Is a zero-length attribute in netCDF the same as a scalar, or is it more
like an empty array? I can't imagine a use for the latter, but if it's
needed it's needed.
At 12:45 PM 11/10/2003, Ed Hartnett wrote:
The topic of the day is the perhaps mythical zero length attribute.
Why would one want a zero length attribute? I will leave that question
for the philosophers among us.
Does anyone really use zero-length attributes in the netcdf universe?
Probably there is someone out there who does, since there are a large
number of users out there.
Meanwhile, netcdf supports a zero length attribute, but HDF5,
apparently, does not. When I try to create one I get:
HDF5-DIAG: Error detected in HDF5 library version: 1.6.1 thread 0. Back
#000: H5S.c line 1708 in H5Screate_simple(): zero sized dimension for
major(01): Function arguments
minor(05): Bad value
Woops! So that doesn't work. My reading of the manual on H5Acreate
informs me that:
Currently only simple dataspaces are allowed for attribute dataspaces.
So I can't use an extensible attribute.
What do you think, Quincey, is there a way to have a zero length
attribute in HDF5?
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