GENERAL INFORMATION:

The FMM application implements a parallel adaptive Fast Multipole Method
to simulate the interaction of a system of bodies (N-body problem).  A
description of this implementation can be found in:

Singh, J. P., et. al.  A Parallel Adaptive Fast Multipole Method.
     Proceedings of Supercomputing 93, November 1993.

RUNNING THE PROGRAM:

To see how to run the program, please see the comment at the top of the
file fmm.C, or run the application with the "-h" command line option.
Optional command line parameters allow for individual processor timing 
statistics to be printed out, as well as the final particle positions.
Input parameters can be placed in an input file and redirected through 
standard input.  Of the nine input parameters, the ones which would 
normally be changed are the number of particles and the number of 
processors.  If other parameters are changed, these changes should be 
reported in any results that are presented.  Sample input files are 
included in the inputs subdirectory.  

Sample output for a 1 processor run with the input file inputs/input.256
and the timing and output flags specified is contained in the file 
correct.out.

BASE PROBLEM SIZE:

The base problem size for an upto-64 processor machine is 16,384 
particles.  For this many particles, you can use the input file provided 
(and change only the number of processors).

DATA DISTRIBUTION:

Our "POSSIBLE ENHANCEMENT" comments in the source code tell where one
might want to distribute data and how. Data distribution, however, does
not make much difference to performance on the Stanford DASH
multiprocessor.