eval_param.pass.cpp (2853B)
1 //===----------------------------------------------------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is dual licensed under the MIT and the University of Illinois Open 6 // Source Licenses. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // REQUIRES: long_tests 11 12 // <random> 13 14 // template<class RealType = double> 15 // class fisher_f_distribution 16 17 // template<class _URNG> result_type operator()(_URNG& g, const param_type& parm); 18 19 #include <random> 20 #include <cassert> 21 #include <vector> 22 #include <algorithm> 23 #include <cmath> 24 25 double fac(double x) 26 { 27 double r = 1; 28 for (; x > 1; --x) 29 r *= x; 30 return r; 31 } 32 33 double 34 I(double x, unsigned a, unsigned b) 35 { 36 double r = 0; 37 for (int j = a; static_cast<unsigned>(j) <= a+b-1; ++j) 38 r += fac(a+b-1)/(fac(j) * fac(a + b - 1 - j)) * std::pow(x, j) * 39 std::pow(1-x, a+b-1-j); 40 return r; 41 } 42 43 double 44 f(double x, double m, double n) 45 { 46 return I(m * x / (m*x + n), static_cast<unsigned>(m/2), static_cast<unsigned>(n/2)); 47 } 48 49 int main() 50 { 51 // Purposefully only testing even integral values of m and n (for now) 52 { 53 typedef std::fisher_f_distribution<> D; 54 typedef D::param_type P; 55 typedef std::mt19937 G; 56 G g; 57 D d(2, 4); 58 P p(4, 2); 59 const int N = 100000; 60 std::vector<D::result_type> u; 61 for (int i = 0; i < N; ++i) 62 { 63 D::result_type v = d(g, p); 64 assert(v >= 0); 65 u.push_back(v); 66 } 67 std::sort(u.begin(), u.end()); 68 for (int i = 0; i < N; ++i) 69 assert(std::abs(f(u[i], p.m(), p.n()) - double(i)/N) < .01); 70 } 71 { 72 typedef std::fisher_f_distribution<> D; 73 typedef D::param_type P; 74 typedef std::mt19937 G; 75 G g; 76 D d(4, 2); 77 P p(6, 8); 78 const int N = 100000; 79 std::vector<D::result_type> u; 80 for (int i = 0; i < N; ++i) 81 { 82 D::result_type v = d(g, p); 83 assert(v >= 0); 84 u.push_back(v); 85 } 86 std::sort(u.begin(), u.end()); 87 for (int i = 0; i < N; ++i) 88 assert(std::abs(f(u[i], p.m(), p.n()) - double(i)/N) < .01); 89 } 90 { 91 typedef std::fisher_f_distribution<> D; 92 typedef D::param_type P; 93 typedef std::mt19937 G; 94 G g; 95 D d(18, 20); 96 P p(16, 14); 97 const int N = 100000; 98 std::vector<D::result_type> u; 99 for (int i = 0; i < N; ++i) 100 { 101 D::result_type v = d(g, p); 102 assert(v >= 0); 103 u.push_back(v); 104 } 105 std::sort(u.begin(), u.end()); 106 for (int i = 0; i < N; ++i) 107 assert(std::abs(f(u[i], p.m(), p.n()) - double(i)/N) < .01); 108 } 109 }