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arXiv · 2401.03565

An Inexact Preconditioned Zeroth-order Proximal Method for Composite Optimization

Shanglin Liu·Lei Wang·Nachuan Xiao·Xin Liu
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Abstract

In this paper, we consider the composite optimization problem, where the objective function integrates a continuously differentiable loss function with a nonsmooth regularization term. Moreover, only the function values for the differentiable part of the objective function are available. To efficiently solve this composite optimization problem, we propose a preconditioned zeroth-order proximal gradient method in which the gradients and preconditioners are estimated by finite-difference schemes based on the function values at the same trial points. We establish the global convergence and worst-case complexity for our proposed method. Numerical experiments exhibit the superiority of our developed method.

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Shanglin Liu, Lei Wang, Nachuan Xiao, Xin Liu. 2024-01-07. An Inexact Preconditioned Zeroth-order Proximal Method for Composite Optimization. https://arxiv.org/abs/2401.03565

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