On Thu, Dec 11, 2025, Emme Burgin via AMBER wrote:
>I am trying to apply a modification to the weights of an NMR restraint in
>a DISANG file using an &wt nameless with type=‘rest’. This works just
>fine in Amber22 sander and pmemd, but in pmemd.cuda it quietly fails
>to apply the weight changes. The weight changes are read in and described
>correctly in the output file, and the simulation proceeds, but the weight
>changes are not applied. I’ve attached the output files from some test
>simulations (if that works), but here are some relevant sections. The input
>file in each case is the same, with an &wt namelist that should turn off
>the restraints completely:
>
> Here is the input file:
>
> &wt
> type="REST",
> value1=0, value2=0,
> istep1=0, istep2=2500,
> /
It's certainly possible that the "REST" keyword is not being correctly
recognized by pmemd.cuda. Since your restraints seem to be bonds, see if
changing "REST" to "BOND" makes any difference.
Also, setting both value1 and value2 to zero effectively turns off all
restraints -- is that what you want? Is that what you see when running the
CPU versions? See what happens if you may value1 and value2 different.
I'm pretty sure the REST keyword is very rarely used, so there could be some
problem there. But try to play around with variations in your input to see
if one can narrow things down.
...good luck...dac
_______________________________________________
AMBER mailing list
AMBER.ambermd.org
http://lists.ambermd.org/mailman/listinfo/amber
Received on Sat Dec 13 2025 - 09:00:02 PST
