| //===----------------------------------------------------------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| // <random> |
| |
| // template<class IntType = int> |
| // class discrete_distribution |
| |
| // template<class _URNG> result_type operator()(_URNG& g, const param_type& parm); |
| |
| #include <random> |
| #include <vector> |
| #include <cassert> |
| |
| int main() |
| { |
| { |
| typedef std::discrete_distribution<> D; |
| typedef D::param_type P; |
| typedef std::minstd_rand G; |
| G g; |
| D d; |
| double p0[] = {.3, .1, .6}; |
| P p(p0, p0+3); |
| const int N = 10000000; |
| std::vector<D::result_type> u(3); |
| for (int i = 0; i < N; ++i) |
| { |
| D::result_type v = d(g, p); |
| assert(0 <= v && v <= 2); |
| u[v]++; |
| } |
| std::vector<double> prob = p.probabilities(); |
| for (int i = 0; i <= 2; ++i) |
| assert(std::abs((double)u[i]/N - prob[i]) / prob[i] < 0.001); |
| } |
| } |