _, ⟨ol, Or⟩ => ⟨Or.dual, ol.dual⟩
#align ordnode.bounded.dual Ordnode.Bounded.dual
theorem Bounded.dual_iff {t : Ordnode α} {o₁ o₂} :
Bounded t o₁ o₂ ↔ @Bounded αᵒᵈ _ (.dual t) o₂ o₁ :=
⟨Bounded.dual, fun h => by
have := Bounded.dual h; rwa [dual_dual, OrderDual.Preorder.dual_dual] at this⟩
#align ordnode.bounded.dual_iff Ordnode.Bounded.dual_iff
theorem Bounded.weak_left : ∀ {t : Ordnode α} {o₁ o₂}, Bounded t o₁ o₂ → Bounded t ⊥ o₂
| nil, o₁, o₂, h => by cases o₂ <;> trivial
| node _ l x r, _, _, ⟨ol, Or⟩ => ⟨ol.weak_left, Or⟩
#align ordnode.bounded.weak_left Ordnode.Bounded.weak_left
theorem Bounded.weak_right : ∀ {t : Ordnode α} {o₁ o₂}, Bounded t o₁ o₂ → Bounded t o₁ ⊤
| nil, o₁, o₂, h => by cases o₁ <;> trivial
| node _ l x r, _, _, ⟨ol, Or⟩ => ⟨ol, Or.weak_right⟩
#align ordnode.bounded.weak_right Ordnode.Bounded.weak_right
theorem Bounded.weak {t : Ordnode α} {o₁ o₂} (h : Bounded t o₁ o₂) : Bounded t ⊥ ⊤ :=
h.weak_left.weak_right
#align ordnode.bounded.weak Ordnode.Bounded.weak
theorem Bounded.mono_left {x y : α} (xy : x ≤ y) :
∀ {t : Ordnode α} {o}, Bounded t y o → Bounded t x o
| nil, none, _ => ⟨⟩
| nil, some _, h => lt_of_le_of_lt xy h
| node _ _ _ _, _o, ⟨ol, or⟩ => ⟨ol.mono_left xy, or⟩
#align ordnode.bounded.mono_left Ordnode.Bounded.mono_left
theorem Bounded.mono_right {x y : α} (xy : x ≤ y) :
∀ {t : Ordnode α} {o}, Bounded t o x → Bounded t o y
| nil, none, _ => ⟨⟩
| nil, some _, h => lt_of_lt_of_le h xy
| node _ _ _ _, _o, ⟨ol, or⟩ => ⟨ol, or.mono_right xy⟩
#align ordnode.bounded.mono_right Ordnode.Bounded.mono_right
theorem Bounded.to_lt : ∀ {t : Ordnode α} {x y : α}, Bounded t x y → x < y
| nil, _, _, h => h
| node _ _ _ _, _, _, ⟨h₁, h₂⟩ => lt_trans h₁.to_lt h₂.to_lt
#align ordnode.bounded.to_lt Ordnode.Bounded.to_lt
theorem Bounded.to_nil {t : Ordnode α} : ∀ {o₁ o₂}, Bounded t o₁ o₂ → Bounded nil o₁ o₂
| none, _, _ => ⟨⟩
| some _, none, _ => ⟨⟩
| some _, some _, h => h.to_lt
#align ordnode.bounded.to_nil Ordnode.Bounded.to_nil
theorem Bounded.trans_left {t₁ t₂ : Ordnode α} {x : α} :
∀ {o₁ o₂}, Bounded t₁ o₁ x → Bounded t₂ x o₂ → Bounded t₂ o₁ o₂
| none, _, _, h₂ => h₂.weak_left
| some _, _, h₁, h₂ => h₂.mono_left (le_of_lt h₁.to_lt)
#align ordnode.bounded.trans_left Ordnode.Bounded.trans_left
theorem Bounded.trans_right {t₁ t₂ : Ordnode α} {x : α} :
∀ {o₁ o₂}, Bounded t₁ o₁ x → Bounded t₂ x o₂ → Bounded t₁ o₁ o₂
| _, none, h₁, _ => h₁.weak_right
| _, some _, h₁, h₂ => h₁.mono_right (le_of_lt h₂.to_lt)
#align ordnode.bounded.trans_right Ordnode.Bounded.trans_right
theorem Bounded.mem_lt : ∀ {t o} {x : α}, Bounded t o x → All (· < x) t
| nil, _, _, _ => ⟨⟩
| node _ _ _ _, _, _, ⟨h₁, h₂⟩ =>
⟨h₁.mem_lt.imp fun _ h => lt_trans h h₂.to_lt, h₂.to_lt, h₂.mem_lt⟩
#align ordnode.bounded.mem_lt Ordnode.Bounded.mem_lt
theorem Bounded.mem_gt : ∀ {t o} {x : α}, Bounded t x o → All (· > x) t
| nil, _, _, _ => ⟨⟩
| node _ _ _ _, _, _, ⟨h₁, h₂⟩ => ⟨h₁.mem_gt, h₁.to_lt, h₂.mem_gt.imp fun _ => lt_trans h₁.to_lt⟩
#align ordnode.bounded.mem_gt Ordnode.Bounded.mem_gt
theorem Bounded.of_lt :
∀ {t o₁ o₂} {x : α}, Bounded t o₁ o₂ → Bounded nil o₁ x → All (· < x) t → Bounded t o₁ x
| nil, _, _, _, _, hn, _ => hn
| node _ _ _ _, _, _, _, ⟨h₁, h₂⟩, _, ⟨_, al₂, al₃⟩ => ⟨h₁, h₂.of_lt al₂ al₃⟩
#align ordnode.bounded.of_lt Ordnode.Bounded.of_lt
theorem Bounded.of_gt :
∀ {t o₁ o₂} {x : α}, Bounded t o₁ o₂ → Bounded nil x o₂ → All (· > x) t → Bounded t x o₂
| nil, _, _, _, _, hn, _ => hn
| node _ _ _ _, _, _, _, ⟨h₁, h₂⟩, _, ⟨al₁, al₂, _⟩ => ⟨h₁.of_gt al₂ al₁, h₂⟩
#align ordnode.bounded.of_gt Ordnode.Bounded.of_gt
theorem Bounded.to_sep {t₁ t₂ o₁ o₂} {x : α}
(h₁ : Bounded t₁ o₁ (x : WithTop α)) (h₂ : Bounded t₂ (x : WithBot α) o₂) :
t₁.All fun y => t₂.All fun z : α => y < z := by
refine h₁.mem_lt.imp fun y yx => ?_
exact h₂.mem_gt.imp fun z xz => lt_trans yx xz
#align ordnode.bounded.to_sep Ordnode.Bounded.to_sep
end
section
variable [Preorder α]
structure Valid' (lo : WithBot α) (t : Ordnode α) (hi : WithTop α) : Prop where
ord : t.Bounded lo hi
sz : t.Sized
bal : t.Balanced
#align ordnode.valid' Ordnode.Valid'
#align ordnode.valid'.ord Ordnode.Valid'.ord
#align ordnode.valid'.sz Ordnode.Valid'.sz
#align ordnode.valid'.bal Ordnode.Valid'.bal
def Valid (t : Ordnode α) : Prop :=
Valid' ⊥ t ⊤
#align ordnode.valid Ordnode.Valid
theorem Valid'.mono_left {x y : α} (xy : x ≤ y) {t : Ordnode α} {o} (h : Valid' y t o) :
Valid' x t o :=
⟨h.1.mono_left xy, h.2, h.3⟩
#align ordnode.valid'.mono_left Ordnode.Valid'.mono_left
theorem Valid'.mono_right {x y : α} (xy : x ≤ y) {t : Ordnode α} {o} (h : Valid' o t x) :
Valid' o t y :=
⟨h.1.mono_right xy, h.2, h.3⟩
#align ordnode.valid'.mono_right Ordnode.Valid'.mono_right
theorem Valid'.trans_left {t₁ t₂ : Ordnode α} {x : α} {o₁ o₂} (h : Bounded t₁ o₁ x)
(H : Valid' x t₂ o₂) : Valid' o₁ t₂ o₂ :=
⟨h.trans_left H.1, H.2, H.3⟩
#align ordnode.valid'.trans_left Ordnode.Valid'.trans_left
theorem Valid'.trans_right {t₁ t₂ : Ordnode α} {x : α} {o₁ o₂} (H : Valid' o₁ t₁ x)
(h : Bounded t₂ x o₂) : Valid' o₁ t₁ o₂ :=
⟨H.1.trans_right h, H.2, H.3⟩
#align ordnode.valid'.trans_right Ordnode.Valid'.trans_right
theorem Valid'.of_lt {t : Ordnode α} {x : α} {o₁ o₂} (H : Valid' o₁ t o₂) (h₁ : Bounded nil o₁ x)
(h₂ : All (· < x) t) : Valid' o₁ t x :=
⟨H.1.of_lt h₁ h₂, H.2, H.3⟩
#align ordnode.valid'.of_lt Ordnode.Valid'.of_lt
theorem Valid'.of_gt {t : Ordnode α} {x : α} {o₁ o₂} (H : Valid' o₁ t o₂) (h₁ : Bounded nil x o₂)
(h₂ : All (· > x) t) : Valid' x t o₂ :=
⟨H.1.of_gt h₁ h₂, H.2, H.3⟩
#align ordnode.valid'.of_gt Ordnode.Valid'.of_gt
theorem Valid'.valid {t o₁ o₂} (h : @Valid' α _ o₁ t o₂) : Valid t :=
⟨h.1.weak, h.2, h.3⟩
#align ordnode.valid'.valid Ordnode.Valid'.valid
theorem valid'_nil {o₁ o₂} (h : Bounded nil o₁ o₂) : Valid' o₁ (@nil α) o₂ :=
⟨h, ⟨⟩, ⟨⟩⟩
#align ordnode.valid'_nil Ordnode.valid'_nil
theorem valid_nil : Valid (@nil α) :=
valid'_nil ⟨⟩
#align ordnode.valid_nil Ordnode.valid_nil
theorem Valid'.node {s l} {x : α} {r o₁ o₂} (hl : Valid' o₁ l x) (hr : Valid' x r o₂)
(H : BalancedSz (size l) (size r)) (hs : s = size l + size r + 1) :
Valid' o₁ (@node α s l x r) o₂ :=
⟨⟨hl.1, hr.1⟩, ⟨hs, hl.2, hr.2⟩, ⟨H, hl.3, hr.3⟩⟩
#align ordnode.valid'.node Ordnode.Valid'.node
theorem Valid'.dual : ∀ {t : Ordnode α} {o₁ o₂}, Valid' o₁ t o₂ → @Valid' αᵒᵈ _ o₂ (dual t) o₁
| .nil, o₁, o₂, h => valid'_nil h.1.dual
| .node _ l x r, o₁, o₂, ⟨⟨ol, Or⟩, ⟨rfl, sl, sr⟩, ⟨b, bl, br⟩⟩ =>
let ⟨ol', sl', bl'⟩ := Valid'.dual ⟨ol, sl, bl⟩
let ⟨or', sr', br'⟩ := Valid'.dual ⟨Or, sr, br⟩
⟨⟨or', ol'⟩, ⟨by simp [size_dual, add_comm], sr', sl'⟩,
⟨by rw [size_dual, size_dual]; exact b.symm, br', bl'⟩⟩
#align ordnode.valid'.dual Ordnode.Valid'.dual
theorem Valid'.dual_iff {t : Ordnode α} {o₁ o₂} : Valid' o₁ t o₂ ↔ @Valid' αᵒᵈ _ o₂ (.dual t) o₁ :=
⟨Valid'.dual, fun h => by
have := Valid'.dual h; rwa [dual_dual, OrderDual.Preorder.dual_dual] at this⟩
#align ordnode.valid'.dual_iff Ordnode.Valid'.dual_iff
theorem Valid.dual {t : Ordnode α} : Valid t → @Valid αᵒᵈ _ (.dual t) :=
Valid'.dual
#align ordnode.valid.dual Ordnode.Valid.dual
theorem Valid.dual_iff {t : Ordnode α} : Valid t ↔ @Valid αᵒᵈ _ (.dual t) :=
Valid'.dual_iff
#align ordnode.valid.dual_iff Ordnode.Valid.dual_iff
theorem Valid'.left {s l x r o₁ o₂} (H : Valid' o₁ (@Ordnode.node α s l x r) o₂) : Valid' o₁ l x :=
⟨H.1.1, H.2.2.1, H.3.2.1⟩
#align ordnode.valid'.left Ordnode.Valid'.left
theorem Valid'.right {s l x r o₁ o₂} (H : Valid' o₁ (@Ordnode.node α s l x r) o₂) : Valid' x r o₂ :=
⟨H.1.2, H.2.2.2, H.3.2.2⟩
#align ordnode.valid'.right Ordnode.Valid'.right
nonrec theorem Valid.left {s l x r} (H : Valid (@node α s l x r)) : Valid l :=
H.left.valid
#align ordnode.valid.left Ordnode.Valid.left
nonrec theorem Valid.right {s l x r} (H : Valid (@node α s l x r)) : Valid r :=
H.right.valid
#align ordnode.valid.right Ordnode.Valid.right
theorem Valid.size_eq {s l x r} (H : Valid (@node α s l x r)) :
size (@node α s l x r) = size l + size r + 1 :=
H.2.1
#align ordnode.valid.size_eq Ordnode.Valid.size_eq
theorem Valid'.node' {l} {x : α} {r o₁ o₂} (hl : Valid' o₁ l x) (hr : Valid' x r o₂)
(H : BalancedSz (size l) (size r)) : Valid' o₁ (@node' α l x r) o₂ :=
hl.node hr H rfl
#align ordnode.valid'.node' Ordnode.Valid'.node'
theorem valid'_singleton {x : α} {o₁ o₂} (h₁ : Bounded nil o₁ x) (h₂ : Bounded nil x o₂) :
Valid' o₁ (singleton x : Ordnode α) o₂ :=
(valid'_nil h₁).node (valid'_nil h₂) (Or.inl zero_le_one) rfl
#align ordnode.valid'_singleton Ordnode.valid'_singleton
theorem valid_singleton {x : α} : Valid (singleton x : Ordnode α) :=
valid'_singleton ⟨⟩ ⟨⟩
#align ordnode.valid_singleton Ordnode.valid_singleton
theorem Valid'.node3L {l} {x : α} {m} {y : α} {r o₁ o₂} (hl : Valid' o₁ l x) (hm : Valid' x m y)
(hr : Valid' y r o₂) (H1 : BalancedSz (size l) (size m))
(H2 : BalancedSz (size l + size m + 1) (size r)) : Valid' o₁ (@node3L α l x m y r) o₂ :=
(hl.node' hm H1).node' hr H2
#align ordnode.valid'.node3_l Ordnode.Valid'.node3L
theorem Valid'.node3R {l} {x : α} {m} {y : α} {r o₁ o₂} (hl : Valid' o₁ l x) (hm : Valid' x m y)
(hr : Valid' y r o₂) (H1 : BalancedSz (size l) (size m + size r + 1))
(H2 : BalancedSz (size m) (size r)) : Valid' o₁ (@node3R α l x m y r) o₂ :=
hl.node' (hm.node' hr H2) H1
#align ordnode.valid'.node3_r Ordnode.Valid'.node3R
theorem Valid'.node4L_lemma₁ {a b c d : ℕ} (lr₂ : 3 * (b + c + 1 + d) ≤ 16 * a + 9)
(mr₂ : b + c + 1 ≤ 3 * d) (mm₁ : b ≤ 3 * c) : b < 3 * a + 1 := by omega
#align ordnode.valid'.node4_l_lemma₁ Ordnode.Valid'.node4L_lemma₁
theorem Valid'.node4L_lemma₂ {b c d : ℕ} (mr₂ : b + c + 1 ≤ 3 * d) : c ≤ 3 * d := by omega
#align ordnode.valid'.node4_l_lemma₂ Ordnode.Valid'.node4L_lemma₂
theorem Valid'.node4L_lemma₃ {b c d : ℕ} (mr₁ : 2 * d ≤ b + c + 1) (mm₁ : b ≤ 3 * c) :
d ≤ 3 * c := by omega
#align ordnode.valid'.node4_l_lemma₃ Ordnode.Valid'.node4L_lemma₃
theorem Valid'.node4L_lemma₄ {a b c d : ℕ} (lr₁ : 3 * a ≤ b + c + 1 + d) (mr₂ : b + c + 1 ≤ 3 * d)
(mm₁ : b ≤ 3 * c) : a + b + 1 ≤ 3 * (c + d + 1) := by omega
#align ordnode.valid'.node4_l_lemma₄ Ordnode.Valid'.node4L_lemma₄
theorem Valid'.node4L_lemma₅ {a b c d : ℕ} (lr₂ : 3 * (b + c + 1 + d) ≤ 16 * a + 9)
(mr₁ : 2 * d ≤ b + c + 1) (mm₂ : c ≤ 3 * b) : c + d + 1 ≤ 3 * (a + b + 1) := by omega
#align ordnode.valid'.node4_l_lemma₅ Ordnode.Valid'.node4L_lemma₅
theorem Valid'.node4L {l} {x : α} {m} {y : α} {r o₁ o₂} (hl : Valid' o₁ l x) (hm : Valid' x m y)
(hr : Valid' (↑y) r o₂) (Hm : 0 < size m)
(H : size l = 0 ∧ size m = 1 ∧ size r ≤ 1 ∨
0 < size l ∧
ratio * size r ≤ size m ∧
delta * size l ≤ size m + size r ∧
3 * (size m + size r) ≤ 16 * size l + 9 ∧ size m ≤ delta * size r) :
Valid' o₁ (@node4L α l x m y r) o₂ := by
cases' m with s ml z mr; · cases Hm
suffices
BalancedSz (size l) (size ml) ∧
BalancedSz (size mr) (size r) ∧ BalancedSz (size l + size ml + 1) (size mr + size r + 1) from
Valid'.node' (hl.node' hm.left this.1) (hm.right.node' hr this.2.1) this.2.2
rcases H with (⟨l0, m1, r0⟩ | ⟨l0, mr₁, lr₁, lr₂, mr₂⟩)
· rw [hm.2.size_eq, Nat.succ_inj', add_eq_zero_iff] at m1
rw [l0, m1.1, m1.2]; revert r0; rcases size r with (_ | _ | _) <;>
[decide; decide; (intro r0; unfold BalancedSz delta; omega)]
· rcases Nat.eq_zero_or_pos (size r) with r0 | r0
· rw [r0] at mr₂; cases not_le_of_lt Hm mr₂
rw [hm.2.size_eq] at lr₁ lr₂ mr₁ mr₂
by_cases mm : size ml + size mr ≤ 1
· have r1 :=
le_antisymm
((mul_le_mul_left (by decide)).1 (le_trans mr₁ (Nat.succ_le_succ mm) : _ ≤ ratio * 1)) r0
rw [r1, add_assoc] at lr₁
have l1 :=
le_antisymm
((mul_le_mul_left (by decide)).1 (le_trans lr₁ (add_le_add_right mm 2) : _ ≤ delta * 1))
l0
rw [l1, r1]
revert mm; cases size ml <;> cases size mr <;> intro mm
· decide
· rw [zero_add] at mm; rcases mm with (_ | ⟨⟨⟩⟩)
decide
· rcases mm with (_ | ⟨⟨⟩⟩); decide
· rw [Nat.succ_add] at mm; rcases mm with (_ | ⟨⟨⟩⟩)
rcases hm.3.1.resolve_left mm with ⟨mm₁, mm₂⟩
rcases Nat.eq_zero_or_pos (size ml) with ml0 | ml0
· rw [ml0, mul_zero, Nat.le_zero] at mm₂
rw [ml0, mm₂] at mm; cases mm (by decide)
have : 2 * size l ≤ size ml + size mr + 1 := by
have := Nat.mul_le_mul_left ratio lr₁
rw [mul_left_comm, mul_add] at this
have := le_trans this (add_le_add_left mr₁ _)
rw [← Nat.succ_mul] at this
exact (mul_le_mul_left (by decide)).1 this
refine ⟨Or.inr ⟨?_, ?_⟩, Or.inr ⟨?_, ?_⟩, Or.inr ⟨?_, ?_⟩⟩
· refine (mul_le_mul_left (by decide)).1 (le_trans this ?_)
rw [two_mul, Nat.succ_le_iff]
refine add_lt_add_of_lt_of_le ?_ mm₂
simpa using (mul_lt_mul_right ml0).2 (by decide : 1 < 3)
· exact Nat.le_of_lt_succ (Valid'.node4L_lemma₁ lr₂ mr₂ mm₁)
· exact Valid'.node4L_lemma₂ mr₂
· exact Valid'.node4L_lemma₃ mr₁ mm₁
· exact Valid'.node4L_lemma₄ lr₁ mr₂ mm₁
· exact Valid'.node4L_lemma₅ lr₂ mr₁ mm₂
#align ordnode.valid'.node4_l Ordnode.Valid'.node4L
theorem Valid'.rotateL_lemma₁ {a b c : ℕ} (H2 : 3 * a ≤ b + c) (hb₂ : c ≤ 3 * b) : a ≤ 3 * b := by
omega
#align ordnode.valid'.rotate_l_lemma₁ Ordnode.Valid'.rotateL_lemma₁
| Mathlib/Data/Ordmap/Ordset.lean | 1,225 | 1,226 | theorem Valid'.rotateL_lemma₂ {a b c : ℕ} (H3 : 2 * (b + c) ≤ 9 * a + 3) (h : b < 2 * c) :
b < 3 * a + 1 := by | omega
|
import Mathlib.Analysis.Calculus.ContDiff.Basic
import Mathlib.Analysis.Calculus.UniformLimitsDeriv
import Mathlib.Topology.Algebra.InfiniteSum.Module
import Mathlib.Analysis.NormedSpace.FunctionSeries
#align_import analysis.calculus.series from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982"
open Set Metric TopologicalSpace Function Asymptotics Filter
open scoped Topology NNReal
variable {α β 𝕜 E F : Type*} [RCLike 𝕜] [NormedAddCommGroup E] [NormedSpace 𝕜 E]
[NormedAddCommGroup F] [CompleteSpace F] {u : α → ℝ}
variable [NormedSpace 𝕜 F]
variable {f : α → E → F} {f' : α → E → E →L[𝕜] F} {g : α → 𝕜 → F} {g' : α → 𝕜 → F} {v : ℕ → α → ℝ}
{s : Set E} {t : Set 𝕜} {x₀ x : E} {y₀ y : 𝕜} {N : ℕ∞}
theorem summable_of_summable_hasFDerivAt_of_isPreconnected (hu : Summable u) (hs : IsOpen s)
(h's : IsPreconnected s) (hf : ∀ n x, x ∈ s → HasFDerivAt (f n) (f' n x) x)
(hf' : ∀ n x, x ∈ s → ‖f' n x‖ ≤ u n) (hx₀ : x₀ ∈ s) (hf0 : Summable (f · x₀))
(hx : x ∈ s) : Summable fun n => f n x := by
haveI := Classical.decEq α
rw [summable_iff_cauchySeq_finset] at hf0 ⊢
have A : UniformCauchySeqOn (fun t : Finset α => fun x => ∑ i ∈ t, f' i x) atTop s :=
(tendstoUniformlyOn_tsum hu hf').uniformCauchySeqOn
-- Porting note: Lean 4 failed to find `f` by unification
refine cauchy_map_of_uniformCauchySeqOn_fderiv (f := fun t x ↦ ∑ i ∈ t, f i x)
hs h's A (fun t y hy => ?_) hx₀ hx hf0
exact HasFDerivAt.sum fun i _ => hf i y hy
#align summable_of_summable_has_fderiv_at_of_is_preconnected summable_of_summable_hasFDerivAt_of_isPreconnected
| Mathlib/Analysis/Calculus/SmoothSeries.lean | 60 | 66 | theorem summable_of_summable_hasDerivAt_of_isPreconnected (hu : Summable u) (ht : IsOpen t)
(h't : IsPreconnected t) (hg : ∀ n y, y ∈ t → HasDerivAt (g n) (g' n y) y)
(hg' : ∀ n y, y ∈ t → ‖g' n y‖ ≤ u n) (hy₀ : y₀ ∈ t) (hg0 : Summable (g · y₀))
(hy : y ∈ t) : Summable fun n => g n y := by |
simp_rw [hasDerivAt_iff_hasFDerivAt] at hg
refine summable_of_summable_hasFDerivAt_of_isPreconnected hu ht h't hg ?_ hy₀ hg0 hy
simpa? says simpa only [ContinuousLinearMap.norm_smulRight_apply, norm_one, one_mul]
|
import Mathlib.Probability.Kernel.MeasurableIntegral
#align_import probability.kernel.composition from "leanprover-community/mathlib"@"3b92d54a05ee592aa2c6181a4e76b1bb7cc45d0b"
open MeasureTheory
open scoped ENNReal
namespace ProbabilityTheory
namespace kernel
variable {α β ι : Type*} {mα : MeasurableSpace α} {mβ : MeasurableSpace β}
section CompositionProduct
variable {γ : Type*} {mγ : MeasurableSpace γ} {s : Set (β × γ)}
noncomputable def compProdFun (κ : kernel α β) (η : kernel (α × β) γ) (a : α) (s : Set (β × γ)) :
ℝ≥0∞ :=
∫⁻ b, η (a, b) {c | (b, c) ∈ s} ∂κ a
#align probability_theory.kernel.comp_prod_fun ProbabilityTheory.kernel.compProdFun
theorem compProdFun_empty (κ : kernel α β) (η : kernel (α × β) γ) (a : α) :
compProdFun κ η a ∅ = 0 := by
simp only [compProdFun, Set.mem_empty_iff_false, Set.setOf_false, measure_empty,
MeasureTheory.lintegral_const, zero_mul]
#align probability_theory.kernel.comp_prod_fun_empty ProbabilityTheory.kernel.compProdFun_empty
theorem compProdFun_iUnion (κ : kernel α β) (η : kernel (α × β) γ) [IsSFiniteKernel η] (a : α)
(f : ℕ → Set (β × γ)) (hf_meas : ∀ i, MeasurableSet (f i))
(hf_disj : Pairwise (Disjoint on f)) :
compProdFun κ η a (⋃ i, f i) = ∑' i, compProdFun κ η a (f i) := by
have h_Union :
(fun b => η (a, b) {c : γ | (b, c) ∈ ⋃ i, f i}) = fun b =>
η (a, b) (⋃ i, {c : γ | (b, c) ∈ f i}) := by
ext1 b
congr with c
simp only [Set.mem_iUnion, Set.iSup_eq_iUnion, Set.mem_setOf_eq]
rw [compProdFun, h_Union]
have h_tsum :
(fun b => η (a, b) (⋃ i, {c : γ | (b, c) ∈ f i})) = fun b =>
∑' i, η (a, b) {c : γ | (b, c) ∈ f i} := by
ext1 b
rw [measure_iUnion]
· intro i j hij s hsi hsj c hcs
have hbci : {(b, c)} ⊆ f i := by rw [Set.singleton_subset_iff]; exact hsi hcs
have hbcj : {(b, c)} ⊆ f j := by rw [Set.singleton_subset_iff]; exact hsj hcs
simpa only [Set.bot_eq_empty, Set.le_eq_subset, Set.singleton_subset_iff,
Set.mem_empty_iff_false] using hf_disj hij hbci hbcj
· -- Porting note: behavior of `@` changed relative to lean 3, was
-- exact fun i => (@measurable_prod_mk_left β γ _ _ b) _ (hf_meas i)
exact fun i => (@measurable_prod_mk_left β γ _ _ b) (hf_meas i)
rw [h_tsum, lintegral_tsum]
· rfl
· intro i
have hm : MeasurableSet {p : (α × β) × γ | (p.1.2, p.2) ∈ f i} :=
measurable_fst.snd.prod_mk measurable_snd (hf_meas i)
exact ((measurable_kernel_prod_mk_left hm).comp measurable_prod_mk_left).aemeasurable
#align probability_theory.kernel.comp_prod_fun_Union ProbabilityTheory.kernel.compProdFun_iUnion
theorem compProdFun_tsum_right (κ : kernel α β) (η : kernel (α × β) γ) [IsSFiniteKernel η] (a : α)
(hs : MeasurableSet s) : compProdFun κ η a s = ∑' n, compProdFun κ (seq η n) a s := by
simp_rw [compProdFun, (measure_sum_seq η _).symm]
have :
∫⁻ b, Measure.sum (fun n => seq η n (a, b)) {c : γ | (b, c) ∈ s} ∂κ a =
∫⁻ b, ∑' n, seq η n (a, b) {c : γ | (b, c) ∈ s} ∂κ a := by
congr
ext1 b
rw [Measure.sum_apply]
exact measurable_prod_mk_left hs
rw [this, lintegral_tsum]
exact fun n => ((measurable_kernel_prod_mk_left (κ := (seq η n))
((measurable_fst.snd.prod_mk measurable_snd) hs)).comp measurable_prod_mk_left).aemeasurable
#align probability_theory.kernel.comp_prod_fun_tsum_right ProbabilityTheory.kernel.compProdFun_tsum_right
theorem compProdFun_tsum_left (κ : kernel α β) (η : kernel (α × β) γ) [IsSFiniteKernel κ] (a : α)
(s : Set (β × γ)) : compProdFun κ η a s = ∑' n, compProdFun (seq κ n) η a s := by
simp_rw [compProdFun, (measure_sum_seq κ _).symm, lintegral_sum_measure]
#align probability_theory.kernel.comp_prod_fun_tsum_left ProbabilityTheory.kernel.compProdFun_tsum_left
theorem compProdFun_eq_tsum (κ : kernel α β) [IsSFiniteKernel κ] (η : kernel (α × β) γ)
[IsSFiniteKernel η] (a : α) (hs : MeasurableSet s) :
compProdFun κ η a s = ∑' (n) (m), compProdFun (seq κ n) (seq η m) a s := by
simp_rw [compProdFun_tsum_left κ η a s, compProdFun_tsum_right _ η a hs]
#align probability_theory.kernel.comp_prod_fun_eq_tsum ProbabilityTheory.kernel.compProdFun_eq_tsum
theorem measurable_compProdFun_of_finite (κ : kernel α β) [IsFiniteKernel κ] (η : kernel (α × β) γ)
[IsFiniteKernel η] (hs : MeasurableSet s) : Measurable fun a => compProdFun κ η a s := by
simp only [compProdFun]
have h_meas : Measurable (Function.uncurry fun a b => η (a, b) {c : γ | (b, c) ∈ s}) := by
have :
(Function.uncurry fun a b => η (a, b) {c : γ | (b, c) ∈ s}) = fun p =>
η p {c : γ | (p.2, c) ∈ s} := by
ext1 p
rw [Function.uncurry_apply_pair]
rw [this]
exact measurable_kernel_prod_mk_left (measurable_fst.snd.prod_mk measurable_snd hs)
exact h_meas.lintegral_kernel_prod_right
#align probability_theory.kernel.measurable_comp_prod_fun_of_finite ProbabilityTheory.kernel.measurable_compProdFun_of_finite
theorem measurable_compProdFun (κ : kernel α β) [IsSFiniteKernel κ] (η : kernel (α × β) γ)
[IsSFiniteKernel η] (hs : MeasurableSet s) : Measurable fun a => compProdFun κ η a s := by
simp_rw [compProdFun_tsum_right κ η _ hs]
refine Measurable.ennreal_tsum fun n => ?_
simp only [compProdFun]
have h_meas : Measurable (Function.uncurry fun a b => seq η n (a, b) {c : γ | (b, c) ∈ s}) := by
have :
(Function.uncurry fun a b => seq η n (a, b) {c : γ | (b, c) ∈ s}) = fun p =>
seq η n p {c : γ | (p.2, c) ∈ s} := by
ext1 p
rw [Function.uncurry_apply_pair]
rw [this]
exact measurable_kernel_prod_mk_left (measurable_fst.snd.prod_mk measurable_snd hs)
exact h_meas.lintegral_kernel_prod_right
#align probability_theory.kernel.measurable_comp_prod_fun ProbabilityTheory.kernel.measurable_compProdFun
open scoped Classical
noncomputable def compProd (κ : kernel α β) (η : kernel (α × β) γ) : kernel α (β × γ) :=
if h : IsSFiniteKernel κ ∧ IsSFiniteKernel η then
{ val := fun a ↦
Measure.ofMeasurable (fun s _ => compProdFun κ η a s) (compProdFun_empty κ η a)
(@compProdFun_iUnion _ _ _ _ _ _ κ η h.2 a)
property := by
have : IsSFiniteKernel κ := h.1
have : IsSFiniteKernel η := h.2
refine Measure.measurable_of_measurable_coe _ fun s hs => ?_
have :
(fun a =>
Measure.ofMeasurable (fun s _ => compProdFun κ η a s) (compProdFun_empty κ η a)
(compProdFun_iUnion κ η a) s) =
fun a => compProdFun κ η a s := by
ext1 a; rwa [Measure.ofMeasurable_apply]
rw [this]
exact measurable_compProdFun κ η hs }
else 0
#align probability_theory.kernel.comp_prod ProbabilityTheory.kernel.compProd
scoped[ProbabilityTheory] infixl:100 " ⊗ₖ " => ProbabilityTheory.kernel.compProd
theorem compProd_apply_eq_compProdFun (κ : kernel α β) [IsSFiniteKernel κ] (η : kernel (α × β) γ)
[IsSFiniteKernel η] (a : α) (hs : MeasurableSet s) :
(κ ⊗ₖ η) a s = compProdFun κ η a s := by
rw [compProd, dif_pos]
swap
· constructor <;> infer_instance
change
Measure.ofMeasurable (fun s _ => compProdFun κ η a s) (compProdFun_empty κ η a)
(compProdFun_iUnion κ η a) s =
∫⁻ b, η (a, b) {c | (b, c) ∈ s} ∂κ a
rw [Measure.ofMeasurable_apply _ hs]
rfl
#align probability_theory.kernel.comp_prod_apply_eq_comp_prod_fun ProbabilityTheory.kernel.compProd_apply_eq_compProdFun
theorem compProd_of_not_isSFiniteKernel_left (κ : kernel α β) (η : kernel (α × β) γ)
(h : ¬ IsSFiniteKernel κ) :
κ ⊗ₖ η = 0 := by
rw [compProd, dif_neg]
simp [h]
theorem compProd_of_not_isSFiniteKernel_right (κ : kernel α β) (η : kernel (α × β) γ)
(h : ¬ IsSFiniteKernel η) :
κ ⊗ₖ η = 0 := by
rw [compProd, dif_neg]
simp [h]
theorem compProd_apply (κ : kernel α β) [IsSFiniteKernel κ] (η : kernel (α × β) γ)
[IsSFiniteKernel η] (a : α) (hs : MeasurableSet s) :
(κ ⊗ₖ η) a s = ∫⁻ b, η (a, b) {c | (b, c) ∈ s} ∂κ a :=
compProd_apply_eq_compProdFun κ η a hs
#align probability_theory.kernel.comp_prod_apply ProbabilityTheory.kernel.compProd_apply
theorem le_compProd_apply (κ : kernel α β) [IsSFiniteKernel κ] (η : kernel (α × β) γ)
[IsSFiniteKernel η] (a : α) (s : Set (β × γ)) :
∫⁻ b, η (a, b) {c | (b, c) ∈ s} ∂κ a ≤ (κ ⊗ₖ η) a s :=
calc
∫⁻ b, η (a, b) {c | (b, c) ∈ s} ∂κ a ≤
∫⁻ b, η (a, b) {c | (b, c) ∈ toMeasurable ((κ ⊗ₖ η) a) s} ∂κ a :=
lintegral_mono fun _ => measure_mono fun _ h_mem => subset_toMeasurable _ _ h_mem
_ = (κ ⊗ₖ η) a (toMeasurable ((κ ⊗ₖ η) a) s) :=
(kernel.compProd_apply_eq_compProdFun κ η a (measurableSet_toMeasurable _ _)).symm
_ = (κ ⊗ₖ η) a s := measure_toMeasurable s
#align probability_theory.kernel.le_comp_prod_apply ProbabilityTheory.kernel.le_compProd_apply
@[simp]
lemma compProd_zero_left (κ : kernel (α × β) γ) :
(0 : kernel α β) ⊗ₖ κ = 0 := by
by_cases h : IsSFiniteKernel κ
· ext a s hs
rw [kernel.compProd_apply _ _ _ hs]
simp
· rw [kernel.compProd_of_not_isSFiniteKernel_right _ _ h]
@[simp]
lemma compProd_zero_right (κ : kernel α β) (γ : Type*) [MeasurableSpace γ] :
κ ⊗ₖ (0 : kernel (α × β) γ) = 0 := by
by_cases h : IsSFiniteKernel κ
· ext a s hs
rw [kernel.compProd_apply _ _ _ hs]
simp
· rw [kernel.compProd_of_not_isSFiniteKernel_left _ _ h]
section Lintegral
theorem lintegral_compProd' (κ : kernel α β) [IsSFiniteKernel κ] (η : kernel (α × β) γ)
[IsSFiniteKernel η] (a : α) {f : β → γ → ℝ≥0∞} (hf : Measurable (Function.uncurry f)) :
∫⁻ bc, f bc.1 bc.2 ∂(κ ⊗ₖ η) a = ∫⁻ b, ∫⁻ c, f b c ∂η (a, b) ∂κ a := by
let F : ℕ → SimpleFunc (β × γ) ℝ≥0∞ := SimpleFunc.eapprox (Function.uncurry f)
have h : ∀ a, ⨆ n, F n a = Function.uncurry f a :=
SimpleFunc.iSup_eapprox_apply (Function.uncurry f) hf
simp only [Prod.forall, Function.uncurry_apply_pair] at h
simp_rw [← h]
have h_mono : Monotone F := fun i j hij b =>
SimpleFunc.monotone_eapprox (Function.uncurry f) hij _
rw [lintegral_iSup (fun n => (F n).measurable) h_mono]
have : ∀ b, ∫⁻ c, ⨆ n, F n (b, c) ∂η (a, b) = ⨆ n, ∫⁻ c, F n (b, c) ∂η (a, b) := by
intro a
rw [lintegral_iSup]
· exact fun n => (F n).measurable.comp measurable_prod_mk_left
· exact fun i j hij b => h_mono hij _
simp_rw [this]
have h_some_meas_integral :
∀ f' : SimpleFunc (β × γ) ℝ≥0∞, Measurable fun b => ∫⁻ c, f' (b, c) ∂η (a, b) := by
intro f'
have :
(fun b => ∫⁻ c, f' (b, c) ∂η (a, b)) =
(fun ab => ∫⁻ c, f' (ab.2, c) ∂η ab) ∘ fun b => (a, b) := by
ext1 ab; rfl
rw [this]
apply Measurable.comp _ (measurable_prod_mk_left (m := mα))
exact Measurable.lintegral_kernel_prod_right
((SimpleFunc.measurable _).comp (measurable_fst.snd.prod_mk measurable_snd))
rw [lintegral_iSup]
rotate_left
· exact fun n => h_some_meas_integral (F n)
· exact fun i j hij b => lintegral_mono fun c => h_mono hij _
congr
ext1 n
-- Porting note: Added `(P := _)`
refine SimpleFunc.induction (P := fun f => (∫⁻ (a : β × γ), f a ∂(κ ⊗ₖ η) a =
∫⁻ (a_1 : β), ∫⁻ (c : γ), f (a_1, c) ∂η (a, a_1) ∂κ a)) ?_ ?_ (F n)
· intro c s hs
classical -- Porting note: Added `classical` for `Set.piecewise_eq_indicator`
simp (config := { unfoldPartialApp := true }) only [SimpleFunc.const_zero,
SimpleFunc.coe_piecewise, SimpleFunc.coe_const, SimpleFunc.coe_zero,
Set.piecewise_eq_indicator, Function.const, lintegral_indicator_const hs]
rw [compProd_apply κ η _ hs, ← lintegral_const_mul c _]
swap
· exact (measurable_kernel_prod_mk_left ((measurable_fst.snd.prod_mk measurable_snd) hs)).comp
measurable_prod_mk_left
congr
ext1 b
rw [lintegral_indicator_const_comp measurable_prod_mk_left hs]
rfl
· intro f f' _ hf_eq hf'_eq
simp_rw [SimpleFunc.coe_add, Pi.add_apply]
change
∫⁻ x, (f : β × γ → ℝ≥0∞) x + f' x ∂(κ ⊗ₖ η) a =
∫⁻ b, ∫⁻ c : γ, f (b, c) + f' (b, c) ∂η (a, b) ∂κ a
rw [lintegral_add_left (SimpleFunc.measurable _), hf_eq, hf'_eq, ← lintegral_add_left]
swap
· exact h_some_meas_integral f
congr with b
rw [lintegral_add_left]
exact (SimpleFunc.measurable _).comp measurable_prod_mk_left
#align probability_theory.kernel.lintegral_comp_prod' ProbabilityTheory.kernel.lintegral_compProd'
| Mathlib/Probability/Kernel/Composition.lean | 446 | 453 | theorem lintegral_compProd (κ : kernel α β) [IsSFiniteKernel κ] (η : kernel (α × β) γ)
[IsSFiniteKernel η] (a : α) {f : β × γ → ℝ≥0∞} (hf : Measurable f) :
∫⁻ bc, f bc ∂(κ ⊗ₖ η) a = ∫⁻ b, ∫⁻ c, f (b, c) ∂η (a, b) ∂κ a := by |
let g := Function.curry f
change ∫⁻ bc, f bc ∂(κ ⊗ₖ η) a = ∫⁻ b, ∫⁻ c, g b c ∂η (a, b) ∂κ a
rw [← lintegral_compProd']
· simp_rw [g, Function.curry_apply]
· simp_rw [g, Function.uncurry_curry]; exact hf
|
import Mathlib.Analysis.InnerProductSpace.TwoDim
import Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic
#align_import geometry.euclidean.angle.oriented.basic from "leanprover-community/mathlib"@"f0c8bf9245297a541f468be517f1bde6195105e9"
noncomputable section
open FiniteDimensional Complex
open scoped Real RealInnerProductSpace ComplexConjugate
namespace Orientation
attribute [local instance] Complex.finrank_real_complex_fact
variable {V V' : Type*}
variable [NormedAddCommGroup V] [NormedAddCommGroup V']
variable [InnerProductSpace ℝ V] [InnerProductSpace ℝ V']
variable [Fact (finrank ℝ V = 2)] [Fact (finrank ℝ V' = 2)] (o : Orientation ℝ V (Fin 2))
local notation "ω" => o.areaForm
def oangle (x y : V) : Real.Angle :=
Complex.arg (o.kahler x y)
#align orientation.oangle Orientation.oangle
theorem continuousAt_oangle {x : V × V} (hx1 : x.1 ≠ 0) (hx2 : x.2 ≠ 0) :
ContinuousAt (fun y : V × V => o.oangle y.1 y.2) x := by
refine (Complex.continuousAt_arg_coe_angle ?_).comp ?_
· exact o.kahler_ne_zero hx1 hx2
exact ((continuous_ofReal.comp continuous_inner).add
((continuous_ofReal.comp o.areaForm'.continuous₂).mul continuous_const)).continuousAt
#align orientation.continuous_at_oangle Orientation.continuousAt_oangle
@[simp]
theorem oangle_zero_left (x : V) : o.oangle 0 x = 0 := by simp [oangle]
#align orientation.oangle_zero_left Orientation.oangle_zero_left
@[simp]
theorem oangle_zero_right (x : V) : o.oangle x 0 = 0 := by simp [oangle]
#align orientation.oangle_zero_right Orientation.oangle_zero_right
@[simp]
theorem oangle_self (x : V) : o.oangle x x = 0 := by
rw [oangle, kahler_apply_self, ← ofReal_pow]
convert QuotientAddGroup.mk_zero (AddSubgroup.zmultiples (2 * π))
apply arg_ofReal_of_nonneg
positivity
#align orientation.oangle_self Orientation.oangle_self
theorem left_ne_zero_of_oangle_ne_zero {x y : V} (h : o.oangle x y ≠ 0) : x ≠ 0 := by
rintro rfl; simp at h
#align orientation.left_ne_zero_of_oangle_ne_zero Orientation.left_ne_zero_of_oangle_ne_zero
theorem right_ne_zero_of_oangle_ne_zero {x y : V} (h : o.oangle x y ≠ 0) : y ≠ 0 := by
rintro rfl; simp at h
#align orientation.right_ne_zero_of_oangle_ne_zero Orientation.right_ne_zero_of_oangle_ne_zero
theorem ne_of_oangle_ne_zero {x y : V} (h : o.oangle x y ≠ 0) : x ≠ y := by
rintro rfl; simp at h
#align orientation.ne_of_oangle_ne_zero Orientation.ne_of_oangle_ne_zero
theorem left_ne_zero_of_oangle_eq_pi {x y : V} (h : o.oangle x y = π) : x ≠ 0 :=
o.left_ne_zero_of_oangle_ne_zero (h.symm ▸ Real.Angle.pi_ne_zero : o.oangle x y ≠ 0)
#align orientation.left_ne_zero_of_oangle_eq_pi Orientation.left_ne_zero_of_oangle_eq_pi
theorem right_ne_zero_of_oangle_eq_pi {x y : V} (h : o.oangle x y = π) : y ≠ 0 :=
o.right_ne_zero_of_oangle_ne_zero (h.symm ▸ Real.Angle.pi_ne_zero : o.oangle x y ≠ 0)
#align orientation.right_ne_zero_of_oangle_eq_pi Orientation.right_ne_zero_of_oangle_eq_pi
theorem ne_of_oangle_eq_pi {x y : V} (h : o.oangle x y = π) : x ≠ y :=
o.ne_of_oangle_ne_zero (h.symm ▸ Real.Angle.pi_ne_zero : o.oangle x y ≠ 0)
#align orientation.ne_of_oangle_eq_pi Orientation.ne_of_oangle_eq_pi
theorem left_ne_zero_of_oangle_eq_pi_div_two {x y : V} (h : o.oangle x y = (π / 2 : ℝ)) : x ≠ 0 :=
o.left_ne_zero_of_oangle_ne_zero (h.symm ▸ Real.Angle.pi_div_two_ne_zero : o.oangle x y ≠ 0)
#align orientation.left_ne_zero_of_oangle_eq_pi_div_two Orientation.left_ne_zero_of_oangle_eq_pi_div_two
theorem right_ne_zero_of_oangle_eq_pi_div_two {x y : V} (h : o.oangle x y = (π / 2 : ℝ)) : y ≠ 0 :=
o.right_ne_zero_of_oangle_ne_zero (h.symm ▸ Real.Angle.pi_div_two_ne_zero : o.oangle x y ≠ 0)
#align orientation.right_ne_zero_of_oangle_eq_pi_div_two Orientation.right_ne_zero_of_oangle_eq_pi_div_two
theorem ne_of_oangle_eq_pi_div_two {x y : V} (h : o.oangle x y = (π / 2 : ℝ)) : x ≠ y :=
o.ne_of_oangle_ne_zero (h.symm ▸ Real.Angle.pi_div_two_ne_zero : o.oangle x y ≠ 0)
#align orientation.ne_of_oangle_eq_pi_div_two Orientation.ne_of_oangle_eq_pi_div_two
theorem left_ne_zero_of_oangle_eq_neg_pi_div_two {x y : V} (h : o.oangle x y = (-π / 2 : ℝ)) :
x ≠ 0 :=
o.left_ne_zero_of_oangle_ne_zero (h.symm ▸ Real.Angle.neg_pi_div_two_ne_zero : o.oangle x y ≠ 0)
#align orientation.left_ne_zero_of_oangle_eq_neg_pi_div_two Orientation.left_ne_zero_of_oangle_eq_neg_pi_div_two
theorem right_ne_zero_of_oangle_eq_neg_pi_div_two {x y : V} (h : o.oangle x y = (-π / 2 : ℝ)) :
y ≠ 0 :=
o.right_ne_zero_of_oangle_ne_zero (h.symm ▸ Real.Angle.neg_pi_div_two_ne_zero : o.oangle x y ≠ 0)
#align orientation.right_ne_zero_of_oangle_eq_neg_pi_div_two Orientation.right_ne_zero_of_oangle_eq_neg_pi_div_two
theorem ne_of_oangle_eq_neg_pi_div_two {x y : V} (h : o.oangle x y = (-π / 2 : ℝ)) : x ≠ y :=
o.ne_of_oangle_ne_zero (h.symm ▸ Real.Angle.neg_pi_div_two_ne_zero : o.oangle x y ≠ 0)
#align orientation.ne_of_oangle_eq_neg_pi_div_two Orientation.ne_of_oangle_eq_neg_pi_div_two
theorem left_ne_zero_of_oangle_sign_ne_zero {x y : V} (h : (o.oangle x y).sign ≠ 0) : x ≠ 0 :=
o.left_ne_zero_of_oangle_ne_zero (Real.Angle.sign_ne_zero_iff.1 h).1
#align orientation.left_ne_zero_of_oangle_sign_ne_zero Orientation.left_ne_zero_of_oangle_sign_ne_zero
theorem right_ne_zero_of_oangle_sign_ne_zero {x y : V} (h : (o.oangle x y).sign ≠ 0) : y ≠ 0 :=
o.right_ne_zero_of_oangle_ne_zero (Real.Angle.sign_ne_zero_iff.1 h).1
#align orientation.right_ne_zero_of_oangle_sign_ne_zero Orientation.right_ne_zero_of_oangle_sign_ne_zero
theorem ne_of_oangle_sign_ne_zero {x y : V} (h : (o.oangle x y).sign ≠ 0) : x ≠ y :=
o.ne_of_oangle_ne_zero (Real.Angle.sign_ne_zero_iff.1 h).1
#align orientation.ne_of_oangle_sign_ne_zero Orientation.ne_of_oangle_sign_ne_zero
theorem left_ne_zero_of_oangle_sign_eq_one {x y : V} (h : (o.oangle x y).sign = 1) : x ≠ 0 :=
o.left_ne_zero_of_oangle_sign_ne_zero (h.symm ▸ by decide : (o.oangle x y).sign ≠ 0)
#align orientation.left_ne_zero_of_oangle_sign_eq_one Orientation.left_ne_zero_of_oangle_sign_eq_one
theorem right_ne_zero_of_oangle_sign_eq_one {x y : V} (h : (o.oangle x y).sign = 1) : y ≠ 0 :=
o.right_ne_zero_of_oangle_sign_ne_zero (h.symm ▸ by decide : (o.oangle x y).sign ≠ 0)
#align orientation.right_ne_zero_of_oangle_sign_eq_one Orientation.right_ne_zero_of_oangle_sign_eq_one
theorem ne_of_oangle_sign_eq_one {x y : V} (h : (o.oangle x y).sign = 1) : x ≠ y :=
o.ne_of_oangle_sign_ne_zero (h.symm ▸ by decide : (o.oangle x y).sign ≠ 0)
#align orientation.ne_of_oangle_sign_eq_one Orientation.ne_of_oangle_sign_eq_one
theorem left_ne_zero_of_oangle_sign_eq_neg_one {x y : V} (h : (o.oangle x y).sign = -1) : x ≠ 0 :=
o.left_ne_zero_of_oangle_sign_ne_zero (h.symm ▸ by decide : (o.oangle x y).sign ≠ 0)
#align orientation.left_ne_zero_of_oangle_sign_eq_neg_one Orientation.left_ne_zero_of_oangle_sign_eq_neg_one
theorem right_ne_zero_of_oangle_sign_eq_neg_one {x y : V} (h : (o.oangle x y).sign = -1) : y ≠ 0 :=
o.right_ne_zero_of_oangle_sign_ne_zero (h.symm ▸ by decide : (o.oangle x y).sign ≠ 0)
#align orientation.right_ne_zero_of_oangle_sign_eq_neg_one Orientation.right_ne_zero_of_oangle_sign_eq_neg_one
theorem ne_of_oangle_sign_eq_neg_one {x y : V} (h : (o.oangle x y).sign = -1) : x ≠ y :=
o.ne_of_oangle_sign_ne_zero (h.symm ▸ by decide : (o.oangle x y).sign ≠ 0)
#align orientation.ne_of_oangle_sign_eq_neg_one Orientation.ne_of_oangle_sign_eq_neg_one
| Mathlib/Geometry/Euclidean/Angle/Oriented/Basic.lean | 193 | 194 | theorem oangle_rev (x y : V) : o.oangle y x = -o.oangle x y := by |
simp only [oangle, o.kahler_swap y x, Complex.arg_conj_coe_angle]
|
import Mathlib.Algebra.Category.ModuleCat.Free
import Mathlib.Topology.Category.Profinite.CofilteredLimit
import Mathlib.Topology.Category.Profinite.Product
import Mathlib.Topology.LocallyConstant.Algebra
import Mathlib.Init.Data.Bool.Lemmas
universe u
namespace Profinite
namespace NobelingProof
variable {I : Type u} [LinearOrder I] [IsWellOrder I (·<·)] (C : Set (I → Bool))
open Profinite ContinuousMap CategoryTheory Limits Opposite Submodule
section Projections
variable (J K L : I → Prop) [∀ i, Decidable (J i)] [∀ i, Decidable (K i)] [∀ i, Decidable (L i)]
def Proj : (I → Bool) → (I → Bool) :=
fun c i ↦ if J i then c i else false
@[simp]
theorem continuous_proj :
Continuous (Proj J : (I → Bool) → (I → Bool)) := by
dsimp (config := { unfoldPartialApp := true }) [Proj]
apply continuous_pi
intro i
split
· apply continuous_apply
· apply continuous_const
def π : Set (I → Bool) := (Proj J) '' C
@[simps!]
def ProjRestrict : C → π C J :=
Set.MapsTo.restrict (Proj J) _ _ (Set.mapsTo_image _ _)
@[simp]
theorem continuous_projRestrict : Continuous (ProjRestrict C J) :=
Continuous.restrict _ (continuous_proj _)
| Mathlib/Topology/Category/Profinite/Nobeling.lean | 113 | 117 | theorem proj_eq_self {x : I → Bool} (h : ∀ i, x i ≠ false → J i) : Proj J x = x := by |
ext i
simp only [Proj, ite_eq_left_iff]
contrapose!
simpa only [ne_comm] using h i
|
import Mathlib.Data.ENNReal.Inv
#align_import data.real.ennreal from "leanprover-community/mathlib"@"c14c8fcde993801fca8946b0d80131a1a81d1520"
open Set NNReal ENNReal
namespace ENNReal
section Real
variable {a b c d : ℝ≥0∞} {r p q : ℝ≥0}
theorem toReal_add (ha : a ≠ ∞) (hb : b ≠ ∞) : (a + b).toReal = a.toReal + b.toReal := by
lift a to ℝ≥0 using ha
lift b to ℝ≥0 using hb
rfl
#align ennreal.to_real_add ENNReal.toReal_add
theorem toReal_sub_of_le {a b : ℝ≥0∞} (h : b ≤ a) (ha : a ≠ ∞) :
(a - b).toReal = a.toReal - b.toReal := by
lift b to ℝ≥0 using ne_top_of_le_ne_top ha h
lift a to ℝ≥0 using ha
simp only [← ENNReal.coe_sub, ENNReal.coe_toReal, NNReal.coe_sub (ENNReal.coe_le_coe.mp h)]
#align ennreal.to_real_sub_of_le ENNReal.toReal_sub_of_le
theorem le_toReal_sub {a b : ℝ≥0∞} (hb : b ≠ ∞) : a.toReal - b.toReal ≤ (a - b).toReal := by
lift b to ℝ≥0 using hb
induction a
· simp
· simp only [← coe_sub, NNReal.sub_def, Real.coe_toNNReal', coe_toReal]
exact le_max_left _ _
#align ennreal.le_to_real_sub ENNReal.le_toReal_sub
theorem toReal_add_le : (a + b).toReal ≤ a.toReal + b.toReal :=
if ha : a = ∞ then by simp only [ha, top_add, top_toReal, zero_add, toReal_nonneg]
else
if hb : b = ∞ then by simp only [hb, add_top, top_toReal, add_zero, toReal_nonneg]
else le_of_eq (toReal_add ha hb)
#align ennreal.to_real_add_le ENNReal.toReal_add_le
theorem ofReal_add {p q : ℝ} (hp : 0 ≤ p) (hq : 0 ≤ q) :
ENNReal.ofReal (p + q) = ENNReal.ofReal p + ENNReal.ofReal q := by
rw [ENNReal.ofReal, ENNReal.ofReal, ENNReal.ofReal, ← coe_add, coe_inj,
Real.toNNReal_add hp hq]
#align ennreal.of_real_add ENNReal.ofReal_add
theorem ofReal_add_le {p q : ℝ} : ENNReal.ofReal (p + q) ≤ ENNReal.ofReal p + ENNReal.ofReal q :=
coe_le_coe.2 Real.toNNReal_add_le
#align ennreal.of_real_add_le ENNReal.ofReal_add_le
@[simp]
theorem toReal_le_toReal (ha : a ≠ ∞) (hb : b ≠ ∞) : a.toReal ≤ b.toReal ↔ a ≤ b := by
lift a to ℝ≥0 using ha
lift b to ℝ≥0 using hb
norm_cast
#align ennreal.to_real_le_to_real ENNReal.toReal_le_toReal
@[gcongr]
theorem toReal_mono (hb : b ≠ ∞) (h : a ≤ b) : a.toReal ≤ b.toReal :=
(toReal_le_toReal (ne_top_of_le_ne_top hb h) hb).2 h
#align ennreal.to_real_mono ENNReal.toReal_mono
-- Porting note (#10756): new lemma
theorem toReal_mono' (h : a ≤ b) (ht : b = ∞ → a = ∞) : a.toReal ≤ b.toReal := by
rcases eq_or_ne a ∞ with rfl | ha
· exact toReal_nonneg
· exact toReal_mono (mt ht ha) h
@[simp]
theorem toReal_lt_toReal (ha : a ≠ ∞) (hb : b ≠ ∞) : a.toReal < b.toReal ↔ a < b := by
lift a to ℝ≥0 using ha
lift b to ℝ≥0 using hb
norm_cast
#align ennreal.to_real_lt_to_real ENNReal.toReal_lt_toReal
@[gcongr]
theorem toReal_strict_mono (hb : b ≠ ∞) (h : a < b) : a.toReal < b.toReal :=
(toReal_lt_toReal h.ne_top hb).2 h
#align ennreal.to_real_strict_mono ENNReal.toReal_strict_mono
@[gcongr]
theorem toNNReal_mono (hb : b ≠ ∞) (h : a ≤ b) : a.toNNReal ≤ b.toNNReal :=
toReal_mono hb h
#align ennreal.to_nnreal_mono ENNReal.toNNReal_mono
-- Porting note (#10756): new lemma
theorem toReal_le_add' (hle : a ≤ b + c) (hb : b = ∞ → a = ∞) (hc : c = ∞ → a = ∞) :
a.toReal ≤ b.toReal + c.toReal := by
refine le_trans (toReal_mono' hle ?_) toReal_add_le
simpa only [add_eq_top, or_imp] using And.intro hb hc
-- Porting note (#10756): new lemma
theorem toReal_le_add (hle : a ≤ b + c) (hb : b ≠ ∞) (hc : c ≠ ∞) :
a.toReal ≤ b.toReal + c.toReal :=
toReal_le_add' hle (flip absurd hb) (flip absurd hc)
@[simp]
theorem toNNReal_le_toNNReal (ha : a ≠ ∞) (hb : b ≠ ∞) : a.toNNReal ≤ b.toNNReal ↔ a ≤ b :=
⟨fun h => by rwa [← coe_toNNReal ha, ← coe_toNNReal hb, coe_le_coe], toNNReal_mono hb⟩
#align ennreal.to_nnreal_le_to_nnreal ENNReal.toNNReal_le_toNNReal
theorem toNNReal_strict_mono (hb : b ≠ ∞) (h : a < b) : a.toNNReal < b.toNNReal := by
simpa [← ENNReal.coe_lt_coe, hb, h.ne_top]
#align ennreal.to_nnreal_strict_mono ENNReal.toNNReal_strict_mono
@[simp]
theorem toNNReal_lt_toNNReal (ha : a ≠ ∞) (hb : b ≠ ∞) : a.toNNReal < b.toNNReal ↔ a < b :=
⟨fun h => by rwa [← coe_toNNReal ha, ← coe_toNNReal hb, coe_lt_coe], toNNReal_strict_mono hb⟩
#align ennreal.to_nnreal_lt_to_nnreal ENNReal.toNNReal_lt_toNNReal
theorem toReal_max (hr : a ≠ ∞) (hp : b ≠ ∞) :
ENNReal.toReal (max a b) = max (ENNReal.toReal a) (ENNReal.toReal b) :=
(le_total a b).elim
(fun h => by simp only [h, (ENNReal.toReal_le_toReal hr hp).2 h, max_eq_right]) fun h => by
simp only [h, (ENNReal.toReal_le_toReal hp hr).2 h, max_eq_left]
#align ennreal.to_real_max ENNReal.toReal_max
theorem toReal_min {a b : ℝ≥0∞} (hr : a ≠ ∞) (hp : b ≠ ∞) :
ENNReal.toReal (min a b) = min (ENNReal.toReal a) (ENNReal.toReal b) :=
(le_total a b).elim (fun h => by simp only [h, (ENNReal.toReal_le_toReal hr hp).2 h, min_eq_left])
fun h => by simp only [h, (ENNReal.toReal_le_toReal hp hr).2 h, min_eq_right]
#align ennreal.to_real_min ENNReal.toReal_min
theorem toReal_sup {a b : ℝ≥0∞} : a ≠ ∞ → b ≠ ∞ → (a ⊔ b).toReal = a.toReal ⊔ b.toReal :=
toReal_max
#align ennreal.to_real_sup ENNReal.toReal_sup
theorem toReal_inf {a b : ℝ≥0∞} : a ≠ ∞ → b ≠ ∞ → (a ⊓ b).toReal = a.toReal ⊓ b.toReal :=
toReal_min
#align ennreal.to_real_inf ENNReal.toReal_inf
theorem toNNReal_pos_iff : 0 < a.toNNReal ↔ 0 < a ∧ a < ∞ := by
induction a <;> simp
#align ennreal.to_nnreal_pos_iff ENNReal.toNNReal_pos_iff
theorem toNNReal_pos {a : ℝ≥0∞} (ha₀ : a ≠ 0) (ha_top : a ≠ ∞) : 0 < a.toNNReal :=
toNNReal_pos_iff.mpr ⟨bot_lt_iff_ne_bot.mpr ha₀, lt_top_iff_ne_top.mpr ha_top⟩
#align ennreal.to_nnreal_pos ENNReal.toNNReal_pos
theorem toReal_pos_iff : 0 < a.toReal ↔ 0 < a ∧ a < ∞ :=
NNReal.coe_pos.trans toNNReal_pos_iff
#align ennreal.to_real_pos_iff ENNReal.toReal_pos_iff
theorem toReal_pos {a : ℝ≥0∞} (ha₀ : a ≠ 0) (ha_top : a ≠ ∞) : 0 < a.toReal :=
toReal_pos_iff.mpr ⟨bot_lt_iff_ne_bot.mpr ha₀, lt_top_iff_ne_top.mpr ha_top⟩
#align ennreal.to_real_pos ENNReal.toReal_pos
@[gcongr]
theorem ofReal_le_ofReal {p q : ℝ} (h : p ≤ q) : ENNReal.ofReal p ≤ ENNReal.ofReal q := by
simp [ENNReal.ofReal, Real.toNNReal_le_toNNReal h]
#align ennreal.of_real_le_of_real ENNReal.ofReal_le_ofReal
theorem ofReal_le_of_le_toReal {a : ℝ} {b : ℝ≥0∞} (h : a ≤ ENNReal.toReal b) :
ENNReal.ofReal a ≤ b :=
(ofReal_le_ofReal h).trans ofReal_toReal_le
#align ennreal.of_real_le_of_le_to_real ENNReal.ofReal_le_of_le_toReal
@[simp]
| Mathlib/Data/ENNReal/Real.lean | 189 | 191 | theorem ofReal_le_ofReal_iff {p q : ℝ} (h : 0 ≤ q) :
ENNReal.ofReal p ≤ ENNReal.ofReal q ↔ p ≤ q := by |
rw [ENNReal.ofReal, ENNReal.ofReal, coe_le_coe, Real.toNNReal_le_toNNReal_iff h]
|
import Mathlib.LinearAlgebra.Matrix.Symmetric
import Mathlib.LinearAlgebra.Matrix.Orthogonal
import Mathlib.Data.Matrix.Kronecker
#align_import linear_algebra.matrix.is_diag from "leanprover-community/mathlib"@"55e2dfde0cff928ce5c70926a3f2c7dee3e2dd99"
namespace Matrix
variable {α β R n m : Type*}
open Function
open Matrix Kronecker
def IsDiag [Zero α] (A : Matrix n n α) : Prop :=
Pairwise fun i j => A i j = 0
#align matrix.is_diag Matrix.IsDiag
@[simp]
theorem isDiag_diagonal [Zero α] [DecidableEq n] (d : n → α) : (diagonal d).IsDiag := fun _ _ =>
Matrix.diagonal_apply_ne _
#align matrix.is_diag_diagonal Matrix.isDiag_diagonal
theorem IsDiag.diagonal_diag [Zero α] [DecidableEq n] {A : Matrix n n α} (h : A.IsDiag) :
diagonal (diag A) = A :=
ext fun i j => by
obtain rfl | hij := Decidable.eq_or_ne i j
· rw [diagonal_apply_eq, diag]
· rw [diagonal_apply_ne _ hij, h hij]
#align matrix.is_diag.diagonal_diag Matrix.IsDiag.diagonal_diag
theorem isDiag_iff_diagonal_diag [Zero α] [DecidableEq n] (A : Matrix n n α) :
A.IsDiag ↔ diagonal (diag A) = A :=
⟨IsDiag.diagonal_diag, fun hd => hd ▸ isDiag_diagonal (diag A)⟩
#align matrix.is_diag_iff_diagonal_diag Matrix.isDiag_iff_diagonal_diag
theorem isDiag_of_subsingleton [Zero α] [Subsingleton n] (A : Matrix n n α) : A.IsDiag :=
fun i j h => (h <| Subsingleton.elim i j).elim
#align matrix.is_diag_of_subsingleton Matrix.isDiag_of_subsingleton
@[simp]
theorem isDiag_zero [Zero α] : (0 : Matrix n n α).IsDiag := fun _ _ _ => rfl
#align matrix.is_diag_zero Matrix.isDiag_zero
@[simp]
theorem isDiag_one [DecidableEq n] [Zero α] [One α] : (1 : Matrix n n α).IsDiag := fun _ _ =>
one_apply_ne
#align matrix.is_diag_one Matrix.isDiag_one
theorem IsDiag.map [Zero α] [Zero β] {A : Matrix n n α} (ha : A.IsDiag) {f : α → β} (hf : f 0 = 0) :
(A.map f).IsDiag := by
intro i j h
simp [ha h, hf]
#align matrix.is_diag.map Matrix.IsDiag.map
theorem IsDiag.neg [AddGroup α] {A : Matrix n n α} (ha : A.IsDiag) : (-A).IsDiag := by
intro i j h
simp [ha h]
#align matrix.is_diag.neg Matrix.IsDiag.neg
@[simp]
theorem isDiag_neg_iff [AddGroup α] {A : Matrix n n α} : (-A).IsDiag ↔ A.IsDiag :=
⟨fun ha _ _ h => neg_eq_zero.1 (ha h), IsDiag.neg⟩
#align matrix.is_diag_neg_iff Matrix.isDiag_neg_iff
| Mathlib/LinearAlgebra/Matrix/IsDiag.lean | 92 | 95 | theorem IsDiag.add [AddZeroClass α] {A B : Matrix n n α} (ha : A.IsDiag) (hb : B.IsDiag) :
(A + B).IsDiag := by |
intro i j h
simp [ha h, hb h]
|
import Mathlib.Algebra.Group.Prod
import Mathlib.Data.Set.Lattice
#align_import data.nat.pairing from "leanprover-community/mathlib"@"207cfac9fcd06138865b5d04f7091e46d9320432"
assert_not_exists MonoidWithZero
open Prod Decidable Function
namespace Nat
-- Porting note: no pp_nodot
--@[pp_nodot]
def pair (a b : ℕ) : ℕ :=
if a < b then b * b + a else a * a + a + b
#align nat.mkpair Nat.pair
-- Porting note: no pp_nodot
--@[pp_nodot]
def unpair (n : ℕ) : ℕ × ℕ :=
let s := sqrt n
if n - s * s < s then (n - s * s, s) else (s, n - s * s - s)
#align nat.unpair Nat.unpair
@[simp]
theorem pair_unpair (n : ℕ) : pair (unpair n).1 (unpair n).2 = n := by
dsimp only [unpair]; let s := sqrt n
have sm : s * s + (n - s * s) = n := Nat.add_sub_cancel' (sqrt_le _)
split_ifs with h
· simp [pair, h, sm]
· have hl : n - s * s - s ≤ s := Nat.sub_le_iff_le_add.2
(Nat.sub_le_iff_le_add'.2 <| by rw [← Nat.add_assoc]; apply sqrt_le_add)
simp [pair, hl.not_lt, Nat.add_assoc, Nat.add_sub_cancel' (le_of_not_gt h), sm]
#align nat.mkpair_unpair Nat.pair_unpair
| Mathlib/Data/Nat/Pairing.lean | 59 | 60 | theorem pair_unpair' {n a b} (H : unpair n = (a, b)) : pair a b = n := by |
simpa [H] using pair_unpair n
|
import Mathlib.Algebra.Order.Ring.Int
import Mathlib.Algebra.Ring.Rat
#align_import data.rat.order from "leanprover-community/mathlib"@"a59dad53320b73ef180174aae867addd707ef00e"
assert_not_exists Field
assert_not_exists Finset
assert_not_exists Set.Icc
assert_not_exists GaloisConnection
namespace Rat
variable {a b c p q : ℚ}
@[simp] lemma divInt_nonneg_iff_of_pos_right {a b : ℤ} (hb : 0 < b) : 0 ≤ a /. b ↔ 0 ≤ a := by
cases' hab : a /. b with n d hd hnd
rw [mk'_eq_divInt, divInt_eq_iff hb.ne' (mod_cast hd)] at hab
rw [← num_nonneg, ← mul_nonneg_iff_of_pos_right hb, ← hab,
mul_nonneg_iff_of_pos_right (mod_cast Nat.pos_of_ne_zero hd)]
#align rat.mk_nonneg Rat.divInt_nonneg_iff_of_pos_right
@[simp] lemma divInt_nonneg {a b : ℤ} (ha : 0 ≤ a) (hb : 0 ≤ b) : 0 ≤ a /. b := by
obtain rfl | hb := hb.eq_or_lt
· simp
rfl
rwa [divInt_nonneg_iff_of_pos_right hb]
@[simp] lemma mkRat_nonneg {a : ℤ} (ha : 0 ≤ a) (b : ℕ) : 0 ≤ mkRat a b := by
simpa using divInt_nonneg ha (Int.natCast_nonneg _)
theorem ofScientific_nonneg (m : ℕ) (s : Bool) (e : ℕ) :
0 ≤ Rat.ofScientific m s e := by
rw [Rat.ofScientific]
cases s
· rw [if_neg (by decide)]
refine num_nonneg.mp ?_
rw [num_natCast]
exact Int.natCast_nonneg _
· rw [if_pos rfl, normalize_eq_mkRat]
exact Rat.mkRat_nonneg (Int.natCast_nonneg _) _
instance _root_.NNRatCast.toOfScientific {K} [NNRatCast K] : OfScientific K where
ofScientific (m : ℕ) (b : Bool) (d : ℕ) :=
NNRat.cast ⟨Rat.ofScientific m b d, ofScientific_nonneg m b d⟩
@[simp, norm_cast]
theorem _root_.NNRat.cast_ofScientific {K} [NNRatCast K] (m : ℕ) (s : Bool) (e : ℕ) :
(OfScientific.ofScientific m s e : ℚ≥0) = (OfScientific.ofScientific m s e : K) :=
rfl
protected lemma add_nonneg : 0 ≤ a → 0 ≤ b → 0 ≤ a + b :=
numDenCasesOn' a fun n₁ d₁ h₁ ↦ numDenCasesOn' b fun n₂ d₂ h₂ ↦ by
have d₁0 : 0 < (d₁ : ℤ) := mod_cast Nat.pos_of_ne_zero h₁
have d₂0 : 0 < (d₂ : ℤ) := mod_cast Nat.pos_of_ne_zero h₂
simp only [d₁0, d₂0, h₁, h₂, mul_pos, divInt_nonneg_iff_of_pos_right, divInt_add_divInt, Ne,
Nat.cast_eq_zero, not_false_iff]
intro n₁0 n₂0
apply add_nonneg <;> apply mul_nonneg <;> · first |assumption|apply Int.ofNat_zero_le
#align rat.nonneg_add Rat.add_nonneg
protected lemma mul_nonneg : 0 ≤ a → 0 ≤ b → 0 ≤ a * b :=
numDenCasesOn' a fun n₁ d₁ h₁ =>
numDenCasesOn' b fun n₂ d₂ h₂ => by
have d₁0 : 0 < (d₁ : ℤ) := mod_cast Nat.pos_of_ne_zero h₁
have d₂0 : 0 < (d₂ : ℤ) := mod_cast Nat.pos_of_ne_zero h₂
simp only [d₁0, d₂0, mul_pos, divInt_nonneg_iff_of_pos_right,
divInt_mul_divInt _ _ d₁0.ne' d₂0.ne']
apply mul_nonneg
#align rat.nonneg_mul Rat.mul_nonneg
#align rat.mul_nonneg Rat.mul_nonneg
-- Porting note (#11215): TODO can this be shortened?
protected theorem le_iff_sub_nonneg (a b : ℚ) : a ≤ b ↔ 0 ≤ b - a :=
numDenCasesOn'' a fun na da ha hared =>
numDenCasesOn'' b fun nb db hb hbred => by
change Rat.blt _ _ = false ↔ _
unfold Rat.blt
simp only [Bool.and_eq_true, decide_eq_true_eq, Bool.ite_eq_false_distrib,
decide_eq_false_iff_not, not_lt, ite_eq_left_iff, not_and, not_le, ← num_nonneg]
split_ifs with h h'
· rw [Rat.sub_def]
simp only [false_iff, not_le]
simp only [normalize_eq]
apply Int.ediv_neg'
· rw [sub_neg]
apply lt_of_lt_of_le
· apply mul_neg_of_neg_of_pos h.1
rwa [Int.natCast_pos, Nat.pos_iff_ne_zero]
· apply mul_nonneg h.2 (Int.natCast_nonneg _)
· simp only [Int.natCast_pos, Nat.pos_iff_ne_zero]
exact Nat.gcd_ne_zero_right (Nat.mul_ne_zero hb ha)
· simp only [divInt_ofNat, ← zero_iff_num_zero, mkRat_eq_zero hb] at h'
simp [h']
· simp only [Rat.sub_def, normalize_eq]
refine ⟨fun H => ?_, fun H _ => ?_⟩
· refine Int.ediv_nonneg ?_ (Int.natCast_nonneg _)
rw [sub_nonneg]
push_neg at h
obtain hb|hb := Ne.lt_or_lt h'
· apply H
intro H'
exact (hb.trans H').false.elim
· obtain ha|ha := le_or_lt na 0
· apply le_trans <| mul_nonpos_of_nonpos_of_nonneg ha (Int.natCast_nonneg _)
exact mul_nonneg hb.le (Int.natCast_nonneg _)
· exact H (fun _ => ha)
· rw [← sub_nonneg]
contrapose! H
apply Int.ediv_neg' H
simp only [Int.natCast_pos, Nat.pos_iff_ne_zero]
exact Nat.gcd_ne_zero_right (Nat.mul_ne_zero hb ha)
protected lemma divInt_le_divInt {a b c d : ℤ} (b0 : 0 < b) (d0 : 0 < d) :
a /. b ≤ c /. d ↔ a * d ≤ c * b := by
rw [Rat.le_iff_sub_nonneg, ← sub_nonneg (α := ℤ)]
simp [sub_eq_add_neg, ne_of_gt b0, ne_of_gt d0, mul_pos d0 b0]
#align rat.le_def Rat.divInt_le_divInt
protected lemma le_total : a ≤ b ∨ b ≤ a := by
simpa only [← Rat.le_iff_sub_nonneg, neg_sub] using Rat.nonneg_total (b - a)
#align rat.le_total Rat.le_total
protected theorem not_le {a b : ℚ} : ¬a ≤ b ↔ b < a := (Bool.not_eq_false _).to_iff
instance linearOrder : LinearOrder ℚ where
le_refl a := by rw [Rat.le_iff_sub_nonneg, ← num_nonneg]; simp
le_trans a b c hab hbc := by
rw [Rat.le_iff_sub_nonneg] at hab hbc
have := Rat.add_nonneg hab hbc
simp_rw [sub_eq_add_neg, add_left_comm (b + -a) c (-b), add_comm (b + -a) (-b),
add_left_comm (-b) b (-a), add_comm (-b) (-a), add_neg_cancel_comm_assoc,
← sub_eq_add_neg] at this
rwa [Rat.le_iff_sub_nonneg]
le_antisymm a b hab hba := by
rw [Rat.le_iff_sub_nonneg] at hab hba
rw [sub_eq_add_neg] at hba
rw [← neg_sub, sub_eq_add_neg] at hab
have := eq_neg_of_add_eq_zero_left (Rat.nonneg_antisymm hba hab)
rwa [neg_neg] at this
le_total _ _ := Rat.le_total
decidableEq := inferInstance
decidableLE := inferInstance
decidableLT := inferInstance
lt_iff_le_not_le _ _ := by rw [← Rat.not_le, and_iff_right_of_imp Rat.le_total.resolve_left]
#align rat.le_refl le_refl
#align rat.le_antisymm le_antisymm
#align rat.le_trans le_trans
instance instDistribLattice : DistribLattice ℚ := inferInstance
instance instLattice : Lattice ℚ := inferInstance
instance instSemilatticeInf : SemilatticeInf ℚ := inferInstance
instance instSemilatticeSup : SemilatticeSup ℚ := inferInstance
instance instInf : Inf ℚ := inferInstance
instance instSup : Sup ℚ := inferInstance
instance instPartialOrder : PartialOrder ℚ := inferInstance
instance instPreorder : Preorder ℚ := inferInstance
protected lemma le_def : p ≤ q ↔ p.num * q.den ≤ q.num * p.den := by
rw [← num_divInt_den q, ← num_divInt_den p]
conv_rhs => simp only [num_divInt_den]
exact Rat.divInt_le_divInt (mod_cast p.pos) (mod_cast q.pos)
#align rat.le_def' Rat.le_def
protected lemma lt_def : p < q ↔ p.num * q.den < q.num * p.den := by
rw [lt_iff_le_and_ne, Rat.le_def]
suffices p ≠ q ↔ p.num * q.den ≠ q.num * p.den by
constructor <;> intro h
· exact lt_iff_le_and_ne.mpr ⟨h.left, this.mp h.right⟩
· have tmp := lt_iff_le_and_ne.mp h
exact ⟨tmp.left, this.mpr tmp.right⟩
exact not_iff_not.mpr eq_iff_mul_eq_mul
#align rat.lt_def Rat.lt_def
#noalign rat.nonneg_iff_zero_le
protected theorem add_le_add_left {a b c : ℚ} : c + a ≤ c + b ↔ a ≤ b := by
rw [Rat.le_iff_sub_nonneg, add_sub_add_left_eq_sub, ← Rat.le_iff_sub_nonneg]
#align rat.add_le_add_left Rat.add_le_add_left
instance instLinearOrderedCommRing : LinearOrderedCommRing ℚ where
__ := Rat.linearOrder
__ := Rat.commRing
zero_le_one := by decide
add_le_add_left := fun a b ab c => Rat.add_le_add_left.2 ab
mul_pos a b ha hb := (Rat.mul_nonneg ha.le hb.le).lt_of_ne' (mul_ne_zero ha.ne' hb.ne')
-- Extra instances to short-circuit type class resolution
instance : LinearOrderedRing ℚ := by infer_instance
instance : OrderedRing ℚ := by infer_instance
instance : LinearOrderedSemiring ℚ := by infer_instance
instance : OrderedSemiring ℚ := by infer_instance
instance : LinearOrderedAddCommGroup ℚ := by infer_instance
instance : OrderedAddCommGroup ℚ := by infer_instance
instance : OrderedCancelAddCommMonoid ℚ := by infer_instance
instance : OrderedAddCommMonoid ℚ := by infer_instance
@[simp] lemma num_nonpos {a : ℚ} : a.num ≤ 0 ↔ a ≤ 0 := by simpa using @num_nonneg (-a)
@[simp] lemma num_pos {a : ℚ} : 0 < a.num ↔ 0 < a := lt_iff_lt_of_le_iff_le num_nonpos
#align rat.num_pos_iff_pos Rat.num_pos
@[simp] lemma num_neg {a : ℚ} : a.num < 0 ↔ a < 0 := lt_iff_lt_of_le_iff_le num_nonneg
@[deprecated (since := "2024-02-16")] alias num_nonneg_iff_zero_le := num_nonneg
@[deprecated (since := "2024-02-16")] alias num_pos_iff_pos := num_pos
theorem div_lt_div_iff_mul_lt_mul {a b c d : ℤ} (b_pos : 0 < b) (d_pos : 0 < d) :
(a : ℚ) / b < c / d ↔ a * d < c * b := by
simp only [lt_iff_le_not_le]
apply and_congr
· simp [div_def', Rat.divInt_le_divInt b_pos d_pos]
· apply not_congr
simp [div_def', Rat.divInt_le_divInt d_pos b_pos]
#align rat.div_lt_div_iff_mul_lt_mul Rat.div_lt_div_iff_mul_lt_mul
| Mathlib/Algebra/Order/Ring/Rat.lean | 249 | 249 | theorem lt_one_iff_num_lt_denom {q : ℚ} : q < 1 ↔ q.num < q.den := by | simp [Rat.lt_def]
|
import Mathlib.Algebra.GroupWithZero.Hom
import Mathlib.Algebra.GroupWithZero.Units.Basic
import Mathlib.Algebra.Ring.Defs
import Mathlib.Data.Nat.Lattice
#align_import ring_theory.nilpotent from "leanprover-community/mathlib"@"da420a8c6dd5bdfb85c4ced85c34388f633bc6ff"
universe u v
open Function Set
variable {R S : Type*} {x y : R}
def IsNilpotent [Zero R] [Pow R ℕ] (x : R) : Prop :=
∃ n : ℕ, x ^ n = 0
#align is_nilpotent IsNilpotent
theorem IsNilpotent.mk [Zero R] [Pow R ℕ] (x : R) (n : ℕ) (e : x ^ n = 0) : IsNilpotent x :=
⟨n, e⟩
#align is_nilpotent.mk IsNilpotent.mk
@[simp] lemma isNilpotent_of_subsingleton [Zero R] [Pow R ℕ] [Subsingleton R] : IsNilpotent x :=
⟨0, Subsingleton.elim _ _⟩
@[simp] theorem IsNilpotent.zero [MonoidWithZero R] : IsNilpotent (0 : R) :=
⟨1, pow_one 0⟩
#align is_nilpotent.zero IsNilpotent.zero
theorem not_isNilpotent_one [MonoidWithZero R] [Nontrivial R] :
¬ IsNilpotent (1 : R) := fun ⟨_, H⟩ ↦ zero_ne_one (H.symm.trans (one_pow _))
lemma IsNilpotent.pow_succ (n : ℕ) {S : Type*} [MonoidWithZero S] {x : S}
(hx : IsNilpotent x) : IsNilpotent (x ^ n.succ) := by
obtain ⟨N,hN⟩ := hx
use N
rw [← pow_mul, Nat.succ_mul, pow_add, hN, mul_zero]
theorem IsNilpotent.of_pow [MonoidWithZero R] {x : R} {m : ℕ}
(h : IsNilpotent (x ^ m)) : IsNilpotent x := by
obtain ⟨n, h⟩ := h
use m*n
rw [← h, pow_mul x m n]
lemma IsNilpotent.pow_of_pos {n} {S : Type*} [MonoidWithZero S] {x : S}
(hx : IsNilpotent x) (hn : n ≠ 0) : IsNilpotent (x ^ n) := by
cases n with
| zero => contradiction
| succ => exact IsNilpotent.pow_succ _ hx
@[simp]
lemma IsNilpotent.pow_iff_pos {n} {S : Type*} [MonoidWithZero S] {x : S}
(hn : n ≠ 0) : IsNilpotent (x ^ n) ↔ IsNilpotent x :=
⟨fun h => of_pow h, fun h => pow_of_pos h hn⟩
theorem IsNilpotent.map [MonoidWithZero R] [MonoidWithZero S] {r : R} {F : Type*}
[FunLike F R S] [MonoidWithZeroHomClass F R S] (hr : IsNilpotent r) (f : F) :
IsNilpotent (f r) := by
use hr.choose
rw [← map_pow, hr.choose_spec, map_zero]
#align is_nilpotent.map IsNilpotent.map
lemma IsNilpotent.map_iff [MonoidWithZero R] [MonoidWithZero S] {r : R} {F : Type*}
[FunLike F R S] [MonoidWithZeroHomClass F R S] {f : F} (hf : Function.Injective f) :
IsNilpotent (f r) ↔ IsNilpotent r :=
⟨fun ⟨k, hk⟩ ↦ ⟨k, (map_eq_zero_iff f hf).mp <| by rwa [map_pow]⟩, fun h ↦ h.map f⟩
theorem IsUnit.isNilpotent_mul_unit_of_commute_iff [MonoidWithZero R] {r u : R}
(hu : IsUnit u) (h_comm : Commute r u) :
IsNilpotent (r * u) ↔ IsNilpotent r :=
exists_congr fun n ↦ by rw [h_comm.mul_pow, (hu.pow n).mul_left_eq_zero]
theorem IsUnit.isNilpotent_unit_mul_of_commute_iff [MonoidWithZero R] {r u : R}
(hu : IsUnit u) (h_comm : Commute r u) :
IsNilpotent (u * r) ↔ IsNilpotent r :=
h_comm ▸ hu.isNilpotent_mul_unit_of_commute_iff h_comm
section NilpotencyClass
@[mk_iff]
class IsReduced (R : Type*) [Zero R] [Pow R ℕ] : Prop where
eq_zero : ∀ x : R, IsNilpotent x → x = 0
#align is_reduced IsReduced
instance (priority := 900) isReduced_of_noZeroDivisors [MonoidWithZero R] [NoZeroDivisors R] :
IsReduced R :=
⟨fun _ ⟨_, hn⟩ => pow_eq_zero hn⟩
#align is_reduced_of_no_zero_divisors isReduced_of_noZeroDivisors
instance (priority := 900) isReduced_of_subsingleton [Zero R] [Pow R ℕ] [Subsingleton R] :
IsReduced R :=
⟨fun _ _ => Subsingleton.elim _ _⟩
#align is_reduced_of_subsingleton isReduced_of_subsingleton
theorem IsNilpotent.eq_zero [Zero R] [Pow R ℕ] [IsReduced R] (h : IsNilpotent x) : x = 0 :=
IsReduced.eq_zero x h
#align is_nilpotent.eq_zero IsNilpotent.eq_zero
@[simp]
theorem isNilpotent_iff_eq_zero [MonoidWithZero R] [IsReduced R] : IsNilpotent x ↔ x = 0 :=
⟨fun h => h.eq_zero, fun h => h.symm ▸ IsNilpotent.zero⟩
#align is_nilpotent_iff_eq_zero isNilpotent_iff_eq_zero
theorem isReduced_of_injective [MonoidWithZero R] [MonoidWithZero S] {F : Type*}
[FunLike F R S] [MonoidWithZeroHomClass F R S]
(f : F) (hf : Function.Injective f) [IsReduced S] :
IsReduced R := by
constructor
intro x hx
apply hf
rw [map_zero]
exact (hx.map f).eq_zero
#align is_reduced_of_injective isReduced_of_injective
instance (ι) (R : ι → Type*) [∀ i, Zero (R i)] [∀ i, Pow (R i) ℕ]
[∀ i, IsReduced (R i)] : IsReduced (∀ i, R i) where
eq_zero _ := fun ⟨n, hn⟩ ↦ funext fun i ↦ IsReduced.eq_zero _ ⟨n, congr_fun hn i⟩
def IsRadical [Dvd R] [Pow R ℕ] (y : R) : Prop :=
∀ (n : ℕ) (x), y ∣ x ^ n → y ∣ x
#align is_radical IsRadical
theorem isRadical_iff_pow_one_lt [MonoidWithZero R] (k : ℕ) (hk : 1 < k) :
IsRadical y ↔ ∀ x, y ∣ x ^ k → y ∣ x :=
⟨(· k), k.pow_imp_self_of_one_lt hk _ fun _ _ h ↦ .inl (dvd_mul_of_dvd_left h _)⟩
#align is_radical_iff_pow_one_lt isRadical_iff_pow_one_lt
namespace Commute
section Semiring
variable [Semiring R] (h_comm : Commute x y)
theorem isNilpotent_mul_left (h : IsNilpotent x) : IsNilpotent (x * y) := by
obtain ⟨n, hn⟩ := h
use n
rw [h_comm.mul_pow, hn, zero_mul]
#align commute.is_nilpotent_mul_left Commute.isNilpotent_mul_left
| Mathlib/RingTheory/Nilpotent/Defs.lean | 235 | 237 | theorem isNilpotent_mul_right (h : IsNilpotent y) : IsNilpotent (x * y) := by |
rw [h_comm.eq]
exact h_comm.symm.isNilpotent_mul_left h
|
import Mathlib.Analysis.InnerProductSpace.TwoDim
import Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic
#align_import geometry.euclidean.angle.oriented.basic from "leanprover-community/mathlib"@"f0c8bf9245297a541f468be517f1bde6195105e9"
noncomputable section
open FiniteDimensional Complex
open scoped Real RealInnerProductSpace ComplexConjugate
namespace Orientation
attribute [local instance] Complex.finrank_real_complex_fact
variable {V V' : Type*}
variable [NormedAddCommGroup V] [NormedAddCommGroup V']
variable [InnerProductSpace ℝ V] [InnerProductSpace ℝ V']
variable [Fact (finrank ℝ V = 2)] [Fact (finrank ℝ V' = 2)] (o : Orientation ℝ V (Fin 2))
local notation "ω" => o.areaForm
def oangle (x y : V) : Real.Angle :=
Complex.arg (o.kahler x y)
#align orientation.oangle Orientation.oangle
theorem continuousAt_oangle {x : V × V} (hx1 : x.1 ≠ 0) (hx2 : x.2 ≠ 0) :
ContinuousAt (fun y : V × V => o.oangle y.1 y.2) x := by
refine (Complex.continuousAt_arg_coe_angle ?_).comp ?_
· exact o.kahler_ne_zero hx1 hx2
exact ((continuous_ofReal.comp continuous_inner).add
((continuous_ofReal.comp o.areaForm'.continuous₂).mul continuous_const)).continuousAt
#align orientation.continuous_at_oangle Orientation.continuousAt_oangle
@[simp]
theorem oangle_zero_left (x : V) : o.oangle 0 x = 0 := by simp [oangle]
#align orientation.oangle_zero_left Orientation.oangle_zero_left
@[simp]
theorem oangle_zero_right (x : V) : o.oangle x 0 = 0 := by simp [oangle]
#align orientation.oangle_zero_right Orientation.oangle_zero_right
@[simp]
theorem oangle_self (x : V) : o.oangle x x = 0 := by
rw [oangle, kahler_apply_self, ← ofReal_pow]
convert QuotientAddGroup.mk_zero (AddSubgroup.zmultiples (2 * π))
apply arg_ofReal_of_nonneg
positivity
#align orientation.oangle_self Orientation.oangle_self
theorem left_ne_zero_of_oangle_ne_zero {x y : V} (h : o.oangle x y ≠ 0) : x ≠ 0 := by
rintro rfl; simp at h
#align orientation.left_ne_zero_of_oangle_ne_zero Orientation.left_ne_zero_of_oangle_ne_zero
theorem right_ne_zero_of_oangle_ne_zero {x y : V} (h : o.oangle x y ≠ 0) : y ≠ 0 := by
rintro rfl; simp at h
#align orientation.right_ne_zero_of_oangle_ne_zero Orientation.right_ne_zero_of_oangle_ne_zero
theorem ne_of_oangle_ne_zero {x y : V} (h : o.oangle x y ≠ 0) : x ≠ y := by
rintro rfl; simp at h
#align orientation.ne_of_oangle_ne_zero Orientation.ne_of_oangle_ne_zero
theorem left_ne_zero_of_oangle_eq_pi {x y : V} (h : o.oangle x y = π) : x ≠ 0 :=
o.left_ne_zero_of_oangle_ne_zero (h.symm ▸ Real.Angle.pi_ne_zero : o.oangle x y ≠ 0)
#align orientation.left_ne_zero_of_oangle_eq_pi Orientation.left_ne_zero_of_oangle_eq_pi
theorem right_ne_zero_of_oangle_eq_pi {x y : V} (h : o.oangle x y = π) : y ≠ 0 :=
o.right_ne_zero_of_oangle_ne_zero (h.symm ▸ Real.Angle.pi_ne_zero : o.oangle x y ≠ 0)
#align orientation.right_ne_zero_of_oangle_eq_pi Orientation.right_ne_zero_of_oangle_eq_pi
theorem ne_of_oangle_eq_pi {x y : V} (h : o.oangle x y = π) : x ≠ y :=
o.ne_of_oangle_ne_zero (h.symm ▸ Real.Angle.pi_ne_zero : o.oangle x y ≠ 0)
#align orientation.ne_of_oangle_eq_pi Orientation.ne_of_oangle_eq_pi
theorem left_ne_zero_of_oangle_eq_pi_div_two {x y : V} (h : o.oangle x y = (π / 2 : ℝ)) : x ≠ 0 :=
o.left_ne_zero_of_oangle_ne_zero (h.symm ▸ Real.Angle.pi_div_two_ne_zero : o.oangle x y ≠ 0)
#align orientation.left_ne_zero_of_oangle_eq_pi_div_two Orientation.left_ne_zero_of_oangle_eq_pi_div_two
theorem right_ne_zero_of_oangle_eq_pi_div_two {x y : V} (h : o.oangle x y = (π / 2 : ℝ)) : y ≠ 0 :=
o.right_ne_zero_of_oangle_ne_zero (h.symm ▸ Real.Angle.pi_div_two_ne_zero : o.oangle x y ≠ 0)
#align orientation.right_ne_zero_of_oangle_eq_pi_div_two Orientation.right_ne_zero_of_oangle_eq_pi_div_two
theorem ne_of_oangle_eq_pi_div_two {x y : V} (h : o.oangle x y = (π / 2 : ℝ)) : x ≠ y :=
o.ne_of_oangle_ne_zero (h.symm ▸ Real.Angle.pi_div_two_ne_zero : o.oangle x y ≠ 0)
#align orientation.ne_of_oangle_eq_pi_div_two Orientation.ne_of_oangle_eq_pi_div_two
theorem left_ne_zero_of_oangle_eq_neg_pi_div_two {x y : V} (h : o.oangle x y = (-π / 2 : ℝ)) :
x ≠ 0 :=
o.left_ne_zero_of_oangle_ne_zero (h.symm ▸ Real.Angle.neg_pi_div_two_ne_zero : o.oangle x y ≠ 0)
#align orientation.left_ne_zero_of_oangle_eq_neg_pi_div_two Orientation.left_ne_zero_of_oangle_eq_neg_pi_div_two
theorem right_ne_zero_of_oangle_eq_neg_pi_div_two {x y : V} (h : o.oangle x y = (-π / 2 : ℝ)) :
y ≠ 0 :=
o.right_ne_zero_of_oangle_ne_zero (h.symm ▸ Real.Angle.neg_pi_div_two_ne_zero : o.oangle x y ≠ 0)
#align orientation.right_ne_zero_of_oangle_eq_neg_pi_div_two Orientation.right_ne_zero_of_oangle_eq_neg_pi_div_two
theorem ne_of_oangle_eq_neg_pi_div_two {x y : V} (h : o.oangle x y = (-π / 2 : ℝ)) : x ≠ y :=
o.ne_of_oangle_ne_zero (h.symm ▸ Real.Angle.neg_pi_div_two_ne_zero : o.oangle x y ≠ 0)
#align orientation.ne_of_oangle_eq_neg_pi_div_two Orientation.ne_of_oangle_eq_neg_pi_div_two
theorem left_ne_zero_of_oangle_sign_ne_zero {x y : V} (h : (o.oangle x y).sign ≠ 0) : x ≠ 0 :=
o.left_ne_zero_of_oangle_ne_zero (Real.Angle.sign_ne_zero_iff.1 h).1
#align orientation.left_ne_zero_of_oangle_sign_ne_zero Orientation.left_ne_zero_of_oangle_sign_ne_zero
theorem right_ne_zero_of_oangle_sign_ne_zero {x y : V} (h : (o.oangle x y).sign ≠ 0) : y ≠ 0 :=
o.right_ne_zero_of_oangle_ne_zero (Real.Angle.sign_ne_zero_iff.1 h).1
#align orientation.right_ne_zero_of_oangle_sign_ne_zero Orientation.right_ne_zero_of_oangle_sign_ne_zero
theorem ne_of_oangle_sign_ne_zero {x y : V} (h : (o.oangle x y).sign ≠ 0) : x ≠ y :=
o.ne_of_oangle_ne_zero (Real.Angle.sign_ne_zero_iff.1 h).1
#align orientation.ne_of_oangle_sign_ne_zero Orientation.ne_of_oangle_sign_ne_zero
theorem left_ne_zero_of_oangle_sign_eq_one {x y : V} (h : (o.oangle x y).sign = 1) : x ≠ 0 :=
o.left_ne_zero_of_oangle_sign_ne_zero (h.symm ▸ by decide : (o.oangle x y).sign ≠ 0)
#align orientation.left_ne_zero_of_oangle_sign_eq_one Orientation.left_ne_zero_of_oangle_sign_eq_one
theorem right_ne_zero_of_oangle_sign_eq_one {x y : V} (h : (o.oangle x y).sign = 1) : y ≠ 0 :=
o.right_ne_zero_of_oangle_sign_ne_zero (h.symm ▸ by decide : (o.oangle x y).sign ≠ 0)
#align orientation.right_ne_zero_of_oangle_sign_eq_one Orientation.right_ne_zero_of_oangle_sign_eq_one
theorem ne_of_oangle_sign_eq_one {x y : V} (h : (o.oangle x y).sign = 1) : x ≠ y :=
o.ne_of_oangle_sign_ne_zero (h.symm ▸ by decide : (o.oangle x y).sign ≠ 0)
#align orientation.ne_of_oangle_sign_eq_one Orientation.ne_of_oangle_sign_eq_one
theorem left_ne_zero_of_oangle_sign_eq_neg_one {x y : V} (h : (o.oangle x y).sign = -1) : x ≠ 0 :=
o.left_ne_zero_of_oangle_sign_ne_zero (h.symm ▸ by decide : (o.oangle x y).sign ≠ 0)
#align orientation.left_ne_zero_of_oangle_sign_eq_neg_one Orientation.left_ne_zero_of_oangle_sign_eq_neg_one
theorem right_ne_zero_of_oangle_sign_eq_neg_one {x y : V} (h : (o.oangle x y).sign = -1) : y ≠ 0 :=
o.right_ne_zero_of_oangle_sign_ne_zero (h.symm ▸ by decide : (o.oangle x y).sign ≠ 0)
#align orientation.right_ne_zero_of_oangle_sign_eq_neg_one Orientation.right_ne_zero_of_oangle_sign_eq_neg_one
theorem ne_of_oangle_sign_eq_neg_one {x y : V} (h : (o.oangle x y).sign = -1) : x ≠ y :=
o.ne_of_oangle_sign_ne_zero (h.symm ▸ by decide : (o.oangle x y).sign ≠ 0)
#align orientation.ne_of_oangle_sign_eq_neg_one Orientation.ne_of_oangle_sign_eq_neg_one
theorem oangle_rev (x y : V) : o.oangle y x = -o.oangle x y := by
simp only [oangle, o.kahler_swap y x, Complex.arg_conj_coe_angle]
#align orientation.oangle_rev Orientation.oangle_rev
@[simp]
theorem oangle_add_oangle_rev (x y : V) : o.oangle x y + o.oangle y x = 0 := by
simp [o.oangle_rev y x]
#align orientation.oangle_add_oangle_rev Orientation.oangle_add_oangle_rev
theorem oangle_neg_left {x y : V} (hx : x ≠ 0) (hy : y ≠ 0) :
o.oangle (-x) y = o.oangle x y + π := by
simp only [oangle, map_neg]
convert Complex.arg_neg_coe_angle _
exact o.kahler_ne_zero hx hy
#align orientation.oangle_neg_left Orientation.oangle_neg_left
theorem oangle_neg_right {x y : V} (hx : x ≠ 0) (hy : y ≠ 0) :
o.oangle x (-y) = o.oangle x y + π := by
simp only [oangle, map_neg]
convert Complex.arg_neg_coe_angle _
exact o.kahler_ne_zero hx hy
#align orientation.oangle_neg_right Orientation.oangle_neg_right
@[simp]
theorem two_zsmul_oangle_neg_left (x y : V) :
(2 : ℤ) • o.oangle (-x) y = (2 : ℤ) • o.oangle x y := by
by_cases hx : x = 0
· simp [hx]
· by_cases hy : y = 0
· simp [hy]
· simp [o.oangle_neg_left hx hy]
#align orientation.two_zsmul_oangle_neg_left Orientation.two_zsmul_oangle_neg_left
@[simp]
theorem two_zsmul_oangle_neg_right (x y : V) :
(2 : ℤ) • o.oangle x (-y) = (2 : ℤ) • o.oangle x y := by
by_cases hx : x = 0
· simp [hx]
· by_cases hy : y = 0
· simp [hy]
· simp [o.oangle_neg_right hx hy]
#align orientation.two_zsmul_oangle_neg_right Orientation.two_zsmul_oangle_neg_right
@[simp]
theorem oangle_neg_neg (x y : V) : o.oangle (-x) (-y) = o.oangle x y := by simp [oangle]
#align orientation.oangle_neg_neg Orientation.oangle_neg_neg
theorem oangle_neg_left_eq_neg_right (x y : V) : o.oangle (-x) y = o.oangle x (-y) := by
rw [← neg_neg y, oangle_neg_neg, neg_neg]
#align orientation.oangle_neg_left_eq_neg_right Orientation.oangle_neg_left_eq_neg_right
@[simp]
theorem oangle_neg_self_left {x : V} (hx : x ≠ 0) : o.oangle (-x) x = π := by
simp [oangle_neg_left, hx]
#align orientation.oangle_neg_self_left Orientation.oangle_neg_self_left
@[simp]
theorem oangle_neg_self_right {x : V} (hx : x ≠ 0) : o.oangle x (-x) = π := by
simp [oangle_neg_right, hx]
#align orientation.oangle_neg_self_right Orientation.oangle_neg_self_right
-- @[simp] -- Porting note (#10618): simp can prove this
theorem two_zsmul_oangle_neg_self_left (x : V) : (2 : ℤ) • o.oangle (-x) x = 0 := by
by_cases hx : x = 0 <;> simp [hx]
#align orientation.two_zsmul_oangle_neg_self_left Orientation.two_zsmul_oangle_neg_self_left
-- @[simp] -- Porting note (#10618): simp can prove this
theorem two_zsmul_oangle_neg_self_right (x : V) : (2 : ℤ) • o.oangle x (-x) = 0 := by
by_cases hx : x = 0 <;> simp [hx]
#align orientation.two_zsmul_oangle_neg_self_right Orientation.two_zsmul_oangle_neg_self_right
@[simp]
theorem oangle_add_oangle_rev_neg_left (x y : V) : o.oangle (-x) y + o.oangle (-y) x = 0 := by
rw [oangle_neg_left_eq_neg_right, oangle_rev, add_left_neg]
#align orientation.oangle_add_oangle_rev_neg_left Orientation.oangle_add_oangle_rev_neg_left
@[simp]
theorem oangle_add_oangle_rev_neg_right (x y : V) : o.oangle x (-y) + o.oangle y (-x) = 0 := by
rw [o.oangle_rev (-x), oangle_neg_left_eq_neg_right, add_neg_self]
#align orientation.oangle_add_oangle_rev_neg_right Orientation.oangle_add_oangle_rev_neg_right
@[simp]
theorem oangle_smul_left_of_pos (x y : V) {r : ℝ} (hr : 0 < r) :
o.oangle (r • x) y = o.oangle x y := by simp [oangle, Complex.arg_real_mul _ hr]
#align orientation.oangle_smul_left_of_pos Orientation.oangle_smul_left_of_pos
@[simp]
theorem oangle_smul_right_of_pos (x y : V) {r : ℝ} (hr : 0 < r) :
o.oangle x (r • y) = o.oangle x y := by simp [oangle, Complex.arg_real_mul _ hr]
#align orientation.oangle_smul_right_of_pos Orientation.oangle_smul_right_of_pos
@[simp]
theorem oangle_smul_left_of_neg (x y : V) {r : ℝ} (hr : r < 0) :
o.oangle (r • x) y = o.oangle (-x) y := by
rw [← neg_neg r, neg_smul, ← smul_neg, o.oangle_smul_left_of_pos _ _ (neg_pos_of_neg hr)]
#align orientation.oangle_smul_left_of_neg Orientation.oangle_smul_left_of_neg
@[simp]
theorem oangle_smul_right_of_neg (x y : V) {r : ℝ} (hr : r < 0) :
o.oangle x (r • y) = o.oangle x (-y) := by
rw [← neg_neg r, neg_smul, ← smul_neg, o.oangle_smul_right_of_pos _ _ (neg_pos_of_neg hr)]
#align orientation.oangle_smul_right_of_neg Orientation.oangle_smul_right_of_neg
@[simp]
theorem oangle_smul_left_self_of_nonneg (x : V) {r : ℝ} (hr : 0 ≤ r) : o.oangle (r • x) x = 0 := by
rcases hr.lt_or_eq with (h | h)
· simp [h]
· simp [h.symm]
#align orientation.oangle_smul_left_self_of_nonneg Orientation.oangle_smul_left_self_of_nonneg
@[simp]
theorem oangle_smul_right_self_of_nonneg (x : V) {r : ℝ} (hr : 0 ≤ r) : o.oangle x (r • x) = 0 := by
rcases hr.lt_or_eq with (h | h)
· simp [h]
· simp [h.symm]
#align orientation.oangle_smul_right_self_of_nonneg Orientation.oangle_smul_right_self_of_nonneg
@[simp]
theorem oangle_smul_smul_self_of_nonneg (x : V) {r₁ r₂ : ℝ} (hr₁ : 0 ≤ r₁) (hr₂ : 0 ≤ r₂) :
o.oangle (r₁ • x) (r₂ • x) = 0 := by
rcases hr₁.lt_or_eq with (h | h)
· simp [h, hr₂]
· simp [h.symm]
#align orientation.oangle_smul_smul_self_of_nonneg Orientation.oangle_smul_smul_self_of_nonneg
@[simp]
theorem two_zsmul_oangle_smul_left_of_ne_zero (x y : V) {r : ℝ} (hr : r ≠ 0) :
(2 : ℤ) • o.oangle (r • x) y = (2 : ℤ) • o.oangle x y := by
rcases hr.lt_or_lt with (h | h) <;> simp [h]
#align orientation.two_zsmul_oangle_smul_left_of_ne_zero Orientation.two_zsmul_oangle_smul_left_of_ne_zero
@[simp]
theorem two_zsmul_oangle_smul_right_of_ne_zero (x y : V) {r : ℝ} (hr : r ≠ 0) :
(2 : ℤ) • o.oangle x (r • y) = (2 : ℤ) • o.oangle x y := by
rcases hr.lt_or_lt with (h | h) <;> simp [h]
#align orientation.two_zsmul_oangle_smul_right_of_ne_zero Orientation.two_zsmul_oangle_smul_right_of_ne_zero
@[simp]
theorem two_zsmul_oangle_smul_left_self (x : V) {r : ℝ} : (2 : ℤ) • o.oangle (r • x) x = 0 := by
rcases lt_or_le r 0 with (h | h) <;> simp [h]
#align orientation.two_zsmul_oangle_smul_left_self Orientation.two_zsmul_oangle_smul_left_self
@[simp]
theorem two_zsmul_oangle_smul_right_self (x : V) {r : ℝ} : (2 : ℤ) • o.oangle x (r • x) = 0 := by
rcases lt_or_le r 0 with (h | h) <;> simp [h]
#align orientation.two_zsmul_oangle_smul_right_self Orientation.two_zsmul_oangle_smul_right_self
@[simp]
theorem two_zsmul_oangle_smul_smul_self (x : V) {r₁ r₂ : ℝ} :
(2 : ℤ) • o.oangle (r₁ • x) (r₂ • x) = 0 := by by_cases h : r₁ = 0 <;> simp [h]
#align orientation.two_zsmul_oangle_smul_smul_self Orientation.two_zsmul_oangle_smul_smul_self
theorem two_zsmul_oangle_left_of_span_eq {x y : V} (z : V) (h : (ℝ ∙ x) = ℝ ∙ y) :
(2 : ℤ) • o.oangle x z = (2 : ℤ) • o.oangle y z := by
rw [Submodule.span_singleton_eq_span_singleton] at h
rcases h with ⟨r, rfl⟩
exact (o.two_zsmul_oangle_smul_left_of_ne_zero _ _ (Units.ne_zero _)).symm
#align orientation.two_zsmul_oangle_left_of_span_eq Orientation.two_zsmul_oangle_left_of_span_eq
theorem two_zsmul_oangle_right_of_span_eq (x : V) {y z : V} (h : (ℝ ∙ y) = ℝ ∙ z) :
(2 : ℤ) • o.oangle x y = (2 : ℤ) • o.oangle x z := by
rw [Submodule.span_singleton_eq_span_singleton] at h
rcases h with ⟨r, rfl⟩
exact (o.two_zsmul_oangle_smul_right_of_ne_zero _ _ (Units.ne_zero _)).symm
#align orientation.two_zsmul_oangle_right_of_span_eq Orientation.two_zsmul_oangle_right_of_span_eq
| Mathlib/Geometry/Euclidean/Angle/Oriented/Basic.lean | 398 | 400 | theorem two_zsmul_oangle_of_span_eq_of_span_eq {w x y z : V} (hwx : (ℝ ∙ w) = ℝ ∙ x)
(hyz : (ℝ ∙ y) = ℝ ∙ z) : (2 : ℤ) • o.oangle w y = (2 : ℤ) • o.oangle x z := by |
rw [o.two_zsmul_oangle_left_of_span_eq y hwx, o.two_zsmul_oangle_right_of_span_eq x hyz]
|
import Mathlib.RingTheory.Ideal.IsPrimary
import Mathlib.RingTheory.Localization.AtPrime
import Mathlib.Order.Minimal
#align_import ring_theory.ideal.minimal_prime from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a"
section
variable {R S : Type*} [CommSemiring R] [CommSemiring S] (I J : Ideal R)
protected def Ideal.minimalPrimes : Set (Ideal R) :=
minimals (· ≤ ·) { p | p.IsPrime ∧ I ≤ p }
#align ideal.minimal_primes Ideal.minimalPrimes
variable (R) in
def minimalPrimes : Set (Ideal R) :=
Ideal.minimalPrimes ⊥
#align minimal_primes minimalPrimes
lemma minimalPrimes_eq_minimals : minimalPrimes R = minimals (· ≤ ·) (setOf Ideal.IsPrime) :=
congr_arg (minimals (· ≤ ·)) (by simp)
variable {I J}
theorem Ideal.exists_minimalPrimes_le [J.IsPrime] (e : I ≤ J) : ∃ p ∈ I.minimalPrimes, p ≤ J := by
suffices
∃ m ∈ { p : (Ideal R)ᵒᵈ | Ideal.IsPrime p ∧ I ≤ OrderDual.ofDual p },
OrderDual.toDual J ≤ m ∧ ∀ z ∈ { p : (Ideal R)ᵒᵈ | Ideal.IsPrime p ∧ I ≤ p }, m ≤ z → z = m by
obtain ⟨p, h₁, h₂, h₃⟩ := this
simp_rw [← @eq_comm _ p] at h₃
exact ⟨p, ⟨h₁, fun a b c => le_of_eq (h₃ a b c)⟩, h₂⟩
apply zorn_nonempty_partialOrder₀
swap
· refine ⟨show J.IsPrime by infer_instance, e⟩
rintro (c : Set (Ideal R)) hc hc' J' hJ'
refine
⟨OrderDual.toDual (sInf c),
⟨Ideal.sInf_isPrime_of_isChain ⟨J', hJ'⟩ hc'.symm fun x hx => (hc hx).1, ?_⟩, ?_⟩
· rw [OrderDual.ofDual_toDual, le_sInf_iff]
exact fun _ hx => (hc hx).2
· rintro z hz
rw [OrderDual.le_toDual]
exact sInf_le hz
#align ideal.exists_minimal_primes_le Ideal.exists_minimalPrimes_le
@[simp]
theorem Ideal.radical_minimalPrimes : I.radical.minimalPrimes = I.minimalPrimes := by
rw [Ideal.minimalPrimes, Ideal.minimalPrimes]
ext p
refine ⟨?_, ?_⟩ <;> rintro ⟨⟨a, ha⟩, b⟩
· refine ⟨⟨a, a.radical_le_iff.1 ha⟩, ?_⟩
simp only [Set.mem_setOf_eq, and_imp] at *
exact fun _ h2 h3 h4 => b h2 (h2.radical_le_iff.2 h3) h4
· refine ⟨⟨a, a.radical_le_iff.2 ha⟩, ?_⟩
simp only [Set.mem_setOf_eq, and_imp] at *
exact fun _ h2 h3 h4 => b h2 (h2.radical_le_iff.1 h3) h4
#align ideal.radical_minimal_primes Ideal.radical_minimalPrimes
@[simp]
theorem Ideal.sInf_minimalPrimes : sInf I.minimalPrimes = I.radical := by
rw [I.radical_eq_sInf]
apply le_antisymm
· intro x hx
rw [Ideal.mem_sInf] at hx ⊢
rintro J ⟨e, hJ⟩
obtain ⟨p, hp, hp'⟩ := Ideal.exists_minimalPrimes_le e
exact hp' (hx hp)
· apply sInf_le_sInf _
intro I hI
exact hI.1.symm
#align ideal.Inf_minimal_primes Ideal.sInf_minimalPrimes
theorem Ideal.exists_comap_eq_of_mem_minimalPrimes_of_injective {f : R →+* S}
(hf : Function.Injective f) (p) (H : p ∈ minimalPrimes R) :
∃ p' : Ideal S, p'.IsPrime ∧ p'.comap f = p := by
have := H.1.1
have : Nontrivial (Localization (Submonoid.map f p.primeCompl)) := by
refine ⟨⟨1, 0, ?_⟩⟩
convert (IsLocalization.map_injective_of_injective p.primeCompl (Localization.AtPrime p)
(Localization <| p.primeCompl.map f) hf).ne one_ne_zero
· rw [map_one]
· rw [map_zero]
obtain ⟨M, hM⟩ := Ideal.exists_maximal (Localization (Submonoid.map f p.primeCompl))
refine ⟨M.comap (algebraMap S <| Localization (Submonoid.map f p.primeCompl)), inferInstance, ?_⟩
rw [Ideal.comap_comap, ← @IsLocalization.map_comp _ _ _ _ _ _ _ _ Localization.isLocalization
_ _ _ _ p.primeCompl.le_comap_map _ Localization.isLocalization,
← Ideal.comap_comap]
suffices _ ≤ p by exact this.antisymm (H.2 ⟨inferInstance, bot_le⟩ this)
intro x hx
by_contra h
apply hM.ne_top
apply M.eq_top_of_isUnit_mem hx
apply IsUnit.map
apply IsLocalization.map_units _ (show p.primeCompl from ⟨x, h⟩)
#align ideal.exists_comap_eq_of_mem_minimal_primes_of_injective Ideal.exists_comap_eq_of_mem_minimalPrimes_of_injective
end
section
variable {R S : Type*} [CommRing R] [CommRing S] {I J : Ideal R}
theorem Ideal.exists_comap_eq_of_mem_minimalPrimes {I : Ideal S} (f : R →+* S) (p)
(H : p ∈ (I.comap f).minimalPrimes) : ∃ p' : Ideal S, p'.IsPrime ∧ I ≤ p' ∧ p'.comap f = p := by
have := H.1.1
let f' := (Ideal.Quotient.mk I).comp f
have e : RingHom.ker f' = I.comap f := by
ext1
exact Submodule.Quotient.mk_eq_zero _
have : RingHom.ker (Ideal.Quotient.mk <| RingHom.ker f') ≤ p := by
rw [Ideal.mk_ker, e]
exact H.1.2
suffices _ by
have ⟨p', hp₁, hp₂⟩ := Ideal.exists_comap_eq_of_mem_minimalPrimes_of_injective
(RingHom.kerLift_injective f') (p.map <| Ideal.Quotient.mk <| RingHom.ker f') this
refine ⟨p'.comap <| Ideal.Quotient.mk I, Ideal.IsPrime.comap _, ?_, ?_⟩
· exact Ideal.mk_ker.symm.trans_le (Ideal.comap_mono bot_le)
· convert congr_arg (Ideal.comap <| Ideal.Quotient.mk <| RingHom.ker f') hp₂
rwa [Ideal.comap_map_of_surjective (Ideal.Quotient.mk <| RingHom.ker f')
Ideal.Quotient.mk_surjective, eq_comm, sup_eq_left]
refine ⟨⟨?_, bot_le⟩, ?_⟩
· apply Ideal.map_isPrime_of_surjective _ this
exact Ideal.Quotient.mk_surjective
· rintro q ⟨hq, -⟩ hq'
rw [← Ideal.map_comap_of_surjective
(Ideal.Quotient.mk (RingHom.ker ((Ideal.Quotient.mk I).comp f)))
Ideal.Quotient.mk_surjective q]
apply Ideal.map_mono
apply H.2
· refine ⟨inferInstance, (Ideal.mk_ker.trans e).symm.trans_le (Ideal.comap_mono bot_le)⟩
· refine (Ideal.comap_mono hq').trans ?_
rw [Ideal.comap_map_of_surjective]
exacts [sup_le rfl.le this, Ideal.Quotient.mk_surjective]
#align ideal.exists_comap_eq_of_mem_minimal_primes Ideal.exists_comap_eq_of_mem_minimalPrimes
theorem Ideal.exists_minimalPrimes_comap_eq {I : Ideal S} (f : R →+* S) (p)
(H : p ∈ (I.comap f).minimalPrimes) : ∃ p' ∈ I.minimalPrimes, Ideal.comap f p' = p := by
obtain ⟨p', h₁, h₂, h₃⟩ := Ideal.exists_comap_eq_of_mem_minimalPrimes f p H
obtain ⟨q, hq, hq'⟩ := Ideal.exists_minimalPrimes_le h₂
refine ⟨q, hq, Eq.symm ?_⟩
have := hq.1.1
have := (Ideal.comap_mono hq').trans_eq h₃
exact (H.2 ⟨inferInstance, Ideal.comap_mono hq.1.2⟩ this).antisymm this
#align ideal.exists_minimal_primes_comap_eq Ideal.exists_minimalPrimes_comap_eq
theorem Ideal.minimal_primes_comap_of_surjective {f : R →+* S} (hf : Function.Surjective f)
{I J : Ideal S} (h : J ∈ I.minimalPrimes) : J.comap f ∈ (I.comap f).minimalPrimes := by
have := h.1.1
refine ⟨⟨inferInstance, Ideal.comap_mono h.1.2⟩, ?_⟩
rintro K ⟨hK, e₁⟩ e₂
have : RingHom.ker f ≤ K := (Ideal.comap_mono bot_le).trans e₁
rw [← sup_eq_left.mpr this, RingHom.ker_eq_comap_bot, ← Ideal.comap_map_of_surjective f hf]
apply Ideal.comap_mono _
apply h.2 _ _
· exact ⟨Ideal.map_isPrime_of_surjective hf this, Ideal.le_map_of_comap_le_of_surjective f hf e₁⟩
· exact Ideal.map_le_of_le_comap e₂
#align ideal.mimimal_primes_comap_of_surjective Ideal.minimal_primes_comap_of_surjective
theorem Ideal.comap_minimalPrimes_eq_of_surjective {f : R →+* S} (hf : Function.Surjective f)
(I : Ideal S) : (I.comap f).minimalPrimes = Ideal.comap f '' I.minimalPrimes := by
ext J
constructor
· intro H
obtain ⟨p, h, rfl⟩ := Ideal.exists_minimalPrimes_comap_eq f J H
exact ⟨p, h, rfl⟩
· rintro ⟨J, hJ, rfl⟩
exact Ideal.minimal_primes_comap_of_surjective hf hJ
#align ideal.comap_minimal_primes_eq_of_surjective Ideal.comap_minimalPrimes_eq_of_surjective
theorem Ideal.minimalPrimes_eq_comap :
I.minimalPrimes = Ideal.comap (Ideal.Quotient.mk I) '' minimalPrimes (R ⧸ I) := by
rw [minimalPrimes, ← Ideal.comap_minimalPrimes_eq_of_surjective Ideal.Quotient.mk_surjective,
← RingHom.ker_eq_comap_bot, Ideal.mk_ker]
#align ideal.minimal_primes_eq_comap Ideal.minimalPrimes_eq_comap
theorem Ideal.minimalPrimes_eq_subsingleton (hI : I.IsPrimary) : I.minimalPrimes = {I.radical} := by
ext J
constructor
· exact fun H =>
let e := H.1.1.radical_le_iff.mpr H.1.2
(H.2 ⟨Ideal.isPrime_radical hI, Ideal.le_radical⟩ e).antisymm e
· rintro (rfl : J = I.radical)
exact ⟨⟨Ideal.isPrime_radical hI, Ideal.le_radical⟩, fun _ H _ => H.1.radical_le_iff.mpr H.2⟩
#align ideal.minimal_primes_eq_subsingleton Ideal.minimalPrimes_eq_subsingleton
theorem Ideal.minimalPrimes_eq_subsingleton_self [I.IsPrime] : I.minimalPrimes = {I} := by
ext J
constructor
· exact fun H => (H.2 ⟨inferInstance, rfl.le⟩ H.1.2).antisymm H.1.2
· rintro (rfl : J = I)
exact ⟨⟨inferInstance, rfl.le⟩, fun _ h _ => h.2⟩
#align ideal.minimal_primes_eq_subsingleton_self Ideal.minimalPrimes_eq_subsingleton_self
end
namespace Localization.AtPrime
variable {R : Type*} [CommSemiring R] {I : Ideal R} [hI : I.IsPrime] (hMin : I ∈ minimalPrimes R)
theorem _root_.IsLocalization.AtPrime.prime_unique_of_minimal {S} [CommSemiring S] [Algebra R S]
[IsLocalization.AtPrime S I] {J K : Ideal S} [J.IsPrime] [K.IsPrime] : J = K :=
haveI : Subsingleton {i : Ideal R // i.IsPrime ∧ i ≤ I} := ⟨fun i₁ i₂ ↦ Subtype.ext <| by
rw [minimalPrimes_eq_minimals] at hMin
rw [← eq_of_mem_minimals hMin i₁.2.1 i₁.2.2, ← eq_of_mem_minimals hMin i₂.2.1 i₂.2.2]⟩
Subtype.ext_iff.mp <| (IsLocalization.AtPrime.orderIsoOfPrime S I).injective
(a₁ := ⟨J, ‹_›⟩) (a₂ := ⟨K, ‹_›⟩) (Subsingleton.elim _ _)
theorem prime_unique_of_minimal (J : Ideal (Localization I.primeCompl)) [J.IsPrime] :
J = LocalRing.maximalIdeal (Localization I.primeCompl) :=
IsLocalization.AtPrime.prime_unique_of_minimal hMin
theorem nilpotent_iff_mem_maximal_of_minimal {x : _} :
IsNilpotent x ↔ x ∈ LocalRing.maximalIdeal (Localization I.primeCompl) := by
rw [nilpotent_iff_mem_prime]
exact ⟨(· (LocalRing.maximalIdeal _) (Ideal.IsMaximal.isPrime' _)), fun _ J _ =>
by simpa [prime_unique_of_minimal hMin J]⟩
| Mathlib/RingTheory/Ideal/MinimalPrime.lean | 249 | 251 | theorem nilpotent_iff_not_unit_of_minimal {x : Localization I.primeCompl} :
IsNilpotent x ↔ x ∈ nonunits _ := by |
simpa only [← LocalRing.mem_maximalIdeal] using nilpotent_iff_mem_maximal_of_minimal hMin
|
import Mathlib.Topology.Algebra.Module.WeakDual
import Mathlib.MeasureTheory.Integral.BoundedContinuousFunction
import Mathlib.MeasureTheory.Measure.HasOuterApproxClosed
#align_import measure_theory.measure.finite_measure from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982"
noncomputable section
open MeasureTheory
open Set
open Filter
open BoundedContinuousFunction
open scoped Topology ENNReal NNReal BoundedContinuousFunction
namespace MeasureTheory
namespace FiniteMeasure
section FiniteMeasure
variable {Ω : Type*} [MeasurableSpace Ω]
def _root_.MeasureTheory.FiniteMeasure (Ω : Type*) [MeasurableSpace Ω] : Type _ :=
{ μ : Measure Ω // IsFiniteMeasure μ }
#align measure_theory.finite_measure MeasureTheory.FiniteMeasure
-- Porting note: as with other subtype synonyms (e.g., `ℝ≥0`, we need a new function for the
-- coercion instead of relying on `Subtype.val`.
