For more information about this meeting, contact Xiantao Li.
|Title:||Krylov Methods and Energy Minimization Algebraic Multigrid|
|Seminar:||CCMA Luncheon Seminar|
|Speaker:||Ray Tuminaro, Sandia National Lab|
|A general interpolation strategy for algebraic multigrid that employs an energy-minimization principle is presented.
We describe how Krylov minimization ideas can be used to generate prolongators and restrictors for symmetric and
nonsymmetric problems. It is well known that Krylov methods minimize error in some norm when they are applied to the
solution of linear systems. This same minimization property can be employed to apply a Krylov method to obtain grid
transfer operators as opposed to the solution of linear systems. We illustrate how this leads to a class of fairly
general methods for constructing grid transfers.
An advantage of energy-minimization approaches is that they are quite flexible. In particular, it is relatively
straight-forward to use energy-minimization with a variety of coarsening schemes and prolongator/restrictor sparsity
patterns. A new algebraic multigrid software framework is described that attempts to capture this flexibility
and provide a fairly general tool that can be used to develop new multigrid schemes. A number of important practical
aspects of energy minimization algebraic multigrid are discussed including: linear dependency issues among
prolongator columns and the cost of prolongator construction.|
Room Reservation Information
|Date:||03 / 04 / 2011|
|Time:||12:15pm - 01:30pm|