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- // Copyright Christopher Kormanyos 2002 - 2013.
- // Copyright 2011 - 2013 John Maddock.
- // Distributed under the Boost Software License, Version 1.0.
- // (See accompanying file LICENSE_1_0.txt or copy at
- // http://www.boost.org/LICENSE_1_0.txt)
- // This work is based on an earlier work:
- // "Algorithm 910: A Portable C++ Multiple-Precision System for Special-Function Calculations",
- // in ACM TOMS, {VOL 37, ISSUE 4, (February 2011)} (C) ACM, 2011. http://doi.acm.org/10.1145/1916461.1916469
- //
- // This file has no include guards or namespaces - it's expanded inline inside default_ops.hpp
- //
- #ifdef BOOST_MSVC
- #pragma warning(push)
- #pragma warning(disable : 6326) // comparison of two constants
- #pragma warning(disable : 4127) // conditional expression is constant
- #endif
- #include <boost/core/no_exceptions_support.hpp> // BOOST_TRY
- namespace detail {
- template <typename T, typename U>
- inline void pow_imp(T& result, const T& t, const U& p, const std::integral_constant<bool, false>&)
- {
- // Compute the pure power of typename T t^p.
- // Use the S-and-X binary method, as described in
- // D. E. Knuth, "The Art of Computer Programming", Vol. 2,
- // Section 4.6.3 . The resulting computational complexity
- // is order log2[abs(p)].
- using int_type = typename boost::multiprecision::detail::canonical<U, T>::type;
- if (&result == &t)
- {
- T temp;
- pow_imp(temp, t, p, std::integral_constant<bool, false>());
- result = temp;
- return;
- }
- // This will store the result.
- if (U(p % U(2)) != U(0))
- {
- result = t;
- }
- else
- result = int_type(1);
- U p2(p);
- // The variable x stores the binary powers of t.
- T x(t);
- while (U(p2 /= 2) != U(0))
- {
- // Square x for each binary power.
- eval_multiply(x, x);
- const bool has_binary_power = (U(p2 % U(2)) != U(0));
- if (has_binary_power)
- {
- // Multiply the result with each binary power contained in the exponent.
- eval_multiply(result, x);
- }
- }
- }
- template <typename T, typename U>
- inline void pow_imp(T& result, const T& t, const U& p, const std::integral_constant<bool, true>&)
- {
- // Signed integer power, just take care of the sign then call the unsigned version:
- using int_type = typename boost::multiprecision::detail::canonical<U, T>::type;
- using ui_type = typename boost::multiprecision::detail::make_unsigned<U>::type ;
- if (p < 0)
- {
- T temp;
- temp = static_cast<int_type>(1);
- T denom;
- pow_imp(denom, t, static_cast<ui_type>(-p), std::integral_constant<bool, false>());
- eval_divide(result, temp, denom);
- return;
- }
- pow_imp(result, t, static_cast<ui_type>(p), std::integral_constant<bool, false>());
- }
- } // namespace detail
- template <typename T, typename U>
- inline typename std::enable_if<boost::multiprecision::detail::is_integral<U>::value>::type eval_pow(T& result, const T& t, const U& p)
- {
- detail::pow_imp(result, t, p, boost::multiprecision::detail::is_signed<U>());
- }
- template <class T>
- void hyp0F0(T& H0F0, const T& x)
- {
- // Compute the series representation of Hypergeometric0F0 taken from
- // http://functions.wolfram.com/HypergeometricFunctions/Hypergeometric0F0/06/01/
- // There are no checks on input range or parameter boundaries.
- using ui_type = typename std::tuple_element<0, typename T::unsigned_types>::type;
- BOOST_ASSERT(&H0F0 != &x);
- long tol = boost::multiprecision::detail::digits2<number<T, et_on> >::value();
- T t;
- T x_pow_n_div_n_fact(x);
- eval_add(H0F0, x_pow_n_div_n_fact, ui_type(1));
- T lim;
- eval_ldexp(lim, H0F0, 1 - tol);
- if (eval_get_sign(lim) < 0)
- lim.negate();
- ui_type n;
- const unsigned series_limit =
- boost::multiprecision::detail::digits2<number<T, et_on> >::value() < 100
- ? 100
- : boost::multiprecision::detail::digits2<number<T, et_on> >::value();
- // Series expansion of hyperg_0f0(; ; x).
