zeta.hpp 53 KB

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  1. // Copyright John Maddock 2007, 2014.
  2. // Use, modification and distribution are subject to the
  3. // Boost Software License, Version 1.0. (See accompanying file
  4. // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
  5. #ifndef BOOST_MATH_ZETA_HPP
  6. #define BOOST_MATH_ZETA_HPP
  7. #ifdef _MSC_VER
  8. #pragma once
  9. #endif
  10. #include <boost/math/special_functions/math_fwd.hpp>
  11. #include <boost/math/tools/precision.hpp>
  12. #include <boost/math/tools/series.hpp>
  13. #include <boost/math/tools/big_constant.hpp>
  14. #include <boost/math/policies/error_handling.hpp>
  15. #include <boost/math/special_functions/gamma.hpp>
  16. #include <boost/math/special_functions/factorials.hpp>
  17. #include <boost/math/special_functions/sin_pi.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{ namespace detail{
  28. #if 0
  29. //
  30. // This code is commented out because we have a better more rapidly converging series
  31. // now. Retained for future reference and in case the new code causes any issues down the line....
  32. //
  33. template <class T, class Policy>
  34. struct zeta_series_cache_size
  35. {
  36. //
  37. // Work how large to make our cache size when evaluating the series
  38. // evaluation: normally this is just large enough for the series
  39. // to have converged, but for arbitrary precision types we need a
  40. // really large cache to achieve reasonable precision in a reasonable
  41. // time. This is important when constructing rational approximations
  42. // to zeta for example.
  43. //
  44. typedef typename boost::math::policies::precision<T,Policy>::type precision_type;
  45. typedef typename mpl::if_<
  46. mpl::less_equal<precision_type, std::integral_constant<int, 0> >,
  47. std::integral_constant<int, 5000>,
  48. typename mpl::if_<
  49. mpl::less_equal<precision_type, std::integral_constant<int, 64> >,
  50. std::integral_constant<int, 70>,
  51. typename mpl::if_<
  52. mpl::less_equal<precision_type, std::integral_constant<int, 113> >,
  53. std::integral_constant<int, 100>,
  54. std::integral_constant<int, 5000>
  55. >::type
  56. >::type
  57. >::type type;
  58. };
  59. template <class T, class Policy>
  60. T zeta_series_imp(T s, T sc, const Policy&)
  61. {
  62. //
  63. // Series evaluation from:
  64. // Havil, J. Gamma: Exploring Euler's Constant.
  65. // Princeton, NJ: Princeton University Press, 2003.
  66. //
  67. // See also http://mathworld.wolfram.com/RiemannZetaFunction.html
  68. //
  69. BOOST_MATH_STD_USING
  70. T sum = 0;
  71. T mult = 0.5;
  72. T change;
  73. typedef typename zeta_series_cache_size<T,Policy>::type cache_size;
  74. T powers[cache_size::value] = { 0, };
  75. unsigned n = 0;
  76. do{
  77. T binom = -static_cast<T>(n);
  78. T nested_sum = 1;
  79. if(n < sizeof(powers) / sizeof(powers[0]))
  80. powers[n] = pow(static_cast<T>(n + 1), -s);
  81. for(unsigned k = 1; k <= n; ++k)
  82. {
  83. T p;
  84. if(k < sizeof(powers) / sizeof(powers[0]))
  85. {
  86. p = powers[k];
  87. //p = pow(k + 1, -s);
  88. }
  89. else
  90. p = pow(static_cast<T>(k + 1), -s);
  91. nested_sum += binom * p;
  92. binom *= (k - static_cast<T>(n)) / (k + 1);
  93. }
  94. change = mult * nested_sum;
  95. sum += change;
  96. mult /= 2;
  97. ++n;
  98. }while(fabs(change / sum) > tools::epsilon<T>());
  99. return sum * 1 / -boost::math::powm1(T(2), sc);
  100. }
  101. //
  102. // Classical p-series:
  103. //
  104. template <class T>
  105. struct zeta_series2
  106. {
  107. typedef T result_type;
  108. zeta_series2(T _s) : s(-_s), k(1){}
  109. T operator()()
  110. {
  111. BOOST_MATH_STD_USING
  112. return pow(static_cast<T>(k++), s);
  113. }
  114. private:
  115. T s;
  116. unsigned k;
  117. };
  118. template <class T, class Policy>
  119. inline T zeta_series2_imp(T s, const Policy& pol)
  120. {
  121. std::uintmax_t max_iter = policies::get_max_series_iterations<Policy>();;
  122. zeta_series2<T> f(s);
  123. T result = tools::sum_series(
  124. f,
  125. policies::get_epsilon<T, Policy>(),
  126. max_iter);
  127. policies::check_series_iterations<T>("boost::math::zeta_series2<%1%>(%1%)", max_iter, pol);
  128. return result;
  129. }
  130. #endif
  131. template <class T, class Policy>
  132. T zeta_polynomial_series(T s, T sc, Policy const &)
  133. {
  134. //
  135. // This is algorithm 3 from:
  136. //
  137. // "An Efficient Algorithm for the Riemann Zeta Function", P. Borwein,
  138. // Canadian Mathematical Society, Conference Proceedings.
  139. // See: http://www.cecm.sfu.ca/personal/pborwein/PAPERS/P155.pdf
  140. //
  141. BOOST_MATH_STD_USING
  142. int n = itrunc(T(log(boost::math::tools::epsilon<T>()) / -2));
  143. T sum = 0; // LCOV_EXCL_LINE spurious miss as surrounding lines hit.
  144. T two_n = ldexp(T(1), n);
  145. int ej_sign = 1; // LCOV_EXCL_LINE spurious miss as surrounding lines hit.
  146. for(int j = 0; j < n; ++j)
  147. {
  148. sum += ej_sign * -two_n / pow(T(j + 1), s);
  149. ej_sign = -ej_sign;
  150. }
  151. T ej_sum = 1; // LCOV_EXCL_LINE spurious miss as surrounding lines hit.
  152. T ej_term = 1; // LCOV_EXCL_LINE spurious miss as surrounding lines hit.
  153. for(int j = n; j <= 2 * n - 1; ++j)
  154. {
  155. sum += ej_sign * (ej_sum - two_n) / pow(T(j + 1), s);
  156. ej_sign = -ej_sign;
  157. ej_term *= 2 * n - j;
  158. ej_term /= j - n + 1;
  159. ej_sum += ej_term; // LCOV_EXCL_LINE spurious miss as surrounding lines hit.
  160. }
  161. return -sum / (two_n * (-powm1(T(2), sc)));
  162. }
  163. //
  164. // MP only, verified as covered by the full tests:
  165. // LCOV_EXCL_START
  166. template <class T, class Policy>
  167. T zeta_imp_prec(T s, T sc, const Policy& pol, const std::integral_constant<int, 0>&)
  168. {
  169. BOOST_MATH_STD_USING
  170. T result;
  171. if(s >= policies::digits<T, Policy>())
  172. return 1;
  173. result = zeta_polynomial_series(s, sc, pol);
  174. #if 0
  175. // Old code archived for future reference:
  176. //
  177. // Only use power series if it will converge in 100
  178. // iterations or less: the more iterations it consumes
  179. // the slower convergence becomes so we have to be very
  180. // careful in it's usage.
