zeta.hpp 43 KB

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  1. // Copyright John Maddock 2007.
  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/tools/precision.hpp>
  11. #include <boost/math/tools/series.hpp>
  12. #include <boost/math/tools/big_constant.hpp>
  13. #include <boost/math/policies/error_handling.hpp>
  14. #include <boost/math/special_functions/gamma.hpp>
  15. #include <boost/math/special_functions/sin_pi.hpp>
  16. namespace boost{ namespace math{ namespace detail{
  17. #if 0
  18. //
  19. // This code is commented out because we have a better more rapidly converging series
  20. // now. Retained for future reference and in case the new code causes any issues down the line....
  21. //
  22. template <class T, class Policy>
  23. struct zeta_series_cache_size
  24. {
  25. //
  26. // Work how large to make our cache size when evaluating the series
  27. // evaluation: normally this is just large enough for the series
  28. // to have converged, but for arbitrary precision types we need a
  29. // really large cache to achieve reasonable precision in a reasonable
  30. // time. This is important when constructing rational approximations
  31. // to zeta for example.
  32. //
  33. typedef typename boost::math::policies::precision<T,Policy>::type precision_type;
  34. typedef typename mpl::if_<
  35. mpl::less_equal<precision_type, mpl::int_<0> >,
  36. mpl::int_<5000>,
  37. typename mpl::if_<
  38. mpl::less_equal<precision_type, mpl::int_<64> >,
  39. mpl::int_<70>,
  40. typename mpl::if_<
  41. mpl::less_equal<precision_type, mpl::int_<113> >,
  42. mpl::int_<100>,
  43. mpl::int_<5000>
  44. >::type
  45. >::type
  46. >::type type;
  47. };
  48. template <class T, class Policy>
  49. T zeta_series_imp(T s, T sc, const Policy&)
  50. {
  51. //
  52. // Series evaluation from:
  53. // Havil, J. Gamma: Exploring Euler's Constant.
  54. // Princeton, NJ: Princeton University Press, 2003.
  55. //
  56. // See also http://mathworld.wolfram.com/RiemannZetaFunction.html
  57. //
  58. BOOST_MATH_STD_USING
  59. T sum = 0;
  60. T mult = 0.5;
  61. T change;
  62. typedef typename zeta_series_cache_size<T,Policy>::type cache_size;
  63. T powers[cache_size::value] = { 0, };
  64. unsigned n = 0;
  65. do{
  66. T binom = -static_cast<T>(n);
  67. T nested_sum = 1;
  68. if(n < sizeof(powers) / sizeof(powers[0]))
  69. powers[n] = pow(static_cast<T>(n + 1), -s);
  70. for(unsigned k = 1; k <= n; ++k)
  71. {
  72. T p;
  73. if(k < sizeof(powers) / sizeof(powers[0]))
  74. {
  75. p = powers[k];
  76. //p = pow(k + 1, -s);
  77. }
  78. else
  79. p = pow(static_cast<T>(k + 1), -s);
  80. nested_sum += binom * p;
  81. binom *= (k - static_cast<T>(n)) / (k + 1);
  82. }
  83. change = mult * nested_sum;
  84. sum += change;
  85. mult /= 2;
  86. ++n;
  87. }while(fabs(change / sum) > tools::epsilon<T>());
  88. return sum * 1 / -boost::math::powm1(T(2), sc);
  89. }
  90. //
  91. // Classical p-series:
  92. //
  93. template <class T>
  94. struct zeta_series2
  95. {
  96. typedef T result_type;
  97. zeta_series2(T _s) : s(-_s), k(1){}
  98. T operator()()
  99. {
  100. BOOST_MATH_STD_USING
  101. return pow(static_cast<T>(k++), s);
  102. }
  103. private:
  104. T s;
  105. unsigned k;
  106. };
  107. template <class T, class Policy>
  108. inline T zeta_series2_imp(T s, const Policy& pol)
  109. {
  110. boost::uintmax_t max_iter = policies::get_max_series_iterations<Policy>();;
  111. zeta_series2<T> f(s);
  112. T result = tools::sum_series(
  113. f,
  114. policies::get_epsilon<T, Policy>(),
  115. max_iter);
  116. policies::check_series_iterations<T>("boost::math::zeta_series2<%1%>(%1%)", max_iter, pol);
  117. return result;
  118. }
  119. #endif
  120. template <class T, class Policy>
  121. T zeta_polynomial_series(T s, T sc, Policy const &)
  122. {
  123. //
  124. // This is algorithm 3 from:
  125. //
  126. // "An Efficient Algorithm for the Riemann Zeta Function", P. Borwein,
  127. // Canadian Mathematical Society, Conference Proceedings.
  128. // See: http://www.cecm.sfu.ca/personal/pborwein/PAPERS/P155.pdf
  129. //
  130. BOOST_MATH_STD_USING
  131. int n = itrunc(T(log(boost::math::tools::epsilon<T>()) / -2));
  132. T sum = 0;
  133. T two_n = ldexp(T(1), n);
  134. int ej_sign = 1;
  135. for(int j = 0; j < n; ++j)
  136. {
  137. sum += ej_sign * -two_n / pow(T(j + 1), s);
  138. ej_sign = -ej_sign;
  139. }
  140. T ej_sum = 1;
  141. T ej_term = 1;
  142. for(int j = n; j <= 2 * n - 1; ++j)
  143. {
  144. sum += ej_sign * (ej_sum - two_n) / pow(T(j + 1), s);
  145. ej_sign = -ej_sign;
  146. ej_term *= 2 * n - j;
  147. ej_term /= j - n + 1;
  148. ej_sum += ej_term;
  149. }
  150. return -sum / (two_n * (-powm1(T(2), sc)));
  151. }
  152. template <class T, class Policy>
  153. T zeta_imp_prec(T s, T sc, const Policy& pol, const mpl::int_<0>&)
  154. {
  155. BOOST_MATH_STD_USING
  156. T result;
  157. result = zeta_polynomial_series(s, sc, pol);
  158. #if 0
  159. // Old code archived for future reference:
  160. //
  161. // Only use power series if it will converge in 100
  162. // iterations or less: the more iterations it consumes
  163. // the slower convergence becomes so we have to be very
  164. // careful in it's usage.
