Implement the Nakagami statistical distribution as an extension.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@191434 138bc75d-0d04-0410-961f-82ee72b054a4

10 files changed, 598 insertions, 0 deletions

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index a687a48ccb0..a9ee74a1304 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,21 @@
+2012-09-18  Edward Smith-Rowland  <3dw4rd@verizon.net>
+
+	* include/ext/random: Add __gnu_cxx::nakagami_distribution<> class.
+	* include/ext/random.tcc: Add out-of-line functions for
+	__gnu_cxx::nakagami_distribution<>.
+	* testsuite/ext/random/nakagami_distribution/operators/equal.cc:
+	New file.
+	* testsuite/ext/random/nakagami_distribution/operators/serialize.cc:
+	New file.
+	* testsuite/ext/random/nakagami_distribution/operators/inequal.cc:
+	New file.
+	* testsuite/ext/random/nakagami_distribution/cons/parms.cc: New file.
+	* testsuite/ext/random/nakagami_distribution/cons/default.cc: New file.
+	* testsuite/ext/random/nakagami_distribution/requirements/typedefs.cc:
+	New file.
+	* testsuite/ext/random/nakagami_distribution/requirements/
+	explicit_instantiation/1.cc: New file.
+
 2012-09-18  Paolo Carlini  <paolo.carlini@oracle.com>
 
 	PR libstdc++/54612
diff --git a/libstdc++-v3/include/ext/random b/libstdc++-v3/include/ext/random
index 08b7f3ef8fb..f413cef7221 100644
--- a/libstdc++-v3/include/ext/random
+++ b/libstdc++-v3/include/ext/random
@@ -1139,6 +1139,227 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	       const rice_distribution<_RealType1>& __d2)
     { return !(__d1 == __d2); }
 
+
+  /**
+   * @brief A Nakagami continuous distribution for random numbers.
+   *
+   * The formula for the Nakagami probability density function is
+   * @f[
+   *     p(x|\mu,\omega) = \frac{2\mu^\mu}{\Gamma(\mu)\omega^\mu}
+   *                       x^{2\mu-1}e^{-\mu x / \omega}
+   * @f]
+   * where @f$\Gamma(z)@f$ is the gamma function and @f$\mu >= 0.5@f$
+   * and @f$\omega > 0@f$.
+   */
+  template<typename _RealType = double>
+    class
+    nakagami_distribution
+    {
+      static_assert(std::is_floating_point<_RealType>::value,
+		    "template argument not a floating point type");
+
+    public:
+      /** The type of the range of the distribution. */
+      typedef _RealType result_type;
+      /** Parameter type. */
+      struct param_type
+      {
+	typedef nakagami_distribution<result_type> distribution_type;
+
+	param_type(result_type __mu = result_type(1),
+		   result_type __omega = result_type(1))
+	: _M_mu(__mu), _M_omega(__omega)
+	{
+	  _GLIBCXX_DEBUG_ASSERT(_M_mu >= result_type(0.5L));
+	  _GLIBCXX_DEBUG_ASSERT(_M_omega > result_type(0));
+	}
+
+	result_type
+	mu() const
+	{ return _M_mu; }
+
+	result_type
+	omega() const
+	{ return _M_omega; }
+
+	friend bool
+	operator==(const param_type& __p1, const param_type& __p2)
+	{ return __p1._M_mu == __p2._M_mu
+              && __p1._M_omega == __p2._M_omega; }
+
+      private:
+	void _M_initialize();
+
+	result_type _M_mu;
+	result_type _M_omega;
+      };
+
+      /**
+       * @brief Constructors.
+       */
+      explicit
+      nakagami_distribution(result_type __mu = result_type(1),
+			    result_type __omega = result_type(1))
+      : _M_param(__mu, __omega),
+	_M_gd(__mu, __omega / __mu)
+      { }
+
+      explicit
+      nakagami_distribution(const param_type& __p)
+      : _M_param(__p),
+	_M_gd(__p.mu(), __p.omega() / __p.mu())
+      { }
+
+      /**
+       * @brief Resets the distribution state.
