mirror of
https://github.com/bolero-MURAKAMI/Sprout.git
synced 2024-11-16 10:49:05 +00:00
235 lines
7.3 KiB
C++
235 lines
7.3 KiB
C++
/*=============================================================================
|
|
Copyright (c) 2011-2014 Bolero MURAKAMI
|
|
https://github.com/bolero-MURAKAMI/Sprout
|
|
|
|
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 SPROUT_DETAIL_FLOAT_HPP
|
|
#define SPROUT_DETAIL_FLOAT_HPP
|
|
|
|
#include <type_traits>
|
|
#include <sprout/config.hpp>
|
|
#include <sprout/math/abs.hpp>
|
|
#include <sprout/math/floor.hpp>
|
|
#include <sprout/math/round.hpp>
|
|
#include <sprout/type_traits/enabler_if.hpp>
|
|
#include <sprout/utility/pair/pair.hpp>
|
|
#include <sprout/detail/pow.hpp>
|
|
|
|
namespace sprout {
|
|
namespace detail {
|
|
//
|
|
// float_pow10
|
|
//
|
|
template<
|
|
typename FloatType,
|
|
typename sprout::enabler_if<std::is_floating_point<FloatType>::value>::type = sprout::enabler
|
|
>
|
|
inline SPROUT_CONSTEXPR FloatType
|
|
float_pow10(int exponent) {
|
|
return sprout::detail::pow_n(FloatType(10), exponent);
|
|
}
|
|
|
|
//
|
|
// float_exponent10
|
|
//
|
|
template<typename FloatType>
|
|
inline SPROUT_CONSTEXPR sprout::pair<int, FloatType>
|
|
float_exponent10_positive_1(sprout::pair<int, FloatType> const& current, int n) {
|
|
typedef sprout::pair<int, FloatType> type;
|
|
return (current.second) < 10 ? current
|
|
: n == 1 ? type(current.first + 1, current.second / 10)
|
|
: sprout::detail::float_exponent10_positive_1(
|
|
sprout::detail::float_exponent10_positive_1(
|
|
current,
|
|
n / 2
|
|
),
|
|
n - n / 2
|
|
)
|
|
;
|
|
}
|
|
template<typename FloatType>
|
|
inline SPROUT_CONSTEXPR sprout::pair<int, FloatType>
|
|
float_exponent10_positive_0(sprout::pair<int, FloatType> const& current, int n) {
|
|
return (current.second) < 10 ? current
|
|
: sprout::detail::float_exponent10_positive_0(
|
|
sprout::detail::float_exponent10_positive_1(
|
|
current,
|
|
n
|
|
),
|
|
n * 2
|
|
)
|
|
;
|
|
}
|
|
template<typename FloatType>
|
|
inline SPROUT_CONSTEXPR int
|
|
float_exponent10_positive(FloatType val) {
|
|
typedef sprout::pair<int, FloatType> type;
|
|
return float_exponent10_positive_0(type(val, 0), 1).first;
|
|
}
|
|
template<typename FloatType>
|
|
inline SPROUT_CONSTEXPR sprout::pair<int, FloatType>
|
|
float_exponent10_negative_1(sprout::pair<int, FloatType> const& current, int n) {
|
|
typedef sprout::pair<int, FloatType> type;
|
|
return !((current.second) < 1) ? current
|
|
: n == 1 ? type(current.first + 1, current.second * 10)
|
|
: sprout::detail::float_exponent10_negative_1(
|
|
sprout::detail::float_exponent10_negative_1(
|
|
current,
|
|
n / 2
|
|
),
|
|
n - n / 2
|
|
)
|
|
;
|
|
}
|
|
template<typename FloatType>
|
|
inline SPROUT_CONSTEXPR sprout::pair<int, FloatType>
|
|
float_exponent10_negative_0(sprout::pair<int, FloatType> const& current, int n) {
|
|
return !((current.second) < 1) ? current
|
|
: sprout::detail::float_exponent10_negative_0(
|
|
sprout::detail::float_exponent10_negative_1(
|
|
current,
|
|
n
|
|
),
|
|
n * 2
|
|
)
|
|
;
|
|
}
|
|
template<typename FloatType>
|
|
inline SPROUT_CONSTEXPR int
|
|
float_exponent10_negative(FloatType val) {
|
|
typedef sprout::pair<int, FloatType> type;
|
|
return float_exponent10_negative_0(type(val, 0), 1).first;
|
|
}
|
|
// !!! OLD:
|
|
// template<typename FloatType>
|
|
// inline SPROUT_CONSTEXPR int
|
|
// float_exponent10_positive(FloatType val) {
|
|
// return val < 10 ? 0
|
|
// : 1 + sprout::detail::float_exponent10_positive(val / 10)
|
|
// ;
|
|
// }
|
|
// template<typename FloatType>
|
|
// inline SPROUT_CONSTEXPR int
|
|
// float_exponent10_negative(FloatType val) {
|
|
// return val < 1 ? 1 + sprout::detail::float_exponent10_negative(val * 10)
