1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>Class template explicit_error_generic_rk</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="../../../header/boost/numeric/odeint/stepper/explicit_error_generic_rk_hpp.html" title="Header <boost/numeric/odeint/stepper/explicit_error_generic_rk.hpp>"> 9<link rel="prev" href="../../../header/boost/numeric/odeint/stepper/explicit_error_generic_rk_hpp.html" title="Header <boost/numeric/odeint/stepper/explicit_error_generic_rk.hpp>"> 10<link rel="next" href="../../../header/boost/numeric/odeint/stepper/explicit_generic_rk_hpp.html" title="Header <boost/numeric/odeint/stepper/explicit_generic_rk.hpp>"> 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="../../../header/boost/numeric/odeint/stepper/explicit_error_generic_rk_hpp.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../../header/boost/numeric/odeint/stepper/explicit_error_generic_rk_hpp.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="../../../header/boost/numeric/odeint/stepper/explicit_generic_rk_hpp.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a> 24</div> 25<div class="refentry"> 26<a name="boost.numeric.odeint.explicit_error_generic_rk"></a><div class="titlepage"></div> 27<div class="refnamediv"> 28<h2><span class="refentrytitle">Class template explicit_error_generic_rk</span></h2> 29<p>boost::numeric::odeint::explicit_error_generic_rk — A generic implementation of explicit Runge-Kutta algorithms with error estimation. This class is as a base class for all explicit Runge-Kutta steppers with error estimation. </p> 30</div> 31<h2 xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv-title">Synopsis</h2> 32<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="../../../header/boost/numeric/odeint/stepper/explicit_error_generic_rk_hpp.html" title="Header <boost/numeric/odeint/stepper/explicit_error_generic_rk.hpp>">boost/numeric/odeint/stepper/explicit_error_generic_rk.hpp</a>> 33 34</span><span class="keyword">template</span><span class="special"><</span><span class="identifier">size_t</span> StageCount<span class="special">,</span> <span class="identifier">size_t</span> Order<span class="special">,</span> <span class="identifier">size_t</span> StepperOrder<span class="special">,</span> 35 <span class="identifier">size_t</span> ErrorOrder<span class="special">,</span> <span class="keyword">typename</span> State<span class="special">,</span> <span class="keyword">typename</span> Value <span class="special">=</span> <span class="keyword">double</span><span class="special">,</span> 36 <span class="keyword">typename</span> Deriv <span class="special">=</span> <span class="identifier">State</span><span class="special">,</span> <span class="keyword">typename</span> Time <span class="special">=</span> <span class="identifier">Value</span><span class="special">,</span> 37 <span class="keyword">typename</span> Algebra <span class="special">=</span> <span class="keyword">typename</span> <span class="identifier">algebra_dispatcher</span><span class="special"><</span> <span class="identifier">State</span> <span class="special">></span><span class="special">::</span><span class="identifier">algebra_type</span><span class="special">,</span> 38 <span class="keyword">typename</span> Operations <span class="special">=</span> <span class="keyword">typename</span> <span class="identifier">operations_dispatcher</span><span class="special"><</span> <span class="identifier">State</span> <span class="special">></span><span class="special">::</span><span class="identifier">operations_type</span><span class="special">,</span> 39 <span class="keyword">typename</span> Resizer <span class="special">=</span> <span class="identifier">initially_resizer</span><span class="special">></span> 40<span class="keyword">class</span> <a class="link" href="explicit_error_generic_rk.html" title="Class template explicit_error_generic_rk">explicit_error_generic_rk</a> <span class="special">:</span> <span class="keyword">public</span> <span class="identifier">explicit_error_stepper_base</span> <span class="special">{</span> 41<span class="keyword">public</span><span class="special">:</span> 42 <span class="comment">// types</span> 43 <span class="keyword">typedef</span> <span class="identifier">explicit_stepper_base</span><span class="special"><</span> <span class="special">...