A Truncated SQP Method Based on Inexact Interior-Point Solutions of Subproblems

We consider sequential quadratic programming (SQP) methods applied to optimization problems with nonlinear equality constraints and simple bounds. In particular, we propose and analyze a truncated SQP algorithm in which subproblems are solved approximately by an infeasible predictor-corrector interior-point method, followed by setting to zero some variables and some multipliers so that complementarity conditions for approximate solutions are enforced. Verifiable truncation conditions based on the residual of optimality conditions of subproblems are developed to ensure both global and fast local convergence. Global convergence is established under assumptions that are standard for linesearch SQP with exact solution of subproblems. The local superlinear convergence rate is shown under the weakest assumptions that guarantee this property for pure SQP with exact solution of subproblems, namely, the strict Mangasarian-Fromovitz constraint qualification and second-order sufficiency. Local convergence results for our truncated method are presented as a special case of the local convergence for a more general perturbed SQP framework, which is of independent interest and is applicable even to some algorithms whose subproblems are not quadratic programs. For example, the framework can also be used to derive sharp local convergence results for linearly constrained Lagrangian methods. Preliminary numerical results confirm that it can be indeed beneficial to solve subproblems approximately, especially on early iterations.

[1]  Jean Charles Gilbert,et al.  Numerical Optimization: Theoretical and Practical Aspects , 2003 .

[2]  Jorge J. Moré,et al.  Digital Object Identifier (DOI) 10.1007/s101070100263 , 2001 .

[3]  Michael P. Friedlander,et al.  A Globally Convergent Linearly Constrained Lagrangian Method for Nonlinear Optimization , 2005, SIAM J. Optim..

[4]  J. F. Bonnans,et al.  Local analysis of Newton-type methods for variational inequalities and nonlinear programming , 1994 .

[5]  Stephen J. Wright Superlinear Convergence of a Stabilized SQP Method to a Degenerate Solution , 1998, Comput. Optim. Appl..

[6]  Ekkehard W. Sachs,et al.  Global Convergence of Inexact Reduced SQP Methods , 1995, Universität Trier, Mathematik/Informatik, Forschungsbericht.

[7]  Nicholas I. M. Gould,et al.  SQP Methods for Large-Scale Nonlinear Programming , 1999, System Modelling and Optimization.

[8]  Jorge Nocedal,et al.  An Interior Point Algorithm for Large-Scale Nonlinear Programming , 1999, SIAM J. Optim..

[9]  Alexey F. Izmailov,et al.  Sensitivity Analysis for Cone-Constrained Optimization Problems Under the Relaxed Constraint Qualifications , 2005, Math. Oper. Res..

[10]  Michael A. Saunders,et al.  A projected Lagrangian algorithm and its implementation for sparse nonlinear constraints , 1982 .

[11]  Mikhail V. Solodov,et al.  Stabilized sequential quadratic programming for optimization and a stabilized Newton-type method for variational problems , 2010, Math. Program..

[12]  Paul T. Boggs,et al.  Sequential Quadratic Programming , 1995, Acta Numerica.

[13]  Michael A. Saunders,et al.  SNOPT: An SQP Algorithm for Large-Scale Constrained Optimization , 2002, SIAM J. Optim..

[14]  S. M. Robinson Stability Theory for Systems of Inequalities, Part II: Differentiable Nonlinear Systems , 1976 .

[15]  S. Ulbrich Generalized SQP-Methods with ''Parareal'' Time-Domain Decomposition for Time-dependent PDE-constrained Optimization , 2007 .

[16]  Jorge Nocedal,et al.  An Inexact SQP Method for Equality Constrained Optimization , 2008, SIAM J. Optim..

[17]  R. Dembo,et al.  INEXACT NEWTON METHODS , 1982 .

[18]  N. Maratos,et al.  Exact penalty function algorithms for finite dimensional and control optimization problems , 1978 .

[19]  Stephen J. Wright Modifying SQP for Degenerate Problems , 2002, SIAM J. Optim..

[20]  Dimitri P. Bertsekas,et al.  Constrained Optimization and Lagrange Multiplier Methods , 1982 .

[21]  Jacek Gondzio,et al.  A New Unblocking Technique to Warmstart Interior Point Methods Based on Sensitivity Analysis , 2008, SIAM J. Optim..

