Sprout/sprout/math/scalbln.hpp

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#ifndef SPROUT_MATH_SCALBLN_HPP
#define SPROUT_MATH_SCALBLN_HPP
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#include <limits>
#include <type_traits>
#include <sprout/config.hpp>
#include <sprout/math/detail/config.hpp>
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#include <sprout/math/detail/float_compute.hpp>
#include <sprout/math/copysign.hpp>
#include <sprout/detail/pow.hpp>
#include <sprout/type_traits/enabler_if.hpp>
namespace sprout {
namespace math {
namespace detail {
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template<typename FloatType, typename T>
inline SPROUT_CONSTEXPR T
scalbln_impl(T x, long exp) {
return x * sprout::detail::pow_n(T(std::numeric_limits<FloatType>::radix), exp);
}
template<
typename FloatType,
typename sprout::enabler_if<std::is_floating_point<FloatType>::value>::type = sprout::enabler
>
inline SPROUT_CONSTEXPR FloatType
scalbln(FloatType x, long exp) {
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return x == std::numeric_limits<FloatType>::infinity() ? std::numeric_limits<FloatType>::infinity()
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: x == -std::numeric_limits<FloatType>::infinity() ? -std::numeric_limits<FloatType>::infinity()
: exp == 0 ? x
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: x == 0 ? sprout::math::copysign(FloatType(0), x)
: static_cast<FloatType>(sprout::math::detail::scalbln_impl<FloatType>(static_cast<typename sprout::math::detail::float_compute<FloatType>::type>(x), exp))
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;
}
template<
typename IntType,
typename sprout::enabler_if<std::is_integral<IntType>::value>::type = sprout::enabler
>
inline SPROUT_CONSTEXPR double
scalbln(IntType x, long exp) {
return sprout::math::detail::scalbln(static_cast<double>(x), exp);
}
} // namespace detail
using NS_SPROUT_MATH_DETAIL::scalbln;
} // namespace math
using sprout::math::scalbln;
} // namespace sprout
#endif // #ifndef SPROUT_MATH_SCALBLN_HPP