Subject: HDF Newsletter #20

From: [email-masked] (Barbara Jones )
Date: 4 Apr 1996 18:58:32 GMT

HDF Newsletter #20

                       April 2, 1996

HDF4.0r1 patch 01 is on the NCSA ftp server. Changes include:

   1. Port to the PowerPC/68k Macintosh using the MetroWerks 
      CodeWarrior(8) C compiler. The Fortran interface is not
      available yet.  In addition, the netCDF interface works 
      but currently you are unable to read old netCDF (XDR) 
      files.  You need at least CW8 to use this version of the 
      library as previous versions had problems with the ANSI-C 
      memory allocation routines. Precompiled code and source 
      code can be found on the NCSA ftp server in:

        /HDF/HDF4.0r1/hqx/.

      As there was no HDF 4.0r1 release for the Macintosh, please 
      refer to the /HDF/HDF_Current/release_notes/ABOUT_4.0r1 file 
      as well as the /HDF/newsletters/Newsletter19.txt file on the
      NCSA ftp server, for information on what has changed in this 
      release.

   2. Port to Windows NT/95 using Visual C++ 4.0. The Fortran 
      interface is not available yet.  Precompiled code and 
      source code can be found on the NCSA ftp server in:

        /HDF/HDF4.0r1/zip/.

      As there was no HDF 4.0r1 release for Windows NT/95, please 
      refer to the /HDF/HDF_Current/release_notes/ABOUT_4.0r1 file 
      as well as the /HDF/newsletters/Newsletter19.txt file on the
      NCSA ftp server for information on what has changed in this 
      release.

   3. A bug has been fixed on the SDS interface. Now the record 
      number will be updated for UNLIMITED dimensions when 
      ncsync (ncsnc) is called to write data to hdf files. 

   4. A bug has been fixed in the UNLIMITED dimension record to 
      improve backward compatibility. 

   5. An option to generate binary output has been added to 
      dumprig and dumpsds in hdp, the HDF dumper. It is in beta 
      test stage. 

   6. Parameter 'class' in vffndcls() has been changed to 'vgclass' 
      to avoid conflicts with the C++ reserved word 'class'. 

   7. All definitions for the names and classes of vdatas and 
      vgroups that are created by the GR or SD interfaces and 
      are used in hdf files have been moved to hdf/src/hlimits.h. 
      These names and classes are reserved by HDF.
      Users' applications should not name their vdatas/vgroups 
      using these reserved words. Pre-defined attribute names
      are included in hlimits.h as well. 
      A list of these reserved names (and classes) is attached 
      at the end of this newsletter.
 
   8. Other bug fixes.

   Patch files are located in 

      /HDF/HDF4.0r1/patches/
   
   For HDF 4.0r1 patch 01, the entire source distribution, including 
   the patch, is located in:

      /HDF/HDF4.0r1/patches/patchedsrc/

   The READMEs in these directories explain how to apply the patch.

   HDF4.0r1 patch 01 has been tested on the Macintosh PowerPC and 68K,
   HPUX, IRIX5.3, IRIX6.1_64, IRIX6.1_32, SunOS4.1.4, Solaris 2.5, 
   and Dec Alpha OpenVMS.  Precompiled executables for these UNIX
   (except IRIX6.1_32) and OpenVMS platforms in /HDF/HDF4.0r1/bin/ 
   on the NCSA ftp server, have been updated to HDF4.0r1 patch 01. Due 
   to limited resources we do not plan to update the executables for 
   other platforms. If any user has problems compiling patch 01 on 
   other platforms please contact [email-masked]. We will try 
   our best to work with you.

Known problems:

1. Hdp needs to be upgraded to dump objects created by the GR 
   and AN interfaces. 
2. Fortran routines (for example vsfwrit) that have a parameter 
   that may be a character type or numeric type, do not work 
   correctly on some systems, such as VMS and T3D. This problem 
   will be corrected in the next release.
3. Some users indicated that the current limits on the number 
   of accessible files/objects and size of vdata fields 
   restricted their applications. These limits will be extended
   in future releases and versions.  

------------- reserved names and classes ------------------------
By GR interface   

Vdata/vgroup names and classes:

"RIG0.0" -- name of the Vgroup containing all the images in GR
"RI0.0" -- name of a Vgroup containing information about one image 
           in GR 
"RIATTR0.0N"  -- name of a Vdata containing an attribute in GR 
"RIATTR0.0C" -- class of a Vdata containing an attribute  

Atrribute names:

"FillValue" -- name of an attribute containing the fill value

By SD interface

Vdata/vgroup names and classes:

"Attr0.0" -- class of a Vdata containing SD interface attribute
"Var0.0" -- class of a Vgroup representing an SD NDG 
"Dim0.0" -- class of a Vgroup representing an SD dimension 
"UDim0.0" -- class of a Vgroup representing an SD UNLIMITED dimension 
"DimVal0.0" -- class of a Vdata containing an SD dimension size 
              and fake values 
"DimVal0.1" -- class of a Vdata containing an SD dimension size  
"CDF0.0" -- class of a Vgroup representing all SD SDSs in a file
"Data0.0" -- defined but not used yet 
"VALUES" -- field name of a vdata which contains values of an 
            SD attribute 

Atrribute names:

"_FillValue"  -- user defined fill value
"long_name" -- data/dimension label string
"units"     -- data/dimension unit string
"format"    -- data/dimension format string
"coordsys"  -- data coordsys string
"valid_range" -- valid range of data values
"scale_factor" -- data calibration factor
"scale_factor_err" -- data calibration factor error
"add_offset" -- calibration offset
"add_offset_err" --  calibration offset error
"calibrated_nt"  -- data type of uncalibrated data