- for (n = 2; n < series_limit; ++n)
- {
- eval_multiply(x_pow_n_div_n_fact, x);
- eval_divide(x_pow_n_div_n_fact, n);
- eval_add(H0F0, x_pow_n_div_n_fact);
- bool neg = eval_get_sign(x_pow_n_div_n_fact) < 0;
- if (neg)
- x_pow_n_div_n_fact.negate();
- if (lim.compare(x_pow_n_div_n_fact) > 0)
- break;
- if (neg)
- x_pow_n_div_n_fact.negate();
- }
- if (n >= series_limit)
- BOOST_THROW_EXCEPTION(std::runtime_error("H0F0 failed to converge"));
- }
- template <class T>
- void hyp1F0(T& H1F0, const T& a, const T& x)
- {
- // Compute the series representation of Hypergeometric1F0 taken from
- // http://functions.wolfram.com/HypergeometricFunctions/Hypergeometric1F0/06/01/01/
- // and also see the corresponding section for the power function (i.e. x^a).
- // There are no checks on input range or parameter boundaries.
- using si_type = typename boost::multiprecision::detail::canonical<int, T>::type;
- BOOST_ASSERT(&H1F0 != &x);
- BOOST_ASSERT(&H1F0 != &a);
- T x_pow_n_div_n_fact(x);
- T pochham_a(a);
- T ap(a);
- eval_multiply(H1F0, pochham_a, x_pow_n_div_n_fact);
- eval_add(H1F0, si_type(1));
- T lim;
- eval_ldexp(lim, H1F0, 1 - boost::multiprecision::detail::digits2<number<T, et_on> >::value());
- if (eval_get_sign(lim) < 0)
- lim.negate();
- si_type n;
- T term, part;
- const si_type series_limit =
- boost::multiprecision::detail::digits2<number<T, et_on> >::value() < 100
- ? 100
- : boost::multiprecision::detail::digits2<number<T, et_on> >::value();
- // Series expansion of hyperg_1f0(a; ; x).
- for (n = 2; n < series_limit; n++)
- {
- eval_multiply(x_pow_n_div_n_fact, x);
- eval_divide(x_pow_n_div_n_fact, n);
- eval_increment(ap);
- eval_multiply(pochham_a, ap);
- eval_multiply(term, pochham_a, x_pow_n_div_n_fact);
- eval_add(H1F0, term);
- if (eval_get_sign(term) < 0)
- term.negate();
- if (lim.compare(term) >= 0)
- break;
- }
- if (n >= series_limit)
- BOOST_THROW_EXCEPTION(std::runtime_error("H1F0 failed to converge"));
- }
- template <class T>
- void eval_exp(T& result, const T& x)
- {
- static_assert(number_category<T>::value == number_kind_floating_point, "The exp function is only valid for floating point types.");
- if (&x == &result)
- {
- T temp;
- eval_exp(temp, x);
- result = temp;
- return;
- }
- using ui_type = typename boost::multiprecision::detail::canonical<unsigned, T>::type;
- using si_type = typename boost::multiprecision::detail::canonical<int, T>::type ;
- using exp_type = typename T::exponent_type ;
- using canonical_exp_type = typename boost::multiprecision::detail::canonical<exp_type, T>::type;
- // Handle special arguments.
- int type = eval_fpclassify(x);
- bool isneg = eval_get_sign(x) < 0;
- if (type == (int)FP_NAN)
- {
- result = x;
- errno = EDOM;
- return;
- }
- else if (type == (int)FP_INFINITE)
- {
- if (isneg)
- result = ui_type(0u);
- else
- result = x;
- return;
- }
- else if (type == (int)FP_ZERO)
- {
- result = ui_type(1);
- return;
- }
- // Get local copy of argument and force it to be positive.
- T xx = x;
- T exp_series;
- if (isneg)
- xx.negate();
- // Check the range of the argument.
