mirror of
https://github.com/boostorg/odeint.git
synced 2025-05-09 23:24:01 +00:00
265 lines
13 KiB
HTML
265 lines
13 KiB
HTML
<html>
|
|
<head>
|
|
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
|
|
<title>Stepper</title>
|
|
<link rel="stylesheet" href="../../boostbook.css" type="text/css">
|
|
<meta name="generator" content="DocBook XSL Stylesheets V1.75.2">
|
|
<link rel="home" href="../../index.html" title="Chapter 1. Boost.Numeric.Odeint">
|
|
<link rel="up" href="../concepts.html" title="Concepts">
|
|
<link rel="prev" href="implicit_system.html" title="Implicit System">
|
|
<link rel="next" href="error_stepper.html" title="Error Stepper">
|
|
</head>
|
|
<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
|
|
<div class="spirit-nav">
|
|
<a accesskey="p" href="implicit_system.html"><img src="../../images/prev.png" alt="Prev"></a><a accesskey="u" href="../concepts.html"><img src="../../images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../images/home.png" alt="Home"></a><a accesskey="n" href="error_stepper.html"><img src="../../images/next.png" alt="Next"></a>
|
|
</div>
|
|
<div class="section">
|
|
<div class="titlepage"><div><div><h3 class="title">
|
|
<a name="boost_numeric_odeint.concepts.stepper"></a><a class="link" href="stepper.html" title="Stepper">Stepper</a>
|
|
</h3></div></div></div>
|
|
<p>
|
|
This concepts specifies the interface a simple stepper has to fulfill to
|
|
be used within the <a class="link" href="../odeint_in_detail/integrate_functions.html" title="Integrate functions">integrate
|
|
functions</a>.
|
|
</p>
|
|
<h5>
|
|
<a name="boost_numeric_odeint.concepts.stepper.h0"></a>
|
|
<span><a name="boost_numeric_odeint.concepts.stepper.description"></a></span><a class="link" href="stepper.html#boost_numeric_odeint.concepts.stepper.description">Description</a>
|
|
</h5>
|
|
<p>
|
|
The basic stepper concept. A basic stepper following this Stepper concept
|
|
is able to perform a single step of the solution <span class="emphasis"><em>x(t)</em></span>
|
|
of an ODE to obtain <span class="emphasis"><em>x(t+dt)</em></span> using a given step size
|
|
<span class="emphasis"><em>dt</em></span>. Basic steppers can be Runge Kutta steppers, symplectic
|
|
steppers as well as implicit steppers. Depending on the actual stepper, the
|
|
ODE is defined as <a class="link" href="system.html" title="System">System</a>,
|
|
<a class="link" href="symplectic_system.html" title="Symplectic System">Symplectic
|
|
System</a>, <a class="link" href="simple_symplectic_system.html" title="Simple Symplectic System">Simple
|
|
Symplectic System</a> or <a class="link" href="implicit_system.html" title="Implicit System">Implicit
|
|
System</a>. Note that all error steppers are also basic steppers.
|
|
</p>
|
|
<h5>
|
|
<a name="boost_numeric_odeint.concepts.stepper.h1"></a>
|
|
<span><a name="boost_numeric_odeint.concepts.stepper.refinement_of"></a></span><a class="link" href="stepper.html#boost_numeric_odeint.concepts.stepper.refinement_of">Refinement
|
|
of</a>
|
|
</h5>
|
|
<div class="itemizedlist"><ul class="itemizedlist" type="disc">
|
|
<li class="listitem">
|
|
DefaultConstructable
|
|
</li>
|
|
<li class="listitem">
|
|
CopyConstructable
|
|
</li>
|
|
</ul></div>
|
|
<h5>
|
|
<a name="boost_numeric_odeint.concepts.stepper.h2"></a>
|
|
<span><a name="boost_numeric_odeint.concepts.stepper.associated_types"></a></span><a class="link" href="stepper.html#boost_numeric_odeint.concepts.stepper.associated_types">Associated
|
|
types</a>
|
|
</h5>
|
|
<div class="itemizedlist"><ul class="itemizedlist" type="disc">
|
|
<li class="listitem">
|
|
<p><span class="bold"><strong>state_type</strong></span></p>
|
|
<p><code class="computeroutput"><span class="identifier">Stepper</span><span class="special">::</span><span class="identifier">state_type</span></code></p>
|
|
<p>The
|
|
type characterizing the state of the ODE, hence <span class="emphasis"><em>x</em></span>.</p>
|
|
</li>
|
|
<li class="listitem">
|
|
<p><span class="bold"><strong>deriv_type</strong></span></p>
|
|
<p><code class="computeroutput"><span class="identifier">Stepper</span><span class="special">::</span><span class="identifier">deriv_type</span></code></p>
|
|
<p>The
|
|
type characterizing the derivative of the ODE, hence <span class="emphasis"><em>d x/dt</em></span>.</p>
|
|
</li>
|
|
<li class="listitem">
|
|
<p><span class="bold"><strong>time_type</strong></span></p>
|
|
<p><code class="computeroutput"><span class="identifier">Stepper</span><span class="special">::</span><span class="identifier">time_type</span></code></p>
|
|
<p>The
|
|
type characterizing the dependent variable of the ODE, hence the time
|
|
<span class="emphasis"><em>t</em></span>.</p>
|
|
</li>
|
