/* Boost interval/detail/division.hpp file | |
* | |
* Copyright 2003 Guillaume Melquiond, Sylvain Pion | |
* | |
* Distributed under 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_NUMERIC_INTERVAL_DETAIL_DIVISION_HPP | |
#define BOOST_NUMERIC_INTERVAL_DETAIL_DIVISION_HPP | |
#include <boost/numeric/interval/detail/interval_prototype.hpp> | |
#include <boost/numeric/interval/detail/bugs.hpp> | |
#include <boost/numeric/interval/detail/test_input.hpp> | |
#include <boost/numeric/interval/rounded_arith.hpp> | |
#include <algorithm> | |
namespace boost { | |
namespace numeric { | |
namespace interval_lib { | |
namespace detail { | |
template<class T, class Policies> inline | |
interval<T, Policies> div_non_zero(const interval<T, Policies>& x, | |
const interval<T, Policies>& y) | |
{ | |
// assert(!in_zero(y)); | |
typename Policies::rounding rnd; | |
typedef interval<T, Policies> I; | |
const T& xl = x.lower(); | |
const T& xu = x.upper(); | |
const T& yl = y.lower(); | |
const T& yu = y.upper(); | |
if (::boost::numeric::interval_lib::user::is_neg(xu)) | |
if (::boost::numeric::interval_lib::user::is_neg(yu)) | |
return I(rnd.div_down(xu, yl), rnd.div_up(xl, yu), true); | |
else | |
return I(rnd.div_down(xl, yl), rnd.div_up(xu, yu), true); | |
else if (::boost::numeric::interval_lib::user::is_neg(xl)) | |
if (::boost::numeric::interval_lib::user::is_neg(yu)) | |
return I(rnd.div_down(xu, yu), rnd.div_up(xl, yu), true); | |
else | |
return I(rnd.div_down(xl, yl), rnd.div_up(xu, yl), true); | |
else | |
if (::boost::numeric::interval_lib::user::is_neg(yu)) | |
return I(rnd.div_down(xu, yu), rnd.div_up(xl, yl), true); | |
else | |
return I(rnd.div_down(xl, yu), rnd.div_up(xu, yl), true); | |
} | |
template<class T, class Policies> inline | |
interval<T, Policies> div_non_zero(const T& x, const interval<T, Policies>& y) | |
{ | |
// assert(!in_zero(y)); | |
typename Policies::rounding rnd; | |
typedef interval<T, Policies> I; | |
const T& yl = y.lower(); | |
const T& yu = y.upper(); | |
if (::boost::numeric::interval_lib::user::is_neg(x)) | |
return I(rnd.div_down(x, yl), rnd.div_up(x, yu), true); | |
else | |
return I(rnd.div_down(x, yu), rnd.div_up(x, yl), true); | |
} | |
template<class T, class Policies> inline | |
interval<T, Policies> div_positive(const interval<T, Policies>& x, const T& yu) | |
{ | |
// assert(::boost::numeric::interval_lib::user::is_pos(yu)); | |
if (::boost::numeric::interval_lib::user::is_zero(x.lower()) && | |
::boost::numeric::interval_lib::user::is_zero(x.upper())) | |
return x; | |
typename Policies::rounding rnd; | |
typedef interval<T, Policies> I; | |
const T& xl = x.lower(); | |
const T& xu = x.upper(); | |
typedef typename Policies::checking checking; | |
if (::boost::numeric::interval_lib::user::is_neg(xu)) | |
return I(checking::neg_inf(), rnd.div_up(xu, yu), true); | |
else if (::boost::numeric::interval_lib::user::is_neg(xl)) | |
return I(checking::neg_inf(), checking::pos_inf(), true); | |
else | |
return I(rnd.div_down(xl, yu), checking::pos_inf(), true); | |
} | |
template<class T, class Policies> inline | |
interval<T, Policies> div_positive(const T& x, const T& yu) | |
{ | |
// assert(::boost::numeric::interval_lib::user::is_pos(yu)); | |
typedef interval<T, Policies> I; | |
if (::boost::numeric::interval_lib::user::is_zero(x)) | |
return I(static_cast<T>(0), static_cast<T>(0), true); | |
typename Policies::rounding rnd; | |
typedef typename Policies::checking checking; | |
if (::boost::numeric::interval_lib::user::is_neg(x)) | |
return I(checking::neg_inf(), rnd.div_up(x, yu), true); | |
else | |
return I(rnd.div_down(x, yu), checking::pos_inf(), true); | |
} | |
template<class T, class Policies> inline | |
interval<T, Policies> div_negative(const interval<T, Policies>& x, const T& yl) | |
{ | |