- if (xx.compare(si_type(1)) <= 0)
- {
- //
- // Use series for exp(x) - 1:
- //
- T lim;
- BOOST_IF_CONSTEXPR(std::numeric_limits<number<T, et_on> >::is_specialized)
- lim = std::numeric_limits<number<T, et_on> >::epsilon().backend();
- else
- {
- result = ui_type(1);
- eval_ldexp(lim, result, 1 - boost::multiprecision::detail::digits2<number<T, et_on> >::value());
- }
- unsigned k = 2;
- exp_series = xx;
- result = si_type(1);
- if (isneg)
- eval_subtract(result, exp_series);
- else
- eval_add(result, exp_series);
- eval_multiply(exp_series, xx);
- eval_divide(exp_series, ui_type(k));
- eval_add(result, exp_series);
- while (exp_series.compare(lim) > 0)
- {
- ++k;
- eval_multiply(exp_series, xx);
- eval_divide(exp_series, ui_type(k));
- if (isneg && (k & 1))
- eval_subtract(result, exp_series);
- else
- eval_add(result, exp_series);
- }
- return;
- }
- // Check for pure-integer arguments which can be either signed or unsigned.
- typename boost::multiprecision::detail::canonical<std::intmax_t, T>::type ll;
- eval_trunc(exp_series, x);
- eval_convert_to(&ll, exp_series);
- if (x.compare(ll) == 0)
- {
- detail::pow_imp(result, get_constant_e<T>(), ll, std::integral_constant<bool, true>());
- return;
- }
- else if (exp_series.compare(x) == 0)
- {
- // We have a value that has no fractional part, but is too large to fit
- // in a long long, in this situation the code below will fail, so
- // we're just going to assume that this will overflow:
- if (isneg)
- result = ui_type(0);
- else
- result = std::numeric_limits<number<T> >::has_infinity ? std::numeric_limits<number<T> >::infinity().backend() : (std::numeric_limits<number<T> >::max)().backend();
- return;
- }
- // The algorithm for exp has been taken from MPFUN.
- // exp(t) = [ (1 + r + r^2/2! + r^3/3! + r^4/4! ...)^p2 ] * 2^n
- // where p2 is a power of 2 such as 2048, r = t_prime / p2, and
- // t_prime = t - n*ln2, with n chosen to minimize the absolute
- // value of t_prime. In the resulting Taylor series, which is
- // implemented as a hypergeometric function, |r| is bounded by
- // ln2 / p2. For small arguments, no scaling is done.
- // Compute the exponential series of the (possibly) scaled argument.
- eval_divide(result, xx, get_constant_ln2<T>());
- exp_type n;
- eval_convert_to(&n, result);
- if (n == (std::numeric_limits<exp_type>::max)())
- {
- // Exponent is too large to fit in our exponent type:
- if (isneg)
- result = ui_type(0);
- else
- result = std::numeric_limits<number<T> >::has_infinity ? std::numeric_limits<number<T> >::infinity().backend() : (std::numeric_limits<number<T> >::max)().backend();
- return;
- }
- // The scaling is 2^11 = 2048.