|
<li class="listitem">
|
|
<p><span class="bold"><strong>value_type</strong></span></p>
|
|
<p><code class="computeroutput"><span class="identifier">Stepper</span><span class="special">::</span><span class="identifier">value_type</span></code></p>
|
|
<p>The
|
|
numerical data type which is used within the stepper, something like
|
|
<code class="computeroutput"><span class="keyword">float</span></code>, <code class="computeroutput"><span class="keyword">double</span></code>,
|
|
<code class="computeroutput"><span class="identifier">complex</span><span class="special">&</span><span class="identifier">lt</span><span class="special">;</span> <span class="keyword">double</span> <span class="special">&</span><span class="identifier">gt</span><span class="special">;</span></code>.</p>
|
|
</li>
|
|
<li class="listitem">
|
|
<p><span class="bold"><strong>order_type</strong></span></p>
|
|
<p><code class="computeroutput"><span class="identifier">Stepper</span><span class="special">::</span><span class="identifier">order_type</span></code></p>
|
|
<p>The
|
|
type characterizing the order of the ODE, typically <code class="computeroutput"><span class="keyword">unsigned</span>
|
|
<span class="keyword">short</span></code>.</p>
|
|
</li>
|
|
</ul></div>
|
|
<h5>
|
|
<a name="boost_numeric_odeint.concepts.stepper.h3"></a>
|
|
<span><a name="boost_numeric_odeint.concepts.stepper.notation"></a></span><a class="link" href="stepper.html#boost_numeric_odeint.concepts.stepper.notation">Notation</a>
|
|
</h5>
|
|
<div class="variablelist">
|
|
<p class="title"><b></b></p>
|
|
<dl>
|
|
<dt><span class="term"><code class="computeroutput"><span class="identifier">Stepper</span></code></span></dt>
|
|
<dd><p>
|
|
A type that is a model of Stepper
|
|
</p></dd>
|
|
<dt><span class="term"><code class="computeroutput"><span class="identifier">State</span></code></span></dt>
|
|
<dd><p>
|
|
A type representing the state <span class="emphasis"><em>x</em></span> of the ODE
|
|
</p></dd>
|
|
<dt><span class="term"><code class="computeroutput"><span class="identifier">Time</span></code></span></dt>
|
|
<dd><p>
|
|
A type representing the time <span class="emphasis"><em>t</em></span> of the ODE
|
|
</p></dd>
|
|
<dt><span class="term"><code class="computeroutput"><span class="identifier">stepper</span></code></span></dt>
|
|
<dd><p>
|
|
An object of type <code class="computeroutput"><span class="identifier">Stepper</span></code>
|
|
</p></dd>
|
|
<dt><span class="term"><code class="computeroutput"><span class="identifier">x</span></code></span></dt>
|
|
<dd><p>
|
|
Object of type <code class="computeroutput"><span class="identifier">State</span></code>
|
|
</p></dd>
|
|
<dt><span class="term"><code class="computeroutput"><span class="identifier">t</span></code>, <code class="computeroutput"><span class="identifier">dt</span></code></span></dt>
|
|
<dd><p>
|
|
Objects of type <code class="computeroutput"><span class="identifier">Time</span></code>
|
|
</p></dd>
|
|
<dt><span class="term"><code class="computeroutput"><span class="identifier">sys</span></code></span></dt>
|
|
<dd><p>
|
|
An object defining the ODE. Depending on the Stepper this might be
|
|
a model of <a class="link" href="system.html" title="System">System</a>,
|
|
<a class="link" href="symplectic_system.html" title="Symplectic System">Symplectic
|
|
System</a>, <a class="link" href="simple_symplectic_system.html" title="Simple Symplectic System">Simple
|
|
Symplectic System</a> or <a class="link" href="implicit_system.html" title="Implicit System">Implicit
|
|
System</a>
|
|
</p></dd>
|
|
</dl>
|
|
</div>
|
|
<h5>
|
|
<a name="boost_numeric_odeint.concepts.stepper.h4"></a>
|
|
<span><a name="boost_numeric_odeint.concepts.stepper.valid_expressions"></a></span><a class="link" href="stepper.html#boost_numeric_odeint.concepts.stepper.valid_expressions">Valid Expressions</a>
|
|
</h5>
|
|
<div class="informaltable"><table class="table">
|
|
<colgroup>
|
|
<col>
|
|
<col>
|
|
<col>
|
|
<col>
|
|
</colgroup>
|
|
<thead><tr>
|
|
<th>
|
|
<p>
|
|
Name
|
|
</p>
|
|
</th>
|
|
<th>
|
|
<p>
|
|
Expression
|
|
</p>
|
|
</th>
|
|
<th>
|
|
<p>
|
|
Type
|
|
</p>
|
|
</th>
|
|
<th>
|
|
<p>
|
|
Semantics
|
|
</p>
|
|
</th>
|
|
</tr></thead>
|
|
<tbody>
|
|
<tr>
|
|
<td>
|
|
<p>
|
|
Get the order
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
<code class="computeroutput"><span class="identifier">stepper</span><span class="special">.</span><span class="identifier">order</span><span class="special">()</span></code>
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
<code class="computeroutput"><span class="identifier">order_type</span></code>
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
Returns the order of the stepper.
