theorem
proved
chartCompatible_symm
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IndisputableMonolith.RecogGeom.Charts on GitHub at line 116.
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All declarations in this module, on Recognition.
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113 rfl
114
115/-- Chart compatibility is symmetric -/
116theorem chartCompatible_symm (φ₁ φ₂ : RecognitionChart L r n)
117 (hcompat : ChartCompatible L r φ₁ φ₂) :
118 ChartCompatible L r φ₂ φ₁ := by
119 intro c h₂ h₁
120 exact (hcompat c h₁ h₂).symm
121
122/-! ## Recognition Atlas -/
123
124/-- A recognition atlas is a family of compatible charts that cover the space -/
125structure RecognitionAtlas (L : LocalConfigSpace C) (r : Recognizer C E) (n : ℕ) where
126 /-- The family of charts (indexed by some type) -/
127 charts : Set (RecognitionChart L r n)
128 /-- The charts are pairwise compatible -/
129 compatible : ∀ φ₁ ∈ charts, ∀ φ₂ ∈ charts, ChartCompatible L r φ₁ φ₂
130 /-- The charts cover the configuration space -/
131 covers : ∀ c : C, ∃ φ ∈ charts, c ∈ φ.domain
132
133/-- An atlas covers the quotient space -/
134theorem atlas_covers_quotient (A : RecognitionAtlas L r n) (q : RecognitionQuotient r) :
135 ∃ φ ∈ A.charts, ∃ c ∈ φ.domain, recognitionQuotientMk r c = q := by
136 obtain ⟨c, hc⟩ := Quotient.exists_rep q
137 obtain ⟨φ, hφ, hcφ⟩ := A.covers c
138 refine ⟨φ, hφ, c, hcφ, ?_⟩
139 -- hc : ⟦c⟧ = q
140 -- recognitionQuotientMk r c = Quotient.mk _ c = ⟦c⟧
141 simp only [recognitionQuotientMk]
142 exact hc
143
144/-! ## Recognition Dimension -/
145
146/-- The recognition dimension at a point is the dimension of any chart containing it -/