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Solving the normal equations corresponding to large sparse linear least-squares problems is an important and challenging problem. For very large problems, an iterative solver is needed and, in general, a preconditioner is required to…

Numerical Analysis · Mathematics 2022-01-04 Hussam Al Daas , Pierre Jolivet , Jennifer Scott

This paper introduces a new preconditioning technique that is suitable for matrices arising from the discretization of a system of PDEs on unstructured grids. The preconditioner satisfies a so-called filtering property, which ensures that…

Numerical Analysis · Computer Science 2011-03-17 Laura Grigori , Frédéric Nataf

The goal of this paper is to propose preconditioners for the system of linear equations that arises from a discretization of fourth order elliptic problems using spectral element methods. These preconditioners are constructed using…

Numerical Analysis · Mathematics 2016-08-31 Akhlaq Husain , Arbaz Khan

This paper presents and studies an approach for constructing auxiliary space preconditioners for finite element problems using a constrained nonconforming reformulation, that is based on a proposed modified version of the mortar method. The…

Numerical Analysis · Mathematics 2020-10-09 Delyan Z. Kalchev , Panayot S. Vassilevski

The paper considers grad-div stabilized equal-order finite elements (FE) methods for the linearized Navier-Stokes equations. A block triangular preconditioner for the resulting system of algebraic equations is proposed which is closely…

Numerical Analysis · Mathematics 2024-11-12 Yunhui He , Maxim Olshanskii

In this paper we study how the use of a more continuous set of basis functions affects the cost of solving systems of linear equations resulting from a discretized Galerkin weak form. Specifically, we compare performance of linear solvers…

Numerical Analysis · Computer Science 2012-06-15 Nathan Collier , Lisandro Dalcin , David Pardo , V. M. Calo

We introduce a neural-preconditioned iterative solver for Poisson equations with mixed boundary conditions. Typical Poisson discretizations yield large, ill-conditioned linear systems. Iterative solvers can be effective for these problems,…

Numerical Analysis · Mathematics 2025-12-16 Kai Weixian Lan , Elias Gueidon , Ayano Kaneda , Julian Panetta , Joseph Teran

In this paper, we present block preconditioners for a stabilized discretization of the poroelastic equations developed in [45]. The discretization is proved to be well-posed with respect to the physical and discretization parameters, and…

Numerical Analysis · Mathematics 2020-01-07 James H. Adler , Francisco J. Gaspar , Xiaozhe Hu , Peter Ohm , Carmen Rodrigo , Ludmil T. Zikatanov

We apply preconditioning, which is widely used in classical solvers for linear systems $A\textbf{x}=\textbf{b}$, to the variational quantum linear solver. By utilizing incomplete LU factorization as a preconditioner for linear equations…

Several preconditioned AOR methods have been proposed to solve system of linear equations $Ax=b$, where $A \in \mathbb{R}^{n \times n}$ is a unit Z-matrix. The aim of this paper is to give a comparison result for a class of preconditioners…

Numerical Analysis · Mathematics 2014-04-09 Davod Khojasteh Salkuyeh , Mohsen Hasani , Fatemeh Panjeh Ali Beik

Given an ordered structure, we study a natural way to extend the order to preorders on type spaces. For definably complete, linearly ordered structures, we give a characterisation of the preorder on the space of 1-types. We apply these…

In this paper we design and analyze a uniform preconditioner for a class of high order Discontinuous Galerkin schemes. The preconditioner is based on a space splitting involving the high order conforming subspace and results from the…

Numerical Analysis · Mathematics 2014-12-03 Paola F. Antonietti , Marco Sarti , Marco Verani , Ludmil T. Zikatanov

In this paper we develop a family of preconditioners for the linear algebraic systems arising from the arbitrary Lagrangian-Eulerian discretization of some fluid-structure interaction models. After the time discretization, we formulate the…

Numerical Analysis · Mathematics 2023-07-19 Jinchao Xu , Kai Yang

The Sinc-Nystr\"{o}m method is a high-order numerical method based on Sinc basis functions for discretizing evolutionary differential equations in time. But in this method we have to solve all the time steps in one-shot (i.e. all-at-once),…

Numerical Analysis · Mathematics 2021-12-01 Jun Liu , Shu-Lin Wu

A uniform inf-sup condition related to a parameter dependent Stokes problem is established. Such conditions are intimately connected to the construction of uniform preconditioners for the problem, i.e., preconditioners which behave…

Numerical Analysis · Mathematics 2012-01-10 Kent-Andre Mardal , Joachim Schöberl , Ragnar Winther

In this paper, we consider the composite optimization problem, where the objective function integrates a continuously differentiable loss function with a nonsmooth regularization term. Moreover, only the function values for the…

Optimization and Control · Mathematics 2024-01-09 Shanglin Liu , Lei Wang , Nachuan Xiao , Xin Liu

The efficient solution of discretisations of coupled systems of partial differential equations (PDEs) is at the core of much of numerical simulation. Significant effort has been expended on scalable algorithms to precondition Krylov…

Mathematical Software · Computer Science 2018-02-22 Robert C. Kirby , Lawrence Mitchell

We consider the minimization problem with the truncated quadratic regularization with gradient operator, which is a nonsmooth and nonconvex problem. We cooperated the classical preconditioned iterations for linear equations into the…

Optimization and Control · Mathematics 2021-05-04 Shengxiang Deng , Hongpeng Sun

Preconditioning of a linear system obtained from spectral discretization of time-dependent PDEs often results in a full matrix which is expensive to compute and store specially when the problem size increases. A matrix-free implementation…

Statistics Theory · Mathematics 2016-06-09 A. Ghasemi , L. K. Taylor

In this paper we study the linear systems arising from discretized poroelasticity problems. We formulate one block preconditioner for the two-filed Biot model and several preconditioners for the classical three-filed Biot model under the…

Numerical Analysis · Mathematics 2020-07-15 Shuangshuang Chen , Qingguo Hong , Jinchao Xu , Kai Yang