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Related papers: Randomized LU-Householder CholeskyQR

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We analyze two algorithms for computing the symplectic $LL^T$ factorization $A=LL^T$ of a given symmetric positive definite symplectic matrix $A$. The first algorithm $W_1$ is an implementation of the $HH^T$ factorization from [Dopico et…

Numerical Analysis · Mathematics 2022-04-11 Maksymilian Bujok , Alicja Smoktunowicz , Grzegorz Borowik

The efficient and accurate QR decomposition for matrices with hierarchical low-rank structures, such as HODLR and hierarchical matrices, has been challenging. Existing structure-exploiting algorithms are prone to numerical instability as…

Numerical Analysis · Mathematics 2018-09-28 Daniel Kressner , Ana Susnjara

Efficient task scheduling is paramount in parallel programming on multi-core architectures, where tasks are fundamental computational units. QR factorization is a critical sub-routine in Sequential Least Squares Quadratic Programming…

Distributed, Parallel, and Cluster Computing · Computer Science 2025-06-12 Soumyajit Chatterjee , Rahul Utkoor , Uppu Eshwar , Sathya Peri , V. Krishna Nandivada

We present Flip-Flop Spectrum-Revealing QR (Flip-Flop SRQR) factorization, a significantly faster and more reliable variant of the QLP factorization of Stewart, for low-rank matrix approximations. Flip-Flop SRQR uses SRQR factorization to…

Numerical Analysis · Mathematics 2019-12-12 Yuehua Feng , Jianwei Xiao , Ming Gu

We present parallel and sequential dense QR factorization algorithms that are both optimal (up to polylogarithmic factors) in the amount of communication they perform, and just as stable as Householder QR. We prove optimality by extending…

Numerical Analysis · Mathematics 2008-08-21 James Demmel , Laura Grigori , Mark Hoemmen , Julien Langou

We introduce a Generalized LU-Factorization (\textbf{GLU}) for low-rank matrix approximation. We relate this to past approaches and extensively analyze its approximation properties. The established deterministic guarantees are combined with…

Numerical Analysis · Mathematics 2019-10-02 James Demmel , Laura Grigori , Alexander Rusciano

The selection of most informative and discriminative features from high-dimensional data has been noticed as an important topic in machine learning and data engineering. Using matrix factorization-based techniques such as nonnegative matrix…

Machine Learning · Computer Science 2022-10-04 Amir Moslemi , Arash Ahmadian

A fundamental problem when adding column pivoting to the Householder QR factorization is that only about half of the computation can be cast in terms of high performing matrix-matrix multiplications, which greatly limits the benefits that…

Numerical Analysis · Mathematics 2016-12-08 Per-Gunnar Martinsson , Gregorio Quintana-Orti , Nathan Heavner , Robert van de Geijn

The unpivoted and pivoted Householder QR factorizations are ubiquitous in numerical linear algebra. A difficulty with pivoted Householder QR is the communication bottleneck introduced by pivoting. In this paper we propose using random…

Numerical Analysis · Mathematics 2017-03-08 Stephen Becker , James Folberth , Laura Grigori

Many applications in scientific computing and data science require the computation of a rank-revealing factorization of a large matrix. In many of these instances the classical algorithms for computing the singular value decomposition are…

Numerical Analysis · Mathematics 2018-12-17 Abinand Gopal , Per-Gunnar Martinsson

We discuss a randomized strong rank-revealing QR factorization that effectively reveals the spectrum of a matrix $\textbf{M}$. This factorization can be used to address problems such as selecting a subset of the columns of $\textbf{M}$,…

Numerical Analysis · Mathematics 2025-03-25 Laura Grigori , Zhipeng Xue

LSQR and LSMR are iterative methods, based on the Golub-Kahan bidiagonalization algorithm, widely used for large-scale linear least squares problems. FLSQR and FLSMR are flexible variants of LSQR and LSMR, respectively, based on a flexible…

Numerical Analysis · Mathematics 2026-05-22 Alberto Bucci , Silvia Gazzola , Leonardo Robol

Previous studies have reported that common dense linear algebra operations do not achieve speed up by using multiple geographical sites of a computational grid. Because such operations are the building blocks of most scientific…

Distributed, Parallel, and Cluster Computing · Computer Science 2016-11-15 Emmanuel Agullo , Camille Coti , Jack Dongarra , Thomas Herault , Julien Langou

LU and Cholesky matrix factorization algorithms are core subroutines used to solve systems of linear equations (SLEs) encountered while solving an optimization problem. Standard factorization algorithms are highly efficient but remain…

Numerical Analysis · Mathematics 2022-07-25 Adolfo R. Escobedo

We present parallel and sequential dense QR factorization algorithms for tall and skinny matrices and general rectangular matrices that both minimize communication, and are as stable as Householder QR. The sequential and parallel algorithms…

Numerical Analysis · Mathematics 2008-09-16 James Demmel , Laura Grigori , Mark Hoemmen , Julien Langou

Kernel methods represent some of the most popular machine learning tools for data analysis. Since exact kernel methods can be prohibitively expensive for large problems, reliable low-rank matrix approximations and high-performance…

Numerical Analysis · Mathematics 2018-04-17 Jianwei Xiao , Ming Gu

Traditional post-training quantization (PTQ) is considered an effective approach to reduce model size and accelerate inference of large-scale language models (LLMs). However, existing low-rank PTQ methods require costly fine-tuning to…

Machine Learning · Computer Science 2026-01-12 Hongyaoxing Gul , Lijuan Hu , Shuzi Niu , Fangfang Liu

Tile low rank representations of dense matrices partition them into blocks of roughly uniform size, where each off-diagonal tile is compressed and stored as its own low rank factorization. They offer an attractive representation for many…

Distributed, Parallel, and Cluster Computing · Computer Science 2021-08-27 Wajih Boukaram , Stefano Zampini , George Turkiyyah , David Keyes

As multicore systems continue to gain ground in the High Performance Computing world, linear algebra algorithms have to be reformulated or new algorithms have to be developed in order to take advantage of the architectural features on these…

Mathematical Software · Computer Science 2008-06-12 Alfredo Buttari , Julien Langou , Jakub Kurzak , Jack Dongarra

The pivoted QLP decomposition is computed through two consecutive pivoted QR decompositions, and provides an approximation to the singular value decomposition. This work is concerned with a partial QLP decomposition of low-rank matrices…

Numerical Analysis · Mathematics 2023-07-06 Maboud F. Kaloorazi , Kai Liu , Jie Chen , Rodrigo C. de Lamare , Susanto Rahardja