Re: when will HDF5 support Unicode?

On 2003.12.18 10:30 Ed Hartnett wrote:
Howdy HDF5 Guys!

When will Unicode be supported in HDF5?

Thanks!

Ed


What does this entail? I'm assuming this is that same as HDF string types, with all the features. The only difference is the encoding and the width of
charaters.

What about unicode H5T_CHAR class?

I would think the work is:

* an official HDF name for a sub-class of H5T_STRING, whatever is needed to support that * conversion between ASCII and Unicode?
  * tests
  * update dumper and other key tools

Is there anything else?
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Subject: requirements for anonymous dimensions (and question for John)
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From our requirements on anonymous dimensions:

* Dimensions do not always require a name.
By this do we mearly mean that I can accept a dimension with a zero
length name, and that's it?

Otherwise it acts exactly like a regular dimension?

If so, this will be an easy one!

John, was there something else you had in mind for this that I am missing?
Ed

From owner-netcdf-hdf@xxxxxxxxxxxxxxxx 18 2003 Dec -0700 09:51:20
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Subject: question about HDF5 compression
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Howdy HDF5 Programmers!

From the HDF5 user guide:

       3. Compression Properties
       Chunked data storage (see H5Pset_chunk) allows data compression as
defined by the function H5Pset_deflate. herr_t H5Pset_deflate (hid_t plist_id, int level) int H5Pget_deflate (hid_t plist_id)
       These functions set or query the deflate level of dataset creation
       property list plist_id. The H5Pset_deflate() sets the compression
       method to H5Z_DEFLATE and sets the compression level to some integer
       between one and nine (inclusive). One results in the fastest
       compression while nine results in the best compression ratio. The
       default value is six if H5Pset_deflate() isn't called. The
       H5Pget_deflate() returns the compression level for the deflate method,
or negative if the method is not the deflate method.
This seems to imply that we always get (level 6) compression whenever
using a chunked dataset. Surely this isn't true, is it?

Ed