Theorems · Definition · real analysis

logDeriv

{𝕜 : Type u_1} →
  {𝕜' : Type u_2} →
    [inst : NontriviallyNormedField 𝕜] →
      [inst_1 : NontriviallyNormedField 𝕜'] → [NormedAlgebra 𝕜 𝕜'] → (𝕜 → 𝕜') → 𝕜 → 𝕜'

The logarithmic derivative of a function defined as deriv f /f. Note that it will be zero at x if f is not DifferentiableAt x.

Defined in

Mathlib.Analysis.Calculus.LogDeriv

Cited by

71 results in Mathlib

Foundations

Depth 105 from the axioms · uses propext, Classical.choice, Quot.sound

Assumes

NontriviallyNormedFieldNontriviallyNormedFieldNormedAlgebra