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Numerics
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</p><p>There are four generalized functions in the &lt;numeric&gt; header
that follow the same conventions as those in &lt;algorithm&gt;. Each
of them is overloaded: one signature for common default operations,
and a second for fully general operations. Their names are
self-explanatory to anyone who works with numerics on a regular basis:
</p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p><code class="code">accumulate</code></p></li><li class="listitem"><p><code class="code">inner_product</code></p></li><li class="listitem"><p><code class="code">partial_sum</code></p></li><li class="listitem"><p><code class="code">adjacent_difference</code></p></li></ul></div><p>Here is a simple example of the two forms of <code class="code">accumulate</code>.
</p><pre class="programlisting">
int ar[50];
int someval = somefunction();
// ...initialize members of ar to something...
int sum = std::accumulate(ar,ar+50,0);
int sum_stuff = std::accumulate(ar,ar+50,someval);
int product = std::accumulate(ar,ar+50,1,std::multiplies&lt;int&gt;());
</pre><p>The first call adds all the members of the array, using zero as an
initial value for <code class="code">sum</code>. The second does the same, but uses
<code class="code">someval</code> as the starting value (thus, <code class="code">sum_stuff == sum +
someval</code>). The final call uses the second of the two signatures,
and multiplies all the members of the array; here we must obviously
use 1 as a starting value instead of 0.
</p><p>The other three functions have similar dual-signature forms.
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