erf.hpp 57 KB

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  1. // (C) Copyright John Maddock 2006.
  2. // (C) Copyright Matt Borland 2024.
  3. // Use, modification and distribution are subject to the
  4. // Boost Software License, Version 1.0. (See accompanying file
  5. // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
  6. #ifndef BOOST_MATH_SPECIAL_ERF_HPP
  7. #define BOOST_MATH_SPECIAL_ERF_HPP
  8. #ifdef _MSC_VER
  9. #pragma once
  10. #endif
  11. #include <boost/math/tools/config.hpp>
  12. #ifndef BOOST_MATH_HAS_NVRTC
  13. #include <boost/math/special_functions/math_fwd.hpp>
  14. #include <boost/math/special_functions/gamma.hpp>
  15. #include <boost/math/tools/roots.hpp>
  16. #include <boost/math/policies/error_handling.hpp>
  17. #include <boost/math/tools/big_constant.hpp>
  18. #if defined(__GNUC__) && defined(BOOST_MATH_USE_FLOAT128)
  19. //
  20. // This is the only way we can avoid
  21. // warning: non-standard suffix on floating constant [-Wpedantic]
  22. // when building with -Wall -pedantic. Neither __extension__
  23. // nor #pragma diagnostic ignored work :(
  24. //
  25. #pragma GCC system_header
  26. #endif
  27. namespace boost{ namespace math{
  28. namespace detail
  29. {
  30. //
  31. // Asymptotic series for large z:
  32. //
  33. template <class T>
  34. struct erf_asympt_series_t
  35. {
  36. // LCOV_EXCL_START multiprecision case only, excluded from coverage analysis
  37. BOOST_MATH_GPU_ENABLED erf_asympt_series_t(T z) : xx(2 * -z * z), tk(1)
  38. {
  39. BOOST_MATH_STD_USING
  40. result = -exp(-z * z) / sqrt(boost::math::constants::pi<T>());
  41. result /= z;
  42. }
  43. typedef T result_type;
  44. BOOST_MATH_GPU_ENABLED T operator()()
  45. {
  46. BOOST_MATH_STD_USING
  47. T r = result;
  48. result *= tk / xx;
  49. tk += 2;
  50. if( fabs(r) < fabs(result))
  51. result = 0;
  52. return r;
  53. }
  54. // LCOV_EXCL_STOP
  55. private:
  56. T result;
  57. T xx;
  58. int tk;
  59. };
  60. //
  61. // How large z has to be in order to ensure that the series converges:
  62. //
  63. template <class T>
  64. BOOST_MATH_GPU_ENABLED inline float erf_asymptotic_limit_N(const T&)
  65. {
  66. return (std::numeric_limits<float>::max)();
  67. }
  68. BOOST_MATH_GPU_ENABLED inline float erf_asymptotic_limit_N(const std::integral_constant<int, 24>&)
  69. {
  70. return 2.8F;
  71. }
  72. BOOST_MATH_GPU_ENABLED inline float erf_asymptotic_limit_N(const std::integral_constant<int, 53>&)
  73. {
  74. return 4.3F;
  75. }
  76. BOOST_MATH_GPU_ENABLED inline float erf_asymptotic_limit_N(const std::integral_constant<int, 64>&)
  77. {
  78. return 4.8F;
  79. }
  80. BOOST_MATH_GPU_ENABLED inline float erf_asymptotic_limit_N(const std::integral_constant<int, 106>&)
  81. {
  82. return 6.5F;
  83. }
  84. BOOST_MATH_GPU_ENABLED inline float erf_asymptotic_limit_N(const std::integral_constant<int, 113>&)
  85. {
  86. return 6.8F;
  87. }
  88. template <class T, class Policy>
  89. BOOST_MATH_GPU_ENABLED inline T erf_asymptotic_limit()
  90. {
  91. typedef typename policies::precision<T, Policy>::type precision_type;
  92. typedef std::integral_constant<int,
  93. precision_type::value <= 0 ? 0 :
  94. precision_type::value <= 24 ? 24 :
  95. precision_type::value <= 53 ? 53 :
  96. precision_type::value <= 64 ? 64 :
  97. precision_type::value <= 113 ? 113 : 0
  98. > tag_type;
  99. return erf_asymptotic_limit_N(tag_type());
  100. }
  101. // LCOV_EXCL_START multiprecision case only, excluded from coverage analysis
  102. template <class T>
  103. struct erf_series_near_zero
  104. {
  105. typedef T result_type;
  106. T term;
  107. T zz;
  108. int k;
  109. erf_series_near_zero(const T& z) : term(z), zz(-z * z), k(0) {}
  110. T operator()()
  111. {
  112. T result = term / (2 * k + 1);
  113. term *= zz / ++k;
  114. return result;
  115. }
  116. };
  117. template <class T, class Policy>
  118. T erf_series_near_zero_sum(const T& x, const Policy& pol)
  119. {
  120. //
  121. // We need Kahan summation here, otherwise the errors grow fairly quickly.
  122. // This method is *much* faster than the alternatives even so.
  123. //
  124. erf_series_near_zero<T> sum(x);
  125. std::uintmax_t max_iter = policies::get_max_series_iterations<Policy>();
  126. T result = constants::two_div_root_pi<T>() * tools::kahan_sum_series(sum, tools::digits<T>(), max_iter);
  127. policies::check_series_iterations<T>("boost::math::erf<%1%>(%1%, %1%)", max_iter, pol);
  128. return result;
  129. }
  130. template <class T, class Policy, class Tag>
  131. T erf_imp(T z, bool invert, const Policy& pol, const Tag& t)
  132. {
  133. BOOST_MATH_STD_USING
  134. BOOST_MATH_INSTRUMENT_CODE("Generic erf_imp called");
  135. if ((boost::math::isnan)(z))
  136. return policies::raise_domain_error("boost::math::erf<%1%>(%1%)", "Expected a finite argument but got %1%", z, pol);
  137. if (fabs(z) < tools::root_epsilon<T>())
  138. {
  139. // Series[Erf[x], {x, 0, 4}]
  140. // Series[Erfc[x], {x, 0, 4}]
  141. const T term2 { z * 2 / constants::root_pi<T>() };
  142. return invert ? 1 - term2 : term2;
  143. }
  144. const bool signbit_result = ((boost::math::signbit)(z) != 0);
  145. if (signbit_result)
  146. {
  147. if(!invert)
  148. return -erf_imp(T(-z), invert, pol, t);
  149. else
  150. return 1 + erf_imp(T(-z), false, pol, t);
  151. }
  152. T result;
  153. if(!invert && (z > detail::erf_asymptotic_limit<T, Policy>()))
  154. {
  155. detail::erf_asympt_series_t<T> s(z);
  156. std::uintmax_t max_iter = policies::get_max_series_iterations<Policy>();
  157. result = boost::math::tools::sum_series(s, policies::get_epsilon<T, Policy>(), max_iter, 1);
  158. policies::check_series_iterations<T>("boost::math::erf<%1%>(%1%, %1%)", max_iter, pol);
  159. }
  160. else
  161. {
  162. const T z_sq { z * z };
  163. if(z < 1.3f)
  164. {
  165. // Compute P:
  166. // This is actually good for z p to 2 or so, but the cutoff given seems
  167. // to be the best compromise. Regarding performance, this is way quicker than anything else...
  168. result = erf_series_near_zero_sum(z, pol);
  169. }
  170. else if(z_sq > 1 / tools::epsilon<T>())
  171. {
  172. // http://functions.wolfram.com/06.27.06.0006.02
  173. invert = !invert;
  174. result = exp(-z_sq) / (constants::root_pi<T>() * z);
  175. }
  176. else
  177. {
  178. // Compute Q:
  179. invert = !invert;
  180. result = z * exp(-z_sq);
  181. result /= boost::math::constants::root_pi<T>();
  182. result *= upper_gamma_fraction(T(0.5f), z_sq, policies::get_epsilon<T, Policy>());
  183. }
  184. }
  185. return ((!invert) ? result : 1 - result);
  186. }
  187. // LCOV_EXCL_STOP
  188. template <class T, class Policy>
  189. BOOST_MATH_GPU_ENABLED T erf_imp(T z, bool invert, const Policy& pol, const std::integral_constant<int, 53>&)
  190. {
  191. BOOST_MATH_STD_USING
  192. BOOST_MATH_INSTRUMENT_CODE("53-bit precision erf_imp called");
  193. if ((boost::math::isnan)(z))
  194. return policies::raise_domain_error("boost::math::erf<%1%>(%1%)", "Expected a finite argument but got %1%", z, pol);
  195. int prefix_multiplier = 1;
  196. int prefix_adder = 0;
  197. if(z < 0)
  198. {
  199. // Recursion is logically simpler here, but confuses static analyzers that need to be
  200. // able to calculate the maximimum program stack size at compile time (ie CUDA).
