1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>Binding member functions</title> 5<link rel="stylesheet" href="../../../../../../../doc/src/boostbook.css" type="text/css"> 6<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> 7<link rel="home" href="../../index.html" title="Chapter 1. Boost.Numeric.Odeint"> 8<link rel="up" href="../odeint_in_detail.html" title="odeint in detail"> 9<link rel="prev" href="using_boost__range.html" title="Using boost::range"> 10<link rel="next" href="../concepts.html" title="Concepts"> 11</head> 12<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 13<table cellpadding="2" width="100%"><tr> 14<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../logo.jpg"></td> 15<td align="center"><a href="../../../../../../../index.html">Home</a></td> 16<td align="center"><a href="../../../../../../../libs/libraries.htm">Libraries</a></td> 17<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> 18<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> 19<td align="center"><a href="../../../../../../../more/index.htm">More</a></td> 20</tr></table> 21<hr> 22<div class="spirit-nav"> 23<a accesskey="p" href="using_boost__range.html"><img src="../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../odeint_in_detail.html"><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="../concepts.html"><img src="../../../../../../../doc/src/images/next.png" alt="Next"></a> 24</div> 25<div class="section"> 26<div class="titlepage"><div><div><h3 class="title"> 27<a name="boost_numeric_odeint.odeint_in_detail.binding_member_functions"></a><a class="link" href="binding_member_functions.html" title="Binding member functions">Binding 28 member functions</a> 29</h3></div></div></div> 30<div class="toc"><dl class="toc"><dt><span class="section"><a href="binding_member_functions.html#boost_numeric_odeint.odeint_in_detail.binding_member_functions.binding_member_functions_in_c__11">Binding 31 member functions in C++11</a></span></dt></dl></div> 32<p> 33 Binding member functions to a function objects suitable for odeint system 34 function is not easy, at least in C++03. The usual way of using __boost_bind 35 does not work because of the forwarding problem. odeint provides two <code class="computeroutput"><span class="identifier">do_step</span></code> method which only differ in the 36 const specifiers of the arguments and __boost_bind binders only provide the 37 specializations up to two argument which is not enough for odeint. 38 </p> 39<p> 40 But one can easily implement the according binders themself: 41 </p> 42<p> 43</p> 44<pre class="programlisting"><span class="keyword">template</span><span class="special"><</span> <span class="keyword">class</span> <span class="identifier">Obj</span> <span class="special">,</span> <span class="keyword">class</span> <span class="identifier">Mem</span> <span class="special">></span> 45<span class="keyword">class</span> <span class="identifier">ode_wrapper</span> 46<span class="special">{</span> 47 <span class="identifier">Obj</span> <span class="identifier">m_obj</span><span class="special">;</span> 48 <span class="identifier">Mem</span> <span class="identifier">m_mem</span><span class="special">;</span> 49 50<span class="keyword">public</span><span class="special">:</span> 51 52 <span class="identifier">ode_wrapper</span><span class="special">(</span> <span class="identifier">Obj</span> <span class="identifier">obj</span> <span class="special">,</span> <span class="identifier">Mem</span> <span class="identifier">mem</span> <span class="special">)</span> <span class="special">:</span> <span class="identifier">m_obj</span><span class="special">(</span> <span class="identifier">obj</span> <span class="special">)</span> <span class="special">,</span> <span class="identifier">m_mem</span><span class="special">(</span> <span class="identifier">mem</span> <span class="special">)</span> <span class="special">{</span> <span class="special">}</span> 53 54 <span class="keyword">template</span><span class="special"><</span> <span class="keyword">class</span> <span class="identifier">State</span> <span class="special">,</span> <span class="keyword">class</span> <span class="identifier">Deriv</span> <span class="special">,</span> <span class="keyword">class</span> <span class="identifier">Time</span> <span class="special">></span> 55 <span class="keyword">void</span> <span class="keyword">operator</span><span class="special">()(</span> <span class="keyword">const</span> <span class="identifier">State</span> <span class="special">&</span><span class="identifier">x</span> <span class="special">,</span> <span class="identifier">Deriv</span> <span class="special">&</span><span class="identifier">dxdt</span> <span class="special">,</span> <span class="identifier">Time</span> <span class="identifier">t</span> <span class="special">)</span> 56 <span class="special">{</span> 57 <span class="special">(</span><span class="identifier">m_obj</span><span class="special">.