The computational system of units is determined by the input data. No explicit assumtions about the value of the gravitational constant have been made; it is read in as a parameter. Particles are not required to have identical masses.
The first one is the input parameter file with the name SCFPAR. 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:
Comment Private comment. (cannot be a null string) headline Identification string for the run (max 50 char) [test] nsteps Number of timesteps  noutbod Output system state (file SNAPxxx) once every noutbod steps  noutlog Output logfile data (file SCFMLOG) once every noutlog steps  dtime Integration timestep [0.01] gravconst Gravitional Constant  selfgrav [.TRUE.] inptcoef [.FALSE.] outpcoef [.FALSE.] zeroodd [.FALSE.] zeroeven [.FALSE.] fixacc [.FALSE.]Note that the first line is a redundant comment not used by the program, but needs to be present.
The second file has to be named SCFBI, and contains the input bodies. The first line must contain the number of bodies, and the time of this snapshot, followed by
Output files created are SNAPxxx, which contains all the requested (see noutbod) output snapshots, one for each requested output time in ascii ntmpv(5NEMO) format.
which contains a log (see noutlog) of the run and SCFBO, which contains a binary (machine dependable) dump of the last snapshot. Note that these 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.
runscfm 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.
snapprint in=i.snap options=m,x,y,z,vx,vy,vz header=t > i.tab
Converting output tables made by scfm into snapshot(5NEMO)
can be done
tabtos in=p.tab out=o.snap header=nbody,time block1=mass,pos,vel
machine cpu N-body US-140 143" 1000 US-140 269" 2000 US-140 611" 4000 US-140 1072" 8000 US-140 .... 16000 US-2 380 8000
SCFPAR input parameters (ascii) SCFBI input bodies (ascii) SCFLOG output logfile SCFOUT output something (’termfile’) SCFELxxx output something (1/body) SNAPxxx output bodies SCFICOEF input coefficients file SCFOCOEF output coefficients file ~/usr/lars/scfm/ original LARS version ~/src/nbody/evolve/scfm/ original LARS version
Pentium-333 6.93s Pentium-500 4.58 Pentium-933 2.76 Ultra-10/300 9.64 (g77 -O) 7.20 (f77 -O) 7.33 (f77 -fast)
Hernquist, L. & Ostriker, J. (1992) A Self-Constistent Field Method for Galactic Dynamics, ApJ. 386, 375.
hernquist, sigurdsson, bryan - 1995 - a parallel scf code - apj 446, 717
1-jan-91 V1 Public release created Lars Hernquist (@UCB) 7-jul-97 integrated in NEMO/usr tree PJT 20-jan-98 integrated in NEMO/src tree PJT 18-dec-99 fixed some Makefile bugs, added bench timings PJT
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