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_DETAILS_INCLUDED
williamr@2: #define BOOST_MATH_COMPLEX_DETAILS_INCLUDED
williamr@2: //
williamr@2: // This header contains all the support code that is common to the
williamr@2: // inverse trig complex functions, it also contains all the includes
williamr@2: // that we need to implement all these functions.
williamr@2: //
williamr@2: #include <boost/detail/workaround.hpp>
williamr@2: #include <boost/config.hpp>
williamr@2: #include <boost/config/no_tr1/complex.hpp>
williamr@2: #include <boost/limits.hpp>
williamr@2: #include <math.h> // isnan where available
williamr@2: #include <cmath>
williamr@2: 
williamr@2: #ifdef BOOST_NO_STDC_NAMESPACE
williamr@2: namespace std{ using ::sqrt; }
williamr@2: #endif
williamr@2: 
williamr@2: namespace boost{ namespace math{ namespace detail{
williamr@2: 
williamr@2: template <class T>
williamr@2: inline bool test_is_nan(T t)
williamr@2: {
williamr@2:    // Comparisons with Nan's always fail:
williamr@2:    return std::numeric_limits<T>::has_infinity && (!(t <= std::numeric_limits<T>::infinity()) || !(t >= -std::numeric_limits<T>::infinity()));
williamr@2: }
williamr@2: #ifdef isnan
williamr@2: template<> inline bool test_is_nan<float>(float t) { return isnan(t); }
williamr@2: template<> inline bool test_is_nan<double>(double t) { return isnan(t); }
williamr@2: template<> inline bool test_is_nan<long double>(long double t) { return isnan(t); }
williamr@2: #endif
williamr@2: 
williamr@2: template <class T>
williamr@2: inline T mult_minus_one(const T& t)
williamr@2: {
williamr@2:    return test_is_nan(t) ? t : -t;
williamr@2: }
williamr@2: 
williamr@2: template <class T>
williamr@2: inline std::complex<T> mult_i(const std::complex<T>& t)
williamr@2: {
williamr@2:    return std::complex<T>(mult_minus_one(t.imag()), t.real());
williamr@2: }
williamr@2: 
williamr@2: template <class T>
williamr@2: inline std::complex<T> mult_minus_i(const std::complex<T>& t)
williamr@2: {
williamr@2:    return std::complex<T>(t.imag(), mult_minus_one(t.real()));
williamr@2: }
williamr@2: 
williamr@2: template <class T>
williamr@2: inline T safe_max(T t)
williamr@2: {
williamr@2:    return std::sqrt((std::numeric_limits<T>::max)()) / t;
williamr@2: }
williamr@2: inline long double safe_max(long double t)
williamr@2: {
williamr@2:    // long double sqrt often returns infinity due to
williamr@2:    // insufficient internal precision:
williamr@2:    return std::sqrt((std::numeric_limits<double>::max)()) / t;
williamr@2: }
williamr@2: #if BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x564))
williamr@2: // workaround for type deduction bug:
williamr@2: inline float safe_max(float t)
williamr@2: {
williamr@2:    return std::sqrt((std::numeric_limits<float>::max)()) / t;
williamr@2: }
williamr@2: inline double safe_max(double t)
williamr@2: {
williamr@2:    return std::sqrt((std::numeric_limits<double>::max)()) / t;
williamr@2: }
williamr@2: #endif
williamr@2: template <class T>
williamr@2: inline T safe_min(T t)
williamr@2: {
williamr@2:    return std::sqrt((std::numeric_limits<T>::min)()) * t;
williamr@2: }
williamr@2: inline long double safe_min(long double t)
williamr@2: {
williamr@2:    // long double sqrt often returns zero due to
williamr@2:    // insufficient internal precision:
williamr@2:    return std::sqrt((std::numeric_limits<double>::min)()) * t;
williamr@2: }
williamr@2: #if BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x564))
williamr@2: // type deduction workaround:
williamr@2: inline double safe_min(double t)
williamr@2: {
williamr@2:    return std::sqrt((std::numeric_limits<double>::min)()) * t;
williamr@2: }
williamr@2: inline float safe_min(float t)
williamr@2: {
williamr@2:    return std::sqrt((std::numeric_limits<float>::min)()) * t;
williamr@2: }
williamr@2: #endif
williamr@2: 
williamr@2: } } } // namespaces
williamr@2: 
williamr@2: #endif // BOOST_MATH_COMPLEX_DETAILS_INCLUDED
williamr@2: