English
Related papers

Related papers: Iterative Refinement of Schur decompositions

200 papers

We present and analyze an efficient implementation of an iteratively reweighted least squares algorithm for recovering a matrix from a small number of linear measurements. The algorithm is designed for the simultaneous promotion of both a…

Numerical Analysis · Mathematics 2011-07-19 Massimo Fornasier , Holger Rauhut , Rachel Ward

We consider solvable matrix models. We generalize Harish-Chandra-Itzykson-Zuber and certain other integrals (Gross-Witten integral and integrals over complex matrices) using the notion of tau function of matrix argument. In this case one…

Mathematical Physics · Physics 2007-05-23 A. Yu. Orlov

A matrix algorithm runs superfast (aka at sublinear cost) if it involves much fewer flops and memory cells than an input matrix has entries. Big Data are frequently represented by matrices of immense sizes that cannot be handled directly…

Numerical Analysis · Mathematics 2025-11-11 Qi Luan , Victor Y. Pan

Most existing work uses dual decomposition and subgradient methods to solve Network Utility Maximization (NUM) problems in a distributed manner, which suffer from slow rate of convergence properties. This work develops an alternative…

Optimization and Control · Mathematics 2015-03-17 Ermin Wei , Asuman Ozdaglar , Ali Jadbabaie

Often, polynomials or rational functions, orthogonal for a particular inner product are desired. In practical numerical algorithms these polynomials are not constructed, but instead the associated recurrence relations are computed.…

Numerical Analysis · Mathematics 2023-11-28 Marc Van Barel , Niel Van Buggenhout , Raf Vandebril

We describe a three precision variant of Newton's method for nonlinear equations. We evaluate the nonlinear residual in double precision, store the Jacobian matrix in single precision, and solve the equation for the Newton step with…

Numerical Analysis · Mathematics 2023-10-11 C. T. Kelley

The textbook Newton's iteration is practically inapplicable on solutions of nonlinear systems with singular Jacobians. By a simple modification, a novel extension of Newton's iteration regains its local quadratic convergence toward…

Numerical Analysis · Mathematics 2024-04-22 Zhonggang Zeng

We introduce a novel eigenvalue algorithm for near-diagonal matrices inspired by Rayleigh-Schr\"odinger perturbation theory and termed Iterative Perturbative Theory (IPT). Contrary to standard eigenvalue algorithms, which are either…

Numerical Analysis · Mathematics 2022-11-18 Maseim Kenmoe , Ronald Kriemann , Matteo Smerlak , Anton S. Zadorin

This paper introduces a notion of decomposition and completion of sum-of-squares (SOS) matrices. We show that a subset of sparse SOS matrices with chordal sparsity patterns can be equivalently decomposed into a sum of multiple SOS matrices…

Optimization and Control · Mathematics 2020-01-13 Yang Zheng , Giovanni Fantuzzi , Antonis Papachristodoulou

We give a self-contained randomized algorithm based on shifted inverse iteration which provably computes the eigenvalues of an arbitrary matrix $M\in\mathbb{C}^{n\times n}$ up to backward error $\delta\|M\|$ in…

Numerical Analysis · Mathematics 2022-05-16 Jess Banks , Jorge Garza-Vargas , Nikhil Srivastava

We explore and analyze the use of multiprecision arithmetic for several classes of Schwarz methods and preconditioners, where the approximate solution of the local problems is performed at a lower precision, i.e., with fewer digits of…

Numerical Analysis · Mathematics 2025-09-30 Michal Outrata , Daniel B. Szyld

Iterative refinement is particularly popular for numerical solution of linear systems of equations. We extend it to Low Rank Approximation of a matrix (LRA) and observe close link of the resulting algorithm to oversampling techniques,…

Numerical Analysis · Mathematics 2024-11-28 Victor Y. Pan , Qi Luan , Soo Go

Estimation of actual errors from the residue in iterative solutions is necessary for efficient solution of large problems when their condition number is much larger than one. Such estimators for conjugate gradient algorithms used to solve…

Numerical Analysis · Mathematics 2014-06-27 Aashish Vishwakarma , Murugesan Venkatapathi

The Schur index in four-dimensional $\mathcal{N}=4$ super Yang-Mills theory with $U(N)$ gauge group has a natural two-parameter deformation. We find that a matrix integral in such a deformed Schur index can be exactly evaluated by using…

High Energy Physics - Theory · Physics 2025-03-07 Yasuyuki Hatsuda

In this paper we focus on the solution of shifted quasiseparable systems and of more general parameter dependent matrix equations with quasiseparable representations. We propose an efficient algorithm exploiting the invariance of the…

Numerical Analysis · Mathematics 2017-08-07 Paola Boito , Yuli Eidelman , Luca Gemignani

Clinically useful proton Computed Tomography images will rely on algorithms to find the three-dimensional proton stopping power distribution that optimally fits the measured proton data. We present a least squares iterative method with many…

Medical Physics · Physics 2021-05-12 Don F. DeJongh , Ethan A. DeJongh

We introduce a new iterative rounding technique to round a point in a matroid polytope subject to further matroid constraints. This technique returns an independent set in one matroid with limited violations of the other ones. On top of the…

Data Structures and Algorithms · Computer Science 2018-11-26 André Linhares , Neil Olver , Chaitanya Swamy , Rico Zenklusen

In this paper, we consider the Newton-Schur method in Hilbert space and obtain quadratic convergence. For the symmetric elliptic eigenvalue problem discretized by the standard finite element method and non-overlapping domain decomposition…

Numerical Analysis · Mathematics 2022-05-05 Nian Shao , Wenbin Chen

We present a general approach to rounding semidefinite programming relaxations obtained by the Sum-of-Squares method (Lasserre hierarchy). Our approach is based on using the connection between these relaxations and the Sum-of-Squares proof…

Data Structures and Algorithms · Computer Science 2013-12-24 Boaz Barak , Jonathan Kelner , David Steurer

In this paper, we describe a new algorithm that approximates the extreme eigenvalue/eigenvector pairs of a symmetric matrix. The proposed algorithm can be viewed as an extension of the Jacobi eigenvalue method for symmetric matrices…

Numerical Analysis · Mathematics 2025-09-16 Cristian Rusu