Howard Hinnant | 5430540 | 2010-05-25 00:27:34 +0000 | [diff] [blame] | 1 | //===----------------------------------------------------------------------===// |
| 2 | // |
| 3 | // The LLVM Compiler Infrastructure |
| 4 | // |
Howard Hinnant | b64f8b0 | 2010-11-16 22:09:02 +0000 | [diff] [blame] | 5 | // This file is dual licensed under the MIT and the University of Illinois Open |
| 6 | // Source Licenses. See LICENSE.TXT for details. |
Howard Hinnant | 5430540 | 2010-05-25 00:27:34 +0000 | [diff] [blame] | 7 | // |
| 8 | //===----------------------------------------------------------------------===// |
Jonathan Roelofs | d9144e8 | 2014-12-11 18:35:36 +0000 | [diff] [blame] | 9 | // |
| 10 | // REQUIRES: long_tests |
Howard Hinnant | 5430540 | 2010-05-25 00:27:34 +0000 | [diff] [blame] | 11 | |
| 12 | // <random> |
| 13 | |
| 14 | // template<class RealType = double> |
| 15 | // class piecewise_linear_distribution |
| 16 | |
| 17 | // template<class _URNG> result_type operator()(_URNG& g); |
| 18 | |
| 19 | #include <iostream> |
| 20 | |
| 21 | #include <random> |
Howard Hinnant | 5430540 | 2010-05-25 00:27:34 +0000 | [diff] [blame] | 22 | #include <vector> |
| 23 | #include <iterator> |
| 24 | #include <numeric> |
| 25 | #include <cassert> |
| 26 | |
| 27 | template <class T> |
| 28 | inline |
| 29 | T |
| 30 | sqr(T x) |
| 31 | { |
| 32 | return x*x; |
| 33 | } |
| 34 | |
| 35 | double |
| 36 | f(double x, double a, double m, double b, double c) |
| 37 | { |
| 38 | return a + m*(sqr(x) - sqr(b))/2 + c*(x-b); |
| 39 | } |
| 40 | |
| 41 | int main() |
| 42 | { |
| 43 | { |
| 44 | typedef std::piecewise_linear_distribution<> D; |
| 45 | typedef D::param_type P; |
| 46 | typedef std::mt19937_64 G; |
| 47 | G g; |
| 48 | double b[] = {10, 14, 16, 17}; |
| 49 | double p[] = {0, 1, 1, 0}; |
| 50 | const size_t Np = sizeof(p) / sizeof(p[0]) - 1; |
| 51 | D d(b, b+Np+1, p); |
| 52 | const int N = 1000000; |
| 53 | std::vector<D::result_type> u; |
| 54 | for (int i = 0; i < N; ++i) |
| 55 | { |
| 56 | D::result_type v = d(g); |
| 57 | assert(d.min() <= v && v < d.max()); |
| 58 | u.push_back(v); |
| 59 | } |
| 60 | std::sort(u.begin(), u.end()); |
| 61 | int kp = -1; |
Dan Albert | 1d4a1ed | 2016-05-25 22:36:09 -0700 | [diff] [blame^] | 62 | double a; |
| 63 | double m; |
| 64 | double bk; |
| 65 | double c; |
Howard Hinnant | 5430540 | 2010-05-25 00:27:34 +0000 | [diff] [blame] | 66 | std::vector<double> areas(Np); |
| 67 | double S = 0; |
| 68 | for (int i = 0; i < areas.size(); ++i) |
| 69 | { |
| 70 | areas[i] = (p[i]+p[i+1])*(b[i+1]-b[i])/2; |
| 71 | S += areas[i]; |
| 72 | } |
| 73 | for (int i = 0; i < areas.size(); ++i) |
| 74 | areas[i] /= S; |
| 75 | for (int i = 0; i < Np+1; ++i) |
| 76 | p[i] /= S; |
| 77 | for (int i = 0; i < N; ++i) |
| 78 | { |
| 79 | int k = std::lower_bound(b, b+Np+1, u[i]) - b - 1; |
| 80 | if (k != kp) |
| 81 | { |
| 82 | a = 0; |