@[coe]
def toMeasure : FiniteMeasure Ω → Measure Ω := Subtype.val
instance instCoe : Coe (FiniteMeasure Ω) (MeasureTheory.Measure Ω) where
coe := toMeasure
instance isFiniteMeasure (μ : FiniteMeasure Ω) : IsFiniteMeasure (μ : Measure Ω) :=
μ.prop
#align measure_theory.finite_measure.is_finite_measure MeasureTheory.FiniteMeasure.isFiniteMeasure
@[simp]
theorem val_eq_toMeasure (ν : FiniteMeasure Ω) : ν.val = (ν : Measure Ω) :=
rfl
#align measure_theory.finite_measure.val_eq_to_measure MeasureTheory.FiniteMeasure.val_eq_toMeasure
theorem toMeasure_injective : Function.Injective ((↑) : FiniteMeasure Ω → Measure Ω) :=
Subtype.coe_injective
#align measure_theory.finite_measure.coe_injective MeasureTheory.FiniteMeasure.toMeasure_injective
instance instFunLike : FunLike (FiniteMeasure Ω) (Set Ω) ℝ≥0 where
coe μ s := ((μ : Measure Ω) s).toNNReal
coe_injective' μ ν h := toMeasure_injective $ Measure.ext fun s _ ↦ by
simpa [ENNReal.toNNReal_eq_toNNReal_iff, measure_ne_top] using congr_fun h s
lemma coeFn_def (μ : FiniteMeasure Ω) : μ = fun s ↦ ((μ : Measure Ω) s).toNNReal := rfl
#align measure_theory.finite_measure.coe_fn_eq_to_nnreal_coe_fn_to_measure MeasureTheory.FiniteMeasure.coeFn_def
lemma coeFn_mk (μ : Measure Ω) (hμ) :
DFunLike.coe (F := FiniteMeasure Ω) ⟨μ, hμ⟩ = fun s ↦ (μ s).toNNReal := rfl
@[simp, norm_cast]
lemma mk_apply (μ : Measure Ω) (hμ) (s : Set Ω) :
DFunLike.coe (F := FiniteMeasure Ω) ⟨μ, hμ⟩ s = (μ s).toNNReal := rfl
@[simp]
theorem ennreal_coeFn_eq_coeFn_toMeasure (ν : FiniteMeasure Ω) (s : Set Ω) :
(ν s : ℝ≥0∞) = (ν : Measure Ω) s :=
ENNReal.coe_toNNReal (measure_lt_top (↑ν) s).ne
#align measure_theory.finite_measure.ennreal_coe_fn_eq_coe_fn_to_measure MeasureTheory.FiniteMeasure.ennreal_coeFn_eq_coeFn_toMeasure
theorem apply_mono (μ : FiniteMeasure Ω) {s₁ s₂ : Set Ω} (h : s₁ ⊆ s₂) : μ s₁ ≤ μ s₂ := by
change ((μ : Measure Ω) s₁).toNNReal ≤ ((μ : Measure Ω) s₂).toNNReal
have key : (μ : Measure Ω) s₁ ≤ (μ : Measure Ω) s₂ := (μ : Measure Ω).mono h
apply (ENNReal.toNNReal_le_toNNReal (measure_ne_top _ s₁) (measure_ne_top _ s₂)).mpr key
#align measure_theory.finite_measure.apply_mono MeasureTheory.FiniteMeasure.apply_mono
def mass (μ : FiniteMeasure Ω) : ℝ≥0 :=
μ univ
#align measure_theory.finite_measure.mass MeasureTheory.FiniteMeasure.mass
@[simp] theorem apply_le_mass (μ : FiniteMeasure Ω) (s : Set Ω) : μ s ≤ μ.mass := by
simpa using apply_mono μ (subset_univ s)
@[simp]
theorem ennreal_mass {μ : FiniteMeasure Ω} : (μ.mass : ℝ≥0∞) = (μ : Measure Ω) univ :=
ennreal_coeFn_eq_coeFn_toMeasure μ Set.univ
#align measure_theory.finite_measure.ennreal_mass MeasureTheory.FiniteMeasure.ennreal_mass
instance instZero : Zero (FiniteMeasure Ω) where zero := ⟨0, MeasureTheory.isFiniteMeasureZero⟩
#align measure_theory.finite_measure.has_zero MeasureTheory.FiniteMeasure.instZero
@[simp, norm_cast] lemma coeFn_zero : ⇑(0 : FiniteMeasure Ω) = 0 := rfl
#align measure_theory.finite_measure.coe_fn_zero MeasureTheory.FiniteMeasure.coeFn_zero
@[simp]
theorem zero_mass : (0 : FiniteMeasure Ω).mass = 0 :=
rfl
#align measure_theory.finite_measure.zero.mass MeasureTheory.FiniteMeasure.zero_mass
@[simp]
theorem mass_zero_iff (μ : FiniteMeasure Ω) : μ.mass = 0 ↔ μ = 0 := by
refine ⟨fun μ_mass => ?_, fun hμ => by simp only [hμ, zero_mass]⟩
apply toMeasure_injective
apply Measure.measure_univ_eq_zero.mp
rwa [← ennreal_mass, ENNReal.coe_eq_zero]
#align measure_theory.finite_measure.mass_zero_iff MeasureTheory.FiniteMeasure.mass_zero_iff
theorem mass_nonzero_iff (μ : FiniteMeasure Ω) : μ.mass ≠ 0 ↔ μ ≠ 0 := by
rw [not_iff_not]
exact FiniteMeasure.mass_zero_iff μ
#align measure_theory.finite_measure.mass_nonzero_iff MeasureTheory.FiniteMeasure.mass_nonzero_iff
@[ext]
theorem eq_of_forall_toMeasure_apply_eq (μ ν : FiniteMeasure Ω)
(h : ∀ s : Set Ω, MeasurableSet s → (μ : Measure Ω) s = (ν : Measure Ω) s) : μ = ν := by
apply Subtype.ext
ext1 s s_mble
exact h s s_mble
#align measure_theory.finite_measure.eq_of_forall_measure_apply_eq MeasureTheory.FiniteMeasure.eq_of_forall_toMeasure_apply_eq
theorem eq_of_forall_apply_eq (μ ν : FiniteMeasure Ω)
(h : ∀ s : Set Ω, MeasurableSet s → μ s = ν s) : μ = ν := by
ext1 s s_mble
simpa [ennreal_coeFn_eq_coeFn_toMeasure] using congr_arg ((↑) : ℝ≥0 → ℝ≥0∞) (h s s_mble)
#align measure_theory.finite_measure.eq_of_forall_apply_eq MeasureTheory.FiniteMeasure.eq_of_forall_apply_eq
instance instInhabited : Inhabited (FiniteMeasure Ω) :=
⟨0⟩
instance instAdd : Add (FiniteMeasure Ω) where add μ ν := ⟨μ + ν, MeasureTheory.isFiniteMeasureAdd⟩
variable {R : Type*} [SMul R ℝ≥0] [SMul R ℝ≥0∞] [IsScalarTower R ℝ≥0 ℝ≥0∞]
[IsScalarTower R ℝ≥0∞ ℝ≥0∞]
instance instSMul : SMul R (FiniteMeasure Ω) where
smul (c : R) μ := ⟨c • (μ : Measure Ω), MeasureTheory.isFiniteMeasureSMulOfNNRealTower⟩
@[simp, norm_cast]
theorem toMeasure_zero : ((↑) : FiniteMeasure Ω → Measure Ω) 0 = 0 :=
rfl
#align measure_theory.finite_measure.coe_zero MeasureTheory.FiniteMeasure.toMeasure_zero
-- Porting note: with `simp` here the `coeFn` lemmas below fall prey to `simpNF`: the LHS simplifies
@[norm_cast]
theorem toMeasure_add (μ ν : FiniteMeasure Ω) : ↑(μ + ν) = (↑μ + ↑ν : Measure Ω) :=
rfl
#align measure_theory.finite_measure.coe_add MeasureTheory.FiniteMeasure.toMeasure_add
@[simp, norm_cast]
theorem toMeasure_smul (c : R) (μ : FiniteMeasure Ω) : ↑(c • μ) = c • (μ : Measure Ω) :=
rfl
#align measure_theory.finite_measure.coe_smul MeasureTheory.FiniteMeasure.toMeasure_smul
@[simp, norm_cast]
theorem coeFn_add (μ ν : FiniteMeasure Ω) : (⇑(μ + ν) : Set Ω → ℝ≥0) = (⇑μ + ⇑ν : Set Ω → ℝ≥0) := by
funext
simp only [Pi.add_apply, ← ENNReal.coe_inj, ne_eq, ennreal_coeFn_eq_coeFn_toMeasure,
ENNReal.coe_add]
norm_cast
#align measure_theory.finite_measure.coe_fn_add MeasureTheory.FiniteMeasure.coeFn_add
@[simp, norm_cast]
theorem coeFn_smul [IsScalarTower R ℝ≥0 ℝ≥0] (c : R) (μ : FiniteMeasure Ω) :
(⇑(c • μ) : Set Ω → ℝ≥0) = c • (⇑μ : Set Ω → ℝ≥0) := by
funext; simp [← ENNReal.coe_inj, ENNReal.coe_smul]
#align measure_theory.finite_measure.coe_fn_smul MeasureTheory.FiniteMeasure.coeFn_smul
instance instAddCommMonoid : AddCommMonoid (FiniteMeasure Ω) :=
toMeasure_injective.addCommMonoid (↑) toMeasure_zero toMeasure_add fun _ _ => toMeasure_smul _ _
@[simps]
def toMeasureAddMonoidHom : FiniteMeasure Ω →+ Measure Ω where
toFun := (↑)
map_zero' := toMeasure_zero
map_add' := toMeasure_add
#align measure_theory.finite_measure.coe_add_monoid_hom MeasureTheory.FiniteMeasure.toMeasureAddMonoidHom
instance {Ω : Type*} [MeasurableSpace Ω] : Module ℝ≥0 (FiniteMeasure Ω) :=
Function.Injective.module _ toMeasureAddMonoidHom toMeasure_injective toMeasure_smul
@[simp]
theorem smul_apply [IsScalarTower R ℝ≥0 ℝ≥0] (c : R) (μ : FiniteMeasure Ω) (s : Set Ω) :
(c • μ) s = c • μ s := by
rw [coeFn_smul, Pi.smul_apply]
#align measure_theory.finite_measure.coe_fn_smul_apply MeasureTheory.FiniteMeasure.smul_apply
def restrict (μ : FiniteMeasure Ω) (A : Set Ω) : FiniteMeasure Ω where
val := (μ : Measure Ω).restrict A
property := MeasureTheory.isFiniteMeasureRestrict (μ : Measure Ω) A
#align measure_theory.finite_measure.restrict MeasureTheory.FiniteMeasure.restrict
theorem restrict_measure_eq (μ : FiniteMeasure Ω) (A : Set Ω) :
(μ.restrict A : Measure Ω) = (μ : Measure Ω).restrict A :=
rfl
#align measure_theory.finite_measure.restrict_measure_eq MeasureTheory.FiniteMeasure.restrict_measure_eq
theorem restrict_apply_measure (μ : FiniteMeasure Ω) (A : Set Ω) {s : Set Ω}
(s_mble : MeasurableSet s) : (μ.restrict A : Measure Ω) s = (μ : Measure Ω) (s ∩ A) :=
Measure.restrict_apply s_mble
#align measure_theory.finite_measure.restrict_apply_measure MeasureTheory.FiniteMeasure.restrict_apply_measure
theorem restrict_apply (μ : FiniteMeasure Ω) (A : Set Ω) {s : Set Ω} (s_mble : MeasurableSet s) :
(μ.restrict A) s = μ (s ∩ A) := by
apply congr_arg ENNReal.toNNReal
exact Measure.restrict_apply s_mble
#align measure_theory.finite_measure.restrict_apply MeasureTheory.FiniteMeasure.restrict_apply
theorem restrict_mass (μ : FiniteMeasure Ω) (A : Set Ω) : (μ.restrict A).mass = μ A := by
simp only [mass, restrict_apply μ A MeasurableSet.univ, univ_inter]
#align measure_theory.finite_measure.restrict_mass MeasureTheory.FiniteMeasure.restrict_mass
theorem restrict_eq_zero_iff (μ : FiniteMeasure Ω) (A : Set Ω) : μ.restrict A = 0 ↔ μ A = 0 := by
rw [← mass_zero_iff, restrict_mass]
#align measure_theory.finite_measure.restrict_eq_zero_iff MeasureTheory.FiniteMeasure.restrict_eq_zero_iff
theorem restrict_nonzero_iff (μ : FiniteMeasure Ω) (A : Set Ω) : μ.restrict A ≠ 0 ↔ μ A ≠ 0 := by
rw [← mass_nonzero_iff, restrict_mass]
#align measure_theory.finite_measure.restrict_nonzero_iff MeasureTheory.FiniteMeasure.restrict_nonzero_iff
variable [TopologicalSpace Ω]
theorem ext_of_forall_lintegral_eq [HasOuterApproxClosed Ω] [BorelSpace Ω]
{μ ν : FiniteMeasure Ω} (h : ∀ (f : Ω →ᵇ ℝ≥0), ∫⁻ x, f x ∂μ = ∫⁻ x, f x ∂ν) :
μ = ν := by
apply Subtype.ext
change (μ : Measure Ω) = (ν : Measure Ω)
exact ext_of_forall_lintegral_eq_of_IsFiniteMeasure h
def testAgainstNN (μ : FiniteMeasure Ω) (f : Ω →ᵇ ℝ≥0) : ℝ≥0 :=
(∫⁻ ω, f ω ∂(μ : Measure Ω)).toNNReal
#align measure_theory.finite_measure.test_against_nn MeasureTheory.FiniteMeasure.testAgainstNN
@[simp]
theorem testAgainstNN_coe_eq {μ : FiniteMeasure Ω} {f : Ω →ᵇ ℝ≥0} :
(μ.testAgainstNN f : ℝ≥0∞) = ∫⁻ ω, f ω ∂(μ : Measure Ω) :=
ENNReal.coe_toNNReal (f.lintegral_lt_top_of_nnreal _).ne
#align measure_theory.finite_measure.test_against_nn_coe_eq MeasureTheory.FiniteMeasure.testAgainstNN_coe_eq
theorem testAgainstNN_const (μ : FiniteMeasure Ω) (c : ℝ≥0) :
μ.testAgainstNN (BoundedContinuousFunction.const Ω c) = c * μ.mass := by
simp [← ENNReal.coe_inj]
#align measure_theory.finite_measure.test_against_nn_const MeasureTheory.FiniteMeasure.testAgainstNN_const
theorem testAgainstNN_mono (μ : FiniteMeasure Ω) {f g : Ω →ᵇ ℝ≥0} (f_le_g : (f : Ω → ℝ≥0) ≤ g) :
μ.testAgainstNN f ≤ μ.testAgainstNN g := by
simp only [← ENNReal.coe_le_coe, testAgainstNN_coe_eq]
gcongr
apply f_le_g
#align measure_theory.finite_measure.test_against_nn_mono MeasureTheory.FiniteMeasure.testAgainstNN_mono
@[simp]
theorem testAgainstNN_zero (μ : FiniteMeasure Ω) : μ.testAgainstNN 0 = 0 := by
simpa only [zero_mul] using μ.testAgainstNN_const 0
#align measure_theory.finite_measure.test_against_nn_zero MeasureTheory.FiniteMeasure.testAgainstNN_zero
@[simp]
theorem testAgainstNN_one (μ : FiniteMeasure Ω) : μ.testAgainstNN 1 = μ.mass := by
simp only [testAgainstNN, coe_one, Pi.one_apply, ENNReal.coe_one, lintegral_one]
rfl
#align measure_theory.finite_measure.test_against_nn_one MeasureTheory.FiniteMeasure.testAgainstNN_one
@[simp]
theorem zero_testAgainstNN_apply (f : Ω →ᵇ ℝ≥0) : (0 : FiniteMeasure Ω).testAgainstNN f = 0 := by
simp only [testAgainstNN, toMeasure_zero, lintegral_zero_measure, ENNReal.zero_toNNReal]
#align measure_theory.finite_measure.zero.test_against_nn_apply MeasureTheory.FiniteMeasure.zero_testAgainstNN_apply
| Mathlib/MeasureTheory/Measure/FiniteMeasure.lean | 373 | 375 | theorem zero_testAgainstNN : (0 : FiniteMeasure Ω).testAgainstNN = 0 := by |
funext;
simp only [zero_testAgainstNN_apply, Pi.zero_apply]
|
import Mathlib.Data.ZMod.Quotient
#align_import group_theory.complement from "leanprover-community/mathlib"@"6ca1a09bc9aa75824bf97388c9e3b441fc4ccf3f"
open Set
open scoped Pointwise
namespace Subgroup
variable {G : Type*} [Group G] (H K : Subgroup G) (S T : Set G)
@[to_additive "`S` and `T` are complements if `(+) : S × T → G` is a bijection"]
def IsComplement : Prop :=
Function.Bijective fun x : S × T => x.1.1 * x.2.1
#align subgroup.is_complement Subgroup.IsComplement
#align add_subgroup.is_complement AddSubgroup.IsComplement
@[to_additive "`H` and `K` are complements if `(+) : H × K → G` is a bijection"]
abbrev IsComplement' :=
IsComplement (H : Set G) (K : Set G)
#align subgroup.is_complement' Subgroup.IsComplement'
#align add_subgroup.is_complement' AddSubgroup.IsComplement'
@[to_additive "The set of left-complements of `T : Set G`"]
def leftTransversals : Set (Set G) :=
{ S : Set G | IsComplement S T }
#align subgroup.left_transversals Subgroup.leftTransversals
#align add_subgroup.left_transversals AddSubgroup.leftTransversals
@[to_additive "The set of right-complements of `S : Set G`"]
def rightTransversals : Set (Set G) :=
{ T : Set G | IsComplement S T }
#align subgroup.right_transversals Subgroup.rightTransversals
#align add_subgroup.right_transversals AddSubgroup.rightTransversals
variable {H K S T}
@[to_additive]
theorem isComplement'_def : IsComplement' H K ↔ IsComplement (H : Set G) (K : Set G) :=
Iff.rfl
#align subgroup.is_complement'_def Subgroup.isComplement'_def
#align add_subgroup.is_complement'_def AddSubgroup.isComplement'_def
@[to_additive]
theorem isComplement_iff_existsUnique :
IsComplement S T ↔ ∀ g : G, ∃! x : S × T, x.1.1 * x.2.1 = g :=
Function.bijective_iff_existsUnique _
#align subgroup.is_complement_iff_exists_unique Subgroup.isComplement_iff_existsUnique
#align add_subgroup.is_complement_iff_exists_unique AddSubgroup.isComplement_iff_existsUnique
@[to_additive]
theorem IsComplement.existsUnique (h : IsComplement S T) (g : G) :
∃! x : S × T, x.1.1 * x.2.1 = g :=
isComplement_iff_existsUnique.mp h g
#align subgroup.is_complement.exists_unique Subgroup.IsComplement.existsUnique
#align add_subgroup.is_complement.exists_unique AddSubgroup.IsComplement.existsUnique
@[to_additive]
theorem IsComplement'.symm (h : IsComplement' H K) : IsComplement' K H := by
let ϕ : H × K ≃ K × H :=
Equiv.mk (fun x => ⟨x.2⁻¹, x.1⁻¹⟩) (fun x => ⟨x.2⁻¹, x.1⁻¹⟩)
(fun x => Prod.ext (inv_inv _) (inv_inv _)) fun x => Prod.ext (inv_inv _) (inv_inv _)
let ψ : G ≃ G := Equiv.mk (fun g : G => g⁻¹) (fun g : G => g⁻¹) inv_inv inv_inv
suffices hf : (ψ ∘ fun x : H × K => x.1.1 * x.2.1) = (fun x : K × H => x.1.1 * x.2.1) ∘ ϕ by
rw [isComplement'_def, IsComplement, ← Equiv.bijective_comp ϕ]
apply (congr_arg Function.Bijective hf).mp -- Porting note: This was a `rw` in mathlib3
rwa [ψ.comp_bijective]
exact funext fun x => mul_inv_rev _ _
#align subgroup.is_complement'.symm Subgroup.IsComplement'.symm
#align add_subgroup.is_complement'.symm AddSubgroup.IsComplement'.symm
@[to_additive]
theorem isComplement'_comm : IsComplement' H K ↔ IsComplement' K H :=
⟨IsComplement'.symm, IsComplement'.symm⟩
#align subgroup.is_complement'_comm Subgroup.isComplement'_comm
#align add_subgroup.is_complement'_comm AddSubgroup.isComplement'_comm
@[to_additive]
theorem isComplement_univ_singleton {g : G} : IsComplement (univ : Set G) {g} :=
⟨fun ⟨_, _, rfl⟩ ⟨_, _, rfl⟩ h => Prod.ext (Subtype.ext (mul_right_cancel h)) rfl, fun x =>
⟨⟨⟨x * g⁻¹, ⟨⟩⟩, g, rfl⟩, inv_mul_cancel_right x g⟩⟩
#align subgroup.is_complement_top_singleton Subgroup.isComplement_univ_singleton
#align add_subgroup.is_complement_top_singleton AddSubgroup.isComplement_univ_singleton
@[to_additive]
theorem isComplement_singleton_univ {g : G} : IsComplement ({g} : Set G) univ :=
⟨fun ⟨⟨_, rfl⟩, _⟩ ⟨⟨_, rfl⟩, _⟩ h => Prod.ext rfl (Subtype.ext (mul_left_cancel h)), fun x =>
⟨⟨⟨g, rfl⟩, g⁻¹ * x, ⟨⟩⟩, mul_inv_cancel_left g x⟩⟩
#align subgroup.is_complement_singleton_top Subgroup.isComplement_singleton_univ
#align add_subgroup.is_complement_singleton_top AddSubgroup.isComplement_singleton_univ
@[to_additive]
theorem isComplement_singleton_left {g : G} : IsComplement {g} S ↔ S = univ := by
refine
⟨fun h => top_le_iff.mp fun x _ => ?_, fun h => (congr_arg _ h).mpr isComplement_singleton_univ⟩
obtain ⟨⟨⟨z, rfl : z = g⟩, y, _⟩, hy⟩ := h.2 (g * x)
rwa [← mul_left_cancel hy]
#align subgroup.is_complement_singleton_left Subgroup.isComplement_singleton_left
#align add_subgroup.is_complement_singleton_left AddSubgroup.isComplement_singleton_left
@[to_additive]
theorem isComplement_singleton_right {g : G} : IsComplement S {g} ↔ S = univ := by
refine
⟨fun h => top_le_iff.mp fun x _ => ?_, fun h => h ▸ isComplement_univ_singleton⟩
obtain ⟨y, hy⟩ := h.2 (x * g)
conv_rhs at hy => rw [← show y.2.1 = g from y.2.2]
rw [← mul_right_cancel hy]
exact y.1.2
#align subgroup.is_complement_singleton_right Subgroup.isComplement_singleton_right
#align add_subgroup.is_complement_singleton_right AddSubgroup.isComplement_singleton_right
@[to_additive]
theorem isComplement_univ_left : IsComplement univ S ↔ ∃ g : G, S = {g} := by
refine
⟨fun h => Set.exists_eq_singleton_iff_nonempty_subsingleton.mpr ⟨?_, fun a ha b hb => ?_⟩, ?_⟩
· obtain ⟨a, _⟩ := h.2 1
exact ⟨a.2.1, a.2.2⟩
· have : (⟨⟨_, mem_top a⁻¹⟩, ⟨a, ha⟩⟩ : (⊤ : Set G) × S) = ⟨⟨_, mem_top b⁻¹⟩, ⟨b, hb⟩⟩ :=
h.1 ((inv_mul_self a).trans (inv_mul_self b).symm)
exact Subtype.ext_iff.mp (Prod.ext_iff.mp this).2
· rintro ⟨g, rfl⟩
exact isComplement_univ_singleton
#align subgroup.is_complement_top_left Subgroup.isComplement_univ_left
#align add_subgroup.is_complement_top_left AddSubgroup.isComplement_univ_left
@[to_additive]
theorem isComplement_univ_right : IsComplement S univ ↔ ∃ g : G, S = {g} := by
refine
⟨fun h => Set.exists_eq_singleton_iff_nonempty_subsingleton.mpr ⟨?_, fun a ha b hb => ?_⟩, ?_⟩
· obtain ⟨a, _⟩ := h.2 1
exact ⟨a.1.1, a.1.2⟩
· have : (⟨⟨a, ha⟩, ⟨_, mem_top a⁻¹⟩⟩ : S × (⊤ : Set G)) = ⟨⟨b, hb⟩, ⟨_, mem_top b⁻¹⟩⟩ :=
h.1 ((mul_inv_self a).trans (mul_inv_self b).symm)
exact Subtype.ext_iff.mp (Prod.ext_iff.mp this).1
· rintro ⟨g, rfl⟩
exact isComplement_singleton_univ
#align subgroup.is_complement_top_right Subgroup.isComplement_univ_right
#align add_subgroup.is_complement_top_right AddSubgroup.isComplement_univ_right
@[to_additive]
lemma IsComplement.mul_eq (h : IsComplement S T) : S * T = univ :=
eq_univ_of_forall fun x ↦ by simpa [mem_mul] using (h.existsUnique x).exists
@[to_additive AddSubgroup.IsComplement.card_mul_card]
lemma IsComplement.card_mul_card (h : IsComplement S T) : Nat.card S * Nat.card T = Nat.card G :=
(Nat.card_prod _ _).symm.trans <| Nat.card_congr <| Equiv.ofBijective _ h
@[to_additive]
theorem isComplement'_top_bot : IsComplement' (⊤ : Subgroup G) ⊥ :=
isComplement_univ_singleton
#align subgroup.is_complement'_top_bot Subgroup.isComplement'_top_bot
#align add_subgroup.is_complement'_top_bot AddSubgroup.isComplement'_top_bot
@[to_additive]
theorem isComplement'_bot_top : IsComplement' (⊥ : Subgroup G) ⊤ :=
isComplement_singleton_univ
#align subgroup.is_complement'_bot_top Subgroup.isComplement'_bot_top
#align add_subgroup.is_complement'_bot_top AddSubgroup.isComplement'_bot_top
@[to_additive (attr := simp)]
theorem isComplement'_bot_left : IsComplement' ⊥ H ↔ H = ⊤ :=
isComplement_singleton_left.trans coe_eq_univ
#align subgroup.is_complement'_bot_left Subgroup.isComplement'_bot_left
#align add_subgroup.is_complement'_bot_left AddSubgroup.isComplement'_bot_left
@[to_additive (attr := simp)]
theorem isComplement'_bot_right : IsComplement' H ⊥ ↔ H = ⊤ :=
isComplement_singleton_right.trans coe_eq_univ
#align subgroup.is_complement'_bot_right Subgroup.isComplement'_bot_right
#align add_subgroup.is_complement'_bot_right AddSubgroup.isComplement'_bot_right
@[to_additive (attr := simp)]
theorem isComplement'_top_left : IsComplement' ⊤ H ↔ H = ⊥ :=
isComplement_univ_left.trans coe_eq_singleton
#align subgroup.is_complement'_top_left Subgroup.isComplement'_top_left
#align add_subgroup.is_complement'_top_left AddSubgroup.isComplement'_top_left
@[to_additive (attr := simp)]
theorem isComplement'_top_right : IsComplement' H ⊤ ↔ H = ⊥ :=
isComplement_univ_right.trans coe_eq_singleton
#align subgroup.is_complement'_top_right Subgroup.isComplement'_top_right
#align add_subgroup.is_complement'_top_right AddSubgroup.isComplement'_top_right
@[to_additive]
theorem mem_leftTransversals_iff_existsUnique_inv_mul_mem :
S ∈ leftTransversals T ↔ ∀ g : G, ∃! s : S, (s : G)⁻¹ * g ∈ T := by
rw [leftTransversals, Set.mem_setOf_eq, isComplement_iff_existsUnique]
refine ⟨fun h g => ?_, fun h g => ?_⟩
· obtain ⟨x, h1, h2⟩ := h g
exact
⟨x.1, (congr_arg (· ∈ T) (eq_inv_mul_of_mul_eq h1)).mp x.2.2, fun y hy =>
(Prod.ext_iff.mp (h2 ⟨y, (↑y)⁻¹ * g, hy⟩ (mul_inv_cancel_left ↑y g))).1⟩
· obtain ⟨x, h1, h2⟩ := h g
refine ⟨⟨x, (↑x)⁻¹ * g, h1⟩, mul_inv_cancel_left (↑x) g, fun y hy => ?_⟩
have hf := h2 y.1 ((congr_arg (· ∈ T) (eq_inv_mul_of_mul_eq hy)).mp y.2.2)
exact Prod.ext hf (Subtype.ext (eq_inv_mul_of_mul_eq (hf ▸ hy)))
#align subgroup.mem_left_transversals_iff_exists_unique_inv_mul_mem Subgroup.mem_leftTransversals_iff_existsUnique_inv_mul_mem
#align add_subgroup.mem_left_transversals_iff_exists_unique_neg_add_mem AddSubgroup.mem_leftTransversals_iff_existsUnique_neg_add_mem
@[to_additive]
theorem mem_rightTransversals_iff_existsUnique_mul_inv_mem :
S ∈ rightTransversals T ↔ ∀ g : G, ∃! s : S, g * (s : G)⁻¹ ∈ T := by
rw [rightTransversals, Set.mem_setOf_eq, isComplement_iff_existsUnique]
refine ⟨fun h g => ?_, fun h g => ?_⟩
· obtain ⟨x, h1, h2⟩ := h g
exact
⟨x.2, (congr_arg (· ∈ T) (eq_mul_inv_of_mul_eq h1)).mp x.1.2, fun y hy =>
(Prod.ext_iff.mp (h2 ⟨⟨g * (↑y)⁻¹, hy⟩, y⟩ (inv_mul_cancel_right g y))).2⟩
· obtain ⟨x, h1, h2⟩ := h g
refine ⟨⟨⟨g * (↑x)⁻¹, h1⟩, x⟩, inv_mul_cancel_right g x, fun y hy => ?_⟩
have hf := h2 y.2 ((congr_arg (· ∈ T) (eq_mul_inv_of_mul_eq hy)).mp y.1.2)
exact Prod.ext (Subtype.ext (eq_mul_inv_of_mul_eq (hf ▸ hy))) hf
#align subgroup.mem_right_transversals_iff_exists_unique_mul_inv_mem Subgroup.mem_rightTransversals_iff_existsUnique_mul_inv_mem
#align add_subgroup.mem_right_transversals_iff_exists_unique_add_neg_mem AddSubgroup.mem_rightTransversals_iff_existsUnique_add_neg_mem
@[to_additive]
theorem mem_leftTransversals_iff_existsUnique_quotient_mk''_eq :
S ∈ leftTransversals (H : Set G) ↔
∀ q : Quotient (QuotientGroup.leftRel H), ∃! s : S, Quotient.mk'' s.1 = q := by
simp_rw [mem_leftTransversals_iff_existsUnique_inv_mul_mem, SetLike.mem_coe, ←
QuotientGroup.eq']
exact ⟨fun h q => Quotient.inductionOn' q h, fun h g => h (Quotient.mk'' g)⟩
#align subgroup.mem_left_transversals_iff_exists_unique_quotient_mk'_eq Subgroup.mem_leftTransversals_iff_existsUnique_quotient_mk''_eq
#align add_subgroup.mem_left_transversals_iff_exists_unique_quotient_mk'_eq AddSubgroup.mem_leftTransversals_iff_existsUnique_quotient_mk''_eq
@[to_additive]
theorem mem_rightTransversals_iff_existsUnique_quotient_mk''_eq :
S ∈ rightTransversals (H : Set G) ↔
∀ q : Quotient (QuotientGroup.rightRel H), ∃! s : S, Quotient.mk'' s.1 = q := by
simp_rw [mem_rightTransversals_iff_existsUnique_mul_inv_mem, SetLike.mem_coe, ←
QuotientGroup.rightRel_apply, ← Quotient.eq'']
exact ⟨fun h q => Quotient.inductionOn' q h, fun h g => h (Quotient.mk'' g)⟩
#align subgroup.mem_right_transversals_iff_exists_unique_quotient_mk'_eq Subgroup.mem_rightTransversals_iff_existsUnique_quotient_mk''_eq
#align add_subgroup.mem_right_transversals_iff_exists_unique_quotient_mk'_eq AddSubgroup.mem_rightTransversals_iff_existsUnique_quotient_mk''_eq
@[to_additive]
theorem mem_leftTransversals_iff_bijective :
S ∈ leftTransversals (H : Set G) ↔
Function.Bijective (S.restrict (Quotient.mk'' : G → Quotient (QuotientGroup.leftRel H))) :=
mem_leftTransversals_iff_existsUnique_quotient_mk''_eq.trans
(Function.bijective_iff_existsUnique (S.restrict Quotient.mk'')).symm
#align subgroup.mem_left_transversals_iff_bijective Subgroup.mem_leftTransversals_iff_bijective
#align add_subgroup.mem_left_transversals_iff_bijective AddSubgroup.mem_leftTransversals_iff_bijective
@[to_additive]
theorem mem_rightTransversals_iff_bijective :
S ∈ rightTransversals (H : Set G) ↔
Function.Bijective (S.restrict (Quotient.mk'' : G → Quotient (QuotientGroup.rightRel H))) :=
mem_rightTransversals_iff_existsUnique_quotient_mk''_eq.trans
(Function.bijective_iff_existsUnique (S.restrict Quotient.mk'')).symm
#align subgroup.mem_right_transversals_iff_bijective Subgroup.mem_rightTransversals_iff_bijective
#align add_subgroup.mem_right_transversals_iff_bijective AddSubgroup.mem_rightTransversals_iff_bijective
@[to_additive]
theorem card_left_transversal (h : S ∈ leftTransversals (H : Set G)) : Nat.card S = H.index :=
Nat.card_congr <| Equiv.ofBijective _ <| mem_leftTransversals_iff_bijective.mp h
#align subgroup.card_left_transversal Subgroup.card_left_transversal
#align add_subgroup.card_left_transversal AddSubgroup.card_left_transversal
@[to_additive]
theorem card_right_transversal (h : S ∈ rightTransversals (H : Set G)) : Nat.card S = H.index :=
Nat.card_congr <|
(Equiv.ofBijective _ <| mem_rightTransversals_iff_bijective.mp h).trans <|
QuotientGroup.quotientRightRelEquivQuotientLeftRel H
#align subgroup.card_right_transversal Subgroup.card_right_transversal
#align add_subgroup.card_right_transversal AddSubgroup.card_right_transversal
@[to_additive]
theorem range_mem_leftTransversals {f : G ⧸ H → G} (hf : ∀ q, ↑(f q) = q) :
Set.range f ∈ leftTransversals (H : Set G) :=
mem_leftTransversals_iff_bijective.mpr
⟨by rintro ⟨-, q₁, rfl⟩ ⟨-, q₂, rfl⟩ h
exact Subtype.ext <| congr_arg f <| ((hf q₁).symm.trans h).trans (hf q₂),
fun q => ⟨⟨f q, q, rfl⟩, hf q⟩⟩
#align subgroup.range_mem_left_transversals Subgroup.range_mem_leftTransversals
#align add_subgroup.range_mem_left_transversals AddSubgroup.range_mem_leftTransversals
@[to_additive]
theorem range_mem_rightTransversals {f : Quotient (QuotientGroup.rightRel H) → G}
(hf : ∀ q, Quotient.mk'' (f q) = q) : Set.range f ∈ rightTransversals (H : Set G) :=
mem_rightTransversals_iff_bijective.mpr
⟨by rintro ⟨-, q₁, rfl⟩ ⟨-, q₂, rfl⟩ h
exact Subtype.ext <| congr_arg f <| ((hf q₁).symm.trans h).trans (hf q₂),
fun q => ⟨⟨f q, q, rfl⟩, hf q⟩⟩
#align subgroup.range_mem_right_transversals Subgroup.range_mem_rightTransversals
#align add_subgroup.range_mem_right_transversals AddSubgroup.range_mem_rightTransversals
@[to_additive]
lemma exists_left_transversal (H : Subgroup G) (g : G) :
∃ S ∈ leftTransversals (H : Set G), g ∈ S := by
classical
refine
⟨Set.range (Function.update Quotient.out' _ g), range_mem_leftTransversals fun q => ?_,
Quotient.mk'' g, Function.update_same (Quotient.mk'' g) g Quotient.out'⟩
by_cases hq : q = Quotient.mk'' g
· exact hq.symm ▸ congr_arg _ (Function.update_same (Quotient.mk'' g) g Quotient.out')
· refine (Function.update_noteq ?_ g Quotient.out') ▸ q.out_eq'
exact hq
#align subgroup.exists_left_transversal Subgroup.exists_left_transversal
#align add_subgroup.exists_left_transversal AddSubgroup.exists_left_transversal
@[to_additive]
lemma exists_right_transversal (H : Subgroup G) (g : G) :
∃ S ∈ rightTransversals (H : Set G), g ∈ S := by
classical
refine
⟨Set.range (Function.update Quotient.out' _ g), range_mem_rightTransversals fun q => ?_,
Quotient.mk'' g, Function.update_same (Quotient.mk'' g) g Quotient.out'⟩
by_cases hq : q = Quotient.mk'' g
· exact hq.symm ▸ congr_arg _ (Function.update_same (Quotient.mk'' g) g Quotient.out')
· exact Eq.trans (congr_arg _ (Function.update_noteq hq g Quotient.out')) q.out_eq'
#align subgroup.exists_right_transversal Subgroup.exists_right_transversal
#align add_subgroup.exists_right_transversal AddSubgroup.exists_right_transversal
@[to_additive "Given two subgroups `H' ⊆ H`, there exists a transversal to `H'` inside `H`"]
lemma exists_left_transversal_of_le {H' H : Subgroup G} (h : H' ≤ H) :
∃ S : Set G, S * H' = H ∧ Nat.card S * Nat.card H' = Nat.card H := by
let H'' : Subgroup H := H'.comap H.subtype
have : H' = H''.map H.subtype := by simp [H'', h]
rw [this]
obtain ⟨S, cmem, -⟩ := H''.exists_left_transversal 1
refine ⟨H.subtype '' S, ?_, ?_⟩
· have : H.subtype '' (S * H'') = H.subtype '' S * H''.map H.subtype := image_mul H.subtype
rw [← this, cmem.mul_eq]
simp [Set.ext_iff]
· rw [← cmem.card_mul_card]
refine congr_arg₂ (· * ·) ?_ ?_ <;>
exact Nat.card_congr (Equiv.Set.image _ _ <| subtype_injective H).symm
@[to_additive "Given two subgroups `H' ⊆ H`, there exists a transversal to `H'` inside `H`"]
lemma exists_right_transversal_of_le {H' H : Subgroup G} (h : H' ≤ H) :
∃ S : Set G, H' * S = H ∧ Nat.card H' * Nat.card S = Nat.card H := by
let H'' : Subgroup H := H'.comap H.subtype
have : H' = H''.map H.subtype := by simp [H'', h]
rw [this]
obtain ⟨S, cmem, -⟩ := H''.exists_right_transversal 1
refine ⟨H.subtype '' S, ?_, ?_⟩
· have : H.subtype '' (H'' * S) = H''.map H.subtype * H.subtype '' S := image_mul H.subtype
rw [← this, cmem.mul_eq]
simp [Set.ext_iff]
· have : Nat.card H'' * Nat.card S = Nat.card H := cmem.card_mul_card
rw [← this]
refine congr_arg₂ (· * ·) ?_ ?_ <;>
exact Nat.card_congr (Equiv.Set.image _ _ <| subtype_injective H).symm
namespace IsComplement
noncomputable def equiv {S T : Set G} (hST : IsComplement S T) : G ≃ S × T :=
(Equiv.ofBijective (fun x : S × T => x.1.1 * x.2.1) hST).symm
variable (hST : IsComplement S T) (hHT : IsComplement H T) (hSK : IsComplement S K)
@[simp] theorem equiv_symm_apply (x : S × T) : (hST.equiv.symm x : G) = x.1.1 * x.2.1 := rfl
@[simp]
theorem equiv_fst_mul_equiv_snd (g : G) : ↑(hST.equiv g).fst * (hST.equiv g).snd = g :=
(Equiv.ofBijective (fun x : S × T => x.1.1 * x.2.1) hST).right_inv g
theorem equiv_fst_eq_mul_inv (g : G) : ↑(hST.equiv g).fst = g * ((hST.equiv g).snd : G)⁻¹ :=
eq_mul_inv_of_mul_eq (hST.equiv_fst_mul_equiv_snd g)
theorem equiv_snd_eq_inv_mul (g : G) : ↑(hST.equiv g).snd = ((hST.equiv g).fst : G)⁻¹ * g :=
eq_inv_mul_of_mul_eq (hST.equiv_fst_mul_equiv_snd g)
theorem equiv_fst_eq_iff_leftCosetEquivalence {g₁ g₂ : G} :
(hSK.equiv g₁).fst = (hSK.equiv g₂).fst ↔ LeftCosetEquivalence K g₁ g₂ := by
rw [LeftCosetEquivalence, leftCoset_eq_iff]
constructor
· intro h
rw [← hSK.equiv_fst_mul_equiv_snd g₂, ← hSK.equiv_fst_mul_equiv_snd g₁, ← h,
mul_inv_rev, ← mul_assoc, inv_mul_cancel_right, ← coe_inv, ← coe_mul]
exact Subtype.property _
· intro h
apply (mem_leftTransversals_iff_existsUnique_inv_mul_mem.1 hSK g₁).unique
· -- This used to be `simp [...]` before leanprover/lean4#2644
rw [equiv_fst_eq_mul_inv]; simp
· rw [SetLike.mem_coe, ← mul_mem_cancel_right h]
-- This used to be `simp [...]` before leanprover/lean4#2644
rw [equiv_fst_eq_mul_inv]; simp [equiv_fst_eq_mul_inv, ← mul_assoc]
theorem equiv_snd_eq_iff_rightCosetEquivalence {g₁ g₂ : G} :
(hHT.equiv g₁).snd = (hHT.equiv g₂).snd ↔ RightCosetEquivalence H g₁ g₂ := by
rw [RightCosetEquivalence, rightCoset_eq_iff]
constructor
· intro h
rw [← hHT.equiv_fst_mul_equiv_snd g₂, ← hHT.equiv_fst_mul_equiv_snd g₁, ← h,
mul_inv_rev, mul_assoc, mul_inv_cancel_left, ← coe_inv, ← coe_mul]
exact Subtype.property _
· intro h
apply (mem_rightTransversals_iff_existsUnique_mul_inv_mem.1 hHT g₁).unique
· -- This used to be `simp [...]` before leanprover/lean4#2644
rw [equiv_snd_eq_inv_mul]; simp
· rw [SetLike.mem_coe, ← mul_mem_cancel_left h]
-- This used to be `simp [...]` before leanprover/lean4#2644
rw [equiv_snd_eq_inv_mul, mul_assoc]; simp
theorem leftCosetEquivalence_equiv_fst (g : G) :
LeftCosetEquivalence K g ((hSK.equiv g).fst : G) := by
-- This used to be `simp [...]` before leanprover/lean4#2644
rw [equiv_fst_eq_mul_inv]; simp [LeftCosetEquivalence, leftCoset_eq_iff]
| Mathlib/GroupTheory/Complement.lean | 436 | 439 | theorem rightCosetEquivalence_equiv_snd (g : G) :
RightCosetEquivalence H g ((hHT.equiv g).snd : G) := by |
-- This used to be `simp [...]` before leanprover/lean4#2644
rw [RightCosetEquivalence, rightCoset_eq_iff, equiv_snd_eq_inv_mul]; simp
|
import Mathlib.Data.Set.Image
#align_import order.directed from "leanprover-community/mathlib"@"ffde2d8a6e689149e44fd95fa862c23a57f8c780"
open Function
universe u v w
variable {α : Type u} {β : Type v} {ι : Sort w} (r r' s : α → α → Prop)
local infixl:50 " ≼ " => r
def Directed (f : ι → α) :=
∀ x y, ∃ z, f x ≼ f z ∧ f y ≼ f z
#align directed Directed
def DirectedOn (s : Set α) :=
∀ x ∈ s, ∀ y ∈ s, ∃ z ∈ s, x ≼ z ∧ y ≼ z
#align directed_on DirectedOn
variable {r r'}
| Mathlib/Order/Directed.lean | 58 | 60 | theorem directedOn_iff_directed {s} : @DirectedOn α r s ↔ Directed r (Subtype.val : s → α) := by |
simp only [DirectedOn, Directed, Subtype.exists, exists_and_left, exists_prop, Subtype.forall]
exact forall₂_congr fun x _ => by simp [And.comm, and_assoc]
|
import Mathlib.LinearAlgebra.AffineSpace.AffineEquiv
#align_import linear_algebra.affine_space.midpoint from "leanprover-community/mathlib"@"2196ab363eb097c008d4497125e0dde23fb36db2"
open AffineMap AffineEquiv
section
variable (R : Type*) {V V' P P' : Type*} [Ring R] [Invertible (2 : R)] [AddCommGroup V]
[Module R V] [AddTorsor V P] [AddCommGroup V'] [Module R V'] [AddTorsor V' P']
def midpoint (x y : P) : P :=
lineMap x y (⅟ 2 : R)
#align midpoint midpoint
variable {R} {x y z : P}
@[simp]
theorem AffineMap.map_midpoint (f : P →ᵃ[R] P') (a b : P) :
f (midpoint R a b) = midpoint R (f a) (f b) :=
f.apply_lineMap a b _
#align affine_map.map_midpoint AffineMap.map_midpoint
@[simp]
theorem AffineEquiv.map_midpoint (f : P ≃ᵃ[R] P') (a b : P) :
f (midpoint R a b) = midpoint R (f a) (f b) :=
f.apply_lineMap a b _
#align affine_equiv.map_midpoint AffineEquiv.map_midpoint
theorem AffineEquiv.pointReflection_midpoint_left (x y : P) :
pointReflection R (midpoint R x y) x = y := by
rw [midpoint, pointReflection_apply, lineMap_apply, vadd_vsub, vadd_vadd, ← add_smul, ← two_mul,
mul_invOf_self, one_smul, vsub_vadd]
#align affine_equiv.point_reflection_midpoint_left AffineEquiv.pointReflection_midpoint_left
@[simp] -- Porting note: added variant with `Equiv.pointReflection` for `simp`
theorem Equiv.pointReflection_midpoint_left (x y : P) :
(Equiv.pointReflection (midpoint R x y)) x = y := by
rw [midpoint, pointReflection_apply, lineMap_apply, vadd_vsub, vadd_vadd, ← add_smul, ← two_mul,
mul_invOf_self, one_smul, vsub_vadd]
theorem midpoint_comm (x y : P) : midpoint R x y = midpoint R y x := by
rw [midpoint, ← lineMap_apply_one_sub, one_sub_invOf_two, midpoint]
#align midpoint_comm midpoint_comm
| Mathlib/LinearAlgebra/AffineSpace/Midpoint.lean | 77 | 79 | theorem AffineEquiv.pointReflection_midpoint_right (x y : P) :
pointReflection R (midpoint R x y) y = x := by |
rw [midpoint_comm, AffineEquiv.pointReflection_midpoint_left]
|
import Mathlib.Tactic.NormNum.Inv
set_option autoImplicit true
open Lean Meta Qq
namespace Mathlib.Meta.NormNum
theorem isNat_eq_false [AddMonoidWithOne α] [CharZero α] : {a b : α} → {a' b' : ℕ} →
IsNat a a' → IsNat b b' → Nat.beq a' b' = false → ¬a = b
| _, _, _, _, ⟨rfl⟩, ⟨rfl⟩, h => by simp; exact Nat.ne_of_beq_eq_false h
theorem isInt_eq_false [Ring α] [CharZero α] : {a b : α} → {a' b' : ℤ} →
IsInt a a' → IsInt b b' → decide (a' = b') = false → ¬a = b
| _, _, _, _, ⟨rfl⟩, ⟨rfl⟩, h => by simp; exact of_decide_eq_false h
| Mathlib/Tactic/NormNum/Eq.lean | 26 | 29 | theorem Rat.invOf_denom_swap [Ring α] (n₁ n₂ : ℤ) (a₁ a₂ : α)
[Invertible a₁] [Invertible a₂] : n₁ * ⅟a₁ = n₂ * ⅟a₂ ↔ n₁ * a₂ = n₂ * a₁ := by |
rw [mul_invOf_eq_iff_eq_mul_right, ← Int.commute_cast, mul_assoc,
← mul_left_eq_iff_eq_invOf_mul, Int.commute_cast]
|
import Mathlib.RingTheory.EisensteinCriterion
import Mathlib.RingTheory.Polynomial.ScaleRoots
#align_import ring_theory.polynomial.eisenstein.basic from "leanprover-community/mathlib"@"2032a878972d5672e7c27c957e7a6e297b044973"
universe u v w z
variable {R : Type u}
open Ideal Algebra Finset
open Polynomial
namespace Polynomial
@[mk_iff]
structure IsWeaklyEisensteinAt [CommSemiring R] (f : R[X]) (𝓟 : Ideal R) : Prop where
mem : ∀ {n}, n < f.natDegree → f.coeff n ∈ 𝓟
#align polynomial.is_weakly_eisenstein_at Polynomial.IsWeaklyEisensteinAt
@[mk_iff]
structure IsEisensteinAt [CommSemiring R] (f : R[X]) (𝓟 : Ideal R) : Prop where
leading : f.leadingCoeff ∉ 𝓟
mem : ∀ {n}, n < f.natDegree → f.coeff n ∈ 𝓟
not_mem : f.coeff 0 ∉ 𝓟 ^ 2
#align polynomial.is_eisenstein_at Polynomial.IsEisensteinAt
namespace IsWeaklyEisensteinAt
section CommSemiring
variable [CommSemiring R] {𝓟 : Ideal R} {f : R[X]} (hf : f.IsWeaklyEisensteinAt 𝓟)
| Mathlib/RingTheory/Polynomial/Eisenstein/Basic.lean | 66 | 69 | theorem map {A : Type v} [CommRing A] (φ : R →+* A) : (f.map φ).IsWeaklyEisensteinAt (𝓟.map φ) := by |
refine (isWeaklyEisensteinAt_iff _ _).2 fun hn => ?_
rw [coeff_map]
exact mem_map_of_mem _ (hf.mem (lt_of_lt_of_le hn (natDegree_map_le _ _)))
|
import Mathlib.Data.Set.Subsingleton
import Mathlib.Logic.Equiv.Defs
import Mathlib.Algebra.Group.Defs
#align_import data.part from "leanprover-community/mathlib"@"80c43012d26f63026d362c3aba28f3c3bafb07e6"
open Function
structure Part.{u} (α : Type u) : Type u where
Dom : Prop
get : Dom → α
#align part Part
namespace Part
variable {α : Type*} {β : Type*} {γ : Type*}
def toOption (o : Part α) [Decidable o.Dom] : Option α :=
if h : Dom o then some (o.get h) else none
#align part.to_option Part.toOption
@[simp] lemma toOption_isSome (o : Part α) [Decidable o.Dom] : o.toOption.isSome ↔ o.Dom := by
by_cases h : o.Dom <;> simp [h, toOption]
#align part.to_option_is_some Part.toOption_isSome
@[simp] lemma toOption_isNone (o : Part α) [Decidable o.Dom] : o.toOption.isNone ↔ ¬o.Dom := by
by_cases h : o.Dom <;> simp [h, toOption]
#align part.to_option_is_none Part.toOption_isNone
theorem ext' : ∀ {o p : Part α}, (o.Dom ↔ p.Dom) → (∀ h₁ h₂, o.get h₁ = p.get h₂) → o = p
| ⟨od, o⟩, ⟨pd, p⟩, H1, H2 => by
have t : od = pd := propext H1
cases t; rw [show o = p from funext fun p => H2 p p]
#align part.ext' Part.ext'
@[simp]
theorem eta : ∀ o : Part α, (⟨o.Dom, fun h => o.get h⟩ : Part α) = o
| ⟨_, _⟩ => rfl
#align part.eta Part.eta
protected def Mem (a : α) (o : Part α) : Prop :=
∃ h, o.get h = a
#align part.mem Part.Mem
instance : Membership α (Part α) :=
⟨Part.Mem⟩
theorem mem_eq (a : α) (o : Part α) : (a ∈ o) = ∃ h, o.get h = a :=
rfl
#align part.mem_eq Part.mem_eq
theorem dom_iff_mem : ∀ {o : Part α}, o.Dom ↔ ∃ y, y ∈ o
| ⟨_, f⟩ => ⟨fun h => ⟨f h, h, rfl⟩, fun ⟨_, h, rfl⟩ => h⟩
#align part.dom_iff_mem Part.dom_iff_mem
theorem get_mem {o : Part α} (h) : get o h ∈ o :=
⟨_, rfl⟩
#align part.get_mem Part.get_mem
@[simp]
theorem mem_mk_iff {p : Prop} {o : p → α} {a : α} : a ∈ Part.mk p o ↔ ∃ h, o h = a :=
Iff.rfl
#align part.mem_mk_iff Part.mem_mk_iff
@[ext]
theorem ext {o p : Part α} (H : ∀ a, a ∈ o ↔ a ∈ p) : o = p :=
(ext' ⟨fun h => ((H _).1 ⟨h, rfl⟩).fst, fun h => ((H _).2 ⟨h, rfl⟩).fst⟩) fun _ _ =>
((H _).2 ⟨_, rfl⟩).snd
#align part.ext Part.ext
def none : Part α :=
⟨False, False.rec⟩
#align part.none Part.none
instance : Inhabited (Part α) :=
⟨none⟩
@[simp]
theorem not_mem_none (a : α) : a ∉ @none α := fun h => h.fst
#align part.not_mem_none Part.not_mem_none
def some (a : α) : Part α :=
⟨True, fun _ => a⟩
#align part.some Part.some
@[simp]
theorem some_dom (a : α) : (some a).Dom :=
trivial
#align part.some_dom Part.some_dom
theorem mem_unique : ∀ {a b : α} {o : Part α}, a ∈ o → b ∈ o → a = b
| _, _, ⟨_, _⟩, ⟨_, rfl⟩, ⟨_, rfl⟩ => rfl
#align part.mem_unique Part.mem_unique
theorem Mem.left_unique : Relator.LeftUnique ((· ∈ ·) : α → Part α → Prop) := fun _ _ _ =>
mem_unique
#align part.mem.left_unique Part.Mem.left_unique
theorem get_eq_of_mem {o : Part α} {a} (h : a ∈ o) (h') : get o h' = a :=
mem_unique ⟨_, rfl⟩ h
#align part.get_eq_of_mem Part.get_eq_of_mem
protected theorem subsingleton (o : Part α) : Set.Subsingleton { a | a ∈ o } := fun _ ha _ hb =>
mem_unique ha hb
#align part.subsingleton Part.subsingleton
@[simp]
theorem get_some {a : α} (ha : (some a).Dom) : get (some a) ha = a :=
rfl
#align part.get_some Part.get_some
theorem mem_some (a : α) : a ∈ some a :=
⟨trivial, rfl⟩
#align part.mem_some Part.mem_some
@[simp]
theorem mem_some_iff {a b} : b ∈ (some a : Part α) ↔ b = a :=
⟨fun ⟨_, e⟩ => e.symm, fun e => ⟨trivial, e.symm⟩⟩
#align part.mem_some_iff Part.mem_some_iff
theorem eq_some_iff {a : α} {o : Part α} : o = some a ↔ a ∈ o :=
⟨fun e => e.symm ▸ mem_some _, fun ⟨h, e⟩ => e ▸ ext' (iff_true_intro h) fun _ _ => rfl⟩
#align part.eq_some_iff Part.eq_some_iff
theorem eq_none_iff {o : Part α} : o = none ↔ ∀ a, a ∉ o :=
⟨fun e => e.symm ▸ not_mem_none, fun h => ext (by simpa)⟩
#align part.eq_none_iff Part.eq_none_iff
theorem eq_none_iff' {o : Part α} : o = none ↔ ¬o.Dom :=
⟨fun e => e.symm ▸ id, fun h => eq_none_iff.2 fun _ h' => h h'.fst⟩
#align part.eq_none_iff' Part.eq_none_iff'
@[simp]
theorem not_none_dom : ¬(none : Part α).Dom :=
id
#align part.not_none_dom Part.not_none_dom
@[simp]
theorem some_ne_none (x : α) : some x ≠ none := by
intro h
exact true_ne_false (congr_arg Dom h)
#align part.some_ne_none Part.some_ne_none
@[simp]
theorem none_ne_some (x : α) : none ≠ some x :=
(some_ne_none x).symm
#align part.none_ne_some Part.none_ne_some
theorem ne_none_iff {o : Part α} : o ≠ none ↔ ∃ x, o = some x := by
constructor
· rw [Ne, eq_none_iff', not_not]
exact fun h => ⟨o.get h, eq_some_iff.2 (get_mem h)⟩
· rintro ⟨x, rfl⟩
apply some_ne_none
#align part.ne_none_iff Part.ne_none_iff
theorem eq_none_or_eq_some (o : Part α) : o = none ∨ ∃ x, o = some x :=
or_iff_not_imp_left.2 ne_none_iff.1
#align part.eq_none_or_eq_some Part.eq_none_or_eq_some
theorem some_injective : Injective (@Part.some α) := fun _ _ h =>
congr_fun (eq_of_heq (Part.mk.inj h).2) trivial
#align part.some_injective Part.some_injective
@[simp]
theorem some_inj {a b : α} : Part.some a = some b ↔ a = b :=
some_injective.eq_iff
#align part.some_inj Part.some_inj
@[simp]
theorem some_get {a : Part α} (ha : a.Dom) : Part.some (Part.get a ha) = a :=
Eq.symm (eq_some_iff.2 ⟨ha, rfl⟩)
#align part.some_get Part.some_get
theorem get_eq_iff_eq_some {a : Part α} {ha : a.Dom} {b : α} : a.get ha = b ↔ a = some b :=
⟨fun h => by simp [h.symm], fun h => by simp [h]⟩
#align part.get_eq_iff_eq_some Part.get_eq_iff_eq_some
theorem get_eq_get_of_eq (a : Part α) (ha : a.Dom) {b : Part α} (h : a = b) :
a.get ha = b.get (h ▸ ha) := by
congr
#align part.get_eq_get_of_eq Part.get_eq_get_of_eq
theorem get_eq_iff_mem {o : Part α} {a : α} (h : o.Dom) : o.get h = a ↔ a ∈ o :=
⟨fun H => ⟨h, H⟩, fun ⟨_, H⟩ => H⟩
#align part.get_eq_iff_mem Part.get_eq_iff_mem
theorem eq_get_iff_mem {o : Part α} {a : α} (h : o.Dom) : a = o.get h ↔ a ∈ o :=
eq_comm.trans (get_eq_iff_mem h)
#align part.eq_get_iff_mem Part.eq_get_iff_mem
@[simp]
theorem none_toOption [Decidable (@none α).Dom] : (none : Part α).toOption = Option.none :=
dif_neg id
#align part.none_to_option Part.none_toOption
@[simp]
theorem some_toOption (a : α) [Decidable (some a).Dom] : (some a).toOption = Option.some a :=
dif_pos trivial
#align part.some_to_option Part.some_toOption
instance noneDecidable : Decidable (@none α).Dom :=
instDecidableFalse
#align part.none_decidable Part.noneDecidable
instance someDecidable (a : α) : Decidable (some a).Dom :=
instDecidableTrue
#align part.some_decidable Part.someDecidable
def getOrElse (a : Part α) [Decidable a.Dom] (d : α) :=
if ha : a.Dom then a.get ha else d
#align part.get_or_else Part.getOrElse
theorem getOrElse_of_dom (a : Part α) (h : a.Dom) [Decidable a.Dom] (d : α) :
getOrElse a d = a.get h :=
dif_pos h
#align part.get_or_else_of_dom Part.getOrElse_of_dom
theorem getOrElse_of_not_dom (a : Part α) (h : ¬a.Dom) [Decidable a.Dom] (d : α) :
getOrElse a d = d :=
dif_neg h
#align part.get_or_else_of_not_dom Part.getOrElse_of_not_dom
@[simp]
theorem getOrElse_none (d : α) [Decidable (none : Part α).Dom] : getOrElse none d = d :=
none.getOrElse_of_not_dom not_none_dom d
#align part.get_or_else_none Part.getOrElse_none
@[simp]
theorem getOrElse_some (a : α) (d : α) [Decidable (some a).Dom] : getOrElse (some a) d = a :=
(some a).getOrElse_of_dom (some_dom a) d
#align part.get_or_else_some Part.getOrElse_some
-- Porting note: removed `simp`
theorem mem_toOption {o : Part α} [Decidable o.Dom] {a : α} : a ∈ toOption o ↔ a ∈ o := by
unfold toOption
by_cases h : o.Dom <;> simp [h]
· exact ⟨fun h => ⟨_, h⟩, fun ⟨_, h⟩ => h⟩
· exact mt Exists.fst h
#align part.mem_to_option Part.mem_toOption
-- Porting note (#10756): new theorem, like `mem_toOption` but with LHS in `simp` normal form
@[simp]
theorem toOption_eq_some_iff {o : Part α} [Decidable o.Dom] {a : α} :
toOption o = Option.some a ↔ a ∈ o := by
rw [← Option.mem_def, mem_toOption]
protected theorem Dom.toOption {o : Part α} [Decidable o.Dom] (h : o.Dom) : o.toOption = o.get h :=
dif_pos h
#align part.dom.to_option Part.Dom.toOption
theorem toOption_eq_none_iff {a : Part α} [Decidable a.Dom] : a.toOption = Option.none ↔ ¬a.Dom :=
Ne.dite_eq_right_iff fun _ => Option.some_ne_none _
#align part.to_option_eq_none_iff Part.toOption_eq_none_iff
theorem elim_toOption {α β : Type*} (a : Part α) [Decidable a.Dom] (b : β) (f : α → β) :
a.toOption.elim b f = if h : a.Dom then f (a.get h) else b := by
split_ifs with h
· rw [h.toOption]
rfl
· rw [Part.toOption_eq_none_iff.2 h]
rfl
#align part.elim_to_option Part.elim_toOption
@[coe]
def ofOption : Option α → Part α
| Option.none => none
| Option.some a => some a
#align part.of_option Part.ofOption
@[simp]
theorem mem_ofOption {a : α} : ∀ {o : Option α}, a ∈ ofOption o ↔ a ∈ o
| Option.none => ⟨fun h => h.fst.elim, fun h => Option.noConfusion h⟩
| Option.some _ => ⟨fun h => congr_arg Option.some h.snd, fun h => ⟨trivial, Option.some.inj h⟩⟩
#align part.mem_of_option Part.mem_ofOption
@[simp]
theorem ofOption_dom {α} : ∀ o : Option α, (ofOption o).Dom ↔ o.isSome
| Option.none => by simp [ofOption, none]
| Option.some a => by simp [ofOption]
#align part.of_option_dom Part.ofOption_dom
theorem ofOption_eq_get {α} (o : Option α) : ofOption o = ⟨_, @Option.get _ o⟩ :=
Part.ext' (ofOption_dom o) fun h₁ h₂ => by
cases o
· simp at h₂
· rfl
#align part.of_option_eq_get Part.ofOption_eq_get
instance : Coe (Option α) (Part α) :=
⟨ofOption⟩
theorem mem_coe {a : α} {o : Option α} : a ∈ (o : Part α) ↔ a ∈ o :=
mem_ofOption
#align part.mem_coe Part.mem_coe
@[simp]
theorem coe_none : (@Option.none α : Part α) = none :=
rfl
#align part.coe_none Part.coe_none
@[simp]
theorem coe_some (a : α) : (Option.some a : Part α) = some a :=
rfl
#align part.coe_some Part.coe_some
@[elab_as_elim]
protected theorem induction_on {P : Part α → Prop} (a : Part α) (hnone : P none)
(hsome : ∀ a : α, P (some a)) : P a :=
(Classical.em a.Dom).elim (fun h => Part.some_get h ▸ hsome _) fun h =>
(eq_none_iff'.2 h).symm ▸ hnone
#align part.induction_on Part.induction_on
instance ofOptionDecidable : ∀ o : Option α, Decidable (ofOption o).Dom
| Option.none => Part.noneDecidable
| Option.some a => Part.someDecidable a
#align part.of_option_decidable Part.ofOptionDecidable
@[simp]
theorem to_ofOption (o : Option α) : toOption (ofOption o) = o := by cases o <;> rfl
#align part.to_of_option Part.to_ofOption
@[simp]
theorem of_toOption (o : Part α) [Decidable o.Dom] : ofOption (toOption o) = o :=
ext fun _ => mem_ofOption.trans mem_toOption
#align part.of_to_option Part.of_toOption
noncomputable def equivOption : Part α ≃ Option α :=
haveI := Classical.dec
⟨fun o => toOption o, ofOption, fun o => of_toOption o, fun o =>
Eq.trans (by dsimp; congr) (to_ofOption o)⟩
#align part.equiv_option Part.equivOption
instance : PartialOrder (Part
α) where
le x y := ∀ i, i ∈ x → i ∈ y
le_refl x y := id
le_trans x y z f g i := g _ ∘ f _
le_antisymm x y f g := Part.ext fun z => ⟨f _, g _⟩
instance : OrderBot (Part α) where
bot := none
bot_le := by rintro x _ ⟨⟨_⟩, _⟩
theorem le_total_of_le_of_le {x y : Part α} (z : Part α) (hx : x ≤ z) (hy : y ≤ z) :
x ≤ y ∨ y ≤ x := by
rcases Part.eq_none_or_eq_some x with (h | ⟨b, h₀⟩)
· rw [h]
left
apply OrderBot.bot_le _
right; intro b' h₁
rw [Part.eq_some_iff] at h₀
have hx := hx _ h₀; have hy := hy _ h₁
have hx := Part.mem_unique hx hy; subst hx
exact h₀
#align part.le_total_of_le_of_le Part.le_total_of_le_of_le
def assert (p : Prop) (f : p → Part α) : Part α :=
⟨∃ h : p, (f h).Dom, fun ha => (f ha.fst).get ha.snd⟩
#align part.assert Part.assert
protected def bind (f : Part α) (g : α → Part β) : Part β :=
assert (Dom f) fun b => g (f.get b)
#align part.bind Part.bind
@[simps]
def map (f : α → β) (o : Part α) : Part β :=
⟨o.Dom, f ∘ o.get⟩
#align part.map Part.map
#align part.map_dom Part.map_Dom
#align part.map_get Part.map_get
theorem mem_map (f : α → β) {o : Part α} : ∀ {a}, a ∈ o → f a ∈ map f o
| _, ⟨_, rfl⟩ => ⟨_, rfl⟩
#align part.mem_map Part.mem_map
@[simp]
theorem mem_map_iff (f : α → β) {o : Part α} {b} : b ∈ map f o ↔ ∃ a ∈ o, f a = b :=
⟨fun hb => match b, hb with
| _, ⟨_, rfl⟩ => ⟨_, ⟨_, rfl⟩, rfl⟩,
fun ⟨_, h₁, h₂⟩ => h₂ ▸ mem_map f h₁⟩
#align part.mem_map_iff Part.mem_map_iff
@[simp]
theorem map_none (f : α → β) : map f none = none :=
eq_none_iff.2 fun a => by simp
#align part.map_none Part.map_none
@[simp]
theorem map_some (f : α → β) (a : α) : map f (some a) = some (f a) :=
eq_some_iff.2 <| mem_map f <| mem_some _
#align part.map_some Part.map_some
theorem mem_assert {p : Prop} {f : p → Part α} : ∀ {a} (h : p), a ∈ f h → a ∈ assert p f
| _, x, ⟨h, rfl⟩ => ⟨⟨x, h⟩, rfl⟩
#align part.mem_assert Part.mem_assert
@[simp]
theorem mem_assert_iff {p : Prop} {f : p → Part α} {a} : a ∈ assert p f ↔ ∃ h : p, a ∈ f h :=
⟨fun ha => match a, ha with
| _, ⟨_, rfl⟩ => ⟨_, ⟨_, rfl⟩⟩,
fun ⟨_, h⟩ => mem_assert _ h⟩
#align part.mem_assert_iff Part.mem_assert_iff
theorem assert_pos {p : Prop} {f : p → Part α} (h : p) : assert p f = f h := by
dsimp [assert]
cases h' : f h
simp only [h', mk.injEq, h, exists_prop_of_true, true_and]
apply Function.hfunext
· simp only [h, h', exists_prop_of_true]
· aesop
#align part.assert_pos Part.assert_pos
theorem assert_neg {p : Prop} {f : p → Part α} (h : ¬p) : assert p f = none := by
dsimp [assert, none]; congr
· simp only [h, not_false_iff, exists_prop_of_false]
· apply Function.hfunext
· simp only [h, not_false_iff, exists_prop_of_false]
simp at *
#align part.assert_neg Part.assert_neg
theorem mem_bind {f : Part α} {g : α → Part β} : ∀ {a b}, a ∈ f → b ∈ g a → b ∈ f.bind g
| _, _, ⟨h, rfl⟩, ⟨h₂, rfl⟩ => ⟨⟨h, h₂⟩, rfl⟩
#align part.mem_bind Part.mem_bind
@[simp]
theorem mem_bind_iff {f : Part α} {g : α → Part β} {b} : b ∈ f.bind g ↔ ∃ a ∈ f, b ∈ g a :=
⟨fun hb => match b, hb with
| _, ⟨⟨_, _⟩, rfl⟩ => ⟨_, ⟨_, rfl⟩, ⟨_, rfl⟩⟩,
fun ⟨_, h₁, h₂⟩ => mem_bind h₁ h₂⟩
#align part.mem_bind_iff Part.mem_bind_iff
protected theorem Dom.bind {o : Part α} (h : o.Dom) (f : α → Part β) : o.bind f = f (o.get h) := by
ext b
simp only [Part.mem_bind_iff, exists_prop]
refine ⟨?_, fun hb => ⟨o.get h, Part.get_mem _, hb⟩⟩
rintro ⟨a, ha, hb⟩
rwa [Part.get_eq_of_mem ha]
#align part.dom.bind Part.Dom.bind
theorem Dom.of_bind {f : α → Part β} {a : Part α} (h : (a.bind f).Dom) : a.Dom :=
h.1
#align part.dom.of_bind Part.Dom.of_bind
@[simp]
theorem bind_none (f : α → Part β) : none.bind f = none :=
eq_none_iff.2 fun a => by simp
#align part.bind_none Part.bind_none
@[simp]
theorem bind_some (a : α) (f : α → Part β) : (some a).bind f = f a :=
ext <| by simp
#align part.bind_some Part.bind_some
theorem bind_of_mem {o : Part α} {a : α} (h : a ∈ o) (f : α → Part β) : o.bind f = f a := by
rw [eq_some_iff.2 h, bind_some]
#align part.bind_of_mem Part.bind_of_mem
theorem bind_some_eq_map (f : α → β) (x : Part α) : x.bind (some ∘ f) = map f x :=
ext <| by simp [eq_comm]
#align part.bind_some_eq_map Part.bind_some_eq_map
theorem bind_toOption (f : α → Part β) (o : Part α) [Decidable o.Dom] [∀ a, Decidable (f a).Dom]
[Decidable (o.bind f).Dom] :
(o.bind f).toOption = o.toOption.elim Option.none fun a => (f a).toOption := by
by_cases h : o.Dom
· simp_rw [h.toOption, h.bind]
rfl
· rw [Part.toOption_eq_none_iff.2 h]
exact Part.toOption_eq_none_iff.2 fun ho => h ho.of_bind
#align part.bind_to_option Part.bind_toOption
theorem bind_assoc {γ} (f : Part α) (g : α → Part β) (k : β → Part γ) :
(f.bind g).bind k = f.bind fun x => (g x).bind k :=
ext fun a => by
simp only [mem_bind_iff]
exact ⟨fun ⟨_, ⟨_, h₁, h₂⟩, h₃⟩ => ⟨_, h₁, _, h₂, h₃⟩,
fun ⟨_, h₁, _, h₂, h₃⟩ => ⟨_, ⟨_, h₁, h₂⟩, h₃⟩⟩
#align part.bind_assoc Part.bind_assoc
@[simp]
theorem bind_map {γ} (f : α → β) (x) (g : β → Part γ) :
(map f x).bind g = x.bind fun y => g (f y) := by rw [← bind_some_eq_map, bind_assoc]; simp
#align part.bind_map Part.bind_map
@[simp]
theorem map_bind {γ} (f : α → Part β) (x : Part α) (g : β → γ) :
map g (x.bind f) = x.bind fun y => map g (f y) := by
rw [← bind_some_eq_map, bind_assoc]; simp [bind_some_eq_map]
#align part.map_bind Part.map_bind
theorem map_map (g : β → γ) (f : α → β) (o : Part α) : map g (map f o) = map (g ∘ f) o := by
erw [← bind_some_eq_map, bind_map, bind_some_eq_map]
#align part.map_map Part.map_map
instance : Monad Part where
pure := @some
map := @map
bind := @Part.bind
instance : LawfulMonad
Part where
bind_pure_comp := @bind_some_eq_map
id_map f := by cases f; rfl
pure_bind := @bind_some
bind_assoc := @bind_assoc
map_const := by simp [Functor.mapConst, Functor.map]
--Porting TODO : In Lean3 these were automatic by a tactic
seqLeft_eq x y := ext'
(by simp [SeqLeft.seqLeft, Part.bind, assert, Seq.seq, const, (· <$> ·), and_comm])
(fun _ _ => rfl)
seqRight_eq x y := ext'
(by simp [SeqRight.seqRight, Part.bind, assert, Seq.seq, const, (· <$> ·), and_comm])
(fun _ _ => rfl)
pure_seq x y := ext'
(by simp [Seq.seq, Part.bind, assert, (· <$> ·), pure])
(fun _ _ => rfl)
bind_map x y := ext'
(by simp [(· >>= ·), Part.bind, assert, Seq.seq, get, (· <$> ·)] )
(fun _ _ => rfl)
| Mathlib/Data/Part.lean | 587 | 588 | theorem map_id' {f : α → α} (H : ∀ x : α, f x = x) (o) : map f o = o := by |
rw [show f = id from funext H]; exact id_map o
|
import Mathlib.MeasureTheory.Measure.GiryMonad
import Mathlib.Dynamics.Ergodic.MeasurePreserving
import Mathlib.MeasureTheory.Integral.Lebesgue
import Mathlib.MeasureTheory.Measure.OpenPos
#align_import measure_theory.constructions.prod.basic from "leanprover-community/mathlib"@"00abe0695d8767201e6d008afa22393978bb324d"
noncomputable section
open scoped Classical
open Topology ENNReal MeasureTheory
open Set Function Real ENNReal
open MeasureTheory MeasurableSpace MeasureTheory.Measure
open TopologicalSpace hiding generateFrom
open Filter hiding prod_eq map
variable {α α' β β' γ E : Type*}
theorem IsPiSystem.prod {C : Set (Set α)} {D : Set (Set β)} (hC : IsPiSystem C)
(hD : IsPiSystem D) : IsPiSystem (image2 (· ×ˢ ·) C D) := by
rintro _ ⟨s₁, hs₁, t₁, ht₁, rfl⟩ _ ⟨s₂, hs₂, t₂, ht₂, rfl⟩ hst
rw [prod_inter_prod] at hst ⊢; rw [prod_nonempty_iff] at hst
exact mem_image2_of_mem (hC _ hs₁ _ hs₂ hst.1) (hD _ ht₁ _ ht₂ hst.2)
#align is_pi_system.prod IsPiSystem.prod
theorem IsCountablySpanning.prod {C : Set (Set α)} {D : Set (Set β)} (hC : IsCountablySpanning C)
(hD : IsCountablySpanning D) : IsCountablySpanning (image2 (· ×ˢ ·) C D) := by
rcases hC, hD with ⟨⟨s, h1s, h2s⟩, t, h1t, h2t⟩
refine ⟨fun n => s n.unpair.1 ×ˢ t n.unpair.2, fun n => mem_image2_of_mem (h1s _) (h1t _), ?_⟩
rw [iUnion_unpair_prod, h2s, h2t, univ_prod_univ]
#align is_countably_spanning.prod IsCountablySpanning.prod
variable [MeasurableSpace α] [MeasurableSpace α'] [MeasurableSpace β] [MeasurableSpace β']
variable [MeasurableSpace γ]
variable {μ μ' : Measure α} {ν ν' : Measure β} {τ : Measure γ}
variable [NormedAddCommGroup E]
theorem generateFrom_prod_eq {α β} {C : Set (Set α)} {D : Set (Set β)} (hC : IsCountablySpanning C)
(hD : IsCountablySpanning D) :
@Prod.instMeasurableSpace _ _ (generateFrom C) (generateFrom D) =
generateFrom (image2 (· ×ˢ ·) C D) := by
apply le_antisymm
· refine sup_le ?_ ?_ <;> rw [comap_generateFrom] <;> apply generateFrom_le <;>
rintro _ ⟨s, hs, rfl⟩
· rcases hD with ⟨t, h1t, h2t⟩
rw [← prod_univ, ← h2t, prod_iUnion]
apply MeasurableSet.iUnion
intro n
apply measurableSet_generateFrom
exact ⟨s, hs, t n, h1t n, rfl⟩
· rcases hC with ⟨t, h1t, h2t⟩
rw [← univ_prod, ← h2t, iUnion_prod_const]
apply MeasurableSet.iUnion
rintro n
apply measurableSet_generateFrom
exact mem_image2_of_mem (h1t n) hs
· apply generateFrom_le
rintro _ ⟨s, hs, t, ht, rfl⟩
dsimp only
rw [prod_eq]
apply (measurable_fst _).inter (measurable_snd _)
· exact measurableSet_generateFrom hs
· exact measurableSet_generateFrom ht
#align generate_from_prod_eq generateFrom_prod_eq
theorem generateFrom_eq_prod {C : Set (Set α)} {D : Set (Set β)} (hC : generateFrom C = ‹_›)
(hD : generateFrom D = ‹_›) (h2C : IsCountablySpanning C) (h2D : IsCountablySpanning D) :
generateFrom (image2 (· ×ˢ ·) C D) = Prod.instMeasurableSpace := by
rw [← hC, ← hD, generateFrom_prod_eq h2C h2D]
#align generate_from_eq_prod generateFrom_eq_prod
theorem generateFrom_prod :
generateFrom (image2 (· ×ˢ ·) { s : Set α | MeasurableSet s } { t : Set β | MeasurableSet t }) =
Prod.instMeasurableSpace :=
generateFrom_eq_prod generateFrom_measurableSet generateFrom_measurableSet
isCountablySpanning_measurableSet isCountablySpanning_measurableSet
#align generate_from_prod generateFrom_prod
theorem isPiSystem_prod :
IsPiSystem (image2 (· ×ˢ ·) { s : Set α | MeasurableSet s } { t : Set β | MeasurableSet t }) :=
isPiSystem_measurableSet.prod isPiSystem_measurableSet
#align is_pi_system_prod isPiSystem_prod
theorem measurable_measure_prod_mk_left_finite [IsFiniteMeasure ν] {s : Set (α × β)}
(hs : MeasurableSet s) : Measurable fun x => ν (Prod.mk x ⁻¹' s) := by
refine induction_on_inter (C := fun s => Measurable fun x => ν (Prod.mk x ⁻¹' s))
generateFrom_prod.symm isPiSystem_prod ?_ ?_ ?_ ?_ hs
· simp
· rintro _ ⟨s, hs, t, _, rfl⟩
simp only [mk_preimage_prod_right_eq_if, measure_if]
exact measurable_const.indicator hs
· intro t ht h2t
simp_rw [preimage_compl, measure_compl (measurable_prod_mk_left ht) (measure_ne_top ν _)]
exact h2t.const_sub _
· intro f h1f h2f h3f
simp_rw [preimage_iUnion]
have : ∀ b, ν (⋃ i, Prod.mk b ⁻¹' f i) = ∑' i, ν (Prod.mk b ⁻¹' f i) := fun b =>
measure_iUnion (fun i j hij => Disjoint.preimage _ (h1f hij)) fun i =>
measurable_prod_mk_left (h2f i)
simp_rw [this]
apply Measurable.ennreal_tsum h3f
#align measurable_measure_prod_mk_left_finite measurable_measure_prod_mk_left_finite
theorem measurable_measure_prod_mk_left [SFinite ν] {s : Set (α × β)} (hs : MeasurableSet s) :
Measurable fun x => ν (Prod.mk x ⁻¹' s) := by
rw [← sum_sFiniteSeq ν]
simp_rw [Measure.sum_apply_of_countable]
exact Measurable.ennreal_tsum (fun i ↦ measurable_measure_prod_mk_left_finite hs)
#align measurable_measure_prod_mk_left measurable_measure_prod_mk_left
theorem measurable_measure_prod_mk_right {μ : Measure α} [SFinite μ] {s : Set (α × β)}
(hs : MeasurableSet s) : Measurable fun y => μ ((fun x => (x, y)) ⁻¹' s) :=
measurable_measure_prod_mk_left (measurableSet_swap_iff.mpr hs)
#align measurable_measure_prod_mk_right measurable_measure_prod_mk_right
theorem Measurable.map_prod_mk_left [SFinite ν] :
Measurable fun x : α => map (Prod.mk x) ν := by
apply measurable_of_measurable_coe; intro s hs
simp_rw [map_apply measurable_prod_mk_left hs]
exact measurable_measure_prod_mk_left hs
#align measurable.map_prod_mk_left Measurable.map_prod_mk_left
theorem Measurable.map_prod_mk_right {μ : Measure α} [SFinite μ] :
Measurable fun y : β => map (fun x : α => (x, y)) μ := by
apply measurable_of_measurable_coe; intro s hs
simp_rw [map_apply measurable_prod_mk_right hs]
exact measurable_measure_prod_mk_right hs
#align measurable.map_prod_mk_right Measurable.map_prod_mk_right
theorem MeasurableEmbedding.prod_mk {α β γ δ : Type*} {mα : MeasurableSpace α}
{mβ : MeasurableSpace β} {mγ : MeasurableSpace γ} {mδ : MeasurableSpace δ} {f : α → β}
{g : γ → δ} (hg : MeasurableEmbedding g) (hf : MeasurableEmbedding f) :
MeasurableEmbedding fun x : γ × α => (g x.1, f x.2) := by
have h_inj : Function.Injective fun x : γ × α => (g x.fst, f x.snd) := by
intro x y hxy
rw [← @Prod.mk.eta _ _ x, ← @Prod.mk.eta _ _ y]
simp only [Prod.mk.inj_iff] at hxy ⊢
exact ⟨hg.injective hxy.1, hf.injective hxy.2⟩
refine ⟨h_inj, ?_, ?_⟩
· exact (hg.measurable.comp measurable_fst).prod_mk (hf.measurable.comp measurable_snd)
· -- Induction using the π-system of rectangles
refine fun s hs =>
@MeasurableSpace.induction_on_inter _
(fun s => MeasurableSet ((fun x : γ × α => (g x.fst, f x.snd)) '' s)) _ _
generateFrom_prod.symm isPiSystem_prod ?_ ?_ ?_ ?_ _ hs
· simp only [Set.image_empty, MeasurableSet.empty]
· rintro t ⟨t₁, ht₁, t₂, ht₂, rfl⟩
rw [← Set.prod_image_image_eq]
exact (hg.measurableSet_image.mpr ht₁).prod (hf.measurableSet_image.mpr ht₂)
· intro t _ ht_m
rw [← Set.range_diff_image h_inj, ← Set.prod_range_range_eq]
exact
MeasurableSet.diff (MeasurableSet.prod hg.measurableSet_range hf.measurableSet_range) ht_m
· intro g _ _ hg
simp_rw [Set.image_iUnion]
exact MeasurableSet.iUnion hg
#align measurable_embedding.prod_mk MeasurableEmbedding.prod_mk
lemma MeasurableEmbedding.prod_mk_left {β γ : Type*} [MeasurableSingletonClass α]
{mβ : MeasurableSpace β} {mγ : MeasurableSpace γ}
(x : α) {f : γ → β} (hf : MeasurableEmbedding f) :
MeasurableEmbedding (fun y ↦ (x, f y)) where
injective := by
intro y y'
simp only [Prod.mk.injEq, true_and]
exact fun h ↦ hf.injective h
measurable := Measurable.prod_mk measurable_const hf.measurable
measurableSet_image' := by
intro s hs
convert (MeasurableSet.singleton x).prod (hf.measurableSet_image.mpr hs)
ext x
simp
lemma measurableEmbedding_prod_mk_left [MeasurableSingletonClass α] (x : α) :
MeasurableEmbedding (Prod.mk x : β → α × β) :=
MeasurableEmbedding.prod_mk_left x MeasurableEmbedding.id
lemma MeasurableEmbedding.prod_mk_right {β γ : Type*} [MeasurableSingletonClass α]
{mβ : MeasurableSpace β} {mγ : MeasurableSpace γ}
{f : γ → β} (hf : MeasurableEmbedding f) (x : α) :
MeasurableEmbedding (fun y ↦ (f y, x)) where
injective := by
intro y y'
simp only [Prod.mk.injEq, and_true]
exact fun h ↦ hf.injective h
measurable := Measurable.prod_mk hf.measurable measurable_const
measurableSet_image' := by
intro s hs
convert (hf.measurableSet_image.mpr hs).prod (MeasurableSet.singleton x)
ext x
simp
lemma measurableEmbedding_prod_mk_right [MeasurableSingletonClass α] (x : α) :
MeasurableEmbedding (fun y ↦ (y, x) : β → β × α) :=
MeasurableEmbedding.prod_mk_right MeasurableEmbedding.id x
