Chris@16: // Copyright John Maddock 2010, 2012. Chris@16: // Copyright Paul A. Bristow 2011, 2012. Chris@16: Chris@16: // Use, modification and distribution are subject to the Chris@16: // Boost Software License, Version 1.0. (See accompanying file Chris@16: // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) Chris@16: Chris@16: #ifndef BOOST_MATH_CALCULATE_CONSTANTS_CONSTANTS_INCLUDED Chris@16: #define BOOST_MATH_CALCULATE_CONSTANTS_CONSTANTS_INCLUDED Chris@16: Chris@16: #include Chris@16: Chris@16: namespace boost{ namespace math{ namespace constants{ namespace detail{ Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_pi::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: Chris@16: return ldexp(acos(T(0)), 1); Chris@16: Chris@16: /* Chris@16: // Although this code works well, it's usually more accurate to just call acos Chris@16: // and access the number types own representation of PI which is usually calculated Chris@16: // at slightly higher precision... Chris@16: Chris@16: T result; Chris@16: T a = 1; Chris@16: T b; Chris@16: T A(a); Chris@16: T B = 0.5f; Chris@16: T D = 0.25f; Chris@16: Chris@16: T lim; Chris@16: lim = boost::math::tools::epsilon(); Chris@16: Chris@16: unsigned k = 1; Chris@16: Chris@16: do Chris@16: { Chris@16: result = A + B; Chris@16: result = ldexp(result, -2); Chris@16: b = sqrt(B); Chris@16: a += b; Chris@16: a = ldexp(a, -1); Chris@16: A = a * a; Chris@16: B = A - result; Chris@16: B = ldexp(B, 1); Chris@16: result = A - B; Chris@16: bool neg = boost::math::sign(result) < 0; Chris@16: if(neg) Chris@16: result = -result; Chris@16: if(result <= lim) Chris@16: break; Chris@16: if(neg) Chris@16: result = -result; Chris@16: result = ldexp(result, k - 1); Chris@16: D -= result; Chris@16: ++k; Chris@16: lim = ldexp(lim, 1); Chris@16: } Chris@16: while(true); Chris@16: Chris@16: result = B / D; Chris@16: return result; Chris@16: */ Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_two_pi::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: return 2 * pi > >(); Chris@16: } Chris@16: Chris@16: template // 2 / pi Chris@16: template Chris@16: inline T constant_two_div_pi::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: return 2 / pi > >(); Chris@16: } Chris@16: Chris@16: template // sqrt(2/pi) Chris@16: template Chris@16: inline T constant_root_two_div_pi::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return sqrt((2 / pi > >())); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_one_div_two_pi::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: return 1 / two_pi > >(); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_root_pi::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return sqrt(pi > >()); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_root_half_pi::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return sqrt(pi > >() / 2); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_root_two_pi::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return sqrt(two_pi > >()); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_log_root_two_pi::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return log(root_two_pi > >()); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_root_ln_four::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return sqrt(log(static_cast(4))); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_e::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: // Chris@16: // Although we can clearly calculate this from first principles, this hooks into Chris@16: // T's own notion of e, which hopefully will more accurate than one calculated to Chris@16: // a few epsilon: Chris@16: // Chris@16: BOOST_MATH_STD_USING Chris@16: return exp(static_cast(1)); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_half::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: return static_cast(1) / static_cast(2); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_euler::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: // Chris@16: // This is the method described in: Chris@16: // "Some New Algorithms for High-Precision Computation of Euler's Constant" Chris@16: // Richard P Brent and Edwin M McMillan. Chris@16: // Mathematics of Computation, Volume 34, Number 149, Jan 1980, pages 305-312. Chris@16: // See equation 17 with p = 2. Chris@16: // Chris@16: T n = 3 + (M ? (std::min)(M, tools::digits()) : tools::digits()) / 4; Chris@16: T lim = M ? ldexp(T(1), 1 - (std::min)(M, tools::digits())) : tools::epsilon(); Chris@16: T lnn = log(n); Chris@16: T term = 1; Chris@16: T N = -lnn; Chris@16: T D = 1; Chris@16: T Hk = 0; Chris@16: T one = 1; Chris@16: Chris@16: for(unsigned k = 1;; ++k) Chris@16: { Chris@16: term *= n * n; Chris@16: term /= k * k; Chris@16: Hk += one / k; Chris@16: N += term * (Hk - lnn); Chris@16: D += term; Chris@16: Chris@16: if(term < D * lim) Chris@16: break; Chris@16: } Chris@16: return N / D; Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_euler_sqr::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return euler > >() Chris@16: * euler > >(); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_one_div_euler::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return static_cast(1) Chris@16: / euler > >(); Chris@16: } Chris@16: Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_root_two::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return sqrt(static_cast(2)); Chris@16: } Chris@16: Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_root_three::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return sqrt(static_cast(3)); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_half_root_two::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return sqrt(static_cast(2)) / 2; Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_ln_two::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: // Chris@16: // Although there are good ways to calculate this from scratch, this hooks into Chris@16: // T's own notion of log(2) which will hopefully be accurate to the full precision Chris@16: // of T: Chris@16: // Chris@16: BOOST_MATH_STD_USING Chris@16: return log(static_cast(2)); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_ln_ten::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return log(static_cast(10)); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_ln_ln_two::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return log(log(static_cast(2))); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_third::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return static_cast(1) / static_cast(3); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_twothirds::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return static_cast(2) / static_cast(3); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_two_thirds::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return static_cast(2) / static_cast(3); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_three_quarters::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return static_cast(3) / static_cast(4); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_pi_minus_three::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: return pi > >() - static_cast(3); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_four_minus_pi::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: return static_cast(4) - pi > >(); Chris@16: } Chris@16: Chris@101: //template Chris@101: //template Chris@101: //inline T constant_pow23_four_minus_pi::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@101: //{ Chris@101: // BOOST_MATH_STD_USING Chris@101: // return pow(four_minus_pi > >(), static_cast(1.5)); Chris@101: //} Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_exp_minus_half::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return exp(static_cast(-0.5)); Chris@16: } Chris@16: Chris@16: // Pi Chris@16: template Chris@16: template Chris@16: inline T constant_one_div_root_two::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: return static_cast(1) / root_two > >(); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_one_div_root_pi::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: return static_cast(1) / root_pi > >(); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_one_div_root_two_pi::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: return static_cast(1) / root_two_pi > >(); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_root_one_div_pi::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return sqrt(static_cast(1) / pi > >()); Chris@16: } Chris@16: Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_four_thirds_pi::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return pi > >() * static_cast(4) / static_cast(3); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_half_pi::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return pi > >() / static_cast(2); Chris@16: } Chris@16: Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_third_pi::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return pi > >() / static_cast(3); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_sixth_pi::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return pi > >() / static_cast(6); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_two_thirds_pi::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return pi > >() * static_cast(2) / static_cast(3); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_three_quarters_pi::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return pi > >() * static_cast(3) / static_cast(4); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_pi_pow_e::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return pow(pi > >(), e > >()); // Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_pi_sqr::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return pi > >() Chris@16: * pi > >() ; // Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_pi_sqr_div_six::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return pi > >() Chris@16: * pi > >() Chris@16: / static_cast(6); // Chris@16: } Chris@16: Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_pi_cubed::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return pi > >() Chris@16: * pi > >() Chris@16: * pi > >() Chris@16: ; // Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_cbrt_pi::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return pow(pi > >(), static_cast(1)/ static_cast(3)); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_one_div_cbrt_pi::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return static_cast(1) Chris@16: / pow(pi > >(), static_cast(1)/ static_cast(3)); Chris@16: } Chris@16: Chris@16: // Euler's e Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_e_pow_pi::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return pow(e > >(), pi > >()); // Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_root_e::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return sqrt(e > >()); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_log10_e::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return log10(e > >()); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_one_div_log10_e::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return static_cast(1) / Chris@16: log10(e > >()); Chris@16: } Chris@16: Chris@16: // Trigonometric Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_degree::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return pi > >() Chris@16: / static_cast(180) Chris@16: ; // Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_radian::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return static_cast(180) Chris@16: / pi > >() Chris@16: ; // Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_sin_one::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return sin(static_cast(1)) ; // Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_cos_one::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return cos(static_cast(1)) ; // Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_sinh_one::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return sinh(static_cast(1)) ; // Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_cosh_one::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return cosh(static_cast(1)) ; // Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_phi::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return (static_cast(1) + sqrt(static_cast(5)) )/static_cast(2) ; // Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_ln_phi::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: //return log(phi > >()); // ??? Chris@16: return log((static_cast(1) + sqrt(static_cast(5)) )/static_cast(2) ); Chris@16: } Chris@16: template Chris@16: template Chris@16: inline T constant_one_div_ln_phi::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: return static_cast(1) / Chris@16: log((static_cast(1) + sqrt(static_cast(5)) )/static_cast(2) ); Chris@16: } Chris@16: Chris@16: // Zeta Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_zeta_two::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: Chris@16: return pi > >() Chris@16: * pi > >() Chris@16: /static_cast(6); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_zeta_three::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: // http://mathworld.wolfram.com/AperysConstant.html Chris@16: // http://en.wikipedia.org/wiki/Mathematical_constant Chris@16: Chris@16: // http://oeis.org/A002117/constant Chris@16: //T zeta3("1.20205690315959428539973816151144999076" Chris@16: // "4986292340498881792271555341838205786313" Chris@16: // "09018645587360933525814619915"); Chris@16: Chris@16: //"1.202056903159594285399738161511449990, 76498629234049888179227155534183820578631309018645587360933525814619915" A002117 Chris@16: // 1.202056903159594285399738161511449990, 76498629234049888179227155534183820578631309018645587360933525814619915780, +00); Chris@16: //"1.2020569031595942 double Chris@16: // http://www.spaennare.se/SSPROG/ssnum.pdf // section 11, Algorithm for Apery's constant zeta(3). Chris@16: // Programs to Calculate some Mathematical Constants to Large Precision, Document Version 1.50 Chris@16: Chris@16: // by Stefan Spannare September 19, 2007 Chris@16: // zeta(3) = 1/64 * sum Chris@16: BOOST_MATH_STD_USING Chris@16: T n_fact=static_cast(1); // build n! for n = 0. Chris@16: T sum = static_cast(77); // Start with n = 0 case. Chris@16: // for n = 0, (77/1) /64 = 1.203125 Chris@16: //double lim = std::numeric_limits::epsilon(); Chris@16: T lim = N ? ldexp(T(1), 1 - (std::min)(N, tools::digits())) : tools::epsilon(); Chris@16: for(unsigned int n = 1; n < 40; ++n) Chris@16: { // three to five decimal digits per term, so 40 should be plenty for 100 decimal digits. Chris@16: //cout << "n = " << n << endl; Chris@16: n_fact *= n; // n! Chris@16: T n_fact_p10 = n_fact * n_fact * n_fact * n_fact * n_fact * n_fact * n_fact * n_fact * n_fact * n_fact; // (n!)^10 Chris@16: T num = ((205 * n * n) + (250 * n) + 77) * n_fact_p10; // 205n^2 + 250n + 77 Chris@16: // int nn = (2 * n + 1); Chris@16: // T d = factorial(nn); // inline factorial. Chris@16: T d = 1; Chris@16: for(unsigned int i = 1; i <= (n+n + 1); ++i) // (2n + 1) Chris@16: { Chris@16: d *= i; Chris@16: } Chris@16: T den = d * d * d * d * d; // [(2n+1)!]^5 Chris@16: //cout << "den = " << den << endl; Chris@16: T term = num/den; Chris@16: if (n % 2 != 0) Chris@16: { //term *= -1; Chris@16: sum -= term; Chris@16: } Chris@16: else Chris@16: { Chris@16: sum += term; Chris@16: } Chris@16: //cout << "term = " << term << endl; Chris@16: //cout << "sum/64 = " << sum/64 << endl; Chris@16: if(abs(term) < lim) Chris@16: { Chris@16: break; Chris@16: } Chris@16: } Chris@16: return sum / 64; Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_catalan::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { // http://oeis.org/A006752/constant Chris@16: //T c("0.915965594177219015054603514932384110774" Chris@16: //"149374281672134266498119621763019776254769479356512926115106248574"); Chris@16: Chris@16: // 9.159655941772190150546035149323841107, 74149374281672134266498119621763019776254769479356512926115106248574422619, -01); Chris@16: Chris@16: // This is equation (entry) 31 from Chris@16: // http://www-2.cs.cmu.edu/~adamchik/articles/catalan/catalan.htm Chris@16: // See also http://www.mpfr.org/algorithms.pdf Chris@16: BOOST_MATH_STD_USING Chris@16: T k_fact = 1; Chris@16: T tk_fact = 1; Chris@16: T sum = 1; Chris@16: T term; Chris@16: T lim = N ? ldexp(T(1), 1 - (std::min)(N, tools::digits())) : tools::epsilon(); Chris@16: Chris@16: for(unsigned k = 1;; ++k) Chris@16: { Chris@16: k_fact *= k; Chris@16: tk_fact *= (2 * k) * (2 * k - 1); Chris@16: term = k_fact * k_fact / (tk_fact * (2 * k + 1) * (2 * k + 1)); Chris@16: sum += term; Chris@16: if(term < lim) Chris@16: { Chris@16: break; Chris@16: } Chris@16: } Chris@16: return boost::math::constants::pi >() Chris@16: * log(2 + boost::math::constants::root_three >()) Chris@16: / 8 Chris@16: + 3 * sum / 8; Chris@16: } Chris@16: Chris@16: namespace khinchin_detail{ Chris@16: Chris@16: template Chris@16: T zeta_polynomial_series(T s, T sc, int digits) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: // Chris@16: // This is algorithm 3 from: Chris@16: // Chris@16: // "An Efficient Algorithm for the Riemann Zeta Function", P. Borwein, Chris@16: // Canadian Mathematical Society, Conference Proceedings, 2000. Chris@16: // See: http://www.cecm.sfu.ca/personal/pborwein/PAPERS/P155.pdf Chris@16: // Chris@16: BOOST_MATH_STD_USING Chris@16: int n = (digits * 19) / 53; Chris@16: T sum = 0; Chris@16: T two_n = ldexp(T(1), n); Chris@16: int ej_sign = 1; Chris@16: for(int j = 0; j < n; ++j) Chris@16: { Chris@16: sum += ej_sign * -two_n / pow(T(j + 1), s); Chris@16: ej_sign = -ej_sign; Chris@16: } Chris@16: T ej_sum = 1; Chris@16: T ej_term = 1; Chris@16: for(int j = n; j <= 2 * n - 1; ++j) Chris@16: { Chris@16: sum += ej_sign * (ej_sum - two_n) / pow(T(j + 1), s); Chris@16: ej_sign = -ej_sign; Chris@16: ej_term *= 2 * n - j; Chris@16: ej_term /= j - n + 1; Chris@16: ej_sum += ej_term; Chris@16: } Chris@16: return -sum / (two_n * (1 - pow(T(2), sc))); Chris@16: } Chris@16: Chris@16: template Chris@16: T khinchin(int digits) Chris@16: { Chris@16: BOOST_MATH_STD_USING Chris@16: T sum = 0; Chris@16: T term; Chris@16: T lim = ldexp(T(1), 1-digits); Chris@16: T factor = 0; Chris@16: unsigned last_k = 1; Chris@16: T num = 1; Chris@16: for(unsigned n = 1;; ++n) Chris@16: { Chris@16: for(unsigned k = last_k; k <= 2 * n - 1; ++k) Chris@16: { Chris@16: factor += num / k; Chris@16: num = -num; Chris@16: } Chris@16: last_k = 2 * n; Chris@16: term = (zeta_polynomial_series(T(2 * n), T(1 - T(2 * n)), digits) - 1) * factor / n; Chris@16: sum += term; Chris@16: if(term < lim) Chris@16: break; Chris@16: } Chris@16: return exp(sum / boost::math::constants::ln_two >()); Chris@16: } Chris@16: Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_khinchin::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: int n = N ? (std::min)(N, tools::digits()) : tools::digits(); Chris@16: return khinchin_detail::khinchin(n); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_extreme_value_skewness::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { // from e_float constants.cpp Chris@16: // Mathematica: N[12 Sqrt[6] Zeta[3]/Pi^3, 1101] Chris@16: BOOST_MATH_STD_USING Chris@16: T ev(12 * sqrt(static_cast(6)) * zeta_three > >() Chris@16: / pi_cubed > >() ); Chris@16: Chris@16: //T ev( Chris@16: //"1.1395470994046486574927930193898461120875997958365518247216557100852480077060706857071875468869385150" Chris@16: //"1894272048688553376986765366075828644841024041679714157616857834895702411080704529137366329462558680" Chris@16: //"2015498788776135705587959418756809080074611906006528647805347822929577145038743873949415294942796280" Chris@16: //"0895597703063466053535550338267721294164578901640163603544404938283861127819804918174973533694090594" Chris@16: //"3094963822672055237678432023017824416203652657301470473548274848068762500300316769691474974950757965" Chris@16: //"8640779777748741897542093874605477776538884083378029488863880220988107155275203245233994097178778984" Chris@16: //"3488995668362387892097897322246698071290011857605809901090220903955815127463328974447572119951192970" Chris@16: //"3684453635456559086126406960279692862247058250100678008419431185138019869693206366891639436908462809" Chris@16: //"9756051372711251054914491837034685476095423926553367264355374652153595857163724698198860485357368964" Chris@16: //"3807049634423621246870868566707915720704996296083373077647528285782964567312903914752617978405994377" Chris@16: //"9064157147206717895272199736902453130842229559980076472936976287378945035706933650987259357729800315"); Chris@16: Chris@16: return ev; Chris@16: } Chris@16: Chris@16: namespace detail{ Chris@16: // Chris@16: // Calculation of the Glaisher constant depends upon calculating the Chris@16: // derivative of the zeta function at 2, we can then use the relation: Chris@16: // zeta'(2) = 1/6 pi^2 [euler + ln(2pi)-12ln(A)] Chris@16: // To get the constant A. Chris@16: // See equation 45 at http://mathworld.wolfram.com/RiemannZetaFunction.html. Chris@16: // Chris@16: // The derivative of the zeta function is computed by direct differentiation Chris@16: // of the relation: Chris@16: // (1-2^(1-s))zeta(s) = SUM(n=0, INF){ (-n)^n / (n+1)^s } Chris@16: // Which gives us 2 slowly converging but alternating sums to compute, Chris@16: // for this we use Algorithm 1 from "Convergent Acceleration of Alternating Series", Chris@16: // Henri Cohen, Fernando Rodriguez Villegas and Don Zagier, Experimental Mathematics 9:1 (1999). Chris@16: // See http://www.math.utexas.edu/users/villegas/publications/conv-accel.pdf Chris@16: // Chris@16: template Chris@16: T zeta_series_derivative_2(unsigned digits) Chris@16: { Chris@16: // Derivative of the series part, evaluated at 2: Chris@16: BOOST_MATH_STD_USING Chris@16: int n = digits * 301 * 13 / 10000; Chris@16: boost::math::itrunc((std::numeric_limits::digits10 + 1) * 1.3); Chris@16: T d = pow(3 + sqrt(T(8)), n); Chris@16: d = (d + 1 / d) / 2; Chris@16: T b = -1; Chris@16: T c = -d; Chris@16: T s = 0; Chris@16: for(int k = 0; k < n; ++k) Chris@16: { Chris@16: T a = -log(T(k+1)) / ((k+1) * (k+1)); Chris@16: c = b - c; Chris@16: s = s + c * a; Chris@16: b = (k + n) * (k - n) * b / ((k + T(0.5f)) * (k + 1)); Chris@16: } Chris@16: return s / d; Chris@16: } Chris@16: Chris@16: template Chris@16: T zeta_series_2(unsigned digits) Chris@16: { Chris@16: // Series part of zeta at 2: Chris@16: BOOST_MATH_STD_USING Chris@16: int n = digits * 301 * 13 / 10000; Chris@16: T d = pow(3 + sqrt(T(8)), n); Chris@16: d = (d + 1 / d) / 2; Chris@16: T b = -1; Chris@16: T c = -d; Chris@16: T s = 0; Chris@16: for(int k = 0; k < n; ++k) Chris@16: { Chris@16: T a = T(1) / ((k + 1) * (k + 1)); Chris@16: c = b - c; Chris@16: s = s + c * a; Chris@16: b = (k + n) * (k - n) * b / ((k + T(0.5f)) * (k + 1)); Chris@16: } Chris@16: return s / d; Chris@16: } Chris@16: Chris@16: template Chris@16: inline T zeta_series_lead_2() Chris@16: { Chris@16: // lead part at 2: Chris@16: return 2; Chris@16: } Chris@16: Chris@16: template Chris@16: inline T zeta_series_derivative_lead_2() Chris@16: { Chris@16: // derivative of lead part at 2: Chris@16: return -2 * boost::math::constants::ln_two(); Chris@16: } Chris@16: Chris@16: template Chris@16: inline T zeta_derivative_2(unsigned n) Chris@16: { Chris@16: // zeta derivative at 2: Chris@16: return zeta_series_derivative_2(n) * zeta_series_lead_2() Chris@16: + zeta_series_derivative_lead_2() * zeta_series_2(n); Chris@16: } Chris@16: Chris@16: } // namespace detail Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_glaisher::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { Chris@16: Chris@16: BOOST_MATH_STD_USING Chris@16: typedef policies::policy > forwarding_policy; Chris@16: int n = N ? (std::min)(N, tools::digits()) : tools::digits(); Chris@16: T v = detail::zeta_derivative_2(n); Chris@16: v *= 6; Chris@16: v /= boost::math::constants::pi() * boost::math::constants::pi(); Chris@16: v -= boost::math::constants::euler(); Chris@16: v -= log(2 * boost::math::constants::pi()); Chris@16: v /= -12; Chris@16: return exp(v); Chris@16: Chris@16: /* Chris@16: // from http://mpmath.googlecode.com/svn/data/glaisher.txt Chris@16: // 20,000 digits of the Glaisher-Kinkelin constant A = exp(1/2 - zeta'(-1)) Chris@16: // Computed using A = exp((6 (-zeta'(2))/pi^2 + log 2 pi + gamma)/12) Chris@16: // with Euler-Maclaurin summation for zeta'(2). Chris@16: T g( Chris@16: "1.282427129100622636875342568869791727767688927325001192063740021740406308858826" Chris@16: "46112973649195820237439420646120399000748933157791362775280404159072573861727522" Chris@16: "14334327143439787335067915257366856907876561146686449997784962754518174312394652" Chris@16: "76128213808180219264516851546143919901083573730703504903888123418813674978133050" Chris@16: "93770833682222494115874837348064399978830070125567001286994157705432053927585405" Chris@16: "81731588155481762970384743250467775147374600031616023046613296342991558095879293" Chris@16: "36343887288701988953460725233184702489001091776941712153569193674967261270398013" Chris@16: "52652668868978218897401729375840750167472114895288815996668743164513890306962645" Chris@16: "59870469543740253099606800842447417554061490189444139386196089129682173528798629" Chris@16: "88434220366989900606980888785849587494085307347117090132667567503310523405221054" Chris@16: "14176776156308191919997185237047761312315374135304725819814797451761027540834943" Chris@16: "14384965234139453373065832325673954957601692256427736926358821692159870775858274" Chris@16: "69575162841550648585890834128227556209547002918593263079373376942077522290940187"); Chris@16: Chris@16: return g; Chris@16: */ Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_rayleigh_skewness::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { // From e_float Chris@16: // 1100 digits of the Rayleigh distribution skewness Chris@16: // Mathematica: N[2 Sqrt[Pi] (Pi - 3)/((4 - Pi)^(3/2)), 1100] Chris@16: Chris@16: BOOST_MATH_STD_USING Chris@16: T rs(2 * root_pi > >() Chris@16: * pi_minus_three > >() Chris@16: / pow(four_minus_pi > >(), static_cast(3./2)) Chris@16: ); Chris@16: // 6.31110657818937138191899351544227779844042203134719497658094585692926819617473725459905027032537306794400047264, Chris@16: Chris@16: //"0.6311106578189371381918993515442277798440422031347194976580945856929268196174737254599050270325373067" Chris@16: //"9440004726436754739597525250317640394102954301685809920213808351450851396781817932734836994829371322" Chris@16: //"5797376021347531983451654130317032832308462278373358624120822253764532674177325950686466133508511968" Chris@16: //"2389168716630349407238090652663422922072397393006683401992961569208109477307776249225072042971818671" Chris@16: //"4058887072693437217879039875871765635655476241624825389439481561152126886932506682176611183750503553" Chris@16: //"1218982627032068396407180216351425758181396562859085306247387212297187006230007438534686340210168288" Chris@16: //"8956816965453815849613622117088096547521391672977226658826566757207615552041767516828171274858145957" Chris@16: //"6137539156656005855905288420585194082284972984285863898582313048515484073396332610565441264220790791" Chris@16: //"0194897267890422924599776483890102027823328602965235306539844007677157873140562950510028206251529523" Chris@16: //"7428049693650605954398446899724157486062545281504433364675815915402937209673727753199567661561209251" Chris@16: //"4695589950526053470201635372590001578503476490223746511106018091907936826431407434894024396366284848"); ; Chris@16: return rs; Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_rayleigh_kurtosis_excess::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { // - (6 Pi^2 - 24 Pi + 16)/((Pi - 4)^2) Chris@16: // Might provide and calculate this using pi_minus_four. Chris@16: BOOST_MATH_STD_USING Chris@16: return - (((static_cast(6) * pi > >() Chris@16: * pi > >()) Chris@16: - (static_cast(24) * pi > >()) + static_cast(16) ) Chris@16: / Chris@16: ((pi > >() - static_cast(4)) Chris@16: * (pi > >() - static_cast(4))) Chris@16: ); Chris@16: } Chris@16: Chris@16: template Chris@16: template Chris@16: inline T constant_rayleigh_kurtosis::compute(BOOST_MATH_EXPLICIT_TEMPLATE_TYPE_SPEC(mpl::int_)) Chris@16: { // 3 - (6 Pi^2 - 24 Pi + 16)/((Pi - 4)^2) Chris@16: // Might provide and calculate this using pi_minus_four. Chris@16: BOOST_MATH_STD_USING Chris@16: return static_cast(3) - (((static_cast(6) * pi > >() Chris@16: * pi > >()) Chris@16: - (static_cast(24) * pi > >()) + static_cast(16) ) Chris@16: / Chris@16: ((pi > >() - static_cast(4)) Chris@16: * (pi > >() - static_cast(4))) Chris@16: ); Chris@16: } Chris@16: Chris@16: }}}} // namespaces Chris@16: Chris@16: #endif // BOOST_MATH_CALCULATE_CONSTANTS_CONSTANTS_INCLUDED