  181. //
  182. if (s > -log(tools::epsilon<T>()) / 4.5)
  183. result = detail::zeta_series2_imp(s, pol);
  184. else
  185. result = detail::zeta_series_imp(s, sc, pol);
  186. #endif
  187. return result;
  188. }
  189. // LCOV_EXCL_STOP
  190. template <class T, class Policy>
  191. inline T zeta_imp_prec(T s, T sc, const Policy&, const std::integral_constant<int, 53>&)
  192. {
  193. BOOST_MATH_STD_USING
  194. T result;
  195. if(s < 1)
  196. {
  197. // Rational Approximation
  198. // Maximum Deviation Found: 2.020e-18
  199. // Expected Error Term: -2.020e-18
  200. // Max error found at double precision: 3.994987e-17
  201. // LCOV_EXCL_START
  202. static const T P[6] = {
  203. static_cast<T>(0.24339294433593750202L),
  204. static_cast<T>(-0.49092470516353571651L),
  205. static_cast<T>(0.0557616214776046784287L),
  206. static_cast<T>(-0.00320912498879085894856L),
  207. static_cast<T>(0.000451534528645796438704L),
  208. static_cast<T>(-0.933241270357061460782e-5L),
  209. };
  210. static const T Q[6] = {
  211. static_cast<T>(1L),
  212. static_cast<T>(-0.279960334310344432495L),
  213. static_cast<T>(0.0419676223309986037706L),
  214. static_cast<T>(-0.00413421406552171059003L),
  215. static_cast<T>(0.00024978985622317935355L),
  216. static_cast<T>(-0.101855788418564031874e-4L),
  217. };
  218. // LCOV_EXCL_STOP
  219. result = tools::evaluate_polynomial(P, sc) / tools::evaluate_polynomial(Q, sc);
  220. result -= 1.2433929443359375F;
  221. result += (sc);
  222. result /= (sc);
  223. }
  224. else if(s <= 2)
  225. {
  226. // Maximum Deviation Found: 9.007e-20
  227. // Expected Error Term: 9.007e-20
  228. // LCOV_EXCL_START
  229. static const T P[6] = {
  230. static_cast<T>(0.577215664901532860516L),
  231. static_cast<T>(0.243210646940107164097L),
  232. static_cast<T>(0.0417364673988216497593L),
  233. static_cast<T>(0.00390252087072843288378L),
  234. static_cast<T>(0.000249606367151877175456L),
  235. static_cast<T>(0.110108440976732897969e-4L),
  236. };
  237. static const T Q[6] = {
  238. static_cast<T>(1.0),
  239. static_cast<T>(0.295201277126631761737L),
  240. static_cast<T>(0.043460910607305495864L),
  241. static_cast<T>(0.00434930582085826330659L),
  242. static_cast<T>(0.000255784226140488490982L),
  243. static_cast<T>(0.10991819782396112081e-4L),
  244. };
  245. // LCOV_EXCL_STOP
  246. result = tools::evaluate_polynomial(P, T(-sc)) / tools::evaluate_polynomial(Q, T(-sc));
  247. result += 1 / (-sc);
  248. }
  249. else if(s <= 4)
  250. {
  251. // Maximum Deviation Found: 5.946e-22
  252. // Expected Error Term: -5.946e-22
  253. // LCOV_EXCL_START
  254. static const float Y = 0.6986598968505859375;
  255. static const T P[6] = {
  256. static_cast<T>(-0.0537258300023595030676L),
  257. static_cast<T>(0.0445163473292365591906L),
  258. static_cast<T>(0.0128677673534519952905L),
  259. static_cast<T>(0.00097541770457391752726L),
  260. static_cast<T>(0.769875101573654070925e-4L),
  261. static_cast<T>(0.328032510000383084155e-5L),
  262. };
  263. static const T Q[7] = {
  264. 1.0f,
  265. static_cast<T>(0.33383194553034051422L),
  266. static_cast<T>(0.0487798431291407621462L),
  267. static_cast<T>(0.00479039708573558490716L),
  268. static_cast<T>(0.000270776703956336357707L),
  269. static_cast<T>(0.106951867532057341359e-4L),
  270. static_cast<T>(0.236276623974978646399e-7L),
  271. };
  272. // LCOV_EXCL_STOP
  273. result = tools::evaluate_polynomial(P, T(s - 2)) / tools::evaluate_polynomial(Q, T(s - 2));
  274. result += Y + 1 / (-sc);
  275. }
  276. else if(s <= 7)
  277. {
  278. // Maximum Deviation Found: 2.955e-17
  279. // Expected Error Term: 2.955e-17
  280. // Max error found at double precision: 2.009135e-16
  281. // LCOV_EXCL_START
  282. static const T P[6] = {
  283. static_cast<T>(-2.49710190602259410021L),
  284. static_cast<T>(-2.60013301809475665334L),
  285. static_cast<T>(-0.939260435377109939261L),
  286. static_cast<T>(-0.138448617995741530935L),
  287. static_cast<T>(-0.00701721240549802377623L),
  288. static_cast<T>(-0.229257310594893932383e-4L),
  289. };
  290. static const T Q[9] = {
  291. 1.0f,
  292. static_cast<T>(0.706039025937745133628L),
  293. static_cast<T>(0.15739599649558626358L),
  294. static_cast<T>(0.0106117950976845084417L),
  295. static_cast<T>(-0.36910273311764618902e-4L),
  296. static_cast<T>(0.493409563927590008943e-5L),
  297. static_cast<T>(-0.234055487025287216506e-6L),
  298. static_cast<T>(0.718833729365459760664e-8L),
  299. static_cast<T>(-0.1129200113474947419e-9L),
  300. };
  301. // LCOV_EXCL_STOP
  302. result = tools::evaluate_polynomial(P, T(s - 4)) / tools::evaluate_polynomial(Q, T(s - 4));
  303. result = 1 + exp(result);
  304. }
  305. else if(s < 15)
  306. {
  307. // Maximum Deviation Found: 7.117e-16
  308. // Expected Error Term: 7.117e-16
  309. // Max error found at double precision: 9.387771e-16
  310. // LCOV_EXCL_START
  311. static const T P[7] = {
  312. static_cast<T>(-4.78558028495135619286L),
  313. static_cast<T>(-1.89197364881972536382L),
  314. static_cast<T>(-0.211407134874412820099L),
  315. static_cast<T>(-0.000189204758260076688518L),
  316. static_cast<T>(0.00115140923889178742086L),
  317. static_cast<T>(0.639949204213164496988e-4L),
  318. static_cast<T>(0.139348932445324888343e-5L),
  319. };
  320. static const T Q[9] = {
  321. 1.0f,
  322. static_cast<T>(0.244345337378188557777L),
  323. static_cast<T>(0.00873370754492288653669L),
  324. static_cast<T>(-0.00117592765334434471562L),
  325. static_cast<T>(-0.743743682899933180415e-4L),
  326. static_cast<T>(-0.21750464515767984778e-5L),
  327. static_cast<T>(0.471001264003076486547e-8L),
  328. static_cast<T>(-0.833378440625385520576e-10L),
  329. static_cast<T>(0.699841545204845636531e-12L),
  330. };
  331. // LCOV_EXCL_STOP
  332. result = tools::evaluate_polynomial(P, T(s - 7)) / tools::evaluate_polynomial(Q, T(s - 7));
  333. result = 1 + exp(result);
  334. }
  335. else if(s < 36)
  336. {
  337. // Max error in interpolated form: 1.668e-17
  338. // Max error found at long double precision: 1.669714e-17
  339. // LCOV_EXCL_START
  340. static const T P[8] = {
  341. static_cast<T>(-10.3948950573308896825L),
  342. static_cast<T>(-2.85827219671106697179L),
  343. static_cast<T>(-0.347728266539245787271L),
  344. static_cast<T>(-0.0251156064655346341766L),
  345. static_cast<T>(-0.00119459173416968685689L),
  346. static_cast<T>(-0.382529323507967522614e-4L),
  347. static_cast<T>(-0.785523633796723466968e-6L),
  348. static_cast<T>(-0.821465709095465524192e-8L),
  349. };
  350. static const T Q[10] = {
  351. 1.0f,
  352. static_cast<T>(0.208196333572671890965L),
  353. static_cast<T>(0.0195687657317205033485L),
  354. static_cast<T>(0.00111079638102485921877L),
  355. static_cast<T>(0.408507746266039256231e-4L),
  356. static_cast<T>(0.955561123065693483991e-6L),
  357. static_cast<T>(0.118507153474022900583e-7L),
  358. static_cast<T>(0.222609483627352615142e-14L),
  359. };
  360. // LCOV_EXCL_STOP
  361. result = tools::evaluate_polynomial(P, T(s - 15)) / tools::evaluate_polynomial(Q, T(s - 15));