theorem Measurable.lintegral_prod_right' [SFinite ν] :
∀ {f : α × β → ℝ≥0∞}, Measurable f → Measurable fun x => ∫⁻ y, f (x, y) ∂ν := by
have m := @measurable_prod_mk_left
refine Measurable.ennreal_induction (P := fun f => Measurable fun (x : α) => ∫⁻ y, f (x, y) ∂ν)
?_ ?_ ?_
· intro c s hs
simp only [← indicator_comp_right]
suffices Measurable fun x => c * ν (Prod.mk x ⁻¹' s) by simpa [lintegral_indicator _ (m hs)]
exact (measurable_measure_prod_mk_left hs).const_mul _
· rintro f g - hf - h2f h2g
simp only [Pi.add_apply]
conv => enter [1, x]; erw [lintegral_add_left (hf.comp m)]
exact h2f.add h2g
· intro f hf h2f h3f
have := measurable_iSup h3f
have : ∀ x, Monotone fun n y => f n (x, y) := fun x i j hij y => h2f hij (x, y)
conv => enter [1, x]; erw [lintegral_iSup (fun n => (hf n).comp m) (this x)]
assumption
#align measurable.lintegral_prod_right' Measurable.lintegral_prod_right'
theorem Measurable.lintegral_prod_right [SFinite ν] {f : α → β → ℝ≥0∞}
(hf : Measurable (uncurry f)) : Measurable fun x => ∫⁻ y, f x y ∂ν :=
hf.lintegral_prod_right'
#align measurable.lintegral_prod_right Measurable.lintegral_prod_right
theorem Measurable.lintegral_prod_left' [SFinite μ] {f : α × β → ℝ≥0∞} (hf : Measurable f) :
Measurable fun y => ∫⁻ x, f (x, y) ∂μ :=
(measurable_swap_iff.mpr hf).lintegral_prod_right'
#align measurable.lintegral_prod_left' Measurable.lintegral_prod_left'
theorem Measurable.lintegral_prod_left [SFinite μ] {f : α → β → ℝ≥0∞}
(hf : Measurable (uncurry f)) : Measurable fun y => ∫⁻ x, f x y ∂μ :=
hf.lintegral_prod_left'
#align measurable.lintegral_prod_left Measurable.lintegral_prod_left
namespace MeasureTheory
namespace Measure
protected irreducible_def prod (μ : Measure α) (ν : Measure β) : Measure (α × β) :=
bind μ fun x : α => map (Prod.mk x) ν
#align measure_theory.measure.prod MeasureTheory.Measure.prod
instance prod.measureSpace {α β} [MeasureSpace α] [MeasureSpace β] : MeasureSpace (α × β) where
volume := volume.prod volume
#align measure_theory.measure.prod.measure_space MeasureTheory.Measure.prod.measureSpace
theorem volume_eq_prod (α β) [MeasureSpace α] [MeasureSpace β] :
(volume : Measure (α × β)) = (volume : Measure α).prod (volume : Measure β) :=
rfl
#align measure_theory.measure.volume_eq_prod MeasureTheory.Measure.volume_eq_prod
variable [SFinite ν]
theorem prod_apply {s : Set (α × β)} (hs : MeasurableSet s) :
μ.prod ν s = ∫⁻ x, ν (Prod.mk x ⁻¹' s) ∂μ := by
simp_rw [Measure.prod, bind_apply hs (Measurable.map_prod_mk_left (ν := ν)),
map_apply measurable_prod_mk_left hs]
#align measure_theory.measure.prod_apply MeasureTheory.Measure.prod_apply
@[simp]
theorem prod_prod (s : Set α) (t : Set β) : μ.prod ν (s ×ˢ t) = μ s * ν t := by
apply le_antisymm
· set S := toMeasurable μ s
set T := toMeasurable ν t
have hSTm : MeasurableSet (S ×ˢ T) :=
(measurableSet_toMeasurable _ _).prod (measurableSet_toMeasurable _ _)
calc
μ.prod ν (s ×ˢ t) ≤ μ.prod ν (S ×ˢ T) := by gcongr <;> apply subset_toMeasurable
_ = μ S * ν T := by
rw [prod_apply hSTm]
simp_rw [mk_preimage_prod_right_eq_if, measure_if,
lintegral_indicator _ (measurableSet_toMeasurable _ _), lintegral_const,
restrict_apply_univ, mul_comm]
_ = μ s * ν t := by rw [measure_toMeasurable, measure_toMeasurable]
· -- Formalization is based on https://mathoverflow.net/a/254134/136589
set ST := toMeasurable (μ.prod ν) (s ×ˢ t)
have hSTm : MeasurableSet ST := measurableSet_toMeasurable _ _
have hST : s ×ˢ t ⊆ ST := subset_toMeasurable _ _
set f : α → ℝ≥0∞ := fun x => ν (Prod.mk x ⁻¹' ST)
have hfm : Measurable f := measurable_measure_prod_mk_left hSTm
set s' : Set α := { x | ν t ≤ f x }
have hss' : s ⊆ s' := fun x hx => measure_mono fun y hy => hST <| mk_mem_prod hx hy
calc
μ s * ν t ≤ μ s' * ν t := by gcongr
_ = ∫⁻ _ in s', ν t ∂μ := by rw [set_lintegral_const, mul_comm]
_ ≤ ∫⁻ x in s', f x ∂μ := set_lintegral_mono measurable_const hfm fun x => id
_ ≤ ∫⁻ x, f x ∂μ := lintegral_mono' restrict_le_self le_rfl
_ = μ.prod ν ST := (prod_apply hSTm).symm
_ = μ.prod ν (s ×ˢ t) := measure_toMeasurable _
#align measure_theory.measure.prod_prod MeasureTheory.Measure.prod_prod
@[simp] lemma map_fst_prod : Measure.map Prod.fst (μ.prod ν) = (ν univ) • μ := by
ext s hs
simp [Measure.map_apply measurable_fst hs, ← prod_univ, mul_comm]
@[simp] lemma map_snd_prod : Measure.map Prod.snd (μ.prod ν) = (μ univ) • ν := by
ext s hs
simp [Measure.map_apply measurable_snd hs, ← univ_prod]
instance prod.instIsOpenPosMeasure {X Y : Type*} [TopologicalSpace X] [TopologicalSpace Y]
{m : MeasurableSpace X} {μ : Measure X} [IsOpenPosMeasure μ] {m' : MeasurableSpace Y}
{ν : Measure Y} [IsOpenPosMeasure ν] [SFinite ν] : IsOpenPosMeasure (μ.prod ν) := by
constructor
rintro U U_open ⟨⟨x, y⟩, hxy⟩
rcases isOpen_prod_iff.1 U_open x y hxy with ⟨u, v, u_open, v_open, xu, yv, huv⟩
refine ne_of_gt (lt_of_lt_of_le ?_ (measure_mono huv))
simp only [prod_prod, CanonicallyOrderedCommSemiring.mul_pos]
constructor
· exact u_open.measure_pos μ ⟨x, xu⟩
· exact v_open.measure_pos ν ⟨y, yv⟩
#align measure_theory.measure.prod.is_open_pos_measure MeasureTheory.Measure.prod.instIsOpenPosMeasure
instance {X Y : Type*}
[TopologicalSpace X] [MeasureSpace X] [IsOpenPosMeasure (volume : Measure X)]
[TopologicalSpace Y] [MeasureSpace Y] [IsOpenPosMeasure (volume : Measure Y)]
[SFinite (volume : Measure Y)] : IsOpenPosMeasure (volume : Measure (X × Y)) :=
prod.instIsOpenPosMeasure
instance prod.instIsFiniteMeasure {α β : Type*} {mα : MeasurableSpace α} {mβ : MeasurableSpace β}
(μ : Measure α) (ν : Measure β) [IsFiniteMeasure μ] [IsFiniteMeasure ν] :
IsFiniteMeasure (μ.prod ν) := by
constructor
rw [← univ_prod_univ, prod_prod]
exact mul_lt_top (measure_lt_top _ _).ne (measure_lt_top _ _).ne
#align measure_theory.measure.prod.measure_theory.is_finite_measure MeasureTheory.Measure.prod.instIsFiniteMeasure
instance {α β : Type*} [MeasureSpace α] [MeasureSpace β] [IsFiniteMeasure (volume : Measure α)]
[IsFiniteMeasure (volume : Measure β)] : IsFiniteMeasure (volume : Measure (α × β)) :=
prod.instIsFiniteMeasure _ _
instance prod.instIsProbabilityMeasure {α β : Type*} {mα : MeasurableSpace α}
{mβ : MeasurableSpace β} (μ : Measure α) (ν : Measure β) [IsProbabilityMeasure μ]
[IsProbabilityMeasure ν] : IsProbabilityMeasure (μ.prod ν) :=
⟨by rw [← univ_prod_univ, prod_prod, measure_univ, measure_univ, mul_one]⟩
#align measure_theory.measure.prod.measure_theory.is_probability_measure MeasureTheory.Measure.prod.instIsProbabilityMeasure
instance {α β : Type*} [MeasureSpace α] [MeasureSpace β]
[IsProbabilityMeasure (volume : Measure α)] [IsProbabilityMeasure (volume : Measure β)] :
IsProbabilityMeasure (volume : Measure (α × β)) :=
prod.instIsProbabilityMeasure _ _
instance prod.instIsFiniteMeasureOnCompacts {α β : Type*} [TopologicalSpace α] [TopologicalSpace β]
{mα : MeasurableSpace α} {mβ : MeasurableSpace β} (μ : Measure α) (ν : Measure β)
[IsFiniteMeasureOnCompacts μ] [IsFiniteMeasureOnCompacts ν] [SFinite ν] :
IsFiniteMeasureOnCompacts (μ.prod ν) := by
refine ⟨fun K hK => ?_⟩
set L := (Prod.fst '' K) ×ˢ (Prod.snd '' K) with hL
have : K ⊆ L := by
rintro ⟨x, y⟩ hxy
simp only [L, prod_mk_mem_set_prod_eq, mem_image, Prod.exists, exists_and_right,
exists_eq_right]
exact ⟨⟨y, hxy⟩, ⟨x, hxy⟩⟩
apply lt_of_le_of_lt (measure_mono this)
rw [hL, prod_prod]
exact
mul_lt_top (IsCompact.measure_lt_top (hK.image continuous_fst)).ne
(IsCompact.measure_lt_top (hK.image continuous_snd)).ne
#align measure_theory.measure.prod.measure_theory.is_finite_measure_on_compacts MeasureTheory.Measure.prod.instIsFiniteMeasureOnCompacts
instance {X Y : Type*}
[TopologicalSpace X] [MeasureSpace X] [IsFiniteMeasureOnCompacts (volume : Measure X)]
[TopologicalSpace Y] [MeasureSpace Y] [IsFiniteMeasureOnCompacts (volume : Measure Y)]
[SFinite (volume : Measure Y)] : IsFiniteMeasureOnCompacts (volume : Measure (X × Y)) :=
prod.instIsFiniteMeasureOnCompacts _ _
instance prod.instNoAtoms_fst [NoAtoms μ] :
NoAtoms (Measure.prod μ ν) := by
refine NoAtoms.mk (fun x => ?_)
rw [← Set.singleton_prod_singleton, Measure.prod_prod, measure_singleton, zero_mul]
instance prod.instNoAtoms_snd [NoAtoms ν] :
NoAtoms (Measure.prod μ ν) := by
refine NoAtoms.mk (fun x => ?_)
rw [← Set.singleton_prod_singleton, Measure.prod_prod, measure_singleton (μ := ν), mul_zero]
theorem ae_measure_lt_top {s : Set (α × β)} (hs : MeasurableSet s) (h2s : (μ.prod ν) s ≠ ∞) :
∀ᵐ x ∂μ, ν (Prod.mk x ⁻¹' s) < ∞ := by
rw [prod_apply hs] at h2s
exact ae_lt_top (measurable_measure_prod_mk_left hs) h2s
#align measure_theory.measure.ae_measure_lt_top MeasureTheory.Measure.ae_measure_lt_top
theorem measure_prod_null {s : Set (α × β)} (hs : MeasurableSet s) :
μ.prod ν s = 0 ↔ (fun x => ν (Prod.mk x ⁻¹' s)) =ᵐ[μ] 0 := by
rw [prod_apply hs, lintegral_eq_zero_iff (measurable_measure_prod_mk_left hs)]
#align measure_theory.measure.measure_prod_null MeasureTheory.Measure.measure_prod_null
theorem measure_ae_null_of_prod_null {s : Set (α × β)} (h : μ.prod ν s = 0) :
(fun x => ν (Prod.mk x ⁻¹' s)) =ᵐ[μ] 0 := by
obtain ⟨t, hst, mt, ht⟩ := exists_measurable_superset_of_null h
rw [measure_prod_null mt] at ht
rw [eventuallyLE_antisymm_iff]
exact
⟨EventuallyLE.trans_eq (eventually_of_forall fun x => (measure_mono (preimage_mono hst) : _))
ht,
eventually_of_forall fun x => zero_le _⟩
#align measure_theory.measure.measure_ae_null_of_prod_null MeasureTheory.Measure.measure_ae_null_of_prod_null
theorem AbsolutelyContinuous.prod [SFinite ν'] (h1 : μ ≪ μ') (h2 : ν ≪ ν') :
μ.prod ν ≪ μ'.prod ν' := by
refine AbsolutelyContinuous.mk fun s hs h2s => ?_
rw [measure_prod_null hs] at h2s ⊢
exact (h2s.filter_mono h1.ae_le).mono fun _ h => h2 h
#align measure_theory.measure.absolutely_continuous.prod MeasureTheory.Measure.AbsolutelyContinuous.prod
theorem ae_ae_of_ae_prod {p : α × β → Prop} (h : ∀ᵐ z ∂μ.prod ν, p z) :
∀ᵐ x ∂μ, ∀ᵐ y ∂ν, p (x, y) :=
measure_ae_null_of_prod_null h
#align measure_theory.measure.ae_ae_of_ae_prod MeasureTheory.Measure.ae_ae_of_ae_prod
theorem ae_ae_eq_curry_of_prod {f g : α × β → γ} (h : f =ᵐ[μ.prod ν] g) :
∀ᵐ x ∂μ, curry f x =ᵐ[ν] curry g x :=
ae_ae_of_ae_prod h
theorem ae_ae_eq_of_ae_eq_uncurry {f g : α → β → γ} (h : uncurry f =ᵐ[μ.prod ν] uncurry g) :
∀ᵐ x ∂μ, f x =ᵐ[ν] g x :=
ae_ae_eq_curry_of_prod h
theorem ae_prod_mem_iff_ae_ae_mem {s : Set (α × β)} (hs : MeasurableSet s) :
(∀ᵐ z ∂μ.prod ν, z ∈ s) ↔ ∀ᵐ x ∂μ, ∀ᵐ y ∂ν, (x, y) ∈ s :=
measure_prod_null hs.compl
theorem quasiMeasurePreserving_fst : QuasiMeasurePreserving Prod.fst (μ.prod ν) μ := by
refine ⟨measurable_fst, AbsolutelyContinuous.mk fun s hs h2s => ?_⟩
rw [map_apply measurable_fst hs, ← prod_univ, prod_prod, h2s, zero_mul]
#align measure_theory.measure.quasi_measure_preserving_fst MeasureTheory.Measure.quasiMeasurePreserving_fst
| Mathlib/MeasureTheory/Constructions/Prod/Basic.lean | 523 | 525 | theorem quasiMeasurePreserving_snd : QuasiMeasurePreserving Prod.snd (μ.prod ν) ν := by |
refine ⟨measurable_snd, AbsolutelyContinuous.mk fun s hs h2s => ?_⟩
rw [map_apply measurable_snd hs, ← univ_prod, prod_prod, h2s, mul_zero]
|
import Mathlib.Order.UpperLower.Basic
import Mathlib.Data.Finset.Preimage
#align_import combinatorics.young.young_diagram from "leanprover-community/mathlib"@"59694bd07f0a39c5beccba34bd9f413a160782bf"
open Function
@[ext]
structure YoungDiagram where
cells : Finset (ℕ × ℕ)
isLowerSet : IsLowerSet (cells : Set (ℕ × ℕ))
#align young_diagram YoungDiagram
namespace YoungDiagram
instance : SetLike YoungDiagram (ℕ × ℕ) where
-- Porting note (#11215): TODO: figure out how to do this correctly
coe := fun y => y.cells
coe_injective' μ ν h := by rwa [YoungDiagram.ext_iff, ← Finset.coe_inj]
@[simp]
theorem mem_cells {μ : YoungDiagram} (c : ℕ × ℕ) : c ∈ μ.cells ↔ c ∈ μ :=
Iff.rfl
#align young_diagram.mem_cells YoungDiagram.mem_cells
@[simp]
theorem mem_mk (c : ℕ × ℕ) (cells) (isLowerSet) :
c ∈ YoungDiagram.mk cells isLowerSet ↔ c ∈ cells :=
Iff.rfl
#align young_diagram.mem_mk YoungDiagram.mem_mk
instance decidableMem (μ : YoungDiagram) : DecidablePred (· ∈ μ) :=
inferInstanceAs (DecidablePred (· ∈ μ.cells))
#align young_diagram.decidable_mem YoungDiagram.decidableMem
theorem up_left_mem (μ : YoungDiagram) {i1 i2 j1 j2 : ℕ} (hi : i1 ≤ i2) (hj : j1 ≤ j2)
(hcell : (i2, j2) ∈ μ) : (i1, j1) ∈ μ :=
μ.isLowerSet (Prod.mk_le_mk.mpr ⟨hi, hj⟩) hcell
#align young_diagram.up_left_mem YoungDiagram.up_left_mem
section DistribLattice
@[simp]
theorem cells_subset_iff {μ ν : YoungDiagram} : μ.cells ⊆ ν.cells ↔ μ ≤ ν :=
Iff.rfl
#align young_diagram.cells_subset_iff YoungDiagram.cells_subset_iff
@[simp]
theorem cells_ssubset_iff {μ ν : YoungDiagram} : μ.cells ⊂ ν.cells ↔ μ < ν :=
Iff.rfl
#align young_diagram.cells_ssubset_iff YoungDiagram.cells_ssubset_iff
instance : Sup YoungDiagram where
sup μ ν :=
{ cells := μ.cells ∪ ν.cells
isLowerSet := by
rw [Finset.coe_union]
exact μ.isLowerSet.union ν.isLowerSet }
@[simp]
theorem cells_sup (μ ν : YoungDiagram) : (μ ⊔ ν).cells = μ.cells ∪ ν.cells :=
rfl
#align young_diagram.cells_sup YoungDiagram.cells_sup
@[simp, norm_cast]
theorem coe_sup (μ ν : YoungDiagram) : ↑(μ ⊔ ν) = (μ ∪ ν : Set (ℕ × ℕ)) :=
Finset.coe_union _ _
#align young_diagram.coe_sup YoungDiagram.coe_sup
@[simp]
theorem mem_sup {μ ν : YoungDiagram} {x : ℕ × ℕ} : x ∈ μ ⊔ ν ↔ x ∈ μ ∨ x ∈ ν :=
Finset.mem_union
#align young_diagram.mem_sup YoungDiagram.mem_sup
instance : Inf YoungDiagram where
inf μ ν :=
{ cells := μ.cells ∩ ν.cells
isLowerSet := by
rw [Finset.coe_inter]
exact μ.isLowerSet.inter ν.isLowerSet }
@[simp]
theorem cells_inf (μ ν : YoungDiagram) : (μ ⊓ ν).cells = μ.cells ∩ ν.cells :=
rfl
#align young_diagram.cells_inf YoungDiagram.cells_inf
@[simp, norm_cast]
theorem coe_inf (μ ν : YoungDiagram) : ↑(μ ⊓ ν) = (μ ∩ ν : Set (ℕ × ℕ)) :=
Finset.coe_inter _ _
#align young_diagram.coe_inf YoungDiagram.coe_inf
@[simp]
theorem mem_inf {μ ν : YoungDiagram} {x : ℕ × ℕ} : x ∈ μ ⊓ ν ↔ x ∈ μ ∧ x ∈ ν :=
Finset.mem_inter
#align young_diagram.mem_inf YoungDiagram.mem_inf
instance : OrderBot YoungDiagram where
bot :=
{ cells := ∅
isLowerSet := by
intros a b _ h
simp only [Finset.coe_empty, Set.mem_empty_iff_false]
simp only [Finset.coe_empty, Set.mem_empty_iff_false] at h }
bot_le _ _ := by
intro y
simp only [mem_mk, Finset.not_mem_empty] at y
@[simp]
theorem cells_bot : (⊥ : YoungDiagram).cells = ∅ :=
rfl
#align young_diagram.cells_bot YoungDiagram.cells_bot
-- Porting note: removed `↑`, added `.cells` and changed proof
-- @[simp] -- Porting note (#10618): simp can prove this
@[norm_cast]
| Mathlib/Combinatorics/Young/YoungDiagram.lean | 174 | 179 | theorem coe_bot : (⊥ : YoungDiagram).cells = (∅ : Set (ℕ × ℕ)) := by |
refine Set.eq_of_subset_of_subset ?_ ?_
· intros x h
simp? [mem_mk, Finset.coe_empty, Set.mem_empty_iff_false] at h says
simp only [cells_bot, Finset.coe_empty, Set.mem_empty_iff_false] at h
· simp only [cells_bot, Finset.coe_empty, Set.empty_subset]
|
import Mathlib.SetTheory.Ordinal.Basic
import Mathlib.Data.Nat.SuccPred
#align_import set_theory.ordinal.arithmetic from "leanprover-community/mathlib"@"31b269b60935483943542d547a6dd83a66b37dc7"
assert_not_exists Field
assert_not_exists Module
noncomputable section
open Function Cardinal Set Equiv Order
open scoped Classical
open Cardinal Ordinal
universe u v w
namespace Ordinal
variable {α : Type*} {β : Type*} {γ : Type*} {r : α → α → Prop} {s : β → β → Prop}
{t : γ → γ → Prop}
@[simp]
theorem lift_add (a b : Ordinal.{v}) : lift.{u} (a + b) = lift.{u} a + lift.{u} b :=
Quotient.inductionOn₂ a b fun ⟨_α, _r, _⟩ ⟨_β, _s, _⟩ =>
Quotient.sound
⟨(RelIso.preimage Equiv.ulift _).trans
(RelIso.sumLexCongr (RelIso.preimage Equiv.ulift _) (RelIso.preimage Equiv.ulift _)).symm⟩
#align ordinal.lift_add Ordinal.lift_add
@[simp]
theorem lift_succ (a : Ordinal.{v}) : lift.{u} (succ a) = succ (lift.{u} a) := by
rw [← add_one_eq_succ, lift_add, lift_one]
rfl
#align ordinal.lift_succ Ordinal.lift_succ
instance add_contravariantClass_le : ContravariantClass Ordinal.{u} Ordinal.{u} (· + ·) (· ≤ ·) :=
⟨fun a b c =>
inductionOn a fun α r hr =>
inductionOn b fun β₁ s₁ hs₁ =>
inductionOn c fun β₂ s₂ hs₂ ⟨f⟩ =>
⟨have fl : ∀ a, f (Sum.inl a) = Sum.inl a := fun a => by
simpa only [InitialSeg.trans_apply, InitialSeg.leAdd_apply] using
@InitialSeg.eq _ _ _ _ _
((InitialSeg.leAdd r s₁).trans f) (InitialSeg.leAdd r s₂) a
have : ∀ b, { b' // f (Sum.inr b) = Sum.inr b' } := by
intro b; cases e : f (Sum.inr b)
· rw [← fl] at e
have := f.inj' e
contradiction
· exact ⟨_, rfl⟩
let g (b) := (this b).1
have fr : ∀ b, f (Sum.inr b) = Sum.inr (g b) := fun b => (this b).2
⟨⟨⟨g, fun x y h => by
injection f.inj' (by rw [fr, fr, h] : f (Sum.inr x) = f (Sum.inr y))⟩,
@fun a b => by
-- Porting note:
-- `relEmbedding.coe_fn_to_embedding` & `initial_seg.coe_fn_to_rel_embedding`
-- → `InitialSeg.coe_coe_fn`
simpa only [Sum.lex_inr_inr, fr, InitialSeg.coe_coe_fn, Embedding.coeFn_mk] using
@RelEmbedding.map_rel_iff _ _ _ _ f.toRelEmbedding (Sum.inr a) (Sum.inr b)⟩,
fun a b H => by
rcases f.init (by rw [fr] <;> exact Sum.lex_inr_inr.2 H) with ⟨a' | a', h⟩
· rw [fl] at h
cases h
· rw [fr] at h
exact ⟨a', Sum.inr.inj h⟩⟩⟩⟩
#align ordinal.add_contravariant_class_le Ordinal.add_contravariantClass_le
theorem add_left_cancel (a) {b c : Ordinal} : a + b = a + c ↔ b = c := by
simp only [le_antisymm_iff, add_le_add_iff_left]
#align ordinal.add_left_cancel Ordinal.add_left_cancel
private theorem add_lt_add_iff_left' (a) {b c : Ordinal} : a + b < a + c ↔ b < c := by
rw [← not_le, ← not_le, add_le_add_iff_left]
instance add_covariantClass_lt : CovariantClass Ordinal.{u} Ordinal.{u} (· + ·) (· < ·) :=
⟨fun a _b _c => (add_lt_add_iff_left' a).2⟩
#align ordinal.add_covariant_class_lt Ordinal.add_covariantClass_lt
instance add_contravariantClass_lt : ContravariantClass Ordinal.{u} Ordinal.{u} (· + ·) (· < ·) :=
⟨fun a _b _c => (add_lt_add_iff_left' a).1⟩
#align ordinal.add_contravariant_class_lt Ordinal.add_contravariantClass_lt
instance add_swap_contravariantClass_lt :
ContravariantClass Ordinal.{u} Ordinal.{u} (swap (· + ·)) (· < ·) :=
⟨fun _a _b _c => lt_imp_lt_of_le_imp_le fun h => add_le_add_right h _⟩
#align ordinal.add_swap_contravariant_class_lt Ordinal.add_swap_contravariantClass_lt
theorem add_le_add_iff_right {a b : Ordinal} : ∀ n : ℕ, a + n ≤ b + n ↔ a ≤ b
| 0 => by simp
| n + 1 => by
simp only [natCast_succ, add_succ, add_succ, succ_le_succ_iff, add_le_add_iff_right]
#align ordinal.add_le_add_iff_right Ordinal.add_le_add_iff_right
theorem add_right_cancel {a b : Ordinal} (n : ℕ) : a + n = b + n ↔ a = b := by
simp only [le_antisymm_iff, add_le_add_iff_right]
#align ordinal.add_right_cancel Ordinal.add_right_cancel
theorem add_eq_zero_iff {a b : Ordinal} : a + b = 0 ↔ a = 0 ∧ b = 0 :=
inductionOn a fun α r _ =>
inductionOn b fun β s _ => by
simp_rw [← type_sum_lex, type_eq_zero_iff_isEmpty]
exact isEmpty_sum
#align ordinal.add_eq_zero_iff Ordinal.add_eq_zero_iff
theorem left_eq_zero_of_add_eq_zero {a b : Ordinal} (h : a + b = 0) : a = 0 :=
(add_eq_zero_iff.1 h).1
#align ordinal.left_eq_zero_of_add_eq_zero Ordinal.left_eq_zero_of_add_eq_zero
theorem right_eq_zero_of_add_eq_zero {a b : Ordinal} (h : a + b = 0) : b = 0 :=
(add_eq_zero_iff.1 h).2
#align ordinal.right_eq_zero_of_add_eq_zero Ordinal.right_eq_zero_of_add_eq_zero
def pred (o : Ordinal) : Ordinal :=
if h : ∃ a, o = succ a then Classical.choose h else o
#align ordinal.pred Ordinal.pred
@[simp]
theorem pred_succ (o) : pred (succ o) = o := by
have h : ∃ a, succ o = succ a := ⟨_, rfl⟩;
simpa only [pred, dif_pos h] using (succ_injective <| Classical.choose_spec h).symm
#align ordinal.pred_succ Ordinal.pred_succ
theorem pred_le_self (o) : pred o ≤ o :=
if h : ∃ a, o = succ a then by
let ⟨a, e⟩ := h
rw [e, pred_succ]; exact le_succ a
else by rw [pred, dif_neg h]
#align ordinal.pred_le_self Ordinal.pred_le_self
theorem pred_eq_iff_not_succ {o} : pred o = o ↔ ¬∃ a, o = succ a :=
⟨fun e ⟨a, e'⟩ => by rw [e', pred_succ] at e; exact (lt_succ a).ne e, fun h => dif_neg h⟩
#align ordinal.pred_eq_iff_not_succ Ordinal.pred_eq_iff_not_succ
theorem pred_eq_iff_not_succ' {o} : pred o = o ↔ ∀ a, o ≠ succ a := by
simpa using pred_eq_iff_not_succ
#align ordinal.pred_eq_iff_not_succ' Ordinal.pred_eq_iff_not_succ'
theorem pred_lt_iff_is_succ {o} : pred o < o ↔ ∃ a, o = succ a :=
Iff.trans (by simp only [le_antisymm_iff, pred_le_self, true_and_iff, not_le])
(iff_not_comm.1 pred_eq_iff_not_succ).symm
#align ordinal.pred_lt_iff_is_succ Ordinal.pred_lt_iff_is_succ
@[simp]
theorem pred_zero : pred 0 = 0 :=
pred_eq_iff_not_succ'.2 fun a => (succ_ne_zero a).symm
#align ordinal.pred_zero Ordinal.pred_zero
theorem succ_pred_iff_is_succ {o} : succ (pred o) = o ↔ ∃ a, o = succ a :=
⟨fun e => ⟨_, e.symm⟩, fun ⟨a, e⟩ => by simp only [e, pred_succ]⟩
#align ordinal.succ_pred_iff_is_succ Ordinal.succ_pred_iff_is_succ
theorem succ_lt_of_not_succ {o b : Ordinal} (h : ¬∃ a, o = succ a) : succ b < o ↔ b < o :=
⟨(lt_succ b).trans, fun l => lt_of_le_of_ne (succ_le_of_lt l) fun e => h ⟨_, e.symm⟩⟩
#align ordinal.succ_lt_of_not_succ Ordinal.succ_lt_of_not_succ
theorem lt_pred {a b} : a < pred b ↔ succ a < b :=
if h : ∃ a, b = succ a then by
let ⟨c, e⟩ := h
rw [e, pred_succ, succ_lt_succ_iff]
else by simp only [pred, dif_neg h, succ_lt_of_not_succ h]
#align ordinal.lt_pred Ordinal.lt_pred
theorem pred_le {a b} : pred a ≤ b ↔ a ≤ succ b :=
le_iff_le_iff_lt_iff_lt.2 lt_pred
#align ordinal.pred_le Ordinal.pred_le
@[simp]
theorem lift_is_succ {o : Ordinal.{v}} : (∃ a, lift.{u} o = succ a) ↔ ∃ a, o = succ a :=
⟨fun ⟨a, h⟩ =>
let ⟨b, e⟩ := lift_down <| show a ≤ lift.{u} o from le_of_lt <| h.symm ▸ lt_succ a
⟨b, lift_inj.1 <| by rw [h, ← e, lift_succ]⟩,
fun ⟨a, h⟩ => ⟨lift.{u} a, by simp only [h, lift_succ]⟩⟩
#align ordinal.lift_is_succ Ordinal.lift_is_succ
@[simp]
theorem lift_pred (o : Ordinal.{v}) : lift.{u} (pred o) = pred (lift.{u} o) :=
if h : ∃ a, o = succ a then by cases' h with a e; simp only [e, pred_succ, lift_succ]
else by rw [pred_eq_iff_not_succ.2 h, pred_eq_iff_not_succ.2 (mt lift_is_succ.1 h)]
#align ordinal.lift_pred Ordinal.lift_pred
def IsLimit (o : Ordinal) : Prop :=
o ≠ 0 ∧ ∀ a < o, succ a < o
#align ordinal.is_limit Ordinal.IsLimit
theorem IsLimit.isSuccLimit {o} (h : IsLimit o) : IsSuccLimit o := isSuccLimit_iff_succ_lt.mpr h.2
theorem IsLimit.succ_lt {o a : Ordinal} (h : IsLimit o) : a < o → succ a < o :=
h.2 a
#align ordinal.is_limit.succ_lt Ordinal.IsLimit.succ_lt
theorem isSuccLimit_zero : IsSuccLimit (0 : Ordinal) := isSuccLimit_bot
theorem not_zero_isLimit : ¬IsLimit 0
| ⟨h, _⟩ => h rfl
#align ordinal.not_zero_is_limit Ordinal.not_zero_isLimit
theorem not_succ_isLimit (o) : ¬IsLimit (succ o)
| ⟨_, h⟩ => lt_irrefl _ (h _ (lt_succ o))
#align ordinal.not_succ_is_limit Ordinal.not_succ_isLimit
theorem not_succ_of_isLimit {o} (h : IsLimit o) : ¬∃ a, o = succ a
| ⟨a, e⟩ => not_succ_isLimit a (e ▸ h)
#align ordinal.not_succ_of_is_limit Ordinal.not_succ_of_isLimit
theorem succ_lt_of_isLimit {o a : Ordinal} (h : IsLimit o) : succ a < o ↔ a < o :=
⟨(lt_succ a).trans, h.2 _⟩
#align ordinal.succ_lt_of_is_limit Ordinal.succ_lt_of_isLimit
theorem le_succ_of_isLimit {o} (h : IsLimit o) {a} : o ≤ succ a ↔ o ≤ a :=
le_iff_le_iff_lt_iff_lt.2 <| succ_lt_of_isLimit h
#align ordinal.le_succ_of_is_limit Ordinal.le_succ_of_isLimit
theorem limit_le {o} (h : IsLimit o) {a} : o ≤ a ↔ ∀ x < o, x ≤ a :=
⟨fun h _x l => l.le.trans h, fun H =>
(le_succ_of_isLimit h).1 <| le_of_not_lt fun hn => not_lt_of_le (H _ hn) (lt_succ a)⟩
#align ordinal.limit_le Ordinal.limit_le
theorem lt_limit {o} (h : IsLimit o) {a} : a < o ↔ ∃ x < o, a < x := by
-- Porting note: `bex_def` is required.
simpa only [not_forall₂, not_le, bex_def] using not_congr (@limit_le _ h a)
#align ordinal.lt_limit Ordinal.lt_limit
@[simp]
theorem lift_isLimit (o) : IsLimit (lift o) ↔ IsLimit o :=
and_congr (not_congr <| by simpa only [lift_zero] using @lift_inj o 0)
⟨fun H a h => lift_lt.1 <| by simpa only [lift_succ] using H _ (lift_lt.2 h), fun H a h => by
obtain ⟨a', rfl⟩ := lift_down h.le
rw [← lift_succ, lift_lt]
exact H a' (lift_lt.1 h)⟩
#align ordinal.lift_is_limit Ordinal.lift_isLimit
theorem IsLimit.pos {o : Ordinal} (h : IsLimit o) : 0 < o :=
lt_of_le_of_ne (Ordinal.zero_le _) h.1.symm
#align ordinal.is_limit.pos Ordinal.IsLimit.pos
theorem IsLimit.one_lt {o : Ordinal} (h : IsLimit o) : 1 < o := by
simpa only [succ_zero] using h.2 _ h.pos
#align ordinal.is_limit.one_lt Ordinal.IsLimit.one_lt
theorem IsLimit.nat_lt {o : Ordinal} (h : IsLimit o) : ∀ n : ℕ, (n : Ordinal) < o
| 0 => h.pos
| n + 1 => h.2 _ (IsLimit.nat_lt h n)
#align ordinal.is_limit.nat_lt Ordinal.IsLimit.nat_lt
theorem zero_or_succ_or_limit (o : Ordinal) : o = 0 ∨ (∃ a, o = succ a) ∨ IsLimit o :=
if o0 : o = 0 then Or.inl o0
else
if h : ∃ a, o = succ a then Or.inr (Or.inl h)
else Or.inr <| Or.inr ⟨o0, fun _a => (succ_lt_of_not_succ h).2⟩
#align ordinal.zero_or_succ_or_limit Ordinal.zero_or_succ_or_limit
@[elab_as_elim]
def limitRecOn {C : Ordinal → Sort*} (o : Ordinal) (H₁ : C 0) (H₂ : ∀ o, C o → C (succ o))
(H₃ : ∀ o, IsLimit o → (∀ o' < o, C o') → C o) : C o :=
SuccOrder.limitRecOn o (fun o _ ↦ H₂ o) fun o hl ↦
if h : o = 0 then fun _ ↦ h ▸ H₁ else H₃ o ⟨h, fun _ ↦ hl.succ_lt⟩
#align ordinal.limit_rec_on Ordinal.limitRecOn
@[simp]
theorem limitRecOn_zero {C} (H₁ H₂ H₃) : @limitRecOn C 0 H₁ H₂ H₃ = H₁ := by
rw [limitRecOn, SuccOrder.limitRecOn_limit _ _ isSuccLimit_zero, dif_pos rfl]
#align ordinal.limit_rec_on_zero Ordinal.limitRecOn_zero
@[simp]
theorem limitRecOn_succ {C} (o H₁ H₂ H₃) :
@limitRecOn C (succ o) H₁ H₂ H₃ = H₂ o (@limitRecOn C o H₁ H₂ H₃) := by
simp_rw [limitRecOn, SuccOrder.limitRecOn_succ _ _ (not_isMax _)]
#align ordinal.limit_rec_on_succ Ordinal.limitRecOn_succ
@[simp]
theorem limitRecOn_limit {C} (o H₁ H₂ H₃ h) :
@limitRecOn C o H₁ H₂ H₃ = H₃ o h fun x _h => @limitRecOn C x H₁ H₂ H₃ := by
simp_rw [limitRecOn, SuccOrder.limitRecOn_limit _ _ h.isSuccLimit, dif_neg h.1]
#align ordinal.limit_rec_on_limit Ordinal.limitRecOn_limit
instance orderTopOutSucc (o : Ordinal) : OrderTop (succ o).out.α :=
@OrderTop.mk _ _ (Top.mk _) le_enum_succ
#align ordinal.order_top_out_succ Ordinal.orderTopOutSucc
theorem enum_succ_eq_top {o : Ordinal} :
enum (· < ·) o
(by
rw [type_lt]
exact lt_succ o) =
(⊤ : (succ o).out.α) :=
rfl
#align ordinal.enum_succ_eq_top Ordinal.enum_succ_eq_top
theorem has_succ_of_type_succ_lt {α} {r : α → α → Prop} [wo : IsWellOrder α r]
(h : ∀ a < type r, succ a < type r) (x : α) : ∃ y, r x y := by
use enum r (succ (typein r x)) (h _ (typein_lt_type r x))
convert (enum_lt_enum (typein_lt_type r x)
(h _ (typein_lt_type r x))).mpr (lt_succ _); rw [enum_typein]
#align ordinal.has_succ_of_type_succ_lt Ordinal.has_succ_of_type_succ_lt
theorem out_no_max_of_succ_lt {o : Ordinal} (ho : ∀ a < o, succ a < o) : NoMaxOrder o.out.α :=
⟨has_succ_of_type_succ_lt (by rwa [type_lt])⟩
#align ordinal.out_no_max_of_succ_lt Ordinal.out_no_max_of_succ_lt
theorem bounded_singleton {r : α → α → Prop} [IsWellOrder α r] (hr : (type r).IsLimit) (x) :
Bounded r {x} := by
refine ⟨enum r (succ (typein r x)) (hr.2 _ (typein_lt_type r x)), ?_⟩
intro b hb
rw [mem_singleton_iff.1 hb]
nth_rw 1 [← enum_typein r x]
rw [@enum_lt_enum _ r]
apply lt_succ
#align ordinal.bounded_singleton Ordinal.bounded_singleton
-- Porting note: `· < ·` requires a type ascription for an `IsWellOrder` instance.
theorem type_subrel_lt (o : Ordinal.{u}) :
type (Subrel ((· < ·) : Ordinal → Ordinal → Prop) { o' : Ordinal | o' < o })
= Ordinal.lift.{u + 1} o := by
refine Quotient.inductionOn o ?_
rintro ⟨α, r, wo⟩; apply Quotient.sound
-- Porting note: `symm; refine' [term]` → `refine' [term].symm`
constructor; refine ((RelIso.preimage Equiv.ulift r).trans (enumIso r).symm).symm
#align ordinal.type_subrel_lt Ordinal.type_subrel_lt
theorem mk_initialSeg (o : Ordinal.{u}) :
#{ o' : Ordinal | o' < o } = Cardinal.lift.{u + 1} o.card := by
rw [lift_card, ← type_subrel_lt, card_type]
#align ordinal.mk_initial_seg Ordinal.mk_initialSeg
def IsNormal (f : Ordinal → Ordinal) : Prop :=
(∀ o, f o < f (succ o)) ∧ ∀ o, IsLimit o → ∀ a, f o ≤ a ↔ ∀ b < o, f b ≤ a
#align ordinal.is_normal Ordinal.IsNormal
theorem IsNormal.limit_le {f} (H : IsNormal f) :
∀ {o}, IsLimit o → ∀ {a}, f o ≤ a ↔ ∀ b < o, f b ≤ a :=
@H.2
#align ordinal.is_normal.limit_le Ordinal.IsNormal.limit_le
theorem IsNormal.limit_lt {f} (H : IsNormal f) {o} (h : IsLimit o) {a} :
a < f o ↔ ∃ b < o, a < f b :=
not_iff_not.1 <| by simpa only [exists_prop, not_exists, not_and, not_lt] using H.2 _ h a
#align ordinal.is_normal.limit_lt Ordinal.IsNormal.limit_lt
theorem IsNormal.strictMono {f} (H : IsNormal f) : StrictMono f := fun a b =>
limitRecOn b (Not.elim (not_lt_of_le <| Ordinal.zero_le _))
(fun _b IH h =>
(lt_or_eq_of_le (le_of_lt_succ h)).elim (fun h => (IH h).trans (H.1 _)) fun e => e ▸ H.1 _)
fun _b l _IH h => lt_of_lt_of_le (H.1 a) ((H.2 _ l _).1 le_rfl _ (l.2 _ h))
#align ordinal.is_normal.strict_mono Ordinal.IsNormal.strictMono
theorem IsNormal.monotone {f} (H : IsNormal f) : Monotone f :=
H.strictMono.monotone
#align ordinal.is_normal.monotone Ordinal.IsNormal.monotone
theorem isNormal_iff_strictMono_limit (f : Ordinal → Ordinal) :
IsNormal f ↔ StrictMono f ∧ ∀ o, IsLimit o → ∀ a, (∀ b < o, f b ≤ a) → f o ≤ a :=
⟨fun hf => ⟨hf.strictMono, fun a ha c => (hf.2 a ha c).2⟩, fun ⟨hs, hl⟩ =>
⟨fun a => hs (lt_succ a), fun a ha c =>
⟨fun hac _b hba => ((hs hba).trans_le hac).le, hl a ha c⟩⟩⟩
#align ordinal.is_normal_iff_strict_mono_limit Ordinal.isNormal_iff_strictMono_limit
theorem IsNormal.lt_iff {f} (H : IsNormal f) {a b} : f a < f b ↔ a < b :=
StrictMono.lt_iff_lt <| H.strictMono
#align ordinal.is_normal.lt_iff Ordinal.IsNormal.lt_iff
theorem IsNormal.le_iff {f} (H : IsNormal f) {a b} : f a ≤ f b ↔ a ≤ b :=
le_iff_le_iff_lt_iff_lt.2 H.lt_iff
#align ordinal.is_normal.le_iff Ordinal.IsNormal.le_iff
theorem IsNormal.inj {f} (H : IsNormal f) {a b} : f a = f b ↔ a = b := by
simp only [le_antisymm_iff, H.le_iff]
#align ordinal.is_normal.inj Ordinal.IsNormal.inj
theorem IsNormal.self_le {f} (H : IsNormal f) (a) : a ≤ f a :=
lt_wf.self_le_of_strictMono H.strictMono a
#align ordinal.is_normal.self_le Ordinal.IsNormal.self_le
theorem IsNormal.le_set {f o} (H : IsNormal f) (p : Set Ordinal) (p0 : p.Nonempty) (b)
(H₂ : ∀ o, b ≤ o ↔ ∀ a ∈ p, a ≤ o) : f b ≤ o ↔ ∀ a ∈ p, f a ≤ o :=
⟨fun h a pa => (H.le_iff.2 ((H₂ _).1 le_rfl _ pa)).trans h, fun h => by
-- Porting note: `refine'` didn't work well so `induction` is used
induction b using limitRecOn with
| H₁ =>
cases' p0 with x px
have := Ordinal.le_zero.1 ((H₂ _).1 (Ordinal.zero_le _) _ px)
rw [this] at px
exact h _ px
| H₂ S _ =>
rcases not_forall₂.1 (mt (H₂ S).2 <| (lt_succ S).not_le) with ⟨a, h₁, h₂⟩
exact (H.le_iff.2 <| succ_le_of_lt <| not_le.1 h₂).trans (h _ h₁)
| H₃ S L _ =>
refine (H.2 _ L _).2 fun a h' => ?_
rcases not_forall₂.1 (mt (H₂ a).2 h'.not_le) with ⟨b, h₁, h₂⟩
exact (H.le_iff.2 <| (not_le.1 h₂).le).trans (h _ h₁)⟩
#align ordinal.is_normal.le_set Ordinal.IsNormal.le_set
theorem IsNormal.le_set' {f o} (H : IsNormal f) (p : Set α) (p0 : p.Nonempty) (g : α → Ordinal) (b)
(H₂ : ∀ o, b ≤ o ↔ ∀ a ∈ p, g a ≤ o) : f b ≤ o ↔ ∀ a ∈ p, f (g a) ≤ o := by
simpa [H₂] using H.le_set (g '' p) (p0.image g) b
#align ordinal.is_normal.le_set' Ordinal.IsNormal.le_set'
theorem IsNormal.refl : IsNormal id :=
⟨lt_succ, fun _o l _a => Ordinal.limit_le l⟩
#align ordinal.is_normal.refl Ordinal.IsNormal.refl
theorem IsNormal.trans {f g} (H₁ : IsNormal f) (H₂ : IsNormal g) : IsNormal (f ∘ g) :=
⟨fun _x => H₁.lt_iff.2 (H₂.1 _), fun o l _a =>
H₁.le_set' (· < o) ⟨0, l.pos⟩ g _ fun _c => H₂.2 _ l _⟩
#align ordinal.is_normal.trans Ordinal.IsNormal.trans
theorem IsNormal.isLimit {f} (H : IsNormal f) {o} (l : IsLimit o) : IsLimit (f o) :=
⟨ne_of_gt <| (Ordinal.zero_le _).trans_lt <| H.lt_iff.2 l.pos, fun _ h =>
let ⟨_b, h₁, h₂⟩ := (H.limit_lt l).1 h
(succ_le_of_lt h₂).trans_lt (H.lt_iff.2 h₁)⟩
#align ordinal.is_normal.is_limit Ordinal.IsNormal.isLimit
theorem IsNormal.le_iff_eq {f} (H : IsNormal f) {a} : f a ≤ a ↔ f a = a :=
(H.self_le a).le_iff_eq
#align ordinal.is_normal.le_iff_eq Ordinal.IsNormal.le_iff_eq
theorem add_le_of_limit {a b c : Ordinal} (h : IsLimit b) : a + b ≤ c ↔ ∀ b' < b, a + b' ≤ c :=
⟨fun h b' l => (add_le_add_left l.le _).trans h, fun H =>
le_of_not_lt <| by
-- Porting note: `induction` tactics are required because of the parser bug.
induction a using inductionOn with
| H α r =>
induction b using inductionOn with
| H β s =>
intro l
suffices ∀ x : β, Sum.Lex r s (Sum.inr x) (enum _ _ l) by
-- Porting note: `revert` & `intro` is required because `cases'` doesn't replace
-- `enum _ _ l` in `this`.
revert this; cases' enum _ _ l with x x <;> intro this
· cases this (enum s 0 h.pos)
· exact irrefl _ (this _)
intro x
rw [← typein_lt_typein (Sum.Lex r s), typein_enum]
have := H _ (h.2 _ (typein_lt_type s x))
rw [add_succ, succ_le_iff] at this
refine
(RelEmbedding.ofMonotone (fun a => ?_) fun a b => ?_).ordinal_type_le.trans_lt this
· rcases a with ⟨a | b, h⟩
· exact Sum.inl a
· exact Sum.inr ⟨b, by cases h; assumption⟩
· rcases a with ⟨a | a, h₁⟩ <;> rcases b with ⟨b | b, h₂⟩ <;> cases h₁ <;> cases h₂ <;>
rintro ⟨⟩ <;> constructor <;> assumption⟩
#align ordinal.add_le_of_limit Ordinal.add_le_of_limit
theorem add_isNormal (a : Ordinal) : IsNormal (a + ·) :=
⟨fun b => (add_lt_add_iff_left a).2 (lt_succ b), fun _b l _c => add_le_of_limit l⟩
#align ordinal.add_is_normal Ordinal.add_isNormal
theorem add_isLimit (a) {b} : IsLimit b → IsLimit (a + b) :=
(add_isNormal a).isLimit
#align ordinal.add_is_limit Ordinal.add_isLimit
alias IsLimit.add := add_isLimit
#align ordinal.is_limit.add Ordinal.IsLimit.add
theorem sub_nonempty {a b : Ordinal} : { o | a ≤ b + o }.Nonempty :=
⟨a, le_add_left _ _⟩
#align ordinal.sub_nonempty Ordinal.sub_nonempty
instance sub : Sub Ordinal :=
⟨fun a b => sInf { o | a ≤ b + o }⟩
theorem le_add_sub (a b : Ordinal) : a ≤ b + (a - b) :=
csInf_mem sub_nonempty
#align ordinal.le_add_sub Ordinal.le_add_sub
theorem sub_le {a b c : Ordinal} : a - b ≤ c ↔ a ≤ b + c :=
⟨fun h => (le_add_sub a b).trans (add_le_add_left h _), fun h => csInf_le' h⟩
#align ordinal.sub_le Ordinal.sub_le
theorem lt_sub {a b c : Ordinal} : a < b - c ↔ c + a < b :=
lt_iff_lt_of_le_iff_le sub_le
#align ordinal.lt_sub Ordinal.lt_sub
theorem add_sub_cancel (a b : Ordinal) : a + b - a = b :=
le_antisymm (sub_le.2 <| le_rfl) ((add_le_add_iff_left a).1 <| le_add_sub _ _)
#align ordinal.add_sub_cancel Ordinal.add_sub_cancel
theorem sub_eq_of_add_eq {a b c : Ordinal} (h : a + b = c) : c - a = b :=
h ▸ add_sub_cancel _ _
#align ordinal.sub_eq_of_add_eq Ordinal.sub_eq_of_add_eq
theorem sub_le_self (a b : Ordinal) : a - b ≤ a :=
sub_le.2 <| le_add_left _ _
#align ordinal.sub_le_self Ordinal.sub_le_self
protected theorem add_sub_cancel_of_le {a b : Ordinal} (h : b ≤ a) : b + (a - b) = a :=
(le_add_sub a b).antisymm'
(by
rcases zero_or_succ_or_limit (a - b) with (e | ⟨c, e⟩ | l)
· simp only [e, add_zero, h]
· rw [e, add_succ, succ_le_iff, ← lt_sub, e]
exact lt_succ c
· exact (add_le_of_limit l).2 fun c l => (lt_sub.1 l).le)
#align ordinal.add_sub_cancel_of_le Ordinal.add_sub_cancel_of_le
theorem le_sub_of_le {a b c : Ordinal} (h : b ≤ a) : c ≤ a - b ↔ b + c ≤ a := by
rw [← add_le_add_iff_left b, Ordinal.add_sub_cancel_of_le h]
#align ordinal.le_sub_of_le Ordinal.le_sub_of_le
theorem sub_lt_of_le {a b c : Ordinal} (h : b ≤ a) : a - b < c ↔ a < b + c :=
lt_iff_lt_of_le_iff_le (le_sub_of_le h)
#align ordinal.sub_lt_of_le Ordinal.sub_lt_of_le
instance existsAddOfLE : ExistsAddOfLE Ordinal :=
⟨fun h => ⟨_, (Ordinal.add_sub_cancel_of_le h).symm⟩⟩
@[simp]
theorem sub_zero (a : Ordinal) : a - 0 = a := by simpa only [zero_add] using add_sub_cancel 0 a
#align ordinal.sub_zero Ordinal.sub_zero
@[simp]
theorem zero_sub (a : Ordinal) : 0 - a = 0 := by rw [← Ordinal.le_zero]; apply sub_le_self
#align ordinal.zero_sub Ordinal.zero_sub
@[simp]
theorem sub_self (a : Ordinal) : a - a = 0 := by simpa only [add_zero] using add_sub_cancel a 0
#align ordinal.sub_self Ordinal.sub_self
protected theorem sub_eq_zero_iff_le {a b : Ordinal} : a - b = 0 ↔ a ≤ b :=
⟨fun h => by simpa only [h, add_zero] using le_add_sub a b, fun h => by
rwa [← Ordinal.le_zero, sub_le, add_zero]⟩
#align ordinal.sub_eq_zero_iff_le Ordinal.sub_eq_zero_iff_le
theorem sub_sub (a b c : Ordinal) : a - b - c = a - (b + c) :=
eq_of_forall_ge_iff fun d => by rw [sub_le, sub_le, sub_le, add_assoc]
#align ordinal.sub_sub Ordinal.sub_sub
@[simp]
theorem add_sub_add_cancel (a b c : Ordinal) : a + b - (a + c) = b - c := by
rw [← sub_sub, add_sub_cancel]
#align ordinal.add_sub_add_cancel Ordinal.add_sub_add_cancel
theorem sub_isLimit {a b} (l : IsLimit a) (h : b < a) : IsLimit (a - b) :=
⟨ne_of_gt <| lt_sub.2 <| by rwa [add_zero], fun c h => by
rw [lt_sub, add_succ]; exact l.2 _ (lt_sub.1 h)⟩
#align ordinal.sub_is_limit Ordinal.sub_isLimit
-- @[simp] -- Porting note (#10618): simp can prove this
theorem one_add_omega : 1 + ω = ω := by
refine le_antisymm ?_ (le_add_left _ _)
rw [omega, ← lift_one.{_, 0}, ← lift_add, lift_le, ← type_unit, ← type_sum_lex]
refine ⟨RelEmbedding.collapse (RelEmbedding.ofMonotone ?_ ?_)⟩
· apply Sum.rec
· exact fun _ => 0
· exact Nat.succ
· intro a b
cases a <;> cases b <;> intro H <;> cases' H with _ _ H _ _ H <;>
[exact H.elim; exact Nat.succ_pos _; exact Nat.succ_lt_succ H]
#align ordinal.one_add_omega Ordinal.one_add_omega
@[simp]
| Mathlib/SetTheory/Ordinal/Arithmetic.lean | 625 | 626 | theorem one_add_of_omega_le {o} (h : ω ≤ o) : 1 + o = o := by |
rw [← Ordinal.add_sub_cancel_of_le h, ← add_assoc, one_add_omega]
|
import Mathlib.Data.Fintype.Option
import Mathlib.Data.Fintype.Prod
import Mathlib.Data.Fintype.Pi
import Mathlib.Data.Vector.Basic
import Mathlib.Data.PFun
import Mathlib.Logic.Function.Iterate
import Mathlib.Order.Basic
import Mathlib.Tactic.ApplyFun
#align_import computability.turing_machine from "leanprover-community/mathlib"@"4c19a16e4b705bf135cf9a80ac18fcc99c438514"
assert_not_exists MonoidWithZero
open Relation
open Nat (iterate)
open Function (update iterate_succ iterate_succ_apply iterate_succ' iterate_succ_apply'
iterate_zero_apply)
namespace Turing
def BlankExtends {Γ} [Inhabited Γ] (l₁ l₂ : List Γ) : Prop :=
∃ n, l₂ = l₁ ++ List.replicate n default
#align turing.blank_extends Turing.BlankExtends
@[refl]
theorem BlankExtends.refl {Γ} [Inhabited Γ] (l : List Γ) : BlankExtends l l :=
⟨0, by simp⟩
#align turing.blank_extends.refl Turing.BlankExtends.refl
@[trans]
theorem BlankExtends.trans {Γ} [Inhabited Γ] {l₁ l₂ l₃ : List Γ} :
BlankExtends l₁ l₂ → BlankExtends l₂ l₃ → BlankExtends l₁ l₃ := by
rintro ⟨i, rfl⟩ ⟨j, rfl⟩
exact ⟨i + j, by simp [List.replicate_add]⟩
#align turing.blank_extends.trans Turing.BlankExtends.trans
theorem BlankExtends.below_of_le {Γ} [Inhabited Γ] {l l₁ l₂ : List Γ} :
BlankExtends l l₁ → BlankExtends l l₂ → l₁.length ≤ l₂.length → BlankExtends l₁ l₂ := by
rintro ⟨i, rfl⟩ ⟨j, rfl⟩ h; use j - i
simp only [List.length_append, Nat.add_le_add_iff_left, List.length_replicate] at h
simp only [← List.replicate_add, Nat.add_sub_cancel' h, List.append_assoc]
#align turing.blank_extends.below_of_le Turing.BlankExtends.below_of_le
def BlankExtends.above {Γ} [Inhabited Γ] {l l₁ l₂ : List Γ} (h₁ : BlankExtends l l₁)
(h₂ : BlankExtends l l₂) : { l' // BlankExtends l₁ l' ∧ BlankExtends l₂ l' } :=
if h : l₁.length ≤ l₂.length then ⟨l₂, h₁.below_of_le h₂ h, BlankExtends.refl _⟩
else ⟨l₁, BlankExtends.refl _, h₂.below_of_le h₁ (le_of_not_ge h)⟩
#align turing.blank_extends.above Turing.BlankExtends.above
theorem BlankExtends.above_of_le {Γ} [Inhabited Γ] {l l₁ l₂ : List Γ} :
BlankExtends l₁ l → BlankExtends l₂ l → l₁.length ≤ l₂.length → BlankExtends l₁ l₂ := by
rintro ⟨i, rfl⟩ ⟨j, e⟩ h; use i - j
refine List.append_cancel_right (e.symm.trans ?_)
rw [List.append_assoc, ← List.replicate_add, Nat.sub_add_cancel]
apply_fun List.length at e
simp only [List.length_append, List.length_replicate] at e
rwa [← Nat.add_le_add_iff_left, e, Nat.add_le_add_iff_right]
#align turing.blank_extends.above_of_le Turing.BlankExtends.above_of_le
def BlankRel {Γ} [Inhabited Γ] (l₁ l₂ : List Γ) : Prop :=
BlankExtends l₁ l₂ ∨ BlankExtends l₂ l₁
#align turing.blank_rel Turing.BlankRel
@[refl]
theorem BlankRel.refl {Γ} [Inhabited Γ] (l : List Γ) : BlankRel l l :=
Or.inl (BlankExtends.refl _)
#align turing.blank_rel.refl Turing.BlankRel.refl
@[symm]
theorem BlankRel.symm {Γ} [Inhabited Γ] {l₁ l₂ : List Γ} : BlankRel l₁ l₂ → BlankRel l₂ l₁ :=
Or.symm
#align turing.blank_rel.symm Turing.BlankRel.symm
@[trans]
theorem BlankRel.trans {Γ} [Inhabited Γ] {l₁ l₂ l₃ : List Γ} :
BlankRel l₁ l₂ → BlankRel l₂ l₃ → BlankRel l₁ l₃ := by
rintro (h₁ | h₁) (h₂ | h₂)
· exact Or.inl (h₁.trans h₂)
· rcases le_total l₁.length l₃.length with h | h
· exact Or.inl (h₁.above_of_le h₂ h)
· exact Or.inr (h₂.above_of_le h₁ h)
· rcases le_total l₁.length l₃.length with h | h
· exact Or.inl (h₁.below_of_le h₂ h)
· exact Or.inr (h₂.below_of_le h₁ h)
· exact Or.inr (h₂.trans h₁)
#align turing.blank_rel.trans Turing.BlankRel.trans
def BlankRel.above {Γ} [Inhabited Γ] {l₁ l₂ : List Γ} (h : BlankRel l₁ l₂) :
{ l // BlankExtends l₁ l ∧ BlankExtends l₂ l } := by
refine
if hl : l₁.length ≤ l₂.length then ⟨l₂, Or.elim h id fun h' ↦ ?_, BlankExtends.refl _⟩
else ⟨l₁, BlankExtends.refl _, Or.elim h (fun h' ↦ ?_) id⟩
· exact (BlankExtends.refl _).above_of_le h' hl
· exact (BlankExtends.refl _).above_of_le h' (le_of_not_ge hl)
#align turing.blank_rel.above Turing.BlankRel.above
def BlankRel.below {Γ} [Inhabited Γ] {l₁ l₂ : List Γ} (h : BlankRel l₁ l₂) :
{ l // BlankExtends l l₁ ∧ BlankExtends l l₂ } := by
refine
if hl : l₁.length ≤ l₂.length then ⟨l₁, BlankExtends.refl _, Or.elim h id fun h' ↦ ?_⟩
else ⟨l₂, Or.elim h (fun h' ↦ ?_) id, BlankExtends.refl _⟩
· exact (BlankExtends.refl _).above_of_le h' hl
· exact (BlankExtends.refl _).above_of_le h' (le_of_not_ge hl)
#align turing.blank_rel.below Turing.BlankRel.below
theorem BlankRel.equivalence (Γ) [Inhabited Γ] : Equivalence (@BlankRel Γ _) :=
⟨BlankRel.refl, @BlankRel.symm _ _, @BlankRel.trans _ _⟩
#align turing.blank_rel.equivalence Turing.BlankRel.equivalence
def BlankRel.setoid (Γ) [Inhabited Γ] : Setoid (List Γ) :=
⟨_, BlankRel.equivalence _⟩
#align turing.blank_rel.setoid Turing.BlankRel.setoid
def ListBlank (Γ) [Inhabited Γ] :=
Quotient (BlankRel.setoid Γ)
#align turing.list_blank Turing.ListBlank
instance ListBlank.inhabited {Γ} [Inhabited Γ] : Inhabited (ListBlank Γ) :=
⟨Quotient.mk'' []⟩
#align turing.list_blank.inhabited Turing.ListBlank.inhabited
instance ListBlank.hasEmptyc {Γ} [Inhabited Γ] : EmptyCollection (ListBlank Γ) :=
⟨Quotient.mk'' []⟩
#align turing.list_blank.has_emptyc Turing.ListBlank.hasEmptyc
-- Porting note: Removed `@[elab_as_elim]`
protected abbrev ListBlank.liftOn {Γ} [Inhabited Γ] {α} (l : ListBlank Γ) (f : List Γ → α)
(H : ∀ a b, BlankExtends a b → f a = f b) : α :=
l.liftOn' f <| by rintro a b (h | h) <;> [exact H _ _ h; exact (H _ _ h).symm]
#align turing.list_blank.lift_on Turing.ListBlank.liftOn
def ListBlank.mk {Γ} [Inhabited Γ] : List Γ → ListBlank Γ :=
Quotient.mk''
#align turing.list_blank.mk Turing.ListBlank.mk
@[elab_as_elim]
protected theorem ListBlank.induction_on {Γ} [Inhabited Γ] {p : ListBlank Γ → Prop}
(q : ListBlank Γ) (h : ∀ a, p (ListBlank.mk a)) : p q :=
Quotient.inductionOn' q h
#align turing.list_blank.induction_on Turing.ListBlank.induction_on
def ListBlank.head {Γ} [Inhabited Γ] (l : ListBlank Γ) : Γ := by
apply l.liftOn List.headI
rintro a _ ⟨i, rfl⟩
cases a
· cases i <;> rfl
rfl
#align turing.list_blank.head Turing.ListBlank.head
@[simp]
theorem ListBlank.head_mk {Γ} [Inhabited Γ] (l : List Γ) :
ListBlank.head (ListBlank.mk l) = l.headI :=
rfl
#align turing.list_blank.head_mk Turing.ListBlank.head_mk
def ListBlank.tail {Γ} [Inhabited Γ] (l : ListBlank Γ) : ListBlank Γ := by
apply l.liftOn (fun l ↦ ListBlank.mk l.tail)
rintro a _ ⟨i, rfl⟩
refine Quotient.sound' (Or.inl ?_)
cases a
· cases' i with i <;> [exact ⟨0, rfl⟩; exact ⟨i, rfl⟩]
exact ⟨i, rfl⟩
#align turing.list_blank.tail Turing.ListBlank.tail
@[simp]
theorem ListBlank.tail_mk {Γ} [Inhabited Γ] (l : List Γ) :
ListBlank.tail (ListBlank.mk l) = ListBlank.mk l.tail :=
rfl
#align turing.list_blank.tail_mk Turing.ListBlank.tail_mk
def ListBlank.cons {Γ} [Inhabited Γ] (a : Γ) (l : ListBlank Γ) : ListBlank Γ := by
apply l.liftOn (fun l ↦ ListBlank.mk (List.cons a l))
rintro _ _ ⟨i, rfl⟩
exact Quotient.sound' (Or.inl ⟨i, rfl⟩)
#align turing.list_blank.cons Turing.ListBlank.cons
@[simp]
theorem ListBlank.cons_mk {Γ} [Inhabited Γ] (a : Γ) (l : List Γ) :
ListBlank.cons a (ListBlank.mk l) = ListBlank.mk (a :: l) :=
rfl
#align turing.list_blank.cons_mk Turing.ListBlank.cons_mk
@[simp]
theorem ListBlank.head_cons {Γ} [Inhabited Γ] (a : Γ) : ∀ l : ListBlank Γ, (l.cons a).head = a :=
Quotient.ind' fun _ ↦ rfl
#align turing.list_blank.head_cons Turing.ListBlank.head_cons
@[simp]
theorem ListBlank.tail_cons {Γ} [Inhabited Γ] (a : Γ) : ∀ l : ListBlank Γ, (l.cons a).tail = l :=
Quotient.ind' fun _ ↦ rfl
#align turing.list_blank.tail_cons Turing.ListBlank.tail_cons
@[simp]
theorem ListBlank.cons_head_tail {Γ} [Inhabited Γ] : ∀ l : ListBlank Γ, l.tail.cons l.head = l := by
apply Quotient.ind'
refine fun l ↦ Quotient.sound' (Or.inr ?_)
cases l
· exact ⟨1, rfl⟩
· rfl
#align turing.list_blank.cons_head_tail Turing.ListBlank.cons_head_tail
theorem ListBlank.exists_cons {Γ} [Inhabited Γ] (l : ListBlank Γ) :
∃ a l', l = ListBlank.cons a l' :=
⟨_, _, (ListBlank.cons_head_tail _).symm⟩
#align turing.list_blank.exists_cons Turing.ListBlank.exists_cons
def ListBlank.nth {Γ} [Inhabited Γ] (l : ListBlank Γ) (n : ℕ) : Γ := by
apply l.liftOn (fun l ↦ List.getI l n)
rintro l _ ⟨i, rfl⟩
cases' lt_or_le n _ with h h
· rw [List.getI_append _ _ _ h]
rw [List.getI_eq_default _ h]
rcases le_or_lt _ n with h₂ | h₂
· rw [List.getI_eq_default _ h₂]
rw [List.getI_eq_get _ h₂, List.get_append_right' h, List.get_replicate]
#align turing.list_blank.nth Turing.ListBlank.nth
@[simp]
theorem ListBlank.nth_mk {Γ} [Inhabited Γ] (l : List Γ) (n : ℕ) :
(ListBlank.mk l).nth n = l.getI n :=
rfl
#align turing.list_blank.nth_mk Turing.ListBlank.nth_mk
@[simp]
theorem ListBlank.nth_zero {Γ} [Inhabited Γ] (l : ListBlank Γ) : l.nth 0 = l.head := by
conv => lhs; rw [← ListBlank.cons_head_tail l]
exact Quotient.inductionOn' l.tail fun l ↦ rfl
#align turing.list_blank.nth_zero Turing.ListBlank.nth_zero
@[simp]
theorem ListBlank.nth_succ {Γ} [Inhabited Γ] (l : ListBlank Γ) (n : ℕ) :
l.nth (n + 1) = l.tail.nth n := by
conv => lhs; rw [← ListBlank.cons_head_tail l]
exact Quotient.inductionOn' l.tail fun l ↦ rfl
#align turing.list_blank.nth_succ Turing.ListBlank.nth_succ
@[ext]
theorem ListBlank.ext {Γ} [i : Inhabited Γ] {L₁ L₂ : ListBlank Γ} :
(∀ i, L₁.nth i = L₂.nth i) → L₁ = L₂ := by
refine ListBlank.induction_on L₁ fun l₁ ↦ ListBlank.induction_on L₂ fun l₂ H ↦ ?_
wlog h : l₁.length ≤ l₂.length
· cases le_total l₁.length l₂.length <;> [skip; symm] <;> apply this <;> try assumption
intro
rw [H]
refine Quotient.sound' (Or.inl ⟨l₂.length - l₁.length, ?_⟩)
refine List.ext_get ?_ fun i h h₂ ↦ Eq.symm ?_
· simp only [Nat.add_sub_cancel' h, List.length_append, List.length_replicate]
simp only [ListBlank.nth_mk] at H
cases' lt_or_le i l₁.length with h' h'
· simp only [List.get_append _ h', List.get?_eq_get h, List.get?_eq_get h',
← List.getI_eq_get _ h, ← List.getI_eq_get _ h', H]
· simp only [List.get_append_right' h', List.get_replicate, List.get?_eq_get h,
List.get?_len_le h', ← List.getI_eq_default _ h', H, List.getI_eq_get _ h]
#align turing.list_blank.ext Turing.ListBlank.ext
@[simp]
def ListBlank.modifyNth {Γ} [Inhabited Γ] (f : Γ → Γ) : ℕ → ListBlank Γ → ListBlank Γ
| 0, L => L.tail.cons (f L.head)
| n + 1, L => (L.tail.modifyNth f n).cons L.head
#align turing.list_blank.modify_nth Turing.ListBlank.modifyNth
theorem ListBlank.nth_modifyNth {Γ} [Inhabited Γ] (f : Γ → Γ) (n i) (L : ListBlank Γ) :
(L.modifyNth f n).nth i = if i = n then f (L.nth i) else L.nth i := by
induction' n with n IH generalizing i L
· cases i <;> simp only [ListBlank.nth_zero, if_true, ListBlank.head_cons, ListBlank.modifyNth,
ListBlank.nth_succ, if_false, ListBlank.tail_cons, Nat.zero_eq]
· cases i
· rw [if_neg (Nat.succ_ne_zero _).symm]
simp only [ListBlank.nth_zero, ListBlank.head_cons, ListBlank.modifyNth, Nat.zero_eq]
· simp only [IH, ListBlank.modifyNth, ListBlank.nth_succ, ListBlank.tail_cons, Nat.succ.injEq]
#align turing.list_blank.nth_modify_nth Turing.ListBlank.nth_modifyNth
structure PointedMap.{u, v} (Γ : Type u) (Γ' : Type v) [Inhabited Γ] [Inhabited Γ'] :
Type max u v where
f : Γ → Γ'
map_pt' : f default = default
#align turing.pointed_map Turing.PointedMap
instance {Γ Γ'} [Inhabited Γ] [Inhabited Γ'] : Inhabited (PointedMap Γ Γ') :=
⟨⟨default, rfl⟩⟩
instance {Γ Γ'} [Inhabited Γ] [Inhabited Γ'] : CoeFun (PointedMap Γ Γ') fun _ ↦ Γ → Γ' :=
⟨PointedMap.f⟩
-- @[simp] -- Porting note (#10685): dsimp can prove this
theorem PointedMap.mk_val {Γ Γ'} [Inhabited Γ] [Inhabited Γ'] (f : Γ → Γ') (pt) :
(PointedMap.mk f pt : Γ → Γ') = f :=
rfl
#align turing.pointed_map.mk_val Turing.PointedMap.mk_val
@[simp]
theorem PointedMap.map_pt {Γ Γ'} [Inhabited Γ] [Inhabited Γ'] (f : PointedMap Γ Γ') :
f default = default :=
PointedMap.map_pt' _
#align turing.pointed_map.map_pt Turing.PointedMap.map_pt
@[simp]
theorem PointedMap.headI_map {Γ Γ'} [Inhabited Γ] [Inhabited Γ'] (f : PointedMap Γ Γ')
(l : List Γ) : (l.map f).headI = f l.headI := by
cases l <;> [exact (PointedMap.map_pt f).symm; rfl]
#align turing.pointed_map.head_map Turing.PointedMap.headI_map
def ListBlank.map {Γ Γ'} [Inhabited Γ] [Inhabited Γ'] (f : PointedMap Γ Γ') (l : ListBlank Γ) :
ListBlank Γ' := by
apply l.liftOn (fun l ↦ ListBlank.mk (List.map f l))
rintro l _ ⟨i, rfl⟩; refine Quotient.sound' (Or.inl ⟨i, ?_⟩)
simp only [PointedMap.map_pt, List.map_append, List.map_replicate]
#align turing.list_blank.map Turing.ListBlank.map
@[simp]
theorem ListBlank.map_mk {Γ Γ'} [Inhabited Γ] [Inhabited Γ'] (f : PointedMap Γ Γ') (l : List Γ) :
(ListBlank.mk l).map f = ListBlank.mk (l.map f) :=
rfl
#align turing.list_blank.map_mk Turing.ListBlank.map_mk
@[simp]
theorem ListBlank.head_map {Γ Γ'} [Inhabited Γ] [Inhabited Γ'] (f : PointedMap Γ Γ')
(l : ListBlank Γ) : (l.map f).head = f l.head := by
conv => lhs; rw [← ListBlank.cons_head_tail l]
exact Quotient.inductionOn' l fun a ↦ rfl
#align turing.list_blank.head_map Turing.ListBlank.head_map
@[simp]
theorem ListBlank.tail_map {Γ Γ'} [Inhabited Γ] [Inhabited Γ'] (f : PointedMap Γ Γ')
(l : ListBlank Γ) : (l.map f).tail = l.tail.map f := by
conv => lhs; rw [← ListBlank.cons_head_tail l]
exact Quotient.inductionOn' l fun a ↦ rfl
#align turing.list_blank.tail_map Turing.ListBlank.tail_map
@[simp]
theorem ListBlank.map_cons {Γ Γ'} [Inhabited Γ] [Inhabited Γ'] (f : PointedMap Γ Γ')
(l : ListBlank Γ) (a : Γ) : (l.cons a).map f = (l.map f).cons (f a) := by
refine (ListBlank.cons_head_tail _).symm.trans ?_
simp only [ListBlank.head_map, ListBlank.head_cons, ListBlank.tail_map, ListBlank.tail_cons]
#align turing.list_blank.map_cons Turing.ListBlank.map_cons
@[simp]
theorem ListBlank.nth_map {Γ Γ'} [Inhabited Γ] [Inhabited Γ'] (f : PointedMap Γ Γ')
(l : ListBlank Γ) (n : ℕ) : (l.map f).nth n = f (l.nth n) := by
refine l.inductionOn fun l ↦ ?_
-- Porting note: Added `suffices` to get `simp` to work.
suffices ((mk l).map f).nth n = f ((mk l).nth n) by exact this
simp only [List.get?_map, ListBlank.map_mk, ListBlank.nth_mk, List.getI_eq_iget_get?]
cases l.get? n
· exact f.2.symm
· rfl
#align turing.list_blank.nth_map Turing.ListBlank.nth_map
def proj {ι : Type*} {Γ : ι → Type*} [∀ i, Inhabited (Γ i)] (i : ι) :
PointedMap (∀ i, Γ i) (Γ i) :=
⟨fun a ↦ a i, rfl⟩
#align turing.proj Turing.proj
theorem proj_map_nth {ι : Type*} {Γ : ι → Type*} [∀ i, Inhabited (Γ i)] (i : ι) (L n) :
(ListBlank.map (@proj ι Γ _ i) L).nth n = L.nth n i := by
rw [ListBlank.nth_map]; rfl
#align turing.proj_map_nth Turing.proj_map_nth
theorem ListBlank.map_modifyNth {Γ Γ'} [Inhabited Γ] [Inhabited Γ'] (F : PointedMap Γ Γ')
(f : Γ → Γ) (f' : Γ' → Γ') (H : ∀ x, F (f x) = f' (F x)) (n) (L : ListBlank Γ) :
(L.modifyNth f n).map F = (L.map F).modifyNth f' n := by
induction' n with n IH generalizing L <;>
simp only [*, ListBlank.head_map, ListBlank.modifyNth, ListBlank.map_cons, ListBlank.tail_map]
#align turing.list_blank.map_modify_nth Turing.ListBlank.map_modifyNth
@[simp]
def ListBlank.append {Γ} [Inhabited Γ] : List Γ → ListBlank Γ → ListBlank Γ
| [], L => L
| a :: l, L => ListBlank.cons a (ListBlank.append l L)
#align turing.list_blank.append Turing.ListBlank.append
@[simp]
theorem ListBlank.append_mk {Γ} [Inhabited Γ] (l₁ l₂ : List Γ) :
ListBlank.append l₁ (ListBlank.mk l₂) = ListBlank.mk (l₁ ++ l₂) := by
induction l₁ <;>
simp only [*, ListBlank.append, List.nil_append, List.cons_append, ListBlank.cons_mk]
#align turing.list_blank.append_mk Turing.ListBlank.append_mk
theorem ListBlank.append_assoc {Γ} [Inhabited Γ] (l₁ l₂ : List Γ) (l₃ : ListBlank Γ) :
ListBlank.append (l₁ ++ l₂) l₃ = ListBlank.append l₁ (ListBlank.append l₂ l₃) := by
refine l₃.inductionOn fun l ↦ ?_
-- Porting note: Added `suffices` to get `simp` to work.
suffices append (l₁ ++ l₂) (mk l) = append l₁ (append l₂ (mk l)) by exact this
simp only [ListBlank.append_mk, List.append_assoc]
#align turing.list_blank.append_assoc Turing.ListBlank.append_assoc
def ListBlank.bind {Γ Γ'} [Inhabited Γ] [Inhabited Γ'] (l : ListBlank Γ) (f : Γ → List Γ')
(hf : ∃ n, f default = List.replicate n default) : ListBlank Γ' := by
apply l.liftOn (fun l ↦ ListBlank.mk (List.bind l f))
rintro l _ ⟨i, rfl⟩; cases' hf with n e; refine Quotient.sound' (Or.inl ⟨i * n, ?_⟩)
rw [List.append_bind, mul_comm]; congr
induction' i with i IH
· rfl
simp only [IH, e, List.replicate_add, Nat.mul_succ, add_comm, List.replicate_succ, List.cons_bind]
#align turing.list_blank.bind Turing.ListBlank.bind
@[simp]
theorem ListBlank.bind_mk {Γ Γ'} [Inhabited Γ] [Inhabited Γ'] (l : List Γ) (f : Γ → List Γ') (hf) :
(ListBlank.mk l).bind f hf = ListBlank.mk (l.bind f) :=
rfl
#align turing.list_blank.bind_mk Turing.ListBlank.bind_mk
@[simp]
theorem ListBlank.cons_bind {Γ Γ'} [Inhabited Γ] [Inhabited Γ'] (a : Γ) (l : ListBlank Γ)
(f : Γ → List Γ') (hf) : (l.cons a).bind f hf = (l.bind f hf).append (f a) := by
refine l.inductionOn fun l ↦ ?_
-- Porting note: Added `suffices` to get `simp` to work.
suffices ((mk l).cons a).bind f hf = ((mk l).bind f hf).append (f a) by exact this
simp only [ListBlank.append_mk, ListBlank.bind_mk, ListBlank.cons_mk, List.cons_bind]
#align turing.list_blank.cons_bind Turing.ListBlank.cons_bind
structure Tape (Γ : Type*) [Inhabited Γ] where
head : Γ
left : ListBlank Γ
right : ListBlank Γ
#align turing.tape Turing.Tape
instance Tape.inhabited {Γ} [Inhabited Γ] : Inhabited (Tape Γ) :=
⟨by constructor <;> apply default⟩
#align turing.tape.inhabited Turing.Tape.inhabited
inductive Dir
| left
| right
deriving DecidableEq, Inhabited
#align turing.dir Turing.Dir
def Tape.left₀ {Γ} [Inhabited Γ] (T : Tape Γ) : ListBlank Γ :=
T.left.cons T.head
#align turing.tape.left₀ Turing.Tape.left₀
def Tape.right₀ {Γ} [Inhabited Γ] (T : Tape Γ) : ListBlank Γ :=
T.right.cons T.head
#align turing.tape.right₀ Turing.Tape.right₀
def Tape.move {Γ} [Inhabited Γ] : Dir → Tape Γ → Tape Γ
| Dir.left, ⟨a, L, R⟩ => ⟨L.head, L.tail, R.cons a⟩
| Dir.right, ⟨a, L, R⟩ => ⟨R.head, L.cons a, R.tail⟩
#align turing.tape.move Turing.Tape.move
@[simp]
theorem Tape.move_left_right {Γ} [Inhabited Γ] (T : Tape Γ) :
(T.move Dir.left).move Dir.right = T := by
cases T; simp [Tape.move]
#align turing.tape.move_left_right Turing.Tape.move_left_right
@[simp]
theorem Tape.move_right_left {Γ} [Inhabited Γ] (T : Tape Γ) :
(T.move Dir.right).move Dir.left = T := by
cases T; simp [Tape.move]
#align turing.tape.move_right_left Turing.Tape.move_right_left
def Tape.mk' {Γ} [Inhabited Γ] (L R : ListBlank Γ) : Tape Γ :=
⟨R.head, L, R.tail⟩
#align turing.tape.mk' Turing.Tape.mk'
@[simp]
theorem Tape.mk'_left {Γ} [Inhabited Γ] (L R : ListBlank Γ) : (Tape.mk' L R).left = L :=
rfl
#align turing.tape.mk'_left Turing.Tape.mk'_left
@[simp]
theorem Tape.mk'_head {Γ} [Inhabited Γ] (L R : ListBlank Γ) : (Tape.mk' L R).head = R.head :=
rfl
#align turing.tape.mk'_head Turing.Tape.mk'_head
@[simp]
theorem Tape.mk'_right {Γ} [Inhabited Γ] (L R : ListBlank Γ) : (Tape.mk' L R).right = R.tail :=
rfl
#align turing.tape.mk'_right Turing.Tape.mk'_right
@[simp]
theorem Tape.mk'_right₀ {Γ} [Inhabited Γ] (L R : ListBlank Γ) : (Tape.mk' L R).right₀ = R :=
ListBlank.cons_head_tail _
#align turing.tape.mk'_right₀ Turing.Tape.mk'_right₀
@[simp]
theorem Tape.mk'_left_right₀ {Γ} [Inhabited Γ] (T : Tape Γ) : Tape.mk' T.left T.right₀ = T := by
cases T
simp only [Tape.right₀, Tape.mk', ListBlank.head_cons, ListBlank.tail_cons, eq_self_iff_true,
and_self_iff]
#align turing.tape.mk'_left_right₀ Turing.Tape.mk'_left_right₀
theorem Tape.exists_mk' {Γ} [Inhabited Γ] (T : Tape Γ) : ∃ L R, T = Tape.mk' L R :=
⟨_, _, (Tape.mk'_left_right₀ _).symm⟩
#align turing.tape.exists_mk' Turing.Tape.exists_mk'
@[simp]
theorem Tape.move_left_mk' {Γ} [Inhabited Γ] (L R : ListBlank Γ) :
(Tape.mk' L R).move Dir.left = Tape.mk' L.tail (R.cons L.head) := by
simp only [Tape.move, Tape.mk', ListBlank.head_cons, eq_self_iff_true, ListBlank.cons_head_tail,
and_self_iff, ListBlank.tail_cons]
#align turing.tape.move_left_mk' Turing.Tape.move_left_mk'
@[simp]
theorem Tape.move_right_mk' {Γ} [Inhabited Γ] (L R : ListBlank Γ) :
(Tape.mk' L R).move Dir.right = Tape.mk' (L.cons R.head) R.tail := by
simp only [Tape.move, Tape.mk', ListBlank.head_cons, eq_self_iff_true, ListBlank.cons_head_tail,
and_self_iff, ListBlank.tail_cons]
#align turing.tape.move_right_mk' Turing.Tape.move_right_mk'
def Tape.mk₂ {Γ} [Inhabited Γ] (L R : List Γ) : Tape Γ :=
Tape.mk' (ListBlank.mk L) (ListBlank.mk R)
#align turing.tape.mk₂ Turing.Tape.mk₂
def Tape.mk₁ {Γ} [Inhabited Γ] (l : List Γ) : Tape Γ :=
Tape.mk₂ [] l
#align turing.tape.mk₁ Turing.Tape.mk₁
def Tape.nth {Γ} [Inhabited Γ] (T : Tape Γ) : ℤ → Γ
| 0 => T.head
| (n + 1 : ℕ) => T.right.nth n
| -(n + 1 : ℕ) => T.left.nth n
#align turing.tape.nth Turing.Tape.nth
@[simp]
theorem Tape.nth_zero {Γ} [Inhabited Γ] (T : Tape Γ) : T.nth 0 = T.1 :=
rfl
#align turing.tape.nth_zero Turing.Tape.nth_zero
theorem Tape.right₀_nth {Γ} [Inhabited Γ] (T : Tape Γ) (n : ℕ) : T.right₀.nth n = T.nth n := by
cases n <;> simp only [Tape.nth, Tape.right₀, Int.ofNat_zero, ListBlank.nth_zero,
ListBlank.nth_succ, ListBlank.head_cons, ListBlank.tail_cons, Nat.zero_eq]
#align turing.tape.right₀_nth Turing.Tape.right₀_nth
@[simp]
theorem Tape.mk'_nth_nat {Γ} [Inhabited Γ] (L R : ListBlank Γ) (n : ℕ) :
(Tape.mk' L R).nth n = R.nth n := by
rw [← Tape.right₀_nth, Tape.mk'_right₀]
#align turing.tape.mk'_nth_nat Turing.Tape.mk'_nth_nat
@[simp]
theorem Tape.move_left_nth {Γ} [Inhabited Γ] :
∀ (T : Tape Γ) (i : ℤ), (T.move Dir.left).nth i = T.nth (i - 1)
| ⟨_, L, _⟩, -(n + 1 : ℕ) => (ListBlank.nth_succ _ _).symm
| ⟨_, L, _⟩, 0 => (ListBlank.nth_zero _).symm
| ⟨a, L, R⟩, 1 => (ListBlank.nth_zero _).trans (ListBlank.head_cons _ _)
| ⟨a, L, R⟩, (n + 1 : ℕ) + 1 => by
rw [add_sub_cancel_right]
change (R.cons a).nth (n + 1) = R.nth n
rw [ListBlank.nth_succ, ListBlank.tail_cons]
#align turing.tape.move_left_nth Turing.Tape.move_left_nth
@[simp]
theorem Tape.move_right_nth {Γ} [Inhabited Γ] (T : Tape Γ) (i : ℤ) :
(T.move Dir.right).nth i = T.nth (i + 1) := by
conv => rhs; rw [← T.move_right_left]
rw [Tape.move_left_nth, add_sub_cancel_right]
#align turing.tape.move_right_nth Turing.Tape.move_right_nth
@[simp]
theorem Tape.move_right_n_head {Γ} [Inhabited Γ] (T : Tape Γ) (i : ℕ) :
((Tape.move Dir.right)^[i] T).head = T.nth i := by
induction i generalizing T
· rfl
· simp only [*, Tape.move_right_nth, Int.ofNat_succ, iterate_succ, Function.comp_apply]
#align turing.tape.move_right_n_head Turing.Tape.move_right_n_head
def Tape.write {Γ} [Inhabited Γ] (b : Γ) (T : Tape Γ) : Tape Γ :=
{ T with head := b }
#align turing.tape.write Turing.Tape.write
@[simp]
theorem Tape.write_self {Γ} [Inhabited Γ] : ∀ T : Tape Γ, T.write T.1 = T := by
rintro ⟨⟩; rfl
#align turing.tape.write_self Turing.Tape.write_self
@[simp]
theorem Tape.write_nth {Γ} [Inhabited Γ] (b : Γ) :
∀ (T : Tape Γ) {i : ℤ}, (T.write b).nth i = if i = 0 then b else T.nth i
| _, 0 => rfl
| _, (_ + 1 : ℕ) => rfl
| _, -(_ + 1 : ℕ) => rfl
#align turing.tape.write_nth Turing.Tape.write_nth
@[simp]
theorem Tape.write_mk' {Γ} [Inhabited Γ] (a b : Γ) (L R : ListBlank Γ) :
(Tape.mk' L (R.cons a)).write b = Tape.mk' L (R.cons b) := by
simp only [Tape.write, Tape.mk', ListBlank.head_cons, ListBlank.tail_cons, eq_self_iff_true,
and_self_iff]
#align turing.tape.write_mk' Turing.Tape.write_mk'
def Tape.map {Γ Γ'} [Inhabited Γ] [Inhabited Γ'] (f : PointedMap Γ Γ') (T : Tape Γ) : Tape Γ' :=
⟨f T.1, T.2.map f, T.3.map f⟩
#align turing.tape.map Turing.Tape.map
@[simp]
theorem Tape.map_fst {Γ Γ'} [Inhabited Γ] [Inhabited Γ'] (f : PointedMap Γ Γ') :
∀ T : Tape Γ, (T.map f).1 = f T.1 := by
rintro ⟨⟩; rfl
#align turing.tape.map_fst Turing.Tape.map_fst
@[simp]
theorem Tape.map_write {Γ Γ'} [Inhabited Γ] [Inhabited Γ'] (f : PointedMap Γ Γ') (b : Γ) :
∀ T : Tape Γ, (T.write b).map f = (T.map f).write (f b) := by
rintro ⟨⟩; rfl
#align turing.tape.map_write Turing.Tape.map_write
-- Porting note: `simpNF` complains about LHS does not simplify when using the simp lemma on
-- itself, but it does indeed.