  201. z = -z;
  202. if(!invert)
  203. {
  204. prefix_multiplier = -1;
  205. // return -erf_imp(T(-z), invert, pol, t);
  206. }
  207. else if (z > T(0.5))
  208. {
  209. prefix_adder = 2;
  210. prefix_multiplier = -1;
  211. // return 2 - erf_imp(T(-z), invert, pol, t);
  212. }
  213. else
  214. {
  215. invert = false;
  216. prefix_adder = 1;
  217. // return 1 + erf_imp(T(-z), false, pol, t);
  218. }
  219. }
  220. T result;
  221. //
  222. // Big bunch of selection statements now to pick
  223. // which implementation to use,
  224. // try to put most likely options first:
  225. //
  226. if(z < T(0.5))
  227. {
  228. //
  229. // We're going to calculate erf:
  230. //
  231. if(z < T(1e-10))
  232. {
  233. if(z == 0)
  234. {
  235. result = T(0);
  236. }
  237. else
  238. {
  239. BOOST_MATH_STATIC_LOCAL_VARIABLE const T c = BOOST_MATH_BIG_CONSTANT(T, 53, 0.003379167095512573896158903121545171688); // LCOV_EXCL_LINE
  240. result = static_cast<T>(z * 1.125f + z * c);
  241. }
  242. }
  243. else
  244. {
  245. // Maximum Deviation Found: 1.561e-17
  246. // Expected Error Term: 1.561e-17
  247. // Maximum Relative Change in Control Points: 1.155e-04
  248. // Max Error found at double precision = 2.961182e-17
  249. // LCOV_EXCL_START
  250. BOOST_MATH_STATIC_LOCAL_VARIABLE const T Y = 1.044948577880859375f;
  251. BOOST_MATH_STATIC const T P[] = {
  252. BOOST_MATH_BIG_CONSTANT(T, 53, 0.0834305892146531832907),
  253. BOOST_MATH_BIG_CONSTANT(T, 53, -0.338165134459360935041),
  254. BOOST_MATH_BIG_CONSTANT(T, 53, -0.0509990735146777432841),
  255. BOOST_MATH_BIG_CONSTANT(T, 53, -0.00772758345802133288487),
  256. BOOST_MATH_BIG_CONSTANT(T, 53, -0.000322780120964605683831),
  257. };
  258. BOOST_MATH_STATIC const T Q[] = {
  259. BOOST_MATH_BIG_CONSTANT(T, 53, 1.0),
  260. BOOST_MATH_BIG_CONSTANT(T, 53, 0.455004033050794024546),
  261. BOOST_MATH_BIG_CONSTANT(T, 53, 0.0875222600142252549554),
  262. BOOST_MATH_BIG_CONSTANT(T, 53, 0.00858571925074406212772),
  263. BOOST_MATH_BIG_CONSTANT(T, 53, 0.000370900071787748000569),
  264. };
  265. // LCOV_EXCL_STOP
  266. T zz = z * z;
  267. result = z * (Y + tools::evaluate_polynomial(P, zz) / tools::evaluate_polynomial(Q, zz));
  268. }
  269. }
  270. else if(invert ? (z < 28) : (z < 5.93f))
  271. {
  272. //
  273. // We'll be calculating erfc:
  274. //
  275. invert = !invert;
  276. if(z < 1.5f)
  277. {
  278. // Maximum Deviation Found: 3.702e-17
  279. // Expected Error Term: 3.702e-17
  280. // Maximum Relative Change in Control Points: 2.845e-04
  281. // Max Error found at double precision = 4.841816e-17
  282. // LCOV_EXCL_START
  283. BOOST_MATH_STATIC_LOCAL_VARIABLE const T Y = 0.405935764312744140625f;
  284. BOOST_MATH_STATIC const T P[] = {
  285. BOOST_MATH_BIG_CONSTANT(T, 53, -0.098090592216281240205),
  286. BOOST_MATH_BIG_CONSTANT(T, 53, 0.178114665841120341155),
  287. BOOST_MATH_BIG_CONSTANT(T, 53, 0.191003695796775433986),
  288. BOOST_MATH_BIG_CONSTANT(T, 53, 0.0888900368967884466578),
  289. BOOST_MATH_BIG_CONSTANT(T, 53, 0.0195049001251218801359),
  290. BOOST_MATH_BIG_CONSTANT(T, 53, 0.00180424538297014223957),
  291. };
  292. BOOST_MATH_STATIC const T Q[] = {
  293. BOOST_MATH_BIG_CONSTANT(T, 53, 1.0),
  294. BOOST_MATH_BIG_CONSTANT(T, 53, 1.84759070983002217845),
  295. BOOST_MATH_BIG_CONSTANT(T, 53, 1.42628004845511324508),
  296. BOOST_MATH_BIG_CONSTANT(T, 53, 0.578052804889902404909),
  297. BOOST_MATH_BIG_CONSTANT(T, 53, 0.12385097467900864233),
  298. BOOST_MATH_BIG_CONSTANT(T, 53, 0.0113385233577001411017),
  299. BOOST_MATH_BIG_CONSTANT(T, 53, 0.337511472483094676155e-5),
  300. };
  301. // LCOV_EXCL_STOP
  302. BOOST_MATH_INSTRUMENT_VARIABLE(Y);
  303. BOOST_MATH_INSTRUMENT_VARIABLE(P[0]);
  304. BOOST_MATH_INSTRUMENT_VARIABLE(Q[0]);
  305. BOOST_MATH_INSTRUMENT_VARIABLE(z);
  306. result = Y + tools::evaluate_polynomial(P, T(z - T(0.5))) / tools::evaluate_polynomial(Q, T(z - T(0.5)));
  307. BOOST_MATH_INSTRUMENT_VARIABLE(result);
  308. result *= exp(-z * z) / z;
  309. BOOST_MATH_INSTRUMENT_VARIABLE(result);
  310. }
  311. else if(z < 2.5f)
  312. {
  313. // Max Error found at double precision = 6.599585e-18
  314. // Maximum Deviation Found: 3.909e-18
  315. // Expected Error Term: 3.909e-18
  316. // Maximum Relative Change in Control Points: 9.886e-05
  317. // LCOV_EXCL_START
  318. BOOST_MATH_STATIC_LOCAL_VARIABLE const T Y = 0.50672817230224609375f;
  319. BOOST_MATH_STATIC const T P[] = {
  320. BOOST_MATH_BIG_CONSTANT(T, 53, -0.0243500476207698441272),
  321. BOOST_MATH_BIG_CONSTANT(T, 53, 0.0386540375035707201728),
  322. BOOST_MATH_BIG_CONSTANT(T, 53, 0.04394818964209516296),
  323. BOOST_MATH_BIG_CONSTANT(T, 53, 0.0175679436311802092299),
  324. BOOST_MATH_BIG_CONSTANT(T, 53, 0.00323962406290842133584),
  325. BOOST_MATH_BIG_CONSTANT(T, 53, 0.000235839115596880717416),
  326. };
  327. BOOST_MATH_STATIC const T Q[] = {
  328. BOOST_MATH_BIG_CONSTANT(T, 53, 1.0),
  329. BOOST_MATH_BIG_CONSTANT(T, 53, 1.53991494948552447182),
  330. BOOST_MATH_BIG_CONSTANT(T, 53, 0.982403709157920235114),
  331. BOOST_MATH_BIG_CONSTANT(T, 53, 0.325732924782444448493),
  332. BOOST_MATH_BIG_CONSTANT(T, 53, 0.0563921837420478160373),
  333. BOOST_MATH_BIG_CONSTANT(T, 53, 0.00410369723978904575884),
  334. };
  335. // LCOV_EXCL_STOP
  336. result = Y + tools::evaluate_polynomial(P, T(z - T(1.5))) / tools::evaluate_polynomial(Q, z - T(1.5));
  337. T hi, lo;
  338. int expon;
  339. hi = floor(ldexp(frexp(z, &expon), 26));
  340. hi = ldexp(hi, expon - 26);
  341. lo = z - hi;
  342. T sq = z * z;
  343. T err_sqr = ((hi * hi - sq) + 2 * hi * lo) + lo * lo;
  344. result *= exp(-sq) * exp(-err_sqr) / z;
  345. }
  346. else if(z < 4.5f)
  347. {
  348. // Maximum Deviation Found: 1.512e-17
  349. // Expected Error Term: 1.512e-17
  350. // Maximum Relative Change in Control Points: 2.222e-04
  351. // Max Error found at double precision = 2.062515e-17
  352. // LCOV_EXCL_START
  353. BOOST_MATH_STATIC_LOCAL_VARIABLE const T Y = 0.5405750274658203125f;
  354. BOOST_MATH_STATIC const T P[] = {
  355. BOOST_MATH_BIG_CONSTANT(T, 53, 0.00295276716530971662634),
  356. BOOST_MATH_BIG_CONSTANT(T, 53, 0.0137384425896355332126),
  357. BOOST_MATH_BIG_CONSTANT(T, 53, 0.00840807615555585383007),
  358. BOOST_MATH_BIG_CONSTANT(T, 53, 0.00212825620914618649141),
  359. BOOST_MATH_BIG_CONSTANT(T, 53, 0.000250269961544794627958),
  360. BOOST_MATH_BIG_CONSTANT(T, 53, 0.113212406648847561139e-4),
  361. };
  362. BOOST_MATH_STATIC const T Q[] = {
  363. BOOST_MATH_BIG_CONSTANT(T, 53, 1.0),
  364. BOOST_MATH_BIG_CONSTANT(T, 53, 1.04217814166938418171),
  365. BOOST_MATH_BIG_CONSTANT(T, 53, 0.442597659481563127003),
  366. BOOST_MATH_BIG_CONSTANT(T, 53, 0.0958492726301061423444),
  367. BOOST_MATH_BIG_CONSTANT(T, 53, 0.0105982906484876531489),
  368. BOOST_MATH_BIG_CONSTANT(T, 53, 0.000479411269521714493907),
  369. };
  370. // LCOV_EXCL_STOP
  371. result = Y + tools::evaluate_polynomial(P, T(z - T(3.5))) / tools::evaluate_polynomial(Q, z - T(3.5));
  372. T hi, lo;
  373. int expon;
  374. hi = floor(ldexp(frexp(z, &expon), 26));
  375. hi = ldexp(hi, expon - 26);
  376. lo = z - hi;
  377. T sq = z * z;
  378. T err_sqr = ((hi * hi - sq) + 2 * hi * lo) + lo * lo;
  379. result *= exp(-sq) * exp(-err_sqr) / z;