  362. result = 1 + exp(result);
  363. }
  364. else
  365. {
  366. result = 1 + pow(T(2), -s);
  367. }
  368. return result;
  369. }
  370. template <class T, class Policy>
  371. T zeta_imp_prec(T s, T sc, const Policy&, const std::integral_constant<int, 64>&)
  372. {
  373. BOOST_MATH_STD_USING
  374. T result;
  375. if(s < 1)
  376. {
  377. // Rational Approximation
  378. // Maximum Deviation Found: 3.099e-20
  379. // Expected Error Term: 3.099e-20
  380. // Max error found at long double precision: 5.890498e-20
  381. // LCOV_EXCL_START
  382. static const T P[6] = {
  383. BOOST_MATH_BIG_CONSTANT(T, 64, 0.243392944335937499969),
  384. BOOST_MATH_BIG_CONSTANT(T, 64, -0.496837806864865688082),
  385. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0680008039723709987107),
  386. BOOST_MATH_BIG_CONSTANT(T, 64, -0.00511620413006619942112),
  387. BOOST_MATH_BIG_CONSTANT(T, 64, 0.000455369899250053003335),
  388. BOOST_MATH_BIG_CONSTANT(T, 64, -0.279496685273033761927e-4),
  389. };
  390. static const T Q[7] = {
  391. BOOST_MATH_BIG_CONSTANT(T, 64, 1.0),
  392. BOOST_MATH_BIG_CONSTANT(T, 64, -0.30425480068225790522),
  393. BOOST_MATH_BIG_CONSTANT(T, 64, 0.050052748580371598736),
  394. BOOST_MATH_BIG_CONSTANT(T, 64, -0.00519355671064700627862),
  395. BOOST_MATH_BIG_CONSTANT(T, 64, 0.000360623385771198350257),
  396. BOOST_MATH_BIG_CONSTANT(T, 64, -0.159600883054550987633e-4),
  397. BOOST_MATH_BIG_CONSTANT(T, 64, 0.339770279812410586032e-6),
  398. };
  399. // LCOV_EXCL_STOP
  400. result = tools::evaluate_polynomial(P, sc) / tools::evaluate_polynomial(Q, sc);
  401. result -= 1.2433929443359375F;
  402. result += (sc);
  403. result /= (sc);
  404. }
  405. else if(s <= 2)
  406. {
  407. // Maximum Deviation Found: 1.059e-21
  408. // Expected Error Term: 1.059e-21
  409. // Max error found at long double precision: 1.626303e-19
  410. // LCOV_EXCL_START
  411. static const T P[6] = {
  412. BOOST_MATH_BIG_CONSTANT(T, 64, 0.577215664901532860605),
  413. BOOST_MATH_BIG_CONSTANT(T, 64, 0.222537368917162139445),
  414. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0356286324033215682729),
  415. BOOST_MATH_BIG_CONSTANT(T, 64, 0.00304465292366350081446),
  416. BOOST_MATH_BIG_CONSTANT(T, 64, 0.000178102511649069421904),
  417. BOOST_MATH_BIG_CONSTANT(T, 64, 0.700867470265983665042e-5),
  418. };
  419. static const T Q[7] = {
  420. BOOST_MATH_BIG_CONSTANT(T, 64, 1.0),
  421. BOOST_MATH_BIG_CONSTANT(T, 64, 0.259385759149531030085),
  422. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0373974962106091316854),
  423. BOOST_MATH_BIG_CONSTANT(T, 64, 0.00332735159183332820617),
  424. BOOST_MATH_BIG_CONSTANT(T, 64, 0.000188690420706998606469),
  425. BOOST_MATH_BIG_CONSTANT(T, 64, 0.635994377921861930071e-5),
  426. BOOST_MATH_BIG_CONSTANT(T, 64, 0.226583954978371199405e-7),
  427. };
  428. // LCOV_EXCL_STOP
  429. result = tools::evaluate_polynomial(P, T(-sc)) / tools::evaluate_polynomial(Q, T(-sc));
  430. result += 1 / (-sc);
  431. }
  432. else if(s <= 4)
  433. {
  434. // Maximum Deviation Found: 5.946e-22
  435. // Expected Error Term: -5.946e-22
  436. // LCOV_EXCL_START
  437. static const float Y = 0.6986598968505859375;
  438. static const T P[7] = {
  439. BOOST_MATH_BIG_CONSTANT(T, 64, -0.053725830002359501027),
  440. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0470551187571475844778),
  441. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0101339410415759517471),
  442. BOOST_MATH_BIG_CONSTANT(T, 64, 0.00100240326666092854528),
  443. BOOST_MATH_BIG_CONSTANT(T, 64, 0.685027119098122814867e-4),
  444. BOOST_MATH_BIG_CONSTANT(T, 64, 0.390972820219765942117e-5),
  445. BOOST_MATH_BIG_CONSTANT(T, 64, 0.540319769113543934483e-7),
  446. };
  447. static const T Q[8] = {
  448. BOOST_MATH_BIG_CONSTANT(T, 64, 1.0),
  449. BOOST_MATH_BIG_CONSTANT(T, 64, 0.286577739726542730421),
  450. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0447355811517733225843),
  451. BOOST_MATH_BIG_CONSTANT(T, 64, 0.00430125107610252363302),
  452. BOOST_MATH_BIG_CONSTANT(T, 64, 0.000284956969089786662045),
  453. BOOST_MATH_BIG_CONSTANT(T, 64, 0.116188101609848411329e-4),
  454. BOOST_MATH_BIG_CONSTANT(T, 64, 0.278090318191657278204e-6),
  455. BOOST_MATH_BIG_CONSTANT(T, 64, -0.19683620233222028478e-8),
  456. };
  457. // LCOV_EXCL_STOP
  458. result = tools::evaluate_polynomial(P, T(s - 2)) / tools::evaluate_polynomial(Q, T(s - 2));
  459. result += Y + 1 / (-sc);
  460. }
  461. else if(s <= 7)
  462. {
  463. // Max error found at long double precision: 8.132216e-19
  464. // LCOV_EXCL_START
  465. static const T P[8] = {
  466. BOOST_MATH_BIG_CONSTANT(T, 64, -2.49710190602259407065),
  467. BOOST_MATH_BIG_CONSTANT(T, 64, -3.36664913245960625334),
  468. BOOST_MATH_BIG_CONSTANT(T, 64, -1.77180020623777595452),
  469. BOOST_MATH_BIG_CONSTANT(T, 64, -0.464717885249654313933),
  470. BOOST_MATH_BIG_CONSTANT(T, 64, -0.0643694921293579472583),
  471. BOOST_MATH_BIG_CONSTANT(T, 64, -0.00464265386202805715487),
  472. BOOST_MATH_BIG_CONSTANT(T, 64, -0.000165556579779704340166),
  473. BOOST_MATH_BIG_CONSTANT(T, 64, -0.252884970740994069582e-5),
  474. };
  475. static const T Q[9] = {
  476. BOOST_MATH_BIG_CONSTANT(T, 64, 1.0),
  477. BOOST_MATH_BIG_CONSTANT(T, 64, 1.01300131390690459085),
  478. BOOST_MATH_BIG_CONSTANT(T, 64, 0.387898115758643503827),
  479. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0695071490045701135188),
  480. BOOST_MATH_BIG_CONSTANT(T, 64, 0.00586908595251442839291),
  481. BOOST_MATH_BIG_CONSTANT(T, 64, 0.000217752974064612188616),
  482. BOOST_MATH_BIG_CONSTANT(T, 64, 0.397626583349419011731e-5),
  483. BOOST_MATH_BIG_CONSTANT(T, 64, -0.927884739284359700764e-8),
  484. BOOST_MATH_BIG_CONSTANT(T, 64, 0.119810501805618894381e-9),
  485. };
  486. // LCOV_EXCL_STOP
  487. result = tools::evaluate_polynomial(P, T(s - 4)) / tools::evaluate_polynomial(Q, T(s - 4));
  488. result = 1 + exp(result);
  489. }
  490. else if(s < 15)
  491. {
  492. // Max error in interpolated form: 1.133e-18
  493. // Max error found at long double precision: 2.183198e-18
  494. // LCOV_EXCL_START
  495. static const T P[9] = {
  496. BOOST_MATH_BIG_CONSTANT(T, 64, -4.78558028495135548083),
  497. BOOST_MATH_BIG_CONSTANT(T, 64, -3.23873322238609358947),
  498. BOOST_MATH_BIG_CONSTANT(T, 64, -0.892338582881021799922),
  499. BOOST_MATH_BIG_CONSTANT(T, 64, -0.131326296217965913809),
  500. BOOST_MATH_BIG_CONSTANT(T, 64, -0.0115651591773783712996),
  501. BOOST_MATH_BIG_CONSTANT(T, 64, -0.000657728968362695775205),
  502. BOOST_MATH_BIG_CONSTANT(T, 64, -0.252051328129449973047e-4),
  503. BOOST_MATH_BIG_CONSTANT(T, 64, -0.626503445372641798925e-6),
  504. BOOST_MATH_BIG_CONSTANT(T, 64, -0.815696314790853893484e-8),
  505. };
  506. static const T Q[9] = {
  507. BOOST_MATH_BIG_CONSTANT(T, 64, 1.0),
  508. BOOST_MATH_BIG_CONSTANT(T, 64, 0.525765665400123515036),
  509. BOOST_MATH_BIG_CONSTANT(T, 64, 0.10852641753657122787),
  510. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0115669945375362045249),
  511. BOOST_MATH_BIG_CONSTANT(T, 64, 0.000732896513858274091966),
