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

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<hr>
<a name="CMPLX-_002d_002d_002d-Complex-conversion-function"></a>
<h3 class="section">9.62 <code>CMPLX</code> &mdash; Complex conversion function</h3>
<a name="index-CMPLX"></a>
<a name="index-complex-numbers_002c-conversion-to"></a>
<a name="index-conversion_002c-to-complex"></a>

<dl compact="compact">
<dt><em>Description</em>:</dt>
<dd><p><code>CMPLX(X [, Y [, KIND]])</code> returns a complex number where <var>X</var> is converted to
the real component.  If <var>Y</var> is present it is converted to the imaginary
component.  If <var>Y</var> is not present then the imaginary component is set to
0.0.  If <var>X</var> is complex then <var>Y</var> must not be present.
</p>
</dd>
<dt><em>Standard</em>:</dt>
<dd><p>Fortran 77 and later
</p>
</dd>
<dt><em>Class</em>:</dt>
<dd><p>Elemental function
</p>
</dd>
<dt><em>Syntax</em>:</dt>
<dd><p><code>RESULT = CMPLX(X [, Y [, KIND]])</code>
</p>
</dd>
<dt><em>Arguments</em>:</dt>
<dd><table>
<tr><td width="15%"><var>X</var></td><td width="70%">The type may be <code>INTEGER</code>, <code>REAL</code>,
or <code>COMPLEX</code>.</td></tr>
<tr><td width="15%"><var>Y</var></td><td width="70%">(Optional; only allowed if <var>X</var> is not
<code>COMPLEX</code>.)  May be <code>INTEGER</code> or <code>REAL</code>.</td></tr>
<tr><td width="15%"><var>KIND</var></td><td width="70%">(Optional) An <code>INTEGER</code> initialization
expression indicating the kind parameter of the result.</td></tr>
</table>

</dd>
<dt><em>Return value</em>:</dt>
<dd><p>The return value is of <code>COMPLEX</code> type, with a kind equal to
<var>KIND</var> if it is specified.  If <var>KIND</var> is not specified, the
result is of the default <code>COMPLEX</code> kind, regardless of the kinds of
<var>X</var> and <var>Y</var>. 
</p>
</dd>
<dt><em>Example</em>:</dt>
<dd><div class="smallexample">
<pre class="smallexample">program test_cmplx
    integer :: i = 42
    real :: x = 3.14
    complex :: z
    z = cmplx(i, x)
    print *, z, cmplx(x)
end program test_cmplx
</pre></div>

</dd>
<dt><em>See also</em>:</dt>
<dd><p><a href="COMPLEX.html#COMPLEX">COMPLEX</a>
</p></dd>
</dl>


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