Re: [gmx-users] itp atomtypes section

2012-11-27 Thread Tsjerk Wassenaar
Hi James,

The 6 and 1 are the number of electrons the atomtype has, which is used for
QM/MM stuff. Gromacs can tell whether or not it is given by checking the
format of the line. If the 5th column is a letter, then the number isn't
there, if the 6th column is a letter, it must be there.

Hope it helps,

Tsjerk


On Tue, Nov 27, 2012 at 3:45 AM, James Cannon jamesresearch...@gmail.comwrote:

 Dear users,

 I apologise if this is a stupid question, however after a morning of
 searching I have not been able to find the answer.

 1. I have a sample itp file and it contains a section like this:
 [ atomtypes ]
 CF  CF  6  12.011000.2588   A3.5e-01  2.56134e-01
 HF  HF  1   1.008000.1000   A3.5e-01  4.28529e-01

 I can't work out what the column containing the 6 and 1 is for. Can
 anyone help? It's not documented anywhere that I can find.



 2. I notice that there are many types of atomtypes fields. From the
 manual:
 [ atomtypes ]
 ;name mass charge ptype c6 c12
 O 15.99940 0.000 A 0.22617E-02 0.74158E-06
 OM 15.99940 0.000 A 0.22617E-02 0.74158E-06

 This is clearly a different format to my sample above. Why does the format
 vary? I know the above format is not wrong because it runs succcessfully in
 a test-run. How does gromacs know which format to use correctly?

 I appreciate any help.
 Thank you.
 Best regards,

 James
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[gmx-users] error during minimization

2012-11-27 Thread Shine A
Sir,

   I am studying the dynamics of membrane proteins using KALP-15 in DPPC.
But during minimization (after shrinking), getting error like this.
 Fatal error:
 Invalid line in system_shrink26.gro for atom 8703:
6.4140   6.44350  6.59650.why this error?plz give me a solution to
overcome it.
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Re: [gmx-users] error during minimization

2012-11-27 Thread Venkat Reddy
Probably..there is a problem in spacing at the bottom of your gro file. The
line mentioning the vectors should be like this
eg:,

5012OBC49   47   1.088   1.094   2.775

   0.0   0.0   0.0


On Tue, Nov 27, 2012 at 3:01 PM, Shine A shin...@iisertvm.ac.in wrote:

 Sir,

I am studying the dynamics of membrane proteins using KALP-15 in DPPC.
 But during minimization (after shrinking), getting error like this.
  Fatal error:
  Invalid line in system_shrink26.gro for atom 8703:
 6.4140   6.44350  6.59650.why this error?plz give me a solution to
 overcome it.
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With Best Wishes
Venkat Reddy Chirasani
PhD student
Laboratory of Computational Biophysics
Department of Biotechnology
IIT Madras
Chennai
INDIA-600036
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Re: [gmx-users] error during minimization

2012-11-27 Thread Justin Lemkul



On 11/27/12 4:31 AM, Shine A wrote:

Sir,

I am studying the dynamics of membrane proteins using KALP-15 in DPPC.
But during minimization (after shrinking), getting error like this.
  Fatal error:
  Invalid line in system_shrink26.gro for atom 8703:
 6.4140   6.44350  6.59650.why this error?plz give me a solution to
overcome it.



The program is complaining that it is looking for an atom and finding box 
vectors.  That indicates a mismatch between the number of atoms (specified on 
the second line of the .gro file) and the actual number of atoms.


-Justin

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Department of Biochemistry
Virginia Tech
Blacksburg, VA
jalemkul[at]vt.edu | (540) 231-9080
http://www.bevanlab.biochem.vt.edu/Pages/Personal/justin


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Re: [gmx-users] g_select error

2012-11-27 Thread Albert

hello Justin:

  thanks for kind tips.
  I've tried both methods:

g_select -f md.xtc -s npt3.pdb -os size.xvg -sf selection.dat

g_select -f md.xtc -s npt3.pdb -os size.xvg -select 'resname SOL and 
name OW within 0.6 of resid 114'



but they all failed with messages:

log

WARNING: masses and atomic (Van der Waals) radii will be determined
 based on residue and atom names. These numbers can deviate
 from the correct mass and radius of the atom type.

selection parser: syntax error
selection parser: invalid selection 'resname SOL and name OW within 0.6 
of resid 114'


---
Program g_select, VERSION 4.5.5
Source code file: trajana.c, line: 1310

Input error or input inconsistency:
selection(s) could not be parsed
For more information and tips for troubleshooting, please check the GROMACS
website at http://www.gromacs.org/Documentation/Errors
---