  512. BOOST_MATH_BIG_CONSTANT(T, 64, 0.30683952282420248448e-4),
  513. BOOST_MATH_BIG_CONSTANT(T, 64, 0.819649214609633126119e-6),
  514. BOOST_MATH_BIG_CONSTANT(T, 64, 0.117957556472335968146e-7),
  515. BOOST_MATH_BIG_CONSTANT(T, 64, -0.193432300973017671137e-12),
  516. };
  517. // LCOV_EXCL_STOP
  518. result = tools::evaluate_polynomial(P, T(s - 7)) / tools::evaluate_polynomial(Q, T(s - 7));
  519. result = 1 + exp(result);
  520. }
  521. else if(s < 42)
  522. {
  523. // Max error in interpolated form: 1.668e-17
  524. // Max error found at long double precision: 1.669714e-17
  525. // LCOV_EXCL_START
  526. static const T P[9] = {
  527. BOOST_MATH_BIG_CONSTANT(T, 64, -10.3948950573308861781),
  528. BOOST_MATH_BIG_CONSTANT(T, 64, -2.82646012777913950108),
  529. BOOST_MATH_BIG_CONSTANT(T, 64, -0.342144362739570333665),
  530. BOOST_MATH_BIG_CONSTANT(T, 64, -0.0249285145498722647472),
  531. BOOST_MATH_BIG_CONSTANT(T, 64, -0.00122493108848097114118),
  532. BOOST_MATH_BIG_CONSTANT(T, 64, -0.423055371192592850196e-4),
  533. BOOST_MATH_BIG_CONSTANT(T, 64, -0.1025215577185967488e-5),
  534. BOOST_MATH_BIG_CONSTANT(T, 64, -0.165096762663509467061e-7),
  535. BOOST_MATH_BIG_CONSTANT(T, 64, -0.145392555873022044329e-9),
  536. };
  537. static const T Q[10] = {
  538. BOOST_MATH_BIG_CONSTANT(T, 64, 1.0),
  539. BOOST_MATH_BIG_CONSTANT(T, 64, 0.205135978585281988052),
  540. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0192359357875879453602),
  541. BOOST_MATH_BIG_CONSTANT(T, 64, 0.00111496452029715514119),
  542. BOOST_MATH_BIG_CONSTANT(T, 64, 0.434928449016693986857e-4),
  543. BOOST_MATH_BIG_CONSTANT(T, 64, 0.116911068726610725891e-5),
  544. BOOST_MATH_BIG_CONSTANT(T, 64, 0.206704342290235237475e-7),
  545. BOOST_MATH_BIG_CONSTANT(T, 64, 0.209772836100827647474e-9),
  546. BOOST_MATH_BIG_CONSTANT(T, 64, -0.939798249922234703384e-16),
  547. BOOST_MATH_BIG_CONSTANT(T, 64, 0.264584017421245080294e-18),
  548. };
  549. // LCOV_EXCL_STOP
  550. result = tools::evaluate_polynomial(P, T(s - 15)) / tools::evaluate_polynomial(Q, T(s - 15));
  551. result = 1 + exp(result);
  552. }
  553. else
  554. {
  555. result = 1 + pow(T(2), -s);
  556. }
  557. return result;
  558. }
  559. template <class T, class Policy>
  560. T zeta_imp_prec(T s, T sc, const Policy&, const std::integral_constant<int, 113>&)
  561. {
  562. BOOST_MATH_STD_USING
  563. T result;
  564. if(s < 1)
  565. {
  566. // Rational Approximation
  567. // Maximum Deviation Found: 9.493e-37
  568. // Expected Error Term: 9.492e-37
  569. // Max error found at long double precision: 7.281332e-31
  570. // LCOV_EXCL_START
  571. static const T P[10] = {
  572. BOOST_MATH_BIG_CONSTANT(T, 113, -1.0),
  573. BOOST_MATH_BIG_CONSTANT(T, 113, -0.0353008629988648122808504280990313668),
  574. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0107795651204927743049369868548706909),
  575. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000523961870530500751114866884685172975),
  576. BOOST_MATH_BIG_CONSTANT(T, 113, -0.661805838304910731947595897966487515e-4),
  577. BOOST_MATH_BIG_CONSTANT(T, 113, -0.658932670403818558510656304189164638e-5),
  578. BOOST_MATH_BIG_CONSTANT(T, 113, -0.103437265642266106533814021041010453e-6),
  579. BOOST_MATH_BIG_CONSTANT(T, 113, 0.116818787212666457105375746642927737e-7),
  580. BOOST_MATH_BIG_CONSTANT(T, 113, 0.660690993901506912123512551294239036e-9),
  581. BOOST_MATH_BIG_CONSTANT(T, 113, 0.113103113698388531428914333768142527e-10),
  582. };
  583. static const T Q[11] = {
  584. BOOST_MATH_BIG_CONSTANT(T, 113, 1.0),
  585. BOOST_MATH_BIG_CONSTANT(T, 113, -0.387483472099602327112637481818565459),
  586. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0802265315091063135271497708694776875),
  587. BOOST_MATH_BIG_CONSTANT(T, 113, -0.0110727276164171919280036408995078164),
  588. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00112552716946286252000434849173787243),
  589. BOOST_MATH_BIG_CONSTANT(T, 113, -0.874554160748626916455655180296834352e-4),
  590. BOOST_MATH_BIG_CONSTANT(T, 113, 0.530097847491828379568636739662278322e-5),
  591. BOOST_MATH_BIG_CONSTANT(T, 113, -0.248461553590496154705565904497247452e-6),
  592. BOOST_MATH_BIG_CONSTANT(T, 113, 0.881834921354014787309644951507523899e-8),
  593. BOOST_MATH_BIG_CONSTANT(T, 113, -0.217062446168217797598596496310953025e-9),
  594. BOOST_MATH_BIG_CONSTANT(T, 113, 0.315823200002384492377987848307151168e-11),
  595. };
  596. // LCOV_EXCL_STOP
  597. result = tools::evaluate_polynomial(P, sc) / tools::evaluate_polynomial(Q, sc);
  598. result += (sc);
  599. result /= (sc);
  600. }
  601. else if(s <= 2)
  602. {
  603. // Maximum Deviation Found: 1.616e-37
  604. // Expected Error Term: -1.615e-37
  605. // LCOV_EXCL_START
  606. static const T P[10] = {
  607. BOOST_MATH_BIG_CONSTANT(T, 113, 0.577215664901532860606512090082402431),
  608. BOOST_MATH_BIG_CONSTANT(T, 113, 0.255597968739771510415479842335906308),
  609. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0494056503552807274142218876983542205),
  610. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00551372778611700965268920983472292325),
  611. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00043667616723970574871427830895192731),
  612. BOOST_MATH_BIG_CONSTANT(T, 113, 0.268562259154821957743669387915239528e-4),
  613. BOOST_MATH_BIG_CONSTANT(T, 113, 0.109249633923016310141743084480436612e-5),
  614. BOOST_MATH_BIG_CONSTANT(T, 113, 0.273895554345300227466534378753023924e-7),
  615. BOOST_MATH_BIG_CONSTANT(T, 113, 0.583103205551702720149237384027795038e-9),
  616. BOOST_MATH_BIG_CONSTANT(T, 113, -0.835774625259919268768735944711219256e-11),
  617. };
  618. static const T Q[11] = {
  619. BOOST_MATH_BIG_CONSTANT(T, 113, 1.0),
  620. BOOST_MATH_BIG_CONSTANT(T, 113, 0.316661751179735502065583176348292881),
  621. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0540401806533507064453851182728635272),
  622. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00598621274107420237785899476374043797),
  623. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000474907812321704156213038740142079615),
  624. BOOST_MATH_BIG_CONSTANT(T, 113, 0.272125421722314389581695715835862418e-4),
  625. BOOST_MATH_BIG_CONSTANT(T, 113, 0.112649552156479800925522445229212933e-5),
  626. BOOST_MATH_BIG_CONSTANT(T, 113, 0.301838975502992622733000078063330461e-7),
  627. BOOST_MATH_BIG_CONSTANT(T, 113, 0.422960728687211282539769943184270106e-9),
  628. BOOST_MATH_BIG_CONSTANT(T, 113, -0.377105263588822468076813329270698909e-11),
  629. BOOST_MATH_BIG_CONSTANT(T, 113, -0.581926559304525152432462127383600681e-13),
  630. };
  631. // LCOV_EXCL_STOP
  632. result = tools::evaluate_polynomial(P, T(-sc)) / tools::evaluate_polynomial(Q, T(-sc));
  633. result += 1 / (-sc);
  634. }
  635. else if(s <= 4)
  636. {
  637. // Maximum Deviation Found: 1.891e-36
  638. // Expected Error Term: -1.891e-36
  639. // Max error found: 2.171527e-35
  640. // LCOV_EXCL_START
  641. static const float Y = 0.6986598968505859375;
  642. static const T P[11] = {
  643. BOOST_MATH_BIG_CONSTANT(T, 113, -0.0537258300023595010275848333539748089),
