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Add lean source and binary files (part 47)
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import Mathlib
import OAI.Combinatorics.MatchingCount.Sampling.RankOrder
namespace OAI
namespace MatchingFPRAS.UnitRefresh.Materialized
open Finset
variable {V : Type*} [Fintype V] [DecidableEq V]
def plan {m : ℕ} (rank : Fin m → ℕ) : List (Fin m) :=
(List.ofFn (fun l : Fin m => l)).mergeSort (fun a b=>decide (rank b≤rank a))
lemma plan_mem {m : ℕ} (rank : Fin m → ℕ) (a : Fin m) : a∈plan rank := by
unfold plan
rw [(List.mergeSort_perm _ _).mem_iff]
simp
lemma plan_length {m : ℕ} (rank : Fin m → ℕ) : (plan rank).length=m := by
unfold plan
rw [(List.mergeSort_perm _ _).length_eq]
simp
lemma plan_sorted {m : ℕ} (rank : Fin m → ℕ) :
(plan rank).Pairwise (fun a b=>rank b≤rank a) := by
let r := fun a b : Fin m => rank b≤rank a
let : Std.Total r := ⟨fun a b => le_total (rank b) (rank a)⟩
let : IsTrans (Fin m) r := ⟨fun a b c hab hbc => hbc.trans hab⟩
exact List.pairwise_mergeSort' r _
lemma plan_legal {m : ℕ} (bags : V → 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) :
LegalPlan bags parent (plan rank) univ := by
apply rank_order_legal bags rank parent hb hp _ (plan_sorted rank)
· intro x _; exact hne x
· intro x _ a _; exact plan_mem rank a
theorem computable_count_eq {m : ℕ} (bags : V → 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) :
count bags parent (plan rank)=Fintype.card (ColoredPairing bags) := by
rw [coloredPairing_card]
change count bags parent (plan rank)=assignmentPartition bags (fun _=>pairingCount)
rw [←active_univ]
rw [tableDP_correct bags parent _ _ (plan_legal bags rank parent hb hne hp)]
unfold count
apply prod_congr rfl
intro a _
rw [read_run]
apply finiteDP_correct
intro b r hr
rw [plan_length] at hr
simp [initial,read_tabulate,hr]
def branchCount {m : ℕ} (bags : V → Finset (Fin m)) (rank : Fin m → ℕ)
(parent : Fin m → Option (Fin m)) (a b : V) : ℕ :=
count (residualBags bags a b) parent (plan rank)
lemma branchCount_eq {m : ℕ} (bags : V → 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 b : V) : branchCount bags rank parent a b=
Fintype.card (ColoredPairing (residualBags bags a b)) := by
apply computable_count_eq
· intro x c hc d hd; exact hb x.val c hc d hd
· intro x; exact hne x.val
· exact hp
lemma branchCount_sum {m : ℕ} (bags : V → 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 : V) : (∑ c : Partner bags a,branchCount bags rank parent a c.val.1)=
count bags parent (plan rank) := by
rw [computable_count_eq bags rank parent hb hne hp,
Fintype.card_congr (ColoredPairing.split a),Fintype.card_sigma]
apply sum_congr rfl
intro c _
exact branchCount_eq bags rank parent hb hne hp a c.val.1
open Finset MatchingFPRAS.FiniteChoice
variable {n m : ℕ}
def validBranch (bags : Fin n → Finset (Fin m)) (a : Fin n) (bc : Fin n × Fin m) : Prop :=
bc.1≠a ∧ bc.2∈bags a ∧ bc.2∈bags bc.1
instance (bags : Fin n → Finset (Fin m)) (a : Fin n) (bc : Fin n × Fin m) :