  380. }
  381. else
  382. {
  383. // Max Error found at double precision = 2.997958e-17
  384. // Maximum Deviation Found: 2.860e-17
  385. // Expected Error Term: 2.859e-17
  386. // Maximum Relative Change in Control Points: 1.357e-05
  387. // LCOV_EXCL_START
  388. BOOST_MATH_STATIC_LOCAL_VARIABLE const T Y = 0.5579090118408203125f;
  389. BOOST_MATH_STATIC const T P[] = {
  390. BOOST_MATH_BIG_CONSTANT(T, 53, 0.00628057170626964891937),
  391. BOOST_MATH_BIG_CONSTANT(T, 53, 0.0175389834052493308818),
  392. BOOST_MATH_BIG_CONSTANT(T, 53, -0.212652252872804219852),
  393. BOOST_MATH_BIG_CONSTANT(T, 53, -0.687717681153649930619),
  394. BOOST_MATH_BIG_CONSTANT(T, 53, -2.5518551727311523996),
  395. BOOST_MATH_BIG_CONSTANT(T, 53, -3.22729451764143718517),
  396. BOOST_MATH_BIG_CONSTANT(T, 53, -2.8175401114513378771),
  397. };
  398. BOOST_MATH_STATIC const T Q[] = {
  399. BOOST_MATH_BIG_CONSTANT(T, 53, 1.0),
  400. BOOST_MATH_BIG_CONSTANT(T, 53, 2.79257750980575282228),
  401. BOOST_MATH_BIG_CONSTANT(T, 53, 11.0567237927800161565),
  402. BOOST_MATH_BIG_CONSTANT(T, 53, 15.930646027911794143),
  403. BOOST_MATH_BIG_CONSTANT(T, 53, 22.9367376522880577224),
  404. BOOST_MATH_BIG_CONSTANT(T, 53, 13.5064170191802889145),
  405. BOOST_MATH_BIG_CONSTANT(T, 53, 5.48409182238641741584),
  406. };
  407. // LCOV_EXCL_STOP
  408. result = Y + tools::evaluate_polynomial(P, T(1 / z)) / tools::evaluate_polynomial(Q, T(1 / z));
  409. T hi, lo;
  410. int expon;
  411. hi = floor(ldexp(frexp(z, &expon), 26));
  412. hi = ldexp(hi, expon - 26);
  413. lo = z - hi;
  414. T sq = z * z;
  415. T err_sqr = ((hi * hi - sq) + 2 * hi * lo) + lo * lo;
  416. result *= exp(-sq) * exp(-err_sqr) / z;
  417. }
  418. }
  419. else
  420. {
  421. //
  422. // Any value of z larger than 28 will underflow to zero:
  423. //
  424. result = 0;
  425. invert = !invert;
  426. }
  427. if(invert)
  428. {
  429. prefix_adder += prefix_multiplier * 1;
  430. prefix_multiplier = -prefix_multiplier;
  431. }
  432. return prefix_adder + prefix_multiplier * result;
  433. } // template <class T, class Lanczos>T erf_imp(T z, bool invert, const Lanczos& l, const std::integral_constant<int, 53>& t)
  434. template <class T, class Policy>
  435. T erf_imp(T z, bool invert, const Policy& pol, const std::integral_constant<int, 64>& t)
  436. {
  437. BOOST_MATH_STD_USING
  438. BOOST_MATH_INSTRUMENT_CODE("64-bit precision erf_imp called");
  439. if ((boost::math::isnan)(z))
  440. return policies::raise_domain_error("boost::math::erf<%1%>(%1%)", "Expected a finite argument but got %1%", z, pol);
  441. if(z < 0)
  442. {
  443. if(!invert)
  444. return -erf_imp(T(-z), invert, pol, t);
  445. else if(z < -0.5)
  446. return 2 - erf_imp(T(-z), invert, pol, t);
  447. else
  448. return 1 + erf_imp(T(-z), false, pol, t);
  449. }
  450. T result;
  451. //
  452. // Big bunch of selection statements now to pick which
  453. // implementation to use, try to put most likely options
  454. // first:
  455. //
  456. if(z < 0.5)
  457. {
  458. //
  459. // We're going to calculate erf:
  460. //
  461. if(z == 0)
  462. {
  463. result = 0;
  464. }
  465. else if(z < 1e-10)
  466. {
  467. static const T c = BOOST_MATH_BIG_CONSTANT(T, 64, 0.003379167095512573896158903121545171688); // LCOV_EXCL_LINE
  468. result = z * 1.125 + z * c;
  469. }
  470. else
  471. {
  472. // Max Error found at long double precision = 1.623299e-20
  473. // Maximum Deviation Found: 4.326e-22
  474. // Expected Error Term: -4.326e-22
  475. // Maximum Relative Change in Control Points: 1.474e-04
  476. // LCOV_EXCL_START
  477. static const T Y = 1.044948577880859375f;
  478. static const T P[] = {
  479. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0834305892146531988966),
  480. BOOST_MATH_BIG_CONSTANT(T, 64, -0.338097283075565413695),
  481. BOOST_MATH_BIG_CONSTANT(T, 64, -0.0509602734406067204596),
  482. BOOST_MATH_BIG_CONSTANT(T, 64, -0.00904906346158537794396),
  483. BOOST_MATH_BIG_CONSTANT(T, 64, -0.000489468651464798669181),
  484. BOOST_MATH_BIG_CONSTANT(T, 64, -0.200305626366151877759e-4),
  485. };
  486. static const T Q[] = {
  487. BOOST_MATH_BIG_CONSTANT(T, 64, 1.0),
  488. BOOST_MATH_BIG_CONSTANT(T, 64, 0.455817300515875172439),
  489. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0916537354356241792007),
  490. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0102722652675910031202),
  491. BOOST_MATH_BIG_CONSTANT(T, 64, 0.000650511752687851548735),
  492. BOOST_MATH_BIG_CONSTANT(T, 64, 0.189532519105655496778e-4),
  493. };
  494. // LCOV_EXCL_STOP
  495. result = z * (Y + tools::evaluate_polynomial(P, T(z * z)) / tools::evaluate_polynomial(Q, T(z * z)));
  496. }
  497. }
  498. else if(invert ? (z < 110) : (z < 6.6f))
  499. {
  500. //
  501. // We'll be calculating erfc:
  502. //
  503. invert = !invert;
  504. if(z < 1.5)
  505. {
  506. // Max Error found at long double precision = 3.239590e-20
  507. // Maximum Deviation Found: 2.241e-20
  508. // Expected Error Term: -2.241e-20
  509. // Maximum Relative Change in Control Points: 5.110e-03
  510. // LCOV_EXCL_START
  511. static const T Y = 0.405935764312744140625f;
  512. static const T P[] = {
  513. BOOST_MATH_BIG_CONSTANT(T, 64, -0.0980905922162812031672),
  514. BOOST_MATH_BIG_CONSTANT(T, 64, 0.159989089922969141329),
  515. BOOST_MATH_BIG_CONSTANT(T, 64, 0.222359821619935712378),
  516. BOOST_MATH_BIG_CONSTANT(T, 64, 0.127303921703577362312),
  517. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0384057530342762400273),
  518. BOOST_MATH_BIG_CONSTANT(T, 64, 0.00628431160851156719325),
  519. BOOST_MATH_BIG_CONSTANT(T, 64, 0.000441266654514391746428),
  520. BOOST_MATH_BIG_CONSTANT(T, 64, 0.266689068336295642561e-7),
  521. };
  522. static const T Q[] = {
  523. BOOST_MATH_BIG_CONSTANT(T, 64, 1.0),
  524. BOOST_MATH_BIG_CONSTANT(T, 64, 2.03237474985469469291),
  525. BOOST_MATH_BIG_CONSTANT(T, 64, 1.78355454954969405222),
  526. BOOST_MATH_BIG_CONSTANT(T, 64, 0.867940326293760578231),
  527. BOOST_MATH_BIG_CONSTANT(T, 64, 0.248025606990021698392),
  528. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0396649631833002269861),
  529. BOOST_MATH_BIG_CONSTANT(T, 64, 0.00279220237309449026796),
  530. };
  531. // LCOV_EXCL_STOP
  532. result = Y + tools::evaluate_polynomial(P, T(z - 0.5f)) / tools::evaluate_polynomial(Q, T(z - 0.5f));
  533. T hi, lo;
  534. int expon;
  535. hi = floor(ldexp(frexp(z, &expon), 32));
  536. hi = ldexp(hi, expon - 32);
  537. lo = z - hi;
  538. T sq = z * z;
  539. T err_sqr = ((hi * hi - sq) + 2 * hi * lo) + lo * lo;
  540. result *= exp(-sq) * exp(-err_sqr) / z;
  541. }
  542. else if(z < 2.5)
  543. {
  544. // Max Error found at long double precision = 3.686211e-21
  545. // Maximum Deviation Found: 1.495e-21
  546. // Expected Error Term: -1.494e-21
  547. // Maximum Relative Change in Control Points: 1.793e-04
  548. // LCOV_EXCL_START
  549. static const T Y = 0.50672817230224609375f;
  550. static const T P[] = {
  551. BOOST_MATH_BIG_CONSTANT(T, 64, -0.024350047620769840217),
  552. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0343522687935671451309),
  553. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0505420824305544949541),
  554. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0257479325917757388209),