  644. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0429086930802630159457448174466342553),
  645. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0136148228754303412510213395034056857),
  646. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00190231601036042925183751238033763915),
  647. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000186880390916311438818302549192456581),
  648. BOOST_MATH_BIG_CONSTANT(T, 113, 0.145347370745893262394287982691323657e-4),
  649. BOOST_MATH_BIG_CONSTANT(T, 113, 0.805843276446813106414036600485884885e-6),
  650. BOOST_MATH_BIG_CONSTANT(T, 113, 0.340818159286739137503297172091882574e-7),
  651. BOOST_MATH_BIG_CONSTANT(T, 113, 0.115762357488748996526167305116837246e-8),
  652. BOOST_MATH_BIG_CONSTANT(T, 113, 0.231904754577648077579913403645767214e-10),
  653. BOOST_MATH_BIG_CONSTANT(T, 113, 0.340169592866058506675897646629036044e-12),
  654. };
  655. static const T Q[12] = {
  656. BOOST_MATH_BIG_CONSTANT(T, 113, 1.0),
  657. BOOST_MATH_BIG_CONSTANT(T, 113, 0.363755247765087100018556983050520554),
  658. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0696581979014242539385695131258321598),
  659. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00882208914484611029571547753782014817),
  660. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000815405623261946661762236085660996718),
  661. BOOST_MATH_BIG_CONSTANT(T, 113, 0.571366167062457197282642344940445452e-4),
  662. BOOST_MATH_BIG_CONSTANT(T, 113, 0.309278269271853502353954062051797838e-5),
  663. BOOST_MATH_BIG_CONSTANT(T, 113, 0.12822982083479010834070516053794262e-6),
  664. BOOST_MATH_BIG_CONSTANT(T, 113, 0.397876357325018976733953479182110033e-8),
  665. BOOST_MATH_BIG_CONSTANT(T, 113, 0.8484432107648683277598472295289279e-10),
  666. BOOST_MATH_BIG_CONSTANT(T, 113, 0.105677416606909614301995218444080615e-11),
  667. BOOST_MATH_BIG_CONSTANT(T, 113, 0.547223964564003701979951154093005354e-15),
  668. };
  669. // LCOV_EXCL_STOP
  670. result = tools::evaluate_polynomial(P, T(s - 2)) / tools::evaluate_polynomial(Q, T(s - 2));
  671. result += Y + 1 / (-sc);
  672. }
  673. else if(s <= 6)
  674. {
  675. // Max error in interpolated form: 1.510e-37
  676. // Max error found at long double precision: 2.769266e-34
  677. // LCOV_EXCL_START
  678. static const T Y = 3.28348541259765625F;
  679. static const T P[13] = {
  680. BOOST_MATH_BIG_CONSTANT(T, 113, 0.786383506575062179339611614117697622),
  681. BOOST_MATH_BIG_CONSTANT(T, 113, 0.495766593395271370974685959652073976),
  682. BOOST_MATH_BIG_CONSTANT(T, 113, -0.409116737851754766422360889037532228),
  683. BOOST_MATH_BIG_CONSTANT(T, 113, -0.57340744006238263817895456842655987),
  684. BOOST_MATH_BIG_CONSTANT(T, 113, -0.280479899797421910694892949057963111),
  685. BOOST_MATH_BIG_CONSTANT(T, 113, -0.0753148409447590257157585696212649869),
  686. BOOST_MATH_BIG_CONSTANT(T, 113, -0.0122934003684672788499099362823748632),
  687. BOOST_MATH_BIG_CONSTANT(T, 113, -0.00126148398446193639247961370266962927),
  688. BOOST_MATH_BIG_CONSTANT(T, 113, -0.828465038179772939844657040917364896e-4),
  689. BOOST_MATH_BIG_CONSTANT(T, 113, -0.361008916706050977143208468690645684e-5),
  690. BOOST_MATH_BIG_CONSTANT(T, 113, -0.109879825497910544424797771195928112e-6),
  691. BOOST_MATH_BIG_CONSTANT(T, 113, -0.214539416789686920918063075528797059e-8),
  692. BOOST_MATH_BIG_CONSTANT(T, 113, -0.15090220092460596872172844424267351e-10),
  693. };
  694. static const T Q[14] = {
  695. BOOST_MATH_BIG_CONSTANT(T, 113, 1.0),
  696. BOOST_MATH_BIG_CONSTANT(T, 113, 1.69490865837142338462982225731926485),
  697. BOOST_MATH_BIG_CONSTANT(T, 113, 1.22697696630994080733321401255942464),
  698. BOOST_MATH_BIG_CONSTANT(T, 113, 0.495409420862526540074366618006341533),
  699. BOOST_MATH_BIG_CONSTANT(T, 113, 0.122368084916843823462872905024259633),
  700. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0191412993625268971656513890888208623),
  701. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00191401538628980617753082598351559642),
  702. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000123318142456272424148930280876444459),
  703. BOOST_MATH_BIG_CONSTANT(T, 113, 0.531945488232526067889835342277595709e-5),
  704. BOOST_MATH_BIG_CONSTANT(T, 113, 0.161843184071894368337068779669116236e-6),
  705. BOOST_MATH_BIG_CONSTANT(T, 113, 0.305796079600152506743828859577462778e-8),
  706. BOOST_MATH_BIG_CONSTANT(T, 113, 0.233582592298450202680170811044408894e-10),
  707. BOOST_MATH_BIG_CONSTANT(T, 113, -0.275363878344548055574209713637734269e-13),
  708. BOOST_MATH_BIG_CONSTANT(T, 113, 0.221564186807357535475441900517843892e-15),
  709. };
  710. // LCOV_EXCL_STOP
  711. result = tools::evaluate_polynomial(P, T(s - 4)) / tools::evaluate_polynomial(Q, T(s - 4));
  712. result -= Y;
  713. result = 1 + exp(result);
  714. }
  715. else if(s < 10)
  716. {
  717. // Max error in interpolated form: 1.999e-34
  718. // Max error found at long double precision: 2.156186e-33
  719. // LCOV_EXCL_START
  720. static const T P[13] = {
  721. BOOST_MATH_BIG_CONSTANT(T, 113, -4.0545627381873738086704293881227365),
  722. BOOST_MATH_BIG_CONSTANT(T, 113, -4.70088348734699134347906176097717782),
  723. BOOST_MATH_BIG_CONSTANT(T, 113, -2.36921550900925512951976617607678789),
  724. BOOST_MATH_BIG_CONSTANT(T, 113, -0.684322583796369508367726293719322866),
  725. BOOST_MATH_BIG_CONSTANT(T, 113, -0.126026534540165129870721937592996324),
  726. BOOST_MATH_BIG_CONSTANT(T, 113, -0.015636903921778316147260572008619549),
  727. BOOST_MATH_BIG_CONSTANT(T, 113, -0.00135442294754728549644376325814460807),
  728. BOOST_MATH_BIG_CONSTANT(T, 113, -0.842793965853572134365031384646117061e-4),
  729. BOOST_MATH_BIG_CONSTANT(T, 113, -0.385602133791111663372015460784978351e-5),
  730. BOOST_MATH_BIG_CONSTANT(T, 113, -0.130458500394692067189883214401478539e-6),
  731. BOOST_MATH_BIG_CONSTANT(T, 113, -0.315861074947230418778143153383660035e-8),
  732. BOOST_MATH_BIG_CONSTANT(T, 113, -0.500334720512030826996373077844707164e-10),
  733. BOOST_MATH_BIG_CONSTANT(T, 113, -0.420204769185233365849253969097184005e-12),
  734. };
  735. static const T Q[14] = {
  736. BOOST_MATH_BIG_CONSTANT(T, 113, 1.0),
  737. BOOST_MATH_BIG_CONSTANT(T, 113, 0.97663511666410096104783358493318814),
  738. BOOST_MATH_BIG_CONSTANT(T, 113, 0.40878780231201806504987368939673249),
  739. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0963890666609396058945084107597727252),
  740. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0142207619090854604824116070866614505),
  741. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00139010220902667918476773423995750877),
  742. BOOST_MATH_BIG_CONSTANT(T, 113, 0.940669540194694997889636696089994734e-4),
  743. BOOST_MATH_BIG_CONSTANT(T, 113, 0.458220848507517004399292480807026602e-5),
  744. BOOST_MATH_BIG_CONSTANT(T, 113, 0.16345521617741789012782420625435495e-6),
  745. BOOST_MATH_BIG_CONSTANT(T, 113, 0.414007452533083304371566316901024114e-8),
  746. BOOST_MATH_BIG_CONSTANT(T, 113, 0.68701473543366328016953742622661377e-10),
  747. BOOST_MATH_BIG_CONSTANT(T, 113, 0.603461891080716585087883971886075863e-12),
