[gmx-developers] REMD and network.c

[David van der Spoel]

On 3/19/10 4:05 PM, alberto wrote:
> Hi Developers,
> I'm trying to run REMD with current git versions and I'm finding some problems.
> It seems that the replica parameters for seed and temperature (repl_ex.c) loose
> their real values when passing through gmx_sumi_sim   (seed) and gmx_sum_sim
> (Temperatures) in network.c

Can you specify how you are running?
One cpu per replica or more than one?

> This produces errors when trying to interchange replicas (each replica runs
> normal MD at correct temperature until the exchange point):
>
> Repl      1     0
> Repl  T   0.0 396316835928080384.0
> Repl
> Repl  exchange interval: 1000
>
> Repl  random seed: 0
> Repl  below: x=exchange, pr=probability
>
> [sim runs fine until first step in which it has to exchange]
>
> Replica exchange at step 1000 time 2
> Repl 1<->  0  dE =       -inf
>
> Here is the output for the same input when running with the latest stable
> version (4.07)
>
> Repl      0     1
> Repl  T 300.0 315.0
> Repl
> Repl  exchange interval: 1000
>
> Repl  random seed: 954549
> Repl  below: x=exchange, pr=probability
> [and everything runs perfect]
>
> Unfortunately I can't really see how to fix it and have not seen any post on the
> subject,
> thanks for your help,
> Alberto
>
>


-- 
David.
________________________________________________________________________
David van der Spoel, PhD, Professor of Biology
Dept. of Cell and Molecular Biology, Uppsala University.
Husargatan 3, Box 596,  	75124 Uppsala, Sweden
phone:	46 18 471 4205		fax: 46 18 511 755
spoel at xray.bmc.uu.se	spoel at gromacs.org   http://folding.bmc.uu.se
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++