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<div><div class="header">
  <div class="headertitle"><div class="title">Programming Issues</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  />
<p>Keep the following in mind when looking at the example programs included in this tutorial:</p>
<h1><a class="anchor" id="LBProgAPI"></a>
APIs vary with different languages</h1>
<ul>
<li>C routines begin with the prefix “H5*” where * is a single letter indicating the object on which the operation is to be performed: <table class="doxtable">
<tr>
<td>File Interface:  </td><td><a class="el" href="group___h5_f.html#gaa3f4f877b9bb591f3880423ed2bf44bc" title="Opens an existing HDF5 file.">H5Fopen</a> </td></tr>
<tr>
<td>Dataset Interface: </td><td><a class="el" href="_h5version_8h.html#a7dba2e5b2045f31c0932123ffb54f7a3">H5Dopen</a>  </td></tr>
</table>
</li>
</ul>
<ul>
<li>FORTRAN routines begin with “h5*” and end with “_f”: <table class="doxtable">
<tr>
<td>File Interface:  </td><td><a class="el" href="group___f_h5_f.html#gae9fa6f0b685c0e1516b7924dcb0e8819" title="Opens HDF5 file.">h5f.h5fopen_f</a> </td></tr>
<tr>
<td>Dataset Interface: </td><td><a class="el" href="group___f_h5_d.html#ga56db335650709fe67bbfbc5a46ff4abf" title="Opens an existing dataset.">h5d.h5dopen_f</a>  </td></tr>
</table>
</li>
</ul>
<ul>
<li>Java routine names begin with “H5*” and are prefixed with “H5.” as the class. Constants are in the HDF5Constants class and are prefixed with "HDF5Constants.".: <table class="doxtable">
<tr>
<td>File Interface:  </td><td>H5.H5Fopen </td></tr>
<tr>
<td>Dataset Interface: </td><td>H5.H5Dopen  </td></tr>
</table>
</li>
</ul>
<ul>
<li>APIS for languages like C++, Java, and Python use methods associated with specific objects.</li>
</ul>
<h1><a class="anchor" id="LBProgTypes"></a>
HDF5 library has its own defined types</h1>
<ul>
<li><a class="el" href="_h5_ipublic_8h.html#a0045db7ff9c22ad35db6ae91662e1943">hid_t</a> is used for object handles </li>
<li><a class="el" href="_h5public_8h.html#a7f81cce70fb546af88da24d9285d3c1c">hsize_t</a> is used for dimensions </li>
<li><a class="el" href="_h5public_8h.html#a3b079ecf932a5c599499cf7e298af160">herr_t</a> is used for many return values</li>
</ul>
<h1><a class="anchor" id="LBProgLang"></a>
Language specific files must be included in applications</h1>
<ul>
<li>
<b>Python</b>:<br  />
 <code> import h5py<br  />
 import numpy </code>  </li>
<li>
<b>C</b>:<br  />
 <code>"#include hdf5.h"</code>  </li>
<li>
<b>FORTRAN</b>:<br  />
 <code>USE HDF5</code><br  />
 and call <a class="el" href="group___f_h5.html#ga3ca54ba860cf80a39bcaef71484f5baf" title="Initializes HDF5 Fortran interface.">h5lib.h5open_f</a> and <a class="el" href="group___f_h5.html#gaaae21753ce0b3ef8eeb85720ac705d88" title="Closes HDF5 Fortran interface.">h5lib.h5close_f</a> to initialize and close the HDF5 FORTRAN interface  </li>
<li>
<b>Java</b>:<br  />
 <code> import <a class="el" href="classhdf_1_1hdf5lib_1_1_h5.html">hdf.hdf5lib.H5</a>;<br  />
 import <a class="el" href="classhdf_1_1hdf5lib_1_1_h_d_f5_constants.html">hdf.hdf5lib.HDF5Constants</a>; </code>  </li>
</ul>
<dl class="section see"><dt>See also</dt><dd><a class="el" href="_ex_a_p_i.html">Examples by API</a> for examples of using the HDF5 API.</dd></dl>
<hr  />
<p> Previous Chapter <a class="el" href="_l_b_a_p_i.html">The HDF5 API</a> - Next Chapter <a class="el" href="_l_b_file_create.html">Creating an HDF5 File</a></p>
<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>
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