Sprout/sprout/math/cbrt.hpp
2012-05-10 13:34:49 +09:00

47 lines
1.2 KiB
C++

#ifndef SPROUT_MATH_CBRT_HPP
#define SPROUT_MATH_CBRT_HPP
#include <type_traits>
#include <sprout/config.hpp>
#include <sprout/math/pow.hpp>
#include <sprout/math/constants.hpp>
#include <sprout/utility/enabler_if.hpp>
#if SPROUT_USE_BUILTIN_CMATH_FUNCTION
# include <cmath>
#endif
namespace sprout {
namespace math {
namespace detail {
template<
typename FloatType,
typename sprout::enabler_if<std::is_floating_point<FloatType>::value>::type = sprout::enabler
>
inline SPROUT_CONSTEXPR FloatType
cbrt(FloatType x) {
return x < 0 ? -sprout::math::pow(-x, sprout::math::third<FloatType>())
: sprout::math::pow(x, sprout::math::third<FloatType>())
;
}
template<
typename IntType,
typename sprout::enabler_if<std::is_integral<IntType>::value>::type = sprout::enabler
>
inline SPROUT_CONSTEXPR double
cbrt(IntType x) {
return sprout::math::detail::cbrt(static_cast<double>(x));
}
} // namespace detail
# if SPROUT_USE_BUILTIN_CMATH_FUNCTION
using std::cbrt;
# else
using sprout::math::detail::cbrt;
# endif
} // namespace math
using sprout::math::cbrt;
} // namespace sprout
#endif // #ifndef SPROUT_MATH_CBRT_HPP