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CGNS Documentation

25 Oct 2017
12 Sep 2017
25 Jul 2017
05 May 2017
01 Feb 2017
29 Nov 2016
23 Sep 2016
06 Jul 2016
20 May 2016
  • Fixed typo in Section 10.3 (GasModelType_t changed to ModelType_t). Also created more complete index to the SIDS, including section and subsection numbering.
09 Apr 2016
04 Mar 2016
10 Dec 2015
21 Oct 2015
25 Sep 2015
  • Updated SIDS documentation to V3.3, including changes associated with CPEX 0039.
23 Sep 2015
  • Updated documentation to V3.3. This was mostly simply a change to the posted numbering conventions, other than the addition of the new quartic elements from CPEX 0038 to the MLL in Typedefs.
09 Sep 2015
22 May 2015
05 Mar 2015
02 Dec 2014
07 Oct 2014
04 Sep 2014
02 Sep 2014
  • Added quartic element definitions (CPEX 0038) to Line Elements, Surface Elements, and Volume Elements to the SIDS definitions only. Not coded into the MLL yet (when it is, the CGNS Version designation will be changed to 3.3). Also fixed some typos, grammar, and did some minor formatting fixes.
24 Feb 2014
07 Feb 2014
  • Official release of version 3.2.1. The 3.2 (beta) documentation has been switched to be primary documentation.
04 Feb 2014
18 Dec 2013
19 Sep 2013
26 Jul 2013
  • Minor change in SIDS docs: differences from previous versions put in reverse chronological order.
16 Jul 2013
8 July 2013
14 May 2013
30 Apr 2013
29 Mar 2013
  • Added description of CG_CONFIG_FILE_TYPE that was missing; also added more description of cg_set_file_type on MLL File Operations page.
14 Mar 2013
  • Made minor mods in overview and intro of PDF version of SIDS v3.2, to remove stale discussion, add abstract, and add some clarity.
13 Mar 2013
27 Feb 2013
  • Minor correction from *ptset_type to ptset_type in argument of cg_ptset_write in Point Sets of MLL documentation.
26 Feb 2013
  • Added AdditionalFamilyName_t node documentation to structures.html, sids and filemap.
23 Feb 2013
  • Updated the CGNStools documentation.
  • Added external link image to places it was missing.
  • New Parallel CGNS capability.
15 Feb 2013
  • Introduced Version 3.2 (beta).
  • Added AdditionalFamilyName_t under BC_t, Zone_t, and ZoneSubRegion_t, and added FamilyName_t under Family_t (a hierarchy of families is now possible); according to CPEX 0033 and 0034.
  • Added new cubic elements in Conventions, according to CPEX 0036.
15 Feb 2013
  • Changes associated with update to 3.1.4.
  • Updated MLL to version 3.1.15: One set of changes is in BC and include new description under location, as well as under "Notes: (see CPEX 0031)". Another change is in File Operations to the default for CG_CONFIG_COMPRESS.
  • Added new function, cg_precision, to read precision (32 or 64 bit) in the MLL File Operations.
  • Updated SIDS to version 3.1.8: Changes are in BC and include modified table describing usage of GridLocation vis CellDimension under BC_t.
  • Updated CGNSTools to version 3.1.2: Added new Tools description under CGNSTools.
11 Dec 2012
25 Oct 2012
28 Sep 2012
29 Aug 2012
31 Jul 2012
  • Added reminder that max number for DataDimension is 12 for Data Arrays.
01 May 2012
16 Mar 2012
3 Feb 2012
  • Changes associated with new MLL doc number 3.1.12: Added section "Interfacing with CGIO" under "File Operations"; also updated Midlevel Sitemap to add "Interfacing with CGIO". Also corrected type for "pnts" under cg_sol_ptset_write, cg_subreg_ptset_write, and cg_discrete_ptset_write (should be const cgsize_t *, and not cgsize_t *).
24 Jan 2012
17 Jan 2012
  • Changed NormalListFlag to NormalListSize in MLL's cg_boco_info and updated MLL doc number from 3.1.10 to 3.1.11. Added LongInteger as possible type for DataType in Data Arrays and for datatype in Flow Solution Data.
