/usr/include/boost/random/exponential_distribution.hpp is in libboost1.46-dev 1.46.1-7ubuntu3.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 | /* boost random/exponential_distribution.hpp header file
*
* Copyright Jens Maurer 2000-2001
* Distributed under the Boost Software License, Version 1.0. (See
* accompanying file LICENSE_1_0.txt or copy at
* http://www.boost.org/LICENSE_1_0.txt)
*
* See http://www.boost.org for most recent version including documentation.
*
* $Id: exponential_distribution.hpp 60755 2010-03-22 00:45:06Z steven_watanabe $
*
* Revision history
* 2001-02-18 moved to individual header files
*/
#ifndef BOOST_RANDOM_EXPONENTIAL_DISTRIBUTION_HPP
#define BOOST_RANDOM_EXPONENTIAL_DISTRIBUTION_HPP
#include <boost/config/no_tr1/cmath.hpp>
#include <cassert>
#include <iostream>
#include <boost/limits.hpp>
#include <boost/static_assert.hpp>
#include <boost/random/detail/config.hpp>
namespace boost {
/**
* The exponential distribution has a single parameter lambda.
*
* It has \f$p(x) = \lambda e^{-\lambda x}\f$
*/
template<class RealType = double>
class exponential_distribution
{
public:
typedef RealType input_type;
typedef RealType result_type;
#if !defined(BOOST_NO_LIMITS_COMPILE_TIME_CONSTANTS) && !(defined(BOOST_MSVC) && BOOST_MSVC <= 1300)
BOOST_STATIC_ASSERT(!std::numeric_limits<RealType>::is_integer);
#endif
explicit exponential_distribution(result_type lambda_arg = result_type(1))
: _lambda(lambda_arg) { assert(_lambda > result_type(0)); }
// compiler-generated copy ctor and assignment operator are fine
result_type lambda() const { return _lambda; }
void reset() { }
template<class Engine>
result_type operator()(Engine& eng)
{
#ifndef BOOST_NO_STDC_NAMESPACE
using std::log;
#endif
return -result_type(1) / _lambda * log(result_type(1)-eng());
}
#ifndef BOOST_RANDOM_NO_STREAM_OPERATORS
template<class CharT, class Traits>
friend std::basic_ostream<CharT,Traits>&
operator<<(std::basic_ostream<CharT,Traits>& os, const exponential_distribution& ed)
{
os << ed._lambda;
return os;
}
template<class CharT, class Traits>
friend std::basic_istream<CharT,Traits>&
operator>>(std::basic_istream<CharT,Traits>& is, exponential_distribution& ed)
{
is >> std::ws >> ed._lambda;
return is;
}
#endif
private:
result_type _lambda;
};
} // namespace boost
#endif // BOOST_RANDOM_EXPONENTIAL_DISTRIBUTION_HPP
|