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Add lean source and binary files (part 47)
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import Mathlib
import OAI.Combinatorics.MatchingCount.Sampling.Plan
namespace OAI
namespace MatchingFPRAS.UnitRefresh.Materialized
open Finset MatchingFPRAS.FiniteChoice MatchingFPRAS.Variation
open scoped Classical
variable {n m : ℕ}
def remainingBags (bags : Fin (n+2) → Finset (Fin m)) (a : Fin (n+2))
(c : Partner bags a) : Fin n → Finset (Fin m) :=
fun x=>bags (removePairEquiv a c.val.1 c.property.1 x).val
lemma remainingRanked (bags : Fin (n+2) → Finset (Fin m)) (rank : Fin m → ℕ)
(parent : Fin m → Option (Fin m)) (hb : RankedBags bags rank parent)
(a : Fin (n+2)) (c : Partner bags a) : RankedBags (remainingBags bags a c) rank parent := by
intro x l hl r hr
exact hb _ l hl r hr
lemma remainingNonempty (bags : Fin (n+2) → Finset (Fin m))
(hne : ∀ x,(bags x).Nonempty) (a : Fin (n+2)) (c : Partner bags a) :
∀ x,(remainingBags bags a c x).Nonempty := fun _=>hne _
lemma remainingCard (bags : Fin (n+2) → Finset (Fin m)) (rank : Fin m → ℕ)
(parent : Fin m → Option (Fin m)) (hb : RankedBags bags rank parent)
(hne : ∀ x,(bags x).Nonempty) (hp : ∀ l p,parent l=some p → rank p<rank l)
(a : Fin (n+2)) (c : Partner bags a) :
Fintype.card (ColoredPairing (remainingBags bags a c))=branchCount bags rank parent a c.val.1 := by
have h := Fintype.card_congr (ColoredPairing.equiv (residualBags bags a c.val.1)
(removePairEquiv a c.val.1 c.property.1))
exact h.trans (branchCount_eq bags rank parent hb hne hp _ _).symm
lemma remainingPositive (bags : Fin (n+2) → Finset (Fin m)) (rank : Fin m → ℕ)
(parent : Fin m → Option (Fin m)) (hb : RankedBags bags rank parent)
(hne : ∀ x,(bags x).Nonempty) (hp : ∀ l p,parent l=some p → rank p<rank l)
(a : Fin (n+2)) (c : PositivePartner bags rank parent a) :
0<count (remainingBags bags a c.val) parent (plan rank) := by
rw [computable_count_eq _ rank parent (remainingRanked bags rank parent hb a c.val)
(remainingNonempty bags hne a c.val) hp, remainingCard bags rank parent hb hne hp]
exact c.property
def assembleEdge (bags : Fin (n+2) → Finset (Fin m)) (a : Fin (n+2)) (c : Partner bags a)
(p : ColoredPairing (remainingBags bags a c)) : ColoredPairing bags :=
(ColoredPairing.map (residualBags bags a c.val.1) (removePairEquiv a c.val.1 c.property.1) p).insert a c
def residualSampler (k : ℕ) (bags : Fin (n+2) → Finset (Fin m)) (rank : Fin m → ℕ)
(parent : Fin m → Option (Fin m)) (hb : RankedBags bags rank parent)
(hne : ∀ x,(bags x).Nonempty) (hp : ∀ l p,parent l=some p → rank p<rank l)
(a : Fin (n+2)) (c : PositivePartner bags rank parent a) (bits : Fin n → Fin k → Bool) : ColoredPairing bags :=
assembleEdge bags a c.val (sampleUnit k n (remainingBags bags a c.val) rank parent
(remainingRanked bags rank parent hb a c.val) (remainingNonempty bags hne a c.val) hp
(remainingPositive bags rank parent hb hne hp a c) bits)
lemma sampleUnit_step (k : ℕ) (bags : Fin (n+2) → Finset (Fin m)) (rank : Fin m → ℕ)
(parent : Fin m → Option (Fin m)) (hb : RankedBags bags rank parent)
