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Traditional numerical methods, such as the finite element method and finite volume method, adress partial differential equations (PDEs) by discretizing them into algebraic equations and solving these iteratively. However, this process is…

Computational Physics · Physics 2025-07-22 Jianghang Gu , Ling Wen , Yuntian Chen , Shiyi Chen

Unsupervised homogeneous network embedding (NE) represents every vertex of networks into a low-dimensional vector and meanwhile preserves the network information. Adjacency matrices retain most of the network information, and directly…

Social and Information Networks · Computer Science 2020-03-06 Luoyi Zhang , Ming Xu

An efficient low-order scaling method is presented for large-scale electronic structure calculations based on the density functional theory using localized basis functions, which directly computes selected elements of the density matrix by…

Strongly Correlated Electrons · Physics 2010-05-04 Taisuke Ozaki

In this paper we present the theoretical framework needed to justify the use of a kernel-based collocation method (meshfree approximation method) to estimate the solution of high-dimensional stochastic partial differential equations…

Numerical Analysis · Mathematics 2012-09-11 Igor Cialenco , Gregory E. Fasshauer , Qi Ye

In this work, we develop a new fast algorithm, spaQR -- sparsified QR, for solving large, sparse linear systems. The key to our approach is using low-rank approximations to sparsify the separators in a Nested Dissection based Householder QR…

Numerical Analysis · Mathematics 2020-10-15 Abeynaya Gnanasekaran , Eric Darve

In an iterative approach for solving linear systems with ill-conditioned, symmetric positive definite (SPD) kernel matrices, both fast matrix-vector products and fast preconditioning operations are required. Fast (linear-scaling)…

Numerical Analysis · Mathematics 2021-01-13 Xin Xing , Hua Huang , Edmond Chow

The integral equation method is widely used in numerical simulations of 2D/3D acoustic and electromagnetic scattering problems, which needs a large number of values of the Green's functions. A significant topic is the scattering problems in…

Numerical Analysis · Mathematics 2018-07-26 Bo Zhang , Ruming Zhang

A blurring algorithm with linear time complexity can reduce the small-scale content of data observed at scattered locations in a spatially extended domain of arbitrary dimension. The method works by forming a Gaussian interpolant of the…

Computation · Statistics 2020-09-22 Gregor Robinson , Ian Grooms

Computation of the trace of a matrix function plays an important role in many scientific computing applications, including applications in machine learning, computational physics (e.g., lattice quantum chromodynamics), network analysis and…

Data Structures and Algorithms · Computer Science 2017-03-10 Insu Han , Dmitry Malioutov , Haim Avron , Jinwoo Shin

A new fast multipole formulation for solving elliptic difference equations on unbounded domains and its parallel implementation are presented. These difference equations can arise directly in the description of physical systems, e.g.…

Computational Physics · Physics 2016-04-08 Sebastian Liska , Tim Colonius

We consider the approximate computation of spectral projectors for symmetric banded matrices. While this problem has received considerable attention, especially in the context of linear scaling electronic structure methods, the presence of…

Numerical Analysis · Mathematics 2016-08-04 Daniel Kressner , Ana Susnjara

During the past three decades, the advantageous concept of the Green's function has been extended from linear systems to nonlinear ones. At that, there exist a rigorous and an approximate extensions. The rigorous extension introduces the…

Mathematical Physics · Physics 2018-03-28 Asatur Khurshudyan

We show that the expected solution operator of prototypical linear elliptic partial differential operators with random coefficients is well approximated by a computable sparse matrix. This result is based on a random localized orthogonal…

Numerical Analysis · Mathematics 2020-03-17 Michael Feischl , Daniel Peterseim

Some important applicative problems require the evaluation of functions $\Psi$ of large and sparse and/or \emph{localized} matrices $A$. Popular and interesting techniques for computing $\Psi(A)$ and $\Psi(A)\mathbf{v}$, where $\mathbf{v}$…

Numerical Analysis · Mathematics 2022-04-25 Daniele Bertaccini , Marina Popolizio , Fabio Durastante

We present an interface between PineAPPL and Matrix, which allows fully differential cross sections to be calculated in the form of interpolation grids, accurate at next-to-next-to-leading order (NNLO) in QCD and next-to-leading order in…

High Energy Physics - Phenomenology · Physics 2026-05-29 S. Devoto , T. Jezo , S. Kallweit , C. Schwan

Much recent work has addressed the solution of a family of partial differential equations by computing the inverse operator map between the input and solution space. Toward this end, we incorporate function-valued reproducing kernel Hilbert…

Numerical Analysis · Mathematics 2022-04-05 Kaijun Bao , Xu Qian , Ziyuan Liu , Songhe Song

Many matrices appearing in numerical methods for partial differential equations and integral equations are rank-structured, i.e., they contain submatrices that can be approximated by matrices of low rank. A relatively general class of…

Numerical Analysis · Mathematics 2015-03-10 Steffen Börm , Knut Reimer

We consider the quantum complexity of estimating matrix elements of unitary irreducible representations of groups. For several finite groups including the symmetric group, quantum Fourier transforms yield efficient solutions to this…

Quantum Physics · Physics 2009-04-21 Stephen P. Jordan

A linear algebraic method named the shifted conjugate-orthogonal-conjugate-gradient method is introduced for large-scale electronic structure calculation. The method gives an iterative solver algorithm of the Green's function and the…

Materials Science · Physics 2007-05-23 R. Takayama , T. Hoshi , T. Sogabe , S. -L. Zhang , T. Fujiwara

We study the problem of approximating orthogonal matrices so that their application is numerically fast and yet accurate. We find an approximation by solving an optimization problem over a set of structured matrices, that we call extended…

Numerical Analysis · Mathematics 2021-03-24 Cristian Rusu , Lorenzo Rosasco