OAI/NumberTheory/Ostmann/Characters/LogCutoffPolynomial.lean
5 declarations, 0 contain sorry, 0 declared as axioms
Polynomial factors for the actual logarithmic node cutoff
- theorem
OAI.Ostmann.log_lipschitz_on_positive_rayline 10 - def
OAI.Ostmann.positiveLogCutoffline 32 - def
OAI.Ostmann.logCutoffPolynomialFactorline 37Source documentation
The center appears in the lower endpoint and its reciprocal Lipschitz constant. These cancel in the total variation budget.
noncomputable def logCutoffPolynomialFactor (P : Polynomial ℝ) (φ : ℝ → ℝ) (G B D : ℝ) (hB : 0 ≤ B) (hD : 0 ≤ D) (hφ : ∀ x, |φ x| ≤ B) (hlip : ∀ x y, |φ x - φ y| ≤ D * |x - y|) : ClippedPolynomialFactor where …Mentions: OAI.Ostmann.ClippedPolynomialFactor
- theorem
OAI.Ostmann.logCutoffPolynomialFactor_valueline 62Source documentation
Clipping changes no node factor, including nonpositive inserted values and both boundary points of the compact logarithmic cutoff.
theorem logCutoffPolynomialFactor_value (P : Polynomial ℝ) (φ : ℝ → ℝ) (G B D : ℝ) (hB : 0 ≤ B) (hD : 0 ≤ D) (hφ : ∀ x, |φ x| ≤ B) (hlip : ∀ x y, |φ x - φ y| ≤ D * |x - y|) (hout : ∀ x, 1 ≤ |x| → φ x = 0) (z : ℝ) : (logCutoffPolynomialFactor P φ G B D hB hD hφ hlip).value z = (positiveLogCutoff φ G (P.eval z) : ℂ) := by …Mentions: OAI.Ostmann.logCutoffPolynomialFactor, OAI.Ostmann.positiveLogCutoff
- theorem
OAI.Ostmann.logCutoffPolynomialFactor_budgetline 102Source documentation
No large-center cost occurs in a logarithmic node cutoff's variation.
theorem logCutoffPolynomialFactor_budget (P : Polynomial ℝ) (φ : ℝ → ℝ) (G B D : ℝ) (hB : 0 ≤ B) (hD : 0 ≤ D) (hφ : ∀ x, |φ x| ≤ B) (hlip : ∀ x y, |φ x - φ y| ≤ D * |x - y|) : let f := logCutoffPolynomialFactor P φ G B D hB hD hφ hlip …Mentions: OAI.Ostmann.logCutoffPolynomialFactor