[22]  Stephen J. Wright,et al.  Numerical Optimization , 2018, Fundamental Statistical Inference.

[23]  S. Glad Properties of updating methods for the multipliers in augmented Lagrangians , 1979 .

[24]  Walter Murray,et al.  Sequential quadratic programming methods based on indefinite Hessian approximations , 1999 .

[25]  Michael A. Saunders,et al.  MINOS 5. 0 user's guide , 1983 .

[26]  Dimitri P. Bertsekas,et al.  Nonlinear Programming , 1997 .

[27]  Matthias Heinkenschloss,et al.  An Inexact Trust-Region SQP Method with Applications to PDE-Constrained Optimization , 2008 .

[28]  Mikhail V. Solodov,et al.  On local convergence of sequential quadratically-constrained quadratic-programming type methods, with an extension to variational problems , 2008, Comput. Optim. Appl..

[29]  Claudia A. Sagastizábal,et al.  Parallel Variable Distribution for Constrained Optimization , 2002, Comput. Optim. Appl..

[30]  Michael A. Saunders,et al.  USER’S GUIDE FOR SNOPT 5.3: A FORTRAN PACKAGE FOR LARGE-SCALE NONLINEAR PROGRAMMING , 2002 .

[31]  Mikhail V. Solodov,et al.  Global convergence of an SQP method without boundedness assumptions on any of the iterative sequences , 2009 .

[32]  Klaus Schittkowski,et al.  More test examples for nonlinear programming codes , 1981 .

[33]  S. M. Robinson,et al.  A quadratically-convergent algorithm for general nonlinear programming problems , 1972, Math. Program..

[34]  Mikhail V. Solodov,et al.  On the Sequential Quadratically Constrained Quadratic Programming Methods , 2004, Math. Oper. Res..

[35]  Ekkehard W. Sachs,et al.  Inexact SQP Interior Point Methods and Large Scale Optimal Control Problems , 1999, SIAM J. Control. Optim..

[36]  William W. Hager,et al.  Stabilized Sequential Quadratic Programming , 1999, Comput. Optim. Appl..

[37]  Luís N. Vicente,et al.  Analysis of Inexact Trust-Region SQP Algorithms , 2002, SIAM J. Optim..

[38]  Alexey F. Izmailov,et al.  On attraction of linearly constrained Lagrangian methods and of stabilized and quasi-Newton SQP methods to critical multipliers , 2011, Math. Program..

[39]  JON W. TOLLEMathematics,et al.  A Truncated Sqp Algorithm for Large Scale Nonlinear Programming Problems , 2007 .

[40]  N. Gould Some Reflections on the Current State of Active-Set and Interior-Point Methods for Constrained Op , 2003 .

[41]  Nicholas I. M. Gould,et al.  Numerical methods for large-scale nonlinear optimization , 2005, Acta Numerica.

[42]  Masao Fukushima,et al.  A Sequential Quadratically Constrained Quadratic Programming Method for Differentiable Convex Minimization , 2002, SIAM J. Optim..

[43]  Francisco J. Prieto,et al.  A Sequential Quadratic Programming Algorithm Using an Incomplete Solution of the Subproblem , 1995, SIAM J. Optim..

[44]  Mihai Anitescu,et al.  A Superlinearly Convergent Sequential Quadratically Constrained Quadratic Programming Algorithm for Degenerate Nonlinear Programming , 2002, SIAM J. Optim..

[45]  Alexey F. Izmailov,et al.  Inexact Josephy–Newton framework for generalized equations and its applications to local analysis of Newtonian methods for constrained optimization , 2010, Comput. Optim. Appl..

[46]  Jorge Nocedal,et al.  An inexact Newton method for nonconvex equality constrained optimization , 2009, Math. Program..

[47]  Klaus Schittkowski,et al.  Test examples for nonlinear programming codes , 1980 .

[48]  Jorge Nocedal,et al.  On the Implementation of an Algorithm for Large-Scale Equality Constrained Optimization , 1998, SIAM J. Optim..

[49]  邵文革,et al.  Gilbert综合征二例 , 2009 .

[50]  J. Frédéric Bonnans,et al.  Perturbation Analysis of Optimization Problems , 2000, Springer Series in Operations Research.