Sprout/sprout/math/hypot.hpp
2013-02-14 18:02:43 +09:00

52 lines
1.8 KiB
C++

#ifndef SPROUT_MATH_HYPOT_HPP
#define SPROUT_MATH_HYPOT_HPP
#include <limits>
#include <type_traits>
#include <sprout/config.hpp>
#include <sprout/type_traits/float_promote.hpp>
#include <sprout/type_traits/enabler_if.hpp>
#include <sprout/math/detail/config.hpp>
#include <sprout/math/fabs.hpp>
#include <sprout/math/sqrt.hpp>
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
hypot(FloatType x, FloatType y) {
return y == 0 ? sprout::math::fabs(x)
: x == 0 ? sprout::math::fabs(y)
: y == std::numeric_limits<FloatType>::infinity() || y == -std::numeric_limits<FloatType>::infinity()
? std::numeric_limits<FloatType>::infinity()
: x == std::numeric_limits<FloatType>::infinity() || x == -std::numeric_limits<FloatType>::infinity()
? std::numeric_limits<FloatType>::infinity()
: sprout::math::sqrt(x * x + y * y)
;
}
template<
typename ArithmeticType1,
typename ArithmeticType2,
typename sprout::enabler_if<
std::is_arithmetic<ArithmeticType1>::value && std::is_arithmetic<ArithmeticType2>::value
>::type = sprout::enabler
>
inline SPROUT_CONSTEXPR typename sprout::float_promote<ArithmeticType1, ArithmeticType2>::type
hypot(ArithmeticType1 x, ArithmeticType2 y) {
typedef typename sprout::float_promote<ArithmeticType1, ArithmeticType2>::type type;
return sprout::math::detail::hypot(static_cast<type>(x), static_cast<type>(y));
}
} // namespace detail
using NS_SPROUT_MATH_DETAIL::hypot;
} // namespace math
using sprout::math::hypot;
} // namespace sprout
#endif // #ifndef SPROUT_MATH_HYPOT_HPP