(hne : ∀ x,(bags x).Nonempty) (hp : ∀ l p,parent l=some p → rank p<rank l)
(hz : 0<count bags parent (plan rank)) (bits : Fin (n+2) → Fin k → Bool) :
sampleUnit k (n+2) bags rank parent hb hne hp hz bits=
residualSampler k bags rank parent hb hne hp (Fin.last (n+1))
(drawEdge bags rank parent hb hne hp (Fin.last (n+1)) hz k (bits (Fin.last (n+1))))
(fun i=>bits i.castSucc.castSucc) := rfl
noncomputable def renumberedSplitEquiv (bags : Fin (n+2) → Finset (Fin m)) (rank : Fin m → ℕ)
(parent : Fin m → Option (Fin m)) (hb : RankedBags bags rank parent)
(hne : ∀ x,(bags x).Nonempty) (hp : ∀ l p,parent l=some p → rank p<rank l)
(a : Fin (n+2)) :
(Σ c : PositivePartner bags rank parent a,ColoredPairing (remainingBags bags a c.val)) ≃ ColoredPairing bags :=
(Equiv.sigmaCongrRight (fun c : PositivePartner bags rank parent a=>
ColoredPairing.equiv (residualBags bags a c.val.val.1)
(removePairEquiv a c.val.val.1 c.val.property.1))).trans
(positiveSplitEquiv bags rank parent hb hne hp a)
lemma renumberedSplitEquiv_apply (bags : Fin (n+2) → Finset (Fin m)) (rank : Fin m → ℕ)
(parent : Fin m → Option (Fin m)) (hb : RankedBags bags rank parent)
(hne : ∀ x,(bags x).Nonempty) (hp : ∀ l p,parent l=some p → rank p<rank l)
(a : Fin (n+2)) (s : Σ c : PositivePartner bags rank parent a,ColoredPairing (remainingBags bags a c.val)) :
renumberedSplitEquiv bags rank parent hb hne hp a s=assembleEdge bags a s.1.val s.2 := rfl
lemma sampleUnit_step_law (k : ℕ) (bags : Fin (n+2) → Finset (Fin m)) (rank : Fin m → ℕ)
(parent : Fin m → Option (Fin m)) (hb : RankedBags bags rank parent)
(hne : ∀ x,(bags x).Nonempty) (hp : ∀ l p,parent l=some p → rank p<rank l)
(hz : 0<count bags parent (plan rank)) :
imageLaw (sampleUnit k (n+2) bags rank parent hb hne hp hz)=
bind (imageLaw (drawEdge bags rank parent hb hne hp (Fin.last (n+1)) hz k))
(fun c=>imageLaw (residualSampler k bags rank parent hb hne hp (Fin.last (n+1)) c)) := by
exact imageLaw_fin_skip n _ _ _ (sampleUnit_step k bags rank parent hb hne hp hz)
lemma exact_unit_step (bags : Fin (n+2) → Finset (Fin m)) (rank : Fin m → ℕ)
(parent : Fin m → Option (Fin m)) (hb : RankedBags bags rank parent)
(hne : ∀ x,(bags x).Nonempty) (hp : ∀ l p,parent l=some p → rank p<rank l)
(a : Fin (n+2)) (hz : 0<count bags parent (plan rank)) :
bind (fun c : PositivePartner bags rank parent a=>
(branchCount bags rank parent a c.val.val.1:ℝ)/count bags parent (plan rank))
(fun c : PositivePartner bags rank parent a=>
push (uniform (ColoredPairing (remainingBags bags a c.val))) (assembleEdge bags a c.val))=
uniform (ColoredPairing bags) := by
let : Nonempty (ColoredPairing bags) := Fintype.card_pos_iff.mp (by
rwa [←computable_count_eq bags rank parent hb hne hp])
have h := funext (uniform_sigma (renumberedSplitEquiv bags rank parent hb hne hp a))
rw [push_sigmaLift] at h
simpa only [remainingCard bags rank parent hb hne hp,←computable_count_eq bags rank parent hb hne hp,
renumberedSplitEquiv_apply] using h
open Finset MatchingFPRAS.Variation
open scoped Classical
variable {m n : ℕ}