  165. //
  166. if (s > -log(tools::epsilon<T>()) / 4.5)
  167. result = detail::zeta_series2_imp(s, pol);
  168. else
  169. result = detail::zeta_series_imp(s, sc, pol);
  170. #endif
  171. return result;
  172. }
  173. template <class T, class Policy>
  174. inline T zeta_imp_prec(T s, T sc, const Policy&, const mpl::int_<53>&)
  175. {
  176. BOOST_MATH_STD_USING
  177. T result;
  178. if(s < 1)
  179. {
  180. // Rational Approximation
  181. // Maximum Deviation Found: 2.020e-18
  182. // Expected Error Term: -2.020e-18
  183. // Max error found at double precision: 3.994987e-17
  184. static const T P[6] = {
  185. 0.24339294433593750202L,
  186. -0.49092470516353571651L,
  187. 0.0557616214776046784287L,
  188. -0.00320912498879085894856L,
  189. 0.000451534528645796438704L,
  190. -0.933241270357061460782e-5L,
  191. };
  192. static const T Q[6] = {
  193. 1L,
  194. -0.279960334310344432495L,
  195. 0.0419676223309986037706L,
  196. -0.00413421406552171059003L,
  197. 0.00024978985622317935355L,
  198. -0.101855788418564031874e-4L,
  199. };
  200. result = tools::evaluate_polynomial(P, sc) / tools::evaluate_polynomial(Q, sc);
  201. result -= 1.2433929443359375F;
  202. result += (sc);
  203. result /= (sc);
  204. }
  205. else if(s <= 2)
  206. {
  207. // Maximum Deviation Found: 9.007e-20
  208. // Expected Error Term: 9.007e-20
  209. static const T P[6] = {
  210. 0.577215664901532860516,
  211. 0.243210646940107164097,
  212. 0.0417364673988216497593,
  213. 0.00390252087072843288378,
  214. 0.000249606367151877175456,
  215. 0.110108440976732897969e-4,
  216. };
  217. static const T Q[6] = {
  218. 1,
  219. 0.295201277126631761737,
  220. 0.043460910607305495864,
  221. 0.00434930582085826330659,
  222. 0.000255784226140488490982,
  223. 0.10991819782396112081e-4,
  224. };
  225. result = tools::evaluate_polynomial(P, T(-sc)) / tools::evaluate_polynomial(Q, T(-sc));
  226. result += 1 / (-sc);
  227. }
  228. else if(s <= 4)
  229. {
  230. // Maximum Deviation Found: 5.946e-22
  231. // Expected Error Term: -5.946e-22
  232. static const float Y = 0.6986598968505859375;
  233. static const T P[6] = {
  234. -0.0537258300023595030676,
  235. 0.0445163473292365591906,
  236. 0.0128677673534519952905,
  237. 0.00097541770457391752726,
  238. 0.769875101573654070925e-4,
  239. 0.328032510000383084155e-5,
  240. };
  241. static const T Q[7] = {
  242. 1,
  243. 0.33383194553034051422,
  244. 0.0487798431291407621462,
  245. 0.00479039708573558490716,
  246. 0.000270776703956336357707,
  247. 0.106951867532057341359e-4,
  248. 0.236276623974978646399e-7,
  249. };
  250. result = tools::evaluate_polynomial(P, T(s - 2)) / tools::evaluate_polynomial(Q, T(s - 2));
  251. result += Y + 1 / (-sc);
  252. }
  253. else if(s <= 7)
  254. {
  255. // Maximum Deviation Found: 2.955e-17
  256. // Expected Error Term: 2.955e-17
  257. // Max error found at double precision: 2.009135e-16
  258. static const T P[6] = {
  259. -2.49710190602259410021,
  260. -2.60013301809475665334,
  261. -0.939260435377109939261,
  262. -0.138448617995741530935,
  263. -0.00701721240549802377623,
  264. -0.229257310594893932383e-4,
  265. };
  266. static const T Q[9] = {
  267. 1,
  268. 0.706039025937745133628,
  269. 0.15739599649558626358,
  270. 0.0106117950976845084417,
  271. -0.36910273311764618902e-4,
  272. 0.493409563927590008943e-5,
  273. -0.234055487025287216506e-6,
  274. 0.718833729365459760664e-8,
  275. -0.1129200113474947419e-9,
  276. };
  277. result = tools::evaluate_polynomial(P, T(s - 4)) / tools::evaluate_polynomial(Q, T(s - 4));
  278. result = 1 + exp(result);
  279. }
  280. else if(s < 15)
  281. {
  282. // Maximum Deviation Found: 7.117e-16
  283. // Expected Error Term: 7.117e-16
  284. // Max error found at double precision: 9.387771e-16
  285. static const T P[7] = {
  286. -4.78558028495135619286,
  287. -1.89197364881972536382,
  288. -0.211407134874412820099,
  289. -0.000189204758260076688518,
  290. 0.00115140923889178742086,
  291. 0.639949204213164496988e-4,
  292. 0.139348932445324888343e-5,
  293. };
  294. static const T Q[9] = {
  295. 1,
  296. 0.244345337378188557777,
  297. 0.00873370754492288653669,
  298. -0.00117592765334434471562,
  299. -0.743743682899933180415e-4,
  300. -0.21750464515767984778e-5,
  301. 0.471001264003076486547e-8,
  302. -0.833378440625385520576e-10,
  303. 0.699841545204845636531e-12,
  304. };
  305. result = tools::evaluate_polynomial(P, T(s - 7)) / tools::evaluate_polynomial(Q, T(s - 7));
  306. result = 1 + exp(result);
  307. }
  308. else if(s < 36)
  309. {
  310. // Max error in interpolated form: 1.668e-17
  311. // Max error found at long double precision: 1.669714e-17
  312. static const T P[8] = {
  313. -10.3948950573308896825,
  314. -2.85827219671106697179,
  315. -0.347728266539245787271,
  316. -0.0251156064655346341766,
  317. -0.00119459173416968685689,
  318. -0.382529323507967522614e-4,
  319. -0.785523633796723466968e-6,
  320. -0.821465709095465524192e-8,
  321. };
  322. static const T Q[10] = {
  323. 1,
  324. 0.208196333572671890965,
  325. 0.0195687657317205033485,
  326. 0.00111079638102485921877,
  327. 0.408507746266039256231e-4,
  328. 0.955561123065693483991e-6,
  329. 0.118507153474022900583e-7,
  330. 0.222609483627352615142e-14,
  331. };
  332. result = tools::evaluate_polynomial(P, T(s - 15)) / tools::evaluate_polynomial(Q, T(s - 15));
  333. result = 1 + exp(result);
  334. }
  335. else if(s < 56)
  336. {
  337. result = 1 + pow(T(2), -s);
  338. }
  339. else
  340. {
  341. result = 1;
  342. }
