From: John Stone (
Date: Fri Jun 26 2009 - 14:26:51 CDT

  You need to call "$sel frame" and "$sel update" yourself,
VMD doesn't update selections unless you tell it to.

  John Stone

On Fri, Jun 26, 2009 at 03:03:21PM +0200, kumar prashanth wrote:
> Dear VMD experts
> I am working on a lipid bilayer system with large trajectories.
> My original trajectory files have a lot of water and lipid residues.
> I wanted to break down the original trajectories into smaller ones
> containing only a select number of lipids .
> Also the problem I face is that the number of lipid molecules in my
> selection changes for every frame.
> I wanted to use the "animate write dcd my_file_name beg end sel $sel
> waitfor mol_number" command.
> Here,I would like to know whether my sel is automatically updated while
> writing every frame in the new file or I will have to use the $sel
> frame $i and $sel update manually.
> Also,let me know how I can load a trajectory in batches of say 150
> frames ,as VMD crashes while loading most of the trajectory files.
> Regards
> Prashanth.

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