Sprout/sprout/math/fdim.hpp
bolero-MURAKAMI 6ccd6e1cf4 add sprout::cbrt, hypot, fmax, fmin, fdim
fix sprout::pow case x==0
2012-05-05 18:50:17 +09:00

48 lines
1.4 KiB
C++

#ifndef SPROUT_MATH_FDIM_HPP
#define SPROUT_MATH_FDIM_HPP
#include <type_traits>
#include <sprout/config.hpp>
#include <sprout/math/float_promote.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
fdim(FloatType x, FloatType y) {
return x > y ? x - y : 0;
}
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::math::float_promote<ArithmeticType1, ArithmeticType2>::type
fdim(ArithmeticType1 x, ArithmeticType2 y) {
typedef typename sprout::math::float_promote<ArithmeticType1, ArithmeticType2>::type type;
return sprout::math::detail::fdim(static_cast<type>(x), static_cast<type>(y));
}
} // namespace detail
# if SPROUT_USE_BUILTIN_CMATH_FUNCTION
using std::fdim;
# else
using sprout::math::detail::fdim;
# endif
} // namespace math
using sprout::math::fdim;
} // namespace sprout
#endif // #ifndef SPROUT_MATH_FDIM_HPP