Decidable (validBranch bags a bc) := inferInstanceAs (Decidable (_ ∧ _ ∧ _))
def edgeCount (bags : Fin n → Finset (Fin m)) (rank : Fin m → ℕ)
(parent : Fin m → Option (Fin m)) (a : Fin n) (bc : Fin n × Fin m) : ℕ :=
if validBranch bags a bc then branchCount bags rank parent a bc.1 else 0
lemma edgeCount_sum (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)
(a : Fin n) : (∑ bc,edgeCount bags rank parent a bc)=count bags parent (plan rank) := by
rw [←branchCount_sum bags rank parent hb hne hp a]
change (∑ bc,if validBranch bags a bc then branchCount bags rank parent a bc.1 else 0)=_
rw [←Finset.sum_filter]
exact Finset.sum_subtype _ (by intro bc; simp only [Finset.mem_filter,Finset.mem_univ,true_and]; rfl) _
def edgeProbability (bags : Fin n → Finset (Fin m)) (rank : Fin m → ℕ)
(parent : Fin m → Option (Fin m)) (a : Fin n) (i : Fin (n*m)) : ℚ :=
edgeCount bags rank parent a (finProdFinEquiv.symm i)/count bags parent (plan rank)
lemma edgeProbability_nonneg (bags : Fin n → Finset (Fin m)) (rank : Fin m → ℕ)
(parent : Fin m → Option (Fin m)) (a : Fin n) (i : Fin (n*m)) :
0≤edgeProbability bags rank parent a i := by unfold edgeProbability; positivity
lemma edgeProbability_sum (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)
(a : Fin n) (hz : 0<count bags parent (plan rank)) :
∑ i,edgeProbability bags rank parent a i=1 := by
unfold edgeProbability
rw [←Finset.sum_div,←Nat.cast_sum]
rw [←finProdFinEquiv.sum_comp (fun i=>edgeCount bags rank parent a (finProdFinEquiv.symm i))]
simp only [Equiv.symm_apply_apply]
rw [edgeCount_sum bags rank parent hb hne hp a]
exact div_self (by exact_mod_cast hz.ne')
def drawEdge (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)
(a : Fin n) (hz : 0<count bags parent (plan rank)) (k : ℕ) (bits : Fin k → Bool) :
{c : Partner bags a // 0<branchCount bags rank parent a c.val.1} := by
let p := edgeProbability bags rank parent a
have hs := edgeProbability_sum bags rank parent hb hne hp a hz
let i := chooseBits p hs k bits
let bc := finProdFinEquiv.symm i
have hh : 0<edgeCount bags rank parent a bc := by
have h := chooseBits_pos p hs k bits
change 0<(edgeCount bags rank parent a bc:ℚ)/(count bags parent (plan rank):ℚ) at h
have := (div_pos_iff_of_pos_right (by exact_mod_cast hz : (0:ℚ)<count bags parent (plan rank))).mp h
exact_mod_cast this
have hv : validBranch bags a bc := by
by_contra hv
simp [edgeCount,hv] at hh
exact ⟨⟨bc,hv⟩,by simpa [edgeCount,hv] using hh⟩
theorem drawEdge_tv (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)
(a : Fin n) (hz : 0<count bags parent (plan rank)) (k : ℕ) :
let p := edgeProbability bags rank parent a
let hs := edgeProbability_sum bags rank parent hb hne hp a hz
(∑ i,|tapeLaw p hs k i-p i|)/2≤2*(n*m)/(2:ℚ)^k := by
dsimp only
rw [tapeLaw_eq]
simpa only [Nat.cast_mul] using fixed_bit_choice _ (edgeProbability_nonneg bags rank parent a) _ k
end MatchingFPRAS.UnitRefresh.Materialized
namespace MatchingFPRAS.UnitRefresh
open Finset
variable {U V L : Type*} [Fintype U] [Fintype V] [Fintype L] [DecidableEq U] [DecidableEq V] [DecidableEq L]
