(CGNS Documentation Home Page)
(Steering Committee Charter)
(Overview and Entry-Level Document)
(A User's Guide to CGNS)
(Standard Interface Data Structures)
(SIDS-to-ADF File Mapping Manual)
(SIDS-to-HDF File Mapping Manual)
(ADF User's Guide)
(CGNS Tools and Utilities)
CGNS Steering Committee
6 November 2001
2:00pm Eastern Time
Telecon Number: (954) 797-1657, participant code: 995403
The meeting was called to order at 2:00pm.
There were 16 attendees, as listed below.
- Charter/Membership - Bob Bush indicated that he received a
letter from ONERA indicating that they would like to be formal members
of the Steering Committee. Marc Poinot attended the meeting and
introduced himself and described ONERA's interest in the committee and
their activities with CGNS. After some discussion, it was decided to
introduce a formal motion at the Reno meeting to increase the number of
Steering Committee members allowed by the Charter to 17, and to elect
ONERA to serve on the Steering Committee.
- ISO Status - Ray Cosner was unavailable for the telecon. Bob
Bush gave a quick summary of the status. There was a thorough review
of the draft documents at the ISO meeting in Japan in September. The
process is continuing more or less on schedule.
- Documentation - Charlie Towne gave the status of the CGNS
documentation pages of the web site. NASA closed all external access
to their web pages following the September 11 incidents. Charlie has
completed the paperwork required to re-open the site, and expects the
documents to be available soon. In the mean time, he has fielded
several requests for copies of the documentation and sent information to
individuals via e-mail.
The documentation has been revised with clarifications to the
There has been no movement on the AIAA Standard. Charlie Towne will
contact Jim French at the AIAA to see what the next steps should be.
We are waiting for AIAA to request the documentation in the form they
Charlie Towne received e-mail requesting to copy portions of the CGNS
documentation to another site as reference material. As all CGNS
information is considered in the public domain, and we encourage
the widest use of the Standard, the Committee has no objections.
However we strongly recommend that they instead provide links to
the CGNS documentation so that the revisions are reflected at the
referencing site, and the CGNS committees and contributors are be
- Reno Meeting - Dave Edwards reported that he has requested
a room for 30-45 people for Monday evening of the Reno AIAA Aerospace
Sciences Conference for the Steering Committee meeting, and a Users
meeting. These will also be announced at the AIAA web site, and in the
conference proceedings. We are tentatively scheduled for 7-8pm for
the Steering Committee, and 8-9 for the User's meeting. Times will be
A technical paper on the status of CGNS implementations in industry
has been accepted. Dave Edwards is collecting input from various
organizations on their status, and will be drafting the paper in
November. He will send the paper out for review in December, and it
will be presented at the Reno meeting. Anyone interested in having
their organizations CGNS implementation status summarized in the paper
is encouraged to submit contributions to Dave.
- Software Support - The sub-committee working on Object
Oriented language access to CGNS files has been quite active. One of
the questions that has come up is the relationship between CGNS and
ADF. Currently, ADF is the only implementation of the SIDS. However,
there are other database standards (e.g. HDF-5) that might provide
more functionality that ADF (e.g. parallel access). The SIDS and
the emerging ISO standard do not specify how the underlying data is
actually stored, and would seem to permit implementations in addition
to ADF. However, this would potentially destroy the data sharing
capabilities, which is the major driver for CGNS implementations. If
multiple implementations of the SIDS is allowed, it was felt that the
mid-level library and other software supported by the committee should
be able to detect and read all of the allowed implementations, without
user intervention. A definition of what constitutes a `CGNS file' is
needed that spells out our position on what constitutes a CGNS file,
and what the committee will support. Chris Rumsey will draft a policy
statement on data base implementations of CGNS. Bob Bush, Manuel
Kessler and Marc Poinot will review the draft, and the full committee
will review the final statement. We hope to adopt a formal position
that will be published on the Web site at the Reno meeting.
There was some discussion of the current C++ implementation being done
by Manuel Kessler and Udo Tremel, and if it represents a data access
mechanism, or includes enough functionality that it should also be
considered a utility that operates on the data.
The chemistry extension is being re-worked somewhat to conform to new
inputs by chemistry experts. It is hoped that the revision will be
complete soon, and implementation completed (by Intelligent Light) by
the end of January.
The link and user defined data extensions are being implemented by
Intelligent Light, and should be available by the end of January.
Diane Poirier has implemented a CVS based version control system for
the libraries. Intelligent Light is using this system to implement the
extensions and serving as an alpha test for remote updates to the code.
- Issues - Doug McCarthy drafted a policy that would allow,
encourage or enforce dues from the Steering Committee to be used to
fund support activities. There was discussion on the feasibility of
enforcing the policy, and other potential funding mechanisms. It
was felt that proposals for specific extensions to the software were
generally easier to justify funding. We will continue to discuss the
issue as we move forward.
The next meeting is scheduled for Reno in January. Bob Bush (or anyone
else who would like to suggest) will determine if there is a need for a
telecon in December to prepare for the meeting.
The meeting was adjourned at about 3:30.
||Pratt & Whitney