@[simp, nolint simpNF]
theorem Tape.write_move_right_n {Γ} [Inhabited Γ] (f : Γ → Γ) (L R : ListBlank Γ) (n : ℕ) :
((Tape.move Dir.right)^[n] (Tape.mk' L R)).write (f (R.nth n)) =
(Tape.move Dir.right)^[n] (Tape.mk' L (R.modifyNth f n)) := by
induction' n with n IH generalizing L R
· simp only [ListBlank.nth_zero, ListBlank.modifyNth, iterate_zero_apply, Nat.zero_eq]
rw [← Tape.write_mk', ListBlank.cons_head_tail]
simp only [ListBlank.head_cons, ListBlank.nth_succ, ListBlank.modifyNth, Tape.move_right_mk',
ListBlank.tail_cons, iterate_succ_apply, IH]
#align turing.tape.write_move_right_n Turing.Tape.write_move_right_n
theorem Tape.map_move {Γ Γ'} [Inhabited Γ] [Inhabited Γ'] (f : PointedMap Γ Γ') (T : Tape Γ) (d) :
(T.move d).map f = (T.map f).move d := by
cases T
cases d <;> simp only [Tape.move, Tape.map, ListBlank.head_map, eq_self_iff_true,
ListBlank.map_cons, and_self_iff, ListBlank.tail_map]
#align turing.tape.map_move Turing.Tape.map_move
theorem Tape.map_mk' {Γ Γ'} [Inhabited Γ] [Inhabited Γ'] (f : PointedMap Γ Γ') (L R : ListBlank Γ) :
(Tape.mk' L R).map f = Tape.mk' (L.map f) (R.map f) := by
simp only [Tape.mk', Tape.map, ListBlank.head_map, eq_self_iff_true, and_self_iff,
ListBlank.tail_map]
#align turing.tape.map_mk' Turing.Tape.map_mk'
theorem Tape.map_mk₂ {Γ Γ'} [Inhabited Γ] [Inhabited Γ'] (f : PointedMap Γ Γ') (L R : List Γ) :
(Tape.mk₂ L R).map f = Tape.mk₂ (L.map f) (R.map f) := by
simp only [Tape.mk₂, Tape.map_mk', ListBlank.map_mk]
#align turing.tape.map_mk₂ Turing.Tape.map_mk₂
theorem Tape.map_mk₁ {Γ Γ'} [Inhabited Γ] [Inhabited Γ'] (f : PointedMap Γ Γ') (l : List Γ) :
(Tape.mk₁ l).map f = Tape.mk₁ (l.map f) :=
Tape.map_mk₂ _ _ _
#align turing.tape.map_mk₁ Turing.Tape.map_mk₁
def eval {σ} (f : σ → Option σ) : σ → Part σ :=
PFun.fix fun s ↦ Part.some <| (f s).elim (Sum.inl s) Sum.inr
#align turing.eval Turing.eval
def Reaches {σ} (f : σ → Option σ) : σ → σ → Prop :=
ReflTransGen fun a b ↦ b ∈ f a
#align turing.reaches Turing.Reaches
def Reaches₁ {σ} (f : σ → Option σ) : σ → σ → Prop :=
TransGen fun a b ↦ b ∈ f a
#align turing.reaches₁ Turing.Reaches₁
theorem reaches₁_eq {σ} {f : σ → Option σ} {a b c} (h : f a = f b) :
Reaches₁ f a c ↔ Reaches₁ f b c :=
TransGen.head'_iff.trans (TransGen.head'_iff.trans <| by rw [h]).symm
#align turing.reaches₁_eq Turing.reaches₁_eq
theorem reaches_total {σ} {f : σ → Option σ} {a b c} (hab : Reaches f a b) (hac : Reaches f a c) :
Reaches f b c ∨ Reaches f c b :=
ReflTransGen.total_of_right_unique (fun _ _ _ ↦ Option.mem_unique) hab hac
#align turing.reaches_total Turing.reaches_total
theorem reaches₁_fwd {σ} {f : σ → Option σ} {a b c} (h₁ : Reaches₁ f a c) (h₂ : b ∈ f a) :
Reaches f b c := by
rcases TransGen.head'_iff.1 h₁ with ⟨b', hab, hbc⟩
cases Option.mem_unique hab h₂; exact hbc
#align turing.reaches₁_fwd Turing.reaches₁_fwd
def Reaches₀ {σ} (f : σ → Option σ) (a b : σ) : Prop :=
∀ c, Reaches₁ f b c → Reaches₁ f a c
#align turing.reaches₀ Turing.Reaches₀
theorem Reaches₀.trans {σ} {f : σ → Option σ} {a b c : σ} (h₁ : Reaches₀ f a b)
(h₂ : Reaches₀ f b c) : Reaches₀ f a c
| _, h₃ => h₁ _ (h₂ _ h₃)
#align turing.reaches₀.trans Turing.Reaches₀.trans
@[refl]
theorem Reaches₀.refl {σ} {f : σ → Option σ} (a : σ) : Reaches₀ f a a
| _, h => h
#align turing.reaches₀.refl Turing.Reaches₀.refl
theorem Reaches₀.single {σ} {f : σ → Option σ} {a b : σ} (h : b ∈ f a) : Reaches₀ f a b
| _, h₂ => h₂.head h
#align turing.reaches₀.single Turing.Reaches₀.single
theorem Reaches₀.head {σ} {f : σ → Option σ} {a b c : σ} (h : b ∈ f a) (h₂ : Reaches₀ f b c) :
Reaches₀ f a c :=
(Reaches₀.single h).trans h₂
#align turing.reaches₀.head Turing.Reaches₀.head
theorem Reaches₀.tail {σ} {f : σ → Option σ} {a b c : σ} (h₁ : Reaches₀ f a b) (h : c ∈ f b) :
Reaches₀ f a c :=
h₁.trans (Reaches₀.single h)
#align turing.reaches₀.tail Turing.Reaches₀.tail
theorem reaches₀_eq {σ} {f : σ → Option σ} {a b} (e : f a = f b) : Reaches₀ f a b
| _, h => (reaches₁_eq e).2 h
#align turing.reaches₀_eq Turing.reaches₀_eq
theorem Reaches₁.to₀ {σ} {f : σ → Option σ} {a b : σ} (h : Reaches₁ f a b) : Reaches₀ f a b
| _, h₂ => h.trans h₂
#align turing.reaches₁.to₀ Turing.Reaches₁.to₀
theorem Reaches.to₀ {σ} {f : σ → Option σ} {a b : σ} (h : Reaches f a b) : Reaches₀ f a b
| _, h₂ => h₂.trans_right h
#align turing.reaches.to₀ Turing.Reaches.to₀
theorem Reaches₀.tail' {σ} {f : σ → Option σ} {a b c : σ} (h : Reaches₀ f a b) (h₂ : c ∈ f b) :
Reaches₁ f a c :=
h _ (TransGen.single h₂)
#align turing.reaches₀.tail' Turing.Reaches₀.tail'
@[elab_as_elim]
def evalInduction {σ} {f : σ → Option σ} {b : σ} {C : σ → Sort*} {a : σ}
(h : b ∈ eval f a) (H : ∀ a, b ∈ eval f a → (∀ a', f a = some a' → C a') → C a) : C a :=
PFun.fixInduction h fun a' ha' h' ↦
H _ ha' fun b' e ↦ h' _ <| Part.mem_some_iff.2 <| by rw [e]; rfl
#align turing.eval_induction Turing.evalInduction
theorem mem_eval {σ} {f : σ → Option σ} {a b} : b ∈ eval f a ↔ Reaches f a b ∧ f b = none := by
refine ⟨fun h ↦ ?_, fun ⟨h₁, h₂⟩ ↦ ?_⟩
· -- Porting note: Explicitly specify `c`.
refine @evalInduction _ _ _ (fun a ↦ Reaches f a b ∧ f b = none) _ h fun a h IH ↦ ?_
cases' e : f a with a'
· rw [Part.mem_unique h
(PFun.mem_fix_iff.2 <| Or.inl <| Part.mem_some_iff.2 <| by rw [e] <;> rfl)]
exact ⟨ReflTransGen.refl, e⟩
· rcases PFun.mem_fix_iff.1 h with (h | ⟨_, h, _⟩) <;> rw [e] at h <;>
cases Part.mem_some_iff.1 h
cases' IH a' e with h₁ h₂
exact ⟨ReflTransGen.head e h₁, h₂⟩
· refine ReflTransGen.head_induction_on h₁ ?_ fun h _ IH ↦ ?_
· refine PFun.mem_fix_iff.2 (Or.inl ?_)
rw [h₂]
apply Part.mem_some
· refine PFun.mem_fix_iff.2 (Or.inr ⟨_, ?_, IH⟩)
rw [h]
apply Part.mem_some
#align turing.mem_eval Turing.mem_eval
theorem eval_maximal₁ {σ} {f : σ → Option σ} {a b} (h : b ∈ eval f a) (c) : ¬Reaches₁ f b c
| bc => by
let ⟨_, b0⟩ := mem_eval.1 h
let ⟨b', h', _⟩ := TransGen.head'_iff.1 bc
cases b0.symm.trans h'
#align turing.eval_maximal₁ Turing.eval_maximal₁
theorem eval_maximal {σ} {f : σ → Option σ} {a b} (h : b ∈ eval f a) {c} : Reaches f b c ↔ c = b :=
let ⟨_, b0⟩ := mem_eval.1 h
reflTransGen_iff_eq fun b' h' ↦ by cases b0.symm.trans h'
#align turing.eval_maximal Turing.eval_maximal
theorem reaches_eval {σ} {f : σ → Option σ} {a b} (ab : Reaches f a b) : eval f a = eval f b := by
refine Part.ext fun _ ↦ ⟨fun h ↦ ?_, fun h ↦ ?_⟩
· have ⟨ac, c0⟩ := mem_eval.1 h
exact mem_eval.2 ⟨(or_iff_left_of_imp fun cb ↦ (eval_maximal h).1 cb ▸ ReflTransGen.refl).1
(reaches_total ab ac), c0⟩
· have ⟨bc, c0⟩ := mem_eval.1 h
exact mem_eval.2 ⟨ab.trans bc, c0⟩
#align turing.reaches_eval Turing.reaches_eval
def Respects {σ₁ σ₂} (f₁ : σ₁ → Option σ₁) (f₂ : σ₂ → Option σ₂) (tr : σ₁ → σ₂ → Prop) :=
∀ ⦃a₁ a₂⦄, tr a₁ a₂ → (match f₁ a₁ with
| some b₁ => ∃ b₂, tr b₁ b₂ ∧ Reaches₁ f₂ a₂ b₂
| none => f₂ a₂ = none : Prop)
#align turing.respects Turing.Respects
theorem tr_reaches₁ {σ₁ σ₂ f₁ f₂} {tr : σ₁ → σ₂ → Prop} (H : Respects f₁ f₂ tr) {a₁ a₂}
(aa : tr a₁ a₂) {b₁} (ab : Reaches₁ f₁ a₁ b₁) : ∃ b₂, tr b₁ b₂ ∧ Reaches₁ f₂ a₂ b₂ := by
induction' ab with c₁ ac c₁ d₁ _ cd IH
· have := H aa
rwa [show f₁ a₁ = _ from ac] at this
· rcases IH with ⟨c₂, cc, ac₂⟩
have := H cc
rw [show f₁ c₁ = _ from cd] at this
rcases this with ⟨d₂, dd, cd₂⟩
exact ⟨_, dd, ac₂.trans cd₂⟩
#align turing.tr_reaches₁ Turing.tr_reaches₁
theorem tr_reaches {σ₁ σ₂ f₁ f₂} {tr : σ₁ → σ₂ → Prop} (H : Respects f₁ f₂ tr) {a₁ a₂}
(aa : tr a₁ a₂) {b₁} (ab : Reaches f₁ a₁ b₁) : ∃ b₂, tr b₁ b₂ ∧ Reaches f₂ a₂ b₂ := by
rcases reflTransGen_iff_eq_or_transGen.1 ab with (rfl | ab)
· exact ⟨_, aa, ReflTransGen.refl⟩
· have ⟨b₂, bb, h⟩ := tr_reaches₁ H aa ab
exact ⟨b₂, bb, h.to_reflTransGen⟩
#align turing.tr_reaches Turing.tr_reaches
theorem tr_reaches_rev {σ₁ σ₂ f₁ f₂} {tr : σ₁ → σ₂ → Prop} (H : Respects f₁ f₂ tr) {a₁ a₂}
(aa : tr a₁ a₂) {b₂} (ab : Reaches f₂ a₂ b₂) :
∃ c₁ c₂, Reaches f₂ b₂ c₂ ∧ tr c₁ c₂ ∧ Reaches f₁ a₁ c₁ := by
induction' ab with c₂ d₂ _ cd IH
· exact ⟨_, _, ReflTransGen.refl, aa, ReflTransGen.refl⟩
· rcases IH with ⟨e₁, e₂, ce, ee, ae⟩
rcases ReflTransGen.cases_head ce with (rfl | ⟨d', cd', de⟩)
· have := H ee
revert this
cases' eg : f₁ e₁ with g₁ <;> simp only [Respects, and_imp, exists_imp]
· intro c0
cases cd.symm.trans c0
· intro g₂ gg cg
rcases TransGen.head'_iff.1 cg with ⟨d', cd', dg⟩
cases Option.mem_unique cd cd'
exact ⟨_, _, dg, gg, ae.tail eg⟩
· cases Option.mem_unique cd cd'
exact ⟨_, _, de, ee, ae⟩
#align turing.tr_reaches_rev Turing.tr_reaches_rev
theorem tr_eval {σ₁ σ₂ f₁ f₂} {tr : σ₁ → σ₂ → Prop} (H : Respects f₁ f₂ tr) {a₁ b₁ a₂}
(aa : tr a₁ a₂) (ab : b₁ ∈ eval f₁ a₁) : ∃ b₂, tr b₁ b₂ ∧ b₂ ∈ eval f₂ a₂ := by
cases' mem_eval.1 ab with ab b0
rcases tr_reaches H aa ab with ⟨b₂, bb, ab⟩
refine ⟨_, bb, mem_eval.2 ⟨ab, ?_⟩⟩
have := H bb; rwa [b0] at this
#align turing.tr_eval Turing.tr_eval
| Mathlib/Computability/TuringMachine.lean | 937 | 949 | theorem tr_eval_rev {σ₁ σ₂ f₁ f₂} {tr : σ₁ → σ₂ → Prop} (H : Respects f₁ f₂ tr) {a₁ b₂ a₂}
(aa : tr a₁ a₂) (ab : b₂ ∈ eval f₂ a₂) : ∃ b₁, tr b₁ b₂ ∧ b₁ ∈ eval f₁ a₁ := by |
cases' mem_eval.1 ab with ab b0
rcases tr_reaches_rev H aa ab with ⟨c₁, c₂, bc, cc, ac⟩
cases (reflTransGen_iff_eq (Option.eq_none_iff_forall_not_mem.1 b0)).1 bc
refine ⟨_, cc, mem_eval.2 ⟨ac, ?_⟩⟩
have := H cc
cases' hfc : f₁ c₁ with d₁
· rfl
rw [hfc] at this
rcases this with ⟨d₂, _, bd⟩
rcases TransGen.head'_iff.1 bd with ⟨e, h, _⟩
cases b0.symm.trans h
|
import Mathlib.Analysis.SpecialFunctions.Gaussian.FourierTransform
import Mathlib.Analysis.Fourier.PoissonSummation
open Real Set MeasureTheory Filter Asymptotics intervalIntegral
open scoped Real Topology FourierTransform RealInnerProductSpace
open Complex hiding exp continuous_exp abs_of_nonneg sq_abs
noncomputable section
section GaussianPoisson
variable {E : Type*} [NormedAddCommGroup E]
lemma rexp_neg_quadratic_isLittleO_rpow_atTop {a : ℝ} (ha : a < 0) (b s : ℝ) :
(fun x ↦ rexp (a * x ^ 2 + b * x)) =o[atTop] (· ^ s) := by
suffices (fun x ↦ rexp (a * x ^ 2 + b * x)) =o[atTop] (fun x ↦ rexp (-x)) by
refine this.trans ?_
simpa only [neg_one_mul] using isLittleO_exp_neg_mul_rpow_atTop zero_lt_one s
rw [isLittleO_exp_comp_exp_comp]
have : (fun x ↦ -x - (a * x ^ 2 + b * x)) = fun x ↦ x * (-a * x - (b + 1)) := by
ext1 x; ring_nf
rw [this]
exact tendsto_id.atTop_mul_atTop <|
Filter.tendsto_atTop_add_const_right _ _ <| tendsto_id.const_mul_atTop (neg_pos.mpr ha)
lemma cexp_neg_quadratic_isLittleO_rpow_atTop {a : ℂ} (ha : a.re < 0) (b : ℂ) (s : ℝ) :
(fun x : ℝ ↦ cexp (a * x ^ 2 + b * x)) =o[atTop] (· ^ s) := by
apply Asymptotics.IsLittleO.of_norm_left
convert rexp_neg_quadratic_isLittleO_rpow_atTop ha b.re s with x
simp_rw [Complex.norm_eq_abs, Complex.abs_exp, add_re, ← ofReal_pow, mul_comm (_ : ℂ) ↑(_ : ℝ),
re_ofReal_mul, mul_comm _ (re _)]
lemma cexp_neg_quadratic_isLittleO_abs_rpow_cocompact {a : ℂ} (ha : a.re < 0) (b : ℂ) (s : ℝ) :
(fun x : ℝ ↦ cexp (a * x ^ 2 + b * x)) =o[cocompact ℝ] (|·| ^ s) := by
rw [cocompact_eq_atBot_atTop, isLittleO_sup]
constructor
· refine ((cexp_neg_quadratic_isLittleO_rpow_atTop ha (-b) s).comp_tendsto
Filter.tendsto_neg_atBot_atTop).congr' (eventually_of_forall fun x ↦ ?_) ?_
· simp only [neg_mul, Function.comp_apply, ofReal_neg, neg_sq, mul_neg, neg_neg]
· refine (eventually_lt_atBot 0).mp (eventually_of_forall fun x hx ↦ ?_)
simp only [Function.comp_apply, abs_of_neg hx]
· refine (cexp_neg_quadratic_isLittleO_rpow_atTop ha b s).congr' EventuallyEq.rfl ?_
refine (eventually_gt_atTop 0).mp (eventually_of_forall fun x hx ↦ ?_)
simp_rw [abs_of_pos hx]
theorem tendsto_rpow_abs_mul_exp_neg_mul_sq_cocompact {a : ℝ} (ha : 0 < a) (s : ℝ) :
Tendsto (fun x : ℝ => |x| ^ s * rexp (-a * x ^ 2)) (cocompact ℝ) (𝓝 0) := by
conv in rexp _ => rw [← sq_abs]
erw [cocompact_eq_atBot_atTop, ← comap_abs_atTop,
@tendsto_comap'_iff _ _ _ (fun y => y ^ s * rexp (-a * y ^ 2)) _ _ _
(mem_atTop_sets.mpr ⟨0, fun b hb => ⟨b, abs_of_nonneg hb⟩⟩)]
exact
(rpow_mul_exp_neg_mul_sq_isLittleO_exp_neg ha s).tendsto_zero_of_tendsto
(tendsto_exp_atBot.comp <| tendsto_id.const_mul_atTop_of_neg (neg_lt_zero.mpr one_half_pos))
#align tendsto_rpow_abs_mul_exp_neg_mul_sq_cocompact tendsto_rpow_abs_mul_exp_neg_mul_sq_cocompact
theorem isLittleO_exp_neg_mul_sq_cocompact {a : ℂ} (ha : 0 < a.re) (s : ℝ) :
(fun x : ℝ => Complex.exp (-a * x ^ 2)) =o[cocompact ℝ] fun x : ℝ => |x| ^ s := by
convert cexp_neg_quadratic_isLittleO_abs_rpow_cocompact (?_ : (-a).re < 0) 0 s using 1
· simp_rw [zero_mul, add_zero]
· rwa [neg_re, neg_lt_zero]
#align is_o_exp_neg_mul_sq_cocompact isLittleO_exp_neg_mul_sq_cocompact
| Mathlib/Analysis/SpecialFunctions/Gaussian/PoissonSummation.lean | 88 | 122 | theorem Complex.tsum_exp_neg_quadratic {a : ℂ} (ha : 0 < a.re) (b : ℂ) :
(∑' n : ℤ, cexp (-π * a * n ^ 2 + 2 * π * b * n)) =
1 / a ^ (1 / 2 : ℂ) * ∑' n : ℤ, cexp (-π / a * (n + I * b) ^ 2) := by |
let f : ℝ → ℂ := fun x ↦ cexp (-π * a * x ^ 2 + 2 * π * b * x)
have hCf : Continuous f := by
refine Complex.continuous_exp.comp (Continuous.add ?_ ?_)
· exact continuous_const.mul (Complex.continuous_ofReal.pow 2)
· exact continuous_const.mul Complex.continuous_ofReal
have hFf : 𝓕 f = fun x : ℝ ↦ 1 / a ^ (1 / 2 : ℂ) * cexp (-π / a * (x + I * b) ^ 2) :=
fourierIntegral_gaussian_pi' ha b
have h1 : 0 < (↑π * a).re := by
rw [re_ofReal_mul]
exact mul_pos pi_pos ha
have h2 : 0 < (↑π / a).re := by
rw [div_eq_mul_inv, re_ofReal_mul, inv_re]
refine mul_pos pi_pos (div_pos ha <| normSq_pos.mpr ?_)
contrapose! ha
rw [ha, zero_re]
have f_bd : f =O[cocompact ℝ] (fun x => |x| ^ (-2 : ℝ)) := by
convert (cexp_neg_quadratic_isLittleO_abs_rpow_cocompact ?_ _ (-2)).isBigO
rwa [neg_mul, neg_re, neg_lt_zero]
have Ff_bd : (𝓕 f) =O[cocompact ℝ] (fun x => |x| ^ (-2 : ℝ)) := by
rw [hFf]
have : ∀ (x : ℝ), -↑π / a * (↑x + I * b) ^ 2 =
-↑π / a * x ^ 2 + (-2 * π * I * b) / a * x + π * b ^ 2 / a := by
intro x; ring_nf; rw [I_sq]; ring
simp_rw [this]
conv => enter [2, x]; rw [Complex.exp_add, ← mul_assoc _ _ (Complex.exp _), mul_comm]
refine ((cexp_neg_quadratic_isLittleO_abs_rpow_cocompact
(?_) (-2 * ↑π * I * b / a) (-2)).isBigO.const_mul_left _).const_mul_left _
rwa [neg_div, neg_re, neg_lt_zero]
convert Real.tsum_eq_tsum_fourierIntegral_of_rpow_decay hCf one_lt_two f_bd Ff_bd 0 using 1
· simp only [f, zero_add, ofReal_intCast]
· rw [← tsum_mul_left]
simp only [QuotientAddGroup.mk_zero, fourier_eval_zero, mul_one, hFf, ofReal_intCast]
|
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⟧}
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]
#align power_series.exists_coeff_ne_zero_iff_ne_zero PowerSeries.exists_coeff_ne_zero_iff_ne_zero
def order (φ : R⟦X⟧) : PartENat :=
letI := Classical.decEq R
letI := Classical.decEq R⟦X⟧
if h : φ = 0 then ⊤ else Nat.find (exists_coeff_ne_zero_iff_ne_zero.mpr h)
#align power_series.order PowerSeries.order
@[simp]
theorem order_zero : order (0 : R⟦X⟧) = ⊤ :=
dif_pos rfl
#align power_series.order_zero PowerSeries.order_zero
theorem order_finite_iff_ne_zero : (order φ).Dom ↔ φ ≠ 0 := by
simp only [order]
constructor
· split_ifs with h <;> intro H
· simp only [PartENat.top_eq_none, Part.not_none_dom] at H
· exact h
· intro h
simp [h]
#align power_series.order_finite_iff_ne_zero PowerSeries.order_finite_iff_ne_zero
theorem coeff_order (h : (order φ).Dom) : coeff R (φ.order.get h) φ ≠ 0 := by
classical
simp only [order, order_finite_iff_ne_zero.mp h, not_false_iff, dif_neg, PartENat.get_natCast']
generalize_proofs h
exact Nat.find_spec h
#align power_series.coeff_order PowerSeries.coeff_order
theorem order_le (n : ℕ) (h : coeff R n φ ≠ 0) : order φ ≤ n := by
classical
rw [order, dif_neg]
· simp only [PartENat.coe_le_coe]
exact Nat.find_le h
· exact exists_coeff_ne_zero_iff_ne_zero.mp ⟨n, h⟩
#align power_series.order_le PowerSeries.order_le
theorem coeff_of_lt_order (n : ℕ) (h : ↑n < order φ) : coeff R n φ = 0 := by
contrapose! h
exact order_le _ h
#align power_series.coeff_of_lt_order PowerSeries.coeff_of_lt_order
@[simp]
theorem order_eq_top {φ : R⟦X⟧} : φ.order = ⊤ ↔ φ = 0 :=
PartENat.not_dom_iff_eq_top.symm.trans order_finite_iff_ne_zero.not_left
#align power_series.order_eq_top PowerSeries.order_eq_top
theorem nat_le_order (φ : R⟦X⟧) (n : ℕ) (h : ∀ i < n, coeff R i φ = 0) : ↑n ≤ order φ := by
by_contra H; rw [not_le] at H
have : (order φ).Dom := PartENat.dom_of_le_natCast H.le
rw [← PartENat.natCast_get this, PartENat.coe_lt_coe] at H
exact coeff_order this (h _ H)
#align power_series.nat_le_order PowerSeries.nat_le_order
theorem le_order (φ : R⟦X⟧) (n : PartENat) (h : ∀ i : ℕ, ↑i < n → coeff R i φ = 0) :
n ≤ order φ := by
induction n using PartENat.casesOn
· show _ ≤ _
rw [top_le_iff, order_eq_top]
ext i
exact h _ (PartENat.natCast_lt_top i)
· apply nat_le_order
simpa only [PartENat.coe_lt_coe] using h
#align power_series.le_order PowerSeries.le_order
theorem order_eq_nat {φ : R⟦X⟧} {n : ℕ} :
order φ = n ↔ coeff R n φ ≠ 0 ∧ ∀ i, i < n → coeff R i φ = 0 := by
classical
rcases eq_or_ne φ 0 with (rfl | hφ)
· simpa [(coeff R _).map_zero] using (PartENat.natCast_ne_top _).symm
simp [order, dif_neg hφ, Nat.find_eq_iff]
#align power_series.order_eq_nat PowerSeries.order_eq_nat
theorem order_eq {φ : R⟦X⟧} {n : PartENat} :
order φ = n ↔ (∀ i : ℕ, ↑i = n → coeff R i φ ≠ 0) ∧ ∀ i : ℕ, ↑i < n → coeff R i φ = 0 := by
induction n using PartENat.casesOn
· rw [order_eq_top]
constructor
· rintro rfl
constructor <;> intros
· exfalso
exact PartENat.natCast_ne_top ‹_› ‹_›
· exact (coeff _ _).map_zero
· rintro ⟨_h₁, h₂⟩
ext i
exact h₂ i (PartENat.natCast_lt_top i)
· simpa [PartENat.natCast_inj] using order_eq_nat
#align power_series.order_eq PowerSeries.order_eq
theorem le_order_add (φ ψ : R⟦X⟧) : min (order φ) (order ψ) ≤ order (φ + ψ) := by
refine le_order _ _ ?_
simp (config := { contextual := true }) [coeff_of_lt_order]
#align power_series.le_order_add PowerSeries.le_order_add
private theorem order_add_of_order_eq.aux (φ ψ : R⟦X⟧) (_h : order φ ≠ order ψ)
(H : order φ < order ψ) : order (φ + ψ) ≤ order φ ⊓ order ψ := by
suffices order (φ + ψ) = order φ by
rw [le_inf_iff, this]
exact ⟨le_rfl, le_of_lt H⟩
rw [order_eq]
constructor
· intro i hi
rw [← hi] at H
rw [(coeff _ _).map_add, coeff_of_lt_order i H, add_zero]
exact (order_eq_nat.1 hi.symm).1
· intro i hi
rw [(coeff _ _).map_add, coeff_of_lt_order i hi, coeff_of_lt_order i (lt_trans hi H),
zero_add]
-- #align power_series.order_add_of_order_eq.aux power_series.order_add_of_order_eq.aux
theorem order_add_of_order_eq (φ ψ : R⟦X⟧) (h : order φ ≠ order ψ) :
order (φ + ψ) = order φ ⊓ order ψ := by
refine le_antisymm ?_ (le_order_add _ _)
by_cases H₁ : order φ < order ψ
· apply order_add_of_order_eq.aux _ _ h H₁
by_cases H₂ : order ψ < order φ
· simpa only [add_comm, inf_comm] using order_add_of_order_eq.aux _ _ h.symm H₂
exfalso; exact h (le_antisymm (not_lt.1 H₂) (not_lt.1 H₁))
#align power_series.order_add_of_order_eq PowerSeries.order_add_of_order_eq
theorem order_mul_ge (φ ψ : R⟦X⟧) : order φ + order ψ ≤ order (φ * ψ) := by
apply le_order
intro n hn; rw [coeff_mul, Finset.sum_eq_zero]
rintro ⟨i, j⟩ hij
by_cases hi : ↑i < order φ
· rw [coeff_of_lt_order i hi, zero_mul]
by_cases hj : ↑j < order ψ
· rw [coeff_of_lt_order j hj, mul_zero]
rw [not_lt] at hi hj; rw [mem_antidiagonal] at hij
exfalso
apply ne_of_lt (lt_of_lt_of_le hn <| add_le_add hi hj)
rw [← Nat.cast_add, hij]
#align power_series.order_mul_ge PowerSeries.order_mul_ge
| Mathlib/RingTheory/PowerSeries/Order.lean | 212 | 222 | theorem order_monomial (n : ℕ) (a : R) [Decidable (a = 0)] :
order (monomial R n a) = if a = 0 then (⊤ : PartENat) else n := by |
split_ifs with h
· rw [h, order_eq_top, LinearMap.map_zero]
· rw [order_eq]
constructor <;> intro i hi
· rw [PartENat.natCast_inj] at hi
rwa [hi, coeff_monomial_same]
· rw [PartENat.coe_lt_coe] at hi
rw [coeff_monomial, if_neg]
exact ne_of_lt hi
|
import Mathlib.CategoryTheory.Comma.Arrow
import Mathlib.CategoryTheory.Pi.Basic
import Mathlib.Order.CompleteBooleanAlgebra
#align_import category_theory.morphism_property from "leanprover-community/mathlib"@"7f963633766aaa3ebc8253100a5229dd463040c7"
universe w v v' u u'
open CategoryTheory Opposite
noncomputable section
namespace CategoryTheory
variable (C : Type u) [Category.{v} C] {D : Type*} [Category D]
def MorphismProperty :=
∀ ⦃X Y : C⦄ (_ : X ⟶ Y), Prop
#align category_theory.morphism_property CategoryTheory.MorphismProperty
instance : CompleteBooleanAlgebra (MorphismProperty C) where
le P₁ P₂ := ∀ ⦃X Y : C⦄ (f : X ⟶ Y), P₁ f → P₂ f
__ := inferInstanceAs (CompleteBooleanAlgebra (∀ ⦃X Y : C⦄ (_ : X ⟶ Y), Prop))
lemma MorphismProperty.le_def {P Q : MorphismProperty C} :
P ≤ Q ↔ ∀ {X Y : C} (f : X ⟶ Y), P f → Q f := Iff.rfl
instance : Inhabited (MorphismProperty C) :=
⟨⊤⟩
lemma MorphismProperty.top_eq : (⊤ : MorphismProperty C) = fun _ _ _ => True := rfl
variable {C}
namespace MorphismProperty
@[ext]
lemma ext (W W' : MorphismProperty C) (h : ∀ ⦃X Y : C⦄ (f : X ⟶ Y), W f ↔ W' f) :
W = W' := by
funext X Y f
rw [h]
@[simp]
lemma top_apply {X Y : C} (f : X ⟶ Y) : (⊤ : MorphismProperty C) f := by
simp only [top_eq]
@[simp]
def op (P : MorphismProperty C) : MorphismProperty Cᵒᵖ := fun _ _ f => P f.unop
#align category_theory.morphism_property.op CategoryTheory.MorphismProperty.op
@[simp]
def unop (P : MorphismProperty Cᵒᵖ) : MorphismProperty C := fun _ _ f => P f.op
#align category_theory.morphism_property.unop CategoryTheory.MorphismProperty.unop
theorem unop_op (P : MorphismProperty C) : P.op.unop = P :=
rfl
#align category_theory.morphism_property.unop_op CategoryTheory.MorphismProperty.unop_op
theorem op_unop (P : MorphismProperty Cᵒᵖ) : P.unop.op = P :=
rfl
#align category_theory.morphism_property.op_unop CategoryTheory.MorphismProperty.op_unop
def inverseImage (P : MorphismProperty D) (F : C ⥤ D) : MorphismProperty C := fun _ _ f =>
P (F.map f)
#align category_theory.morphism_property.inverse_image CategoryTheory.MorphismProperty.inverseImage
@[simp]
lemma inverseImage_iff (P : MorphismProperty D) (F : C ⥤ D) {X Y : C} (f : X ⟶ Y) :
P.inverseImage F f ↔ P (F.map f) := by rfl
def map (P : MorphismProperty C) (F : C ⥤ D) : MorphismProperty D := fun _ _ f =>
∃ (X' Y' : C) (f' : X' ⟶ Y') (_ : P f'), Nonempty (Arrow.mk (F.map f') ≅ Arrow.mk f)
lemma map_mem_map (P : MorphismProperty C) (F : C ⥤ D) {X Y : C} (f : X ⟶ Y) (hf : P f) :
(P.map F) (F.map f) := ⟨X, Y, f, hf, ⟨Iso.refl _⟩⟩
lemma monotone_map (F : C ⥤ D) :
Monotone (map · F) := by
intro P Q h X Y f ⟨X', Y', f', hf', ⟨e⟩⟩
exact ⟨X', Y', f', h _ hf', ⟨e⟩⟩
def RespectsIso (P : MorphismProperty C) : Prop :=
(∀ {X Y Z} (e : X ≅ Y) (f : Y ⟶ Z), P f → P (e.hom ≫ f)) ∧
∀ {X Y Z} (e : Y ≅ Z) (f : X ⟶ Y), P f → P (f ≫ e.hom)
#align category_theory.morphism_property.respects_iso CategoryTheory.MorphismProperty.RespectsIso
theorem RespectsIso.op {P : MorphismProperty C} (h : RespectsIso P) : RespectsIso P.op :=
⟨fun e f hf => h.2 e.unop f.unop hf, fun e f hf => h.1 e.unop f.unop hf⟩
#align category_theory.morphism_property.respects_iso.op CategoryTheory.MorphismProperty.RespectsIso.op
theorem RespectsIso.unop {P : MorphismProperty Cᵒᵖ} (h : RespectsIso P) : RespectsIso P.unop :=
⟨fun e f hf => h.2 e.op f.op hf, fun e f hf => h.1 e.op f.op hf⟩
#align category_theory.morphism_property.respects_iso.unop CategoryTheory.MorphismProperty.RespectsIso.unop
def isoClosure (P : MorphismProperty C) : MorphismProperty C :=
fun _ _ f => ∃ (Y₁ Y₂ : C) (f' : Y₁ ⟶ Y₂) (_ : P f'), Nonempty (Arrow.mk f' ≅ Arrow.mk f)
lemma le_isoClosure (P : MorphismProperty C) : P ≤ P.isoClosure :=
fun _ _ f hf => ⟨_, _, f, hf, ⟨Iso.refl _⟩⟩
lemma isoClosure_respectsIso (P : MorphismProperty C) :
RespectsIso P.isoClosure :=
⟨fun e f ⟨_, _, f', hf', ⟨iso⟩⟩ =>
⟨_, _, f', hf', ⟨Arrow.isoMk (asIso iso.hom.left ≪≫ e.symm)
(asIso iso.hom.right) (by simp)⟩⟩,
fun e f ⟨_, _, f', hf', ⟨iso⟩⟩ =>
⟨_, _, f', hf', ⟨Arrow.isoMk (asIso iso.hom.left)
(asIso iso.hom.right ≪≫ e) (by simp)⟩⟩⟩
lemma monotone_isoClosure : Monotone (isoClosure (C := C)) := by
intro P Q h X Y f ⟨X', Y', f', hf', ⟨e⟩⟩
exact ⟨X', Y', f', h _ hf', ⟨e⟩⟩
theorem RespectsIso.cancel_left_isIso {P : MorphismProperty C} (hP : RespectsIso P) {X Y Z : C}
(f : X ⟶ Y) (g : Y ⟶ Z) [IsIso f] : P (f ≫ g) ↔ P g :=
⟨fun h => by simpa using hP.1 (asIso f).symm (f ≫ g) h, hP.1 (asIso f) g⟩
#align category_theory.morphism_property.respects_iso.cancel_left_is_iso CategoryTheory.MorphismProperty.RespectsIso.cancel_left_isIso
theorem RespectsIso.cancel_right_isIso {P : MorphismProperty C} (hP : RespectsIso P) {X Y Z : C}
(f : X ⟶ Y) (g : Y ⟶ Z) [IsIso g] : P (f ≫ g) ↔ P f :=
⟨fun h => by simpa using hP.2 (asIso g).symm (f ≫ g) h, hP.2 (asIso g) f⟩
#align category_theory.morphism_property.respects_iso.cancel_right_is_iso CategoryTheory.MorphismProperty.RespectsIso.cancel_right_isIso
theorem RespectsIso.arrow_iso_iff {P : MorphismProperty C} (hP : RespectsIso P) {f g : Arrow C}
(e : f ≅ g) : P f.hom ↔ P g.hom := by
rw [← Arrow.inv_left_hom_right e.hom, hP.cancel_left_isIso, hP.cancel_right_isIso]
#align category_theory.morphism_property.respects_iso.arrow_iso_iff CategoryTheory.MorphismProperty.RespectsIso.arrow_iso_iff
theorem RespectsIso.arrow_mk_iso_iff {P : MorphismProperty C} (hP : RespectsIso P) {W X Y Z : C}
{f : W ⟶ X} {g : Y ⟶ Z} (e : Arrow.mk f ≅ Arrow.mk g) : P f ↔ P g :=
hP.arrow_iso_iff e
#align category_theory.morphism_property.respects_iso.arrow_mk_iso_iff CategoryTheory.MorphismProperty.RespectsIso.arrow_mk_iso_iff
| Mathlib/CategoryTheory/MorphismProperty/Basic.lean | 158 | 168 | theorem RespectsIso.of_respects_arrow_iso (P : MorphismProperty C)
(hP : ∀ (f g : Arrow C) (_ : f ≅ g) (_ : P f.hom), P g.hom) : RespectsIso P := by |
constructor
· intro X Y Z e f hf
refine hP (Arrow.mk f) (Arrow.mk (e.hom ≫ f)) (Arrow.isoMk e.symm (Iso.refl _) ?_) hf
dsimp
simp only [Iso.inv_hom_id_assoc, Category.comp_id]
· intro X Y Z e f hf
refine hP (Arrow.mk f) (Arrow.mk (f ≫ e.hom)) (Arrow.isoMk (Iso.refl _) e ?_) hf
dsimp
simp only [Category.id_comp]
|
import Mathlib.Data.Complex.Exponential
import Mathlib.Analysis.SpecialFunctions.Log.Deriv
#align_import data.complex.exponential_bounds from "leanprover-community/mathlib"@"402f8982dddc1864bd703da2d6e2ee304a866973"
namespace Real
open IsAbsoluteValue Finset CauSeq Complex
| Mathlib/Data/Complex/ExponentialBounds.lean | 20 | 25 | theorem exp_one_near_10 : |exp 1 - 2244083 / 825552| ≤ 1 / 10 ^ 10 := by |
apply exp_approx_start
iterate 13 refine exp_1_approx_succ_eq (by norm_num1; rfl) (by norm_cast) ?_
norm_num1
refine exp_approx_end' _ (by norm_num1; rfl) _ (by norm_cast) (by simp) ?_
rw [_root_.abs_one, abs_of_pos] <;> norm_num1
|
import Mathlib.Algebra.GeomSum
import Mathlib.Algebra.Polynomial.Roots
import Mathlib.GroupTheory.SpecificGroups.Cyclic
#align_import ring_theory.integral_domain from "leanprover-community/mathlib"@"6e70e0d419bf686784937d64ed4bfde866ff229e"
section
open Finset Polynomial Function Nat
section CancelMonoidWithZero
-- There doesn't seem to be a better home for these right now
variable {M : Type*} [CancelMonoidWithZero M] [Finite M]
theorem mul_right_bijective_of_finite₀ {a : M} (ha : a ≠ 0) : Bijective fun b => a * b :=
Finite.injective_iff_bijective.1 <| mul_right_injective₀ ha
#align mul_right_bijective_of_finite₀ mul_right_bijective_of_finite₀
theorem mul_left_bijective_of_finite₀ {a : M} (ha : a ≠ 0) : Bijective fun b => b * a :=
Finite.injective_iff_bijective.1 <| mul_left_injective₀ ha
#align mul_left_bijective_of_finite₀ mul_left_bijective_of_finite₀
def Fintype.groupWithZeroOfCancel (M : Type*) [CancelMonoidWithZero M] [DecidableEq M] [Fintype M]
[Nontrivial M] : GroupWithZero M :=
{ ‹Nontrivial M›,
‹CancelMonoidWithZero M› with
inv := fun a => if h : a = 0 then 0 else Fintype.bijInv (mul_right_bijective_of_finite₀ h) 1
mul_inv_cancel := fun a ha => by
simp only [Inv.inv, dif_neg ha]
exact Fintype.rightInverse_bijInv _ _
inv_zero := by simp [Inv.inv, dif_pos rfl] }
#align fintype.group_with_zero_of_cancel Fintype.groupWithZeroOfCancel
| Mathlib/RingTheory/IntegralDomain.lean | 61 | 69 | theorem exists_eq_pow_of_mul_eq_pow_of_coprime {R : Type*} [CommSemiring R] [IsDomain R]
[GCDMonoid R] [Unique Rˣ] {a b c : R} {n : ℕ} (cp : IsCoprime a b) (h : a * b = c ^ n) :
∃ d : R, a = d ^ n := by |
refine exists_eq_pow_of_mul_eq_pow (isUnit_of_dvd_one ?_) h
obtain ⟨x, y, hxy⟩ := cp
rw [← hxy]
exact -- Porting note: added `GCDMonoid.` twice
dvd_add (dvd_mul_of_dvd_right (GCDMonoid.gcd_dvd_left _ _) _)
(dvd_mul_of_dvd_right (GCDMonoid.gcd_dvd_right _ _) _)
|
import Mathlib.Algebra.BigOperators.Ring.List
import Mathlib.Data.Nat.Prime
import Mathlib.Data.List.Prime
import Mathlib.Data.List.Sort
import Mathlib.Data.List.Chain
#align_import data.nat.factors from "leanprover-community/mathlib"@"008205aa645b3f194c1da47025c5f110c8406eab"
open Bool Subtype
open Nat
namespace Nat
attribute [instance 0] instBEqNat
def factors : ℕ → List ℕ
| 0 => []
| 1 => []
| k + 2 =>
let m := minFac (k + 2)
m :: factors ((k + 2) / m)
decreasing_by show (k + 2) / m < (k + 2); exact factors_lemma
#align nat.factors Nat.factors
@[simp]
theorem factors_zero : factors 0 = [] := by rw [factors]
#align nat.factors_zero Nat.factors_zero
@[simp]
theorem factors_one : factors 1 = [] := by rw [factors]
#align nat.factors_one Nat.factors_one
@[simp]
theorem factors_two : factors 2 = [2] := by simp [factors]
theorem prime_of_mem_factors {n : ℕ} : ∀ {p : ℕ}, (h : p ∈ factors n) → Prime p := by
match n with
| 0 => simp
| 1 => simp
| k + 2 =>
intro p h
let m := minFac (k + 2)
have : (k + 2) / m < (k + 2) := factors_lemma
have h₁ : p = m ∨ p ∈ factors ((k + 2) / m) :=
List.mem_cons.1 (by rwa [factors] at h)
exact Or.casesOn h₁ (fun h₂ => h₂.symm ▸ minFac_prime (by simp)) prime_of_mem_factors
#align nat.prime_of_mem_factors Nat.prime_of_mem_factors
theorem pos_of_mem_factors {n p : ℕ} (h : p ∈ factors n) : 0 < p :=
Prime.pos (prime_of_mem_factors h)
#align nat.pos_of_mem_factors Nat.pos_of_mem_factors
theorem prod_factors : ∀ {n}, n ≠ 0 → List.prod (factors n) = n
| 0 => by simp
| 1 => by simp
| k + 2 => fun _ =>
let m := minFac (k + 2)
have : (k + 2) / m < (k + 2) := factors_lemma
show (factors (k + 2)).prod = (k + 2) by
have h₁ : (k + 2) / m ≠ 0 := fun h => by
have : (k + 2) = 0 * m := (Nat.div_eq_iff_eq_mul_left (minFac_pos _) (minFac_dvd _)).1 h
rw [zero_mul] at this; exact (show k + 2 ≠ 0 by simp) this
rw [factors, List.prod_cons, prod_factors h₁, Nat.mul_div_cancel' (minFac_dvd _)]
#align nat.prod_factors Nat.prod_factors
theorem factors_prime {p : ℕ} (hp : Nat.Prime p) : p.factors = [p] := by
have : p = p - 2 + 2 := (tsub_eq_iff_eq_add_of_le hp.two_le).mp rfl
rw [this, Nat.factors]
simp only [Eq.symm this]
have : Nat.minFac p = p := (Nat.prime_def_minFac.mp hp).2
simp only [this, Nat.factors, Nat.div_self (Nat.Prime.pos hp)]
#align nat.factors_prime Nat.factors_prime
theorem factors_chain {n : ℕ} :
∀ {a}, (∀ p, Prime p → p ∣ n → a ≤ p) → List.Chain (· ≤ ·) a (factors n) := by
match n with
| 0 => simp
| 1 => simp
| k + 2 =>
intro a h
let m := minFac (k + 2)
have : (k + 2) / m < (k + 2) := factors_lemma
rw [factors]
refine List.Chain.cons ((le_minFac.2 h).resolve_left (by simp)) (factors_chain ?_)
exact fun p pp d => minFac_le_of_dvd pp.two_le (d.trans <| div_dvd_of_dvd <| minFac_dvd _)
#align nat.factors_chain Nat.factors_chain
theorem factors_chain_2 (n) : List.Chain (· ≤ ·) 2 (factors n) :=
factors_chain fun _ pp _ => pp.two_le
#align nat.factors_chain_2 Nat.factors_chain_2
theorem factors_chain' (n) : List.Chain' (· ≤ ·) (factors n) :=
@List.Chain'.tail _ _ (_ :: _) (factors_chain_2 _)
#align nat.factors_chain' Nat.factors_chain'
theorem factors_sorted (n : ℕ) : List.Sorted (· ≤ ·) (factors n) :=
List.chain'_iff_pairwise.1 (factors_chain' _)
#align nat.factors_sorted Nat.factors_sorted
theorem factors_add_two (n : ℕ) :
factors (n + 2) = minFac (n + 2) :: factors ((n + 2) / minFac (n + 2)) := by rw [factors]
#align nat.factors_add_two Nat.factors_add_two
@[simp]
theorem factors_eq_nil (n : ℕ) : n.factors = [] ↔ n = 0 ∨ n = 1 := by
constructor <;> intro h
· rcases n with (_ | _ | n)
· exact Or.inl rfl
· exact Or.inr rfl
· rw [factors] at h
injection h
· rcases h with (rfl | rfl)
· exact factors_zero
· exact factors_one
#align nat.factors_eq_nil Nat.factors_eq_nil
open scoped List in
theorem eq_of_perm_factors {a b : ℕ} (ha : a ≠ 0) (hb : b ≠ 0) (h : a.factors ~ b.factors) :
a = b := by simpa [prod_factors ha, prod_factors hb] using List.Perm.prod_eq h
#align nat.eq_of_perm_factors Nat.eq_of_perm_factors
section
open List
theorem mem_factors_iff_dvd {n p : ℕ} (hn : n ≠ 0) (hp : Prime p) : p ∈ factors n ↔ p ∣ n :=
⟨fun h => prod_factors hn ▸ List.dvd_prod h, fun h =>
mem_list_primes_of_dvd_prod (prime_iff.mp hp) (fun _ h => prime_iff.mp (prime_of_mem_factors h))
((prod_factors hn).symm ▸ h)⟩
#align nat.mem_factors_iff_dvd Nat.mem_factors_iff_dvd
theorem dvd_of_mem_factors {n p : ℕ} (h : p ∈ n.factors) : p ∣ n := by
rcases n.eq_zero_or_pos with (rfl | hn)
· exact dvd_zero p
· rwa [← mem_factors_iff_dvd hn.ne' (prime_of_mem_factors h)]
#align nat.dvd_of_mem_factors Nat.dvd_of_mem_factors
theorem mem_factors {n p} (hn : n ≠ 0) : p ∈ factors n ↔ Prime p ∧ p ∣ n :=
⟨fun h => ⟨prime_of_mem_factors h, dvd_of_mem_factors h⟩, fun ⟨hprime, hdvd⟩ =>
(mem_factors_iff_dvd hn hprime).mpr hdvd⟩
#align nat.mem_factors Nat.mem_factors
@[simp] lemma mem_factors' {n p} : p ∈ n.factors ↔ p.Prime ∧ p ∣ n ∧ n ≠ 0 := by
cases n <;> simp [mem_factors, *]
theorem le_of_mem_factors {n p : ℕ} (h : p ∈ n.factors) : p ≤ n := by
rcases n.eq_zero_or_pos with (rfl | hn)
· rw [factors_zero] at h
cases h
· exact le_of_dvd hn (dvd_of_mem_factors h)
#align nat.le_of_mem_factors Nat.le_of_mem_factors
theorem factors_unique {n : ℕ} {l : List ℕ} (h₁ : prod l = n) (h₂ : ∀ p ∈ l, Prime p) :
l ~ factors n := by
refine perm_of_prod_eq_prod ?_ ?_ ?_
· rw [h₁]
refine (prod_factors ?_).symm
rintro rfl
rw [prod_eq_zero_iff] at h₁
exact Prime.ne_zero (h₂ 0 h₁) rfl
· simp_rw [← prime_iff]
exact h₂
· simp_rw [← prime_iff]
exact fun p => prime_of_mem_factors
#align nat.factors_unique Nat.factors_unique
theorem Prime.factors_pow {p : ℕ} (hp : p.Prime) (n : ℕ) :
(p ^ n).factors = List.replicate n p := by
symm
rw [← List.replicate_perm]
apply Nat.factors_unique (List.prod_replicate n p)
intro q hq
rwa [eq_of_mem_replicate hq]
#align nat.prime.factors_pow Nat.Prime.factors_pow
theorem eq_prime_pow_of_unique_prime_dvd {n p : ℕ} (hpos : n ≠ 0)
(h : ∀ {d}, Nat.Prime d → d ∣ n → d = p) : n = p ^ n.factors.length := by
set k := n.factors.length
rw [← prod_factors hpos, ← prod_replicate k p,
eq_replicate_of_mem fun d hd => h (prime_of_mem_factors hd) (dvd_of_mem_factors hd)]
#align nat.eq_prime_pow_of_unique_prime_dvd Nat.eq_prime_pow_of_unique_prime_dvd
theorem perm_factors_mul {a b : ℕ} (ha : a ≠ 0) (hb : b ≠ 0) :
(a * b).factors ~ a.factors ++ b.factors := by
refine (factors_unique ?_ ?_).symm
· rw [List.prod_append, prod_factors ha, prod_factors hb]
· intro p hp
rw [List.mem_append] at hp
cases' hp with hp' hp' <;> exact prime_of_mem_factors hp'
#align nat.perm_factors_mul Nat.perm_factors_mul
theorem perm_factors_mul_of_coprime {a b : ℕ} (hab : Coprime a b) :
(a * b).factors ~ a.factors ++ b.factors := by
rcases a.eq_zero_or_pos with (rfl | ha)
· simp [(coprime_zero_left _).mp hab]
rcases b.eq_zero_or_pos with (rfl | hb)
· simp [(coprime_zero_right _).mp hab]
exact perm_factors_mul ha.ne' hb.ne'
#align nat.perm_factors_mul_of_coprime Nat.perm_factors_mul_of_coprime
theorem factors_sublist_right {n k : ℕ} (h : k ≠ 0) : n.factors <+ (n * k).factors := by
cases' n with hn
· simp [zero_mul]
apply sublist_of_subperm_of_sorted _ (factors_sorted _) (factors_sorted _)
simp only [(perm_factors_mul (Nat.succ_ne_zero _) h).subperm_left]
exact (sublist_append_left _ _).subperm
#align nat.factors_sublist_right Nat.factors_sublist_right
theorem factors_sublist_of_dvd {n k : ℕ} (h : n ∣ k) (h' : k ≠ 0) : n.factors <+ k.factors := by
obtain ⟨a, rfl⟩ := h
exact factors_sublist_right (right_ne_zero_of_mul h')
#align nat.factors_sublist_of_dvd Nat.factors_sublist_of_dvd
theorem factors_subset_right {n k : ℕ} (h : k ≠ 0) : n.factors ⊆ (n * k).factors :=
(factors_sublist_right h).subset
#align nat.factors_subset_right Nat.factors_subset_right
theorem factors_subset_of_dvd {n k : ℕ} (h : n ∣ k) (h' : k ≠ 0) : n.factors ⊆ k.factors :=
(factors_sublist_of_dvd h h').subset
#align nat.factors_subset_of_dvd Nat.factors_subset_of_dvd
theorem dvd_of_factors_subperm {a b : ℕ} (ha : a ≠ 0) (h : a.factors <+~ b.factors) : a ∣ b := by
rcases b.eq_zero_or_pos with (rfl | hb)
· exact dvd_zero _
rcases a with (_ | _ | a)
· exact (ha rfl).elim
· exact one_dvd _
-- Porting note: previous proof
--use (b.factors.diff a.succ.succ.factors).prod
use (@List.diff _ instBEqOfDecidableEq b.factors a.succ.succ.factors).prod
nth_rw 1 [← Nat.prod_factors ha]
rw [← List.prod_append,
List.Perm.prod_eq <| List.subperm_append_diff_self_of_count_le <| List.subperm_ext_iff.mp h,
Nat.prod_factors hb.ne']
#align nat.dvd_of_factors_subperm Nat.dvd_of_factors_subperm
theorem replicate_subperm_factors_iff {a b n : ℕ} (ha : Prime a) (hb : b ≠ 0) :
replicate n a <+~ factors b ↔ a ^ n ∣ b := by
induction n generalizing b with
| zero => simp
| succ n ih =>
constructor
· rw [List.subperm_iff]
rintro ⟨u, hu1, hu2⟩
rw [← Nat.prod_factors hb, ← hu1.prod_eq, ← prod_replicate]
exact hu2.prod_dvd_prod
· rintro ⟨c, rfl⟩
rw [Ne, pow_succ', mul_assoc, mul_eq_zero, _root_.not_or] at hb
rw [pow_succ', mul_assoc, replicate_succ, (Nat.perm_factors_mul hb.1 hb.2).subperm_left,
factors_prime ha, singleton_append, subperm_cons, ih hb.2]
exact dvd_mul_right _ _
end
| Mathlib/Data/Nat/Factors.lean | 278 | 281 | theorem mem_factors_mul {a b : ℕ} (ha : a ≠ 0) (hb : b ≠ 0) {p : ℕ} :
p ∈ (a * b).factors ↔ p ∈ a.factors ∨ p ∈ b.factors := by |
rw [mem_factors (mul_ne_zero ha hb), mem_factors ha, mem_factors hb, ← and_or_left]
simpa only [and_congr_right_iff] using Prime.dvd_mul
|
import Mathlib.Algebra.IsPrimePow
import Mathlib.SetTheory.Cardinal.Ordinal
import Mathlib.Tactic.WLOG
#align_import set_theory.cardinal.divisibility from "leanprover-community/mathlib"@"ea050b44c0f9aba9d16a948c7cc7d2e7c8493567"
namespace Cardinal
open Cardinal
universe u
variable {a b : Cardinal.{u}} {n m : ℕ}
@[simp]
| Mathlib/SetTheory/Cardinal/Divisibility.lean | 43 | 58 | theorem isUnit_iff : IsUnit a ↔ a = 1 := by |
refine
⟨fun h => ?_, by
rintro rfl
exact isUnit_one⟩
rcases eq_or_ne a 0 with (rfl | ha)
· exact (not_isUnit_zero h).elim
rw [isUnit_iff_forall_dvd] at h
cases' h 1 with t ht
rw [eq_comm, mul_eq_one_iff'] at ht
· exact ht.1
· exact one_le_iff_ne_zero.mpr ha
· apply one_le_iff_ne_zero.mpr
intro h
rw [h, mul_zero] at ht
exact zero_ne_one ht
|
import Mathlib.Logic.Pairwise
import Mathlib.Order.CompleteBooleanAlgebra
import Mathlib.Order.Directed
import Mathlib.Order.GaloisConnection
#align_import data.set.lattice from "leanprover-community/mathlib"@"b86832321b586c6ac23ef8cdef6a7a27e42b13bd"
open Function Set
universe u
variable {α β γ : Type*} {ι ι' ι₂ : Sort*} {κ κ₁ κ₂ : ι → Sort*} {κ' : ι' → Sort*}
namespace Set
theorem mem_iUnion₂ {x : γ} {s : ∀ i, κ i → Set γ} : (x ∈ ⋃ (i) (j), s i j) ↔ ∃ i j, x ∈ s i j := by
simp_rw [mem_iUnion]
#align set.mem_Union₂ Set.mem_iUnion₂
theorem mem_iInter₂ {x : γ} {s : ∀ i, κ i → Set γ} : (x ∈ ⋂ (i) (j), s i j) ↔ ∀ i j, x ∈ s i j := by
simp_rw [mem_iInter]
#align set.mem_Inter₂ Set.mem_iInter₂
theorem mem_iUnion_of_mem {s : ι → Set α} {a : α} (i : ι) (ha : a ∈ s i) : a ∈ ⋃ i, s i :=
mem_iUnion.2 ⟨i, ha⟩
#align set.mem_Union_of_mem Set.mem_iUnion_of_mem
theorem mem_iUnion₂_of_mem {s : ∀ i, κ i → Set α} {a : α} {i : ι} (j : κ i) (ha : a ∈ s i j) :
a ∈ ⋃ (i) (j), s i j :=
mem_iUnion₂.2 ⟨i, j, ha⟩
#align set.mem_Union₂_of_mem Set.mem_iUnion₂_of_mem
theorem mem_iInter_of_mem {s : ι → Set α} {a : α} (h : ∀ i, a ∈ s i) : a ∈ ⋂ i, s i :=
mem_iInter.2 h
#align set.mem_Inter_of_mem Set.mem_iInter_of_mem
theorem mem_iInter₂_of_mem {s : ∀ i, κ i → Set α} {a : α} (h : ∀ i j, a ∈ s i j) :
a ∈ ⋂ (i) (j), s i j :=
mem_iInter₂.2 h
#align set.mem_Inter₂_of_mem Set.mem_iInter₂_of_mem
instance completeAtomicBooleanAlgebra : CompleteAtomicBooleanAlgebra (Set α) :=
{ instBooleanAlgebraSet with
le_sSup := fun s t t_in a a_in => ⟨t, t_in, a_in⟩
sSup_le := fun s t h a ⟨t', ⟨t'_in, a_in⟩⟩ => h t' t'_in a_in
le_sInf := fun s t h a a_in t' t'_in => h t' t'_in a_in
sInf_le := fun s t t_in a h => h _ t_in
iInf_iSup_eq := by intros; ext; simp [Classical.skolem] }
instance : OrderTop (Set α) where
top := univ
le_top := by simp
@[congr]
theorem iUnion_congr_Prop {p q : Prop} {f₁ : p → Set α} {f₂ : q → Set α} (pq : p ↔ q)
(f : ∀ x, f₁ (pq.mpr x) = f₂ x) : iUnion f₁ = iUnion f₂ :=
iSup_congr_Prop pq f
#align set.Union_congr_Prop Set.iUnion_congr_Prop
@[congr]
theorem iInter_congr_Prop {p q : Prop} {f₁ : p → Set α} {f₂ : q → Set α} (pq : p ↔ q)
(f : ∀ x, f₁ (pq.mpr x) = f₂ x) : iInter f₁ = iInter f₂ :=
iInf_congr_Prop pq f
#align set.Inter_congr_Prop Set.iInter_congr_Prop
theorem iUnion_plift_up (f : PLift ι → Set α) : ⋃ i, f (PLift.up i) = ⋃ i, f i :=
iSup_plift_up _
#align set.Union_plift_up Set.iUnion_plift_up
theorem iUnion_plift_down (f : ι → Set α) : ⋃ i, f (PLift.down i) = ⋃ i, f i :=
iSup_plift_down _
#align set.Union_plift_down Set.iUnion_plift_down
theorem iInter_plift_up (f : PLift ι → Set α) : ⋂ i, f (PLift.up i) = ⋂ i, f i :=
iInf_plift_up _
#align set.Inter_plift_up Set.iInter_plift_up
theorem iInter_plift_down (f : ι → Set α) : ⋂ i, f (PLift.down i) = ⋂ i, f i :=
iInf_plift_down _
#align set.Inter_plift_down Set.iInter_plift_down
theorem iUnion_eq_if {p : Prop} [Decidable p] (s : Set α) : ⋃ _ : p, s = if p then s else ∅ :=
iSup_eq_if _
#align set.Union_eq_if Set.iUnion_eq_if
theorem iUnion_eq_dif {p : Prop} [Decidable p] (s : p → Set α) :
⋃ h : p, s h = if h : p then s h else ∅ :=
iSup_eq_dif _
#align set.Union_eq_dif Set.iUnion_eq_dif
theorem iInter_eq_if {p : Prop} [Decidable p] (s : Set α) : ⋂ _ : p, s = if p then s else univ :=
iInf_eq_if _
#align set.Inter_eq_if Set.iInter_eq_if
theorem iInf_eq_dif {p : Prop} [Decidable p] (s : p → Set α) :
⋂ h : p, s h = if h : p then s h else univ :=
_root_.iInf_eq_dif _
#align set.Infi_eq_dif Set.iInf_eq_dif
theorem exists_set_mem_of_union_eq_top {ι : Type*} (t : Set ι) (s : ι → Set β)
(w : ⋃ i ∈ t, s i = ⊤) (x : β) : ∃ i ∈ t, x ∈ s i := by
have p : x ∈ ⊤ := Set.mem_univ x
rw [← w, Set.mem_iUnion] at p
simpa using p
#align set.exists_set_mem_of_union_eq_top Set.exists_set_mem_of_union_eq_top
theorem nonempty_of_union_eq_top_of_nonempty {ι : Type*} (t : Set ι) (s : ι → Set α)
(H : Nonempty α) (w : ⋃ i ∈ t, s i = ⊤) : t.Nonempty := by
obtain ⟨x, m, -⟩ := exists_set_mem_of_union_eq_top t s w H.some
exact ⟨x, m⟩
#align set.nonempty_of_union_eq_top_of_nonempty Set.nonempty_of_union_eq_top_of_nonempty
theorem nonempty_of_nonempty_iUnion
{s : ι → Set α} (h_Union : (⋃ i, s i).Nonempty) : Nonempty ι := by
obtain ⟨x, hx⟩ := h_Union
exact ⟨Classical.choose <| mem_iUnion.mp hx⟩
theorem nonempty_of_nonempty_iUnion_eq_univ
{s : ι → Set α} [Nonempty α] (h_Union : ⋃ i, s i = univ) : Nonempty ι :=
nonempty_of_nonempty_iUnion (s := s) (by simpa only [h_Union] using univ_nonempty)
theorem setOf_exists (p : ι → β → Prop) : { x | ∃ i, p i x } = ⋃ i, { x | p i x } :=
ext fun _ => mem_iUnion.symm
#align set.set_of_exists Set.setOf_exists
theorem setOf_forall (p : ι → β → Prop) : { x | ∀ i, p i x } = ⋂ i, { x | p i x } :=
ext fun _ => mem_iInter.symm
#align set.set_of_forall Set.setOf_forall
theorem iUnion_subset {s : ι → Set α} {t : Set α} (h : ∀ i, s i ⊆ t) : ⋃ i, s i ⊆ t :=
iSup_le h
#align set.Union_subset Set.iUnion_subset
theorem iUnion₂_subset {s : ∀ i, κ i → Set α} {t : Set α} (h : ∀ i j, s i j ⊆ t) :
⋃ (i) (j), s i j ⊆ t :=
iUnion_subset fun x => iUnion_subset (h x)
#align set.Union₂_subset Set.iUnion₂_subset
theorem subset_iInter {t : Set β} {s : ι → Set β} (h : ∀ i, t ⊆ s i) : t ⊆ ⋂ i, s i :=
le_iInf h
#align set.subset_Inter Set.subset_iInter
theorem subset_iInter₂ {s : Set α} {t : ∀ i, κ i → Set α} (h : ∀ i j, s ⊆ t i j) :
s ⊆ ⋂ (i) (j), t i j :=
subset_iInter fun x => subset_iInter <| h x
#align set.subset_Inter₂ Set.subset_iInter₂
@[simp]
theorem iUnion_subset_iff {s : ι → Set α} {t : Set α} : ⋃ i, s i ⊆ t ↔ ∀ i, s i ⊆ t :=
⟨fun h _ => Subset.trans (le_iSup s _) h, iUnion_subset⟩
#align set.Union_subset_iff Set.iUnion_subset_iff
theorem iUnion₂_subset_iff {s : ∀ i, κ i → Set α} {t : Set α} :
⋃ (i) (j), s i j ⊆ t ↔ ∀ i j, s i j ⊆ t := by simp_rw [iUnion_subset_iff]
#align set.Union₂_subset_iff Set.iUnion₂_subset_iff
@[simp]
theorem subset_iInter_iff {s : Set α} {t : ι → Set α} : (s ⊆ ⋂ i, t i) ↔ ∀ i, s ⊆ t i :=
le_iInf_iff
#align set.subset_Inter_iff Set.subset_iInter_iff
-- Porting note (#10618): removing `simp`. `simp` can prove it
theorem subset_iInter₂_iff {s : Set α} {t : ∀ i, κ i → Set α} :
(s ⊆ ⋂ (i) (j), t i j) ↔ ∀ i j, s ⊆ t i j := by simp_rw [subset_iInter_iff]
#align set.subset_Inter₂_iff Set.subset_iInter₂_iff
theorem subset_iUnion : ∀ (s : ι → Set β) (i : ι), s i ⊆ ⋃ i, s i :=
le_iSup
#align set.subset_Union Set.subset_iUnion
theorem iInter_subset : ∀ (s : ι → Set β) (i : ι), ⋂ i, s i ⊆ s i :=
iInf_le
#align set.Inter_subset Set.iInter_subset
theorem subset_iUnion₂ {s : ∀ i, κ i → Set α} (i : ι) (j : κ i) : s i j ⊆ ⋃ (i') (j'), s i' j' :=
le_iSup₂ i j
#align set.subset_Union₂ Set.subset_iUnion₂
theorem iInter₂_subset {s : ∀ i, κ i → Set α} (i : ι) (j : κ i) : ⋂ (i) (j), s i j ⊆ s i j :=
iInf₂_le i j
#align set.Inter₂_subset Set.iInter₂_subset
theorem subset_iUnion_of_subset {s : Set α} {t : ι → Set α} (i : ι) (h : s ⊆ t i) : s ⊆ ⋃ i, t i :=
le_iSup_of_le i h
#align set.subset_Union_of_subset Set.subset_iUnion_of_subset
theorem iInter_subset_of_subset {s : ι → Set α} {t : Set α} (i : ι) (h : s i ⊆ t) :
⋂ i, s i ⊆ t :=
iInf_le_of_le i h
#align set.Inter_subset_of_subset Set.iInter_subset_of_subset
theorem subset_iUnion₂_of_subset {s : Set α} {t : ∀ i, κ i → Set α} (i : ι) (j : κ i)
(h : s ⊆ t i j) : s ⊆ ⋃ (i) (j), t i j :=
le_iSup₂_of_le i j h
#align set.subset_Union₂_of_subset Set.subset_iUnion₂_of_subset
theorem iInter₂_subset_of_subset {s : ∀ i, κ i → Set α} {t : Set α} (i : ι) (j : κ i)
(h : s i j ⊆ t) : ⋂ (i) (j), s i j ⊆ t :=
iInf₂_le_of_le i j h
#align set.Inter₂_subset_of_subset Set.iInter₂_subset_of_subset
theorem iUnion_mono {s t : ι → Set α} (h : ∀ i, s i ⊆ t i) : ⋃ i, s i ⊆ ⋃ i, t i :=
iSup_mono h
#align set.Union_mono Set.iUnion_mono
@[gcongr]
theorem iUnion_mono'' {s t : ι → Set α} (h : ∀ i, s i ⊆ t i) : iUnion s ⊆ iUnion t :=
iSup_mono h
theorem iUnion₂_mono {s t : ∀ i, κ i → Set α} (h : ∀ i j, s i j ⊆ t i j) :
⋃ (i) (j), s i j ⊆ ⋃ (i) (j), t i j :=
iSup₂_mono h
#align set.Union₂_mono Set.iUnion₂_mono
theorem iInter_mono {s t : ι → Set α} (h : ∀ i, s i ⊆ t i) : ⋂ i, s i ⊆ ⋂ i, t i :=
iInf_mono h
#align set.Inter_mono Set.iInter_mono
@[gcongr]
theorem iInter_mono'' {s t : ι → Set α} (h : ∀ i, s i ⊆ t i) : iInter s ⊆ iInter t :=
iInf_mono h
theorem iInter₂_mono {s t : ∀ i, κ i → Set α} (h : ∀ i j, s i j ⊆ t i j) :
⋂ (i) (j), s i j ⊆ ⋂ (i) (j), t i j :=
iInf₂_mono h
#align set.Inter₂_mono Set.iInter₂_mono
theorem iUnion_mono' {s : ι → Set α} {t : ι₂ → Set α} (h : ∀ i, ∃ j, s i ⊆ t j) :
⋃ i, s i ⊆ ⋃ i, t i :=
iSup_mono' h
#align set.Union_mono' Set.iUnion_mono'
theorem iUnion₂_mono' {s : ∀ i, κ i → Set α} {t : ∀ i', κ' i' → Set α}
(h : ∀ i j, ∃ i' j', s i j ⊆ t i' j') : ⋃ (i) (j), s i j ⊆ ⋃ (i') (j'), t i' j' :=
iSup₂_mono' h
#align set.Union₂_mono' Set.iUnion₂_mono'
theorem iInter_mono' {s : ι → Set α} {t : ι' → Set α} (h : ∀ j, ∃ i, s i ⊆ t j) :
⋂ i, s i ⊆ ⋂ j, t j :=
Set.subset_iInter fun j =>
let ⟨i, hi⟩ := h j
iInter_subset_of_subset i hi
#align set.Inter_mono' Set.iInter_mono'
theorem iInter₂_mono' {s : ∀ i, κ i → Set α} {t : ∀ i', κ' i' → Set α}
(h : ∀ i' j', ∃ i j, s i j ⊆ t i' j') : ⋂ (i) (j), s i j ⊆ ⋂ (i') (j'), t i' j' :=
subset_iInter₂_iff.2 fun i' j' =>
let ⟨_, _, hst⟩ := h i' j'
(iInter₂_subset _ _).trans hst
#align set.Inter₂_mono' Set.iInter₂_mono'
theorem iUnion₂_subset_iUnion (κ : ι → Sort*) (s : ι → Set α) :
⋃ (i) (_ : κ i), s i ⊆ ⋃ i, s i :=
iUnion_mono fun _ => iUnion_subset fun _ => Subset.rfl
#align set.Union₂_subset_Union Set.iUnion₂_subset_iUnion
theorem iInter_subset_iInter₂ (κ : ι → Sort*) (s : ι → Set α) :
⋂ i, s i ⊆ ⋂ (i) (_ : κ i), s i :=
iInter_mono fun _ => subset_iInter fun _ => Subset.rfl
#align set.Inter_subset_Inter₂ Set.iInter_subset_iInter₂
theorem iUnion_setOf (P : ι → α → Prop) : ⋃ i, { x : α | P i x } = { x : α | ∃ i, P i x } := by
ext
exact mem_iUnion
#align set.Union_set_of Set.iUnion_setOf
theorem iInter_setOf (P : ι → α → Prop) : ⋂ i, { x : α | P i x } = { x : α | ∀ i, P i x } := by
ext
exact mem_iInter
#align set.Inter_set_of Set.iInter_setOf
theorem iUnion_congr_of_surjective {f : ι → Set α} {g : ι₂ → Set α} (h : ι → ι₂) (h1 : Surjective h)
(h2 : ∀ x, g (h x) = f x) : ⋃ x, f x = ⋃ y, g y :=
h1.iSup_congr h h2
#align set.Union_congr_of_surjective Set.iUnion_congr_of_surjective
theorem iInter_congr_of_surjective {f : ι → Set α} {g : ι₂ → Set α} (h : ι → ι₂) (h1 : Surjective h)
(h2 : ∀ x, g (h x) = f x) : ⋂ x, f x = ⋂ y, g y :=
h1.iInf_congr h h2
#align set.Inter_congr_of_surjective Set.iInter_congr_of_surjective
lemma iUnion_congr {s t : ι → Set α} (h : ∀ i, s i = t i) : ⋃ i, s i = ⋃ i, t i := iSup_congr h
#align set.Union_congr Set.iUnion_congr
lemma iInter_congr {s t : ι → Set α} (h : ∀ i, s i = t i) : ⋂ i, s i = ⋂ i, t i := iInf_congr h
#align set.Inter_congr Set.iInter_congr
lemma iUnion₂_congr {s t : ∀ i, κ i → Set α} (h : ∀ i j, s i j = t i j) :
⋃ (i) (j), s i j = ⋃ (i) (j), t i j :=
iUnion_congr fun i => iUnion_congr <| h i
#align set.Union₂_congr Set.iUnion₂_congr
lemma iInter₂_congr {s t : ∀ i, κ i → Set α} (h : ∀ i j, s i j = t i j) :
⋂ (i) (j), s i j = ⋂ (i) (j), t i j :=
iInter_congr fun i => iInter_congr <| h i
#align set.Inter₂_congr Set.iInter₂_congr
@[simp]
theorem compl_iUnion (s : ι → Set β) : (⋃ i, s i)ᶜ = ⋂ i, (s i)ᶜ :=
compl_iSup
#align set.compl_Union Set.compl_iUnion
theorem compl_iUnion₂ (s : ∀ i, κ i → Set α) : (⋃ (i) (j), s i j)ᶜ = ⋂ (i) (j), (s i j)ᶜ := by
simp_rw [compl_iUnion]
#align set.compl_Union₂ Set.compl_iUnion₂
@[simp]
theorem compl_iInter (s : ι → Set β) : (⋂ i, s i)ᶜ = ⋃ i, (s i)ᶜ :=
compl_iInf
#align set.compl_Inter Set.compl_iInter
theorem compl_iInter₂ (s : ∀ i, κ i → Set α) : (⋂ (i) (j), s i j)ᶜ = ⋃ (i) (j), (s i j)ᶜ := by
simp_rw [compl_iInter]
#align set.compl_Inter₂ Set.compl_iInter₂
-- classical -- complete_boolean_algebra
theorem iUnion_eq_compl_iInter_compl (s : ι → Set β) : ⋃ i, s i = (⋂ i, (s i)ᶜ)ᶜ := by
simp only [compl_iInter, compl_compl]
#align set.Union_eq_compl_Inter_compl Set.iUnion_eq_compl_iInter_compl
-- classical -- complete_boolean_algebra
theorem iInter_eq_compl_iUnion_compl (s : ι → Set β) : ⋂ i, s i = (⋃ i, (s i)ᶜ)ᶜ := by
simp only [compl_iUnion, compl_compl]
#align set.Inter_eq_compl_Union_compl Set.iInter_eq_compl_iUnion_compl
theorem inter_iUnion (s : Set β) (t : ι → Set β) : (s ∩ ⋃ i, t i) = ⋃ i, s ∩ t i :=
inf_iSup_eq _ _
#align set.inter_Union Set.inter_iUnion
theorem iUnion_inter (s : Set β) (t : ι → Set β) : (⋃ i, t i) ∩ s = ⋃ i, t i ∩ s :=
iSup_inf_eq _ _
#align set.Union_inter Set.iUnion_inter
theorem iUnion_union_distrib (s : ι → Set β) (t : ι → Set β) :
⋃ i, s i ∪ t i = (⋃ i, s i) ∪ ⋃ i, t i :=
iSup_sup_eq
#align set.Union_union_distrib Set.iUnion_union_distrib
theorem iInter_inter_distrib (s : ι → Set β) (t : ι → Set β) :
⋂ i, s i ∩ t i = (⋂ i, s i) ∩ ⋂ i, t i :=
iInf_inf_eq
#align set.Inter_inter_distrib Set.iInter_inter_distrib
theorem union_iUnion [Nonempty ι] (s : Set β) (t : ι → Set β) : (s ∪ ⋃ i, t i) = ⋃ i, s ∪ t i :=
sup_iSup
#align set.union_Union Set.union_iUnion
theorem iUnion_union [Nonempty ι] (s : Set β) (t : ι → Set β) : (⋃ i, t i) ∪ s = ⋃ i, t i ∪ s :=
iSup_sup
#align set.Union_union Set.iUnion_union
theorem inter_iInter [Nonempty ι] (s : Set β) (t : ι → Set β) : (s ∩ ⋂ i, t i) = ⋂ i, s ∩ t i :=
inf_iInf
#align set.inter_Inter Set.inter_iInter
theorem iInter_inter [Nonempty ι] (s : Set β) (t : ι → Set β) : (⋂ i, t i) ∩ s = ⋂ i, t i ∩ s :=
iInf_inf
#align set.Inter_inter Set.iInter_inter
-- classical
theorem union_iInter (s : Set β) (t : ι → Set β) : (s ∪ ⋂ i, t i) = ⋂ i, s ∪ t i :=
sup_iInf_eq _ _
#align set.union_Inter Set.union_iInter
theorem iInter_union (s : ι → Set β) (t : Set β) : (⋂ i, s i) ∪ t = ⋂ i, s i ∪ t :=
iInf_sup_eq _ _
#align set.Inter_union Set.iInter_union
theorem iUnion_diff (s : Set β) (t : ι → Set β) : (⋃ i, t i) \ s = ⋃ i, t i \ s :=
iUnion_inter _ _
#align set.Union_diff Set.iUnion_diff
theorem diff_iUnion [Nonempty ι] (s : Set β) (t : ι → Set β) : (s \ ⋃ i, t i) = ⋂ i, s \ t i := by
rw [diff_eq, compl_iUnion, inter_iInter]; rfl
#align set.diff_Union Set.diff_iUnion
theorem diff_iInter (s : Set β) (t : ι → Set β) : (s \ ⋂ i, t i) = ⋃ i, s \ t i := by
rw [diff_eq, compl_iInter, inter_iUnion]; rfl
#align set.diff_Inter Set.diff_iInter
theorem iUnion_inter_subset {ι α} {s t : ι → Set α} : ⋃ i, s i ∩ t i ⊆ (⋃ i, s i) ∩ ⋃ i, t i :=
le_iSup_inf_iSup s t
#align set.Union_inter_subset Set.iUnion_inter_subset
theorem iUnion_inter_of_monotone {ι α} [Preorder ι] [IsDirected ι (· ≤ ·)] {s t : ι → Set α}
(hs : Monotone s) (ht : Monotone t) : ⋃ i, s i ∩ t i = (⋃ i, s i) ∩ ⋃ i, t i :=
iSup_inf_of_monotone hs ht
#align set.Union_inter_of_monotone Set.iUnion_inter_of_monotone
theorem iUnion_inter_of_antitone {ι α} [Preorder ι] [IsDirected ι (swap (· ≤ ·))] {s t : ι → Set α}
(hs : Antitone s) (ht : Antitone t) : ⋃ i, s i ∩ t i = (⋃ i, s i) ∩ ⋃ i, t i :=
iSup_inf_of_antitone hs ht
#align set.Union_inter_of_antitone Set.iUnion_inter_of_antitone
theorem iInter_union_of_monotone {ι α} [Preorder ι] [IsDirected ι (swap (· ≤ ·))] {s t : ι → Set α}
(hs : Monotone s) (ht : Monotone t) : ⋂ i, s i ∪ t i = (⋂ i, s i) ∪ ⋂ i, t i :=
iInf_sup_of_monotone hs ht
#align set.Inter_union_of_monotone Set.iInter_union_of_monotone
theorem iInter_union_of_antitone {ι α} [Preorder ι] [IsDirected ι (· ≤ ·)] {s t : ι → Set α}
(hs : Antitone s) (ht : Antitone t) : ⋂ i, s i ∪ t i = (⋂ i, s i) ∪ ⋂ i, t i :=
iInf_sup_of_antitone hs ht
#align set.Inter_union_of_antitone Set.iInter_union_of_antitone
theorem iUnion_iInter_subset {s : ι → ι' → Set α} : (⋃ j, ⋂ i, s i j) ⊆ ⋂ i, ⋃ j, s i j :=
iSup_iInf_le_iInf_iSup (flip s)
#align set.Union_Inter_subset Set.iUnion_iInter_subset
theorem iUnion_option {ι} (s : Option ι → Set α) : ⋃ o, s o = s none ∪ ⋃ i, s (some i) :=
iSup_option s
#align set.Union_option Set.iUnion_option
theorem iInter_option {ι} (s : Option ι → Set α) : ⋂ o, s o = s none ∩ ⋂ i, s (some i) :=
iInf_option s
#align set.Inter_option Set.iInter_option
section
variable (p : ι → Prop) [DecidablePred p]
theorem iUnion_dite (f : ∀ i, p i → Set α) (g : ∀ i, ¬p i → Set α) :
⋃ i, (if h : p i then f i h else g i h) = (⋃ (i) (h : p i), f i h) ∪ ⋃ (i) (h : ¬p i), g i h :=
iSup_dite _ _ _
#align set.Union_dite Set.iUnion_dite
theorem iUnion_ite (f g : ι → Set α) :
⋃ i, (if p i then f i else g i) = (⋃ (i) (_ : p i), f i) ∪ ⋃ (i) (_ : ¬p i), g i :=
iUnion_dite _ _ _
#align set.Union_ite Set.iUnion_ite
theorem iInter_dite (f : ∀ i, p i → Set α) (g : ∀ i, ¬p i → Set α) :
⋂ i, (if h : p i then f i h else g i h) = (⋂ (i) (h : p i), f i h) ∩ ⋂ (i) (h : ¬p i), g i h :=
iInf_dite _ _ _
#align set.Inter_dite Set.iInter_dite
theorem iInter_ite (f g : ι → Set α) :
⋂ i, (if p i then f i else g i) = (⋂ (i) (_ : p i), f i) ∩ ⋂ (i) (_ : ¬p i), g i :=
iInter_dite _ _ _
#align set.Inter_ite Set.iInter_ite
end
theorem image_projection_prod {ι : Type*} {α : ι → Type*} {v : ∀ i : ι, Set (α i)}
(hv : (pi univ v).Nonempty) (i : ι) :
((fun x : ∀ i : ι, α i => x i) '' ⋂ k, (fun x : ∀ j : ι, α j => x k) ⁻¹' v k) = v i := by
classical
apply Subset.antisymm
· simp [iInter_subset]
· intro y y_in
simp only [mem_image, mem_iInter, mem_preimage]
rcases hv with ⟨z, hz⟩
refine ⟨Function.update z i y, ?_, update_same i y z⟩
rw [@forall_update_iff ι α _ z i y fun i t => t ∈ v i]
exact ⟨y_in, fun j _ => by simpa using hz j⟩
#align set.image_projection_prod Set.image_projection_prod
theorem iInter_false {s : False → Set α} : iInter s = univ :=
iInf_false
#align set.Inter_false Set.iInter_false
theorem iUnion_false {s : False → Set α} : iUnion s = ∅ :=
iSup_false
#align set.Union_false Set.iUnion_false
@[simp]
theorem iInter_true {s : True → Set α} : iInter s = s trivial :=
iInf_true
#align set.Inter_true Set.iInter_true
@[simp]
theorem iUnion_true {s : True → Set α} : iUnion s = s trivial :=
iSup_true
#align set.Union_true Set.iUnion_true
@[simp]
theorem iInter_exists {p : ι → Prop} {f : Exists p → Set α} :
⋂ x, f x = ⋂ (i) (h : p i), f ⟨i, h⟩ :=
iInf_exists
#align set.Inter_exists Set.iInter_exists
@[simp]
theorem iUnion_exists {p : ι → Prop} {f : Exists p → Set α} :
⋃ x, f x = ⋃ (i) (h : p i), f ⟨i, h⟩ :=
iSup_exists
#align set.Union_exists Set.iUnion_exists
@[simp]
theorem iUnion_empty : (⋃ _ : ι, ∅ : Set α) = ∅ :=
iSup_bot
#align set.Union_empty Set.iUnion_empty
@[simp]
theorem iInter_univ : (⋂ _ : ι, univ : Set α) = univ :=
iInf_top
#align set.Inter_univ Set.iInter_univ
section
variable {s : ι → Set α}
@[simp]
theorem iUnion_eq_empty : ⋃ i, s i = ∅ ↔ ∀ i, s i = ∅ :=
iSup_eq_bot
#align set.Union_eq_empty Set.iUnion_eq_empty
@[simp]
theorem iInter_eq_univ : ⋂ i, s i = univ ↔ ∀ i, s i = univ :=
iInf_eq_top
#align set.Inter_eq_univ Set.iInter_eq_univ
@[simp]
theorem nonempty_iUnion : (⋃ i, s i).Nonempty ↔ ∃ i, (s i).Nonempty := by
simp [nonempty_iff_ne_empty]
#align set.nonempty_Union Set.nonempty_iUnion
-- Porting note (#10618): removing `simp`. `simp` can prove it
theorem nonempty_biUnion {t : Set α} {s : α → Set β} :
(⋃ i ∈ t, s i).Nonempty ↔ ∃ i ∈ t, (s i).Nonempty := by simp
#align set.nonempty_bUnion Set.nonempty_biUnion
theorem iUnion_nonempty_index (s : Set α) (t : s.Nonempty → Set β) :
⋃ h, t h = ⋃ x ∈ s, t ⟨x, ‹_›⟩ :=
iSup_exists
#align set.Union_nonempty_index Set.iUnion_nonempty_index
end
@[simp]
theorem iInter_iInter_eq_left {b : β} {s : ∀ x : β, x = b → Set α} :
⋂ (x) (h : x = b), s x h = s b rfl :=
iInf_iInf_eq_left
#align set.Inter_Inter_eq_left Set.iInter_iInter_eq_left
@[simp]
theorem iInter_iInter_eq_right {b : β} {s : ∀ x : β, b = x → Set α} :
⋂ (x) (h : b = x), s x h = s b rfl :=
iInf_iInf_eq_right
#align set.Inter_Inter_eq_right Set.iInter_iInter_eq_right
@[simp]
theorem iUnion_iUnion_eq_left {b : β} {s : ∀ x : β, x = b → Set α} :
⋃ (x) (h : x = b), s x h = s b rfl :=
iSup_iSup_eq_left
#align set.Union_Union_eq_left Set.iUnion_iUnion_eq_left
@[simp]
theorem iUnion_iUnion_eq_right {b : β} {s : ∀ x : β, b = x → Set α} :
⋃ (x) (h : b = x), s x h = s b rfl :=
iSup_iSup_eq_right
#align set.Union_Union_eq_right Set.iUnion_iUnion_eq_right
theorem iInter_or {p q : Prop} (s : p ∨ q → Set α) :
⋂ h, s h = (⋂ h : p, s (Or.inl h)) ∩ ⋂ h : q, s (Or.inr h) :=
iInf_or
#align set.Inter_or Set.iInter_or
theorem iUnion_or {p q : Prop} (s : p ∨ q → Set α) :
⋃ h, s h = (⋃ i, s (Or.inl i)) ∪ ⋃ j, s (Or.inr j) :=
iSup_or
#align set.Union_or Set.iUnion_or
theorem iUnion_and {p q : Prop} (s : p ∧ q → Set α) : ⋃ h, s h = ⋃ (hp) (hq), s ⟨hp, hq⟩ :=
iSup_and
#align set.Union_and Set.iUnion_and
theorem iInter_and {p q : Prop} (s : p ∧ q → Set α) : ⋂ h, s h = ⋂ (hp) (hq), s ⟨hp, hq⟩ :=
iInf_and
#align set.Inter_and Set.iInter_and
theorem iUnion_comm (s : ι → ι' → Set α) : ⋃ (i) (i'), s i i' = ⋃ (i') (i), s i i' :=
iSup_comm
#align set.Union_comm Set.iUnion_comm
theorem iInter_comm (s : ι → ι' → Set α) : ⋂ (i) (i'), s i i' = ⋂ (i') (i), s i i' :=
iInf_comm
#align set.Inter_comm Set.iInter_comm
theorem iUnion_sigma {γ : α → Type*} (s : Sigma γ → Set β) : ⋃ ia, s ia = ⋃ i, ⋃ a, s ⟨i, a⟩ :=
iSup_sigma
theorem iUnion_sigma' {γ : α → Type*} (s : ∀ i, γ i → Set β) :
⋃ i, ⋃ a, s i a = ⋃ ia : Sigma γ, s ia.1 ia.2 :=
iSup_sigma' _
theorem iInter_sigma {γ : α → Type*} (s : Sigma γ → Set β) : ⋂ ia, s ia = ⋂ i, ⋂ a, s ⟨i, a⟩ :=
iInf_sigma
theorem iInter_sigma' {γ : α → Type*} (s : ∀ i, γ i → Set β) :
⋂ i, ⋂ a, s i a = ⋂ ia : Sigma γ, s ia.1 ia.2 :=
iInf_sigma' _
theorem iUnion₂_comm (s : ∀ i₁, κ₁ i₁ → ∀ i₂, κ₂ i₂ → Set α) :
⋃ (i₁) (j₁) (i₂) (j₂), s i₁ j₁ i₂ j₂ = ⋃ (i₂) (j₂) (i₁) (j₁), s i₁ j₁ i₂ j₂ :=
iSup₂_comm _
#align set.Union₂_comm Set.iUnion₂_comm
theorem iInter₂_comm (s : ∀ i₁, κ₁ i₁ → ∀ i₂, κ₂ i₂ → Set α) :
⋂ (i₁) (j₁) (i₂) (j₂), s i₁ j₁ i₂ j₂ = ⋂ (i₂) (j₂) (i₁) (j₁), s i₁ j₁ i₂ j₂ :=
iInf₂_comm _
#align set.Inter₂_comm Set.iInter₂_comm
@[simp]
theorem biUnion_and (p : ι → Prop) (q : ι → ι' → Prop) (s : ∀ x y, p x ∧ q x y → Set α) :
⋃ (x : ι) (y : ι') (h : p x ∧ q x y), s x y h =
⋃ (x : ι) (hx : p x) (y : ι') (hy : q x y), s x y ⟨hx, hy⟩ := by
simp only [iUnion_and, @iUnion_comm _ ι']
#align set.bUnion_and Set.biUnion_and
@[simp]
theorem biUnion_and' (p : ι' → Prop) (q : ι → ι' → Prop) (s : ∀ x y, p y ∧ q x y → Set α) :
⋃ (x : ι) (y : ι') (h : p y ∧ q x y), s x y h =
⋃ (y : ι') (hy : p y) (x : ι) (hx : q x y), s x y ⟨hy, hx⟩ := by
simp only [iUnion_and, @iUnion_comm _ ι]
#align set.bUnion_and' Set.biUnion_and'
@[simp]
theorem biInter_and (p : ι → Prop) (q : ι → ι' → Prop) (s : ∀ x y, p x ∧ q x y → Set α) :
⋂ (x : ι) (y : ι') (h : p x ∧ q x y), s x y h =
⋂ (x : ι) (hx : p x) (y : ι') (hy : q x y), s x y ⟨hx, hy⟩ := by
simp only [iInter_and, @iInter_comm _ ι']
#align set.bInter_and Set.biInter_and
@[simp]
theorem biInter_and' (p : ι' → Prop) (q : ι → ι' → Prop) (s : ∀ x y, p y ∧ q x y → Set α) :
⋂ (x : ι) (y : ι') (h : p y ∧ q x y), s x y h =
⋂ (y : ι') (hy : p y) (x : ι) (hx : q x y), s x y ⟨hy, hx⟩ := by
simp only [iInter_and, @iInter_comm _ ι]
#align set.bInter_and' Set.biInter_and'
@[simp]
theorem iUnion_iUnion_eq_or_left {b : β} {p : β → Prop} {s : ∀ x : β, x = b ∨ p x → Set α} :
⋃ (x) (h), s x h = s b (Or.inl rfl) ∪ ⋃ (x) (h : p x), s x (Or.inr h) := by
simp only [iUnion_or, iUnion_union_distrib, iUnion_iUnion_eq_left]
#align set.Union_Union_eq_or_left Set.iUnion_iUnion_eq_or_left
@[simp]
theorem iInter_iInter_eq_or_left {b : β} {p : β → Prop} {s : ∀ x : β, x = b ∨ p x → Set α} :
⋂ (x) (h), s x h = s b (Or.inl rfl) ∩ ⋂ (x) (h : p x), s x (Or.inr h) := by
simp only [iInter_or, iInter_inter_distrib, iInter_iInter_eq_left]
#align set.Inter_Inter_eq_or_left Set.iInter_iInter_eq_or_left
theorem mem_biUnion {s : Set α} {t : α → Set β} {x : α} {y : β} (xs : x ∈ s) (ytx : y ∈ t x) :
y ∈ ⋃ x ∈ s, t x :=
mem_iUnion₂_of_mem xs ytx
#align set.mem_bUnion Set.mem_biUnion
theorem mem_biInter {s : Set α} {t : α → Set β} {y : β} (h : ∀ x ∈ s, y ∈ t x) :
y ∈ ⋂ x ∈ s, t x :=
mem_iInter₂_of_mem h
#align set.mem_bInter Set.mem_biInter
theorem subset_biUnion_of_mem {s : Set α} {u : α → Set β} {x : α} (xs : x ∈ s) :
u x ⊆ ⋃ x ∈ s, u x :=
-- Porting note: Why is this not just `subset_iUnion₂ x xs`?
@subset_iUnion₂ β α (· ∈ s) (fun i _ => u i) x xs
#align set.subset_bUnion_of_mem Set.subset_biUnion_of_mem
theorem biInter_subset_of_mem {s : Set α} {t : α → Set β} {x : α} (xs : x ∈ s) :
⋂ x ∈ s, t x ⊆ t x :=
iInter₂_subset x xs
#align set.bInter_subset_of_mem Set.biInter_subset_of_mem
theorem biUnion_subset_biUnion_left {s s' : Set α} {t : α → Set β} (h : s ⊆ s') :
⋃ x ∈ s, t x ⊆ ⋃ x ∈ s', t x :=
iUnion₂_subset fun _ hx => subset_biUnion_of_mem <| h hx
#align set.bUnion_subset_bUnion_left Set.biUnion_subset_biUnion_left
theorem biInter_subset_biInter_left {s s' : Set α} {t : α → Set β} (h : s' ⊆ s) :
⋂ x ∈ s, t x ⊆ ⋂ x ∈ s', t x :=
subset_iInter₂ fun _ hx => biInter_subset_of_mem <| h hx
#align set.bInter_subset_bInter_left Set.biInter_subset_biInter_left
theorem biUnion_mono {s s' : Set α} {t t' : α → Set β} (hs : s' ⊆ s) (h : ∀ x ∈ s, t x ⊆ t' x) :
⋃ x ∈ s', t x ⊆ ⋃ x ∈ s, t' x :=
(biUnion_subset_biUnion_left hs).trans <| iUnion₂_mono h
#align set.bUnion_mono Set.biUnion_mono
theorem biInter_mono {s s' : Set α} {t t' : α → Set β} (hs : s ⊆ s') (h : ∀ x ∈ s, t x ⊆ t' x) :
⋂ x ∈ s', t x ⊆ ⋂ x ∈ s, t' x :=
(biInter_subset_biInter_left hs).trans <| iInter₂_mono h
#align set.bInter_mono Set.biInter_mono
theorem biUnion_eq_iUnion (s : Set α) (t : ∀ x ∈ s, Set β) :
⋃ x ∈ s, t x ‹_› = ⋃ x : s, t x x.2 :=
iSup_subtype'
#align set.bUnion_eq_Union Set.biUnion_eq_iUnion
theorem biInter_eq_iInter (s : Set α) (t : ∀ x ∈ s, Set β) :
⋂ x ∈ s, t x ‹_› = ⋂ x : s, t x x.2 :=
iInf_subtype'
#align set.bInter_eq_Inter Set.biInter_eq_iInter
theorem iUnion_subtype (p : α → Prop) (s : { x // p x } → Set β) :
⋃ x : { x // p x }, s x = ⋃ (x) (hx : p x), s ⟨x, hx⟩ :=
iSup_subtype
#align set.Union_subtype Set.iUnion_subtype
theorem iInter_subtype (p : α → Prop) (s : { x // p x } → Set β) :
⋂ x : { x // p x }, s x = ⋂ (x) (hx : p x), s ⟨x, hx⟩ :=
iInf_subtype
#align set.Inter_subtype Set.iInter_subtype
theorem biInter_empty (u : α → Set β) : ⋂ x ∈ (∅ : Set α), u x = univ :=
iInf_emptyset
#align set.bInter_empty Set.biInter_empty
theorem biInter_univ (u : α → Set β) : ⋂ x ∈ @univ α, u x = ⋂ x, u x :=
iInf_univ
#align set.bInter_univ Set.biInter_univ
@[simp]
theorem biUnion_self (s : Set α) : ⋃ x ∈ s, s = s :=
Subset.antisymm (iUnion₂_subset fun _ _ => Subset.refl s) fun _ hx => mem_biUnion hx hx
#align set.bUnion_self Set.biUnion_self
@[simp]
theorem iUnion_nonempty_self (s : Set α) : ⋃ _ : s.Nonempty, s = s := by
rw [iUnion_nonempty_index, biUnion_self]
#align set.Union_nonempty_self Set.iUnion_nonempty_self
theorem biInter_singleton (a : α) (s : α → Set β) : ⋂ x ∈ ({a} : Set α), s x = s a :=
iInf_singleton
#align set.bInter_singleton Set.biInter_singleton
theorem biInter_union (s t : Set α) (u : α → Set β) :
⋂ x ∈ s ∪ t, u x = (⋂ x ∈ s, u x) ∩ ⋂ x ∈ t, u x :=
iInf_union
#align set.bInter_union Set.biInter_union
theorem biInter_insert (a : α) (s : Set α) (t : α → Set β) :
⋂ x ∈ insert a s, t x = t a ∩ ⋂ x ∈ s, t x := by simp
#align set.bInter_insert Set.biInter_insert
theorem biInter_pair (a b : α) (s : α → Set β) : ⋂ x ∈ ({a, b} : Set α), s x = s a ∩ s b := by
rw [biInter_insert, biInter_singleton]
#align set.bInter_pair Set.biInter_pair
theorem biInter_inter {ι α : Type*} {s : Set ι} (hs : s.Nonempty) (f : ι → Set α) (t : Set α) :
⋂ i ∈ s, f i ∩ t = (⋂ i ∈ s, f i) ∩ t := by
haveI : Nonempty s := hs.to_subtype
simp [biInter_eq_iInter, ← iInter_inter]
#align set.bInter_inter Set.biInter_inter
theorem inter_biInter {ι α : Type*} {s : Set ι} (hs : s.Nonempty) (f : ι → Set α) (t : Set α) :
⋂ i ∈ s, t ∩ f i = t ∩ ⋂ i ∈ s, f i := by
rw [inter_comm, ← biInter_inter hs]
simp [inter_comm]
#align set.inter_bInter Set.inter_biInter
theorem biUnion_empty (s : α → Set β) : ⋃ x ∈ (∅ : Set α), s x = ∅ :=
iSup_emptyset
#align set.bUnion_empty Set.biUnion_empty
theorem biUnion_univ (s : α → Set β) : ⋃ x ∈ @univ α, s x = ⋃ x, s x :=
iSup_univ
#align set.bUnion_univ Set.biUnion_univ
theorem biUnion_singleton (a : α) (s : α → Set β) : ⋃ x ∈ ({a} : Set α), s x = s a :=
iSup_singleton
#align set.bUnion_singleton Set.biUnion_singleton
@[simp]
theorem biUnion_of_singleton (s : Set α) : ⋃ x ∈ s, {x} = s :=
ext <| by simp
#align set.bUnion_of_singleton Set.biUnion_of_singleton
theorem biUnion_union (s t : Set α) (u : α → Set β) :
⋃ x ∈ s ∪ t, u x = (⋃ x ∈ s, u x) ∪ ⋃ x ∈ t, u x :=
iSup_union
#align set.bUnion_union Set.biUnion_union
@[simp]
theorem iUnion_coe_set {α β : Type*} (s : Set α) (f : s → Set β) :
⋃ i, f i = ⋃ i ∈ s, f ⟨i, ‹i ∈ s›⟩ :=
iUnion_subtype _ _
#align set.Union_coe_set Set.iUnion_coe_set
@[simp]
theorem iInter_coe_set {α β : Type*} (s : Set α) (f : s → Set β) :
⋂ i, f i = ⋂ i ∈ s, f ⟨i, ‹i ∈ s›⟩ :=
iInter_subtype _ _
#align set.Inter_coe_set Set.iInter_coe_set
theorem biUnion_insert (a : α) (s : Set α) (t : α → Set β) :
⋃ x ∈ insert a s, t x = t a ∪ ⋃ x ∈ s, t x := by simp
#align set.bUnion_insert Set.biUnion_insert
theorem biUnion_pair (a b : α) (s : α → Set β) : ⋃ x ∈ ({a, b} : Set α), s x = s a ∪ s b := by
simp
#align set.bUnion_pair Set.biUnion_pair
theorem inter_iUnion₂ (s : Set α) (t : ∀ i, κ i → Set α) :
(s ∩ ⋃ (i) (j), t i j) = ⋃ (i) (j), s ∩ t i j := by simp only [inter_iUnion]
#align set.inter_Union₂ Set.inter_iUnion₂
theorem iUnion₂_inter (s : ∀ i, κ i → Set α) (t : Set α) :
(⋃ (i) (j), s i j) ∩ t = ⋃ (i) (j), s i j ∩ t := by simp_rw [iUnion_inter]
#align set.Union₂_inter Set.iUnion₂_inter
theorem union_iInter₂ (s : Set α) (t : ∀ i, κ i → Set α) :
(s ∪ ⋂ (i) (j), t i j) = ⋂ (i) (j), s ∪ t i j := by simp_rw [union_iInter]
#align set.union_Inter₂ Set.union_iInter₂
theorem iInter₂_union (s : ∀ i, κ i → Set α) (t : Set α) :
(⋂ (i) (j), s i j) ∪ t = ⋂ (i) (j), s i j ∪ t := by simp_rw [iInter_union]
#align set.Inter₂_union Set.iInter₂_union
theorem mem_sUnion_of_mem {x : α} {t : Set α} {S : Set (Set α)} (hx : x ∈ t) (ht : t ∈ S) :
x ∈ ⋃₀S :=
⟨t, ht, hx⟩
#align set.mem_sUnion_of_mem Set.mem_sUnion_of_mem
-- is this theorem really necessary?
theorem not_mem_of_not_mem_sUnion {x : α} {t : Set α} {S : Set (Set α)} (hx : x ∉ ⋃₀S)
(ht : t ∈ S) : x ∉ t := fun h => hx ⟨t, ht, h⟩
#align set.not_mem_of_not_mem_sUnion Set.not_mem_of_not_mem_sUnion
theorem sInter_subset_of_mem {S : Set (Set α)} {t : Set α} (tS : t ∈ S) : ⋂₀ S ⊆ t :=
sInf_le tS
#align set.sInter_subset_of_mem Set.sInter_subset_of_mem
theorem subset_sUnion_of_mem {S : Set (Set α)} {t : Set α} (tS : t ∈ S) : t ⊆ ⋃₀S :=
le_sSup tS
#align set.subset_sUnion_of_mem Set.subset_sUnion_of_mem
theorem subset_sUnion_of_subset {s : Set α} (t : Set (Set α)) (u : Set α) (h₁ : s ⊆ u)
(h₂ : u ∈ t) : s ⊆ ⋃₀t :=
Subset.trans h₁ (subset_sUnion_of_mem h₂)
#align set.subset_sUnion_of_subset Set.subset_sUnion_of_subset
theorem sUnion_subset {S : Set (Set α)} {t : Set α} (h : ∀ t' ∈ S, t' ⊆ t) : ⋃₀S ⊆ t :=
sSup_le h
#align set.sUnion_subset Set.sUnion_subset
@[simp]
theorem sUnion_subset_iff {s : Set (Set α)} {t : Set α} : ⋃₀s ⊆ t ↔ ∀ t' ∈ s, t' ⊆ t :=
sSup_le_iff
#align set.sUnion_subset_iff Set.sUnion_subset_iff
lemma sUnion_mono_subsets {s : Set (Set α)} {f : Set α → Set α} (hf : ∀ t : Set α, t ⊆ f t) :
⋃₀ s ⊆ ⋃₀ (f '' s) :=
fun _ ⟨t, htx, hxt⟩ ↦ ⟨f t, mem_image_of_mem f htx, hf t hxt⟩
lemma sUnion_mono_supsets {s : Set (Set α)} {f : Set α → Set α} (hf : ∀ t : Set α, f t ⊆ t) :
⋃₀ (f '' s) ⊆ ⋃₀ s :=
-- If t ∈ f '' s is arbitrary; t = f u for some u : Set α.