|
|
// : 0
|
|
// ;
|
|
// }
|
|
template<
|
|
typename FloatType,
|
|
typename sprout::enabler_if<std::is_floating_point<FloatType>::value>::type = sprout::enabler
|
|
>
|
|
inline SPROUT_CONSTEXPR int
|
|
float_exponent10(FloatType val) {
|
|
return val < 0
|
|
? val > -1
|
|
? sprout::detail::float_exponent10_negative(-val)
|
|
: sprout::detail::float_exponent10_positive(-val)
|
|
: val < 1
|
|
? sprout::detail::float_exponent10_negative(val)
|
|
: sprout::detail::float_exponent10_positive(val)
|
|
;
|
|
}
|
|
|
|
//
|
|
// float_digit_at
|
|
//
|
|
template<typename FloatType>
|
|
inline SPROUT_CONSTEXPR int
|
|
float_digit_of_impl(FloatType val) {
|
|
return static_cast<int>((val - sprout::math::floor(val)) * 10);
|
|
}
|
|
template<
|
|
typename FloatType,
|
|
typename sprout::enabler_if<std::is_floating_point<FloatType>::value>::type = sprout::enabler
|
|
>
|
|
inline SPROUT_CONSTEXPR int
|
|
float_digit_at(FloatType val, int digits) {
|
|
return sprout::detail::float_digit_of_impl(val / sprout::detail::float_pow10<FloatType>(digits + 1));
|
|
}
|
|
|
|
//
|
|
// float_digits
|
|
//
|
|
template<typename FloatType>
|
|
inline SPROUT_CONSTEXPR sprout::pair<int, FloatType>
|
|
float_digits_impl_1(sprout::pair<int, FloatType> const& current, FloatType val, int n) {
|
|
typedef sprout::pair<int, FloatType> type;
|
|
return (val / current.second) < 1 ? current
|
|
: n == 1 ? type(current.first + 1, current.second * FloatType(10))
|
|
: sprout::detail::float_digits_impl_1(
|
|
sprout::detail::float_digits_impl_1(
|
|
current,
|
|
val, n / 2
|
|
),
|
|
val, n - n / 2
|
|
)
|
|
;
|
|
}
|
|
template<typename FloatType>
|
|
inline SPROUT_CONSTEXPR sprout::pair<int, FloatType>
|
|
float_digits_impl(sprout::pair<int, FloatType> const& current, FloatType val, int n) {
|
|
return (val / current.second) < 1 ? current
|
|
: sprout::detail::float_digits_impl(
|
|
sprout::detail::float_digits_impl_1(
|
|
current,
|
|
val, n
|
|
),
|
|
val, n * 2
|
|
)
|
|
;
|
|
}
|
|
template<
|
|
typename FloatType,
|
|
typename sprout::enabler_if<std::is_floating_point<FloatType>::value>::type = sprout::enabler
|
|
>
|
|
inline SPROUT_CONSTEXPR int
|
|
float_digits(FloatType val) {
|
|
typedef sprout::pair<int, FloatType> type;
|
|
return val < 0
|
|
? val > -1 ? 1 : sprout::detail::float_digits_impl(type(1, FloatType(10)), -val, 1).first
|
|
: val < 1 ? 1 : sprout::detail::float_digits_impl(type(1, FloatType(10)), val, 1).first
|
|
;
|
|
}
|
|
|
|
//
|
|
// float_digits_checked
|
|
//
|
|
template<typename FloatType>
|
|
inline SPROUT_CONSTEXPR int
|
|
float_digits_checked_impl(FloatType val, int digits) {
|
|
return val == 0 ? digits
|
|
: sprout::detail::float_digit_at(val, digits - 1) == 0 ? digits - 1 : digits
|
|
;
|
|
}
|
|
template<
|
|
typename FloatType,
|
|
typename sprout::enabler_if<std::is_floating_point<FloatType>::value>::type = sprout::enabler
|
|
>
|
|
inline SPROUT_CONSTEXPR int
|
|
float_digits_checked(FloatType val) {
|
|
return sprout::detail::float_digits_checked_impl(val, sprout::detail::float_digits(val));
|
|
}
|
|
|
|
//
|
|
// float_round_at
|
|
//
|
|
template<typename FloatType>
|
|
inline SPROUT_CONSTEXPR FloatType
|
|
float_round_impl(FloatType val, FloatType p10) {
|
|
return sprout::math::round(val * p10) / p10;
|
|
}
|
|
template<
|
|
typename FloatType,
|
|
typename sprout::enabler_if<std::is_floating_point<FloatType>::value>::type = sprout::enabler
|
|
>
|
|
inline SPROUT_CONSTEXPR FloatType
|
|
float_round_at(FloatType val, int digits) {
|
|
return sprout::detail::float_round_impl(val, sprout::detail::float_pow10<FloatType>(digits));
|
|
}
|
|
} // namespace detail
|
|
} // namespace sprout
|
|
|
|
#endif // #ifndef SPROUT_DETAIL_FLOAT_HPP
|