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  11     "><link rel="home" href="../index.html" title="The GNU C++ Library"><link rel="up" href="extensions.html" title="Part III.  Extensions"><link rel="prev" href="ext_algorithms.html" title="Chapter 25. Algorithms"><link rel="next" href="ext_iterators.html" title="Chapter 27. Iterators"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Chapter 26. Numerics</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="ext_algorithms.html">Prev</a> </td><th width="60%" align="center">Part III.
  12   Extensions
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  14 </th><td width="20%" align="right"> <a accesskey="n" href="ext_iterators.html">Next</a></td></tr></table><hr></div><div class="chapter" title="Chapter 26. Numerics"><div class="titlepage"><div><div><h2 class="title"><a name="manual.ext.numerics"></a>Chapter 26. Numerics</h2></div></div></div><p>26.4, the generalized numeric operations such as <code class="code">accumulate</code>,
  15    are extended with the following functions:
  16 </p><pre class="programlisting">
  17    power (x, n);
  18    power (x, n, monoid_operation);</pre><p>Returns, in FORTRAN syntax, "<code class="code">x ** n</code>" where
  19    <code class="code">n &gt;= 0</code>.  In the
  20    case of <code class="code">n == 0</code>, returns the identity element for the
  21    monoid operation.  The two-argument signature uses multiplication (for
  22    a true "power" implementation), but addition is supported as well.
  23    The operation functor must be associative.
  24 </p><p>The <code class="code">iota</code> function wins the award for Extension With the
  25    Coolest Name (the name comes from Ken Iverson's APL language.)  As
  26    described in the <a class="link" href="http://www.sgi.com/tech/stl/iota.html" target="_top">SGI
  27    documentation</a>, it "assigns sequentially increasing values to a range.
  28    That is, it assigns <code class="code">value</code> to <code class="code">*first</code>,
  29    <code class="code">value + 1</code> to<code class="code"> *(first + 1)</code> and so on."
  30 </p><pre class="programlisting">
  31    void iota(_ForwardIter first, _ForwardIter last, _Tp value);</pre><p>The <code class="code">iota</code> function is included in the ISO C++ 2011 standard.
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