  555. BOOST_MATH_BIG_CONSTANT(T, 64, 0.00669349844190354356118),
  556. BOOST_MATH_BIG_CONSTANT(T, 64, 0.00090807914416099524444),
  557. BOOST_MATH_BIG_CONSTANT(T, 64, 0.515917266698050027934e-4),
  558. };
  559. static const T Q[] = {
  560. BOOST_MATH_BIG_CONSTANT(T, 64, 1.0),
  561. BOOST_MATH_BIG_CONSTANT(T, 64, 1.71657861671930336344),
  562. BOOST_MATH_BIG_CONSTANT(T, 64, 1.26409634824280366218),
  563. BOOST_MATH_BIG_CONSTANT(T, 64, 0.512371437838969015941),
  564. BOOST_MATH_BIG_CONSTANT(T, 64, 0.120902623051120950935),
  565. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0158027197831887485261),
  566. BOOST_MATH_BIG_CONSTANT(T, 64, 0.000897871370778031611439),
  567. };
  568. // LCOV_EXCL_STOP
  569. result = Y + tools::evaluate_polynomial(P, T(z - 1.5f)) / tools::evaluate_polynomial(Q, T(z - 1.5f));
  570. T hi, lo;
  571. int expon;
  572. hi = floor(ldexp(frexp(z, &expon), 32));
  573. hi = ldexp(hi, expon - 32);
  574. lo = z - hi;
  575. T sq = z * z;
  576. T err_sqr = ((hi * hi - sq) + 2 * hi * lo) + lo * lo;
  577. result *= exp(-sq) * exp(-err_sqr) / z;
  578. }
  579. else if(z < 4.5)
  580. {
  581. // Maximum Deviation Found: 1.107e-20
  582. // Expected Error Term: -1.106e-20
  583. // Maximum Relative Change in Control Points: 1.709e-04
  584. // Max Error found at long double precision = 1.446908e-20
  585. // LCOV_EXCL_START
  586. static const T Y = 0.5405750274658203125f;
  587. static const T P[] = {
  588. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0029527671653097284033),
  589. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0141853245895495604051),
  590. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0104959584626432293901),
  591. BOOST_MATH_BIG_CONSTANT(T, 64, 0.00343963795976100077626),
  592. BOOST_MATH_BIG_CONSTANT(T, 64, 0.00059065441194877637899),
  593. BOOST_MATH_BIG_CONSTANT(T, 64, 0.523435380636174008685e-4),
  594. BOOST_MATH_BIG_CONSTANT(T, 64, 0.189896043050331257262e-5),
  595. };
  596. static const T Q[] = {
  597. BOOST_MATH_BIG_CONSTANT(T, 64, 1.0),
  598. BOOST_MATH_BIG_CONSTANT(T, 64, 1.19352160185285642574),
  599. BOOST_MATH_BIG_CONSTANT(T, 64, 0.603256964363454392857),
  600. BOOST_MATH_BIG_CONSTANT(T, 64, 0.165411142458540585835),
  601. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0259729870946203166468),
  602. BOOST_MATH_BIG_CONSTANT(T, 64, 0.00221657568292893699158),
  603. BOOST_MATH_BIG_CONSTANT(T, 64, 0.804149464190309799804e-4),
  604. };
  605. // LCOV_EXCL_STOP
  606. result = Y + tools::evaluate_polynomial(P, T(z - 3.5f)) / tools::evaluate_polynomial(Q, T(z - 3.5f));
  607. T hi, lo;
  608. int expon;
  609. hi = floor(ldexp(frexp(z, &expon), 32));
  610. hi = ldexp(hi, expon - 32);
  611. lo = z - hi;
  612. T sq = z * z;
  613. T err_sqr = ((hi * hi - sq) + 2 * hi * lo) + lo * lo;
  614. result *= exp(-sq) * exp(-err_sqr) / z;
  615. }
  616. else
  617. {
  618. // Max Error found at long double precision = 7.961166e-21
  619. // Maximum Deviation Found: 6.677e-21
  620. // Expected Error Term: 6.676e-21
  621. // Maximum Relative Change in Control Points: 2.319e-05
  622. // LCOV_EXCL_START
  623. static const T Y = 0.55825519561767578125f;
  624. static const T P[] = {
  625. BOOST_MATH_BIG_CONSTANT(T, 64, 0.00593438793008050214106),
  626. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0280666231009089713937),
  627. BOOST_MATH_BIG_CONSTANT(T, 64, -0.141597835204583050043),
  628. BOOST_MATH_BIG_CONSTANT(T, 64, -0.978088201154300548842),
  629. BOOST_MATH_BIG_CONSTANT(T, 64, -5.47351527796012049443),
  630. BOOST_MATH_BIG_CONSTANT(T, 64, -13.8677304660245326627),
  631. BOOST_MATH_BIG_CONSTANT(T, 64, -27.1274948720539821722),
  632. BOOST_MATH_BIG_CONSTANT(T, 64, -29.2545152747009461519),
  633. BOOST_MATH_BIG_CONSTANT(T, 64, -16.8865774499799676937),
  634. };
  635. static const T Q[] = {
  636. BOOST_MATH_BIG_CONSTANT(T, 64, 1.0),
  637. BOOST_MATH_BIG_CONSTANT(T, 64, 4.72948911186645394541),
  638. BOOST_MATH_BIG_CONSTANT(T, 64, 23.6750543147695749212),
  639. BOOST_MATH_BIG_CONSTANT(T, 64, 60.0021517335693186785),
  640. BOOST_MATH_BIG_CONSTANT(T, 64, 131.766251645149522868),
  641. BOOST_MATH_BIG_CONSTANT(T, 64, 178.167924971283482513),
  642. BOOST_MATH_BIG_CONSTANT(T, 64, 182.499390505915222699),
  643. BOOST_MATH_BIG_CONSTANT(T, 64, 104.365251479578577989),
  644. BOOST_MATH_BIG_CONSTANT(T, 64, 30.8365511891224291717),
  645. };
  646. // LCOV_EXCL_STOP
  647. result = Y + tools::evaluate_polynomial(P, T(1 / z)) / tools::evaluate_polynomial(Q, T(1 / z));
  648. T hi, lo;
  649. int expon;
  650. hi = floor(ldexp(frexp(z, &expon), 32));
  651. hi = ldexp(hi, expon - 32);
  652. lo = z - hi;
  653. T sq = z * z;
  654. T err_sqr = ((hi * hi - sq) + 2 * hi * lo) + lo * lo;
  655. result *= exp(-sq) * exp(-err_sqr) / z;
  656. }
  657. }
  658. else
  659. {
  660. //
  661. // Any value of z larger than 110 will underflow to zero:
  662. //
  663. result = 0;
  664. invert = !invert;
  665. }
  666. if(invert)
  667. {
  668. result = 1 - result;
  669. }
  670. return result;
  671. } // template <class T, class Lanczos>T erf_imp(T z, bool invert, const Lanczos& l, const std::integral_constant<int, 64>& t)
  672. // LCOV_EXCL_START multiprecision case only, excluded from coverage analysis
  673. template <class T, class Policy>
  674. T erf_imp(T z, bool invert, const Policy& pol, const std::integral_constant<int, 113>& t)
  675. {
  676. BOOST_MATH_STD_USING
  677. BOOST_MATH_INSTRUMENT_CODE("113-bit precision erf_imp called");
  678. if ((boost::math::isnan)(z))
  679. return policies::raise_domain_error("boost::math::erf<%1%>(%1%)", "Expected a finite argument but got %1%", z, pol);
  680. if(z < 0)
  681. {
  682. if (!invert)
  683. return -erf_imp(T(-z), invert, pol, t);
  684. else if(z < -0.5)
  685. return 2 - erf_imp(T(-z), invert, pol, t);
  686. else
  687. return 1 + erf_imp(T(-z), false, pol, t);
  688. }
  689. T result;
  690. //
  691. // Big bunch of selection statements now to pick which
  692. // implementation to use, try to put most likely options
  693. // first:
  694. //
  695. if(z < 0.5)
  696. {
  697. //
  698. // We're going to calculate erf:
  699. //
  700. if(z == 0)
  701. {
  702. result = 0;
  703. }
  704. else if(z < 1e-20)
  705. {
  706. static const T c = BOOST_MATH_BIG_CONSTANT(T, 113, 0.003379167095512573896158903121545171688);
  707. result = z * 1.125 + z * c;
  708. }
  709. else
  710. {
  711. // Max Error found at long double precision = 2.342380e-35
  712. // Maximum Deviation Found: 6.124e-36
  713. // Expected Error Term: -6.124e-36
  714. // Maximum Relative Change in Control Points: 3.492e-10
  715. static const T Y = 1.0841522216796875f;
  716. static const T P[] = {
  717. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0442269454158250738961589031215451778),
  718. BOOST_MATH_BIG_CONSTANT(T, 113, -0.35549265736002144875335323556961233),
  719. BOOST_MATH_BIG_CONSTANT(T, 113, -0.0582179564566667896225454670863270393),
  720. BOOST_MATH_BIG_CONSTANT(T, 113, -0.0112694696904802304229950538453123925),
  721. BOOST_MATH_BIG_CONSTANT(T, 113, -0.000805730648981801146251825329609079099),
  722. BOOST_MATH_BIG_CONSTANT(T, 113, -0.566304966591936566229702842075966273e-4),
