A Note on Preconditioning by Low-Stretch Spanning Trees
نویسندگان
چکیده
Boman and Hendrickson [BH01] observed that one can solve linear systems in Laplacian matrices in time O ( m ln(1/ǫ) ) by preconditioning with the Laplacian of a low-stretch spanning tree. By examining the distribution of eigenvalues of the preconditioned linear system, we prove that the preconditioned conjugate gradient will actually solve the linear system in time Õ ( m ln(1/ǫ) ) .
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ورودعنوان ژورنال:
- CoRR
دوره abs/0903.2816 شماره
صفحات -
تاریخ انتشار 2009