- const si_type p2 = static_cast<si_type>(si_type(1) << 11);
- eval_multiply(exp_series, get_constant_ln2<T>(), static_cast<canonical_exp_type>(n));
- eval_subtract(exp_series, xx);
- eval_divide(exp_series, p2);
- exp_series.negate();
- hyp0F0(result, exp_series);
- detail::pow_imp(exp_series, result, p2, std::integral_constant<bool, true>());
- result = ui_type(1);
- eval_ldexp(result, result, n);
- eval_multiply(exp_series, result);
- if (isneg)
- eval_divide(result, ui_type(1), exp_series);
- else
- result = exp_series;
- }
- template <class T>
- void eval_log(T& result, const T& arg)
- {
- static_assert(number_category<T>::value == number_kind_floating_point, "The log function is only valid for floating point types.");
- //
- // We use a variation of http://dlmf.nist.gov/4.45#i
- // using frexp to reduce the argument to x * 2^n,
- // then let y = x - 1 and compute:
- // log(x) = log(2) * n + log1p(1 + y)
- //
- using ui_type = typename boost::multiprecision::detail::canonical<unsigned, T>::type;
- using exp_type = typename T::exponent_type ;
- using canonical_exp_type = typename boost::multiprecision::detail::canonical<exp_type, T>::type;
- using fp_type = typename std::tuple_element<0, typename T::float_types>::type ;
- int s = eval_signbit(arg);
- switch (eval_fpclassify(arg))
- {
- case FP_NAN:
- result = arg;
- errno = EDOM;
- return;
- case FP_INFINITE:
- if (s)
- break;
- result = arg;
- return;
- case FP_ZERO:
- result = std::numeric_limits<number<T> >::has_infinity ? std::numeric_limits<number<T> >::infinity().backend() : (std::numeric_limits<number<T> >::max)().backend();
- result.negate();
- errno = ERANGE;
- return;
- }
- if (s)
- {
- result = std::numeric_limits<number<T> >::quiet_NaN().backend();
- errno = EDOM;
- return;
- }
- exp_type e;
- T t;
- eval_frexp(t, arg, &e);
- bool alternate = false;
- if (t.compare(fp_type(2) / fp_type(3)) <= 0)
- {
- alternate = true;
- eval_ldexp(t, t, 1);
- --e;
- }
- eval_multiply(result, get_constant_ln2<T>(), canonical_exp_type(e));
- INSTRUMENT_BACKEND(result);
- eval_subtract(t, ui_type(1)); /* -0.3 <= t <= 0.3 */
- if (!alternate)
- t.negate(); /* 0 <= t <= 0.33333 */
- T pow = t;
- T lim;
- T t2;
- if (alternate)
- eval_add(result, t);
- else
- eval_subtract(result, t);
- BOOST_IF_CONSTEXPR(std::numeric_limits<number<T, et_on> >::is_specialized)
- eval_multiply(lim, result, std::numeric_limits<number<T, et_on> >::epsilon().backend());
- else
- eval_ldexp(lim, result, 1 - boost::multiprecision::detail::digits2<number<T, et_on> >::value());
- if (eval_get_sign(lim) < 0)
- lim.negate();
- INSTRUMENT_BACKEND(lim);
- ui_type k = 1;
- do
- {
- ++k;
- eval_multiply(pow, t);
- eval_divide(t2, pow, k);
- INSTRUMENT_BACKEND(t2);
- if (alternate && ((k & 1) != 0))
- eval_add(result, t2);
- else
- eval_subtract(result, t2);
- INSTRUMENT_BACKEND(result);
- } while (lim.compare(t2) < 0);
- }
- template <class T>
- const T& get_constant_log10()
- {
- static BOOST_MP_THREAD_LOCAL T result;
- static BOOST_MP_THREAD_LOCAL long digits = 0;
- if ((digits != boost::multiprecision::detail::digits2<number<T> >::value()))
- {
- using ui_type = typename boost::multiprecision::detail::canonical<unsigned, T>::type;
- T ten;
- ten = ui_type(10u);
- eval_log(result, ten);
- digits = boost::multiprecision::detail::digits2<number<T> >::value();
- }
- return result;
- }
- template <class T>
- void eval_log10(T& result, const T& arg)
- {
- static_assert(number_category<T>::value == number_kind_floating_point, "The log10 function is only valid for floating point types.");
- eval_log(result, arg);
- eval_divide(result, get_constant_log10<T>());
- }
- template <class R, class T>
- inline void eval_log2(R& result, const T& a)
- {
- eval_log(result, a);
- eval_divide(result, get_constant_ln2<R>());
- }
- template <typename T>
- inline void eval_pow(T& result, const T& x, const T& a)
- {
- static_assert(number_category<T>::value == number_kind_floating_point, "The pow function is only valid for floating point types.");
- using si_type = typename boost::multiprecision::detail::canonical<int, T>::type;
- using fp_type = typename std::tuple_element<0, typename T::float_types>::type ;
- if ((&result == &x) || (&result == &a))
- {
- T t;
- eval_pow(t, x, a);
- result = t;
- return;
- }
- if ((a.compare(si_type(1)) == 0) || (x.compare(si_type(1)) == 0))
- {
- result = x;
- return;
- }
- if (a.compare(si_type(0)) == 0)
- {
- result = si_type(1);
- return;
- }
- int type = eval_fpclassify(x);
- switch (type)
- {
- case FP_ZERO:
- switch (eval_fpclassify(a))
- {
- case FP_ZERO:
- result = si_type(1);
- break;
- case FP_NAN:
- result = a;
- break;
- case FP_NORMAL: {
- // Need to check for a an odd integer as a special case:
- BOOST_TRY
- {
- typename boost::multiprecision::detail::canonical<std::intmax_t, T>::type i;
- eval_convert_to(&i, a);
- if (a.compare(i) == 0)
- {
- if (eval_signbit(a))
- {
- if (i & 1)
- {
- result = std::numeric_limits<number<T> >::infinity().backend();
- if (eval_signbit(x))
- result.negate();
- errno = ERANGE;
- }
- else
- {
- result = std::numeric_limits<number<T> >::infinity().backend();
- errno = ERANGE;
- }
- }
- else if (i & 1)
- {
- result = x;
- }
- else
- result = si_type(0);
- return;
- }
- }
- BOOST_CATCH(const std::exception&)
- {
- // fallthrough..
