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<h3 class="section">8.20 <code>ASSOCIATED</code> — Status of a pointer or pointer/target pair</h3>
<p><a name="index-ASSOCIATED-414"></a><a name="index-pointer_002c-status-415"></a><a name="index-association-status-416"></a>
<dl>
<dt><em>Description</em>:<dd><code>ASSOCIATED(POINTER [, TARGET])</code> determines the status of the pointer
<var>POINTER</var> or if <var>POINTER</var> is associated with the target <var>TARGET</var>.
<br><dt><em>Standard</em>:<dd>Fortran 95 and later
<br><dt><em>Class</em>:<dd>Inquiry function
<br><dt><em>Syntax</em>:<dd><code>RESULT = ASSOCIATED(POINTER [, TARGET])</code>
<br><dt><em>Arguments</em>:<dd>
<p><table summary=""><tr align="left"><td valign="top" width="15%"><var>POINTER</var> </td><td valign="top" width="70%"><var>POINTER</var> shall have the <code>POINTER</code> attribute
and it can be of any type.
<br></td></tr><tr align="left"><td valign="top" width="15%"><var>TARGET</var> </td><td valign="top" width="70%">(Optional) <var>TARGET</var> shall be a pointer or
a target. It must have the same type, kind type parameter, and
array rank as <var>POINTER</var>.
<br></td></tr></table>
The association status of neither <var>POINTER</var> nor <var>TARGET</var> shall be
undefined.
<br><dt><em>Return value</em>:<dd><code>ASSOCIATED(POINTER)</code> returns a scalar value of type <code>LOGICAL(4)</code>.
There are several cases:
<dl>
<dt>(A) When the optional <var>TARGET</var> is not present then<dd><code>ASSOCIATED(POINTER)</code> is true if <var>POINTER</var> is associated with a target; otherwise, it returns false.
<br><dt>(B) If <var>TARGET</var> is present and a scalar target, the result is true if<dd><var>TARGET</var> is not a zero-sized storage sequence and the target associated with <var>POINTER</var> occupies the same storage units. If <var>POINTER</var> is
disassociated, the result is false.
<br><dt>(C) If <var>TARGET</var> is present and an array target, the result is true if<dd><var>TARGET</var> and <var>POINTER</var> have the same shape, are not zero-sized arrays,
are arrays whose elements are not zero-sized storage sequences, and
<var>TARGET</var> and <var>POINTER</var> occupy the same storage units in array element
order.
As in case(B), the result is false, if <var>POINTER</var> is disassociated.
<br><dt>(D) If <var>TARGET</var> is present and an scalar pointer, the result is true<dd>if <var>TARGET</var> is associated with <var>POINTER</var>, the target associated with
<var>TARGET</var> are not zero-sized storage sequences and occupy the same storage
units.
The result is false, if either <var>TARGET</var> or <var>POINTER</var> is disassociated.
<br><dt>(E) If <var>TARGET</var> is present and an array pointer, the result is true if<dd>target associated with <var>POINTER</var> and the target associated with <var>TARGET</var>
have the same shape, are not zero-sized arrays, are arrays whose elements are
not zero-sized storage sequences, and <var>TARGET</var> and <var>POINTER</var> occupy
the same storage units in array element order.
The result is false, if either <var>TARGET</var> or <var>POINTER</var> is disassociated.
</dl>
<br><dt><em>Example</em>:<dd>
<pre class="smallexample"> program test_associated
implicit none
real, target :: tgt(2) = (/1., 2./)
real, pointer :: ptr(:)
ptr => tgt
if (associated(ptr) .eqv. .false.) call abort
if (associated(ptr,tgt) .eqv. .false.) call abort
end program test_associated
</pre>
<br><dt><em>See also</em>:<dd><a href="NULL.html#NULL">NULL</a>
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