University of Washington N-Body Shop

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Contained are the software tools developed by the NASA HPCC ESS group at the University of Washington. These tools may be freely obtained (see each tool for details) and used. We encourage you to send your name and e-mail address to,

This will put you onto our mailing list so that you can be notified of new releases of any of the tools. You may also send questions and comments to the same e-mail address.

  • TIPSY: Theoretical Image Processing System

  • SMOOTH: Code for calculating mean-field quantities in N-body simulations, for example the density at every particle position.

  • SKID: Code to find gravitationally bound groups in N-body simulations.

  • FOF: A friends-of-friends group finder for N-body simulations.

  • AFOF: A fast approximate friends-of-friends group finder.

  • DIRECT: An O(N^2) direct sum gravity tool, useful for testing other codes and for calculating small N systems. Now supports periodic boundary conditions!

  • NCHILADA: (under development) A framework for the parallel analysis and visualization of N-body simulations.

The software shown above is written and maintained by the HPCC Group in the UW Department of Astronomy.

We offer the following pointers to software NOT supported by this group, but written by other participants in this project: Snyder and Lin's ZPL Programming Language Project and Hugh Couchman's Hydra: a parallel adaptive grid code with SPH.

Anonymous ftp-site at the Department of Astronomy of the University of Washington.

N-Body Shop
University of Washington
Box 351580
Seattle, WA  98195-1580
(206) 543-2888 voice, (206) 685-0403 FAX
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