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 function. Given the points in a domain, a tree structure is first constructed based on an adaptive partition of the computational domain to facilitate subsequent approximation procedures. In contrast to existing schemes based on either analytic or purely algebraic approximations, SMASH takes advantage of both approaches and greatly improves efficiency. The algorithm follows a bottom‐up traversal of the tree and is able to perform the operations associated with each node on the same level in parallel. A strong rank‐revealing factorization is applied to the initial analytic approximation in the
 NSFPAR ID:
 10064820
 Publisher / Repository:
 Wiley Blackwell (John Wiley & Sons)
 Date Published:
 Journal Name:
 Numerical Linear Algebra with Applications
 Volume:
 25
 Issue:
 6
 ISSN:
 10705325
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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