1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 2<html> 3<head> 4<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 5<title>Class template base_dimension</title> 6<link rel="stylesheet" href="../../../../doc/src/boostbook.css" type="text/css"> 7<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> 8<link rel="home" href="../../index.html" title="The Boost C++ Libraries BoostBook Documentation Subset"> 9<link rel="up" href="../../boost_units/Reference.html#header.boost.units.base_dimension_hpp" title="Header <boost/units/base_dimension.hpp>"> 10<link rel="prev" href="../../BOOST_UNIT_1_3_44_10_2_2_4.html" title="Macro BOOST_UNITS_DEFINE_CONVERSION_OFFSET"> 11<link rel="next" href="base_unit.html" title="Class template base_unit"> 12</head> 13<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 14<table cellpadding="2" width="100%"><tr> 15<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../boost.png"></td> 16<td align="center"><a href="../../../../index.html">Home</a></td> 17<td align="center"><a href="../../../../libs/libraries.htm">Libraries</a></td> 18<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> 19<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> 20<td align="center"><a href="../../../../more/index.htm">More</a></td> 21</tr></table> 22<hr> 23<div class="spirit-nav"> 24<a accesskey="p" href="../../BOOST_UNIT_1_3_44_10_2_2_4.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../boost_units/Reference.html#header.boost.units.base_dimension_hpp"><img src="../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="base_unit.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a> 25</div> 26<div class="refentry"> 27<a name="boost.units.base_dimension"></a><div class="titlepage"></div> 28<div class="refnamediv"> 29<h2><span class="refentrytitle">Class template base_dimension</span></h2> 30<p>boost::units::base_dimension</p> 31</div> 32<h2 xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv-title">Synopsis</h2> 33<div xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv"><pre class="synopsis"><span class="comment">// In header: <<a class="link" href="../../boost_units/Reference.html#header.boost.units.base_dimension_hpp" title="Header <boost/units/base_dimension.hpp>">boost/units/base_dimension.hpp</a>> 34 35</span><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Derived<span class="special">,</span> <span class="keyword">long</span> N<span class="special">></span> 36<span class="keyword">class</span> <a class="link" href="base_dimension.html" title="Class template base_dimension">base_dimension</a> <span class="special">:</span> <span class="keyword">public</span> <span class="identifier">ordinal</span><span class="special"><</span> <span class="identifier">N</span> <span class="special">></span> <span class="special">{</span> 37<span class="keyword">public</span><span class="special">:</span> 38 <span class="comment">// types</span> 39 <span class="keyword">typedef</span> <span class="emphasis"><em><span class="identifier">unspecified</span></em></span> <a name="boost.units.base_dimension.dimension_type"></a><span class="identifier">dimension_type</span><span class="special">;</span> <span class="comment">// A convenience typedef. Equivalent to boost::units::derived_dimension<Derived,1>::type. </span> 40 <span class="keyword">typedef</span> <span class="identifier">Derived</span> <a name="boost.units.base_dimension.type"></a><span class="identifier">type</span><span class="special">;</span> <span class="comment">// Provided for mpl compatability. </span> 41<span class="special">}</span><span class="special">;</span></pre></div> 42<div class="refsect1"> 43<a name="id-1.3.44.10.2.3.5.4"></a><h2>Description</h2> 44<p>Defines a base dimension. To define a dimension you need to provide the derived class (CRTP) and a unique integer. </p> 45<pre class="programlisting"><span class="keyword">struct</span> <span class="identifier">my_dimension</span> <span class="special">:</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">units</span><span class="special">::</span><span class="identifier">base_dimension</span><span class="special"><</span><span class="identifier">my_dimension</span><span class="special">,</span> <span class="number">1</span><span class="special">></span> <span class="special">{</span><span class="special">}</span><span class="special">;</span> 46</pre> 47<p> It is designed so that you will get an error message if you try to use the same value in multiple definitions. </p> 48</div> 49</div> 50<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 51<td align="left"></td> 52<td align="right"><div class="copyright-footer">Copyright © 2003-2008 Matthias Christian Schabel<br>Copyright © 2007-2010 Steven 53 Watanabe<p> 54 Distributed under the Boost Software License, Version 1.0. (See accompanying 55 file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>) 56 </p> 57</div></td> 58</tr></table> 59<hr> 60<div class="spirit-nav"> 61<a accesskey="p" href="../../BOOST_UNIT_1_3_44_10_2_2_4.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../boost_units/Reference.html#header.boost.units.base_dimension_hpp"><img src="../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="base_unit.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a> 62</div> 63</body> 64</html> 65