  748. BOOST_MATH_BIG_CONSTANT(T, 113, 0.294670713571839023181857795866134957e-16),
  749. BOOST_MATH_BIG_CONSTANT(T, 113, -0.147003914536437243143096875069813451e-18),
  750. };
  751. // LCOV_EXCL_STOP
  752. result = tools::evaluate_polynomial(P, T(s - 6)) / tools::evaluate_polynomial(Q, T(s - 6));
  753. result = 1 + exp(result);
  754. }
  755. else if(s < 17)
  756. {
  757. // Max error in interpolated form: 1.641e-32
  758. // Max error found at long double precision: 1.696121e-32
  759. // LCOV_EXCL_START
  760. static const T P[13] = {
  761. BOOST_MATH_BIG_CONSTANT(T, 113, -6.91319491921722925920883787894829678),
  762. BOOST_MATH_BIG_CONSTANT(T, 113, -3.65491257639481960248690596951049048),
  763. BOOST_MATH_BIG_CONSTANT(T, 113, -0.813557553449954526442644544105257881),
  764. BOOST_MATH_BIG_CONSTANT(T, 113, -0.0994317301685870959473658713841138083),
  765. BOOST_MATH_BIG_CONSTANT(T, 113, -0.00726896610245676520248617014211734906),
  766. BOOST_MATH_BIG_CONSTANT(T, 113, -0.000317253318715075854811266230916762929),
  767. BOOST_MATH_BIG_CONSTANT(T, 113, -0.66851422826636750855184211580127133e-5),
  768. BOOST_MATH_BIG_CONSTANT(T, 113, 0.879464154730985406003332577806849971e-7),
  769. BOOST_MATH_BIG_CONSTANT(T, 113, 0.113838903158254250631678791998294628e-7),
  770. BOOST_MATH_BIG_CONSTANT(T, 113, 0.379184410304927316385211327537817583e-9),
  771. BOOST_MATH_BIG_CONSTANT(T, 113, 0.612992858643904887150527613446403867e-11),
  772. BOOST_MATH_BIG_CONSTANT(T, 113, 0.347873737198164757035457841688594788e-13),
  773. BOOST_MATH_BIG_CONSTANT(T, 113, -0.289187187441625868404494665572279364e-15),
  774. };
  775. static const T Q[14] = {
  776. BOOST_MATH_BIG_CONSTANT(T, 113, 1.0),
  777. BOOST_MATH_BIG_CONSTANT(T, 113, 0.427310044448071818775721584949868806),
  778. BOOST_MATH_BIG_CONSTANT(T, 113, 0.074602514873055756201435421385243062),
  779. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00688651562174480772901425121653945942),
  780. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000360174847635115036351323894321880445),
  781. BOOST_MATH_BIG_CONSTANT(T, 113, 0.973556847713307543918865405758248777e-5),
  782. BOOST_MATH_BIG_CONSTANT(T, 113, -0.853455848314516117964634714780874197e-8),
  783. BOOST_MATH_BIG_CONSTANT(T, 113, -0.118203513654855112421673192194622826e-7),
  784. BOOST_MATH_BIG_CONSTANT(T, 113, -0.462521662511754117095006543363328159e-9),
  785. BOOST_MATH_BIG_CONSTANT(T, 113, -0.834212591919475633107355719369463143e-11),
  786. BOOST_MATH_BIG_CONSTANT(T, 113, -0.5354594751002702935740220218582929e-13),
  787. BOOST_MATH_BIG_CONSTANT(T, 113, 0.406451690742991192964889603000756203e-15),
  788. BOOST_MATH_BIG_CONSTANT(T, 113, 0.887948682401000153828241615760146728e-19),
  789. BOOST_MATH_BIG_CONSTANT(T, 113, -0.34980761098820347103967203948619072e-21),
  790. };
  791. // LCOV_EXCL_STOP
  792. result = tools::evaluate_polynomial(P, T(s - 10)) / tools::evaluate_polynomial(Q, T(s - 10));
  793. result = 1 + exp(result);
  794. }
  795. else if(s < 30)
  796. {
  797. // Max error in interpolated form: 1.563e-31
  798. // Max error found at long double precision: 1.562725e-31
  799. // LCOV_EXCL_START
  800. static const T P[13] = {
  801. BOOST_MATH_BIG_CONSTANT(T, 113, -11.7824798233959252791987402769438322),
  802. BOOST_MATH_BIG_CONSTANT(T, 113, -4.36131215284987731928174218354118102),
  803. BOOST_MATH_BIG_CONSTANT(T, 113, -0.732260980060982349410898496846972204),
  804. BOOST_MATH_BIG_CONSTANT(T, 113, -0.0744985185694913074484248803015717388),
  805. BOOST_MATH_BIG_CONSTANT(T, 113, -0.00517228281320594683022294996292250527),
  806. BOOST_MATH_BIG_CONSTANT(T, 113, -0.000260897206152101522569969046299309939),
  807. BOOST_MATH_BIG_CONSTANT(T, 113, -0.989553462123121764865178453128769948e-5),
  808. BOOST_MATH_BIG_CONSTANT(T, 113, -0.286916799741891410827712096608826167e-6),
  809. BOOST_MATH_BIG_CONSTANT(T, 113, -0.637262477796046963617949532211619729e-8),
  810. BOOST_MATH_BIG_CONSTANT(T, 113, -0.106796831465628373325491288787760494e-9),
  811. BOOST_MATH_BIG_CONSTANT(T, 113, -0.129343095511091870860498356205376823e-11),
  812. BOOST_MATH_BIG_CONSTANT(T, 113, -0.102397936697965977221267881716672084e-13),
  813. BOOST_MATH_BIG_CONSTANT(T, 113, -0.402663128248642002351627980255756363e-16),
  814. };
  815. static const T Q[14] = {
  816. BOOST_MATH_BIG_CONSTANT(T, 113, 1.0),
  817. BOOST_MATH_BIG_CONSTANT(T, 113, 0.311288325355705609096155335186466508),
  818. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0438318468940415543546769437752132748),
  819. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00374396349183199548610264222242269536),
  820. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000218707451200585197339671707189281302),
  821. BOOST_MATH_BIG_CONSTANT(T, 113, 0.927578767487930747532953583797351219e-5),
  822. BOOST_MATH_BIG_CONSTANT(T, 113, 0.294145760625753561951137473484889639e-6),
  823. BOOST_MATH_BIG_CONSTANT(T, 113, 0.704618586690874460082739479535985395e-8),
  824. BOOST_MATH_BIG_CONSTANT(T, 113, 0.126333332872897336219649130062221257e-9),
  825. BOOST_MATH_BIG_CONSTANT(T, 113, 0.16317315713773503718315435769352765e-11),
  826. BOOST_MATH_BIG_CONSTANT(T, 113, 0.137846712823719515148344938160275695e-13),
  827. BOOST_MATH_BIG_CONSTANT(T, 113, 0.580975420554224366450994232723910583e-16),
  828. BOOST_MATH_BIG_CONSTANT(T, 113, -0.291354445847552426900293580511392459e-22),
  829. BOOST_MATH_BIG_CONSTANT(T, 113, 0.73614324724785855925025452085443636e-25),
  830. };
  831. // LCOV_EXCL_STOP
  832. result = tools::evaluate_polynomial(P, T(s - 17)) / tools::evaluate_polynomial(Q, T(s - 17));
  833. result = 1 + exp(result);
  834. }
  835. else if(s < 74)
  836. {
  837. // Max error in interpolated form: 2.311e-27
  838. // Max error found at long double precision: 2.297544e-27
  839. // LCOV_EXCL_START
  840. static const T P[14] = {
  841. BOOST_MATH_BIG_CONSTANT(T, 113, -20.7944102007844314586649688802236072),
  842. BOOST_MATH_BIG_CONSTANT(T, 113, -4.95759941987499442499908748130192187),
  843. BOOST_MATH_BIG_CONSTANT(T, 113, -0.563290752832461751889194629200298688),
  844. BOOST_MATH_BIG_CONSTANT(T, 113, -0.0406197001137935911912457120706122877),
  845. BOOST_MATH_BIG_CONSTANT(T, 113, -0.0020846534789473022216888863613422293),
  846. BOOST_MATH_BIG_CONSTANT(T, 113, -0.808095978462109173749395599401375667e-4),
  847. BOOST_MATH_BIG_CONSTANT(T, 113, -0.244706022206249301640890603610060959e-5),
  848. BOOST_MATH_BIG_CONSTANT(T, 113, -0.589477682919645930544382616501666572e-7),
  849. BOOST_MATH_BIG_CONSTANT(T, 113, -0.113699573675553496343617442433027672e-8),
  850. BOOST_MATH_BIG_CONSTANT(T, 113, -0.174767860183598149649901223128011828e-10),
  851. BOOST_MATH_BIG_CONSTANT(T, 113, -0.210051620306761367764549971980026474e-12),
  852. BOOST_MATH_BIG_CONSTANT(T, 113, -0.189187969537370950337212675466400599e-14),
  853. BOOST_MATH_BIG_CONSTANT(T, 113, -0.116313253429564048145641663778121898e-16),
  854. BOOST_MATH_BIG_CONSTANT(T, 113, -0.376708747782400769427057630528578187e-19),
  855. };
  856. static const T Q[16] = {
  857. BOOST_MATH_BIG_CONSTANT(T, 113, 1.0),