  343. return result;
  344. }
  345. template <class T, class Policy>
  346. T zeta_imp_prec(T s, T sc, const Policy&, const mpl::int_<64>&)
  347. {
  348. BOOST_MATH_STD_USING
  349. T result;
  350. if(s < 1)
  351. {
  352. // Rational Approximation
  353. // Maximum Deviation Found: 3.099e-20
  354. // Expected Error Term: 3.099e-20
  355. // Max error found at long double precision: 5.890498e-20
  356. static const T P[6] = {
  357. BOOST_MATH_BIG_CONSTANT(T, 64, 0.243392944335937499969),
  358. BOOST_MATH_BIG_CONSTANT(T, 64, -0.496837806864865688082),
  359. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0680008039723709987107),
  360. BOOST_MATH_BIG_CONSTANT(T, 64, -0.00511620413006619942112),
  361. BOOST_MATH_BIG_CONSTANT(T, 64, 0.000455369899250053003335),
  362. BOOST_MATH_BIG_CONSTANT(T, 64, -0.279496685273033761927e-4),
  363. };
  364. static const T Q[7] = {
  365. BOOST_MATH_BIG_CONSTANT(T, 64, 1),
  366. BOOST_MATH_BIG_CONSTANT(T, 64, -0.30425480068225790522),
  367. BOOST_MATH_BIG_CONSTANT(T, 64, 0.050052748580371598736),
  368. BOOST_MATH_BIG_CONSTANT(T, 64, -0.00519355671064700627862),
  369. BOOST_MATH_BIG_CONSTANT(T, 64, 0.000360623385771198350257),
  370. BOOST_MATH_BIG_CONSTANT(T, 64, -0.159600883054550987633e-4),
  371. BOOST_MATH_BIG_CONSTANT(T, 64, 0.339770279812410586032e-6),
  372. };
  373. result = tools::evaluate_polynomial(P, sc) / tools::evaluate_polynomial(Q, sc);
  374. result -= 1.2433929443359375F;
  375. result += (sc);
  376. result /= (sc);
  377. }
  378. else if(s <= 2)
  379. {
  380. // Maximum Deviation Found: 1.059e-21
  381. // Expected Error Term: 1.059e-21
  382. // Max error found at long double precision: 1.626303e-19
  383. static const T P[6] = {
  384. BOOST_MATH_BIG_CONSTANT(T, 64, 0.577215664901532860605),
  385. BOOST_MATH_BIG_CONSTANT(T, 64, 0.222537368917162139445),
  386. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0356286324033215682729),
  387. BOOST_MATH_BIG_CONSTANT(T, 64, 0.00304465292366350081446),
  388. BOOST_MATH_BIG_CONSTANT(T, 64, 0.000178102511649069421904),
  389. BOOST_MATH_BIG_CONSTANT(T, 64, 0.700867470265983665042e-5),
  390. };
  391. static const T Q[7] = {
  392. BOOST_MATH_BIG_CONSTANT(T, 64, 1),
  393. BOOST_MATH_BIG_CONSTANT(T, 64, 0.259385759149531030085),
  394. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0373974962106091316854),
  395. BOOST_MATH_BIG_CONSTANT(T, 64, 0.00332735159183332820617),
  396. BOOST_MATH_BIG_CONSTANT(T, 64, 0.000188690420706998606469),
  397. BOOST_MATH_BIG_CONSTANT(T, 64, 0.635994377921861930071e-5),
  398. BOOST_MATH_BIG_CONSTANT(T, 64, 0.226583954978371199405e-7),
  399. };
  400. result = tools::evaluate_polynomial(P, T(-sc)) / tools::evaluate_polynomial(Q, T(-sc));
  401. result += 1 / (-sc);
  402. }
  403. else if(s <= 4)
  404. {
  405. // Maximum Deviation Found: 5.946e-22
  406. // Expected Error Term: -5.946e-22
  407. static const float Y = 0.6986598968505859375;
  408. static const T P[7] = {
  409. BOOST_MATH_BIG_CONSTANT(T, 64, -0.053725830002359501027),
  410. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0470551187571475844778),
  411. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0101339410415759517471),
  412. BOOST_MATH_BIG_CONSTANT(T, 64, 0.00100240326666092854528),
  413. BOOST_MATH_BIG_CONSTANT(T, 64, 0.685027119098122814867e-4),
  414. BOOST_MATH_BIG_CONSTANT(T, 64, 0.390972820219765942117e-5),
  415. BOOST_MATH_BIG_CONSTANT(T, 64, 0.540319769113543934483e-7),
  416. };
  417. static const T Q[8] = {
  418. BOOST_MATH_BIG_CONSTANT(T, 64, 1.0),
  419. BOOST_MATH_BIG_CONSTANT(T, 64, 0.286577739726542730421),
  420. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0447355811517733225843),
  421. BOOST_MATH_BIG_CONSTANT(T, 64, 0.00430125107610252363302),
  422. BOOST_MATH_BIG_CONSTANT(T, 64, 0.000284956969089786662045),
  423. BOOST_MATH_BIG_CONSTANT(T, 64, 0.116188101609848411329e-4),
  424. BOOST_MATH_BIG_CONSTANT(T, 64, 0.278090318191657278204e-6),
  425. BOOST_MATH_BIG_CONSTANT(T, 64, -0.19683620233222028478e-8),
  426. };
  427. result = tools::evaluate_polynomial(P, T(s - 2)) / tools::evaluate_polynomial(Q, T(s - 2));
  428. result += Y + 1 / (-sc);
  429. }
  430. else if(s <= 7)
  431. {
  432. // Max error found at long double precision: 8.132216e-19
  433. static const T P[8] = {
  434. BOOST_MATH_BIG_CONSTANT(T, 64, -2.49710190602259407065),
  435. BOOST_MATH_BIG_CONSTANT(T, 64, -3.36664913245960625334),
  436. BOOST_MATH_BIG_CONSTANT(T, 64, -1.77180020623777595452),
  437. BOOST_MATH_BIG_CONSTANT(T, 64, -0.464717885249654313933),
  438. BOOST_MATH_BIG_CONSTANT(T, 64, -0.0643694921293579472583),
  439. BOOST_MATH_BIG_CONSTANT(T, 64, -0.00464265386202805715487),
  440. BOOST_MATH_BIG_CONSTANT(T, 64, -0.000165556579779704340166),
  441. BOOST_MATH_BIG_CONSTANT(T, 64, -0.252884970740994069582e-5),
  442. };
  443. static const T Q[9] = {
  444. BOOST_MATH_BIG_CONSTANT(T, 64, 1.0),
  445. BOOST_MATH_BIG_CONSTANT(T, 64, 1.01300131390690459085),
  446. BOOST_MATH_BIG_CONSTANT(T, 64, 0.387898115758643503827),
  447. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0695071490045701135188),
  448. BOOST_MATH_BIG_CONSTANT(T, 64, 0.00586908595251442839291),
  449. BOOST_MATH_BIG_CONSTANT(T, 64, 0.000217752974064612188616),
  450. BOOST_MATH_BIG_CONSTANT(T, 64, 0.397626583349419011731e-5),
  451. BOOST_MATH_BIG_CONSTANT(T, 64, -0.927884739284359700764e-8),
  452. BOOST_MATH_BIG_CONSTANT(T, 64, 0.119810501805618894381e-9),
  453. };
  454. result = tools::evaluate_polynomial(P, T(s - 4)) / tools::evaluate_polynomial(Q, T(s - 4));
