Sprout/sprout/math/float_significand.hpp
2019-01-07 17:47:17 +09:00

51 lines
1.8 KiB
C++

/*=============================================================================
Copyright (c) 2011-2019 Bolero MURAKAMI
https://github.com/bolero-MURAKAMI/Sprout
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
=============================================================================*/
#ifndef SPROUT_MATH_FLOAT_SIGNIFICAND_HPP
#define SPROUT_MATH_FLOAT_SIGNIFICAND_HPP
#include <type_traits>
#include <sprout/config.hpp>
#include <sprout/limits.hpp>
#include <sprout/detail/pow.hpp>
#include <sprout/math/detail/config.hpp>
#include <sprout/math/isnan.hpp>
#include <sprout/math/float_exponent.hpp>
#include <sprout/type_traits/enabler_if.hpp>
namespace sprout {
namespace math {
//
// float_significand
//
template<
typename FloatType,
typename sprout::enabler_if<std::is_floating_point<FloatType>::value>::type = sprout::enabler
>
inline SPROUT_CONSTEXPR FloatType
float_significand(FloatType x) {
return sprout::math::isnan(x) ? x
: x == sprout::numeric_limits<FloatType>::infinity() ? sprout::numeric_limits<FloatType>::infinity()
: x == -sprout::numeric_limits<FloatType>::infinity() ? -sprout::numeric_limits<FloatType>::infinity()
: x == 0 ? x
: x / sprout::detail::pow_n(FloatType(sprout::numeric_limits<FloatType>::radix), sprout::float_exponent(x))
;
}
template<
typename IntType,
typename sprout::enabler_if<std::is_integral<IntType>::value>::type = sprout::enabler
>
inline SPROUT_CONSTEXPR double
float_significand(IntType x) {
return sprout::math::float_significand(static_cast<double>(x));
}
} // namespace math
using sprout::math::float_significand;
} // namespace sprout
#endif // #ifndef SPROUT_MATH_FLOAT_SIGNIFICAND_HPP