[gmx-users] force evaluation

[Florian Dommert]

* Mark Abraham <Mark.Abraham at anu.edu.au> [2009-01-07 00:13:00 +1100]:

> Suman Chakrabarty wrote:
>> On Tue, Jan 6, 2009 at 2:29 PM, Florian Dommert
>> <dommert at fias.uni-frankfurt.de> wrote:
>>>  Finally it would be very interested in a possiblity to switch off the
>>>  vdw interactions easily. So far I used an appropiate topology files with 
>>> C6
>>> and
>>>  C12 set to zero. Is there an easier solution as using a table filled
>>>  with zeros ?
>
> Zeroed tables will be considerably slower than zeroed parameters.
>
> Depending on the way the force field is organized, you might create a 
> version of the force field files that zeroes out these parameters. Another 
> possibility might be to using the preprocessor mechanism to define the VDW 
> parameters only under some circumstances.

Thank you very much for the help. It seems I went the a good way with
using a preprocessing command to define the zero VDW IA.

Now I have to find where the difference in the calculation of the
electrostatic forces. Perhaps somebody can tell me, where the forces get
tabulated, that I can take a look at the code there ?

Cheers,

Flo


>
> Mark
> _______________________________________________
> gmx-users mailing list    gmx-users at gromacs.org
> http://www.gromacs.org/mailman/listinfo/gmx-users
> Please search the archive at http://www.gromacs.org/search before posting!
> Please don't post (un)subscribe requests to the list. Use the www interface 
> or send it to gmx-users-request at gromacs.org.
> Can't post? Read http://www.gromacs.org/mailing_lists/users.php

-- 
Florian Dommert
Dipl.-Phys.

Computational and Theoretical Softmatter & Biophysics group

Frankfurt Institute for Advanced Studies
Johann-Wolfgang-Goethe University

Ruth-Moufang-Str. 1
60438 Frankfurt am Main

Phone: +49(0)69 / 798 - 47529
Fax:   +49(0)69 / 798 - 47611

EMail: dommert at fias.uni-frankfurt.de
Home: http://fias.uni-frankfurt.de/~simbio/Florian_Dommert
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 194 bytes
Desc: not available
URL: <http://maillist.sys.kth.se/pipermail/gromacs.org_gmx-users/attachments/20090106/e1d6762b/attachment.sig>