Direct search based on probabilistic feasible descent for bound and linearly constrained problems

S. Gratton, C. W. Royer, L. N. Vicente, Z. Zhang

Research output: Journal article publicationJournal articleAcademic researchpeer-review

11 Citations (Scopus)


Direct search is a methodology for derivative-free optimization whose iterations are characterized by evaluating the objective function using a set of polling directions. In deterministic direct search applied to smooth objectives, these directions must somehow conform to the geometry of the feasible region, and typically consist of positive generators of approximate tangent cones (which then renders the corresponding methods globally convergent in the linearly constrained case). One knows however from the unconstrained case that randomly generating the polling directions leads to better complexity bounds as well as to gains in numerical efficiency, and it becomes then natural to consider random generation also in the presence of constraints. In this paper, we study a class of direct-search methods based on sufficient decrease for solving smooth linearly constrained problems where the polling directions are randomly generated (in approximate tangent cones). The random polling directions must satisfy probabilistic feasible descent, a concept which reduces to probabilistic descent in the absence of constraints. Such a property is instrumental in establishing almost-sure global convergence and worst-case complexity bounds with overwhelming probability. Numerical results show that the randomization of the polling directions can be beneficial over standard approaches with deterministic guarantees, as it is suggested by the respective worst-case complexity bounds.

Original languageEnglish
Pages (from-to)525-559
Number of pages35
JournalComputational Optimization and Applications
Issue number3
Publication statusPublished - 15 Apr 2019


  • Bound constraints
  • Derivative-free optimization
  • Direct-search methods
  • Feasible descent
  • Linear constraints
  • Probabilistic feasible descent
  • Worst-case complexity

ASJC Scopus subject areas

  • Control and Optimization
  • Computational Mathematics
  • Applied Mathematics


Dive into the research topics of 'Direct search based on probabilistic feasible descent for bound and linearly constrained problems'. Together they form a unique fingerprint.

Cite this