1 // { dg-options "-std=c++0x" } 2 // { dg-require-cstdint "" } 3 // 4 // 2008-12-03 Edward M. Smith-Rowland <3dw4rd@verizon.net> 5 // 6 // Copyright (C) 2008-2014 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 // 26.4.8.5.3 Class template piecewise_linear_distribution 24 // [rand.dist.samp.plinear] 25 // 26.4.2.4 Concept RandomNumberDistribution [rand.concept.dist] 26 27 #include <random> 28 #include <cmath> 29 #include <testsuite_hooks.h> 30 31 struct cosine_distribution 32 { cosine_distributioncosine_distribution33 cosine_distribution(double x0, double lambda) 34 : _M_x0(x0), _M_lambda(lambda) 35 { } 36 37 double operator ()cosine_distribution38 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 51 private: 52 double _M_x0; 53 double _M_lambda; 54 }; 55 56 void test01()57test01() 58 { 59 bool test __attribute__((unused)) = true; 60 61 cosine_distribution cd(1.5, 3.0); 62 std::piecewise_linear_distribution<> u(21, -10.0, 10.0, cd); 63 std::vector<double> interval = u.intervals(); 64 std::vector<double> density = u.densities(); 65 VERIFY( interval.size() == 22 ); 66 VERIFY( density.size() == 22 ); 67 } 68 main()69int main() 70 { 71 test01(); 72 return 0; 73 } 74