OAI/Analysis/MetricEntropy/LabelEncoding.lean

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7 declarations, 0 contain sorry, 0 declared as axioms

Fixed encodings of realized partition labels

Only the realized labels are counted. The ambient label types need not be finite, and representatives are fixed from the label maps alone, before any coefficient vector enters the compression construction.

  1. structure OAI.MetricEntropyDuality.FixedLabels line 23

    Source documentation

    Shared finite label data for a family of partitions. A representative is defined at every code, including unused codes, and preserves each realized label when applied to its encoding.

    structure FixedLabels {X : Type uX} {u : ℕ} {Label : Fin u → Type uLabel}
        (L : (i : Fin u) → X → Label i) (q : ℕ) where
    …
  2. def OAI.MetricEntropyDuality.FixedLabels.rangeEmbedding line 37

    Source documentation

    Embed the finite range, rather than the entire ambient label type.

    def rangeEmbedding {Y : Type uY} [Finite X] (f : X → Y) (q : ℕ)
        (hcard : Nat.card (Set.range f) ≤ q) : Set.range f ↪ Fin q :=
    …
  3. def OAI.MetricEntropyDuality.FixedLabels.ofCardBound line 45

    Source documentation

    Construct all encodings and representative maps from the fixed label family and its realized-cardinality bounds. The construction has no measure or coefficient-vector parameter. Nonempty X supplies a representative even at codes outside the encoding's image.

    def ofCardBound [Finite X] [Nonempty X]
        (L : (i : Fin u) → X → Label i)
        (hcard : ∀ i, Nat.card (Set.range (L i)) ≤ q) : FixedLabels L q := by
    …

    Mentions: OAI.MetricEntropyDuality.FixedLabels

  4. theorem OAI.MetricEntropyDuality.FixedLabels.encode_representative_encode line 65

    Source documentation

    Replacing a vertex by its fixed representative keeps its finite code.

    theorem encode_representative_encode (E : FixedLabels L q) (i : Fin u) (x : X) :
        E.encode i (E.representative i (E.encode i x)) = E.encode i x :=
    …

    Mentions: OAI.MetricEntropyDuality.FixedLabels

  5. theorem OAI.MetricEntropyDuality.FixedLabels.representative_encode_eq_of_label_eq line 70

    Source documentation

    Equal labels select the same fixed representative.

    theorem representative_encode_eq_of_label_eq (E : FixedLabels L q)
        (i : Fin u) {x y : X} (h : L i x = L i y) :
        E.representative i (E.encode i x) = E.representative i (E.encode i y) := by
    …

    Mentions: OAI.MetricEntropyDuality.FixedLabels

  6. def OAI.MetricEntropyDuality.FixedLabels.paddingCode line 76

    Source documentation

    A fixed vertex supplies a realized code for padding unused pivot slots.

    def paddingCode [Nonempty X] (E : FixedLabels L q) (i : Fin u) : Fin q :=
    …

    Mentions: OAI.MetricEntropyDuality.FixedLabels

  7. theorem OAI.MetricEntropyDuality.FixedLabels.paddingCode_realized line 79