Scalable Derivative-Free Optimization Algorithms with Low-Dimensional Subspace Techniques

Zaikun Zhang

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arXiv · 2501.04536

Scalable Derivative-Free Optimization Algorithms with Low-Dimensional Subspace Techniques

Zaikun Zhang

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Abstract

We re-introduce a derivative-free subspace optimization framework originating from Chapter 5 of the Ph.D. thesis [Z. Zhang, On Derivative-Free Optimization Methods, Ph.D. thesis, Chinese Academy of Sciences, Beijing, 2012] of the author under the supervision of Ya-xiang Yuan. At each iteration, the framework defines a (low-dimensional) subspace based on an approximate gradient, and then solves a subproblem in this subspace to generate a new iterate. We sketch the global convergence and worst-case complexity analysis of the framework, elaborate on its implementation, and present some numerical results on solving problems with dimensions as high as 10^4 using only inaccurate function values.

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Zaikun Zhang. 2025-01-08. Scalable Derivative-Free Optimization Algorithms with Low-Dimensional Subspace Techniques. https://arxiv.org/abs/2501.04536

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