  858. BOOST_MATH_BIG_CONSTANT(T, 113, 0.205076752981410805177554569784219717),
  859. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0202526722696670378999575738524540269),
  860. BOOST_MATH_BIG_CONSTANT(T, 113, 0.001278305290005994980069466658219057),
  861. BOOST_MATH_BIG_CONSTANT(T, 113, 0.576404779858501791742255670403304787e-4),
  862. BOOST_MATH_BIG_CONSTANT(T, 113, 0.196477049872253010859712483984252067e-5),
  863. BOOST_MATH_BIG_CONSTANT(T, 113, 0.521863830500876189501054079974475762e-7),
  864. BOOST_MATH_BIG_CONSTANT(T, 113, 0.109524209196868135198775445228552059e-8),
  865. BOOST_MATH_BIG_CONSTANT(T, 113, 0.181698713448644481083966260949267825e-10),
  866. BOOST_MATH_BIG_CONSTANT(T, 113, 0.234793316975091282090312036524695562e-12),
  867. BOOST_MATH_BIG_CONSTANT(T, 113, 0.227490441461460571047545264251399048e-14),
  868. BOOST_MATH_BIG_CONSTANT(T, 113, 0.151500292036937400913870642638520668e-16),
  869. BOOST_MATH_BIG_CONSTANT(T, 113, 0.543475775154780935815530649335936121e-19),
  870. BOOST_MATH_BIG_CONSTANT(T, 113, 0.241647013434111434636554455083309352e-28),
  871. BOOST_MATH_BIG_CONSTANT(T, 113, -0.557103423021951053707162364713587374e-31),
  872. BOOST_MATH_BIG_CONSTANT(T, 113, 0.618708773442584843384712258199645166e-34),
  873. };
  874. // LCOV_EXCL_STOP
  875. result = tools::evaluate_polynomial(P, T(s - 30)) / tools::evaluate_polynomial(Q, T(s - 30));
  876. result = 1 + exp(result);
  877. }
  878. else
  879. {
  880. result = 1 + pow(T(2), -s);
  881. }
  882. return result;
  883. }
  884. template <class T, class Policy>
  885. T zeta_imp_odd_integer(int s, const T&, const Policy&, const std::true_type&)
  886. {
  887. // LCOV_EXCL_START
  888. static const T results[] = {
  889. BOOST_MATH_BIG_CONSTANT(T, 113, 1.2020569031595942853997381615114500), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0369277551433699263313654864570342), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0083492773819228268397975498497968), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0020083928260822144178527692324121), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0004941886041194645587022825264699), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0001227133475784891467518365263574), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000305882363070204935517285106451), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000076371976378997622736002935630), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000019082127165539389256569577951), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000004769329867878064631167196044), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000001192199259653110730677887189), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000298035035146522801860637051), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000074507117898354294919810042), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000018626597235130490064039099), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000004656629065033784072989233), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000001164155017270051977592974), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000291038504449709968692943), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000072759598350574810145209), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000018189896503070659475848), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000004547473783042154026799), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000001136868407680227849349), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000284217097688930185546), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000071054273952108527129), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000017763568435791203275), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000004440892103143813364), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000001110223025141066134), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000277555756213612417), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000069388939045441537), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000017347234760475766), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000004336808690020650), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000001084202172494241), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000000271050543122347), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000000067762635780452), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000000016940658945098), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000000004235164736273), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000000001058791184068), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000000000264697796017), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000000000066174449004), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000000000016543612251), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000000000004135903063), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000000000001033975766), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000000000000258493941), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000000000000064623485), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000000000000016155871), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000000000000004038968), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000000000000001009742), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000000000000000252435), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000000000000000063109), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000000000000000015777), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000000000000000003944), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000000000000000000986), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000000000000000000247), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000000000000000000062), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000000000000000000015), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000000000000000000004), BOOST_MATH_BIG_CONSTANT(T, 113, 1.0000000000000000000000000000000001),
  890. };
  891. // LCOV_EXCL_STOP
  892. return s > 113 ? 1 : results[(s - 3) / 2];
  893. }
  894. template <class T, class Policy>
  895. T zeta_imp_odd_integer(int s, const T& sc, const Policy& pol, const std::false_type&)
  896. {
  897. #ifdef BOOST_MATH_NO_THREAD_LOCAL_WITH_NON_TRIVIAL_TYPES
  898. static_assert(std::is_trivially_destructible<T>::value, "Your platform does not support thread_local with non-trivial types, last checked with Mingw-x64-8.1, Jan 2021. Please try a Mingw build with the POSIX threading model, see https://sourceforge.net/p/mingw-w64/bugs/527/");
  899. #endif
  900. // LCOV_EXCL_START
  901. static BOOST_MATH_THREAD_LOCAL bool is_init = false;
  902. static BOOST_MATH_THREAD_LOCAL T results[50] = {};
  903. static BOOST_MATH_THREAD_LOCAL int digits = tools::digits<T>();
  904. // LCOV_EXCL_STOP
  905. int current_digits = tools::digits<T>(); // LCOV_EXCL_LINE spurious miss as surrounding lines hit.
