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arXiv · 2403.14961

Anderson Acceleration with Truncated Gram-Schmidt

Ziyuan Tang·Tianshi Xu·Huan He·Yousef Saad·Yuanzhe Xi
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Abstract

Anderson Acceleration (AA) is a popular algorithm designed to enhance the convergence of fixed-point iterations. In this paper, we introduce a variant of AA based on a Truncated Gram-Schmidt process (AATGS) which has a few advantages over the classical AA. In particular, an attractive feature of AATGS is that its iterates obey a three-term recurrence in the situation when it is applied to solving symmetric linear problems and this can lead to a considerable reduction of memory and computational costs. We analyze the convergence of AATGS in both full-depth and limited-depth scenarios and establish its equivalence to the classical AA in the linear case. We also report on the effectiveness of AATGS through a set of numerical experiments, ranging from solving nonlinear partial differential equations to tackling nonlinear optimization problems. In particular, the performance of the method is compared with that of the classical AA algorithms.

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Ziyuan Tang, Tianshi Xu, Huan He, Yousef Saad, Yuanzhe Xi. 2024-03-22. Anderson Acceleration with Truncated Gram-Schmidt. https://arxiv.org/abs/2403.14961

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