[Developers] help

[jtao at cct.lsu.edu]

Quoting Erik Schnetter <schnetter at cct.lsu.edu>:
> On Sep 28, 2006, at 01:33:32, jtao at cct.lsu.edu wrote:
>> As Erik pointed out in his email, each processor will read its own  data and
>> output its own result. I don't think there is anyway to go around    
>> this on the
>> user's level.
> Cactus offers a hyperslabbing API, which transfers chunks of arrays
> between processors.  If the users' guide is too cryptic, then we  could
> use a blackboard to clarify things.

It seems to me that it is optimal to use parellel IO in Hugh's case but
there might be some other considerations. Anyway, some examples showing the
capabilities of hyperslab will be very helpful.

>> Just to get things started, I output the chunk for each processor
>> labeled by result_Procxxx.dat.
>
> Cactus offers several I/O thorns that can output data in standard
> formats, such as ASCII and HDF5.  However, if you need your own
> special format, then writing the data yourself as you did is often  the
> easiest way.

I tried to use Cactus I/O thorns since the results are dumped in
a grid function. I thought it might be easier but Coord_GetDefaultSystem
was required by thorn IO. It is a natural requirement in many problem
domains but it is uncessary in Hugh's case.

Also, driver::global_nx might be better called driver::global_n1 and so
on just like what was suggested in ADMBase(gxx->g11). As the user base of
Cactus expands, another level of abstraction might be necessary to minimize
confusion in the future.

Regards,
Jian
>
> -erik
>
> -- 
> Erik Schnetter <schnetter at cct.lsu.edu>
>
> My email is as private as my paper mail.  I therefore support encrypting
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