lemma residualSampler_law (k : ℕ) (bags : Fin (n+2) → Finset (Fin m)) (rank : Fin m → ℕ)
(parent : Fin m → Option (Fin m)) (hb : RankedBags bags rank parent)
(hne : ∀ x,(bags x).Nonempty) (hp : ∀ l p,parent l=some p → rank p<rank l)
(a : Fin (n+2)) (c : PositivePartner bags rank parent a) :
imageLaw (residualSampler k bags rank parent hb hne hp a c)=
push (imageLaw (sampleUnit k n (remainingBags bags a c.val) rank parent
(remainingRanked bags rank parent hb a c.val) (remainingNonempty bags hne a c.val) hp
(remainingPositive bags rank parent hb hne hp a c))) (assembleEdge bags a c.val) := by
exact imageLaw_comp _ _
theorem sampleUnit_tv (k n : ℕ) (bags : Fin n → Finset (Fin m)) (rank : Fin m → ℕ)
(parent : Fin m → Option (Fin m)) (hb : RankedBags bags rank parent)
(hne : ∀ x,(bags x).Nonempty) (hp : ∀ l p,parent l=some p → rank p<rank l)
(hz : 0<count bags parent (plan rank)) :
tv (imageLaw (sampleUnit k n bags rank parent hb hne hp hz))
(uniform (ColoredPairing bags)) ≤ 2*(n:ℝ)^2*m/(2:ℝ)^k := by
induction n using Nat.twoStepInduction with
| zero =>
let : Subsingleton (ColoredPairing bags) := ⟨fun p q=>ColoredPairing.ext
(Pairing.ext (fun x=>Fin.elim0 x)) (funext (fun x=>Fin.elim0 x))⟩
rw [imageLaw_subsingleton,tv_self]
simp
| one =>
rw [singleton_count_zero bags rank parent hb hne hp] at hz
omega
| more n ih _ =>
let a : Fin (n+2) := Fin.last (n+1)
let p := imageLaw (drawEdge bags rank parent hb hne hp a hz k)
let q : PositivePartner bags rank parent a → ℝ := fun c=>
(branchCount bags rank parent a c.val.val.1:ℝ)/count bags parent (plan rank)
let u : PositivePartner bags rank parent a → ColoredPairing bags → ℝ := fun c=>
imageLaw (residualSampler k bags rank parent hb hne hp a c)
let v : PositivePartner bags rank parent a → ColoredPairing bags → ℝ := fun c=>
push (uniform (ColoredPairing (remainingBags bags a c.val))) (assembleEdge bags a c.val)
have hvn (c : PositivePartner bags rank parent a) (y : ColoredPairing bags) : 0 ≤ v c y :=
push_nonneg _ uniform_nonneg _ _
have hvs (c : PositivePartner bags rank parent a) : ∑ y,v c y=1 := by
let : Nonempty (ColoredPairing (remainingBags bags a c.val)) :=
Fintype.card_pos_iff.mp (by rw [remainingCard bags rank parent hb hne hp]; exact c.property)
exact push_sum _ uniform_sum _
have huv (c : PositivePartner bags rank parent a) : tv (u c) (v c) ≤ 2*(n:ℝ)^2*m/(2:ℝ)^k := by
dsimp only [u,v]
rw [residualSampler_law]
exact (push_contraction _ _ _).trans (ih (remainingBags bags a c.val)
(remainingRanked bags rank parent hb a c.val) (remainingNonempty bags hne a c.val)
(remainingPositive bags rank parent hb hne hp a c))
have hpv := bind_perturbation p u v (imageLaw_nonneg _) (imageLaw_sum _)
(2*(n:ℝ)^2*m/(2:ℝ)^k) huv
have hpq := bind_contraction p q v hvn hvs
have hd := drawEdge_positive_tv bags rank parent hb hne hp a hz k
rw [sampleUnit_step_law,←exact_unit_step bags rank parent hb hne hp a hz]
change tv (bind p u) (bind q v)≤_
calc
_ ≤ tv (bind p u) (bind p v)+tv (bind p v) (bind q v) := tv_triangle _ _ _
_ ≤ (2*(n:ℝ)^2*m/(2:ℝ)^k)+(2*((n:ℝ)+2)*m/(2:ℝ)^k) := by
