Re: [h5md-user] The first H5MD modules: "particles" and "observables"

[Felix Höfling]

Am 07.10.2013, 11:52 Uhr, schrieb Konrad Hinsen
<address@hidden>:

> Pierre de Buyl writes:
>
>  > I would prefer very much that the current spec does not rely on  
> additional
>  > modules, however standard those modules are.
>  >
>  > The spec is clear that a lot is optional. I feel that making  
> /particles and
>  > /observables part of a module would void H5MD of much of its purpose.
>
>
> Felix Höfling writes:
>
>  > The two modules would be part of the H5MD spec, of course. The two  
> root
>  > groups are optional anyway. We would not loose anything by calling  
> them
>  > "modules" IMHO.
>  >
>  > My concern is the following: "particles" and "observables" are not
>  > distinguished in the set of possible modules, but take a distinguished
>  > place in the spec now. Think about lattice-Boltzmann simulations: why  
> are
>  > lattice data qualified as "module", but particle positions in the
>  > continuum belong to the core specification? Or why are time-series  
> data
>  > (in observables) "better" than a pair distribution function or a
>  > mean-square displacement?
>
>
> Let me take my pragmatist's role again and ask the question: what
> difference does it make whether "particles" and "observables" are
> part of the core definition, or optional modules?
>
> The only difference I see is that in the first case, the two groups
> must exist even if they are empty, whereas in the second case one or
> the other may be missing completely.
>
> If that's indeed the only practical difference, I suggest throwing
> a coin to settle the issue and move on to more important subjects.
>
> Konrad.

Actually, both groups are optional in the current draft. There is _no_
difference whether we call them modules or not. It is just a matter of how
the H5MD spec is presented. Calling them modules would be clearer
conceptually (at least to me) and it would give life to the concept of
modules. But others might have objections.

Regarding "more important subjects": I agree that we urgently need a
priorisation of the various topics discussed on the mailing list (some of
the threads have apparently died albeit the issues have not been solved).
A kind of bug tracker would be of great value. Maybe Github could to the
job?

Felix