  723. BOOST_MATH_BIG_CONSTANT(T, 113, -0.169655010425186987820201021510002265e-5),
  724. BOOST_MATH_BIG_CONSTANT(T, 113, -0.344448249920445916714548295433198544e-7),
  725. };
  726. static const T Q[] = {
  727. BOOST_MATH_BIG_CONSTANT(T, 113, 1.0),
  728. BOOST_MATH_BIG_CONSTANT(T, 113, 0.466542092785657604666906909196052522),
  729. BOOST_MATH_BIG_CONSTANT(T, 113, 0.100005087012526447295176964142107611),
  730. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0128341535890117646540050072234142603),
  731. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00107150448466867929159660677016658186),
  732. BOOST_MATH_BIG_CONSTANT(T, 113, 0.586168368028999183607733369248338474e-4),
  733. BOOST_MATH_BIG_CONSTANT(T, 113, 0.196230608502104324965623171516808796e-5),
  734. BOOST_MATH_BIG_CONSTANT(T, 113, 0.313388521582925207734229967907890146e-7),
  735. };
  736. result = z * (Y + tools::evaluate_polynomial(P, T(z * z)) / tools::evaluate_polynomial(Q, T(z * z)));
  737. }
  738. }
  739. else if(invert ? (z < 110) : (z < 8.65f))
  740. {
  741. //
  742. // We'll be calculating erfc:
  743. //
  744. invert = !invert;
  745. if(z < 1)
  746. {
  747. // Max Error found at long double precision = 3.246278e-35
  748. // Maximum Deviation Found: 1.388e-35
  749. // Expected Error Term: 1.387e-35
  750. // Maximum Relative Change in Control Points: 6.127e-05
  751. static const T Y = 0.371877193450927734375f;
  752. static const T P[] = {
  753. BOOST_MATH_BIG_CONSTANT(T, 113, -0.0640320213544647969396032886581290455),
  754. BOOST_MATH_BIG_CONSTANT(T, 113, 0.200769874440155895637857443946706731),
  755. BOOST_MATH_BIG_CONSTANT(T, 113, 0.378447199873537170666487408805779826),
  756. BOOST_MATH_BIG_CONSTANT(T, 113, 0.30521399466465939450398642044975127),
  757. BOOST_MATH_BIG_CONSTANT(T, 113, 0.146890026406815277906781824723458196),
  758. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0464837937749539978247589252732769567),
  759. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00987895759019540115099100165904822903),
  760. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00137507575429025512038051025154301132),
  761. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0001144764551085935580772512359680516),
  762. BOOST_MATH_BIG_CONSTANT(T, 113, 0.436544865032836914773944382339900079e-5),
  763. };
  764. static const T Q[] = {
  765. BOOST_MATH_BIG_CONSTANT(T, 113, 1.0),
  766. BOOST_MATH_BIG_CONSTANT(T, 113, 2.47651182872457465043733800302427977),
  767. BOOST_MATH_BIG_CONSTANT(T, 113, 2.78706486002517996428836400245547955),
  768. BOOST_MATH_BIG_CONSTANT(T, 113, 1.87295924621659627926365005293130693),
  769. BOOST_MATH_BIG_CONSTANT(T, 113, 0.829375825174365625428280908787261065),
  770. BOOST_MATH_BIG_CONSTANT(T, 113, 0.251334771307848291593780143950311514),
  771. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0522110268876176186719436765734722473),
  772. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00718332151250963182233267040106902368),
  773. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000595279058621482041084986219276392459),
  774. BOOST_MATH_BIG_CONSTANT(T, 113, 0.226988669466501655990637599399326874e-4),
  775. BOOST_MATH_BIG_CONSTANT(T, 113, 0.270666232259029102353426738909226413e-10),
  776. };
  777. result = Y + tools::evaluate_polynomial(P, T(z - 0.5f)) / tools::evaluate_polynomial(Q, T(z - 0.5f));
  778. T hi, lo;
  779. int expon;
  780. hi = floor(ldexp(frexp(z, &expon), 56));
  781. hi = ldexp(hi, expon - 56);
  782. lo = z - hi;
  783. T sq = z * z;
  784. T err_sqr = ((hi * hi - sq) + 2 * hi * lo) + lo * lo;
  785. result *= exp(-sq) * exp(-err_sqr) / z;
  786. }
  787. else if(z < 1.5)
  788. {
  789. // Max Error found at long double precision = 2.215785e-35
  790. // Maximum Deviation Found: 1.539e-35
  791. // Expected Error Term: 1.538e-35
  792. // Maximum Relative Change in Control Points: 6.104e-05
  793. static const T Y = 0.45658016204833984375f;
  794. static const T P[] = {
  795. BOOST_MATH_BIG_CONSTANT(T, 113, -0.0289965858925328393392496555094848345),
  796. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0868181194868601184627743162571779226),
  797. BOOST_MATH_BIG_CONSTANT(T, 113, 0.169373435121178901746317404936356745),
  798. BOOST_MATH_BIG_CONSTANT(T, 113, 0.13350446515949251201104889028133486),
  799. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0617447837290183627136837688446313313),
  800. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0185618495228251406703152962489700468),
  801. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00371949406491883508764162050169531013),
  802. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000485121708792921297742105775823900772),
  803. BOOST_MATH_BIG_CONSTANT(T, 113, 0.376494706741453489892108068231400061e-4),
  804. BOOST_MATH_BIG_CONSTANT(T, 113, 0.133166058052466262415271732172490045e-5),
  805. };
  806. static const T Q[] = {
  807. BOOST_MATH_BIG_CONSTANT(T, 113, 1.0),
  808. BOOST_MATH_BIG_CONSTANT(T, 113, 2.32970330146503867261275580968135126),
  809. BOOST_MATH_BIG_CONSTANT(T, 113, 2.46325715420422771961250513514928746),
  810. BOOST_MATH_BIG_CONSTANT(T, 113, 1.55307882560757679068505047390857842),
  811. BOOST_MATH_BIG_CONSTANT(T, 113, 0.644274289865972449441174485441409076),
  812. BOOST_MATH_BIG_CONSTANT(T, 113, 0.182609091063258208068606847453955649),
  813. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0354171651271241474946129665801606795),
  814. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00454060370165285246451879969534083997),
  815. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000349871943711566546821198612518656486),
  816. BOOST_MATH_BIG_CONSTANT(T, 113, 0.123749319840299552925421880481085392e-4),
  817. };
  818. result = Y + tools::evaluate_polynomial(P, T(z - 1.0f)) / tools::evaluate_polynomial(Q, T(z - 1.0f));
  819. T hi, lo;
  820. int expon;
  821. hi = floor(ldexp(frexp(z, &expon), 56));
  822. hi = ldexp(hi, expon - 56);
  823. lo = z - hi;
  824. T sq = z * z;
  825. T err_sqr = ((hi * hi - sq) + 2 * hi * lo) + lo * lo;
  826. result *= exp(-sq) * exp(-err_sqr) / z;
  827. }
  828. else if(z < 2.25)
  829. {
  830. // Maximum Deviation Found: 1.418e-35
  831. // Expected Error Term: 1.418e-35
  832. // Maximum Relative Change in Control Points: 1.316e-04
  833. // Max Error found at long double precision = 1.998462e-35
  834. static const T Y = 0.50250148773193359375f;
  835. static const T P[] = {
  836. BOOST_MATH_BIG_CONSTANT(T, 113, -0.0201233630504573402185161184151016606),
  837. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0331864357574860196516686996302305002),
  838. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0716562720864787193337475444413405461),
  839. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0545835322082103985114927569724880658),
  840. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0236692635189696678976549720784989593),
  841. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00656970902163248872837262539337601845),
  842. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00120282643299089441390490459256235021),
  843. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000142123229065182650020762792081622986),
  844. BOOST_MATH_BIG_CONSTANT(T, 113, 0.991531438367015135346716277792989347e-5),
