[gmx-developers] trjcat -nokeeplast with append

[Anton Feenstra]

Roland Schulz wrote:
> Hi,
> 
> when using trjcat in append mode without -keeplast it does not really do 
> what the documentation says.
> 
> While the documentation says "Obviously the file to
> append to has to be the one with lowest starting time since one can only
> append at the end of a file." It does not say that it implies keeplast 
> for the first appended trajectory.
> 
> But I think this is not only not documented correctly but the behavior 
> itself is misleading. Because usually one wants to have -nokeeplast 
> (good default).

The last frame of the first traj should (normally) match the first of 
the second. Isn't it therefore the simplest option to start appending 
the first 'non overlapping' frame of the second traj to the first? 
(Although I don't remember now if the code actually checks whether the 
frames actually match.)

Since trjcat is aimed at producing 'continuous' trajectories, IMHO it is 
obvious that you 'keep last' when appending.


-- 
Groetjes,

Anton
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|  _   _  ___,| K. Anton Feenstra                                     |
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