diff options
| author | Frank Baker <fbaker@hdfgroup.org> | 2000-12-22 20:47:59 (GMT) |
|---|---|---|
| committer | Frank Baker <fbaker@hdfgroup.org> | 2000-12-22 20:47:59 (GMT) |
| commit | c1d537db2b803d6908fe3f21f62c592c9cd2bf70 (patch) | |
| tree | 56a6cb7f00a6fbec3b071722df9705e744368073 /doc/html/Tutor/crtgrp.html | |
| parent | d4c3773742b8dee426e7325fee4e8fc4015f2802 (diff) | |
| download | hdf5-c1d537db2b803d6908fe3f21f62c592c9cd2bf70.zip hdf5-c1d537db2b803d6908fe3f21f62c592c9cd2bf70.tar.gz hdf5-c1d537db2b803d6908fe3f21f62c592c9cd2bf70.tar.bz2 | |
[svn-r3196]
Purpose:
Adding Tutorial to development branch (R 1.4)
Platforms tested:
IE 5
Diffstat (limited to 'doc/html/Tutor/crtgrp.html')
| -rw-r--r-- | doc/html/Tutor/crtgrp.html | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/doc/html/Tutor/crtgrp.html b/doc/html/Tutor/crtgrp.html new file mode 100644 index 0000000..566fd2c --- /dev/null +++ b/doc/html/Tutor/crtgrp.html @@ -0,0 +1,167 @@ +<HTML><HEAD> +<TITLE>HDF5 Tutorial - Creating a Group +</TITLE> +</HEAD> + +<body bgcolor="#ffffff"> + +<!-- BEGIN MAIN BODY --> + +<A HREF="http://www.ncsa.uiuc.edu/"><img border=0 +src="http://www.ncsa.uiuc.edu/Images/NCSAhome/footerlogo.gif" +width=78 height=27 alt="NCSA"><P></A> + + + [ <A HREF="title.html"><I>HDF5 Tutorial Top</I></A> ] +<H1> +<BIG><BIG><BIG><FONT COLOR="#c101cd">Creating a Group</FONT> +</BIG></BIG></BIG></H1> + +<hr noshade size=1> + +<BODY> +<H2>Contents:</H2> +<UL> + <LI> <A HREF="#def">What is a Group</A>? + <LI> Programming Example + <UL> + <LI> <A HREF="#desc">Description</A> + <LI> <A HREF="#rem">Remarks</A> + <LI> <A HREF="#fc">File Contents</A> + </UL> +</UL> +<HR> +<A NAME="def"> +<H2>What is a Group?</h2> +<P> +An HDF5 group is a structure containing zero or more HDF5 objects. The two +primary HDF5 objects are groups and datasets. To create a group, the calling +program must: +<OL> + <LI> Obtain the location identifier where the group is to be created. + <LI> Create the group. + <LI> Close the group. +</OL> +To create a group, the calling program must contain the following calls: +<PRE> + group_id = H5Gcreate (loc_id, name, size_hint); + H5Gclose (group_id); +</PRE> + + + + +<P> +<H2> Programming Example</H2> +<A NAME="desc"> +<H3><U>Description</U></H3> +The following example shows how to create and close a group. It creates a file +called 'group.h5', creates a group called <I>MyGroup</I> in the root group, +and then closes the group and file. <BR> +[ <A HREF="examples/h5_crtgrp.c">Download h5_crtgrp.c</A> ] +<PRE> + ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ + +#include <hdf5.h> +#define FILE "group.h5" + +main() { + + hid_t file_id, group_id; /* identifiers */ + herr_t status; + + /* Create a new file using default properties. */ + file_id = H5Fcreate(FILE, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT); + + /* Create a group named "/MyGroup" in the file. */ + group_id = H5Gcreate(file_id, "/MyGroup", 0); + + /* Close the group. */ + status = H5Gclose(group_id); + + /* Terminate access to the file. */ + status = H5Fclose(file_id); +} +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ +</PRE> +<A NAME="rem"> +<H3><U>Remarks</U></H3> +<UL> +<LI> H5Gcreate creates a new empty group and returns a group identifier. +<PRE> + hid_t H5Gcreate (hid_t loc_id, const char *name, size_t size_hint) +</PRE> +<UL> + <LI> The first parameter specifies the location to create the group. + + <LI> The second parameter specifies the name of the group to be created. + + <LI> The third parameter specifies how much file space to reserve to store the + names that will appear in the group. If a non-positive value is supplied, + then a default size is used. Passing a value of zero is usually adequate + since the library is able to dynamically resize the name heap. +</UL> +<P> +<LI> H5Gcreate creates a group named <I>MyGroup</I> in the root group of the specified + file. +<P> +<LI> H5Gclose closes the group. This call is mandatory. +<PRE> + herr_t H5Gclose (hid_t group_id) +</PRE> +</UL> + +<A NAME="fc"> +<H3><U>File Contents</U></H3> +The contents of 'group.h5' and the definition of the group are given in the +following: +<P> +<table width="56%" border="1" bordercolor="#FFFFFF" cellpadding="6" cellspacing="6"> + <tr> + <td width="47%"><b>Fig. 8.1</b> <i>The Contents of 'group.h5'.</i> + </td> + <td width="53%"><b>Fig. 8.2</b> <i>'group.h5' in DDL</i> </td> + </tr> + <tr bordercolor="#000000"> +<!-- <td width="47%"><IMG src="grouph5.jpg" width="205" height="333"></td> --> + <td width="47%"><IMG src="img003.gif"></td> + <td width="53%" valign="top"> + <pre> +HDF5 "group.h5" { +GROUP "/" { + GROUP "MyGroup" { + } +} +} +</pre> + </td> + </tr> +</table> + + +<!-- 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="http://www.ncsa.uiuc.edu/Images/NCSAhome/footerlogo.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> <H6>Last Modified: August 27, 1999</H6><BR> +<!-- modified by Barbara Jones - bljones@ncsa.uiuc.edu --> +</FONT> +<BR> +<!-- <A HREF="mailto:hdfhelp@ncsa.uiuc.edu"> --> + +</BODY> +</HTML> + + + |