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<h3 class="section">11.5 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:

<pre class="example">     return
</pre>
   <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>Here is an example of a function that checks to see if any elements of a
vector are nonzero.

<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>
   <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.

<div class="defun">
&mdash; Keyword: <b>return</b><var><a name="index-return-610"></a></var><br>
<blockquote><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></blockquote></div>

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