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import OAI.Analysis.DiamondDistortion.DirectEnergy
namespace OAI
universe u v
noncomputable section
open scoped BigOperators Classical Topology
open Set
namespace DiamondDistortion
open scoped ENNReal
namespace LpCut
variable {ι : Type*} {p : ℝ≥0∞} [Fact (1 ≤ p)]
def linear (H : ι → Prop) [DecidablePred H] : lp (fun _ : ι => ℝ) p →ₗ[ℝ] lp (fun _ : ι => ℝ) p where
toFun v := ⟨fun i => if H i then v i else 0,v.property.mono' (fun i => by split_ifs <;> simp)⟩
map_add' u v := by
ext i
change (if H i then u i+v i else 0)=(if H i then u i else 0)+(if H i then v i else 0)
by_cases h : H i <;> simp [h]
map_smul' c v := by ext i; by_cases h : H i <;> simp [h]
lemma linear_apply {ι : Type*} {p : ℝ≥0∞} [Fact (1 ≤ p)] (H : ι → Prop) [DecidablePred H] (v : lp (fun _ : ι => ℝ) p) (i : ι) :
linear H v i=if H i then v i else 0 := rfl
lemma norm_linear (H : ι → Prop) [DecidablePred H] (v : lp (fun _ : ι => ℝ) p) : ‖linear H v‖ ≤ ‖v‖ := by
apply lp.norm_mono (ne_of_gt (lt_of_lt_of_le zero_lt_one (Fact.out : 1 ≤ p)))
intro i
rw [linear_apply]
split_ifs <;> simp
def continuous (H : ι → Prop) [DecidablePred H] : lp (fun _ : ι => ℝ) p →L[ℝ] lp (fun _ : ι => ℝ) p :=
(linear H).mkContinuous 1 (fun v => by simpa only [one_mul] using norm_linear H v)
lemma continuous_apply (H : ι → Prop) [DecidablePred H] (v : lp (fun _ : ι => ℝ) p) (i : ι) :
continuous H v i=if H i then v i else 0 := rfl
end LpCut
namespace RecursiveModel
lemma ancestors_linear (h : ℕ) {a b c : Coord h}
(ha : a ∈ ancestors h c) (hb : b ∈ ancestors h c) :
a ∈ ancestors h b ∨ b ∈ ancestors h a := by
induction h with
| zero => left; exact self_mem_ancestors _ _
| succ h ih =>
cases c with
| inl u =>
have hak : a=Sum.inl () := by simpa only [ancestors,Finset.mem_singleton] using ha
have hbk : b=Sum.inl () := by simpa only [ancestors,Finset.mem_singleton] using hb
subst a; subst b
exact Or.inl (self_mem_ancestors _ _)
| inr q =>
rcases Finset.mem_insert.mp ha with ha|ha
· subst a
rcases Finset.mem_insert.mp hb with hb|hb
· subst b; exact Or.inl (self_mem_ancestors _ _)
· obtain ⟨b',hb',rfl⟩ := Finset.mem_image.mp hb
exact Or.inl (Finset.mem_insert_self _ _)
· obtain ⟨a',ha',rfl⟩ := Finset.mem_image.mp ha
rcases Finset.mem_insert.mp hb with hb|hb
· subst b; exact Or.inr (Finset.mem_insert_self _ _)
· obtain ⟨b',hb',rfl⟩ := Finset.mem_image.mp hb
rcases ih ha' hb' with h|h
· exact Or.inl (Finset.mem_insert_of_mem (Finset.mem_image.mpr ⟨a',h,rfl⟩))
· exact Or.inr (Finset.mem_insert_of_mem (Finset.mem_image.mpr ⟨b',h,rfl⟩))
lemma ancestral_prefix (h : ℕ) (H : Coord h → Prop) [DecidablePred H]
(hH : ∀ a b,H b → a ∈ ancestors h b → H a) (s : Coord h) :
(ancestors h s).filter H=∅ ∨ ∃ t,(ancestors h s).filter H=ancestors h t := by
let S := (ancestors h s).filter H
by_cases hn : S.Nonempty
· obtain ⟨t,ht,hmax⟩ := Finset.exists_max_image S (fun t => (ancestors h t).card) hn
refine Or.inr ⟨t,?_⟩
apply Finset.Subset.antisymm
· intro r hr
have hrs := (Finset.mem_filter.mp hr).1
have hts := (Finset.mem_filter.mp ht).1
