Re: [gmx-users] Using user-tables for simulations in vacuum

2008-07-18 Thread David van der Spoel

sapna sarupria wrote:

Hello,

The simulation does not run even for one step and therefore, it is not 
possible for me to check any of the components such as energy, 
temperature etc. There is no error message except for segmentation 
fault. It does the same thing if I try to energy minimize the system 
instead of running an MD simulation. The corresponding mdp file is 
pasted below:

cpp=  /lib/cpp
constraints =  none
integrator   =  steep
nstcgsteep =  500
emtol =  500.0
emstep =  0.001
vdwtype=  user
energygrps  =  POL
energygrp_table =  POL POL

The commands I use are as follows:
grompp -f em.mdp -p 25mer_wca_vac.top -c 3.5ns.gro
mdrun -s topol.tpr -table table.xvg



Maybe you should make the table way longer. IIRC this is in vacuum with 
no cutoffs. Then the interactions should still fall within the length of 
the table.



Regards
Sapna


On Wed, Jul 16, 2008 at 10:08 AM, David van der Spoel 
[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] wrote:


sapna sarupria wrote:

Hello,

Thanks David for your response. Actually I have used the same
tables for simulations of the polymer in water and have had no
problem with them. Those simulations run for 4 ns without a
problem. So the tables are correct and I am sure of that. I am
not using the CVS version and so I give the energy and second
derivative in the table.  I have used user-defined tables in the
past and so the setup is correct in terms of changing the mdp
file and the top file. The problem seems to be more system
specific (meaning vacuum) than user error specific. Can you
suggest any other thing that may be the problem.

Have you checked energy components, temperature etc.?



Thanks a lot for your help.

Regards
Sapna


On Wed, Jul 16, 2008 at 9:23 AM, David van der Spoel
[EMAIL PROTECTED] mailto:[EMAIL PROTECTED]
mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] wrote:

   sapna sarupria wrote:



   -- Forwarded message --
   From: *sapna sarupria* [EMAIL PROTECTED]
mailto:[EMAIL PROTECTED]
   mailto:[EMAIL PROTECTED]
mailto:[EMAIL PROTECTED]
   mailto:[EMAIL PROTECTED]
mailto:[EMAIL PROTECTED]
mailto:[EMAIL PROTECTED]
mailto:[EMAIL PROTECTED]
   Date: Tue, Jul 15, 2008 at 9:16 AM
   Subject: Using user-tables for simulations in vacuum
   To: Discussion list for GROMACS users
gmx-users@gromacs.org mailto:gmx-users@gromacs.org
   mailto:gmx-users@gromacs.org
mailto:gmx-users@gromacs.org mailto:gmx-users@gromacs.org
mailto:gmx-users@gromacs.org
   mailto:gmx-users@gromacs.org
mailto:gmx-users@gromacs.org


   Hello users,

   I am trying to do a simulation of a polymer chain (which is
   simply a bead of unified methane molecules) in vacuum using
   user-defined tables. The interactions are
   Weeks-Chandler-Andersen instead of Lennard-Jones.
However,  when
   I run the simulations, mdrun gives me a segmentation
fault. When
   I run simulations for the exact same configurations
without the
   tables (and therefore using VdW) the simulations run fine. In
   addition, the starting configurations were obtained after 3ns
   simulations of the polymer in water.

   So I was wondering if there is any issue with using
user-defined
   tables with simulations in vacuum. If not do you have any
idea
   what could be going wrong.
   Some details of the mdp file:
   1. pbc is turned off.
   2. there is no pressure coupling.
   3. center of mass removal is set to angular.
   4. temperature is 298 K and berendsen thermostat is used.
   5. energy groups and table are defined (correctly).
   6. the cut-offs are set to 1.0nm (box size is larger than
4 nm).
   7. no constraints are being used.


