[gmx-users] Box vector question

[Marc Charendoff]

Hey all.

I'm trying to visualize a *.gro file w/VMD and am
having no luck. VMD developer says:

Hi,
  Here's the only .gro file format spec I can find
presently:
http://www.gromacs.org/documentation/reference/online/gro.html

My understanding of that specification is that while
the last 6
of the 9 box vectors may be omitted, the first three
may not.
If I understand correclty, this means that files that
are
completely missing the box vectors are illegally
formatted.
Perhaps a Gromacs developer or expert could comment on
this?

  John Stone
  vmd at ks.uiuc.edu

. . . I cut and paste three floating box vectors into
*,gro file and get nothing. What am I missing?? Is
there a specific method to generating box vectos?

e.g. file:

PRODRG COORDS
   22
    1AHL  CAS      1  -0.052  -0.933  -0.149
    1AHL  CAR      2  -0.108  -0.803  -0.090
 
.........................................................................

    1AHL  C       21   0.131   0.790   0.181
    1AHL  O       22   0.218   0.798   0.272
     5.90620   6.84510   3.05170