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Add lean source and binary files (part 62)
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import Mathlib.Data.Fin.Embedding
import Mathlib.Tactic.Linarith
import OAI.Computability.PerfectCompleteness.Machines.EncodingLemmas
import OAI.Computability.PerfectCompleteness.Reduction.CanonicalGameLemmas
namespace OAI
namespace PerfectCompleteness.CompletionOutput
open scoped BigOperators Classical
open UniqueGamesTheorem.Foundations.Games
open WeightRounding CompletionSoundness CompletionRounding
open CompletionSoundness.LegalProjectionGame
noncomputable section
variable {m l r q : Nat} {L : Fin l → Type*} {R : Fin r → Type*}
[∀ x, Fintype (L x)]
(G : LegalProjectionGame (Fin m) (Fin l) (Fin r) L R)
(legalL : ∀ x, L x ↪ Fin (2 * q)) (legalR : ∀ y, R y ↪ Fin q)
(hsmall : ∀ e b, Fintype.card {a : L (G.left e) // G.projection e a = b} ≤ 2)
def family : G.CompletionFamily legalL legalR :=
Classical.choose (G.exists_completionFamily_bounded legalL legalR hsmall (by simp))
theorem family_size (e : Fin m) :
(family G legalL legalR hsmall).size e ≤
max 1 (2 * q - Fintype.card (L (G.left e))) := by
simpa only [family, Fintype.card_fin] using
Classical.choose_spec
(G.exists_completionFamily_bounded legalL legalR hsmall (by simp)) e
theorem family_total_size (hq : 0 < q) :
(∑ e, (family G legalL legalR hsmall).size e) ≤ m * (2 * q) := by
calc
_ ≤ ∑ _e : Fin m, 2 * q := by
apply Finset.sum_le_sum
intro e _
exact (family_size G legalL legalR hsmall e).trans
(max_le (by omega) (Nat.sub_le _ _))
_ = m * (2 * q) := by simp
def construct (w : PositiveWeights m) (δ : ℚ) (hδ : 0 < δ) : Instance q :=
CompletionRounding.output w (family G legalL legalR hsmall) δ hδ
@[simp] theorem construct_leftVertices (w : PositiveWeights m) (δ : ℚ) (hδ : 0 < δ) :
(construct G legalL legalR hsmall w δ hδ).leftVertices = l := rfl
@[simp] theorem construct_rightVertices (w : PositiveWeights m) (δ : ℚ) (hδ : 0 < δ) :
(construct G legalL legalR hsmall w δ hδ).rightVertices = r := rfl
theorem construct_edge_count (w : PositiveWeights m) (δ : ℚ) (hδ : 0 < δ)
(hq : 0 < q) :
(construct G legalL legalR hsmall w δ hδ).edges.length ≤
⌈(3 : ℚ) / δ⌉₊ * m * (2 * q) := by
exact (output_edge_count_le w (family G legalL legalR hsmall) δ hδ).trans
(by simpa only [Nat.mul_assoc] using
Nat.mul_le_mul_left ⌈(3 : ℚ) / δ⌉₊ (family_total_size G legalL legalR hsmall hq))
theorem construct_word_count (w : PositiveWeights m) (δ : ℚ) (hδ : 0 < δ)
(hq : 0 < q) :
(Encoding.gameWords (construct G legalL legalR hsmall w δ hδ)).length ≤
4 + (⌈(3 : ℚ) / δ⌉₊ * m * (2 * q)) * (2 * q + 2) := by
rw [Encoding.gameWords_length]
exact Nat.add_le_add_left
(Nat.mul_le_mul_right (2 * q + 2) (construct_edge_count G legalL legalR hsmall w δ hδ hq)) 4
