Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

On Compatible Transfer Operators in Nonsymmetric Algebraic Multigrid

Journal Article · · SIAM Journal on Matrix Analysis and Applications
DOI:https://doi.org/10.1137/23m1586069· OSTI ID:2433953
 [1];  [2]
  1. Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
  2. Univ. of Colorado, Boulder, CO (United States)
The standard goal for an effective algebraic multigrid (AMG) algorithm is to develop relaxation and coarse-grid correction schemes that attenuate complementary error modes. In the nonsymmetric setting, coarse-grid correction Π will almost certainly be nonorthogonal (and divergent) in any known standard product, meaning ∥Π∥ > 1. This introduces a new consideration, that one wants coarse-grid correction to be as close to orthogonal as possible, in an appropriate norm. In addition, due to nonorthogonality, Π may actually amplify certain error modes that are in the range of interpolation. Relaxation must then not only be complementary to interpolation, but also rapidly eliminate any error amplified by the nonorthogonal correction, or the algorithm may diverge. Here this paper develops analytic formulae on how to construct “compatible” transfer operators in nonsymmetric AMG such that ∥Π∥ = 1 in some standard matrix-induced norm. Discussion is provided on different options for the norm in the nonsymmetric setting, the relation between “ideal” transfer operators in different norms, and insight into the convergence of nonsymmetric reduction-based AMG.
Research Organization:
Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
Sponsoring Organization:
USDOE Laboratory Directed Research and Development (LDRD) Program; USDOE National Nuclear Security Administration (NNSA)
Grant/Contract Number:
89233218CNA000001
OSTI ID:
2433953
Report Number(s):
LA-UR--23-26552
Journal Information:
SIAM Journal on Matrix Analysis and Applications, Journal Name: SIAM Journal on Matrix Analysis and Applications Journal Issue: 3 Vol. 45; ISSN 0895-4798
Publisher:
Society for Industrial and Applied Mathematics (SIAM)Copyright Statement
Country of Publication:
United States
Language:
English

References (14)

A robust algebraic multilevel preconditioner for non-symmetricM-matrices journal January 2000
Multigrid transfers for nonsymmetric systems based on Schur complements and Galerkin projections: SCHUR COMPLEMENT-BASED MULTIGRID TRANSFERS journal June 2013
Coarsening by compatible relaxation journal March 2004
On two-grid convergence estimates
  • Falgout, Robert D.; Vassilevski, Panayot S.; Zikatanov, Ludmil T.
  • Numerical Linear Algebra with Applications, Vol. 12, Issue 5-6 https://doi.org/10.1002/nla.437
journal January 2005
Algebraic analysis of two‐grid methods: The nonsymmetric case journal April 2009
The many proofs of an identity on the norm of oblique projections journal October 2006
A New Petrov–Galerkin Smoothed Aggregation Preconditioner for Nonsymmetric Linear Systems journal January 2008
Towards Adaptive Smoothed Aggregation ($\alpha$SA) for Nonsymmetric Problems journal January 2010
Compatible Relaxation and Coarsening in Algebraic Multigrid journal January 2010
A Root-Node--Based Algebraic Multigrid Method journal January 2017
Optimal Interpolation and Compatible Relaxation in Classical Algebraic Multigrid journal January 2018
Nonsymmetric Algebraic Multigrid Based on Local Approximate Ideal Restriction ($\ell$AIR) journal January 2018
Nonsymmetric Reduction-Based Algebraic Multigrid journal January 2019
Convergence in Norm of Nonsymmetric Algebraic Multigrid journal January 2019

Similar Records

Compatible Relaxation and Coarsening in Algebraic Multigrid
Journal Article · Tue Sep 22 00:00:00 EDT 2009 · SIAM Journal on Scientific Computing · OSTI ID:985488

Reducing Parallel Communication in Algebraic Multigrid through Sparsification
Journal Article · Thu Dec 31 19:00:00 EST 2015 · SIAM Journal on Scientific Computing · OSTI ID:1808755

Distance-Two Interpolation for Parallel Algebraic Multigrid
Journal Article · Tue May 08 00:00:00 EDT 2007 · Numerical Linear Algebra with Applications, vol. 15, no. 2-3, December 3, 2007, pp. 115-139 · OSTI ID:940875