Yeah, a Wuzz, Or a Jerk (F. Black)






On 11/27/2012 01:54 AM, Justin Lemkul wrote:



On 11/26/12 2:08 PM, Albert wrote:


hello:

  I am going to calculate the number of water molecules within 6 A of
residue 114 by following command:


g_select -f md.xtc -s npt3.pdb -os size.xvg -select resid 114 and rdist
 0.6


but it said:


WARNING: masses and atomic (Van der Waals) radii will be determined
  based on residue and atom names. These numbers can deviate
  from the correct mass and radius of the atom type.

selection parser: syntax error
selection parser: invalid selection 'resid 114 and rdist  0.6'

---
Program g_select, VERSION 4.5.5
Source code file: trajana.c, line: 1310

Input error or input inconsistency:
selection(s) could not be parsed
For more information and tips for troubleshooting, please check the 
GROMACS

website at http://www.gromacs.org/Documentation/Errors
---



You haven't defined rdist to actually be anything.  If you need to be 
using multi-line selections, you should be providing a selection.dat 
file to -sf instead of using single-line statements to -select.


Something like g_select -select 'resname SOL and name OW within 0.6 of 
resid 114' should do the trick, but I haven't actually tried that so 
I'm not 100% sure.


-Justin



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Re: [gmx-users] g_select error

2012-11-27 Thread Justin Lemkul



On 11/27/12 9:18 AM, Albert wrote:

hello Justin:

   thanks for kind tips.
   I've tried both methods:

g_select -f md.xtc -s npt3.pdb -os size.xvg -sf selection.dat

g_select -f md.xtc -s npt3.pdb -os size.xvg -select 'resname SOL and name OW
within 0.6 of resid 114'


but they all failed with messages:

log

WARNING: masses and atomic (Van der Waals) radii will be determined
  based on residue and atom names. These numbers can deviate
  from the correct mass and radius of the atom type.

selection parser: syntax error
selection parser: invalid selection 'resname SOL and name OW within 0.6 of resid
114'

---
Program g_select, VERSION 4.5.5
Source code file: trajana.c, line: 1310

Input error or input inconsistency:
selection(s) could not be parsed
For more information and tips for troubleshooting, please check the GROMACS
website at http://www.gromacs.org/Documentation/Errors
---



Well, like I warned, I wasn't 100% sure of the syntax, so it was no guarantee 
that I was right.  Reading into the documentation and examples a bit, it seems 
that resname SOL and name OW should be enclosed within double quotes, within 
the single-quoted string.  Otherwise, use this selection.dat file:


waterO = name OW;
close = waterO and within 0.6 of resid 114;
close;

It should be possible to do it in one line, but the above set of selections 
seems to work fine.


-Justin

--


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Research Scientist
Department of Biochemistry
Virginia Tech
Blacksburg, VA
jalemkul[at]vt.edu | (540) 231-9080
http://www.bevanlab.biochem.vt.edu/Pages/Personal/justin


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Re: [gmx-users] g_select error

2012-11-27 Thread Albert

On 11/27/2012 03:33 PM, Justin Lemkul wrote:
Well, like I warned, I wasn't 100% sure of the syntax, so it was no 
guarantee that I was right.  Reading into the documentation and 
examples a bit, it seems that resname SOL and name OW should be 
enclosed within double quotes, within the single-quoted string. 
Otherwise, use this selection.dat file:


waterO = name OW;
close = waterO and within 0.6 of resid 114;
close;

It should be possible to do it in one line, but the above set of 
selections seems to work fine.


-Justin


thank you so much for such kind helps.
it finally works.;-)

best
Albert
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[gmx-users] g_bar and second law violations

2012-11-27 Thread Sanku M
Hi,
  I am trying to compute the free energy change using g_bar: I am using 
two-stage decoupling process as in Justin Lemkul's tutorial.
But , I get following warning in all cases regarding violation of second law of 
thermodynamics. Can someone explain what is this error about and which lambda I 
should look for?
Here is the output.