05 Jan 2012
04 Jan 2012
03 Jan 2012
20 Dec 2011
  • In File Mapping, added info about cgsize_t for 64-bit integers. In some places in text, I4 replaced by cgsize_t. Added "bit" to DataType description for DataArray_t. Many updated figures to reflect 64-bit integer changes (I4 changed to cgsize_t).
09 Dec 2011
  • Added statement under all Input/Output listings in the MLL noting that for Fortran calls, all integer arguments are integer*4 in 32-bit mode and integer*8 in 64-bit mode, along with a link to: 64-bit Fortran Portability and Issues.
08 Dec 2011
21 Nov 2011
24 Oct 2011
31 Aug 2011
11 Aug 2011
  • Added minor clarification in Element Connectivity in the Mid Level documentation, regarding global numbering system to insure that every element within a zone has a unique number.
06 Jul 2011
07 Jun 2011
06 Jun 2011
28 Apr 2011
  • In SIDS, added ZoneSubRegion_t node under Zone_t (mistakenly left out) in Zone_t. Also minor descriptor change regarding file mapping in intro.
26 Apr 2011
  • Minor changes to Charter, Overview document, and User's Guide to refer to CGIO rather than ADF, to refer to 3.1 as the latest version, and to update some stale references.
25 Apr 2011
  • Reorganized File Mapping documentation to separate context from content. SIDS-to-ADF File Mapping Manual changed to SIDS File Mapping Manual, which contains context. The content is now in ADF Implementation, HDF5 Implementation and Python Implementation.
  • SIDS, SIDS File Mapping and MLL documentation all updated to include CPEX 0027 (Time-dependent Connectivities), CPEX 0030 (Regions) and CPEX 0031 (General SIDS Improvements).
  • Added CGIO User's Guide which documents the low-level interface replacement for the ADF Core routines. The CGIO calls work for both ADF and HDF5.
23 Mar 2011
04 Mar 2011
03 Mar 2011
02 Mar 2011
  • Posted draft minutes from the March 2, 2011 Steering Committee telecon. (PDF).
  • Posted new SIDS-to-Python file mapping manual (PDF only).
  • Updated version numbering for User's Guide, SIDS-to-ADF, and SIDS-to-HDF documents (no other changes to the documents), to reflect the release of CGNS Version 3.1.
01 Mar 2011
  • In Mid-Level Library, added information in File Operations about file_type = CG_FILE_ADF2, which can be used to write a Version 2.5 file from Version 3 when compiled in 32-bit.
25 Feb 2011
  • Made Version 3.1 the current official document release, moved 2.5 to "prior version" status.
25 Feb 2011
23 Feb 2011
  • Modified Mid-Level Library:
    • Added particular changes of "int" to "cgsize_t" throughout.
    • Added new sections on 64-bit C and Fortran Portability and Issues.
    • Added references to xxxxNull and xxxxUserDefined under Typedefs.
    • New Document Version is 3.1.3, corresponding to CGNS Version 3.1.
  • Modified SIDS Document:
    • Changed description of BCType_t slightly, to clarify the simple and compound types.
    • Added section Model Type Structure Definition.
    • Corrected ModelTypeNull and ModelTypeUserDefined listings (where enumerated values are a subset of the ModelType_t enumeration).
    • New Document Version is 3.1.2, corresponding to CGNS Version 3.1.
04 Feb 2011
  • Modified Mid-Level Library:
    • Changed Null to CG_Null and UserDefined to CG_UserDefined, and added comment under General Remarks about their usage.
    • New Document Version is 3.1.2, corresponding to CGNS Version 3.1.
  • Modified SIDS Document:
    • Changed Null to xxxxNull and UserDefined to xxxxUserDefined, as appropriate.
    • Also made sure that the xxxxNull is listed first, and the xxxxUserDefined is listed second.
    • New Document Version is 3.1.1, corresponding to CGNS Version 3.1.
