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arXiv · 1201.5055

Structure-preserving Schur methods for computing square roots of real skew-Hamiltonian matrices

Zhongyun Liu·Yulin Zhang·Carla Ferreira·Rui Ralha
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Abstract

Our contribution is two-folded. First, starting from the known fact that every real skew-Hamiltonian matrix has a real Hamiltonian square root, we give a complete characterization of the square roots of a real skew-Hamiltonian matrix W. Second, we propose a structure exploiting method for computing square roots of W. Compared to the standard real Schur method, which ignores the structure, our method requires significantly less arithmetic.

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Zhongyun Liu, Yulin Zhang, Carla Ferreira, Rui Ralha. 2012-01-24. Structure-preserving Schur methods for computing square roots of real skew-Hamiltonian matrices. https://arxiv.org/abs/1201.5055

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