OAI/NumberTheory/Ostmann/Arithmetic/MovingPivotDerivative.lean

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5 declarations, 0 contain sorry, 0 declared as axioms

Logarithmic differentiation through the actual moving pivot

  1. theorem OAI.Ostmann.moving_pivot_cancellation_budget line 12

    Source documentation

    The cancellation cost is derived from the actual child-product and pivot ranges. The large common logarithmic center cancels exactly.

    theorem moving_pivot_cancellation_budget (v w HL HR d p T Δ E C : ℝ)
        (hv : |v| ≤ Real.exp E) (hw : |w| ≤ Real.exp E)
        (hHL : |HL| ≤ Real.exp (T + C)) (hHR : |HR| ≤ Real.exp (T + C))
        (hden : Real.exp (T - Δ - C) ≤ |d| * p) :
        |v * HR| + |w * HL| ≤ Real.exp (Real.log 2 + E + Δ + 2 * C) * (|d| * p) := by
    …
  2. theorem OAI.Ostmann.moving_pivot_relative_derivative line 32

    Source documentation

    Relative derivatives are stable through a linear pivot, with precisely the cancellation factor supplied by the range estimate above.

    theorem moving_pivot_relative_derivative (a b d X Y dX dY p A D : ℝ)
        (hd : d ≠ 0) (hX : 0 ≤ X) (hY : 0 ≤ Y) (hD : 0 ≤ D)
        (hDX : |dX| ≤ D * X) (hDY : |dY| ≤ D * Y)
        (hcancel : |a * Y| + |b * X| ≤ A * |d| * p) :
        |(a * dY - b * dX) / d| ≤ A * D * p := by
    …
  3. theorem OAI.Ostmann.MovingSlotReversal.realPivot_hasDerivAt line 56
  4. theorem OAI.Ostmann.MovingSlotReversal.log_realPivot_derivative line 68

    Source documentation

    This is the derivative of the logarithm used by every internal smooth cutoff. It applies to the literal moving-pivot formula.

    theorem MovingSlotReversal.log_realPivot_derivative {σ : Type*}
        (step : MovingSlotReversal σ) (value : σ → ℕ)
        {L R : ℝ → ℝ} {x dL dR : ℝ} (hL : HasDerivAt L dL x) (hR : HasDerivAt R dR x)
        (hp : 0 < step.realPivot value (L x) (R x)) :
        HasDerivAt (fun z => Real.log (step.realPivot value (L z) (R z)))
          (step.realPivot value dL dR / step.realPivot value (L x) (R x)) x :=
    …

    Mentions: OAI.Ostmann.MovingSlotReversal

  5. theorem OAI.Ostmann.MovingSlotReversal.log_realPivot_derivative_bound line 78

    Source documentation

    The logarithmic derivative costs at most the cancellation factor times the incoming logarithmic derivative bound.

    theorem MovingSlotReversal.log_realPivot_derivative_bound {σ : Type*}
        (step : MovingSlotReversal σ) (value : σ → ℕ)
        (X Y dX dY A D : ℝ) (hs : step.rootFrequency ≠ 0)
        (hu : MovingSlotReversal.naturalProduct value step.compensationSlots ≠ 0)
        (hX : 0 ≤ X) (hY : 0 ≤ Y) (hD : 0 ≤ D)
        (hDX : |dX| ≤ D * X) (hDY : |dY| ≤ D * Y)
        (hp : 0 < step.realPivot value X Y)
        (hcancel : |(step.leftFrequency : ℝ) *
            (MovingSlotReversal.naturalProduct value step.rightSlots : ℝ) * Y| +
          |(step.rightFrequency : ℝ) *
            (MovingSlotReversal.naturalProduct value step.leftSlots : ℝ) * X| ≤
          A * |(step.rootFrequency : ℝ) *
    …

    Mentions: OAI.Ostmann.MovingSlotReversal, OAI.Ostmann.MovingSlotReversal.naturalProduct