Starlab version 4.4.1
    program created on Apr 29 2005 at 20:43:47
    source file     /home/steve/starlab/src/node/dyn/hdyn/evolve/kira.C

Hermite N-body integrator with evolving hierarchical tree structure,
stellar and binary evolution, and an arbitrary external field.  The
program reads a snapshot from standard input and writes snapshot(s)
to standard output.  Periodic log output is sent to standard error.

Basic options are listed below.  Default values for a new simulation
are indicated in square brackets.  For restart (continuation of a
previous kira calculation), the defaults for many options [*] are
determined from the input snapshot, making it possible to continue
a run without having to re-specify all the command-line parameters
previously used.  (These new defaults may still be overridden on
the command line, of course.)  Some options typically having to do
with initial setup may be overridden by data from the input
snapshot (if present), as noted below.  Kira may also turn *on*
some options (the B, G, S, and u settings) if they were turned
on in the previous run, but are not specified on the current
command line.  To prevent this, use the "-o" switch.

The first page of log output gives detailed information on all
parameter settings adopted and any modifications made during
initialization.  In case of doubt, read the log file!

Usage: kira [OPTIONS] < infile > output

Options:
             -0    force non-GRAPE operation, if relevant
             -1    suppress density calculation [compute with GRAPE]
             -2    enable DMA GRAPE access (experimental) [no DMA]
             -3    enable special treatment of isolated multiples [no]
             -a    specify accuracy parameter [0.1][*]
             -A    enable "alternate" output [off]
             -b    specify frequency of full binary output, in (integer)
                   units of the log output interval
                   [10; no argument or 0 ==> no output]
             -B    turn on binary evolution [off][*]
             -c    include comment [none]
             -C    specify GRAPE release interval, in seconds [15]
             -d    specify log output interval [1][*]
             -D    specify snapshot interval [end of run]. 
                   Special values:
                               xN: formatted full dump, frequency N;
                               XN: unformatted full dump, frequency N;
                               full/all: same as x1;
                               b: track binary changes only (formatted);
                               B: track binary changes (unformatted);
             -e    specify softening length [0][*]
             -E    use exact calculation [false]
             -f    turn on/off internal dynamical friction on stars [0][*]
             -F    turn on external dynamical friction on the cluster,
                   and optionally specify a scaling coefficient [none]
             -g    specify hysteresis factor [2.5][*]
             -G    specify initial stripping radius [none][*]
             -h    specify stellar-evolution time step [0.015625 = 1/64][*]
             -i    ignore all internal forces (i.e. external only) [false]
             -I    specify (re)initialization timescale [1][*]
             -k    specify perturbation factor [1.e-7][*]
             -K    specify log2(maximum slowdown factor) (integer): [0][*]
             -l    specify close-encounter distance [0.25 --> 0.25/N][*]
                   [option renamed from -f, 7/04]
             -L    specify CPU time limit, in seconds [none]
             -n    stop at specified number of particles [5]
             -N    specify frequency of CPU check output [50000]
             -o    prevent kira from overriding some settings (BGSu)
                   based on input snapshot data [allow]
             -O    save (and overwrite) extra snapshot at each output [no]
             -q    specify initial virial ratio [0.5]
             -r    specify initial virial radius (may not be
                   specified in the input snap) [no]
             -R    specify snapshot file for (re)start [none: use stdin]
             -s    specify random seed [take from system clock]
             -S    turn on stellar evolution [off][*]
             -t    specify time span of calculation [10]
             -T    enable experimental threading and specify n_threads [0]
             -u    toggle unperturbed multiple motion [disabled][*]
             -U    toggle all unperturbed motion [enabled][*]
             -v    toggle "verbose" mode [on]
             -W    specify full-dump (worldline) timescale [1]
             -x    toggle output of extended-precision time [on]
             -X    specify escaper removal timescale [reinit][*]
             -y    specify stellar encounter criterion
                   [0 N-body units or solar radii][*]
             -z    specify stellar merger criterion [0 stellar radii][*]
             -Z    specify stellar tidal dissipation criterion
                   [0 stellar radii][*]

As a convenient shorthand, any "dt" interval specified less than zero
is interpreted as a power of 2, i.e. "-d -3" sets dt_log = 0.125.  In
the case of dt_snap, this will also cause snapshot data to be written
immediately on restart (usually we wait until time dt_snap).

Written by J. Makino, S. McMillan, S. Portegies Zwart, and P. Hut, .

Report bugs to starlab (at) sns.ias.edu.