F90 API

[Ray Osborn]

I've finally got around to releasing an alpha version of the F90 NeXus API.
I have only managed to test it on VMS using the Digital Fortran 90 compiler,
so I can make no claims for portability yet.  However, I don't believe that
I have used any non-standard Fortran 90 code, so it should work.  Please try
it out and let me know.

As well as porting the core API that Mark and Przemek developed, I have
added a set of utility routines, that perform a number of functions that I
have found useful.  In particular, there are routines that search for data
with either signal or axis attributes, and routines for enabling the linking
of different groups.  The core API provides a method of linking data sets to
more than one group, but there is no method of locating the other group to
which the data is linked.  This can be important if you are storing the
plottable data in an NXdata group, but need obscure detector information
(e.g. helium tube gas pressure) stored in a separate NXdetector group.  This
method of linking plottable data to the relevant instrument details was an
important part of the NeXus design, but it has never been fully implemented,
and even now, I have some doubts about how robust my method really is.
Please let me know if you have any thoughts on what I've done.

Since it didn't exist before, I've implemented a very simple terminal
browser using the F90 interface.  It's called NXbrowse.f90 - when compiled
and linked, it provides a command line interface to any NeXus file.  When
you run it, type HELP from the prompt to see what the commands are.  There
are other example files now on the FTP server.  If you have any example code
that you wouldn't mind being posted on the web, I'd be happy to include it.

Please check <http://www.neutron.anl.gov/NeXus/NeXus_news.html> for further
details.

Regards,
Ray Osborn
--
Dr Ray Osborn                Tel: +1 (630) 252-9011
Materials Science Division   Fax: +1 (630) 252-7777
Argonne National Laboratory  E-mail: ROsborn at anl.gov
Argonne, IL 60439-4845