</span> <span class="special">></span> <a name="boost.numeric.odeint.explicit_error_generic_rk.stepper_base_type"></a><span class="identifier">stepper_base_type</span><span class="special">;</span> 44 <span class="keyword">typedef</span> <span class="identifier">stepper_base_type</span><span class="special">::</span><span class="identifier">state_type</span> <a name="boost.numeric.odeint.explicit_error_generic_rk.state_type"></a><span class="identifier">state_type</span><span class="special">;</span> 45 <span class="keyword">typedef</span> <span class="identifier">stepper_base_type</span><span class="special">::</span><span class="identifier">wrapped_state_type</span> <a name="boost.numeric.odeint.explicit_error_generic_rk.wrapped_state_type"></a><span class="identifier">wrapped_state_type</span><span class="special">;</span> 46 <span class="keyword">typedef</span> <span class="identifier">stepper_base_type</span><span class="special">::</span><span class="identifier">value_type</span> <a name="boost.numeric.odeint.explicit_error_generic_rk.value_type"></a><span class="identifier">value_type</span><span class="special">;</span> 47 <span class="keyword">typedef</span> <span class="identifier">stepper_base_type</span><span class="special">::</span><span class="identifier">deriv_type</span> <a name="boost.numeric.odeint.explicit_error_generic_rk.deriv_type"></a><span class="identifier">deriv_type</span><span class="special">;</span> 48 <span class="keyword">typedef</span> <span class="identifier">stepper_base_type</span><span class="special">::</span><span class="identifier">wrapped_deriv_type</span> <a name="boost.numeric.odeint.explicit_error_generic_rk.wrapped_deriv_type"></a><span class="identifier">wrapped_deriv_type</span><span class="special">;</span> 49 <span class="keyword">typedef</span> <span class="identifier">stepper_base_type</span><span class="special">::</span><span class="identifier">time_type</span> <a name="boost.numeric.odeint.explicit_error_generic_rk.time_type"></a><span class="identifier">time_type</span><span class="special">;</span> 50 <span class="keyword">typedef</span> <span class="identifier">stepper_base_type</span><span class="special">::</span><span class="identifier">algebra_type</span> <a name="boost.numeric.odeint.explicit_error_generic_rk.algebra_type"></a><span class="identifier">algebra_type</span><span class="special">;</span> 51 <span class="keyword">typedef</span> <span class="identifier">stepper_base_type</span><span class="special">::</span><span class="identifier">operations_type</span> <a name="boost.numeric.odeint.explicit_error_generic_rk.operations_type"></a><span class="identifier">operations_type</span><span class="special">;</span> 52 <span class="keyword">typedef</span> <span class="identifier">stepper_base_type</span><span class="special">::</span><span class="identifier">resizer_type</span> <a name="boost.numeric.odeint.explicit_error_generic_rk.resizer_type"></a><span class="identifier">resizer_type</span><span class="special">;</span> 53 <span class="keyword">typedef</span> <span class="emphasis"><em><span class="identifier">unspecified</span></em></span> <a name="boost.numeric.odeint.explicit_error_generic_rk.rk_algorithm_type"></a><span class="identifier">rk_algorithm_type</span><span class="special">;</span> 54 <span class="keyword">typedef</span> <span class="identifier">rk_algorithm_type</span><span class="special">::</span><span class="identifier">coef_a_type</span> <a name="boost.numeric.odeint.explicit_error_generic_rk.coef_a_type"></a><span class="identifier">coef_a_type</span><span class="special">;</span> 55 <span class="keyword">typedef</span> <span class="identifier">rk_algorithm_type</span><span class="special">::</span><span class="identifier">coef_b_type</span> <a name="boost.numeric.odeint.explicit_error_generic_rk.coef_b_type"></a><span class="identifier">coef_b_type</span><span class="special">;</span> 56 <span class="keyword">typedef</span> <span class="identifier">rk_algorithm_type</span><span class="special">::</span><span class="identifier">coef_c_type</span> <a name="boost.numeric.odeint.explicit_error_generic_rk.coef_c_type"></a><span class="identifier">coef_c_type</span><span class="special">;</span> 57 58 <span class="comment">// <a class="link" href="explicit_error_generic_rk.html#boost.numeric.odeint.explicit_error_generic_rkconstruct-copy-destruct">construct/copy/destruct</a></span> 59 <a class="link" href="explicit_error_generic_rk.html#idm45875526388848-bb"><span class="identifier">explicit_error_generic_rk</span></a><span class="special">(</span><span class="keyword">const</span> <span class="identifier">coef_a_type</span> <span class="special">&</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">coef_b_type</span> <span class="special">&</span><span class="special">,</span> 60 <span class="keyword">const</span> <span class="identifier">coef_b_type</span> <span class="special">&</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">coef_c_type</span> <span class="special">&</span><span class="special">,</span> 61 <span class="keyword">const</span> <span class="identifier">algebra_type</span> <span class="special">&</span> <span class="special">=</span> <span class="identifier">algebra_type</span><span class="special">(</span><span class="special">)</span><span class="special">)</span><span class="special">;</span> 62 63 <span class="comment">// <a