OAI/GroupTheory/PolycyclicRecognition/Algebra/FiniteCutoffPartition.lean

GitHub source file

7 declarations, 0 contain sorry, 0 declared as axioms

The quantitative cutoff partition used by Lipschitz replacement

  1. def OAI.PolycyclicRecognition.cutoffMass line 16

    Source documentation

    Unnormalized radius-two distance cutoffs in the sum norm.

    def cutoffMass (v : I → X) (x : X) : PiLp 1 (fun _ : I => ℝ) :=
    …
  2. def OAI.PolycyclicRecognition.cutoffPartition line 19
  3. theorem OAI.PolycyclicRecognition.cutoff_difference_le line 22
  4. theorem OAI.PolycyclicRecognition.norm_cutoffMass_sub_le line 30

    Source documentation

    Before normalization, at most one distance error is charged per participating center. The application restricts to the finite local support.

    theorem norm_cutoffMass_sub_le (v : I → X) (x y : X) :
        ‖cutoffMass v x - cutoffMass v y‖ ≤ (Fintype.card I : ℝ) * dist x y := by
    …

    Mentions: OAI.PolycyclicRecognition.cutoffMass

  5. theorem OAI.PolycyclicRecognition.one_le_norm_cutoffMass line 39

    Source documentation

    The unit-ball cover gives the uniform lower bound on the denominator.

    theorem one_le_norm_cutoffMass (v : I → X) (x : X)
        (hcover : ∃ i, dist x (v i) ≤ 1) : 1 ≤ ‖cutoffMass v x‖ := by
    …

    Mentions: OAI.PolycyclicRecognition.cutoffMass

  6. theorem OAI.PolycyclicRecognition.norm_cutoffPartition_sub_le line 51

    Source documentation

    Normalization costs a factor two, uniformly over points whose unit balls contain one of the participating centers.

    theorem norm_cutoffPartition_sub_le (v : I → X) (x y : X)
        (hx : ∃ i, dist x (v i) ≤ 1) (hy : ∃ i, dist y (v i) ≤ 1) :
        ‖cutoffPartition v x - cutoffPartition v y‖ ≤
          2 * (Fintype.card I : ℝ) * dist x y := by
    …

    Mentions: OAI.PolycyclicRecognition.cutoffPartition

  7. theorem OAI.PolycyclicRecognition.cutoffPartition_probability line 61

    Source documentation

    These are genuine barycentric coordinates, with nonnegative entries and total mass exactly one.

    theorem cutoffPartition_probability (v : I → X) (x : X)
        (hcover : ∃ i, dist x (v i) ≤ 1) :
        (∀ i, 0 ≤ cutoffPartition v x i) ∧ (∑ i, cutoffPartition v x i) = 1 := by
    …

    Mentions: OAI.PolycyclicRecognition.cutoffPartition