A note on fast approximate minimum degree orderings for symmetric matrices with some dense rows
نویسندگان
چکیده
Recently a number of variants of the approximate minimum degree algorithm have been proposed that aim to efficiently order symmetric matrices containing some dense rows. We compare the performance of these variants on a range of problems and highlight their limitations. This leads us to propose a new variant that offers both speed and robustness.
منابع مشابه
An approximate minimum degree algorithm for matrices with dense rows
We present a modified version of the approximate minimum degree algorithm for preordering a matrix with a symmetric sparsity pattern prior to the numerical factorization. The modification is designed to improve the efficiency of the algorithm when some of the rows and columns have significantly more entries than the average for the matrix. Numerical results are presented for problems arising fr...
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ورودعنوان ژورنال:
- Numerical Lin. Alg. with Applic.
دوره 17 شماره
صفحات -
تاریخ انتشار 2010