Subject: Re: CCL:md rookie update

From: Konrad Hinsen <[email-masked]>
Date: Thu, 8 Jan 1998 13:50:36 +0100

> The dcd trajectory format is machine-dependant; there is a other-endian
> filter out there which I haven't been able to get to work, however.

The Molecular Modelling Toolkit (MMTK), available at
http://starship.skyport.net/crew/hinsen/mmtk.html, allows conversion
of DCD files into machine-independent netCDF files. The inverse
conversion is not yet implemented, but MMTK contains plenty of
analysis functions to do whatever you want with the netCDF trajectory
files.
-- 
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Konrad Hinsen                          | E-Mail: [email-masked]
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From: Leif Laaksonen <[email-masked]>
Date: Thu, 8 Jan 1998 16:04:17 +0200 (GFT Standard Time)

Hi,

If you aren't worried about loosing the last decimal of the accuracy you
can use my small FORTRAN program for CHARMM trajectories for the
formatting/unformatting at: 

http://laaksonen.csc.fi/gopenmol/distribute/linux/charmmtrj.f

I mostly use the program to move the trajectories between different
types of machines.

Regards,

-leif laaksonen

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On Thu, 8 Jan 1998, Konrad Hinsen wrote:

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From: Rick Venable <[email-masked]>
Date: Thu, 8 Jan 1998 12:49:08 -0500 (EST)

> I mostly use the program to move the trajectories between different

Of course, if you're actually using CHARMM, you can use the built-in FORMAT
and UNFORMAT commands to move CHARMM trajectories across machines types
(whether you call them .dcd or .trj files).  It's a feature that's been
available for well over a decade, since the differences in machine dependent
floating point representations were even greater in the past.  It allows
the user some control over the precision, by changing some of the scaling and
the Z format specs (Fortran zoned-hexadeciamal format).

I should add that, besides big-endian and little-endian IEEE f.p.
representations, there can be file structure differences between platforms as
well.  The Fortran standard does not define the structure of a binary file on
disk, only the results of READ and WRITE operations; the details can be
machine dependent.  

--
Rick Venable                  =====\     |=|    "Eschew Obfuscation"
FDA/CBER Biophysics Lab       |____/     |=|
Bethesda, MD  U.S.A.          |   \    / |=|  ( Not an official statement or
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