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

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Next: <a href="ACCESS.html#ACCESS" accesskey="n" rel="next">ACCESS</a>, Previous: <a href="ABORT.html#ABORT" accesskey="p" rel="prev">ABORT</a>, Up: <a href="Intrinsic-Procedures.html#Intrinsic-Procedures" accesskey="u" rel="up">Intrinsic Procedures</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p>
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<a name="ABS-_002d_002d_002d-Absolute-value"></a>
<h3 class="section">9.3 <code>ABS</code> &mdash; Absolute value</h3>
<a name="index-ABS"></a>
<a name="index-CABS"></a>
<a name="index-DABS"></a>
<a name="index-IABS"></a>
<a name="index-ZABS"></a>
<a name="index-CDABS"></a>
<a name="index-BABS"></a>
<a name="index-IIABS"></a>
<a name="index-JIABS"></a>
<a name="index-KIABS"></a>
<a name="index-absolute-value"></a>

<dl compact="compact">
<dt><em>Description</em>:</dt>
<dd><p><code>ABS(A)</code> computes the absolute value of <code>A</code>.
</p>
</dd>
<dt><em>Standard</em>:</dt>
<dd><p>Fortran 77 and later, has overloads that are GNU extensions
</p>
</dd>
<dt><em>Class</em>:</dt>
<dd><p>Elemental function
</p>
</dd>
<dt><em>Syntax</em>:</dt>
<dd><p><code>RESULT = ABS(A)</code>
</p>
</dd>
<dt><em>Arguments</em>:</dt>
<dd><table>
<tr><td width="15%"><var>A</var></td><td width="70%">The type of the argument shall be an <code>INTEGER</code>,
<code>REAL</code>, or <code>COMPLEX</code>.</td></tr>
</table>

</dd>
<dt><em>Return value</em>:</dt>
<dd><p>The return value is of the same type and
kind as the argument except the return value is <code>REAL</code> for a
<code>COMPLEX</code> argument.
</p>
</dd>
<dt><em>Example</em>:</dt>
<dd><div class="smallexample">
<pre class="smallexample">program test_abs
  integer :: i = -1
  real :: x = -1.e0
  complex :: z = (-1.e0,0.e0)
  i = abs(i)
  x = abs(x)
  x = abs(z)
end program test_abs
</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>ABS(A)</code></td><td width="20%"><code>REAL(4) A</code></td><td width="20%"><code>REAL(4)</code></td><td width="25%">Fortran 77 and later</td></tr>
<tr><td width="20%"><code>CABS(A)</code></td><td width="20%"><code>COMPLEX(4) A</code></td><td width="20%"><code>REAL(4)</code></td><td width="25%">Fortran 77 and later</td></tr>
<tr><td width="20%"><code>DABS(A)</code></td><td width="20%"><code>REAL(8) A</code></td><td width="20%"><code>REAL(8)</code></td><td width="25%">Fortran 77 and later</td></tr>
<tr><td width="20%"><code>IABS(A)</code></td><td width="20%"><code>INTEGER(4) A</code></td><td width="20%"><code>INTEGER(4)</code></td><td width="25%">Fortran 77 and later</td></tr>
<tr><td width="20%"><code>BABS(A)</code></td><td width="20%"><code>INTEGER(1) A</code></td><td width="20%"><code>INTEGER(1)</code></td><td width="25%">GNU extension</td></tr>
<tr><td width="20%"><code>IIABS(A)</code></td><td width="20%"><code>INTEGER(2) A</code></td><td width="20%"><code>INTEGER(2)</code></td><td width="25%">GNU extension</td></tr>
<tr><td width="20%"><code>JIABS(A)</code></td><td width="20%"><code>INTEGER(4) A</code></td><td width="20%"><code>INTEGER(4)</code></td><td width="25%">GNU extension</td></tr>
<tr><td width="20%"><code>KIABS(A)</code></td><td width="20%"><code>INTEGER(8) A</code></td><td width="20%"><code>INTEGER(8)</code></td><td width="25%">GNU extension</td></tr>
<tr><td width="20%"><code>ZABS(A)</code></td><td width="20%"><code>COMPLEX(8) A</code></td><td width="20%"><code>COMPLEX(8)</code></td><td width="25%">GNU extension</td></tr>
<tr><td width="20%"><code>CDABS(A)</code></td><td width="20%"><code>COMPLEX(8) A</code></td><td width="20%"><code>COMPLEX(8)</code></td><td width="25%">GNU extension</td></tr>
</table>
</dd>
</dl>


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