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  15   </p><p>There are four generalized functions in the &lt;numeric&gt; header
  16       that follow the same conventions as those in &lt;algorithm&gt;.  Each
  17       of them is overloaded:  one signature for common default operations,
  18       and a second for fully general operations.  Their names are
  19       self-explanatory to anyone who works with numerics on a regular basis:
  20    </p><div class="itemizedlist"><ul class="itemizedlist" 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">chapterial_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>.
  21    </p><pre class="programlisting">
  22    int   ar[50];
  23    int   someval = somefunction();
  24
  25    // ...initialize members of ar to something...
  26
  27    int  sum       = std::accumulate(ar,ar+50,0);
  28    int  sum_stuff = std::accumulate(ar,ar+50,someval);
  29    int  product   = std::accumulate(ar,ar+50,1,std::multiplies&lt;int&gt;());
  30    </pre><p>The first call adds all the members of the array, using zero as an
  31       initial value for <code class="code">sum</code>.  The second does the same, but uses
  32       <code class="code">someval</code> as the starting value (thus, <code class="code">sum_stuff == sum +
  33       someval</code>).  The final call uses the second of the two signatures,
  34       and multiplies all the members of the array; here we must obviously
  35       use 1 as a starting value instead of 0.
  36    </p><p>The other three functions have similar dual-signature forms.
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