Results 11 to 20 of about 713 (182)
Weighted Inner Products for GMRES and GMRES-DR [PDF]
Revision containing edits to the text, corrections, and removal of the section on Arnoldi in weighted inner products (to reduce the manuscript's length)
Embree, Mark +2 more
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The GMRES algorithm of Saad and Schultz (1986) is an iterative method for approximately solving linear systems $A{\bf x}={\bf b}$, with initial guess ${\bf x}_0$ and residual ${\bf r}_0 = {\bf b} - A{\bf x}_0$. The algorithm employs the Arnoldi process to generate the Krylov basis vectors (the columns of $V_k$).
Stephen Thomas +4 more
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Toward efficient polynomial preconditioning for GMRES [PDF]
AbstractWe present a polynomial preconditioner for solving large systems of linear equations. The polynomial is derived from the minimum residual polynomial (the GMRES polynomial) and is more straightforward to compute and implement than many previous polynomial preconditioners. Our current implementation of this polynomial using its roots is naturally
Jennifer A. Loe, Ronald B. Morgan
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GMRES and Integral Operators [PDF]
The purpose of this paper is to show how the generalized minimal residual (GMRES) method can be modified to incorporate Nyström interpolation at a small cost in both computational effort and algorithmic complexity. The result is an algorithm that has the convergence property of Broyden's method.
Kelley, C. T., Xue, Z. Q.
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Multipreconditioned Gmres for Shifted Systems [PDF]
An implementation of GMRES with multiple preconditioners (MPGMRES) is proposed for solving shifted linear systems with shift-and-invert preconditioners. With this type of preconditioner, the Krylov subspace can be built without requiring the matrix-vector product with the shifted matrix.
Bakhos, T. +4 more
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Adaptive version of Simpler GMRES [PDF]
The authors propose and theoretically analyze a stable version of simpler generalized minimal residual (GMRES) algorithm, based on an adaptive choice of the Krylov subspace basis at a given iteration step. They show that this adaptive choice of direction vectors keeps the basis well-conditioned and that the condition number grows at most linearly with ...
Jiránek, P., Rozložník, M. (Miroslav)
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Properties of Worst-Case GMRES [PDF]
In the convergence analysis of the GMRES method for a given matrix $A$, one quantity of interest is the largest possible residual norm that can be attained, at a given iteration step $k$, over all unit norm initial vectors. This quantity is called the worst-case GMRES residual norm for $A$ and $k$.
Faber, Vance +2 more
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In their introduction, the authors state, ``We study an oddity: the class of problems for which the generalized minimal residual (GMRES) algorithm, when started with the initial guess \(x^{(0)}=0\) and using exact arithmetic, computes \(m\) iterates \(x^{(1)}=\cdots=x^{(m)}=0\) without making any progress at all.
Zavorin, Ilya +2 more
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DAPHNE-3D: A NEW TRANSPORT SOLVER FOR UNSTRUCTURED TETRAHEDRAL MESHES [PDF]
A new Discrete Ordinates transport solver for unstructured tetrahedral meshes is presented. The solver uses the Discontinuous Galërkin Finite Element Method with linear or quadratic expansion of the flux within each cell.
Diamantopoulou Evangelia +1 more
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A relaxed block splitting preconditioner for complex symmetric indefinite linear systems
In this paper, we propose a relaxed block splitting preconditioner for a class of complex symmetric indefinite linear systems to accelerate the convergence rate of the Krylov subspace iteration method and the relaxed preconditioner is much closer to the ...
Huang Yunying, Chen Guoliang
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