[rand.dist.norm.cauchy]. I'm having trouble testing the output as all statistical properties are undefined. They do not converge upon any one value as the number of samples increases. Suggestions for tests welcome.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@103983 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/random b/include/random
index a1278fe..c173414 100644
--- a/include/random
+++ b/include/random
@@ -1219,7 +1219,6 @@
result_type min() const;
result_type max() const;
-
friend bool operator==(const chi_squared_distribution& x,
const chi_squared_distribution& y);
friend bool operator!=(const chi_squared_distribution& x,
@@ -1239,7 +1238,62 @@
};
template<class RealType = double>
- class cauchy_distribution;
+class cauchy_distribution
+{
+public:
+ // types
+ typedef RealType result_type;
+
+ class param_type
+ {
+ public:
+ typedef cauchy_distribution distribution_type;
+
+ explicit param_type(result_type a = 0, result_type b = 1);
+
+ result_type a() const;
+ result_type b() const;
+
+ friend bool operator==(const param_type& x, const param_type& y);
+ friend bool operator!=(const param_type& x, const param_type& y);
+ };
+
+ // constructor and reset functions
+ explicit cauchy_distribution(result_type a = 0, result_type b = 1);
+ explicit cauchy_distribution(const param_type& parm);
+ void reset();
+
+ // generating functions
+ template<class URNG> result_type operator()(URNG& g);
+ template<class URNG> result_type operator()(URNG& g, const param_type& parm);
+
+ // property functions
+ result_type a() const;
+ result_type b() const;
+
+ param_type param() const;
+ void param(const param_type& parm);
+
+ result_type min() const;
+ result_type max() const;
+
+ friend bool operator==(const cauchy_distribution& x,
+ const cauchy_distribution& y);
+ friend bool operator!=(const cauchy_distribution& x,
+ const cauchy_distribution& y);
+
+ template <class charT, class traits>
+ friend
+ basic_ostream<charT, traits>&
+ operator<<(basic_ostream<charT, traits>& os,
+ const cauchy_distribution& x);
+
+ template <class charT, class traits>
+ friend
+ basic_istream<charT, traits>&
+ operator>>(basic_istream<charT, traits>& is,
+ cauchy_distribution& x);
+};
template<class RealType = double>
class fisher_f_distribution;
@@ -4807,6 +4861,122 @@
return __is;
}
+// cauchy_distribution
+
+template<class _RealType = double>
+class cauchy_distribution
+{
+public:
+ // types
+ typedef _RealType result_type;
+
+ class param_type
+ {
+ result_type __a_;
+ result_type __b_;
+ public:
+ typedef cauchy_distribution distribution_type;
+
+ explicit param_type(result_type __a = 0, result_type __b = 1)
+ : __a_(__a), __b_(__b) {}
+
+ result_type a() const {return __a_;}
+ result_type b() const {return __b_;}
+
+ friend bool operator==(const param_type& __x, const param_type& __y)
+ {return __x.__a_ == __y.__a_ && __x.__b_ == __y.__b_;}
+ friend bool operator!=(const param_type& __x, const param_type& __y)
+ {return !(__x == __y);}
+ };
+
+private:
+ param_type __p_;
+
+public:
+ // constructor and reset functions
+ explicit cauchy_distribution(result_type __a = 0, result_type __b = 1)
+ : __p_(param_type(__a, __b)) {}
+ explicit cauchy_distribution(const param_type& __p)
+ : __p_(__p) {}
+ void reset() {}
+
+ // generating functions
+ template<class _URNG> result_type operator()(_URNG& __g)
+ {return (*this)(__g, __p_);}
+ template<class _URNG> result_type operator()(_URNG& __g, const param_type& __p);
+
+ // property functions
+ result_type a() const {return __p_.a();}
+ result_type b() const {return __p_.b();}
+
+ param_type param() const {return __p_;}
+ void param(const param_type& __p) {__p_ = __p;}
+
+ result_type min() const {return -numeric_limits<result_type>::infinity();}
+ result_type max() const {return numeric_limits<result_type>::infinity();}
+
+ friend bool operator==(const cauchy_distribution& __x,
+ const cauchy_distribution& __y)
+ {return __x.__p_ == __y.__p_;}
+ friend bool operator!=(const cauchy_distribution& __x,
+ const cauchy_distribution& __y)
+ {return !(__x == __y);}
+
+ template <class _CharT, class _Traits, class _RT>
+ friend
+ basic_ostream<_CharT, _Traits>&
+ operator<<(basic_ostream<_CharT, _Traits>& __os,
+ const cauchy_distribution<_RT>& __x);
+
+ template <class _CharT, class _Traits, class _RT>
+ friend
+ basic_istream<_CharT, _Traits>&
+ operator>>(basic_istream<_CharT, _Traits>& __is,
+ cauchy_distribution<_RT>& __x);
+};
+
+template <class _RealType>
+template<class _URNG>
+inline
+_RealType
+cauchy_distribution<_RealType>::operator()(_URNG& __g, const param_type& __p)
+{
+ uniform_real_distribution<result_type> __gen;
+ // purposefully let tan arg get as close to pi/2 as it wants, tan will return a finite
+ return __p.a() + __p.b() * _STD::tan(3.1415926535897932384626433832795 * __gen(__g));
+}
+
+template <class _CharT, class _Traits, class _RT>
+basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os,
+ const cauchy_distribution<_RT>& __x)
+{
+ __save_flags<_CharT, _Traits> _(__os);
+ __os.flags(ios_base::dec | ios_base::left);
+ _CharT __sp = __os.widen(' ');
+ __os.fill(__sp);
+ __os << __x.a() << __sp << __x.b();
+ return __os;
+}
+
+template <class _CharT, class _Traits, class _RT>
+basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is,
+ cauchy_distribution<_RT>& __x)
+{
+ typedef cauchy_distribution<_RT> _Eng;
+ typedef typename _Eng::result_type result_type;
+ typedef typename _Eng::param_type param_type;
+ __save_flags<_CharT, _Traits> _(__is);
+ __is.flags(ios_base::dec | ios_base::skipws);
+ result_type __a;
+ result_type __b;
+ __is >> __a >> __b;
+ if (!__is.fail())
+ __x.param(param_type(__a, __b));
+ return __is;
+}
+
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP_RANDOM
