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arXiv · 2101.12005

Multigrid as an exact solver

Adem Kaya
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Abstract

We provide an alternative Fourier analysis for multigrid applied to the Poisson problem in 1D, based on explicit derivation of spectra of the iteration matrix. The new Fourier analysis has advantages over the existing one. It is easy to understand and enables us to write the error equation in terms of the eigenvector of the stiffness matrix. When weighted-Jacobi is used as a smoother with two different weights, multigrid is an exact solver.

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Adem Kaya. 2021-01-21. Multigrid as an exact solver. https://arxiv.org/abs/2101.12005

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