graphics/opendx and dropping science/hdf

[Ireneusz SZCZESNIAK]

Hi,

I am Ireneusz Szczesniak.  John Cary and I are the authors of dxhdf5.
As far as I know there are only two packages that import HDF5 data
into OpenDX: dxhdf5 and ImportHDF5.  There are a few very good things
about dxhdf5.

1. dxhdf5 is user friendly: building and installing is standard and
   robust (like a GNU package).  dxhdf5 builds and installs with
   Automake, Autoconf and Libtool.  Now the package easily builds and
   installs on Linux, Mac OS X, IRIX, AIX and possibly on others, but
   we have not tried others.

2. It's reliable.  Since the package was relased in summer 2002, we
   have not heard complaints that the module crashes in OpenDX.  Well,
   the only exception was with AIX, but we found out there was a bug
   in OpenDX, and not in dxhdf5.

3. dxhdf5 is cleanly implemented and can be easily extended.  When I
   work on dxhdf5, it's easy for me to change it, even though I
   completely forgot the code.

4. Aside from importing fields, dxhdf5 imports sets of particles and lets
   you choose the particles you want.  See here:
   http://www-beams.colorado.edu/dxhdf5/ImportHDF5Species.html

5. It imports scalar and vector fields.  Plus, dxhdf5 automatically
   finds out what kind of data you are importing: integer, float or
   double.  Some examples of fields may be found here:
   http://www-beams.colorado.edu/dxhdf5/ImportHDF5Field.html

We presented dxhdf5 at the 18th International Conference on Numerical
Simulation of Plasmas (ICNSP '03), http://web.mit.edu/ned/ICNSP/, and
people there were quite interested in dxhdf5.  Some of them,
unfamiliar with dxhdf5, were saving their data in plain text files
even tough they knew about HDF5, because can import text data into
OpenDX and other software.  Back then we got some feedback on what
people really need and we got some good ideas for further development.

If you have some questions, please let us know.


Best,
Ireneusz Szczesniak

********************************************
* Ireneusz SZCZESNIAK - research assistant *
* Tel: +48 (32) 231-73-19, extension 204   *
* http://www.iitis.gliwice.pl/~iszczesniak *
********************************************

On Thu, 8 Apr 2004, Mike Folk wrote:

> Date: Thu, 08 Apr 2004 11:06:53 -0500
> From: Mike Folk <mfolk at ncsa.uiuc.edu>
> To: Quincey Koziol <koziol at ncsa.uiuc.edu>,
>      Mikhail Teterin <mi+kde at aldan.algebra.com>
> Cc: ports at FreeBSD.org, hdfnews at ncsa.uiuc.edu, ijliao at FreeBSD.org,
>      yuri at irfu.se, corecode at corecode.ath.cx, tilman at arved.de,
>      flynn at energyhq.homeip.net, aa8vb at nc.rr.com,
>      toyonaga at msd.ts.fujitsu.co.jp, tg at FreeBSD.org, kay_lehmann at web.de
> Subject: Re: graphics/opendx  and dropping science/hdf
>
> I completely forgot:  Ireneusz Szczesniak has done an open dx
> implementation called "dxhdf5", and has some nice documentation and other
> materials at http://www-beams.colorado.edu/dxhdf5/.   We need to be working
> with her.
>
> Mike
>
> ------------------------------------
> (Thanks for cc'ing me Quincey.)
> Just a couple other comments about open dx:
>
> The CACTUS project has been using open dx with hdf5 for several years.  I
> strongly suspect there are others, but don't know specifics.  As far as I
> know, the CACTUS folks haven't documented their work (I asked them a few
> times, but that was a couple of years ago), so I don't know exactly how
> they organize the data.
>
> Open dx and hdf5 are a natural combination, and it's a pity we haven't
> married them in some formal way, and we'd love to work with you if you move
> in that direction.
>
> Mike
>
> At 09:27 AM 4/8/2004, Quincey Koziol wrote:
> >Hi Mikhail,
> >
> > > I intend to drop the science/hdf port. It was obsoleted by hdf5 long ago
> > > (was it?), it breaks on some some 64bit platforms, it conflicts with
> > > math/netcdf.
> > >
> > > All the technical issues are, probably, fixable, but the obsoleteness
> > > makes them not worth the effort. Or so it seems.
> > >
> > > The only port relying on science/hdf is graphics/opendx and only if
> > > WITH_HDF is defined. Unfortunately, opendx does not (yet?) support hdf5.
> > >
> > > So...
> > >       . Does hdf5 really obsolete hdf4?
> >     No, they are different file formats & libraries, etc.
> >
> > >       . Does hdf support add much value to opendx at all,
> > >         or can we just remove it?
> >     I don't know.
> >
> > >       . If not, should I (or some other helping hand) try to patch
> > >         opendx to use hdf5?
> >     It would certainly be nice if opendx supported hdf5.
> >
> > >               or
> > >       . bring the old hdf4 into the 21st century (fixing the types,
> > >         depending on math/netcdf instead of building its own)?
> >     It shouldn't be _too_ hard to fix the type information in hdf4 (I can
> > help
> >you with that, if you'd like), but it would be _very_ hard to depend on
> >math/netcdf instead of its own.
> >
> >     Quincey
> >
> > >
> > > Thanks for any ideas,
> > >
> > >       -mi
> > >
>
> --
> Mike Folk, Scientific Data Tech (HDF)   http://hdf.ncsa.uiuc.edu
> NCSA/U of Illinois at Urbana-Champaign          217-244-0647 voice
> 605 E. Springfield Ave., Champaign IL 61820     217-244-1987 fax
>