 Detailed results in kT (see help for explanation):

 lam_A  lam_B      DG   +/-     s_A   +/-     s_B   +/-   stdev   +/- 
 0.000  0.100   -0.39  0.08   -0.64  0.06   -0.09  0.20    0.88  0.05
 0.100  0.150    0.08  0.04    0.07  0.03    0.09  0.05    0.43  0.01
 0.150  0.200    0.12  0.02   -0.11  0.03    0.36  0.06    0.54  0.02
 0.200  0.300    0.54  0.06   -0.05  0.07    1.25  0.15    1.24  0.03
 0.300  0.350    0.21  0.03    0.15  0.04    0.31  0.06    0.72  0.01
 0.350  0.400   -0.01  0.02    0.11  0.03   -0.08  0.04    0.64  0.01
 0.400  0.500   -0.37  0.03    0.22  0.02   -0.78  0.06    1.07  0.01
 0.500  0.600   -0.58  0.01    0.17  0.04   -1.17  0.04    0.99  0.01
 0.600  0.700   -0.74  0.03    0.16  0.02   -1.51  0.07    0.89  0.01
 0.700  0.750   -0.37  0.01   -0.02  0.02   -0.69  0.03    0.47  0.01
 0.750  0.800   -0.26  0.01   -0.07  0.01   -0.42  0.02    0.53  0.01
 0.800  0.850   -0.19  0.01    0.03  0.01   -0.38  0.03    0.57  0.01
 0.850  0.900   -0.24  0.02    0.06  0.01   -0.50  0.04    0.58  0.01
 0.900  1.000   -0.47  0.07   -0.04  0.05   -0.12  0.34    1.13  0.06

WARNING: Some of these results violate the Second Law of Thermodynamics: 
         This is can be the result of severe undersampling, or (more likely)
         there is something wrong with the simulations.


Final results in kJ/mol:

lambda  0.000 -  0.100,   DG -0.97 +/-  0.19
lambda  0.100 -  0.150,   DG  0.20 +/-  0.09
lambda  0.150 -  0.200,   DG  0.30 +/-  0.05
lambda  0.200 -  0.300,   DG  1.34 +/-  0.15
lambda  0.300 -  0.350,   DG  0.52 +/-  0.07
lambda  0.350 -  0.400,   DG -0.02 +/-  0.05
lambda  0.400 -  0.500,   DG -0.92 +/-  0.08
lambda  0.500 -  0.600,   DG -1.45 +/-  0.03
lambda  0.600 -  0.700,   DG -1.86 +/-  0.08
lambda  0.700 -  0.750,   DG -0.91 +/-  0.03
lambda  0.750 -  0.800,   DG -0.64 +/-  0.03
lambda  0.800 -  0.850,   DG -0.48 +/-  0.03
lambda  0.850 -  0.900,   DG -0.61 +/-  0.04
lambda  0.900 -  1.000,   DG -1.17 +/-  0.18

total   0.000 -  1.000,   DG -6.68 +/-  0.30
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[gmx-users] how to run charmm2gromacs-pvm.py correctly?

2012-11-27 Thread Albert

Hello:

I am trying to convert the output from CGenFF website into Gromacs .itp 
format by command:


python charmm2gromacs-pvm.py charmm.rst

but it said:


Traceback (most recent call last):
  File charmm2gromacs-pvm.py, line 33, in module
parFile = open(sys.argv[2], 'r')
IndexError: list index out of range



I open the script, it said:

inparameters:
command line parameters:
1charmm topology file
2corresponding charmm parameter file
3optfoldername, default cgenff.ff

outfiles:
1foldername/atomtypes.atp
2foldername/forcefield.itp
3foldername/forcefield.doc
4foldername/aminoacids.rtp
5foldername/ffbonded.itp
6foldername/ffnonbonded.itp
7foldername/forcefield.r2b
8optfoldername/lipids.rtp(if '!lipid 
section' statement in CHARMM top file)

9optfoldername/cmap.itp(if genCMAP = True)


It seems that the input file is a folder instead of a single file? I 
generate my ligand topology from the CGenFF website and I only get a 
.rst file


THX
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[gmx-users] Fwd: Validation of topology ....

2012-11-27 Thread rama david
Dear Gromacs friends,
 I want to simulate a system containing the biotin.
I get the topology from ATB.
   I want to validate these toplogy for my use .
So please could some one told me the way how I can do it ??
I never had any such experience.
Is these is any tutorial regarding to these.
These is most difficult but needed things in MD.

With best wishes and regards,
Rama David.
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Re: [gmx-users] how to run charmm2gromacs-pvm.py correctly?

