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vn-verdnaturachat/ios/Pods/boost-for-react-native/boost/units/static_rational.hpp

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// Boost.Units - A C++ library for zero-overhead dimensional analysis and
// unit/quantity manipulation and conversion
//
// Copyright (C) 2003-2008 Matthias Christian Schabel
// Copyright (C) 2008 Steven Watanabe
//
// 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_UNITS_STATIC_RATIONAL_HPP
#define BOOST_UNITS_STATIC_RATIONAL_HPP
#include <boost/integer/common_factor_ct.hpp>
#include <boost/mpl/less.hpp>
#include <boost/mpl/arithmetic.hpp>
#ifdef __BORLANDC__
#include <boost/mpl/eval_if.hpp>
#include <boost/mpl/integral_c.hpp>
#include <boost/mpl/identity.hpp>
#endif
#include <boost/units/config.hpp>
#include <boost/units/operators.hpp>
/// \file
/// \brief Compile-time rational numbers and operators.
namespace boost {
namespace units {
namespace detail {
struct static_rational_tag {};
}
typedef long integer_type;
/// Compile time absolute value.
template<integer_type Value>
struct static_abs
{
BOOST_STATIC_CONSTANT(integer_type,value = Value < 0 ? -Value : Value);
};
// Compile time rational number.
/**
This is an implementation of a compile time rational number, where @c static_rational<N,D> represents
a rational number with numerator @c N and denominator @c D. Because of the potential for ambiguity arising
from multiple equivalent values of @c static_rational (e.g. @c static_rational<6,2>==static_rational<3>),
static rationals should always be accessed through @c static_rational<N,D>::type. Template specialization
prevents instantiation of zero denominators (i.e. @c static_rational<N,0>). The following compile-time
arithmetic operators are provided for static_rational variables only (no operators are defined between
long and static_rational):
- @c mpl::negate
- @c mpl::plus
- @c mpl::minus
- @c mpl::times
- @c mpl::divides
Neither @c static_power nor @c static_root are defined for @c static_rational. This is because template types
may not be floating point values, while powers and roots of rational numbers can produce floating point
values.
*/
#ifdef __BORLANDC__
template<integer_type X>
struct make_integral_c {
typedef boost::mpl::integral_c<integer_type, X> type;
};
template<integer_type N,integer_type D = 1>
class static_rational
{
public:
typedef static_rational this_type;
typedef boost::mpl::integral_c<integer_type, N> N_type;
typedef boost::mpl::integral_c<integer_type, D> D_type;
typedef typename make_integral_c<
(::boost::integer::static_gcd<
::boost::units::static_abs<N>::value,
::boost::units::static_abs<D>::value
>::value)>::type gcd_type;
typedef typename boost::mpl::eval_if<
boost::mpl::less<
D_type,
boost::mpl::integral_c<integer_type, 0>
>,
boost::mpl::negate<gcd_type>,
gcd_type
>::type den_type;
public:
// for mpl arithmetic support
typedef detail::static_rational_tag tag;
BOOST_STATIC_CONSTANT(integer_type, Numerator =
(::boost::mpl::divides<N_type, den_type>::value));
BOOST_STATIC_CONSTANT(integer_type, Denominator =
(::boost::mpl::divides<D_type, den_type>::value));
/// INTERNAL ONLY
typedef static_rational<N,D> this_type;
/// static_rational<N,D> reduced by GCD
typedef static_rational<
(::boost::mpl::divides<N_type, den_type>::value),
(::boost::mpl::divides<D_type, den_type>::value)
> type;
static integer_type numerator() { return Numerator; }
static integer_type denominator() { return Denominator; }
// INTERNAL ONLY
static_rational() { }
//~static_rational() { }
};
#else
template<integer_type N,integer_type D = 1>
class static_rational
{
private:
static const integer_type nabs = static_abs<N>::value,
dabs = static_abs<D>::value;
/// greatest common divisor of N and D
// need cast to signed because static_gcd returns unsigned long
static const integer_type den =
static_cast<integer_type>(boost::integer::static_gcd<nabs,dabs>::value) * ((D < 0) ? -1 : 1);
public:
// for mpl arithmetic support
typedef detail::static_rational_tag tag;
static const integer_type Numerator = N/den,
Denominator = D/den;
/// INTERNAL ONLY
typedef static_rational<N,D> this_type;
/// static_rational<N,D> reduced by GCD
typedef static_rational<Numerator,Denominator> type;
static integer_type numerator() { return Numerator; }
static integer_type denominator() { return Denominator; }
// INTERNAL ONLY
static_rational() { }
//~static_rational() { }
};
#endif
}
}
#if BOOST_UNITS_HAS_BOOST_TYPEOF
