Assuming NEMO is part of your UNIX environment, let us setup an encounter between two equal mass Plummer spheres:
% mkplummer out=p1 nbody=1024
% mkplummer out=p2 nbody=1024
% snapstack in1=p1 in2=p2 out=p3 deltar=-10,0, deltav="-sqrt(2),0,0"
nbody1 = 1024 nbody2 = 1024
The file p3 now contains a snapshot ready for integration. This file is a binary file, and it's contents can be viewed with the tsf program:
% tsf p3
char Headline[33] "set_xrandom: seed used 781656448"
char History[70] "snapstack in1=p1 in2=p2 out=p3 deltar=-10,0, deltav=-
sqrt(2),0,0 1.1b"
char History[41] "mkplummer out=p1 nbody=1024 VERSION=2.5a"
char History[41] "mkplummer out=p2 nbody=1024 VERSION=2.5a"
set SnapShot
set Parameters
int Nobj 04000
tes
set Particles
int CoordSystem 0201402
double Mass[2048] 0.000976562 0.000976562 0.000976562 0.000976562
0.000976562 0.000976562 0.000976562 0.000976562 0.000976562
0.000976562 0.000976562 0.000976562 0.000976562 0.000976562
0.000976562 0.000976562 0.000976562 0.000976562 0.000976562
. . .
double PhaseSpace[2048][2][3] -5.31134 -0.312107 0.374856 0.649829
-0.494992 -0.354558 -5.32339 -0.224862 -0.673369 -0.425955
-0.211239 -0.0150187 -5.36356 -0.149557 0.390671 -0.0420343
0.752242 -0.305977 -5.39578 -0.635058 -0.0153547 0.956519
. . .
tes
tes