[gmx-users] Converting a new-version .tpr file to an old-version .tpr file

[Justin A. Lemkul]

Andrew DeYoung wrote:
> Hi,
> 
> I ran a simulation using Gromacs 4.5.5.  However, I would like to use g_sdf
> to compute a spatial distribution function.  As mentioned in a post (
> http://lists.gromacs.org/pipermail/gmx-users/2012-March/069073.html ), this
> old no longer available g_sdf might be more flexible than g_spatial in some
> cases.  So, I fed my .tpr file which was created using Gromacs 4.5.5 into
> g_sdf using Gromacs 4.0.5 (I have both versions on my computer).  When I
> tried this, I got the following error message:
> 
> -------------------------------------------------------
> Program g_sdf, VERSION 4.0.5
> Source code file: tpxio.c, line: 1683
> 
> Fatal error:
> reading tpx file (nvt2dy.tpr) version 73 with version 58 program
> -------------------------------------------------------
> 
> This is a strange question, but is it possible to convert a .tpr file from
> version 73 back to version 58?
> 

Not directly.  You need to make a new .tpr file using grompp from the version 
you want (4.0.5 in this case).  That may require you to make some small 
modifications to your 4.5.5 topology (since the force field structure is 
different, but #include statements should still work) and .mdp file (depending 
on the keywords used).

-Justin

-- 
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Justin A. Lemkul
Ph.D. Candidate
ICTAS Doctoral Scholar
MILES-IGERT Trainee
Department of Biochemistry
Virginia Tech
Blacksburg, VA
jalemkul[at]vt.edu | (540) 231-9080
http://www.bevanlab.biochem.vt.edu/Pages/Personal/justin

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