def ColoredPairing.map (bags : V → Finset L) (e : U ≃ V)
(p : ColoredPairing (fun x=>bags (e x))) : ColoredPairing bags where
pair := p.pair.map e
color x := p.color (e.symm x)
allowed x := by simpa using p.allowed (e.symm x)
same_color x := by simpa [Pairing.map] using p.same_color (e.symm x)
def ColoredPairing.comap (bags : V → Finset L) (e : U ≃ V)
(p : ColoredPairing bags) : ColoredPairing (fun x=>bags (e x)) where
pair := p.pair.map e.symm
color x := p.color (e x)
allowed x := p.allowed (e x)
same_color x := by simpa [Pairing.map] using p.same_color (e x)
def ColoredPairing.equiv (bags : V → Finset L) (e : U ≃ V) :
ColoredPairing (fun x=>bags (e x)) ≃ ColoredPairing bags where
toFun := ColoredPairing.map bags e
invFun := ColoredPairing.comap bags e
left_inv p := by
apply ColoredPairing.ext
· ext x; simp [ColoredPairing.map,ColoredPairing.comap,Pairing.map]
· funext x; simp [ColoredPairing.map,ColoredPairing.comap]
right_inv p := by
apply ColoredPairing.ext
· ext x; simp [ColoredPairing.map,ColoredPairing.comap,Pairing.map]
· funext x; simp [ColoredPairing.map,ColoredPairing.comap]
def gapEquiv {n : ℕ} (a : Fin (n+1)) : Fin n ≃ {x : Fin (n+1) // x≠a} :=
Equiv.optionSubtype a ⟨(finSuccEquiv' a).symm,rfl⟩
def removePairEquiv {n : ℕ} (a b : Fin (n+2)) (hb : b≠a) :
Fin n ≃ withoutPair a b := by
let e := gapEquiv a
let b' := e.symm ⟨b,hb⟩
let f := gapEquiv b'
refine {
toFun := fun i=>⟨(e (f i).val).val,(e (f i).val).property,?_⟩
invFun := fun x=>f.symm ⟨e.symm ⟨x.val,x.property.1⟩,?_⟩
left_inv := ?_
right_inv := ?_ }
· intro h
apply (f i).property
apply e.injective
apply Subtype.ext
simpa [b'] using h
· intro h
have hh := congrArg (fun i=>(e i).val) h
apply x.property.2
simpa [b'] using hh
· intro i
apply f.injective
simp
· intro x
apply Subtype.ext
simp
end MatchingFPRAS.UnitRefresh
namespace MatchingFPRAS.UnitRefresh.Materialized
open Finset MatchingFPRAS.FiniteChoice
variable {m : ℕ}
lemma singleton_count_zero (bags : Fin 1 → 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) :
count bags parent (plan rank)=0 := by
rw [computable_count_eq bags rank parent hb hne hp]
have : IsEmpty (ColoredPairing bags) := ⟨fun p=>p.pair.no_fixed 0 (Subsingleton.elim _ _)⟩
exact Fintype.card_eq_zero
def sampleUnit (k : ℕ) : (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) →
0<count bags parent (plan rank) → (Fin n → Fin k → Bool) → ColoredPairing bags
| 0,bags,_,_,_,_,_,_,_ =>
⟨⟨fun x=>Fin.elim0 x,fun x=>Fin.elim0 x,fun x=>Fin.elim0 x⟩,
(fun x=>Fin.elim0 x),(fun x=>Fin.elim0 x),(fun x=>Fin.elim0 x)⟩
| 1,bags,rank,parent,hb,hne,hp,hz,_ =>
False.elim (by rw [singleton_count_zero bags rank parent hb hne hp] at hz; omega)
| n+2,bags,rank,parent,hb,hne,hp,hz,bits => by
let a : Fin (n+2) := Fin.last (n+1)
let c := drawEdge bags rank parent hb hne hp a hz k (bits a)
let e := removePairEquiv a c.val.val.1 c.val.property.1
let b' : Fin n → Finset (Fin m) := fun x=>bags (e x).val
have hb' : RankedBags b' rank parent := by
