Re: 1.8 file format

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Meanwhile yet another question on a different topic:

Im trying to figure out what the NPOESS data files are doing with "Reference 
Types".

Case 1 is a Reference with type = 0 (Object Reference)

long VIIRS-AF-EDR_Aggr(5);
   :AggregateBeginningDate = "2003125";
   :AggregateBeginningGranuleID = "NPP001212126088";
   :AggregateBeginningOrbitNumber = 9; // int
   :AggregateBeginningTime = "10109.840960z";
   :AggregateCreationDate = "2003125";
   :AggregateEndingDate = "2003125";
   :AggregateEndingGranuleID = "NPP001212126088";
   :AggregateEndingOrbitNumber = 9; // int
   :AggregateEndingTime = "101038.325248z";
   :_LastModified = "2005-08-29T15:54:58Z";

data:

{2928, 3528, 3800, 4072, 4344}

The 5 values are indeed object references to 5 other datasets in the file. Any 
clues on how this is used, or is it an internal structure that should be left 
alone?

h5dump is:

DATASET "VIIRS-AF-EDR_Aggr" {
           DATATYPE  H5T_REFERENCE
           DATASPACE  SIMPLE { ( 5 ) / ( 5 ) }
           ATTRIBUTE "AggregateBeginningDate" {
              DATATYPE  H5T_STRING {
                    STRSIZE 7;
                    STRPAD H5T_STR_NULLTERM;
                    CSET H5T_CSET_ASCII;
                    CTYPE H5T_C_S1;
                 }
              DATASPACE  SIMPLE { ( 1, 1 ) / ( 1, 1 ) }
           }
           ATTRIBUTE "AggregateBeginningGranuleID" {
              DATATYPE  H5T_STRING {
                    STRSIZE 15;
                    STRPAD H5T_STR_NULLTERM;
                    CSET H5T_CSET_ASCII;
                    CTYPE H5T_C_S1;
                 }
              DATASPACE  SIMPLE { ( 1, 1 ) / ( 1, 1 ) }
           }
           ....



Case 2 is a Reference, with type = 1 (Dataset Region Reference).

long VIIRS-AF-EDR_Gran_0(5);

data:

 {3299824, 14172636162555905, 8589934592, 3299824, 14172636162555907}

h5dump is

DATASET "VIIRS-AF-EDR_Gran_0" {
           DATATYPE  H5T_REFERENCE
           DATASPACE  SIMPLE { ( 5 ) / ( 5 ) }

The docs on this are pretty sketchy, i wonder if i could get an expanded 
description of what the Dataset Region Reference structure looks like? Heres 
whats there (last page of 1.6.5 doc):

"Dataset region references are stored as a heap-ID which points to the following 
information within the file-heap: an offset of the object pointed to, number-type 
information (same format as header message), dimensionality information (same format as 
header message), sub-set start and end information (i.e. a coordinate location for each), 
and field start and end names (i.e. a [pointer to the] string indicating the first field 
included and a [pointer to the] string name for the last field)."

specifically:
 "an offset of the object pointed to" = object id ?
 "number-type information (same format as header message)" datatype message?
 "dimensionality information (same format as header message)" = dataspace 
message?

and then im even more lost as to what the fields are....


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