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arXiv · 1506.06829

Generalized preconditioned locally harmonic residual method for non-Hermitian eigenproblems

Eugene Vecharynski·Chao Yang·Fei Xue
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Abstract

We introduce the Generalized Preconditioned Locally Harmonic Residual (GPLHR) method for solving standard and generalized non-Hermitian eigenproblems. The method is particularly useful for computing a subset of eigenvalues, and their eigen- or Schur vectors, closest to a given shift. The proposed method is based on block iterations and can take advantage of a preconditioner if it is available. It does not need to perform exact shift-and-invert transformation. Standard and generalized eigenproblems are handled in a unified framework. Our numerical experiments demonstrate that GPLHR is generally more robust and efficient than existing methods, especially if the available memory is limited.

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Eugene Vecharynski, Chao Yang, Fei Xue. 2015-06-23. Generalized preconditioned locally harmonic residual method for non-Hermitian eigenproblems. https://arxiv.org/abs/1506.06829

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