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 timer</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="../../mpi/reference.html#header.boost.mpi.timer_hpp" title="Header <boost/mpi/timer.hpp>"> 10<link rel="prev" href="status.html" title="Class status"> 11<link rel="next" href="../../mpi/python.html" title="Python Bindings"> 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 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class="refentrytitle">Class timer</span></h2> 30<p>boost::mpi::timer — A simple timer that provides access to the MPI timing facilities. </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="../../mpi/reference.html#header.boost.mpi.timer_hpp" title="Header <boost/mpi/timer.hpp>">boost/mpi/timer.hpp</a>> 34 35</span> 36<span class="keyword">class</span> <a class="link" href="timer.html" title="Class timer">timer</a> <span class="special">{</span> 37<span class="keyword">public</span><span class="special">:</span> 38 <span class="comment">// <a class="link" href="timer.html#boost.mpi.timerconstruct-copy-destruct">construct/copy/destruct</a></span> 39 <a class="link" href="timer.html#id-1_3_27_7_25_2_1_1_4-bb"><span class="identifier">timer</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span> 40 41 <span class="comment">// <a class="link" href="timer.html#id-1_3_27_7_25_2_1_1_3-bb">public member functions</a></span> 42 <span class="keyword">void</span> <a class="link" href="timer.html#id-1_3_27_7_25_2_1_1_3_1-bb"><span class="identifier">restart</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span> 43 <span class="keyword">double</span> <a class="link" href="timer.html#id-1_3_27_7_25_2_1_1_3_2-bb"><span class="identifier">elapsed</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 44 <span class="keyword">double</span> <a class="link" href="timer.html#id-1_3_27_7_25_2_1_1_3_3-bb"><span class="identifier">elapsed_max</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 45 <span class="keyword">double</span> <a class="link" href="timer.html#id-1_3_27_7_25_2_1_1_3_4-bb"><span class="identifier">elapsed_min</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 46 47 <span class="comment">// <a class="link" href="timer.html#id-1_3_27_7_25_2_1_1_5-bb">public static functions</a></span> 48 <span class="keyword">static</span> <span class="keyword">bool</span> <a class="link" href="timer.html#id-1_3_27_7_25_2_1_1_5_1-bb"><span class="identifier">time_is_global</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span> 49<span class="special">}</span><span class="special">;</span></pre></div> 50<div class="refsect1"> 51<a name="id-1.3.27.7.26.4.4"></a><h2>Description</h2> 52<p>The <code class="computeroutput">timer</code> class is a simple wrapper around the MPI timing facilities that mimics the interface of the Boost Timer library. </p> 53<div class="refsect2"> 54<a name="id-1.3.27.7.26.4.4.3"></a><h3> 55<a name="boost.mpi.timerconstruct-copy-destruct"></a><code class="computeroutput">timer</code> 56 public 57 construct/copy/destruct</h3> 58<div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"> 59<pre class="literallayout"><a name="id-1_3_27_7_25_2_1_1_4-bb"></a><span class="identifier">timer</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre> 60<p>Initializes the timer</p> 61<p> 62</p> 63<div class="variablelist"><table border="0" class="variablelist compact"> 64<colgroup> 65<col align="left" valign="top"> 66<col> 67</colgroup> 68<tbody><tr> 69<td><p><span class="term">Postconditions:</span></p></td> 70<td><p><code class="computeroutput">elapsed()</code> == 0 </p></td> 71</tr></tbody> 72</table></div> 73</li></ol></div> 74</div> 75<div class="refsect2"> 76<a name="id-1.3.27.7.26.4.4.4"></a><h3> 77<a name="id-1_3_27_7_25_2_1_1_3-bb"></a><code class="computeroutput">timer</code> public member functions</h3> 78<div class="orderedlist"><ol class="orderedlist" type="1"> 79<li class="listitem"> 80<pre class="literallayout"><span class="keyword">void</span> <a name="id-1_3_27_7_25_2_1_1_3_1-bb"></a><span class="identifier">restart</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre> 81<p>Restart the timer.</p> 82<p> 83</p> 84<div class="variablelist"><table border="0" class="variablelist compact"> 85<colgroup> 86<col align="left" valign="top"> 87<col> 88</colgroup> 89<tbody><tr> 90<td><p><span class="term">Postconditions:</span></p></td> 91<td><p><code class="computeroutput">elapsed()</code> == 0 </p></td> 92</tr></tbody> 93</table></div> 94</li> 95<li class="listitem"> 96<pre class="literallayout"><span class="keyword">double</span> <a name="id-1_3_27_7_25_2_1_1_3_2-bb"></a><span class="identifier">elapsed</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 97<p>Return the amount of time that has elapsed since the last construction or reset, in seconds. </p> 98</li> 99<li class="listitem"> 100<pre class="literallayout"><span class="keyword">double</span> <a name="id-1_3_27_7_25_2_1_1_3_3-bb"></a><span class="identifier">elapsed_max</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 101<p>Return an estimate of the maximum possible value of elapsed(). Note that this routine may return too high a value on some systems. </p> 102</li> 103<li class="listitem"> 104<pre class="literallayout"><span class="keyword">double</span> <a name="id-1_3_27_7_25_2_1_1_3_4-bb"></a><span class="identifier">elapsed_min</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 105<p>Returns the minimum non-zero value that <code class="computeroutput">elapsed()</code> may return. This is the resolution of the timer. </p> 106</li> 107</ol></div> 108</div> 109<div class="refsect2"> 110<a name="id-1.3.27.7.26.4.4.5"></a><h3> 111<a name="id-1_3_27_7_25_2_1_1_5-bb"></a><code class="computeroutput">timer</code> public static functions</h3> 112<div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"> 113<pre class="literallayout"><span class="keyword">static</span> <span class="keyword">bool</span> <a name="id-1_3_27_7_25_2_1_1_5_1-bb"></a><span class="identifier">time_is_global</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre> 114<p>Determines whether the elapsed time values are global times or local processor times. </p> 115</li></ol></div> 116</div> 117</div> 118</div> 119<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 120<td align="left"></td> 121<td align="right"><div class="copyright-footer">Copyright © 2005-2007 Douglas Gregor, 122 Matthias Troyer, Trustees of Indiana University<p> 123 Distributed under the Boost Software License, Version 1.0. (See accompanying 124 file LICENSE_1_0.txt or copy at <ulink url="http://www.boost.org/LICENSE_1_0.txt"> 125 http://www.boost.org/LICENSE_1_0.txt </ulink>) 126 </p> 127</div></td> 128</tr></table> 129<hr> 130<div class="spirit-nav"> 131<a accesskey="p" href="status.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../mpi/reference.html#header.boost.mpi.timer_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="../../mpi/python.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a> 132</div> 133</body> 134</html> 135
