File size: 5,729 Bytes
0dd3af4
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
import Mathlib
import OAI.GroupTheory.SimpleOvergroups.ActionMonoid
import OAI.GroupTheory.SimpleOvergroups.NamedActions

namespace OAI


noncomputable section
open scoped Classical
namespace SimpleFInftyOvergroups.SemanticEncoding
open BoundedEncoding NamedAction
namespace SemanticActionMonoid

variable {G X V Y K L : Type*} [Group V] [MulAction V Y] {m : ℕ}
  {N : Operations G X} {C : ActionCalculus V Y K L m} (I : Interpretation N C)

abbrev groupValue (g : G) : V := (I.group g).val
abbrev pointValue (x : X) : Y := (I.point x).val

def letter : Letter G X → SourceActionMonoid.Generator V Y
  | .inl g => .grp (groupValue I g)
  | .inr (.inl x) => .pre (pointValue I x)
  | .inr (.inr (some x)) => .delete (pointValue I x)
  | .inr (.inr none) => .zero

def wordMap : FreeMonoid (Letter G X) →* SourceActionMonoid.M V Y :=
  (PresentedMonoid.mk (SourceActionMonoid.Relation V Y)).comp
    (FreeMonoid.lift (fun a => FreeMonoid.of (letter I a)))

def formValue : Form G X → SourceActionMonoid.Algorithm.Form (V:=V) (Z:=Y) :=
  Operations.formKey (groupValue I) (pointValue I)

 theorem formKey_injective {G X : Type*} {kg : G → K} {kx : X → L}
    (hg : Function.Injective kg) (hx : Function.Injective kx) :
    Function.Injective (Operations.formKey kg kx) := by
  apply Option.map_injective
  intro a b h
  apply Prod.ext
  · exact (List.map_injective_iff.mpr hx) (congrArg Prod.fst h)
  · apply Prod.ext
    · exact hg (congrArg (fun p => p.2.1) h)
    · exact (List.map_injective_iff.mpr hx) (congrArg (fun p => p.2.2) h)

 theorem formKey_comp (f : Form G X) :
    Operations.formKey C.group.key C.point.key (formValue I f) =
      Operations.formKey I.gkey I.xkey f := by
  cases f with
  | none => rfl
  | some p => simp only [Operations.formKey,formValue,Option.map_some,List.map_map]; rfl

variable [DecidableEq L]

 theorem formValue_step (hx : Function.Injective C.point.key)
    (a : Letter G X) (f : Form G X) :
    formValue I (N.totalStep I.xkey a f) =
      SourceActionMonoid.Algorithm.step (letter I a) (formValue I f) := by
  have hone : groupValue I N.one = 1 := congrArg WithBound.val I.one
  have hmul g h : groupValue I (N.mul g h) = groupValue I g * groupValue I h :=
    congrArg WithBound.val (I.mul g h)
  have hinv g : groupValue I (N.inv g) = (groupValue I g)⁻¹ :=
    congrArg WithBound.val (I.inv g)
  have hact g x : pointValue I (N.act g x) = groupValue I g • pointValue I x :=
    congrArg WithBound.val (I.act g x)
  have hkey x y : I.xkey x = I.xkey y ↔ pointValue I x = pointValue I y := hx.eq_iff
  cases f with
  | none => cases a <;> rfl
  | some p =>
    rcases p with ⟨l,g,r⟩
    rcases a with h | (x | y)
    · cases l <;> simp [Operations.totalStep,Operations.plan,formValue,Operations.formKey,
        letter,SourceActionMonoid.Algorithm.step,hmul,hact]
    · rfl
    · cases y with
      | none => rfl
      | some y =>
        cases l with
        | nil => simp [Operations.totalStep,Operations.plan,formValue,Operations.formKey,
            letter,SourceActionMonoid.Algorithm.step,hone,hact,hinv]
        | cons x l =>
          by_cases h : I.xkey y = I.xkey x
          · simp [Operations.totalStep,Operations.plan,formValue,Operations.formKey,
              letter,SourceActionMonoid.Algorithm.step,h,(hkey y x).mp h]
          · simp [Operations.totalStep,Operations.plan,formValue,Operations.formKey,
              letter,SourceActionMonoid.Algorithm.step,h,mt (hkey y x).mpr h]

 theorem formValue_normalize (hx : Function.Injective C.point.key) (w : List (Letter G X)) :
    formValue I (N.totalNormalize I.xkey w) = SourceActionMonoid.Algorithm.normalize (w.map (letter I)) := by
  induction w with
  | nil =>
    change some ([],groupValue I N.one,[]) = some ([],1,[])
    rw [show groupValue I N.one = 1 from congrArg WithBound.val I.one]
  | cons a w ih =>
    change formValue I (N.totalStep I.xkey a (N.totalNormalize I.xkey w)) = _
    rw [formValue_step I hx,ih]
    rfl

omit [DecidableEq L] in
 theorem wordMap_ofList (w : List (Letter G X)) :
    wordMap I (FreeMonoid.ofList w) =
      PresentedMonoid.mk (SourceActionMonoid.Relation V Y) (FreeMonoid.ofList (w.map (letter I))) := by
  induction w with
  | nil => rfl
  | cons a w ih => simp only [FreeMonoid.ofList_cons,map_mul,List.map_cons,ih]; rfl

 theorem totalTest_eq_iff (hg : Function.Injective C.group.key) (hx : Function.Injective C.point.key)
    (u v : List (Letter G X)) :
    N.totalTest I.gkey I.xkey u = N.totalTest I.gkey I.xkey v ↔
      wordMap I (FreeMonoid.ofList u) = wordMap I (FreeMonoid.ofList v) := by
  change Operations.formKey I.gkey I.xkey _ = Operations.formKey I.gkey I.xkey _ ↔ _
  rw [← formKey_comp I,← formKey_comp I,(formKey_injective hg hx).eq_iff,
    formValue_normalize I hx,formValue_normalize I hx,wordMap_ofList,wordMap_ofList]
  exact (SourceActionMonoid.Algorithm.word_eq_iff _ _).symm

omit [DecidableEq L] in
 theorem wordMap_surjective (hg : Function.Surjective (groupValue I))
    (hx : Function.Surjective (pointValue I)) : Function.Surjective (wordMap I) := by
  have hl : Function.Surjective (letter I) := by
    intro a
    cases a with
    | grp g => obtain ⟨a,rfl⟩ := hg g; exact ⟨.inl a,rfl⟩
    | pre y => obtain ⟨a,rfl⟩ := hx y; exact ⟨.inr (.inl a),rfl⟩
    | delete y => obtain ⟨a,rfl⟩ := hx y; exact ⟨.inr (.inr (some a)),rfl⟩
    | zero => exact ⟨.inr (.inr none),rfl⟩
  intro z
  obtain ⟨v,rfl⟩ := PresentedMonoid.surjective_mk z
  obtain ⟨w,hw⟩ := (List.map_surjective_iff.mpr hl) v.toList
  refine ⟨FreeMonoid.ofList w,?_⟩
  rw [wordMap_ofList,hw,FreeMonoid.ofList_toList]

end SemanticActionMonoid
end SimpleFInftyOvergroups.SemanticEncoding
end

end OAI