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// 26.4.8.5.2 Class template piecewise_constant_distribution 24// [rand.dist.samp.pconst] 25// 26.4.2.4 Concept RandomNumberDistribution [rand.concept.dist] 26 27#include <random> 28#include <cmath> 29#include <testsuite_hooks.h> 30 31struct cosine_distribution 32{ 33 cosine_distribution(double x0, double lambda) 34 : _M_x0(x0), _M_lambda(lambda) 35 { } 36 37 double 38 operator()(double x) 39 { 40 if (x - _M_x0 < -_M_lambda / 4) 41 return 0.0; 42 else if (x - _M_x0 > _M_lambda / 4) 43 return 0.0; 44 else 45 { 46 const double pi = 3.14159265358979323846; 47 return std::cos(2 * pi * (x - _M_x0) / _M_lambda); 48 } 49 } 50 51private: 52 double _M_x0; 53 double _M_lambda; 54}; 55 56void 57test01() 58{ 59 bool test __attribute__((unused)) = true; 60 61 cosine_distribution cd(1.5, 3.0); 62 std::piecewise_constant_distribution<> u({-10.0, -8.0, -6.0, -4.0, -2.0, 63 0.0, 2.0, 4.0, 6.0, 8.0, 10.0}, 64 cd); 65 std::vector<double> interval = u.intervals(); 66 std::vector<double> density = u.densities(); 67 VERIFY( interval.size() == 11 ); 68 VERIFY( density.size() == 10 ); 69} 70 71int main() 72{ 73 test01(); 74 return 0; 75} 76