#include BOOST_TYPEOF_INCREMENT_REGISTRATION_GROUP()
BOOST_TYPEOF_REGISTER_TEMPLATE(boost::units::static_rational, (long)(long))
#endif
namespace boost {
namespace units {
// prohibit zero denominator
template<integer_type N> class static_rational<N,0>;
/// get decimal value of @c static_rational
template<class T,integer_type N,integer_type D>
inline typename divide_typeof_helper<T,T>::type
value(const static_rational<N,D>&)
{
return T(N)/T(D);
}
} // namespace units
#ifndef BOOST_UNITS_DOXYGEN
namespace mpl {
#ifdef __BORLANDC__
template<>
struct plus_impl<boost::units::detail::static_rational_tag, boost::units::detail::static_rational_tag>
{
template<class T0, class T1>
struct apply {
typedef typename boost::units::static_rational<
::boost::mpl::plus<
boost::mpl::times<typename T0::N_type, typename T1::D_type>,
boost::mpl::times<typename T1::N_type, typename T0::D_type>
>::value,
::boost::mpl::times<typename T0::D_type, typename T1::D_type>::value
>::type type;
};
};
template<>
struct minus_impl<boost::units::detail::static_rational_tag, boost::units::detail::static_rational_tag>
{
template<class T0, class T1>
struct apply {
typedef typename boost::units::static_rational<
::boost::mpl::minus<
boost::mpl::times<typename T0::N_type, typename T1::D_type>,
boost::mpl::times<typename T1::N_type, typename T0::D_type>
>::value,
::boost::mpl::times<typename T0::D_type, typename T1::D_type>::value
>::type type;
};
};
template<>
struct times_impl<boost::units::detail::static_rational_tag, boost::units::detail::static_rational_tag>
{
template<class T0, class T1>
struct apply {
typedef typename boost::units::static_rational<
::boost::mpl::times<typename T0::N_type, typename T1::N_type>::value,
::boost::mpl::times<typename T0::D_type, typename T1::D_type>::value
>::type type;
};
};
template<>
struct divides_impl<boost::units::detail::static_rational_tag, boost::units::detail::static_rational_tag>
{
template<class T0, class T1>
struct apply {
typedef typename boost::units::static_rational<
::boost::mpl::times<typename T0::N_type, typename T1::D_type>::value,
::boost::mpl::times<typename T0::D_type, typename T1::N_type>::value
>::type type;
};
};
template<>
struct negate_impl<boost::units::detail::static_rational_tag>
{
template<class T0>
struct apply {
typedef typename boost::units::static_rational<
::boost::mpl::negate<typename T0::N_type>::value,
::boost::mpl::identity<T0>::type::Denominator
>::type type;
};
};
template<>
struct less_impl<boost::units::detail::static_rational_tag, boost::units::detail::static_rational_tag>
{
template<class T0, class T1>
struct apply
{
typedef mpl::bool_<((mpl::minus<T0, T1>::type::Numerator) < 0)> type;
};
};
#else
template<>
struct plus_impl<boost::units::detail::static_rational_tag, boost::units::detail::static_rational_tag>
{
template<class T0, class T1>
struct apply {
typedef typename boost::units::static_rational<
T0::Numerator*T1::Denominator+T1::Numerator*T0::Denominator,
T0::Denominator*T1::Denominator
>::type type;
};
};
template<>
struct minus_impl<boost::units::detail::static_rational_tag, boost::units::detail::static_rational_tag>
{
template<class T0, class T1>
struct apply {
typedef typename boost::units::static_rational<
T0::Numerator*T1::Denominator-T1::Numerator*T0::Denominator,
T0::Denominator*T1::Denominator
>::type type;
};
};
template<>
struct times_impl<boost::units::detail::static_rational_tag, boost::units::detail::static_rational_tag>
{
template<class T0, class T1>
struct apply {
typedef typename boost::units::static_rational<
T0::Numerator*T1::Numerator,
T0::Denominator*T1::Denominator
>::type type;
};
};
template<>
struct divides_impl<boost::units::detail::static_rational_tag, boost::units::detail::static_rational_tag>
{
template<class T0, class T1>
struct apply {
typedef typename boost::units::static_rational<
T0::Numerator*T1::Denominator,
T0::Denominator*T1::Numerator
>::type type;
};
};
template<>
struct negate_impl<boost::units::detail::static_rational_tag>
{
template<class T0>
struct apply {
typedef typename boost::units::static_rational<-T0::Numerator,T0::Denominator>::type type;
};
};
template<>
struct less_impl<boost::units::detail::static_rational_tag, boost::units::detail::static_rational_tag>
{
template<class T0, class T1>
struct apply
{
typedef mpl::bool_<((mpl::minus<T0, T1>::type::Numerator) < 0)> type;
};
};
#endif
}
#endif
} // namespace boost
#endif // BOOST_UNITS_STATIC_RATIONAL_HPP
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