  906. if(digits != current_digits)
  907. {
  908. // Oh my precision has changed...
  909. is_init = false; // LCOV_EXCL_LINE variable precision MP case only, not included in coverage tests.
  910. }
  911. if(!is_init)
  912. {
  913. is_init = true;
  914. digits = current_digits;
  915. for(unsigned k = 0; k < sizeof(results) / sizeof(results[0]); ++k)
  916. {
  917. T arg = k * 2 + 3;
  918. T c_arg = 1 - arg; // LCOV_EXCL_LINE spurious miss as surrounding lines hit.
  919. results[k] = zeta_polynomial_series(arg, c_arg, pol);
  920. }
  921. }
  922. const unsigned index = static_cast<unsigned>((s - 3) / 2);
  923. return index >= sizeof(results) / sizeof(results[0]) ? zeta_polynomial_series(T(s), sc, pol): results[index];
  924. }
  925. template <class T, class Policy, class Tag>
  926. T zeta_imp(T s, T sc, const Policy& pol, const Tag& tag)
  927. {
  928. BOOST_MATH_STD_USING
  929. static const char* function = "boost::math::zeta<%1%>";
  930. if(sc == 0)
  931. return policies::raise_pole_error<T>(function, "Evaluation of zeta function at pole %1%", s, pol);
  932. T result; // LCOV_EXCL_LINE
  933. //
  934. // Trivial case:
  935. //
  936. if(s > policies::digits<T, Policy>())
  937. return 1;
  938. //
  939. // Start by seeing if we have a simple closed form:
  940. //
  941. if(floor(s) == s)
  942. {
  943. #ifndef BOOST_MATH_NO_EXCEPTIONS
  944. // Without exceptions we expect itrunc to return INT_MAX on overflow
  945. // and we fall through anyway.
  946. try
  947. {
  948. #endif
  949. int v = itrunc(s);
  950. if(v == s)
  951. {
  952. if(v < 0)
  953. {
  954. if(((-v) & 1) == 0)
  955. return 0;
  956. int n = (-v + 1) / 2;
  957. if(n <= (int)boost::math::max_bernoulli_b2n<T>::value)
  958. return T((-v & 1) ? -1 : 1) * boost::math::unchecked_bernoulli_b2n<T>(n) / (1 - v);
  959. }
  960. else if((v & 1) == 0)
  961. {
  962. if(((v / 2) <= (int)boost::math::max_bernoulli_b2n<T>::value) && (v <= (int)boost::math::max_factorial<T>::value))
  963. return T(((v / 2 - 1) & 1) ? -1 : 1) * ldexp(T(1), v - 1) * static_cast<T>(pow(constants::pi<T, Policy>(), T(v))) *
  964. boost::math::unchecked_bernoulli_b2n<T>(v / 2) / boost::math::unchecked_factorial<T>(v);
  965. return T(((v / 2 - 1) & 1) ? -1 : 1) * ldexp(T(1), v - 1) * static_cast<T>(pow(constants::pi<T, Policy>(), T(v))) *
  966. boost::math::bernoulli_b2n<T>(v / 2) / boost::math::factorial<T>(v, pol);
  967. }
  968. else
  969. return zeta_imp_odd_integer(v, sc, pol, std::integral_constant<bool, (Tag::value <= 113) && Tag::value>());
  970. }
  971. #ifndef BOOST_MATH_NO_EXCEPTIONS
  972. }
  973. catch(const boost::math::rounding_error&){} // Just fall through, s is too large to round
  974. catch(const std::overflow_error&){} // LCOV_EXCL_LINE We can only get here for "strange" MP types with small exponents and very large digit counts.
  975. #endif
  976. }
  977. if(fabs(s) < tools::root_epsilon<T>())
  978. {
  979. result = -0.5f - constants::log_root_two_pi<T, Policy>() * s;
  980. }
  981. else if(s < 0)
  982. {
  983. std::swap(s, sc);
  984. if(floor(sc/2) == sc/2)
  985. result = 0;
  986. else
  987. {
  988. if(s > max_factorial<T>::value)
  989. {
  990. T mult = boost::math::sin_pi(0.5f * sc, pol) * 2 * zeta_imp(s, sc, pol, tag);
  991. result = boost::math::lgamma(s, pol);
  992. result -= s * log(2 * constants::pi<T>());
  993. if(result > tools::log_max_value<T>())
  994. return sign(mult) * policies::raise_overflow_error<T>(function, nullptr, pol);
  995. result = exp(result);
  996. //
  997. // Whether this if branch can be triggered is very type dependent, we need
  998. // result to be just on the verge of overflow when /s/ is very close to a
  999. // half integer.
  1000. //
  1001. if(tools::max_value<T>() / fabs(mult) < result)
  1002. return boost::math::sign(mult) * policies::raise_overflow_error<T>(function, nullptr, pol); // LCOV_EXCL_LINE
  1003. result *= mult;
  1004. }
  1005. else
  1006. {
  1007. result = boost::math::sin_pi(0.5f * sc, pol)
  1008. * 2 * pow(2 * constants::pi<T>(), -s)
  1009. * boost::math::tgamma(s, pol)
  1010. * zeta_imp(s, sc, pol, tag);
  1011. }
  1012. }
  1013. }
  1014. else
  1015. {
  1016. result = zeta_imp_prec(s, sc, pol, tag);
  1017. }
  1018. return result;
  1019. }
  1020. } // detail
  1021. template <class T, class Policy>
  1022. inline typename tools::promote_args<T>::type zeta(T s, const Policy&)
  1023. {
  1024. typedef typename tools::promote_args<T>::type result_type;
  1025. typedef typename policies::evaluation<result_type, Policy>::type value_type;
  1026. typedef typename policies::precision<result_type, Policy>::type precision_type;
  1027. typedef typename policies::normalise<
  1028. Policy,
  1029. policies::promote_float<false>,
  1030. policies::promote_double<false>,
  1031. policies::discrete_quantile<>,
  1032. policies::assert_undefined<> >::type forwarding_policy;
  1033. typedef std::integral_constant<int,
  1034. precision_type::value <= 0 ? 0 :
  1035. precision_type::value <= 53 ? 53 :
  1036. precision_type::value <= 64 ? 64 :
  1037. precision_type::value <= 113 ? 113 : 0
  1038. > tag_type;
  1039. return policies::checked_narrowing_cast<result_type, forwarding_policy>(detail::zeta_imp(
  1040. static_cast<value_type>(s),
  1041. static_cast<value_type>(1 - static_cast<value_type>(s)),
  1042. forwarding_policy(),
  1043. tag_type()), "boost::math::zeta<%1%>(%1%)");
  1044. }
  1045. template <class T>
  1046. inline typename tools::promote_args<T>::type zeta(T s)
  1047. {
  1048. return zeta(s, policies::policy<>());
  1049. }
  1050. }} // namespaces
  1051. #endif // BOOST_MATH_ZETA_HPP