variable [∀ y, Fintype (R y)] [∀ x, Nonempty (L x)] [∀ y, Nonempty (R y)]
theorem construct_value_le (w : PositiveWeights m)
(hweights : ∀ e, G.occurrences.weight e = (w.weight e : ℝ))
(δ : ℚ) (hδ : 0 < δ) (hq : 0 < q) :
(construct G legalL legalR hsmall w δ hδ).value ≤
G.value + G.occurrences.expectation
(fun e => 2 / (2 * q - Fintype.card (L (G.left e)) : Nat)) + (δ : ℝ) / 3 :=
output_value_le w (family G legalL legalR hsmall) hweights δ hδ hq
theorem construct_value_le_of_residual_bound (w : PositiveWeights m)
(hweights : ∀ e, G.occurrences.weight e = (w.weight e : ℝ))
(δ : ℚ) (hδ : 0 < δ) (hq : 0 < q) (η : ℝ)
(hη : ∀ e, 2 / (2 * q - Fintype.card (L (G.left e)) : Nat) ≤ η) :
(construct G legalL legalR hsmall w δ hδ).value ≤ G.value + η + (δ : ℝ) / 3 :=
output_value_le_of_residual_bound w (family G legalL legalR hsmall) hweights δ hδ hq η hη
theorem construct_perfectlyComplete (w : PositiveWeights m)
(hweights : ∀ e, G.occurrences.weight e = (w.weight e : ℝ))
(δ : ℚ) (hδ : 0 < δ) (hq : 0 < q) (hcomplete : G.value = 1) :
PerfectlyComplete (construct G legalL legalR hsmall w δ hδ) := by
apply ((construct G legalL legalR hsmall w δ hδ).perfectlyComplete_iff_value_eq_one hq).2
exact output_value_eq_one w (family G legalL legalR hsmall) hweights δ hδ hq hcomplete
theorem construct_soundAt (w : PositiveWeights m)
(hweights : ∀ e, G.occurrences.weight e = (w.weight e : ℝ))
(δ : ℚ) (hδ : 0 < δ) (hq : 0 < q) (η : ℝ)
(hη : ∀ e, 2 / (2 * q - Fintype.card (L (G.left e)) : Nat) ≤ η)
(d : RationalThreshold)
(hbudget : G.value + η + (δ : ℝ) / 3 ≤ (d.numerator : ℝ) / d.denominator) :
SoundAt d (construct G legalL legalR hsmall w δ hδ) := by
apply ((construct G legalL legalR hsmall w δ hδ).soundAt_iff_value_le hq d).2
exact (construct_value_le_of_residual_bound G legalL legalR hsmall w hweights
δ hδ hq η hη).trans hbudget
end
end PerfectCompleteness.CompletionOutput
namespace PerfectCompleteness.CompletionParameters
open scoped BigOperators Classical
open UniqueGamesTheorem.Foundations.Games
open WeightRounding CompletionSoundness CompletionOutput
noncomputable section
theorem residual_le_third {q n : Nat} {δ : ℝ} (hq : 0 < q)
(hn : n ≤ q) (hδ : 0 < δ) (hbudget : 6 ≤ δ * q) :
2 / (2 * q - n : Nat) ≤ δ / 3 := by
have hden : q ≤ 2 * q - n := by omega
have hden_real : (q : ℝ) ≤ (2 * q - n : Nat) := by exact_mod_cast hden
have hpos : (0 : ℝ) < (2 * q - n : Nat) := by
exact_mod_cast lt_of_lt_of_le hq hden
rw [div_le_iff₀ hpos]
have hmul := mul_le_mul_of_nonneg_left hden_real (le_of_lt hδ)
nlinarith
def embedFin (T : Type*) [Fintype T] (n : Nat) (h : Fintype.card T ≤ n) : T ↪ Fin n :=
(Fintype.equivFin T).toEmbedding.trans (Fin.castLEEmb h)
section Game
variable {m l r q : Nat} {L : Fin l → Type*} {R : Fin r → Type*}
[∀ x, Fintype (L x)] [∀ y, Fintype (R y)]