class="link" href="explicit_error_generic_rk.html#idm45875526422928-bb">public member functions</a></span> 64 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> System<span class="special">,</span> <span class="keyword">typename</span> StateIn<span class="special">,</span> <span class="keyword">typename</span> DerivIn<span class="special">,</span> 65 <span class="keyword">typename</span> StateOut<span class="special">,</span> <span class="keyword">typename</span> Err<span class="special">></span> 66 <span class="keyword">void</span> <a class="link" href="explicit_error_generic_rk.html#idm45875526422368-bb"><span class="identifier">do_step_impl</span></a><span class="special">(</span><span class="identifier">System</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">StateIn</span> <span class="special">&</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">DerivIn</span> <span class="special">&</span><span class="special">,</span> <span class="identifier">time_type</span><span class="special">,</span> 67 <span class="identifier">StateOut</span> <span class="special">&</span><span class="special">,</span> <span class="identifier">time_type</span><span class="special">,</span> <span class="identifier">Err</span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> 68 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> System<span class="special">,</span> <span class="keyword">typename</span> StateIn<span class="special">,</span> <span class="keyword">typename</span> DerivIn<span class="special">,</span> 69 <span class="keyword">typename</span> StateOut<span class="special">></span> 70 <span class="keyword">void</span> <a class="link" href="explicit_error_generic_rk.html#idm45875526406432-bb"><span class="identifier">do_step_impl</span></a><span class="special">(</span><span class="identifier">System</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">StateIn</span> <span class="special">&</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">DerivIn</span> <span class="special">&</span><span class="special">,</span> <span class="identifier">time_type</span><span class="special">,</span> 71 <span class="identifier">StateOut</span> <span class="special">&</span><span class="special">,</span> <span class="identifier">time_type</span><span class="special">)</span><span class="special">;</span> 72 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> StateIn<span class="special">></span> <span class="keyword">void</span> <a class="link" href="explicit_error_generic_rk.html#idm45875526392624-bb"><span class="identifier">adjust_size</span></a><span class="special">(</span><span class="keyword">const</span> <span class="identifier">StateIn</span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> 73 74 <span class="comment">// <a class="link" href="explicit_error_generic_rk.html#idm45875526381712-bb">private member functions</a></span> 75 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> StateIn<span class="special">></span> <span class="keyword">bool</span> <a class="link" href="explicit_error_generic_rk.html#idm45875526381136-bb"><span class="identifier">resize_impl</span></a><span class="special">(</span><span class="keyword">const</span> <span class="identifier">StateIn</span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> 76 77 <span class="comment">// public data members</span> 78 <span class="keyword">static</span> <span class="keyword">const</span> <span class="identifier">size_t</span> <span class="identifier">stage_count</span><span class="special">;</span> 79<span class="special">}</span><span class="special">;</span></pre></div> 80<div class="refsect1"> 81<a name="idm45600373382144"></a><h2>Description</h2> 82<p>This class implements the explicit Runge-Kutta algorithms with error estimation in a generic way. The Butcher tableau is passed to the stepper which constructs the stepper scheme with the help of a template-metaprogramming algorithm. ToDo : Add example!</p> 83<p>This class derives explicit_error_stepper_base which provides the stepper interface.</p> 84<p> 85</p> 86<div class="refsect2"> 87<a name="idm45600373380592"></a><h3>Template Parameters</h3> 88<div class="orderedlist"><ol class="orderedlist" type="1"> 89<li class="listitem"> 90<pre class="literallayout"><span class="identifier">size_t</span> StageCount</pre> 91<p>The number of stages of the Runge-Kutta algorithm. </p> 92</li> 93<li class="listitem"> 94<pre class="literallayout"><span class="identifier">size_t</span> Order</pre> 95<p>The order of a stepper if the stepper is used without error estimation. </p> 96</li> 97<li class="listitem"> 98<pre class="literallayout"><span class="identifier">size_t</span> StepperOrder</pre> 99<p>The order of a step if the stepper is used with error estimation. Usually Order and StepperOrder have the same value. </p> 100</li> 101<li class="listitem"> 102<pre class="literallayout"><span