[gmx-users] file too big?

[Anton Feenstra]

David van der Spoel wrote:
> On Wed, 2003-04-30 at 10:16, Francesco Tordini wrote:
> 
.>>It works well with file .trr, but in my case i need to split the .xtc
>>file (the .trr file was too big for my disk and i save it only every
>>5000fs for restarting dynamics), and it don't seems to work.

Writing xtc in the first place is a smart move!

>> Do you know if this method applies also to .xtc files?
> 
> No it doesn't, xtc files do not have the same size per frame.

Which reminds me, there used to be a quick & dirty tool in Groningen
to search a file for the magic number that each frame starts with.
Using split, and then that tool, you should be able to get going.
You will loose one frame, though, unless you split again taking the
'half frame' size into account. It's probably not worth trying to
get hold of the source, it's too easy to implement yourself; you
simply scan the file byte by byte and compare with the magic number
(IIRC it's 1997 for .xtc, but probably different for .trr, so you
should check the relevant source in gmxlib.)


-- 
Groetjes,

Anton
  _____________ _______________________________________________________
|             |                                                       |
|  _   _  ___,| K. Anton Feenstra                                     |
| / \ / \'| | | Dept. of Pharmacochem. - Vrije Universiteit Amsterdam |
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