CFD General Notation System
This document outlines a CGNS library designed to ease implementation of CGNS by providing developers with a collection of handy I/O functions. Since knowledge of the ADF (or HDF ) core routines is not required to use this library, it greatly facilitates the task of interfacing with CGNS.
The CGNS Mid-Level Library is based on the SIDS-to-ADF and SIDS-to-HDF file mapping manuals. It allows reading and writing all of the information described in that manual including grid coordinates, block interfaces, flow solutions, and boundary conditions. Use of the mid-level library functions insures efficient communication between the user application and the internal representation of the CGNS data.
It is assumed that the reader is familiar with the information in the CGNS Standard Interface Data Structures (SIDS), as well as the file mapping manuals. The reader is also strongly encouraged to read the User's Guide to CGNS, which contains coding examples using the Mid-Level Library to write and read simple files containing CGNS databases.
The PDF form of the CGNS Mid-Level Library manual (419K, 75 pages) was created using pdfTeX and the hyperref package, and is designed to be printed. The PDF file may be viewed and/or printed using a variety of freely available software packages, including Acrobat Reader , GhostScript , and xpdf . The HTML form is designed for interactive use, and the contents are listed below.
The complete CGNS Mid-Level Library document in HTML form is also available for installation on a local system. This is a gzip'ed tar file (42K, 349K gunzip'ed), and may be downloaded by clicking on the link while holding down the shift key, assuming your browser supports this capability. A dialogue box will appear for you to specify the directory and file name. To unpack the contents, do
gunzip -c midlevel.tar.gz | tar xvf -The files will be extracted and stored in the directory midlevel. Point your browser to the local file midlevel/index.html to display the CGNS Mid-Level Library home page. Note that this does not include the PDF form of the manual. Note also that some links, to other manuals, etc., may not work.