Block Algorithms for Orthogonal Symplectic Factorizations
نویسنده
چکیده
On the basis of a new WY -like representation block algorithms for orthogonal symplectic matrix factorizations are presented. Special emphasis is placed on symplectic QR and URV factorizations. The block variants mainly use level 3 (matrix-matrix) operations that permit data reuse in the higher levels of a memory hierarchy. Timing results show that our new algorithms outperform standard algorithms by a factor 3–4 for sufficiently large problems. AMS subject classification: 65F25, 15A23, 65P10, 65F15
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