A blocked QR-decomposition for the parallel symmetric eigenvalue problem
نویسندگان
چکیده
In this paper we present a new stable algorithm for the parallel QR-decomposition of ”tall and skinny” matrices. The algorithm has been developed for the dense symmetric eigensolver ELPA, whereat the QR-decomposition of tall and skinny matrices represents an important substep. Our new approach is based on the fast but unstable CholeskyQR algorithm [1]. We show the stability of our new algorithm and provide promising results of our MPI-based implementation on a BlueGene/P and a Power6 system.
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عنوان ژورنال:
- Parallel Computing
دوره 40 شماره
صفحات -
تاریخ انتشار 2014