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<a name="PRESENT-_002d_002d_002d-Determine-whether-an-optional-dummy-argument-is-specified"></a>
<h3 class="section">9.217 <code>PRESENT</code> &mdash; Determine whether an optional dummy argument is specified</h3>
<a name="index-PRESENT"></a>

<dl compact="compact">
<dt><em>Description</em>:</dt>
<dd><p>Determines whether an optional dummy argument is present.
</p>
</dd>
<dt><em>Standard</em>:</dt>
<dd><p>Fortran 95 and later
</p>
</dd>
<dt><em>Class</em>:</dt>
<dd><p>Inquiry function
</p>
</dd>
<dt><em>Syntax</em>:</dt>
<dd><p><code>RESULT = PRESENT(A)</code>
</p>
</dd>
<dt><em>Arguments</em>:</dt>
<dd><table>
<tr><td width="15%"><var>A</var></td><td width="70%">May be of any type and may be a pointer, scalar or array
value, or a dummy procedure. It shall be the name of an optional dummy argument
accessible within the current subroutine or function.</td></tr>
</table>

</dd>
<dt><em>Return value</em>:</dt>
<dd><p>Returns either <code>TRUE</code> if the optional argument <var>A</var> is present, or
<code>FALSE</code> otherwise.
</p>
</dd>
<dt><em>Example</em>:</dt>
<dd><div class="smallexample">
<pre class="smallexample">PROGRAM test_present
  WRITE(*,*) f(), f(42)      ! &quot;F T&quot;
CONTAINS
  LOGICAL FUNCTION f(x)
    INTEGER, INTENT(IN), OPTIONAL :: x
    f = PRESENT(x)
  END FUNCTION
END PROGRAM
</pre></div>
</dd>
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