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Related papers: A federated Kaczmarz algorithm

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This paper investigates the randomized version of the Kaczmarz method to solve linear systems in the case where the adjoint of the system matrix is not exact---a situation we refer to as "mismatched adjoint". We show that the method may…

Numerical Analysis · Mathematics 2018-03-09 Dirk A. Lorenz , Sean Rose , Frank Schöpfer

The Kaczmarz method for solving a linear system $Ax = b$ interprets such a system as a collection of equations $\left\langle a_i, x\right\rangle = b_i$, where $a_i$ is the $i-$th row of $A$, then picks such an equation and corrects $x_{k+1}…

Numerical Analysis · Mathematics 2021-09-15 Stefan Steinerberger

The randomized Kaczmarz ($\RK$) algorithm is a simple but powerful approach for solving consistent linear systems $Ax=b$. This paper proposes an accelerated randomized Kaczmarz ($\ARK$) algorithm with better convergence than the standard…

Numerical Analysis · Mathematics 2014-06-10 Ji Liu , Stephen J. Wright

The Kaczmarz algorithm is a well known iterative method for solving overdetermined linear systems. Its randomized version yields provably exponential convergence in expectation. In this paper, we propose two new methods to speed up the…

Numerical Analysis · Computer Science 2016-08-02 Tengfei Ma

We establish an improved classical algorithm for solving linear systems in a model analogous to the QRAM that is used by quantum linear solvers. Precisely, for the linear system $A\x = \b$, we show that there is a classical algorithm that…

Quantum Physics · Physics 2023-04-18 Changpeng Shao , Ashley Montanaro

In this paper, an extension of Kaczmarz method, the Kaczmarz method with oblique projection (KO), is introduced and analyzed. Using this method, a number of iteration steps to solve the over-determined systems of linear equations are…

Numerical Analysis · Mathematics 2021-06-28 Weiguo Li , Qifeng Wang , Wendi Bao , Li Liu

The randomized extended Kaczmarz and Gauss-Seidel algorithms have attracted much attention because of their ability to treat all types of linear systems (consistent or inconsistent, full rank or rank-deficient). In this paper, we interpret…

Numerical Analysis · Mathematics 2018-01-11 Kui Du

We present a randomized iterative algorithm that exponentially converges in expectation to the minimum Euclidean norm least squares solution of a given linear system of equations. The expected number of arithmetic operations required to…

Numerical Analysis · Mathematics 2018-07-24 Anastasios Zouzias , Nikolaos Freris

The Kaczmarz method is an iterative method for solving large systems of equations that projects iterates orthogonally onto the solution space of each equation. In contrast to direct methods such as Gaussian elimination or QR-factorization,…

Numerical Analysis · Computer Science 2013-09-30 Noreen Jamil , Deanna Needell , Johannes Muller , Christof Lutteroth , Gerald Weber

A greedy randomized augmented Kaczmarz (GRAK) method was proposed in [Z.-Z. Bai and W.-T. WU, SIAM J. Sci. Comput., 43 (2021), pp. A3892-A3911] for large and sparse inconsistent linear systems. However, one has to construct two new index…

Numerical Analysis · Mathematics 2023-10-24 Shunchang Li , Gang Wu

To efficiently solve large scale nonlinear systems, we propose a novel Random Greedy Fast Block Kaczmarz method. This approach integrates the strengths of random and greedy strategies while avoiding the computationally expensive…

Numerical Analysis · Mathematics 2025-08-14 Renjie Ding , Dongling Wang

The Extended Randomized Kaczmarz method is a well known iterative scheme which can find the Moore-Penrose inverse solution of a possibly inconsistent linear system and requires only one additional column of the system matrix in each…

Numerical Analysis · Mathematics 2022-07-21 Frank Schöpfer , Dirk A Lorenz , Lionel Tondji , Maximilian Winkler

We develop a novel, fundamental and surprisingly simple randomized iterative method for solving consistent linear systems. Our method has six different but equivalent interpretations: sketch-and-project, constrain-and-approximate, random…

Numerical Analysis · Mathematics 2016-01-07 Robert M. Gower , Peter Richtárik

The block Kaczmarz method is an iterative scheme for solving overdetermined least-squares problems. At each step, the algorithm projects the current iterate onto the solution space of a subset of the constraints. This paper describes a…

Numerical Analysis · Mathematics 2015-03-20 Deanna Needell , Joel A. Tropp

The Kaczmarz method is an iterative projection scheme for solving con-sistent system $Ax = b$. It is later extended to the inconsistent and ill-posed linear problems. But the classical Kaczmarz method is sensitive to the correlation of the…

Numerical Analysis · Mathematics 2022-10-04 Chuan-gang Kang , Heng Zhou

The generalized Gearhart-Koshy acceleration is a recent exact affine search technique designed for the method of cyclic projections onto hyperplanes, i.e., the Kaczmarz method. However, its convergence properties, particularly the linear…

Numerical Analysis · Mathematics 2026-04-08 Yijie Wang , Yonghan Sun , Deren Han , Jiaxin Xie

The Kaczmarz method is an efficient iterative algorithm for large-scale linear systems. However, its linear convergence rate suffers from ill-conditioned problems and is highly sensitive to the smallest nonzero singular value. In this work,…

Numerical Analysis · Mathematics 2026-02-26 Yunying Ke , Hao Luo

The Kaczmarz algorithm (KA) is a popular method for solving a system of linear equations. In this note we derive a new exponential convergence result for the KA. The key allowing us to establish the new result is to rewrite the KA in such a…

Systems and Control · Computer Science 2015-06-23 Liang Dai , Thomas Schön

In this paper, we consider a novel two-dimensional randomized Kaczmarz method and its improved version with simple random sampling, which chooses two active rows with probability proportional to the square of their cross-product-like…

Numerical Analysis · Mathematics 2025-06-27 Tao Li , Meng-Long Xiao , Xin-Fang Zhang

We develop a stochastic approximation version of the classical Kaczmarz algorithm that is incremental in nature and takes as input noisy real time data. Our analysis shows that with probability one it mimics the behavior of the original…

Optimization and Control · Mathematics 2014-04-29 Gugan Thoppe , Vivek S. Borkar , D. Manjunath