fun _ ⟨_, ⟨u, hus, hut⟩, hxt⟩ ↦ ⟨u, hus, (hut ▸ hf u) hxt⟩
theorem subset_sInter {S : Set (Set α)} {t : Set α} (h : ∀ t' ∈ S, t ⊆ t') : t ⊆ ⋂₀ S :=
le_sInf h
#align set.subset_sInter Set.subset_sInter
@[simp]
theorem subset_sInter_iff {S : Set (Set α)} {t : Set α} : t ⊆ ⋂₀ S ↔ ∀ t' ∈ S, t ⊆ t' :=
le_sInf_iff
#align set.subset_sInter_iff Set.subset_sInter_iff
@[gcongr]
theorem sUnion_subset_sUnion {S T : Set (Set α)} (h : S ⊆ T) : ⋃₀S ⊆ ⋃₀T :=
sUnion_subset fun _ hs => subset_sUnion_of_mem (h hs)
#align set.sUnion_subset_sUnion Set.sUnion_subset_sUnion
@[gcongr]
theorem sInter_subset_sInter {S T : Set (Set α)} (h : S ⊆ T) : ⋂₀ T ⊆ ⋂₀ S :=
subset_sInter fun _ hs => sInter_subset_of_mem (h hs)
#align set.sInter_subset_sInter Set.sInter_subset_sInter
@[simp]
theorem sUnion_empty : ⋃₀∅ = (∅ : Set α) :=
sSup_empty
#align set.sUnion_empty Set.sUnion_empty
@[simp]
theorem sInter_empty : ⋂₀ ∅ = (univ : Set α) :=
sInf_empty
#align set.sInter_empty Set.sInter_empty
@[simp]
theorem sUnion_singleton (s : Set α) : ⋃₀{s} = s :=
sSup_singleton
#align set.sUnion_singleton Set.sUnion_singleton
@[simp]
theorem sInter_singleton (s : Set α) : ⋂₀ {s} = s :=
sInf_singleton
#align set.sInter_singleton Set.sInter_singleton
@[simp]
theorem sUnion_eq_empty {S : Set (Set α)} : ⋃₀S = ∅ ↔ ∀ s ∈ S, s = ∅ :=
sSup_eq_bot
#align set.sUnion_eq_empty Set.sUnion_eq_empty
@[simp]
theorem sInter_eq_univ {S : Set (Set α)} : ⋂₀ S = univ ↔ ∀ s ∈ S, s = univ :=
sInf_eq_top
#align set.sInter_eq_univ Set.sInter_eq_univ
theorem subset_powerset_iff {s : Set (Set α)} {t : Set α} : s ⊆ 𝒫 t ↔ ⋃₀ s ⊆ t :=
sUnion_subset_iff.symm
theorem sUnion_powerset_gc :
GaloisConnection (⋃₀ · : Set (Set α) → Set α) (𝒫 · : Set α → Set (Set α)) :=
gc_sSup_Iic
def sUnion_powerset_gi :
GaloisInsertion (⋃₀ · : Set (Set α) → Set α) (𝒫 · : Set α → Set (Set α)) :=
gi_sSup_Iic
theorem sUnion_mem_empty_univ {S : Set (Set α)} (h : S ⊆ {∅, univ}) :
⋃₀ S ∈ ({∅, univ} : Set (Set α)) := by
simp only [mem_insert_iff, mem_singleton_iff, or_iff_not_imp_left, sUnion_eq_empty, not_forall]
rintro ⟨s, hs, hne⟩
obtain rfl : s = univ := (h hs).resolve_left hne
exact univ_subset_iff.1 <| subset_sUnion_of_mem hs
@[simp]
theorem nonempty_sUnion {S : Set (Set α)} : (⋃₀S).Nonempty ↔ ∃ s ∈ S, Set.Nonempty s := by
simp [nonempty_iff_ne_empty]
#align set.nonempty_sUnion Set.nonempty_sUnion
theorem Nonempty.of_sUnion {s : Set (Set α)} (h : (⋃₀s).Nonempty) : s.Nonempty :=
let ⟨s, hs, _⟩ := nonempty_sUnion.1 h
⟨s, hs⟩
#align set.nonempty.of_sUnion Set.Nonempty.of_sUnion
theorem Nonempty.of_sUnion_eq_univ [Nonempty α] {s : Set (Set α)} (h : ⋃₀s = univ) : s.Nonempty :=
Nonempty.of_sUnion <| h.symm ▸ univ_nonempty
#align set.nonempty.of_sUnion_eq_univ Set.Nonempty.of_sUnion_eq_univ
theorem sUnion_union (S T : Set (Set α)) : ⋃₀(S ∪ T) = ⋃₀S ∪ ⋃₀T :=
sSup_union
#align set.sUnion_union Set.sUnion_union
theorem sInter_union (S T : Set (Set α)) : ⋂₀ (S ∪ T) = ⋂₀ S ∩ ⋂₀ T :=
sInf_union
#align set.sInter_union Set.sInter_union
@[simp]
theorem sUnion_insert (s : Set α) (T : Set (Set α)) : ⋃₀insert s T = s ∪ ⋃₀T :=
sSup_insert
#align set.sUnion_insert Set.sUnion_insert
@[simp]
theorem sInter_insert (s : Set α) (T : Set (Set α)) : ⋂₀ insert s T = s ∩ ⋂₀ T :=
sInf_insert
#align set.sInter_insert Set.sInter_insert
@[simp]
theorem sUnion_diff_singleton_empty (s : Set (Set α)) : ⋃₀(s \ {∅}) = ⋃₀s :=
sSup_diff_singleton_bot s
#align set.sUnion_diff_singleton_empty Set.sUnion_diff_singleton_empty
@[simp]
theorem sInter_diff_singleton_univ (s : Set (Set α)) : ⋂₀ (s \ {univ}) = ⋂₀ s :=
sInf_diff_singleton_top s
#align set.sInter_diff_singleton_univ Set.sInter_diff_singleton_univ
theorem sUnion_pair (s t : Set α) : ⋃₀{s, t} = s ∪ t :=
sSup_pair
#align set.sUnion_pair Set.sUnion_pair
theorem sInter_pair (s t : Set α) : ⋂₀ {s, t} = s ∩ t :=
sInf_pair
#align set.sInter_pair Set.sInter_pair
@[simp]
theorem sUnion_image (f : α → Set β) (s : Set α) : ⋃₀(f '' s) = ⋃ x ∈ s, f x :=
sSup_image
#align set.sUnion_image Set.sUnion_image
@[simp]
theorem sInter_image (f : α → Set β) (s : Set α) : ⋂₀ (f '' s) = ⋂ x ∈ s, f x :=
sInf_image
#align set.sInter_image Set.sInter_image
@[simp]
theorem sUnion_range (f : ι → Set β) : ⋃₀range f = ⋃ x, f x :=
rfl
#align set.sUnion_range Set.sUnion_range
@[simp]
theorem sInter_range (f : ι → Set β) : ⋂₀ range f = ⋂ x, f x :=
rfl
#align set.sInter_range Set.sInter_range
theorem iUnion_eq_univ_iff {f : ι → Set α} : ⋃ i, f i = univ ↔ ∀ x, ∃ i, x ∈ f i := by
simp only [eq_univ_iff_forall, mem_iUnion]
#align set.Union_eq_univ_iff Set.iUnion_eq_univ_iff
theorem iUnion₂_eq_univ_iff {s : ∀ i, κ i → Set α} :
⋃ (i) (j), s i j = univ ↔ ∀ a, ∃ i j, a ∈ s i j := by
simp only [iUnion_eq_univ_iff, mem_iUnion]
#align set.Union₂_eq_univ_iff Set.iUnion₂_eq_univ_iff
theorem sUnion_eq_univ_iff {c : Set (Set α)} : ⋃₀c = univ ↔ ∀ a, ∃ b ∈ c, a ∈ b := by
simp only [eq_univ_iff_forall, mem_sUnion]
#align set.sUnion_eq_univ_iff Set.sUnion_eq_univ_iff
-- classical
theorem iInter_eq_empty_iff {f : ι → Set α} : ⋂ i, f i = ∅ ↔ ∀ x, ∃ i, x ∉ f i := by
simp [Set.eq_empty_iff_forall_not_mem]
#align set.Inter_eq_empty_iff Set.iInter_eq_empty_iff
-- classical
theorem iInter₂_eq_empty_iff {s : ∀ i, κ i → Set α} :
⋂ (i) (j), s i j = ∅ ↔ ∀ a, ∃ i j, a ∉ s i j := by
simp only [eq_empty_iff_forall_not_mem, mem_iInter, not_forall]
#align set.Inter₂_eq_empty_iff Set.iInter₂_eq_empty_iff
-- classical
theorem sInter_eq_empty_iff {c : Set (Set α)} : ⋂₀ c = ∅ ↔ ∀ a, ∃ b ∈ c, a ∉ b := by
simp [Set.eq_empty_iff_forall_not_mem]
#align set.sInter_eq_empty_iff Set.sInter_eq_empty_iff
-- classical
@[simp]
theorem nonempty_iInter {f : ι → Set α} : (⋂ i, f i).Nonempty ↔ ∃ x, ∀ i, x ∈ f i := by
simp [nonempty_iff_ne_empty, iInter_eq_empty_iff]
#align set.nonempty_Inter Set.nonempty_iInter
-- classical
-- Porting note (#10618): removing `simp`. `simp` can prove it
theorem nonempty_iInter₂ {s : ∀ i, κ i → Set α} :
(⋂ (i) (j), s i j).Nonempty ↔ ∃ a, ∀ i j, a ∈ s i j := by
simp
#align set.nonempty_Inter₂ Set.nonempty_iInter₂
-- classical
@[simp]
theorem nonempty_sInter {c : Set (Set α)} : (⋂₀ c).Nonempty ↔ ∃ a, ∀ b ∈ c, a ∈ b := by
simp [nonempty_iff_ne_empty, sInter_eq_empty_iff]
#align set.nonempty_sInter Set.nonempty_sInter
-- classical
theorem compl_sUnion (S : Set (Set α)) : (⋃₀S)ᶜ = ⋂₀ (compl '' S) :=
ext fun x => by simp
#align set.compl_sUnion Set.compl_sUnion
-- classical
theorem sUnion_eq_compl_sInter_compl (S : Set (Set α)) : ⋃₀S = (⋂₀ (compl '' S))ᶜ := by
rw [← compl_compl (⋃₀S), compl_sUnion]
#align set.sUnion_eq_compl_sInter_compl Set.sUnion_eq_compl_sInter_compl
-- classical
theorem compl_sInter (S : Set (Set α)) : (⋂₀ S)ᶜ = ⋃₀(compl '' S) := by
rw [sUnion_eq_compl_sInter_compl, compl_compl_image]
#align set.compl_sInter Set.compl_sInter
-- classical
theorem sInter_eq_compl_sUnion_compl (S : Set (Set α)) : ⋂₀ S = (⋃₀(compl '' S))ᶜ := by
rw [← compl_compl (⋂₀ S), compl_sInter]
#align set.sInter_eq_compl_sUnion_compl Set.sInter_eq_compl_sUnion_compl
theorem inter_empty_of_inter_sUnion_empty {s t : Set α} {S : Set (Set α)} (hs : t ∈ S)
(h : s ∩ ⋃₀S = ∅) : s ∩ t = ∅ :=
eq_empty_of_subset_empty <| by
rw [← h]; exact inter_subset_inter_right _ (subset_sUnion_of_mem hs)
#align set.inter_empty_of_inter_sUnion_empty Set.inter_empty_of_inter_sUnion_empty
theorem range_sigma_eq_iUnion_range {γ : α → Type*} (f : Sigma γ → β) :
range f = ⋃ a, range fun b => f ⟨a, b⟩ :=
Set.ext <| by simp
#align set.range_sigma_eq_Union_range Set.range_sigma_eq_iUnion_range
theorem iUnion_eq_range_sigma (s : α → Set β) : ⋃ i, s i = range fun a : Σi, s i => a.2 := by
simp [Set.ext_iff]
#align set.Union_eq_range_sigma Set.iUnion_eq_range_sigma
theorem iUnion_eq_range_psigma (s : ι → Set β) : ⋃ i, s i = range fun a : Σ'i, s i => a.2 := by
simp [Set.ext_iff]
#align set.Union_eq_range_psigma Set.iUnion_eq_range_psigma
theorem iUnion_image_preimage_sigma_mk_eq_self {ι : Type*} {σ : ι → Type*} (s : Set (Sigma σ)) :
⋃ i, Sigma.mk i '' (Sigma.mk i ⁻¹' s) = s := by
ext x
simp only [mem_iUnion, mem_image, mem_preimage]
constructor
· rintro ⟨i, a, h, rfl⟩
exact h
· intro h
cases' x with i a
exact ⟨i, a, h, rfl⟩
#align set.Union_image_preimage_sigma_mk_eq_self Set.iUnion_image_preimage_sigma_mk_eq_self
theorem Sigma.univ (X : α → Type*) : (Set.univ : Set (Σa, X a)) = ⋃ a, range (Sigma.mk a) :=
Set.ext fun x =>
iff_of_true trivial ⟨range (Sigma.mk x.1), Set.mem_range_self _, x.2, Sigma.eta x⟩
#align set.sigma.univ Set.Sigma.univ
alias sUnion_mono := sUnion_subset_sUnion
#align set.sUnion_mono Set.sUnion_mono
theorem iUnion_subset_iUnion_const {s : Set α} (h : ι → ι₂) : ⋃ _ : ι, s ⊆ ⋃ _ : ι₂, s :=
iSup_const_mono (α := Set α) h
#align set.Union_subset_Union_const Set.iUnion_subset_iUnion_const
@[simp]
theorem iUnion_singleton_eq_range {α β : Type*} (f : α → β) : ⋃ x : α, {f x} = range f := by
ext x
simp [@eq_comm _ x]
#align set.Union_singleton_eq_range Set.iUnion_singleton_eq_range
theorem iUnion_of_singleton (α : Type*) : (⋃ x, {x} : Set α) = univ := by simp [Set.ext_iff]
#align set.Union_of_singleton Set.iUnion_of_singleton
theorem iUnion_of_singleton_coe (s : Set α) : ⋃ i : s, ({(i : α)} : Set α) = s := by simp
#align set.Union_of_singleton_coe Set.iUnion_of_singleton_coe
theorem sUnion_eq_biUnion {s : Set (Set α)} : ⋃₀s = ⋃ (i : Set α) (_ : i ∈ s), i := by
rw [← sUnion_image, image_id']
#align set.sUnion_eq_bUnion Set.sUnion_eq_biUnion
theorem sInter_eq_biInter {s : Set (Set α)} : ⋂₀ s = ⋂ (i : Set α) (_ : i ∈ s), i := by
rw [← sInter_image, image_id']
#align set.sInter_eq_bInter Set.sInter_eq_biInter
theorem sUnion_eq_iUnion {s : Set (Set α)} : ⋃₀s = ⋃ i : s, i := by
simp only [← sUnion_range, Subtype.range_coe]
#align set.sUnion_eq_Union Set.sUnion_eq_iUnion
theorem sInter_eq_iInter {s : Set (Set α)} : ⋂₀ s = ⋂ i : s, i := by
simp only [← sInter_range, Subtype.range_coe]
#align set.sInter_eq_Inter Set.sInter_eq_iInter
@[simp]
theorem iUnion_of_empty [IsEmpty ι] (s : ι → Set α) : ⋃ i, s i = ∅ :=
iSup_of_empty _
#align set.Union_of_empty Set.iUnion_of_empty
@[simp]
theorem iInter_of_empty [IsEmpty ι] (s : ι → Set α) : ⋂ i, s i = univ :=
iInf_of_empty _
#align set.Inter_of_empty Set.iInter_of_empty
theorem union_eq_iUnion {s₁ s₂ : Set α} : s₁ ∪ s₂ = ⋃ b : Bool, cond b s₁ s₂ :=
sup_eq_iSup s₁ s₂
#align set.union_eq_Union Set.union_eq_iUnion
theorem inter_eq_iInter {s₁ s₂ : Set α} : s₁ ∩ s₂ = ⋂ b : Bool, cond b s₁ s₂ :=
inf_eq_iInf s₁ s₂
#align set.inter_eq_Inter Set.inter_eq_iInter
theorem sInter_union_sInter {S T : Set (Set α)} :
⋂₀ S ∪ ⋂₀ T = ⋂ p ∈ S ×ˢ T, (p : Set α × Set α).1 ∪ p.2 :=
sInf_sup_sInf
#align set.sInter_union_sInter Set.sInter_union_sInter
theorem sUnion_inter_sUnion {s t : Set (Set α)} :
⋃₀s ∩ ⋃₀t = ⋃ p ∈ s ×ˢ t, (p : Set α × Set α).1 ∩ p.2 :=
sSup_inf_sSup
#align set.sUnion_inter_sUnion Set.sUnion_inter_sUnion
theorem biUnion_iUnion (s : ι → Set α) (t : α → Set β) :
⋃ x ∈ ⋃ i, s i, t x = ⋃ (i) (x ∈ s i), t x := by simp [@iUnion_comm _ ι]
#align set.bUnion_Union Set.biUnion_iUnion
theorem biInter_iUnion (s : ι → Set α) (t : α → Set β) :
⋂ x ∈ ⋃ i, s i, t x = ⋂ (i) (x ∈ s i), t x := by simp [@iInter_comm _ ι]
#align set.bInter_Union Set.biInter_iUnion
theorem sUnion_iUnion (s : ι → Set (Set α)) : ⋃₀⋃ i, s i = ⋃ i, ⋃₀s i := by
simp only [sUnion_eq_biUnion, biUnion_iUnion]
#align set.sUnion_Union Set.sUnion_iUnion
theorem sInter_iUnion (s : ι → Set (Set α)) : ⋂₀ ⋃ i, s i = ⋂ i, ⋂₀ s i := by
simp only [sInter_eq_biInter, biInter_iUnion]
#align set.sInter_Union Set.sInter_iUnion
theorem iUnion_range_eq_sUnion {α β : Type*} (C : Set (Set α)) {f : ∀ s : C, β → (s : Type _)}
(hf : ∀ s : C, Surjective (f s)) : ⋃ y : β, range (fun s : C => (f s y).val) = ⋃₀C := by
ext x; constructor
· rintro ⟨s, ⟨y, rfl⟩, ⟨s, hs⟩, rfl⟩
refine ⟨_, hs, ?_⟩
exact (f ⟨s, hs⟩ y).2
· rintro ⟨s, hs, hx⟩
cases' hf ⟨s, hs⟩ ⟨x, hx⟩ with y hy
refine ⟨_, ⟨y, rfl⟩, ⟨s, hs⟩, ?_⟩
exact congr_arg Subtype.val hy
#align set.Union_range_eq_sUnion Set.iUnion_range_eq_sUnion
theorem iUnion_range_eq_iUnion (C : ι → Set α) {f : ∀ x : ι, β → C x}
(hf : ∀ x : ι, Surjective (f x)) : ⋃ y : β, range (fun x : ι => (f x y).val) = ⋃ x, C x := by
ext x; rw [mem_iUnion, mem_iUnion]; constructor
· rintro ⟨y, i, rfl⟩
exact ⟨i, (f i y).2⟩
· rintro ⟨i, hx⟩
cases' hf i ⟨x, hx⟩ with y hy
exact ⟨y, i, congr_arg Subtype.val hy⟩
#align set.Union_range_eq_Union Set.iUnion_range_eq_iUnion
theorem union_distrib_iInter_left (s : ι → Set α) (t : Set α) : (t ∪ ⋂ i, s i) = ⋂ i, t ∪ s i :=
sup_iInf_eq _ _
#align set.union_distrib_Inter_left Set.union_distrib_iInter_left
theorem union_distrib_iInter₂_left (s : Set α) (t : ∀ i, κ i → Set α) :
(s ∪ ⋂ (i) (j), t i j) = ⋂ (i) (j), s ∪ t i j := by simp_rw [union_distrib_iInter_left]
#align set.union_distrib_Inter₂_left Set.union_distrib_iInter₂_left
theorem union_distrib_iInter_right (s : ι → Set α) (t : Set α) : (⋂ i, s i) ∪ t = ⋂ i, s i ∪ t :=
iInf_sup_eq _ _
#align set.union_distrib_Inter_right Set.union_distrib_iInter_right
theorem union_distrib_iInter₂_right (s : ∀ i, κ i → Set α) (t : Set α) :
(⋂ (i) (j), s i j) ∪ t = ⋂ (i) (j), s i j ∪ t := by simp_rw [union_distrib_iInter_right]
#align set.union_distrib_Inter₂_right Set.union_distrib_iInter₂_right
section Function
@[simp]
theorem mapsTo_sUnion {S : Set (Set α)} {t : Set β} {f : α → β} :
MapsTo f (⋃₀ S) t ↔ ∀ s ∈ S, MapsTo f s t :=
sUnion_subset_iff
#align set.maps_to_sUnion Set.mapsTo_sUnion
@[simp]
theorem mapsTo_iUnion {s : ι → Set α} {t : Set β} {f : α → β} :
MapsTo f (⋃ i, s i) t ↔ ∀ i, MapsTo f (s i) t :=
iUnion_subset_iff
#align set.maps_to_Union Set.mapsTo_iUnion
theorem mapsTo_iUnion₂ {s : ∀ i, κ i → Set α} {t : Set β} {f : α → β} :
MapsTo f (⋃ (i) (j), s i j) t ↔ ∀ i j, MapsTo f (s i j) t :=
iUnion₂_subset_iff
#align set.maps_to_Union₂ Set.mapsTo_iUnion₂
theorem mapsTo_iUnion_iUnion {s : ι → Set α} {t : ι → Set β} {f : α → β}
(H : ∀ i, MapsTo f (s i) (t i)) : MapsTo f (⋃ i, s i) (⋃ i, t i) :=
mapsTo_iUnion.2 fun i ↦ (H i).mono_right (subset_iUnion t i)
#align set.maps_to_Union_Union Set.mapsTo_iUnion_iUnion
theorem mapsTo_iUnion₂_iUnion₂ {s : ∀ i, κ i → Set α} {t : ∀ i, κ i → Set β} {f : α → β}
(H : ∀ i j, MapsTo f (s i j) (t i j)) : MapsTo f (⋃ (i) (j), s i j) (⋃ (i) (j), t i j) :=
mapsTo_iUnion_iUnion fun i => mapsTo_iUnion_iUnion (H i)
#align set.maps_to_Union₂_Union₂ Set.mapsTo_iUnion₂_iUnion₂
@[simp]
theorem mapsTo_sInter {s : Set α} {T : Set (Set β)} {f : α → β} :
MapsTo f s (⋂₀ T) ↔ ∀ t ∈ T, MapsTo f s t :=
forall₂_swap
#align set.maps_to_sInter Set.mapsTo_sInter
@[simp]
theorem mapsTo_iInter {s : Set α} {t : ι → Set β} {f : α → β} :
MapsTo f s (⋂ i, t i) ↔ ∀ i, MapsTo f s (t i) :=
mapsTo_sInter.trans forall_mem_range
#align set.maps_to_Inter Set.mapsTo_iInter
theorem mapsTo_iInter₂ {s : Set α} {t : ∀ i, κ i → Set β} {f : α → β} :
MapsTo f s (⋂ (i) (j), t i j) ↔ ∀ i j, MapsTo f s (t i j) := by
simp only [mapsTo_iInter]
#align set.maps_to_Inter₂ Set.mapsTo_iInter₂
theorem mapsTo_iInter_iInter {s : ι → Set α} {t : ι → Set β} {f : α → β}
(H : ∀ i, MapsTo f (s i) (t i)) : MapsTo f (⋂ i, s i) (⋂ i, t i) :=
mapsTo_iInter.2 fun i => (H i).mono_left (iInter_subset s i)
#align set.maps_to_Inter_Inter Set.mapsTo_iInter_iInter
theorem mapsTo_iInter₂_iInter₂ {s : ∀ i, κ i → Set α} {t : ∀ i, κ i → Set β} {f : α → β}
(H : ∀ i j, MapsTo f (s i j) (t i j)) : MapsTo f (⋂ (i) (j), s i j) (⋂ (i) (j), t i j) :=
mapsTo_iInter_iInter fun i => mapsTo_iInter_iInter (H i)
#align set.maps_to_Inter₂_Inter₂ Set.mapsTo_iInter₂_iInter₂
theorem image_iInter_subset (s : ι → Set α) (f : α → β) : (f '' ⋂ i, s i) ⊆ ⋂ i, f '' s i :=
(mapsTo_iInter_iInter fun i => mapsTo_image f (s i)).image_subset
#align set.image_Inter_subset Set.image_iInter_subset
theorem image_iInter₂_subset (s : ∀ i, κ i → Set α) (f : α → β) :
(f '' ⋂ (i) (j), s i j) ⊆ ⋂ (i) (j), f '' s i j :=
(mapsTo_iInter₂_iInter₂ fun i hi => mapsTo_image f (s i hi)).image_subset
#align set.image_Inter₂_subset Set.image_iInter₂_subset
theorem image_sInter_subset (S : Set (Set α)) (f : α → β) : f '' ⋂₀ S ⊆ ⋂ s ∈ S, f '' s := by
rw [sInter_eq_biInter]
apply image_iInter₂_subset
#align set.image_sInter_subset Set.image_sInter_subset
section
open Function
variable (s : Set β) {f : α → β} {U : ι → Set β} (hU : iUnion U = univ)
theorem injective_iff_injective_of_iUnion_eq_univ :
Injective f ↔ ∀ i, Injective ((U i).restrictPreimage f) := by
refine ⟨fun H i => (U i).restrictPreimage_injective H, fun H x y e => ?_⟩
obtain ⟨i, hi⟩ := Set.mem_iUnion.mp
(show f x ∈ Set.iUnion U by rw [hU]; trivial)
injection @H i ⟨x, hi⟩ ⟨y, show f y ∈ U i from e ▸ hi⟩ (Subtype.ext e)
#align set.injective_iff_injective_of_Union_eq_univ Set.injective_iff_injective_of_iUnion_eq_univ
theorem surjective_iff_surjective_of_iUnion_eq_univ :
Surjective f ↔ ∀ i, Surjective ((U i).restrictPreimage f) := by
refine ⟨fun H i => (U i).restrictPreimage_surjective H, fun H x => ?_⟩
obtain ⟨i, hi⟩ :=
Set.mem_iUnion.mp
(show x ∈ Set.iUnion U by rw [hU]; trivial)
exact ⟨_, congr_arg Subtype.val (H i ⟨x, hi⟩).choose_spec⟩
#align set.surjective_iff_surjective_of_Union_eq_univ Set.surjective_iff_surjective_of_iUnion_eq_univ
theorem bijective_iff_bijective_of_iUnion_eq_univ :
Bijective f ↔ ∀ i, Bijective ((U i).restrictPreimage f) := by
rw [Bijective, injective_iff_injective_of_iUnion_eq_univ hU,
surjective_iff_surjective_of_iUnion_eq_univ hU]
simp [Bijective, forall_and]
#align set.bijective_iff_bijective_of_Union_eq_univ Set.bijective_iff_bijective_of_iUnion_eq_univ
end
| Mathlib/Data/Set/Lattice.lean | 1,527 | 1,539 | theorem InjOn.image_iInter_eq [Nonempty ι] {s : ι → Set α} {f : α → β} (h : InjOn f (⋃ i, s i)) :
(f '' ⋂ i, s i) = ⋂ i, f '' s i := by |
inhabit ι
refine Subset.antisymm (image_iInter_subset s f) fun y hy => ?_
simp only [mem_iInter, mem_image] at hy
choose x hx hy using hy
refine ⟨x default, mem_iInter.2 fun i => ?_, hy _⟩
suffices x default = x i by
rw [this]
apply hx
replace hx : ∀ i, x i ∈ ⋃ j, s j := fun i => (subset_iUnion _ _) (hx i)
apply h (hx _) (hx _)
simp only [hy]
|
import Mathlib.Order.Interval.Set.UnorderedInterval
import Mathlib.Algebra.Order.Interval.Set.Monoid
import Mathlib.Data.Set.Pointwise.Basic
import Mathlib.Algebra.Order.Field.Basic
import Mathlib.Algebra.Order.Group.MinMax
#align_import data.set.pointwise.interval from "leanprover-community/mathlib"@"2196ab363eb097c008d4497125e0dde23fb36db2"
open Interval Pointwise
variable {α : Type*}
namespace Set
section LinearOrderedField
variable [LinearOrderedField α] {a : α}
@[simp]
theorem preimage_mul_const_Iio (a : α) {c : α} (h : 0 < c) :
(fun x => x * c) ⁻¹' Iio a = Iio (a / c) :=
ext fun _x => (lt_div_iff h).symm
#align set.preimage_mul_const_Iio Set.preimage_mul_const_Iio
@[simp]
theorem preimage_mul_const_Ioi (a : α) {c : α} (h : 0 < c) :
(fun x => x * c) ⁻¹' Ioi a = Ioi (a / c) :=
ext fun _x => (div_lt_iff h).symm
#align set.preimage_mul_const_Ioi Set.preimage_mul_const_Ioi
@[simp]
theorem preimage_mul_const_Iic (a : α) {c : α} (h : 0 < c) :
(fun x => x * c) ⁻¹' Iic a = Iic (a / c) :=
ext fun _x => (le_div_iff h).symm
#align set.preimage_mul_const_Iic Set.preimage_mul_const_Iic
@[simp]
theorem preimage_mul_const_Ici (a : α) {c : α} (h : 0 < c) :
(fun x => x * c) ⁻¹' Ici a = Ici (a / c) :=
ext fun _x => (div_le_iff h).symm
#align set.preimage_mul_const_Ici Set.preimage_mul_const_Ici
@[simp]
theorem preimage_mul_const_Ioo (a b : α) {c : α} (h : 0 < c) :
(fun x => x * c) ⁻¹' Ioo a b = Ioo (a / c) (b / c) := by simp [← Ioi_inter_Iio, h]
#align set.preimage_mul_const_Ioo Set.preimage_mul_const_Ioo
@[simp]
theorem preimage_mul_const_Ioc (a b : α) {c : α} (h : 0 < c) :
(fun x => x * c) ⁻¹' Ioc a b = Ioc (a / c) (b / c) := by simp [← Ioi_inter_Iic, h]
#align set.preimage_mul_const_Ioc Set.preimage_mul_const_Ioc
@[simp]
theorem preimage_mul_const_Ico (a b : α) {c : α} (h : 0 < c) :
(fun x => x * c) ⁻¹' Ico a b = Ico (a / c) (b / c) := by simp [← Ici_inter_Iio, h]
#align set.preimage_mul_const_Ico Set.preimage_mul_const_Ico
@[simp]
theorem preimage_mul_const_Icc (a b : α) {c : α} (h : 0 < c) :
(fun x => x * c) ⁻¹' Icc a b = Icc (a / c) (b / c) := by simp [← Ici_inter_Iic, h]
#align set.preimage_mul_const_Icc Set.preimage_mul_const_Icc
@[simp]
theorem preimage_mul_const_Iio_of_neg (a : α) {c : α} (h : c < 0) :
(fun x => x * c) ⁻¹' Iio a = Ioi (a / c) :=
ext fun _x => (div_lt_iff_of_neg h).symm
#align set.preimage_mul_const_Iio_of_neg Set.preimage_mul_const_Iio_of_neg
@[simp]
theorem preimage_mul_const_Ioi_of_neg (a : α) {c : α} (h : c < 0) :
(fun x => x * c) ⁻¹' Ioi a = Iio (a / c) :=
ext fun _x => (lt_div_iff_of_neg h).symm
#align set.preimage_mul_const_Ioi_of_neg Set.preimage_mul_const_Ioi_of_neg
@[simp]
theorem preimage_mul_const_Iic_of_neg (a : α) {c : α} (h : c < 0) :
(fun x => x * c) ⁻¹' Iic a = Ici (a / c) :=
ext fun _x => (div_le_iff_of_neg h).symm
#align set.preimage_mul_const_Iic_of_neg Set.preimage_mul_const_Iic_of_neg
@[simp]
theorem preimage_mul_const_Ici_of_neg (a : α) {c : α} (h : c < 0) :
(fun x => x * c) ⁻¹' Ici a = Iic (a / c) :=
ext fun _x => (le_div_iff_of_neg h).symm
#align set.preimage_mul_const_Ici_of_neg Set.preimage_mul_const_Ici_of_neg
@[simp]
theorem preimage_mul_const_Ioo_of_neg (a b : α) {c : α} (h : c < 0) :
(fun x => x * c) ⁻¹' Ioo a b = Ioo (b / c) (a / c) := by simp [← Ioi_inter_Iio, h, inter_comm]
#align set.preimage_mul_const_Ioo_of_neg Set.preimage_mul_const_Ioo_of_neg
@[simp]
theorem preimage_mul_const_Ioc_of_neg (a b : α) {c : α} (h : c < 0) :
(fun x => x * c) ⁻¹' Ioc a b = Ico (b / c) (a / c) := by
simp [← Ioi_inter_Iic, ← Ici_inter_Iio, h, inter_comm]
#align set.preimage_mul_const_Ioc_of_neg Set.preimage_mul_const_Ioc_of_neg
@[simp]
theorem preimage_mul_const_Ico_of_neg (a b : α) {c : α} (h : c < 0) :
(fun x => x * c) ⁻¹' Ico a b = Ioc (b / c) (a / c) := by
simp [← Ici_inter_Iio, ← Ioi_inter_Iic, h, inter_comm]
#align set.preimage_mul_const_Ico_of_neg Set.preimage_mul_const_Ico_of_neg
@[simp]
theorem preimage_mul_const_Icc_of_neg (a b : α) {c : α} (h : c < 0) :
(fun x => x * c) ⁻¹' Icc a b = Icc (b / c) (a / c) := by simp [← Ici_inter_Iic, h, inter_comm]
#align set.preimage_mul_const_Icc_of_neg Set.preimage_mul_const_Icc_of_neg
@[simp]
theorem preimage_const_mul_Iio (a : α) {c : α} (h : 0 < c) : (c * ·) ⁻¹' Iio a = Iio (a / c) :=
ext fun _x => (lt_div_iff' h).symm
#align set.preimage_const_mul_Iio Set.preimage_const_mul_Iio
@[simp]
theorem preimage_const_mul_Ioi (a : α) {c : α} (h : 0 < c) : (c * ·) ⁻¹' Ioi a = Ioi (a / c) :=
ext fun _x => (div_lt_iff' h).symm
#align set.preimage_const_mul_Ioi Set.preimage_const_mul_Ioi
@[simp]
theorem preimage_const_mul_Iic (a : α) {c : α} (h : 0 < c) : (c * ·) ⁻¹' Iic a = Iic (a / c) :=
ext fun _x => (le_div_iff' h).symm
#align set.preimage_const_mul_Iic Set.preimage_const_mul_Iic
@[simp]
theorem preimage_const_mul_Ici (a : α) {c : α} (h : 0 < c) : (c * ·) ⁻¹' Ici a = Ici (a / c) :=
ext fun _x => (div_le_iff' h).symm
#align set.preimage_const_mul_Ici Set.preimage_const_mul_Ici
@[simp]
theorem preimage_const_mul_Ioo (a b : α) {c : α} (h : 0 < c) :
(c * ·) ⁻¹' Ioo a b = Ioo (a / c) (b / c) := by simp [← Ioi_inter_Iio, h]
#align set.preimage_const_mul_Ioo Set.preimage_const_mul_Ioo
@[simp]
theorem preimage_const_mul_Ioc (a b : α) {c : α} (h : 0 < c) :
(c * ·) ⁻¹' Ioc a b = Ioc (a / c) (b / c) := by simp [← Ioi_inter_Iic, h]
#align set.preimage_const_mul_Ioc Set.preimage_const_mul_Ioc
@[simp]
theorem preimage_const_mul_Ico (a b : α) {c : α} (h : 0 < c) :
(c * ·) ⁻¹' Ico a b = Ico (a / c) (b / c) := by simp [← Ici_inter_Iio, h]
#align set.preimage_const_mul_Ico Set.preimage_const_mul_Ico
@[simp]
theorem preimage_const_mul_Icc (a b : α) {c : α} (h : 0 < c) :
(c * ·) ⁻¹' Icc a b = Icc (a / c) (b / c) := by simp [← Ici_inter_Iic, h]
#align set.preimage_const_mul_Icc Set.preimage_const_mul_Icc
@[simp]
theorem preimage_const_mul_Iio_of_neg (a : α) {c : α} (h : c < 0) :
(c * ·) ⁻¹' Iio a = Ioi (a / c) := by
simpa only [mul_comm] using preimage_mul_const_Iio_of_neg a h
#align set.preimage_const_mul_Iio_of_neg Set.preimage_const_mul_Iio_of_neg
@[simp]
theorem preimage_const_mul_Ioi_of_neg (a : α) {c : α} (h : c < 0) :
(c * ·) ⁻¹' Ioi a = Iio (a / c) := by
simpa only [mul_comm] using preimage_mul_const_Ioi_of_neg a h
#align set.preimage_const_mul_Ioi_of_neg Set.preimage_const_mul_Ioi_of_neg
@[simp]
theorem preimage_const_mul_Iic_of_neg (a : α) {c : α} (h : c < 0) :
(c * ·) ⁻¹' Iic a = Ici (a / c) := by
simpa only [mul_comm] using preimage_mul_const_Iic_of_neg a h
#align set.preimage_const_mul_Iic_of_neg Set.preimage_const_mul_Iic_of_neg
@[simp]
theorem preimage_const_mul_Ici_of_neg (a : α) {c : α} (h : c < 0) :
(c * ·) ⁻¹' Ici a = Iic (a / c) := by
simpa only [mul_comm] using preimage_mul_const_Ici_of_neg a h
#align set.preimage_const_mul_Ici_of_neg Set.preimage_const_mul_Ici_of_neg
@[simp]
theorem preimage_const_mul_Ioo_of_neg (a b : α) {c : α} (h : c < 0) :
(c * ·) ⁻¹' Ioo a b = Ioo (b / c) (a / c) := by
simpa only [mul_comm] using preimage_mul_const_Ioo_of_neg a b h
#align set.preimage_const_mul_Ioo_of_neg Set.preimage_const_mul_Ioo_of_neg
@[simp]
theorem preimage_const_mul_Ioc_of_neg (a b : α) {c : α} (h : c < 0) :
(c * ·) ⁻¹' Ioc a b = Ico (b / c) (a / c) := by
simpa only [mul_comm] using preimage_mul_const_Ioc_of_neg a b h
#align set.preimage_const_mul_Ioc_of_neg Set.preimage_const_mul_Ioc_of_neg
@[simp]
theorem preimage_const_mul_Ico_of_neg (a b : α) {c : α} (h : c < 0) :
(c * ·) ⁻¹' Ico a b = Ioc (b / c) (a / c) := by
simpa only [mul_comm] using preimage_mul_const_Ico_of_neg a b h
#align set.preimage_const_mul_Ico_of_neg Set.preimage_const_mul_Ico_of_neg
@[simp]
theorem preimage_const_mul_Icc_of_neg (a b : α) {c : α} (h : c < 0) :
(c * ·) ⁻¹' Icc a b = Icc (b / c) (a / c) := by
simpa only [mul_comm] using preimage_mul_const_Icc_of_neg a b h
#align set.preimage_const_mul_Icc_of_neg Set.preimage_const_mul_Icc_of_neg
@[simp]
theorem preimage_mul_const_uIcc (ha : a ≠ 0) (b c : α) :
(· * a) ⁻¹' [[b, c]] = [[b / a, c / a]] :=
(lt_or_gt_of_ne ha).elim
(fun h => by
simp [← Icc_min_max, h, h.le, min_div_div_right_of_nonpos, max_div_div_right_of_nonpos])
fun ha : 0 < a => by simp [← Icc_min_max, ha, ha.le, min_div_div_right, max_div_div_right]
#align set.preimage_mul_const_uIcc Set.preimage_mul_const_uIcc
@[simp]
theorem preimage_const_mul_uIcc (ha : a ≠ 0) (b c : α) :
(a * ·) ⁻¹' [[b, c]] = [[b / a, c / a]] := by
simp only [← preimage_mul_const_uIcc ha, mul_comm]
#align set.preimage_const_mul_uIcc Set.preimage_const_mul_uIcc
@[simp]
theorem preimage_div_const_uIcc (ha : a ≠ 0) (b c : α) :
(fun x => x / a) ⁻¹' [[b, c]] = [[b * a, c * a]] := by
simp only [div_eq_mul_inv, preimage_mul_const_uIcc (inv_ne_zero ha), inv_inv]
#align set.preimage_div_const_uIcc Set.preimage_div_const_uIcc
@[simp]
theorem image_mul_const_uIcc (a b c : α) : (· * a) '' [[b, c]] = [[b * a, c * a]] :=
if ha : a = 0 then by simp [ha]
else calc
(fun x => x * a) '' [[b, c]] = (· * a⁻¹) ⁻¹' [[b, c]] :=
(Units.mk0 a ha).mulRight.image_eq_preimage _
_ = (fun x => x / a) ⁻¹' [[b, c]] := by simp only [div_eq_mul_inv]
_ = [[b * a, c * a]] := preimage_div_const_uIcc ha _ _
#align set.image_mul_const_uIcc Set.image_mul_const_uIcc
@[simp]
theorem image_const_mul_uIcc (a b c : α) : (a * ·) '' [[b, c]] = [[a * b, a * c]] := by
simpa only [mul_comm] using image_mul_const_uIcc a b c
#align set.image_const_mul_uIcc Set.image_const_mul_uIcc
@[simp]
theorem image_div_const_uIcc (a b c : α) : (fun x => x / a) '' [[b, c]] = [[b / a, c / a]] := by
simp only [div_eq_mul_inv, image_mul_const_uIcc]
#align set.image_div_const_uIcc Set.image_div_const_uIcc
theorem image_mul_right_Icc' (a b : α) {c : α} (h : 0 < c) :
(fun x => x * c) '' Icc a b = Icc (a * c) (b * c) :=
((Units.mk0 c h.ne').mulRight.image_eq_preimage _).trans (by simp [h, division_def])
#align set.image_mul_right_Icc' Set.image_mul_right_Icc'
theorem image_mul_right_Icc {a b c : α} (hab : a ≤ b) (hc : 0 ≤ c) :
(fun x => x * c) '' Icc a b = Icc (a * c) (b * c) := by
cases eq_or_lt_of_le hc
· subst c
simp [(nonempty_Icc.2 hab).image_const]
exact image_mul_right_Icc' a b ‹0 < c›
#align set.image_mul_right_Icc Set.image_mul_right_Icc
| Mathlib/Data/Set/Pointwise/Interval.lean | 826 | 828 | theorem image_mul_left_Icc' {a : α} (h : 0 < a) (b c : α) :
(a * ·) '' Icc b c = Icc (a * b) (a * c) := by |
convert image_mul_right_Icc' b c h using 1 <;> simp only [mul_comm _ a]
|
import Mathlib.Analysis.SpecialFunctions.Trigonometric.Basic
import Mathlib.Topology.Order.ProjIcc
#align_import analysis.special_functions.trigonometric.inverse from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982"
noncomputable section
open scoped Classical
open Topology Filter
open Set Filter
open Real
namespace Real
variable {x y : ℝ}
-- @[pp_nodot] Porting note: not implemented
noncomputable def arcsin : ℝ → ℝ :=
Subtype.val ∘ IccExtend (neg_le_self zero_le_one) sinOrderIso.symm
#align real.arcsin Real.arcsin
theorem arcsin_mem_Icc (x : ℝ) : arcsin x ∈ Icc (-(π / 2)) (π / 2) :=
Subtype.coe_prop _
#align real.arcsin_mem_Icc Real.arcsin_mem_Icc
@[simp]
theorem range_arcsin : range arcsin = Icc (-(π / 2)) (π / 2) := by
rw [arcsin, range_comp Subtype.val]
simp [Icc]
#align real.range_arcsin Real.range_arcsin
theorem arcsin_le_pi_div_two (x : ℝ) : arcsin x ≤ π / 2 :=
(arcsin_mem_Icc x).2
#align real.arcsin_le_pi_div_two Real.arcsin_le_pi_div_two
theorem neg_pi_div_two_le_arcsin (x : ℝ) : -(π / 2) ≤ arcsin x :=
(arcsin_mem_Icc x).1
#align real.neg_pi_div_two_le_arcsin Real.neg_pi_div_two_le_arcsin
theorem arcsin_projIcc (x : ℝ) :
arcsin (projIcc (-1) 1 (neg_le_self zero_le_one) x) = arcsin x := by
rw [arcsin, Function.comp_apply, IccExtend_val, Function.comp_apply, IccExtend,
Function.comp_apply]
#align real.arcsin_proj_Icc Real.arcsin_projIcc
theorem sin_arcsin' {x : ℝ} (hx : x ∈ Icc (-1 : ℝ) 1) : sin (arcsin x) = x := by
simpa [arcsin, IccExtend_of_mem _ _ hx, -OrderIso.apply_symm_apply] using
Subtype.ext_iff.1 (sinOrderIso.apply_symm_apply ⟨x, hx⟩)
#align real.sin_arcsin' Real.sin_arcsin'
theorem sin_arcsin {x : ℝ} (hx₁ : -1 ≤ x) (hx₂ : x ≤ 1) : sin (arcsin x) = x :=
sin_arcsin' ⟨hx₁, hx₂⟩
#align real.sin_arcsin Real.sin_arcsin
theorem arcsin_sin' {x : ℝ} (hx : x ∈ Icc (-(π / 2)) (π / 2)) : arcsin (sin x) = x :=
injOn_sin (arcsin_mem_Icc _) hx <| by rw [sin_arcsin (neg_one_le_sin _) (sin_le_one _)]
#align real.arcsin_sin' Real.arcsin_sin'
theorem arcsin_sin {x : ℝ} (hx₁ : -(π / 2) ≤ x) (hx₂ : x ≤ π / 2) : arcsin (sin x) = x :=
arcsin_sin' ⟨hx₁, hx₂⟩
#align real.arcsin_sin Real.arcsin_sin
theorem strictMonoOn_arcsin : StrictMonoOn arcsin (Icc (-1) 1) :=
(Subtype.strictMono_coe _).comp_strictMonoOn <|
sinOrderIso.symm.strictMono.strictMonoOn_IccExtend _
#align real.strict_mono_on_arcsin Real.strictMonoOn_arcsin
theorem monotone_arcsin : Monotone arcsin :=
(Subtype.mono_coe _).comp <| sinOrderIso.symm.monotone.IccExtend _
#align real.monotone_arcsin Real.monotone_arcsin
theorem injOn_arcsin : InjOn arcsin (Icc (-1) 1) :=
strictMonoOn_arcsin.injOn
#align real.inj_on_arcsin Real.injOn_arcsin
theorem arcsin_inj {x y : ℝ} (hx₁ : -1 ≤ x) (hx₂ : x ≤ 1) (hy₁ : -1 ≤ y) (hy₂ : y ≤ 1) :
arcsin x = arcsin y ↔ x = y :=
injOn_arcsin.eq_iff ⟨hx₁, hx₂⟩ ⟨hy₁, hy₂⟩
#align real.arcsin_inj Real.arcsin_inj
@[continuity]
theorem continuous_arcsin : Continuous arcsin :=
continuous_subtype_val.comp sinOrderIso.symm.continuous.Icc_extend'
#align real.continuous_arcsin Real.continuous_arcsin
theorem continuousAt_arcsin {x : ℝ} : ContinuousAt arcsin x :=
continuous_arcsin.continuousAt
#align real.continuous_at_arcsin Real.continuousAt_arcsin
theorem arcsin_eq_of_sin_eq {x y : ℝ} (h₁ : sin x = y) (h₂ : x ∈ Icc (-(π / 2)) (π / 2)) :
arcsin y = x := by
subst y
exact injOn_sin (arcsin_mem_Icc _) h₂ (sin_arcsin' (sin_mem_Icc x))
#align real.arcsin_eq_of_sin_eq Real.arcsin_eq_of_sin_eq
@[simp]
theorem arcsin_zero : arcsin 0 = 0 :=
arcsin_eq_of_sin_eq sin_zero ⟨neg_nonpos.2 pi_div_two_pos.le, pi_div_two_pos.le⟩
#align real.arcsin_zero Real.arcsin_zero
@[simp]
theorem arcsin_one : arcsin 1 = π / 2 :=
arcsin_eq_of_sin_eq sin_pi_div_two <| right_mem_Icc.2 (neg_le_self pi_div_two_pos.le)
#align real.arcsin_one Real.arcsin_one
theorem arcsin_of_one_le {x : ℝ} (hx : 1 ≤ x) : arcsin x = π / 2 := by
rw [← arcsin_projIcc, projIcc_of_right_le _ hx, Subtype.coe_mk, arcsin_one]
#align real.arcsin_of_one_le Real.arcsin_of_one_le
theorem arcsin_neg_one : arcsin (-1) = -(π / 2) :=
arcsin_eq_of_sin_eq (by rw [sin_neg, sin_pi_div_two]) <|
left_mem_Icc.2 (neg_le_self pi_div_two_pos.le)
#align real.arcsin_neg_one Real.arcsin_neg_one
theorem arcsin_of_le_neg_one {x : ℝ} (hx : x ≤ -1) : arcsin x = -(π / 2) := by
rw [← arcsin_projIcc, projIcc_of_le_left _ hx, Subtype.coe_mk, arcsin_neg_one]
#align real.arcsin_of_le_neg_one Real.arcsin_of_le_neg_one
@[simp]
theorem arcsin_neg (x : ℝ) : arcsin (-x) = -arcsin x := by
rcases le_total x (-1) with hx₁ | hx₁
· rw [arcsin_of_le_neg_one hx₁, neg_neg, arcsin_of_one_le (le_neg.2 hx₁)]
rcases le_total 1 x with hx₂ | hx₂
· rw [arcsin_of_one_le hx₂, arcsin_of_le_neg_one (neg_le_neg hx₂)]
refine arcsin_eq_of_sin_eq ?_ ?_
· rw [sin_neg, sin_arcsin hx₁ hx₂]
· exact ⟨neg_le_neg (arcsin_le_pi_div_two _), neg_le.2 (neg_pi_div_two_le_arcsin _)⟩
#align real.arcsin_neg Real.arcsin_neg
theorem arcsin_le_iff_le_sin {x y : ℝ} (hx : x ∈ Icc (-1 : ℝ) 1) (hy : y ∈ Icc (-(π / 2)) (π / 2)) :
arcsin x ≤ y ↔ x ≤ sin y := by
rw [← arcsin_sin' hy, strictMonoOn_arcsin.le_iff_le hx (sin_mem_Icc _), arcsin_sin' hy]
#align real.arcsin_le_iff_le_sin Real.arcsin_le_iff_le_sin
theorem arcsin_le_iff_le_sin' {x y : ℝ} (hy : y ∈ Ico (-(π / 2)) (π / 2)) :
arcsin x ≤ y ↔ x ≤ sin y := by
rcases le_total x (-1) with hx₁ | hx₁
· simp [arcsin_of_le_neg_one hx₁, hy.1, hx₁.trans (neg_one_le_sin _)]
cases' lt_or_le 1 x with hx₂ hx₂
· simp [arcsin_of_one_le hx₂.le, hy.2.not_le, (sin_le_one y).trans_lt hx₂]
exact arcsin_le_iff_le_sin ⟨hx₁, hx₂⟩ (mem_Icc_of_Ico hy)
#align real.arcsin_le_iff_le_sin' Real.arcsin_le_iff_le_sin'
theorem le_arcsin_iff_sin_le {x y : ℝ} (hx : x ∈ Icc (-(π / 2)) (π / 2)) (hy : y ∈ Icc (-1 : ℝ) 1) :
x ≤ arcsin y ↔ sin x ≤ y := by
rw [← neg_le_neg_iff, ← arcsin_neg,
arcsin_le_iff_le_sin ⟨neg_le_neg hy.2, neg_le.2 hy.1⟩ ⟨neg_le_neg hx.2, neg_le.2 hx.1⟩, sin_neg,
neg_le_neg_iff]
#align real.le_arcsin_iff_sin_le Real.le_arcsin_iff_sin_le
| Mathlib/Analysis/SpecialFunctions/Trigonometric/Inverse.lean | 169 | 172 | theorem le_arcsin_iff_sin_le' {x y : ℝ} (hx : x ∈ Ioc (-(π / 2)) (π / 2)) :
x ≤ arcsin y ↔ sin x ≤ y := by |
rw [← neg_le_neg_iff, ← arcsin_neg, arcsin_le_iff_le_sin' ⟨neg_le_neg hx.2, neg_lt.2 hx.1⟩,
sin_neg, neg_le_neg_iff]
|
import Mathlib.Init.Core
import Mathlib.LinearAlgebra.AffineSpace.Basis
import Mathlib.LinearAlgebra.FiniteDimensional
#align_import linear_algebra.affine_space.finite_dimensional from "leanprover-community/mathlib"@"67e606eaea14c7854bdc556bd53d98aefdf76ec0"
noncomputable section
open Affine
section AffineSpace'
variable (k : Type*) {V : Type*} {P : Type*}
variable {ι : Type*}
open AffineSubspace FiniteDimensional Module
variable [DivisionRing k] [AddCommGroup V] [Module k V] [AffineSpace V P]
theorem finiteDimensional_vectorSpan_of_finite {s : Set P} (h : Set.Finite s) :
FiniteDimensional k (vectorSpan k s) :=
span_of_finite k <| h.vsub h
#align finite_dimensional_vector_span_of_finite finiteDimensional_vectorSpan_of_finite
instance finiteDimensional_vectorSpan_range [Finite ι] (p : ι → P) :
FiniteDimensional k (vectorSpan k (Set.range p)) :=
finiteDimensional_vectorSpan_of_finite k (Set.finite_range _)
#align finite_dimensional_vector_span_range finiteDimensional_vectorSpan_range
instance finiteDimensional_vectorSpan_image_of_finite [Finite ι] (p : ι → P) (s : Set ι) :
FiniteDimensional k (vectorSpan k (p '' s)) :=
finiteDimensional_vectorSpan_of_finite k (Set.toFinite _)
#align finite_dimensional_vector_span_image_of_finite finiteDimensional_vectorSpan_image_of_finite
theorem finiteDimensional_direction_affineSpan_of_finite {s : Set P} (h : Set.Finite s) :
FiniteDimensional k (affineSpan k s).direction :=
(direction_affineSpan k s).symm ▸ finiteDimensional_vectorSpan_of_finite k h
#align finite_dimensional_direction_affine_span_of_finite finiteDimensional_direction_affineSpan_of_finite
instance finiteDimensional_direction_affineSpan_range [Finite ι] (p : ι → P) :
FiniteDimensional k (affineSpan k (Set.range p)).direction :=
finiteDimensional_direction_affineSpan_of_finite k (Set.finite_range _)
#align finite_dimensional_direction_affine_span_range finiteDimensional_direction_affineSpan_range
instance finiteDimensional_direction_affineSpan_image_of_finite [Finite ι] (p : ι → P) (s : Set ι) :
FiniteDimensional k (affineSpan k (p '' s)).direction :=
finiteDimensional_direction_affineSpan_of_finite k (Set.toFinite _)
#align finite_dimensional_direction_affine_span_image_of_finite finiteDimensional_direction_affineSpan_image_of_finite
| Mathlib/LinearAlgebra/AffineSpace/FiniteDimensional.lean | 81 | 87 | theorem finite_of_fin_dim_affineIndependent [FiniteDimensional k V] {p : ι → P}
(hi : AffineIndependent k p) : Finite ι := by |
nontriviality ι; inhabit ι
rw [affineIndependent_iff_linearIndependent_vsub k p default] at hi
letI : IsNoetherian k V := IsNoetherian.iff_fg.2 inferInstance
exact
(Set.finite_singleton default).finite_of_compl (Set.finite_coe_iff.1 hi.finite_of_isNoetherian)
|
import Mathlib.Analysis.SpecialFunctions.Trigonometric.Complex
#align_import analysis.special_functions.trigonometric.arctan from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982"
noncomputable section
namespace Real
open Set Filter
open scoped Topology Real
theorem tan_add {x y : ℝ}
(h : ((∀ k : ℤ, x ≠ (2 * k + 1) * π / 2) ∧ ∀ l : ℤ, y ≠ (2 * l + 1) * π / 2) ∨
(∃ k : ℤ, x = (2 * k + 1) * π / 2) ∧ ∃ l : ℤ, y = (2 * l + 1) * π / 2) :
tan (x + y) = (tan x + tan y) / (1 - tan x * tan y) := by
simpa only [← Complex.ofReal_inj, Complex.ofReal_sub, Complex.ofReal_add, Complex.ofReal_div,
Complex.ofReal_mul, Complex.ofReal_tan] using
@Complex.tan_add (x : ℂ) (y : ℂ) (by convert h <;> norm_cast)
#align real.tan_add Real.tan_add
theorem tan_add' {x y : ℝ}
(h : (∀ k : ℤ, x ≠ (2 * k + 1) * π / 2) ∧ ∀ l : ℤ, y ≠ (2 * l + 1) * π / 2) :
tan (x + y) = (tan x + tan y) / (1 - tan x * tan y) :=
tan_add (Or.inl h)
#align real.tan_add' Real.tan_add'
theorem tan_two_mul {x : ℝ} : tan (2 * x) = 2 * tan x / (1 - tan x ^ 2) := by
have := @Complex.tan_two_mul x
norm_cast at *
#align real.tan_two_mul Real.tan_two_mul
theorem tan_int_mul_pi_div_two (n : ℤ) : tan (n * π / 2) = 0 :=
tan_eq_zero_iff.mpr (by use n)
#align real.tan_int_mul_pi_div_two Real.tan_int_mul_pi_div_two
theorem continuousOn_tan : ContinuousOn tan {x | cos x ≠ 0} := by
suffices ContinuousOn (fun x => sin x / cos x) {x | cos x ≠ 0} by
have h_eq : (fun x => sin x / cos x) = tan := by ext1 x; rw [tan_eq_sin_div_cos]
rwa [h_eq] at this
exact continuousOn_sin.div continuousOn_cos fun x => id
#align real.continuous_on_tan Real.continuousOn_tan
@[continuity]
theorem continuous_tan : Continuous fun x : {x | cos x ≠ 0} => tan x :=
continuousOn_iff_continuous_restrict.1 continuousOn_tan
#align real.continuous_tan Real.continuous_tan
theorem continuousOn_tan_Ioo : ContinuousOn tan (Ioo (-(π / 2)) (π / 2)) := by
refine ContinuousOn.mono continuousOn_tan fun x => ?_
simp only [and_imp, mem_Ioo, mem_setOf_eq, Ne]
rw [cos_eq_zero_iff]
rintro hx_gt hx_lt ⟨r, hxr_eq⟩
rcases le_or_lt 0 r with h | h
· rw [lt_iff_not_ge] at hx_lt
refine hx_lt ?_
rw [hxr_eq, ← one_mul (π / 2), mul_div_assoc, ge_iff_le, mul_le_mul_right (half_pos pi_pos)]
simp [h]
· rw [lt_iff_not_ge] at hx_gt
refine hx_gt ?_
rw [hxr_eq, ← one_mul (π / 2), mul_div_assoc, ge_iff_le, neg_mul_eq_neg_mul,
mul_le_mul_right (half_pos pi_pos)]
have hr_le : r ≤ -1 := by rwa [Int.lt_iff_add_one_le, ← le_neg_iff_add_nonpos_right] at h
rw [← le_sub_iff_add_le, mul_comm, ← le_div_iff]
· set_option tactic.skipAssignedInstances false in norm_num
rw [← Int.cast_one, ← Int.cast_neg]; norm_cast
· exact zero_lt_two
#align real.continuous_on_tan_Ioo Real.continuousOn_tan_Ioo
theorem surjOn_tan : SurjOn tan (Ioo (-(π / 2)) (π / 2)) univ :=
have := neg_lt_self pi_div_two_pos
continuousOn_tan_Ioo.surjOn_of_tendsto (nonempty_Ioo.2 this)
(by rw [tendsto_comp_coe_Ioo_atBot this]; exact tendsto_tan_neg_pi_div_two)
(by rw [tendsto_comp_coe_Ioo_atTop this]; exact tendsto_tan_pi_div_two)
#align real.surj_on_tan Real.surjOn_tan
theorem tan_surjective : Function.Surjective tan := fun _ => surjOn_tan.subset_range trivial
#align real.tan_surjective Real.tan_surjective
theorem image_tan_Ioo : tan '' Ioo (-(π / 2)) (π / 2) = univ :=
univ_subset_iff.1 surjOn_tan
#align real.image_tan_Ioo Real.image_tan_Ioo
def tanOrderIso : Ioo (-(π / 2)) (π / 2) ≃o ℝ :=
(strictMonoOn_tan.orderIso _ _).trans <|
(OrderIso.setCongr _ _ image_tan_Ioo).trans OrderIso.Set.univ
#align real.tan_order_iso Real.tanOrderIso
-- @[pp_nodot] -- Porting note: removed
noncomputable def arctan (x : ℝ) : ℝ :=
tanOrderIso.symm x
#align real.arctan Real.arctan
@[simp]
theorem tan_arctan (x : ℝ) : tan (arctan x) = x :=
tanOrderIso.apply_symm_apply x
#align real.tan_arctan Real.tan_arctan
theorem arctan_mem_Ioo (x : ℝ) : arctan x ∈ Ioo (-(π / 2)) (π / 2) :=
Subtype.coe_prop _
#align real.arctan_mem_Ioo Real.arctan_mem_Ioo
@[simp]
theorem range_arctan : range arctan = Ioo (-(π / 2)) (π / 2) :=
((EquivLike.surjective _).range_comp _).trans Subtype.range_coe
#align real.range_arctan Real.range_arctan
theorem arctan_tan {x : ℝ} (hx₁ : -(π / 2) < x) (hx₂ : x < π / 2) : arctan (tan x) = x :=
Subtype.ext_iff.1 <| tanOrderIso.symm_apply_apply ⟨x, hx₁, hx₂⟩
#align real.arctan_tan Real.arctan_tan
theorem cos_arctan_pos (x : ℝ) : 0 < cos (arctan x) :=
cos_pos_of_mem_Ioo <| arctan_mem_Ioo x
#align real.cos_arctan_pos Real.cos_arctan_pos
theorem cos_sq_arctan (x : ℝ) : cos (arctan x) ^ 2 = 1 / (1 + x ^ 2) := by
rw_mod_cast [one_div, ← inv_one_add_tan_sq (cos_arctan_pos x).ne', tan_arctan]
#align real.cos_sq_arctan Real.cos_sq_arctan
theorem sin_arctan (x : ℝ) : sin (arctan x) = x / √(1 + x ^ 2) := by
rw_mod_cast [← tan_div_sqrt_one_add_tan_sq (cos_arctan_pos x), tan_arctan]
#align real.sin_arctan Real.sin_arctan
theorem cos_arctan (x : ℝ) : cos (arctan x) = 1 / √(1 + x ^ 2) := by
rw_mod_cast [one_div, ← inv_sqrt_one_add_tan_sq (cos_arctan_pos x), tan_arctan]
#align real.cos_arctan Real.cos_arctan
theorem arctan_lt_pi_div_two (x : ℝ) : arctan x < π / 2 :=
(arctan_mem_Ioo x).2
#align real.arctan_lt_pi_div_two Real.arctan_lt_pi_div_two
theorem neg_pi_div_two_lt_arctan (x : ℝ) : -(π / 2) < arctan x :=
(arctan_mem_Ioo x).1
#align real.neg_pi_div_two_lt_arctan Real.neg_pi_div_two_lt_arctan
theorem arctan_eq_arcsin (x : ℝ) : arctan x = arcsin (x / √(1 + x ^ 2)) :=
Eq.symm <| arcsin_eq_of_sin_eq (sin_arctan x) (mem_Icc_of_Ioo <| arctan_mem_Ioo x)
#align real.arctan_eq_arcsin Real.arctan_eq_arcsin
theorem arcsin_eq_arctan {x : ℝ} (h : x ∈ Ioo (-(1 : ℝ)) 1) :
arcsin x = arctan (x / √(1 - x ^ 2)) := by
rw_mod_cast [arctan_eq_arcsin, div_pow, sq_sqrt, one_add_div, div_div, ← sqrt_mul,
mul_div_cancel₀, sub_add_cancel, sqrt_one, div_one] <;> simp at h <;> nlinarith [h.1, h.2]
#align real.arcsin_eq_arctan Real.arcsin_eq_arctan
@[simp]
theorem arctan_zero : arctan 0 = 0 := by simp [arctan_eq_arcsin]
#align real.arctan_zero Real.arctan_zero
@[mono]
theorem arctan_strictMono : StrictMono arctan := tanOrderIso.symm.strictMono
theorem arctan_injective : arctan.Injective := arctan_strictMono.injective
@[simp]
theorem arctan_eq_zero_iff {x : ℝ} : arctan x = 0 ↔ x = 0 :=
.trans (by rw [arctan_zero]) arctan_injective.eq_iff
theorem tendsto_arctan_atTop : Tendsto arctan atTop (𝓝[<] (π / 2)) :=
tendsto_Ioo_atTop.mp tanOrderIso.symm.tendsto_atTop
theorem tendsto_arctan_atBot : Tendsto arctan atBot (𝓝[>] (-(π / 2))) :=
tendsto_Ioo_atBot.mp tanOrderIso.symm.tendsto_atBot
theorem arctan_eq_of_tan_eq {x y : ℝ} (h : tan x = y) (hx : x ∈ Ioo (-(π / 2)) (π / 2)) :
arctan y = x :=
injOn_tan (arctan_mem_Ioo _) hx (by rw [tan_arctan, h])
#align real.arctan_eq_of_tan_eq Real.arctan_eq_of_tan_eq
@[simp]
theorem arctan_one : arctan 1 = π / 4 :=
arctan_eq_of_tan_eq tan_pi_div_four <| by constructor <;> linarith [pi_pos]
#align real.arctan_one Real.arctan_one
@[simp]
theorem arctan_neg (x : ℝ) : arctan (-x) = -arctan x := by simp [arctan_eq_arcsin, neg_div]
#align real.arctan_neg Real.arctan_neg
theorem arctan_eq_arccos {x : ℝ} (h : 0 ≤ x) : arctan x = arccos (√(1 + x ^ 2))⁻¹ := by
rw [arctan_eq_arcsin, arccos_eq_arcsin]; swap; · exact inv_nonneg.2 (sqrt_nonneg _)
congr 1
rw_mod_cast [← sqrt_inv, sq_sqrt, ← one_div, one_sub_div, add_sub_cancel_left, sqrt_div,
sqrt_sq h]
all_goals positivity
#align real.arctan_eq_arccos Real.arctan_eq_arccos
-- The junk values for `arccos` and `sqrt` make this true even for `1 < x`.
theorem arccos_eq_arctan {x : ℝ} (h : 0 < x) : arccos x = arctan (√(1 - x ^ 2) / x) := by
rw [arccos, eq_comm]
refine arctan_eq_of_tan_eq ?_ ⟨?_, ?_⟩
· rw_mod_cast [tan_pi_div_two_sub, tan_arcsin, inv_div]
· linarith only [arcsin_le_pi_div_two x, pi_pos]
· linarith only [arcsin_pos.2 h]
#align real.arccos_eq_arctan Real.arccos_eq_arctan
theorem arctan_inv_of_pos {x : ℝ} (h : 0 < x) : arctan x⁻¹ = π / 2 - arctan x := by
rw [← arctan_tan (x := _ - _), tan_pi_div_two_sub, tan_arctan]
· norm_num
exact (arctan_lt_pi_div_two x).trans (half_lt_self_iff.mpr pi_pos)
· rw [sub_lt_self_iff, ← arctan_zero]
exact tanOrderIso.symm.strictMono h
theorem arctan_inv_of_neg {x : ℝ} (h : x < 0) : arctan x⁻¹ = -(π / 2) - arctan x := by
have := arctan_inv_of_pos (neg_pos.mpr h)
rwa [inv_neg, arctan_neg, neg_eq_iff_eq_neg, neg_sub', arctan_neg, neg_neg] at this
section ArctanAdd
lemma arctan_ne_mul_pi_div_two {x : ℝ} : ∀ (k : ℤ), arctan x ≠ (2 * k + 1) * π / 2 := by
by_contra!
obtain ⟨k, h⟩ := this
obtain ⟨lb, ub⟩ := arctan_mem_Ioo x
rw [h, neg_eq_neg_one_mul, mul_div_assoc, mul_lt_mul_right (by positivity)] at lb
rw [h, ← one_mul (π / 2), mul_div_assoc, mul_lt_mul_right (by positivity)] at ub
norm_cast at lb ub; change -1 < _ at lb; omega
lemma arctan_add_arctan_lt_pi_div_two {x y : ℝ} (h : x * y < 1) : arctan x + arctan y < π / 2 := by
cases' le_or_lt y 0 with hy hy
· rw [← add_zero (π / 2), ← arctan_zero]
exact add_lt_add_of_lt_of_le (arctan_lt_pi_div_two _) (tanOrderIso.symm.monotone hy)
· rw [← lt_div_iff hy, ← inv_eq_one_div] at h
replace h : arctan x < arctan y⁻¹ := tanOrderIso.symm.strictMono h
rwa [arctan_inv_of_pos hy, lt_tsub_iff_right] at h
theorem arctan_add {x y : ℝ} (h : x * y < 1) :
arctan x + arctan y = arctan ((x + y) / (1 - x * y)) := by
rw [← arctan_tan (x := _ + _)]
· congr
conv_rhs => rw [← tan_arctan x, ← tan_arctan y]
exact tan_add' ⟨arctan_ne_mul_pi_div_two, arctan_ne_mul_pi_div_two⟩
· rw [neg_lt, neg_add, ← arctan_neg, ← arctan_neg]
rw [← neg_mul_neg] at h
exact arctan_add_arctan_lt_pi_div_two h
· exact arctan_add_arctan_lt_pi_div_two h
theorem arctan_add_eq_add_pi {x y : ℝ} (h : 1 < x * y) (hx : 0 < x) :
arctan x + arctan y = arctan ((x + y) / (1 - x * y)) + π := by
have hy : 0 < y := by
have := mul_pos_iff.mp (zero_lt_one.trans h)
simpa [hx, hx.asymm]
have k := arctan_add (mul_inv x y ▸ inv_lt_one h)
rw [arctan_inv_of_pos hx, arctan_inv_of_pos hy, show _ + _ = π - (arctan x + arctan y) by ring,
sub_eq_iff_eq_add, ← sub_eq_iff_eq_add', sub_eq_add_neg, ← arctan_neg, add_comm] at k
convert k.symm using 3
field_simp
rw [show -x + -y = -(x + y) by ring, show x * y - 1 = -(1 - x * y) by ring, neg_div_neg_eq]
theorem arctan_add_eq_sub_pi {x y : ℝ} (h : 1 < x * y) (hx : x < 0) :
arctan x + arctan y = arctan ((x + y) / (1 - x * y)) - π := by
rw [← neg_mul_neg] at h
have k := arctan_add_eq_add_pi h (neg_pos.mpr hx)
rw [show _ / _ = -((x + y) / (1 - x * y)) by ring, ← neg_inj] at k
simp only [arctan_neg, neg_add, neg_neg, ← sub_eq_add_neg _ π] at k
exact k
theorem two_mul_arctan {x : ℝ} (h₁ : -1 < x) (h₂ : x < 1) :
2 * arctan x = arctan (2 * x / (1 - x ^ 2)) := by
rw [two_mul, arctan_add (by nlinarith)]; congr 1; ring
theorem two_mul_arctan_add_pi {x : ℝ} (h : 1 < x) :
2 * arctan x = arctan (2 * x / (1 - x ^ 2)) + π := by
rw [two_mul, arctan_add_eq_add_pi (by nlinarith) (by linarith)]; congr 2; ring
theorem two_mul_arctan_sub_pi {x : ℝ} (h : x < -1) :
2 * arctan x = arctan (2 * x / (1 - x ^ 2)) - π := by
rw [two_mul, arctan_add_eq_sub_pi (by nlinarith) (by linarith)]; congr 2; ring
theorem arctan_inv_2_add_arctan_inv_3 : arctan 2⁻¹ + arctan 3⁻¹ = π / 4 := by
rw [arctan_add] <;> norm_num
| Mathlib/Analysis/SpecialFunctions/Trigonometric/Arctan.lean | 293 | 294 | theorem two_mul_arctan_inv_2_sub_arctan_inv_7 : 2 * arctan 2⁻¹ - arctan 7⁻¹ = π / 4 := by |
rw [two_mul_arctan, ← arctan_one, sub_eq_iff_eq_add, arctan_add] <;> norm_num
|
import Mathlib.Data.Real.Pi.Bounds
import Mathlib.NumberTheory.NumberField.CanonicalEmbedding.ConvexBody
-- TODO. Rewrite some of the FLT results on the disciminant using the definitions and results of
-- this file
namespace NumberField
open FiniteDimensional NumberField NumberField.InfinitePlace Matrix
open scoped Classical Real nonZeroDivisors
variable (K : Type*) [Field K] [NumberField K]
noncomputable abbrev discr : ℤ := Algebra.discr ℤ (RingOfIntegers.basis K)
theorem coe_discr : (discr K : ℚ) = Algebra.discr ℚ (integralBasis K) :=
(Algebra.discr_localizationLocalization ℤ _ K (RingOfIntegers.basis K)).symm
theorem discr_ne_zero : discr K ≠ 0 := by
rw [← (Int.cast_injective (α := ℚ)).ne_iff, coe_discr]
exact Algebra.discr_not_zero_of_basis ℚ (integralBasis K)
theorem discr_eq_discr {ι : Type*} [Fintype ι] [DecidableEq ι] (b : Basis ι ℤ (𝓞 K)) :
Algebra.discr ℤ b = discr K := by
let b₀ := Basis.reindex (RingOfIntegers.basis K) (Basis.indexEquiv (RingOfIntegers.basis K) b)
rw [Algebra.discr_eq_discr (𝓞 K) b b₀, Basis.coe_reindex, Algebra.discr_reindex]
theorem discr_eq_discr_of_algEquiv {L : Type*} [Field L] [NumberField L] (f : K ≃ₐ[ℚ] L) :
discr K = discr L := by
let f₀ : 𝓞 K ≃ₗ[ℤ] 𝓞 L := (f.restrictScalars ℤ).mapIntegralClosure.toLinearEquiv
rw [← Rat.intCast_inj, coe_discr, Algebra.discr_eq_discr_of_algEquiv (integralBasis K) f,
← discr_eq_discr L ((RingOfIntegers.basis K).map f₀)]
change _ = algebraMap ℤ ℚ _
rw [← Algebra.discr_localizationLocalization ℤ (nonZeroDivisors ℤ) L]
congr
ext
simp only [Function.comp_apply, integralBasis_apply, Basis.localizationLocalization_apply,
Basis.map_apply]
rfl
open MeasureTheory MeasureTheory.Measure Zspan NumberField.mixedEmbedding
NumberField.InfinitePlace ENNReal NNReal Complex
theorem _root_.NumberField.mixedEmbedding.volume_fundamentalDomain_latticeBasis :
volume (fundamentalDomain (latticeBasis K)) =
(2 : ℝ≥0∞)⁻¹ ^ NrComplexPlaces K * sqrt ‖discr K‖₊ := by
let f : Module.Free.ChooseBasisIndex ℤ (𝓞 K) ≃ (K →+* ℂ) :=
(canonicalEmbedding.latticeBasis K).indexEquiv (Pi.basisFun ℂ _)
let e : (index K) ≃ Module.Free.ChooseBasisIndex ℤ (𝓞 K) := (indexEquiv K).trans f.symm
let M := (mixedEmbedding.stdBasis K).toMatrix ((latticeBasis K).reindex e.symm)
let N := Algebra.embeddingsMatrixReindex ℚ ℂ (integralBasis K ∘ f.symm)
RingHom.equivRatAlgHom
suffices M.map Complex.ofReal = (matrixToStdBasis K) *
(Matrix.reindex (indexEquiv K).symm (indexEquiv K).symm N).transpose by
calc volume (fundamentalDomain (latticeBasis K))
_ = ‖((mixedEmbedding.stdBasis K).toMatrix ((latticeBasis K).reindex e.symm)).det‖₊ := by
rw [← fundamentalDomain_reindex _ e.symm, ← norm_toNNReal, measure_fundamentalDomain
((latticeBasis K).reindex e.symm), volume_fundamentalDomain_stdBasis, mul_one]
rfl
_ = ‖(matrixToStdBasis K).det * N.det‖₊ := by
rw [← nnnorm_real, ← ofReal_eq_coe, RingHom.map_det, RingHom.mapMatrix_apply, this,
det_mul, det_transpose, det_reindex_self]
_ = (2 : ℝ≥0∞)⁻¹ ^ Fintype.card {w : InfinitePlace K // IsComplex w} * sqrt ‖N.det ^ 2‖₊ := by
have : ‖Complex.I‖₊ = 1 := by rw [← norm_toNNReal, norm_eq_abs, abs_I, Real.toNNReal_one]
rw [det_matrixToStdBasis, nnnorm_mul, nnnorm_pow, nnnorm_mul, this, mul_one, nnnorm_inv,
coe_mul, ENNReal.coe_pow, ← norm_toNNReal, RCLike.norm_two, Real.toNNReal_ofNat,
coe_inv two_ne_zero, coe_ofNat, nnnorm_pow, NNReal.sqrt_sq]
_ = (2 : ℝ≥0∞)⁻¹ ^ Fintype.card { w // IsComplex w } * NNReal.sqrt ‖discr K‖₊ := by
rw [← Algebra.discr_eq_det_embeddingsMatrixReindex_pow_two, Algebra.discr_reindex,
← coe_discr, map_intCast, ← Complex.nnnorm_int]
ext : 2
dsimp only [M]
rw [Matrix.map_apply, Basis.toMatrix_apply, Basis.coe_reindex, Function.comp_apply,
Equiv.symm_symm, latticeBasis_apply, ← commMap_canonical_eq_mixed, Complex.ofReal_eq_coe,
stdBasis_repr_eq_matrixToStdBasis_mul K _ (fun _ => rfl)]
rfl
theorem exists_ne_zero_mem_ideal_of_norm_le_mul_sqrt_discr (I : (FractionalIdeal (𝓞 K)⁰ K)ˣ) :
∃ a ∈ (I : FractionalIdeal (𝓞 K)⁰ K), a ≠ 0 ∧
|Algebra.norm ℚ (a:K)| ≤ FractionalIdeal.absNorm I.1 * (4 / π) ^ NrComplexPlaces K *
(finrank ℚ K).factorial / (finrank ℚ K) ^ (finrank ℚ K) * Real.sqrt |discr K| := by
-- The smallest possible value for `exists_ne_zero_mem_ideal_of_norm_le`
let B := (minkowskiBound K I * (convexBodySumFactor K)⁻¹).toReal ^ (1 / (finrank ℚ K : ℝ))
have h_le : (minkowskiBound K I) ≤ volume (convexBodySum K B) := by
refine le_of_eq ?_
rw [convexBodySum_volume, ← ENNReal.ofReal_pow (by positivity), ← Real.rpow_natCast,
← Real.rpow_mul toReal_nonneg, div_mul_cancel₀, Real.rpow_one, ofReal_toReal, mul_comm,
mul_assoc, ← coe_mul, inv_mul_cancel (convexBodySumFactor_ne_zero K), ENNReal.coe_one,
mul_one]
· exact mul_ne_top (ne_of_lt (minkowskiBound_lt_top K I)) coe_ne_top
· exact (Nat.cast_ne_zero.mpr (ne_of_gt finrank_pos))
convert exists_ne_zero_mem_ideal_of_norm_le K I h_le
rw [div_pow B, ← Real.rpow_natCast B, ← Real.rpow_mul (by positivity), div_mul_cancel₀ _
(Nat.cast_ne_zero.mpr <| ne_of_gt finrank_pos), Real.rpow_one, mul_comm_div, mul_div_assoc']
congr 1
rw [eq_comm]
calc
_ = FractionalIdeal.absNorm I.1 * (2 : ℝ)⁻¹ ^ NrComplexPlaces K * sqrt ‖discr K‖₊ *
(2 : ℝ) ^ finrank ℚ K * ((2 : ℝ) ^ NrRealPlaces K * (π / 2) ^ NrComplexPlaces K /
(Nat.factorial (finrank ℚ K)))⁻¹ := by
simp_rw [minkowskiBound, convexBodySumFactor,
volume_fundamentalDomain_fractionalIdealLatticeBasis,
volume_fundamentalDomain_latticeBasis, toReal_mul, toReal_pow, toReal_inv, coe_toReal,
toReal_ofNat, mixedEmbedding.finrank, mul_assoc]
rw [ENNReal.toReal_ofReal (Rat.cast_nonneg.mpr (FractionalIdeal.absNorm_nonneg I.1))]
simp_rw [NNReal.coe_inv, NNReal.coe_div, NNReal.coe_mul, NNReal.coe_pow, NNReal.coe_div,
coe_real_pi, NNReal.coe_ofNat, NNReal.coe_natCast]
_ = FractionalIdeal.absNorm I.1 * (2 : ℝ) ^ (finrank ℚ K - NrComplexPlaces K - NrRealPlaces K +
NrComplexPlaces K : ℤ) * Real.sqrt ‖discr K‖ * Nat.factorial (finrank ℚ K) *
π⁻¹ ^ (NrComplexPlaces K) := by
simp_rw [inv_div, div_eq_mul_inv, mul_inv, ← zpow_neg_one, ← zpow_natCast, mul_zpow,
← zpow_mul, neg_one_mul, mul_neg_one, neg_neg, Real.coe_sqrt, coe_nnnorm, sub_eq_add_neg,
zpow_add₀ (two_ne_zero : (2 : ℝ) ≠ 0)]
ring
_ = FractionalIdeal.absNorm I.1 * (2 : ℝ) ^ (2 * NrComplexPlaces K : ℤ) * Real.sqrt ‖discr K‖ *
Nat.factorial (finrank ℚ K) * π⁻¹ ^ (NrComplexPlaces K) := by
congr
rw [← card_add_two_mul_card_eq_rank, Nat.cast_add, Nat.cast_mul, Nat.cast_ofNat]
ring
_ = FractionalIdeal.absNorm I.1 * (4 / π) ^ NrComplexPlaces K * (finrank ℚ K).factorial *
Real.sqrt |discr K| := by
rw [Int.norm_eq_abs, zpow_mul, show (2 : ℝ) ^ (2 : ℤ) = 4 by norm_cast, div_pow,
inv_eq_one_div, div_pow, one_pow, zpow_natCast]
ring
| Mathlib/NumberTheory/NumberField/Discriminant.lean | 153 | 161 | theorem exists_ne_zero_mem_ringOfIntegers_of_norm_le_mul_sqrt_discr :
∃ (a : 𝓞 K), a ≠ 0 ∧
|Algebra.norm ℚ (a : K)| ≤ (4 / π) ^ NrComplexPlaces K *
(finrank ℚ K).factorial / (finrank ℚ K) ^ (finrank ℚ K) * Real.sqrt |discr K| := by |
obtain ⟨_, h_mem, h_nz, h_nm⟩ := exists_ne_zero_mem_ideal_of_norm_le_mul_sqrt_discr K ↑1
obtain ⟨a, rfl⟩ := (FractionalIdeal.mem_one_iff _).mp h_mem
refine ⟨a, ne_zero_of_map h_nz, ?_⟩
simp_rw [Units.val_one, FractionalIdeal.absNorm_one, Rat.cast_one, one_mul] at h_nm
exact h_nm
|
import Mathlib.RingTheory.EisensteinCriterion
import Mathlib.RingTheory.Polynomial.ScaleRoots
#align_import ring_theory.polynomial.eisenstein.basic from "leanprover-community/mathlib"@"2032a878972d5672e7c27c957e7a6e297b044973"
universe u v w z
variable {R : Type u}
open Ideal Algebra Finset
open Polynomial
namespace Polynomial
@[mk_iff]
structure IsWeaklyEisensteinAt [CommSemiring R] (f : R[X]) (𝓟 : Ideal R) : Prop where
mem : ∀ {n}, n < f.natDegree → f.coeff n ∈ 𝓟
#align polynomial.is_weakly_eisenstein_at Polynomial.IsWeaklyEisensteinAt
@[mk_iff]
structure IsEisensteinAt [CommSemiring R] (f : R[X]) (𝓟 : Ideal R) : Prop where
leading : f.leadingCoeff ∉ 𝓟
mem : ∀ {n}, n < f.natDegree → f.coeff n ∈ 𝓟
not_mem : f.coeff 0 ∉ 𝓟 ^ 2
#align polynomial.is_eisenstein_at Polynomial.IsEisensteinAt
namespace IsWeaklyEisensteinAt
section CommRing
variable [CommRing R] {𝓟 : Ideal R} {f : R[X]} (hf : f.IsWeaklyEisensteinAt 𝓟)
variable {S : Type v} [CommRing S] [Algebra R S]
section ScaleRoots
variable {A : Type*} [CommRing R] [CommRing A]
| Mathlib/RingTheory/Polynomial/Eisenstein/Basic.lean | 161 | 166 | theorem scaleRoots.isWeaklyEisensteinAt (p : R[X]) {x : R} {P : Ideal R} (hP : x ∈ P) :
(scaleRoots p x).IsWeaklyEisensteinAt P := by |
refine ⟨fun i => ?_⟩
rw [coeff_scaleRoots]
rw [natDegree_scaleRoots, ← tsub_pos_iff_lt] at i
exact Ideal.mul_mem_left _ _ (Ideal.pow_mem_of_mem P hP _ i)
|
import Mathlib.MeasureTheory.Measure.Typeclasses
#align_import measure_theory.measure.sub from "leanprover-community/mathlib"@"562bbf524c595c153470e53d36c57b6f891cc480"
open Set
namespace MeasureTheory
namespace Measure
noncomputable instance instSub {α : Type*} [MeasurableSpace α] : Sub (Measure α) :=
⟨fun μ ν => sInf { τ | μ ≤ τ + ν }⟩
#align measure_theory.measure.has_sub MeasureTheory.Measure.instSub
variable {α : Type*} {m : MeasurableSpace α} {μ ν : Measure α} {s : Set α}
theorem sub_def : μ - ν = sInf { d | μ ≤ d + ν } := rfl
#align measure_theory.measure.sub_def MeasureTheory.Measure.sub_def
theorem sub_le_of_le_add {d} (h : μ ≤ d + ν) : μ - ν ≤ d :=
sInf_le h
#align measure_theory.measure.sub_le_of_le_add MeasureTheory.Measure.sub_le_of_le_add
theorem sub_eq_zero_of_le (h : μ ≤ ν) : μ - ν = 0 :=
nonpos_iff_eq_zero'.1 <| sub_le_of_le_add <| by rwa [zero_add]
#align measure_theory.measure.sub_eq_zero_of_le MeasureTheory.Measure.sub_eq_zero_of_le
theorem sub_le : μ - ν ≤ μ :=
sub_le_of_le_add <| Measure.le_add_right le_rfl
#align measure_theory.measure.sub_le MeasureTheory.Measure.sub_le
@[simp]
theorem sub_top : μ - ⊤ = 0 :=
sub_eq_zero_of_le le_top
#align measure_theory.measure.sub_top MeasureTheory.Measure.sub_top
@[simp]
theorem zero_sub : 0 - μ = 0 :=
sub_eq_zero_of_le μ.zero_le
#align measure_theory.measure.zero_sub MeasureTheory.Measure.zero_sub
@[simp]
theorem sub_self : μ - μ = 0 :=
sub_eq_zero_of_le le_rfl
#align measure_theory.measure.sub_self MeasureTheory.Measure.sub_self
theorem sub_apply [IsFiniteMeasure ν] (h₁ : MeasurableSet s) (h₂ : ν ≤ μ) :
(μ - ν) s = μ s - ν s := by
-- We begin by defining `measure_sub`, which will be equal to `(μ - ν)`.
let measure_sub : Measure α := MeasureTheory.Measure.ofMeasurable
(fun (t : Set α) (_ : MeasurableSet t) => μ t - ν t) (by simp)
(fun g h_meas h_disj ↦ by
simp only [measure_iUnion h_disj h_meas]
rw [ENNReal.tsum_sub _ (h₂ <| g ·)]
rw [← measure_iUnion h_disj h_meas]
apply measure_ne_top)
-- Now, we demonstrate `μ - ν = measure_sub`, and apply it.