  455. result = 1 + exp(result);
  456. }
  457. else if(s < 15)
  458. {
  459. // Max error in interpolated form: 1.133e-18
  460. // Max error found at long double precision: 2.183198e-18
  461. static const T P[9] = {
  462. BOOST_MATH_BIG_CONSTANT(T, 64, -4.78558028495135548083),
  463. BOOST_MATH_BIG_CONSTANT(T, 64, -3.23873322238609358947),
  464. BOOST_MATH_BIG_CONSTANT(T, 64, -0.892338582881021799922),
  465. BOOST_MATH_BIG_CONSTANT(T, 64, -0.131326296217965913809),
  466. BOOST_MATH_BIG_CONSTANT(T, 64, -0.0115651591773783712996),
  467. BOOST_MATH_BIG_CONSTANT(T, 64, -0.000657728968362695775205),
  468. BOOST_MATH_BIG_CONSTANT(T, 64, -0.252051328129449973047e-4),
  469. BOOST_MATH_BIG_CONSTANT(T, 64, -0.626503445372641798925e-6),
  470. BOOST_MATH_BIG_CONSTANT(T, 64, -0.815696314790853893484e-8),
  471. };
  472. static const T Q[9] = {
  473. BOOST_MATH_BIG_CONSTANT(T, 64, 1.0),
  474. BOOST_MATH_BIG_CONSTANT(T, 64, 0.525765665400123515036),
  475. BOOST_MATH_BIG_CONSTANT(T, 64, 0.10852641753657122787),
  476. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0115669945375362045249),
  477. BOOST_MATH_BIG_CONSTANT(T, 64, 0.000732896513858274091966),
  478. BOOST_MATH_BIG_CONSTANT(T, 64, 0.30683952282420248448e-4),
  479. BOOST_MATH_BIG_CONSTANT(T, 64, 0.819649214609633126119e-6),
  480. BOOST_MATH_BIG_CONSTANT(T, 64, 0.117957556472335968146e-7),
  481. BOOST_MATH_BIG_CONSTANT(T, 64, -0.193432300973017671137e-12),
  482. };
  483. result = tools::evaluate_polynomial(P, T(s - 7)) / tools::evaluate_polynomial(Q, T(s - 7));
  484. result = 1 + exp(result);
  485. }
  486. else if(s < 42)
  487. {
  488. // Max error in interpolated form: 1.668e-17
  489. // Max error found at long double precision: 1.669714e-17
  490. static const T P[9] = {
  491. BOOST_MATH_BIG_CONSTANT(T, 64, -10.3948950573308861781),
  492. BOOST_MATH_BIG_CONSTANT(T, 64, -2.82646012777913950108),
  493. BOOST_MATH_BIG_CONSTANT(T, 64, -0.342144362739570333665),
  494. BOOST_MATH_BIG_CONSTANT(T, 64, -0.0249285145498722647472),
  495. BOOST_MATH_BIG_CONSTANT(T, 64, -0.00122493108848097114118),
  496. BOOST_MATH_BIG_CONSTANT(T, 64, -0.423055371192592850196e-4),
  497. BOOST_MATH_BIG_CONSTANT(T, 64, -0.1025215577185967488e-5),
  498. BOOST_MATH_BIG_CONSTANT(T, 64, -0.165096762663509467061e-7),
  499. BOOST_MATH_BIG_CONSTANT(T, 64, -0.145392555873022044329e-9),
  500. };
  501. static const T Q[10] = {
  502. BOOST_MATH_BIG_CONSTANT(T, 64, 1.0),
  503. BOOST_MATH_BIG_CONSTANT(T, 64, 0.205135978585281988052),
  504. BOOST_MATH_BIG_CONSTANT(T, 64, 0.0192359357875879453602),
  505. BOOST_MATH_BIG_CONSTANT(T, 64, 0.00111496452029715514119),
  506. BOOST_MATH_BIG_CONSTANT(T, 64, 0.434928449016693986857e-4),
  507. BOOST_MATH_BIG_CONSTANT(T, 64, 0.116911068726610725891e-5),
  508. BOOST_MATH_BIG_CONSTANT(T, 64, 0.206704342290235237475e-7),
  509. BOOST_MATH_BIG_CONSTANT(T, 64, 0.209772836100827647474e-9),
  510. BOOST_MATH_BIG_CONSTANT(T, 64, -0.939798249922234703384e-16),
  511. BOOST_MATH_BIG_CONSTANT(T, 64, 0.264584017421245080294e-18),
  512. };
  513. result = tools::evaluate_polynomial(P, T(s - 15)) / tools::evaluate_polynomial(Q, T(s - 15));
  514. result = 1 + exp(result);
  515. }
  516. else if(s < 63)
  517. {
  518. result = 1 + pow(T(2), -s);
  519. }
  520. else
  521. {
  522. result = 1;
  523. }
  524. return result;
  525. }
  526. template <class T, class Policy>
  527. T zeta_imp_prec(T s, T sc, const Policy&, const mpl::int_<113>&)
  528. {
  529. BOOST_MATH_STD_USING
  530. T result;
  531. if(s < 1)
  532. {
  533. // Rational Approximation
  534. // Maximum Deviation Found: 9.493e-37
  535. // Expected Error Term: 9.492e-37
  536. // Max error found at long double precision: 7.281332e-31
  537. static const T P[10] = {
  538. BOOST_MATH_BIG_CONSTANT(T, 113, -1),
  539. BOOST_MATH_BIG_CONSTANT(T, 113, -0.0353008629988648122808504280990313668),
  540. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0107795651204927743049369868548706909),
  541. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000523961870530500751114866884685172975),
  542. BOOST_MATH_BIG_CONSTANT(T, 113, -0.661805838304910731947595897966487515e-4),
  543. BOOST_MATH_BIG_CONSTANT(T, 113, -0.658932670403818558510656304189164638e-5),
  544. BOOST_MATH_BIG_CONSTANT(T, 113, -0.103437265642266106533814021041010453e-6),
  545. BOOST_MATH_BIG_CONSTANT(T, 113, 0.116818787212666457105375746642927737e-7),
  546. BOOST_MATH_BIG_CONSTANT(T, 113, 0.660690993901506912123512551294239036e-9),
  547. BOOST_MATH_BIG_CONSTANT(T, 113, 0.113103113698388531428914333768142527e-10),
  548. };
  549. static const T Q[11] = {
  550. BOOST_MATH_BIG_CONSTANT(T, 113, 1),
  551. BOOST_MATH_BIG_CONSTANT(T, 113, -0.387483472099602327112637481818565459),
  552. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0802265315091063135271497708694776875),
  553. BOOST_MATH_BIG_CONSTANT(T, 113, -0.0110727276164171919280036408995078164),
  554. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00112552716946286252000434849173787243),
  555. BOOST_MATH_BIG_CONSTANT(T, 113, -0.874554160748626916455655180296834352e-4),
  556. BOOST_MATH_BIG_CONSTANT(T, 113, 0.530097847491828379568636739662278322e-5),
  557. BOOST_MATH_BIG_CONSTANT(T, 113, -0.248461553590496154705565904497247452e-6),
  558. BOOST_MATH_BIG_CONSTANT(T, 113, 0.881834921354014787309644951507523899e-8),
  559. BOOST_MATH_BIG_CONSTANT(T, 113, -0.217062446168217797598596496310953025e-9),
  560. BOOST_MATH_BIG_CONSTANT(T, 113, 0.315823200002384492377987848307151168e-11),
  561. };
  562. result = tools::evaluate_polynomial(P, sc) / tools::evaluate_polynomial(Q, sc);
