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<a name="ldexp_002c-ldexpf_002d_002d_002dload-exponent"></a>
<h3 class="section">1.33 <code>ldexp</code>, <code>ldexpf</code>&mdash;load exponent</h3>
<a name="index-ldexp"></a>
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<p><strong>Synopsis</strong>
</p><div class="example">
<pre class="example">#include &lt;math.h&gt;
double ldexp(double <var>val</var>, int <var>exp</var>);
float ldexpf(float <var>val</var>, int <var>exp</var>);

</pre></div>
<p><strong>Description</strong><br>
<code>ldexp</code> calculates the value 
<var>val</var> times 2 to the power <var>exp</var>.
<code>ldexpf</code> is identical, save that it takes and returns <code>float</code>
rather than <code>double</code> values.
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<p><strong>Returns</strong><br>
<code>ldexp</code> returns the calculated value.
</p>
<p>Underflow and overflow both set <code>errno</code> to <code>ERANGE</code>.
On underflow, <code>ldexp</code> and <code>ldexpf</code> return 0.0.
On overflow, <code>ldexp</code> returns plus or minus <code>HUGE_VAL</code>.
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<p><strong>Portability</strong><br>
<code>ldexp</code> is ANSI. <code>ldexpf</code> is an extension.
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