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add math::copysign

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fix hyperbolic and exponental functions: for special values
This commit is contained in:
bolero-MURAKAMI 2013-04-24 22:48:36 +09:00
parent a27c83e939
commit 32c3ba02d4
50 changed files with 540 additions and 216 deletions
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33
sprout/math/exp.hpp
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@ -10,6 +10,7 @@
#include <sprout/math/detail/float_compute.hpp>
#include <sprout/math/factorial.hpp>
#include <sprout/type_traits/enabler_if.hpp>
#include <sprout/type_traits/float_promote.hpp>
namespace sprout {
namespace math {
@ -18,7 +19,7 @@ namespace sprout {
inline SPROUT_CONSTEXPR T
exp_impl_1(T x, std::size_t n, std::size_t last) {
return last - n == 1
? sprout::detail::pow_n(x, n) / sprout::math::factorial<T>(n)
? sprout::detail::pow_n(x, n) / sprout::math::unchecked_factorial<T>(n)
: sprout::math::detail::exp_impl_1(x, n, n + (last - n) / 2)
+ sprout::math::detail::exp_impl_1(x, n + (last - n) / 2, last)
;
@ -26,7 +27,9 @@ namespace sprout {
template<typename T>
inline SPROUT_CONSTEXPR T
exp_impl(T x) {
return T(1) + sprout::math::detail::exp_impl_1(x, 1, sprout::math::factorial_limit<T>() / 2 + 1);
return !(x > -1) ? T(1) / (T(1) + sprout::math::detail::exp_impl_1(-x, 1, sprout::math::factorial_limit<T>() / 2 + 1))
: T(1) + sprout::math::detail::exp_impl_1(x, 1, sprout::math::factorial_limit<T>() / 2 + 1)
;
}
template<
@ -35,15 +38,16 @@ namespace sprout {
>
inline SPROUT_CONSTEXPR FloatType
exp(FloatType x) {
typedef typename sprout::math::detail::float_compute<FloatType>::type type;
return x == 0 ? FloatType(1)
: x == -std::numeric_limits<FloatType>::infinity() ? FloatType(0)
return x == -std::numeric_limits<FloatType>::infinity() ? FloatType(0)
: x == std::numeric_limits<FloatType>::infinity() ? std::numeric_limits<FloatType>::infinity()
: !(x > -1) ? static_cast<FloatType>(type(1) / sprout::math::detail::exp_impl(-static_cast<type>(x)))
: static_cast<FloatType>(sprout::math::detail::exp_impl(static_cast<type>(x)))
#if SPROUT_USE_BUILTIN_CMATH_FUNCTION
: std::exp(x)
#else
: x == 0 ? FloatType(1)
: static_cast<FloatType>(sprout::math::detail::exp_impl(static_cast<typename sprout::math::detail::float_compute<FloatType>::type>(x)))
#endif
;
}
template<
typename IntType,
typename sprout::enabler_if<std::is_integral<IntType>::value>::type = sprout::enabler
@ -53,8 +57,17 @@ namespace sprout {
return sprout::math::detail::exp(static_cast<double>(x));
}
} // namespace detail
using NS_SPROUT_MATH_DETAIL::exp;
//
// exp
//
template<
typename ArithmeticType,
typename sprout::enabler_if<std::is_arithmetic<ArithmeticType>::value>::type = sprout::enabler
>
inline SPROUT_CONSTEXPR typename sprout::float_promote<ArithmeticType>::type
exp(ArithmeticType x) {
return sprout::math::detail::exp(x);
}
} // namespace math
using sprout::math::exp;