Hi
well, I guess I am a candidate
replying to Ed's original request, all these decisions are discussed in our
weekly HDF5 1 hour meeting. We'll add that request to a discussion item, and
thank you for your support
Pedro
At 01:01 PM 8/8/2005, you wrote:
>Hi Ed,
> Sounds like a reasonable idea to me. With Bob leaving soon, someone here
>(possibly me :-) needs to take over our dimension scale data model. Any
>takers?
>
> Quincey
>
>> I have been using dimension scales to store dimension data. The
>> dimension scale code puts several attributes on the datasets to store
>> dimensional metadata. This fragment from h5dump illustrates:
>>
>> DATASET "Distance" {
>> DATATYPE H5T_IEEE_F32LE
>> DATASPACE SIMPLE { ( 3 ) / ( 3 ) }
>> DATA {
>> (0): 0, 0, 0
>> }
>> ATTRIBUTE "CLASS" {
>> DATATYPE H5T_STRING {
>> STRSIZE 16;
>> STRPAD H5T_STR_NULLTERM;
>> CSET H5T_CSET_ASCII;
>> CTYPE H5T_C_S1;
>> }
>> DATASPACE SCALAR
>> DATA {
>> (0): "DIMENSION_SCALE"
>> }
>> }
>> ATTRIBUTE "NAME" {
>> DATATYPE H5T_STRING {
>> STRSIZE 9;
>> STRPAD H5T_STR_NULLTERM;
>> CSET H5T_CSET_ASCII;
>> CTYPE H5T_C_S1;
>> }
>> DATASPACE SCALAR
>> DATA {
>> (0): "Distance"
>> }
>> }
>> ATTRIBUTE "REFERENCE_LIST" {
>> DATATYPE H5T_COMPOUND {
>> H5T_REFERENCE "dataset";
>> H5T_STD_I32LE "dimension";
>> }
>> DATASPACE SIMPLE { ( 2 ) / ( 2 ) }
>> DATA {
>> (0): {
>> DATASET 4392 /Adam/Able/Billy_goat_gruff ,
>> 2
>> },
>> (1): {
>> DATASET 9088 /Adam/Cain/Grumpy_the_camel ,
>> 2
>> }
>> }
>> }
>> }
>>
>>
>> This shows a dimension scale with attributes named CLASS, NAME, and
>> REFERENCE_LIST.
>>
>> Might I suggest that the names of the attributes be preceded with an
>> underscore? (For example _NAME instead of NAME.)
>>
>> The reason is that these attribute names will not be available to
>> users. If the user tries to create an attribute named NAME, he will
>> get an error because one already exists. (This is true in both netCDF
>> and HDF5).
>>
>> It's certain that some users somewhere have used attributes called
>> "NAME." That's why an underscore would be a good idea.
>>
>> Thanks!
>>
>> Ed
>> --
>> Ed Hartnett -- ed@xxxxxxxxxxxxxxxx
>>
</Pedro Vicente Nunes>
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