[gmx-users] Simulation Box

[Hadas Lapid]

I wanted to know weather on the output .gro (/ .pdb) trajectory file 
the boundary corner of the simulation box is located conventionally at 
(0,0,0) coordinates.
and if not, how can I find the coordinates of the box (its boundaries) 
without having to sort the molecular coordinates of all atoms in search 
for extremal values of x,y and z in each frame?
Sincerely,
Hadas