01 Feb 2011
  • Modified doc home page to change mention of ADFviewer to CGNSview.
  • Modified User's Guide
    • Changed references of ADFviewer to CGNSview.
    • Updated code snippet examples to reflect changes in new UserGuideCodeV3.1, including changes of MODE_READ to CG_MODE_READ (for example) in cg_open calls.
    • Added mention of cg_error_handler.
    • Changes to user/index.html, faq.html, intro.html, additional.html, started.html, trouble.html.
    • New Document Version of Guide is 1.1.13, corresponding to CGNS Version 3.1.
  • Modified Mid-Level Library
    • Added new table of Typedef Name Access Functions under General Remarks.
    • Added description of cg_elements_partial_write.
    • Added descriptions of cg_save_as, cg_set_file_type, cg_get_file_type, cg_error_handler, cg_set_compress, cg_get_compress, cg_set_path, and cg_add_path.
    • New Document Version is 3.1.1, corresponding to CGNS Version 3.1.
  • On Sitemap for CGNS Tools and Utilities, updated old ADFviewer to new CGNSview, along with relevant new information.
  • Major update of CGNS tools and utilities, including switch from use of ADFviewer to CGNSview; New Document Version is 2.0.
11 Jan 2011
  • Caught up with postings of telecon minutes. Added CGNS Tutorial slides from Orlando Jan 2010. Added 2008-2009 CGNSTalk archives.
26 May 2009
  • In the Applications Software section of the CGNS Overview and Entry-Level Document, changed the contact person for notification about new CGNS applications.
  • In the SIDS document, deleted the contact info for questions about the SIDS, since it was no longer valid, and is now covered by the CGNStalk mailing list.
22 May 2009
  • Posted draft minutes from the May 20 CGNS Steering Committee telecon. (HTML, PDF).
21 May 2009
  • In the Accessing a Node description in the "Navigating a CGNS File" section of the Mid-Level Library document, corrected an error in the syntax for the cg_gopath_f Fortran routine. The last two arguments were reversed. Thanks to Richard McDonald at the USGS for the correction.
20 May 2009
  • In the Steering Committee Charter, deleted the list of current member organizations in the Organization/Bylaws section. This is now available at the CGNS web site.
12 May 2009
  • In the Zone Information description in the "Structural Nodes" section of the Mid-Level Library document, added a sentence emphasizing that zones must be named alphanumerically to ensure proper retrieval.
6 Apr 2009
  • Posted draft minutes from the Apr 1 CGNS Steering Committee telecon. (HTML, PDF).
14 Jan 2009
9 Jan 2009
  • Posted draft minutes from the Jan 7 CGNS Steering Committee meeting. (HTML, PDF).
19 Nov 2008
  • Posted draft minutes from the Nov 5 CGNS Steering Committee telecon. (HTML, PDF).
9 Oct 2008
  • Added AIAA Paper 2008-0479, titled "Benchmarking the CGNS I/O Performance," by Thomas Hauser, presented at the 46th AIAA Aerospace Sciences Meeting and Exhibit. [HTML, PDF (318K, 8 pages)]
23 Sep 2008
  • Posted draft minutes from the Sep 10 CGNS Steering Committee telecon. (HTML, PDF).
11 Sep 2008
  • Modified the description of the Elements_t structure in the SIDS to modify how NGON_n and NFACE_n are used to define general polyhedral elements. Each face of an element (except for boundary faces) must be shared by another element; faces may not be duplicated in NGON_n with opposite orientations. The sign of the face number for a particular polyhedral element in NFACE_n determines the direction of its normal with respect to that element - positive for outward, negative for inward. Also modified the NGON_n/NFACE_n example for consistency with the above change.
17 July 2008
  • Modified each page to use server-side includes for adding the footer.
11 July 2008
  • Posted draft minutes from the July 2 CGNS Steering Committee telecon. (HTML, PDF).
19 June 2008
  • Modified the description of the Elements_t structure in the SIDS to incorporate the new definition of the NGON_n element type, and add the NFACE_n element type. Also added examples illustrating their use.