   Most obvious error source is the table itself. Do you use the CVS
   version? In that case you should provide energy and force,
otherwise
   energy and second derivative. Distance units are in nm.
Compare to
   existing tables in share/gromacs/top


   Thank you

   Regards
   Sapna



   --Sapna Sarupria
   Ph.D. Student - Chemical Engineering
   Rensselaer Polytechnic Institute
   Troy, New York 12180
   U.S.A.
   Ph#: (518)276-3031
   Life isn't about finding yourself. 

Re: [gmx-users] Using user-tables for simulations in vacuum

2008-07-16 Thread David van der Spoel

sapna sarupria wrote:



-- Forwarded message --
From: *sapna sarupria* [EMAIL PROTECTED] 
mailto:[EMAIL PROTECTED]

Date: Tue, Jul 15, 2008 at 9:16 AM
Subject: Using user-tables for simulations in vacuum
To: Discussion list for GROMACS users gmx-users@gromacs.org 
mailto:gmx-users@gromacs.org



Hello users,

I am trying to do a simulation of a polymer chain (which is simply a 
bead of unified methane molecules) in vacuum using user-defined tables. 
The interactions are Weeks-Chandler-Andersen instead of Lennard-Jones. 
However,  when I run the simulations, mdrun gives me a segmentation 
fault. When I run simulations for the exact same configurations without 
the tables (and therefore using VdW) the simulations run fine. In 
addition, the starting configurations were obtained after 3ns 
simulations of the polymer in water.


So I was wondering if there is any issue with using user-defined tables 
with simulations in vacuum. If not do you have any idea what could be 
going wrong.

Some details of the mdp file:
1. pbc is turned off.
2. there is no pressure coupling.
3. center of mass removal is set to angular.
4. temperature is 298 K and berendsen thermostat is used.
5. energy groups and table are defined (correctly).
6. the cut-offs are set to 1.0nm (box size is larger than 4 nm).
7. no constraints are being used.



Most obvious error source is the table itself. Do you use the CVS 
version? In that case you should provide energy and force, otherwise 
energy and second derivative. Distance units are in nm. Compare to 
existing tables in share/gromacs/top




Thank you

Regards
Sapna



--
Sapna Sarupria
Ph.D. Student - Chemical Engineering
Rensselaer Polytechnic Institute
Troy, New York 12180
U.S.A.
Ph#: (518)276-3031
Life isn't about finding yourself. Life is about creating yourself.
George Bernard Shaw.
Dare to Dream




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--
David van der Spoel, Ph.D., Professor of Biology
Molec. Biophys. group, Dept. of Cell  Molec. Biol., Uppsala University.
Box 596, 75124 Uppsala, Sweden. Phone:  +46184714205. Fax: +4618511755.
[EMAIL PROTECTED]   [EMAIL PROTECTED]   http://folding.bmc.uu.se
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Re: [gmx-users] Using user-tables for simulations in vacuum

2008-07-16 Thread sapna sarupria
Hello,

Thanks David for your response. Actually I have used the same tables for
simulations of the polymer in water and have had no problem with them. Those
simulations run for 4 ns without a problem. So the tables are correct and I
am sure of that. I am not using the CVS version and so I give the energy and
second derivative in the table.  I have used user-defined tables in the past
and so the setup is correct in terms of changing the mdp file and the top
file. The problem seems to be more system specific (meaning vacuum) than
user error specific. Can you suggest any other thing that may be the
problem.

Thanks a lot for your help.

Regards
Sapna


On Wed, Jul 16, 2008 at 9:23 AM, David van der Spoel [EMAIL PROTECTED]
wrote:

 sapna sarupria wrote:



 -- Forwarded message --
 From: *sapna sarupria* [EMAIL PROTECTED] mailto:
 [EMAIL PROTECTED]
 Date: Tue, Jul 15, 2008 at 9:16 AM
 Subject: Using user-tables for simulations in vacuum
 To: Discussion list for GROMACS users gmx-users@gromacs.org mailto:
 gmx-users@gromacs.org


 Hello users,

 I am trying to do a simulation of a polymer chain (which is simply a bead
 of unified methane molecules) in vacuum using user-defined tables. The
 interactions are Weeks-Chandler-Andersen instead of Lennard-Jones. However,
  when I run the simulations, mdrun gives me a segmentation fault. When I run
 simulations for the exact same configurations without the tables (and
 therefore using VdW) the simulations run fine. In addition, the starting
 configurations were obtained after 3ns simulations of the polymer in water.