have h_measure_sub_add : ν + measure_sub = μ := by
ext1 t h_t_measurable_set
simp only [Pi.add_apply, coe_add]
rw [MeasureTheory.Measure.ofMeasurable_apply _ h_t_measurable_set, add_comm,
tsub_add_cancel_of_le (h₂ t)]
have h_measure_sub_eq : μ - ν = measure_sub := by
rw [MeasureTheory.Measure.sub_def]
apply le_antisymm
· apply sInf_le
simp [le_refl, add_comm, h_measure_sub_add]
apply le_sInf
intro d h_d
rw [← h_measure_sub_add, mem_setOf_eq, add_comm d] at h_d
apply Measure.le_of_add_le_add_left h_d
rw [h_measure_sub_eq]
apply Measure.ofMeasurable_apply _ h₁
#align measure_theory.measure.sub_apply MeasureTheory.Measure.sub_apply
theorem sub_add_cancel_of_le [IsFiniteMeasure ν] (h₁ : ν ≤ μ) : μ - ν + ν = μ := by
ext1 s h_s_meas
rw [add_apply, sub_apply h_s_meas h₁, tsub_add_cancel_of_le (h₁ s)]
#align measure_theory.measure.sub_add_cancel_of_le MeasureTheory.Measure.sub_add_cancel_of_le
| Mathlib/MeasureTheory/Measure/Sub.lean | 105 | 134 | theorem restrict_sub_eq_restrict_sub_restrict (h_meas_s : MeasurableSet s) :
(μ - ν).restrict s = μ.restrict s - ν.restrict s := by |
repeat rw [sub_def]
have h_nonempty : { d | μ ≤ d + ν }.Nonempty := ⟨μ, Measure.le_add_right le_rfl⟩
rw [restrict_sInf_eq_sInf_restrict h_nonempty h_meas_s]
apply le_antisymm
· refine sInf_le_sInf_of_forall_exists_le ?_
intro ν' h_ν'_in
rw [mem_setOf_eq] at h_ν'_in
refine ⟨ν'.restrict s, ?_, restrict_le_self⟩
refine ⟨ν' + (⊤ : Measure α).restrict sᶜ, ?_, ?_⟩
· rw [mem_setOf_eq, add_right_comm, Measure.le_iff]
intro t h_meas_t
repeat rw [← measure_inter_add_diff t h_meas_s]
refine add_le_add ?_ ?_
· rw [add_apply, add_apply]
apply le_add_right _
rw [← restrict_eq_self μ inter_subset_right,
← restrict_eq_self ν inter_subset_right]
apply h_ν'_in
· rw [add_apply, restrict_apply (h_meas_t.diff h_meas_s), diff_eq, inter_assoc, inter_self,
← add_apply]
have h_mu_le_add_top : μ ≤ ν' + ν + ⊤ := by simp only [add_top, le_top]
exact Measure.le_iff'.1 h_mu_le_add_top _
· ext1 t h_meas_t
simp [restrict_apply h_meas_t, restrict_apply (h_meas_t.inter h_meas_s), inter_assoc]
· refine sInf_le_sInf_of_forall_exists_le ?_
refine forall_mem_image.2 fun t h_t_in => ⟨t.restrict s, ?_, le_rfl⟩
rw [Set.mem_setOf_eq, ← restrict_add]
exact restrict_mono Subset.rfl h_t_in
|
import Mathlib.Algebra.Order.Group.OrderIso
import Mathlib.Algebra.Order.Monoid.OrderDual
import Mathlib.Data.Set.Pointwise.Basic
import Mathlib.Order.Bounds.OrderIso
import Mathlib.Order.ConditionallyCompleteLattice.Basic
#align_import algebra.bounds from "leanprover-community/mathlib"@"dd71334db81d0bd444af1ee339a29298bef40734"
open Function Set
open Pointwise
section ConditionallyCompleteLattice
section Right
variable {ι G : Type*} [Group G] [ConditionallyCompleteLattice G]
[CovariantClass G G (Function.swap (· * ·)) (· ≤ ·)] [Nonempty ι] {f : ι → G}
@[to_additive]
theorem ciSup_mul (hf : BddAbove (range f)) (a : G) : (⨆ i, f i) * a = ⨆ i, f i * a :=
(OrderIso.mulRight a).map_ciSup hf
#align csupr_mul ciSup_mul
#align csupr_add ciSup_add
@[to_additive]
theorem ciSup_div (hf : BddAbove (range f)) (a : G) : (⨆ i, f i) / a = ⨆ i, f i / a := by
simp only [div_eq_mul_inv, ciSup_mul hf]
#align csupr_div ciSup_div
#align csupr_sub ciSup_sub
@[to_additive]
theorem ciInf_mul (hf : BddBelow (range f)) (a : G) : (⨅ i, f i) * a = ⨅ i, f i * a :=
(OrderIso.mulRight a).map_ciInf hf
@[to_additive]
| Mathlib/Algebra/Bounds.lean | 185 | 186 | theorem ciInf_div (hf : BddBelow (range f)) (a : G) : (⨅ i, f i) / a = ⨅ i, f i / a := by |
simp only [div_eq_mul_inv, ciInf_mul hf]
|
import Mathlib.Algebra.BigOperators.Intervals
import Mathlib.Algebra.GeomSum
import Mathlib.Algebra.Order.Ring.Abs
import Mathlib.Data.Nat.Bitwise
import Mathlib.Data.Nat.Log
import Mathlib.Data.Nat.Prime
import Mathlib.Data.Nat.Digits
import Mathlib.RingTheory.Multiplicity
#align_import data.nat.multiplicity from "leanprover-community/mathlib"@"ceb887ddf3344dab425292e497fa2af91498437c"
open Finset Nat multiplicity
open Nat
namespace Nat
theorem multiplicity_eq_card_pow_dvd {m n b : ℕ} (hm : m ≠ 1) (hn : 0 < n) (hb : log m n < b) :
multiplicity m n = ↑((Finset.Ico 1 b).filter fun i => m ^ i ∣ n).card :=
calc
multiplicity m n = ↑(Ico 1 <| (multiplicity m n).get (finite_nat_iff.2 ⟨hm, hn⟩) + 1).card := by
simp
_ = ↑((Finset.Ico 1 b).filter fun i => m ^ i ∣ n).card :=
congr_arg _ <|
congr_arg card <|
Finset.ext fun i => by
rw [mem_filter, mem_Ico, mem_Ico, Nat.lt_succ_iff, ← @PartENat.coe_le_coe i,
PartENat.natCast_get, ← pow_dvd_iff_le_multiplicity, and_right_comm]
refine (and_iff_left_of_imp fun h => lt_of_le_of_lt ?_ hb).symm
cases' m with m
· rw [zero_pow, zero_dvd_iff] at h
exacts [(hn.ne' h.2).elim, one_le_iff_ne_zero.1 h.1]
exact le_log_of_pow_le (one_lt_iff_ne_zero_and_ne_one.2 ⟨m.succ_ne_zero, hm⟩)
(le_of_dvd hn h.2)
#align nat.multiplicity_eq_card_pow_dvd Nat.multiplicity_eq_card_pow_dvd
namespace Prime
theorem multiplicity_one {p : ℕ} (hp : p.Prime) : multiplicity p 1 = 0 :=
multiplicity.one_right hp.prime.not_unit
#align nat.prime.multiplicity_one Nat.Prime.multiplicity_one
theorem multiplicity_mul {p m n : ℕ} (hp : p.Prime) :
multiplicity p (m * n) = multiplicity p m + multiplicity p n :=
multiplicity.mul hp.prime
#align nat.prime.multiplicity_mul Nat.Prime.multiplicity_mul
theorem multiplicity_pow {p m n : ℕ} (hp : p.Prime) :
multiplicity p (m ^ n) = n • multiplicity p m :=
multiplicity.pow hp.prime
#align nat.prime.multiplicity_pow Nat.Prime.multiplicity_pow
theorem multiplicity_self {p : ℕ} (hp : p.Prime) : multiplicity p p = 1 :=
multiplicity.multiplicity_self hp.prime.not_unit hp.ne_zero
#align nat.prime.multiplicity_self Nat.Prime.multiplicity_self
theorem multiplicity_pow_self {p n : ℕ} (hp : p.Prime) : multiplicity p (p ^ n) = n :=
multiplicity.multiplicity_pow_self hp.ne_zero hp.prime.not_unit n
#align nat.prime.multiplicity_pow_self Nat.Prime.multiplicity_pow_self
theorem multiplicity_factorial {p : ℕ} (hp : p.Prime) :
∀ {n b : ℕ}, log p n < b → multiplicity p n ! = (∑ i ∈ Ico 1 b, n / p ^ i : ℕ)
| 0, b, _ => by simp [Ico, hp.multiplicity_one]
| n + 1, b, hb =>
calc
multiplicity p (n + 1)! = multiplicity p n ! + multiplicity p (n + 1) := by
rw [factorial_succ, hp.multiplicity_mul, add_comm]
_ = (∑ i ∈ Ico 1 b, n / p ^ i : ℕ) +
((Finset.Ico 1 b).filter fun i => p ^ i ∣ n + 1).card := by
rw [multiplicity_factorial hp ((log_mono_right <| le_succ _).trans_lt hb), ←
multiplicity_eq_card_pow_dvd hp.ne_one (succ_pos _) hb]
_ = (∑ i ∈ Ico 1 b, (n / p ^ i + if p ^ i ∣ n + 1 then 1 else 0) : ℕ) := by
rw [sum_add_distrib, sum_boole]
simp
_ = (∑ i ∈ Ico 1 b, (n + 1) / p ^ i : ℕ) :=
congr_arg _ <| Finset.sum_congr rfl fun _ _ => (succ_div _ _).symm
#align nat.prime.multiplicity_factorial Nat.Prime.multiplicity_factorial
theorem sub_one_mul_multiplicity_factorial {n p : ℕ} (hp : p.Prime) :
(p - 1) * (multiplicity p n !).get (finite_nat_iff.mpr ⟨hp.ne_one, factorial_pos n⟩) =
n - (p.digits n).sum := by
simp only [multiplicity_factorial hp <| lt_succ_of_lt <| lt.base (log p n),
← Finset.sum_Ico_add' _ 0 _ 1, Ico_zero_eq_range,
← sub_one_mul_sum_log_div_pow_eq_sub_sum_digits]
rfl
theorem multiplicity_factorial_mul_succ {n p : ℕ} (hp : p.Prime) :
multiplicity p (p * (n + 1))! = multiplicity p (p * n)! + multiplicity p (n + 1) + 1 := by
have hp' := hp.prime
have h0 : 2 ≤ p := hp.two_le
have h1 : 1 ≤ p * n + 1 := Nat.le_add_left _ _
have h2 : p * n + 1 ≤ p * (n + 1) := by linarith
have h3 : p * n + 1 ≤ p * (n + 1) + 1 := by omega
have hm : multiplicity p (p * n)! ≠ ⊤ := by
rw [Ne, eq_top_iff_not_finite, Classical.not_not, finite_nat_iff]
exact ⟨hp.ne_one, factorial_pos _⟩
revert hm
have h4 : ∀ m ∈ Ico (p * n + 1) (p * (n + 1)), multiplicity p m = 0 := by
intro m hm
rw [multiplicity_eq_zero, ← not_dvd_iff_between_consec_multiples _ hp.pos]
rw [mem_Ico] at hm
exact ⟨n, lt_of_succ_le hm.1, hm.2⟩
simp_rw [← prod_Ico_id_eq_factorial, multiplicity.Finset.prod hp', ← sum_Ico_consecutive _ h1 h3,
add_assoc]
intro h
rw [PartENat.add_left_cancel_iff h, sum_Ico_succ_top h2, multiplicity.mul hp',
hp.multiplicity_self, sum_congr rfl h4, sum_const_zero, zero_add, add_comm (1 : PartENat)]
#align nat.prime.multiplicity_factorial_mul_succ Nat.Prime.multiplicity_factorial_mul_succ
theorem multiplicity_factorial_mul {n p : ℕ} (hp : p.Prime) :
multiplicity p (p * n)! = multiplicity p n ! + n := by
induction' n with n ih
· simp
· simp only [succ_eq_add_one, multiplicity.mul, hp, hp.prime, ih, multiplicity_factorial_mul_succ,
← add_assoc, Nat.cast_one, Nat.cast_add, factorial_succ]
congr 1
rw [add_comm, add_assoc]
#align nat.prime.multiplicity_factorial_mul Nat.Prime.multiplicity_factorial_mul
theorem pow_dvd_factorial_iff {p : ℕ} {n r b : ℕ} (hp : p.Prime) (hbn : log p n < b) :
p ^ r ∣ n ! ↔ r ≤ ∑ i ∈ Ico 1 b, n / p ^ i := by
rw [← PartENat.coe_le_coe, ← hp.multiplicity_factorial hbn, ← pow_dvd_iff_le_multiplicity]
#align nat.prime.pow_dvd_factorial_iff Nat.Prime.pow_dvd_factorial_iff
theorem multiplicity_factorial_le_div_pred {p : ℕ} (hp : p.Prime) (n : ℕ) :
multiplicity p n ! ≤ (n / (p - 1) : ℕ) := by
rw [hp.multiplicity_factorial (lt_succ_self _), PartENat.coe_le_coe]
exact Nat.geom_sum_Ico_le hp.two_le _ _
#align nat.prime.multiplicity_factorial_le_div_pred Nat.Prime.multiplicity_factorial_le_div_pred
theorem multiplicity_choose_aux {p n b k : ℕ} (hp : p.Prime) (hkn : k ≤ n) :
∑ i ∈ Finset.Ico 1 b, n / p ^ i =
((∑ i ∈ Finset.Ico 1 b, k / p ^ i) + ∑ i ∈ Finset.Ico 1 b, (n - k) / p ^ i) +
((Finset.Ico 1 b).filter fun i => p ^ i ≤ k % p ^ i + (n - k) % p ^ i).card :=
calc
∑ i ∈ Finset.Ico 1 b, n / p ^ i = ∑ i ∈ Finset.Ico 1 b, (k + (n - k)) / p ^ i := by
simp only [add_tsub_cancel_of_le hkn]
_ = ∑ i ∈ Finset.Ico 1 b,
(k / p ^ i + (n - k) / p ^ i + if p ^ i ≤ k % p ^ i + (n - k) % p ^ i then 1 else 0) := by
simp only [Nat.add_div (pow_pos hp.pos _)]
_ = _ := by simp [sum_add_distrib, sum_boole]
#align nat.prime.multiplicity_choose_aux Nat.Prime.multiplicity_choose_aux
theorem multiplicity_choose' {p n k b : ℕ} (hp : p.Prime) (hnb : log p (n + k) < b) :
multiplicity p (choose (n + k) k) =
((Ico 1 b).filter fun i => p ^ i ≤ k % p ^ i + n % p ^ i).card := by
have h₁ :
multiplicity p (choose (n + k) k) + multiplicity p (k ! * n !) =
((Finset.Ico 1 b).filter fun i => p ^ i ≤ k % p ^ i + n % p ^ i).card +
multiplicity p (k ! * n !) := by
rw [← hp.multiplicity_mul, ← mul_assoc]
have := (add_tsub_cancel_right n k) ▸ choose_mul_factorial_mul_factorial (le_add_left k n)
rw [this, hp.multiplicity_factorial hnb, hp.multiplicity_mul,
hp.multiplicity_factorial ((log_mono_right (le_add_left k n)).trans_lt hnb),
hp.multiplicity_factorial ((log_mono_right (le_add_left n k)).trans_lt
(add_comm n k ▸ hnb)), multiplicity_choose_aux hp (le_add_left k n)]
simp [add_comm]
refine (PartENat.add_right_cancel_iff ?_).1 h₁
apply PartENat.ne_top_iff_dom.2
exact finite_nat_iff.2 ⟨hp.ne_one, mul_pos (factorial_pos k) (factorial_pos n)⟩
| Mathlib/Data/Nat/Multiplicity.lean | 222 | 228 | theorem multiplicity_choose {p n k b : ℕ} (hp : p.Prime) (hkn : k ≤ n) (hnb : log p n < b) :
multiplicity p (choose n k) =
((Ico 1 b).filter fun i => p ^ i ≤ k % p ^ i + (n - k) % p ^ i).card := by |
have := Nat.sub_add_cancel hkn
convert @multiplicity_choose' p (n - k) k b hp _
· rw [this]
exact this.symm ▸ hnb
|
import Mathlib.CategoryTheory.Subobject.MonoOver
import Mathlib.CategoryTheory.Skeletal
import Mathlib.CategoryTheory.ConcreteCategory.Basic
import Mathlib.Tactic.ApplyFun
import Mathlib.Tactic.CategoryTheory.Elementwise
#align_import category_theory.subobject.basic from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a"
universe v₁ v₂ u₁ u₂
noncomputable section
namespace CategoryTheory
open CategoryTheory CategoryTheory.Category CategoryTheory.Limits
variable {C : Type u₁} [Category.{v₁} C] {X Y Z : C}
variable {D : Type u₂} [Category.{v₂} D]
def Subobject (X : C) :=
ThinSkeleton (MonoOver X)
#align category_theory.subobject CategoryTheory.Subobject
instance (X : C) : PartialOrder (Subobject X) := by
dsimp only [Subobject]
infer_instance
open CategoryTheory.Limits
namespace Subobject
def lower {Y : D} (F : MonoOver X ⥤ MonoOver Y) : Subobject X ⥤ Subobject Y :=
ThinSkeleton.map F
#align category_theory.subobject.lower CategoryTheory.Subobject.lower
theorem lower_iso (F₁ F₂ : MonoOver X ⥤ MonoOver Y) (h : F₁ ≅ F₂) : lower F₁ = lower F₂ :=
ThinSkeleton.map_iso_eq h
#align category_theory.subobject.lower_iso CategoryTheory.Subobject.lower_iso
def lower₂ (F : MonoOver X ⥤ MonoOver Y ⥤ MonoOver Z) : Subobject X ⥤ Subobject Y ⥤ Subobject Z :=
ThinSkeleton.map₂ F
#align category_theory.subobject.lower₂ CategoryTheory.Subobject.lower₂
@[simp]
theorem lower_comm (F : MonoOver Y ⥤ MonoOver X) :
toThinSkeleton _ ⋙ lower F = F ⋙ toThinSkeleton _ :=
rfl
#align category_theory.subobject.lower_comm CategoryTheory.Subobject.lower_comm
def lowerAdjunction {A : C} {B : D} {L : MonoOver A ⥤ MonoOver B} {R : MonoOver B ⥤ MonoOver A}
(h : L ⊣ R) : lower L ⊣ lower R :=
ThinSkeleton.lowerAdjunction _ _ h
#align category_theory.subobject.lower_adjunction CategoryTheory.Subobject.lowerAdjunction
@[simps]
def lowerEquivalence {A : C} {B : D} (e : MonoOver A ≌ MonoOver B) : Subobject A ≌ Subobject B where
functor := lower e.functor
inverse := lower e.inverse
unitIso := by
apply eqToIso
convert ThinSkeleton.map_iso_eq e.unitIso
· exact ThinSkeleton.map_id_eq.symm
· exact (ThinSkeleton.map_comp_eq _ _).symm
counitIso := by
apply eqToIso
convert ThinSkeleton.map_iso_eq e.counitIso
· exact (ThinSkeleton.map_comp_eq _ _).symm
· exact ThinSkeleton.map_id_eq.symm
#align category_theory.subobject.lower_equivalence CategoryTheory.Subobject.lowerEquivalence
section Map
def map (f : X ⟶ Y) [Mono f] : Subobject X ⥤ Subobject Y :=
lower (MonoOver.map f)
#align category_theory.subobject.map CategoryTheory.Subobject.map
| Mathlib/CategoryTheory/Subobject/Basic.lean | 580 | 582 | theorem map_id (x : Subobject X) : (map (𝟙 X)).obj x = x := by |
induction' x using Quotient.inductionOn' with f
exact Quotient.sound ⟨(MonoOver.mapId _).app f⟩
|
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
| Mathlib/RingTheory/MvPolynomial/WeightedHomogeneous.lean | 89 | 91 | theorem weightedTotalDegree'_zero (w : σ → M) :
weightedTotalDegree' w (0 : MvPolynomial σ R) = ⊥ := by |
simp only [weightedTotalDegree', support_zero, Finset.sup_empty]
|
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
| Mathlib/MeasureTheory/Constructions/Cylinders.lean | 205 | 207 | 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
|
import Mathlib.Analysis.SpecialFunctions.Trigonometric.Basic
import Mathlib.Analysis.Normed.Group.AddCircle
import Mathlib.Algebra.CharZero.Quotient
import Mathlib.Topology.Instances.Sign
#align_import analysis.special_functions.trigonometric.angle from "leanprover-community/mathlib"@"213b0cff7bc5ab6696ee07cceec80829ce42efec"
open Real
noncomputable section
namespace Real
-- Porting note: can't derive `NormedAddCommGroup, Inhabited`
def Angle : Type :=
AddCircle (2 * π)
#align real.angle Real.Angle
namespace Angle
-- Porting note (#10754): added due to missing instances due to no deriving
instance : NormedAddCommGroup Angle :=
inferInstanceAs (NormedAddCommGroup (AddCircle (2 * π)))
-- Porting note (#10754): added due to missing instances due to no deriving
instance : Inhabited Angle :=
inferInstanceAs (Inhabited (AddCircle (2 * π)))
-- Porting note (#10754): added due to missing instances due to no deriving
-- also, without this, a plain `QuotientAddGroup.mk`
-- causes coerced terms to be of type `ℝ ⧸ AddSubgroup.zmultiples (2 * π)`
@[coe]
protected def coe (r : ℝ) : Angle := QuotientAddGroup.mk r
instance : Coe ℝ Angle := ⟨Angle.coe⟩
instance : CircularOrder Real.Angle :=
QuotientAddGroup.circularOrder (hp' := ⟨by norm_num [pi_pos]⟩)
@[continuity]
theorem continuous_coe : Continuous ((↑) : ℝ → Angle) :=
continuous_quotient_mk'
#align real.angle.continuous_coe Real.Angle.continuous_coe
def coeHom : ℝ →+ Angle :=
QuotientAddGroup.mk' _
#align real.angle.coe_hom Real.Angle.coeHom
@[simp]
theorem coe_coeHom : (coeHom : ℝ → Angle) = ((↑) : ℝ → Angle) :=
rfl
#align real.angle.coe_coe_hom Real.Angle.coe_coeHom
@[elab_as_elim]
protected theorem induction_on {p : Angle → Prop} (θ : Angle) (h : ∀ x : ℝ, p x) : p θ :=
Quotient.inductionOn' θ h
#align real.angle.induction_on Real.Angle.induction_on
@[simp]
theorem coe_zero : ↑(0 : ℝ) = (0 : Angle) :=
rfl
#align real.angle.coe_zero Real.Angle.coe_zero
@[simp]
theorem coe_add (x y : ℝ) : ↑(x + y : ℝ) = (↑x + ↑y : Angle) :=
rfl
#align real.angle.coe_add Real.Angle.coe_add
@[simp]
theorem coe_neg (x : ℝ) : ↑(-x : ℝ) = -(↑x : Angle) :=
rfl
#align real.angle.coe_neg Real.Angle.coe_neg
@[simp]
theorem coe_sub (x y : ℝ) : ↑(x - y : ℝ) = (↑x - ↑y : Angle) :=
rfl
#align real.angle.coe_sub Real.Angle.coe_sub
theorem coe_nsmul (n : ℕ) (x : ℝ) : ↑(n • x : ℝ) = n • (↑x : Angle) :=
rfl
#align real.angle.coe_nsmul Real.Angle.coe_nsmul
theorem coe_zsmul (z : ℤ) (x : ℝ) : ↑(z • x : ℝ) = z • (↑x : Angle) :=
rfl
#align real.angle.coe_zsmul Real.Angle.coe_zsmul
@[simp, norm_cast]
theorem natCast_mul_eq_nsmul (x : ℝ) (n : ℕ) : ↑((n : ℝ) * x) = n • (↑x : Angle) := by
simpa only [nsmul_eq_mul] using coeHom.map_nsmul x n
#align real.angle.coe_nat_mul_eq_nsmul Real.Angle.natCast_mul_eq_nsmul
@[simp, norm_cast]
theorem intCast_mul_eq_zsmul (x : ℝ) (n : ℤ) : ↑((n : ℝ) * x : ℝ) = n • (↑x : Angle) := by
simpa only [zsmul_eq_mul] using coeHom.map_zsmul x n
#align real.angle.coe_int_mul_eq_zsmul Real.Angle.intCast_mul_eq_zsmul
@[deprecated (since := "2024-05-25")] alias coe_nat_mul_eq_nsmul := natCast_mul_eq_nsmul
@[deprecated (since := "2024-05-25")] alias coe_int_mul_eq_zsmul := intCast_mul_eq_zsmul
theorem angle_eq_iff_two_pi_dvd_sub {ψ θ : ℝ} : (θ : Angle) = ψ ↔ ∃ k : ℤ, θ - ψ = 2 * π * k := by
simp only [QuotientAddGroup.eq, AddSubgroup.zmultiples_eq_closure,
AddSubgroup.mem_closure_singleton, zsmul_eq_mul', (sub_eq_neg_add _ _).symm, eq_comm]
-- Porting note: added `rw`, `simp [Angle.coe, QuotientAddGroup.eq]` doesn't fire otherwise
rw [Angle.coe, Angle.coe, QuotientAddGroup.eq]
simp only [AddSubgroup.zmultiples_eq_closure,
AddSubgroup.mem_closure_singleton, zsmul_eq_mul', (sub_eq_neg_add _ _).symm, eq_comm]
#align real.angle.angle_eq_iff_two_pi_dvd_sub Real.Angle.angle_eq_iff_two_pi_dvd_sub
@[simp]
theorem coe_two_pi : ↑(2 * π : ℝ) = (0 : Angle) :=
angle_eq_iff_two_pi_dvd_sub.2 ⟨1, by rw [sub_zero, Int.cast_one, mul_one]⟩
#align real.angle.coe_two_pi Real.Angle.coe_two_pi
@[simp]
theorem neg_coe_pi : -(π : Angle) = π := by
rw [← coe_neg, angle_eq_iff_two_pi_dvd_sub]
use -1
simp [two_mul, sub_eq_add_neg]
#align real.angle.neg_coe_pi Real.Angle.neg_coe_pi
@[simp]
theorem two_nsmul_coe_div_two (θ : ℝ) : (2 : ℕ) • (↑(θ / 2) : Angle) = θ := by
rw [← coe_nsmul, two_nsmul, add_halves]
#align real.angle.two_nsmul_coe_div_two Real.Angle.two_nsmul_coe_div_two
@[simp]
theorem two_zsmul_coe_div_two (θ : ℝ) : (2 : ℤ) • (↑(θ / 2) : Angle) = θ := by
rw [← coe_zsmul, two_zsmul, add_halves]
#align real.angle.two_zsmul_coe_div_two Real.Angle.two_zsmul_coe_div_two
-- Porting note (#10618): @[simp] can prove it
theorem two_nsmul_neg_pi_div_two : (2 : ℕ) • (↑(-π / 2) : Angle) = π := by
rw [two_nsmul_coe_div_two, coe_neg, neg_coe_pi]
#align real.angle.two_nsmul_neg_pi_div_two Real.Angle.two_nsmul_neg_pi_div_two
-- Porting note (#10618): @[simp] can prove it
theorem two_zsmul_neg_pi_div_two : (2 : ℤ) • (↑(-π / 2) : Angle) = π := by
rw [two_zsmul, ← two_nsmul, two_nsmul_neg_pi_div_two]
#align real.angle.two_zsmul_neg_pi_div_two Real.Angle.two_zsmul_neg_pi_div_two
theorem sub_coe_pi_eq_add_coe_pi (θ : Angle) : θ - π = θ + π := by
rw [sub_eq_add_neg, neg_coe_pi]
#align real.angle.sub_coe_pi_eq_add_coe_pi Real.Angle.sub_coe_pi_eq_add_coe_pi
@[simp]
theorem two_nsmul_coe_pi : (2 : ℕ) • (π : Angle) = 0 := by simp [← natCast_mul_eq_nsmul]
#align real.angle.two_nsmul_coe_pi Real.Angle.two_nsmul_coe_pi
@[simp]
theorem two_zsmul_coe_pi : (2 : ℤ) • (π : Angle) = 0 := by simp [← intCast_mul_eq_zsmul]
#align real.angle.two_zsmul_coe_pi Real.Angle.two_zsmul_coe_pi
@[simp]
theorem coe_pi_add_coe_pi : (π : Real.Angle) + π = 0 := by rw [← two_nsmul, two_nsmul_coe_pi]
#align real.angle.coe_pi_add_coe_pi Real.Angle.coe_pi_add_coe_pi
theorem zsmul_eq_iff {ψ θ : Angle} {z : ℤ} (hz : z ≠ 0) :
z • ψ = z • θ ↔ ∃ k : Fin z.natAbs, ψ = θ + (k : ℕ) • (2 * π / z : ℝ) :=
QuotientAddGroup.zmultiples_zsmul_eq_zsmul_iff hz
#align real.angle.zsmul_eq_iff Real.Angle.zsmul_eq_iff
theorem nsmul_eq_iff {ψ θ : Angle} {n : ℕ} (hz : n ≠ 0) :
n • ψ = n • θ ↔ ∃ k : Fin n, ψ = θ + (k : ℕ) • (2 * π / n : ℝ) :=
QuotientAddGroup.zmultiples_nsmul_eq_nsmul_iff hz
#align real.angle.nsmul_eq_iff Real.Angle.nsmul_eq_iff
theorem two_zsmul_eq_iff {ψ θ : Angle} : (2 : ℤ) • ψ = (2 : ℤ) • θ ↔ ψ = θ ∨ ψ = θ + ↑π := by
-- Porting note: no `Int.natAbs_bit0` anymore
have : Int.natAbs 2 = 2 := rfl
rw [zsmul_eq_iff two_ne_zero, this, Fin.exists_fin_two, Fin.val_zero,
Fin.val_one, zero_smul, add_zero, one_smul, Int.cast_two,
mul_div_cancel_left₀ (_ : ℝ) two_ne_zero]
#align real.angle.two_zsmul_eq_iff Real.Angle.two_zsmul_eq_iff
theorem two_nsmul_eq_iff {ψ θ : Angle} : (2 : ℕ) • ψ = (2 : ℕ) • θ ↔ ψ = θ ∨ ψ = θ + ↑π := by
simp_rw [← natCast_zsmul, Nat.cast_ofNat, two_zsmul_eq_iff]
#align real.angle.two_nsmul_eq_iff Real.Angle.two_nsmul_eq_iff
theorem two_nsmul_eq_zero_iff {θ : Angle} : (2 : ℕ) • θ = 0 ↔ θ = 0 ∨ θ = π := by
convert two_nsmul_eq_iff <;> simp
#align real.angle.two_nsmul_eq_zero_iff Real.Angle.two_nsmul_eq_zero_iff
theorem two_nsmul_ne_zero_iff {θ : Angle} : (2 : ℕ) • θ ≠ 0 ↔ θ ≠ 0 ∧ θ ≠ π := by
rw [← not_or, ← two_nsmul_eq_zero_iff]
#align real.angle.two_nsmul_ne_zero_iff Real.Angle.two_nsmul_ne_zero_iff
theorem two_zsmul_eq_zero_iff {θ : Angle} : (2 : ℤ) • θ = 0 ↔ θ = 0 ∨ θ = π := by
simp_rw [two_zsmul, ← two_nsmul, two_nsmul_eq_zero_iff]
#align real.angle.two_zsmul_eq_zero_iff Real.Angle.two_zsmul_eq_zero_iff
theorem two_zsmul_ne_zero_iff {θ : Angle} : (2 : ℤ) • θ ≠ 0 ↔ θ ≠ 0 ∧ θ ≠ π := by
rw [← not_or, ← two_zsmul_eq_zero_iff]
#align real.angle.two_zsmul_ne_zero_iff Real.Angle.two_zsmul_ne_zero_iff
theorem eq_neg_self_iff {θ : Angle} : θ = -θ ↔ θ = 0 ∨ θ = π := by
rw [← add_eq_zero_iff_eq_neg, ← two_nsmul, two_nsmul_eq_zero_iff]
#align real.angle.eq_neg_self_iff Real.Angle.eq_neg_self_iff
theorem ne_neg_self_iff {θ : Angle} : θ ≠ -θ ↔ θ ≠ 0 ∧ θ ≠ π := by
rw [← not_or, ← eq_neg_self_iff.not]
#align real.angle.ne_neg_self_iff Real.Angle.ne_neg_self_iff
theorem neg_eq_self_iff {θ : Angle} : -θ = θ ↔ θ = 0 ∨ θ = π := by rw [eq_comm, eq_neg_self_iff]
#align real.angle.neg_eq_self_iff Real.Angle.neg_eq_self_iff
theorem neg_ne_self_iff {θ : Angle} : -θ ≠ θ ↔ θ ≠ 0 ∧ θ ≠ π := by
rw [← not_or, ← neg_eq_self_iff.not]
#align real.angle.neg_ne_self_iff Real.Angle.neg_ne_self_iff
theorem two_nsmul_eq_pi_iff {θ : Angle} : (2 : ℕ) • θ = π ↔ θ = (π / 2 : ℝ) ∨ θ = (-π / 2 : ℝ) := by
have h : (π : Angle) = ((2 : ℕ) • (π / 2 : ℝ) :) := by rw [two_nsmul, add_halves]
nth_rw 1 [h]
rw [coe_nsmul, two_nsmul_eq_iff]
-- Porting note: `congr` didn't simplify the goal of iff of `Or`s
convert Iff.rfl
rw [add_comm, ← coe_add, ← sub_eq_zero, ← coe_sub, neg_div, ← neg_sub, sub_neg_eq_add, add_assoc,
add_halves, ← two_mul, coe_neg, coe_two_pi, neg_zero]
#align real.angle.two_nsmul_eq_pi_iff Real.Angle.two_nsmul_eq_pi_iff
theorem two_zsmul_eq_pi_iff {θ : Angle} : (2 : ℤ) • θ = π ↔ θ = (π / 2 : ℝ) ∨ θ = (-π / 2 : ℝ) := by
rw [two_zsmul, ← two_nsmul, two_nsmul_eq_pi_iff]
#align real.angle.two_zsmul_eq_pi_iff Real.Angle.two_zsmul_eq_pi_iff
theorem cos_eq_iff_coe_eq_or_eq_neg {θ ψ : ℝ} :
cos θ = cos ψ ↔ (θ : Angle) = ψ ∨ (θ : Angle) = -ψ := by
constructor
· intro Hcos
rw [← sub_eq_zero, cos_sub_cos, mul_eq_zero, mul_eq_zero, neg_eq_zero,
eq_false (two_ne_zero' ℝ), false_or_iff, sin_eq_zero_iff, sin_eq_zero_iff] at Hcos
rcases Hcos with (⟨n, hn⟩ | ⟨n, hn⟩)
· right
rw [eq_div_iff_mul_eq (two_ne_zero' ℝ), ← sub_eq_iff_eq_add] at hn
rw [← hn, coe_sub, eq_neg_iff_add_eq_zero, sub_add_cancel, mul_assoc, intCast_mul_eq_zsmul,
mul_comm, coe_two_pi, zsmul_zero]
· left
rw [eq_div_iff_mul_eq (two_ne_zero' ℝ), eq_sub_iff_add_eq] at hn
rw [← hn, coe_add, mul_assoc, intCast_mul_eq_zsmul, mul_comm, coe_two_pi, zsmul_zero,
zero_add]
· rw [angle_eq_iff_two_pi_dvd_sub, ← coe_neg, angle_eq_iff_two_pi_dvd_sub]
rintro (⟨k, H⟩ | ⟨k, H⟩)
· rw [← sub_eq_zero, cos_sub_cos, H, mul_assoc 2 π k, mul_div_cancel_left₀ _ (two_ne_zero' ℝ),
mul_comm π _, sin_int_mul_pi, mul_zero]
rw [← sub_eq_zero, cos_sub_cos, ← sub_neg_eq_add, H, mul_assoc 2 π k,
mul_div_cancel_left₀ _ (two_ne_zero' ℝ), mul_comm π _, sin_int_mul_pi, mul_zero,
zero_mul]
#align real.angle.cos_eq_iff_coe_eq_or_eq_neg Real.Angle.cos_eq_iff_coe_eq_or_eq_neg
theorem sin_eq_iff_coe_eq_or_add_eq_pi {θ ψ : ℝ} :
sin θ = sin ψ ↔ (θ : Angle) = ψ ∨ (θ : Angle) + ψ = π := by
constructor
· intro Hsin
rw [← cos_pi_div_two_sub, ← cos_pi_div_two_sub] at Hsin
cases' cos_eq_iff_coe_eq_or_eq_neg.mp Hsin with h h
· left
rw [coe_sub, coe_sub] at h
exact sub_right_inj.1 h
right
rw [coe_sub, coe_sub, eq_neg_iff_add_eq_zero, add_sub, sub_add_eq_add_sub, ← coe_add,
add_halves, sub_sub, sub_eq_zero] at h
exact h.symm
· rw [angle_eq_iff_two_pi_dvd_sub, ← eq_sub_iff_add_eq, ← coe_sub, angle_eq_iff_two_pi_dvd_sub]
rintro (⟨k, H⟩ | ⟨k, H⟩)
· rw [← sub_eq_zero, sin_sub_sin, H, mul_assoc 2 π k, mul_div_cancel_left₀ _ (two_ne_zero' ℝ),
mul_comm π _, sin_int_mul_pi, mul_zero, zero_mul]
have H' : θ + ψ = 2 * k * π + π := by
rwa [← sub_add, sub_add_eq_add_sub, sub_eq_iff_eq_add, mul_assoc, mul_comm π _, ←
mul_assoc] at H
rw [← sub_eq_zero, sin_sub_sin, H', add_div, mul_assoc 2 _ π,
mul_div_cancel_left₀ _ (two_ne_zero' ℝ), cos_add_pi_div_two, sin_int_mul_pi, neg_zero,
mul_zero]
#align real.angle.sin_eq_iff_coe_eq_or_add_eq_pi Real.Angle.sin_eq_iff_coe_eq_or_add_eq_pi
theorem cos_sin_inj {θ ψ : ℝ} (Hcos : cos θ = cos ψ) (Hsin : sin θ = sin ψ) : (θ : Angle) = ψ := by
cases' cos_eq_iff_coe_eq_or_eq_neg.mp Hcos with hc hc; · exact hc
cases' sin_eq_iff_coe_eq_or_add_eq_pi.mp Hsin with hs hs; · exact hs
rw [eq_neg_iff_add_eq_zero, hs] at hc
obtain ⟨n, hn⟩ : ∃ n, n • _ = _ := QuotientAddGroup.leftRel_apply.mp (Quotient.exact' hc)
rw [← neg_one_mul, add_zero, ← sub_eq_zero, zsmul_eq_mul, ← mul_assoc, ← sub_mul, mul_eq_zero,
eq_false (ne_of_gt pi_pos), or_false_iff, sub_neg_eq_add, ← Int.cast_zero, ← Int.cast_one,
← Int.cast_ofNat, ← Int.cast_mul, ← Int.cast_add, Int.cast_inj] at hn
have : (n * 2 + 1) % (2 : ℤ) = 0 % (2 : ℤ) := congr_arg (· % (2 : ℤ)) hn
rw [add_comm, Int.add_mul_emod_self] at this
exact absurd this one_ne_zero
#align real.angle.cos_sin_inj Real.Angle.cos_sin_inj
def sin (θ : Angle) : ℝ :=
sin_periodic.lift θ
#align real.angle.sin Real.Angle.sin
@[simp]
theorem sin_coe (x : ℝ) : sin (x : Angle) = Real.sin x :=
rfl
#align real.angle.sin_coe Real.Angle.sin_coe
@[continuity]
theorem continuous_sin : Continuous sin :=
Real.continuous_sin.quotient_liftOn' _
#align real.angle.continuous_sin Real.Angle.continuous_sin
def cos (θ : Angle) : ℝ :=
cos_periodic.lift θ
#align real.angle.cos Real.Angle.cos
@[simp]
theorem cos_coe (x : ℝ) : cos (x : Angle) = Real.cos x :=
rfl
#align real.angle.cos_coe Real.Angle.cos_coe
@[continuity]
theorem continuous_cos : Continuous cos :=
Real.continuous_cos.quotient_liftOn' _
#align real.angle.continuous_cos Real.Angle.continuous_cos
theorem cos_eq_real_cos_iff_eq_or_eq_neg {θ : Angle} {ψ : ℝ} :
cos θ = Real.cos ψ ↔ θ = ψ ∨ θ = -ψ := by
induction θ using Real.Angle.induction_on
exact cos_eq_iff_coe_eq_or_eq_neg
#align real.angle.cos_eq_real_cos_iff_eq_or_eq_neg Real.Angle.cos_eq_real_cos_iff_eq_or_eq_neg
theorem cos_eq_iff_eq_or_eq_neg {θ ψ : Angle} : cos θ = cos ψ ↔ θ = ψ ∨ θ = -ψ := by
induction ψ using Real.Angle.induction_on
exact cos_eq_real_cos_iff_eq_or_eq_neg
#align real.angle.cos_eq_iff_eq_or_eq_neg Real.Angle.cos_eq_iff_eq_or_eq_neg
theorem sin_eq_real_sin_iff_eq_or_add_eq_pi {θ : Angle} {ψ : ℝ} :
sin θ = Real.sin ψ ↔ θ = ψ ∨ θ + ψ = π := by
induction θ using Real.Angle.induction_on
exact sin_eq_iff_coe_eq_or_add_eq_pi
#align real.angle.sin_eq_real_sin_iff_eq_or_add_eq_pi Real.Angle.sin_eq_real_sin_iff_eq_or_add_eq_pi
theorem sin_eq_iff_eq_or_add_eq_pi {θ ψ : Angle} : sin θ = sin ψ ↔ θ = ψ ∨ θ + ψ = π := by
induction ψ using Real.Angle.induction_on
exact sin_eq_real_sin_iff_eq_or_add_eq_pi
#align real.angle.sin_eq_iff_eq_or_add_eq_pi Real.Angle.sin_eq_iff_eq_or_add_eq_pi
@[simp]
theorem sin_zero : sin (0 : Angle) = 0 := by rw [← coe_zero, sin_coe, Real.sin_zero]
#align real.angle.sin_zero Real.Angle.sin_zero
-- Porting note (#10618): @[simp] can prove it
theorem sin_coe_pi : sin (π : Angle) = 0 := by rw [sin_coe, Real.sin_pi]
#align real.angle.sin_coe_pi Real.Angle.sin_coe_pi
theorem sin_eq_zero_iff {θ : Angle} : sin θ = 0 ↔ θ = 0 ∨ θ = π := by
nth_rw 1 [← sin_zero]
rw [sin_eq_iff_eq_or_add_eq_pi]
simp
#align real.angle.sin_eq_zero_iff Real.Angle.sin_eq_zero_iff
theorem sin_ne_zero_iff {θ : Angle} : sin θ ≠ 0 ↔ θ ≠ 0 ∧ θ ≠ π := by
rw [← not_or, ← sin_eq_zero_iff]
#align real.angle.sin_ne_zero_iff Real.Angle.sin_ne_zero_iff
@[simp]
theorem sin_neg (θ : Angle) : sin (-θ) = -sin θ := by
induction θ using Real.Angle.induction_on
exact Real.sin_neg _
#align real.angle.sin_neg Real.Angle.sin_neg
theorem sin_antiperiodic : Function.Antiperiodic sin (π : Angle) := by
intro θ
induction θ using Real.Angle.induction_on
exact Real.sin_antiperiodic _
#align real.angle.sin_antiperiodic Real.Angle.sin_antiperiodic
@[simp]
theorem sin_add_pi (θ : Angle) : sin (θ + π) = -sin θ :=
sin_antiperiodic θ
#align real.angle.sin_add_pi Real.Angle.sin_add_pi
@[simp]
theorem sin_sub_pi (θ : Angle) : sin (θ - π) = -sin θ :=
sin_antiperiodic.sub_eq θ
#align real.angle.sin_sub_pi Real.Angle.sin_sub_pi
@[simp]
theorem cos_zero : cos (0 : Angle) = 1 := by rw [← coe_zero, cos_coe, Real.cos_zero]
#align real.angle.cos_zero Real.Angle.cos_zero
-- Porting note (#10618): @[simp] can prove it
theorem cos_coe_pi : cos (π : Angle) = -1 := by rw [cos_coe, Real.cos_pi]
#align real.angle.cos_coe_pi Real.Angle.cos_coe_pi
@[simp]
theorem cos_neg (θ : Angle) : cos (-θ) = cos θ := by
induction θ using Real.Angle.induction_on
exact Real.cos_neg _
#align real.angle.cos_neg Real.Angle.cos_neg
theorem cos_antiperiodic : Function.Antiperiodic cos (π : Angle) := by
intro θ
induction θ using Real.Angle.induction_on
exact Real.cos_antiperiodic _
#align real.angle.cos_antiperiodic Real.Angle.cos_antiperiodic
@[simp]
theorem cos_add_pi (θ : Angle) : cos (θ + π) = -cos θ :=
cos_antiperiodic θ
#align real.angle.cos_add_pi Real.Angle.cos_add_pi
@[simp]
theorem cos_sub_pi (θ : Angle) : cos (θ - π) = -cos θ :=
cos_antiperiodic.sub_eq θ
#align real.angle.cos_sub_pi Real.Angle.cos_sub_pi
theorem cos_eq_zero_iff {θ : Angle} : cos θ = 0 ↔ θ = (π / 2 : ℝ) ∨ θ = (-π / 2 : ℝ) := by
rw [← cos_pi_div_two, ← cos_coe, cos_eq_iff_eq_or_eq_neg, ← coe_neg, ← neg_div]
#align real.angle.cos_eq_zero_iff Real.Angle.cos_eq_zero_iff
theorem sin_add (θ₁ θ₂ : Real.Angle) : sin (θ₁ + θ₂) = sin θ₁ * cos θ₂ + cos θ₁ * sin θ₂ := by
induction θ₁ using Real.Angle.induction_on
induction θ₂ using Real.Angle.induction_on
exact Real.sin_add _ _
#align real.angle.sin_add Real.Angle.sin_add
theorem cos_add (θ₁ θ₂ : Real.Angle) : cos (θ₁ + θ₂) = cos θ₁ * cos θ₂ - sin θ₁ * sin θ₂ := by
induction θ₂ using Real.Angle.induction_on
induction θ₁ using Real.Angle.induction_on
exact Real.cos_add _ _
#align real.angle.cos_add Real.Angle.cos_add
@[simp]
theorem cos_sq_add_sin_sq (θ : Real.Angle) : cos θ ^ 2 + sin θ ^ 2 = 1 := by
induction θ using Real.Angle.induction_on
exact Real.cos_sq_add_sin_sq _
#align real.angle.cos_sq_add_sin_sq Real.Angle.cos_sq_add_sin_sq
theorem sin_add_pi_div_two (θ : Angle) : sin (θ + ↑(π / 2)) = cos θ := by
induction θ using Real.Angle.induction_on
exact Real.sin_add_pi_div_two _
#align real.angle.sin_add_pi_div_two Real.Angle.sin_add_pi_div_two
theorem sin_sub_pi_div_two (θ : Angle) : sin (θ - ↑(π / 2)) = -cos θ := by
induction θ using Real.Angle.induction_on
exact Real.sin_sub_pi_div_two _
#align real.angle.sin_sub_pi_div_two Real.Angle.sin_sub_pi_div_two
theorem sin_pi_div_two_sub (θ : Angle) : sin (↑(π / 2) - θ) = cos θ := by
induction θ using Real.Angle.induction_on
exact Real.sin_pi_div_two_sub _
#align real.angle.sin_pi_div_two_sub Real.Angle.sin_pi_div_two_sub
theorem cos_add_pi_div_two (θ : Angle) : cos (θ + ↑(π / 2)) = -sin θ := by
induction θ using Real.Angle.induction_on
exact Real.cos_add_pi_div_two _
#align real.angle.cos_add_pi_div_two Real.Angle.cos_add_pi_div_two
theorem cos_sub_pi_div_two (θ : Angle) : cos (θ - ↑(π / 2)) = sin θ := by
induction θ using Real.Angle.induction_on
exact Real.cos_sub_pi_div_two _
#align real.angle.cos_sub_pi_div_two Real.Angle.cos_sub_pi_div_two
theorem cos_pi_div_two_sub (θ : Angle) : cos (↑(π / 2) - θ) = sin θ := by
induction θ using Real.Angle.induction_on
exact Real.cos_pi_div_two_sub _
#align real.angle.cos_pi_div_two_sub Real.Angle.cos_pi_div_two_sub
theorem abs_sin_eq_of_two_nsmul_eq {θ ψ : Angle} (h : (2 : ℕ) • θ = (2 : ℕ) • ψ) :
|sin θ| = |sin ψ| := by
rw [two_nsmul_eq_iff] at h
rcases h with (rfl | rfl)
· rfl
· rw [sin_add_pi, abs_neg]
#align real.angle.abs_sin_eq_of_two_nsmul_eq Real.Angle.abs_sin_eq_of_two_nsmul_eq
theorem abs_sin_eq_of_two_zsmul_eq {θ ψ : Angle} (h : (2 : ℤ) • θ = (2 : ℤ) • ψ) :
|sin θ| = |sin ψ| := by
simp_rw [two_zsmul, ← two_nsmul] at h
exact abs_sin_eq_of_two_nsmul_eq h
#align real.angle.abs_sin_eq_of_two_zsmul_eq Real.Angle.abs_sin_eq_of_two_zsmul_eq
theorem abs_cos_eq_of_two_nsmul_eq {θ ψ : Angle} (h : (2 : ℕ) • θ = (2 : ℕ) • ψ) :
|cos θ| = |cos ψ| := by
rw [two_nsmul_eq_iff] at h
rcases h with (rfl | rfl)
· rfl
· rw [cos_add_pi, abs_neg]
#align real.angle.abs_cos_eq_of_two_nsmul_eq Real.Angle.abs_cos_eq_of_two_nsmul_eq
theorem abs_cos_eq_of_two_zsmul_eq {θ ψ : Angle} (h : (2 : ℤ) • θ = (2 : ℤ) • ψ) :
|cos θ| = |cos ψ| := by
simp_rw [two_zsmul, ← two_nsmul] at h
exact abs_cos_eq_of_two_nsmul_eq h
#align real.angle.abs_cos_eq_of_two_zsmul_eq Real.Angle.abs_cos_eq_of_two_zsmul_eq
@[simp]
theorem coe_toIcoMod (θ ψ : ℝ) : ↑(toIcoMod two_pi_pos ψ θ) = (θ : Angle) := by
rw [angle_eq_iff_two_pi_dvd_sub]
refine ⟨-toIcoDiv two_pi_pos ψ θ, ?_⟩
rw [toIcoMod_sub_self, zsmul_eq_mul, mul_comm]
#align real.angle.coe_to_Ico_mod Real.Angle.coe_toIcoMod
@[simp]
theorem coe_toIocMod (θ ψ : ℝ) : ↑(toIocMod two_pi_pos ψ θ) = (θ : Angle) := by
rw [angle_eq_iff_two_pi_dvd_sub]
refine ⟨-toIocDiv two_pi_pos ψ θ, ?_⟩
rw [toIocMod_sub_self, zsmul_eq_mul, mul_comm]
#align real.angle.coe_to_Ioc_mod Real.Angle.coe_toIocMod
def toReal (θ : Angle) : ℝ :=
(toIocMod_periodic two_pi_pos (-π)).lift θ
#align real.angle.to_real Real.Angle.toReal
theorem toReal_coe (θ : ℝ) : (θ : Angle).toReal = toIocMod two_pi_pos (-π) θ :=
rfl
#align real.angle.to_real_coe Real.Angle.toReal_coe
theorem toReal_coe_eq_self_iff {θ : ℝ} : (θ : Angle).toReal = θ ↔ -π < θ ∧ θ ≤ π := by
rw [toReal_coe, toIocMod_eq_self two_pi_pos]
ring_nf
rfl
#align real.angle.to_real_coe_eq_self_iff Real.Angle.toReal_coe_eq_self_iff
theorem toReal_coe_eq_self_iff_mem_Ioc {θ : ℝ} : (θ : Angle).toReal = θ ↔ θ ∈ Set.Ioc (-π) π := by
rw [toReal_coe_eq_self_iff, ← Set.mem_Ioc]
#align real.angle.to_real_coe_eq_self_iff_mem_Ioc Real.Angle.toReal_coe_eq_self_iff_mem_Ioc
theorem toReal_injective : Function.Injective toReal := by
intro θ ψ h
induction θ using Real.Angle.induction_on
induction ψ using Real.Angle.induction_on
simpa [toReal_coe, toIocMod_eq_toIocMod, zsmul_eq_mul, mul_comm _ (2 * π), ←
angle_eq_iff_two_pi_dvd_sub, eq_comm] using h
#align real.angle.to_real_injective Real.Angle.toReal_injective
@[simp]
theorem toReal_inj {θ ψ : Angle} : θ.toReal = ψ.toReal ↔ θ = ψ :=
toReal_injective.eq_iff
#align real.angle.to_real_inj Real.Angle.toReal_inj
@[simp]
theorem coe_toReal (θ : Angle) : (θ.toReal : Angle) = θ := by
induction θ using Real.Angle.induction_on
exact coe_toIocMod _ _
#align real.angle.coe_to_real Real.Angle.coe_toReal
theorem neg_pi_lt_toReal (θ : Angle) : -π < θ.toReal := by
induction θ using Real.Angle.induction_on
exact left_lt_toIocMod _ _ _
#align real.angle.neg_pi_lt_to_real Real.Angle.neg_pi_lt_toReal
theorem toReal_le_pi (θ : Angle) : θ.toReal ≤ π := by
induction θ using Real.Angle.induction_on
convert toIocMod_le_right two_pi_pos _ _
ring
#align real.angle.to_real_le_pi Real.Angle.toReal_le_pi
theorem abs_toReal_le_pi (θ : Angle) : |θ.toReal| ≤ π :=
abs_le.2 ⟨(neg_pi_lt_toReal _).le, toReal_le_pi _⟩
#align real.angle.abs_to_real_le_pi Real.Angle.abs_toReal_le_pi
theorem toReal_mem_Ioc (θ : Angle) : θ.toReal ∈ Set.Ioc (-π) π :=
⟨neg_pi_lt_toReal _, toReal_le_pi _⟩
#align real.angle.to_real_mem_Ioc Real.Angle.toReal_mem_Ioc
@[simp]
theorem toIocMod_toReal (θ : Angle) : toIocMod two_pi_pos (-π) θ.toReal = θ.toReal := by
induction θ using Real.Angle.induction_on
rw [toReal_coe]
exact toIocMod_toIocMod _ _ _ _
#align real.angle.to_Ioc_mod_to_real Real.Angle.toIocMod_toReal
@[simp]
theorem toReal_zero : (0 : Angle).toReal = 0 := by
rw [← coe_zero, toReal_coe_eq_self_iff]
exact ⟨Left.neg_neg_iff.2 Real.pi_pos, Real.pi_pos.le⟩
#align real.angle.to_real_zero Real.Angle.toReal_zero
@[simp]
theorem toReal_eq_zero_iff {θ : Angle} : θ.toReal = 0 ↔ θ = 0 := by
nth_rw 1 [← toReal_zero]
exact toReal_inj
#align real.angle.to_real_eq_zero_iff Real.Angle.toReal_eq_zero_iff
@[simp]
theorem toReal_pi : (π : Angle).toReal = π := by
rw [toReal_coe_eq_self_iff]
exact ⟨Left.neg_lt_self Real.pi_pos, le_refl _⟩
#align real.angle.to_real_pi Real.Angle.toReal_pi
@[simp]
theorem toReal_eq_pi_iff {θ : Angle} : θ.toReal = π ↔ θ = π := by rw [← toReal_inj, toReal_pi]
#align real.angle.to_real_eq_pi_iff Real.Angle.toReal_eq_pi_iff
theorem pi_ne_zero : (π : Angle) ≠ 0 := by
rw [← toReal_injective.ne_iff, toReal_pi, toReal_zero]
exact Real.pi_ne_zero
#align real.angle.pi_ne_zero Real.Angle.pi_ne_zero
@[simp]
theorem toReal_pi_div_two : ((π / 2 : ℝ) : Angle).toReal = π / 2 :=
toReal_coe_eq_self_iff.2 <| by constructor <;> linarith [pi_pos]
#align real.angle.to_real_pi_div_two Real.Angle.toReal_pi_div_two
@[simp]
theorem toReal_eq_pi_div_two_iff {θ : Angle} : θ.toReal = π / 2 ↔ θ = (π / 2 : ℝ) := by
rw [← toReal_inj, toReal_pi_div_two]
#align real.angle.to_real_eq_pi_div_two_iff Real.Angle.toReal_eq_pi_div_two_iff
@[simp]
theorem toReal_neg_pi_div_two : ((-π / 2 : ℝ) : Angle).toReal = -π / 2 :=
toReal_coe_eq_self_iff.2 <| by constructor <;> linarith [pi_pos]
#align real.angle.to_real_neg_pi_div_two Real.Angle.toReal_neg_pi_div_two
@[simp]
theorem toReal_eq_neg_pi_div_two_iff {θ : Angle} : θ.toReal = -π / 2 ↔ θ = (-π / 2 : ℝ) := by
rw [← toReal_inj, toReal_neg_pi_div_two]
#align real.angle.to_real_eq_neg_pi_div_two_iff Real.Angle.toReal_eq_neg_pi_div_two_iff
theorem pi_div_two_ne_zero : ((π / 2 : ℝ) : Angle) ≠ 0 := by
rw [← toReal_injective.ne_iff, toReal_pi_div_two, toReal_zero]
exact div_ne_zero Real.pi_ne_zero two_ne_zero
#align real.angle.pi_div_two_ne_zero Real.Angle.pi_div_two_ne_zero
theorem neg_pi_div_two_ne_zero : ((-π / 2 : ℝ) : Angle) ≠ 0 := by
rw [← toReal_injective.ne_iff, toReal_neg_pi_div_two, toReal_zero]
exact div_ne_zero (neg_ne_zero.2 Real.pi_ne_zero) two_ne_zero
#align real.angle.neg_pi_div_two_ne_zero Real.Angle.neg_pi_div_two_ne_zero
theorem abs_toReal_coe_eq_self_iff {θ : ℝ} : |(θ : Angle).toReal| = θ ↔ 0 ≤ θ ∧ θ ≤ π :=
⟨fun h => h ▸ ⟨abs_nonneg _, abs_toReal_le_pi _⟩, fun h =>
(toReal_coe_eq_self_iff.2 ⟨(Left.neg_neg_iff.2 Real.pi_pos).trans_le h.1, h.2⟩).symm ▸
abs_eq_self.2 h.1⟩
#align real.angle.abs_to_real_coe_eq_self_iff Real.Angle.abs_toReal_coe_eq_self_iff
theorem abs_toReal_neg_coe_eq_self_iff {θ : ℝ} : |(-θ : Angle).toReal| = θ ↔ 0 ≤ θ ∧ θ ≤ π := by
refine ⟨fun h => h ▸ ⟨abs_nonneg _, abs_toReal_le_pi _⟩, fun h => ?_⟩
by_cases hnegpi : θ = π; · simp [hnegpi, Real.pi_pos.le]
rw [← coe_neg,
toReal_coe_eq_self_iff.2
⟨neg_lt_neg (lt_of_le_of_ne h.2 hnegpi), (neg_nonpos.2 h.1).trans Real.pi_pos.le⟩,
abs_neg, abs_eq_self.2 h.1]
#align real.angle.abs_to_real_neg_coe_eq_self_iff Real.Angle.abs_toReal_neg_coe_eq_self_iff
theorem abs_toReal_eq_pi_div_two_iff {θ : Angle} :
|θ.toReal| = π / 2 ↔ θ = (π / 2 : ℝ) ∨ θ = (-π / 2 : ℝ) := by
rw [abs_eq (div_nonneg Real.pi_pos.le two_pos.le), ← neg_div, toReal_eq_pi_div_two_iff,
toReal_eq_neg_pi_div_two_iff]
#align real.angle.abs_to_real_eq_pi_div_two_iff Real.Angle.abs_toReal_eq_pi_div_two_iff
theorem nsmul_toReal_eq_mul {n : ℕ} (h : n ≠ 0) {θ : Angle} :
(n • θ).toReal = n * θ.toReal ↔ θ.toReal ∈ Set.Ioc (-π / n) (π / n) := by
nth_rw 1 [← coe_toReal θ]
have h' : 0 < (n : ℝ) := mod_cast Nat.pos_of_ne_zero h
rw [← coe_nsmul, nsmul_eq_mul, toReal_coe_eq_self_iff, Set.mem_Ioc, div_lt_iff' h',
le_div_iff' h']
#align real.angle.nsmul_to_real_eq_mul Real.Angle.nsmul_toReal_eq_mul
theorem two_nsmul_toReal_eq_two_mul {θ : Angle} :
((2 : ℕ) • θ).toReal = 2 * θ.toReal ↔ θ.toReal ∈ Set.Ioc (-π / 2) (π / 2) :=
mod_cast nsmul_toReal_eq_mul two_ne_zero
#align real.angle.two_nsmul_to_real_eq_two_mul Real.Angle.two_nsmul_toReal_eq_two_mul
theorem two_zsmul_toReal_eq_two_mul {θ : Angle} :
((2 : ℤ) • θ).toReal = 2 * θ.toReal ↔ θ.toReal ∈ Set.Ioc (-π / 2) (π / 2) := by
rw [two_zsmul, ← two_nsmul, two_nsmul_toReal_eq_two_mul]
#align real.angle.two_zsmul_to_real_eq_two_mul Real.Angle.two_zsmul_toReal_eq_two_mul
theorem toReal_coe_eq_self_sub_two_mul_int_mul_pi_iff {θ : ℝ} {k : ℤ} :
(θ : Angle).toReal = θ - 2 * k * π ↔ θ ∈ Set.Ioc ((2 * k - 1 : ℝ) * π) ((2 * k + 1) * π) := by
rw [← sub_zero (θ : Angle), ← zsmul_zero k, ← coe_two_pi, ← coe_zsmul, ← coe_sub, zsmul_eq_mul, ←
mul_assoc, mul_comm (k : ℝ), toReal_coe_eq_self_iff, Set.mem_Ioc]
exact ⟨fun h => ⟨by linarith, by linarith⟩, fun h => ⟨by linarith, by linarith⟩⟩
#align real.angle.to_real_coe_eq_self_sub_two_mul_int_mul_pi_iff Real.Angle.toReal_coe_eq_self_sub_two_mul_int_mul_pi_iff
theorem toReal_coe_eq_self_sub_two_pi_iff {θ : ℝ} :
(θ : Angle).toReal = θ - 2 * π ↔ θ ∈ Set.Ioc π (3 * π) := by
convert @toReal_coe_eq_self_sub_two_mul_int_mul_pi_iff θ 1 <;> norm_num
#align real.angle.to_real_coe_eq_self_sub_two_pi_iff Real.Angle.toReal_coe_eq_self_sub_two_pi_iff
theorem toReal_coe_eq_self_add_two_pi_iff {θ : ℝ} :
(θ : Angle).toReal = θ + 2 * π ↔ θ ∈ Set.Ioc (-3 * π) (-π) := by
convert @toReal_coe_eq_self_sub_two_mul_int_mul_pi_iff θ (-1) using 2 <;>
set_option tactic.skipAssignedInstances false in norm_num
#align real.angle.to_real_coe_eq_self_add_two_pi_iff Real.Angle.toReal_coe_eq_self_add_two_pi_iff
theorem two_nsmul_toReal_eq_two_mul_sub_two_pi {θ : Angle} :
((2 : ℕ) • θ).toReal = 2 * θ.toReal - 2 * π ↔ π / 2 < θ.toReal := by
nth_rw 1 [← coe_toReal θ]
rw [← coe_nsmul, two_nsmul, ← two_mul, toReal_coe_eq_self_sub_two_pi_iff, Set.mem_Ioc]
exact
⟨fun h => by linarith, fun h =>
⟨(div_lt_iff' (zero_lt_two' ℝ)).1 h, by linarith [pi_pos, toReal_le_pi θ]⟩⟩
#align real.angle.two_nsmul_to_real_eq_two_mul_sub_two_pi Real.Angle.two_nsmul_toReal_eq_two_mul_sub_two_pi
theorem two_zsmul_toReal_eq_two_mul_sub_two_pi {θ : Angle} :
((2 : ℤ) • θ).toReal = 2 * θ.toReal - 2 * π ↔ π / 2 < θ.toReal := by
rw [two_zsmul, ← two_nsmul, two_nsmul_toReal_eq_two_mul_sub_two_pi]
#align real.angle.two_zsmul_to_real_eq_two_mul_sub_two_pi Real.Angle.two_zsmul_toReal_eq_two_mul_sub_two_pi
theorem two_nsmul_toReal_eq_two_mul_add_two_pi {θ : Angle} :
((2 : ℕ) • θ).toReal = 2 * θ.toReal + 2 * π ↔ θ.toReal ≤ -π / 2 := by
nth_rw 1 [← coe_toReal θ]
rw [← coe_nsmul, two_nsmul, ← two_mul, toReal_coe_eq_self_add_two_pi_iff, Set.mem_Ioc]
refine
⟨fun h => by linarith, fun h =>
⟨by linarith [pi_pos, neg_pi_lt_toReal θ], (le_div_iff' (zero_lt_two' ℝ)).1 h⟩⟩
#align real.angle.two_nsmul_to_real_eq_two_mul_add_two_pi Real.Angle.two_nsmul_toReal_eq_two_mul_add_two_pi
| Mathlib/Analysis/SpecialFunctions/Trigonometric/Angle.lean | 722 | 724 | theorem two_zsmul_toReal_eq_two_mul_add_two_pi {θ : Angle} :
((2 : ℤ) • θ).toReal = 2 * θ.toReal + 2 * π ↔ θ.toReal ≤ -π / 2 := by |
rw [two_zsmul, ← two_nsmul, two_nsmul_toReal_eq_two_mul_add_two_pi]
|
import Mathlib.Data.Nat.Prime
import Mathlib.Data.PNat.Basic
#align_import data.pnat.prime from "leanprover-community/mathlib"@"09597669f02422ed388036273d8848119699c22f"
namespace PNat
open Nat
def gcd (n m : ℕ+) : ℕ+ :=
⟨Nat.gcd (n : ℕ) (m : ℕ), Nat.gcd_pos_of_pos_left (m : ℕ) n.pos⟩
#align pnat.gcd PNat.gcd
def lcm (n m : ℕ+) : ℕ+ :=
⟨Nat.lcm (n : ℕ) (m : ℕ), by
let h := mul_pos n.pos m.pos
rw [← gcd_mul_lcm (n : ℕ) (m : ℕ), mul_comm] at h
exact pos_of_dvd_of_pos (Dvd.intro (Nat.gcd (n : ℕ) (m : ℕ)) rfl) h⟩
#align pnat.lcm PNat.lcm
@[simp, norm_cast]
theorem gcd_coe (n m : ℕ+) : (gcd n m : ℕ) = Nat.gcd n m :=
rfl
#align pnat.gcd_coe PNat.gcd_coe
@[simp, norm_cast]
theorem lcm_coe (n m : ℕ+) : (lcm n m : ℕ) = Nat.lcm n m :=
rfl
#align pnat.lcm_coe PNat.lcm_coe
theorem gcd_dvd_left (n m : ℕ+) : gcd n m ∣ n :=
dvd_iff.2 (Nat.gcd_dvd_left (n : ℕ) (m : ℕ))
#align pnat.gcd_dvd_left PNat.gcd_dvd_left
theorem gcd_dvd_right (n m : ℕ+) : gcd n m ∣ m :=
dvd_iff.2 (Nat.gcd_dvd_right (n : ℕ) (m : ℕ))
#align pnat.gcd_dvd_right PNat.gcd_dvd_right
theorem dvd_gcd {m n k : ℕ+} (hm : k ∣ m) (hn : k ∣ n) : k ∣ gcd m n :=
dvd_iff.2 (Nat.dvd_gcd (dvd_iff.1 hm) (dvd_iff.1 hn))
#align pnat.dvd_gcd PNat.dvd_gcd
theorem dvd_lcm_left (n m : ℕ+) : n ∣ lcm n m :=
dvd_iff.2 (Nat.dvd_lcm_left (n : ℕ) (m : ℕ))
#align pnat.dvd_lcm_left PNat.dvd_lcm_left
theorem dvd_lcm_right (n m : ℕ+) : m ∣ lcm n m :=
dvd_iff.2 (Nat.dvd_lcm_right (n : ℕ) (m : ℕ))
#align pnat.dvd_lcm_right PNat.dvd_lcm_right
theorem lcm_dvd {m n k : ℕ+} (hm : m ∣ k) (hn : n ∣ k) : lcm m n ∣ k :=
dvd_iff.2 (@Nat.lcm_dvd (m : ℕ) (n : ℕ) (k : ℕ) (dvd_iff.1 hm) (dvd_iff.1 hn))
#align pnat.lcm_dvd PNat.lcm_dvd
theorem gcd_mul_lcm (n m : ℕ+) : gcd n m * lcm n m = n * m :=
Subtype.eq (Nat.gcd_mul_lcm (n : ℕ) (m : ℕ))
#align pnat.gcd_mul_lcm PNat.gcd_mul_lcm
theorem eq_one_of_lt_two {n : ℕ+} : n < 2 → n = 1 := by
intro h; apply le_antisymm; swap
· apply PNat.one_le
· exact PNat.lt_add_one_iff.1 h
#align pnat.eq_one_of_lt_two PNat.eq_one_of_lt_two
section Coprime
def Coprime (m n : ℕ+) : Prop :=
m.gcd n = 1
#align pnat.coprime PNat.Coprime
@[simp, norm_cast]
theorem coprime_coe {m n : ℕ+} : Nat.Coprime ↑m ↑n ↔ m.Coprime n := by
unfold Nat.Coprime Coprime
rw [← coe_inj]
simp
#align pnat.coprime_coe PNat.coprime_coe
theorem Coprime.mul {k m n : ℕ+} : m.Coprime k → n.Coprime k → (m * n).Coprime k := by
repeat rw [← coprime_coe]
rw [mul_coe]
apply Nat.Coprime.mul
#align pnat.coprime.mul PNat.Coprime.mul
theorem Coprime.mul_right {k m n : ℕ+} : k.Coprime m → k.Coprime n → k.Coprime (m * n) := by
repeat rw [← coprime_coe]
rw [mul_coe]
apply Nat.Coprime.mul_right
#align pnat.coprime.mul_right PNat.Coprime.mul_right
theorem gcd_comm {m n : ℕ+} : m.gcd n = n.gcd m := by
apply eq
simp only [gcd_coe]
apply Nat.gcd_comm
#align pnat.gcd_comm PNat.gcd_comm
theorem gcd_eq_left_iff_dvd {m n : ℕ+} : m ∣ n ↔ m.gcd n = m := by
rw [dvd_iff]
rw [Nat.gcd_eq_left_iff_dvd]
rw [← coe_inj]
simp
#align pnat.gcd_eq_left_iff_dvd PNat.gcd_eq_left_iff_dvd
theorem gcd_eq_right_iff_dvd {m n : ℕ+} : m ∣ n ↔ n.gcd m = m := by
rw [gcd_comm]
apply gcd_eq_left_iff_dvd
#align pnat.gcd_eq_right_iff_dvd PNat.gcd_eq_right_iff_dvd
theorem Coprime.gcd_mul_left_cancel (m : ℕ+) {n k : ℕ+} :
k.Coprime n → (k * m).gcd n = m.gcd n := by
intro h; apply eq; simp only [gcd_coe, mul_coe]
apply Nat.Coprime.gcd_mul_left_cancel; simpa
#align pnat.coprime.gcd_mul_left_cancel PNat.Coprime.gcd_mul_left_cancel
theorem Coprime.gcd_mul_right_cancel (m : ℕ+) {n k : ℕ+} :
k.Coprime n → (m * k).gcd n = m.gcd n := by rw [mul_comm]; apply Coprime.gcd_mul_left_cancel
#align pnat.coprime.gcd_mul_right_cancel PNat.Coprime.gcd_mul_right_cancel
theorem Coprime.gcd_mul_left_cancel_right (m : ℕ+) {n k : ℕ+} :
k.Coprime m → m.gcd (k * n) = m.gcd n := by
intro h; iterate 2 rw [gcd_comm]; symm;
apply Coprime.gcd_mul_left_cancel _ h
#align pnat.coprime.gcd_mul_left_cancel_right PNat.Coprime.gcd_mul_left_cancel_right
| Mathlib/Data/PNat/Prime.lean | 238 | 241 | theorem Coprime.gcd_mul_right_cancel_right (m : ℕ+) {n k : ℕ+} :
k.Coprime m → m.gcd (n * k) = m.gcd n := by |
rw [mul_comm];
apply Coprime.gcd_mul_left_cancel_right
|
import Mathlib.MeasureTheory.Constructions.BorelSpace.Order
#align_import measure_theory.constructions.borel_space.basic from "leanprover-community/mathlib"@"9f55d0d4363ae59948c33864cbc52e0b12e0e8ce"
open Set Filter MeasureTheory MeasurableSpace
open scoped Classical Topology NNReal ENNReal MeasureTheory
universe u v w x y
variable {α β γ δ : Type*} {ι : Sort y} {s t u : Set α}
namespace Real
theorem borel_eq_generateFrom_Ioo_rat :
borel ℝ = .generateFrom (⋃ (a : ℚ) (b : ℚ) (_ : a < b), {Ioo (a : ℝ) (b : ℝ)}) :=
isTopologicalBasis_Ioo_rat.borel_eq_generateFrom
#align real.borel_eq_generate_from_Ioo_rat Real.borel_eq_generateFrom_Ioo_rat
theorem borel_eq_generateFrom_Iio_rat : borel ℝ = .generateFrom (⋃ a : ℚ, {Iio (a : ℝ)}) := by
rw [borel_eq_generateFrom_Iio]
refine le_antisymm
(generateFrom_le ?_)
(generateFrom_mono <| iUnion_subset fun q ↦ singleton_subset_iff.mpr <| mem_range_self _)
rintro _ ⟨a, rfl⟩
have : IsLUB (range ((↑) : ℚ → ℝ) ∩ Iio a) a := by
simp [isLUB_iff_le_iff, mem_upperBounds, ← le_iff_forall_rat_lt_imp_le]
rw [← this.biUnion_Iio_eq, ← image_univ, ← image_inter_preimage, univ_inter, biUnion_image]
exact MeasurableSet.biUnion (to_countable _)
fun b _ => GenerateMeasurable.basic (Iio (b : ℝ)) (by simp)
theorem borel_eq_generateFrom_Ioi_rat : borel ℝ = .generateFrom (⋃ a : ℚ, {Ioi (a : ℝ)}) := by
rw [borel_eq_generateFrom_Ioi]
refine le_antisymm
(generateFrom_le ?_)
(generateFrom_mono <| iUnion_subset fun q ↦ singleton_subset_iff.mpr <| mem_range_self _)
rintro _ ⟨a, rfl⟩
have : IsGLB (range ((↑) : ℚ → ℝ) ∩ Ioi a) a := by
simp [isGLB_iff_le_iff, mem_lowerBounds, ← le_iff_forall_lt_rat_imp_le]
rw [← this.biUnion_Ioi_eq, ← image_univ, ← image_inter_preimage, univ_inter, biUnion_image]
exact MeasurableSet.biUnion (to_countable _)
fun b _ => GenerateMeasurable.basic (Ioi (b : ℝ)) (by simp)
theorem borel_eq_generateFrom_Iic_rat : borel ℝ = .generateFrom (⋃ a : ℚ, {Iic (a : ℝ)}) := by
rw [borel_eq_generateFrom_Ioi_rat, iUnion_singleton_eq_range, iUnion_singleton_eq_range]
refine le_antisymm (generateFrom_le ?_) (generateFrom_le ?_) <;>
rintro _ ⟨q, rfl⟩ <;>
dsimp only <;>
[rw [← compl_Iic]; rw [← compl_Ioi]] <;>
exact MeasurableSet.compl (GenerateMeasurable.basic _ (mem_range_self q))
| Mathlib/MeasureTheory/Constructions/BorelSpace/Real.lean | 76 | 82 | theorem borel_eq_generateFrom_Ici_rat : borel ℝ = .generateFrom (⋃ a : ℚ, {Ici (a : ℝ)}) := by |
rw [borel_eq_generateFrom_Iio_rat, iUnion_singleton_eq_range, iUnion_singleton_eq_range]
refine le_antisymm (generateFrom_le ?_) (generateFrom_le ?_) <;>
rintro _ ⟨q, rfl⟩ <;>
dsimp only <;>
[rw [← compl_Ici]; rw [← compl_Iio]] <;>
exact MeasurableSet.compl (GenerateMeasurable.basic _ (mem_range_self q))
|
import Mathlib.Topology.Category.TopCat.Limits.Pullbacks
import Mathlib.Geometry.RingedSpace.LocallyRingedSpace
#align_import algebraic_geometry.open_immersion.basic from "leanprover-community/mathlib"@"533f62f4dd62a5aad24a04326e6e787c8f7e98b1"
-- Porting note: due to `PresheafedSpace`, `SheafedSpace` and `LocallyRingedSpace`
set_option linter.uppercaseLean3 false
open TopologicalSpace CategoryTheory Opposite
open CategoryTheory.Limits
namespace AlgebraicGeometry
universe v v₁ v₂ u
variable {C : Type u} [Category.{v} C]
class PresheafedSpace.IsOpenImmersion {X Y : PresheafedSpace C} (f : X ⟶ Y) : Prop where
base_open : OpenEmbedding f.base
c_iso : ∀ U : Opens X, IsIso (f.c.app (op (base_open.isOpenMap.functor.obj U)))
#align algebraic_geometry.PresheafedSpace.is_open_immersion AlgebraicGeometry.PresheafedSpace.IsOpenImmersion
abbrev SheafedSpace.IsOpenImmersion {X Y : SheafedSpace C} (f : X ⟶ Y) : Prop :=
PresheafedSpace.IsOpenImmersion f
#align algebraic_geometry.SheafedSpace.is_open_immersion AlgebraicGeometry.SheafedSpace.IsOpenImmersion
abbrev LocallyRingedSpace.IsOpenImmersion {X Y : LocallyRingedSpace} (f : X ⟶ Y) : Prop :=
SheafedSpace.IsOpenImmersion f.1
#align algebraic_geometry.LocallyRingedSpace.is_open_immersion AlgebraicGeometry.LocallyRingedSpace.IsOpenImmersion
namespace PresheafedSpace.IsOpenImmersion
open PresheafedSpace
local notation "IsOpenImmersion" => PresheafedSpace.IsOpenImmersion
attribute [instance] IsOpenImmersion.c_iso
section
variable {X Y : PresheafedSpace C} {f : X ⟶ Y} (H : IsOpenImmersion f)
abbrev openFunctor :=
H.base_open.isOpenMap.functor
#align algebraic_geometry.PresheafedSpace.is_open_immersion.open_functor AlgebraicGeometry.PresheafedSpace.IsOpenImmersion.openFunctor
@[simps! hom_c_app]
noncomputable def isoRestrict : X ≅ Y.restrict H.base_open :=
PresheafedSpace.isoOfComponents (Iso.refl _) <| by
symm
fapply NatIso.ofComponents
· intro U
refine asIso (f.c.app (op (H.openFunctor.obj (unop U)))) ≪≫ X.presheaf.mapIso (eqToIso ?_)
induction U using Opposite.rec' with | h U => ?_
cases U
dsimp only [IsOpenMap.functor, Functor.op, Opens.map]
congr 2
erw [Set.preimage_image_eq _ H.base_open.inj]
rfl
· intro U V i
simp only [CategoryTheory.eqToIso.hom, TopCat.Presheaf.pushforwardObj_map, Category.assoc,
Functor.op_map, Iso.trans_hom, asIso_hom, Functor.mapIso_hom, ← X.presheaf.map_comp]
erw [f.c.naturality_assoc, ← X.presheaf.map_comp]
congr 1
#align algebraic_geometry.PresheafedSpace.is_open_immersion.iso_restrict AlgebraicGeometry.PresheafedSpace.IsOpenImmersion.isoRestrict
@[simp]
theorem isoRestrict_hom_ofRestrict : H.isoRestrict.hom ≫ Y.ofRestrict _ = f := by
-- Porting note: `ext` did not pick up `NatTrans.ext`
refine PresheafedSpace.Hom.ext _ _ rfl <| NatTrans.ext _ _ <| funext fun x => ?_
simp only [isoRestrict_hom_c_app, NatTrans.comp_app, eqToHom_refl,
ofRestrict_c_app, Category.assoc, whiskerRight_id']
erw [Category.comp_id, comp_c_app, f.c.naturality_assoc, ← X.presheaf.map_comp]
trans f.c.app x ≫ X.presheaf.map (𝟙 _)
· congr 1
· erw [X.presheaf.map_id, Category.comp_id]
#align algebraic_geometry.PresheafedSpace.is_open_immersion.iso_restrict_hom_of_restrict AlgebraicGeometry.PresheafedSpace.IsOpenImmersion.isoRestrict_hom_ofRestrict
@[simp]
| Mathlib/Geometry/RingedSpace/OpenImmersion.lean | 145 | 146 | theorem isoRestrict_inv_ofRestrict : H.isoRestrict.inv ≫ f = Y.ofRestrict _ := by |
rw [Iso.inv_comp_eq, isoRestrict_hom_ofRestrict]
|
import Mathlib.Data.Matrix.Basis
import Mathlib.LinearAlgebra.Basis
import Mathlib.LinearAlgebra.Pi
#align_import linear_algebra.std_basis from "leanprover-community/mathlib"@"13bce9a6b6c44f6b4c91ac1c1d2a816e2533d395"
open Function Set Submodule
namespace LinearMap
variable (R : Type*) {ι : Type*} [Semiring R] (φ : ι → Type*) [∀ i, AddCommMonoid (φ i)]
[∀ i, Module R (φ i)] [DecidableEq ι]
def stdBasis : ∀ i : ι, φ i →ₗ[R] ∀ i, φ i :=
single
#align linear_map.std_basis LinearMap.stdBasis
theorem stdBasis_apply (i : ι) (b : φ i) : stdBasis R φ i b = update (0 : (a : ι) → φ a) i b :=
rfl
#align linear_map.std_basis_apply LinearMap.stdBasis_apply
@[simp]
theorem stdBasis_apply' (i i' : ι) : (stdBasis R (fun _x : ι => R) i) 1 i' = ite (i = i') 1 0 := by
rw [LinearMap.stdBasis_apply, Function.update_apply, Pi.zero_apply]
congr 1; rw [eq_iff_iff, eq_comm]
#align linear_map.std_basis_apply' LinearMap.stdBasis_apply'
theorem coe_stdBasis (i : ι) : ⇑(stdBasis R φ i) = Pi.single i :=
rfl
#align linear_map.coe_std_basis LinearMap.coe_stdBasis
@[simp]
theorem stdBasis_same (i : ι) (b : φ i) : stdBasis R φ i b i = b :=
Pi.single_eq_same i b
#align linear_map.std_basis_same LinearMap.stdBasis_same
theorem stdBasis_ne (i j : ι) (h : j ≠ i) (b : φ i) : stdBasis R φ i b j = 0 :=
Pi.single_eq_of_ne h b
#align linear_map.std_basis_ne LinearMap.stdBasis_ne
theorem stdBasis_eq_pi_diag (i : ι) : stdBasis R φ i = pi (diag i) := by
ext x j
-- Porting note: made types explicit
convert (update_apply (R := R) (φ := φ) (ι := ι) 0 x i j _).symm
rfl
#align linear_map.std_basis_eq_pi_diag LinearMap.stdBasis_eq_pi_diag
theorem ker_stdBasis (i : ι) : ker (stdBasis R φ i) = ⊥ :=
ker_eq_bot_of_injective <| Pi.single_injective _ _
#align linear_map.ker_std_basis LinearMap.ker_stdBasis
theorem proj_comp_stdBasis (i j : ι) : (proj i).comp (stdBasis R φ j) = diag j i := by
rw [stdBasis_eq_pi_diag, proj_pi]
#align linear_map.proj_comp_std_basis LinearMap.proj_comp_stdBasis
theorem proj_stdBasis_same (i : ι) : (proj i).comp (stdBasis R φ i) = id :=
LinearMap.ext <| stdBasis_same R φ i
#align linear_map.proj_std_basis_same LinearMap.proj_stdBasis_same
theorem proj_stdBasis_ne (i j : ι) (h : i ≠ j) : (proj i).comp (stdBasis R φ j) = 0 :=
LinearMap.ext <| stdBasis_ne R φ _ _ h
#align linear_map.proj_std_basis_ne LinearMap.proj_stdBasis_ne
theorem iSup_range_stdBasis_le_iInf_ker_proj (I J : Set ι) (h : Disjoint I J) :
⨆ i ∈ I, range (stdBasis R φ i) ≤ ⨅ i ∈ J, ker (proj i : (∀ i, φ i) →ₗ[R] φ i) := by
refine iSup_le fun i => iSup_le fun hi => range_le_iff_comap.2 ?_
simp only [← ker_comp, eq_top_iff, SetLike.le_def, mem_ker, comap_iInf, mem_iInf]
rintro b - j hj
rw [proj_stdBasis_ne R φ j i, zero_apply]
rintro rfl
exact h.le_bot ⟨hi, hj⟩
#align linear_map.supr_range_std_basis_le_infi_ker_proj LinearMap.iSup_range_stdBasis_le_iInf_ker_proj
theorem iInf_ker_proj_le_iSup_range_stdBasis {I : Finset ι} {J : Set ι} (hu : Set.univ ⊆ ↑I ∪ J) :
⨅ i ∈ J, ker (proj i : (∀ i, φ i) →ₗ[R] φ i) ≤ ⨆ i ∈ I, range (stdBasis R φ i) :=
SetLike.le_def.2
(by
intro b hb
simp only [mem_iInf, mem_ker, proj_apply] at hb
rw [←
show (∑ i ∈ I, stdBasis R φ i (b i)) = b by
ext i
rw [Finset.sum_apply, ← stdBasis_same R φ i (b i)]
refine Finset.sum_eq_single i (fun j _ ne => stdBasis_ne _ _ _ _ ne.symm _) ?_
intro hiI
rw [stdBasis_same]
exact hb _ ((hu trivial).resolve_left hiI)]
exact sum_mem_biSup fun i _ => mem_range_self (stdBasis R φ i) (b i))
#align linear_map.infi_ker_proj_le_supr_range_std_basis LinearMap.iInf_ker_proj_le_iSup_range_stdBasis
| Mathlib/LinearAlgebra/StdBasis.lean | 123 | 129 | theorem iSup_range_stdBasis_eq_iInf_ker_proj {I J : Set ι} (hd : Disjoint I J)
(hu : Set.univ ⊆ I ∪ J) (hI : Set.Finite I) :
⨆ i ∈ I, range (stdBasis R φ i) = ⨅ i ∈ J, ker (proj i : (∀ i, φ i) →ₗ[R] φ i) := by |
refine le_antisymm (iSup_range_stdBasis_le_iInf_ker_proj _ _ _ _ hd) ?_
have : Set.univ ⊆ ↑hI.toFinset ∪ J := by rwa [hI.coe_toFinset]
refine le_trans (iInf_ker_proj_le_iSup_range_stdBasis R φ this) (iSup_mono fun i => ?_)
rw [Set.Finite.mem_toFinset]
|
import Batteries.Data.List.Lemmas
import Batteries.Data.Array.Basic
import Batteries.Tactic.SeqFocus
import Batteries.Util.ProofWanted
namespace Array
theorem forIn_eq_data_forIn [Monad m]
(as : Array α) (b : β) (f : α → β → m (ForInStep β)) :
forIn as b f = forIn as.data b f := by
let rec loop : ∀ {i h b j}, j + i = as.size →
Array.forIn.loop as f i h b = forIn (as.data.drop j) b f
| 0, _, _, _, rfl => by rw [List.drop_length]; rfl
| i+1, _, _, j, ij => by
simp only [forIn.loop, Nat.add]
have j_eq : j = size as - 1 - i := by simp [← ij, ← Nat.add_assoc]
have : as.size - 1 - i < as.size := j_eq ▸ ij ▸ Nat.lt_succ_of_le (Nat.le_add_right ..)
have : as[size as - 1 - i] :: as.data.drop (j + 1) = as.data.drop j := by
rw [j_eq]; exact List.get_cons_drop _ ⟨_, this⟩
simp only [← this, List.forIn_cons]; congr; funext x; congr; funext b
rw [loop (i := i)]; rw [← ij, Nat.succ_add]; rfl
conv => lhs; simp only [forIn, Array.forIn]
rw [loop (Nat.zero_add _)]; rfl
theorem zipWith_eq_zipWith_data (f : α → β → γ) (as : Array α) (bs : Array β) :
(as.zipWith bs f).data = as.data.zipWith f bs.data := by
let rec loop : ∀ (i : Nat) cs, i ≤ as.size → i ≤ bs.size →
(zipWithAux f as bs i cs).data = cs.data ++ (as.data.drop i).zipWith f (bs.data.drop i) := by
intro i cs hia hib
unfold zipWithAux
by_cases h : i = as.size ∨ i = bs.size
case pos =>
have : ¬(i < as.size) ∨ ¬(i < bs.size) := by
cases h <;> simp_all only [Nat.not_lt, Nat.le_refl, true_or, or_true]
-- Cleaned up aesop output below
simp_all only [Nat.not_lt]
cases h <;> [(cases this); (cases this)]
· simp_all only [Nat.le_refl, Nat.lt_irrefl, dite_false, List.drop_length,
List.zipWith_nil_left, List.append_nil]
· simp_all only [Nat.le_refl, Nat.lt_irrefl, dite_false, List.drop_length,
List.zipWith_nil_left, List.append_nil]
· simp_all only [Nat.le_refl, Nat.lt_irrefl, dite_false, List.drop_length,
List.zipWith_nil_right, List.append_nil]
split <;> simp_all only [Nat.not_lt]
· simp_all only [Nat.le_refl, Nat.lt_irrefl, dite_false, List.drop_length,
List.zipWith_nil_right, List.append_nil]
split <;> simp_all only [Nat.not_lt]
case neg =>
rw [not_or] at h
have has : i < as.size := Nat.lt_of_le_of_ne hia h.1
have hbs : i < bs.size := Nat.lt_of_le_of_ne hib h.2
simp only [has, hbs, dite_true]
rw [loop (i+1) _ has hbs, Array.push_data]
have h₁ : [f as[i] bs[i]] = List.zipWith f [as[i]] [bs[i]] := rfl
let i_as : Fin as.data.length := ⟨i, has⟩
let i_bs : Fin bs.data.length := ⟨i, hbs⟩
rw [h₁, List.append_assoc]
congr
rw [← List.zipWith_append (h := by simp), getElem_eq_data_get, getElem_eq_data_get]
show List.zipWith f ((List.get as.data i_as) :: List.drop (i_as + 1) as.data)
((List.get bs.data i_bs) :: List.drop (i_bs + 1) bs.data) =
List.zipWith f (List.drop i as.data) (List.drop i bs.data)
simp only [List.get_cons_drop]
termination_by as.size - i
simp [zipWith, loop 0 #[] (by simp) (by simp)]
theorem size_zipWith (as : Array α) (bs : Array β) (f : α → β → γ) :
(as.zipWith bs f).size = min as.size bs.size := by
rw [size_eq_length_data, zipWith_eq_zipWith_data, List.length_zipWith]
theorem zip_eq_zip_data (as : Array α) (bs : Array β) :
(as.zip bs).data = as.data.zip bs.data :=
zipWith_eq_zipWith_data Prod.mk as bs
theorem size_zip (as : Array α) (bs : Array β) :
(as.zip bs).size = min as.size bs.size :=
as.size_zipWith bs Prod.mk
theorem size_filter_le (p : α → Bool) (l : Array α) :
(l.filter p).size ≤ l.size := by
simp only [← data_length, filter_data]
apply List.length_filter_le
@[simp] theorem join_data {l : Array (Array α)} : l.join.data = (l.data.map data).join := by
dsimp [join]
simp only [foldl_eq_foldl_data]
generalize l.data = l
have : ∀ a : Array α, (List.foldl ?_ a l).data = a.data ++ ?_ := ?_
exact this #[]
induction l with
| nil => simp
| cons h => induction h.data <;> simp [*]
theorem mem_join : ∀ {L : Array (Array α)}, a ∈ L.join ↔ ∃ l, l ∈ L ∧ a ∈ l := by
simp only [mem_def, join_data, List.mem_join, List.mem_map]
intro l
constructor
· rintro ⟨_, ⟨s, m, rfl⟩, h⟩
exact ⟨s, m, h⟩
· rintro ⟨s, h₁, h₂⟩
refine ⟨s.data, ⟨⟨s, h₁, rfl⟩, h₂⟩⟩
@[simp] proof_wanted erase_data [BEq α] {l : Array α} {a : α} : (l.erase a).data = l.data.erase a
| .lake/packages/batteries/Batteries/Data/Array/Lemmas.lean | 121 | 125 | theorem size_shrink_loop (a : Array α) (n) : (shrink.loop n a).size = a.size - n := by |
induction n generalizing a with simp[shrink.loop]
| succ n ih =>
simp[ih]
omega
|
import Mathlib.Dynamics.Ergodic.MeasurePreserving
import Mathlib.MeasureTheory.Function.SimpleFunc
import Mathlib.MeasureTheory.Measure.MutuallySingular
import Mathlib.MeasureTheory.Measure.Count
import Mathlib.Topology.IndicatorConstPointwise
import Mathlib.MeasureTheory.Constructions.BorelSpace.Real
#align_import measure_theory.integral.lebesgue from "leanprover-community/mathlib"@"c14c8fcde993801fca8946b0d80131a1a81d1520"
assert_not_exists NormedSpace
set_option autoImplicit true
noncomputable section
open Set hiding restrict restrict_apply
open Filter ENNReal
open Function (support)
open scoped Classical
open Topology NNReal ENNReal MeasureTheory
namespace MeasureTheory
local infixr:25 " →ₛ " => SimpleFunc
variable {α β γ δ : Type*}
section Lintegral
open SimpleFunc
variable {m : MeasurableSpace α} {μ ν : Measure α}
irreducible_def lintegral {_ : MeasurableSpace α} (μ : Measure α) (f : α → ℝ≥0∞) : ℝ≥0∞ :=
⨆ (g : α →ₛ ℝ≥0∞) (_ : ⇑g ≤ f), g.lintegral μ
#align measure_theory.lintegral MeasureTheory.lintegral
@[inherit_doc MeasureTheory.lintegral]
notation3 "∫⁻ "(...)", "r:60:(scoped f => f)" ∂"μ:70 => lintegral μ r
@[inherit_doc MeasureTheory.lintegral]
notation3 "∫⁻ "(...)", "r:60:(scoped f => lintegral volume f) => r
@[inherit_doc MeasureTheory.lintegral]
notation3"∫⁻ "(...)" in "s", "r:60:(scoped f => f)" ∂"μ:70 => lintegral (Measure.restrict μ s) r
@[inherit_doc MeasureTheory.lintegral]
notation3"∫⁻ "(...)" in "s", "r:60:(scoped f => lintegral (Measure.restrict volume s) f) => r
theorem SimpleFunc.lintegral_eq_lintegral {m : MeasurableSpace α} (f : α →ₛ ℝ≥0∞) (μ : Measure α) :
∫⁻ a, f a ∂μ = f.lintegral μ := by
rw [MeasureTheory.lintegral]
exact le_antisymm (iSup₂_le fun g hg => lintegral_mono hg <| le_rfl)
(le_iSup₂_of_le f le_rfl le_rfl)
#align measure_theory.simple_func.lintegral_eq_lintegral MeasureTheory.SimpleFunc.lintegral_eq_lintegral
@[mono]
theorem lintegral_mono' {m : MeasurableSpace α} ⦃μ ν : Measure α⦄ (hμν : μ ≤ ν) ⦃f g : α → ℝ≥0∞⦄
(hfg : f ≤ g) : ∫⁻ a, f a ∂μ ≤ ∫⁻ a, g a ∂ν := by
rw [lintegral, lintegral]
exact iSup_mono fun φ => iSup_mono' fun hφ => ⟨le_trans hφ hfg, lintegral_mono (le_refl φ) hμν⟩
#align measure_theory.lintegral_mono' MeasureTheory.lintegral_mono'
-- workaround for the known eta-reduction issue with `@[gcongr]`
@[gcongr] theorem lintegral_mono_fn' ⦃f g : α → ℝ≥0∞⦄ (hfg : ∀ x, f x ≤ g x) (h2 : μ ≤ ν) :
lintegral μ f ≤ lintegral ν g :=
lintegral_mono' h2 hfg
theorem lintegral_mono ⦃f g : α → ℝ≥0∞⦄ (hfg : f ≤ g) : ∫⁻ a, f a ∂μ ≤ ∫⁻ a, g a ∂μ :=
lintegral_mono' (le_refl μ) hfg
#align measure_theory.lintegral_mono MeasureTheory.lintegral_mono
-- workaround for the known eta-reduction issue with `@[gcongr]`
@[gcongr] theorem lintegral_mono_fn ⦃f g : α → ℝ≥0∞⦄ (hfg : ∀ x, f x ≤ g x) :
lintegral μ f ≤ lintegral μ g :=
lintegral_mono hfg
theorem lintegral_mono_nnreal {f g : α → ℝ≥0} (h : f ≤ g) : ∫⁻ a, f a ∂μ ≤ ∫⁻ a, g a ∂μ :=
lintegral_mono fun a => ENNReal.coe_le_coe.2 (h a)
#align measure_theory.lintegral_mono_nnreal MeasureTheory.lintegral_mono_nnreal
theorem iSup_lintegral_measurable_le_eq_lintegral (f : α → ℝ≥0∞) :
⨆ (g : α → ℝ≥0∞) (_ : Measurable g) (_ : g ≤ f), ∫⁻ a, g a ∂μ = ∫⁻ a, f a ∂μ := by
apply le_antisymm
· exact iSup_le fun i => iSup_le fun _ => iSup_le fun h'i => lintegral_mono h'i
· rw [lintegral]
refine iSup₂_le fun i hi => le_iSup₂_of_le i i.measurable <| le_iSup_of_le hi ?_
exact le_of_eq (i.lintegral_eq_lintegral _).symm
#align measure_theory.supr_lintegral_measurable_le_eq_lintegral MeasureTheory.iSup_lintegral_measurable_le_eq_lintegral
theorem lintegral_mono_set {_ : MeasurableSpace α} ⦃μ : Measure α⦄ {s t : Set α} {f : α → ℝ≥0∞}
(hst : s ⊆ t) : ∫⁻ x in s, f x ∂μ ≤ ∫⁻ x in t, f x ∂μ :=
lintegral_mono' (Measure.restrict_mono hst (le_refl μ)) (le_refl f)
#align measure_theory.lintegral_mono_set MeasureTheory.lintegral_mono_set
theorem lintegral_mono_set' {_ : MeasurableSpace α} ⦃μ : Measure α⦄ {s t : Set α} {f : α → ℝ≥0∞}
(hst : s ≤ᵐ[μ] t) : ∫⁻ x in s, f x ∂μ ≤ ∫⁻ x in t, f x ∂μ :=
lintegral_mono' (Measure.restrict_mono' hst (le_refl μ)) (le_refl f)
#align measure_theory.lintegral_mono_set' MeasureTheory.lintegral_mono_set'
theorem monotone_lintegral {_ : MeasurableSpace α} (μ : Measure α) : Monotone (lintegral μ) :=
lintegral_mono
#align measure_theory.monotone_lintegral MeasureTheory.monotone_lintegral
@[simp]
theorem lintegral_const (c : ℝ≥0∞) : ∫⁻ _, c ∂μ = c * μ univ := by
rw [← SimpleFunc.const_lintegral, ← SimpleFunc.lintegral_eq_lintegral, SimpleFunc.coe_const]
rfl
#align measure_theory.lintegral_const MeasureTheory.lintegral_const
theorem lintegral_zero : ∫⁻ _ : α, 0 ∂μ = 0 := by simp
#align measure_theory.lintegral_zero MeasureTheory.lintegral_zero
theorem lintegral_zero_fun : lintegral μ (0 : α → ℝ≥0∞) = 0 :=
lintegral_zero
#align measure_theory.lintegral_zero_fun MeasureTheory.lintegral_zero_fun
-- @[simp] -- Porting note (#10618): simp can prove this
theorem lintegral_one : ∫⁻ _, (1 : ℝ≥0∞) ∂μ = μ univ := by rw [lintegral_const, one_mul]
#align measure_theory.lintegral_one MeasureTheory.lintegral_one
theorem set_lintegral_const (s : Set α) (c : ℝ≥0∞) : ∫⁻ _ in s, c ∂μ = c * μ s := by
rw [lintegral_const, Measure.restrict_apply_univ]
#align measure_theory.set_lintegral_const MeasureTheory.set_lintegral_const
theorem set_lintegral_one (s) : ∫⁻ _ in s, 1 ∂μ = μ s := by rw [set_lintegral_const, one_mul]
#align measure_theory.set_lintegral_one MeasureTheory.set_lintegral_one
theorem set_lintegral_const_lt_top [IsFiniteMeasure μ] (s : Set α) {c : ℝ≥0∞} (hc : c ≠ ∞) :
∫⁻ _ in s, c ∂μ < ∞ := by
rw [lintegral_const]
exact ENNReal.mul_lt_top hc (measure_ne_top (μ.restrict s) univ)
#align measure_theory.set_lintegral_const_lt_top MeasureTheory.set_lintegral_const_lt_top
theorem lintegral_const_lt_top [IsFiniteMeasure μ] {c : ℝ≥0∞} (hc : c ≠ ∞) : ∫⁻ _, c ∂μ < ∞ := by
simpa only [Measure.restrict_univ] using set_lintegral_const_lt_top (univ : Set α) hc
#align measure_theory.lintegral_const_lt_top MeasureTheory.lintegral_const_lt_top
section
variable (μ)
theorem exists_measurable_le_lintegral_eq (f : α → ℝ≥0∞) :
∃ g : α → ℝ≥0∞, Measurable g ∧ g ≤ f ∧ ∫⁻ a, f a ∂μ = ∫⁻ a, g a ∂μ := by
rcases eq_or_ne (∫⁻ a, f a ∂μ) 0 with h₀ | h₀
· exact ⟨0, measurable_zero, zero_le f, h₀.trans lintegral_zero.symm⟩
rcases exists_seq_strictMono_tendsto' h₀.bot_lt with ⟨L, _, hLf, hL_tendsto⟩
have : ∀ n, ∃ g : α → ℝ≥0∞, Measurable g ∧ g ≤ f ∧ L n < ∫⁻ a, g a ∂μ := by
intro n
simpa only [← iSup_lintegral_measurable_le_eq_lintegral f, lt_iSup_iff, exists_prop] using
(hLf n).2
choose g hgm hgf hLg using this
refine
⟨fun x => ⨆ n, g n x, measurable_iSup hgm, fun x => iSup_le fun n => hgf n x, le_antisymm ?_ ?_⟩
· refine le_of_tendsto' hL_tendsto fun n => (hLg n).le.trans <| lintegral_mono fun x => ?_
exact le_iSup (fun n => g n x) n
· exact lintegral_mono fun x => iSup_le fun n => hgf n x
#align measure_theory.exists_measurable_le_lintegral_eq MeasureTheory.exists_measurable_le_lintegral_eq
end
theorem lintegral_eq_nnreal {m : MeasurableSpace α} (f : α → ℝ≥0∞) (μ : Measure α) :
∫⁻ a, f a ∂μ =
⨆ (φ : α →ₛ ℝ≥0) (_ : ∀ x, ↑(φ x) ≤ f x), (φ.map ((↑) : ℝ≥0 → ℝ≥0∞)).lintegral μ := by
rw [lintegral]
refine
le_antisymm (iSup₂_le fun φ hφ => ?_) (iSup_mono' fun φ => ⟨φ.map ((↑) : ℝ≥0 → ℝ≥0∞), le_rfl⟩)
by_cases h : ∀ᵐ a ∂μ, φ a ≠ ∞
· let ψ := φ.map ENNReal.toNNReal
replace h : ψ.map ((↑) : ℝ≥0 → ℝ≥0∞) =ᵐ[μ] φ := h.mono fun a => ENNReal.coe_toNNReal
have : ∀ x, ↑(ψ x) ≤ f x := fun x => le_trans ENNReal.coe_toNNReal_le_self (hφ x)
exact
le_iSup_of_le (φ.map ENNReal.toNNReal) (le_iSup_of_le this (ge_of_eq <| lintegral_congr h))
· have h_meas : μ (φ ⁻¹' {∞}) ≠ 0 := mt measure_zero_iff_ae_nmem.1 h
refine le_trans le_top (ge_of_eq <| (iSup_eq_top _).2 fun b hb => ?_)
obtain ⟨n, hn⟩ : ∃ n : ℕ, b < n * μ (φ ⁻¹' {∞}) := exists_nat_mul_gt h_meas (ne_of_lt hb)
use (const α (n : ℝ≥0)).restrict (φ ⁻¹' {∞})
simp only [lt_iSup_iff, exists_prop, coe_restrict, φ.measurableSet_preimage, coe_const,
ENNReal.coe_indicator, map_coe_ennreal_restrict, SimpleFunc.map_const, ENNReal.coe_natCast,
restrict_const_lintegral]
refine ⟨indicator_le fun x hx => le_trans ?_ (hφ _), hn⟩
simp only [mem_preimage, mem_singleton_iff] at hx
simp only [hx, le_top]
#align measure_theory.lintegral_eq_nnreal MeasureTheory.lintegral_eq_nnreal
theorem exists_simpleFunc_forall_lintegral_sub_lt_of_pos {f : α → ℝ≥0∞} (h : ∫⁻ x, f x ∂μ ≠ ∞)
{ε : ℝ≥0∞} (hε : ε ≠ 0) :
∃ φ : α →ₛ ℝ≥0,
(∀ x, ↑(φ x) ≤ f x) ∧
∀ ψ : α →ₛ ℝ≥0, (∀ x, ↑(ψ x) ≤ f x) → (map (↑) (ψ - φ)).lintegral μ < ε := by
rw [lintegral_eq_nnreal] at h
have := ENNReal.lt_add_right h hε
erw [ENNReal.biSup_add] at this <;> [skip; exact ⟨0, fun x => zero_le _⟩]
simp_rw [lt_iSup_iff, iSup_lt_iff, iSup_le_iff] at this
rcases this with ⟨φ, hle : ∀ x, ↑(φ x) ≤ f x, b, hbφ, hb⟩
refine ⟨φ, hle, fun ψ hψ => ?_⟩
have : (map (↑) φ).lintegral μ ≠ ∞ := ne_top_of_le_ne_top h (by exact le_iSup₂ (α := ℝ≥0∞) φ hle)
rw [← ENNReal.add_lt_add_iff_left this, ← add_lintegral, ← SimpleFunc.map_add @ENNReal.coe_add]
refine (hb _ fun x => le_trans ?_ (max_le (hle x) (hψ x))).trans_lt hbφ
norm_cast
simp only [add_apply, sub_apply, add_tsub_eq_max]
rfl
#align measure_theory.exists_simple_func_forall_lintegral_sub_lt_of_pos MeasureTheory.exists_simpleFunc_forall_lintegral_sub_lt_of_pos
theorem iSup_lintegral_le {ι : Sort*} (f : ι → α → ℝ≥0∞) :
⨆ i, ∫⁻ a, f i a ∂μ ≤ ∫⁻ a, ⨆ i, f i a ∂μ := by
simp only [← iSup_apply]
exact (monotone_lintegral μ).le_map_iSup
#align measure_theory.supr_lintegral_le MeasureTheory.iSup_lintegral_le
theorem iSup₂_lintegral_le {ι : Sort*} {ι' : ι → Sort*} (f : ∀ i, ι' i → α → ℝ≥0∞) :
⨆ (i) (j), ∫⁻ a, f i j a ∂μ ≤ ∫⁻ a, ⨆ (i) (j), f i j a ∂μ := by
convert (monotone_lintegral μ).le_map_iSup₂ f with a
simp only [iSup_apply]
#align measure_theory.supr₂_lintegral_le MeasureTheory.iSup₂_lintegral_le
theorem le_iInf_lintegral {ι : Sort*} (f : ι → α → ℝ≥0∞) :
∫⁻ a, ⨅ i, f i a ∂μ ≤ ⨅ i, ∫⁻ a, f i a ∂μ := by
simp only [← iInf_apply]
exact (monotone_lintegral μ).map_iInf_le
#align measure_theory.le_infi_lintegral MeasureTheory.le_iInf_lintegral
theorem le_iInf₂_lintegral {ι : Sort*} {ι' : ι → Sort*} (f : ∀ i, ι' i → α → ℝ≥0∞) :
∫⁻ a, ⨅ (i) (h : ι' i), f i h a ∂μ ≤ ⨅ (i) (h : ι' i), ∫⁻ a, f i h a ∂μ := by
convert (monotone_lintegral μ).map_iInf₂_le f with a
simp only [iInf_apply]
#align measure_theory.le_infi₂_lintegral MeasureTheory.le_iInf₂_lintegral
theorem lintegral_mono_ae {f g : α → ℝ≥0∞} (h : ∀ᵐ a ∂μ, f a ≤ g a) :
∫⁻ a, f a ∂μ ≤ ∫⁻ a, g a ∂μ := by
rcases exists_measurable_superset_of_null h with ⟨t, hts, ht, ht0⟩
have : ∀ᵐ x ∂μ, x ∉ t := measure_zero_iff_ae_nmem.1 ht0
rw [lintegral, lintegral]
refine iSup_le fun s => iSup_le fun hfs => le_iSup_of_le (s.restrict tᶜ) <| le_iSup_of_le ?_ ?_
· intro a
by_cases h : a ∈ t <;>
simp only [restrict_apply s ht.compl, mem_compl_iff, h, not_true, not_false_eq_true,
indicator_of_not_mem, zero_le, not_false_eq_true, indicator_of_mem]
exact le_trans (hfs a) (_root_.by_contradiction fun hnfg => h (hts hnfg))
· refine le_of_eq (SimpleFunc.lintegral_congr <| this.mono fun a hnt => ?_)
by_cases hat : a ∈ t <;> simp only [restrict_apply s ht.compl, mem_compl_iff, hat, not_true,
not_false_eq_true, indicator_of_not_mem, not_false_eq_true, indicator_of_mem]
exact (hnt hat).elim
#align measure_theory.lintegral_mono_ae MeasureTheory.lintegral_mono_ae
theorem set_lintegral_mono_ae {s : Set α} {f g : α → ℝ≥0∞} (hf : Measurable f) (hg : Measurable g)
(hfg : ∀ᵐ x ∂μ, x ∈ s → f x ≤ g x) : ∫⁻ x in s, f x ∂μ ≤ ∫⁻ x in s, g x ∂μ :=
lintegral_mono_ae <| (ae_restrict_iff <| measurableSet_le hf hg).2 hfg
#align measure_theory.set_lintegral_mono_ae MeasureTheory.set_lintegral_mono_ae
theorem set_lintegral_mono {s : Set α} {f g : α → ℝ≥0∞} (hf : Measurable f) (hg : Measurable g)
(hfg : ∀ x ∈ s, f x ≤ g x) : ∫⁻ x in s, f x ∂μ ≤ ∫⁻ x in s, g x ∂μ :=
set_lintegral_mono_ae hf hg (ae_of_all _ hfg)
#align measure_theory.set_lintegral_mono MeasureTheory.set_lintegral_mono
theorem set_lintegral_mono_ae' {s : Set α} {f g : α → ℝ≥0∞} (hs : MeasurableSet s)
(hfg : ∀ᵐ x ∂μ, x ∈ s → f x ≤ g x) : ∫⁻ x in s, f x ∂μ ≤ ∫⁻ x in s, g x ∂μ :=
lintegral_mono_ae <| (ae_restrict_iff' hs).2 hfg
theorem set_lintegral_mono' {s : Set α} {f g : α → ℝ≥0∞} (hs : MeasurableSet s)
(hfg : ∀ x ∈ s, f x ≤ g x) : ∫⁻ x in s, f x ∂μ ≤ ∫⁻ x in s, g x ∂μ :=
set_lintegral_mono_ae' hs (ae_of_all _ hfg)
theorem set_lintegral_le_lintegral (s : Set α) (f : α → ℝ≥0∞) :
∫⁻ x in s, f x ∂μ ≤ ∫⁻ x, f x ∂μ :=
lintegral_mono' Measure.restrict_le_self le_rfl
theorem lintegral_congr_ae {f g : α → ℝ≥0∞} (h : f =ᵐ[μ] g) : ∫⁻ a, f a ∂μ = ∫⁻ a, g a ∂μ :=
le_antisymm (lintegral_mono_ae <| h.le) (lintegral_mono_ae <| h.symm.le)
#align measure_theory.lintegral_congr_ae MeasureTheory.lintegral_congr_ae
theorem lintegral_congr {f g : α → ℝ≥0∞} (h : ∀ a, f a = g a) : ∫⁻ a, f a ∂μ = ∫⁻ a, g a ∂μ := by
simp only [h]
#align measure_theory.lintegral_congr MeasureTheory.lintegral_congr
theorem set_lintegral_congr {f : α → ℝ≥0∞} {s t : Set α} (h : s =ᵐ[μ] t) :
∫⁻ x in s, f x ∂μ = ∫⁻ x in t, f x ∂μ := by rw [Measure.restrict_congr_set h]
#align measure_theory.set_lintegral_congr MeasureTheory.set_lintegral_congr
theorem set_lintegral_congr_fun {f g : α → ℝ≥0∞} {s : Set α} (hs : MeasurableSet s)
(hfg : ∀ᵐ x ∂μ, x ∈ s → f x = g x) : ∫⁻ x in s, f x ∂μ = ∫⁻ x in s, g x ∂μ := by
rw [lintegral_congr_ae]
rw [EventuallyEq]
rwa [ae_restrict_iff' hs]
#align measure_theory.set_lintegral_congr_fun MeasureTheory.set_lintegral_congr_fun
theorem lintegral_ofReal_le_lintegral_nnnorm (f : α → ℝ) :
∫⁻ x, ENNReal.ofReal (f x) ∂μ ≤ ∫⁻ x, ‖f x‖₊ ∂μ := by
simp_rw [← ofReal_norm_eq_coe_nnnorm]
refine lintegral_mono fun x => ENNReal.ofReal_le_ofReal ?_
rw [Real.norm_eq_abs]
exact le_abs_self (f x)
#align measure_theory.lintegral_of_real_le_lintegral_nnnorm MeasureTheory.lintegral_ofReal_le_lintegral_nnnorm
theorem lintegral_nnnorm_eq_of_ae_nonneg {f : α → ℝ} (h_nonneg : 0 ≤ᵐ[μ] f) :
∫⁻ x, ‖f x‖₊ ∂μ = ∫⁻ x, ENNReal.ofReal (f x) ∂μ := by
apply lintegral_congr_ae
filter_upwards [h_nonneg] with x hx
rw [Real.nnnorm_of_nonneg hx, ENNReal.ofReal_eq_coe_nnreal hx]
#align measure_theory.lintegral_nnnorm_eq_of_ae_nonneg MeasureTheory.lintegral_nnnorm_eq_of_ae_nonneg
theorem lintegral_nnnorm_eq_of_nonneg {f : α → ℝ} (h_nonneg : 0 ≤ f) :
∫⁻ x, ‖f x‖₊ ∂μ = ∫⁻ x, ENNReal.ofReal (f x) ∂μ :=
lintegral_nnnorm_eq_of_ae_nonneg (Filter.eventually_of_forall h_nonneg)
#align measure_theory.lintegral_nnnorm_eq_of_nonneg MeasureTheory.lintegral_nnnorm_eq_of_nonneg
theorem lintegral_iSup {f : ℕ → α → ℝ≥0∞} (hf : ∀ n, Measurable (f n)) (h_mono : Monotone f) :
∫⁻ a, ⨆ n, f n a ∂μ = ⨆ n, ∫⁻ a, f n a ∂μ := by
set c : ℝ≥0 → ℝ≥0∞ := (↑)
set F := fun a : α => ⨆ n, f n a
refine le_antisymm ?_ (iSup_lintegral_le _)
rw [lintegral_eq_nnreal]
refine iSup_le fun s => iSup_le fun hsf => ?_
refine ENNReal.le_of_forall_lt_one_mul_le fun a ha => ?_
rcases ENNReal.lt_iff_exists_coe.1 ha with ⟨r, rfl, _⟩
have ha : r < 1 := ENNReal.coe_lt_coe.1 ha
let rs := s.map fun a => r * a
have eq_rs : rs.map c = (const α r : α →ₛ ℝ≥0∞) * map c s := rfl
have eq : ∀ p, rs.map c ⁻¹' {p} = ⋃ n, rs.map c ⁻¹' {p} ∩ { a | p ≤ f n a } := by
intro p
rw [← inter_iUnion]; nth_rw 1 [← inter_univ (map c rs ⁻¹' {p})]
refine Set.ext fun x => and_congr_right fun hx => true_iff_iff.2 ?_
by_cases p_eq : p = 0
· simp [p_eq]
simp only [coe_map, mem_preimage, Function.comp_apply, mem_singleton_iff] at hx
subst hx
have : r * s x ≠ 0 := by rwa [Ne, ← ENNReal.coe_eq_zero]
have : s x ≠ 0 := right_ne_zero_of_mul this
have : (rs.map c) x < ⨆ n : ℕ, f n x := by
refine lt_of_lt_of_le (ENNReal.coe_lt_coe.2 ?_) (hsf x)
suffices r * s x < 1 * s x by simpa
exact mul_lt_mul_of_pos_right ha (pos_iff_ne_zero.2 this)
rcases lt_iSup_iff.1 this with ⟨i, hi⟩
exact mem_iUnion.2 ⟨i, le_of_lt hi⟩
have mono : ∀ r : ℝ≥0∞, Monotone fun n => rs.map c ⁻¹' {r} ∩ { a | r ≤ f n a } := by
intro r i j h
refine inter_subset_inter_right _ ?_
simp_rw [subset_def, mem_setOf]
intro x hx
exact le_trans hx (h_mono h x)
have h_meas : ∀ n, MeasurableSet {a : α | map c rs a ≤ f n a} := fun n =>
measurableSet_le (SimpleFunc.measurable _) (hf n)
calc
(r : ℝ≥0∞) * (s.map c).lintegral μ = ∑ r ∈ (rs.map c).range, r * μ (rs.map c ⁻¹' {r}) := by
rw [← const_mul_lintegral, eq_rs, SimpleFunc.lintegral]
_ = ∑ r ∈ (rs.map c).range, r * μ (⋃ n, rs.map c ⁻¹' {r} ∩ { a | r ≤ f n a }) := by
simp only [(eq _).symm]
_ = ∑ r ∈ (rs.map c).range, ⨆ n, r * μ (rs.map c ⁻¹' {r} ∩ { a | r ≤ f n a }) :=
(Finset.sum_congr rfl fun x _ => by
rw [measure_iUnion_eq_iSup (mono x).directed_le, ENNReal.mul_iSup])
_ = ⨆ n, ∑ r ∈ (rs.map c).range, r * μ (rs.map c ⁻¹' {r} ∩ { a | r ≤ f n a }) := by
refine ENNReal.finset_sum_iSup_nat fun p i j h ↦ ?_
gcongr _ * μ ?_
exact mono p h
_ ≤ ⨆ n : ℕ, ((rs.map c).restrict { a | (rs.map c) a ≤ f n a }).lintegral μ := by
gcongr with n
rw [restrict_lintegral _ (h_meas n)]
refine le_of_eq (Finset.sum_congr rfl fun r _ => ?_)
congr 2 with a
refine and_congr_right ?_
simp (config := { contextual := true })
_ ≤ ⨆ n, ∫⁻ a, f n a ∂μ := by
simp only [← SimpleFunc.lintegral_eq_lintegral]
gcongr with n a
simp only [map_apply] at h_meas
simp only [coe_map, restrict_apply _ (h_meas _), (· ∘ ·)]
exact indicator_apply_le id
#align measure_theory.lintegral_supr MeasureTheory.lintegral_iSup
theorem lintegral_iSup' {f : ℕ → α → ℝ≥0∞} (hf : ∀ n, AEMeasurable (f n) μ)
(h_mono : ∀ᵐ x ∂μ, Monotone fun n => f n x) : ∫⁻ a, ⨆ n, f n a ∂μ = ⨆ n, ∫⁻ a, f n a ∂μ := by
simp_rw [← iSup_apply]
let p : α → (ℕ → ℝ≥0∞) → Prop := fun _ f' => Monotone f'
have hp : ∀ᵐ x ∂μ, p x fun i => f i x := h_mono
have h_ae_seq_mono : Monotone (aeSeq hf p) := by
intro n m hnm x
by_cases hx : x ∈ aeSeqSet hf p
· exact aeSeq.prop_of_mem_aeSeqSet hf hx hnm
· simp only [aeSeq, hx, if_false, le_rfl]
rw [lintegral_congr_ae (aeSeq.iSup hf hp).symm]
simp_rw [iSup_apply]
rw [lintegral_iSup (aeSeq.measurable hf p) h_ae_seq_mono]
congr with n
exact lintegral_congr_ae (aeSeq.aeSeq_n_eq_fun_n_ae hf hp n)
#align measure_theory.lintegral_supr' MeasureTheory.lintegral_iSup'
theorem lintegral_tendsto_of_tendsto_of_monotone {f : ℕ → α → ℝ≥0∞} {F : α → ℝ≥0∞}
(hf : ∀ n, AEMeasurable (f n) μ) (h_mono : ∀ᵐ x ∂μ, Monotone fun n => f n x)
(h_tendsto : ∀ᵐ x ∂μ, Tendsto (fun n => f n x) atTop (𝓝 <| F x)) :
Tendsto (fun n => ∫⁻ x, f n x ∂μ) atTop (𝓝 <| ∫⁻ x, F x ∂μ) := by
have : Monotone fun n => ∫⁻ x, f n x ∂μ := fun i j hij =>
lintegral_mono_ae (h_mono.mono fun x hx => hx hij)
suffices key : ∫⁻ x, F x ∂μ = ⨆ n, ∫⁻ x, f n x ∂μ by
rw [key]
exact tendsto_atTop_iSup this
rw [← lintegral_iSup' hf h_mono]
refine lintegral_congr_ae ?_
filter_upwards [h_mono, h_tendsto] with _ hx_mono hx_tendsto using
tendsto_nhds_unique hx_tendsto (tendsto_atTop_iSup hx_mono)
#align measure_theory.lintegral_tendsto_of_tendsto_of_monotone MeasureTheory.lintegral_tendsto_of_tendsto_of_monotone
theorem lintegral_eq_iSup_eapprox_lintegral {f : α → ℝ≥0∞} (hf : Measurable f) :
∫⁻ a, f a ∂μ = ⨆ n, (eapprox f n).lintegral μ :=
calc
∫⁻ a, f a ∂μ = ∫⁻ a, ⨆ n, (eapprox f n : α → ℝ≥0∞) a ∂μ := by
congr; ext a; rw [iSup_eapprox_apply f hf]
_ = ⨆ n, ∫⁻ a, (eapprox f n : α → ℝ≥0∞) a ∂μ := by
apply lintegral_iSup
· measurability
· intro i j h
exact monotone_eapprox f h
_ = ⨆ n, (eapprox f n).lintegral μ := by
congr; ext n; rw [(eapprox f n).lintegral_eq_lintegral]
#align measure_theory.lintegral_eq_supr_eapprox_lintegral MeasureTheory.lintegral_eq_iSup_eapprox_lintegral
theorem exists_pos_set_lintegral_lt_of_measure_lt {f : α → ℝ≥0∞} (h : ∫⁻ x, f x ∂μ ≠ ∞) {ε : ℝ≥0∞}
(hε : ε ≠ 0) : ∃ δ > 0, ∀ s, μ s < δ → ∫⁻ x in s, f x ∂μ < ε := by
rcases exists_between (pos_iff_ne_zero.mpr hε) with ⟨ε₂, hε₂0, hε₂ε⟩
rcases exists_between hε₂0 with ⟨ε₁, hε₁0, hε₁₂⟩
rcases exists_simpleFunc_forall_lintegral_sub_lt_of_pos h hε₁0.ne' with ⟨φ, _, hφ⟩
rcases φ.exists_forall_le with ⟨C, hC⟩
use (ε₂ - ε₁) / C, ENNReal.div_pos_iff.2 ⟨(tsub_pos_iff_lt.2 hε₁₂).ne', ENNReal.coe_ne_top⟩
refine fun s hs => lt_of_le_of_lt ?_ hε₂ε
simp only [lintegral_eq_nnreal, iSup_le_iff]
intro ψ hψ
calc
(map (↑) ψ).lintegral (μ.restrict s) ≤
(map (↑) φ).lintegral (μ.restrict s) + (map (↑) (ψ - φ)).lintegral (μ.restrict s) := by
rw [← SimpleFunc.add_lintegral, ← SimpleFunc.map_add @ENNReal.coe_add]
refine SimpleFunc.lintegral_mono (fun x => ?_) le_rfl
simp only [add_tsub_eq_max, le_max_right, coe_map, Function.comp_apply, SimpleFunc.coe_add,
SimpleFunc.coe_sub, Pi.add_apply, Pi.sub_apply, ENNReal.coe_max (φ x) (ψ x)]
_ ≤ (map (↑) φ).lintegral (μ.restrict s) + ε₁ := by
gcongr
refine le_trans ?_ (hφ _ hψ).le
exact SimpleFunc.lintegral_mono le_rfl Measure.restrict_le_self
_ ≤ (SimpleFunc.const α (C : ℝ≥0∞)).lintegral (μ.restrict s) + ε₁ := by
gcongr
exact SimpleFunc.lintegral_mono (fun x ↦ ENNReal.coe_le_coe.2 (hC x)) le_rfl
_ = C * μ s + ε₁ := by
simp only [← SimpleFunc.lintegral_eq_lintegral, coe_const, lintegral_const,
Measure.restrict_apply, MeasurableSet.univ, univ_inter, Function.const]
_ ≤ C * ((ε₂ - ε₁) / C) + ε₁ := by gcongr
_ ≤ ε₂ - ε₁ + ε₁ := by gcongr; apply mul_div_le
_ = ε₂ := tsub_add_cancel_of_le hε₁₂.le
#align measure_theory.exists_pos_set_lintegral_lt_of_measure_lt MeasureTheory.exists_pos_set_lintegral_lt_of_measure_lt
theorem tendsto_set_lintegral_zero {ι} {f : α → ℝ≥0∞} (h : ∫⁻ x, f x ∂μ ≠ ∞) {l : Filter ι}
{s : ι → Set α} (hl : Tendsto (μ ∘ s) l (𝓝 0)) :
Tendsto (fun i => ∫⁻ x in s i, f x ∂μ) l (𝓝 0) := by
simp only [ENNReal.nhds_zero, tendsto_iInf, tendsto_principal, mem_Iio,
← pos_iff_ne_zero] at hl ⊢
intro ε ε0
rcases exists_pos_set_lintegral_lt_of_measure_lt h ε0.ne' with ⟨δ, δ0, hδ⟩
exact (hl δ δ0).mono fun i => hδ _
#align measure_theory.tendsto_set_lintegral_zero MeasureTheory.tendsto_set_lintegral_zero
theorem le_lintegral_add (f g : α → ℝ≥0∞) :
∫⁻ a, f a ∂μ + ∫⁻ a, g a ∂μ ≤ ∫⁻ a, f a + g a ∂μ := by
simp only [lintegral]
refine ENNReal.biSup_add_biSup_le' (p := fun h : α →ₛ ℝ≥0∞ => h ≤ f)
(q := fun h : α →ₛ ℝ≥0∞ => h ≤ g) ⟨0, zero_le f⟩ ⟨0, zero_le g⟩ fun f' hf' g' hg' => ?_
exact le_iSup₂_of_le (f' + g') (add_le_add hf' hg') (add_lintegral _ _).ge
#align measure_theory.le_lintegral_add MeasureTheory.le_lintegral_add
-- Use stronger lemmas `lintegral_add_left`/`lintegral_add_right` instead
theorem lintegral_add_aux {f g : α → ℝ≥0∞} (hf : Measurable f) (hg : Measurable g) :
∫⁻ a, f a + g a ∂μ = ∫⁻ a, f a ∂μ + ∫⁻ a, g a ∂μ :=
calc
∫⁻ a, f a + g a ∂μ =
∫⁻ a, (⨆ n, (eapprox f n : α → ℝ≥0∞) a) + ⨆ n, (eapprox g n : α → ℝ≥0∞) a ∂μ := by
simp only [iSup_eapprox_apply, hf, hg]
_ = ∫⁻ a, ⨆ n, (eapprox f n + eapprox g n : α → ℝ≥0∞) a ∂μ := by
congr; funext a
rw [ENNReal.iSup_add_iSup_of_monotone]
· simp only [Pi.add_apply]
· intro i j h
exact monotone_eapprox _ h a
· intro i j h
exact monotone_eapprox _ h a
_ = ⨆ n, (eapprox f n).lintegral μ + (eapprox g n).lintegral μ := by
rw [lintegral_iSup]
· congr
funext n
rw [← SimpleFunc.add_lintegral, ← SimpleFunc.lintegral_eq_lintegral]
simp only [Pi.add_apply, SimpleFunc.coe_add]
· measurability
· intro i j h a
dsimp
gcongr <;> exact monotone_eapprox _ h _
_ = (⨆ n, (eapprox f n).lintegral μ) + ⨆ n, (eapprox g n).lintegral μ := by
refine (ENNReal.iSup_add_iSup_of_monotone ?_ ?_).symm <;>
· intro i j h
exact SimpleFunc.lintegral_mono (monotone_eapprox _ h) le_rfl
_ = ∫⁻ a, f a ∂μ + ∫⁻ a, g a ∂μ := by
rw [lintegral_eq_iSup_eapprox_lintegral hf, lintegral_eq_iSup_eapprox_lintegral hg]
#align measure_theory.lintegral_add_aux MeasureTheory.lintegral_add_aux
@[simp]
theorem lintegral_add_left {f : α → ℝ≥0∞} (hf : Measurable f) (g : α → ℝ≥0∞) :
∫⁻ a, f a + g a ∂μ = ∫⁻ a, f a ∂μ + ∫⁻ a, g a ∂μ := by
refine le_antisymm ?_ (le_lintegral_add _ _)
rcases exists_measurable_le_lintegral_eq μ fun a => f a + g a with ⟨φ, hφm, hφ_le, hφ_eq⟩
calc
∫⁻ a, f a + g a ∂μ = ∫⁻ a, φ a ∂μ := hφ_eq
_ ≤ ∫⁻ a, f a + (φ a - f a) ∂μ := lintegral_mono fun a => le_add_tsub
_ = ∫⁻ a, f a ∂μ + ∫⁻ a, φ a - f a ∂μ := lintegral_add_aux hf (hφm.sub hf)
_ ≤ ∫⁻ a, f a ∂μ + ∫⁻ a, g a ∂μ :=
add_le_add_left (lintegral_mono fun a => tsub_le_iff_left.2 <| hφ_le a) _
#align measure_theory.lintegral_add_left MeasureTheory.lintegral_add_left
theorem lintegral_add_left' {f : α → ℝ≥0∞} (hf : AEMeasurable f μ) (g : α → ℝ≥0∞) :
∫⁻ a, f a + g a ∂μ = ∫⁻ a, f a ∂μ + ∫⁻ a, g a ∂μ := by
rw [lintegral_congr_ae hf.ae_eq_mk, ← lintegral_add_left hf.measurable_mk,
lintegral_congr_ae (hf.ae_eq_mk.add (ae_eq_refl g))]
#align measure_theory.lintegral_add_left' MeasureTheory.lintegral_add_left'
theorem lintegral_add_right' (f : α → ℝ≥0∞) {g : α → ℝ≥0∞} (hg : AEMeasurable g μ) :
∫⁻ a, f a + g a ∂μ = ∫⁻ a, f a ∂μ + ∫⁻ a, g a ∂μ := by
simpa only [add_comm] using lintegral_add_left' hg f
#align measure_theory.lintegral_add_right' MeasureTheory.lintegral_add_right'
@[simp]
theorem lintegral_add_right (f : α → ℝ≥0∞) {g : α → ℝ≥0∞} (hg : Measurable g) :
∫⁻ a, f a + g a ∂μ = ∫⁻ a, f a ∂μ + ∫⁻ a, g a ∂μ :=
lintegral_add_right' f hg.aemeasurable
#align measure_theory.lintegral_add_right MeasureTheory.lintegral_add_right
@[simp]
theorem lintegral_smul_measure (c : ℝ≥0∞) (f : α → ℝ≥0∞) : ∫⁻ a, f a ∂c • μ = c * ∫⁻ a, f a ∂μ := by
simp only [lintegral, iSup_subtype', SimpleFunc.lintegral_smul, ENNReal.mul_iSup, smul_eq_mul]
#align measure_theory.lintegral_smul_measure MeasureTheory.lintegral_smul_measure
lemma set_lintegral_smul_measure (c : ℝ≥0∞) (f : α → ℝ≥0∞) (s : Set α) :
∫⁻ a in s, f a ∂(c • μ) = c * ∫⁻ a in s, f a ∂μ := by
rw [Measure.restrict_smul, lintegral_smul_measure]
@[simp]
theorem lintegral_sum_measure {m : MeasurableSpace α} {ι} (f : α → ℝ≥0∞) (μ : ι → Measure α) :
∫⁻ a, f a ∂Measure.sum μ = ∑' i, ∫⁻ a, f a ∂μ i := by
simp only [lintegral, iSup_subtype', SimpleFunc.lintegral_sum, ENNReal.tsum_eq_iSup_sum]
rw [iSup_comm]
congr; funext s
induction' s using Finset.induction_on with i s hi hs
· simp
simp only [Finset.sum_insert hi, ← hs]
refine (ENNReal.iSup_add_iSup ?_).symm
intro φ ψ
exact
⟨⟨φ ⊔ ψ, fun x => sup_le (φ.2 x) (ψ.2 x)⟩,
add_le_add (SimpleFunc.lintegral_mono le_sup_left le_rfl)
(Finset.sum_le_sum fun j _ => SimpleFunc.lintegral_mono le_sup_right le_rfl)⟩
#align measure_theory.lintegral_sum_measure MeasureTheory.lintegral_sum_measure
theorem hasSum_lintegral_measure {ι} {_ : MeasurableSpace α} (f : α → ℝ≥0∞) (μ : ι → Measure α) :
HasSum (fun i => ∫⁻ a, f a ∂μ i) (∫⁻ a, f a ∂Measure.sum μ) :=
(lintegral_sum_measure f μ).symm ▸ ENNReal.summable.hasSum
#align measure_theory.has_sum_lintegral_measure MeasureTheory.hasSum_lintegral_measure
@[simp]
theorem lintegral_add_measure {m : MeasurableSpace α} (f : α → ℝ≥0∞) (μ ν : Measure α) :
∫⁻ a, f a ∂(μ + ν) = ∫⁻ a, f a ∂μ + ∫⁻ a, f a ∂ν := by
simpa [tsum_fintype] using lintegral_sum_measure f fun b => cond b μ ν
#align measure_theory.lintegral_add_measure MeasureTheory.lintegral_add_measure
@[simp]
theorem lintegral_finset_sum_measure {ι} {m : MeasurableSpace α} (s : Finset ι) (f : α → ℝ≥0∞)
(μ : ι → Measure α) : ∫⁻ a, f a ∂(∑ i ∈ s, μ i) = ∑ i ∈ s, ∫⁻ a, f a ∂μ i := by
rw [← Measure.sum_coe_finset, lintegral_sum_measure, ← Finset.tsum_subtype']
simp only [Finset.coe_sort_coe]
#align measure_theory.lintegral_finset_sum_measure MeasureTheory.lintegral_finset_sum_measure
@[simp]
theorem lintegral_zero_measure {m : MeasurableSpace α} (f : α → ℝ≥0∞) :
∫⁻ a, f a ∂(0 : Measure α) = 0 := by
simp [lintegral]
#align measure_theory.lintegral_zero_measure MeasureTheory.lintegral_zero_measure
@[simp]
theorem lintegral_of_isEmpty {α} [MeasurableSpace α] [IsEmpty α] (μ : Measure α) (f : α → ℝ≥0∞) :
∫⁻ x, f x ∂μ = 0 := by
have : Subsingleton (Measure α) := inferInstance
convert lintegral_zero_measure f
theorem set_lintegral_empty (f : α → ℝ≥0∞) : ∫⁻ x in ∅, f x ∂μ = 0 := by
rw [Measure.restrict_empty, lintegral_zero_measure]
#align measure_theory.set_lintegral_empty MeasureTheory.set_lintegral_empty
theorem set_lintegral_univ (f : α → ℝ≥0∞) : ∫⁻ x in univ, f x ∂μ = ∫⁻ x, f x ∂μ := by
rw [Measure.restrict_univ]
#align measure_theory.set_lintegral_univ MeasureTheory.set_lintegral_univ
theorem set_lintegral_measure_zero (s : Set α) (f : α → ℝ≥0∞) (hs' : μ s = 0) :
∫⁻ x in s, f x ∂μ = 0 := by
convert lintegral_zero_measure _
exact Measure.restrict_eq_zero.2 hs'
#align measure_theory.set_lintegral_measure_zero MeasureTheory.set_lintegral_measure_zero
theorem lintegral_finset_sum' (s : Finset β) {f : β → α → ℝ≥0∞}
(hf : ∀ b ∈ s, AEMeasurable (f b) μ) :
∫⁻ a, ∑ b ∈ s, f b a ∂μ = ∑ b ∈ s, ∫⁻ a, f b a ∂μ := by
induction' s using Finset.induction_on with a s has ih
· simp
· simp only [Finset.sum_insert has]
rw [Finset.forall_mem_insert] at hf
rw [lintegral_add_left' hf.1, ih hf.2]
#align measure_theory.lintegral_finset_sum' MeasureTheory.lintegral_finset_sum'
theorem lintegral_finset_sum (s : Finset β) {f : β → α → ℝ≥0∞} (hf : ∀ b ∈ s, Measurable (f b)) :
∫⁻ a, ∑ b ∈ s, f b a ∂μ = ∑ b ∈ s, ∫⁻ a, f b a ∂μ :=
lintegral_finset_sum' s fun b hb => (hf b hb).aemeasurable
#align measure_theory.lintegral_finset_sum MeasureTheory.lintegral_finset_sum
@[simp]
theorem lintegral_const_mul (r : ℝ≥0∞) {f : α → ℝ≥0∞} (hf : Measurable f) :
∫⁻ a, r * f a ∂μ = r * ∫⁻ a, f a ∂μ :=
calc
∫⁻ a, r * f a ∂μ = ∫⁻ a, ⨆ n, (const α r * eapprox f n) a ∂μ := by
congr
funext a
rw [← iSup_eapprox_apply f hf, ENNReal.mul_iSup]
simp
_ = ⨆ n, r * (eapprox f n).lintegral μ := by
rw [lintegral_iSup]
· congr
funext n
rw [← SimpleFunc.const_mul_lintegral, ← SimpleFunc.lintegral_eq_lintegral]
· intro n
exact SimpleFunc.measurable _
· intro i j h a
exact mul_le_mul_left' (monotone_eapprox _ h _) _
_ = r * ∫⁻ a, f a ∂μ := by rw [← ENNReal.mul_iSup, lintegral_eq_iSup_eapprox_lintegral hf]
#align measure_theory.lintegral_const_mul MeasureTheory.lintegral_const_mul
theorem lintegral_const_mul'' (r : ℝ≥0∞) {f : α → ℝ≥0∞} (hf : AEMeasurable f μ) :
∫⁻ a, r * f a ∂μ = r * ∫⁻ a, f a ∂μ := by
have A : ∫⁻ a, f a ∂μ = ∫⁻ a, hf.mk f a ∂μ := lintegral_congr_ae hf.ae_eq_mk
have B : ∫⁻ a, r * f a ∂μ = ∫⁻ a, r * hf.mk f a ∂μ :=
lintegral_congr_ae (EventuallyEq.fun_comp hf.ae_eq_mk _)
rw [A, B, lintegral_const_mul _ hf.measurable_mk]
#align measure_theory.lintegral_const_mul'' MeasureTheory.lintegral_const_mul''
theorem lintegral_const_mul_le (r : ℝ≥0∞) (f : α → ℝ≥0∞) :
r * ∫⁻ a, f a ∂μ ≤ ∫⁻ a, r * f a ∂μ := by
rw [lintegral, ENNReal.mul_iSup]
refine iSup_le fun s => ?_
rw [ENNReal.mul_iSup, iSup_le_iff]
intro hs
rw [← SimpleFunc.const_mul_lintegral, lintegral]
refine le_iSup_of_le (const α r * s) (le_iSup_of_le (fun x => ?_) le_rfl)
exact mul_le_mul_left' (hs x) _
#align measure_theory.lintegral_const_mul_le MeasureTheory.lintegral_const_mul_le
theorem lintegral_const_mul' (r : ℝ≥0∞) (f : α → ℝ≥0∞) (hr : r ≠ ∞) :
∫⁻ a, r * f a ∂μ = r * ∫⁻ a, f a ∂μ := by
by_cases h : r = 0
· simp [h]
apply le_antisymm _ (lintegral_const_mul_le r f)
have rinv : r * r⁻¹ = 1 := ENNReal.mul_inv_cancel h hr
have rinv' : r⁻¹ * r = 1 := by
rw [mul_comm]
exact rinv
have := lintegral_const_mul_le (μ := μ) r⁻¹ fun x => r * f x
simp? [(mul_assoc _ _ _).symm, rinv'] at this says
simp only [(mul_assoc _ _ _).symm, rinv', one_mul] at this
simpa [(mul_assoc _ _ _).symm, rinv] using mul_le_mul_left' this r
#align measure_theory.lintegral_const_mul' MeasureTheory.lintegral_const_mul'
theorem lintegral_mul_const (r : ℝ≥0∞) {f : α → ℝ≥0∞} (hf : Measurable f) :
∫⁻ a, f a * r ∂μ = (∫⁻ a, f a ∂μ) * r := by simp_rw [mul_comm, lintegral_const_mul r hf]
#align measure_theory.lintegral_mul_const MeasureTheory.lintegral_mul_const
theorem lintegral_mul_const'' (r : ℝ≥0∞) {f : α → ℝ≥0∞} (hf : AEMeasurable f μ) :
∫⁻ a, f a * r ∂μ = (∫⁻ a, f a ∂μ) * r := by simp_rw [mul_comm, lintegral_const_mul'' r hf]
#align measure_theory.lintegral_mul_const'' MeasureTheory.lintegral_mul_const''
theorem lintegral_mul_const_le (r : ℝ≥0∞) (f : α → ℝ≥0∞) :
(∫⁻ a, f a ∂μ) * r ≤ ∫⁻ a, f a * r ∂μ := by
simp_rw [mul_comm, lintegral_const_mul_le r f]
#align measure_theory.lintegral_mul_const_le MeasureTheory.lintegral_mul_const_le
| Mathlib/MeasureTheory/Integral/Lebesgue.lean | 736 | 737 | theorem lintegral_mul_const' (r : ℝ≥0∞) (f : α → ℝ≥0∞) (hr : r ≠ ∞) :
∫⁻ a, f a * r ∂μ = (∫⁻ a, f a ∂μ) * r := by | simp_rw [mul_comm, lintegral_const_mul' r f hr]
|
import Mathlib.CategoryTheory.GlueData
import Mathlib.Topology.Category.TopCat.Limits.Pullbacks
import Mathlib.Topology.Category.TopCat.Opens
import Mathlib.Tactic.Generalize
import Mathlib.CategoryTheory.Elementwise
#align_import topology.gluing from "leanprover-community/mathlib"@"178a32653e369dce2da68dc6b2694e385d484ef1"
noncomputable section
open TopologicalSpace CategoryTheory
universe v u
open CategoryTheory.Limits
namespace TopCat
-- porting note (#5171): removed @[nolint has_nonempty_instance]
structure GlueData extends GlueData TopCat where
f_open : ∀ i j, OpenEmbedding (f i j)
f_mono := fun i j => (TopCat.mono_iff_injective _).mpr (f_open i j).toEmbedding.inj
set_option linter.uppercaseLean3 false in
#align Top.glue_data TopCat.GlueData
namespace GlueData
variable (D : GlueData.{u})
local notation "𝖣" => D.toGlueData
theorem π_surjective : Function.Surjective 𝖣.π :=
(TopCat.epi_iff_surjective 𝖣.π).mp inferInstance
set_option linter.uppercaseLean3 false in
#align Top.glue_data.π_surjective TopCat.GlueData.π_surjective
theorem isOpen_iff (U : Set 𝖣.glued) : IsOpen U ↔ ∀ i, IsOpen (𝖣.ι i ⁻¹' U) := by
delta CategoryTheory.GlueData.ι
simp_rw [← Multicoequalizer.ι_sigmaπ 𝖣.diagram]
rw [← (homeoOfIso (Multicoequalizer.isoCoequalizer 𝖣.diagram).symm).isOpen_preimage]
rw [coequalizer_isOpen_iff]
dsimp only [GlueData.diagram_l, GlueData.diagram_left, GlueData.diagram_r, GlueData.diagram_right,
parallelPair_obj_one]
rw [colimit_isOpen_iff.{_,u}] -- Porting note: changed `.{u}` to `.{_,u}`. fun fact: the proof
-- breaks down if this `rw` is merged with the `rw` above.
