Accession Number:

ADA129676

Title:

An Efficient Program for Many-Body Simulations (or, Cray Performance from a VAX).

Descriptive Note:

Interim rept.,

Corporate Author:

CARNEGIE-MELLON UNIV PITTSBURGH PA DEPT OF COMPUTER SCIENCE

Personal Author(s):

Report Date:

1983-03-01

Pagination or Media Count:

26.0

Abstract:

The simulation of N particles interacting in a gravitational force field is useful in astrophysics, but such simulations become costly for large N. Representing the universe as a tree structure with the particles at the leaves and internal nodes labelled with the centers of mass of their descendants allows several simultaneous attacks on the computation time required by the problem. These approaches range from algorithmic changes replacing an ON2 algorithm with an ON log N algorithm to data structure modifications, code-tuning, and hardware modifications. The changes reduced the running time of a large problem N 10,000 by a factor of four hundred. This paper describes both the particular program and the methodology underlying such speedups.

Subject Categories:

  • Astrophysics
  • Theoretical Mathematics
  • Computer Programming and Software

Distribution Statement:

APPROVED FOR PUBLIC RELEASE