+       */
+      void
+      reset()
+      { _M_gd.reset(); }
+
+      /**
+       * @brief Return the parameters of the distribution.
+       */
+      result_type
+      mu() const
+      { return _M_param.mu(); }
+
+      result_type
+      omega() const
+      { return _M_param.omega(); }
+
+      /**
+       * @brief Returns the parameter set of the distribution.
+       */
+      param_type
+      param() const
+      { return _M_param; }
+
+      /**
+       * @brief Sets the parameter set of the distribution.
+       * @param __param The new parameter set of the distribution.
+       */
+      void
+      param(const param_type& __param)
+      { _M_param = __param; }
+
+      /**
+       * @brief Returns the greatest lower bound value of the distribution.
+       */
+      result_type
+      min() const
+      { return result_type(0); }
+
+      /**
+       * @brief Returns the least upper bound value of the distribution.
+       */
+      result_type
+      max() const
+      { return std::numeric_limits<result_type>::max(); }
+
+      /**
+       * @brief Generating functions.
+       */
+      template<typename _UniformRandomNumberGenerator>
+	result_type
+	operator()(_UniformRandomNumberGenerator& __urng)
+	{ return std::sqrt(this->_M_gd(__urng)); }
+
+      template<typename _UniformRandomNumberGenerator>
+	result_type
+	operator()(_UniformRandomNumberGenerator& __urng,
+		   const param_type& __p)
+        {
+	  typename std::gamma_distribution<result_type>::param_type
+	    __pg(__p.mu(), __p.omega() / __p.mu());
+	  return std::sqrt(this->_M_gd(__pg, __urng));
+	}
+
+      template<typename _ForwardIterator,
+	       typename _UniformRandomNumberGenerator>
+	void
+	__generate(_ForwardIterator __f, _ForwardIterator __t,
+		   _UniformRandomNumberGenerator& __urng)
+	{ this->__generate(__f, __t, __urng, this->param()); }
+
+      template<typename _ForwardIterator,
+	       typename _UniformRandomNumberGenerator>
+	void
+	__generate(_ForwardIterator __f, _ForwardIterator __t,
+		   _UniformRandomNumberGenerator& __urng,
+		   const param_type& __p)
+	{ this->__generate_impl(__f, __t, __urng, __p); }
+
+      template<typename _UniformRandomNumberGenerator>
+	void
+	__generate(result_type* __f, result_type* __t,
+		   _UniformRandomNumberGenerator& __urng,
+		   const param_type& __p)
+	{ this->__generate_impl(__f, __t, __urng, __p); }
+
+      /**
+       * @brief Return true if two Nakagami distributions have
+       *        the same parameters and the sequences that would
+       *        be generated are equal.
+       */
+      friend bool
+      operator==(const nakagami_distribution& __d1,
+		 const nakagami_distribution& __d2)
+      { return (__d1.param() == __d2.param()
+		&& __d1._M_gd == __d2._M_gd); }
+
+      /**
+       * @brief Inserts a %nakagami_distribution random number distribution
+       * @p __x into the output stream @p __os.
+       *
+       * @param __os An output stream.
+       * @param __x  A %nakagami_distribution random number distribution.
+       *
+       * @returns The output stream with the state of @p __x inserted or in
+       * an error state.
+       */
+      template<typename _RealType1, typename _CharT, typename _Traits>
+	friend std::basic_ostream<_CharT, _Traits>&
+	operator<<(std::basic_ostream<_CharT, _Traits>&,
+		   const nakagami_distribution<_RealType1>&);
+
+      /**
+       * @brief Extracts a %nakagami_distribution random number distribution
+       * @p __x from the input stream @p __is.
+       *
+       * @param __is An input stream.
+       * @param __x A %nakagami_distribution random number
+       *            generator engine.
+       *
+       * @returns The input stream with @p __x extracted or in an error state.