apply add_le_add hpv
exact hpq.trans (by simpa only [Nat.cast_add,Nat.cast_ofNat] using hd)
_ ≤ _ := by
rw [←add_div]
push_cast
apply div_le_div_of_nonneg_right _ (by positivity)
nlinarith [show (0:ℝ)≤n*m by positivity]
end MatchingFPRAS.UnitRefresh.Materialized
namespace MatchingFPRAS.UnitRefresh.Computable
open Finset MatchingFPRAS.Transport
variable {V L : Type*} [Fintype V] [Fintype L] [DecidableEq V] [DecidableEq L]
variable {bags : V → Finset L}
instance edgeDec (e : BagEdge bags) (x : V) : Decidable (e.Incident x) :=
inferInstanceAs (Decidable (x∈e.val.val.1))
instance allowedDec (e : ColoredEdge V L) : Decidable (Allowed bags e) :=
inferInstanceAs (Decidable (∀ x,x∈e.val.1 → e.val.2∈bags x))
def edge (M : PM (BagEdge.Incident (bags := bags))) (x : V) : BagEdge bags :=
M.val.choose (fun e=>e.Incident x) (M.property.2 x (mem_univ x))
omit [Fintype L] [DecidableEq L] in
lemma edge_spec [DecidableEq L] (M : PM (BagEdge.Incident (bags := bags))) (x : V) :
edge M x∈M.val ∧ (edge M x).Incident x :=
M.val.choose_spec _ (M.property.2 x (mem_univ x))
lemma edge_eq (M : PM (BagEdge.Incident (bags := bags))) (x : V) : edge M x=chosenEdge M x :=
chosenEdge_unique M x _ (edge_spec M x).1 (edge_spec M x).2
def mate (M : PM (BagEdge.Incident (bags := bags))) (x : V) : V :=
Sym2.Mem.other' (edge_spec M x).2
lemma mate_eq (M : PM (BagEdge.Incident (bags := bags))) (x : V) : mate M x=chosenMate M x := by
have hp : s(x,mate M x)=(edge M x).val.val.1 := Sym2.other_spec' (edge_spec M x).2
apply (Sym2.congr_right (a:=x)).mp
exact hp.trans (by rw [edge_eq,←chosenMate_pair])
def fromMatching (M : PM (BagEdge.Incident (bags := bags))) : ColoredPairing bags where
pair := ⟨mate M,(fun x=>by simpa only [mate_eq] using chosenMate_involutive M x),
fun x=>by simpa only [mate_eq] using chosenMate_ne M x⟩
color x := (edge M x).val.color
allowed x := (edge M x).property x (edge_spec M x).2
same_color x := by
simp only [mate_eq,edge_eq]
exact congrArg (fun e : BagEdge bags=>e.val.color) (chosenEdge_chosenMate M x)
lemma from_eq (M : PM (BagEdge.Incident (bags := bags))) : fromMatching M=fromPM M := by
apply ColoredPairing.ext
· apply Pairing.ext; intro x; exact mate_eq M x
· funext x; exact congrArg (fun e : BagEdge bags=>e.val.color) (edge_eq M x)
def toMatching (p : ColoredPairing bags) : PM (BagEdge.Incident (bags := bags)) :=
⟨Finset.univ.image p.edgeAt,by exact p.toPM.property⟩
omit [Fintype L] in
lemma to_eq [Fintype L] (p : ColoredPairing bags) : toMatching p=p.toPM := rfl
def pairingEquiv : PM (BagEdge.Incident (bags := bags)) ≃ ColoredPairing bags where
toFun := fromMatching
invFun := toMatching
left_inv M := by
rw [from_eq,to_eq]
exact (coloredPMEquiv (bags:=bags)).left_inv M
right_inv p := by
rw [to_eq,from_eq]
exact (coloredPMEquiv (bags:=bags)).right_inv p
end MatchingFPRAS.UnitRefresh.Computable
namespace MatchingFPRAS.UnitRefresh
open Finset MatchingFPRAS.Variation
def orderedEnum (α : Type*) [Fintype α] [LinearOrder α] : Fin (Fintype.card α) ≃ α :=
((univ : Finset α).orderIsoOfFin (card_univ)).toEquiv.trans
