[gmx-users] Writing initial coordinates to trajectory files

[Brian Helfrich]

Berk Hess wrote:
> The initial coordinates are written immediately to the trr file,
> although the file system might buffer data, you so could have to wait
> until some more frames have been written.

Thanks, I see that now. It seems that somewhere between grompp and 
mdrun's initial trajectory output, my initial coordinates did change 
ever so slightly:

after_em.gro:
    1LYSH     N    1   2.105   0.744   2.070
    1LYSH    H1    2   2.056   0.668   2.027
    1LYSH    H2    3   2.190   0.761   2.021

full.trr:
   natoms=      9035  step=         0  time=0.0000000e+00  lambda=         0
   ...
      x[    0]={ 2.10518e+00,  7.43687e-01,  2.07004e+00}
      x[    1]={ 2.05600e+00,  6.68002e-01,  2.02700e+00}
      x[    2]={ 2.19043e+00,  7.61087e-01,  2.02075e+00}

But step 0 coordinates are output as you said, thanks.
--Brian.

-- 
Brian Helfrich
www.nanorex.com