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IntroductoryLecturesOnConvexOptimization_Nesterov_2004.Chap03.Definition_3_21

def compositeObjective {X : Type u} (f : X) (Ψ : XWithTop ) :
XWithTop

The extended composite objective x ↦ f x + Ψ x built from a real-valued smooth term and an extended-valued regularizer on the same ambient space.

Instances For
    @[simp]
    theorem compositeObjective_apply {X : Type u} (f : X) (Ψ : XWithTop ) (x : X) :
    compositeObjective f Ψ x = (f x) + Ψ x

    Evaluating the extended composite objective recovers the defining sum f x + Ψ x.

    structure CompositeConvexMinimizationProblem (E : Type u) [NormedAddCommGroup E] [NormedSpace E] extends SetConstrainedMinimizationProblem E :

    Definition 3.21, generalized from the textbook ℝⁿ setting: a composite convex minimization problem consists of a closed feasible set Q, a smooth convex part f that belongs to ConvexC1On Q, and a closed convex term Ψ on Q, representing the objective x ↦ f x + Ψ x minimized over Q. The ambient smooth pair (Q, f) is owned canonically by SetConstrainedMinimizationProblem, the smooth regularity/convexity package by ConvexC1On, and the nonsmooth term by ClosedConvexOn. The textbook ℝⁿ case is the specialization CompositeConvexMinimizationProblem (EuclideanSpace ℝ (Fin n)).

    Instances For
      @[reducible, inline]
      abbrev CompositeConvexMinimizationProblem.smoothPart {E : Type u} [NormedAddCommGroup E] [NormedSpace E] (problem : CompositeConvexMinimizationProblem E) :
      E

      The source-facing smooth term f is the inherited Chapter 1 objective.

      Instances For
        theorem CompositeConvexMinimizationProblem.smoothPart_convex {E : Type u} [NormedAddCommGroup E] [NormedSpace E] (problem : CompositeConvexMinimizationProblem E) :
        ConvexOn problem.feasibleSet problem.smoothPart

        The smooth term is convex on the feasible set Q.

        theorem CompositeConvexMinimizationProblem.smoothPart_contDiff {E : Type u} [NormedAddCommGroup E] [NormedSpace E] (problem : CompositeConvexMinimizationProblem E) :
        ContDiffOn 1 problem.smoothPart problem.feasibleSet

        The smooth term is on the feasible set Q.

        theorem CompositeConvexMinimizationProblem.feasibleSet_convex {E : Type u} [NormedAddCommGroup E] [NormedSpace E] (problem : CompositeConvexMinimizationProblem E) :
        Convex problem.feasibleSet

        The feasible set of a composite convex minimization problem is convex.

        @[implicit_reducible]
        instance CompositeConvexMinimizationProblem.instCoeFunForallWithTopReal {E : Type u} [NormedAddCommGroup E] [NormedSpace E] :

        A composite convex minimization problem can be used as its extended-valued objective x ↦ f(x) + Ψ(x).

        @[simp]
        theorem CompositeConvexMinimizationProblem.coe_apply {E : Type u} [NormedAddCommGroup E] [NormedSpace E] (problem : CompositeConvexMinimizationProblem E) (x : E) :
        compositeObjective problem.smoothPart problem.nonsmoothPart x = (problem.smoothPart x) + problem.nonsmoothPart x

        Evaluating a composite convex minimization problem gives its composite objective value.