rcases ancestors_linear h hrs hts with he|he
· exact he
· have hs : ancestors h t ⊆ ancestors h r := fun _ hk => ancestor_trans h hk he
have hc := hmax r hr
have heq := Finset.eq_of_subset_of_card_le hs hc
rw [heq]
exact self_mem_ancestors h r
· intro r hr
exact Finset.mem_filter.mpr ⟨ancestor_trans h hr (Finset.mem_filter.mp ht).1,
hH r t (Finset.mem_filter.mp ht).2 hr⟩
· exact Or.inl (Finset.not_nonempty_iff_eq_empty.mp hn)
end RecursiveModel
namespace PathModel
open RecursiveModel
lemma cut_branch (h : ℕ) (H : Coord h → Prop) [DecidablePred H]
(hH : ∀ a b,H b → a ∈ ancestors h b → H a) (s : Coord h) :
LpCut.continuous H (branch h s)=0 ∨ ∃ t,LpCut.continuous H (branch h s)=branch h t := by
rcases ancestral_prefix h H hH s with he|⟨t,he⟩
· left
ext r
rw [LpCut.continuous_apply,branch_apply]
by_cases hr : H r
· rw [ite_eq_left hr,ite_eq_right (by
intro hh
have hk := Finset.mem_filter.mpr ⟨hh,hr⟩
rw [he] at hk
exact Finset.notMem_empty r hk)]
rfl
· rw [ite_eq_right hr]; rfl
· right
refine ⟨t,?_⟩
ext r
rw [LpCut.continuous_apply,branch_apply,branch_apply]
have hm : r ∈ ancestors h t ↔ r ∈ ancestors h s ∧ H r := by rw [← he,Finset.mem_filter]
by_cases h₁ : H r <;> by_cases h₂ : r ∈ ancestors h s <;> simp [h₁,h₂,hm]
lemma branch_cost (h : ℕ) (s : Coord h) : cost 1 h (branch h s) ≤ 1 := by
have hh := (presentation 1 h).le_representation (d := WithLp.toLp 1 ((0 : L2 h),lp.single 1 s (1:ℝ)))
(show (presentation 1 h).output (WithLp.toLp 1 (0,lp.single 1 s (1:ℝ)))=branch h s by
change 0+path h (lp.single 1 s 1)=_
rw [zero_add,path_single,one_smul])
simpa only [WithLp.prod_norm_eq_of_L1,WithLp.fst,WithLp.snd,WithLp.ofLp_toLp,norm_zero,zero_add,
lp.norm_single (by norm_num : (0:ℝ≥0∞)<1),norm_one,cost] using hh
lemma linear_cost_cut (h : ℕ) (H : Coord h → Prop) [DecidablePred H]
(hH : ∀ a b,H b → a ∈ ancestors h b → H a) (v : L2 h) :
cost 1 h (LpCut.continuous H v) ≤ cost 1 h v := by
let E := linearFullData h
let T : L2 h →L[ℝ] E.Space := E.equiv.symm.toContinuousLinearMap.comp (LpCut.continuous H)
have hbranch (s : Coord h) : ‖T (branch h s)‖ ≤ 1 := by
change cost 1 h (LpCut.continuous H (branch h s)) ≤ 1
rcases cut_branch h H hH s with he|⟨t,he⟩
· rw [he,map_zero]; norm_num
· rw [he]; exact branch_cost h t
have hp (μ : L1 h) : cost 1 h (LpCut.continuous H (path h μ)) ≤ ‖μ‖ := by
have hnorm : Summable (fun s => ‖μ s • T (branch h s)‖) := by
apply Summable.of_nonneg_of_le (fun _ => norm_nonneg _) _ (summable_abs μ)
intro s
rw [norm_smul,Real.norm_eq_abs]
exact (mul_le_mul_of_nonneg_left (hbranch s) (abs_nonneg _)).trans_eq (mul_one _)
have hsum := (path_summable μ).hasSum.mapL T
simp_rw [map_smul] at hsum
change ‖T (path h μ)‖ ≤ ‖μ‖
change ‖T (∑' s,μ s • branch h s)‖ ≤ ‖μ‖
rw [← hsum.tsum_eq]
calc
_ ≤ ∑' s,‖μ s • T (branch h s)‖ := norm_tsum_le_tsum_norm hnorm
_ ≤ ∑' s,|μ s| := Summable.tsum_le_tsum (fun s => by
rw [norm_smul,Real.norm_eq_abs]
exact (mul_le_mul_of_nonneg_left (hbranch s) (abs_nonneg _)).trans_eq (mul_one _)) hnorm (summable_abs μ)
_ = ‖μ‖ := tsum_abs μ
