activity
20152025
most citedSMASH: Structured matrix approximation by separation and hierarchy

2 citations · 4 across the 10 of their papers we have counts for

collaborators
Showing math.NAShow all

8 papers · 1 filter

math.NA2025

Preconditioned Truncated Single-Sample Estimators for Scalable Stochastic Optimization

Tianshi Xu, Difeng Cai, Hua Huang +2

Many large-scale stochastic optimization algorithms involve repeated solutions of linear systems or evaluations of log-determinants. In these regimes, computing exact solutions is…

math.NA2025

Data-Driven Self-Supervised Learning for the Discovery of Solution Singularity for Partial Differential Equations

Difeng Cai, Paulina Sepúlveda

The appearance of singularities in the function of interest constitutes a fundamental challenge in scientific computing. It can significantly undermine the effectiveness of numeric…

math.NA2022

Data-Driven Linear Complexity Low-Rank Approximation of General Kernel Matrices: A Geometric Approach

Difeng Cai, Edmond Chow, Yuanzhe Xi

A general, {\em rectangular} kernel matrix may be defined as where is a kernel function and where and are two…

math.NA2022★ 2 cited

Data-driven Construction of Hierarchical Matrices with Nested Bases

Difeng Cai, Hua Huang, Edmond Chow +1

Hierarchical matrices provide a powerful representation for significantly reducing the computational complexity associated with dense kernel matrices. For general kernel functions,…

math.NA2021

Hybrid A Posteriori Error Estimators for Conforming Finite Element Approximations to Stationary Convection-Diffusion-Reaction equations

Difeng Cai, Zhiqiang Cai

We consider the a posteriori error estimation for convection-diffusion-reaction equations in both diffusion-dominated and convection/reaction-dominated regimes. We present an expli…

math.NA2021

Fast deterministic approximation of symmetric indefinite kernel matrices with high dimensional datasets

Difeng Cai, James Nagy, Yuanzhe Xi

Kernel methods are used frequently in various applications of machine learning. For large-scale high dimensional applications, the success of kernel methods hinges on the ability t…

math.NA2017★ 2 cited

SMASH: Structured matrix approximation by separation and hierarchy

Difeng Cai, Edmond Chow, Yousef Saad +1

This paper presents an efficient method to perform Structured Matrix Approximation by Separation and Hierarchy (SMASH), when the original dense matrix is associated with a kernel f…

math.NA2015

An Explicit Upper Bound for Modulus of Divided Difference on a Jordan Arc in the Complex Plane

Difeng Cai

An explicit upper bound is derived for the modulus of divided difference for a smooth(not necessarily analytic) function defined on a smooth Jordan arc (or a smooth Jordan curve) i…