[Nexus-developers] NeXus file conversions, NOBUGS

[Mark Koennecke]

   High everyone,

   concerning Rays recent messages:

   - I hacked NCSA's standard h4toh5 utility which comes with the HDF-5 
     distribution to convert HDF-4 NeXus files to HDF-5 NeXus files 
     properly. Not much work really but some tedium about string handling.
     This utility treats links properly. This was not only stated by NCSA  
     but I checked it also by converting a larger data file. Perhaps I
     should create a patchkit for this sometime....

   - Hacking the h5toh4 utility proved to be to much work, as the file
     structure is changed big time by this utility ( it creates a root 
     group from which everything starts).  

   So there is a good path to convert to the new world of HDF-5. Is the 
   backwards path so important that we have to expend a lot of effort?

   - One thing we should urgently sort out at NOBUGS is the XML issue. 
     People start to define XML file structures everywhere: Ray has
     defined one, Steve King has done a similar thing, Emanuel Farhi as
     well, there is the XML-file structure created by using the NCSA HDF-5 
     to XML utility. Perhaps this one could be check for the link handling 
     problem. I think we should agree on a standard NeXus-XML definition 
     as soon as possible. Nobody has yet a large investment in XML
     software, this may not be the case by the time of the next NOBUGS
     meeting.

  -  I believe now that it becomes unavoidable to extend the NeXus-API to 
     deal with XML-files as well. Forward to version 3.0! XML would also
     address many peoples wish to have ASCII data files for easier
     manipulation.    
  


				Regards,

					Mark Koennecke