[∀ x, Nonempty (L x)] [∀ y, Nonempty (R y)]
(G : LegalProjectionGame (Fin m) (Fin l) (Fin r) L R)
(legalL : ∀ x, L x ↪ Fin (2 * q)) (legalR : ∀ y, R y ↪ Fin q)
(hsmall : ∀ e b, Fintype.card {a : L (G.left e) // G.projection e a = b} ≤ 2)
theorem construct_value_le_delta (w : PositiveWeights m)
(hweights : ∀ e, G.occurrences.weight e = (w.weight e : ℝ))
(δ : ℚ) (hδ : 0 < δ) (hq : 0 < q)
(hleft : ∀ x, Fintype.card (L x) ≤ q)
(hbudget : (6 : ℝ) ≤ (δ : ℝ) * q)
(hsound : G.value ≤ (δ : ℝ) / 3) :
(construct G legalL legalR hsmall w δ hδ).value ≤ (δ : ℝ) := by
have hδreal : (0 : ℝ) < (δ : ℝ) := by exact_mod_cast hδ
have hres : ∀ e, 2 / (2 * q - Fintype.card (L (G.left e)) : Nat) ≤ (δ : ℝ) / 3 :=
fun e => residual_le_third hq (hleft (G.left e)) hδreal hbudget
have h := construct_value_le_of_residual_bound G legalL legalR hsmall
w hweights δ hδ hq ((δ : ℝ) / 3) hres
linarith
theorem construct_soundAt_of_budget (w : PositiveWeights m)
(hweights : ∀ e, G.occurrences.weight e = (w.weight e : ℝ))
(δ : ℚ) (hδ : 0 < δ) (hq : 0 < q)
(hleft : ∀ x, Fintype.card (L x) ≤ q)
(hbudget : (6 : ℝ) ≤ (δ : ℝ) * q)
(hsound : G.value ≤ (δ : ℝ) / 3) (d : RationalThreshold)
(hthreshold : (δ : ℝ) ≤ (d.numerator : ℝ) / d.denominator) :
SoundAt d (construct G legalL legalR hsmall w δ hδ) := by
apply ((construct G legalL legalR hsmall w δ hδ).soundAt_iff_value_le hq d).2
exact (construct_value_le_delta G legalL legalR hsmall w hweights
δ hδ hq hleft hbudget hsound).trans hthreshold
end Game
theorem exists_target {m l r q : Nat} {L : Fin l → Type*} {R : Fin r → Type*}
[∀ x, Fintype (L x)] [∀ y, Fintype (R y)]
[∀ x, Nonempty (L x)] [∀ y, Nonempty (R y)]
(G : LegalProjectionGame (Fin m) (Fin l) (Fin r) L R)
(w : PositiveWeights m)
(hweights : ∀ e, G.occurrences.weight e = (w.weight e : ℝ))
(hsmall : ∀ e b, Fintype.card {a : L (G.left e) // G.projection e a = b} ≤ 2)
(hleft : ∀ x, Fintype.card (L x) ≤ q)
(hright : ∀ y, Fintype.card (R y) ≤ q)
(δ : ℚ) (hδ : 0 < δ) (hq : 0 < q)
(hbudget : (6 : ℝ) ≤ (δ : ℝ) * q) :
∃ target : Instance q,
target.leftVertices = l ∧ target.rightVertices = r ∧
target.edges.length ≤ ⌈(3 : ℚ) / δ⌉₊ * m * (2 * q) ∧
(G.value = 1 → PerfectlyComplete target) ∧
(G.value ≤ (δ : ℝ) / 3 → target.value ≤ (δ : ℝ)) := by
let legalL : ∀ x, L x ↪ Fin (2 * q) :=
fun x => embedFin (L x) (2 * q) ((hleft x).trans (by omega))
let legalR : ∀ y, R y ↪ Fin q := fun y => embedFin (R y) q (hright y)
refine ⟨construct G legalL legalR hsmall w δ hδ, rfl, rfl,
construct_edge_count G legalL legalR hsmall w δ hδ hq, ?_, ?_⟩
· exact construct_perfectlyComplete G legalL legalR hsmall w hweights δ hδ hq
· exact construct_value_le_delta G legalL legalR hsmall w hweights δ hδ hq hleft hbudget
end
end PerfectCompleteness.CompletionParameters
end OAI