Istituto di Scienza e Tecnologie dell'Informazione     
Arioli M., Duff I., Gould N., Reid J. Use of the P(4) and P(5) algorithms for in-core factorization of sparse matrices. Lavoro svolto presso la Computer Sciences Systems Division, Harwell Laboratory. Internal note IEI-B4-60, 1989.
We consider variants of the P∆4 algorithm of Hel1erman and Rarick and the P∆5 algorithm of Erisman, Grimes, Lewis and Poole, as used for generating a bordered block triangular form for the in-core solution of sparse sets of linear equations. We are particularly concerned with maintaining numerical stability and discuss methods for doing this and the extra cast that it entails. We also examine different factorization schemes, consider the use of matrix modification and iterative refinement, and compare the best variant with an established code for the solution of unsymmetric sparse sets of linear equations. We find that the established code is usualiy the most effective method.

Icona documento 1) Download Document PDF

Icona documento Open access Icona documento Restricted Icona documento Private


Per ulteriori informazioni, contattare: Librarian http://puma.isti.cnr.it

Valid HTML 4.0 Transitional