|
|
</p>
|
|
</td>
|
|
</tr>
|
|
<tr>
|
|
<td>
|
|
<p>
|
|
Do step
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
<code class="computeroutput"><span class="identifier">stepper</span><span class="special">.</span><span class="identifier">do_step</span><span class="special">(</span>
|
|
<span class="identifier">sys</span> <span class="special">,</span>
|
|
<span class="identifier">x</span> <span class="special">,</span>
|
|
<span class="identifier">t</span> <span class="special">,</span>
|
|
<span class="identifier">dt</span> <span class="special">)</span></code>
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
<code class="computeroutput"><span class="keyword">void</span></code>
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
Performs one step of step size <code class="computeroutput"><span class="identifier">dt</span></code>.
|
|
The newly obtained state is written in place in <code class="computeroutput"><span class="identifier">x</span></code>.
|
|
</p>
|
|
</td>
|
|
</tr>
|
|
</tbody>
|
|
</table></div>
|
|
<h5>
|
|
<a name="boost_numeric_odeint.concepts.stepper.h5"></a>
|
|
<span><a name="boost_numeric_odeint.concepts.stepper.models"></a></span><a class="link" href="stepper.html#boost_numeric_odeint.concepts.stepper.models">Models</a>
|
|
</h5>
|
|
<div class="itemizedlist"><ul class="itemizedlist" type="disc">
|
|
<li class="listitem">
|
|
<code class="computeroutput"><span class="identifier">runge_kutta4</span></code>
|
|
</li>
|
|
<li class="listitem">
|
|
<code class="computeroutput"><span class="identifier">euler</span></code>
|
|
</li>
|
|
<li class="listitem">
|
|
<code class="computeroutput"><span class="identifier">runge_kutta_cash_karp54</span></code>
|
|
</li>
|
|
<li class="listitem">
|
|
<code class="computeroutput"><span class="identifier">runge_kutta_dopri5</span></code>
|
|
</li>
|
|
<li class="listitem">
|
|
<code class="computeroutput"><span class="identifier">runge_kutta_fehlberg78</span></code>
|
|
</li>
|
|
<li class="listitem">
|
|
<code class="computeroutput"><span class="identifier">modified_midpoint</span></code>
|
|
</li>
|
|
<li class="listitem">
|
|
<code class="computeroutput"><span class="identifier">rosenbrock4</span></code>
|
|
</li>
|
|
</ul></div>
|
|
</div>
|
|
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
|
|
<td align="left"></td>
|
|
<td align="right"><div class="copyright-footer">Copyright © 2009-2011 Karsten Ahnert
|
|
and Mario Mulansky<p>
|
|
Distributed under the Boost Software License, Version 1.0. (See accompanying
|
|
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>)
|
|
</p>
|
|
</div></td>
|
|
</tr></table>
|
|
<hr>
|
|
<div class="spirit-nav">
|
|
<a accesskey="p" href="implicit_system.html"><img src="../../images/prev.png" alt="Prev"></a><a accesskey="u" href="../concepts.html"><img src="../../images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../images/home.png" alt="Home"></a><a accesskey="n" href="error_stepper.html"><img src="../../images/next.png" alt="Next"></a>
|
|
</div>
|
|
</body>
|
|
</html>
|