[gmx-users] Trouble with restrained dihedrals

[David van der Spoel]

Den 2020-04-16 kl. 08:56, skrev Marko Petrovic:
> Hello
> 
> I'm trying to run an Energy Minimisation run while restraining phi and psi of the central alanine of an alanine dipeptide in vacuum. Hopefully it won't make a difference if I run a EM equilibration or other run for this error/concept since I am trying to create a script for creating/updating the necessary files for several different simulation runs.
> 
> The error message:
> ERROR 1 [file cv_restraints.itp, line 3]:
>    Incorrect number of parameters - found 5, expected 3 or 6 for Dih. Rest.
>    (after the function type).
> 
> The .itp file contents:
> [ dihedral_restraints ]
> ; ai   aj   ak   al  type  label  phi  dphi  kfac  power
>           5         7         9        15         1         1   -67.652   0   1   2

>           7         9        15        17         1         1    59.806   0   1   2

Not sure where you have this format from but it should be

; ai   aj   ak   al  type  phi  dphi  kfac


> 
> Other possibly relevant file snippets:
> .mdp file define row (1st row):
> define                    = -DPOSRES_CV
> 
> topol.top ifdef statement (last in file):
> #ifdef POSRES_CV
> #include "cv_restraints.itp"
> #endif
> 
> I hope this is the info needed to easily see what I've done wrong. (Also info on how to interpret the error message would be nice, like which 5 parameters the software found and how it coun'ts parameters so I can get them to 3 or 6 if the problem is in the .utp file)
> 
> With Regards
> Marko Petrovic
> Educator
> Computational Science and Technology
> School of Electrical Engineering and Computer Science
> KTH Royal Institute of Technology
> 


-- 
David van der Spoel, Ph.D.,
Professor of Biology
Uppsala University.
http://virtualchemistry.org