  845. BOOST_MATH_BIG_CONSTANT(T, 113, 0.312857043762117596999398067153076051e-6),
  846. };
  847. static const T Q[] = {
  848. BOOST_MATH_BIG_CONSTANT(T, 113, 1.0),
  849. BOOST_MATH_BIG_CONSTANT(T, 113, 2.13506082409097783827103424943508554),
  850. BOOST_MATH_BIG_CONSTANT(T, 113, 2.06399257267556230937723190496806215),
  851. BOOST_MATH_BIG_CONSTANT(T, 113, 1.18678481279932541314830499880691109),
  852. BOOST_MATH_BIG_CONSTANT(T, 113, 0.447733186643051752513538142316799562),
  853. BOOST_MATH_BIG_CONSTANT(T, 113, 0.11505680005657879437196953047542148),
  854. BOOST_MATH_BIG_CONSTANT(T, 113, 0.020163993632192726170219663831914034),
  855. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00232708971840141388847728782209730585),
  856. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000160733201627963528519726484608224112),
  857. BOOST_MATH_BIG_CONSTANT(T, 113, 0.507158721790721802724402992033269266e-5),
  858. BOOST_MATH_BIG_CONSTANT(T, 113, 0.18647774409821470950544212696270639e-12),
  859. };
  860. result = Y + tools::evaluate_polynomial(P, T(z - 1.5f)) / tools::evaluate_polynomial(Q, T(z - 1.5f));
  861. T hi, lo;
  862. int expon;
  863. hi = floor(ldexp(frexp(z, &expon), 56));
  864. hi = ldexp(hi, expon - 56);
  865. lo = z - hi;
  866. T sq = z * z;
  867. T err_sqr = ((hi * hi - sq) + 2 * hi * lo) + lo * lo;
  868. result *= exp(-sq) * exp(-err_sqr) / z;
  869. }
  870. else if (z < 3)
  871. {
  872. // Maximum Deviation Found: 3.575e-36
  873. // Expected Error Term: 3.575e-36
  874. // Maximum Relative Change in Control Points: 7.103e-05
  875. // Max Error found at long double precision = 5.794737e-36
  876. static const T Y = 0.52896785736083984375f;
  877. static const T P[] = {
  878. BOOST_MATH_BIG_CONSTANT(T, 113, -0.00902152521745813634562524098263360074),
  879. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0145207142776691539346923710537580927),
  880. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0301681239582193983824211995978678571),
  881. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0215548540823305814379020678660434461),
  882. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00864683476267958365678294164340749949),
  883. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00219693096885585491739823283511049902),
  884. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000364961639163319762492184502159894371),
  885. BOOST_MATH_BIG_CONSTANT(T, 113, 0.388174251026723752769264051548703059e-4),
  886. BOOST_MATH_BIG_CONSTANT(T, 113, 0.241918026931789436000532513553594321e-5),
  887. BOOST_MATH_BIG_CONSTANT(T, 113, 0.676586625472423508158937481943649258e-7),
  888. };
  889. static const T Q[] = {
  890. BOOST_MATH_BIG_CONSTANT(T, 113, 1.0),
  891. BOOST_MATH_BIG_CONSTANT(T, 113, 1.93669171363907292305550231764920001),
  892. BOOST_MATH_BIG_CONSTANT(T, 113, 1.69468476144051356810672506101377494),
  893. BOOST_MATH_BIG_CONSTANT(T, 113, 0.880023580986436640372794392579985511),
  894. BOOST_MATH_BIG_CONSTANT(T, 113, 0.299099106711315090710836273697708402),
  895. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0690593962363545715997445583603382337),
  896. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0108427016361318921960863149875360222),
  897. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00111747247208044534520499324234317695),
  898. BOOST_MATH_BIG_CONSTANT(T, 113, 0.686843205749767250666787987163701209e-4),
  899. BOOST_MATH_BIG_CONSTANT(T, 113, 0.192093541425429248675532015101904262e-5),
  900. };
  901. result = Y + tools::evaluate_polynomial(P, T(z - 2.25f)) / tools::evaluate_polynomial(Q, T(z - 2.25f));
  902. T hi, lo;
  903. int expon;
  904. hi = floor(ldexp(frexp(z, &expon), 56));
  905. hi = ldexp(hi, expon - 56);
  906. lo = z - hi;
  907. T sq = z * z;
  908. T err_sqr = ((hi * hi - sq) + 2 * hi * lo) + lo * lo;
  909. result *= exp(-sq) * exp(-err_sqr) / z;
  910. }
  911. else if(z < 3.5)
  912. {
  913. // Maximum Deviation Found: 8.126e-37
  914. // Expected Error Term: -8.126e-37
  915. // Maximum Relative Change in Control Points: 1.363e-04
  916. // Max Error found at long double precision = 1.747062e-36
  917. static const T Y = 0.54037380218505859375f;
  918. static const T P[] = {
  919. BOOST_MATH_BIG_CONSTANT(T, 113, -0.0033703486408887424921155540591370375),
  920. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0104948043110005245215286678898115811),
  921. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0148530118504000311502310457390417795),
  922. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00816693029245443090102738825536188916),
  923. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00249716579989140882491939681805594585),
  924. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0004655591010047353023978045800916647),
  925. BOOST_MATH_BIG_CONSTANT(T, 113, 0.531129557920045295895085236636025323e-4),
  926. BOOST_MATH_BIG_CONSTANT(T, 113, 0.343526765122727069515775194111741049e-5),
  927. BOOST_MATH_BIG_CONSTANT(T, 113, 0.971120407556888763695313774578711839e-7),
  928. };
  929. static const T Q[] = {
  930. BOOST_MATH_BIG_CONSTANT(T, 113, 1.0),
  931. BOOST_MATH_BIG_CONSTANT(T, 113, 1.59911256167540354915906501335919317),
  932. BOOST_MATH_BIG_CONSTANT(T, 113, 1.136006830764025173864831382946934),
  933. BOOST_MATH_BIG_CONSTANT(T, 113, 0.468565867990030871678574840738423023),
  934. BOOST_MATH_BIG_CONSTANT(T, 113, 0.122821824954470343413956476900662236),
  935. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0209670914950115943338996513330141633),
  936. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00227845718243186165620199012883547257),
  937. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000144243326443913171313947613547085553),
  938. BOOST_MATH_BIG_CONSTANT(T, 113, 0.407763415954267700941230249989140046e-5),
  939. };
  940. result = Y + tools::evaluate_polynomial(P, T(z - 3.0f)) / tools::evaluate_polynomial(Q, T(z - 3.0f));
  941. T hi, lo;
  942. int expon;
  943. hi = floor(ldexp(frexp(z, &expon), 56));
  944. hi = ldexp(hi, expon - 56);
  945. lo = z - hi;
  946. T sq = z * z;
  947. T err_sqr = ((hi * hi - sq) + 2 * hi * lo) + lo * lo;
  948. result *= exp(-sq) * exp(-err_sqr) / z;
  949. }
  950. else if(z < 5.5)
  951. {
  952. // Maximum Deviation Found: 5.804e-36
  953. // Expected Error Term: -5.803e-36
  954. // Maximum Relative Change in Control Points: 2.475e-05
  955. // Max Error found at long double precision = 1.349545e-35
  956. static const T Y = 0.55000019073486328125f;
  957. static const T P[] = {
  958. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00118142849742309772151454518093813615),
  959. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0072201822885703318172366893469382745),
  960. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0078782276276860110721875733778481505),
  961. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00418229166204362376187593976656261146),
  962. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00134198400587769200074194304298642705),
  963. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000283210387078004063264777611497435572),
  964. BOOST_MATH_BIG_CONSTANT(T, 113, 0.405687064094911866569295610914844928e-4),