  563. result += (sc);
  564. result /= (sc);
  565. }
  566. else if(s <= 2)
  567. {
  568. // Maximum Deviation Found: 1.616e-37
  569. // Expected Error Term: -1.615e-37
  570. static const T P[10] = {
  571. BOOST_MATH_BIG_CONSTANT(T, 113, 0.577215664901532860606512090082402431),
  572. BOOST_MATH_BIG_CONSTANT(T, 113, 0.255597968739771510415479842335906308),
  573. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0494056503552807274142218876983542205),
  574. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00551372778611700965268920983472292325),
  575. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00043667616723970574871427830895192731),
  576. BOOST_MATH_BIG_CONSTANT(T, 113, 0.268562259154821957743669387915239528e-4),
  577. BOOST_MATH_BIG_CONSTANT(T, 113, 0.109249633923016310141743084480436612e-5),
  578. BOOST_MATH_BIG_CONSTANT(T, 113, 0.273895554345300227466534378753023924e-7),
  579. BOOST_MATH_BIG_CONSTANT(T, 113, 0.583103205551702720149237384027795038e-9),
  580. BOOST_MATH_BIG_CONSTANT(T, 113, -0.835774625259919268768735944711219256e-11),
  581. };
  582. static const T Q[11] = {
  583. BOOST_MATH_BIG_CONSTANT(T, 113, 1),
  584. BOOST_MATH_BIG_CONSTANT(T, 113, 0.316661751179735502065583176348292881),
  585. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0540401806533507064453851182728635272),
  586. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00598621274107420237785899476374043797),
  587. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000474907812321704156213038740142079615),
  588. BOOST_MATH_BIG_CONSTANT(T, 113, 0.272125421722314389581695715835862418e-4),
  589. BOOST_MATH_BIG_CONSTANT(T, 113, 0.112649552156479800925522445229212933e-5),
  590. BOOST_MATH_BIG_CONSTANT(T, 113, 0.301838975502992622733000078063330461e-7),
  591. BOOST_MATH_BIG_CONSTANT(T, 113, 0.422960728687211282539769943184270106e-9),
  592. BOOST_MATH_BIG_CONSTANT(T, 113, -0.377105263588822468076813329270698909e-11),
  593. BOOST_MATH_BIG_CONSTANT(T, 113, -0.581926559304525152432462127383600681e-13),
  594. };
  595. result = tools::evaluate_polynomial(P, T(-sc)) / tools::evaluate_polynomial(Q, T(-sc));
  596. result += 1 / (-sc);
  597. }
  598. else if(s <= 4)
  599. {
  600. // Maximum Deviation Found: 1.891e-36
  601. // Expected Error Term: -1.891e-36
  602. // Max error found: 2.171527e-35
  603. static const float Y = 0.6986598968505859375;
  604. static const T P[11] = {
  605. BOOST_MATH_BIG_CONSTANT(T, 113, -0.0537258300023595010275848333539748089),
  606. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0429086930802630159457448174466342553),
  607. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0136148228754303412510213395034056857),
  608. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00190231601036042925183751238033763915),
  609. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000186880390916311438818302549192456581),
  610. BOOST_MATH_BIG_CONSTANT(T, 113, 0.145347370745893262394287982691323657e-4),
  611. BOOST_MATH_BIG_CONSTANT(T, 113, 0.805843276446813106414036600485884885e-6),
  612. BOOST_MATH_BIG_CONSTANT(T, 113, 0.340818159286739137503297172091882574e-7),
  613. BOOST_MATH_BIG_CONSTANT(T, 113, 0.115762357488748996526167305116837246e-8),
  614. BOOST_MATH_BIG_CONSTANT(T, 113, 0.231904754577648077579913403645767214e-10),
  615. BOOST_MATH_BIG_CONSTANT(T, 113, 0.340169592866058506675897646629036044e-12),
  616. };
  617. static const T Q[12] = {
  618. BOOST_MATH_BIG_CONSTANT(T, 113, 1),
  619. BOOST_MATH_BIG_CONSTANT(T, 113, 0.363755247765087100018556983050520554),
  620. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0696581979014242539385695131258321598),
  621. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00882208914484611029571547753782014817),
  622. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000815405623261946661762236085660996718),
  623. BOOST_MATH_BIG_CONSTANT(T, 113, 0.571366167062457197282642344940445452e-4),
  624. BOOST_MATH_BIG_CONSTANT(T, 113, 0.309278269271853502353954062051797838e-5),
  625. BOOST_MATH_BIG_CONSTANT(T, 113, 0.12822982083479010834070516053794262e-6),
  626. BOOST_MATH_BIG_CONSTANT(T, 113, 0.397876357325018976733953479182110033e-8),
  627. BOOST_MATH_BIG_CONSTANT(T, 113, 0.8484432107648683277598472295289279e-10),
  628. BOOST_MATH_BIG_CONSTANT(T, 113, 0.105677416606909614301995218444080615e-11),
  629. BOOST_MATH_BIG_CONSTANT(T, 113, 0.547223964564003701979951154093005354e-15),
  630. };
  631. result = tools::evaluate_polynomial(P, T(s - 2)) / tools::evaluate_polynomial(Q, T(s - 2));
  632. result += Y + 1 / (-sc);
  633. }
  634. else if(s <= 6)
  635. {
  636. // Max error in interpolated form: 1.510e-37
  637. // Max error found at long double precision: 2.769266e-34
  638. static const T Y = 3.28348541259765625F;
  639. static const T P[13] = {
  640. BOOST_MATH_BIG_CONSTANT(T, 113, 0.786383506575062179339611614117697622),
  641. BOOST_MATH_BIG_CONSTANT(T, 113, 0.495766593395271370974685959652073976),
  642. BOOST_MATH_BIG_CONSTANT(T, 113, -0.409116737851754766422360889037532228),
  643. BOOST_MATH_BIG_CONSTANT(T, 113, -0.57340744006238263817895456842655987),
  644. BOOST_MATH_BIG_CONSTANT(T, 113, -0.280479899797421910694892949057963111),
  645. BOOST_MATH_BIG_CONSTANT(T, 113, -0.0753148409447590257157585696212649869),
  646. BOOST_MATH_BIG_CONSTANT(T, 113, -0.0122934003684672788499099362823748632),
  647. BOOST_MATH_BIG_CONSTANT(T, 113, -0.00126148398446193639247961370266962927),
  648. BOOST_MATH_BIG_CONSTANT(T, 113, -0.828465038179772939844657040917364896e-4),
