Reply To: random seed

[Ora Furman]

If you run jobs in a cluster of parallel cpus,sometimes you will get exact same results.This is a general problem for Rosetta.The reason is that some cpus are starting from exactly the same random seed .One solution for this is to add -seed_offset followed by an int number to your command line ,in this way, you can force each cpu to start from a different seed with that offset number.
You can also try to run with -constant_seed -jran in multiple clusters,yes, the selection of the integers for the jran should between 1 million and 4 million.The default value is 1111111.You can certainly choose different values if you want to submit jobs to different clusters.

> Hi,
>
> First sorry for repeating this question but I really need to get straight with randomness in rosetta and it would be great to have a good explanation of that somewhere on the web, for example on this forum.
>
> I want to run multiple rosetta instances for the same protein on several computer clusters. From the manual and previous posts I can see two options:
> 1) -constant_seed -jran
> 2) -seed_offset
>
> Which one is better? I think the commonly used is option 1). But how this differs from 2) ? Does they do the same?
>
> Is there any constraint on selection of the particular integers from 1 000 000 to 4 000 000 in -jran? If I am to submit 100 jobs on cluster 1 and 100 jobs on cluster 2 I can just simply use 1 000 000 to 1 000 099 on cluster 1 and 1 000 100 to 1 000 199 on cluster 2? Or is it more sophisticated?
>
> Thanks for your help,
>
> Janek Kosinski