class="identifier">size_t</span> ErrorOrder</pre> 103<p>The order of the error step if the stepper is used with error estimation. </p> 104</li> 105<li class="listitem"> 106<pre class="literallayout"><span class="keyword">typename</span> State</pre> 107<p>The type representing the state of the ODE. </p> 108</li> 109<li class="listitem"> 110<pre class="literallayout"><span class="keyword">typename</span> Value <span class="special">=</span> <span class="keyword">double</span></pre> 111<p>The floating point type which is used in the computations. </p> 112</li> 113<li class="listitem"><pre class="literallayout"><span class="keyword">typename</span> Deriv <span class="special">=</span> <span class="identifier">State</span></pre></li> 114<li class="listitem"> 115<pre class="literallayout"><span class="keyword">typename</span> Time <span class="special">=</span> <span class="identifier">Value</span></pre> 116<p>The type representing the independent variable - the time - of the ODE. </p> 117</li> 118<li class="listitem"> 119<pre class="literallayout"><span class="keyword">typename</span> Algebra <span class="special">=</span> <span class="keyword">typename</span> <span class="identifier">algebra_dispatcher</span><span class="special"><</span> <span class="identifier">State</span> <span class="special">></span><span class="special">::</span><span class="identifier">algebra_type</span></pre> 120<p>The algebra type. </p> 121</li> 122<li class="listitem"> 123<pre class="literallayout"><span class="keyword">typename</span> Operations <span class="special">=</span> <span class="keyword">typename</span> <span class="identifier">operations_dispatcher</span><span class="special"><</span> <span class="identifier">State</span> <span class="special">></span><span class="special">::</span><span class="identifier">operations_type</span></pre> 124<p>The operations type. </p> 125</li> 126<li class="listitem"> 127<pre class="literallayout"><span class="keyword">typename</span> Resizer <span class="special">=</span> <span class="identifier">initially_resizer</span></pre> 128<p>The resizer policy type. </p> 129</li> 130</ol></div> 131</div> 132<div class="refsect2"> 133<a name="idm45600373342080"></a><h3> 134<a name="boost.numeric.odeint.explicit_error_generic_rkconstruct-copy-destruct"></a><code class="computeroutput">explicit_error_generic_rk</code> 135 public 136 construct/copy/destruct</h3> 137<div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"> 138<pre class="literallayout"><a name="idm45875526388848-bb"></a><span class="identifier">explicit_error_generic_rk</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">coef_a_type</span> <span class="special">&</span> a<span class="special">,</span> <span class="keyword">const</span> <span class="identifier">coef_b_type</span> <span class="special">&</span> b<span class="special">,</span> 139 <span class="keyword">const</span> <span class="identifier">coef_b_type</span> <span class="special">&</span> b2<span class="special">,</span> <span class="keyword">const</span> <span class="identifier">coef_c_type</span> <span class="special">&</span> c<span class="special">,</span> 140 <span class="keyword">const</span> <span class="identifier">algebra_type</span> <span class="special">&</span> algebra <span class="special">=</span> <span class="identifier">algebra_type</span><span class="special">(</span><span class="special">)</span><span class="special">)</span><span class="special">;</span></pre>Constructs the explicit_error_generik_rk class with the given parameters a, b, b2 and c. See examples section for details on the coefficients. <p> 141</p> 142<div class="variablelist"><table border="0" class="variablelist compact"> 143<colgroup> 144<col align="left" valign="top"> 145<col> 146</colgroup> 147<tbody><tr> 148<td><p><span class="term">Parameters:</span></p></td> 149<td><div class="variablelist"><table border="0" class="variablelist compact"> 150<colgroup> 151<col align="left" valign="top"> 152<col> 153</colgroup> 154<tbody> 155<tr> 156<td><p><span class="term"><code class="computeroutput">a</code></span></p></td> 157<td><p>Triangular matrix of parameters b in the Butcher tableau. </p></td> 158</tr> 159<tr> 160<td><p><span class="term"><code class="computeroutput">algebra</code></span></p></td> 161<td><p>A copy of algebra is made and stored inside explicit_stepper_base. </p></td> 162</tr> 163<tr> 164<td><p><span class="term"><code class="computeroutput">b</code></span></p></td> 165<td><p>Last row of the butcher tableau. </p></td> 166</tr> 167<tr> 168<td><p><span class="term"><code class="computeroutput">b2</code></span></p></td> 169<td><p>Parameters for lower-order evaluation to estimate the error. </p></td> 170</tr> 171<tr> 172<td><p><span class="term"><code class="computeroutput">c</code></span></p></td> 173<td><p>Parameters to calculate the time points in the