mirrors/hdf5
2
0
Fork 0
mirror of https://github.com/HDFGroup/hdf5.git synced 2026-09-25 04:09:44 +03:00
Code Issues Packages Projects Releases Wiki Activity
Files
ea9038e9f7cd7df6c71b8035cc765f268600a974
hdf5/develop/_l_b_com_dset.html
T
byrnHDF ea9038e9f7 deploy: 780f6e40de
2026-09-02 01:23:41 +00:00

185 lines
10 KiB
HTML
Raw Blame History

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "https://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=11"/>
<meta name="generator" content="Doxygen 1.16.1"/>
<meta name="viewport" content="width=device-width, initial-scale=1"/>
<title>HDF5: Compressed Datasets</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="navtreedata.js"></script>
<script type="text/javascript" src="navtree.js"></script>
<script type="text/javascript" src="cookie.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">
$(function() { init_search(); });
</script>
<link href="doxygen.css" rel="stylesheet" type="text/css" />
<link href="hdf5doxy.css" rel="stylesheet" type="text/css"/>
<link href="doxygen-awesome.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>
<div style="background:#FFDDDD;font-size:120%;text-align:center;margin:0;padding:5px">Help us improve by taking our short survey: <a href="https://www.hdfgroup.org/website-survey/">https://www.hdfgroup.org/website-survey/</a></div>
<!-- ... other metadata & script includes ... -->
<script type="text/javascript" src="doxygen-awesome-tabs.js"></script>
<script type="text/javascript">
DoxygenAwesomeTabs.init()
</script>
<!-- Google tag (gtag.js) -->
<script async src="https://www.googletagmanager.com/gtag/js?id=G-57FMZK4S7X"></script>
<script>
window.dataLayer = window.dataLayer || [];
function gtag(){dataLayer.push(arguments);}
gtag('js', new Date());
gtag('config', 'G-57FMZK4S7X');
</script>
</head>
<body>
<div id="top"><!-- do not remove this div, it is closed by doxygen! -->
<div id="titlearea">
<table cellspacing="0" cellpadding="0">
<tbody>
<tr id="projectrow">
<td id="projectlogo"><img alt="Logo" src="HDFG-logo.png"/></td>
<td id="projectalign">
<div id="projectname">HDF5<span id="projectnumber">&#160;Last Updated on 2026-09-02</span>
</div>
<div id="projectbrief">The HDF5 Field Guide</div>
</td>
</tr>
</tbody>
</table>
</div>
<!-- end header part -->
<!-- Generated by Doxygen 1.16.1 -->
<script type="text/javascript">
var searchBox = new SearchBox("searchBox", "search/",'.html');
</script>
<script type="text/javascript">
$(function() { codefold.init(); });
</script>
<div id="main-nav">
<div id="navrow1" class="tabs">
<ul class="tablist">
<li><a href="index.html"><span>Main&#160;Page</span></a></li>
<li><a href="_getting_started.html"><span>Getting&#160;started</span></a></li>
<li><a href="_u_g.html"><span>User&#160;Guide</span></a></li>
<li><a href="_r_m.html"><span>Reference&#160;Manual</span></a></li>
<li><a href="_cookbook.html"><span>Cookbook</span></a></li>
<li><a href="_t_n.html"><span>Technical&#160;Notes</span></a></li>
<li><a href="_r_f_c.html"><span>RFCs</span></a></li>
<li><a href="_s_p_e_c.html"><span>Specifications</span></a></li>
<li><a href="_g_l_s.html"><span>Glossary</span></a></li>
<li><a href="_f_t_s.html"><span>Full-Text&#160;Search</span></a></li>
<li><a href="_about.html"><span>About</span></a></li>
<li>
<div id="MSearchBox" class="MSearchBoxInactive">
<span class="left">
<span id="MSearchSelect" class="search-icon" onmouseover="return searchBox.OnSearchSelectShow()" onmouseout="return searchBox.OnSearchSelectHide()"><span class="search-icon-dropdown"></span></span>
<input type="text" id="MSearchField" value="" placeholder="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()"><div id="MSearchCloseImg" class="close-icon"></div></a>
</span>
</div>
</li>
</ul>
</div>
</div><!-- main-nav -->
</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">
$(function(){initNavTree('_l_b_com_dset.html','',''); });
</script>
<div id="container">
<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">
<div id="MSearchResults">
<div class="SRPage">
<div id="SRIndex">
<div id="SRResults"></div>
<div class="SRStatus" id="Loading">Loading...</div>
<div class="SRStatus" id="Searching">Searching...</div>
<div class="SRStatus" id="NoMatches">No Matches</div>
</div>
</div>
</div>
</div>
<div><div class="header">
<div class="headertitle"><div class="title">Compressed Datasets </div></div>
</div><!--header-->
<div class="contents">
<div class="textblock"><p>Navigate back: <a class="el" href="index.html" title="notitle">Main</a> / <a class="el" href="_getting_started.html" title="Getting Started with HDF5">Getting Started with HDF5</a> / <a class="el" href="_learn_basics.html" title="Learning the Basics">Learning the Basics</a> </p><hr />
