1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
|
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/xhtml;charset=UTF-8"/>
<meta http-equiv="X-UA-Compatible" content="IE=9"/>
<meta name="generator" content="Doxygen 1.9.1"/>
<meta name="viewport" content="width=device-width, initial-scale=1"/>
<title>HDF5: Discovering the Contents of an HDF5 File</title>
<link href="tabs.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript" src="jquery.js"></script>
<script type="text/javascript" src="dynsections.js"></script>
<link href="navtree.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript" src="resize.js"></script>
<script type="text/javascript" src="navtreedata.js"></script>
<script type="text/javascript" src="navtree.js"></script>
<link href="search/search.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript" src="search/searchdata.js"></script>
<script type="text/javascript" src="search/search.js"></script>
<script type="text/javascript">
/* @license magnet:?xt=urn:btih:cf05388f2679ee054f2beb29a391d25f4e673ac3&dn=gpl-2.0.txt GPL-v2 */
$(document).ready(function() { init_search(); });
/* @license-end */
</script>
<link href="doxygen.css" rel="stylesheet" type="text/css" />
<link href="hdf5doxy.css" rel="stylesheet" type="text/css">
<!-- <link href="hdf5doxy.css" rel="stylesheet" type="text/css"/>
-->
<script type="text/javascript" src="hdf5_navtree_hacks.js"></script>
</head>
<body>
<div style="background:#FFDDDD;font-size:120%;text-align:center;margin:0;padding:5px">Please, help us to better serve our user community by answering the following short survey: <a href="https://www.hdfgroup.org/website-survey/">https://www.hdfgroup.org/website-survey/</a></div>
<div id="top"><!-- do not remove this div, it is closed by doxygen! -->
<div id="titlearea">
<table cellspacing="0" cellpadding="0">
<tbody>
<tr style="height: 56px;">
<td id="projectlogo"><img alt="Logo" src="HDFG-logo.png"/></td>
<td id="projectalign" style="padding-left: 0.5em;">
<div id="projectname"><a href="https://www.hdfgroup.org">HDF5</a>
 <span id="projectnumber">1.14.4.1</span>
</div>
<div id="projectbrief">API Reference</div>
</td>
<td> <div id="MSearchBox" class="MSearchBoxInactive">
<span class="left">
<img id="MSearchSelect" src="search/mag_sel.svg"
onmouseover="return searchBox.OnSearchSelectShow()"
onmouseout="return searchBox.OnSearchSelectHide()"
alt=""/>
<input type="text" id="MSearchField" value="Search" accesskey="S"
onfocus="searchBox.OnSearchFieldFocus(true)"
onblur="searchBox.OnSearchFieldFocus(false)"
onkeyup="searchBox.OnSearchFieldChange(event)"/>
</span><span class="right">
<a id="MSearchClose" href="javascript:searchBox.CloseResultsWindow()"><img id="MSearchCloseImg" border="0" src="search/close.svg" alt=""/></a>
</span>
</div>
</td>
</tr>
</tbody>
</table>
</div>
<!-- end header part -->
<!-- Generated by Doxygen 1.9.1 -->
<script type="text/javascript">
/* @license magnet:?xt=urn:btih:cf05388f2679ee054f2beb29a391d25f4e673ac3&dn=gpl-2.0.txt GPL-v2 */
var searchBox = new SearchBox("searchBox", "search",false,'Search','.html');
/* @license-end */
</script>
</div><!-- top -->
<div id="side-nav" class="ui-resizable side-nav-resizable">
<div id="nav-tree">
<div id="nav-tree-contents">
<div id="nav-sync" class="sync"></div>
</div>
</div>
<div id="splitbar" style="-moz-user-select:none;"
class="ui-resizable-handle">
</div>
</div>
<script type="text/javascript">
/* @license magnet:?xt=urn:btih:cf05388f2679ee054f2beb29a391d25f4e673ac3&dn=gpl-2.0.txt GPL-v2 */
$(document).ready(function(){initNavTree('_l_b_contents.html',''); initResizable(); });
/* @license-end */
</script>
<div id="doc-content">
<!-- window showing the filter options -->
<div id="MSearchSelectWindow"
onmouseover="return searchBox.OnSearchSelectShow()"
onmouseout="return searchBox.OnSearchSelectHide()"
onkeydown="return searchBox.OnSearchSelectKey(event)">
</div>
<!-- iframe showing the search results (closed by default) -->
<div id="MSearchResultsWindow">
<iframe src="javascript:void(0)" frameborder="0"
name="MSearchResults" id="MSearchResults">
</iframe>
</div>
<div class="PageDoc"><div class="header">
<div class="headertitle">
<div class="title">Discovering the Contents of an HDF5 File </div> </div>
</div><!--header-->
<div class="contents">
<div class="textblock"><p>Navigate back: <a class="el" href="index.html">Main</a> / <a class="el" href="_getting_started.html">Getting Started with HDF5</a> / <a class="el" href="_learn_basics.html">Learning the Basics</a> </p><hr />
