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[netCDF #XYO-599400]: A possble netCDF-4 bug?

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  • Subject: [netCDF #XYO-599400]: A possble netCDF-4 bug?
  • Date: Thu, 05 Nov 2009 21:30:06 -0700
Lynton,

Evidently the HDF5 limit that's being exceeded is H5O_MESG_MAX_SIZE, defined as
65536   /*max obj header message size  */
in H5Oprivate.h.  You're right, this seems to have something to do with 
initializing
a header object with HDF5 fill values.  Your compound type has a double array 
member
with 8192 values, and sizeof(double)*8192 is 65536, so I think that's the 
problem.
I expect if you used float instead of double, you could have twice as many of 
them.

I'm not sure why the HDF5 size limit for an array type is only 2**16, except 
that the 
documentation says 

  A compound datatype is similar to a struct in C or a common block in Fortran. 
  It is a collection of one or more atomic types or small arrays of such types.
    ...
  Each member can be a small array of up to four dimensions.
  http://www.hdfgroup.org/HDF5/doc/H5.intro.html#Intro-PMCreateCompound

--Russ


Russ Rew                                         UCAR Unidata Program
address@hidden                     http://www.unidata.ucar.edu



Ticket Details
===================
Ticket ID: XYO-599400
Department: Support netCDF
Priority: Normal
Status: Closed