 So I was wondering if there is any issue with using user-defined tables
 with simulations in vacuum. If not do you have any idea what could be going
 wrong.
 Some details of the mdp file:
 1. pbc is turned off.
 2. there is no pressure coupling.
 3. center of mass removal is set to angular.
 4. temperature is 298 K and berendsen thermostat is used.
 5. energy groups and table are defined (correctly).
 6. the cut-offs are set to 1.0nm (box size is larger than 4 nm).
 7. no constraints are being used.


 Most obvious error source is the table itself. Do you use the CVS version?
 In that case you should provide energy and force, otherwise energy and
 second derivative. Distance units are in nm. Compare to existing tables in
 share/gromacs/top


  Thank you

 Regards
 Sapna



 --
 Sapna Sarupria
 Ph.D. Student - Chemical Engineering
 Rensselaer Polytechnic Institute
 Troy, New York 12180
 U.S.A.
 Ph#: (518)276-3031
 Life isn't about finding yourself. Life is about creating yourself.
 George Bernard Shaw.
 Dare to Dream


 

 ___
 gmx-users mailing listgmx-users@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 [EMAIL PROTECTED]
 Can't post? Read http://www.gromacs.org/mailing_lists/users.php



 --
 David van der Spoel, Ph.D., Professor of Biology
 Molec. Biophys. group, Dept. of Cell  Molec. Biol., Uppsala University.
 Box 596, 75124 Uppsala, Sweden. Phone:  +46184714205. Fax: +4618511755.
 [EMAIL PROTECTED][EMAIL PROTECTED]   http://folding.bmc.uu.se
 ___
 gmx-users mailing listgmx-users@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 [EMAIL PROTECTED]
 Can't post? Read http://www.gromacs.org/mailing_lists/users.php




-- 
Sapna Sarupria
Ph.D. Student - Chemical Engineering
Rensselaer Polytechnic Institute
Troy, New York 12180
U.S.A.
Ph#: (518)276-3031
Life isn't about finding yourself. Life is about creating yourself.
George Bernard Shaw.
Dare to Dream
___
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Please search the archive at http://www.gromacs.org/search before posting!
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Re: [gmx-users] Using user-tables for simulations in vacuum

2008-07-16 Thread David van der Spoel

sapna sarupria wrote:

Hello,

Thanks David for your response. Actually I have used the same tables for 
simulations of the polymer in water and have had no problem with them. 
Those simulations run for 4 ns without a problem. So the tables are 
correct and I am sure of that. I am not using the CVS version and so I 
give the energy and second derivative in the table.  I have used 
user-defined tables in the past and so the setup is correct in terms of 
changing the mdp file and the top file. The problem seems to be more 
system specific (meaning vacuum) than user error specific. Can you 
suggest any other thing that may be the problem.



Have you checked energy components, temperature etc.?




Thanks a lot for your help.

Regards
Sapna


On Wed, Jul 16, 2008 at 9:23 AM, David van der Spoel 
[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] wrote:


sapna sarupria wrote:



-- Forwarded message --
From: *sapna sarupria* [EMAIL PROTECTED]
mailto:[EMAIL PROTECTED]
mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED]
Date: Tue, Jul 15, 2008 at 9:16 AM
Subject: Using user-tables for simulations in vacuum
To: Discussion list for GROMACS users gmx-users@gromacs.org
mailto:gmx-users@gromacs.org mailto:gmx-users@gromacs.org
mailto:gmx-users@gromacs.org


Hello users,

I am trying to do a simulation of a polymer chain (which is
simply a bead of unified methane molecules) in vacuum using
user-defined tables. The interactions are
Weeks-Chandler-Andersen instead of Lennard-Jones. However,  when
I run the simulations, mdrun gives me a segmentation fault. When
I run simulations for the exact same configurations without the
tables (and therefore using VdW) the simulations run fine. In
addition, the starting configurations were obtained after 3ns
simulations of the polymer in water.

