Computational units can be anything, but the gravitational constant G=1.
The first one is the input parameter file with the name TREEPAR. It contains, line by line, the input parameters for this run. In the table below the values for the benchmark input parameter file are given in square brackets:
headline Identification string for the run (max 50 char) [standard NEMO bench] nsteps Number of timesteps  noutbod Output system state (file TREEBOA) once every nsteps/noutbod steps  noutlog Output logfile data (file TREELOG) once every nsteps/noutlog steps  dtime Integration timestep [0.03125] tol Error tolerance; 0.0=exact [1.0] eps Potential softening parameter [0.05] usequad Option to include quadrupole terms (.TRUE./.FALSE.) [.FALSE.]
The second file has to be named TREEBI, and contains the input bodies in a format described in stoa(1NEMO) .
Output files created are TREEBOA, which contains all the requested (see noutbod) output snapshots in ascii atos(1NEMO) format, TREELOG, which contains a log (see noutlog) of the run and TREEBO, which contains a binary (machine dependable) dump of the last snapshot. Note that these three output files must not be present when the program is to be run. (ANSI FORTRAN)
To avoid excessive overhead, noutlog should be larger than 1, typically ~ 10, depending on total number of steps though.
runtreecode2 input_snapshot output_snapshot pars_file
The input_snapshot and output_snapshot are now in snapshot(5NEMO) format, whereas the pars_file is in the format described in the previous PARAMETERS section.
A regular NEMO program treecode0 can also be used. Although very similar in operation to the abovementioned script, it makes running multiple versions of the programs a bit more transparant, and equal to running other programs in the NEMO environment.
machine cpu compiler OS Cray YMP 1.625 cf77 -dp Unicos ... SGI 8.5 f77 -O3 IRIX Release 4.0.5F System V SGI 11.9 f77 -O IRIX Release 4.0.5F System V Sparc 10/30 9.3 f77 -cg89 -dalign -fast -O SUN OS 4.1.3 - SC1.0 Sparc 10/30 8.6 f77 -cg92 -dalign -fast -O SUN OS 4.1.3 - SC2.0.1 Sparc 10/30 8.0 f77 -cg92 -dalign -fast -O4 -libmil SUN OS 4.1.3 - SC2.0.1 Sparc 10/51 6.6 f77 -cg92 -dalign -fast -O4 -libmil SUN OS 5.3 - SC2.0.1 Sparc 1 (4/60) 68.5 f77 -O SUN OS 4.1.3 - SC1.0 Sparc 1 (4/60) 56.2 f77 -cg89 -dalign -fast -O SUN OS 4.1.3 - SC1.0 Sun 3/60 1784.0 f77 -O SUN OS 4.1.1 - SC1.0
~/usr/lars/treecode2/ original LARS version ~/src/nbody/evolve/treecode2/ official NEMO version (ASCII atos/stoa I/O)
xx-xxx-xx V2 allows quadrupole terms Lars Hernquist (@UCB) xx-xxx-xx V2.1 optimized 2D and 3D versions of the code LH 1-sep-86 V2.2 allow arbitrary large values of tol= LH 18-nov-88 ’V2’ non-recursive vectorized version LH (@IAS) xx-apr-90 Directory made for NEMO’s export PJT 5-jun-90 Document created PJT 23-oct-91 Cray tests - disabled SECOND in treeutil.f PJT 15-apr-94 added benchmark docs PJT
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