OAI/LinearAlgebra/MatrixMultiplication/AuxiliarySeparation/Convex/ConeSupport.lean

GitHub source file

4 declarations, 0 contain sorry, 0 declared as axioms

Independent generators for a finite conical combination

Every conical combination can be expressed using a linearly independent subfamily of its original generators.

  1. theorem OAI.MatrixMultiplication.AuxiliarySeparation.exists_positive_relation line 18
  2. theorem OAI.MatrixMultiplication.AuxiliarySeparation.exists_nonneg_representation_erase line 29
  3. theorem OAI.MatrixMultiplication.AuxiliarySeparation.exists_nonneg_representation_linearIndependent line 67

    Source documentation

    A nonnegative finite combination uses a linearly independent subfamily after possibly changing its coefficients.

    theorem exists_nonneg_representation_linearIndependent (A : I → E) (s : Finset I)
        (w : I → ℝ) (hw : ∀ i ∈ s, 0 ≤ w i) :
        ∃ t : Finset I, t ⊆ s ∧ LinearIndependent ℝ (fun i : t ↦ A i) ∧
          ∃ v : I → ℝ, (∀ i ∈ t, 0 ≤ v i) ∧
            (∑ i ∈ t, v i • A i) = ∑ i ∈ s, w i • A i := by
    …
  4. theorem OAI.MatrixMultiplication.AuxiliarySeparation.exists_linearIndependent_subcone line 83

    Source documentation

    Every element of a finitely generated cone belongs to the cone generated by some linearly independent subfamily of the given generators.

    theorem exists_linearIndependent_subcone [Fintype I] (A : I → E) {x : E}
        (hx : x ∈ PointedCone.hull ℝ (Set.range A)) :
        ∃ s : Finset I, LinearIndependent ℝ (fun i : s ↦ A i) ∧
          x ∈ PointedCone.hull ℝ (Set.range (fun i : s ↦ A i)) := by
    …