So I was wondering if there is any issue with using user-defined
tables with simulations in vacuum. If not do you have any idea
what could be going wrong.
Some details of the mdp file:
1. pbc is turned off.
2. there is no pressure coupling.
3. center of mass removal is set to angular.
4. temperature is 298 K and berendsen thermostat is used.
5. energy groups and table are defined (correctly).
6. the cut-offs are set to 1.0nm (box size is larger than 4 nm).
7. no constraints are being used.


Most obvious error source is the table itself. Do you use the CVS
version? In that case you should provide energy and force, otherwise
energy and second derivative. Distance units are in nm. Compare to
existing tables in share/gromacs/top


Thank you

Regards
Sapna



-- 
Sapna Sarupria

Ph.D. Student - Chemical Engineering
Rensselaer Polytechnic Institute
Troy, New York 12180
U.S.A.
Ph#: (518)276-3031
Life isn't about finding yourself. Life is about creating yourself.
George Bernard Shaw.
Dare to Dream




___
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mailto:gmx-users@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 [EMAIL PROTECTED]
mailto:[EMAIL PROTECTED].
Can't post? Read http://www.gromacs.org/mailing_lists/users.php



-- 
David van der Spoel, Ph.D., Professor of Biology

Molec. Biophys. group, Dept. of Cell  Molec. Biol., Uppsala University.
Box 596, 75124 Uppsala, Sweden. Phone:  +46184714205. Fax: +4618511755.
[EMAIL PROTECTED] mailto:[EMAIL PROTECTED]  
 [EMAIL PROTECTED] mailto:[EMAIL PROTECTED]   http://folding.bmc.uu.se

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--
Sapna Sarupria
Ph.D. Student - Chemical Engineering
Rensselaer Polytechnic Institute
Troy, New York 12180
U.S.A.
Ph#: (518)276-3031
Life isn't about finding yourself. Life is about creating yourself.
George Bernard Shaw.
Dare to Dream




___
gmx-users 

Re: [gmx-users] Using user-tables for simulations in vacuum

2008-07-16 Thread sapna sarupria
Hello,

The simulation does not run even for one step and therefore, it is not
possible for me to check any of the components such as energy, temperature
etc. There is no error message except for segmentation fault. It does the
same thing if I try to energy minimize the system instead of running an MD
simulation. The corresponding mdp file is pasted below:
cpp=  /lib/cpp
constraints =  none
integrator   =  steep
nstcgsteep =  500
emtol =  500.0
emstep =  0.001
vdwtype=  user
energygrps  =  POL
energygrp_table =  POL POL

The commands I use are as follows:
grompp -f em.mdp -p 25mer_wca_vac.top -c 3.5ns.gro
mdrun -s topol.tpr -table table.xvg

Regards
Sapna


On Wed, Jul 16, 2008 at 10:08 AM, David van der Spoel [EMAIL PROTECTED]
wrote:

 sapna sarupria wrote:

 Hello,

 Thanks David for your response. Actually I have used the same tables for
 simulations of the polymer in water and have had no problem with them. Those
 simulations run for 4 ns without a problem. So the tables are correct and I
 am sure of that. I am not using the CVS version and so I give the energy and
 second derivative in the table.  I have used user-defined tables in the past
 and so the setup is correct in terms of changing the mdp file and the top
 file. The problem seems to be more system specific (meaning vacuum) than
 user error specific. Can you suggest any other thing that may be the
 problem.

  Have you checked energy components, temperature etc.?



  Thanks a lot for your help.