+       */
+      template<typename _RealType1, typename _CharT, typename _Traits>
+	friend std::basic_istream<_CharT, _Traits>&
+	operator>>(std::basic_istream<_CharT, _Traits>&,
+		   nakagami_distribution<_RealType1>&);
+
+    private:
+      template<typename _ForwardIterator,
+	       typename _UniformRandomNumberGenerator>
+	void
+	__generate_impl(_ForwardIterator __f, _ForwardIterator __t,
+			_UniformRandomNumberGenerator& __urng,
+			const param_type& __p);
+
+      param_type _M_param;
+
+      std::gamma_distribution<result_type> _M_gd;
+    };
+
+  /**
+   * @brief Return true if two Nakagami distributions are not equal.
+   */
+  template<typename _RealType>
+    inline bool
+    operator!=(const nakagami_distribution<_RealType>& __d1,
+	       const nakagami_distribution<_RealType>& __d2)
+    { return !(__d1 == __d2); }
+
 _GLIBCXX_END_NAMESPACE_VERSION
 } // namespace __gnu_cxx
 
diff --git a/libstdc++-v3/include/ext/random.tcc b/libstdc++-v3/include/ext/random.tcc
index 07001379415..3ee07cd6c1e 100644
--- a/libstdc++-v3/include/ext/random.tcc
+++ b/libstdc++-v3/include/ext/random.tcc
@@ -784,6 +784,70 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       return __is;
     }
 
+
+  template<typename _RealType>
+    template<typename _OutputIterator,
+	     typename _UniformRandomNumberGenerator>
+      void
+      nakagami_distribution<_RealType>::
+      __generate_impl(_OutputIterator __f, _OutputIterator __t,
+		      _UniformRandomNumberGenerator& __urng,
+		      const param_type& __p)
+      {
+	__glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator>)
+
+	typename std::gamma_distribution<result_type>::param_type
+	  __pg(__p.mu(), __p.omega() / __p.mu());
+	while (__f != __t)
+	  *__f++ = std::sqrt(this->_M_gd(__pg, __urng));
+      }
+
+  template<typename _RealType, typename _CharT, typename _Traits>
+    std::basic_ostream<_CharT, _Traits>&
+    operator<<(std::basic_ostream<_CharT, _Traits>& __os,
+	       const nakagami_distribution<_RealType>& __x)
+    {
+      typedef std::basic_ostream<_CharT, _Traits>  __ostream_type;
+      typedef typename __ostream_type::ios_base    __ios_base;
+
+      const typename __ios_base::fmtflags __flags = __os.flags();
+      const _CharT __fill = __os.fill();
+      const std::streamsize __precision = __os.precision();
+      const _CharT __space = __os.widen(' ');
+      __os.flags(__ios_base::scientific | __ios_base::left);
+      __os.fill(__space);
+      __os.precision(std::numeric_limits<_RealType>::max_digits10);
+
+      __os << __x.mu() << __space << __x.omega();
+      __os << __space << __x._M_gd;
+
+      __os.flags(__flags);
+      __os.fill(__fill);
+      __os.precision(__precision);
+      return __os;
+    }
+
+  template<typename _RealType, typename _CharT, typename _Traits>
+    std::basic_istream<_CharT, _Traits>&
+    operator>>(std::basic_istream<_CharT, _Traits>& __is,
+	       nakagami_distribution<_RealType>& __x)
+    {
+      typedef std::basic_istream<_CharT, _Traits>  __istream_type;
+      typedef typename __istream_type::ios_base    __ios_base;
+
+      const typename __ios_base::fmtflags __flags = __is.flags();
+      __is.flags(__ios_base::dec | __ios_base::skipws);
+
+      _RealType __mu, __omega;
+      __is >> __mu >> __omega;
+      __is >> __x._M_gd;
+      __x.param(typename nakagami_distribution<_RealType>::