  965. BOOST_MATH_BIG_CONSTANT(T, 113, 0.39348283801568113807887364414008292e-5),
  966. BOOST_MATH_BIG_CONSTANT(T, 113, 0.248798540917787001526976889284624449e-6),
  967. BOOST_MATH_BIG_CONSTANT(T, 113, 0.929502490223452372919607105387474751e-8),
  968. BOOST_MATH_BIG_CONSTANT(T, 113, 0.156161469668275442569286723236274457e-9),
  969. };
  970. static const T Q[] = {
  971. BOOST_MATH_BIG_CONSTANT(T, 113, 1.0),
  972. BOOST_MATH_BIG_CONSTANT(T, 113, 1.52955245103668419479878456656709381),
  973. BOOST_MATH_BIG_CONSTANT(T, 113, 1.06263944820093830054635017117417064),
  974. BOOST_MATH_BIG_CONSTANT(T, 113, 0.441684612681607364321013134378316463),
  975. BOOST_MATH_BIG_CONSTANT(T, 113, 0.121665258426166960049773715928906382),
  976. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0232134512374747691424978642874321434),
  977. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00310778180686296328582860464875562636),
  978. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000288361770756174705123674838640161693),
  979. BOOST_MATH_BIG_CONSTANT(T, 113, 0.177529187194133944622193191942300132e-4),
  980. BOOST_MATH_BIG_CONSTANT(T, 113, 0.655068544833064069223029299070876623e-6),
  981. BOOST_MATH_BIG_CONSTANT(T, 113, 0.11005507545746069573608988651927452e-7),
  982. };
  983. result = Y + tools::evaluate_polynomial(P, T(z - 4.5f)) / tools::evaluate_polynomial(Q, T(z - 4.5f));
  984. T hi, lo;
  985. int expon;
  986. hi = floor(ldexp(frexp(z, &expon), 56));
  987. hi = ldexp(hi, expon - 56);
  988. lo = z - hi;
  989. T sq = z * z;
  990. T err_sqr = ((hi * hi - sq) + 2 * hi * lo) + lo * lo;
  991. result *= exp(-sq) * exp(-err_sqr) / z;
  992. }
  993. else if(z < 7.5)
  994. {
  995. // Maximum Deviation Found: 1.007e-36
  996. // Expected Error Term: 1.007e-36
  997. // Maximum Relative Change in Control Points: 1.027e-03
  998. // Max Error found at long double precision = 2.646420e-36
  999. static const T Y = 0.5574436187744140625f;
  1000. static const T P[] = {
  1001. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000293236907400849056269309713064107674),
  1002. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00225110719535060642692275221961480162),
  1003. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00190984458121502831421717207849429799),
  1004. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000747757733460111743833929141001680706),
  1005. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000170663175280949889583158597373928096),
  1006. BOOST_MATH_BIG_CONSTANT(T, 113, 0.246441188958013822253071608197514058e-4),
  1007. BOOST_MATH_BIG_CONSTANT(T, 113, 0.229818000860544644974205957895688106e-5),
  1008. BOOST_MATH_BIG_CONSTANT(T, 113, 0.134886977703388748488480980637704864e-6),
  1009. BOOST_MATH_BIG_CONSTANT(T, 113, 0.454764611880548962757125070106650958e-8),
  1010. BOOST_MATH_BIG_CONSTANT(T, 113, 0.673002744115866600294723141176820155e-10),
  1011. };
  1012. static const T Q[] = {
  1013. BOOST_MATH_BIG_CONSTANT(T, 113, 1.0),
  1014. BOOST_MATH_BIG_CONSTANT(T, 113, 1.12843690320861239631195353379313367),
  1015. BOOST_MATH_BIG_CONSTANT(T, 113, 0.569900657061622955362493442186537259),
  1016. BOOST_MATH_BIG_CONSTANT(T, 113, 0.169094404206844928112348730277514273),
  1017. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0324887449084220415058158657252147063),
  1018. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00419252877436825753042680842608219552),
  1019. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00036344133176118603523976748563178578),
  1020. BOOST_MATH_BIG_CONSTANT(T, 113, 0.204123895931375107397698245752850347e-4),
  1021. BOOST_MATH_BIG_CONSTANT(T, 113, 0.674128352521481412232785122943508729e-6),
  1022. BOOST_MATH_BIG_CONSTANT(T, 113, 0.997637501418963696542159244436245077e-8),
  1023. };
  1024. result = Y + tools::evaluate_polynomial(P, T(z - 6.5f)) / tools::evaluate_polynomial(Q, T(z - 6.5f));
  1025. T hi, lo;
  1026. int expon;
  1027. hi = floor(ldexp(frexp(z, &expon), 56));
  1028. hi = ldexp(hi, expon - 56);
  1029. lo = z - hi;
  1030. T sq = z * z;
  1031. T err_sqr = ((hi * hi - sq) + 2 * hi * lo) + lo * lo;
  1032. result *= exp(-sq) * exp(-err_sqr) / z;
  1033. }
  1034. else if(z < 11.5)
  1035. {
  1036. // Maximum Deviation Found: 8.380e-36
  1037. // Expected Error Term: 8.380e-36
  1038. // Maximum Relative Change in Control Points: 2.632e-06
  1039. // Max Error found at long double precision = 9.849522e-36
  1040. static const T Y = 0.56083202362060546875f;
  1041. static const T P[] = {
  1042. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000282420728751494363613829834891390121),
  1043. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00175387065018002823433704079355125161),
  1044. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0021344978564889819420775336322920375),
  1045. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00124151356560137532655039683963075661),
  1046. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000423600733566948018555157026862139644),
  1047. BOOST_MATH_BIG_CONSTANT(T, 113, 0.914030340865175237133613697319509698e-4),
  1048. BOOST_MATH_BIG_CONSTANT(T, 113, 0.126999927156823363353809747017945494e-4),
  1049. BOOST_MATH_BIG_CONSTANT(T, 113, 0.110610959842869849776179749369376402e-5),
  1050. BOOST_MATH_BIG_CONSTANT(T, 113, 0.55075079477173482096725348704634529e-7),
  1051. BOOST_MATH_BIG_CONSTANT(T, 113, 0.119735694018906705225870691331543806e-8),
  1052. };
  1053. static const T Q[] = {
  1054. BOOST_MATH_BIG_CONSTANT(T, 113, 1.0),
  1055. BOOST_MATH_BIG_CONSTANT(T, 113, 1.69889613396167354566098060039549882),
  1056. BOOST_MATH_BIG_CONSTANT(T, 113, 1.28824647372749624464956031163282674),
  1057. BOOST_MATH_BIG_CONSTANT(T, 113, 0.572297795434934493541628008224078717),
  1058. BOOST_MATH_BIG_CONSTANT(T, 113, 0.164157697425571712377043857240773164),
  1059. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0315311145224594430281219516531649562),
  1060. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00405588922155632380812945849777127458),
  1061. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000336929033691445666232029762868642417),
  1062. BOOST_MATH_BIG_CONSTANT(T, 113, 0.164033049810404773469413526427932109e-4),
  1063. BOOST_MATH_BIG_CONSTANT(T, 113, 0.356615210500531410114914617294694857e-6),
  1064. };
  1065. result = Y + tools::evaluate_polynomial(P, T(z / 2 - 4.75f)) / tools::evaluate_polynomial(Q, T(z / 2 - 4.75f));
  1066. T hi, lo;
  1067. int expon;
  1068. hi = floor(ldexp(frexp(z, &expon), 56));
  1069. hi = ldexp(hi, expon - 56);
  1070. lo = z - hi;
  1071. T sq = z * z;
  1072. T err_sqr = ((hi * hi - sq) + 2 * hi * lo) + lo * lo;
  1073. result *= exp(-sq) * exp(-err_sqr) / z;
  1074. }
  1075. else
  1076. {
  1077. // Maximum Deviation Found: 1.132e-35
  1078. // Expected Error Term: -1.132e-35
  1079. // Maximum Relative Change in Control Points: 4.674e-04
  1080. // Max Error found at long double precision = 1.162590e-35
  1081. static const T Y = 0.5632686614990234375f;
  1082. static const T P[] = {
  1083. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000920922048732849448079451574171836943),
  1084. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00321439044532288750501700028748922439),
  1085. BOOST_MATH_BIG_CONSTANT(T, 113, -0.250455263029390118657884864261823431),
