File size: 5,186 Bytes
ea76aac
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
import Mathlib
import OAI.Computability.MaxCut.Analysis.CubeEquiv
import OAI.Computability.MaxCut.Estimates.ListSum

namespace OAI

noncomputable section
namespace OptimalMaxCut.RawGrid
open scoped BigOperators
open Finset MaxCutGames.Foundations.Target MaxCutGames.Foundations.Hastad
open LongCode LongCode.InstanceAdapter CounterMachine.Expr
attribute [local instance] Classical.propDecidable

@[simp] theorem vertices_bits {q : ℕ} (g : Instance q) : vertices (bits g) = g.vertices := (word_header g).1
@[simp] theorem edges_bits {q : ℕ} (g : Instance q) : edges (bits g) = g.constraints.length := (word_header g).2.2
@[simp] theorem row_source {q : ℕ} (g : Instance q) (e : Fin g.constraints.length) :
    row q (bits g) e 0 = g.constraints[e].source.val := by
  simpa [row] using InstanceAdapter.row_source g e
@[simp] theorem row_target {q : ℕ} (g : Instance q) (e : Fin g.constraints.length) :
    row q (bits g) e 1 = g.constraints[e].target.val := InstanceAdapter.row_target g e
@[simp] theorem row_image {q : ℕ} (g : Instance q) (e : Fin g.constraints.length) (i : Fin q) :
    row q (bits g) e (2+i.val) = g.constraints[e].permutation.images[i].val := InstanceAdapter.row_image g e i

@[simp] theorem degree_bits {q : ℕ} (g : Instance q) (y : Fin g.vertices) :
    degree q (bits g) y = InstanceAdapter.degree g y := by
  rw [degree, edges_bits, ← Fin.sum_univ_eq_sum_range]
  unfold InstanceAdapter.degree
  apply sum_congr rfl
  intro e he
  rw [row_target]
  simp only [Fin.val_inj]

@[simp] theorem lookup_fin {q : ℕ} (x : Cube (Fin q)) (i : Fin q) :
    lookup x i.val = (finTwoEquiv.symm (x i)).val := by
  simp [lookup, Fin.val_inj]

@[simp] theorem permCode_bits {q : ℕ} (g : Instance q) (e : Fin g.constraints.length)
    (x : Cube (Fin q)) :
    permCode (bits g) e x = (cubeEquiv q (cubePerm (MaxCutGames.Explicit.MachineOutputContract.permutationEquiv g.constraints[e].permutation) x)).val := by
  simp only [permCode, row_image, lookup_fin, cubeEquiv, Equiv.trans_apply, finFunctionFinEquiv_apply]
  rfl

@[simp] theorem query_bits {q : ℕ} (g : Instance q) (e : Fin g.constraints.length)
    (x : Cube (Fin q)) :
    query (bits g) e x = (vertexEquiv g.vertices q
      (g.constraints[e].source,cubePerm (MaxCutGames.Explicit.MachineOutputContract.permutationEquiv g.constraints[e].permutation) x)).val := by
  simp only [query, permCode_bits, row_source]
  rfl

@[simp] theorem gridSize_bits {q : ℕ} (g : Instance q) (K : ℕ) :
    gridSize q K (bits g) = Game.gridSize (Fin g.vertices) (Fin g.constraints.length) q K := by
  simp [gridSize, Game.gridSize, Game.Sample, vertices_bits, edges_bits]

 theorem rational_floor (c : ℚ) (hc : 0 ≤ c) (P d m : ℕ) :
    ⌊(P:ℚ)*((d:ℚ)*c/((m:ℚ)*(d:ℚ)^2))⌋₊ =
      P*d*c.num.toNat/(c.den*m*d^2) := by
  have hn : ((c.num.toNat:ℕ):ℚ) = (c.num:ℚ) := by
    exact_mod_cast Int.toNat_of_nonneg (Rat.num_nonneg.mpr hc)
  have hc' : c = ((c.num.toNat:ℕ):ℚ)/c.den := by rw [hn, Rat.num_div_den]
  conv_lhs => rw [hc']
  have he : (P:ℚ)*((d:ℚ)*(((c.num.toNat:ℕ):ℚ)/c.den)/((m:ℚ)*(d:ℚ)^2)) =
      ((P*d*c.num.toNat:ℕ):ℚ)/((c.den*m*d^2:ℕ):ℚ) := by
    push_cast
    simp only [div_eq_mul_inv, mul_inv_rev]
    ring
  rw [he, Nat.floor_div_natCast, Nat.floor_natCast]

@[simp] theorem atom_bits {q : ℕ} (g : Instance q) (t : ℚ)
    (ht : t ∈ Set.Icc (-1:ℚ) 1) (K : ℕ) (y : Fin g.vertices)
    (e f : Fin g.constraints.length) (x z : Cube (Fin q)) :
    atom t ht K (bits g) y e f x z =
      ⌊(Game.gridSize (Fin g.vertices) (Fin g.constraints.length) q K:ℚ)*
        ((ofInstance g).sampleLaw t ht).weight (y,e,f,x,z)⌋₊ := by
  rw [InstanceAdapter.sampleLaw_weight]
  simp only [atom, row_target, Fin.val_inj, gridSize_bits, degree_bits, edges_bits]
  split_ifs
  · exact (rational_floor _ ((jointLaw t ht q).nonneg _) _ _ _).symm
  · simp

/-- Byte-oriented integer aggregation is exactly the rational rounded law.
This identity is independent of computational complexity assumptions. -/
theorem weights_bits {q : ℕ} (g : Instance q) (t : ℚ)
    (ht : t ∈ Set.Icc (-1:ℚ) 1) (K : ℕ)
    (anchor : Fin (g.vertices*2^q)) (u v : Fin (g.vertices*2^q)) :
    (ofInstance g).gridWeights t ht (vertexEquiv g.vertices q) anchor K u v =
      (weights q t ht K (bits g) u.val v.val : ℚ) / gridSize q K (bits g) := by
  rw [Game.gridWeights, roundedWeights_integer, gridSize_bits]
  by_cases huv : u=v
  · subst v; simp [weights]
  · have hval : u.val ≠ v.val := fun h => huv (Fin.ext h)
    simp only [huv, ↓reduceIte, weights, hval, vertices_bits, edges_bits]
    congr 2
    rw [Fintype.sum_prod_type]
    rw [← Fin.sum_univ_eq_sum_range]
    apply sum_congr rfl
    intro y hy
    rw [Fintype.sum_prod_type, ← Fin.sum_univ_eq_sum_range]
    apply sum_congr rfl
    intro e he
    rw [Fintype.sum_prod_type, ← Fin.sum_univ_eq_sum_range]
    apply sum_congr rfl
    intro f hf
    rw [Fintype.sum_prod_type]
    apply sum_congr rfl
    intro x hx
    apply sum_congr rfl
    intro z hz
    simp only [query_bits, atom_bits, Game.queries, ofInstance, Prod.mk.injEq, ← Fin.val_inj]

end OptimalMaxCut.RawGrid

end

end OAI