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What Is Optimization Toolbox?

What Is Optimization Toolbox?

What Is Optimization Toolbox?

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fmincon• A dense (or fairly dense) column of matrix Aeq can result inconsiderable fill and computational cost.• fmincon removes (numerically) linearly dependent rows in Aeq;however, this process involves repeated matrix factorizations andtherefore can be costly if there are many dependencies.• Each iteration involves a sparse least-squares solution with matrixwhere R T is the Cholesky factor of the preconditioner. Therefore, thereis a potential conflict between choosing an effective preconditionerand minimizing fill in .Medium-Scale <strong>Optimization</strong>Better numerical results are likely if you specify equalities explicitly,using Aeq and beq, instead of implicitly, using lb and ub.If equality constraints are present and dependent equalities aredetected and removed in the quadratic subproblem, 'dependent' isdisplayed under the Procedures heading (when you ask for outputby setting the Display option to'iter'). The dependent equalitiesare only removed when the equalities are consistent. If the systemof equalities is not consistent, the subproblem is infeasible and'infeasible' is displayed under the Procedures heading.AlgorithmLarge-Scale <strong>Optimization</strong>The large-scale algorithm is a subspace trust region method and isbased on the interior-reflective Newton method described in [1] and[2]. Each iteration involves the approximate solution of a large linearsystem using the method of preconditioned conjugate gradients (PCG).See the trust region and preconditioned conjugate gradient methoddescriptions in Chapter 4, “Large-Scale Algorithms”.Medium-Scale <strong>Optimization</strong>fmincon uses a sequential quadratic programming (SQP) method.In this method, the function solves a quadratic programming (QP)8-51

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