- }
- BOOST_CATCH_END
- BOOST_FALLTHROUGH;
- }
- default:
- if (eval_signbit(a))
- {
- result = std::numeric_limits<number<T> >::infinity().backend();
- errno = ERANGE;
- }
- else
- result = x;
- break;
- }
- return;
- case FP_NAN:
- result = x;
- errno = ERANGE;
- return;
- default:;
- }
- int s = eval_get_sign(a);
- if (s == 0)
- {
- result = si_type(1);
- return;
- }
- if (s < 0)
- {
- T t, da;
- t = a;
- t.negate();
- eval_pow(da, x, t);
- eval_divide(result, si_type(1), da);
- return;
- }
- typename boost::multiprecision::detail::canonical<std::intmax_t, T>::type an;
- typename boost::multiprecision::detail::canonical<std::intmax_t, T>::type max_an =
- std::numeric_limits<typename boost::multiprecision::detail::canonical<std::intmax_t, T>::type>::is_specialized ? (std::numeric_limits<typename boost::multiprecision::detail::canonical<std::intmax_t, T>::type>::max)() : static_cast<typename boost::multiprecision::detail::canonical<std::intmax_t, T>::type>(1) << (sizeof(typename boost::multiprecision::detail::canonical<std::intmax_t, T>::type) * CHAR_BIT - 2);
- typename boost::multiprecision::detail::canonical<std::intmax_t, T>::type min_an =
- std::numeric_limits<typename boost::multiprecision::detail::canonical<std::intmax_t, T>::type>::is_specialized ? (std::numeric_limits<typename boost::multiprecision::detail::canonical<std::intmax_t, T>::type>::min)() : -min_an;
- T fa;
- BOOST_TRY
- {
- eval_convert_to(&an, a);
- if (a.compare(an) == 0)
- {
- detail::pow_imp(result, x, an, std::integral_constant<bool, true>());
- return;
- }
- }
- BOOST_CATCH(const std::exception&)
- {
- // conversion failed, just fall through, value is not an integer.
- an = (std::numeric_limits<std::intmax_t>::max)();
- }
- BOOST_CATCH_END
- if ((eval_get_sign(x) < 0))
- {
- typename boost::multiprecision::detail::canonical<std::uintmax_t, T>::type aun;
- BOOST_TRY
- {
- eval_convert_to(&aun, a);
- if (a.compare(aun) == 0)
- {
- fa = x;
- fa.negate();
- eval_pow(result, fa, a);
- if (aun & 1u)
- result.negate();
- return;
- }
- }
- BOOST_CATCH(const std::exception&)
- {
- // conversion failed, just fall through, value is not an integer.