(Equiv.subtypeUnivEquiv (fun _=>mem_univ _))
variable {V L J : Type*} [Fintype V] [DecidableEq V] [Fintype L] [Fintype J] [DecidableEq L] [DecidableEq J]
def ColoredPairing.colorEquiv (bags : V → Finset L) (e : L ≃ J) :
ColoredPairing bags ≃ ColoredPairing (fun x=>(bags x).map e.toEmbedding) where
toFun p := {
pair:=p.pair
color:=fun x=>e (p.color x)
allowed:=fun x=>by simpa using p.allowed x
same_color:=fun x=>congrArg e (p.same_color x) }
invFun p := {
pair:=p.pair
color:=fun x=>e.symm (p.color x)
allowed:=fun x=>by
obtain ⟨l,hl,he⟩:=mem_map.mp (p.allowed x)
simpa only [←he,Equiv.toEmbedding_apply,Equiv.symm_apply_apply] using hl
same_color:=fun x=>congrArg e.symm (p.same_color x) }
left_inv p := by
apply ColoredPairing.ext
· rfl
· funext x; exact e.symm_apply_apply _
right_inv p := by
apply ColoredPairing.ext
· rfl
· funext x; exact e.apply_symm_apply _
open Finset MatchingFPRAS.Variation
variable {V L : Type*} [Fintype V] [LinearOrder V] [Fintype L] [LinearOrder L]
def numberedBags (bags : V → Finset L) : Fin (Fintype.card V) → Finset (Fin (Fintype.card L)) :=
fun x=>(bags (orderedEnum V x)).map (orderedEnum L).symm.toEmbedding
lemma mem_numberedBags (bags : V → Finset L) (x : Fin (Fintype.card V)) (l : Fin (Fintype.card L)) :
l∈numberedBags bags x ↔ orderedEnum L l∈bags (orderedEnum V x) := by
simp [numberedBags]
def numberedRank (rank : L → ℕ) : Fin (Fintype.card L) → ℕ := fun l=>rank (orderedEnum L l)
def numberedParent (parent : L → Option L) : Fin (Fintype.card L) → Option (Fin (Fintype.card L)) :=
fun l=>(parent (orderedEnum L l)).map (orderedEnum L).symm
lemma numberedParent_iff (parent : L → Option L) (l p : Fin (Fintype.card L)) :
numberedParent parent l=some p ↔ parent (orderedEnum L l)=some (orderedEnum L p) := by
simp [numberedParent,Equiv.symm_apply_eq]
lemma numberedRanked (bags : V → Finset L) (rank : L → ℕ) (parent : L → Option L)
(hb : RankedBags bags rank parent) :
RankedBags (numberedBags bags) (numberedRank rank) (numberedParent parent) := by
intro x a ha b hb' hab
rcases hb (orderedEnum V x) (orderedEnum L a) ((mem_numberedBags bags x a).mp ha)
(orderedEnum L b) ((mem_numberedBags bags x b).mp hb')
(fun h=>hab ((orderedEnum L).injective h)) with ⟨hlt,hp⟩|⟨hlt,hp⟩
· exact Or.inl ⟨hlt,(numberedParent_iff parent b a).mpr hp⟩
· exact Or.inr ⟨hlt,(numberedParent_iff parent a b).mpr hp⟩
lemma numberedNonempty (bags : V → Finset L) (hne : ∀ x,(bags x).Nonempty) :
∀ x,(numberedBags bags x).Nonempty := fun x=>(hne (orderedEnum V x)).map
lemma numberedDecreasing (rank : L → ℕ) (parent : L → Option L)
(hp : ∀ l p,parent l=some p → rank p<rank l) :
∀ l p,numberedParent parent l=some p → numberedRank rank p<numberedRank rank l := by
intro l p h; exact hp _ _ ((numberedParent_iff parent l p).mp h)
def numberingEquiv (bags : V → Finset L) :
ColoredPairing (numberedBags bags) ≃ ColoredPairing bags :=
(ColoredPairing.colorEquiv (fun x=>bags (orderedEnum V x)) (orderedEnum L).symm).symm.trans
(ColoredPairing.equiv bags (orderedEnum V))
lemma numbered_count_pos (bags : V → Finset L) (rank : L → ℕ) (parent : L → Option L)
