Method atanh

extern/half/include/half.hpp:1558–1565

Hyperbolic area tangent implementation. \param arg function argument \return function value stored in single-preicision

			/// \param arg function argument
			/// \return function value stored in single-preicision
			static expr atanh(float arg)
			{
			#if HALF_ENABLE_CPP11_CMATH
				return expr(std::atanh(arg));
			#else
				return expr(static_cast<float>(0.5*std::log((1.0+arg)/(1.0-arg))));
			#endif
			}

			/// Error function implementation.
			/// \param arg function argument