23 lines
3.2 KiB
HTML
23 lines
3.2 KiB
HTML
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>Chapter 26. Numerics</title><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><meta name="keywords" content="ISO C++, library" /><meta name="keywords" content="ISO C++, runtime, library" /><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><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.
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Extensions
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</th><td width="20%" align="right"> <a accesskey="n" href="ext_iterators.html">Next</a></td></tr></table><hr /></div><div class="chapter"><div class="titlepage"><div><div><h2 class="title"><a id="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>,
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are extended with the following functions:
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</p><pre class="programlisting">
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power (x, n);
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power (x, n, monoid_operation);</pre><p>Returns, in FORTRAN syntax, "<code class="code">x ** n</code>" where
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<code class="code">n >= 0</code>. In the
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case of <code class="code">n == 0</code>, returns the identity element for the
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monoid operation. The two-argument signature uses multiplication (for
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a true "power" implementation), but addition is supported as well.
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The operation functor must be associative.
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</p><p>The <code class="code">iota</code> function wins the award for Extension With the
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Coolest Name (the name comes from Ken Iverson's APL language.) As
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described in the <a class="link" href="http://www.sgi.com/tech/stl/iota.html" target="_top">SGI
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documentation</a>, it "assigns sequentially increasing values to a range.
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That is, it assigns <code class="code">value</code> to <code class="code">*first</code>,
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<code class="code">value + 1</code> to<code class="code"> *(first + 1)</code> and so on."
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</p><pre class="programlisting">
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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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</p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="ext_algorithms.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="extensions.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="ext_iterators.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Chapter 25. Algorithms </td><td width="20%" align="center"><a accesskey="h" href="../index.html">Home</a></td><td width="40%" align="right" valign="top"> Chapter 27. Iterators</td></tr></table></div></body></html> |