Xref: utzoo ont.events:1465 uw.talks:148 uw.cs.grad:128 Path: utzoo!utgpu!watserv1!watmath!maytag!water!wlrush From: wlrush@water.waterloo.edu (Wenchantress Wench Wendall) Newsgroups: ont.events,uw.talks,uw.cs.grad Subject: SCIENTIFIC COMPUTATION SEMINAR Keywords: Professor Rob H. Bisseling, Koninklijke/Sheel-Laboratorium, Message-ID: <2967@water.waterloo.edu> Date: 7 Feb 90 13:59:08 GMT Distribution: ont Organization: U of Waterloo, Ontario Lines: 47 Amsterdam. DEPARTMENT OF COMPUTER SCIENCE UNIVERSITY OF WATERLOO SEMINAR ACTIVITIES SCIENTIFIC COMPUTATION SEMINAR Professor Rob H. Bisseling, Koninklijke/Shell- Laboratorium, Amsterdam will speak on ``Parallel Sparse Linear System Solving on a Transputer Network. TIME: 3:30 p.m. ROOM: DC 1304 DATE: Monday, February 12, 1990 *NOTE DATE!* ABSTRACT Large sparse systems of linear equations are important in many areas, such as e.g. PDE-solving and Linear Programming. This talk presents a parallel algorithm for the direct solution of a sparse linear system Ax = b on a local memory MIMD computer. The algorithm -- - - consists of the LU decomposition of A, followed by the - solution of two triangular systems. The matrix A is distributed across the processors - according to the grid (i.e., scattered) distribution. Each processor represents the nonzeroes of its part of the sparse matrix by a two-dimensional linked list. The pivot elements of the LU decomposition are determined by a Markowitz criterion to preserve sparsity, with threshold pivoting to maintain numerical stability. The algorithm has been implemented in Occam 2, and experimental results have been obtained on a mesh of 36 transputers. This algorithm is part of the PARPACK library of parallel programs for dense and sparse matrix computations which is currently under development at KSLA.