*</span><span class="identifier">m_mem</span><span class="special">)(</span> <span class="identifier">x</span> <span class="special">,</span> <span class="identifier">dxdt</span> <span class="special">,</span> <span class="identifier">t</span> <span class="special">);</span> 58 <span class="special">}</span> 59<span class="special">};</span> 60 61<span class="keyword">template</span><span class="special"><</span> <span class="keyword">class</span> <span class="identifier">Obj</span> <span class="special">,</span> <span class="keyword">class</span> <span class="identifier">Mem</span> <span class="special">></span> 62<span class="identifier">ode_wrapper</span><span class="special"><</span> <span class="identifier">Obj</span> <span class="special">,</span> <span class="identifier">Mem</span> <span class="special">></span> <span class="identifier">make_ode_wrapper</span><span class="special">(</span> <span class="identifier">Obj</span> <span class="identifier">obj</span> <span class="special">,</span> <span class="identifier">Mem</span> <span class="identifier">mem</span> <span class="special">)</span> 63<span class="special">{</span> 64 <span class="keyword">return</span> <span class="identifier">ode_wrapper</span><span class="special"><</span> <span class="identifier">Obj</span> <span class="special">,</span> <span class="identifier">Mem</span> <span class="special">>(</span> <span class="identifier">obj</span> <span class="special">,</span> <span class="identifier">mem</span> <span class="special">);</span> 65<span class="special">}</span> 66</pre> 67<p> 68 </p> 69<p> 70 One can use this binder as follows 71 </p> 72<p> 73</p> 74<pre class="programlisting"><span class="keyword">struct</span> <span class="identifier">lorenz</span> 75<span class="special">{</span> 76 <span class="keyword">void</span> <span class="identifier">ode</span><span class="special">(</span> <span class="keyword">const</span> <span class="identifier">state_type</span> <span class="special">&</span><span class="identifier">x</span> <span class="special">,</span> <span class="identifier">state_type</span> <span class="special">&</span><span class="identifier">dxdt</span> <span class="special">,</span> <span class="keyword">double</span> <span class="identifier">t</span> <span class="special">)</span> <span class="keyword">const</span> 77 <span class="special">{</span> 78 <span class="identifier">dxdt</span><span class="special">[</span><span class="number">0</span><span class="special">]</span> <span class="special">=</span> <span class="number">10.0</span> <span class="special">*</span> <span class="special">(</span> <span class="identifier">x</span><span class="special">[</span><span class="number">1</span><span class="special">]</span> <span class="special">-</span> <span class="identifier">x</span><span class="special">[</span><span class="number">0</span><span class="special">]</span> <span class="special">);</span> 79 <span class="identifier">dxdt</span><span class="special">[</span><span class="number">1</span><span class="special">]</span> <span class="special">=</span> <span class="number">28.0</span> <span class="special">*</span> <span class="identifier">x</span><span class="special">[</span><span class="number">0</span><span class="special">]</span> <span class="special">-</span> <span class="identifier">x</span><span class="special">[</span><span class="number">1</span><span class="special">]</span> <span class="special">-</span> <span class="identifier">x</span><span class="special">[</span><span class="number">0</span><span class="special">]</span> <span class="special">*</span> <span class="identifier">x</span><span class="special">[</span><span class="number">2</span><span class="special">];</span> 80 <span class="identifier">dxdt</span><span class="special">[</span><span class="number">2</span><span class="special">]</span> <span class="special">=</span> <span class="special">-</span><span class="number">8.0</span> <span class="special">/</span> <span class="number">3.0</span> <span class="special">*</span> <span class="identifier">x</span><span class="special">[</span><span class="number">2</span><span class="special">]</span> <span class="special">+</span> <span class="identifier">x</span><span class="special">[</span><span class="number">0</span><span class="special">]</span> <span class="special">*</span> <span class="identifier">x</span><span class="special">[</span><span class="number">1</span><span class="special">];</span> 81 <span class="special">}</span> 82<span class="special">};</span> 83 84<span class="keyword">int</span> <span class="identifier">main</span><span class="special">(</span> <span class="keyword">int</span> <span class="identifier">argc</span> <span class="special">,</span> <span class="keyword">char</span> <span class="special">*</span><span class="identifier">argv</span><span class="special">[]</span> <span