2012-11-27 Thread David van der Spoel

On 2012-11-27 17:58, Albert wrote:

Hello:

I am trying to convert the output from CGenFF website into Gromacs .itp
format by command:

python charmm2gromacs-pvm.py charmm.rst


you need an extra file. IIRC the cgenff method gives you two files.




but it said:


Traceback (most recent call last):
   File charmm2gromacs-pvm.py, line 33, in module
 parFile = open(sys.argv[2], 'r')
IndexError: list index out of range



I open the script, it said:

inparameters:
 command line parameters:
 1charmm topology file
 2corresponding charmm parameter file
 3optfoldername, default cgenff.ff

outfiles:
 1foldername/atomtypes.atp
 2foldername/forcefield.itp
 3foldername/forcefield.doc
 4foldername/aminoacids.rtp
 5foldername/ffbonded.itp
 6foldername/ffnonbonded.itp
 7foldername/forcefield.r2b
 8optfoldername/lipids.rtp(if '!lipid
section' statement in CHARMM top file)
 9optfoldername/cmap.itp(if genCMAP = True)


It seems that the input file is a folder instead of a single file? I
generate my ligand topology from the CGenFF website and I only get a
.rst file

THX



--
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Dept. of Cell  Molec. Biol., Uppsala University.
Box 596, 75124 Uppsala, Sweden. Phone:  +46184714205.
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Re: [gmx-users] itp atomtypes section

2012-11-27 Thread James Cannon
Dear Tsjerk,

Thanks for clarifying that for me. I appreciate it.

Best regards,

James


On Tue, Nov 27, 2012 at 5:25 PM, Tsjerk Wassenaar tsje...@gmail.com wrote:

 Hi James,

 The 6 and 1 are the number of electrons the atomtype has, which is used for
 QM/MM stuff. Gromacs can tell whether or not it is given by checking the
 format of the line. If the 5th column is a letter, then the number isn't
 there, if the 6th column is a letter, it must be there.

 Hope it helps,

 Tsjerk


 On Tue, Nov 27, 2012 at 3:45 AM, James Cannon jamesresearch...@gmail.com
 wrote:

  Dear users,
 
  I apologise if this is a stupid question, however after a morning of
  searching I have not been able to find the answer.
 
  1. I have a sample itp file and it contains a section like this:
  [ atomtypes ]
  CF  CF  6  12.011000.2588   A3.5e-01  2.56134e-01
  HF  HF  1   1.008000.1000   A3.5e-01  4.28529e-01
 
  I can't work out what the column containing the 6 and 1 is for. Can
  anyone help? It's not documented anywhere that I can find.
 
 
 
  2. I notice that there are many types of atomtypes fields. From the
  manual:
  [ atomtypes ]
  ;name mass charge ptype c6 c12
  O 15.99940 0.000 A 0.22617E-02 0.74158E-06
  OM 15.99940 0.000 A 0.22617E-02 0.74158E-06
 
  This is clearly a different format to my sample above. Why does the
 format
  vary? I know the above format is not wrong because it runs succcessfully
 in
  a test-run. How does gromacs know which format to use correctly?
 
  I appreciate any help.
  Thank you.
  Best regards,
 
  James
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 --
 Tsjerk A. Wassenaar, Ph.D.

 post-doctoral researcher
 Biocomputing Group
 Department of Biological Sciences
 2500 University Drive NW
 Calgary, AB T2N 1N4
 Canada
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[gmx-users] Gromacs 4.6 segmentation fault with mdrun

2012-11-27 Thread Makoto Yoneya
Dear GROMACS users:

On Gromacs 4.6 segmentation fault with mdrun,
I'd also met the same segmentation fault problem with gromacs-4.6.
on my linux box with GTX-580.
For my case, change the compilor solved this problem.

Raf Ponsaerts wrote he used

 gcc 4.4.5 (Debian 4.4.5-8), Linux kernel 3.1.1
 CMake 2.8.7 .

These were same in the version when I first met the problem.
After that, I'd tried Intel compilor instead of gcc-4.4.x,
then the GPU jobs runs without the segmentation fault.
I also tried gcc-4.6.x and it also runs without
any faults (I'm using CentOS and its gcc version is currentry
gcc-4.4.x. Then, I had to compile gcc-4.6.x from the source.
gcc-4.7.x can't use with CUDA-4.2 since it only suppoorts
up to gcc-4.6.x.).

I suggest to try either intel compilor or gcc-4.6.x instead of
gcc-4.4.x.

Makoto Yoneya, Dr.
AIST, Japan
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Re: [gmx-users] g_bar and second law violations

2012-11-27 Thread Justin Lemkul



On 11/27/12 11:43 AM, Sanku M wrote:

Hi,
   I am trying to compute the free energy change using g_bar: I am using 
two-stage decoupling process as in Justin Lemkul's tutorial.
But , I get following warning in all cases regarding violation of second law of 
thermodynamics. Can someone explain what is this error about and which lambda I 
should look for?
Here is the output.