constructor
· intro h j; exact h ⟨j⟩
· intro h j; cases j; apply h
set_option linter.uppercaseLean3 false in
#align Top.glue_data.is_open_iff TopCat.GlueData.isOpen_iff
theorem ι_jointly_surjective (x : 𝖣.glued) : ∃ (i : _) (y : D.U i), 𝖣.ι i y = x :=
𝖣.ι_jointly_surjective (forget TopCat) x
set_option linter.uppercaseLean3 false in
#align Top.glue_data.ι_jointly_surjective TopCat.GlueData.ι_jointly_surjective
def Rel (a b : Σ i, ((D.U i : TopCat) : Type _)) : Prop :=
a = b ∨ ∃ x : D.V (a.1, b.1), D.f _ _ x = a.2 ∧ D.f _ _ (D.t _ _ x) = b.2
set_option linter.uppercaseLean3 false in
#align Top.glue_data.rel TopCat.GlueData.Rel
theorem rel_equiv : Equivalence D.Rel :=
⟨fun x => Or.inl (refl x), by
rintro a b (⟨⟨⟩⟩ | ⟨x, e₁, e₂⟩)
exacts [Or.inl rfl, Or.inr ⟨D.t _ _ x, e₂, by erw [← e₁, D.t_inv_apply]⟩], by
-- previous line now `erw` after #13170
rintro ⟨i, a⟩ ⟨j, b⟩ ⟨k, c⟩ (⟨⟨⟩⟩ | ⟨x, e₁, e₂⟩)
· exact id
rintro (⟨⟨⟩⟩ | ⟨y, e₃, e₄⟩)
· exact Or.inr ⟨x, e₁, e₂⟩
let z := (pullbackIsoProdSubtype (D.f j i) (D.f j k)).inv ⟨⟨_, _⟩, e₂.trans e₃.symm⟩
have eq₁ : (D.t j i) ((pullback.fst : _ ⟶ D.V (j, i)) z) = x := by
dsimp only [coe_of, z]
erw [pullbackIsoProdSubtype_inv_fst_apply, D.t_inv_apply]-- now `erw` after #13170
have eq₂ : (pullback.snd : _ ⟶ D.V _) z = y := pullbackIsoProdSubtype_inv_snd_apply _ _ _
clear_value z
right
use (pullback.fst : _ ⟶ D.V (i, k)) (D.t' _ _ _ z)
dsimp only at *
substs eq₁ eq₂ e₁ e₃ e₄
have h₁ : D.t' j i k ≫ pullback.fst ≫ D.f i k = pullback.fst ≫ D.t j i ≫ D.f i j := by
rw [← 𝖣.t_fac_assoc]; congr 1; exact pullback.condition
have h₂ : D.t' j i k ≫ pullback.fst ≫ D.t i k ≫ D.f k i = pullback.snd ≫ D.t j k ≫ D.f k j := by
rw [← 𝖣.t_fac_assoc]
apply @Epi.left_cancellation _ _ _ _ (D.t' k j i)
rw [𝖣.cocycle_assoc, 𝖣.t_fac_assoc, 𝖣.t_inv_assoc]
exact pullback.condition.symm
exact ⟨ContinuousMap.congr_fun h₁ z, ContinuousMap.congr_fun h₂ z⟩⟩
set_option linter.uppercaseLean3 false in
#align Top.glue_data.rel_equiv TopCat.GlueData.rel_equiv
open CategoryTheory.Limits.WalkingParallelPair
theorem eqvGen_of_π_eq
-- Porting note: was `{x y : ∐ D.U} (h : 𝖣.π x = 𝖣.π y)`
{x y : sigmaObj (β := D.toGlueData.J) (C := TopCat) D.toGlueData.U}
(h : 𝖣.π x = 𝖣.π y) :
EqvGen
-- Porting note: was (Types.CoequalizerRel 𝖣.diagram.fstSigmaMap 𝖣.diagram.sndSigmaMap)
(Types.CoequalizerRel
(X := sigmaObj (β := D.toGlueData.diagram.L) (C := TopCat) (D.toGlueData.diagram).left)
(Y := sigmaObj (β := D.toGlueData.diagram.R) (C := TopCat) (D.toGlueData.diagram).right)
𝖣.diagram.fstSigmaMap 𝖣.diagram.sndSigmaMap)
x y := by
delta GlueData.π Multicoequalizer.sigmaπ at h
-- Porting note: inlined `inferInstance` instead of leaving as a side goal.
replace h := (TopCat.mono_iff_injective (Multicoequalizer.isoCoequalizer 𝖣.diagram).inv).mp
inferInstance h
let diagram := parallelPair 𝖣.diagram.fstSigmaMap 𝖣.diagram.sndSigmaMap ⋙ forget _
have : colimit.ι diagram one x = colimit.ι diagram one y := by
dsimp only [coequalizer.π, ContinuousMap.toFun_eq_coe] at h
-- This used to be `rw`, but we need `erw` after leanprover/lean4#2644
erw [← ι_preservesColimitsIso_hom, forget_map_eq_coe, types_comp_apply, h]
simp
rfl
have :
(colimit.ι diagram _ ≫ colim.map _ ≫ (colimit.isoColimitCocone _).hom) _ =
(colimit.ι diagram _ ≫ colim.map _ ≫ (colimit.isoColimitCocone _).hom) _ :=
(congr_arg
(colim.map (diagramIsoParallelPair diagram).hom ≫
(colimit.isoColimitCocone (Types.coequalizerColimit _ _)).hom)
this :
_)
-- Porting note: was
-- simp only [eqToHom_refl, types_comp_apply, colimit.ι_map_assoc,
-- diagramIsoParallelPair_hom_app, colimit.isoColimitCocone_ι_hom, types_id_apply] at this
-- See https://github.com/leanprover-community/mathlib4/issues/5026
rw [colimit.ι_map_assoc, diagramIsoParallelPair_hom_app, eqToHom_refl,
colimit.isoColimitCocone_ι_hom, types_comp_apply, types_id_apply, types_comp_apply,
types_id_apply] at this
exact Quot.eq.1 this
set_option linter.uppercaseLean3 false in
#align Top.glue_data.eqv_gen_of_π_eq TopCat.GlueData.eqvGen_of_π_eq
theorem ι_eq_iff_rel (i j : D.J) (x : D.U i) (y : D.U j) :
𝖣.ι i x = 𝖣.ι j y ↔ D.Rel ⟨i, x⟩ ⟨j, y⟩ := by
constructor
· delta GlueData.ι
simp_rw [← Multicoequalizer.ι_sigmaπ]
intro h
rw [←
show _ = Sigma.mk i x from ConcreteCategory.congr_hom (sigmaIsoSigma.{_, u} D.U).inv_hom_id _]
rw [←
show _ = Sigma.mk j y from ConcreteCategory.congr_hom (sigmaIsoSigma.{_, u} D.U).inv_hom_id _]
change InvImage D.Rel (sigmaIsoSigma.{_, u} D.U).hom _ _
rw [← (InvImage.equivalence _ _ D.rel_equiv).eqvGen_iff]
refine EqvGen.mono ?_ (D.eqvGen_of_π_eq h : _)
rintro _ _ ⟨x⟩
obtain ⟨⟨⟨i, j⟩, y⟩, rfl⟩ :=
(ConcreteCategory.bijective_of_isIso (sigmaIsoSigma.{u, u} _).inv).2 x
unfold InvImage MultispanIndex.fstSigmaMap MultispanIndex.sndSigmaMap
simp only [forget_map_eq_coe]
erw [TopCat.comp_app, sigmaIsoSigma_inv_apply, ← comp_apply, ← comp_apply,
colimit.ι_desc_assoc, ← comp_apply, ← comp_apply, colimit.ι_desc_assoc]
-- previous line now `erw` after #13170
erw [sigmaIsoSigma_hom_ι_apply, sigmaIsoSigma_hom_ι_apply]
exact Or.inr ⟨y, ⟨rfl, rfl⟩⟩
· rintro (⟨⟨⟩⟩ | ⟨z, e₁, e₂⟩)
· rfl
dsimp only at *
-- Porting note: there were `subst e₁` and `subst e₂`, instead of the `rw`
rw [← e₁, ← e₂] at *
erw [D.glue_condition_apply] -- now `erw` after #13170
rfl -- now `rfl` after #13170
set_option linter.uppercaseLean3 false in
#align Top.glue_data.ι_eq_iff_rel TopCat.GlueData.ι_eq_iff_rel
| Mathlib/Topology/Gluing.lean | 238 | 245 | theorem ι_injective (i : D.J) : Function.Injective (𝖣.ι i) := by |
intro x y h
rcases (D.ι_eq_iff_rel _ _ _ _).mp h with (⟨⟨⟩⟩ | ⟨_, e₁, e₂⟩)
· rfl
· dsimp only at *
-- Porting note: there were `cases e₁` and `cases e₂`, instead of the `rw`
rw [← e₁, ← e₂]
simp
|
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]
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),
eval₂_at_natCast,Nat.cast_id]
#align pochhammer_eval_cast ascPochhammer_eval_cast
theorem ascPochhammer_eval_zero {n : ℕ} : (ascPochhammer S n).eval 0 = if n = 0 then 1 else 0 := by
cases n
· simp
· simp [X_mul, Nat.succ_ne_zero, ascPochhammer_succ_left]
#align pochhammer_eval_zero ascPochhammer_eval_zero
theorem ascPochhammer_zero_eval_zero : (ascPochhammer S 0).eval 0 = 1 := by simp
#align pochhammer_zero_eval_zero ascPochhammer_zero_eval_zero
@[simp]
theorem ascPochhammer_ne_zero_eval_zero {n : ℕ} (h : n ≠ 0) : (ascPochhammer S n).eval 0 = 0 := by
simp [ascPochhammer_eval_zero, h]
#align pochhammer_ne_zero_eval_zero ascPochhammer_ne_zero_eval_zero
| Mathlib/RingTheory/Polynomial/Pochhammer.lean | 124 | 134 | theorem ascPochhammer_succ_right (n : ℕ) :
ascPochhammer S (n + 1) = ascPochhammer S n * (X + (n : S[X])) := by |
suffices h : ascPochhammer ℕ (n + 1) = ascPochhammer ℕ n * (X + (n : ℕ[X])) by
apply_fun Polynomial.map (algebraMap ℕ S) at h
simpa only [ascPochhammer_map, Polynomial.map_mul, Polynomial.map_add, map_X,
Polynomial.map_natCast] using h
induction' n with n ih
· simp
· conv_lhs =>
rw [ascPochhammer_succ_left, ih, mul_comp, ← mul_assoc, ← ascPochhammer_succ_left, add_comp,
X_comp, natCast_comp, add_assoc, add_comm (1 : ℕ[X]), ← Nat.cast_succ]
|
import Mathlib.Probability.Variance
import Mathlib.MeasureTheory.Function.UniformIntegrable
#align_import probability.ident_distrib from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982"
open MeasureTheory Filter Finset
noncomputable section
open scoped Topology MeasureTheory ENNReal NNReal
variable {α β γ δ : Type*} [MeasurableSpace α] [MeasurableSpace β] [MeasurableSpace γ]
[MeasurableSpace δ]
namespace ProbabilityTheory
structure IdentDistrib (f : α → γ) (g : β → γ)
(μ : Measure α := by volume_tac)
(ν : Measure β := by volume_tac) : Prop where
aemeasurable_fst : AEMeasurable f μ
aemeasurable_snd : AEMeasurable g ν
map_eq : Measure.map f μ = Measure.map g ν
#align probability_theory.ident_distrib ProbabilityTheory.IdentDistrib
namespace IdentDistrib
open TopologicalSpace
variable {μ : Measure α} {ν : Measure β} {f : α → γ} {g : β → γ}
protected theorem refl (hf : AEMeasurable f μ) : IdentDistrib f f μ μ :=
{ aemeasurable_fst := hf
aemeasurable_snd := hf
map_eq := rfl }
#align probability_theory.ident_distrib.refl ProbabilityTheory.IdentDistrib.refl
protected theorem symm (h : IdentDistrib f g μ ν) : IdentDistrib g f ν μ :=
{ aemeasurable_fst := h.aemeasurable_snd
aemeasurable_snd := h.aemeasurable_fst
map_eq := h.map_eq.symm }
#align probability_theory.ident_distrib.symm ProbabilityTheory.IdentDistrib.symm
protected theorem trans {ρ : Measure δ} {h : δ → γ} (h₁ : IdentDistrib f g μ ν)
(h₂ : IdentDistrib g h ν ρ) : IdentDistrib f h μ ρ :=
{ aemeasurable_fst := h₁.aemeasurable_fst
aemeasurable_snd := h₂.aemeasurable_snd
map_eq := h₁.map_eq.trans h₂.map_eq }
#align probability_theory.ident_distrib.trans ProbabilityTheory.IdentDistrib.trans
protected theorem comp_of_aemeasurable {u : γ → δ} (h : IdentDistrib f g μ ν)
(hu : AEMeasurable u (Measure.map f μ)) : IdentDistrib (u ∘ f) (u ∘ g) μ ν :=
{ aemeasurable_fst := hu.comp_aemeasurable h.aemeasurable_fst
aemeasurable_snd := by rw [h.map_eq] at hu; exact hu.comp_aemeasurable h.aemeasurable_snd
map_eq := by
rw [← AEMeasurable.map_map_of_aemeasurable hu h.aemeasurable_fst, ←
AEMeasurable.map_map_of_aemeasurable _ h.aemeasurable_snd, h.map_eq]
rwa [← h.map_eq] }
#align probability_theory.ident_distrib.comp_of_ae_measurable ProbabilityTheory.IdentDistrib.comp_of_aemeasurable
protected theorem comp {u : γ → δ} (h : IdentDistrib f g μ ν) (hu : Measurable u) :
IdentDistrib (u ∘ f) (u ∘ g) μ ν :=
h.comp_of_aemeasurable hu.aemeasurable
#align probability_theory.ident_distrib.comp ProbabilityTheory.IdentDistrib.comp
protected theorem of_ae_eq {g : α → γ} (hf : AEMeasurable f μ) (heq : f =ᵐ[μ] g) :
IdentDistrib f g μ μ :=
{ aemeasurable_fst := hf
aemeasurable_snd := hf.congr heq
map_eq := Measure.map_congr heq }
#align probability_theory.ident_distrib.of_ae_eq ProbabilityTheory.IdentDistrib.of_ae_eq
lemma _root_.MeasureTheory.AEMeasurable.identDistrib_mk
(hf : AEMeasurable f μ) : IdentDistrib f (hf.mk f) μ μ :=
IdentDistrib.of_ae_eq hf hf.ae_eq_mk
lemma _root_.MeasureTheory.AEStronglyMeasurable.identDistrib_mk
[TopologicalSpace γ] [PseudoMetrizableSpace γ] [BorelSpace γ]
(hf : AEStronglyMeasurable f μ) : IdentDistrib f (hf.mk f) μ μ :=
IdentDistrib.of_ae_eq hf.aemeasurable hf.ae_eq_mk
theorem measure_mem_eq (h : IdentDistrib f g μ ν) {s : Set γ} (hs : MeasurableSet s) :
μ (f ⁻¹' s) = ν (g ⁻¹' s) := by
rw [← Measure.map_apply_of_aemeasurable h.aemeasurable_fst hs, ←
Measure.map_apply_of_aemeasurable h.aemeasurable_snd hs, h.map_eq]
#align probability_theory.ident_distrib.measure_mem_eq ProbabilityTheory.IdentDistrib.measure_mem_eq
alias measure_preimage_eq := measure_mem_eq
#align probability_theory.ident_distrib.measure_preimage_eq ProbabilityTheory.IdentDistrib.measure_preimage_eq
theorem ae_snd (h : IdentDistrib f g μ ν) {p : γ → Prop} (pmeas : MeasurableSet {x | p x})
(hp : ∀ᵐ x ∂μ, p (f x)) : ∀ᵐ x ∂ν, p (g x) := by
apply (ae_map_iff h.aemeasurable_snd pmeas).1
rw [← h.map_eq]
exact (ae_map_iff h.aemeasurable_fst pmeas).2 hp
#align probability_theory.ident_distrib.ae_snd ProbabilityTheory.IdentDistrib.ae_snd
theorem ae_mem_snd (h : IdentDistrib f g μ ν) {t : Set γ} (tmeas : MeasurableSet t)
(ht : ∀ᵐ x ∂μ, f x ∈ t) : ∀ᵐ x ∂ν, g x ∈ t :=
h.ae_snd tmeas ht
#align probability_theory.ident_distrib.ae_mem_snd ProbabilityTheory.IdentDistrib.ae_mem_snd
theorem aestronglyMeasurable_fst [TopologicalSpace γ] [MetrizableSpace γ] [OpensMeasurableSpace γ]
[SecondCountableTopology γ] (h : IdentDistrib f g μ ν) : AEStronglyMeasurable f μ :=
h.aemeasurable_fst.aestronglyMeasurable
#align probability_theory.ident_distrib.ae_strongly_measurable_fst ProbabilityTheory.IdentDistrib.aestronglyMeasurable_fst
theorem aestronglyMeasurable_snd [TopologicalSpace γ] [MetrizableSpace γ] [BorelSpace γ]
(h : IdentDistrib f g μ ν) (hf : AEStronglyMeasurable f μ) : AEStronglyMeasurable g ν := by
refine aestronglyMeasurable_iff_aemeasurable_separable.2 ⟨h.aemeasurable_snd, ?_⟩
rcases (aestronglyMeasurable_iff_aemeasurable_separable.1 hf).2 with ⟨t, t_sep, ht⟩
refine ⟨closure t, t_sep.closure, ?_⟩
apply h.ae_mem_snd isClosed_closure.measurableSet
filter_upwards [ht] with x hx using subset_closure hx
#align probability_theory.ident_distrib.ae_strongly_measurable_snd ProbabilityTheory.IdentDistrib.aestronglyMeasurable_snd
theorem aestronglyMeasurable_iff [TopologicalSpace γ] [MetrizableSpace γ] [BorelSpace γ]
(h : IdentDistrib f g μ ν) : AEStronglyMeasurable f μ ↔ AEStronglyMeasurable g ν :=
⟨fun hf => h.aestronglyMeasurable_snd hf, fun hg => h.symm.aestronglyMeasurable_snd hg⟩
#align probability_theory.ident_distrib.ae_strongly_measurable_iff ProbabilityTheory.IdentDistrib.aestronglyMeasurable_iff
theorem essSup_eq [ConditionallyCompleteLinearOrder γ] [TopologicalSpace γ] [OpensMeasurableSpace γ]
[OrderClosedTopology γ] (h : IdentDistrib f g μ ν) : essSup f μ = essSup g ν := by
have I : ∀ a, μ {x : α | a < f x} = ν {x : β | a < g x} := fun a =>
h.measure_mem_eq measurableSet_Ioi
simp_rw [essSup_eq_sInf, I]
#align probability_theory.ident_distrib.ess_sup_eq ProbabilityTheory.IdentDistrib.essSup_eq
theorem lintegral_eq {f : α → ℝ≥0∞} {g : β → ℝ≥0∞} (h : IdentDistrib f g μ ν) :
∫⁻ x, f x ∂μ = ∫⁻ x, g x ∂ν := by
change ∫⁻ x, id (f x) ∂μ = ∫⁻ x, id (g x) ∂ν
rw [← lintegral_map' aemeasurable_id h.aemeasurable_fst, ←
lintegral_map' aemeasurable_id h.aemeasurable_snd, h.map_eq]
#align probability_theory.ident_distrib.lintegral_eq ProbabilityTheory.IdentDistrib.lintegral_eq
theorem integral_eq [NormedAddCommGroup γ] [NormedSpace ℝ γ] [BorelSpace γ]
(h : IdentDistrib f g μ ν) : ∫ x, f x ∂μ = ∫ x, g x ∂ν := by
by_cases hf : AEStronglyMeasurable f μ
· have A : AEStronglyMeasurable id (Measure.map f μ) := by
rw [aestronglyMeasurable_iff_aemeasurable_separable]
rcases (aestronglyMeasurable_iff_aemeasurable_separable.1 hf).2 with ⟨t, t_sep, ht⟩
refine ⟨aemeasurable_id, ⟨closure t, t_sep.closure, ?_⟩⟩
rw [ae_map_iff h.aemeasurable_fst]
· filter_upwards [ht] with x hx using subset_closure hx
· exact isClosed_closure.measurableSet
change ∫ x, id (f x) ∂μ = ∫ x, id (g x) ∂ν
rw [← integral_map h.aemeasurable_fst A]
rw [h.map_eq] at A
rw [← integral_map h.aemeasurable_snd A, h.map_eq]
· rw [integral_non_aestronglyMeasurable hf]
rw [h.aestronglyMeasurable_iff] at hf
rw [integral_non_aestronglyMeasurable hf]
#align probability_theory.ident_distrib.integral_eq ProbabilityTheory.IdentDistrib.integral_eq
theorem snorm_eq [NormedAddCommGroup γ] [OpensMeasurableSpace γ] (h : IdentDistrib f g μ ν)
(p : ℝ≥0∞) : snorm f p μ = snorm g p ν := by
by_cases h0 : p = 0
· simp [h0]
by_cases h_top : p = ∞
· simp only [h_top, snorm, snormEssSup, ENNReal.top_ne_zero, eq_self_iff_true, if_true, if_false]
apply essSup_eq
exact h.comp (measurable_coe_nnreal_ennreal.comp measurable_nnnorm)
simp only [snorm_eq_snorm' h0 h_top, snorm', one_div]
congr 1
apply lintegral_eq
exact h.comp (Measurable.pow_const (measurable_coe_nnreal_ennreal.comp measurable_nnnorm)
p.toReal)
#align probability_theory.ident_distrib.snorm_eq ProbabilityTheory.IdentDistrib.snorm_eq
| Mathlib/Probability/IdentDistrib.lean | 224 | 228 | theorem memℒp_snd [NormedAddCommGroup γ] [BorelSpace γ] {p : ℝ≥0∞} (h : IdentDistrib f g μ ν)
(hf : Memℒp f p μ) : Memℒp g p ν := by |
refine ⟨h.aestronglyMeasurable_snd hf.aestronglyMeasurable, ?_⟩
rw [← h.snorm_eq]
exact hf.2
|
import Mathlib.MeasureTheory.Integral.Bochner
import Mathlib.MeasureTheory.Group.Measure
#align_import measure_theory.group.integration from "leanprover-community/mathlib"@"ec247d43814751ffceb33b758e8820df2372bf6f"
namespace MeasureTheory
open Measure TopologicalSpace
open scoped ENNReal
variable {𝕜 M α G E F : Type*} [MeasurableSpace G]
variable [NormedAddCommGroup E] [NormedSpace ℝ E] [CompleteSpace E] [NormedAddCommGroup F]
variable {μ : Measure G} {f : G → E} {g : G}
section MeasurableMul
variable [Group G] [MeasurableMul G]
@[to_additive
"Translating a function by left-addition does not change its integral with respect to a
left-invariant measure."] -- Porting note: was `@[simp]`
theorem integral_mul_left_eq_self [IsMulLeftInvariant μ] (f : G → E) (g : G) :
(∫ x, f (g * x) ∂μ) = ∫ x, f x ∂μ := by
have h_mul : MeasurableEmbedding fun x => g * x := (MeasurableEquiv.mulLeft g).measurableEmbedding
rw [← h_mul.integral_map, map_mul_left_eq_self]
#align measure_theory.integral_mul_left_eq_self MeasureTheory.integral_mul_left_eq_self
#align measure_theory.integral_add_left_eq_self MeasureTheory.integral_add_left_eq_self
@[to_additive
"Translating a function by right-addition does not change its integral with respect to a
right-invariant measure."] -- Porting note: was `@[simp]`
theorem integral_mul_right_eq_self [IsMulRightInvariant μ] (f : G → E) (g : G) :
(∫ x, f (x * g) ∂μ) = ∫ x, f x ∂μ := by
have h_mul : MeasurableEmbedding fun x => x * g :=
(MeasurableEquiv.mulRight g).measurableEmbedding
rw [← h_mul.integral_map, map_mul_right_eq_self]
#align measure_theory.integral_mul_right_eq_self MeasureTheory.integral_mul_right_eq_self
#align measure_theory.integral_add_right_eq_self MeasureTheory.integral_add_right_eq_self
@[to_additive] -- Porting note: was `@[simp]`
| Mathlib/MeasureTheory/Group/Integral.lean | 79 | 83 | theorem integral_div_right_eq_self [IsMulRightInvariant μ] (f : G → E) (g : G) :
(∫ x, f (x / g) ∂μ) = ∫ x, f x ∂μ := by |
simp_rw [div_eq_mul_inv]
-- Porting note: was `simp_rw`
rw [integral_mul_right_eq_self f g⁻¹]
|
import Batteries.Data.List.Count
import Batteries.Data.Fin.Lemmas
open Nat Function
namespace List
theorem rel_of_pairwise_cons (p : (a :: l).Pairwise R) : ∀ {a'}, a' ∈ l → R a a' :=
(pairwise_cons.1 p).1 _
theorem Pairwise.of_cons (p : (a :: l).Pairwise R) : Pairwise R l :=
(pairwise_cons.1 p).2
theorem Pairwise.tail : ∀ {l : List α} (_p : Pairwise R l), Pairwise R l.tail
| [], h => h
| _ :: _, h => h.of_cons
theorem Pairwise.drop : ∀ {l : List α} {n : Nat}, List.Pairwise R l → List.Pairwise R (l.drop n)
| _, 0, h => h
| [], _ + 1, _ => List.Pairwise.nil
| _ :: _, n + 1, h => Pairwise.drop (n := n) (pairwise_cons.mp h).right
theorem Pairwise.imp_of_mem {S : α → α → Prop}
(H : ∀ {a b}, a ∈ l → b ∈ l → R a b → S a b) (p : Pairwise R l) : Pairwise S l := by
induction p with
| nil => constructor
| @cons a l r _ ih =>
constructor
· exact fun x h => H (mem_cons_self ..) (mem_cons_of_mem _ h) <| r x h
· exact ih fun m m' => H (mem_cons_of_mem _ m) (mem_cons_of_mem _ m')
theorem Pairwise.and (hR : Pairwise R l) (hS : Pairwise S l) :
l.Pairwise fun a b => R a b ∧ S a b := by
induction hR with
| nil => simp only [Pairwise.nil]
| cons R1 _ IH =>
simp only [Pairwise.nil, pairwise_cons] at hS ⊢
exact ⟨fun b bl => ⟨R1 b bl, hS.1 b bl⟩, IH hS.2⟩
theorem pairwise_and_iff : l.Pairwise (fun a b => R a b ∧ S a b) ↔ Pairwise R l ∧ Pairwise S l :=
⟨fun h => ⟨h.imp fun h => h.1, h.imp fun h => h.2⟩, fun ⟨hR, hS⟩ => hR.and hS⟩
theorem Pairwise.imp₂ (H : ∀ a b, R a b → S a b → T a b)
(hR : Pairwise R l) (hS : l.Pairwise S) : l.Pairwise T :=
(hR.and hS).imp fun ⟨h₁, h₂⟩ => H _ _ h₁ h₂
theorem Pairwise.iff_of_mem {S : α → α → Prop} {l : List α}
(H : ∀ {a b}, a ∈ l → b ∈ l → (R a b ↔ S a b)) : Pairwise R l ↔ Pairwise S l :=
⟨Pairwise.imp_of_mem fun m m' => (H m m').1, Pairwise.imp_of_mem fun m m' => (H m m').2⟩
theorem Pairwise.iff {S : α → α → Prop} (H : ∀ a b, R a b ↔ S a b) {l : List α} :
Pairwise R l ↔ Pairwise S l :=
Pairwise.iff_of_mem fun _ _ => H ..
theorem pairwise_of_forall {l : List α} (H : ∀ x y, R x y) : Pairwise R l := by
induction l <;> simp [*]
theorem Pairwise.and_mem {l : List α} :
Pairwise R l ↔ Pairwise (fun x y => x ∈ l ∧ y ∈ l ∧ R x y) l :=
Pairwise.iff_of_mem <| by simp (config := { contextual := true })
theorem Pairwise.imp_mem {l : List α} :
Pairwise R l ↔ Pairwise (fun x y => x ∈ l → y ∈ l → R x y) l :=
Pairwise.iff_of_mem <| by simp (config := { contextual := true })
theorem Pairwise.forall_of_forall_of_flip (h₁ : ∀ x ∈ l, R x x) (h₂ : Pairwise R l)
(h₃ : l.Pairwise (flip R)) : ∀ ⦃x⦄, x ∈ l → ∀ ⦃y⦄, y ∈ l → R x y := by
induction l with
| nil => exact forall_mem_nil _
| cons a l ih =>
rw [pairwise_cons] at h₂ h₃
simp only [mem_cons]
rintro x (rfl | hx) y (rfl | hy)
· exact h₁ _ (l.mem_cons_self _)
· exact h₂.1 _ hy
· exact h₃.1 _ hx
· exact ih (fun x hx => h₁ _ <| mem_cons_of_mem _ hx) h₂.2 h₃.2 hx hy
theorem pairwise_singleton (R) (a : α) : Pairwise R [a] := by simp
theorem pairwise_pair {a b : α} : Pairwise R [a, b] ↔ R a b := by simp
theorem pairwise_append_comm {R : α → α → Prop} (s : ∀ {x y}, R x y → R y x) {l₁ l₂ : List α} :
Pairwise R (l₁ ++ l₂) ↔ Pairwise R (l₂ ++ l₁) := by
have (l₁ l₂ : List α) (H : ∀ x : α, x ∈ l₁ → ∀ y : α, y ∈ l₂ → R x y)
(x : α) (xm : x ∈ l₂) (y : α) (ym : y ∈ l₁) : R x y := s (H y ym x xm)
simp only [pairwise_append, and_left_comm]; rw [Iff.intro (this l₁ l₂) (this l₂ l₁)]
| .lake/packages/batteries/Batteries/Data/List/Pairwise.lean | 114 | 118 | theorem pairwise_middle {R : α → α → Prop} (s : ∀ {x y}, R x y → R y x) {a : α} {l₁ l₂ : List α} :
Pairwise R (l₁ ++ a :: l₂) ↔ Pairwise R (a :: (l₁ ++ l₂)) := by |
show Pairwise R (l₁ ++ ([a] ++ l₂)) ↔ Pairwise R ([a] ++ l₁ ++ l₂)
rw [← append_assoc, pairwise_append, @pairwise_append _ _ ([a] ++ l₁), pairwise_append_comm s]
simp only [mem_append, or_comm]
|
import Mathlib.SetTheory.Game.State
#align_import set_theory.game.domineering from "leanprover-community/mathlib"@"b134b2f5cf6dd25d4bbfd3c498b6e36c11a17225"
namespace SetTheory
namespace PGame
namespace Domineering
open Function
@[simps!]
def shiftUp : ℤ × ℤ ≃ ℤ × ℤ :=
(Equiv.refl ℤ).prodCongr (Equiv.addRight (1 : ℤ))
#align pgame.domineering.shift_up SetTheory.PGame.Domineering.shiftUp
@[simps!]
def shiftRight : ℤ × ℤ ≃ ℤ × ℤ :=
(Equiv.addRight (1 : ℤ)).prodCongr (Equiv.refl ℤ)
#align pgame.domineering.shift_right SetTheory.PGame.Domineering.shiftRight
-- Porting note: reducibility cannot be `local`. For now there are no dependents of this file so
-- being globally reducible is fine.
abbrev Board :=
Finset (ℤ × ℤ)
#align pgame.domineering.board SetTheory.PGame.Domineering.Board
def left (b : Board) : Finset (ℤ × ℤ) :=
b ∩ b.map shiftUp
#align pgame.domineering.left SetTheory.PGame.Domineering.left
def right (b : Board) : Finset (ℤ × ℤ) :=
b ∩ b.map shiftRight
#align pgame.domineering.right SetTheory.PGame.Domineering.right
theorem mem_left {b : Board} (x : ℤ × ℤ) : x ∈ left b ↔ x ∈ b ∧ (x.1, x.2 - 1) ∈ b :=
Finset.mem_inter.trans (and_congr Iff.rfl Finset.mem_map_equiv)
#align pgame.domineering.mem_left SetTheory.PGame.Domineering.mem_left
theorem mem_right {b : Board} (x : ℤ × ℤ) : x ∈ right b ↔ x ∈ b ∧ (x.1 - 1, x.2) ∈ b :=
Finset.mem_inter.trans (and_congr Iff.rfl Finset.mem_map_equiv)
#align pgame.domineering.mem_right SetTheory.PGame.Domineering.mem_right
def moveLeft (b : Board) (m : ℤ × ℤ) : Board :=
(b.erase m).erase (m.1, m.2 - 1)
#align pgame.domineering.move_left SetTheory.PGame.Domineering.moveLeft
def moveRight (b : Board) (m : ℤ × ℤ) : Board :=
(b.erase m).erase (m.1 - 1, m.2)
#align pgame.domineering.move_right SetTheory.PGame.Domineering.moveRight
theorem fst_pred_mem_erase_of_mem_right {b : Board} {m : ℤ × ℤ} (h : m ∈ right b) :
(m.1 - 1, m.2) ∈ b.erase m := by
rw [mem_right] at h
apply Finset.mem_erase_of_ne_of_mem _ h.2
exact ne_of_apply_ne Prod.fst (pred_ne_self m.1)
#align pgame.domineering.fst_pred_mem_erase_of_mem_right SetTheory.PGame.Domineering.fst_pred_mem_erase_of_mem_right
theorem snd_pred_mem_erase_of_mem_left {b : Board} {m : ℤ × ℤ} (h : m ∈ left b) :
(m.1, m.2 - 1) ∈ b.erase m := by
rw [mem_left] at h
apply Finset.mem_erase_of_ne_of_mem _ h.2
exact ne_of_apply_ne Prod.snd (pred_ne_self m.2)
#align pgame.domineering.snd_pred_mem_erase_of_mem_left SetTheory.PGame.Domineering.snd_pred_mem_erase_of_mem_left
theorem card_of_mem_left {b : Board} {m : ℤ × ℤ} (h : m ∈ left b) : 2 ≤ Finset.card b := by
have w₁ : m ∈ b := (Finset.mem_inter.1 h).1
have w₂ : (m.1, m.2 - 1) ∈ b.erase m := snd_pred_mem_erase_of_mem_left h
have i₁ := Finset.card_erase_lt_of_mem w₁
have i₂ := Nat.lt_of_le_of_lt (Nat.zero_le _) (Finset.card_erase_lt_of_mem w₂)
exact Nat.lt_of_le_of_lt i₂ i₁
#align pgame.domineering.card_of_mem_left SetTheory.PGame.Domineering.card_of_mem_left
theorem card_of_mem_right {b : Board} {m : ℤ × ℤ} (h : m ∈ right b) : 2 ≤ Finset.card b := by
have w₁ : m ∈ b := (Finset.mem_inter.1 h).1
have w₂ := fst_pred_mem_erase_of_mem_right h
have i₁ := Finset.card_erase_lt_of_mem w₁
have i₂ := Nat.lt_of_le_of_lt (Nat.zero_le _) (Finset.card_erase_lt_of_mem w₂)
exact Nat.lt_of_le_of_lt i₂ i₁
#align pgame.domineering.card_of_mem_right SetTheory.PGame.Domineering.card_of_mem_right
| Mathlib/SetTheory/Game/Domineering.lean | 109 | 114 | theorem moveLeft_card {b : Board} {m : ℤ × ℤ} (h : m ∈ left b) :
Finset.card (moveLeft b m) + 2 = Finset.card b := by |
dsimp [moveLeft]
rw [Finset.card_erase_of_mem (snd_pred_mem_erase_of_mem_left h)]
rw [Finset.card_erase_of_mem (Finset.mem_of_mem_inter_left h)]
exact tsub_add_cancel_of_le (card_of_mem_left h)
|
import Mathlib.CategoryTheory.Comma.Arrow
import Mathlib.CategoryTheory.Pi.Basic
import Mathlib.Order.CompleteBooleanAlgebra
#align_import category_theory.morphism_property from "leanprover-community/mathlib"@"7f963633766aaa3ebc8253100a5229dd463040c7"
universe w v v' u u'
open CategoryTheory Opposite
noncomputable section
namespace CategoryTheory
variable (C : Type u) [Category.{v} C] {D : Type*} [Category D]
def MorphismProperty :=
∀ ⦃X Y : C⦄ (_ : X ⟶ Y), Prop
#align category_theory.morphism_property CategoryTheory.MorphismProperty
instance : CompleteBooleanAlgebra (MorphismProperty C) where
le P₁ P₂ := ∀ ⦃X Y : C⦄ (f : X ⟶ Y), P₁ f → P₂ f
__ := inferInstanceAs (CompleteBooleanAlgebra (∀ ⦃X Y : C⦄ (_ : X ⟶ Y), Prop))
lemma MorphismProperty.le_def {P Q : MorphismProperty C} :
P ≤ Q ↔ ∀ {X Y : C} (f : X ⟶ Y), P f → Q f := Iff.rfl
instance : Inhabited (MorphismProperty C) :=
⟨⊤⟩
lemma MorphismProperty.top_eq : (⊤ : MorphismProperty C) = fun _ _ _ => True := rfl
variable {C}
namespace MorphismProperty
@[ext]
lemma ext (W W' : MorphismProperty C) (h : ∀ ⦃X Y : C⦄ (f : X ⟶ Y), W f ↔ W' f) :
W = W' := by
funext X Y f
rw [h]
@[simp]
lemma top_apply {X Y : C} (f : X ⟶ Y) : (⊤ : MorphismProperty C) f := by
simp only [top_eq]
@[simp]
def op (P : MorphismProperty C) : MorphismProperty Cᵒᵖ := fun _ _ f => P f.unop
#align category_theory.morphism_property.op CategoryTheory.MorphismProperty.op
@[simp]
def unop (P : MorphismProperty Cᵒᵖ) : MorphismProperty C := fun _ _ f => P f.op
#align category_theory.morphism_property.unop CategoryTheory.MorphismProperty.unop
theorem unop_op (P : MorphismProperty C) : P.op.unop = P :=
rfl
#align category_theory.morphism_property.unop_op CategoryTheory.MorphismProperty.unop_op
theorem op_unop (P : MorphismProperty Cᵒᵖ) : P.unop.op = P :=
rfl
#align category_theory.morphism_property.op_unop CategoryTheory.MorphismProperty.op_unop
def inverseImage (P : MorphismProperty D) (F : C ⥤ D) : MorphismProperty C := fun _ _ f =>
P (F.map f)
#align category_theory.morphism_property.inverse_image CategoryTheory.MorphismProperty.inverseImage
@[simp]
lemma inverseImage_iff (P : MorphismProperty D) (F : C ⥤ D) {X Y : C} (f : X ⟶ Y) :
P.inverseImage F f ↔ P (F.map f) := by rfl
def map (P : MorphismProperty C) (F : C ⥤ D) : MorphismProperty D := fun _ _ f =>
∃ (X' Y' : C) (f' : X' ⟶ Y') (_ : P f'), Nonempty (Arrow.mk (F.map f') ≅ Arrow.mk f)
lemma map_mem_map (P : MorphismProperty C) (F : C ⥤ D) {X Y : C} (f : X ⟶ Y) (hf : P f) :
(P.map F) (F.map f) := ⟨X, Y, f, hf, ⟨Iso.refl _⟩⟩
lemma monotone_map (F : C ⥤ D) :
Monotone (map · F) := by
intro P Q h X Y f ⟨X', Y', f', hf', ⟨e⟩⟩
exact ⟨X', Y', f', h _ hf', ⟨e⟩⟩
def RespectsIso (P : MorphismProperty C) : Prop :=
(∀ {X Y Z} (e : X ≅ Y) (f : Y ⟶ Z), P f → P (e.hom ≫ f)) ∧
∀ {X Y Z} (e : Y ≅ Z) (f : X ⟶ Y), P f → P (f ≫ e.hom)
#align category_theory.morphism_property.respects_iso CategoryTheory.MorphismProperty.RespectsIso
theorem RespectsIso.op {P : MorphismProperty C} (h : RespectsIso P) : RespectsIso P.op :=
⟨fun e f hf => h.2 e.unop f.unop hf, fun e f hf => h.1 e.unop f.unop hf⟩
#align category_theory.morphism_property.respects_iso.op CategoryTheory.MorphismProperty.RespectsIso.op
theorem RespectsIso.unop {P : MorphismProperty Cᵒᵖ} (h : RespectsIso P) : RespectsIso P.unop :=
⟨fun e f hf => h.2 e.op f.op hf, fun e f hf => h.1 e.op f.op hf⟩
#align category_theory.morphism_property.respects_iso.unop CategoryTheory.MorphismProperty.RespectsIso.unop
def isoClosure (P : MorphismProperty C) : MorphismProperty C :=
fun _ _ f => ∃ (Y₁ Y₂ : C) (f' : Y₁ ⟶ Y₂) (_ : P f'), Nonempty (Arrow.mk f' ≅ Arrow.mk f)
lemma le_isoClosure (P : MorphismProperty C) : P ≤ P.isoClosure :=
fun _ _ f hf => ⟨_, _, f, hf, ⟨Iso.refl _⟩⟩
lemma isoClosure_respectsIso (P : MorphismProperty C) :
RespectsIso P.isoClosure :=
⟨fun e f ⟨_, _, f', hf', ⟨iso⟩⟩ =>
⟨_, _, f', hf', ⟨Arrow.isoMk (asIso iso.hom.left ≪≫ e.symm)
(asIso iso.hom.right) (by simp)⟩⟩,
fun e f ⟨_, _, f', hf', ⟨iso⟩⟩ =>
⟨_, _, f', hf', ⟨Arrow.isoMk (asIso iso.hom.left)
(asIso iso.hom.right ≪≫ e) (by simp)⟩⟩⟩
lemma monotone_isoClosure : Monotone (isoClosure (C := C)) := by
intro P Q h X Y f ⟨X', Y', f', hf', ⟨e⟩⟩
exact ⟨X', Y', f', h _ hf', ⟨e⟩⟩
theorem RespectsIso.cancel_left_isIso {P : MorphismProperty C} (hP : RespectsIso P) {X Y Z : C}
(f : X ⟶ Y) (g : Y ⟶ Z) [IsIso f] : P (f ≫ g) ↔ P g :=
⟨fun h => by simpa using hP.1 (asIso f).symm (f ≫ g) h, hP.1 (asIso f) g⟩
#align category_theory.morphism_property.respects_iso.cancel_left_is_iso CategoryTheory.MorphismProperty.RespectsIso.cancel_left_isIso
theorem RespectsIso.cancel_right_isIso {P : MorphismProperty C} (hP : RespectsIso P) {X Y Z : C}
(f : X ⟶ Y) (g : Y ⟶ Z) [IsIso g] : P (f ≫ g) ↔ P f :=
⟨fun h => by simpa using hP.2 (asIso g).symm (f ≫ g) h, hP.2 (asIso g) f⟩
#align category_theory.morphism_property.respects_iso.cancel_right_is_iso CategoryTheory.MorphismProperty.RespectsIso.cancel_right_isIso
theorem RespectsIso.arrow_iso_iff {P : MorphismProperty C} (hP : RespectsIso P) {f g : Arrow C}
(e : f ≅ g) : P f.hom ↔ P g.hom := by
rw [← Arrow.inv_left_hom_right e.hom, hP.cancel_left_isIso, hP.cancel_right_isIso]
#align category_theory.morphism_property.respects_iso.arrow_iso_iff CategoryTheory.MorphismProperty.RespectsIso.arrow_iso_iff
theorem RespectsIso.arrow_mk_iso_iff {P : MorphismProperty C} (hP : RespectsIso P) {W X Y Z : C}
{f : W ⟶ X} {g : Y ⟶ Z} (e : Arrow.mk f ≅ Arrow.mk g) : P f ↔ P g :=
hP.arrow_iso_iff e
#align category_theory.morphism_property.respects_iso.arrow_mk_iso_iff CategoryTheory.MorphismProperty.RespectsIso.arrow_mk_iso_iff
theorem RespectsIso.of_respects_arrow_iso (P : MorphismProperty C)
(hP : ∀ (f g : Arrow C) (_ : f ≅ g) (_ : P f.hom), P g.hom) : RespectsIso P := by
constructor
· intro X Y Z e f hf
refine hP (Arrow.mk f) (Arrow.mk (e.hom ≫ f)) (Arrow.isoMk e.symm (Iso.refl _) ?_) hf
dsimp
simp only [Iso.inv_hom_id_assoc, Category.comp_id]
· intro X Y Z e f hf
refine hP (Arrow.mk f) (Arrow.mk (f ≫ e.hom)) (Arrow.isoMk (Iso.refl _) e ?_) hf
dsimp
simp only [Category.id_comp]
#align category_theory.morphism_property.respects_iso.of_respects_arrow_iso CategoryTheory.MorphismProperty.RespectsIso.of_respects_arrow_iso
lemma isoClosure_eq_iff {P : MorphismProperty C} :
P.isoClosure = P ↔ P.RespectsIso := by
refine ⟨(· ▸ P.isoClosure_respectsIso), fun hP ↦ le_antisymm ?_ (P.le_isoClosure)⟩
intro X Y f ⟨X', Y', f', hf', ⟨e⟩⟩
exact (hP.arrow_mk_iso_iff e).1 hf'
lemma RespectsIso.isoClosure_eq {P : MorphismProperty C} (hP : P.RespectsIso) :
P.isoClosure = P := by rwa [isoClosure_eq_iff]
@[simp]
lemma isoClosure_isoClosure (P : MorphismProperty C) :
P.isoClosure.isoClosure = P.isoClosure :=
P.isoClosure_respectsIso.isoClosure_eq
lemma isoClosure_le_iff (P Q : MorphismProperty C) (hQ : RespectsIso Q) :
P.isoClosure ≤ Q ↔ P ≤ Q := by
constructor
· exact P.le_isoClosure.trans
· intro h
exact (monotone_isoClosure h).trans (by rw [hQ.isoClosure_eq])
lemma map_respectsIso (P : MorphismProperty C) (F : C ⥤ D) :
(P.map F).RespectsIso := by
apply RespectsIso.of_respects_arrow_iso
intro f g e ⟨X', Y', f', hf', ⟨e'⟩⟩
exact ⟨X', Y', f', hf', ⟨e' ≪≫ e⟩⟩
lemma map_le_iff {P : MorphismProperty C} {F : C ⥤ D} {Q : MorphismProperty D}
(hQ : RespectsIso Q) :
P.map F ≤ Q ↔ P ≤ Q.inverseImage F := by
constructor
· intro h X Y f hf
exact h (F.map f) (map_mem_map P F f hf)
· intro h X Y f ⟨X', Y', f', hf', ⟨e⟩⟩
exact (hQ.arrow_mk_iso_iff e).1 (h _ hf')
@[simp]
lemma map_isoClosure (P : MorphismProperty C) (F : C ⥤ D) :
P.isoClosure.map F = P.map F := by
apply le_antisymm
· rw [map_le_iff (P.map_respectsIso F)]
intro X Y f ⟨X', Y', f', hf', ⟨e⟩⟩
exact ⟨_, _, f', hf', ⟨F.mapArrow.mapIso e⟩⟩
· exact monotone_map _ (le_isoClosure P)
lemma map_id_eq_isoClosure (P : MorphismProperty C) :
P.map (𝟭 _) = P.isoClosure := by
apply le_antisymm
· rw [map_le_iff P.isoClosure_respectsIso]
intro X Y f hf
exact P.le_isoClosure _ hf
· intro X Y f hf
exact hf
lemma map_id (P : MorphismProperty C) (hP : RespectsIso P) :
P.map (𝟭 _) = P := by
rw [map_id_eq_isoClosure, hP.isoClosure_eq]
@[simp]
lemma map_map (P : MorphismProperty C) (F : C ⥤ D) {E : Type*} [Category E] (G : D ⥤ E) :
(P.map F).map G = P.map (F ⋙ G) := by
apply le_antisymm
· rw [map_le_iff (map_respectsIso _ (F ⋙ G))]
intro X Y f ⟨X', Y', f', hf', ⟨e⟩⟩
exact ⟨X', Y', f', hf', ⟨G.mapArrow.mapIso e⟩⟩
· rw [map_le_iff (map_respectsIso _ G)]
intro X Y f hf
exact map_mem_map _ _ _ (map_mem_map _ _ _ hf)
theorem RespectsIso.inverseImage {P : MorphismProperty D} (h : RespectsIso P) (F : C ⥤ D) :
RespectsIso (P.inverseImage F) := by
constructor
all_goals
intro X Y Z e f hf
dsimp [MorphismProperty.inverseImage]
rw [F.map_comp]
exacts [h.1 (F.mapIso e) (F.map f) hf, h.2 (F.mapIso e) (F.map f) hf]
#align category_theory.morphism_property.respects_iso.inverse_image CategoryTheory.MorphismProperty.RespectsIso.inverseImage
lemma map_eq_of_iso (P : MorphismProperty C) {F G : C ⥤ D} (e : F ≅ G) :
P.map F = P.map G := by
revert F G e
suffices ∀ {F G : C ⥤ D} (_ : F ≅ G), P.map F ≤ P.map G from
fun F G e => le_antisymm (this e) (this e.symm)
intro F G e X Y f ⟨X', Y', f', hf', ⟨e'⟩⟩
exact ⟨X', Y', f', hf', ⟨((Functor.mapArrowFunctor _ _).mapIso e.symm).app (Arrow.mk f') ≪≫ e'⟩⟩
lemma map_inverseImage_le (P : MorphismProperty D) (F : C ⥤ D) :
(P.inverseImage F).map F ≤ P.isoClosure :=
fun _ _ _ ⟨_, _, f, hf, ⟨e⟩⟩ => ⟨_, _, F.map f, hf, ⟨e⟩⟩
lemma inverseImage_equivalence_inverse_eq_map_functor
(P : MorphismProperty D) (hP : RespectsIso P) (E : C ≌ D) :
P.inverseImage E.functor = P.map E.inverse := by
apply le_antisymm
· intro X Y f hf
refine ⟨_, _, _, hf, ⟨?_⟩⟩
exact ((Functor.mapArrowFunctor _ _).mapIso E.unitIso.symm).app (Arrow.mk f)
· rw [map_le_iff (hP.inverseImage E.functor)]
intro X Y f hf
exact (hP.arrow_mk_iso_iff
(((Functor.mapArrowFunctor _ _).mapIso E.counitIso).app (Arrow.mk f))).2 hf
lemma inverseImage_equivalence_functor_eq_map_inverse
(Q : MorphismProperty C) (hQ : RespectsIso Q) (E : C ≌ D) :
Q.inverseImage E.inverse = Q.map E.functor :=
inverseImage_equivalence_inverse_eq_map_functor Q hQ E.symm
lemma map_inverseImage_eq_of_isEquivalence
(P : MorphismProperty D) (hP : P.RespectsIso) (F : C ⥤ D) [F.IsEquivalence] :
(P.inverseImage F).map F = P := by
erw [P.inverseImage_equivalence_inverse_eq_map_functor hP F.asEquivalence, map_map,
P.map_eq_of_iso F.asEquivalence.counitIso, map_id _ hP]
lemma inverseImage_map_eq_of_isEquivalence
(P : MorphismProperty C) (hP : P.RespectsIso) (F : C ⥤ D) [F.IsEquivalence] :
(P.map F).inverseImage F = P := by
erw [((P.map F).inverseImage_equivalence_inverse_eq_map_functor
(P.map_respectsIso F) (F.asEquivalence)), map_map,
P.map_eq_of_iso F.asEquivalence.unitIso.symm, map_id _ hP]
variable (C)
def isomorphisms : MorphismProperty C := fun _ _ f => IsIso f
#align category_theory.morphism_property.isomorphisms CategoryTheory.MorphismProperty.isomorphisms
def monomorphisms : MorphismProperty C := fun _ _ f => Mono f
#align category_theory.morphism_property.monomorphisms CategoryTheory.MorphismProperty.monomorphisms
def epimorphisms : MorphismProperty C := fun _ _ f => Epi f
#align category_theory.morphism_property.epimorphisms CategoryTheory.MorphismProperty.epimorphisms
section
variable {C}
variable {X Y : C} (f : X ⟶ Y)
@[simp]
theorem isomorphisms.iff : (isomorphisms C) f ↔ IsIso f := by rfl
#align category_theory.morphism_property.isomorphisms.iff CategoryTheory.MorphismProperty.isomorphisms.iff
@[simp]
| Mathlib/CategoryTheory/MorphismProperty/Basic.lean | 317 | 317 | theorem monomorphisms.iff : (monomorphisms C) f ↔ Mono f := by | rfl
|
import Mathlib.Analysis.Convex.Side
import Mathlib.Geometry.Euclidean.Angle.Oriented.Rotation
import Mathlib.Geometry.Euclidean.Angle.Unoriented.Affine
#align_import geometry.euclidean.angle.oriented.affine from "leanprover-community/mathlib"@"46b633fd842bef9469441c0209906f6dddd2b4f5"
noncomputable section
open FiniteDimensional Complex
open scoped Affine EuclideanGeometry Real RealInnerProductSpace ComplexConjugate
namespace EuclideanGeometry
variable {V : Type*} {P : Type*} [NormedAddCommGroup V] [InnerProductSpace ℝ V] [MetricSpace P]
[NormedAddTorsor V P] [hd2 : Fact (finrank ℝ V = 2)] [Module.Oriented ℝ V (Fin 2)]
abbrev o := @Module.Oriented.positiveOrientation
def oangle (p₁ p₂ p₃ : P) : Real.Angle :=
o.oangle (p₁ -ᵥ p₂) (p₃ -ᵥ p₂)
#align euclidean_geometry.oangle EuclideanGeometry.oangle
@[inherit_doc] scoped notation "∡" => EuclideanGeometry.oangle
theorem continuousAt_oangle {x : P × P × P} (hx12 : x.1 ≠ x.2.1) (hx32 : x.2.2 ≠ x.2.1) :
ContinuousAt (fun y : P × P × P => ∡ y.1 y.2.1 y.2.2) x := by
let f : P × P × P → V × V := fun y => (y.1 -ᵥ y.2.1, y.2.2 -ᵥ y.2.1)
have hf1 : (f x).1 ≠ 0 := by simp [hx12]
have hf2 : (f x).2 ≠ 0 := by simp [hx32]
exact (o.continuousAt_oangle hf1 hf2).comp ((continuous_fst.vsub continuous_snd.fst).prod_mk
(continuous_snd.snd.vsub continuous_snd.fst)).continuousAt
#align euclidean_geometry.continuous_at_oangle EuclideanGeometry.continuousAt_oangle
@[simp]
theorem oangle_self_left (p₁ p₂ : P) : ∡ p₁ p₁ p₂ = 0 := by simp [oangle]
#align euclidean_geometry.oangle_self_left EuclideanGeometry.oangle_self_left
@[simp]
theorem oangle_self_right (p₁ p₂ : P) : ∡ p₁ p₂ p₂ = 0 := by simp [oangle]
#align euclidean_geometry.oangle_self_right EuclideanGeometry.oangle_self_right
@[simp]
theorem oangle_self_left_right (p₁ p₂ : P) : ∡ p₁ p₂ p₁ = 0 :=
o.oangle_self _
#align euclidean_geometry.oangle_self_left_right EuclideanGeometry.oangle_self_left_right
theorem left_ne_of_oangle_ne_zero {p₁ p₂ p₃ : P} (h : ∡ p₁ p₂ p₃ ≠ 0) : p₁ ≠ p₂ := by
rw [← @vsub_ne_zero V]; exact o.left_ne_zero_of_oangle_ne_zero h
#align euclidean_geometry.left_ne_of_oangle_ne_zero EuclideanGeometry.left_ne_of_oangle_ne_zero
theorem right_ne_of_oangle_ne_zero {p₁ p₂ p₃ : P} (h : ∡ p₁ p₂ p₃ ≠ 0) : p₃ ≠ p₂ := by
rw [← @vsub_ne_zero V]; exact o.right_ne_zero_of_oangle_ne_zero h
#align euclidean_geometry.right_ne_of_oangle_ne_zero EuclideanGeometry.right_ne_of_oangle_ne_zero
theorem left_ne_right_of_oangle_ne_zero {p₁ p₂ p₃ : P} (h : ∡ p₁ p₂ p₃ ≠ 0) : p₁ ≠ p₃ := by
rw [← (vsub_left_injective p₂).ne_iff]; exact o.ne_of_oangle_ne_zero h
#align euclidean_geometry.left_ne_right_of_oangle_ne_zero EuclideanGeometry.left_ne_right_of_oangle_ne_zero
theorem left_ne_of_oangle_eq_pi {p₁ p₂ p₃ : P} (h : ∡ p₁ p₂ p₃ = π) : p₁ ≠ p₂ :=
left_ne_of_oangle_ne_zero (h.symm ▸ Real.Angle.pi_ne_zero : ∡ p₁ p₂ p₃ ≠ 0)
#align euclidean_geometry.left_ne_of_oangle_eq_pi EuclideanGeometry.left_ne_of_oangle_eq_pi
theorem right_ne_of_oangle_eq_pi {p₁ p₂ p₃ : P} (h : ∡ p₁ p₂ p₃ = π) : p₃ ≠ p₂ :=
right_ne_of_oangle_ne_zero (h.symm ▸ Real.Angle.pi_ne_zero : ∡ p₁ p₂ p₃ ≠ 0)
#align euclidean_geometry.right_ne_of_oangle_eq_pi EuclideanGeometry.right_ne_of_oangle_eq_pi
theorem left_ne_right_of_oangle_eq_pi {p₁ p₂ p₃ : P} (h : ∡ p₁ p₂ p₃ = π) : p₁ ≠ p₃ :=
left_ne_right_of_oangle_ne_zero (h.symm ▸ Real.Angle.pi_ne_zero : ∡ p₁ p₂ p₃ ≠ 0)
#align euclidean_geometry.left_ne_right_of_oangle_eq_pi EuclideanGeometry.left_ne_right_of_oangle_eq_pi
theorem left_ne_of_oangle_eq_pi_div_two {p₁ p₂ p₃ : P} (h : ∡ p₁ p₂ p₃ = (π / 2 : ℝ)) : p₁ ≠ p₂ :=
left_ne_of_oangle_ne_zero (h.symm ▸ Real.Angle.pi_div_two_ne_zero : ∡ p₁ p₂ p₃ ≠ 0)
#align euclidean_geometry.left_ne_of_oangle_eq_pi_div_two EuclideanGeometry.left_ne_of_oangle_eq_pi_div_two
theorem right_ne_of_oangle_eq_pi_div_two {p₁ p₂ p₃ : P} (h : ∡ p₁ p₂ p₃ = (π / 2 : ℝ)) : p₃ ≠ p₂ :=
right_ne_of_oangle_ne_zero (h.symm ▸ Real.Angle.pi_div_two_ne_zero : ∡ p₁ p₂ p₃ ≠ 0)
#align euclidean_geometry.right_ne_of_oangle_eq_pi_div_two EuclideanGeometry.right_ne_of_oangle_eq_pi_div_two
theorem left_ne_right_of_oangle_eq_pi_div_two {p₁ p₂ p₃ : P} (h : ∡ p₁ p₂ p₃ = (π / 2 : ℝ)) :
p₁ ≠ p₃ :=
left_ne_right_of_oangle_ne_zero (h.symm ▸ Real.Angle.pi_div_two_ne_zero : ∡ p₁ p₂ p₃ ≠ 0)
#align euclidean_geometry.left_ne_right_of_oangle_eq_pi_div_two EuclideanGeometry.left_ne_right_of_oangle_eq_pi_div_two
theorem left_ne_of_oangle_eq_neg_pi_div_two {p₁ p₂ p₃ : P} (h : ∡ p₁ p₂ p₃ = (-π / 2 : ℝ)) :
p₁ ≠ p₂ :=
left_ne_of_oangle_ne_zero (h.symm ▸ Real.Angle.neg_pi_div_two_ne_zero : ∡ p₁ p₂ p₃ ≠ 0)
#align euclidean_geometry.left_ne_of_oangle_eq_neg_pi_div_two EuclideanGeometry.left_ne_of_oangle_eq_neg_pi_div_two
theorem right_ne_of_oangle_eq_neg_pi_div_two {p₁ p₂ p₃ : P} (h : ∡ p₁ p₂ p₃ = (-π / 2 : ℝ)) :
p₃ ≠ p₂ :=
right_ne_of_oangle_ne_zero (h.symm ▸ Real.Angle.neg_pi_div_two_ne_zero : ∡ p₁ p₂ p₃ ≠ 0)
#align euclidean_geometry.right_ne_of_oangle_eq_neg_pi_div_two EuclideanGeometry.right_ne_of_oangle_eq_neg_pi_div_two
theorem left_ne_right_of_oangle_eq_neg_pi_div_two {p₁ p₂ p₃ : P} (h : ∡ p₁ p₂ p₃ = (-π / 2 : ℝ)) :
p₁ ≠ p₃ :=
left_ne_right_of_oangle_ne_zero (h.symm ▸ Real.Angle.neg_pi_div_two_ne_zero : ∡ p₁ p₂ p₃ ≠ 0)
#align euclidean_geometry.left_ne_right_of_oangle_eq_neg_pi_div_two EuclideanGeometry.left_ne_right_of_oangle_eq_neg_pi_div_two
theorem left_ne_of_oangle_sign_ne_zero {p₁ p₂ p₃ : P} (h : (∡ p₁ p₂ p₃).sign ≠ 0) : p₁ ≠ p₂ :=
left_ne_of_oangle_ne_zero (Real.Angle.sign_ne_zero_iff.1 h).1
#align euclidean_geometry.left_ne_of_oangle_sign_ne_zero EuclideanGeometry.left_ne_of_oangle_sign_ne_zero
theorem right_ne_of_oangle_sign_ne_zero {p₁ p₂ p₃ : P} (h : (∡ p₁ p₂ p₃).sign ≠ 0) : p₃ ≠ p₂ :=
right_ne_of_oangle_ne_zero (Real.Angle.sign_ne_zero_iff.1 h).1
#align euclidean_geometry.right_ne_of_oangle_sign_ne_zero EuclideanGeometry.right_ne_of_oangle_sign_ne_zero
theorem left_ne_right_of_oangle_sign_ne_zero {p₁ p₂ p₃ : P} (h : (∡ p₁ p₂ p₃).sign ≠ 0) : p₁ ≠ p₃ :=
left_ne_right_of_oangle_ne_zero (Real.Angle.sign_ne_zero_iff.1 h).1
#align euclidean_geometry.left_ne_right_of_oangle_sign_ne_zero EuclideanGeometry.left_ne_right_of_oangle_sign_ne_zero
theorem left_ne_of_oangle_sign_eq_one {p₁ p₂ p₃ : P} (h : (∡ p₁ p₂ p₃).sign = 1) : p₁ ≠ p₂ :=
left_ne_of_oangle_sign_ne_zero (h.symm ▸ by decide : (∡ p₁ p₂ p₃).sign ≠ 0)
#align euclidean_geometry.left_ne_of_oangle_sign_eq_one EuclideanGeometry.left_ne_of_oangle_sign_eq_one
theorem right_ne_of_oangle_sign_eq_one {p₁ p₂ p₃ : P} (h : (∡ p₁ p₂ p₃).sign = 1) : p₃ ≠ p₂ :=
right_ne_of_oangle_sign_ne_zero (h.symm ▸ by decide : (∡ p₁ p₂ p₃).sign ≠ 0)
#align euclidean_geometry.right_ne_of_oangle_sign_eq_one EuclideanGeometry.right_ne_of_oangle_sign_eq_one
theorem left_ne_right_of_oangle_sign_eq_one {p₁ p₂ p₃ : P} (h : (∡ p₁ p₂ p₃).sign = 1) : p₁ ≠ p₃ :=
left_ne_right_of_oangle_sign_ne_zero (h.symm ▸ by decide : (∡ p₁ p₂ p₃).sign ≠ 0)
#align euclidean_geometry.left_ne_right_of_oangle_sign_eq_one EuclideanGeometry.left_ne_right_of_oangle_sign_eq_one
theorem left_ne_of_oangle_sign_eq_neg_one {p₁ p₂ p₃ : P} (h : (∡ p₁ p₂ p₃).sign = -1) : p₁ ≠ p₂ :=
left_ne_of_oangle_sign_ne_zero (h.symm ▸ by decide : (∡ p₁ p₂ p₃).sign ≠ 0)
#align euclidean_geometry.left_ne_of_oangle_sign_eq_neg_one EuclideanGeometry.left_ne_of_oangle_sign_eq_neg_one
theorem right_ne_of_oangle_sign_eq_neg_one {p₁ p₂ p₃ : P} (h : (∡ p₁ p₂ p₃).sign = -1) : p₃ ≠ p₂ :=
right_ne_of_oangle_sign_ne_zero (h.symm ▸ by decide : (∡ p₁ p₂ p₃).sign ≠ 0)
#align euclidean_geometry.right_ne_of_oangle_sign_eq_neg_one EuclideanGeometry.right_ne_of_oangle_sign_eq_neg_one
theorem left_ne_right_of_oangle_sign_eq_neg_one {p₁ p₂ p₃ : P} (h : (∡ p₁ p₂ p₃).sign = -1) :
p₁ ≠ p₃ :=
left_ne_right_of_oangle_sign_ne_zero (h.symm ▸ by decide : (∡ p₁ p₂ p₃).sign ≠ 0)
#align euclidean_geometry.left_ne_right_of_oangle_sign_eq_neg_one EuclideanGeometry.left_ne_right_of_oangle_sign_eq_neg_one
theorem oangle_rev (p₁ p₂ p₃ : P) : ∡ p₃ p₂ p₁ = -∡ p₁ p₂ p₃ :=
o.oangle_rev _ _
#align euclidean_geometry.oangle_rev EuclideanGeometry.oangle_rev
@[simp]
theorem oangle_add_oangle_rev (p₁ p₂ p₃ : P) : ∡ p₁ p₂ p₃ + ∡ p₃ p₂ p₁ = 0 :=
o.oangle_add_oangle_rev _ _
#align euclidean_geometry.oangle_add_oangle_rev EuclideanGeometry.oangle_add_oangle_rev
theorem oangle_eq_zero_iff_oangle_rev_eq_zero {p₁ p₂ p₃ : P} : ∡ p₁ p₂ p₃ = 0 ↔ ∡ p₃ p₂ p₁ = 0 :=
o.oangle_eq_zero_iff_oangle_rev_eq_zero
#align euclidean_geometry.oangle_eq_zero_iff_oangle_rev_eq_zero EuclideanGeometry.oangle_eq_zero_iff_oangle_rev_eq_zero
theorem oangle_eq_pi_iff_oangle_rev_eq_pi {p₁ p₂ p₃ : P} : ∡ p₁ p₂ p₃ = π ↔ ∡ p₃ p₂ p₁ = π :=
o.oangle_eq_pi_iff_oangle_rev_eq_pi
#align euclidean_geometry.oangle_eq_pi_iff_oangle_rev_eq_pi EuclideanGeometry.oangle_eq_pi_iff_oangle_rev_eq_pi
theorem oangle_ne_zero_and_ne_pi_iff_affineIndependent {p₁ p₂ p₃ : P} :
∡ p₁ p₂ p₃ ≠ 0 ∧ ∡ p₁ p₂ p₃ ≠ π ↔ AffineIndependent ℝ ![p₁, p₂, p₃] := by
rw [oangle, o.oangle_ne_zero_and_ne_pi_iff_linearIndependent,
affineIndependent_iff_linearIndependent_vsub ℝ _ (1 : Fin 3), ←
linearIndependent_equiv (finSuccAboveEquiv (1 : Fin 3)).toEquiv]
convert Iff.rfl
ext i
fin_cases i <;> rfl
#align euclidean_geometry.oangle_ne_zero_and_ne_pi_iff_affine_independent EuclideanGeometry.oangle_ne_zero_and_ne_pi_iff_affineIndependent
theorem oangle_eq_zero_or_eq_pi_iff_collinear {p₁ p₂ p₃ : P} :
∡ p₁ p₂ p₃ = 0 ∨ ∡ p₁ p₂ p₃ = π ↔ Collinear ℝ ({p₁, p₂, p₃} : Set P) := by
rw [← not_iff_not, not_or, oangle_ne_zero_and_ne_pi_iff_affineIndependent,
affineIndependent_iff_not_collinear_set]
#align euclidean_geometry.oangle_eq_zero_or_eq_pi_iff_collinear EuclideanGeometry.oangle_eq_zero_or_eq_pi_iff_collinear
theorem oangle_sign_eq_zero_iff_collinear {p₁ p₂ p₃ : P} :
(∡ p₁ p₂ p₃).sign = 0 ↔ Collinear ℝ ({p₁, p₂, p₃} : Set P) := by
rw [Real.Angle.sign_eq_zero_iff, oangle_eq_zero_or_eq_pi_iff_collinear]
theorem affineIndependent_iff_of_two_zsmul_oangle_eq {p₁ p₂ p₃ p₄ p₅ p₆ : P}
(h : (2 : ℤ) • ∡ p₁ p₂ p₃ = (2 : ℤ) • ∡ p₄ p₅ p₆) :
AffineIndependent ℝ ![p₁, p₂, p₃] ↔ AffineIndependent ℝ ![p₄, p₅, p₆] := by
simp_rw [← oangle_ne_zero_and_ne_pi_iff_affineIndependent, ← Real.Angle.two_zsmul_ne_zero_iff, h]
#align euclidean_geometry.affine_independent_iff_of_two_zsmul_oangle_eq EuclideanGeometry.affineIndependent_iff_of_two_zsmul_oangle_eq
theorem collinear_iff_of_two_zsmul_oangle_eq {p₁ p₂ p₃ p₄ p₅ p₆ : P}
(h : (2 : ℤ) • ∡ p₁ p₂ p₃ = (2 : ℤ) • ∡ p₄ p₅ p₆) :
Collinear ℝ ({p₁, p₂, p₃} : Set P) ↔ Collinear ℝ ({p₄, p₅, p₆} : Set P) := by
simp_rw [← oangle_eq_zero_or_eq_pi_iff_collinear, ← Real.Angle.two_zsmul_eq_zero_iff, h]
#align euclidean_geometry.collinear_iff_of_two_zsmul_oangle_eq EuclideanGeometry.collinear_iff_of_two_zsmul_oangle_eq
theorem two_zsmul_oangle_of_vectorSpan_eq {p₁ p₂ p₃ p₄ p₅ p₆ : P}
(h₁₂₄₅ : vectorSpan ℝ ({p₁, p₂} : Set P) = vectorSpan ℝ ({p₄, p₅} : Set P))
(h₃₂₆₅ : vectorSpan ℝ ({p₃, p₂} : Set P) = vectorSpan ℝ ({p₆, p₅} : Set P)) :
(2 : ℤ) • ∡ p₁ p₂ p₃ = (2 : ℤ) • ∡ p₄ p₅ p₆ := by
simp_rw [vectorSpan_pair] at h₁₂₄₅ h₃₂₆₅
exact o.two_zsmul_oangle_of_span_eq_of_span_eq h₁₂₄₅ h₃₂₆₅
#align euclidean_geometry.two_zsmul_oangle_of_vector_span_eq EuclideanGeometry.two_zsmul_oangle_of_vectorSpan_eq
theorem two_zsmul_oangle_of_parallel {p₁ p₂ p₃ p₄ p₅ p₆ : P}
(h₁₂₄₅ : line[ℝ, p₁, p₂] ∥ line[ℝ, p₄, p₅]) (h₃₂₆₅ : line[ℝ, p₃, p₂] ∥ line[ℝ, p₆, p₅]) :
(2 : ℤ) • ∡ p₁ p₂ p₃ = (2 : ℤ) • ∡ p₄ p₅ p₆ := by
rw [AffineSubspace.affineSpan_pair_parallel_iff_vectorSpan_eq] at h₁₂₄₅ h₃₂₆₅
exact two_zsmul_oangle_of_vectorSpan_eq h₁₂₄₅ h₃₂₆₅
#align euclidean_geometry.two_zsmul_oangle_of_parallel EuclideanGeometry.two_zsmul_oangle_of_parallel
@[simp]
theorem oangle_add {p p₁ p₂ p₃ : P} (hp₁ : p₁ ≠ p) (hp₂ : p₂ ≠ p) (hp₃ : p₃ ≠ p) :
∡ p₁ p p₂ + ∡ p₂ p p₃ = ∡ p₁ p p₃ :=
o.oangle_add (vsub_ne_zero.2 hp₁) (vsub_ne_zero.2 hp₂) (vsub_ne_zero.2 hp₃)
#align euclidean_geometry.oangle_add EuclideanGeometry.oangle_add
@[simp]
theorem oangle_add_swap {p p₁ p₂ p₃ : P} (hp₁ : p₁ ≠ p) (hp₂ : p₂ ≠ p) (hp₃ : p₃ ≠ p) :
∡ p₂ p p₃ + ∡ p₁ p p₂ = ∡ p₁ p p₃ :=
o.oangle_add_swap (vsub_ne_zero.2 hp₁) (vsub_ne_zero.2 hp₂) (vsub_ne_zero.2 hp₃)
#align euclidean_geometry.oangle_add_swap EuclideanGeometry.oangle_add_swap
@[simp]
theorem oangle_sub_left {p p₁ p₂ p₃ : P} (hp₁ : p₁ ≠ p) (hp₂ : p₂ ≠ p) (hp₃ : p₃ ≠ p) :
∡ p₁ p p₃ - ∡ p₁ p p₂ = ∡ p₂ p p₃ :=
o.oangle_sub_left (vsub_ne_zero.2 hp₁) (vsub_ne_zero.2 hp₂) (vsub_ne_zero.2 hp₃)
#align euclidean_geometry.oangle_sub_left EuclideanGeometry.oangle_sub_left
@[simp]
theorem oangle_sub_right {p p₁ p₂ p₃ : P} (hp₁ : p₁ ≠ p) (hp₂ : p₂ ≠ p) (hp₃ : p₃ ≠ p) :
∡ p₁ p p₃ - ∡ p₂ p p₃ = ∡ p₁ p p₂ :=
o.oangle_sub_right (vsub_ne_zero.2 hp₁) (vsub_ne_zero.2 hp₂) (vsub_ne_zero.2 hp₃)
#align euclidean_geometry.oangle_sub_right EuclideanGeometry.oangle_sub_right
@[simp]
theorem oangle_add_cyc3 {p p₁ p₂ p₃ : P} (hp₁ : p₁ ≠ p) (hp₂ : p₂ ≠ p) (hp₃ : p₃ ≠ p) :
∡ p₁ p p₂ + ∡ p₂ p p₃ + ∡ p₃ p p₁ = 0 :=
o.oangle_add_cyc3 (vsub_ne_zero.2 hp₁) (vsub_ne_zero.2 hp₂) (vsub_ne_zero.2 hp₃)
#align euclidean_geometry.oangle_add_cyc3 EuclideanGeometry.oangle_add_cyc3
theorem oangle_eq_oangle_of_dist_eq {p₁ p₂ p₃ : P} (h : dist p₁ p₂ = dist p₁ p₃) :
∡ p₁ p₂ p₃ = ∡ p₂ p₃ p₁ := by
simp_rw [dist_eq_norm_vsub V] at h
rw [oangle, oangle, ← vsub_sub_vsub_cancel_left p₃ p₂ p₁, ← vsub_sub_vsub_cancel_left p₂ p₃ p₁,
o.oangle_sub_eq_oangle_sub_rev_of_norm_eq h]
#align euclidean_geometry.oangle_eq_oangle_of_dist_eq EuclideanGeometry.oangle_eq_oangle_of_dist_eq
theorem oangle_eq_pi_sub_two_zsmul_oangle_of_dist_eq {p₁ p₂ p₃ : P} (hn : p₂ ≠ p₃)
(h : dist p₁ p₂ = dist p₁ p₃) : ∡ p₃ p₁ p₂ = π - (2 : ℤ) • ∡ p₁ p₂ p₃ := by
simp_rw [dist_eq_norm_vsub V] at h
rw [oangle, oangle]
convert o.oangle_eq_pi_sub_two_zsmul_oangle_sub_of_norm_eq _ h using 1
· rw [← neg_vsub_eq_vsub_rev p₁ p₃, ← neg_vsub_eq_vsub_rev p₁ p₂, o.oangle_neg_neg]
· rw [← o.oangle_sub_eq_oangle_sub_rev_of_norm_eq h]; simp
· simpa using hn
#align euclidean_geometry.oangle_eq_pi_sub_two_zsmul_oangle_of_dist_eq EuclideanGeometry.oangle_eq_pi_sub_two_zsmul_oangle_of_dist_eq
theorem abs_oangle_right_toReal_lt_pi_div_two_of_dist_eq {p₁ p₂ p₃ : P}
(h : dist p₁ p₂ = dist p₁ p₃) : |(∡ p₁ p₂ p₃).toReal| < π / 2 := by
simp_rw [dist_eq_norm_vsub V] at h
rw [oangle, ← vsub_sub_vsub_cancel_left p₃ p₂ p₁]
exact o.abs_oangle_sub_right_toReal_lt_pi_div_two h
#align euclidean_geometry.abs_oangle_right_to_real_lt_pi_div_two_of_dist_eq EuclideanGeometry.abs_oangle_right_toReal_lt_pi_div_two_of_dist_eq
theorem abs_oangle_left_toReal_lt_pi_div_two_of_dist_eq {p₁ p₂ p₃ : P}
(h : dist p₁ p₂ = dist p₁ p₃) : |(∡ p₂ p₃ p₁).toReal| < π / 2 :=
oangle_eq_oangle_of_dist_eq h ▸ abs_oangle_right_toReal_lt_pi_div_two_of_dist_eq h
#align euclidean_geometry.abs_oangle_left_to_real_lt_pi_div_two_of_dist_eq EuclideanGeometry.abs_oangle_left_toReal_lt_pi_div_two_of_dist_eq
theorem cos_oangle_eq_cos_angle {p p₁ p₂ : P} (hp₁ : p₁ ≠ p) (hp₂ : p₂ ≠ p) :
Real.Angle.cos (∡ p₁ p p₂) = Real.cos (∠ p₁ p p₂) :=
o.cos_oangle_eq_cos_angle (vsub_ne_zero.2 hp₁) (vsub_ne_zero.2 hp₂)
#align euclidean_geometry.cos_oangle_eq_cos_angle EuclideanGeometry.cos_oangle_eq_cos_angle
theorem oangle_eq_angle_or_eq_neg_angle {p p₁ p₂ : P} (hp₁ : p₁ ≠ p) (hp₂ : p₂ ≠ p) :
∡ p₁ p p₂ = ∠ p₁ p p₂ ∨ ∡ p₁ p p₂ = -∠ p₁ p p₂ :=
o.oangle_eq_angle_or_eq_neg_angle (vsub_ne_zero.2 hp₁) (vsub_ne_zero.2 hp₂)
#align euclidean_geometry.oangle_eq_angle_or_eq_neg_angle EuclideanGeometry.oangle_eq_angle_or_eq_neg_angle
theorem angle_eq_abs_oangle_toReal {p p₁ p₂ : P} (hp₁ : p₁ ≠ p) (hp₂ : p₂ ≠ p) :
∠ p₁ p p₂ = |(∡ p₁ p p₂).toReal| :=
o.angle_eq_abs_oangle_toReal (vsub_ne_zero.2 hp₁) (vsub_ne_zero.2 hp₂)
#align euclidean_geometry.angle_eq_abs_oangle_to_real EuclideanGeometry.angle_eq_abs_oangle_toReal
theorem eq_zero_or_angle_eq_zero_or_pi_of_sign_oangle_eq_zero {p p₁ p₂ : P}
(h : (∡ p₁ p p₂).sign = 0) : p₁ = p ∨ p₂ = p ∨ ∠ p₁ p p₂ = 0 ∨ ∠ p₁ p p₂ = π := by
convert o.eq_zero_or_angle_eq_zero_or_pi_of_sign_oangle_eq_zero h <;> simp
#align euclidean_geometry.eq_zero_or_angle_eq_zero_or_pi_of_sign_oangle_eq_zero EuclideanGeometry.eq_zero_or_angle_eq_zero_or_pi_of_sign_oangle_eq_zero
theorem oangle_eq_of_angle_eq_of_sign_eq {p₁ p₂ p₃ p₄ p₅ p₆ : P} (h : ∠ p₁ p₂ p₃ = ∠ p₄ p₅ p₆)
(hs : (∡ p₁ p₂ p₃).sign = (∡ p₄ p₅ p₆).sign) : ∡ p₁ p₂ p₃ = ∡ p₄ p₅ p₆ :=
o.oangle_eq_of_angle_eq_of_sign_eq h hs
#align euclidean_geometry.oangle_eq_of_angle_eq_of_sign_eq EuclideanGeometry.oangle_eq_of_angle_eq_of_sign_eq
theorem angle_eq_iff_oangle_eq_of_sign_eq {p₁ p₂ p₃ p₄ p₅ p₆ : P} (hp₁ : p₁ ≠ p₂) (hp₃ : p₃ ≠ p₂)
(hp₄ : p₄ ≠ p₅) (hp₆ : p₆ ≠ p₅) (hs : (∡ p₁ p₂ p₃).sign = (∡ p₄ p₅ p₆).sign) :
∠ p₁ p₂ p₃ = ∠ p₄ p₅ p₆ ↔ ∡ p₁ p₂ p₃ = ∡ p₄ p₅ p₆ :=
o.angle_eq_iff_oangle_eq_of_sign_eq (vsub_ne_zero.2 hp₁) (vsub_ne_zero.2 hp₃) (vsub_ne_zero.2 hp₄)
(vsub_ne_zero.2 hp₆) hs
#align euclidean_geometry.angle_eq_iff_oangle_eq_of_sign_eq EuclideanGeometry.angle_eq_iff_oangle_eq_of_sign_eq
theorem oangle_eq_angle_of_sign_eq_one {p₁ p₂ p₃ : P} (h : (∡ p₁ p₂ p₃).sign = 1) :
∡ p₁ p₂ p₃ = ∠ p₁ p₂ p₃ :=
o.oangle_eq_angle_of_sign_eq_one h
#align euclidean_geometry.oangle_eq_angle_of_sign_eq_one EuclideanGeometry.oangle_eq_angle_of_sign_eq_one
theorem oangle_eq_neg_angle_of_sign_eq_neg_one {p₁ p₂ p₃ : P} (h : (∡ p₁ p₂ p₃).sign = -1) :
∡ p₁ p₂ p₃ = -∠ p₁ p₂ p₃ :=
o.oangle_eq_neg_angle_of_sign_eq_neg_one h
#align euclidean_geometry.oangle_eq_neg_angle_of_sign_eq_neg_one EuclideanGeometry.oangle_eq_neg_angle_of_sign_eq_neg_one
theorem oangle_eq_zero_iff_angle_eq_zero {p p₁ p₂ : P} (hp₁ : p₁ ≠ p) (hp₂ : p₂ ≠ p) :
∡ p₁ p p₂ = 0 ↔ ∠ p₁ p p₂ = 0 :=
o.oangle_eq_zero_iff_angle_eq_zero (vsub_ne_zero.2 hp₁) (vsub_ne_zero.2 hp₂)
#align euclidean_geometry.oangle_eq_zero_iff_angle_eq_zero EuclideanGeometry.oangle_eq_zero_iff_angle_eq_zero
theorem oangle_eq_pi_iff_angle_eq_pi {p₁ p₂ p₃ : P} : ∡ p₁ p₂ p₃ = π ↔ ∠ p₁ p₂ p₃ = π :=
o.oangle_eq_pi_iff_angle_eq_pi
#align euclidean_geometry.oangle_eq_pi_iff_angle_eq_pi EuclideanGeometry.oangle_eq_pi_iff_angle_eq_pi
theorem angle_eq_pi_div_two_of_oangle_eq_pi_div_two {p₁ p₂ p₃ : P} (h : ∡ p₁ p₂ p₃ = ↑(π / 2)) :
∠ p₁ p₂ p₃ = π / 2 := by
rw [angle, ← InnerProductGeometry.inner_eq_zero_iff_angle_eq_pi_div_two]
exact o.inner_eq_zero_of_oangle_eq_pi_div_two h
#align euclidean_geometry.angle_eq_pi_div_two_of_oangle_eq_pi_div_two EuclideanGeometry.angle_eq_pi_div_two_of_oangle_eq_pi_div_two
theorem angle_rev_eq_pi_div_two_of_oangle_eq_pi_div_two {p₁ p₂ p₃ : P} (h : ∡ p₁ p₂ p₃ = ↑(π / 2)) :
∠ p₃ p₂ p₁ = π / 2 := by
rw [angle_comm]
exact angle_eq_pi_div_two_of_oangle_eq_pi_div_two h
#align euclidean_geometry.angle_rev_eq_pi_div_two_of_oangle_eq_pi_div_two EuclideanGeometry.angle_rev_eq_pi_div_two_of_oangle_eq_pi_div_two
theorem angle_eq_pi_div_two_of_oangle_eq_neg_pi_div_two {p₁ p₂ p₃ : P}
(h : ∡ p₁ p₂ p₃ = ↑(-π / 2)) : ∠ p₁ p₂ p₃ = π / 2 := by
rw [angle, ← InnerProductGeometry.inner_eq_zero_iff_angle_eq_pi_div_two]
exact o.inner_eq_zero_of_oangle_eq_neg_pi_div_two h
#align euclidean_geometry.angle_eq_pi_div_two_of_oangle_eq_neg_pi_div_two EuclideanGeometry.angle_eq_pi_div_two_of_oangle_eq_neg_pi_div_two
theorem angle_rev_eq_pi_div_two_of_oangle_eq_neg_pi_div_two {p₁ p₂ p₃ : P}
(h : ∡ p₁ p₂ p₃ = ↑(-π / 2)) : ∠ p₃ p₂ p₁ = π / 2 := by
rw [angle_comm]
exact angle_eq_pi_div_two_of_oangle_eq_neg_pi_div_two h
#align euclidean_geometry.angle_rev_eq_pi_div_two_of_oangle_eq_neg_pi_div_two EuclideanGeometry.angle_rev_eq_pi_div_two_of_oangle_eq_neg_pi_div_two
theorem oangle_swap₁₂_sign (p₁ p₂ p₃ : P) : -(∡ p₁ p₂ p₃).sign = (∡ p₂ p₁ p₃).sign := by
rw [eq_comm, oangle, oangle, ← o.oangle_neg_neg, neg_vsub_eq_vsub_rev, neg_vsub_eq_vsub_rev, ←
vsub_sub_vsub_cancel_left p₁ p₃ p₂, ← neg_vsub_eq_vsub_rev p₃ p₂, sub_eq_add_neg,
neg_vsub_eq_vsub_rev p₂ p₁, add_comm, ← @neg_one_smul ℝ]
nth_rw 2 [← one_smul ℝ (p₁ -ᵥ p₂)]
rw [o.oangle_sign_smul_add_smul_right]
simp
#align euclidean_geometry.oangle_swap₁₂_sign EuclideanGeometry.oangle_swap₁₂_sign
theorem oangle_swap₁₃_sign (p₁ p₂ p₃ : P) : -(∡ p₁ p₂ p₃).sign = (∡ p₃ p₂ p₁).sign := by
rw [oangle_rev, Real.Angle.sign_neg, neg_neg]
#align euclidean_geometry.oangle_swap₁₃_sign EuclideanGeometry.oangle_swap₁₃_sign
theorem oangle_swap₂₃_sign (p₁ p₂ p₃ : P) : -(∡ p₁ p₂ p₃).sign = (∡ p₁ p₃ p₂).sign := by
rw [oangle_swap₁₃_sign, ← oangle_swap₁₂_sign, oangle_swap₁₃_sign]
#align euclidean_geometry.oangle_swap₂₃_sign EuclideanGeometry.oangle_swap₂₃_sign
theorem oangle_rotate_sign (p₁ p₂ p₃ : P) : (∡ p₂ p₃ p₁).sign = (∡ p₁ p₂ p₃).sign := by
rw [← oangle_swap₁₂_sign, oangle_swap₁₃_sign]
#align euclidean_geometry.oangle_rotate_sign EuclideanGeometry.oangle_rotate_sign
theorem oangle_eq_pi_iff_sbtw {p₁ p₂ p₃ : P} : ∡ p₁ p₂ p₃ = π ↔ Sbtw ℝ p₁ p₂ p₃ := by
rw [oangle_eq_pi_iff_angle_eq_pi, angle_eq_pi_iff_sbtw]
#align euclidean_geometry.oangle_eq_pi_iff_sbtw EuclideanGeometry.oangle_eq_pi_iff_sbtw
theorem _root_.Sbtw.oangle₁₂₃_eq_pi {p₁ p₂ p₃ : P} (h : Sbtw ℝ p₁ p₂ p₃) : ∡ p₁ p₂ p₃ = π :=
oangle_eq_pi_iff_sbtw.2 h
#align sbtw.oangle₁₂₃_eq_pi Sbtw.oangle₁₂₃_eq_pi
theorem _root_.Sbtw.oangle₃₂₁_eq_pi {p₁ p₂ p₃ : P} (h : Sbtw ℝ p₁ p₂ p₃) : ∡ p₃ p₂ p₁ = π := by
rw [oangle_eq_pi_iff_oangle_rev_eq_pi, ← h.oangle₁₂₃_eq_pi]
#align sbtw.oangle₃₂₁_eq_pi Sbtw.oangle₃₂₁_eq_pi
theorem _root_.Wbtw.oangle₂₁₃_eq_zero {p₁ p₂ p₃ : P} (h : Wbtw ℝ p₁ p₂ p₃) : ∡ p₂ p₁ p₃ = 0 := by
by_cases hp₂p₁ : p₂ = p₁; · simp [hp₂p₁]
by_cases hp₃p₁ : p₃ = p₁; · simp [hp₃p₁]
rw [oangle_eq_zero_iff_angle_eq_zero hp₂p₁ hp₃p₁]
exact h.angle₂₁₃_eq_zero_of_ne hp₂p₁
#align wbtw.oangle₂₁₃_eq_zero Wbtw.oangle₂₁₃_eq_zero
theorem _root_.Sbtw.oangle₂₁₃_eq_zero {p₁ p₂ p₃ : P} (h : Sbtw ℝ p₁ p₂ p₃) : ∡ p₂ p₁ p₃ = 0 :=
h.wbtw.oangle₂₁₃_eq_zero
#align sbtw.oangle₂₁₃_eq_zero Sbtw.oangle₂₁₃_eq_zero
theorem _root_.Wbtw.oangle₃₁₂_eq_zero {p₁ p₂ p₃ : P} (h : Wbtw ℝ p₁ p₂ p₃) : ∡ p₃ p₁ p₂ = 0 := by
rw [oangle_eq_zero_iff_oangle_rev_eq_zero, h.oangle₂₁₃_eq_zero]
#align wbtw.oangle₃₁₂_eq_zero Wbtw.oangle₃₁₂_eq_zero
theorem _root_.Sbtw.oangle₃₁₂_eq_zero {p₁ p₂ p₃ : P} (h : Sbtw ℝ p₁ p₂ p₃) : ∡ p₃ p₁ p₂ = 0 :=
h.wbtw.oangle₃₁₂_eq_zero
#align sbtw.oangle₃₁₂_eq_zero Sbtw.oangle₃₁₂_eq_zero
theorem _root_.Wbtw.oangle₂₃₁_eq_zero {p₁ p₂ p₃ : P} (h : Wbtw ℝ p₁ p₂ p₃) : ∡ p₂ p₃ p₁ = 0 :=
h.symm.oangle₂₁₃_eq_zero
#align wbtw.oangle₂₃₁_eq_zero Wbtw.oangle₂₃₁_eq_zero
theorem _root_.Sbtw.oangle₂₃₁_eq_zero {p₁ p₂ p₃ : P} (h : Sbtw ℝ p₁ p₂ p₃) : ∡ p₂ p₃ p₁ = 0 :=
h.wbtw.oangle₂₃₁_eq_zero
#align sbtw.oangle₂₃₁_eq_zero Sbtw.oangle₂₃₁_eq_zero
theorem _root_.Wbtw.oangle₁₃₂_eq_zero {p₁ p₂ p₃ : P} (h : Wbtw ℝ p₁ p₂ p₃) : ∡ p₁ p₃ p₂ = 0 :=
h.symm.oangle₃₁₂_eq_zero
#align wbtw.oangle₁₃₂_eq_zero Wbtw.oangle₁₃₂_eq_zero
theorem _root_.Sbtw.oangle₁₃₂_eq_zero {p₁ p₂ p₃ : P} (h : Sbtw ℝ p₁ p₂ p₃) : ∡ p₁ p₃ p₂ = 0 :=
h.wbtw.oangle₁₃₂_eq_zero
#align sbtw.oangle₁₃₂_eq_zero Sbtw.oangle₁₃₂_eq_zero
theorem oangle_eq_zero_iff_wbtw {p₁ p₂ p₃ : P} :
∡ p₁ p₂ p₃ = 0 ↔ Wbtw ℝ p₂ p₁ p₃ ∨ Wbtw ℝ p₂ p₃ p₁ := by
by_cases hp₁p₂ : p₁ = p₂; · simp [hp₁p₂]
by_cases hp₃p₂ : p₃ = p₂; · simp [hp₃p₂]
rw [oangle_eq_zero_iff_angle_eq_zero hp₁p₂ hp₃p₂, angle_eq_zero_iff_ne_and_wbtw]
simp [hp₁p₂, hp₃p₂]
#align euclidean_geometry.oangle_eq_zero_iff_wbtw EuclideanGeometry.oangle_eq_zero_iff_wbtw
theorem _root_.Wbtw.oangle_eq_left {p₁ p₁' p₂ p₃ : P} (h : Wbtw ℝ p₂ p₁ p₁') (hp₁p₂ : p₁ ≠ p₂) :
∡ p₁ p₂ p₃ = ∡ p₁' p₂ p₃ := by
by_cases hp₃p₂ : p₃ = p₂; · simp [hp₃p₂]
by_cases hp₁'p₂ : p₁' = p₂; · rw [hp₁'p₂, wbtw_self_iff] at h; exact False.elim (hp₁p₂ h)
rw [← oangle_add hp₁'p₂ hp₁p₂ hp₃p₂, h.oangle₃₁₂_eq_zero, zero_add]
#align wbtw.oangle_eq_left Wbtw.oangle_eq_left
theorem _root_.Sbtw.oangle_eq_left {p₁ p₁' p₂ p₃ : P} (h : Sbtw ℝ p₂ p₁ p₁') :
∡ p₁ p₂ p₃ = ∡ p₁' p₂ p₃ :=
h.wbtw.oangle_eq_left h.ne_left
#align sbtw.oangle_eq_left Sbtw.oangle_eq_left
| Mathlib/Geometry/Euclidean/Angle/Oriented/Affine.lean | 571 | 572 | theorem _root_.Wbtw.oangle_eq_right {p₁ p₂ p₃ p₃' : P} (h : Wbtw ℝ p₂ p₃ p₃') (hp₃p₂ : p₃ ≠ p₂) :
∡ p₁ p₂ p₃ = ∡ p₁ p₂ p₃' := by | rw [oangle_rev, h.oangle_eq_left hp₃p₂, ← oangle_rev]
|
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 squareCylinders
def squareCylinders (C : ∀ i, Set (Set (α i))) : Set (Set (∀ i, α i)) :=
{S | ∃ s : Finset ι, ∃ t ∈ univ.pi C, S = (s : Set ι).pi t}
theorem squareCylinders_eq_iUnion_image (C : ∀ i, Set (Set (α i))) :
