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FirstOrderMethodsOptimization_Beck_2017.Chap15.Definition_15_4

noncomputable def adpmm_proximal_objective {E : Type u} {F : Type v} [NormedAddCommGroup E] [InnerProductSpace E] [NormedAddCommGroup F] [NormedSpace F] (ρ : PosReal) (h : EEReal) (L : E →ₗ[] F) (P : E →ₗ[] E) (a : E) :
EEReal

The one-block proximal objective from Definition 15.4(D): u ↦ h(u) + (ρ / 2) ‖L u‖² + (1 / 2) ⟪u, P u⟫ + ⟪a, u⟫.

Instances For
    @[simp]
    theorem adpmm_proximal_objective_apply {E : Type u} {F : Type v} [NormedAddCommGroup E] [InnerProductSpace E] [NormedAddCommGroup F] [NormedSpace F] (ρ : PosReal) (h : EEReal) (L : E →ₗ[] F) (P : E →ₗ[] E) (a u : E) :
    adpmm_proximal_objective ρ h L P a u = h u + (ρ / 2 * L u ^ 2) + (1 / 2 * inner u (P u)) + (inner a u)

    Evaluating adpmm_proximal_objective gives h(u) + (ρ / 2) ‖L u‖² + (1 / 2) ⟪u, P u⟫ + ⟪a, u⟫.

    class IsADPMMProblem {X : Type u} {Z : Type v} {Y : Type w} [NormedAddCommGroup X] [InnerProductSpace X] [NormedAddCommGroup Z] [InnerProductSpace Z] [NormedAddCommGroup Y] [NormedSpace Y] (ρ : PosReal) (h₁ : XEReal) (h₂ : ZEReal) (A : X →ₗ[] Y) (B : Z →ₗ[] Y) (G : X →ₗ[] X) (Q : Z →ₗ[] Z) (c : Y) extends IsADMMConvexObjectivePair h₁ h₂ :

    Definition 15.4: Assumption 15.2 for the AD-PMM problem means that h₁ and h₂ form an ADMM convex objective pair, the proximal operators G and Q are symmetric positive semidefinite, every proximal one-block subproblem from clause (D) attains a minimizer, there exist x̂ ∈ ri(dom h₁) and ẑ ∈ ri(dom h₂) with A x̂ + B ẑ = c, and the canonical primal optimal set constrained_problem_solutions (H[h₁, h₂]) (admm_feasible_set A B c) is nonempty. The primal optimal value remains the canonical owner H_opt[h₁, h₂; A, B, c].

    Instances
      instance instFactOptimalSetNonemptyOfIsADPMMProblem {X : Type u} {Z : Type v} {Y : Type w} [NormedAddCommGroup X] [InnerProductSpace X] [NormedAddCommGroup Z] [InnerProductSpace Z] [NormedAddCommGroup Y] [NormedSpace Y] {ρ : PosReal} {h₁ : XEReal} {h₂ : ZEReal} {A : X →ₗ[] Y} {B : Z →ₗ[] Y} {G : X →ₗ[] X} {Q : Z →ₗ[] Z} {c : Y} (h : IsADPMMProblem ρ h₁ h₂ A B G Q c) :
      Fact (constrained_problem_solutions H[h₁, h₂] (admm_feasible_set A B c)).Nonempty

      Companion instance exposing nonemptiness of the canonical primal optimal set to typeclass search.