  649. BOOST_MATH_BIG_CONSTANT(T, 113, -0.361008916706050977143208468690645684e-5),
  650. BOOST_MATH_BIG_CONSTANT(T, 113, -0.109879825497910544424797771195928112e-6),
  651. BOOST_MATH_BIG_CONSTANT(T, 113, -0.214539416789686920918063075528797059e-8),
  652. BOOST_MATH_BIG_CONSTANT(T, 113, -0.15090220092460596872172844424267351e-10),
  653. };
  654. static const T Q[14] = {
  655. BOOST_MATH_BIG_CONSTANT(T, 113, 1),
  656. BOOST_MATH_BIG_CONSTANT(T, 113, 1.69490865837142338462982225731926485),
  657. BOOST_MATH_BIG_CONSTANT(T, 113, 1.22697696630994080733321401255942464),
  658. BOOST_MATH_BIG_CONSTANT(T, 113, 0.495409420862526540074366618006341533),
  659. BOOST_MATH_BIG_CONSTANT(T, 113, 0.122368084916843823462872905024259633),
  660. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0191412993625268971656513890888208623),
  661. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00191401538628980617753082598351559642),
  662. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000123318142456272424148930280876444459),
  663. BOOST_MATH_BIG_CONSTANT(T, 113, 0.531945488232526067889835342277595709e-5),
  664. BOOST_MATH_BIG_CONSTANT(T, 113, 0.161843184071894368337068779669116236e-6),
  665. BOOST_MATH_BIG_CONSTANT(T, 113, 0.305796079600152506743828859577462778e-8),
  666. BOOST_MATH_BIG_CONSTANT(T, 113, 0.233582592298450202680170811044408894e-10),
  667. BOOST_MATH_BIG_CONSTANT(T, 113, -0.275363878344548055574209713637734269e-13),
  668. BOOST_MATH_BIG_CONSTANT(T, 113, 0.221564186807357535475441900517843892e-15),
  669. };
  670. result = tools::evaluate_polynomial(P, T(s - 4)) / tools::evaluate_polynomial(Q, T(s - 4));
  671. result -= Y;
  672. result = 1 + exp(result);
  673. }
  674. else if(s < 10)
  675. {
  676. // Max error in interpolated form: 1.999e-34
  677. // Max error found at long double precision: 2.156186e-33
  678. static const T P[13] = {
  679. BOOST_MATH_BIG_CONSTANT(T, 113, -4.0545627381873738086704293881227365),
  680. BOOST_MATH_BIG_CONSTANT(T, 113, -4.70088348734699134347906176097717782),
  681. BOOST_MATH_BIG_CONSTANT(T, 113, -2.36921550900925512951976617607678789),
  682. BOOST_MATH_BIG_CONSTANT(T, 113, -0.684322583796369508367726293719322866),
  683. BOOST_MATH_BIG_CONSTANT(T, 113, -0.126026534540165129870721937592996324),
  684. BOOST_MATH_BIG_CONSTANT(T, 113, -0.015636903921778316147260572008619549),
  685. BOOST_MATH_BIG_CONSTANT(T, 113, -0.00135442294754728549644376325814460807),
  686. BOOST_MATH_BIG_CONSTANT(T, 113, -0.842793965853572134365031384646117061e-4),
  687. BOOST_MATH_BIG_CONSTANT(T, 113, -0.385602133791111663372015460784978351e-5),
  688. BOOST_MATH_BIG_CONSTANT(T, 113, -0.130458500394692067189883214401478539e-6),
  689. BOOST_MATH_BIG_CONSTANT(T, 113, -0.315861074947230418778143153383660035e-8),
  690. BOOST_MATH_BIG_CONSTANT(T, 113, -0.500334720512030826996373077844707164e-10),
  691. BOOST_MATH_BIG_CONSTANT(T, 113, -0.420204769185233365849253969097184005e-12),
  692. };
  693. static const T Q[14] = {
  694. BOOST_MATH_BIG_CONSTANT(T, 113, 1),
  695. BOOST_MATH_BIG_CONSTANT(T, 113, 0.97663511666410096104783358493318814),
  696. BOOST_MATH_BIG_CONSTANT(T, 113, 0.40878780231201806504987368939673249),
  697. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0963890666609396058945084107597727252),
  698. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0142207619090854604824116070866614505),
  699. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00139010220902667918476773423995750877),
  700. BOOST_MATH_BIG_CONSTANT(T, 113, 0.940669540194694997889636696089994734e-4),
  701. BOOST_MATH_BIG_CONSTANT(T, 113, 0.458220848507517004399292480807026602e-5),
  702. BOOST_MATH_BIG_CONSTANT(T, 113, 0.16345521617741789012782420625435495e-6),
  703. BOOST_MATH_BIG_CONSTANT(T, 113, 0.414007452533083304371566316901024114e-8),
  704. BOOST_MATH_BIG_CONSTANT(T, 113, 0.68701473543366328016953742622661377e-10),
  705. BOOST_MATH_BIG_CONSTANT(T, 113, 0.603461891080716585087883971886075863e-12),
  706. BOOST_MATH_BIG_CONSTANT(T, 113, 0.294670713571839023181857795866134957e-16),
  707. BOOST_MATH_BIG_CONSTANT(T, 113, -0.147003914536437243143096875069813451e-18),
  708. };
  709. result = tools::evaluate_polynomial(P, T(s - 6)) / tools::evaluate_polynomial(Q, T(s - 6));
  710. result = 1 + exp(result);
  711. }
  712. else if(s < 17)
  713. {
  714. // Max error in interpolated form: 1.641e-32
  715. // Max error found at long double precision: 1.696121e-32
  716. static const T P[13] = {
  717. BOOST_MATH_BIG_CONSTANT(T, 113, -6.91319491921722925920883787894829678),
  718. BOOST_MATH_BIG_CONSTANT(T, 113, -3.65491257639481960248690596951049048),
  719. BOOST_MATH_BIG_CONSTANT(T, 113, -0.813557553449954526442644544105257881),
  720. BOOST_MATH_BIG_CONSTANT(T, 113, -0.0994317301685870959473658713841138083),
  721. BOOST_MATH_BIG_CONSTANT(T, 113, -0.00726896610245676520248617014211734906),
  722. BOOST_MATH_BIG_CONSTANT(T, 113, -0.000317253318715075854811266230916762929),
  723. BOOST_MATH_BIG_CONSTANT(T, 113, -0.66851422826636750855184211580127133e-5),
  724. BOOST_MATH_BIG_CONSTANT(T, 113, 0.879464154730985406003332577806849971e-7),
  725. BOOST_MATH_BIG_CONSTANT(T, 113, 0.113838903158254250631678791998294628e-7),
  726. BOOST_MATH_BIG_CONSTANT(T, 113, 0.379184410304927316385211327537817583e-9),
  727. BOOST_MATH_BIG_CONSTANT(T, 113, 0.612992858643904887150527613446403867e-11),
  728. BOOST_MATH_BIG_CONSTANT(T, 113, 0.347873737198164757035457841688594788e-13),
  729. BOOST_MATH_BIG_CONSTANT(T, 113, -0.289187187441625868404494665572279364e-15),
  730. };
  731. static const T Q[14] = {
