1// { dg-options "-std=gnu++11" }
2// { dg-require-cstdint "" }
3//
4// 2008-12-03  Edward M. Smith-Rowland <3dw4rd@verizon.net>
5//
6// Copyright (C) 2008-2015 Free Software Foundation, Inc.
7//
8// This file is part of the GNU ISO C++ Library.  This library is free
9// software; you can redistribute it and/or modify it under the
10// terms of the GNU General Public License as published by the
11// Free Software Foundation; either version 3, or (at your option)
12// any later version.
13//
14// This library is distributed in the hope that it will be useful,
15// but WITHOUT ANY WARRANTY; without even the implied warranty of
16// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17// GNU General Public License for more details.
18//
19// You should have received a copy of the GNU General Public License along
20// with this library; see the file COPYING3.  If not see
21// <http://www.gnu.org/licenses/>.
22
23// 26.4.8.5.1 Class template discrete_distribution [rand.dist.samp.discrete]
24// 26.4.2.4 Concept RandomNumberDistribution [rand.concept.dist]
25
26#include <random>
27#include <cmath>
28#include <testsuite_hooks.h>
29
30struct cosine_distribution
31{
32    cosine_distribution(double x0, double lambda)
33    : _M_x0(x0), _M_lambda(lambda)
34    { }
35
36    double
37    operator()(double x)
38    {
39      if (x - _M_x0 < -_M_lambda / 4)
40        return 0.0;
41      else if (x - _M_x0 > _M_lambda / 4)
42        return 0.0;
43      else
44	{
45	  const double pi = 3.14159265358979323846;
46	  return std::cos(2 * pi * (x - _M_x0) / _M_lambda);
47	}
48    }
49
50private:
51    double _M_x0;
52    double _M_lambda;
53};
54
55void
56test01()
57{
58  bool test __attribute__((unused)) = true;
59
60  cosine_distribution cd(1.5, 3.0);
61  std::discrete_distribution<> u(21, -10.0, 10.0, cd);
62  std::vector<double> probablility = u.probabilities();
63  VERIFY( probablility.size() == 21 );
64}
65
66int main()
67{
68  test01();
69  return 0;
70}
71