17 June 2008
  • In the Typedefs section of the Mid-Level Library documentation, added PYRA_13 and NFACE_n to the list of supported key words for ElementType_t.
27 May 2008
  • Posted draft minutes from the May 7 CGNS Steering Committee telecon. (HTML, PDF).
14 May 2008
  • In the SIDS document, added a PYRA_13 element to the description of the unstructured grid element numbering conventions for pyramid elements.
  • Made a minor change in the Getting Started section of the User's Guide to CGNS, involving the use of PointList or PointRange with GridLocation set to FaceCenter.
12 Mar 2008
7 Mar 2008
8 Feb 2008
  • Added HTML versions of all the PDF attachments to meeting and telecon minutes.
29 Jan 2008
23 Jan 2008
18 Jan 2008
  • Posted draft minutes from the Jan 6 CGNS Steering Committee meeting. (HTML, PDF).
5 Dec 2007
  • Added an "external link" symbol (external link symbol) to all links to non-NASA sites, per NASA policy.
29 Nov 2007
  • Posted draft minutes from the Nov 28 CGNS Steering Committee telecon. (HTML, PDF).
7 Nov 2007
  • Modified the description of the TurbulenceModel_t structure to add references to the specific models that correspond to the TurbulenceModelType names, and to add a recommendation for handling subsequent changes to the models.
  • In the User's Guide to CGNS, added a note that it was originally published as NASA/TM-2001-211236, October 2001.
9 Oct 2007
  • Modified the list of current member organizations in the CGNS Steering Committee Charter to reflect the name change of Thaerocomp Technical Corporation to TTC Technologies.
19 Sep 2007
  • Posted minutes from the Sept 12 CGNS Steering Committee telecon. (HTML, PDF).
14 Sep 2007
11 July 2007
5 July 2007
  • In the SIDS document, rearranged discussion of the AIAA Recommended Practice version of the SIDS, noting that it's out of date, and removed links to it on the CGNS documentation home page.
19 June 2007
  • Posted minutes from the May 22 CGNS Steering Committee telecon. (HTML, PDF).
26 Mar 2007
  • Posted minutes from the Mar 21 CGNS Steering Committee telecon. (HTML, PDF).
30 Jan 2007
  • Corrected a minor error in Mid-Level Library document, changing the error status names ALL_OK, ERROR, NODE_NOT_FOUND, and INCORRECT_PATH to CG_OK, CG_ERROR, CG_NODE_NOT_FOUND, and CG_INCORRECT_PATH, respectively.
17 Jan 2007
  • Corrected an error in SIDS document, in the description of the unstructured grid element numbering conventions for pyramid elements. For the PYRA_14 element, node 14 should be at the center of the quadrilateral face, not the center of the element.
  • Several modifications to the Mid-Level Library manual, for consistency with the current CGNS Version 2.5 beta.
    • New functions to check file validity and configure some internal CGNS library options.
    • Additional functions providing alternate ways to access a node.
    • Changes in the use of functions for partial writes of coordinate, element, and solution data. The result is now always the union of the existing and new data. As part of this, the functions cg_section_read_ext and cg_elements_read_ext are no longer needed and have been removed, and new functions cg_ElementPartialSize and cg_elements_partial_read have been added.
  • Corrected typo in the data type of the argument data in the Mid-Level Library function cg_free.
30 Nov 2006
  • Corrected error in the table at the top of the Export Utilities section. cgns_to_tecplot converts from CGNS to Tecplot, not the other way round.
16 Oct 2006
  • Corrected an error in the Mid-Level Library manual, in the argument list for cg_conn_write_short. Even though the specific cell connectivity data aren't needed, the name of the donor zone is still required. Thanks to Thorsten Schwarz for spotting the problem.
11 Oct 2006
25 Sep 2006
  • Updated some links and contact points listed in the Applications Software section of the CGNS Overview and Entry-Level Document.
5 Sep 2006
  • In the CGNS Steering Committee Charter,
  • In the Mid-Level Library, modified the description of the size argument for the Zone Information routines, attempting to clarify the definition for unstructured grids.
