Function ilogb

include/half_float/half.hpp:4247–4257

Extract exponent. See also:** Documentation for [std::ilogb](https://en.cppreference.com/w/cpp/numeric/math/ilogb). \param arg number to query \return floating-point exponent \retval FP_ILOGB0 for zero \retval FP_ILOGBNAN for NaN \retval INT_MAX for infinity \exception FE_INVALID for 0 or infinite values

	/// \retval INT_MAX for infinity
	/// \exception FE_INVALID for 0 or infinite values
	inline int ilogb(half arg)
	{
		int abs = arg.data_ & 0x7FFF, exp;
		if(!abs || abs >= 0x7C00)
		{
			detail::raise(FE_INVALID);
			return !abs ? FP_ILOGB0 : (abs==0x7C00) ? INT_MAX : FP_ILOGBNAN;
		}
		for(exp=(abs>>10)-15; abs<0x200; abs<<=1,--exp) ;
		return exp;
	}

	/// Extract exponent.
	/// **See also:** Documentation for [std::logb](https://en.cppreference.com/w/cpp/numeric/math/logb).