- }
- BOOST_CATCH_END
- eval_floor(result, a);
- // -1^INF is a special case in C99:
- if ((x.compare(si_type(-1)) == 0) && (eval_fpclassify(a) == FP_INFINITE))
- {
- result = si_type(1);
- }
- else if (a.compare(result) == 0)
- {
- // exponent is so large we have no fractional part:
- if (x.compare(si_type(-1)) < 0)
- {
- result = std::numeric_limits<number<T, et_on> >::infinity().backend();
- }
- else
- {
- result = si_type(0);
- }
- }
- else if (type == FP_INFINITE)
- {
- result = std::numeric_limits<number<T, et_on> >::infinity().backend();
- }
- else BOOST_IF_CONSTEXPR (std::numeric_limits<number<T, et_on> >::has_quiet_NaN)
- {
- result = std::numeric_limits<number<T, et_on> >::quiet_NaN().backend();
- errno = EDOM;
- }
- else
- {
- BOOST_THROW_EXCEPTION(std::domain_error("Result of pow is undefined or non-real and there is no NaN for this number type."));
- }
- return;
- }
- T t, da;
- eval_subtract(da, a, an);
- if ((x.compare(fp_type(0.5)) >= 0) && (x.compare(fp_type(0.9)) < 0) && (an < max_an) && (an > min_an))
- {
- if (a.compare(fp_type(1e-5f)) <= 0)
- {
- // Series expansion for small a.
- eval_log(t, x);
- eval_multiply(t, a);
- hyp0F0(result, t);
- return;
- }
- else
- {
- // Series expansion for moderately sized x. Note that for large power of a,
- // the power of the integer part of a is calculated using the pown function.
- if (an)
- {
- da.negate();
- t = si_type(1);
- eval_subtract(t, x);
- hyp1F0(result, da, t);
- detail::pow_imp(t, x, an, std::integral_constant<bool, true>());
- eval_multiply(result, t);
- }
- else
- {
- da = a;
- da.negate();
- t = si_type(1);
- eval_subtract(t, x);
- hyp1F0(result, da, t);
- }
- }
- }
- else
- {
- // Series expansion for pow(x, a). Note that for large power of a, the power
- // of the integer part of a is calculated using the pown function.
- if (an)
- {
- eval_log(t, x);
- eval_multiply(t, da);
- eval_exp(result, t);
- detail::pow_imp(t, x, an, std::integral_constant<bool, true>());
- eval_multiply(result, t);
- }
- else
- {
- eval_log(t, x);
- eval_multiply(t, a);
- eval_exp(result, t);
- }
- }
- }
- template <class T, class A>
- #if BOOST_WORKAROUND(BOOST_MSVC, < 1800)
- inline typename std::enable_if<!boost::multiprecision::detail::is_integral<A>::value, void>::type
- #else
- inline typename std::enable_if<is_compatible_arithmetic_type<A, number<T> >::value && !boost::multiprecision::detail::is_integral<A>::value, void>::type
- #endif
- eval_pow(T& result, const T& x, const A& a)
- {
- // Note this one is restricted to float arguments since pow.hpp already has a version for
- // integer powers....
- using canonical_type = typename boost::multiprecision::detail::canonical<A, T>::type ;
- using cast_type = typename std::conditional<std::is_same<A, canonical_type>::value, T, canonical_type>::type;
- cast_type c;
- c = a;
- eval_pow(result, x, c);
- }
- template <class T, class A>
- #if BOOST_WORKAROUND(BOOST_MSVC, < 1800)
- inline void
- #else
- inline typename std::enable_if<is_compatible_arithmetic_type<A, number<T> >::value, void>::type
- #endif
- eval_pow(T& result, const A& x, const T& a)
- {
- using canonical_type = typename boost::multiprecision::detail::canonical<A, T>::type ;
- using cast_type = typename std::conditional<std::is_same<A, canonical_type>::value, T, canonical_type>::type;
- cast_type c;
- c = x;
- eval_pow(result, c, a);
- }
- template <class T>
- void eval_exp2(T& result, const T& arg)
- {
- static_assert(number_category<T>::value == number_kind_floating_point, "The log function is only valid for floating point types.");
- // Check for pure-integer arguments which can be either signed or unsigned.
