[gmx-users] strange behaviout in 5.1.2

[Justin Lemkul]

On 2/5/16 11:37 AM, Kortzak, Daniel wrote:
> Dear All,
>
> when using gmx-5.1.2 with a mdp file with the following pressure coupling parameters:
>
> ; pressure coupling
> Pcoupl                   = berendsen
> Pcoupltype               = semiisotropic
> nstpcouple               = -1
> ; Time constant (ps), compressibility (1/bar) and reference P (bar)
> tau_p                    = 5 5
> compressibility          = 4.5e-5 4.5e-5
> ref_p                    = 1.0 1.0
> ; Scaling of reference coordinates, No, All or COM
> refcoord_scaling         = all
>
>
> grompp gives the error message:
>
>
> ERROR 1 [file parameter.mdp, line 387]:
>    Right hand side '5 5' for parameter 'tau_p' in parameter file is not a
>    real value
>
>
> With versions below 5.1.2 everything seems to be fine. Are there additional changes beyond what is mentioned in the release notes or am I to blind to find the right section?
>

tau_p only takes one value (unlike tau_t, which needs one per thermostat group). 
  The issue that was fixed was grompp silently ignoring extraneous input values, 
so previous versions carry on happily ignoring the stuff it doesn't need.

http://manual.gromacs.org/documentation/5.1.2/ReleaseNotes/release-notes.html#fix-grompp-not-warning-when-mdp-values-have-wrong-types

-Justin

-- 
==================================================

Justin A. Lemkul, Ph.D.
Ruth L. Kirschstein NRSA Postdoctoral Fellow

Department of Pharmaceutical Sciences
School of Pharmacy
Health Sciences Facility II, Room 629
University of Maryland, Baltimore
20 Penn St.
Baltimore, MD 21201

jalemkul at outerbanks.umaryland.edu | (410) 706-7441
http://mackerell.umaryland.edu/~jalemkul

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