devn00b
/
EQ2EMu


			
				
					
						
						
							1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677787980818283848586878889
							<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
<title>Performance</title>
<link rel="stylesheet" href="../math.css" type="text/css">
<meta name="generator" content="DocBook XSL Stylesheets V1.79.1">
<link rel="home" href="../index.html" title="Math Toolkit 2.11.0">
<link rel="up" href="../overview.html" title="Chapter&#160;1.&#160;Overview">
<link rel="prev" href="threads.html" title="Thread Safety">
<link rel="next" href="building.html" title="If and How to Build a Boost.Math Library, and its Examples and Tests">
</head>
<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
<table cellpadding="2" width="100%"><tr>
<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../../boost.png"></td>
<td align="center"><a href="../../../../../index.html">Home</a></td>
<td align="center"><a href="../../../../../libs/libraries.htm">Libraries</a></td>
<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td>
<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td>
<td align="center"><a href="../../../../../more/index.htm">More</a></td>
</tr></table>
<hr>
<div class="spirit-nav">
<a accesskey="p" href="threads.html"><img src="../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../overview.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="building.html"><img src="../../../../../doc/src/images/next.png" alt="Next"></a>
</div>
<div class="section">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="math_toolkit.perf_over1"></a><a class="link" href="perf_over1.html" title="Performance">Performance</a>
</h2></div></div></div>
<p>
      By and large the performance of this library should be acceptable for most
      needs. However, often the library has to make a choice whether to be accurate
      or fast and by default it chooses accuracy over speed. If you would rather
      have fast rather than fully accurate routines, then refer to the <a class="link" href="../perf.html" title="Chapter&#160;21.&#160;Performance">performance
      section</a> for information and examples on how to achieve this.
    </p>
<p>
      In terms of the algorithms used, this library aims to use the same "best
      of breed" algorithms as many other libraries: the principle difference
      is that this library is implemented in C++ - taking advantage of all the abstraction
      mechanisms that C++ offers - where as most traditional numeric libraries are
      implemented in C or FORTRAN. Traditionally languages such as C or FORTRAN are
      perceived as easier to optimise than more complex languages like C++, so in
      a sense this library provides a good test of current compiler technology, and
      the "abstraction penalty" - if any - of C++ compared to other languages.
    </p>
<p>
      The three most important things you can do to ensure the best performance from
      this library are:
    </p>
<div class="orderedlist"><ol class="orderedlist" type="1">
<li class="listitem">
          Turn on your compilers optimisations: the difference between "release"
          and "debug" builds can easily be a <a class="link" href="getting_best.html" title="Getting the Best Performance from this Library: Compiler and Compiler Options">factor
          of 20</a>.
        </li>
<li class="listitem">
          Pick your compiler carefully: <a class="link" href="comp_compilers.html" title="Comparing Different Compilers">performance
          differences of up to 8 fold</a> have been found between some Windows
          compilers for example.
        </li>
<li class="listitem">
          Disable internal use of <code class="computeroutput"><span class="keyword">long</span> <span class="keyword">double</span></code>, this will reduce accuracy but typically
          yield a 2x speedup on modern x64 hardware/compilers.
        </li>
</ol></div>
<p>
      The <a class="link" href="../perf.html" title="Chapter&#160;21.&#160;Performance">performance section</a> contains more information
      on the performance of this library, what you can do to fine tune it, and how
      this library compares to some other open source alternatives.
    </p>
</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 &#169; 2006-2019 Nikhar
      Agrawal, Anton Bikineev, Paul A. Bristow, Marco Guazzone, Christopher Kormanyos,
      Hubert Holin, Bruno Lalande, John Maddock, Jeremy Murphy, Matthew Pulver, Johan
      R&#229;de, Gautam Sewani, Benjamin Sobotta, Nicholas Thompson, Thijs van den Berg,
      Daryle Walker and Xiaogang Zhang<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="threads.html"><img src="../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../overview.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="building.html"><img src="../../../../../doc/src/images/next.png" alt="Next"></a>
</div>
</body>
</html>