[gmx-users] Retaining only .xtc files and deleting .trr files

[Anton Feenstra]

sunita at chem.iitb.ac.in wrote:

> Dear Kai,
> 
> Thank you for your response.
> 
> To restart the simulation I can use the last trr file as it contains
> velocity term in addition to coordinates. For this purpose I plan to keep
> the last trr file. Once I accumulate data for example 50 ns trajectory and
> make xtc file of whole 50 ns, can I delete the trr files?

I normaly store them on tape or dvd, then delete them. In addition, I 
only write a frame to the trr file every 20-50 ps or so (in stead of 1 
or 2 frames per ps for xtc).

> To be more specific, beside the usage you have specified which other
> programs uses only trr file but not xtc file.

None. As said, you loose the velocities and in addition you loose (some) 
precision on the coordinates. Coordinates in xtc are stored in 
nanometers with three decimal places. This is sufficient for all kinds 
analysis that I am aware of.


-- 
Groetjes,

Anton

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|  _   _  ___,| K. Anton Feenstra                                     |
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