intro x l hl r hr; exact hb (e x).val l hl r hr
have hne' : ∀ x,(b' x).Nonempty := fun x=>hne (e x).val
have hz' : 0<count b' parent (plan rank) := by
rw [computable_count_eq b' rank parent hb' hne' hp]
rw [Fintype.card_congr (ColoredPairing.equiv (residualBags bags a c.val.val.1) e)]
rw [←branchCount_eq bags rank parent hb hne hp]
exact c.property
let p := sampleUnit k n b' rank parent hb' hne' hp hz'
(fun i=>bits i.castSucc.castSucc)
exact (ColoredPairing.map (residualBags bags a c.val.val.1) e p).insert a c.val
open Finset MatchingFPRAS.FiniteChoice MatchingFPRAS.Variation
open scoped Classical
variable {n m : ℕ}
abbrev PositivePartner (bags : Fin n → Finset (Fin m)) (rank : Fin m → ℕ)
(parent : Fin m → Option (Fin m)) (a : Fin n) :=
{c : Partner bags a // 0<branchCount bags rank parent a c.val.1}
def partnerIndex (bags : Fin n → Finset (Fin m)) (rank : Fin m → ℕ)
(parent : Fin m → Option (Fin m)) (a : Fin n)
(c : PositivePartner bags rank parent a) : Fin (n*m) := finProdFinEquiv c.val.val
lemma partnerIndex_injective (bags : Fin n → Finset (Fin m)) (rank : Fin m → ℕ)
(parent : Fin m → Option (Fin m)) (a : Fin n) :
Function.Injective (partnerIndex bags rank parent a) := by
intro c d h
apply Subtype.ext
apply Subtype.ext
exact finProdFinEquiv.injective h
lemma drawEdge_index (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)
(a : Fin n) (hz : 0<count bags parent (plan rank)) (k : ℕ) (bits : Fin k → Bool) :
partnerIndex bags rank parent a (drawEdge bags rank parent hb hne hp a hz k bits)=
chooseBits (edgeProbability bags rank parent a) (edgeProbability_sum bags rank parent hb hne hp a hz) k bits := by
exact finProdFinEquiv.apply_symm_apply _
lemma drawEdge_law (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)
(a : Fin n) (hz : 0<count bags parent (plan rank)) (k : ℕ)
(c : PositivePartner bags rank parent a) :
imageLaw (drawEdge bags rank parent hb hne hp a hz k) c=
(tapeLaw (edgeProbability bags rank parent a) (edgeProbability_sum bags rank parent hb hne hp a hz) k
(partnerIndex bags rank parent a c):ℝ) := by
rw [imageLaw_eq_count]
simp only [tapeLaw,Rat.cast_div,Rat.cast_natCast,Rat.cast_pow,Rat.cast_ofNat,
Fintype.card_fun,Fintype.card_fin,Fintype.card_bool,Nat.cast_pow,Nat.cast_ofNat]
congr 2
apply congrArg Finset.card
ext bits
simp only [mem_filter,mem_univ,true_and]
rw [←drawEdge_index]
exact (partnerIndex_injective bags rank parent a).eq_iff.symm
theorem drawEdge_positive_tv (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)
(a : Fin n) (hz : 0<count bags parent (plan rank)) (k : ℕ) :
tv (imageLaw (drawEdge bags rank parent hb hne hp a hz k))
(fun c : PositivePartner bags rank parent a=>(branchCount bags rank parent a c.val.val.1:ℝ)/count bags parent (plan rank))
≤ 2*n*m/(2:ℝ)^k := by
let idx := partnerIndex bags rank parent a
let p := edgeProbability bags rank parent a
let hs := edgeProbability_sum bags rank parent hb hne hp a hz
have he (c : PositivePartner bags rank parent a) :
(p (idx c):ℝ)=(branchCount bags rank parent a c.val.val.1:ℝ)/count bags parent (plan rank) := by
