// (C) Copyright John Maddock 2005-2006. // Use, modification and distribution are subject to 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 BOOST_MATH_HYPOT_INCLUDED #define BOOST_MATH_HYPOT_INCLUDED #ifdef _MSC_VER #pragma once #endif #include <boost/math/tools/config.hpp> #include <boost/math/tools/precision.hpp> #include <boost/math/policies/error_handling.hpp> #include <boost/math/special_functions/math_fwd.hpp> #include <boost/config/no_tr1/cmath.hpp> #include <algorithm> // for swap #ifdef BOOST_NO_STDC_NAMESPACE namespace std{ using ::sqrt; using ::fabs; } #endif namespace boost{ namespace math{ namespace detail{ template <class T, class Policy> T hypot_imp(T x, T y, const Policy& pol) { // // Normalize x and y, so that both are positive and x >= y: // using std::fabs; using std::sqrt; // ADL of std names x = fabs(x); y = fabs(y); #ifdef BOOST_MSVC #pragma warning(push) #pragma warning(disable: 4127) #endif // special case, see C99 Annex F: if(std::numeric_limits<T>::has_infinity && ((x == std::numeric_limits<T>::infinity()) || (y == std::numeric_limits<T>::infinity()))) return policies::raise_overflow_error<T>("boost::math::hypot<%1%>(%1%,%1%)", 0, pol); #ifdef BOOST_MSVC #pragma warning(pop) #endif if(y > x) (std::swap)(x, y); if(x * tools::epsilon<T>() >= y) return x; T rat = y / x; return x * sqrt(1 + rat*rat); } // template <class T> T hypot(T x, T y) } template <class T1, class T2> inline typename tools::promote_args<T1, T2>::type hypot(T1 x, T2 y) { typedef typename tools::promote_args<T1, T2>::type result_type; return detail::hypot_imp( static_cast<result_type>(x), static_cast<result_type>(y), policies::policy<>()); } template <class T1, class T2, class Policy> inline typename tools::promote_args<T1, T2>::type hypot(T1 x, T2 y, const Policy& pol) { typedef typename tools::promote_args<T1, T2>::type result_type; return detail::hypot_imp( static_cast<result_type>(x), static_cast<result_type>(y), pol); } } // namespace math } // namespace boost #endif // BOOST_MATH_HYPOT_INCLUDED