  • In the SIDS,
    • Modified the description of VertexSize for the Zone_t structure to clarify its definition for unstructured grids.
    • Modified the description of the GridConnectivity_t structure to allow GridLocation to be either Vertex or FaceCenter for Abutting and Abutting1to1 interfaces.
8 Aug 2006
  • Posted minutes from the Aug 2 CGNS Steering Committee telecon. (HTML, PDF).
28 July 2006
14 June 2006
  • Added slides from the special "CGNS Tutorial Session" at the 36th AIAA Fluid Dynamics Conference in San Francisco, California, June 5-8, 2006.
17 May 2006
  • Posted minutes from the May 10 CGNS Steering Committee telecon. (HTML, PDF).
13 Apr 2006
10 Apr 2006
  • Updated some links and contact points listed in the Applications Software section of the CGNS Overview and Entry-Level Document.
27 Mar 2006
1 Mar 2006
3 Feb 2006
  • In the Mid-Level Library Manual, corrected a typo in the name of the Fortran routine cg_array_read_as_f, used to read data arrays (the "_f" was left off).
17 Jan 2006
  • Updated (and alphabetized) the list of current member organizations in the CGNS Steering Committee Charter.
  • Posted minutes from the Jan 11 CGNS Steering Committee meeting. (HTML, PDF).
10 Jan 2006
  • Corrected a typo in the PDF version of the SIDS document involving an escaped underscore. Thanks to Marc Poinot for spotting it.
21 Dec 2005
15 Dec 2005
  • In the SIDS document,
    • Added a paragraph at the start of the Introduction intended to better explain the importance and benefits of using CGNS.
    • Added a bit to the description of the RotatingCoordinates_t data structure to more clearly explain its use, and deleted the sentence saying that it doesn't cover cases where the zone interfaces are not perpendicular to the axis of rotation.
    • Made a few other changes in various places to correct typos and add clarification.
    Thanks to Kurt Weber for his review of the updated AIAA Recommended Practice, and for suggesting these changes.
7 Dec 2005
21 Nov 2005
  • Eliminated most usage of images for equation elements throughout the HTML version of the CGNS documentation, in favor of the appropriate HTML character entities. E.g., instead of using a GIF image to represent the Greek letter rho, the character entity ρ is used instead. Images were originally used because HTML browsers typically didn't support character entities for many of the symbols that were used. Current-generation browsers, however, are much better. Mozilla Firefox 1.0.7 supports all the character entities used in the CGNS documentation, and Microsoft Internet Explorer 6.0 supports all but a couple. See the list of standard HTML 4.0 character entities for Symbols and Greek Letters external link to see how they are displayed in your browser.
17 Nov 2005
  • Corrected typos in the Solution Data section of the Mid-Level Library manual. (GridLocation_t was mistakenly written as GridLocationType_t.)
16 Nov 2005
  • Corrected a minor cross-referencing error in the PDF version of the SIDS document.
2 Nov 2005
  • In the description of the Generalized Connectivity routines in the Mid-Level Library Manual, clarified the definitions of ndata_donor and donor_data.
19 Oct 2005
18 Oct 2005
  • Added a couple of sentences in the Multizone Interface Connectivity and Boundary Conditions sections of the SIDS document to clarify that a given zone boundary segment is intended to be defined as either a boundary condition segment or a multizone connectivity segment, but not both.
17 Oct 2005
  • Updated the Elements and Documentation section of the Overview and Entry-Level Document to reflect the option of using HDF instead of ADF. (Thanks to Chris Rumsey for doing the update.)
5 Oct 2005
  • Posted minutes from the Oct 4 CGNS Steering Committee telecon. (HTML, PDF).
  • Added ERF Paper 31-107, titled "Application of CGNS software components for helicopter blade fluid-structure strong coupling," by M. Poinot, M. Costes, and B. Cantaloube, presented at the 31st European Rotorcraft Forum, Florence, Italy. [PDF (174K, 10 pages)]
7 Sep 2005
  • In the History section of the Overview document, added a sentence crediting ONERA, ICEM CFD, and AEDC for the addition of support for HDF5.
