Sprout/sprout/math/remainder.hpp
2013-05-08 01:46:40 +09:00

65 lines
2.3 KiB
C++

#ifndef SPROUT_MATH_REMAINDER_HPP
#define SPROUT_MATH_REMAINDER_HPP
#include <limits>
#include <type_traits>
#include <sprout/config.hpp>
#include <sprout/math/detail/config.hpp>
#include <sprout/math/isnan.hpp>
#include <sprout/math/signbit.hpp>
#include <sprout/math/rem_quo.hpp>
#include <sprout/type_traits/enabler_if.hpp>
#include <sprout/type_traits/float_promote.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
remainder(FloatType x, FloatType y) {
return y == 0 ? -std::numeric_limits<FloatType>::quiet_NaN()
: sprout::math::isnan(y)
? sprout::math::isnan(x)
? sprout::math::signbit(y) && sprout::math::signbit(x) ? -std::numeric_limits<FloatType>::quiet_NaN()
: std::numeric_limits<FloatType>::quiet_NaN()
: y
: sprout::math::isnan(x) ? x
: x == std::numeric_limits<FloatType>::infinity() || x == -std::numeric_limits<FloatType>::infinity()
? -std::numeric_limits<FloatType>::quiet_NaN()
: x == 0 ? x
: y == std::numeric_limits<FloatType>::infinity() || y == -std::numeric_limits<FloatType>::infinity() ? x
#if SPROUT_USE_BUILTIN_CMATH_FUNCTION
: std::remainder(x, y)
#else
: sprout::math::rem_quo(x, y).first
#endif
;
}
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
remainder(ArithmeticType1 x, ArithmeticType2 y) {
typedef typename sprout::float_promote<ArithmeticType1, ArithmeticType2>::type type;
return sprout::math::detail::remainder(static_cast<type>(x), static_cast<type>(y));
}
} // namespace detail
//
// issue:
// remainder(-NaN, -NaN) returns -NaN .
// # returns +NaN . ( same as remainder(+NaN, +NaN) )
//
using sprout::math::detail::remainder;
} // namespace math
using sprout::math::remainder;
} // namespace sprout
#endif // #ifndef SPROUT_MATH_REMAINDER_HPP