English
Related papers

Related papers: Block CG algorithms revisited

200 papers

Various recurrence relations between formal orthogonal polynomials can be used to derive Lanczos-type algorithms. In this paper, we consider recurrence relation $A_{12}$ for the choice $U_i(x)=P_i(x)$, where $U_i$ is an auxiliary family of…

Numerical Analysis · Mathematics 2014-05-08 Saif Ullah , Muhammad Farooq , Abdellah Salhi

We analyse the convergence of the proximal gradient algorithm for convex composite problems in the presence of gradient and proximal computational inaccuracies. We derive new tighter deterministic and probabilistic bounds that we use to…

Optimization and Control · Mathematics 2022-03-07 Anis Hamadouche , Yun Wu , Andrew M. Wallace , Joao F. C. Mota

Using lower precision in algorithms can be beneficial in terms of reducing both computation and communication costs. Motivated by this, we aim to further the state-of-the-art in developing and analyzing mixed precision variants of iterative…

Numerical Analysis · Mathematics 2022-10-18 Eda Oktay , Erin Carson

We analyze the convergence of the Conjugate Gradient (CG) method in exact arithmetic, when the coefficient matrix $A$ is symmetric positive semidefinite and the system is consistent. To do so, we diagonalize $A$ and decompose the algorithm…

Numerical Analysis · Mathematics 2020-05-12 Ken Hayami

We propose an adaptive mixed precision and dynamically scaled preconditioned conjugate gradient algorithm (AMP-PCG). It dynamically adjusts the precision for storing vectors and computing, exploiting low precision when appropriate, while…

Numerical Analysis · Mathematics 2025-05-08 Yichen Guo , Eric de Sturler , Tim Warburton

Block-coordinate algorithms are recognized to furnish efficient iterative schemes for addressing large-scale problems, especially when the computation of full derivatives entails substantial memory requirements and computational efforts. In…

Optimization and Control · Mathematics 2025-04-16 Pedro Pérez-Aros , David Torregrosa-Belén

This paper expands the Cyclic Block Proximal Gradient method for block separable composite minimization by allowing for inexactly computed gradients and proximal maps. The resultant algorithm, the Inexact Cyclic Block Proximal Gradient…

Optimization and Control · Mathematics 2022-01-05 Leandro Maia , David Huckleberry Gutman , Ryan Christopher Hughes

Due to their flexibility and theoretical tractability Gaussian process (GP) regression models have become a central topic in modern statistics and machine learning. While the true posterior in these models is given explicitly, numerical…

Machine Learning · Statistics 2024-06-19 Bernhard Stankewitz , Botond Szabo

The conjugate gradient method is a widely used algorithm for the numerical solution of a system of linear equations. It is particularly attractive because it allows one to take advantage of sparse matrices and produces (in case of infinite…

Numerical Analysis · Mathematics 2017-11-27 Sergey Voronin , Christophe Zaroli , Naresh P. Cuntoor

This paper proposes a generalization of the conjugate gradient (CG) method used to solve the equation $Ax=b$ for a symmetric positive definite matrix $A$ of large size $n$. The generalization consists of permitting the scalar control…

Numerical Analysis · Mathematics 2016-11-17 Amit Bhaya , Pierre-Alexandre Bliman , Guilherme Niedu , Fernando Pazos

Recent years have witnessed the rapid development of block coordinate update (BCU) methods, which are particularly suitable for problems involving large-sized data and/or variables. In optimization, BCU first appears as the coordinate…

Optimization and Control · Mathematics 2018-01-04 Yangyang Xu

We study the iterative solution of linear systems of equations arising from stochastic Galerkin finite element discretizations of saddle point problems. We focus on the Stokes model with random data parametrized by uniformly distributed…

Numerical Analysis · Mathematics 2018-10-31 Christopher Müller , Sebastian Ullmann , Jens Lang

Cyclic block coordinate methods are a fundamental class of optimization methods widely used in practice and implemented as part of standard software packages for statistical learning. Nevertheless, their convergence is generally not well…

Optimization and Control · Mathematics 2023-06-09 Chaobing Song , Jelena Diakonikolas

We present two open-source implementations of the Locally Optimal Block Preconditioned Conjugate Gradient (LOBPCG) algorithm to find a few eigenvalues and eigenvectors of large, possibly sparse matrices. We then test LOBPCG for various…

Numerical Analysis · Mathematics 2023-05-12 Tommaso Nottoli , Ivan Giannì , Antoine Levitt , Filippo Lipparini

The increasing imbalance between the computing capabilities of individual nodes and the internode bandwidth makes it highly desirable for any Lattice QCD algorithm to minimize the amount of internode communication. One of the relatively new…

High Energy Physics - Lattice · Physics 2019-01-09 Yong-Chull Jang , Chulwoo Jung

The performance of eigenvalue problem solvers (eigensolvers) depends on various factors such as preconditioning and eigenvalue distribution. Developing stable and rapidly converging vectorwise eigensolvers is a crucial step in improving the…

Numerical Analysis · Mathematics 2026-01-09 Ming Zhou , Klaus Neymeyr

We present an iterative algorithm for computing an invariant subspace associated with the algebraically smallest eigenvalues of a large sparse or structured Hermitian matrix A. We are interested in the case in which the dimension of the…

Numerical Analysis · Mathematics 2015-06-22 Eugene Vecharynski , Chao Yang , John E. Pask

The efficient solution of large-scale multiterm linear matrix equations is a challenging task in numerical linear algebra, and it is a largely open problem. We propose a new iterative scheme for symmetric and positive definite operators,…

Numerical Analysis · Mathematics 2025-05-27 Davide Palitta , Martina Iannacito , Valeria Simoncini

The method of block coordinate gradient descent (BCD) has been a powerful method for large-scale optimization. This paper considers the BCD method that successively updates a series of blocks selected according to a Markov chain. This kind…

Optimization and Control · Mathematics 2018-11-26 Tao Sun , Yuejiao Sun , Yangyang Xu , Wotao Yin

Tuning scientific and probabilistic machine learning models $-$ for example, partial differential equations, Gaussian processes, or Bayesian neural networks $-$ often relies on evaluating functions of matrices whose size grows with the data…

Machine Learning · Computer Science 2024-10-28 Nicholas Krämer , Pablo Moreno-Muñoz , Hrittik Roy , Søren Hauberg