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

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<hr>
<a name="REAL-_002d_002d_002d-Convert-to-real-type"></a>
<h3 class="section">9.226 <code>REAL</code> &mdash; Convert to real type</h3>
<a name="index-REAL"></a>
<a name="index-REALPART"></a>
<a name="index-FLOAT"></a>
<a name="index-DFLOAT"></a>
<a name="index-FLOATI"></a>
<a name="index-FLOATJ"></a>
<a name="index-FLOATK"></a>
<a name="index-SNGL"></a>
<a name="index-conversion_002c-to-real-1"></a>
<a name="index-complex-numbers_002c-real-part-1"></a>

<dl compact="compact">
<dt><em>Description</em>:</dt>
<dd><p><code>REAL(A [, KIND])</code> converts its argument <var>A</var> to a real type.  The
<code>REALPART</code> function is provided for compatibility with <code>g77</code>,
and its use is strongly discouraged.
</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><table>
<tr><td width="80%"><code>RESULT = REAL(A [, KIND])</code></td></tr>
<tr><td width="80%"><code>RESULT = REALPART(Z)</code></td></tr>
</table>

</dd>
<dt><em>Arguments</em>:</dt>
<dd><table>
<tr><td width="15%"><var>A</var></td><td width="70%">Shall be <code>INTEGER</code>, <code>REAL</code>, or
<code>COMPLEX</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>These functions return a <code>REAL</code> variable or array under
the following rules: 
</p>
<dl compact="compact">
<dt>(A)</dt>
<dd><p><code>REAL(A)</code> is converted to a default real type if <var>A</var> is an 
integer or real variable.
</p></dd>
<dt>(B)</dt>
<dd><p><code>REAL(A)</code> is converted to a real type with the kind type parameter
of <var>A</var> if <var>A</var> is a complex variable.
</p></dd>
<dt>(C)</dt>
<dd><p><code>REAL(A, KIND)</code> is converted to a real type with kind type
parameter <var>KIND</var> if <var>A</var> is a complex, integer, or real
variable.
</p></dd>
</dl>

</dd>
<dt><em>Example</em>:</dt>
<dd><div class="smallexample">
<pre class="smallexample">program test_real
  complex :: x = (1.0, 2.0)
  print *, real(x), real(x,8), realpart(x)
end program test_real
</pre></div>

</dd>
<dt><em>Specific names</em>:</dt>
<dd><table>
<tr><td width="20%">Name</td><td width="20%">Argument</td><td width="20%">Return type</td><td width="25%">Standard</td></tr>
<tr><td width="20%"><code>FLOAT(A)</code></td><td width="20%"><code>INTEGER(4)</code></td><td width="20%"><code>REAL(4)</code></td><td width="25%">Fortran 77 and later</td></tr>
<tr><td width="20%"><code>DFLOAT(A)</code></td><td width="20%"><code>INTEGER(4)</code></td><td width="20%"><code>REAL(8)</code></td><td width="25%">GNU extension</td></tr>
<tr><td width="20%"><code>FLOATI(A)</code></td><td width="20%"><code>INTEGER(2)</code></td><td width="20%"><code>REAL(4)</code></td><td width="25%">GNU extension</td></tr>
<tr><td width="20%"><code>FLOATJ(A)</code></td><td width="20%"><code>INTEGER(4)</code></td><td width="20%"><code>REAL(4)</code></td><td width="25%">GNU extension</td></tr>
<tr><td width="20%"><code>FLOATK(A)</code></td><td width="20%"><code>INTEGER(8)</code></td><td width="20%"><code>REAL(4)</code></td><td width="25%">GNU extension</td></tr>
<tr><td width="20%"><code>SNGL(A)</code></td><td width="20%"><code>INTEGER(8)</code></td><td width="20%"><code>REAL(4)</code></td><td width="25%">Fortran 77 and later</td></tr>
</table>


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


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