6 Sep 2005
23 Aug 2005
  • Posted slides CFD General Notation System, an overview of the CGNS project and its current status, presented by Bruce Wedan of ANSYS/ICEM CFD at NASA Ames, Jan 2005. [PowerPoint (345K, 46 pages)].
  • In the Mid-Level Library manual, added a paragraph to the description of the function cg_bcdata_write about writing the boundary condition data itself.
14 Jul 2005
20 Jun 2005
6 Jun 2005
  • Posted minutes from the May 25 CGNS Steering Committee telecon. (HTML, PDF).
27 May 2005
  • Updated some links and contact points listed in the Applications Software section of the CGNS Overview and Entry-Level Document.
26 May 2005
  • Modified the Organization/Bylaws section of the CGNS Steering Committee Charter to allow the appointment of a Vice-Chairperson.
22 Mar 2005
  • Posted minutes from the Mar 16 CGNS Steering Committee telecon. (HTML, PDF).
4 Feb 2005
  • Added AIAA Paper 2005-1381, titled "Benchmarking Parallel I/O Performance for Computational Fluid Dynamics Applications," by P. D. Pakalapati and T. Hauser, presented at the 43rd AIAA Aerospace Sciences Meeting and Exhibit. [PDF (3.6M, 8 pages)]
24 Jan 2005
  • Corrected an error in the Mid-Level Library manual, in the description of the data conversion routines cg_conversion_write and cg_conversion_read. The scale and offset factors are stored in a two-element array, not as separate scalars.
  • Corrected an error in the SIDS document, in the Elements_t data structure examples. The examples included DataArray_t data structures defining ParentData for 3-D elements, where it doesn't apply.
  • In the list of CGNS-related conference papers, added R. Magnan as an author for AIAA Paper 2005-0334. Apologies for inadvertantly omitting him in the original update.
19 Jan 2005
  • Added AIAA Paper 2005-0334, titled "CGNS-Based Data Model for Turbine Blade Optimization," by H. Iepan, F. Guibault, M.-G. Vallet, and R. Magnan, presented at the 43rd AIAA Aerospace Sciences Meeting and Exhibit. [PDF (379K, 11 pages)]
18 Jan 2005
  • Posted minutes from the Jan 12 CGNS Steering Committee meeting. (HTML, PDF).
  • Added AIAA Paper 2005-1155, titled "Checking CFD interfaces in a multi-disciplinary workflow with an XML/CGNS compiler" by M. Poinot, E. Montreuil, and E. Henaux, presented at the 43rd AIAA Aerospace Sciences Meeting and Exhibit. [PDF (662K, 11 pages)]
19 Nov 2004
  • Corrected (as Marc Poinot put it) the "smallest typo ever known", in the "Deforming Grid Motion" example in the Time-Dependent Flow section of the SIDS document. Thanks to Marc for spotting this.
  • Modified the Steering Committee Charter to add Utah State University, Stanford University, and ANSYS-CFX as Steering Committee members.
  • Posted minutes from the Nov 17 CGNS Steering Committee telecon. (HTML, PDF).
20 Oct 2004
  • Corrected an error in the section on Unstructured Grid Element Numbering Conventions in the SIDS document. For pyramid elements, the oriented edges for face F4 were listed as E6,E8,-E7, and the correct values are E3,E8,-E7. Thanks to Alan Sayre for spotting this.
6 Oct 2004
30 Sep 2004
  • Posted minutes from the Sep 28 CGNS Steering Committee telecon. (HTML, PDF).
29 Sep 2004
  • Added files and instructions for downloading and using the LaTeX source for the CGNS documentation.
7 Jul 2004
  • Posted minutes from the June 30 CGNS Steering Committee meeting. (HTML, PDF).
