RAL - TR - 2007 - 021 December 2007
نویسندگان
چکیده
Algebraic multigrid (AMG) is an efficient multilevel method for solving large sparse linear systems obtained from the discretisation of scalar elliptic partial differential equations. AMG can be used to compute powerful preconditioners for use with Krylov subspace methods. We report on the design and development of an efficient, robust and portable implementation of AMG that is available as package HSL MI20 within the HSL mathematical software library. HSL MI20 implements the classical (Ruge-Stüben) AMG method and, although it can be used as a “black-box” preconditioner, it offers the user a large number of options and parameters that may be tuned to enhance its performance for specific applications. The performance of HSL MI20 is illustrated using finite element discretisations of diffusion and convectiondiffusion problems in three dimensions.
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