williamr@2: // (C) Copyright John Maddock 2005. williamr@2: // Use, modification and distribution are subject to the williamr@2: // Boost Software License, Version 1.0. (See accompanying file williamr@2: // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) williamr@2: williamr@2: #ifndef BOOST_MATH_COMPLEX_ATAN_INCLUDED williamr@2: #define BOOST_MATH_COMPLEX_ATAN_INCLUDED williamr@2: williamr@2: #ifndef BOOST_MATH_COMPLEX_DETAILS_INCLUDED williamr@2: # include williamr@2: #endif williamr@2: #ifndef BOOST_MATH_COMPLEX_ATANH_INCLUDED williamr@2: # include williamr@2: #endif williamr@2: williamr@2: namespace boost{ namespace math{ williamr@2: williamr@2: template williamr@2: std::complex atan(const std::complex& x) williamr@2: { williamr@2: // williamr@2: // We're using the C99 definition here; atan(z) = -i atanh(iz): williamr@2: // williamr@2: if(x.real() == 0) williamr@2: { williamr@2: if(x.imag() == 1) williamr@2: return std::complex(0, std::numeric_limits::has_infinity ? std::numeric_limits::infinity() : static_cast(HUGE_VAL)); williamr@2: if(x.imag() == -1) williamr@2: return std::complex(0, std::numeric_limits::has_infinity ? -std::numeric_limits::infinity() : -static_cast(HUGE_VAL)); williamr@2: } williamr@2: return ::boost::math::detail::mult_minus_i(::boost::math::atanh(::boost::math::detail::mult_i(x))); williamr@2: } williamr@2: williamr@2: } } // namespaces williamr@2: williamr@2: #endif // BOOST_MATH_COMPLEX_ATAN_INCLUDED