  • Added AIAA Paper 2004-2142, titled "Impact of CGNS on CFD Workflow" by M. Poinot, C. L. Rumsey, and M. Mani, presented at the 34th AIAA Fluid Dynamics Conference and Exhibit. [PDF (729K, 12 pages)]
22 Jun 2004
  • Added AIAA Paper 2004-1088, titled "Parallel I/O for the CGNS system" by Th. Hauser, presented at the 42nd AIAA Aerospace Sciences Meeting and Exhibit. [PDF (1.5M, 11 pages)]
2 Jun 2004
  • Removed the wording "in the same manner as grid connectivity" in the description of the BC_t node in the SIDS-to-ADF File Mapping Manual, that was inadvertantly left in when the documentation was updated with the release of CGNS Version 2.3.
18 May 2004
  • Changed the description of Ordinal in the Mid-Level Library manual to say that it may be any integer value, and is not limited to values > 0.
2 Apr 2004
  • Posted minutes from the Mar 25 CGNS Steering Committee telecon. (HTML, PDF).
26 Mar 2004
  • Due to the release of CGNS Version 2.3, the CGNS documentation has been moved as shown below:
  • Documentation for CGNS Version 2.1 has been deleted.
  • Updated the Overview document to reflect the release of CGNS Version 2.3.
19 Mar 2004
  • Removed the web page showing access stats for the CGNS documentation web pages. The widespread use of indexing robots for search engines, and the local use of link validation tools, have made the access stats pretty meaningless.
13 Feb 2004
  • Changed the description of the BC_t data structure in the SIDS manual to reflect the addition of ElementRange and ElementList.
  • In the Mid-Level Library manual, modified the description of the routines related to the Boundary Condition Type and Location to reflect the addition of ElementRange and ElementList in the BC_t structure.
  • In the File Mapping manual, modified the BC_t figure to reflect the addition of ElementRange and ElementList.
  • In the User's Guide to CGNS, modified the "Getting Started" section to reflect the addition of ElementRange and ElementList in the BC_t structure.
29 Jan 2004
  • Changed names of some .gif files used in the HTML version of the SIDS document, to avoid file name conflicts on Windows systems, which (unfortunately) uses case-insensitive file names.
13 Jan 2004
24 Nov 2003
  • Posted minutes from the Nov 20 CGNS Steering Committee telecon. (HTML, PDF).
24 Sep 2003
  • Posted minutes from the Sep 18 CGNS Steering Committee telecon. (HTML, PDF).
12 Sep 2003
  • Corrected typos in the Grid Connectivity section of the Mid-Level Library manual. (GridLocation_t was mistakenly written as GridLocationType_t.)
4 Jun 2003
2 Jun 2003
  • Posted minutes from the May 29 CGNS Steering Committee telecon. (HTML, PDF).
20 May 2003
13 May 2003
29 Apr 2003
  • Added site maps for the major CGNS documents.
23 Apr 2003
  • A search capability has been added. Words and/or phrases may be searched for in a specific document, or in all documents combined.
27 Mar 2003
  • Added a paragraph about the CGNStalk mailing list, with a link to the list archive.
  • Modified the description of cg_goto in the Mid-Level Library manual to note that when accessing a BCData_t node, the index must be set to either Dirichlet or Neumann.
26 Mar 2003
  • Posted minutes from the Mar 20 CGNS Steering Committee telecon. (HTML, PDF).
20 Mar 2003
  • Added a sentence to the description of the ZoneBC_t data structure in the SIDS document to clarify that each boundary condition patch must be represented by a single BC_t data structure.
  • Expanded Note 2 for the BC_t data structure in the SIDS document, to add some discussion about the interpretation of the points defining a BC patch when GridLocation is set to Vertex.
28 Jan 2003
23 Jan 2003
22 Jan 2003
15 Jan 2003
  • Posted minutes from the Jan 6 CGNS Steering Committee meeting. (HTML, PDF).
10 Dec 2002
6 Dec 2002
  • Posted minutes from the Dec 4 CGNS Steering Committee telecon. (HTML, PDF).
26 Sep 2002
25 Sep 2002
20 Sep 2002
12 Sep 2002
6 Sep 2002
  • In the PDF version of the Mid-Level Library manual, corrected a typo in the definition of "A" in Section 8.1.
