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arXiv · 0901.3512

Seed methods for linear equations in lattice qcd problems with multiple right-hand sides

Abdou Abdel-Rehim·Ronald B. Morgan·Walter Wilcox
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Abstract

We consider three improvements to seed methods for Hermitian linear systems with multiple right-hand sides: only the Krylov subspace for the first system is used for seeding subsequent right-hand sides, the first right-hand side is solved past convergence, and periodic re-orthogonalization is used in order to control roundoff errors associated with the Conjugate Gradient algorithm. The method is tested for the case of Wilson fermions near kappa critical and a considerable speed up in the convergence is observed.

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Abdou Abdel-Rehim, Ronald B. Morgan, Walter Wilcox. 2009-02-26. Seed methods for linear equations in lattice qcd problems with multiple right-hand sides. https://arxiv.org/abs/0901.3512

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