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<a name="Returning-from-a-Function"></a>
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Next: <a href="Default-Arguments.html#Default-Arguments" accesskey="n" rel="next">Default Arguments</a>, Previous: <a href="Variable_002dlength-Return-Lists.html#Variable_002dlength-Return-Lists" accesskey="p" rel="prev">Variable-length Return Lists</a>, Up: <a href="Functions-and-Scripts.html#Functions-and-Scripts" accesskey="u" rel="up">Functions and Scripts</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="Returning-from-a-Function-1"></a>
<h3 class="section">11.7 Returning from a Function</h3>
<p>The body of a user-defined function can contain a <code>return</code> statement.
This statement returns control to the rest of the Octave program. It
looks like this:
</p>
<div class="example">
<pre class="example">return
</pre></div>
<p>Unlike the <code>return</code> statement in C, Octave’s <code>return</code>
statement cannot be used to return a value from a function. Instead,
you must assign values to the list of return variables that are part of
the <code>function</code> statement. The <code>return</code> statement simply makes
it easier to exit a function from a deeply nested loop or conditional
statement.
</p>
<p>Here is an example of a function that checks to see if any elements of a
vector are nonzero.
</p>
<div class="example">
<pre class="example">function retval = any_nonzero (v)
retval = 0;
for i = 1:length (v)
if (v (i) != 0)
retval = 1;
return;
endif
endfor
printf ("no nonzero elements found\n");
endfunction
</pre></div>
<p>Note that this function could not have been written using the
<code>break</code> statement to exit the loop once a nonzero value is found
without adding extra logic to avoid printing the message if the vector
does contain a nonzero element.
</p>
<dl>
<dt><a name="index-return"></a>Keyword: <em></em> <strong>return</strong></dt>
<dd><p>When Octave encounters the keyword <code>return</code> inside a function or
script, it returns control to the caller immediately. At the top level,
the return statement is ignored. A <code>return</code> statement is assumed
at the end of every function definition.
</p></dd></dl>
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