23 Aug 2002
20 Aug 2002
12 Aug 2002
  • In the PDF version of the Mid-Level Library manual, corrected error in the input/output labeling for fn in the cg_open, cg_version, and cg_close routines.
30 Jul 2002
  • Updated the Overview document to reflect the release of Version 2.1 of the CGNS software on May 24, 2002.
3 Jul 2002
  • Posted slides presented by John Steinbrenner of Pointwise, Inc., at the 8th International Conference on Numerical Grid Generation in Honolulu, Hawaii, June 2-6, 2002. [PDF (131K, 12 pages), PowerPoint (143K, 12 pages)].
2 Jul 2002
  • Posted minutes from the June 24 CGNS Steering Committee meeting. (HTML, PDF).
31 May 2002
  • Due to the release of production Version 2.1 of the CGNS software on May 24, the CGNS documentation has been moved as shown below:
23 May 2002
  • Corrected a minor error in the OversetHoles_t structure definition. PointRange and PointList are not both optional; one must be specified, but not both.
22 May 2002
  • Posted minutes from the May 15 CGNS Steering Committee telecon. (HTML, PDF).
20 May 2002
7 May 2002
  • Added the document version number and the applicable CGNS software release number to the home or title page for each of the CGNS documents. Also added the CGNS logo, and in the HTML version changed the heading color to match the logo.
  • Updated and reorganized the Overview and Entry-Level Document.
  • Modified the definition of NormalListFlag for the Boundary Condition Type and Location routines in the Mid-Level Library manual.
  • Added a list summarizing the change history for the CGNS documentation.
25 Mar 2002
20 Mar 2002
  • Posted minutes from the Mar 13 CGNS Steering Committee telecon. (HTML, PDF).
15 Mar 2002
13 Mar 2002
11 Mar 2002
  • Changed the three non-PDF slide presentations to PDF files, supplied by Diane Poirier. (Thanks, Diane!)
6 Mar 2002
  • Added a page with the monthly access statistics for the CGNS documentation web site.
14 Feb 2002
5 Feb 2002
4 Feb 2002
  • Changed the attachments to the minutes from the Jan 14 CGNS Steering Committee meeting to PDF files, supplied by Diane Poirier. (Thanks, Diane!)
31 Jan 2002
25 Jan 2002
  • Added AIAA Paper 2002-0752, titled "CFD General Notation System (CGNS): Status and Future Directions", presented at the 40th AIAA Aerospace Sciences Meeting and Exhibit. [PDF (289K, 13 pages)]
23 Jan 2002
14 Nov 2001
2 Nov 2001
1 Nov 2001
  • Added files and instructions for installing the HTML version of the CGNS documentation on a local system.
10 Oct 2001
26 Sep 2001
17 Sep 2001
6 Sep 2001
23 Aug 2001
21 Aug 2001
10 Jul 2001
  • In the Mid-Level Library manual, changed to a slanted red font for the output variables, to better distinguish them from the input variables.
27 Jun 2001
  • Corrected a minor bug in the Flow Solution Example in the SIDS manual. The nondimensionalization factor for the momentum in the example is sqrt(p*rho), not sqrt(p/rho), and the corresponding ConversionScale values for MomentumX and MomentumY are both 352.446.
17 Apr 2001
5 Apr 2001
14 Mar 2001
  • In the SIDS manual, added statements in the sections describing the BaseIterativeData_t and ZoneIterativeData_t data structures clarifying that iterative data stored in a CGNS database corresponds to values at the end of the associated iteration.
7 Mar 2001
  • In the SIDS manual, added a statement in the 2-D (Surface) Elements subsection clarifying the normal direction for 2-D unstructured grid elements.
  • In the SIDS manual, added a statement in the section on data-name identifiers for flowfield variables stating that for vector quantities, data-name identifiers for components in cylindrical and spherical coordinates are established, even when they're not explicitly listed.
6 Mar 2001
  • Included software change history in this "What's New?" page.
22 Feb 2001