  732. BOOST_MATH_BIG_CONSTANT(T, 113, 1),
  733. BOOST_MATH_BIG_CONSTANT(T, 113, 0.427310044448071818775721584949868806),
  734. BOOST_MATH_BIG_CONSTANT(T, 113, 0.074602514873055756201435421385243062),
  735. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00688651562174480772901425121653945942),
  736. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000360174847635115036351323894321880445),
  737. BOOST_MATH_BIG_CONSTANT(T, 113, 0.973556847713307543918865405758248777e-5),
  738. BOOST_MATH_BIG_CONSTANT(T, 113, -0.853455848314516117964634714780874197e-8),
  739. BOOST_MATH_BIG_CONSTANT(T, 113, -0.118203513654855112421673192194622826e-7),
  740. BOOST_MATH_BIG_CONSTANT(T, 113, -0.462521662511754117095006543363328159e-9),
  741. BOOST_MATH_BIG_CONSTANT(T, 113, -0.834212591919475633107355719369463143e-11),
  742. BOOST_MATH_BIG_CONSTANT(T, 113, -0.5354594751002702935740220218582929e-13),
  743. BOOST_MATH_BIG_CONSTANT(T, 113, 0.406451690742991192964889603000756203e-15),
  744. BOOST_MATH_BIG_CONSTANT(T, 113, 0.887948682401000153828241615760146728e-19),
  745. BOOST_MATH_BIG_CONSTANT(T, 113, -0.34980761098820347103967203948619072e-21),
  746. };
  747. result = tools::evaluate_polynomial(P, T(s - 10)) / tools::evaluate_polynomial(Q, T(s - 10));
  748. result = 1 + exp(result);
  749. }
  750. else if(s < 30)
  751. {
  752. // Max error in interpolated form: 1.563e-31
  753. // Max error found at long double precision: 1.562725e-31
  754. static const T P[13] = {
  755. BOOST_MATH_BIG_CONSTANT(T, 113, -11.7824798233959252791987402769438322),
  756. BOOST_MATH_BIG_CONSTANT(T, 113, -4.36131215284987731928174218354118102),
  757. BOOST_MATH_BIG_CONSTANT(T, 113, -0.732260980060982349410898496846972204),
  758. BOOST_MATH_BIG_CONSTANT(T, 113, -0.0744985185694913074484248803015717388),
  759. BOOST_MATH_BIG_CONSTANT(T, 113, -0.00517228281320594683022294996292250527),
  760. BOOST_MATH_BIG_CONSTANT(T, 113, -0.000260897206152101522569969046299309939),
  761. BOOST_MATH_BIG_CONSTANT(T, 113, -0.989553462123121764865178453128769948e-5),
  762. BOOST_MATH_BIG_CONSTANT(T, 113, -0.286916799741891410827712096608826167e-6),
  763. BOOST_MATH_BIG_CONSTANT(T, 113, -0.637262477796046963617949532211619729e-8),
  764. BOOST_MATH_BIG_CONSTANT(T, 113, -0.106796831465628373325491288787760494e-9),
  765. BOOST_MATH_BIG_CONSTANT(T, 113, -0.129343095511091870860498356205376823e-11),
  766. BOOST_MATH_BIG_CONSTANT(T, 113, -0.102397936697965977221267881716672084e-13),
  767. BOOST_MATH_BIG_CONSTANT(T, 113, -0.402663128248642002351627980255756363e-16),
  768. };
  769. static const T Q[14] = {
  770. BOOST_MATH_BIG_CONSTANT(T, 113, 1),
  771. BOOST_MATH_BIG_CONSTANT(T, 113, 0.311288325355705609096155335186466508),
  772. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0438318468940415543546769437752132748),
  773. BOOST_MATH_BIG_CONSTANT(T, 113, 0.00374396349183199548610264222242269536),
  774. BOOST_MATH_BIG_CONSTANT(T, 113, 0.000218707451200585197339671707189281302),
  775. BOOST_MATH_BIG_CONSTANT(T, 113, 0.927578767487930747532953583797351219e-5),
  776. BOOST_MATH_BIG_CONSTANT(T, 113, 0.294145760625753561951137473484889639e-6),
  777. BOOST_MATH_BIG_CONSTANT(T, 113, 0.704618586690874460082739479535985395e-8),
  778. BOOST_MATH_BIG_CONSTANT(T, 113, 0.126333332872897336219649130062221257e-9),
  779. BOOST_MATH_BIG_CONSTANT(T, 113, 0.16317315713773503718315435769352765e-11),
  780. BOOST_MATH_BIG_CONSTANT(T, 113, 0.137846712823719515148344938160275695e-13),
  781. BOOST_MATH_BIG_CONSTANT(T, 113, 0.580975420554224366450994232723910583e-16),
  782. BOOST_MATH_BIG_CONSTANT(T, 113, -0.291354445847552426900293580511392459e-22),
  783. BOOST_MATH_BIG_CONSTANT(T, 113, 0.73614324724785855925025452085443636e-25),
  784. };
  785. result = tools::evaluate_polynomial(P, T(s - 17)) / tools::evaluate_polynomial(Q, T(s - 17));
  786. result = 1 + exp(result);
  787. }
  788. else if(s < 74)
  789. {
  790. // Max error in interpolated form: 2.311e-27
  791. // Max error found at long double precision: 2.297544e-27
  792. static const T P[14] = {
  793. BOOST_MATH_BIG_CONSTANT(T, 113, -20.7944102007844314586649688802236072),
  794. BOOST_MATH_BIG_CONSTANT(T, 113, -4.95759941987499442499908748130192187),
  795. BOOST_MATH_BIG_CONSTANT(T, 113, -0.563290752832461751889194629200298688),
  796. BOOST_MATH_BIG_CONSTANT(T, 113, -0.0406197001137935911912457120706122877),
  797. BOOST_MATH_BIG_CONSTANT(T, 113, -0.0020846534789473022216888863613422293),
  798. BOOST_MATH_BIG_CONSTANT(T, 113, -0.808095978462109173749395599401375667e-4),
  799. BOOST_MATH_BIG_CONSTANT(T, 113, -0.244706022206249301640890603610060959e-5),
  800. BOOST_MATH_BIG_CONSTANT(T, 113, -0.589477682919645930544382616501666572e-7),
  801. BOOST_MATH_BIG_CONSTANT(T, 113, -0.113699573675553496343617442433027672e-8),
  802. BOOST_MATH_BIG_CONSTANT(T, 113, -0.174767860183598149649901223128011828e-10),
  803. BOOST_MATH_BIG_CONSTANT(T, 113, -0.210051620306761367764549971980026474e-12),
  804. BOOST_MATH_BIG_CONSTANT(T, 113, -0.189187969537370950337212675466400599e-14),
  805. BOOST_MATH_BIG_CONSTANT(T, 113, -0.116313253429564048145641663778121898e-16),
  806. BOOST_MATH_BIG_CONSTANT(T, 113, -0.376708747782400769427057630528578187e-19),
  807. };
  808. static const T Q[16] = {
  809. BOOST_MATH_BIG_CONSTANT(T, 113, 1),
  810. BOOST_MATH_BIG_CONSTANT(T, 113, 0.205076752981410805177554569784219717),
  811. BOOST_MATH_BIG_CONSTANT(T, 113, 0.0202526722696670378999575738524540269),
  812. BOOST_MATH_BIG_CONSTANT(T, 113, 0.001278305290005994980069466658219057),
