Block and Parallel Versions of One-Sided Bidiagonalization
نویسندگان
چکیده
Two new algorithms for one-sided bidiagonalization are presented. The first is a block version which improves execution time by improving cache utilization from the use of BLAS 2.5 operations and more BLAS 3 operations. The second is adapted to parallel computation. When incorporated into singular value decomposition software, the second algorithm is faster than the corresponding ScaLAPACK routine in most cases. An error analysis is presented for the first algorithm. Numerical results and timings are presented for both algorithms.
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ورودعنوان ژورنال:
- SIAM J. Matrix Analysis Applications
دوره 29 شماره
صفحات -
تاریخ انتشار 2007