Butcher tableau. </p></td> 174</tr> 175</tbody> 176</table></div></td> 177</tr></tbody> 178</table></div> 179</li></ol></div> 180</div> 181<div class="refsect2"> 182<a name="idm45600373312144"></a><h3> 183<a name="idm45875526422928-bb"></a><code class="computeroutput">explicit_error_generic_rk</code> public member functions</h3> 184<div class="orderedlist"><ol class="orderedlist" type="1"> 185<li class="listitem"> 186<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> System<span class="special">,</span> <span class="keyword">typename</span> StateIn<span class="special">,</span> <span class="keyword">typename</span> DerivIn<span class="special">,</span> 187 <span class="keyword">typename</span> StateOut<span class="special">,</span> <span class="keyword">typename</span> Err<span class="special">></span> 188 <span class="keyword">void</span> <a name="idm45875526422368-bb"></a><span class="identifier">do_step_impl</span><span class="special">(</span><span class="identifier">System</span> system<span class="special">,</span> <span class="keyword">const</span> <span class="identifier">StateIn</span> <span class="special">&</span> in<span class="special">,</span> <span class="keyword">const</span> <span class="identifier">DerivIn</span> <span class="special">&</span> dxdt<span class="special">,</span> 189 <span class="identifier">time_type</span> t<span class="special">,</span> <span class="identifier">StateOut</span> <span class="special">&</span> out<span class="special">,</span> <span class="identifier">time_type</span> dt<span class="special">,</span> <span class="identifier">Err</span> <span class="special">&</span> xerr<span class="special">)</span><span class="special">;</span></pre>This method performs one step. The derivative <code class="computeroutput">dxdt</code> of <code class="computeroutput">in</code> at the time <code class="computeroutput">t</code> is passed to the method. The result is updated out-of-place, hence the input is in <code class="computeroutput">in</code> and the output in <code class="computeroutput">out</code>. Futhermore, an estimation of the error is stored in <code class="computeroutput">xerr</code>. <code class="computeroutput">do_step_impl</code> is used by explicit_error_stepper_base. <p> 190</p> 191<div class="variablelist"><table border="0" class="variablelist compact"> 192<colgroup> 193<col align="left" valign="top"> 194<col> 195</colgroup> 196<tbody><tr> 197<td><p><span class="term">Parameters:</span></p></td> 198<td><div class="variablelist"><table border="0" class="variablelist compact"> 199<colgroup> 200<col align="left" valign="top"> 201<col> 202</colgroup> 203<tbody> 204<tr> 205<td><p><span class="term"><code class="computeroutput">dt</code></span></p></td> 206<td><p>The step size. </p></td> 207</tr> 208<tr> 209<td><p><span class="term"><code class="computeroutput">dxdt</code></span></p></td> 210<td><p>The derivative of x at t. </p></td> 211</tr> 212<tr> 213<td><p><span class="term"><code class="computeroutput">in</code></span></p></td> 214<td><p>The state of the ODE which should be solved. in is not modified in this method </p></td> 215</tr> 216<tr> 217<td><p><span class="term"><code class="computeroutput">out</code></span></p></td> 218<td><p>The result of the step is written in out. </p></td> 219</tr> 220<tr> 221<td><p><span class="term"><code class="computeroutput">system</code></span></p></td> 222<td><p>The system function to solve, hence the r.h.s. of the ODE. It must fulfill the Simple System concept. </p></td> 223</tr> 224<tr> 225<td><p><span class="term"><code class="computeroutput">t</code></span></p></td> 226<td><p>The value of the time, at which the step should be performed. </p></td> 227</tr> 228<tr> 229<td><p><span class="term"><code class="computeroutput">xerr</code></span></p></td> 230<td><p>The result of the error estimation is written in xerr. </p></td> 231</tr> 232</tbody> 233</table></div></td> 234</tr></tbody> 235</table></div> 236</li> 237<li class="listitem"> 238<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> System<span class="special">,</span> <span class="keyword">typename</span> StateIn<span class="special">,</span> <span class="keyword">typename</span> DerivIn<span class="special">,</span> 239 <span class="keyword">typename</span> StateOut<span class="special">></span> 240 <span class="keyword">void</span> <a name="idm45875526406432-bb"></a><span class="identifier">do_step_impl</span><span class="special">(</span><span class="identifier">System</span> system<span class="special">,</span> <span class="keyword">const</span> <span class="identifier">StateIn</span> <span class="special">&</span> in<span class="special">,</span> <span class="keyword">const</span> <span class="identifier">DerivIn</span> <span class="special">&</span> dxdt<span class="special">,</span> 241 <span class="identifier">time_type</span> t<span