  813. BOOST_MATH_BIG_CONSTANT(T, 113, 0.576404779858501791742255670403304787e-4),
  814. BOOST_MATH_BIG_CONSTANT(T, 113, 0.196477049872253010859712483984252067e-5),
  815. BOOST_MATH_BIG_CONSTANT(T, 113, 0.521863830500876189501054079974475762e-7),
  816. BOOST_MATH_BIG_CONSTANT(T, 113, 0.109524209196868135198775445228552059e-8),
  817. BOOST_MATH_BIG_CONSTANT(T, 113, 0.181698713448644481083966260949267825e-10),
  818. BOOST_MATH_BIG_CONSTANT(T, 113, 0.234793316975091282090312036524695562e-12),
  819. BOOST_MATH_BIG_CONSTANT(T, 113, 0.227490441461460571047545264251399048e-14),
  820. BOOST_MATH_BIG_CONSTANT(T, 113, 0.151500292036937400913870642638520668e-16),
  821. BOOST_MATH_BIG_CONSTANT(T, 113, 0.543475775154780935815530649335936121e-19),
  822. BOOST_MATH_BIG_CONSTANT(T, 113, 0.241647013434111434636554455083309352e-28),
  823. BOOST_MATH_BIG_CONSTANT(T, 113, -0.557103423021951053707162364713587374e-31),
  824. BOOST_MATH_BIG_CONSTANT(T, 113, 0.618708773442584843384712258199645166e-34),
  825. };
  826. result = tools::evaluate_polynomial(P, T(s - 30)) / tools::evaluate_polynomial(Q, T(s - 30));
  827. result = 1 + exp(result);
  828. }
  829. else if(s < 117)
  830. {
  831. result = 1 + pow(T(2), -s);
  832. }
  833. else
  834. {
  835. result = 1;
  836. }
  837. return result;
  838. }
  839. template <class T, class Policy, class Tag>
  840. T zeta_imp(T s, T sc, const Policy& pol, const Tag& tag)
  841. {
  842. BOOST_MATH_STD_USING
  843. if(sc == 0)
  844. return policies::raise_pole_error<T>(
  845. "boost::math::zeta<%1%>",
  846. "Evaluation of zeta function at pole %1%",
  847. s, pol);
  848. T result;
  849. if(fabs(s) < tools::root_epsilon<T>())
  850. {
  851. result = -0.5f - constants::log_root_two_pi<T, Policy>() * s;
  852. }
  853. else if(s < 0)
  854. {
  855. std::swap(s, sc);
  856. if(floor(sc/2) == sc/2)
  857. result = 0;
  858. else
  859. {
  860. result = boost::math::sin_pi(0.5f * sc, pol)
  861. * 2 * pow(2 * constants::pi<T>(), -s)
  862. * boost::math::tgamma(s, pol)
  863. * zeta_imp(s, sc, pol, tag);
  864. }
  865. }
  866. else
  867. {
  868. result = zeta_imp_prec(s, sc, pol, tag);
  869. }
  870. return result;
  871. }
  872. template <class T, class Policy, class tag>
  873. struct zeta_initializer
  874. {
  875. struct init
  876. {
  877. init()
  878. {
  879. do_init(tag());
  880. }
  881. static void do_init(const mpl::int_<0>&){}
  882. static void do_init(const mpl::int_<53>&){}
  883. static void do_init(const mpl::int_<64>&)
  884. {
  885. boost::math::zeta(static_cast<T>(0.5), Policy());
  886. boost::math::zeta(static_cast<T>(1.5), Policy());
  887. boost::math::zeta(static_cast<T>(3.5), Policy());
  888. boost::math::zeta(static_cast<T>(6.5), Policy());
  889. boost::math::zeta(static_cast<T>(14.5), Policy());
  890. boost::math::zeta(static_cast<T>(40.5), Policy());
  891. }
  892. static void do_init(const mpl::int_<113>&)
  893. {
  894. boost::math::zeta(static_cast<T>(0.5), Policy());
  895. boost::math::zeta(static_cast<T>(1.5), Policy());
  896. boost::math::zeta(static_cast<T>(3.5), Policy());
  897. boost::math::zeta(static_cast<T>(5.5), Policy());
  898. boost::math::zeta(static_cast<T>(9.5), Policy());
  899. boost::math::zeta(static_cast<T>(16.5), Policy());
  900. boost::math::zeta(static_cast<T>(25), Policy());
  901. boost::math::zeta(static_cast<T>(70), Policy());
  902. }
  903. void force_instantiate()const{}
  904. };
  905. static const init initializer;
  906. static void force_instantiate()
  907. {
  908. initializer.force_instantiate();
  909. }
  910. };
  911. template <class T, class Policy, class tag>
  912. const typename zeta_initializer<T, Policy, tag>::init zeta_initializer<T, Policy, tag>::initializer;
  913. } // detail
  914. template <class T, class Policy>
  915. inline typename tools::promote_args<T>::type zeta(T s, const Policy&)
  916. {
  917. typedef typename tools::promote_args<T>::type result_type;
  918. typedef typename policies::evaluation<result_type, Policy>::type value_type;
  919. typedef typename policies::precision<result_type, Policy>::type precision_type;
  920. typedef typename policies::normalise<
  921. Policy,
  922. policies::promote_float<false>,
  923. policies::promote_double<false>,
  924. policies::discrete_quantile<>,
  925. policies::assert_undefined<> >::type forwarding_policy;
  926. typedef typename mpl::if_<
  927. mpl::less_equal<precision_type, mpl::int_<0> >,
  928. mpl::int_<0>,
  929. typename mpl::if_<
  930. mpl::less_equal<precision_type, mpl::int_<53> >,
  931. mpl::int_<53>, // double
  932. typename mpl::if_<
  933. mpl::less_equal<precision_type, mpl::int_<64> >,
  934. mpl::int_<64>, // 80-bit long double
  935. typename mpl::if_<
  936. mpl::less_equal<precision_type, mpl::int_<113> >,
  937. mpl::int_<113>, // 128-bit long double
  938. mpl::int_<0> // too many bits, use generic version.
  939. >::type
  940. >::type
  941. >::type
  942. >::type tag_type;
  943. //typedef mpl::int_<0> tag_type;
  944. detail::zeta_initializer<value_type, forwarding_policy, tag_type>::force_instantiate();
  945. return policies::checked_narrowing_cast<result_type, forwarding_policy>(detail::zeta_imp(
  946. static_cast<value_type>(s),
  947. static_cast<value_type>(1 - static_cast<value_type>(s)),
  948. forwarding_policy(),
  949. tag_type()), "boost::math::zeta<%1%>(%1%)");
  950. }
  951. template <class T>
  952. inline typename tools::promote_args<T>::type zeta(T s)
  953. {
  954. return zeta(s, policies::policy<>());
  955. }
  956. }} // namespaces
  957. #endif // BOOST_MATH_ZETA_HPP