  1086. BOOST_MATH_BIG_CONSTANT(T, 113, -0.906807635364090342031792404764598142),
  1087. BOOST_MATH_BIG_CONSTANT(T, 113, -8.92233572835991735876688745989985565),
  1088. BOOST_MATH_BIG_CONSTANT(T, 113, -21.7797433494422564811782116907878495),
  1089. BOOST_MATH_BIG_CONSTANT(T, 113, -91.1451915251976354349734589601171659),
  1090. BOOST_MATH_BIG_CONSTANT(T, 113, -144.1279109655993927069052125017673),
  1091. BOOST_MATH_BIG_CONSTANT(T, 113, -313.845076581796338665519022313775589),
  1092. BOOST_MATH_BIG_CONSTANT(T, 113, -273.11378811923343424081101235736475),
  1093. BOOST_MATH_BIG_CONSTANT(T, 113, -271.651566205951067025696102600443452),
  1094. BOOST_MATH_BIG_CONSTANT(T, 113, -60.0530577077238079968843307523245547),
  1095. };
  1096. static const T Q[] = {
  1097. BOOST_MATH_BIG_CONSTANT(T, 113, 1.0),
  1098. BOOST_MATH_BIG_CONSTANT(T, 113, 3.49040448075464744191022350947892036),
  1099. BOOST_MATH_BIG_CONSTANT(T, 113, 34.3563592467165971295915749548313227),
  1100. BOOST_MATH_BIG_CONSTANT(T, 113, 84.4993232033879023178285731843850461),
  1101. BOOST_MATH_BIG_CONSTANT(T, 113, 376.005865281206894120659401340373818),
  1102. BOOST_MATH_BIG_CONSTANT(T, 113, 629.95369438888946233003926191755125),
  1103. BOOST_MATH_BIG_CONSTANT(T, 113, 1568.35771983533158591604513304269098),
  1104. BOOST_MATH_BIG_CONSTANT(T, 113, 1646.02452040831961063640827116581021),
  1105. BOOST_MATH_BIG_CONSTANT(T, 113, 2299.96860633240298708910425594484895),
  1106. BOOST_MATH_BIG_CONSTANT(T, 113, 1222.73204392037452750381340219906374),
  1107. BOOST_MATH_BIG_CONSTANT(T, 113, 799.359797306084372350264298361110448),
  1108. BOOST_MATH_BIG_CONSTANT(T, 113, 72.7415265778588087243442792401576737),
  1109. };
  1110. result = Y + tools::evaluate_polynomial(P, T(1 / z)) / tools::evaluate_polynomial(Q, T(1 / z));
  1111. T hi, lo;
  1112. int expon;
  1113. hi = floor(ldexp(frexp(z, &expon), 56));
  1114. hi = ldexp(hi, expon - 56);
  1115. lo = z - hi;
  1116. T sq = z * z;
  1117. T err_sqr = ((hi * hi - sq) + 2 * hi * lo) + lo * lo;
  1118. result *= exp(-sq) * exp(-err_sqr) / z;
  1119. }
  1120. }
  1121. else
  1122. {
  1123. //
  1124. // Any value of z larger than 110 will underflow to zero:
  1125. //
  1126. result = 0;
  1127. invert = !invert;
  1128. }
  1129. if(invert)
  1130. {
  1131. result = 1 - result;
  1132. }
  1133. return result;
  1134. } // template <class T, class Lanczos>T erf_imp(T z, bool invert, const Lanczos& l, const std::integral_constant<int, 113>& t)
  1135. // LCOV_EXCL_STOP
  1136. } // namespace detail
  1137. template <class T, class Policy>
  1138. BOOST_MATH_GPU_ENABLED inline typename tools::promote_args<T>::type erf(T z, const Policy& /* pol */)
  1139. {
  1140. typedef typename tools::promote_args<T>::type result_type;
  1141. typedef typename policies::evaluation<result_type, Policy>::type value_type;
  1142. typedef typename policies::precision<result_type, Policy>::type precision_type;
  1143. typedef typename policies::normalise<
  1144. Policy,
  1145. policies::promote_float<false>,
  1146. policies::promote_double<false>,
  1147. policies::discrete_quantile<>,
  1148. policies::assert_undefined<> >::type forwarding_policy;
  1149. BOOST_MATH_INSTRUMENT_CODE("result_type = " << typeid(result_type).name());
  1150. BOOST_MATH_INSTRUMENT_CODE("value_type = " << typeid(value_type).name());
  1151. BOOST_MATH_INSTRUMENT_CODE("precision_type = " << typeid(precision_type).name());
  1152. typedef std::integral_constant<int,
  1153. precision_type::value <= 0 ? 0 :
  1154. precision_type::value <= 53 ? 53 :
  1155. precision_type::value <= 64 ? 64 :
  1156. precision_type::value <= 113 ? 113 : 0
  1157. > tag_type;
  1158. BOOST_MATH_INSTRUMENT_CODE("tag_type = " << typeid(tag_type).name());
  1159. return policies::checked_narrowing_cast<result_type, forwarding_policy>(detail::erf_imp(
  1160. static_cast<value_type>(z),
  1161. false,
  1162. forwarding_policy(),
  1163. tag_type()), "boost::math::erf<%1%>(%1%, %1%)");
  1164. }
  1165. template <class T, class Policy>
  1166. BOOST_MATH_GPU_ENABLED inline typename tools::promote_args<T>::type erfc(T z, const Policy& /* pol */)
  1167. {
  1168. typedef typename tools::promote_args<T>::type result_type;
  1169. typedef typename policies::evaluation<result_type, Policy>::type value_type;
  1170. typedef typename policies::precision<result_type, Policy>::type precision_type;
  1171. typedef typename policies::normalise<
  1172. Policy,
  1173. policies::promote_float<false>,
  1174. policies::promote_double<false>,
  1175. policies::discrete_quantile<>,
  1176. policies::assert_undefined<> >::type forwarding_policy;
  1177. BOOST_MATH_INSTRUMENT_CODE("result_type = " << typeid(result_type).name());
  1178. BOOST_MATH_INSTRUMENT_CODE("value_type = " << typeid(value_type).name());
  1179. BOOST_MATH_INSTRUMENT_CODE("precision_type = " << typeid(precision_type).name());
  1180. typedef std::integral_constant<int,
  1181. precision_type::value <= 0 ? 0 :
  1182. precision_type::value <= 53 ? 53 :
  1183. precision_type::value <= 64 ? 64 :
  1184. precision_type::value <= 113 ? 113 : 0
  1185. > tag_type;
  1186. BOOST_MATH_INSTRUMENT_CODE("tag_type = " << typeid(tag_type).name());
  1187. return policies::checked_narrowing_cast<result_type, forwarding_policy>(detail::erf_imp(
  1188. static_cast<value_type>(z),
  1189. true,
  1190. forwarding_policy(),
  1191. tag_type()), "boost::math::erfc<%1%>(%1%, %1%)");
  1192. }
  1193. template <class T>
  1194. BOOST_MATH_GPU_ENABLED inline typename tools::promote_args<T>::type erf(T z)
  1195. {
  1196. return boost::math::erf(z, policies::policy<>());
  1197. }
  1198. template <class T>
  1199. BOOST_MATH_GPU_ENABLED inline typename tools::promote_args<T>::type erfc(T z)
  1200. {
  1201. return boost::math::erfc(z, policies::policy<>());
  1202. }
  1203. } // namespace math
  1204. } // namespace boost
  1205. #else // Special handling for NVRTC platform
  1206. namespace boost {
  1207. namespace math {
  1208. template <typename T>
  1209. BOOST_MATH_GPU_ENABLED auto erf(T x)
  1210. {
  1211. return ::erf(x);
  1212. }
  1213. template <>
  1214. BOOST_MATH_GPU_ENABLED auto erf(float x)
  1215. {
  1216. return ::erff(x);
  1217. }
  1218. template <typename T, typename Policy>
  1219. BOOST_MATH_GPU_ENABLED auto erf(T x, const Policy&)
  1220. {
  1221. return ::erf(x);
  1222. }
  1223. template <typename Policy>
  1224. BOOST_MATH_GPU_ENABLED auto erf(float x, const Policy&)
  1225. {
  1226. return ::erff(x);
  1227. }
  1228. template <typename T>
  1229. BOOST_MATH_GPU_ENABLED auto erfc(T x)
  1230. {
  1231. return ::erfc(x);
  1232. }
  1233. template <>
  1234. BOOST_MATH_GPU_ENABLED auto erfc(float x)
  1235. {
  1236. return ::erfcf(x);
  1237. }
  1238. template <typename T, typename Policy>
  1239. BOOST_MATH_GPU_ENABLED auto erfc(T x, const Policy&)
  1240. {
  1241. return ::erfc(x);
  1242. }
  1243. template <typename Policy>
  1244. BOOST_MATH_GPU_ENABLED auto erfc(float x, const Policy&)
  1245. {
  1246. return ::erfcf(x);
  1247. }
  1248. } // namespace math
  1249. } // namespace boost
  1250. #endif // BOOST_MATH_HAS_NVRTC
  1251. #include <boost/math/special_functions/detail/erf_inv.hpp>
  1252. #endif // BOOST_MATH_SPECIAL_ERF_HPP