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<title>The GNU Fortran Compiler: ALLOCATED</title>

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<a name="ALLOCATED-_002d_002d_002d-Status-of-an-allocatable-entity"></a>
<h3 class="section">9.15 <code>ALLOCATED</code> &mdash; Status of an allocatable entity</h3>
<a name="index-ALLOCATED"></a>
<a name="index-allocation_002c-status"></a>

<dl compact="compact">
<dt><em>Description</em>:</dt>
<dd><p><code>ALLOCATED(ARRAY)</code> and <code>ALLOCATED(SCALAR)</code> check the allocation
status of <var>ARRAY</var> and <var>SCALAR</var>, respectively.
</p>
</dd>
<dt><em>Standard</em>:</dt>
<dd><p>Fortran 95 and later.  Note, the <code>SCALAR=</code> keyword and allocatable
scalar entities are available in Fortran 2003 and later.
</p>
</dd>
<dt><em>Class</em>:</dt>
<dd><p>Inquiry function
</p>
</dd>
<dt><em>Syntax</em>:</dt>
<dd><table>
<tr><td width="80%"><code>RESULT = ALLOCATED(ARRAY)</code></td></tr>
<tr><td width="80%"><code>RESULT = ALLOCATED(SCALAR)</code></td></tr>
</table>

</dd>
<dt><em>Arguments</em>:</dt>
<dd><table>
<tr><td width="15%"><var>ARRAY</var></td><td width="70%">The argument shall be an <code>ALLOCATABLE</code> array.</td></tr>
<tr><td width="15%"><var>SCALAR</var></td><td width="70%">The argument shall be an <code>ALLOCATABLE</code> scalar.</td></tr>
</table>

</dd>
<dt><em>Return value</em>:</dt>
<dd><p>The return value is a scalar <code>LOGICAL</code> with the default logical
kind type parameter.  If the argument is allocated, then the result is
<code>.TRUE.</code>; otherwise, it returns <code>.FALSE.</code> 
</p>
</dd>
<dt><em>Example</em>:</dt>
<dd><div class="smallexample">
<pre class="smallexample">program test_allocated
  integer :: i = 4
  real(4), allocatable :: x(:)
  if (.not. allocated(x)) allocate(x(i))
end program test_allocated
</pre></div>
</dd>
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