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<a name="Cell-Arrays-with-Mex_002dFiles"></a>
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<p>
Next: <a href="Structures-with-Mex_002dFiles.html#Structures-with-Mex_002dFiles" accesskey="n" rel="next">Structures with Mex-Files</a>, Previous: <a href="Character-Strings-in-Mex_002dFiles.html#Character-Strings-in-Mex_002dFiles" accesskey="p" rel="prev">Character Strings in Mex-Files</a>, Up: <a href="Mex_002dFiles.html#Mex_002dFiles" accesskey="u" rel="up">Mex-Files</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p>
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<a name="Cell-Arrays-with-Mex_002dFiles-1"></a>
<h4 class="subsection">A.2.4 Cell Arrays with Mex-Files</h4>
<p>One can perform exactly the same operations on Cell arrays in mex-files
as in oct-files. An example that reduplicates the function of
the <samp>celldemo.cc</samp> oct-file in a mex-file is given by <samp>mycell.c</samp>
as shown below.
</p>
<div class="example">
<pre class="verbatim">#include "mex.h"
void
mexFunction (int nlhs, mxArray* plhs[],
int nrhs, const mxArray* prhs[])
{
mwSize n;
mwIndex i;
if (nrhs != 1 || ! mxIsCell (prhs[0]))
mexErrMsgTxt ("ARG1 must be a cell");
n = mxGetNumberOfElements (prhs[0]);
n = (n > nlhs ? nlhs : n);
for (i = 0; i < n; i++)
plhs[i] = mxDuplicateArray (mxGetCell (prhs[0], i));
}
</pre><pre class="example">
</pre></div>
<p>The output is identical to the oct-file version as well.
</p>
<div class="example">
<pre class="example">[b1, b2, b3] = mycell ({1, [1, 2], "test"})
⇒
b1 = 1
b2 =
1 2
b3 = test
</pre></div>
<p>Note in the example the use of the <code>mxDuplicateArray</code> function. This
is needed as the <code>mxArray</code> pointer returned by <code>mxGetCell</code>
might be deallocated. The inverse function to <code>mxGetCell</code>, used for
setting Cell values, is <code>mxSetCell</code> and is defined as
</p>
<div class="example">
<pre class="example">void mxSetCell (mxArray *ptr, int idx, mxArray *val);
</pre></div>
<p>Finally, to create a cell array or matrix, the appropriate functions are
</p>
<div class="example">
<pre class="example">mxArray *mxCreateCellArray (int ndims, const int *dims);
mxArray *mxCreateCellMatrix (int m, int n);
</pre></div>
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