have hb := (presentation 1 h).bound v (by norm_num : (0:ℝ) ≤ 1) (b := cost 1 h (LpCut.continuous H v))
simp only [one_mul] at hb
apply hb
intro d hd
change d.fst+path h d.snd=v at hd
rw [← hd,map_add,WithLp.prod_norm_eq_of_L1]
exact (map_add_le_add (cost 1 h) _ _).trans (add_le_add
((linear_le_norm _ _).trans (LpCut.norm_linear _ _)) (hp d.snd))
end PathModel
namespace CoordinateCompletion.Data
variable {ι : Type*} (A : CoordinateCompletion.Data ι)
lemma projection_nested (H B : Finset ι) (hHB : H ⊆ B) (x : A.Space) :
A.projection H (A.projection B x)=A.projection H x := by
rw [A.projection_apply H (A.projection B x)]
simp only [coordinate_projection]
rw [A.projection_apply H x]
apply Finset.sum_congr rfl
intro i hi
rw [ite_eq_left (hHB hi)]
lemma projection_nested_right (H B : Finset ι) (hHB : H ⊆ B) (x : A.Space) :
A.projection B (A.projection H x)=A.projection H x := by
rw [A.projection_commutes B H]
exact A.projection_nested H B hHB x
end CoordinateCompletion.Data
namespace RecursiveModel
instance : PartialOrder ForestHead := inferInstanceAs (PartialOrder {H : Finset ForestCoord // ∀ i ∈ H,forestAncestors i ⊆ H})
lemma head_upper (H K : ForestHead) : ∃ B : ForestHead,H ≤ B ∧ K ≤ B := by
let B : ForestHead := ⟨H.val ∪ K.val,by
intro i hi j hj
rcases Finset.mem_union.mp hi with hi|hi
· exact Finset.mem_union_left _ (H.property i hi hj)
· exact Finset.mem_union_right _ (K.property i hi hj)⟩
exact ⟨B,Finset.subset_union_left,Finset.subset_union_right⟩
lemma head_nonempty : Nonempty ForestHead := ⟨forestHead ∅⟩
end RecursiveModel
namespace PathModel
open RecursiveModel
lemma linear_forest_cut (v : ForestVec) (H : ForestHead) :
linearForestSeminorm (v.filter (· ∈ H.val)) ≤ linearForestSeminorm v := by
apply aggregate_mono 2
· exact outerValues_nonneg _ _
· intro h
rw [outerValues_apply,outerValues_apply]
change cost 1 (h+1) (finiteEmbedding _ (components (v.filter (· ∈ H.val)) h)) ≤
cost 1 (h+1) (finiteEmbedding _ (components v h))
have he : finiteEmbedding (h+1) (components (v.filter (· ∈ H.val)) h)=
LpCut.continuous (fun i : Coord (h+1) => (⟨h,i⟩ : ForestCoord) ∈ H.val)
(finiteEmbedding (h+1) (components v h)) := by
ext i
change (v.filter (· ∈ H.val)) ⟨h,i⟩=if (⟨h,i⟩ : ForestCoord) ∈ H.val then v ⟨h,i⟩ else 0
exact Finsupp.filter_apply _ _ _
rw [he]
apply linear_cost_cut
intro a b hb hab
exact H.property ⟨h,b⟩ hb (Finset.mem_image.mpr ⟨a,hab,rfl⟩)
lemma linear_projection_contractive (H : ForestHead) (x : linearData.Space) :
‖linearData.projection H.val x‖ ≤ ‖x‖ := by
rcases H with ⟨H,hH⟩
induction x using UniformSpace.Completion.induction_on with
| hp => exact isClosed_le (by fun_prop) continuous_norm
| ih v =>
change ‖linearData.projection H (linearData.embedding (linearData.array v))‖ ≤ ‖linearData.embedding (linearData.array v)‖
rw [linearData.projection_embedding,linearData.norm_embedding,linearData.norm_embedding]
convert linear_forest_cut (linearData.array v) ⟨H,hH⟩ using 1 <;> congr 1
ext i
simp only [Finsupp.filter_apply]
by_cases hi : i ∈ H <;> simp only [hi,ite_eq_left]
end PathModel
end DiamondDistortion
end
end OAI