You can't have negative entropy.  Several of your simulation windows do, which 
indicates some severe problem, as the error suggests.


-Justin


  Detailed results in kT (see help for explanation):

  lam_A  lam_B  DG   +/- s_A   +/- s_B   +/-   stdev   +/-
  0.000  0.100   -0.39  0.08   -0.64  0.06   -0.09  0.200.88  0.05
  0.100  0.1500.08  0.040.07  0.030.09  0.050.43  0.01
  0.150  0.2000.12  0.02   -0.11  0.030.36  0.060.54  0.02
  0.200  0.3000.54  0.06   -0.05  0.071.25  0.151.24  0.03
  0.300  0.3500.21  0.030.15  0.040.31  0.060.72  0.01
  0.350  0.400   -0.01  0.020.11  0.03   -0.08  0.040.64  0.01
  0.400  0.500   -0.37  0.030.22  0.02   -0.78  0.061.07  0.01
  0.500  0.600   -0.58  0.010.17  0.04   -1.17  0.040.99  0.01
  0.600  0.700   -0.74  0.030.16  0.02   -1.51  0.070.89  0.01
  0.700  0.750   -0.37  0.01   -0.02  0.02   -0.69  0.030.47  0.01
  0.750  0.800   -0.26  0.01   -0.07  0.01   -0.42  0.020.53  0.01
  0.800  0.850   -0.19  0.010.03  0.01   -0.38  0.030.57  0.01
  0.850  0.900   -0.24  0.020.06  0.01   -0.50  0.040.58  0.01
  0.900  1.000   -0.47  0.07   -0.04  0.05   -0.12  0.341.13  0.06

WARNING: Some of these results violate the Second Law of Thermodynamics:
  This is can be the result of severe undersampling, or (more likely)
  there is something wrong with the simulations.


Final results in kJ/mol:

lambda  0.000 -  0.100,   DG -0.97 +/-  0.19
lambda  0.100 -  0.150,   DG  0.20 +/-  0.09
lambda  0.150 -  0.200,   DG  0.30 +/-  0.05
lambda  0.200 -  0.300,   DG  1.34 +/-  0.15
lambda  0.300 -  0.350,   DG  0.52 +/-  0.07
lambda  0.350 -  0.400,   DG -0.02 +/-  0.05
lambda  0.400 -  0.500,   DG -0.92 +/-  0.08
lambda  0.500 -  0.600,   DG -1.45 +/-  0.03
lambda  0.600 -  0.700,   DG -1.86 +/-  0.08
lambda  0.700 -  0.750,   DG -0.91 +/-  0.03
lambda  0.750 -  0.800,   DG -0.64 +/-  0.03
lambda  0.800 -  0.850,   DG -0.48 +/-  0.03
lambda  0.850 -  0.900,   DG -0.61 +/-  0.04
lambda  0.900 -  1.000,   DG -1.17 +/-  0.18

total   0.000 -  1.000,   DG -6.68 +/-  0.30



--


Justin A. Lemkul, Ph.D.
Research Scientist
Department of Biochemistry
Virginia Tech
Blacksburg, VA
jalemkul[at]vt.edu | (540) 231-9080
http://www.bevanlab.biochem.vt.edu/Pages/Personal/justin


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[gmx-users] Re: About Temperature coupling and Energy Transfer....

2012-11-27 Thread cyberjhon
Dear Justin

Thanks for your answer.

I know what you mean, but the problem is that this is not 
a possible physical (real) behaviour.

If the temperature is not controlled as you said, the energy should continue 
growing not stop, but in these case after 50ps it reaches some kind of
equilibrium 
and stabilize. 

So why this is happening? Can you give me with a Physical or
and Algorithmic answer?

Thanks

John Michael



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Re: [gmx-users] About the biotin parameter.....

2012-11-27 Thread rama david
Hi justin,

Thank you for your suggestion.

I read the ATB paper but the paper does not mention any thing related to
the biotin.

When I mail them, they replied ..

To clarify the validation:
There are different levels of validation criteria used in the ATB.
The one which is available on the ATB web-site for a given molecule is the
validation of the topology against the compatibility with the GROMOS force
field. The output contains energies for bonded parameters.
The validation described in the paper is the validation against the
experimental hydration free energy of small organic molecules. Biotin was
not a part of the validation dataset.


What should I have to do..???
Please give me the suggestion.

With best wishes and regards,
Rama david
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