class="special">,</span> <span class="identifier">StateOut</span> <span class="special">&</span> out<span class="special">,</span> <span class="identifier">time_type</span> dt<span class="special">)</span><span class="special">;</span></pre>This method performs one step. The derivative <code class="computeroutput">dxdt</code> of <code class="computeroutput">in</code> at the time <code class="computeroutput">t</code> is passed to the method. The result is updated out-of-place, hence the input is in <code class="computeroutput">in</code> and the output in <code class="computeroutput">out</code>. Access to this step functionality is provided by explicit_stepper_base and <code class="computeroutput">do_step_impl</code> should not be called directly. <p> 242</p> 243<div class="variablelist"><table border="0" class="variablelist compact"> 244<colgroup> 245<col align="left" valign="top"> 246<col> 247</colgroup> 248<tbody><tr> 249<td><p><span class="term">Parameters:</span></p></td> 250<td><div class="variablelist"><table border="0" class="variablelist compact"> 251<colgroup> 252<col align="left" valign="top"> 253<col> 254</colgroup> 255<tbody> 256<tr> 257<td><p><span class="term"><code class="computeroutput">dt</code></span></p></td> 258<td><p>The step size. </p></td> 259</tr> 260<tr> 261<td><p><span class="term"><code class="computeroutput">dxdt</code></span></p></td> 262<td><p>The derivative of x at t. </p></td> 263</tr> 264<tr> 265<td><p><span class="term"><code class="computeroutput">in</code></span></p></td> 266<td><p>The state of the ODE which should be solved. in is not modified in this method </p></td> 267</tr> 268<tr> 269<td><p><span class="term"><code class="computeroutput">out</code></span></p></td> 270<td><p>The result of the step is written in out. </p></td> 271</tr> 272<tr> 273<td><p><span class="term"><code class="computeroutput">system</code></span></p></td> 274<td><p>The system function to solve, hence the r.h.s. of the ODE. It must fulfill the Simple System concept. </p></td> 275</tr> 276<tr> 277<td><p><span class="term"><code class="computeroutput">t</code></span></p></td> 278<td><p>The value of the time, at which the step should be performed. </p></td> 279</tr> 280</tbody> 281</table></div></td> 282</tr></tbody> 283</table></div> 284</li> 285<li class="listitem"> 286<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> StateIn<span class="special">></span> <span class="keyword">void</span> <a name="idm45875526392624-bb"></a><span class="identifier">adjust_size</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">StateIn</span> <span class="special">&</span> x<span class="special">)</span><span class="special">;</span></pre>Adjust the size of all temporaries in the stepper manually. <p> 287</p> 288<div class="variablelist"><table border="0" class="variablelist compact"> 289<colgroup> 290<col align="left" valign="top"> 291<col> 292</colgroup> 293<tbody><tr> 294<td><p><span class="term">Parameters:</span></p></td> 295<td><div class="variablelist"><table border="0" class="variablelist compact"> 296<colgroup> 297<col align="left" valign="top"> 298<col> 299</colgroup> 300<tbody><tr> 301<td><p><span class="term"><code class="computeroutput">x</code></span></p></td> 302<td><p>A state from which the size of the temporaries to be resized is deduced. </p></td> 303</tr></tbody> 304</table></div></td> 305</tr></tbody> 306</table></div> 307</li> 308</ol></div> 309</div> 310<div class="refsect2"> 311<a name="idm45600373220368"></a><h3> 312<a name="idm45875526381712-bb"></a><code class="computeroutput">explicit_error_generic_rk</code> private member functions</h3> 313<div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> StateIn<span class="special">></span> <span class="keyword">bool</span> <a name="idm45875526381136-bb"></a><span class="identifier">resize_impl</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">StateIn</span> <span class="special">&</span> x<span class="special">)</span><span class="special">;</span></pre></li></ol></div> 314</div> 315</div> 316</div> 317<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 318<td align="left"></td> 319<td align="right"><div class="copyright-footer">Copyright © 2009-2015 Karsten Ahnert and Mario Mulansky<p> 320 Distributed under the Boost Software License, Version 1.0. (See accompanying 321 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>) 322 </p> 323</div></td> 324</tr></table> 325<hr> 326<div class="spirit-nav"> 327<a accesskey="p" href="../../../header/boost/numeric/odeint/stepper/explicit_error_generic_rk_hpp.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../../header/boost/numeric/odeint/stepper/explicit_error_generic_rk_hpp.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="../../../header/boost/numeric/odeint/stepper/explicit_generic_rk_hpp.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a> 328</div> 329</body> 330</html> 331
