Constrained Nonlinear Optimization

ALESQP: An augmented Lagrangian equality-constrained SQP method for optimization with general constraints

  • Harbir Antil
  • Drew P. Kouri
  • Denis Ridzal
    • Categories Constrained Nonlinear Optimization, Infinite Dimensional Optimization, Nonlinear Optimization

    We present a new algorithm for infinite-dimensional optimization with general constraints, called ALESQP. In short, ALESQP is an augmented Lagrangian method that penalizes inequality constraints and solves equality-constrained nonlinear optimization subproblems at every iteration. The subproblems are solved using a matrix-free trust-region sequential quadratic programming (SQP) method that takes advantage of iterative, i.e., inexact linear … Read more

    Weak notions of nondegeneracy in nonlinear semidefinite programming

  • Roberto Andreani
  • Gabriel Haeser
  • Leonardo M. Mito
  • Héctor Ramírez
    • Categories Constrained Nonlinear Optimization, Linear, Cone and Semidefinite Programming, Semi-definite Programming Tags , ,

    The constraint nondegeneracy condition is one of the most relevant and useful constraint qualifications in nonlinear semidefinite programming. It can be characterized in terms of any fixed orthonormal basis of the, let us say, $\ell$-dimensional kernel of the constraint matrix, by the linear independence of a set of $\ell(\ell+1)/2$ derivative vectors. We show that this … Read more

    A Distributed and Secure Algorithm for Computing Dominant SVD Based on Projection Splitting

  • Xin Liu
  • Lei Wang
  • Yin Zhang
    • Categories Constrained Nonlinear Optimization, Parallel Algorithms Tags , , ,

    In this paper, we propose and study a distributed and secure algorithm for computing dominant (or truncated) singular value decompositions (SVD) of large and distributed data matrices. We consider the scenario where each node privately holds a subset of columns and only exchanges “safe” information with other nodes in a collaborative effort to calculate a … Read more

    Multipliers Correction Methods for Optimization Problems over the Stiefel Manifold

  • Bin Gao
  • Xin Liu
  • Lei Wang
    • Categories Constrained Nonlinear Optimization Tags , , ,

    We propose a class of multipliers correction methods to minimize a differentiable function over the Stiefel manifold. The proposed methods combine a function value reduction step with a proximal correction step. The former one searches along an arbitrary descent direction in the Euclidean space instead of a vector in the tangent space of the Stiefel … Read more

    Homogeneous polynomials and spurious local minima on the unit sphere

  • Jean-Bernard Lasserre
    • Categories Constrained Nonlinear Optimization, Global Optimization Theory

    We consider forms on the Euclidean unit sphere. We obtain obtain a simple and complete characterization of all points that satisfies the standard second-order necessary condition of optimality. It is stated solely in terms of the value of (i) f, (ii) the norm of its gradient, and (iii) the first two smallest eigenvalues of its … Read more

    Constrained stochastic blackbox optimization using a progressive barrier and probabilistic estimates

  • Kwassi Joseph Dzahini
  • Michael Kokkolaras
  • Sébastien Le Digabel
    • Categories Constrained Nonlinear Optimization, Nonlinear Optimization, Stochastic Approaches Tags , , ,

    This work introduces the StoMADS-PB algorithm for constrained stochastic blackbox optimization, which is an extension of the mesh adaptive direct-search (MADS) method originally developed for deterministic blackbox optimization under general constraints. The values of the objective and constraint functions are provided by a noisy blackbox, i.e., they can only be computed with random noise whose … Read more

    Exterior-point Optimization for Nonconvex Learning

  • Shuvomoy Das Gupta
  • Bartolomeo Stellato
  • Bart Paul Gerard Van Parys
    • Categories Constrained Nonlinear Optimization, Nonsmooth Optimization, Statistics Tags , , ,

    In this paper we present the nonconvex exterior-point optimization solver (NExOS)—a novel first-order algorithm tailored to constrained nonconvex learning problems. We consider the problem of minimizing a convex function over nonconvex constraints, where the projection onto the constraint set is single-valued around local minima. A wide range of nonconvex learning problems have this structure including … Read more

    A Reformulation-Linearization Technique for Optimization over Simplices

  • Aras Selvi
  • Dick den Hertog
  • Wolfram Wiesemann
    • Categories Constrained Nonlinear Optimization, Global Optimization, Global Optimization Theory Tags , ,

    We study non-convex optimization problems over simplices. We show that for a large class of objective functions, the convex approximation obtained from the Reformulation-Linearization Technique (RLT) admits optimal solutions that exhibit a sparsity pattern. This characteristic of the optimal solutions allows us to conclude that (i) a linear matrix inequality constraint, which is often added … Read more

    An Inertial Block Majorization Minimization Framework for Nonsmooth Nonconvex Optimization

  • Nicolas Gillis
  • Le Thi Khanh Hien
  • Duy Nhat Phan
    • Categories Constrained Nonlinear Optimization Tags , , , , ,

    In this paper, we introduce TITAN, a novel inerTial block majorIzation minimization framework for non-smooth non-convex opTimizAtioN problems. TITAN is a block coordinate method (BCM) that embeds inertial force to each majorization-minimization step of the block updates. The inertial force is obtained via an extrapolation operator that subsumes heavy-ball and Nesterov-type accelerations for block proximal … Read more

    Tight bounds on the maximal perimeter and the maximal width of convex small polygons

  • Christian Bingane
    • Categories Constrained Nonlinear Optimization, Convex Optimization, Quadratic Programming Tags , , , , ,

    A small polygon is a polygon of unit diameter. The maximal perimeter and the maximal width of a convex small polygon with $n=2^s$ vertices are not known when $s \ge 4$. In this paper, we construct a family of convex small $n$-gons, $n=2^s$ and $s\ge 3$, and show that the perimeters and the widths obtained … Read more