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diff --git a/doc/html/Tutor/glossary.html b/doc/html/Tutor/glossary.html deleted file mode 100644 index 6105150..0000000 --- a/doc/html/Tutor/glossary.html +++ /dev/null @@ -1,261 +0,0 @@ -<HTML><HEAD> -<TITLE>HDF5 Tutorial - Glossary -</TITLE> -</HEAD> - -<body bgcolor="#ffffff"> - -<!-- BEGIN MAIN BODY --> - - - [ <A HREF="title.html"><I>HDF5 Tutorial Top</I></A> ] -<H1> -<BIG><BIG><BIG><FONT COLOR="#c101cd">Glossary</FONT> -</BIG></BIG></BIG></H1> - -<hr noshade size=1> - -<BODY> -<DL> -<DT><B>ATTRIBUTE</B> -<DD>An HDF5 attribute is a small dataset that can be used to describe - the nature and/or the intended usage of the object it is attached - to. - -<P> -<DT><B>BOOT BLOCK</B> -<DD>HDF5 files are composed of a "boot block" describing information required to portably access files on multiple platforms, followed by information -about the groups in a file and the datasets in the file. The boot block contains information about the size of offsets and lengths of objects, the -number of entries in symbol tables (used to store groups) and additional version information for the file. -<P> -<DT><B>DATASET</B> -<DD>An HDF5 dataset is a multi-dimensional array of data elements, - together with supporting metadata. - -<P> -<DT><B>DATASPACE</B> -<DD>An HDF5 dataspace is an object that describes the dimensionality - of the data array. A dataspace is either a regular N-dimensional - array of data points, called a simple dataspace, or a more - general collection of data points organized in another - manner, called a complex dataspace. - -<P> -<DT><B>DATATYPE</B> -<DD>An HDF5 Datatype is an object that describes the type of the - element in an HDF5 multi-dimensional array. There are two - categories of datatypes: atomic and compound data types. An - atomic type is a type which cannot be decomposed into smaller - units at the API level. A compound is a collection of one or - more atomic types or small arrays of such types. - -<P> -<DT><B>DATASET CREATION PROPERTY LIST</B> -<DD> The Dataset Creation Property List contains information on how - raw data is organized on disk and how the raw data is compressed. - The dataset API partitions these terms by layout, compression, - and external storage: -<UL> -<B> Layout:</B> -<UL> -<LI> H5D_COMPACT: Data is small and can be stored in object header (not - implemented yet). This eliminates disk seek/read requests. -<LI> H5D_CONTIGUOUS: (<B>default</B>) The data is large, non-extendible, - non-compressible, non-sparse, and can be stored - externally. -<LI> H5D_CHUNKED: The data is large and can be extended in any dimension. - It is partitioned into chunks so each chunk is the same - logical size. -</UL> -<B>Compression:</B> (gzip compression)<BR> -<B>External Storage Properties:</B> The data must be contiguous to be stored - externally. It allows you to store the data - in one or more non-HDF5 files. - -</UL> - -<P> -<DT><B>DATA TRANSFER PROPERTY LIST</B> -<DD> The data transfer property list is used to control various aspects - of the I/O, such as caching hints or collective I/O information. -<P> -<DT><B>DDL</B> -<DD>DDL is a Data Description Language that describes HDF5 objects - in Backus-Naur Form. - -<P> - -<DT><B>FILE ACCESS MODES</B> -<DD>The file access modes determine whether an existing file will be -overwritten. All newly created files are opened for both reading and -writing. Possible values are: -<PRE> - H5F_ACC_RDWR: Allow read and write access to file. - H5F_ACC_RDONLY: Allow read-only access to file. - H5F_ACC_TRUNC: Truncate file, if it already exists, erasing all data - previously stored in the file. - H5F_ACC_EXCL: Fail if file already exists. - H5F_ACC_DEBUG: Print debug information. - H5P_DEFAULT: Apply default file access and creation properties. -</PRE> -<P> -<DT><B>FILE ACCESS PROPERTY LIST</B> - <DD> File access property lists are used to control different methods - of performing I/O on files: -<UL> -<B>Unbuffered I/O:</B> Local permanent files can be accessed with the functions - described in Section 2 of the Posix manual, namely open(), lseek(), read(), - write(), and close(). <BR> -<B>Buffered I/O:</B> Local permanent files can be accessed with the functions - declared in the stdio.h header file, namely fopen(), fseek(), fread(), - fwrite(), and fclose().<BR> -<B>Memory I/O:</B> Local temporary files can be created and accessed directly from - memory without ever creating permanent storage. The library uses malloc() - and free() to create storage space for the file<BR> -<B>Parallel Files using MPI I/O:</B> This driver allows parallel access to a file - through the MPI I/O library. The parameters which can be modified are the - MPI communicator, the info object, and the access mode. The communicator - and info object are saved and then passed to MPI_File_open() during file - creation or open. The access_mode controls the kind of parallel access the - application intends.