Bug #385
integrator = steep; nsteps = 0 runs an infinite number of steps
Description
Perhaps this is a feature, rather than a bug, and I can see why one would want to do this some times. However, the behaviour does not match up with integrator = md; nsteps = 0, for which a zero-step run is actually completed.
In any event, I could not find any documentation for this in the online or pdf manual.
History
#1 Updated by Erik Lindahl over 10 years ago
Hi Chris,
I do indeed think it's a "feature"; for a while it was present for integrator=md too, but there I reverted it since I frequently use nsteps=0 for testing energies/forces.
David/Berk: Unless you protest, I think we should change it so "0" means a single potential evaluation,but no steps, and use e.g. "-1" to mean "run forever".
Cheers,
Erik
#2 Updated by Chris Neale over 10 years ago
I think that is a great idea. It would be even better if this became generally true such that md, bd, and sd also run forever if nsteps=-1 (not currently possible as far as I know) and simply do the energy evaluation with no steps if nsteps=0 (currently true).
#3 Updated by Berk Hess over 10 years ago
I wonder if all the minimizers currently behave the same with nsteps=0 or 1.
But I agree with implemented the ideas for nsteps=0 and nsteps=1.
Especially with the current -maxh feature is it useful to have an
unlimited amount of steps.
Berk
#4 Updated by David van der Spoel almost 10 years ago
Has Erik's idea been implemented?
#5 Updated by Berk Hess almost 10 years ago
I implemented nsteps=0 is 0 steps, nsteps=-1 is unlimited.
-maxh does not work for the minimizers, but I guess that in most
cases you will reach machine precision limits quite soon.
Berk