boost/numeric/interval/interval.hpp
/* Boost interval/interval.hpp header file
*
* Copyright Herv� Br�nnimann, Guillaume Melquiond, Sylvain Pion 2002-2003
* Permission to use, copy, modify, sell, and distribute this software
* is hereby granted without fee provided that the above copyright notice
* appears in all copies and that both that copyright notice and this
* permission notice appear in supporting documentation,
*
* None of the above authors nor Polytechnic University make any
* representation about the suitability of this software for any
* purpose. It is provided "as is" without express or implied warranty.
*
* $Id: interval.hpp,v 1.3 2003/05/30 06:31:11 gmelquio Exp $
*/
#ifndef BOOST_NUMERIC_INTERVAL_INTERVAL_HPP
#define BOOST_NUMERIC_INTERVAL_INTERVAL_HPP
#include <stdexcept>
#include <boost/numeric/interval/detail/interval_prototype.hpp>
namespace boost {
namespace numeric {
namespace interval_lib {
class comparison_error
: public std::runtime_error
{
public:
comparison_error()
: std::runtime_error("boost::interval: uncertain comparison")
{ }
};
} // namespace interval_lib
/*
* interval class
*/
template<class T, class Policies>
class interval
{
private:
struct interval_holder;
struct number_holder;
public:
typedef T base_type;
typedef Policies traits_type;
interval(const T& v = static_cast<T>(0));
interval(const T& l, const T& u);
// The following needs to be defined in the class body for VC++.
template<class Policies2>
interval(const interval<T, Policies2>& r)
: low(r.lower()), up(r.upper())
{
typedef typename Policies2::checking checking2;
if (checking2::is_empty(low, up)) set_empty();
}
// compiler-generated copy constructor and assignment operator are fine
interval& operator=(const T& x);
void assign(const T& l, const T& u);
static interval empty();
static interval whole();
static interval hull(const T& x, const T& y);
const T& lower() const;
const T& upper() const;
interval& operator+= (const T& r);
interval& operator+= (const interval& r);
interval& operator-= (const T& r);
interval& operator-= (const interval& r);
interval& operator*= (const T& r);
interval& operator*= (const interval& r);
interval& operator/= (const T& r);
interval& operator/= (const interval& r);
bool operator< (const interval_holder& r) const;
bool operator> (const interval_holder& r) const;
bool operator<= (const interval_holder& r) const;
bool operator>= (const interval_holder& r) const;
bool operator== (const interval_holder& r) const;
bool operator!= (const interval_holder& r) const;
bool operator< (const number_holder& r) const;
bool operator> (const number_holder& r) const;
bool operator<= (const number_holder& r) const;
bool operator>= (const number_holder& r) const;
bool operator== (const number_holder& r) const;
bool operator!= (const number_holder& r) const;
// the following is for internal use only, it is not a published interface
// nevertheless, it's public because friends don't always work correctly.
interval(const T& l, const T& u, bool): low(l), up(u) {}
void set_empty();
void set_whole();
void set(const T& l, const T& u);
private:
struct interval_holder {
template<class Policies2>
interval_holder(const interval<T, Policies2>& r)
: low(r.lower()), up(r.upper())
{
typedef typename Policies2::checking checking2;
if (checking2::is_empty(low, up))
throw interval_lib::comparison_error();
}
const T& low;
const T& up;
};
struct number_holder {
number_holder(const T& r) : val(r)
{
typedef typename Policies::checking checking;
if (checking::is_nan(r))
throw interval_lib::comparison_error();
}
const T& val;
};
typedef typename Policies::checking checking;
typedef typename Policies::rounding rounding;
T low;
T up;
};
template<class T, class Policies> inline
interval<T, Policies>::interval(const T& v): low(v), up(v)
{
if (checking::is_nan(v)) set_empty();
}
template<class T, class Policies> inline
interval<T, Policies>::interval(const T& l, const T& u): low(l), up(u)
{
if (checking::is_nan(l) || checking::is_nan(u) || !(l <= u))
set_empty();
}
template<class T, class Policies> inline
interval<T, Policies>& interval<T, Policies>::operator=(const T& x)
{
if (checking::is_nan(x)) set_empty();
else low = up = x;
return *this;
}
template<class T, class Policies> inline
void interval<T, Policies>::assign(const T& l, const T& u)
{
if (checking::is_nan(l) || checking::is_nan(u) || !(l <= u))
set_empty();
else set(l, u);
}
template<class T, class Policies> inline
void interval<T, Policies>::set(const T& l, const T& u)
{
low = l;
up = u;
}
template<class T, class Policies> inline