// assert(::boost::numeric::interval_lib::user::is_neg(yl)); | |
if (::boost::numeric::interval_lib::user::is_zero(x.lower()) && | |
::boost::numeric::interval_lib::user::is_zero(x.upper())) | |
return x; | |
typename Policies::rounding rnd; | |
typedef interval<T, Policies> I; | |
const T& xl = x.lower(); | |
const T& xu = x.upper(); | |
typedef typename Policies::checking checking; | |
if (::boost::numeric::interval_lib::user::is_neg(xu)) | |
return I(rnd.div_down(xu, yl), checking::pos_inf(), true); | |
else if (::boost::numeric::interval_lib::user::is_neg(xl)) | |
return I(checking::neg_inf(), checking::pos_inf(), true); | |
else | |
return I(checking::neg_inf(), rnd.div_up(xl, yl), true); | |
} | |
template<class T, class Policies> inline | |
interval<T, Policies> div_negative(const T& x, const T& yl) | |
{ | |
// assert(::boost::numeric::interval_lib::user::is_neg(yl)); | |
typedef interval<T, Policies> I; | |
if (::boost::numeric::interval_lib::user::is_zero(x)) | |
return I(static_cast<T>(0), static_cast<T>(0), true); | |
typename Policies::rounding rnd; | |
typedef typename Policies::checking checking; | |
if (::boost::numeric::interval_lib::user::is_neg(x)) | |
return I(rnd.div_down(x, yl), checking::pos_inf(), true); | |
else | |
return I(checking::neg_inf(), rnd.div_up(x, yl), true); | |
} | |
template<class T, class Policies> inline | |
interval<T, Policies> div_zero(const interval<T, Policies>& x) | |
{ | |
if (::boost::numeric::interval_lib::user::is_zero(x.lower()) && | |
::boost::numeric::interval_lib::user::is_zero(x.upper())) | |
return x; | |
else return interval<T, Policies>::whole(); | |
} | |
template<class T, class Policies> inline | |
interval<T, Policies> div_zero(const T& x) | |
{ | |
if (::boost::numeric::interval_lib::user::is_zero(x)) | |
return interval<T, Policies>(static_cast<T>(0), static_cast<T>(0), true); | |
else return interval<T, Policies>::whole(); | |
} | |
template<class T, class Policies> inline | |
interval<T, Policies> div_zero_part1(const interval<T, Policies>& x, | |
const interval<T, Policies>& y, bool& b) | |
{ | |
// assert(::boost::numeric::interval_lib::user::is_neg(y.lower()) && ::boost::numeric::interval_lib::user::is_pos(y.upper())); | |
if (::boost::numeric::interval_lib::user::is_zero(x.lower()) && ::boost::numeric::interval_lib::user::is_zero(x.upper())) | |
{ b = false; return x; } | |
typename Policies::rounding rnd; | |
typedef interval<T, Policies> I; | |
const T& xl = x.lower(); | |
const T& xu = x.upper(); | |
const T& yl = y.lower(); | |
const T& yu = y.upper(); | |
typedef typename Policies::checking checking; | |
if (::boost::numeric::interval_lib::user::is_neg(xu)) | |
{ b = true; return I(checking::neg_inf(), rnd.div_up(xu, yu), true); } | |
else if (::boost::numeric::interval_lib::user::is_neg(xl)) | |
{ b = false; return I(checking::neg_inf(), checking::pos_inf(), true); } | |
else | |
{ b = true; return I(checking::neg_inf(), rnd.div_up(xl, yl), true); } | |
} | |
template<class T, class Policies> inline | |
interval<T, Policies> div_zero_part2(const interval<T, Policies>& x, | |
const interval<T, Policies>& y) | |
{ | |
// assert(::boost::numeric::interval_lib::user::is_neg(y.lower()) && ::boost::numeric::interval_lib::user::is_pos(y.upper()) && (div_zero_part1(x, y, b), b)); | |
typename Policies::rounding rnd; | |
typedef interval<T, Policies> I; | |
typedef typename Policies::checking checking; | |
if (::boost::numeric::interval_lib::user::is_neg(x.upper())) | |
return I(rnd.div_down(x.upper(), y.lower()), checking::pos_inf(), true); | |
else | |
return I(rnd.div_down(x.lower(), y.upper()), checking::pos_inf(), true); | |
} | |
} // namespace detail | |
} // namespace interval_lib | |
} // namespace numeric | |
} // namespace boost | |
#endif // BOOST_NUMERIC_INTERVAL_DETAIL_DIVISION_HPP |