Results 221 to 230 of about 1,263 (265)
Some of the next articles are maybe not open access.

SOR as a Preconditioner

Applied Numerical Mathematics, 2017
Preconditioning is usually necessary for CG-type iterative algorithms for the solution of large sparse nonsymmetric linear systems. However, many good preconditioners have only marginal intrinsic parallelism -- ILU and SSOR in the natural ordering are essentially sequential algorithms.
DeLong, M. A., Ortega, J. M.
openaire   +3 more sources

A Schwarz Preconditioner for the Cubed-Sphere

SIAM Journal on Scientific Computing, 2003
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Stephen J. Thomas   +3 more
openaire   +2 more sources

Some Remarks on a Multigrid Preconditioner

SIAM Journal on Scientific Computing, 1994
A class of multilevel preconditioners is studied. A simple proof for optimal estimate of conditioning is given. Numerical examples are presented.
Jinchao Xu, Jinshui Qin
openaire   +2 more sources

Preconditioners for block Toeplitz systems based on circulant preconditioners

Numerical Algorithms, 2001
The numerical solution of block Toeplitz systems by preconditioned conjugate gradient methods is considered. Two types of preconditioners based on circulant preconditioners are proposed by combining the ideas which are used in the construction of circulant preconditioners with Toeplitz-like preconditioners.
openaire   +2 more sources

An approximate BDDC preconditioner

Numerical Linear Algebra with Applications, 2007
AbstractThe balancing domain decomposition by constraints (BDDC) preconditioner requires direct solutions of two linear systems for each substructure and one linear system for a global coarse problem. The computations and memory needed for these solutions can be prohibitive if any one system is too large.
openaire   +1 more source

On Inexact Preconditioners for Nonsymmetric Matrices

SIAM Journal on Scientific Computing, 2005
Summary: Inexact versions of the block-triangular preconditioners for nonsymmetric matrices of block two-by-two structures presented by \textit{M. F. Murphy, G. H. Golub}, and \textit{A. J. Wathen}[SIAM J. Sci. Comput. 21, No.~6, 1969--1972 (2000; Zbl 0959.65063)] and by \textit{I. C. F. Ipsen} [ibid.
Zhong-Zhi Bai, Michael K. Ng 0001
openaire   +1 more source

Multiresolution Approximate Inverse Preconditioners

SIAM Journal on Scientific Computing, 2001
Summary: We introduce a new preconditioner for elliptic partial differential equations (PDEs) on unstructured meshes. Using a wavelet-inspired basis we compress the inverse of the matrix, allowing an effective sparse approximate inverse by solving the sparsity vs. accuracy conflict. The key issue in this compression is to use second generation wavelets
Robert Bridson, Wei-Pai Tang
openaire   +2 more sources

Some Aspects of Circulant Preconditioners

SIAM Journal on Scientific Computing, 1993
If \(T\) is a given \(n\times n\) Hermitian Toeplitz matrix, the circulant matrix \(C_ 0\) is determined which minimizes \(\| I-C^{-1/2}TC^{- 1/2}\|_ F\) among all circulant matrices \(C\). It is shown that \(C_ 0\) can be computed in \(O(n\log n)\) operations and that the eigenvalues of \(C_ 0^ 1T\) are asymptotically clustered around \(z=1\).
openaire   +2 more sources

Design of a Library of Parallel Preconditioners

The International Journal of High Performance Computing Applications, 2000
The authors outline the design principles underlying the ParPre library of parallel preconditioners. ParPre is a message-passing library of distributed preconditioners for linear systems, written using MPI and Petsc. It comprises Schwarz methods, Schur system domain decompositioning, various parallel incomplete factorizations, and multilevel methods.
Tony F. Chan, Victor Eijkhout
openaire   +2 more sources

M-preconditioner for M-matrices

Applied Mathematics and Computation, 2006
The paper deals with the development and analysis of a preconditioner for the conjugate gradient approach to symmetric linear algebraic systems with a nonsingular \(M\)-matrix as coefficient matrix. Numerical results illustrate the convergence behavior of the new preconditioned conjugate gradient method.
openaire   +2 more sources

Home - About - Disclaimer - Privacy