- typename boost::multiprecision::detail::canonical<typename T::exponent_type, T>::type i;
- T temp;
- BOOST_TRY
- {
- eval_trunc(temp, arg);
- eval_convert_to(&i, temp);
- if (arg.compare(i) == 0)
- {
- temp = static_cast<typename std::tuple_element<0, typename T::unsigned_types>::type>(1u);
- eval_ldexp(result, temp, i);
- return;
- }
- }
- BOOST_CATCH(const boost::math::rounding_error&)
- { /* Fallthrough */
- }
- BOOST_CATCH(const std::runtime_error&)
- { /* Fallthrough */
- }
- BOOST_CATCH_END
- temp = static_cast<typename std::tuple_element<0, typename T::unsigned_types>::type>(2u);
- eval_pow(result, temp, arg);
- }
- namespace detail {
- template <class T>
- void small_sinh_series(T x, T& result)
- {
- using ui_type = typename boost::multiprecision::detail::canonical<unsigned, T>::type;
- bool neg = eval_get_sign(x) < 0;
- if (neg)
- x.negate();
- T p(x);
- T mult(x);
- eval_multiply(mult, x);
- result = x;
- ui_type k = 1;
- T lim(x);
- eval_ldexp(lim, lim, 1 - boost::multiprecision::detail::digits2<number<T, et_on> >::value());
- do
- {
- eval_multiply(p, mult);
- eval_divide(p, ++k);
- eval_divide(p, ++k);
- eval_add(result, p);
- } while (p.compare(lim) >= 0);
- if (neg)
- result.negate();
- }
- template <class T>
- void sinhcosh(const T& x, T* p_sinh, T* p_cosh)
- {
- using ui_type = typename boost::multiprecision::detail::canonical<unsigned, T>::type;
- using fp_type = typename std::tuple_element<0, typename T::float_types>::type ;
- switch (eval_fpclassify(x))
- {
- case FP_NAN:
- errno = EDOM;
- // fallthrough...
- case FP_INFINITE:
- if (p_sinh)
- *p_sinh = x;
- if (p_cosh)
- {
- *p_cosh = x;
- if (eval_get_sign(x) < 0)
- p_cosh->negate();
- }
- return;
- case FP_ZERO:
- if (p_sinh)
- *p_sinh = x;
- if (p_cosh)
- *p_cosh = ui_type(1);
- return;
- default:;
- }
- bool small_sinh = eval_get_sign(x) < 0 ? x.compare(fp_type(-0.5)) > 0 : x.compare(fp_type(0.5)) < 0;
- if (p_cosh || !small_sinh)
- {
- T e_px, e_mx;
- eval_exp(e_px, x);
- eval_divide(e_mx, ui_type(1), e_px);
- if (eval_signbit(e_mx) != eval_signbit(e_px))
- e_mx.negate(); // Handles lack of signed zero in some types
- if (p_sinh)
- {
- if (small_sinh)
- {
- small_sinh_series(x, *p_sinh);
- }
- else
- {
- eval_subtract(*p_sinh, e_px, e_mx);
- eval_ldexp(*p_sinh, *p_sinh, -1);
- }
- }
- if (p_cosh)
- {
- eval_add(*p_cosh, e_px, e_mx);
- eval_ldexp(*p_cosh, *p_cosh, -1);
- }
- }
- else
- {
- small_sinh_series(x, *p_sinh);
- }
- }
- } // namespace detail
- template <class T>
- inline void eval_sinh(T& result, const T& x)
- {
- static_assert(number_category<T>::value == number_kind_floating_point, "The sinh function is only valid for floating point types.");
- detail::sinhcosh(x, &result, static_cast<T*>(0));
- }
- template <class T>
- inline void eval_cosh(T& result, const T& x)
- {
- static_assert(number_category<T>::value == number_kind_floating_point, "The cosh function is only valid for floating point types.");
- detail::sinhcosh(x, static_cast<T*>(0), &result);
- }
- template <class T>
- inline void eval_tanh(T& result, const T& x)
- {
- static_assert(number_category<T>::value == number_kind_floating_point, "The tanh function is only valid for floating point types.");
- T c;
- detail::sinhcosh(x, &result, &c);
- if ((eval_fpclassify(result) == FP_INFINITE) && (eval_fpclassify(c) == FP_INFINITE))
- {
- bool s = eval_signbit(result) != eval_signbit(c);
- result = static_cast<typename std::tuple_element<0, typename T::unsigned_types>::type>(1u);
- if (s)
- result.negate();
- return;
- }
- eval_divide(result, c);
- }
- #ifdef BOOST_MSVC
- #pragma warning(pop)
- #endif
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