+		param_type(__mu, __omega));
+
+      __is.flags(__flags);
+      return __is;
+    }
+
 _GLIBCXX_END_NAMESPACE_VERSION
 } // namespace
 
diff --git a/libstdc++-v3/testsuite/ext/random/nakagami_distribution/cons/default.cc b/libstdc++-v3/testsuite/ext/random/nakagami_distribution/cons/default.cc
new file mode 100644
index 00000000000..6edacc47f0d
--- /dev/null
+++ b/libstdc++-v3/testsuite/ext/random/nakagami_distribution/cons/default.cc
@@ -0,0 +1,47 @@
+// { dg-options "-std=c++0x" }
+// { dg-require-cstdint "" }
+//
+// 2012-09-18  Edward M. Smith-Rowland <3dw4rd@verizon.net>
+//
+// Copyright (C) 2012 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 26.4.8.3.* Class template nakagami_distribution [rand.dist.ext.nakagami]
+// 26.4.2.4 Concept RandomNumberDistribution [rand.concept.dist]
+
+#include <ext/random>
+#include <testsuite_hooks.h>
+
+void
+test01()
+{
+  bool test __attribute__((unused)) = true;
+
+  __gnu_cxx::nakagami_distribution<> u;
+  VERIFY( u.mu() == 1.0 );
+  VERIFY( u.omega() == 1.0 );
+  VERIFY( u.min() == 0.0 );
+  typedef __gnu_cxx::nakagami_distribution<>::result_type result_type;
+  VERIFY( u.max() == std::numeric_limits<result_type>::max() );
+}
+
+int
+main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/ext/random/nakagami_distribution/cons/parms.cc b/libstdc++-v3/testsuite/ext/random/nakagami_distribution/cons/parms.cc
new file mode 100644
index 00000000000..6fc23c8115e
--- /dev/null
+++ b/libstdc++-v3/testsuite/ext/random/nakagami_distribution/cons/parms.cc
@@ -0,0 +1,47 @@
+// { dg-options "-std=c++0x" }
+// { dg-require-cstdint "" }
+//
+// 2012-09-18  Edward M. Smith-Rowland <3dw4rd@verizon.net>
+//
+// Copyright (C) 2012 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 26.4.8.3.* Class template nakagami_distribution [rand.dist.ext.nakagami]
+// 26.4.2.4 Concept RandomNumberDistribution [rand.concept.dist]
+
+#include <ext/random>
+#include <testsuite_hooks.h>
+
+void
+test01()
+{
+  bool test __attribute__((unused)) = true;
+
+  __gnu_cxx::nakagami_distribution<> u(1.5, 3.0);
+  VERIFY( u.mu() == 1.5 );
+  VERIFY( u.omega() == 3.0 );
+  VERIFY( u.min() == 0.0 );
+  typedef __gnu_cxx::nakagami_distribution<>::result_type result_type;
+  VERIFY( u.max() == std::numeric_limits<result_type>::max() );
+}
+
+int
+main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/ext/random/nakagami_distribution/operators/equal.cc b/libstdc++-v3/testsuite/ext/random/nakagami_distribution/operators/equal.cc
new file mode 100644
index 00000000000..b26be72f3e1
--- /dev/null
+++ b/libstdc++-v3/testsuite/ext/random/nakagami_distribution/operators/equal.cc
@@ -0,0 +1,44 @@
+// { dg-options "-std=c++0x" }
+// { dg-require-cstdint "" }
+//
+// 2012-09-18  Edward M. Smith-Rowland  <3dw4rd@verizon.net>
+//
+// Copyright (C) 2012 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 26.5.8.4.5 Class template nakagami_distribution [rand.dist.ext.nakagami]
+
+#include <ext/random>
+#include <testsuite_hooks.h>
+
+void
+test01()
+{
+  bool test __attribute__((unused)) = true;
+
+  __gnu_cxx::nakagami_distribution<double> u(2.0, 3.0), v, w;
+
+  VERIFY( v == w );
+  VERIFY( !(u == v) );
+}
+
+int
+main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/ext/random/nakagami_distribution/operators/inequal.cc b/libstdc++-v3/testsuite/ext/random/nakagami_distribution/operators/inequal.cc
new file mode 100644
index 00000000000..345da3bdeaa