<h1><a class="anchor" id="secLBContents"></a>
Discovering what is in an HDF5 file</h1>
<p>HDFView and h5dump are standalone tools which cannot be called within an application, and using <a class="el" href="_h5version_8h.html#a7dba2e5b2045f31c0932123ffb54f7a3">H5Dopen</a> and <a class="el" href="group___h5_d.html#ga8287d5a7be7b8e55ffeff68f7d26811c" title="Reads raw data from a dataset into a provided buffer.">H5Dread</a> require that you know the name of the HDF5 dataset. How would an application that has no prior knowledge of an HDF5 file be able to determine or discover the contents of it, much like HDFView and h5dump?</p>
<p>The answer is that there are ways to discover the contents of an HDF5 file, by using the <a class="el" href="group___h5_g.html">Groups (H5G)</a>, <a class="el" href="group___h5_l.html">Links (H5L)</a> and <a class="el" href="group___h5_o.html">Objects (H5O)</a> APIs: </p><ul>
<li>The <a class="el" href="group___h5_g.html">Groups (H5G)</a> interface (covered earlier) consists of routines for working with groups. A group is a structure that can be used to organize zero or more HDF5 objects, not unlike a Unix directory. </li>
<li>The <a class="el" href="group___h5_l.html">Links (H5L)</a> interface consists of link routines. A link is a path between groups. The <a class="el" href="group___h5_l.html">Links (H5L)</a> interface allows objects to be accessed by use of these links. </li>
<li>The <a class="el" href="group___h5_o.html">Objects (H5O)</a> interface consists of routines for working with objects. Datasets, groups, and committed datatypes are all objects in HDF5.</li>
</ul>
<p>Interface routines that simplify the process: </p><ul>
<li><a class="el" href="group___t_r_a_v.html#ga55406698106930db68242987c11ba051">H5Literate</a> traverses the links in a specified group, in the order of the specified index, using a user-defined callback routine. (A callback function is one that will be called when a certain condition is met, at a certain point in the future.) </li>
<li><a class="el" href="group___h5_o.html#ga5ce86255fcc34ceaf84a62551cd24233">H5Ovisit</a> / <a class="el" href="group___t_r_a_v.html#gac0558936502924d9e898d8b6e041ed69">H5Lvisit</a> recursively visit all objects/links accessible from a specified object/group.</li>
</ul>
<h1><a class="anchor" id="secLBContentsProg"></a>
Programming Example</h1>
<h2><a class="anchor" id="subsecLBContentsProgUsing"></a>
Using #H5Literate, #H5Lvisit and #H5Ovisit</h2>
<p>For example code, see the <a class="el" href="_h_d_f5_examples.html">HDF5 Examples</a> page. Specifically look at the <a class="el" href="_ex_a_p_i.html">Examples by API</a>. There are examples for different languages, where examples of using <a class="el" href="group___t_r_a_v.html#ga55406698106930db68242987c11ba051">H5Literate</a> and <a class="el" href="group___h5_o.html#ga5ce86255fcc34ceaf84a62551cd24233">H5Ovisit</a>/<a class="el" href="group___t_r_a_v.html#gac0558936502924d9e898d8b6e041ed69">H5Lvisit</a> are included.</p>
<p>The h5ex_g_traverse example traverses a file using H5Literate: </p><ul>
<li>C: <a href="https://support.hdfgroup.org/ftp/HDF5/examples/examples-by-api/hdf5-examples/1_8/C/H5G/h5ex_g_traverse.c">h5ex_g_traverse.c</a> </li>
<li>F90: <a href="https://support.hdfgroup.org/ftp/HDF5/examples/examples-by-api/hdf5-examples/1_8/FORTRAN/H5G/h5ex_g_traverse_F03.f90">h5ex_g_traverse_F03.f90</a></li>
</ul>
<p>The h5ex_g_visit example traverses a file using H5Ovisit and H5Lvisit: </p><ul>
<li>C: <a href="https://support.hdfgroup.org/ftp/HDF5/examples/examples-by-api/hdf5-examples/1_8/C/H5G/h5ex_g_visit.c">h5ex_g_visit.c</a> </li>
<li>F90: <a href="https://support.hdfgroup.org/ftp/HDF5/examples/examples-by-api/hdf5-examples/1_8/FORTRAN/H5G/h5ex_g_visit_F03.f90">h5ex_g_visit_F03.f90</a></li>
</ul>
<hr />
<p> Navigate back: <a class="el" href="index.html">Main</a> / <a class="el" href="_getting_started.html">Getting Started with HDF5</a> / <a class="el" href="_learn_basics.html">Learning the Basics</a> </p>
</div></div><!-- contents -->
</div><!-- PageDoc -->
</div><!-- doc-content -->
<!-- start footer part -->
<div id="nav-path" class="navpath"><!-- id is needed for treeview function! -->
<ul>
<li class="footer">Generated by
<a href="http://www.doxygen.org/index.html">
<img class="footer" src="doxygen.png" alt="doxygen"/></a> 1.9.1 </li>
</ul>
</div>
</body>
</html>
|