| 83 | for (int j = 0; j < k; ++j) |
| 84 | a += areas[j]; |
| 85 | m = (p[k+1] - p[k]) / (b[k+1] - b[k]); |
| 86 | bk = b[k]; |
| 87 | c = (b[k+1]*p[k] - b[k]*p[k+1]) / (b[k+1] - b[k]); |
| 88 | kp = k; |
| 89 | } |
| 90 | assert(std::abs(f(u[i], a, m, bk, c) - double(i)/N) < .001); |
| 91 | } |
| 92 | } |
| 93 | { |
| 94 | typedef std::piecewise_linear_distribution<> D; |
| 95 | typedef D::param_type P; |
| 96 | typedef std::mt19937_64 G; |
| 97 | G g; |
| 98 | double b[] = {10, 14, 16, 17}; |
| 99 | double p[] = {0, 0, 1, 0}; |
| 100 | const size_t Np = sizeof(p) / sizeof(p[0]) - 1; |
| 101 | D d(b, b+Np+1, p); |
| 102 | const int N = 1000000; |
| 103 | std::vector<D::result_type> u; |
| 104 | for (int i = 0; i < N; ++i) |
| 105 | { |
| 106 | D::result_type v = d(g); |
| 107 | assert(d.min() <= v && v < d.max()); |
| 108 | u.push_back(v); |
| 109 | } |
| 110 | std::sort(u.begin(), u.end()); |
| 111 | int kp = -1; |
Dan Albert | 1d4a1ed | 2016-05-25 22:36:09 -0700 | [diff] [blame^] | 112 | double a; |
| 113 | double m; |
| 114 | double bk; |
| 115 | double c; |
Howard Hinnant | 5430540 | 2010-05-25 00:27:34 +0000 | [diff] [blame] | 116 | std::vector<double> areas(Np); |
| 117 | double S = 0; |
| 118 | for (int i = 0; i < areas.size(); ++i) |
| 119 | { |
| 120 | areas[i] = (p[i]+p[i+1])*(b[i+1]-b[i])/2; |
| 121 | S += areas[i]; |
| 122 | } |
| 123 | for (int i = 0; i < areas.size(); ++i) |
| 124 | areas[i] /= S; |
| 125 | for (int i = 0; i < Np+1; ++i) |
| 126 | p[i] /= S; |
| 127 | for (int i = 0; i < N; ++i) |
| 128 | { |
| 129 | int k = std::lower_bound(b, b+Np+1, u[i]) - b - 1; |
| 130 | if (k != kp) |
| 131 | { |
| 132 | a = 0; |
| 133 | for (int j = 0; j < k; ++j) |
| 134 | a += areas[j]; |
| 135 | m = (p[k+1] - p[k]) / (b[k+1] - b[k]); |
| 136 | bk = b[k]; |
| 137 | c = (b[k+1]*p[k] - b[k]*p[k+1]) / (b[k+1] - b[k]); |
| 138 | kp = k; |
| 139 | } |
| 140 | assert(std::abs(f(u[i], a, m, bk, c) - double(i)/N) < .001); |
| 141 | } |
| 142 | } |
| 143 | { |
| 144 | typedef std::piecewise_linear_distribution<> D; |
| 145 | typedef D::param_type P; |
| 146 | typedef std::mt19937_64 G; |
| 147 | G g; |
| 148 | double b[] = {10, 14, 16, 17}; |
| 149 | double p[] = {1, 0, 0, 0}; |
| 150 | const size_t Np = sizeof(p) / sizeof(p[0]) - 1; |
| 151 | D d(b, b+Np+1, p); |
| 152 | const int N = 1000000; |
| 153 | std::vector<D::result_type> u; |
| 154 | for (int i = 0; i < N; ++i) |
| 155 | { |
| 156 | D::result_type v = d(g); |
| 157 | assert(d.min() <= v && v < d.max()); |
| 158 | u.push_back(v); |
| 159 | } |
| 160 | std::sort(u.begin(), u.end()); |
| 161 | int kp = -1; |
Dan Albert | 1d4a1ed | 2016-05-25 22:36:09 -0700 | [diff] [blame^] | 162 | double a; |
| 163 | double m; |
| 164 | double bk; |
| 165 | double c; |
Howard Hinnant | 5430540 | 2010-05-25 00:27:34 +0000 | [diff] [blame] | 166 | std::vector<double> areas(Np); |
| 167 | double S = 0; |