<h1 class="doxsection"><a class="anchor" id="secLBComDsetCreate"></a>
Creating a Compressed Dataset</h1>
<p>HDF5 requires you to use chunking to create a compressed dataset. (To use chunking efficiently, be sure to see the advanced topic, <a class="el" href="hdf5_chunking.html" title="Chunking in HDF5">Chunking in HDF5</a>.)</p>
<p>The following operations are required in order to create a compressed dataset: </p><ul>
<li>Create a dataset creation property list. </li>
<li>Modify the dataset creation property list instance to enable chunking and to enable compression. </li>
<li>Create the dataset. </li>
<li>Close the dataset creation property list and dataset.</li>
</ul>
<p>For more information on troubleshooting compression issues, see <a class="el" href="_comp_t_s.html" title="HDF5 Compression Troubleshooting">HDF5 Compression Troubleshooting</a>.</p>
<h1 class="doxsection"><a class="anchor" id="secLBComDsetProg"></a>
Programming Example</h1>
<h2 class="doxsection"><a class="anchor" id="subsecLBComDsetProgDesc"></a>
Description</h2>
<p>See <a class="el" href="_l_b_examples.html" title="Examples from Learning the Basics">Examples from Learning the Basics</a> for the examples used in the <a class="el" href="_learn_basics.html" title="Learning the Basics">Learning the Basics</a> tutorial.</p>
<p>The example creates a chunked and ZLIB compressed dataset. It also includes comments for what needs to be done to create an SZIP compressed dataset. The example then reopens the dataset, prints the filter information, and reads the dataset.</p>
<p>For details on compiling an HDF5 application: [ <a class="el" href="_l_b_compiling.html" title="Compiling HDF5 Applications">Compiling HDF5 Applications</a> ]</p>
<h2 class="doxsection"><a class="anchor" id="subsecLBComDsetProgRem"></a>
Remarks</h2>
<ul>
<li>The <a class="el" href="group___d_c_p_l.html#ga3584d592e377da3604b7604e266dcf5b" title="Sets the size of the chunks used to store a chunked layout dataset.">H5Pset_chunk</a> call modifies a Dataset Creation Property List instance to store a chunked layout dataset and sets the size of the chunks used. </li>
<li>The <a class="el" href="group___d_c_p_l.html#gaf1f569bfc54552bdb9317d2b63318a0d" title="Sets deflate (GNU gzip) compression method and compression level.">H5Pset_deflate</a> call modifies the Dataset Creation Property List instance to use ZLIB or DEFLATE compression. The <a class="el" href="group___d_c_p_l.html#ga37de4b6071a94574cfab5cd6de9c3fc6" title="Sets up use of the SZIP compression filter.">H5Pset_szip</a> call modifies it to use SZIP compression. There are different compression parameters required for each compression method. </li>
<li>SZIP compression can only be used with atomic datatypes that are integer, float, or char. It cannot be applied to compound, array, variable-length, enumerations, or other user-defined datatypes. The call to <a class="el" href="group___h5_d.html#ga0647ba4bbd26d5230cc07f3a5685b2cf">H5Dcreate</a> will fail if attempting to create an SZIP compressed dataset with a non-allowed datatype. The conflict can only be detected when the property list is used.</li>
</ul>
<hr />
<p> Previous Chapter <a class="el" href="_l_b_ext_dset.html" title="Extendible Datasets">Extendible Datasets</a> - Next Chapter <a class="el" href="_l_b_contents.html" title="Discovering the Contents of an HDF5 File">Discovering the Contents of an HDF5 File</a></p>
<p>Navigate back: <a class="el" href="index.html" title="notitle">Main</a> / <a class="el" href="_getting_started.html" title="Getting Started with HDF5">Getting Started with HDF5</a> / <a class="el" href="_learn_basics.html" title="Learning the Basics">Learning the Basics</a> </p>
</div></div><!-- contents -->
</div><!-- PageDoc -->
</div><!-- doc-content -->
<div id="page-nav" class="page-nav-panel">
<div id="page-nav-resize-handle"></div>
<div id="page-nav-tree">
<div id="page-nav-contents">
</div><!-- page-nav-contents -->
</div><!-- page-nav-tree -->
</div><!-- page-nav -->
</div><!-- container -->
<!-- start footer part -->
<div id="nav-path" class="navpath"><!-- id is needed for treeview function! -->
<ul>
<li class="navelem"><a href="_learn_basics.html">Learning the Basics</a></li>
<li class="footer">Generated by <a href="https://www.doxygen.org/index.html"><img class="footer" src="doxygen.svg" width="104" height="31" alt="doxygen"/></a> 1.16.1 </li>
</ul>
</div>
</body>
</html>
Reference in New Issue View Git Blame Copy Permalink