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29 </h3></div></div></div>
31 <a href=
"http://en.wikipedia.org/wiki/Random_variate" target=
"_top">Random variates
</a>
32 and
<a href=
"http://en.wikipedia.org/wiki/Parameter" target=
"_top">distribution parameters
</a>
33 are conventionally distinguished (for example in Wikipedia and Wolfram MathWorld
34 by placing a semi-colon after the
<a href=
"http://en.wikipedia.org/wiki/Random_variate" target=
"_top">random
35 variate
</a> (whose value you 'choose'), to separate the variate from
36 the parameter(s) that defines the shape of the distribution.
39 For example, the binomial distribution has two parameters: n (the number
40 of trials) and p (the probability of success on one trial). It also has the
41 <a href=
"http://en.wikipedia.org/wiki/Random_variate" target=
"_top">random variate
</a>
42 <span class=
"emphasis"><em>k
</em></span>: the number of successes observed. This means the
43 probability density/mass function (pdf) is written as
<span class=
"emphasis"><em>f(k; n, p)
</em></span>.
46 Translating this into code the
<code class=
"computeroutput"><span class=
"identifier">binomial_distribution
</span></code>
47 constructor therefore has two parameters:
49 <pre class=
"programlisting"><span class=
"identifier">binomial_distribution
</span><span class=
"special">(
</span><span class=
"identifier">RealType
</span> <span class=
"identifier">n
</span><span class=
"special">,
</span> <span class=
"identifier">RealType
</span> <span class=
"identifier">p
</span><span class=
"special">);
</span>
52 While the function
<code class=
"computeroutput"><span class=
"identifier">pdf
</span></code> has
53 one argument specifying the distribution type (which includes its parameters,
54 if any), and a second argument for the
<a href=
"http://en.wikipedia.org/wiki/Random_variate" target=
"_top">random
55 variate
</a>. So taking our binomial distribution example, we would write:
57 <pre class=
"programlisting"><span class=
"identifier">pdf
</span><span class=
"special">(
</span><span class=
"identifier">binomial_distribution
</span><span class=
"special"><</span><span class=
"identifier">RealType
</span><span class=
"special">>(
</span><span class=
"identifier">n
</span><span class=
"special">,
</span> <span class=
"identifier">p
</span><span class=
"special">),
</span> <span class=
"identifier">k
</span><span class=
"special">);
</span>
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© 2006-
2010,
2012-
2014 Nikhar Agrawal,
63 Anton Bikineev, Paul A. Bristow, Marco Guazzone, Christopher Kormanyos, Hubert
64 Holin, Bruno Lalande, John Maddock, Jeremy Murphy, Johan R
åde, Gautam Sewani,
65 Benjamin Sobotta, Thijs van den Berg, Daryle Walker and Xiaogang Zhang
<p>
66 Distributed under the Boost Software License, Version
1.0. (See accompanying
67 file LICENSE_1_0.txt or copy at
<a href=
"http://www.boost.org/LICENSE_1_0.txt" target=
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