| 168 | for (int i = 0; i < areas.size(); ++i) |
| 169 | { |
| 170 | areas[i] = (p[i]+p[i+1])*(b[i+1]-b[i])/2; |
| 171 | S += areas[i]; |
| 172 | } |
| 173 | for (int i = 0; i < areas.size(); ++i) |
| 174 | areas[i] /= S; |
| 175 | for (int i = 0; i < Np+1; ++i) |
| 176 | p[i] /= S; |
| 177 | for (int i = 0; i < N; ++i) |
| 178 | { |
| 179 | int k = std::lower_bound(b, b+Np+1, u[i]) - b - 1; |
| 180 | if (k != kp) |
| 181 | { |
| 182 | a = 0; |
| 183 | for (int j = 0; j < k; ++j) |
| 184 | a += areas[j]; |
| 185 | m = (p[k+1] - p[k]) / (b[k+1] - b[k]); |
| 186 | bk = b[k]; |
| 187 | c = (b[k+1]*p[k] - b[k]*p[k+1]) / (b[k+1] - b[k]); |
| 188 | kp = k; |
| 189 | } |
| 190 | assert(std::abs(f(u[i], a, m, bk, c) - double(i)/N) < .001); |
| 191 | } |
| 192 | } |
| 193 | { |
| 194 | typedef std::piecewise_linear_distribution<> D; |
| 195 | typedef D::param_type P; |
| 196 | typedef std::mt19937_64 G; |
| 197 | G g; |
| 198 | double b[] = {10, 14, 16}; |
| 199 | double p[] = {0, 1, 0}; |
| 200 | const size_t Np = sizeof(p) / sizeof(p[0]) - 1; |
| 201 | D d(b, b+Np+1, p); |
| 202 | const int N = 1000000; |
| 203 | std::vector<D::result_type> u; |
| 204 | for (int i = 0; i < N; ++i) |
| 205 | { |
| 206 | D::result_type v = d(g); |
| 207 | assert(d.min() <= v && v < d.max()); |
| 208 | u.push_back(v); |
| 209 | } |
| 210 | std::sort(u.begin(), u.end()); |
| 211 | int kp = -1; |
Dan Albert | 1d4a1ed | 2016-05-25 22:36:09 -0700 | [diff] [blame^] | 212 | double a; |
| 213 | double m; |
| 214 | double bk; |
| 215 | double c; |
Howard Hinnant | 5430540 | 2010-05-25 00:27:34 +0000 | [diff] [blame] | 216 | std::vector<double> areas(Np); |
| 217 | double S = 0; |
| 218 | for (int i = 0; i < areas.size(); ++i) |
| 219 | { |
| 220 | areas[i] = (p[i]+p[i+1])*(b[i+1]-b[i])/2; |
| 221 | S += areas[i]; |
| 222 | } |
| 223 | for (int i = 0; i < areas.size(); ++i) |
| 224 | areas[i] /= S; |
| 225 | for (int i = 0; i < Np+1; ++i) |
| 226 | p[i] /= S; |
| 227 | for (int i = 0; i < N; ++i) |
| 228 | { |
| 229 | int k = std::lower_bound(b, b+Np+1, u[i]) - b - 1; |
| 230 | if (k != kp) |
| 231 | { |
| 232 | a = 0; |
| 233 | for (int j = 0; j < k; ++j) |
| 234 | a += areas[j]; |
| 235 | m = (p[k+1] - p[k]) / (b[k+1] - b[k]); |
| 236 | bk = b[k]; |
| 237 | c = (b[k+1]*p[k] - b[k]*p[k+1]) / (b[k+1] - b[k]); |
| 238 | kp = k; |
| 239 | } |
| 240 | assert(std::abs(f(u[i], a, m, bk, c) - double(i)/N) < .001); |
| 241 | } |
| 242 | } |
| 243 | { |
| 244 | typedef std::piecewise_linear_distribution<> D; |
| 245 | typedef D::param_type P; |
| 246 | typedef std::mt19937_64 G; |
| 247 | G g; |
| 248 | double b[] = {10, 14}; |
| 249 | double p[] = {1, 1}; |
| 250 | const size_t Np = sizeof(p) / sizeof(p[0]) - 1; |
| 251 | D d(b, b+Np+1, p); |
| 252 | const int N = 1000000; |
| 253 | std::vector<D::result_type> u; |
| 254 | for (int i = 0; i < N; ++i) |
| 255 | { |
| 256 | D::result_type v = d(g); |
