Results 221 to 230 of about 625 (264)
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Preconditioners for block Toeplitz systems based on circulant preconditioners
Numerical Algorithms, 2001The 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.
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Applied Numerical Mathematics, 1995
The paper contains numerical results concerning the use of successive overrelaxation (SOR) as a preconditioner for the nonsymmetric iterative solvers GMRES and BiCGSTAB. As a test example, the authors choose a 2D convection-diffusion equation on the unit square with Dirichlet boundary conditions discretized by standard five-point finite differences for
DeLong, M. A., Ortega, J. M.
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The paper contains numerical results concerning the use of successive overrelaxation (SOR) as a preconditioner for the nonsymmetric iterative solvers GMRES and BiCGSTAB. As a test example, the authors choose a 2D convection-diffusion equation on the unit square with Dirichlet boundary conditions discretized by standard five-point finite differences for
DeLong, M. A., Ortega, J. M.
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Maximum-weight-basis preconditioners
Numerical Linear Algebra With Applications, 2004AbstractThis paper analyses a novel method for constructing preconditioners for diagonally dominant symmetric positive‐definite matrices. The method discussed here is based on a simple idea: we construct M by simply dropping offdiagonal non‐zeros from A and modifying the diagonal elements to maintain a certain row‐sum property.
Sivan Toledo +2 more
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A Schwarz Preconditioner for the Cubed-Sphere
SIAM Journal on Scientific Computing, 2003zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Stephen J. Thomas +3 more
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An approximate BDDC preconditioner
Numerical Linear Algebra with Applications, 2007AbstractThe 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.
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Some Remarks on a Multigrid Preconditioner
SIAM Journal on Scientific Computing, 1994A class of multilevel preconditioners is studied. A simple proof for optimal estimate of conditioning is given. Numerical examples are presented.
Jinchao Xu, Jinshui Qin
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Multiresolution Approximate Inverse Preconditioners
SIAM Journal on Scientific Computing, 2001Summary: 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
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Optimal and Superoptimal Circulant Preconditioners
SIAM Journal on Matrix Analysis and Applications, 1992The author investigates preconditioning methods for linear algebraic systems \(Ax=f\) with a dense positive definite matrix \(A\). He calls a conditioning matrix \(C\) optimal if it minimizes \(\| C-A\|\) and superoptimal if it minimizes \(\| I-C^{-1} A\|\), both in the Frobenius norm.
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M-preconditioner for M-matrices
Applied Mathematics and Computation, 2006The 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.
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Design of a Library of Parallel Preconditioners
The International Journal of High Performance Computing Applications, 2000The 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
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