OAI/Analysis/MassAction/ActiveBranchMinimum.lean

GitHub source file

5 declarations, 0 contain sorry, 0 declared as axioms

  1. lemma OAI.Problem326.eventually_lt_right_of_hasDerivAt_pos line 13

    Source documentation

    A positive derivative gives strict increase immediately to the right.

    lemma eventually_lt_right_of_hasDerivAt_pos {f : ℝ → ℝ} {f' t : ℝ}
        (hf : HasDerivAt f f' t) (hpos : 0 < f') :
        ∀ᶠ u in 𝓝[>] t, f t < f u := by
    …
  2. lemma OAI.Problem326.finite_minimum_eventually_lt_right line 24

    Source documentation

    Finite lower envelopes increase to the right when every active branch has strictly positive derivative. Inactive branches only need continuity.

    lemma finite_minimum_eventually_lt_right {ι : Type uIota} (s : Finset ι)
        (hne : s.Nonempty) (f : ι → ℝ → ℝ) (t : ℝ)
        (hcont : ∀ i ∈ s, ContinuousWithinAt (f i) (Ioi t) t)
        (hderiv : ∀ i ∈ s, s.inf' hne (fun j => f j t) = f i t →
          ∃ v : ℝ, HasDerivAt (f i) v t ∧ 0 < v) :
        ∀ᶠ u in 𝓝[>] t, s.inf' hne (fun j => f j t) < s.inf' hne (fun j => f j u) := by
    …
  3. lemma OAI.Problem326.finite_minimum_add_const line 42

    Source documentation

    Adding the same constant commutes with a finite minimum.

    lemma finite_minimum_add_const {ι : Type uIota} (s : Finset ι) (hne : s.Nonempty)
        (f : ι → ℝ) (c : ℝ) :
        s.inf' hne (fun i => f i + c) = s.inf' hne f + c := by
    …
  4. theorem OAI.Problem326.finite_minimum_monotoneOn_Icc_of_active_deriv_nonneg line 54

    Source documentation

    A finite minimum whose active branches have nonnegative derivatives is nondecreasing. The left endpoint is included in the derivative hypothesis.

    theorem finite_minimum_monotoneOn_Icc_of_active_deriv_nonneg
        {ι : Type uIota} (s : Finset ι) (hne : s.Nonempty)
        (f : ι → ℝ → ℝ) (a b : ℝ)
        (hcont : ∀ i ∈ s, ContinuousOn (f i) (Icc a b))
        (hderiv : ∀ t ∈ Ico a b, ∀ i ∈ s,
          s.inf' hne (fun j => f j t) = f i t →
          ∃ v : ℝ, HasDerivAt (f i) v t ∧ 0 ≤ v) :
        MonotoneOn (fun t => s.inf' hne (fun i => f i t)) (Icc a b) := by
    …
  5. theorem OAI.Problem326.finite_minimum_monotoneOn_Icc_of_active_deriv_nonneg_Ioo line 106

    Source documentation

    Endpoint-continuous version: no derivatives are required at the endpoints.

    theorem finite_minimum_monotoneOn_Icc_of_active_deriv_nonneg_Ioo
        {ι : Type uIota} (s : Finset ι) (hne : s.Nonempty)
        (f : ι → ℝ → ℝ) (a b : ℝ)
        (hcont : ∀ i ∈ s, ContinuousOn (f i) (Icc a b))
        (hderiv : ∀ t ∈ Ioo a b, ∀ i ∈ s,
          s.inf' hne (fun j => f j t) = f i t →
          ∃ v : ℝ, HasDerivAt (f i) v t ∧ 0 ≤ v) :
        MonotoneOn (fun t => s.inf' hne (fun i => f i t)) (Icc a b) := by
    …