| 257 | assert(d.min() <= v && v < d.max()); |
| 258 | u.push_back(v); |
| 259 | } |
| 260 | std::sort(u.begin(), u.end()); |
| 261 | int kp = -1; |
Dan Albert | 1d4a1ed | 2016-05-25 22:36:09 -0700 | [diff] [blame^] | 262 | double a; |
| 263 | double m; |
| 264 | double bk; |
| 265 | double c; |
Howard Hinnant | 5430540 | 2010-05-25 00:27:34 +0000 | [diff] [blame] | 266 | std::vector<double> areas(Np); |
| 267 | double S = 0; |
| 268 | for (int i = 0; i < areas.size(); ++i) |
| 269 | { |
| 270 | areas[i] = (p[i]+p[i+1])*(b[i+1]-b[i])/2; |
| 271 | S += areas[i]; |
| 272 | } |
| 273 | for (int i = 0; i < areas.size(); ++i) |
| 274 | areas[i] /= S; |
| 275 | for (int i = 0; i < Np+1; ++i) |
| 276 | p[i] /= S; |
| 277 | for (int i = 0; i < N; ++i) |
| 278 | { |
| 279 | int k = std::lower_bound(b, b+Np+1, u[i]) - b - 1; |
| 280 | if (k != kp) |
| 281 | { |
| 282 | a = 0; |
| 283 | for (int j = 0; j < k; ++j) |
| 284 | a += areas[j]; |
| 285 | m = (p[k+1] - p[k]) / (b[k+1] - b[k]); |
| 286 | bk = b[k]; |
| 287 | c = (b[k+1]*p[k] - b[k]*p[k+1]) / (b[k+1] - b[k]); |
| 288 | kp = k; |
| 289 | } |
| 290 | assert(std::abs(f(u[i], a, m, bk, c) - double(i)/N) < .001); |
| 291 | } |
| 292 | } |
| 293 | { |
| 294 | typedef std::piecewise_linear_distribution<> D; |
| 295 | typedef D::param_type P; |
| 296 | typedef std::mt19937_64 G; |
| 297 | G g; |
| 298 | double b[] = {10, 14, 16, 17}; |
| 299 | double p[] = {25, 62.5, 12.5, 0}; |
| 300 | const size_t Np = sizeof(p) / sizeof(p[0]) - 1; |
| 301 | D d(b, b+Np+1, p); |
| 302 | const int N = 1000000; |
| 303 | std::vector<D::result_type> u; |
| 304 | for (int i = 0; i < N; ++i) |
| 305 | { |
| 306 | D::result_type v = d(g); |
| 307 | assert(d.min() <= v && v < d.max()); |
| 308 | u.push_back(v); |
| 309 | } |
| 310 | std::sort(u.begin(), u.end()); |
| 311 | int kp = -1; |
Dan Albert | 1d4a1ed | 2016-05-25 22:36:09 -0700 | [diff] [blame^] | 312 | double a; |
| 313 | double m; |
| 314 | double bk; |
| 315 | double c; |
Howard Hinnant | 5430540 | 2010-05-25 00:27:34 +0000 | [diff] [blame] | 316 | std::vector<double> areas(Np); |
| 317 | double S = 0; |
| 318 | for (int i = 0; i < areas.size(); ++i) |
| 319 | { |
| 320 | areas[i] = (p[i]+p[i+1])*(b[i+1]-b[i])/2; |
| 321 | S += areas[i]; |
| 322 | } |
| 323 | for (int i = 0; i < areas.size(); ++i) |
| 324 | areas[i] /= S; |
| 325 | for (int i = 0; i < Np+1; ++i) |
| 326 | p[i] /= S; |
| 327 | for (int i = 0; i < N; ++i) |
| 328 | { |
| 329 | int k = std::lower_bound(b, b+Np+1, u[i]) - b - 1; |
| 330 | if (k != kp) |
| 331 | { |
| 332 | a = 0; |
| 333 | for (int j = 0; j < k; ++j) |
| 334 | a += areas[j]; |
| 335 | m = (p[k+1] - p[k]) / (b[k+1] - b[k]); |
| 336 | bk = b[k]; |
| 337 | c = (b[k+1]*p[k] - b[k]*p[k+1]) / (b[k+1] - b[k]); |
| 338 | kp = k; |
| 339 | } |
| 340 | assert(std::abs(f(u[i], a, m, bk, c) - double(i)/N) < .001); |
| 341 | } |
| 342 | } |
| 343 | } |