(hb : RankedBags bags rank parent) (hne : ∀ x,(bags x).Nonempty)
(hp : ∀ l p,parent l=some p → rank p<rank l) (M : ColoredPairing bags) :
0<Materialized.count (numberedBags bags) (numberedParent parent)
(Materialized.plan (numberedRank rank)) := by
rw [Materialized.computable_count_eq _ _ _ (numberedRanked bags rank parent hb)
(numberedNonempty bags hne) (numberedDecreasing rank parent hp)]
exact Fintype.card_pos_iff.mpr ⟨(numberingEquiv bags).symm M⟩
def sampleNumbered (k : ℕ) (bags : V → Finset L) (rank : L → ℕ) (parent : L → Option L)
(hb : RankedBags bags rank parent) (hne : ∀ x,(bags x).Nonempty)
(hp : ∀ l p,parent l=some p → rank p<rank l) (M : ColoredPairing bags)
(bits : Fin (Fintype.card V) → Fin k → Bool) : ColoredPairing bags :=
numberingEquiv bags (Materialized.sampleUnit k (Fintype.card V) (numberedBags bags)
(numberedRank rank) (numberedParent parent) (numberedRanked bags rank parent hb)
(numberedNonempty bags hne) (numberedDecreasing rank parent hp)
(numbered_count_pos bags rank parent hb hne hp M) bits)
theorem sampleNumbered_tv (k : ℕ) (bags : V → Finset L) (rank : L → ℕ) (parent : L → Option L)
(hb : RankedBags bags rank parent) (hne : ∀ x,(bags x).Nonempty)
(hp : ∀ l p,parent l=some p → rank p<rank l) (M : ColoredPairing bags) :
tv (imageLaw (sampleNumbered k bags rank parent hb hne hp M))
(uniform (ColoredPairing bags)) ≤ 2*(Fintype.card V:ℝ)^2*Fintype.card L/(2:ℝ)^k := by
have ht:=Materialized.sampleUnit_tv k (Fintype.card V) (numberedBags bags)
(numberedRank rank) (numberedParent parent) (numberedRanked bags rank parent hb)
(numberedNonempty bags hne) (numberedDecreasing rank parent hp)
(numbered_count_pos bags rank parent hb hne hp M)
change tv (imageLaw (numberingEquiv bags ∘ _)) _ ≤ _
rw [imageLaw_comp,←imageLaw_equiv (numberingEquiv bags)]
exact (push_contraction _ _ _).trans ht
open MatchingFPRAS.Transport
def sampleMatching (k : ℕ) (bags : V → Finset L) (rank : L → ℕ) (parent : L → Option L)
(hb : RankedBags bags rank parent) (hne : ∀ x,(bags x).Nonempty)
(hp : ∀ l p,parent l=some p → rank p<rank l)
(M : PM (BagEdge.Incident (bags:=bags)))
(bits : Fin (Fintype.card V) → Fin k → Bool) : PM (BagEdge.Incident (bags:=bags)) :=
(Computable.pairingEquiv (bags:=bags)).symm
(sampleNumbered k bags rank parent hb hne hp (Computable.pairingEquiv M) bits)
theorem sampleMatching_tv (k : ℕ) (bags : V → Finset L) (rank : L → ℕ) (parent : L → Option L)
(hb : RankedBags bags rank parent) (hne : ∀ x,(bags x).Nonempty)
(hp : ∀ l p,parent l=some p → rank p<rank l)
(M : PM (BagEdge.Incident (bags:=bags))) :
tv (imageLaw (sampleMatching k bags rank parent hb hne hp M))
(uniform (PM (BagEdge.Incident (bags:=bags)))) ≤
2*(Fintype.card V:ℝ)^2*Fintype.card L/(2:ℝ)^k := by
have ht:=sampleNumbered_tv k bags rank parent hb hne hp (Computable.pairingEquiv M)
change tv (imageLaw ((Computable.pairingEquiv (bags:=bags)).symm ∘ _)) _ ≤ _
rw [imageLaw_comp,←imageLaw_equiv (Computable.pairingEquiv (bags:=bags)).symm]
exact (push_contraction _ _ _).trans ht
end MatchingFPRAS.UnitRefresh
end OAI