Support for NPP/NPOESS by The HDF Group Mike Folk, Elena Pourmal The HDF Group Annual HDF Briefing to ESDIS March 31, 2009 March Annual HDF Briefing to ESDIS1

Goal March Annual HDF Briefing to ESDIS2 To develop and adapt HDF5 software and provide HDF5 support for NPP/NPOESS.

NPOESS Priorities and HDF5 Data calibration/validation Data accessibility and usability Tool development System maintenance User support March Annual HDF Briefing to ESDIS

Areas of immediate need 1.Ensure easy and intuitive access and use by diverse communities 2.Enable producers and consumers to view content, manage metadata, and convert data to other formats. 3.Provide high-quality, rapid-response support of HDF5 for NPOESS users at all levels. March Annual HDF Briefing to ESDIS

1. Ensure easy and intuitive data access and use by diverse communities March Annual HDF Briefing to ESDIS5

Region references March Annual HDF Briefing to ESDIS6 Root -/ Data Array Product GroupAgg Gran N Reference Object Reference Region Reference Region

New routines to facilitate data access Access data pointed to by region references  Retrieving data pointed to by region references requires a series of complex function calls.  New API would encapsulate these into a few routines. Rewrite region references in datasets  When a dataset with region references is moved from one file to another, the references of the datasets are invalid in the new file.  The process of updating reference values is complex and error prone.  New functions can address both of these concerns. March Annual HDF Briefing to ESDIS

Access individual quality flags.  NPOESS quality flags are packed into an integer.  In HDF5, integer types are “atomic” – any I/O operation access an entire integer.  To access individual NPOESS quality flags in a convenient and consistent manner, routines are needed that can unpack and return individual quality flags represented by bits packed in an HDF5 integer. March Annual HDF Briefing to ESDIS

2. Enable producers and consumers to view content, manage metadata, and convert data to other formats. March Annual HDF Briefing to ESDIS9

Tools enhancements There is interest in tools to view and export packed quality flag values, as well as data pointed to by region references. Tools of particular interest:  h5dump – a command line utility for dumping information from an HDF5 file.  HDFView – a graphical tool for displaying and editing the contents of HDF5 files. March Annual HDF Briefing to ESDIS

Tool enhancements H5dump modifications  Extract, display, and export a subset of packed bits corresponding to NPOESS quality flags.  Extract, display, and export data pointed to by region references. HDFView modifications  Display a rectangular region of data in a dataset corresponding to set of region references.  Display packed bits corresponding to the NPOESS quality flags. March Annual HDF Briefing to ESDIS

3. Provide high-quality, rapid- response support of HDF5 for NPOESS users at all levels. March Annual HDF Briefing to ESDIS12

Support enhancements Assign high priority to helpdesk requests from the NPOESS user community, and ensure a one business-day response to all queries known to be NPOESS-related. Support HDF5 on AIX 5.2. March Annual HDF Briefing to ESDIS

Status Region reference  API Initial design defined, implemented Requirements/design draft doc, RFC  Tools H5dump, HDFView: gathering requirements Quality flags  API: requirements/design draft doc, RFC  Tools: just starting to think about March Annual HDF Briefing to ESDIS

Status HDF5 support  Small but steady stream of requests to helpdesk from NPP/NPOESS community  Request range from simple questions to requests for new features AIX 5.2  AIX 5.3 tested daily on borrowed system  Hoping to get access on IDPS system at NASA March Annual HDF Briefing to ESDIS

Future plans Complete current tasks by August 31, Working on long-term agreement to continue the same three-pronged approach 1.Technology development to improve usability for users of NPOESS/NPP data products 2.High quality, rapid response support to NPOESS/NPP HDF5 users at all levels 3.System maintenance and support March Annual HDF Briefing to ESDIS

Thank You! This report is based upon work to be supported by a Cooperative Agreement with NASA under NASA contract NNG08HZ14C. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Aeronautics and Space Administration. March Annual HDF Briefing to ESDIS17

Questions/comments? March Annual HDF Briefing to ESDIS18