--- /dev/null
+++ b/libstdc++-v3/testsuite/ext/random/nakagami_distribution/operators/inequal.cc
@@ -0,0 +1,44 @@
+// { dg-options "-std=c++0x" }
+// { dg-require-cstdint "" }
+//
+// 2012-09-18  Edward M. Smith-Rowland  <3dw4rd@verizon.net>
+//
+// Copyright (C) 2012 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 26.5.8.4.5 Class template nakagami_distribution [rand.dist.ext.nakagami]
+
+#include <ext/random>
+#include <testsuite_hooks.h>
+
+void
+test01()
+{
+  bool test __attribute__((unused)) = true;
+
+  __gnu_cxx::nakagami_distribution<double> u(2.0, 3.0), v, w;
+
+  VERIFY( u != v );
+  VERIFY( !(v != w) );
+}
+
+int
+main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/ext/random/nakagami_distribution/operators/serialize.cc b/libstdc++-v3/testsuite/ext/random/nakagami_distribution/operators/serialize.cc
new file mode 100644
index 00000000000..49bb4d3c0cb
--- /dev/null
+++ b/libstdc++-v3/testsuite/ext/random/nakagami_distribution/operators/serialize.cc
@@ -0,0 +1,51 @@
+// { dg-options "-std=c++0x" }
+// { dg-require-cstdint "" }
+//
+// 2012-09-18  Edward M. Smith-Rowland  <3dw4rd@verizon.net>
+//
+// Copyright (C) 2012 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 26.4.8.3.* Class template nakagami_distribution [rand.dist.ext.nakagami]
+// 26.4.2.4 Concept RandomNumberDistribution [rand.concept.dist]
+
+#include <ext/random>
+#include <sstream>
+#include <testsuite_hooks.h>
+
+void
+test01()
+{
+  bool test __attribute__((unused)) = true;
+
+  std::stringstream str;
+  __gnu_cxx::nakagami_distribution<double> u(1.5, 3.0), v;
+  std::minstd_rand0 rng;
+
+  u(rng); // advance
+  str << u;
+
+  str >> v;
+  VERIFY( u == v );
+}
+
+int
+main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/ext/random/nakagami_distribution/requirements/explicit_instantiation/1.cc b/libstdc++-v3/testsuite/ext/random/nakagami_distribution/requirements/explicit_instantiation/1.cc
new file mode 100644
index 00000000000..30f011e3386
--- /dev/null
+++ b/libstdc++-v3/testsuite/ext/random/nakagami_distribution/requirements/explicit_instantiation/1.cc
@@ -0,0 +1,26 @@
+// { dg-do compile }
+// { dg-options "-std=c++11" }
+// { dg-require-cstdint "" }
+//
+// Copyright (C) 2012 Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <ext/random>
+
+template class __gnu_cxx::nakagami_distribution<float>;
+template class __gnu_cxx::nakagami_distribution<double>;
+template class __gnu_cxx::nakagami_distribution<long double>;
diff --git a/libstdc++-v3/testsuite/ext/random/nakagami_distribution/requirements/typedefs.cc b/libstdc++-v3/testsuite/ext/random/nakagami_distribution/requirements/typedefs.cc
new file mode 100644
index 00000000000..d17117e0d35
--- /dev/null
+++ b/libstdc++-v3/testsuite/ext/random/nakagami_distribution/requirements/typedefs.cc
@@ -0,0 +1,36 @@
+// { dg-do compile }
+// { dg-options "-std=c++0x" }
+// { dg-require-cstdint "" }
+//
+// 2012-09-18  Edward M. Smith-Rowland <3dw4rd@verizon.net>
+//
+// Copyright (C) 2012 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 26.4.8.3.* Class template nakagami_distribution [rand.dist.ext.nakagami]
+// 26.4.2.4 Concept RandomNumberDistribution [rand.concept.dist]
+
+#include <ext/random>
+
+void
+test01()
+{
+  typedef __gnu_cxx::nakagami_distribution<double> test_type;
+
+  typedef test_type::result_type result_type;
+  typedef test_type::param_type param_type;
+}