<BR> -<B>Data Alignment:</B> Sometimes file access is faster if certain things are aligned - on file blocks. This can be controlled by setting alignment properties of - a file access property list with the H5Pset_alignment() function. -</UL> -<P> -<DT><B>FILE CREATION PROPERTY LIST</B> -<DD> The file creation property list is used to control the file - metadata. The parameters that can be modified are: -<UL> - <B>User-Block Size:</B> The "user-block" is a fixed length block of data located - at the beginning of the file which is ignored by the HDF5 library and may - be used to store any data information found to be useful to applications. -<BR> -<B> Offset and Length Sizes:</B> The number of bytes used to store the offset and - length of objects in the HDF5 file can be controlled with this parameter. - Symbol Table Parameters: The size of symbol table B-trees can be controlled - by setting the 1/2 rank and 1/2 node size parameters of the B-tree. -<BR> -<B> Indexed Storage Parameters:</B> The size of indexed storage B-trees can be - controlled by setting the 1/2 rank and 1/2 node size parameters of the - B-tree. -</UL> -<P> - -<DT><B>GROUP</B> -<DD>A Group is a structure containing zero or more HDF5 objects, - together with supporting metadata. The two primary HDF5 objects - are datasets and groups. -<P> - -<DT><B>HDF5</B> -<DD>HDF5 is an abbreviation for Hierarchical Data Format Version 5. - This file format is intended to make it easy to write and read - scientific data -<P> -<UL> - <LI> by including the information needed to understand the data - within the file -<P> - <LI> by providing a library of C, FORTRAN, and other language - programs that reduce the work required to provide efficient - writing and reading - even with parallel IO -</UL> -<P> - -<DT><B>HDF5 FILE</B> -<DD>An HDF5 file is a container for storing grouped collections - of multi-dimensional arrays containing scientific data. -<P> - -<DT><B>H5DUMP</B> -<DD>h5dump is an HDF5 tool that describes the HDF5 file contents in DDL. -<P> - -<DT><B>HYPERSLAB</B> -<DD> -A hyperslab is a portion of a dataset. A hyperslab selection can be a -logically contiguous collection of points in a dataspace, or it -can be a regular pattern of points or blocks in a dataspace. -<P> -<DT><B>MOUNTING FILES</B> -<DD> -HDF5 allows you to combine two or more HDF5 files in a manner similar -to mounting files in UNIX. The group structure and metadata -from one file appear as though they exist in another file. -<P> - -<DT><B>NAMES</B> -<DD>HDF5 object names are a slash-separated list of components. A name - which begins with a slash is an absolute name which is accessed - beginning with the root group of the file while all other relative - names are accessed beginning with the specified group. -<P> -<DT><B>PARALLEL I/O (HDF5)</B> -<DD>The parallel I/O version of HDF5 supports parallel file access using -MPI (Message Passing Interface). -<P> - -<DT><B>REFERENCE</B> -<DD> -<B>OBJECT REFERENCE:</B><BR> - A reference to an entire object in the current HDF5 file. - <P> - An object - reference points to an entire object in the current HDF5 file by storing - the relative file address (OID) of the object header for the object - pointed to. The relative file address of an object header is constant - for the life of the object. An object reference is of a fixed size in - the file. -<P> -<B>DATASET REGION REFERENCE:</B><BR> - Reference to a specific dataset region. - <P> - A dataset region reference points to a region of a dataset in the - current HDF5 file by storing the OID of the dataset and the global - heap offset of the region referenced. The region referenced is - located by retrieving the coordinates of the areas in the region - from the global heap. A dataset region reference is of a variable - size in the file. -<P> -<DT><B>THREADSAFE (HDF5)</B> -<DD>A "thread-safe" version of HDF-5 (TSHDF5) is one that can be called from any thread of a multi-threaded program. Any calls to HDF -can be made in any order, and each individual HDF call will perform correctly. A calling program does not have to explicitly lock the HDF -library in order to do I/O. Applications programmers may assume that the TSHDF5 guarantees the following: -<UL> - <LI> the HDF-5 library does not create or destroy threads. - <LI> the HDF-5 library uses modest amounts of per-thread private memory. - <LI> the HDF-5 library only locks/unlocks it's own locks (no locks are passed in or returned from HDF), and the internal locking is guaranteed to be deadlock free. -</UL> -<P> -These properties mean that the TSHDF5 library will not interfere with an application's use of threads. A TSHDF5 library is the same -library as regular HDF-5 library, with additional code to synchronize access to the HDF-5 library's internal data structures. - -</DL> - -<!-- BEGIN FOOTER INFO --> - -<P><hr noshade size=1> -<font face="arial,helvetica" size="-1"> - <a href="http://www.ncsa.uiuc.edu/"><img border=0 -src="footer-ncsalogo.gif" - width=78 height=27 alt="NCSA"><br> - The National Center for Supercomputing Applications</A><br> - <a href="http://www.uiuc.edu/">University of Illinois - at Urbana-Champaign</a><br> - <br> -<!-- <A HREF="helpdesk.mail.html"> --> -<A HREF="mailto:hdfhelp@ncsa.uiuc.edu"> -hdfhelp@ncsa.uiuc.edu</A> -<br> -<BR> <H6>Last Modified: June 22, 2001</H6><BR> -<!-- modified by Barbara Jones - bljones@ncsa.uiuc.edu --> -</FONT> -<BR> -<!-- <A HREF="mailto:hdfhelp@ncsa.uiuc.edu"> --> - -</BODY> -</HTML> - - - |