ilu and iul factorizations obtained from forward and backward factored approximate inverse algorithms

نویسندگان

a. rafiei

چکیده

in this paper‎, ‎an efficient dropping criterion has been used to compute the iul factorization obtained from backward factored approximate inverse (bfapinv) and ilu factorization obtained from forward factored approximate inverse (ffapinv) algorithms‎. ‎we use different drop tolerance parameters to compute the preconditioners‎. ‎to study the effect of such a dropping on the quality of the ilu and iul factorizations‎, ‎we have used the preconditioners as the right preconditioners for several linear systems and then‎, ‎the krylov subspace methods have been used to solve the preconditioned systems‎. ‎to avoid storing matrix $a$ in two csr and csc formats‎, ‎the linked lists trick has been used in the implementations‎. ‎as the preprocessing‎, ‎the multilevel nested dissection reordering has also been used‎.

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عنوان ژورنال:
bulletin of the iranian mathematical society

ناشر: iranian mathematical society (ims)

ISSN 1017-060X

دوره 40

شماره 5 2014

میزبانی شده توسط پلتفرم ابری doprax.com

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