 Regards
 Sapna


 On Wed, Jul 16, 2008 at 9:23 AM, David van der Spoel 
 [EMAIL PROTECTED] mailto:[EMAIL PROTECTED] wrote:

sapna sarupria wrote:



-- Forwarded message --
From: *sapna sarupria* [EMAIL PROTECTED]
mailto:[EMAIL PROTECTED]
mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED]
 
Date: Tue, Jul 15, 2008 at 9:16 AM
Subject: Using user-tables for simulations in vacuum
To: Discussion list for GROMACS users gmx-users@gromacs.org
mailto:gmx-users@gromacs.org mailto:gmx-users@gromacs.org
mailto:gmx-users@gromacs.org


Hello users,

I am trying to do a simulation of a polymer chain (which is
simply a bead of unified methane molecules) in vacuum using
user-defined tables. The interactions are
Weeks-Chandler-Andersen instead of Lennard-Jones. However,  when
I run the simulations, mdrun gives me a segmentation fault. When
I run simulations for the exact same configurations without the
tables (and therefore using VdW) the simulations run fine. In
addition, the starting configurations were obtained after 3ns
simulations of the polymer in water.

So I was wondering if there is any issue with using user-defined
tables with simulations in vacuum. If not do you have any idea
what could be going wrong.
Some details of the mdp file:
1. pbc is turned off.
2. there is no pressure coupling.
3. center of mass removal is set to angular.
4. temperature is 298 K and berendsen thermostat is used.
5. energy groups and table are defined (correctly).
6. the cut-offs are set to 1.0nm (box size is larger than 4 nm).
7. no constraints are being used.


Most obvious error source is the table itself. Do you use the CVS
version? In that case you should provide energy and force, otherwise
energy and second derivative. Distance units are in nm. Compare to
existing tables in share/gromacs/top


Thank you

Regards
Sapna



--Sapna Sarupria
Ph.D. Student - Chemical Engineering
Rensselaer Polytechnic Institute
Troy, New York 12180
U.S.A.
Ph#: (518)276-3031
Life isn't about finding yourself. Life is about creating yourself.
George Bernard Shaw.
Dare to Dream



  

___
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mailto:gmx-users@gromacs.org
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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 [EMAIL PROTECTED]
mailto:[EMAIL PROTECTED].
Can't post? Read http://www.gromacs.org/mailing_lists/users.php



--David van der Spoel, Ph.D., Professor of Biology
Molec. Biophys. group, Dept. of Cell  Molec. Biol., Uppsala
 University.
Box 596, 75124 Uppsala, Sweden. Phone:  +46184714205. Fax: +4618511755.
[EMAIL PROTECTED] mailto:[EMAIL PROTECTED]
 [EMAIL PROTECTED] mailto:[EMAIL PROTECTED]   http://folding.bmc.uu.se

[gmx-users] Using user-tables for simulations in vacuum

2008-07-15 Thread sapna sarupria
Hello users,

I am trying to do a simulation of a polymer chain (which is simply a bead of
unified methane molecules) in vacuum using user-defined tables. The
interactions are Weeks-Chandler-Andersen instead of Lennard-Jones. However,
when I run the simulations, mdrun gives me a segmentation fault. When I run
simulations for the exact same configurations without the tables (and
therefore using VdW) the simulations run fine. In addition, the starting
configurations were obtained after 3ns simulations of the polymer in water.

So I was wondering if there is any issue with using user-defined tables with
simulations in vacuum. If not do you have any idea what could be going
wrong.
Some details of the mdp file:
1. pbc is turned off.
2. there is no pressure coupling.
3. center of mass removal is set to angular.
4. temperature is 298 K and berendsen thermostat is used.
5. energy groups and table are defined (correctly).
6. the cut-offs are set to 1.0nm (box size is larger than 4 nm).
7. no constraints are being used.

Thank you

Regards
Sapna
___
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Please search the archive at http://www.gromacs.org/search before posting!
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