squareCylinders C = ⋃ s : Finset ι, (fun t ↦ (s : Set ι).pi t) '' univ.pi C := by
ext1 f
simp only [squareCylinders, mem_iUnion, mem_image, mem_univ_pi, exists_prop, mem_setOf_eq,
eq_comm (a := f)]
| Mathlib/MeasureTheory/Constructions/Cylinders.lean | 63 | 105 | theorem isPiSystem_squareCylinders {C : ∀ i, Set (Set (α i))} (hC : ∀ i, IsPiSystem (C i))
(hC_univ : ∀ i, univ ∈ C i) :
IsPiSystem (squareCylinders C) := by |
rintro S₁ ⟨s₁, t₁, h₁, rfl⟩ S₂ ⟨s₂, t₂, h₂, rfl⟩ hst_nonempty
classical
let t₁' := s₁.piecewise t₁ (fun i ↦ univ)
let t₂' := s₂.piecewise t₂ (fun i ↦ univ)
have h1 : ∀ i ∈ (s₁ : Set ι), t₁ i = t₁' i :=
fun i hi ↦ (Finset.piecewise_eq_of_mem _ _ _ hi).symm
have h1' : ∀ i ∉ (s₁ : Set ι), t₁' i = univ :=
fun i hi ↦ Finset.piecewise_eq_of_not_mem _ _ _ hi
have h2 : ∀ i ∈ (s₂ : Set ι), t₂ i = t₂' i :=
fun i hi ↦ (Finset.piecewise_eq_of_mem _ _ _ hi).symm
have h2' : ∀ i ∉ (s₂ : Set ι), t₂' i = univ :=
fun i hi ↦ Finset.piecewise_eq_of_not_mem _ _ _ hi
rw [Set.pi_congr rfl h1, Set.pi_congr rfl h2, ← union_pi_inter h1' h2']
refine ⟨s₁ ∪ s₂, fun i ↦ t₁' i ∩ t₂' i, ?_, ?_⟩
· rw [mem_univ_pi]
intro i
have : (t₁' i ∩ t₂' i).Nonempty := by
obtain ⟨f, hf⟩ := hst_nonempty
rw [Set.pi_congr rfl h1, Set.pi_congr rfl h2, mem_inter_iff, mem_pi, mem_pi] at hf
refine ⟨f i, ⟨?_, ?_⟩⟩
· by_cases hi₁ : i ∈ s₁
· exact hf.1 i hi₁
· rw [h1' i hi₁]
exact mem_univ _
· by_cases hi₂ : i ∈ s₂
· exact hf.2 i hi₂
· rw [h2' i hi₂]
exact mem_univ _
refine hC i _ ?_ _ ?_ this
· by_cases hi₁ : i ∈ s₁
· rw [← h1 i hi₁]
exact h₁ i (mem_univ _)
· rw [h1' i hi₁]
exact hC_univ i
· by_cases hi₂ : i ∈ s₂
· rw [← h2 i hi₂]
exact h₂ i (mem_univ _)
· rw [h2' i hi₂]
exact hC_univ i
· rw [Finset.coe_union]
|
import Mathlib.Analysis.BoxIntegral.Partition.Filter
import Mathlib.Analysis.BoxIntegral.Partition.Measure
import Mathlib.Topology.UniformSpace.Compact
import Mathlib.Init.Data.Bool.Lemmas
#align_import analysis.box_integral.basic from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982"
open scoped Classical Topology NNReal Filter Uniformity BoxIntegral
open Set Finset Function Filter Metric BoxIntegral.IntegrationParams
noncomputable section
namespace BoxIntegral
universe u v w
variable {ι : Type u} {E : Type v} {F : Type w} [NormedAddCommGroup E] [NormedSpace ℝ E]
[NormedAddCommGroup F] [NormedSpace ℝ F] {I J : Box ι} {π : TaggedPrepartition I}
open TaggedPrepartition
local notation "ℝⁿ" => ι → ℝ
def integralSum (f : ℝⁿ → E) (vol : ι →ᵇᵃ E →L[ℝ] F) (π : TaggedPrepartition I) : F :=
∑ J ∈ π.boxes, vol J (f (π.tag J))
#align box_integral.integral_sum BoxIntegral.integralSum
theorem integralSum_biUnionTagged (f : ℝⁿ → E) (vol : ι →ᵇᵃ E →L[ℝ] F) (π : Prepartition I)
(πi : ∀ J, TaggedPrepartition J) :
integralSum f vol (π.biUnionTagged πi) = ∑ J ∈ π.boxes, integralSum f vol (πi J) := by
refine (π.sum_biUnion_boxes _ _).trans <| sum_congr rfl fun J hJ => sum_congr rfl fun J' hJ' => ?_
rw [π.tag_biUnionTagged hJ hJ']
#align box_integral.integral_sum_bUnion_tagged BoxIntegral.integralSum_biUnionTagged
theorem integralSum_biUnion_partition (f : ℝⁿ → E) (vol : ι →ᵇᵃ E →L[ℝ] F)
(π : TaggedPrepartition I) (πi : ∀ J, Prepartition J) (hπi : ∀ J ∈ π, (πi J).IsPartition) :
integralSum f vol (π.biUnionPrepartition πi) = integralSum f vol π := by
refine (π.sum_biUnion_boxes _ _).trans (sum_congr rfl fun J hJ => ?_)
calc
(∑ J' ∈ (πi J).boxes, vol J' (f (π.tag <| π.toPrepartition.biUnionIndex πi J'))) =
∑ J' ∈ (πi J).boxes, vol J' (f (π.tag J)) :=
sum_congr rfl fun J' hJ' => by rw [Prepartition.biUnionIndex_of_mem _ hJ hJ']
_ = vol J (f (π.tag J)) :=
(vol.map ⟨⟨fun g : E →L[ℝ] F => g (f (π.tag J)), rfl⟩, fun _ _ => rfl⟩).sum_partition_boxes
le_top (hπi J hJ)
#align box_integral.integral_sum_bUnion_partition BoxIntegral.integralSum_biUnion_partition
theorem integralSum_inf_partition (f : ℝⁿ → E) (vol : ι →ᵇᵃ E →L[ℝ] F) (π : TaggedPrepartition I)
{π' : Prepartition I} (h : π'.IsPartition) :
integralSum f vol (π.infPrepartition π') = integralSum f vol π :=
integralSum_biUnion_partition f vol π _ fun _J hJ => h.restrict (Prepartition.le_of_mem _ hJ)
#align box_integral.integral_sum_inf_partition BoxIntegral.integralSum_inf_partition
theorem integralSum_fiberwise {α} (g : Box ι → α) (f : ℝⁿ → E) (vol : ι →ᵇᵃ E →L[ℝ] F)
(π : TaggedPrepartition I) :
(∑ y ∈ π.boxes.image g, integralSum f vol (π.filter (g · = y))) = integralSum f vol π :=
π.sum_fiberwise g fun J => vol J (f <| π.tag J)
#align box_integral.integral_sum_fiberwise BoxIntegral.integralSum_fiberwise
theorem integralSum_sub_partitions (f : ℝⁿ → E) (vol : ι →ᵇᵃ E →L[ℝ] F)
{π₁ π₂ : TaggedPrepartition I} (h₁ : π₁.IsPartition) (h₂ : π₂.IsPartition) :
integralSum f vol π₁ - integralSum f vol π₂ =
∑ J ∈ (π₁.toPrepartition ⊓ π₂.toPrepartition).boxes,
(vol J (f <| (π₁.infPrepartition π₂.toPrepartition).tag J) -
vol J (f <| (π₂.infPrepartition π₁.toPrepartition).tag J)) := by
rw [← integralSum_inf_partition f vol π₁ h₂, ← integralSum_inf_partition f vol π₂ h₁,
integralSum, integralSum, Finset.sum_sub_distrib]
simp only [infPrepartition_toPrepartition, inf_comm]
#align box_integral.integral_sum_sub_partitions BoxIntegral.integralSum_sub_partitions
@[simp]
theorem integralSum_disjUnion (f : ℝⁿ → E) (vol : ι →ᵇᵃ E →L[ℝ] F) {π₁ π₂ : TaggedPrepartition I}
(h : Disjoint π₁.iUnion π₂.iUnion) :
integralSum f vol (π₁.disjUnion π₂ h) = integralSum f vol π₁ + integralSum f vol π₂ := by
refine (Prepartition.sum_disj_union_boxes h _).trans
(congr_arg₂ (· + ·) (sum_congr rfl fun J hJ => ?_) (sum_congr rfl fun J hJ => ?_))
· rw [disjUnion_tag_of_mem_left _ hJ]
· rw [disjUnion_tag_of_mem_right _ hJ]
#align box_integral.integral_sum_disj_union BoxIntegral.integralSum_disjUnion
@[simp]
theorem integralSum_add (f g : ℝⁿ → E) (vol : ι →ᵇᵃ E →L[ℝ] F) (π : TaggedPrepartition I) :
integralSum (f + g) vol π = integralSum f vol π + integralSum g vol π := by
simp only [integralSum, Pi.add_apply, (vol _).map_add, Finset.sum_add_distrib]
#align box_integral.integral_sum_add BoxIntegral.integralSum_add
@[simp]
theorem integralSum_neg (f : ℝⁿ → E) (vol : ι →ᵇᵃ E →L[ℝ] F) (π : TaggedPrepartition I) :
integralSum (-f) vol π = -integralSum f vol π := by
simp only [integralSum, Pi.neg_apply, (vol _).map_neg, Finset.sum_neg_distrib]
#align box_integral.integral_sum_neg BoxIntegral.integralSum_neg
@[simp]
theorem integralSum_smul (c : ℝ) (f : ℝⁿ → E) (vol : ι →ᵇᵃ E →L[ℝ] F) (π : TaggedPrepartition I) :
integralSum (c • f) vol π = c • integralSum f vol π := by
simp only [integralSum, Finset.smul_sum, Pi.smul_apply, ContinuousLinearMap.map_smul]
#align box_integral.integral_sum_smul BoxIntegral.integralSum_smul
variable [Fintype ι]
def HasIntegral (I : Box ι) (l : IntegrationParams) (f : ℝⁿ → E) (vol : ι →ᵇᵃ E →L[ℝ] F) (y : F) :
Prop :=
Tendsto (integralSum f vol) (l.toFilteriUnion I ⊤) (𝓝 y)
#align box_integral.has_integral BoxIntegral.HasIntegral
def Integrable (I : Box ι) (l : IntegrationParams) (f : ℝⁿ → E) (vol : ι →ᵇᵃ E →L[ℝ] F) :=
∃ y, HasIntegral I l f vol y
#align box_integral.integrable BoxIntegral.Integrable
def integral (I : Box ι) (l : IntegrationParams) (f : ℝⁿ → E) (vol : ι →ᵇᵃ E →L[ℝ] F) :=
if h : Integrable I l f vol then h.choose else 0
#align box_integral.integral BoxIntegral.integral
-- Porting note: using the above notation ℝⁿ here causes the theorem below to be silently ignored
-- see https://leanprover.zulipchat.com/#narrow/stream/287929-mathlib4/topic/Lean.204.20doesn't.20add.20lemma.20to.20the.20environment/near/363764522
-- and https://github.com/leanprover/lean4/issues/2257
variable {l : IntegrationParams} {f g : (ι → ℝ) → E} {vol : ι →ᵇᵃ E →L[ℝ] F} {y y' : F}
theorem HasIntegral.tendsto (h : HasIntegral I l f vol y) :
Tendsto (integralSum f vol) (l.toFilteriUnion I ⊤) (𝓝 y) :=
h
#align box_integral.has_integral.tendsto BoxIntegral.HasIntegral.tendsto
theorem hasIntegral_iff : HasIntegral I l f vol y ↔
∀ ε > (0 : ℝ), ∃ r : ℝ≥0 → ℝⁿ → Ioi (0 : ℝ), (∀ c, l.RCond (r c)) ∧
∀ c π, l.MemBaseSet I c (r c) π → IsPartition π → dist (integralSum f vol π) y ≤ ε :=
((l.hasBasis_toFilteriUnion_top I).tendsto_iff nhds_basis_closedBall).trans <| by
simp [@forall_swap ℝ≥0 (TaggedPrepartition I)]
#align box_integral.has_integral_iff BoxIntegral.hasIntegral_iff
theorem HasIntegral.of_mul (a : ℝ)
(h : ∀ ε : ℝ, 0 < ε → ∃ r : ℝ≥0 → ℝⁿ → Ioi (0 : ℝ), (∀ c, l.RCond (r c)) ∧ ∀ c π,
l.MemBaseSet I c (r c) π → IsPartition π → dist (integralSum f vol π) y ≤ a * ε) :
HasIntegral I l f vol y := by
refine hasIntegral_iff.2 fun ε hε => ?_
rcases exists_pos_mul_lt hε a with ⟨ε', hε', ha⟩
rcases h ε' hε' with ⟨r, hr, H⟩
exact ⟨r, hr, fun c π hπ hπp => (H c π hπ hπp).trans ha.le⟩
#align box_integral.has_integral_of_mul BoxIntegral.HasIntegral.of_mul
theorem integrable_iff_cauchy [CompleteSpace F] :
Integrable I l f vol ↔ Cauchy ((l.toFilteriUnion I ⊤).map (integralSum f vol)) :=
cauchy_map_iff_exists_tendsto.symm
#align box_integral.integrable_iff_cauchy BoxIntegral.integrable_iff_cauchy
theorem integrable_iff_cauchy_basis [CompleteSpace F] : Integrable I l f vol ↔
∀ ε > (0 : ℝ), ∃ r : ℝ≥0 → ℝⁿ → Ioi (0 : ℝ), (∀ c, l.RCond (r c)) ∧
∀ c₁ c₂ π₁ π₂, l.MemBaseSet I c₁ (r c₁) π₁ → π₁.IsPartition → l.MemBaseSet I c₂ (r c₂) π₂ →
π₂.IsPartition → dist (integralSum f vol π₁) (integralSum f vol π₂) ≤ ε := by
rw [integrable_iff_cauchy, cauchy_map_iff',
(l.hasBasis_toFilteriUnion_top _).prod_self.tendsto_iff uniformity_basis_dist_le]
refine forall₂_congr fun ε _ => exists_congr fun r => ?_
simp only [exists_prop, Prod.forall, Set.mem_iUnion, exists_imp, prod_mk_mem_set_prod_eq, and_imp,
mem_inter_iff, mem_setOf_eq]
exact
and_congr Iff.rfl
⟨fun H c₁ c₂ π₁ π₂ h₁ hU₁ h₂ hU₂ => H π₁ π₂ c₁ h₁ hU₁ c₂ h₂ hU₂,
fun H π₁ π₂ c₁ h₁ hU₁ c₂ h₂ hU₂ => H c₁ c₂ π₁ π₂ h₁ hU₁ h₂ hU₂⟩
#align box_integral.integrable_iff_cauchy_basis BoxIntegral.integrable_iff_cauchy_basis
theorem HasIntegral.mono {l₁ l₂ : IntegrationParams} (h : HasIntegral I l₁ f vol y) (hl : l₂ ≤ l₁) :
HasIntegral I l₂ f vol y :=
h.mono_left <| IntegrationParams.toFilteriUnion_mono _ hl _
#align box_integral.has_integral.mono BoxIntegral.HasIntegral.mono
protected theorem Integrable.hasIntegral (h : Integrable I l f vol) :
HasIntegral I l f vol (integral I l f vol) := by
rw [integral, dif_pos h]
exact Classical.choose_spec h
#align box_integral.integrable.has_integral BoxIntegral.Integrable.hasIntegral
theorem Integrable.mono {l'} (h : Integrable I l f vol) (hle : l' ≤ l) : Integrable I l' f vol :=
⟨_, h.hasIntegral.mono hle⟩
#align box_integral.integrable.mono BoxIntegral.Integrable.mono
theorem HasIntegral.unique (h : HasIntegral I l f vol y) (h' : HasIntegral I l f vol y') : y = y' :=
tendsto_nhds_unique h h'
#align box_integral.has_integral.unique BoxIntegral.HasIntegral.unique
theorem HasIntegral.integrable (h : HasIntegral I l f vol y) : Integrable I l f vol :=
⟨_, h⟩
#align box_integral.has_integral.integrable BoxIntegral.HasIntegral.integrable
theorem HasIntegral.integral_eq (h : HasIntegral I l f vol y) : integral I l f vol = y :=
h.integrable.hasIntegral.unique h
#align box_integral.has_integral.integral_eq BoxIntegral.HasIntegral.integral_eq
nonrec theorem HasIntegral.add (h : HasIntegral I l f vol y) (h' : HasIntegral I l g vol y') :
HasIntegral I l (f + g) vol (y + y') := by
simpa only [HasIntegral, ← integralSum_add] using h.add h'
#align box_integral.has_integral.add BoxIntegral.HasIntegral.add
theorem Integrable.add (hf : Integrable I l f vol) (hg : Integrable I l g vol) :
Integrable I l (f + g) vol :=
(hf.hasIntegral.add hg.hasIntegral).integrable
#align box_integral.integrable.add BoxIntegral.Integrable.add
theorem integral_add (hf : Integrable I l f vol) (hg : Integrable I l g vol) :
integral I l (f + g) vol = integral I l f vol + integral I l g vol :=
(hf.hasIntegral.add hg.hasIntegral).integral_eq
#align box_integral.integral_add BoxIntegral.integral_add
nonrec theorem HasIntegral.neg (hf : HasIntegral I l f vol y) : HasIntegral I l (-f) vol (-y) := by
simpa only [HasIntegral, ← integralSum_neg] using hf.neg
#align box_integral.has_integral.neg BoxIntegral.HasIntegral.neg
theorem Integrable.neg (hf : Integrable I l f vol) : Integrable I l (-f) vol :=
hf.hasIntegral.neg.integrable
#align box_integral.integrable.neg BoxIntegral.Integrable.neg
theorem Integrable.of_neg (hf : Integrable I l (-f) vol) : Integrable I l f vol :=
neg_neg f ▸ hf.neg
#align box_integral.integrable.of_neg BoxIntegral.Integrable.of_neg
@[simp]
theorem integrable_neg : Integrable I l (-f) vol ↔ Integrable I l f vol :=
⟨fun h => h.of_neg, fun h => h.neg⟩
#align box_integral.integrable_neg BoxIntegral.integrable_neg
@[simp]
theorem integral_neg : integral I l (-f) vol = -integral I l f vol :=
if h : Integrable I l f vol then h.hasIntegral.neg.integral_eq
else by rw [integral, integral, dif_neg h, dif_neg (mt Integrable.of_neg h), neg_zero]
#align box_integral.integral_neg BoxIntegral.integral_neg
theorem HasIntegral.sub (h : HasIntegral I l f vol y) (h' : HasIntegral I l g vol y') :
HasIntegral I l (f - g) vol (y - y') := by simpa only [sub_eq_add_neg] using h.add h'.neg
#align box_integral.has_integral.sub BoxIntegral.HasIntegral.sub
theorem Integrable.sub (hf : Integrable I l f vol) (hg : Integrable I l g vol) :
Integrable I l (f - g) vol :=
(hf.hasIntegral.sub hg.hasIntegral).integrable
#align box_integral.integrable.sub BoxIntegral.Integrable.sub
theorem integral_sub (hf : Integrable I l f vol) (hg : Integrable I l g vol) :
integral I l (f - g) vol = integral I l f vol - integral I l g vol :=
(hf.hasIntegral.sub hg.hasIntegral).integral_eq
#align box_integral.integral_sub BoxIntegral.integral_sub
theorem hasIntegral_const (c : E) : HasIntegral I l (fun _ => c) vol (vol I c) :=
tendsto_const_nhds.congr' <| (l.eventually_isPartition I).mono fun _π hπ => Eq.symm <|
(vol.map ⟨⟨fun g : E →L[ℝ] F ↦ g c, rfl⟩, fun _ _ ↦ rfl⟩).sum_partition_boxes le_top hπ
#align box_integral.has_integral_const BoxIntegral.hasIntegral_const
@[simp]
theorem integral_const (c : E) : integral I l (fun _ => c) vol = vol I c :=
(hasIntegral_const c).integral_eq
#align box_integral.integral_const BoxIntegral.integral_const
theorem integrable_const (c : E) : Integrable I l (fun _ => c) vol :=
⟨_, hasIntegral_const c⟩
#align box_integral.integrable_const BoxIntegral.integrable_const
theorem hasIntegral_zero : HasIntegral I l (fun _ => (0 : E)) vol 0 := by
simpa only [← (vol I).map_zero] using hasIntegral_const (0 : E)
#align box_integral.has_integral_zero BoxIntegral.hasIntegral_zero
theorem integrable_zero : Integrable I l (fun _ => (0 : E)) vol :=
⟨0, hasIntegral_zero⟩
#align box_integral.integrable_zero BoxIntegral.integrable_zero
theorem integral_zero : integral I l (fun _ => (0 : E)) vol = 0 :=
hasIntegral_zero.integral_eq
#align box_integral.integral_zero BoxIntegral.integral_zero
theorem HasIntegral.sum {α : Type*} {s : Finset α} {f : α → ℝⁿ → E} {g : α → F}
(h : ∀ i ∈ s, HasIntegral I l (f i) vol (g i)) :
HasIntegral I l (fun x => ∑ i ∈ s, f i x) vol (∑ i ∈ s, g i) := by
induction' s using Finset.induction_on with a s ha ihs; · simp [hasIntegral_zero]
simp only [Finset.sum_insert ha]; rw [Finset.forall_mem_insert] at h
exact h.1.add (ihs h.2)
#align box_integral.has_integral_sum BoxIntegral.HasIntegral.sum
theorem HasIntegral.smul (hf : HasIntegral I l f vol y) (c : ℝ) :
HasIntegral I l (c • f) vol (c • y) := by
simpa only [HasIntegral, ← integralSum_smul] using
(tendsto_const_nhds : Tendsto _ _ (𝓝 c)).smul hf
#align box_integral.has_integral.smul BoxIntegral.HasIntegral.smul
theorem Integrable.smul (hf : Integrable I l f vol) (c : ℝ) : Integrable I l (c • f) vol :=
(hf.hasIntegral.smul c).integrable
#align box_integral.integrable.smul BoxIntegral.Integrable.smul
theorem Integrable.of_smul {c : ℝ} (hf : Integrable I l (c • f) vol) (hc : c ≠ 0) :
Integrable I l f vol := by
simpa [inv_smul_smul₀ hc] using hf.smul c⁻¹
#align box_integral.integrable.of_smul BoxIntegral.Integrable.of_smul
@[simp]
theorem integral_smul (c : ℝ) : integral I l (fun x => c • f x) vol = c • integral I l f vol := by
rcases eq_or_ne c 0 with (rfl | hc); · simp only [zero_smul, integral_zero]
by_cases hf : Integrable I l f vol
· exact (hf.hasIntegral.smul c).integral_eq
· have : ¬Integrable I l (fun x => c • f x) vol := mt (fun h => h.of_smul hc) hf
rw [integral, integral, dif_neg hf, dif_neg this, smul_zero]
#align box_integral.integral_smul BoxIntegral.integral_smul
open MeasureTheory
theorem integral_nonneg {g : ℝⁿ → ℝ} (hg : ∀ x ∈ Box.Icc I, 0 ≤ g x) (μ : Measure ℝⁿ)
[IsLocallyFiniteMeasure μ] : 0 ≤ integral I l g μ.toBoxAdditive.toSMul := by
by_cases hgi : Integrable I l g μ.toBoxAdditive.toSMul
· refine ge_of_tendsto' hgi.hasIntegral fun π => sum_nonneg fun J _ => ?_
exact mul_nonneg ENNReal.toReal_nonneg (hg _ <| π.tag_mem_Icc _)
· rw [integral, dif_neg hgi]
#align box_integral.integral_nonneg BoxIntegral.integral_nonneg
theorem norm_integral_le_of_norm_le {g : ℝⁿ → ℝ} (hle : ∀ x ∈ Box.Icc I, ‖f x‖ ≤ g x)
(μ : Measure ℝⁿ) [IsLocallyFiniteMeasure μ] (hg : Integrable I l g μ.toBoxAdditive.toSMul) :
‖(integral I l f μ.toBoxAdditive.toSMul : E)‖ ≤ integral I l g μ.toBoxAdditive.toSMul := by
by_cases hfi : Integrable.{u, v, v} I l f μ.toBoxAdditive.toSMul
· refine le_of_tendsto_of_tendsto' hfi.hasIntegral.norm hg.hasIntegral fun π => ?_
refine norm_sum_le_of_le _ fun J _ => ?_
simp only [BoxAdditiveMap.toSMul_apply, norm_smul, smul_eq_mul, Real.norm_eq_abs,
μ.toBoxAdditive_apply, abs_of_nonneg ENNReal.toReal_nonneg]
exact mul_le_mul_of_nonneg_left (hle _ <| π.tag_mem_Icc _) ENNReal.toReal_nonneg
· rw [integral, dif_neg hfi, norm_zero]
exact integral_nonneg (fun x hx => (norm_nonneg _).trans (hle x hx)) μ
#align box_integral.norm_integral_le_of_norm_le BoxIntegral.norm_integral_le_of_norm_le
theorem norm_integral_le_of_le_const {c : ℝ}
(hc : ∀ x ∈ Box.Icc I, ‖f x‖ ≤ c) (μ : Measure ℝⁿ) [IsLocallyFiniteMeasure μ] :
‖(integral I l f μ.toBoxAdditive.toSMul : E)‖ ≤ (μ I).toReal * c := by
simpa only [integral_const] using norm_integral_le_of_norm_le hc μ (integrable_const c)
#align box_integral.norm_integral_le_of_le_const BoxIntegral.norm_integral_le_of_le_const
open MeasureTheory
variable (l)
theorem integrable_of_continuousOn [CompleteSpace E] {I : Box ι} {f : ℝⁿ → E}
(hc : ContinuousOn f (Box.Icc I)) (μ : Measure ℝⁿ) [IsLocallyFiniteMeasure μ] :
Integrable.{u, v, v} I l f μ.toBoxAdditive.toSMul := by
have huc := I.isCompact_Icc.uniformContinuousOn_of_continuous hc
rw [Metric.uniformContinuousOn_iff_le] at huc
refine integrable_iff_cauchy_basis.2 fun ε ε0 => ?_
rcases exists_pos_mul_lt ε0 (μ.toBoxAdditive I) with ⟨ε', ε0', hε⟩
rcases huc ε' ε0' with ⟨δ, δ0 : 0 < δ, Hδ⟩
refine ⟨fun _ _ => ⟨δ / 2, half_pos δ0⟩, fun _ _ _ => rfl, fun c₁ c₂ π₁ π₂ h₁ h₁p h₂ h₂p => ?_⟩
simp only [dist_eq_norm, integralSum_sub_partitions _ _ h₁p h₂p, BoxAdditiveMap.toSMul_apply,
← smul_sub]
have : ∀ J ∈ π₁.toPrepartition ⊓ π₂.toPrepartition,
‖μ.toBoxAdditive J • (f ((π₁.infPrepartition π₂.toPrepartition).tag J) -
f ((π₂.infPrepartition π₁.toPrepartition).tag J))‖ ≤ μ.toBoxAdditive J * ε' := by
intro J hJ
have : 0 ≤ μ.toBoxAdditive J := ENNReal.toReal_nonneg
rw [norm_smul, Real.norm_eq_abs, abs_of_nonneg this, ← dist_eq_norm]
refine mul_le_mul_of_nonneg_left ?_ this
refine Hδ _ (TaggedPrepartition.tag_mem_Icc _ _) _ (TaggedPrepartition.tag_mem_Icc _ _) ?_
rw [← add_halves δ]
refine (dist_triangle_left _ _ J.upper).trans (add_le_add (h₁.1 _ ?_ ?_) (h₂.1 _ ?_ ?_))
· exact Prepartition.biUnionIndex_mem _ hJ
· exact Box.le_iff_Icc.1 (Prepartition.le_biUnionIndex _ hJ) J.upper_mem_Icc
· rw [_root_.inf_comm] at hJ
exact Prepartition.biUnionIndex_mem _ hJ
· rw [_root_.inf_comm] at hJ
exact Box.le_iff_Icc.1 (Prepartition.le_biUnionIndex _ hJ) J.upper_mem_Icc
refine (norm_sum_le_of_le _ this).trans ?_
rw [← Finset.sum_mul, μ.toBoxAdditive.sum_partition_boxes le_top (h₁p.inf h₂p)]
exact hε.le
#align box_integral.integrable_of_continuous_on BoxIntegral.integrable_of_continuousOn
variable {l}
| Mathlib/Analysis/BoxIntegral/Basic.lean | 718 | 789 | theorem HasIntegral.of_bRiemann_eq_false_of_forall_isLittleO (hl : l.bRiemann = false)
(B : ι →ᵇᵃ[I] ℝ) (hB0 : ∀ J, 0 ≤ B J) (g : ι →ᵇᵃ[I] F) (s : Set ℝⁿ) (hs : s.Countable)
(hlH : s.Nonempty → l.bHenstock = true)
(H₁ : ∀ (c : ℝ≥0), ∀ x ∈ Box.Icc I ∩ s, ∀ ε > (0 : ℝ),
∃ δ > 0, ∀ J ≤ I, Box.Icc J ⊆ Metric.closedBall x δ → x ∈ Box.Icc J →
(l.bDistortion → J.distortion ≤ c) → dist (vol J (f x)) (g J) ≤ ε)
(H₂ : ∀ (c : ℝ≥0), ∀ x ∈ Box.Icc I \ s, ∀ ε > (0 : ℝ),
∃ δ > 0, ∀ J ≤ I, Box.Icc J ⊆ Metric.closedBall x δ → (l.bHenstock → x ∈ Box.Icc J) →
(l.bDistortion → J.distortion ≤ c) → dist (vol J (f x)) (g J) ≤ ε * B J) :
HasIntegral I l f vol (g I) := by |
/- We choose `r x` differently for `x ∈ s` and `x ∉ s`.
For `x ∈ s`, we choose `εs` such that `∑' x : s, εs x < ε / 2 / 2 ^ #ι`, then choose `r x` so
that `dist (vol J (f x)) (g J) ≤ εs x` for `J` in the `r x`-neighborhood of `x`. This guarantees
that the sum of these distances over boxes `J` such that `π.tag J ∈ s` is less than `ε / 2`. We
need an additional multiplier `2 ^ #ι` because different boxes can have the same tag.
For `x ∉ s`, we choose `r x` so that `dist (vol (J (f x))) (g J) ≤ (ε / 2 / B I) * B J` for a
box `J` in the `δ`-neighborhood of `x`. -/
refine ((l.hasBasis_toFilteriUnion_top _).tendsto_iff Metric.nhds_basis_closedBall).2 ?_
intro ε ε0
simp only [← exists_prop, gt_iff_lt, Subtype.exists'] at H₁ H₂
choose! δ₁ Hδ₁ using H₁
choose! δ₂ Hδ₂ using H₂
have ε0' := half_pos ε0; have H0 : 0 < (2 : ℝ) ^ Fintype.card ι := pow_pos zero_lt_two _
rcases hs.exists_pos_forall_sum_le (div_pos ε0' H0) with ⟨εs, hεs0, hεs⟩
simp only [le_div_iff' H0, mul_sum] at hεs
rcases exists_pos_mul_lt ε0' (B I) with ⟨ε', ε'0, hεI⟩
set δ : ℝ≥0 → ℝⁿ → Ioi (0 : ℝ) := fun c x => if x ∈ s then δ₁ c x (εs x) else (δ₂ c) x ε'
refine ⟨δ, fun c => l.rCond_of_bRiemann_eq_false hl, ?_⟩
simp only [Set.mem_iUnion, mem_inter_iff, mem_setOf_eq]
rintro π ⟨c, hπδ, hπp⟩
-- Now we split the sum into two parts based on whether `π.tag J` belongs to `s` or not.
rw [← g.sum_partition_boxes le_rfl hπp, mem_closedBall, integralSum,
← sum_filter_add_sum_filter_not π.boxes fun J => π.tag J ∈ s,
← sum_filter_add_sum_filter_not π.boxes fun J => π.tag J ∈ s, ← add_halves ε]
refine dist_add_add_le_of_le ?_ ?_
· rcases s.eq_empty_or_nonempty with (rfl | hsne); · simp [ε0'.le]
/- For the boxes such that `π.tag J ∈ s`, we use the fact that at most `2 ^ #ι` boxes have the
same tag. -/
specialize hlH hsne
have : ∀ J ∈ π.boxes.filter fun J => π.tag J ∈ s,
dist (vol J (f <| π.tag J)) (g J) ≤ εs (π.tag J) := fun J hJ ↦ by
rw [Finset.mem_filter] at hJ; cases' hJ with hJ hJs
refine Hδ₁ c _ ⟨π.tag_mem_Icc _, hJs⟩ _ (hεs0 _) _ (π.le_of_mem' _ hJ) ?_
(hπδ.2 hlH J hJ) fun hD => (Finset.le_sup hJ).trans (hπδ.3 hD)
convert hπδ.1 J hJ using 3; exact (if_pos hJs).symm
refine (dist_sum_sum_le_of_le _ this).trans ?_
rw [sum_comp]
refine (sum_le_sum ?_).trans (hεs _ ?_)
· rintro b -
rw [← Nat.cast_two, ← Nat.cast_pow, ← nsmul_eq_mul]
refine nsmul_le_nsmul_left (hεs0 _).le ?_
refine (Finset.card_le_card ?_).trans ((hπδ.isHenstock hlH).card_filter_tag_eq_le b)
exact filter_subset_filter _ (filter_subset _ _)
· rw [Finset.coe_image, Set.image_subset_iff]
exact fun J hJ => (Finset.mem_filter.1 hJ).2
/- Now we deal with boxes such that `π.tag J ∉ s`.
In this case the estimate is straightforward. -/
-- Porting note: avoided strange elaboration issues by rewriting using `calc`
calc
dist (∑ J ∈ π.boxes.filter (¬tag π · ∈ s), vol J (f (tag π J)))
(∑ J ∈ π.boxes.filter (¬tag π · ∈ s), g J)
≤ ∑ J ∈ π.boxes.filter (¬tag π · ∈ s), ε' * B J := dist_sum_sum_le_of_le _ fun J hJ ↦ by
rw [Finset.mem_filter] at hJ; cases' hJ with hJ hJs
refine Hδ₂ c _ ⟨π.tag_mem_Icc _, hJs⟩ _ ε'0 _ (π.le_of_mem' _ hJ) ?_ (fun hH => hπδ.2 hH J hJ)
fun hD => (Finset.le_sup hJ).trans (hπδ.3 hD)
convert hπδ.1 J hJ using 3; exact (if_neg hJs).symm
_ ≤ ∑ J ∈ π.boxes, ε' * B J := sum_le_sum_of_subset_of_nonneg (filter_subset _ _) fun _ _ _ ↦
mul_nonneg ε'0.le (hB0 _)
_ = B I * ε' := by rw [← mul_sum, B.sum_partition_boxes le_rfl hπp, mul_comm]
_ ≤ ε / 2 := hεI.le
|
import Mathlib.Probability.Kernel.Disintegration.Unique
import Mathlib.Probability.Notation
#align_import probability.kernel.cond_distrib from "leanprover-community/mathlib"@"00abe0695d8767201e6d008afa22393978bb324d"
open MeasureTheory Set Filter TopologicalSpace
open scoped ENNReal MeasureTheory ProbabilityTheory
namespace ProbabilityTheory
variable {α β Ω F : Type*} [MeasurableSpace Ω] [StandardBorelSpace Ω]
[Nonempty Ω] [NormedAddCommGroup F] {mα : MeasurableSpace α} {μ : Measure α} [IsFiniteMeasure μ]
{X : α → β} {Y : α → Ω}
noncomputable irreducible_def condDistrib {_ : MeasurableSpace α} [MeasurableSpace β] (Y : α → Ω)
(X : α → β) (μ : Measure α) [IsFiniteMeasure μ] : kernel β Ω :=
(μ.map fun a => (X a, Y a)).condKernel
#align probability_theory.cond_distrib ProbabilityTheory.condDistrib
instance [MeasurableSpace β] : IsMarkovKernel (condDistrib Y X μ) := by
rw [condDistrib]; infer_instance
variable {mβ : MeasurableSpace β} {s : Set Ω} {t : Set β} {f : β × Ω → F}
lemma condDistrib_apply_of_ne_zero [MeasurableSingletonClass β]
(hY : Measurable Y) (x : β) (hX : μ.map X {x} ≠ 0) (s : Set Ω) :
condDistrib Y X μ x s = (μ.map X {x})⁻¹ * μ.map (fun a => (X a, Y a)) ({x} ×ˢ s) := by
rw [condDistrib, Measure.condKernel_apply_of_ne_zero _ s]
· rw [Measure.fst_map_prod_mk hY]
· rwa [Measure.fst_map_prod_mk hY]
| Mathlib/Probability/Kernel/CondDistrib.lean | 120 | 130 | theorem condDistrib_ae_eq_of_measure_eq_compProd (hX : Measurable X) (hY : Measurable Y)
(κ : kernel β Ω) [IsFiniteKernel κ] (hκ : μ.map (fun x => (X x, Y x)) = μ.map X ⊗ₘ κ) :
∀ᵐ x ∂μ.map X, κ x = condDistrib Y X μ x := by |
have heq : μ.map X = (μ.map (fun x ↦ (X x, Y x))).fst := by
ext s hs
rw [Measure.map_apply hX hs, Measure.fst_apply hs, Measure.map_apply]
exacts [rfl, Measurable.prod hX hY, measurable_fst hs]
rw [heq, condDistrib]
refine eq_condKernel_of_measure_eq_compProd _ ?_
convert hκ
exact heq.symm
|
import Mathlib.Geometry.Manifold.SmoothManifoldWithCorners
import Mathlib.Geometry.Manifold.LocalInvariantProperties
#align_import geometry.manifold.cont_mdiff from "leanprover-community/mathlib"@"e5ab837fc252451f3eb9124ae6e7b6f57455e7b9"
open Set Function Filter ChartedSpace SmoothManifoldWithCorners
open scoped Topology Manifold
variable {𝕜 : Type*} [NontriviallyNormedField 𝕜]
-- declare a smooth manifold `M` over the pair `(E, H)`.
{E : Type*}
[NormedAddCommGroup E] [NormedSpace 𝕜 E] {H : Type*} [TopologicalSpace H]
(I : ModelWithCorners 𝕜 E H) {M : Type*} [TopologicalSpace M] [ChartedSpace H M]
[SmoothManifoldWithCorners I M]
-- declare a smooth manifold `M'` over the pair `(E', H')`.
{E' : Type*}
[NormedAddCommGroup E'] [NormedSpace 𝕜 E'] {H' : Type*} [TopologicalSpace H']
(I' : ModelWithCorners 𝕜 E' H') {M' : Type*} [TopologicalSpace M'] [ChartedSpace H' M']
[SmoothManifoldWithCorners I' M']
-- declare a manifold `M''` over the pair `(E'', H'')`.
{E'' : Type*}
[NormedAddCommGroup E''] [NormedSpace 𝕜 E''] {H'' : Type*} [TopologicalSpace H'']
{I'' : ModelWithCorners 𝕜 E'' H''} {M'' : Type*} [TopologicalSpace M''] [ChartedSpace H'' M'']
-- declare a smooth manifold `N` over the pair `(F, G)`.
{F : Type*}
[NormedAddCommGroup F] [NormedSpace 𝕜 F] {G : Type*} [TopologicalSpace G]
{J : ModelWithCorners 𝕜 F G} {N : Type*} [TopologicalSpace N] [ChartedSpace G N]
[SmoothManifoldWithCorners J N]
-- declare a smooth manifold `N'` over the pair `(F', G')`.
{F' : Type*}
[NormedAddCommGroup F'] [NormedSpace 𝕜 F'] {G' : Type*} [TopologicalSpace G']
{J' : ModelWithCorners 𝕜 F' G'} {N' : Type*} [TopologicalSpace N'] [ChartedSpace G' N']
[SmoothManifoldWithCorners J' N']
-- F₁, F₂, F₃, F₄ are normed spaces
{F₁ : Type*}
[NormedAddCommGroup F₁] [NormedSpace 𝕜 F₁] {F₂ : Type*} [NormedAddCommGroup F₂]
[NormedSpace 𝕜 F₂] {F₃ : Type*} [NormedAddCommGroup F₃] [NormedSpace 𝕜 F₃] {F₄ : Type*}
[NormedAddCommGroup F₄] [NormedSpace 𝕜 F₄]
-- declare functions, sets, points and smoothness indices
{e : PartialHomeomorph M H}
{e' : PartialHomeomorph M' H'} {f f₁ : M → M'} {s s₁ t : Set M} {x : M} {m n : ℕ∞}
def ContDiffWithinAtProp (n : ℕ∞) (f : H → H') (s : Set H) (x : H) : Prop :=
ContDiffWithinAt 𝕜 n (I' ∘ f ∘ I.symm) (I.symm ⁻¹' s ∩ range I) (I x)
#align cont_diff_within_at_prop ContDiffWithinAtProp
theorem contDiffWithinAtProp_self_source {f : E → H'} {s : Set E} {x : E} :
ContDiffWithinAtProp 𝓘(𝕜, E) I' n f s x ↔ ContDiffWithinAt 𝕜 n (I' ∘ f) s x := by
simp_rw [ContDiffWithinAtProp, modelWithCornersSelf_coe, range_id, inter_univ,
modelWithCornersSelf_coe_symm, CompTriple.comp_eq, preimage_id_eq, id_eq]
#align cont_diff_within_at_prop_self_source contDiffWithinAtProp_self_source
theorem contDiffWithinAtProp_self {f : E → E'} {s : Set E} {x : E} :
ContDiffWithinAtProp 𝓘(𝕜, E) 𝓘(𝕜, E') n f s x ↔ ContDiffWithinAt 𝕜 n f s x :=
contDiffWithinAtProp_self_source 𝓘(𝕜, E')
#align cont_diff_within_at_prop_self contDiffWithinAtProp_self
theorem contDiffWithinAtProp_self_target {f : H → E'} {s : Set H} {x : H} :
ContDiffWithinAtProp I 𝓘(𝕜, E') n f s x ↔
ContDiffWithinAt 𝕜 n (f ∘ I.symm) (I.symm ⁻¹' s ∩ range I) (I x) :=
Iff.rfl
#align cont_diff_within_at_prop_self_target contDiffWithinAtProp_self_target
theorem contDiffWithinAt_localInvariantProp (n : ℕ∞) :
(contDiffGroupoid ∞ I).LocalInvariantProp (contDiffGroupoid ∞ I')
(ContDiffWithinAtProp I I' n) where
is_local {s x u f} u_open xu := by
have : I.symm ⁻¹' (s ∩ u) ∩ range I = I.symm ⁻¹' s ∩ range I ∩ I.symm ⁻¹' u := by
simp only [inter_right_comm, preimage_inter]
rw [ContDiffWithinAtProp, ContDiffWithinAtProp, this]
symm
apply contDiffWithinAt_inter
have : u ∈ 𝓝 (I.symm (I x)) := by
rw [ModelWithCorners.left_inv]
exact u_open.mem_nhds xu
apply ContinuousAt.preimage_mem_nhds I.continuous_symm.continuousAt this
right_invariance' {s x f e} he hx h := by
rw [ContDiffWithinAtProp] at h ⊢
have : I x = (I ∘ e.symm ∘ I.symm) (I (e x)) := by simp only [hx, mfld_simps]
rw [this] at h
have : I (e x) ∈ I.symm ⁻¹' e.target ∩ range I := by simp only [hx, mfld_simps]
have := (mem_groupoid_of_pregroupoid.2 he).2.contDiffWithinAt this
convert (h.comp' _ (this.of_le le_top)).mono_of_mem _ using 1
· ext y; simp only [mfld_simps]
refine mem_nhdsWithin.mpr
⟨I.symm ⁻¹' e.target, e.open_target.preimage I.continuous_symm, by
simp_rw [mem_preimage, I.left_inv, e.mapsTo hx], ?_⟩
mfld_set_tac
congr_of_forall {s x f g} h hx hf := by
apply hf.congr
· intro y hy
simp only [mfld_simps] at hy
simp only [h, hy, mfld_simps]
· simp only [hx, mfld_simps]
left_invariance' {s x f e'} he' hs hx h := by
rw [ContDiffWithinAtProp] at h ⊢
have A : (I' ∘ f ∘ I.symm) (I x) ∈ I'.symm ⁻¹' e'.source ∩ range I' := by
simp only [hx, mfld_simps]
have := (mem_groupoid_of_pregroupoid.2 he').1.contDiffWithinAt A
convert (this.of_le le_top).comp _ h _
· ext y; simp only [mfld_simps]
· intro y hy; simp only [mfld_simps] at hy; simpa only [hy, mfld_simps] using hs hy.1
#align cont_diff_within_at_local_invariant_prop contDiffWithinAt_localInvariantProp
theorem contDiffWithinAtProp_mono_of_mem (n : ℕ∞) ⦃s x t⦄ ⦃f : H → H'⦄ (hts : s ∈ 𝓝[t] x)
(h : ContDiffWithinAtProp I I' n f s x) : ContDiffWithinAtProp I I' n f t x := by
refine h.mono_of_mem ?_
refine inter_mem ?_ (mem_of_superset self_mem_nhdsWithin inter_subset_right)
rwa [← Filter.mem_map, ← I.image_eq, I.symm_map_nhdsWithin_image]
#align cont_diff_within_at_prop_mono_of_mem contDiffWithinAtProp_mono_of_mem
theorem contDiffWithinAtProp_id (x : H) : ContDiffWithinAtProp I I n id univ x := by
simp only [ContDiffWithinAtProp, id_comp, preimage_univ, univ_inter]
have : ContDiffWithinAt 𝕜 n id (range I) (I x) := contDiff_id.contDiffAt.contDiffWithinAt
refine this.congr (fun y hy => ?_) ?_
· simp only [ModelWithCorners.right_inv I hy, mfld_simps]
· simp only [mfld_simps]
#align cont_diff_within_at_prop_id contDiffWithinAtProp_id
def ContMDiffWithinAt (n : ℕ∞) (f : M → M') (s : Set M) (x : M) :=
LiftPropWithinAt (ContDiffWithinAtProp I I' n) f s x
#align cont_mdiff_within_at ContMDiffWithinAt
abbrev SmoothWithinAt (f : M → M') (s : Set M) (x : M) :=
ContMDiffWithinAt I I' ⊤ f s x
#align smooth_within_at SmoothWithinAt
def ContMDiffAt (n : ℕ∞) (f : M → M') (x : M) :=
ContMDiffWithinAt I I' n f univ x
#align cont_mdiff_at ContMDiffAt
theorem contMDiffAt_iff {n : ℕ∞} {f : M → M'} {x : M} :
ContMDiffAt I I' n f x ↔
ContinuousAt f x ∧
ContDiffWithinAt 𝕜 n (extChartAt I' (f x) ∘ f ∘ (extChartAt I x).symm) (range I)
(extChartAt I x x) :=
liftPropAt_iff.trans <| by rw [ContDiffWithinAtProp, preimage_univ, univ_inter]; rfl
#align cont_mdiff_at_iff contMDiffAt_iff
abbrev SmoothAt (f : M → M') (x : M) :=
ContMDiffAt I I' ⊤ f x
#align smooth_at SmoothAt
def ContMDiffOn (n : ℕ∞) (f : M → M') (s : Set M) :=
∀ x ∈ s, ContMDiffWithinAt I I' n f s x
#align cont_mdiff_on ContMDiffOn
abbrev SmoothOn (f : M → M') (s : Set M) :=
ContMDiffOn I I' ⊤ f s
#align smooth_on SmoothOn
def ContMDiff (n : ℕ∞) (f : M → M') :=
∀ x, ContMDiffAt I I' n f x
#align cont_mdiff ContMDiff
abbrev Smooth (f : M → M') :=
ContMDiff I I' ⊤ f
#align smooth Smooth
variable {I I'}
theorem ContMDiffWithinAt.of_le (hf : ContMDiffWithinAt I I' n f s x) (le : m ≤ n) :
ContMDiffWithinAt I I' m f s x := by
simp only [ContMDiffWithinAt, LiftPropWithinAt] at hf ⊢
exact ⟨hf.1, hf.2.of_le le⟩
#align cont_mdiff_within_at.of_le ContMDiffWithinAt.of_le
theorem ContMDiffAt.of_le (hf : ContMDiffAt I I' n f x) (le : m ≤ n) : ContMDiffAt I I' m f x :=
ContMDiffWithinAt.of_le hf le
#align cont_mdiff_at.of_le ContMDiffAt.of_le
theorem ContMDiffOn.of_le (hf : ContMDiffOn I I' n f s) (le : m ≤ n) : ContMDiffOn I I' m f s :=
fun x hx => (hf x hx).of_le le
#align cont_mdiff_on.of_le ContMDiffOn.of_le
theorem ContMDiff.of_le (hf : ContMDiff I I' n f) (le : m ≤ n) : ContMDiff I I' m f := fun x =>
(hf x).of_le le
#align cont_mdiff.of_le ContMDiff.of_le
theorem ContMDiff.smooth (h : ContMDiff I I' ⊤ f) : Smooth I I' f :=
h
#align cont_mdiff.smooth ContMDiff.smooth
theorem Smooth.contMDiff (h : Smooth I I' f) : ContMDiff I I' n f :=
h.of_le le_top
#align smooth.cont_mdiff Smooth.contMDiff
theorem ContMDiffOn.smoothOn (h : ContMDiffOn I I' ⊤ f s) : SmoothOn I I' f s :=
h
#align cont_mdiff_on.smooth_on ContMDiffOn.smoothOn
theorem SmoothOn.contMDiffOn (h : SmoothOn I I' f s) : ContMDiffOn I I' n f s :=
h.of_le le_top
#align smooth_on.cont_mdiff_on SmoothOn.contMDiffOn
theorem ContMDiffAt.smoothAt (h : ContMDiffAt I I' ⊤ f x) : SmoothAt I I' f x :=
h
#align cont_mdiff_at.smooth_at ContMDiffAt.smoothAt
theorem SmoothAt.contMDiffAt (h : SmoothAt I I' f x) : ContMDiffAt I I' n f x :=
h.of_le le_top
#align smooth_at.cont_mdiff_at SmoothAt.contMDiffAt
theorem ContMDiffWithinAt.smoothWithinAt (h : ContMDiffWithinAt I I' ⊤ f s x) :
SmoothWithinAt I I' f s x :=
h
#align cont_mdiff_within_at.smooth_within_at ContMDiffWithinAt.smoothWithinAt
theorem SmoothWithinAt.contMDiffWithinAt (h : SmoothWithinAt I I' f s x) :
ContMDiffWithinAt I I' n f s x :=
h.of_le le_top
#align smooth_within_at.cont_mdiff_within_at SmoothWithinAt.contMDiffWithinAt
theorem ContMDiff.contMDiffAt (h : ContMDiff I I' n f) : ContMDiffAt I I' n f x :=
h x
#align cont_mdiff.cont_mdiff_at ContMDiff.contMDiffAt
theorem Smooth.smoothAt (h : Smooth I I' f) : SmoothAt I I' f x :=
ContMDiff.contMDiffAt h
#align smooth.smooth_at Smooth.smoothAt
theorem contMDiffWithinAt_univ : ContMDiffWithinAt I I' n f univ x ↔ ContMDiffAt I I' n f x :=
Iff.rfl
#align cont_mdiff_within_at_univ contMDiffWithinAt_univ
theorem smoothWithinAt_univ : SmoothWithinAt I I' f univ x ↔ SmoothAt I I' f x :=
contMDiffWithinAt_univ
#align smooth_within_at_univ smoothWithinAt_univ
theorem contMDiffOn_univ : ContMDiffOn I I' n f univ ↔ ContMDiff I I' n f := by
simp only [ContMDiffOn, ContMDiff, contMDiffWithinAt_univ, forall_prop_of_true, mem_univ]
#align cont_mdiff_on_univ contMDiffOn_univ
theorem smoothOn_univ : SmoothOn I I' f univ ↔ Smooth I I' f :=
contMDiffOn_univ
#align smooth_on_univ smoothOn_univ
| Mathlib/Geometry/Manifold/ContMDiff/Defs.lean | 319 | 324 | theorem contMDiffWithinAt_iff :
ContMDiffWithinAt I I' n f s x ↔
ContinuousWithinAt f s x ∧
ContDiffWithinAt 𝕜 n (extChartAt I' (f x) ∘ f ∘ (extChartAt I x).symm)
((extChartAt I x).symm ⁻¹' s ∩ range I) (extChartAt I x x) := by |
simp_rw [ContMDiffWithinAt, liftPropWithinAt_iff']; rfl
|
import Mathlib.Analysis.NormedSpace.Star.Basic
import Mathlib.Analysis.NormedSpace.Spectrum
import Mathlib.Analysis.SpecialFunctions.Exponential
import Mathlib.Algebra.Star.StarAlgHom
#align_import analysis.normed_space.star.spectrum from "leanprover-community/mathlib"@"f0c8bf9245297a541f468be517f1bde6195105e9"
local postfix:max "⋆" => star
section
open scoped Topology ENNReal
open Filter ENNReal spectrum CstarRing NormedSpace
section ComplexScalars
open Complex
variable {A : Type*} [NormedRing A] [NormedAlgebra ℂ A] [CompleteSpace A] [StarRing A]
[CstarRing A]
local notation "↑ₐ" => algebraMap ℂ A
| Mathlib/Analysis/NormedSpace/Star/Spectrum.lean | 60 | 69 | theorem IsSelfAdjoint.spectralRadius_eq_nnnorm {a : A} (ha : IsSelfAdjoint a) :
spectralRadius ℂ a = ‖a‖₊ := by |
have hconst : Tendsto (fun _n : ℕ => (‖a‖₊ : ℝ≥0∞)) atTop _ := tendsto_const_nhds
refine tendsto_nhds_unique ?_ hconst
convert
(spectrum.pow_nnnorm_pow_one_div_tendsto_nhds_spectralRadius (a : A)).comp
(Nat.tendsto_pow_atTop_atTop_of_one_lt one_lt_two) using 1
refine funext fun n => ?_
rw [Function.comp_apply, ha.nnnorm_pow_two_pow, ENNReal.coe_pow, ← rpow_natCast, ← rpow_mul]
simp
|
import Mathlib.MeasureTheory.Measure.NullMeasurable
import Mathlib.MeasureTheory.MeasurableSpace.Basic
import Mathlib.Topology.Algebra.Order.LiminfLimsup
#align_import measure_theory.measure.measure_space from "leanprover-community/mathlib"@"343e80208d29d2d15f8050b929aa50fe4ce71b55"
noncomputable section
open Set
open Filter hiding map
open Function MeasurableSpace
open scoped Classical symmDiff
open Topology Filter ENNReal NNReal Interval MeasureTheory
variable {α β γ δ ι R R' : Type*}
namespace MeasureTheory
section
variable {m : MeasurableSpace α} {μ μ₁ μ₂ : Measure α} {s s₁ s₂ t : Set α}
instance ae_isMeasurablyGenerated : IsMeasurablyGenerated (ae μ) :=
⟨fun _s hs =>
let ⟨t, hst, htm, htμ⟩ := exists_measurable_superset_of_null hs
⟨tᶜ, compl_mem_ae_iff.2 htμ, htm.compl, compl_subset_comm.1 hst⟩⟩
#align measure_theory.ae_is_measurably_generated MeasureTheory.ae_isMeasurablyGenerated
theorem ae_uIoc_iff [LinearOrder α] {a b : α} {P : α → Prop} :
(∀ᵐ x ∂μ, x ∈ Ι a b → P x) ↔ (∀ᵐ x ∂μ, x ∈ Ioc a b → P x) ∧ ∀ᵐ x ∂μ, x ∈ Ioc b a → P x := by
simp only [uIoc_eq_union, mem_union, or_imp, eventually_and]
#align measure_theory.ae_uIoc_iff MeasureTheory.ae_uIoc_iff
theorem measure_union (hd : Disjoint s₁ s₂) (h : MeasurableSet s₂) : μ (s₁ ∪ s₂) = μ s₁ + μ s₂ :=
measure_union₀ h.nullMeasurableSet hd.aedisjoint
#align measure_theory.measure_union MeasureTheory.measure_union
theorem measure_union' (hd : Disjoint s₁ s₂) (h : MeasurableSet s₁) : μ (s₁ ∪ s₂) = μ s₁ + μ s₂ :=
measure_union₀' h.nullMeasurableSet hd.aedisjoint
#align measure_theory.measure_union' MeasureTheory.measure_union'
theorem measure_inter_add_diff (s : Set α) (ht : MeasurableSet t) : μ (s ∩ t) + μ (s \ t) = μ s :=
measure_inter_add_diff₀ _ ht.nullMeasurableSet
#align measure_theory.measure_inter_add_diff MeasureTheory.measure_inter_add_diff
theorem measure_diff_add_inter (s : Set α) (ht : MeasurableSet t) : μ (s \ t) + μ (s ∩ t) = μ s :=
(add_comm _ _).trans (measure_inter_add_diff s ht)
#align measure_theory.measure_diff_add_inter MeasureTheory.measure_diff_add_inter
theorem measure_union_add_inter (s : Set α) (ht : MeasurableSet t) :
μ (s ∪ t) + μ (s ∩ t) = μ s + μ t := by
rw [← measure_inter_add_diff (s ∪ t) ht, Set.union_inter_cancel_right, union_diff_right, ←
measure_inter_add_diff s ht]
ac_rfl
#align measure_theory.measure_union_add_inter MeasureTheory.measure_union_add_inter
theorem measure_union_add_inter' (hs : MeasurableSet s) (t : Set α) :
μ (s ∪ t) + μ (s ∩ t) = μ s + μ t := by
rw [union_comm, inter_comm, measure_union_add_inter t hs, add_comm]
#align measure_theory.measure_union_add_inter' MeasureTheory.measure_union_add_inter'
lemma measure_symmDiff_eq (hs : MeasurableSet s) (ht : MeasurableSet t) :
μ (s ∆ t) = μ (s \ t) + μ (t \ s) := by
simpa only [symmDiff_def, sup_eq_union] using measure_union disjoint_sdiff_sdiff (ht.diff hs)
lemma measure_symmDiff_le (s t u : Set α) :
μ (s ∆ u) ≤ μ (s ∆ t) + μ (t ∆ u) :=
le_trans (μ.mono <| symmDiff_triangle s t u) (measure_union_le (s ∆ t) (t ∆ u))
theorem measure_add_measure_compl (h : MeasurableSet s) : μ s + μ sᶜ = μ univ :=
measure_add_measure_compl₀ h.nullMeasurableSet
#align measure_theory.measure_add_measure_compl MeasureTheory.measure_add_measure_compl
theorem measure_biUnion₀ {s : Set β} {f : β → Set α} (hs : s.Countable)
(hd : s.Pairwise (AEDisjoint μ on f)) (h : ∀ b ∈ s, NullMeasurableSet (f b) μ) :
μ (⋃ b ∈ s, f b) = ∑' p : s, μ (f p) := by
haveI := hs.toEncodable
rw [biUnion_eq_iUnion]
exact measure_iUnion₀ (hd.on_injective Subtype.coe_injective fun x => x.2) fun x => h x x.2
#align measure_theory.measure_bUnion₀ MeasureTheory.measure_biUnion₀
theorem measure_biUnion {s : Set β} {f : β → Set α} (hs : s.Countable) (hd : s.PairwiseDisjoint f)
(h : ∀ b ∈ s, MeasurableSet (f b)) : μ (⋃ b ∈ s, f b) = ∑' p : s, μ (f p) :=
measure_biUnion₀ hs hd.aedisjoint fun b hb => (h b hb).nullMeasurableSet
#align measure_theory.measure_bUnion MeasureTheory.measure_biUnion
theorem measure_sUnion₀ {S : Set (Set α)} (hs : S.Countable) (hd : S.Pairwise (AEDisjoint μ))
(h : ∀ s ∈ S, NullMeasurableSet s μ) : μ (⋃₀ S) = ∑' s : S, μ s := by
rw [sUnion_eq_biUnion, measure_biUnion₀ hs hd h]
#align measure_theory.measure_sUnion₀ MeasureTheory.measure_sUnion₀
theorem measure_sUnion {S : Set (Set α)} (hs : S.Countable) (hd : S.Pairwise Disjoint)
(h : ∀ s ∈ S, MeasurableSet s) : μ (⋃₀ S) = ∑' s : S, μ s := by
rw [sUnion_eq_biUnion, measure_biUnion hs hd h]
#align measure_theory.measure_sUnion MeasureTheory.measure_sUnion
theorem measure_biUnion_finset₀ {s : Finset ι} {f : ι → Set α}
(hd : Set.Pairwise (↑s) (AEDisjoint μ on f)) (hm : ∀ b ∈ s, NullMeasurableSet (f b) μ) :
μ (⋃ b ∈ s, f b) = ∑ p ∈ s, μ (f p) := by
rw [← Finset.sum_attach, Finset.attach_eq_univ, ← tsum_fintype]
exact measure_biUnion₀ s.countable_toSet hd hm
#align measure_theory.measure_bUnion_finset₀ MeasureTheory.measure_biUnion_finset₀
theorem measure_biUnion_finset {s : Finset ι} {f : ι → Set α} (hd : PairwiseDisjoint (↑s) f)
(hm : ∀ b ∈ s, MeasurableSet (f b)) : μ (⋃ b ∈ s, f b) = ∑ p ∈ s, μ (f p) :=
measure_biUnion_finset₀ hd.aedisjoint fun b hb => (hm b hb).nullMeasurableSet
#align measure_theory.measure_bUnion_finset MeasureTheory.measure_biUnion_finset
theorem tsum_meas_le_meas_iUnion_of_disjoint₀ {ι : Type*} [MeasurableSpace α] (μ : Measure α)
{As : ι → Set α} (As_mble : ∀ i : ι, NullMeasurableSet (As i) μ)
(As_disj : Pairwise (AEDisjoint μ on As)) : (∑' i, μ (As i)) ≤ μ (⋃ i, As i) := by
rw [ENNReal.tsum_eq_iSup_sum, iSup_le_iff]
intro s
simp only [← measure_biUnion_finset₀ (fun _i _hi _j _hj hij => As_disj hij) fun i _ => As_mble i]
gcongr
exact iUnion_subset fun _ ↦ Subset.rfl
theorem tsum_meas_le_meas_iUnion_of_disjoint {ι : Type*} [MeasurableSpace α] (μ : Measure α)
{As : ι → Set α} (As_mble : ∀ i : ι, MeasurableSet (As i))
(As_disj : Pairwise (Disjoint on As)) : (∑' i, μ (As i)) ≤ μ (⋃ i, As i) :=
tsum_meas_le_meas_iUnion_of_disjoint₀ μ (fun i ↦ (As_mble i).nullMeasurableSet)
(fun _ _ h ↦ Disjoint.aedisjoint (As_disj h))
#align measure_theory.tsum_meas_le_meas_Union_of_disjoint MeasureTheory.tsum_meas_le_meas_iUnion_of_disjoint
theorem tsum_measure_preimage_singleton {s : Set β} (hs : s.Countable) {f : α → β}
(hf : ∀ y ∈ s, MeasurableSet (f ⁻¹' {y})) : (∑' b : s, μ (f ⁻¹' {↑b})) = μ (f ⁻¹' s) := by
rw [← Set.biUnion_preimage_singleton, measure_biUnion hs (pairwiseDisjoint_fiber f s) hf]
#align measure_theory.tsum_measure_preimage_singleton MeasureTheory.tsum_measure_preimage_singleton
lemma measure_preimage_eq_zero_iff_of_countable {s : Set β} {f : α → β} (hs : s.Countable) :
μ (f ⁻¹' s) = 0 ↔ ∀ x ∈ s, μ (f ⁻¹' {x}) = 0 := by
rw [← biUnion_preimage_singleton, measure_biUnion_null_iff hs]
theorem sum_measure_preimage_singleton (s : Finset β) {f : α → β}
(hf : ∀ y ∈ s, MeasurableSet (f ⁻¹' {y})) : (∑ b ∈ s, μ (f ⁻¹' {b})) = μ (f ⁻¹' ↑s) := by
simp only [← measure_biUnion_finset (pairwiseDisjoint_fiber f s) hf,
Finset.set_biUnion_preimage_singleton]
#align measure_theory.sum_measure_preimage_singleton MeasureTheory.sum_measure_preimage_singleton
theorem measure_diff_null' (h : μ (s₁ ∩ s₂) = 0) : μ (s₁ \ s₂) = μ s₁ :=
measure_congr <| diff_ae_eq_self.2 h
#align measure_theory.measure_diff_null' MeasureTheory.measure_diff_null'
theorem measure_add_diff (hs : MeasurableSet s) (t : Set α) : μ s + μ (t \ s) = μ (s ∪ t) := by
rw [← measure_union' disjoint_sdiff_right hs, union_diff_self]
#align measure_theory.measure_add_diff MeasureTheory.measure_add_diff
theorem measure_diff' (s : Set α) (hm : MeasurableSet t) (h_fin : μ t ≠ ∞) :
μ (s \ t) = μ (s ∪ t) - μ t :=
Eq.symm <| ENNReal.sub_eq_of_add_eq h_fin <| by rw [add_comm, measure_add_diff hm, union_comm]
#align measure_theory.measure_diff' MeasureTheory.measure_diff'
theorem measure_diff (h : s₂ ⊆ s₁) (h₂ : MeasurableSet s₂) (h_fin : μ s₂ ≠ ∞) :
μ (s₁ \ s₂) = μ s₁ - μ s₂ := by rw [measure_diff' _ h₂ h_fin, union_eq_self_of_subset_right h]
#align measure_theory.measure_diff MeasureTheory.measure_diff
theorem le_measure_diff : μ s₁ - μ s₂ ≤ μ (s₁ \ s₂) :=
tsub_le_iff_left.2 <| (measure_le_inter_add_diff μ s₁ s₂).trans <| by
gcongr; apply inter_subset_right
#align measure_theory.le_measure_diff MeasureTheory.le_measure_diff
theorem measure_eq_top_iff_of_symmDiff (hμst : μ (s ∆ t) ≠ ∞) : μ s = ∞ ↔ μ t = ∞ := by
suffices h : ∀ u v, μ (u ∆ v) ≠ ∞ → μ u = ∞ → μ v = ∞
from ⟨h s t hμst, h t s (symmDiff_comm s t ▸ hμst)⟩
intro u v hμuv hμu
by_contra! hμv
apply hμuv
rw [Set.symmDiff_def, eq_top_iff]
calc
∞ = μ u - μ v := (WithTop.sub_eq_top_iff.2 ⟨hμu, hμv⟩).symm
_ ≤ μ (u \ v) := le_measure_diff
_ ≤ μ (u \ v ∪ v \ u) := measure_mono subset_union_left
theorem measure_ne_top_iff_of_symmDiff (hμst : μ (s ∆ t) ≠ ∞) : μ s ≠ ∞ ↔ μ t ≠ ∞ :=
(measure_eq_top_iff_of_symmDiff hμst).ne
theorem measure_diff_lt_of_lt_add (hs : MeasurableSet s) (hst : s ⊆ t) (hs' : μ s ≠ ∞) {ε : ℝ≥0∞}
(h : μ t < μ s + ε) : μ (t \ s) < ε := by
rw [measure_diff hst hs hs']; rw [add_comm] at h
exact ENNReal.sub_lt_of_lt_add (measure_mono hst) h
#align measure_theory.measure_diff_lt_of_lt_add MeasureTheory.measure_diff_lt_of_lt_add
theorem measure_diff_le_iff_le_add (hs : MeasurableSet s) (hst : s ⊆ t) (hs' : μ s ≠ ∞) {ε : ℝ≥0∞} :
μ (t \ s) ≤ ε ↔ μ t ≤ μ s + ε := by rw [measure_diff hst hs hs', tsub_le_iff_left]
#align measure_theory.measure_diff_le_iff_le_add MeasureTheory.measure_diff_le_iff_le_add
theorem measure_eq_measure_of_null_diff {s t : Set α} (hst : s ⊆ t) (h_nulldiff : μ (t \ s) = 0) :
μ s = μ t := measure_congr <|
EventuallyLE.antisymm (HasSubset.Subset.eventuallyLE hst) (ae_le_set.mpr h_nulldiff)
#align measure_theory.measure_eq_measure_of_null_diff MeasureTheory.measure_eq_measure_of_null_diff
theorem measure_eq_measure_of_between_null_diff {s₁ s₂ s₃ : Set α} (h12 : s₁ ⊆ s₂) (h23 : s₂ ⊆ s₃)
(h_nulldiff : μ (s₃ \ s₁) = 0) : μ s₁ = μ s₂ ∧ μ s₂ = μ s₃ := by
have le12 : μ s₁ ≤ μ s₂ := measure_mono h12
have le23 : μ s₂ ≤ μ s₃ := measure_mono h23
have key : μ s₃ ≤ μ s₁ :=
calc
μ s₃ = μ (s₃ \ s₁ ∪ s₁) := by rw [diff_union_of_subset (h12.trans h23)]
_ ≤ μ (s₃ \ s₁) + μ s₁ := measure_union_le _ _
_ = μ s₁ := by simp only [h_nulldiff, zero_add]
exact ⟨le12.antisymm (le23.trans key), le23.antisymm (key.trans le12)⟩
#align measure_theory.measure_eq_measure_of_between_null_diff MeasureTheory.measure_eq_measure_of_between_null_diff
theorem measure_eq_measure_smaller_of_between_null_diff {s₁ s₂ s₃ : Set α} (h12 : s₁ ⊆ s₂)
(h23 : s₂ ⊆ s₃) (h_nulldiff : μ (s₃ \ s₁) = 0) : μ s₁ = μ s₂ :=
(measure_eq_measure_of_between_null_diff h12 h23 h_nulldiff).1
#align measure_theory.measure_eq_measure_smaller_of_between_null_diff MeasureTheory.measure_eq_measure_smaller_of_between_null_diff
theorem measure_eq_measure_larger_of_between_null_diff {s₁ s₂ s₃ : Set α} (h12 : s₁ ⊆ s₂)
(h23 : s₂ ⊆ s₃) (h_nulldiff : μ (s₃ \ s₁) = 0) : μ s₂ = μ s₃ :=
(measure_eq_measure_of_between_null_diff h12 h23 h_nulldiff).2
#align measure_theory.measure_eq_measure_larger_of_between_null_diff MeasureTheory.measure_eq_measure_larger_of_between_null_diff
lemma measure_compl₀ (h : NullMeasurableSet s μ) (hs : μ s ≠ ∞) :
μ sᶜ = μ Set.univ - μ s := by
rw [← measure_add_measure_compl₀ h, ENNReal.add_sub_cancel_left hs]
theorem measure_compl (h₁ : MeasurableSet s) (h_fin : μ s ≠ ∞) : μ sᶜ = μ univ - μ s :=
measure_compl₀ h₁.nullMeasurableSet h_fin
#align measure_theory.measure_compl MeasureTheory.measure_compl
lemma measure_inter_conull' (ht : μ (s \ t) = 0) : μ (s ∩ t) = μ s := by
rw [← diff_compl, measure_diff_null']; rwa [← diff_eq]
lemma measure_inter_conull (ht : μ tᶜ = 0) : μ (s ∩ t) = μ s := by
rw [← diff_compl, measure_diff_null ht]
@[simp]
theorem union_ae_eq_left_iff_ae_subset : (s ∪ t : Set α) =ᵐ[μ] s ↔ t ≤ᵐ[μ] s := by
rw [ae_le_set]
refine
⟨fun h => by simpa only [union_diff_left] using (ae_eq_set.mp h).1, fun h =>
eventuallyLE_antisymm_iff.mpr
⟨by rwa [ae_le_set, union_diff_left],
HasSubset.Subset.eventuallyLE subset_union_left⟩⟩
#align measure_theory.union_ae_eq_left_iff_ae_subset MeasureTheory.union_ae_eq_left_iff_ae_subset
@[simp]
theorem union_ae_eq_right_iff_ae_subset : (s ∪ t : Set α) =ᵐ[μ] t ↔ s ≤ᵐ[μ] t := by
rw [union_comm, union_ae_eq_left_iff_ae_subset]
#align measure_theory.union_ae_eq_right_iff_ae_subset MeasureTheory.union_ae_eq_right_iff_ae_subset
theorem ae_eq_of_ae_subset_of_measure_ge (h₁ : s ≤ᵐ[μ] t) (h₂ : μ t ≤ μ s) (hsm : MeasurableSet s)
(ht : μ t ≠ ∞) : s =ᵐ[μ] t := by
refine eventuallyLE_antisymm_iff.mpr ⟨h₁, ae_le_set.mpr ?_⟩
replace h₂ : μ t = μ s := h₂.antisymm (measure_mono_ae h₁)
replace ht : μ s ≠ ∞ := h₂ ▸ ht
rw [measure_diff' t hsm ht, measure_congr (union_ae_eq_left_iff_ae_subset.mpr h₁), h₂, tsub_self]
#align measure_theory.ae_eq_of_ae_subset_of_measure_ge MeasureTheory.ae_eq_of_ae_subset_of_measure_ge
theorem ae_eq_of_subset_of_measure_ge (h₁ : s ⊆ t) (h₂ : μ t ≤ μ s) (hsm : MeasurableSet s)
(ht : μ t ≠ ∞) : s =ᵐ[μ] t :=
ae_eq_of_ae_subset_of_measure_ge (HasSubset.Subset.eventuallyLE h₁) h₂ hsm ht
#align measure_theory.ae_eq_of_subset_of_measure_ge MeasureTheory.ae_eq_of_subset_of_measure_ge
theorem measure_iUnion_congr_of_subset [Countable β] {s : β → Set α} {t : β → Set α}
(hsub : ∀ b, s b ⊆ t b) (h_le : ∀ b, μ (t b) ≤ μ (s b)) : μ (⋃ b, s b) = μ (⋃ b, t b) := by
rcases Classical.em (∃ b, μ (t b) = ∞) with (⟨b, hb⟩ | htop)
· calc
μ (⋃ b, s b) = ∞ := top_unique (hb ▸ (h_le b).trans <| measure_mono <| subset_iUnion _ _)
_ = μ (⋃ b, t b) := Eq.symm <| top_unique <| hb ▸ measure_mono (subset_iUnion _ _)
push_neg at htop
refine le_antisymm (measure_mono (iUnion_mono hsub)) ?_
set M := toMeasurable μ
have H : ∀ b, (M (t b) ∩ M (⋃ b, s b) : Set α) =ᵐ[μ] M (t b) := by
refine fun b => ae_eq_of_subset_of_measure_ge inter_subset_left ?_ ?_ ?_
· calc
μ (M (t b)) = μ (t b) := measure_toMeasurable _
_ ≤ μ (s b) := h_le b
_ ≤ μ (M (t b) ∩ M (⋃ b, s b)) :=
measure_mono <|
subset_inter ((hsub b).trans <| subset_toMeasurable _ _)
((subset_iUnion _ _).trans <| subset_toMeasurable _ _)
· exact (measurableSet_toMeasurable _ _).inter (measurableSet_toMeasurable _ _)
· rw [measure_toMeasurable]
exact htop b
calc
μ (⋃ b, t b) ≤ μ (⋃ b, M (t b)) := measure_mono (iUnion_mono fun b => subset_toMeasurable _ _)
_ = μ (⋃ b, M (t b) ∩ M (⋃ b, s b)) := measure_congr (EventuallyEq.countable_iUnion H).symm
_ ≤ μ (M (⋃ b, s b)) := measure_mono (iUnion_subset fun b => inter_subset_right)
_ = μ (⋃ b, s b) := measure_toMeasurable _
#align measure_theory.measure_Union_congr_of_subset MeasureTheory.measure_iUnion_congr_of_subset
theorem measure_union_congr_of_subset {t₁ t₂ : Set α} (hs : s₁ ⊆ s₂) (hsμ : μ s₂ ≤ μ s₁)
(ht : t₁ ⊆ t₂) (htμ : μ t₂ ≤ μ t₁) : μ (s₁ ∪ t₁) = μ (s₂ ∪ t₂) := by
rw [union_eq_iUnion, union_eq_iUnion]
exact measure_iUnion_congr_of_subset (Bool.forall_bool.2 ⟨ht, hs⟩) (Bool.forall_bool.2 ⟨htμ, hsμ⟩)
#align measure_theory.measure_union_congr_of_subset MeasureTheory.measure_union_congr_of_subset
@[simp]
theorem measure_iUnion_toMeasurable [Countable β] (s : β → Set α) :
μ (⋃ b, toMeasurable μ (s b)) = μ (⋃ b, s b) :=
Eq.symm <|
measure_iUnion_congr_of_subset (fun _b => subset_toMeasurable _ _) fun _b =>
(measure_toMeasurable _).le
#align measure_theory.measure_Union_to_measurable MeasureTheory.measure_iUnion_toMeasurable
theorem measure_biUnion_toMeasurable {I : Set β} (hc : I.Countable) (s : β → Set α) :
μ (⋃ b ∈ I, toMeasurable μ (s b)) = μ (⋃ b ∈ I, s b) := by
haveI := hc.toEncodable
simp only [biUnion_eq_iUnion, measure_iUnion_toMeasurable]
#align measure_theory.measure_bUnion_to_measurable MeasureTheory.measure_biUnion_toMeasurable
@[simp]
theorem measure_toMeasurable_union : μ (toMeasurable μ s ∪ t) = μ (s ∪ t) :=
Eq.symm <|
measure_union_congr_of_subset (subset_toMeasurable _ _) (measure_toMeasurable _).le Subset.rfl
le_rfl
#align measure_theory.measure_to_measurable_union MeasureTheory.measure_toMeasurable_union
@[simp]
theorem measure_union_toMeasurable : μ (s ∪ toMeasurable μ t) = μ (s ∪ t) :=
Eq.symm <|
measure_union_congr_of_subset Subset.rfl le_rfl (subset_toMeasurable _ _)
(measure_toMeasurable _).le
#align measure_theory.measure_union_to_measurable MeasureTheory.measure_union_toMeasurable
theorem sum_measure_le_measure_univ {s : Finset ι} {t : ι → Set α}
(h : ∀ i ∈ s, MeasurableSet (t i)) (H : Set.PairwiseDisjoint (↑s) t) :
(∑ i ∈ s, μ (t i)) ≤ μ (univ : Set α) := by
rw [← measure_biUnion_finset H h]
exact measure_mono (subset_univ _)
#align measure_theory.sum_measure_le_measure_univ MeasureTheory.sum_measure_le_measure_univ
theorem tsum_measure_le_measure_univ {s : ι → Set α} (hs : ∀ i, MeasurableSet (s i))
(H : Pairwise (Disjoint on s)) : (∑' i, μ (s i)) ≤ μ (univ : Set α) := by
rw [ENNReal.tsum_eq_iSup_sum]
exact iSup_le fun s =>
sum_measure_le_measure_univ (fun i _hi => hs i) fun i _hi j _hj hij => H hij
#align measure_theory.tsum_measure_le_measure_univ MeasureTheory.tsum_measure_le_measure_univ
| Mathlib/MeasureTheory/Measure/MeasureSpace.lean | 425 | 431 | theorem exists_nonempty_inter_of_measure_univ_lt_tsum_measure {m : MeasurableSpace α}
(μ : Measure α) {s : ι → Set α} (hs : ∀ i, MeasurableSet (s i))
(H : μ (univ : Set α) < ∑' i, μ (s i)) : ∃ i j, i ≠ j ∧ (s i ∩ s j).Nonempty := by |
contrapose! H
apply tsum_measure_le_measure_univ hs
intro i j hij
exact disjoint_iff_inter_eq_empty.mpr (H i j hij)
|
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
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
#align algebraic_geometry.LocallyRingedSpace.to_Γ_Spec_continuous AlgebraicGeometry.LocallyRingedSpace.toΓSpec_continuous
@[simps]
def toΓSpecBase : X.toTopCat ⟶ Spec.topObj (Γ.obj (op X)) where
toFun := X.toΓSpecFun
continuous_toFun := X.toΓSpec_continuous
#align algebraic_geometry.LocallyRingedSpace.to_Γ_Spec_base AlgebraicGeometry.LocallyRingedSpace.toΓSpecBase
-- These lemmas have always been bad (#7657), but lean4#2644 made `simp` start noticing
attribute [nolint simpNF] AlgebraicGeometry.LocallyRingedSpace.toΓSpecBase_apply
variable (r : Γ.obj (op X))
abbrev toΓSpecMapBasicOpen : Opens X :=
(Opens.map X.toΓSpecBase).obj (basicOpen r)
#align algebraic_geometry.LocallyRingedSpace.to_Γ_Spec_map_basic_open AlgebraicGeometry.LocallyRingedSpace.toΓSpecMapBasicOpen
theorem toΓSpecMapBasicOpen_eq : X.toΓSpecMapBasicOpen r = X.toRingedSpace.basicOpen r :=
Opens.ext (X.toΓSpec_preim_basicOpen_eq r)
#align algebraic_geometry.LocallyRingedSpace.to_Γ_Spec_map_basic_open_eq AlgebraicGeometry.LocallyRingedSpace.toΓSpecMapBasicOpen_eq
abbrev toToΓSpecMapBasicOpen :
X.presheaf.obj (op ⊤) ⟶ X.presheaf.obj (op <| X.toΓSpecMapBasicOpen r) :=
X.presheaf.map (X.toΓSpecMapBasicOpen r).leTop.op
#align algebraic_geometry.LocallyRingedSpace.to_to_Γ_Spec_map_basic_open AlgebraicGeometry.LocallyRingedSpace.toToΓSpecMapBasicOpen
theorem isUnit_res_toΓSpecMapBasicOpen : IsUnit (X.toToΓSpecMapBasicOpen r r) := by
convert
(X.presheaf.map <| (eqToHom <| X.toΓSpecMapBasicOpen_eq r).op).isUnit_map
(X.toRingedSpace.isUnit_res_basicOpen r)
-- Porting note: `rw [comp_apply]` to `erw [comp_apply]`
erw [← comp_apply, ← Functor.map_comp]
congr
#align algebraic_geometry.LocallyRingedSpace.is_unit_res_to_Γ_Spec_map_basic_open AlgebraicGeometry.LocallyRingedSpace.isUnit_res_toΓSpecMapBasicOpen
def toΓSpecCApp :
(structureSheaf <| Γ.obj <| op X).val.obj (op <| basicOpen r) ⟶
X.presheaf.obj (op <| X.toΓSpecMapBasicOpen r) :=
IsLocalization.Away.lift r (isUnit_res_toΓSpecMapBasicOpen _ r)
#align algebraic_geometry.LocallyRingedSpace.to_Γ_Spec_c_app AlgebraicGeometry.LocallyRingedSpace.toΓSpecCApp
theorem toΓSpecCApp_iff
(f :
(structureSheaf <| Γ.obj <| op X).val.obj (op <| basicOpen r) ⟶
X.presheaf.obj (op <| X.toΓSpecMapBasicOpen r)) :
toOpen _ (basicOpen r) ≫ f = X.toToΓSpecMapBasicOpen r ↔ f = X.toΓSpecCApp r := by
-- Porting Note: Type class problem got stuck in `IsLocalization.Away.AwayMap.lift_comp`
-- created instance manually. This replaces the `pick_goal` tactics
have loc_inst := IsLocalization.to_basicOpen (Γ.obj (op X)) r
rw [← @IsLocalization.Away.AwayMap.lift_comp _ _ _ _ _ _ _ r loc_inst _
(X.isUnit_res_toΓSpecMapBasicOpen r)]
--pick_goal 5; exact is_localization.to_basic_open _ r
constructor
· intro h
exact IsLocalization.ringHom_ext (Submonoid.powers r) h
apply congr_arg
#align algebraic_geometry.LocallyRingedSpace.to_Γ_Spec_c_app_iff AlgebraicGeometry.LocallyRingedSpace.toΓSpecCApp_iff
theorem toΓSpecCApp_spec : toOpen _ (basicOpen r) ≫ X.toΓSpecCApp r = X.toToΓSpecMapBasicOpen r :=
(X.toΓSpecCApp_iff r _).2 rfl
#align algebraic_geometry.LocallyRingedSpace.to_Γ_Spec_c_app_spec AlgebraicGeometry.LocallyRingedSpace.toΓSpecCApp_spec
@[simps app]
def toΓSpecCBasicOpens :
(inducedFunctor basicOpen).op ⋙ (structureSheaf (Γ.obj (op X))).1 ⟶
(inducedFunctor basicOpen).op ⋙ ((TopCat.Sheaf.pushforward _ X.toΓSpecBase).obj X.𝒪).1 where
app r := X.toΓSpecCApp r.unop
naturality r s f := by
apply (StructureSheaf.to_basicOpen_epi (Γ.obj (op X)) r.unop).1
simp only [← Category.assoc]
erw [X.toΓSpecCApp_spec r.unop]
convert X.toΓSpecCApp_spec s.unop
symm
apply X.presheaf.map_comp
#align algebraic_geometry.LocallyRingedSpace.to_Γ_Spec_c_basic_opens AlgebraicGeometry.LocallyRingedSpace.toΓSpecCBasicOpens
@[simps]
def toΓSpecSheafedSpace : X.toSheafedSpace ⟶ Spec.toSheafedSpace.obj (op (Γ.obj (op X))) where
base := X.toΓSpecBase
c :=
TopCat.Sheaf.restrictHomEquivHom (structureSheaf (Γ.obj (op X))).1 _ isBasis_basic_opens
X.toΓSpecCBasicOpens
#align algebraic_geometry.LocallyRingedSpace.to_Γ_Spec_SheafedSpace AlgebraicGeometry.LocallyRingedSpace.toΓSpecSheafedSpace
-- Porting Note: Now need much more hand holding: all variables explicit, and need to tidy up
-- significantly, was `TopCat.Sheaf.extend_hom_app _ _ _ _`
theorem toΓSpecSheafedSpace_app_eq :
X.toΓSpecSheafedSpace.c.app (op (basicOpen r)) = X.toΓSpecCApp r := by
have := TopCat.Sheaf.extend_hom_app (Spec.toSheafedSpace.obj (op (Γ.obj (op X)))).presheaf
((TopCat.Sheaf.pushforward _ X.toΓSpecBase).obj X.𝒪)
isBasis_basic_opens X.toΓSpecCBasicOpens r
dsimp at this
rw [← this]
dsimp
#align algebraic_geometry.LocallyRingedSpace.to_Γ_Spec_SheafedSpace_app_eq AlgebraicGeometry.LocallyRingedSpace.toΓSpecSheafedSpace_app_eq
-- Porting note: need a helper lemma `toΓSpecSheafedSpace_app_spec_assoc` to help compile
-- `toStalk_stalkMap_to_Γ_Spec`
@[reassoc] theorem toΓSpecSheafedSpace_app_spec (r : Γ.obj (op X)) :
toOpen (Γ.obj (op X)) (basicOpen r) ≫ X.toΓSpecSheafedSpace.c.app (op (basicOpen r)) =
X.toToΓSpecMapBasicOpen r :=
(X.toΓSpecSheafedSpace_app_eq r).symm ▸ X.toΓSpecCApp_spec r
#align algebraic_geometry.LocallyRingedSpace.to_Γ_Spec_SheafedSpace_app_spec AlgebraicGeometry.LocallyRingedSpace.toΓSpecSheafedSpace_app_spec
| Mathlib/AlgebraicGeometry/GammaSpecAdjunction.lean | 214 | 226 | theorem toStalk_stalkMap_toΓSpec (x : X) :
toStalk _ _ ≫ PresheafedSpace.stalkMap X.toΓSpecSheafedSpace x = X.ΓToStalk x := by |
rw [PresheafedSpace.stalkMap]
erw [← toOpen_germ _ (basicOpen (1 : Γ.obj (op X)))
⟨X.toΓSpecFun x, by rw [basicOpen_one]; trivial⟩]
rw [← Category.assoc, Category.assoc (toOpen _ _)]
erw [stalkFunctor_map_germ]
rw [← Category.assoc, toΓSpecSheafedSpace_app_spec]
unfold ΓToStalk
rw [← stalkPushforward_germ _ X.toΓSpecBase X.presheaf ⊤]
congr 1
change (X.toΓSpecBase _* X.presheaf).map le_top.hom.op ≫ _ = _
apply germ_res
|
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