class="special">)</span> 85<span class="special">{</span> 86 <span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">numeric</span><span class="special">::</span><span class="identifier">odeint</span><span class="special">;</span> 87 <span class="identifier">state_type</span> <span class="identifier">x</span> <span class="special">=</span> <span class="special">{{</span> <span class="number">10.0</span> <span class="special">,</span> <span class="number">10.0</span> <span class="special">,</span> <span class="number">10.0</span> <span class="special">}};</span> 88 <span class="identifier">integrate_const</span><span class="special">(</span> <span class="identifier">runge_kutta4</span><span class="special"><</span> <span class="identifier">state_type</span> <span class="special">>()</span> <span class="special">,</span> <span class="identifier">make_ode_wrapper</span><span class="special">(</span> <span class="identifier">lorenz</span><span class="special">()</span> <span class="special">,</span> <span class="special">&</span><span class="identifier">lorenz</span><span class="special">::</span><span class="identifier">ode</span> <span class="special">)</span> <span class="special">,</span> 89 <span class="identifier">x</span> <span class="special">,</span> <span class="number">0.0</span> <span class="special">,</span> <span class="number">10.0</span> <span class="special">,</span> <span class="number">0.01</span> <span class="special">);</span> 90 <span class="keyword">return</span> <span class="number">0</span><span class="special">;</span> 91<span class="special">}</span> 92</pre> 93<p> 94 </p> 95<div class="section"> 96<div class="titlepage"><div><div><h4 class="title"> 97<a name="boost_numeric_odeint.odeint_in_detail.binding_member_functions.binding_member_functions_in_c__11"></a><a class="link" href="binding_member_functions.html#boost_numeric_odeint.odeint_in_detail.binding_member_functions.binding_member_functions_in_c__11" title="Binding member functions in C++11">Binding 98 member functions in C++11</a> 99</h4></div></div></div> 100<p> 101 In C++11 one can use <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">bind</span></code> 102 and one does not need to implement the bind themself: 103 </p> 104<p> 105</p> 106<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">pl</span> <span class="special">=</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">placeholders</span><span class="special">;</span> 107 108<span class="identifier">state_type</span> <span class="identifier">x</span> <span class="special">=</span> <span class="special">{{</span> <span class="number">10.0</span> <span class="special">,</span> <span class="number">10.0</span> <span class="special">,</span> <span class="number">10.0</span> <span class="special">}};</span> 109<span class="identifier">integrate_const</span><span class="special">(</span> <span class="identifier">runge_kutta4</span><span class="special"><</span> <span class="identifier">state_type</span> <span class="special">>()</span> <span class="special">,</span> 110 <span class="identifier">std</span><span class="special">::</span><span class="identifier">bind</span><span class="special">(</span> <span class="special">&</span><span class="identifier">lorenz</span><span class="special">::</span><span class="identifier">ode</span> <span class="special">,</span> <span class="identifier">lorenz</span><span class="special">()</span> <span class="special">,</span> <span class="identifier">pl</span><span class="special">::</span><span class="identifier">_1</span> <span class="special">,</span> <span class="identifier">pl</span><span class="special">::</span><span class="identifier">_2</span> <span class="special">,</span> <span class="identifier">pl</span><span class="special">::</span><span class="identifier">_3</span> <span class="special">)</span> <span class="special">,</span> 111 <span class="identifier">x</span> <span class="special">,</span> <span class="number">0.0</span> <span class="special">,</span> <span class="number">10.0</span> <span class="special">,</span> <span class="number">0.01</span> <span class="special">);</span> 112</pre> 113<p> 114 </p> 115</div> 116</div> 117<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 118<td align="left"></td> 119<td align="right"><div class="copyright-footer">Copyright © 2009-2015 Karsten Ahnert and Mario Mulansky<p> 120 Distributed under the Boost Software License, Version 1.0. (See accompanying 121 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>) 122 </p> 123</div></td> 124</tr></table> 125<hr> 126<div class="spirit-nav"> 127<a accesskey="p" href="using_boost__range.html"><img src="../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../odeint_in_detail.html"><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="../concepts.html"><img src="../../../../../../../doc/src/images/next.png" alt="Next"></a> 128</div> 129</body> 130</html> 131