have hv : validBranch bags a c.val.val := c.val.property
simp [p,idx,partnerIndex,edgeProbability,edgeCount,hv]
have hg : ∑ c : PositivePartner bags rank parent a,|(tapeLaw p hs k (idx c):ℝ)-(p (idx c):ℝ)| ≤
∑ i : Fin (n*m),|(tapeLaw p hs k i:ℝ)-(p i:ℝ)| := by
change (∑ c,|(tapeLaw p hs k (partnerIndex bags rank parent a c):ℝ)-(p (partnerIndex bags rank parent a c):ℝ)|)≤_
rw [←Finset.sum_image (s:=univ) (f:=fun i=>|(tapeLaw p hs k i:ℝ)-(p i:ℝ)|)
(fun c _ d _ h=>(partnerIndex_injective bags rank parent a) h)]
exact Finset.sum_le_univ_sum_of_nonneg (fun _=>abs_nonneg _)
have ht : (∑ i : Fin (n*m),|(tapeLaw p hs k i:ℝ)-(p i:ℝ)|)/2 ≤ 2*(n*m)/(2:ℝ)^k := by
have hh := drawEdge_tv bags rank parent hb hne hp a hz k
have hcast := (Rat.cast_le (K:=ℝ)).mpr hh
push_cast at hcast
simpa only [p,hs,Nat.cast_mul] using hcast
unfold tv
have hg' : (∑ c : PositivePartner bags rank parent a,
|imageLaw (drawEdge bags rank parent hb hne hp a hz k) c-
(branchCount bags rank parent a c.val.val.1:ℝ)/count bags parent (plan rank)|)≤
∑ i : Fin (n*m),|(tapeLaw p hs k i:ℝ)-(p i:ℝ)| := by
simpa only [drawEdge_law,he] using hg
exact (div_le_div_of_nonneg_right hg' (by norm_num)).trans (by simpa only [mul_assoc] using ht)
noncomputable def positiveSplitEquiv (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)
(a : Fin n) :
(Σ c : PositivePartner bags rank parent a,ColoredPairing (residualBags bags a c.val.val.1)) ≃ ColoredPairing bags := by
let e : (Σ c : PositivePartner bags rank parent a,ColoredPairing (residualBags bags a c.val.val.1)) ≃
(Σ c : Partner bags a,ColoredPairing (residualBags bags a c.val.1)) := {
toFun := fun s=>⟨s.1.val,s.2⟩
invFun := fun s=>⟨⟨s.1,by
rw [branchCount_eq bags rank parent hb hne hp]
exact Fintype.card_pos_iff.mpr ⟨s.2⟩⟩,s.2⟩
left_inv := fun s=>by rcases s with ⟨⟨c,hc⟩,x⟩; rfl
right_inv := fun s=>by cases s; rfl }
exact e.trans (ColoredPairing.split a).symm
lemma positiveSplitEquiv_apply (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)
(a : Fin n) (c : PositivePartner bags rank parent a)
(x : ColoredPairing (residualBags bags a c.val.val.1)) :
positiveSplitEquiv bags rank parent hb hne hp a ⟨c,x⟩=x.insert a c.val := rfl
theorem unit_self_reduction_law (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)
(a : Fin n) (hz : 0<count bags parent (plan rank)) (z : ColoredPairing bags) :
push (sigmaLift
(fun c : PositivePartner bags rank parent a=>(branchCount bags rank parent a c.val.val.1:ℝ)/count bags parent (plan rank))
(fun c=>uniform (ColoredPairing (residualBags bags a c.val.val.1))))
(positiveSplitEquiv bags rank parent hb hne hp a) z=uniform (ColoredPairing bags) z := by
let : Nonempty (ColoredPairing bags) := Fintype.card_pos_iff.mp (by
rwa [←computable_count_eq bags rank parent hb hne hp])
simp_rw [branchCount_eq bags rank parent hb hne hp,computable_count_eq bags rank parent hb hne hp]
exact uniform_sigma (positiveSplitEquiv bags rank parent hb hne hp a) z
end MatchingFPRAS.UnitRefresh.Materialized
end OAI