void interval<T, Policies>::set_empty()
{
low = checking::empty_lower();
up = checking::empty_upper();
}
template<class T, class Policies> inline
void interval<T, Policies>::set_whole()
{
const T& inf = checking::inf();
low = -inf;
up = inf;
}
template<class T, class Policies> inline
interval<T, Policies> interval<T, Policies>::hull(const T& x, const T& y)
{
bool bad_x = checking::is_nan(x);
bool bad_y = checking::is_nan(y);
if (bad_x)
if (bad_y) return interval::empty();
else return interval(y, y, true);
else
if (bad_y) return interval(x, x, true);
if (x < y) return interval(x, y, true);
else return interval(y, x, true);
}
template<class T, class Policies> inline
interval<T, Policies> interval<T, Policies>::empty()
{
return interval<T, Policies>(checking::empty_lower(),
checking::empty_upper(), true);
}
template<class T, class Policies> inline
interval<T, Policies> interval<T, Policies>::whole()
{
const T& inf = checking::inf();
return interval<T, Policies>(-inf, inf, true);
}
template<class T, class Policies> inline
const T& interval<T, Policies>::lower() const
{
return low;
}
template<class T, class Policies> inline
const T& interval<T, Policies>::upper() const
{
return up;
}
/*
* interval/interval comparisons
*/
template<class T, class Policies> inline
bool interval<T, Policies>::operator< (const interval_holder& r) const
{
if (!checking::is_empty(low, up)) {
if (up < r.low) return true;
else if (low >= r.up) return false;
}
throw interval_lib::comparison_error();
}
template<class T, class Policies> inline
bool interval<T, Policies>::operator> (const interval_holder& r) const
{
if (!checking::is_empty(low, up)) {
if (low > r.up) return true;
else if (up <= r.low) return false;
}
throw interval_lib::comparison_error();
}
template<class T, class Policies> inline
bool interval<T, Policies>::operator<= (const interval_holder& r) const
{
if (!checking::is_empty(low, up)) {
if (up <= r.low) return true;
else if (low > r.up) return false;
}
throw interval_lib::comparison_error();
}
template<class T, class Policies> inline
bool interval<T, Policies>::operator>= (const interval_holder& r) const
{
if (!checking::is_empty(low, up)) {
if (low >= r.up) return true;
else if (up < r.low) return false;
}
throw interval_lib::comparison_error();
}
template<class T, class Policies> inline
bool interval<T, Policies>::operator== (const interval_holder& r) const
{
if (!checking::is_empty(low, up)) {
if (up == r.low && low == r.up) return true;
else if (up < r.low || low > r.up) return false;
}
throw interval_lib::comparison_error();
}
template<class T, class Policies> inline
bool interval<T, Policies>::operator!= (const interval_holder& r) const
{
if (!checking::is_empty(low, up)) {
if (up < r.low || low > r.up) return true;
else if (up == r.low && low == r.up) return false;
}
throw interval_lib::comparison_error();
}
/*
* interval/number comparisons
*/
template<class T, class Policies> inline
bool interval<T, Policies>::operator< (const number_holder& r) const
{
if (!checking::is_empty(low, up)) {
if (up < r.val) return true;
else if (low >= r.val) return false;
}
throw interval_lib::comparison_error();
}
template<class T, class Policies> inline
bool interval<T, Policies>::operator> (const number_holder& r) const
{
if (!checking::is_empty(low, up)) {
if (low > r.val) return true;
else if (up <= r.val) return false;
}
throw interval_lib::comparison_error();
}
template<class T, class Policies> inline
bool interval<T, Policies>::operator<= (const number_holder& r) const
{
if (!checking::is_empty(low, up)) {
if (up <= r.val) return true;
else if (low > r.val) return false;
}
throw interval_lib::comparison_error();
}
template<class T, class Policies> inline
bool interval<T, Policies>::operator>= (const number_holder& r) const
{
if (!checking::is_empty(low, up)) {
if (low >= r.val) return true;
else if (up < r.val) return false;
}
throw interval_lib::comparison_error();
}
template<class T, class Policies> inline
bool interval<T, Policies>::operator== (const number_holder& r) const
{
if (!checking::is_empty(low, up)) {
if (up == r.val && low == r.val) return true;
else if (up < r.val || low > r.val) return false;
}
throw interval_lib::comparison_error();
}
template<class T, class Policies> inline
bool interval<T, Policies>::operator!= (const number_holder& r) const
{
if (!checking::is_empty(low, up)) {
if (up < r.val || low > r.val) return true;
else if (up == r.val && low == r.val) return false;
}
throw interval_lib::comparison_error();
}
} // namespace numeric
} // namespace boost
#endif // BOOST_NUMERIC_INTERVAL_INTERVAL_HPP