mirror of
https://github.com/bolero-MURAKAMI/Sprout.git
synced 2024-11-14 10:39:05 +00:00
203 lines
6.9 KiB
C++
203 lines
6.9 KiB
C++
/*=============================================================================
|
|
Copyright (c) 2011-2015 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_MATH_SIGMOID_HPP
|
|
#define SPROUT_MATH_SIGMOID_HPP
|
|
|
|
#include <type_traits>
|
|
#include <sprout/config.hpp>
|
|
#include <sprout/math/detail/config.hpp>
|
|
#include <sprout/math/detail/float_compute.hpp>
|
|
#include <sprout/math/exp.hpp>
|
|
#include <sprout/type_traits/float_promote.hpp>
|
|
#include <sprout/type_traits/enabler_if.hpp>
|
|
|
|
namespace sprout {
|
|
namespace math {
|
|
//
|
|
// sigmoid
|
|
//
|
|
namespace detail {
|
|
template<typename T>
|
|
inline SPROUT_CONSTEXPR T
|
|
sigmoid_impl(T x){
|
|
return 1 / (1 + sprout::math::exp(-x));
|
|
}
|
|
template<typename T>
|
|
inline SPROUT_CONSTEXPR T
|
|
sigmoid_impl(T x, T a){
|
|
return sprout::math::detail::sigmoid_impl(a * x);
|
|
}
|
|
} // namespace detail
|
|
template<
|
|
typename FloatType,
|
|
typename sprout::enabler_if<std::is_floating_point<FloatType>::value>::type = sprout::enabler
|
|
>
|
|
inline SPROUT_CONSTEXPR FloatType
|
|
sigmoid(FloatType x){
|
|
return sprout::math::detail::sigmoid_impl(sprout::math::detail::as_float_compute(x));
|
|
}
|
|
template<
|
|
typename FloatType,
|
|
typename sprout::enabler_if<std::is_floating_point<FloatType>::value>::type = sprout::enabler
|
|
>
|
|
inline SPROUT_CONSTEXPR FloatType
|
|
sigmoid(FloatType x, FloatType a){
|
|
return sprout::math::detail::sigmoid_impl(sprout::math::detail::as_float_compute(x), sprout::math::detail::as_float_compute(a));
|
|
}
|
|
template<
|
|
typename IntType,
|
|
typename sprout::enabler_if<std::is_integral<IntType>::value>::type = sprout::enabler
|
|
>
|
|
inline SPROUT_CONSTEXPR double
|
|
sigmoid(IntType x) {
|
|
return sprout::math::sigmoid(static_cast<double>(x));
|
|
}
|
|
template<
|
|
typename ArithmeticType1,
|
|
typename ArithmeticType2,
|
|
typename sprout::enabler_if<
|
|
std::is_arithmetic<ArithmeticType1>::value && std::is_arithmetic<ArithmeticType2>::value
|
|
>::type = sprout::enabler
|
|
>
|
|
inline SPROUT_CONSTEXPR typename sprout::float_promote<ArithmeticType1, ArithmeticType2>::type
|
|
sigmoid(ArithmeticType1 x, ArithmeticType2 a) {
|
|
typedef typename sprout::float_promote<ArithmeticType1, ArithmeticType2>::type type;
|
|
return sprout::math::sigmoid(static_cast<type>(x), static_cast<type>(a));
|
|
}
|
|
|
|
//
|
|
// d_sigmoid
|
|
//
|
|
namespace detail {
|
|
template<typename T>
|
|
inline SPROUT_CONSTEXPR T
|
|
d_sigmoid_impl_1(T s){
|
|
return s * (1 - s);
|
|
}
|
|
template<typename T>
|
|
inline SPROUT_CONSTEXPR T
|
|
d_sigmoid_impl_1(T s, T a){
|
|
return a * s * (1 - s);
|
|
}
|
|
template<typename T>
|
|
inline SPROUT_CONSTEXPR T
|
|
d_sigmoid_impl(T x){
|
|
return sprout::math::detail::d_sigmoid_impl_1(sprout::math::sigmoid(x));
|
|
}
|
|
template<typename T>
|
|
inline SPROUT_CONSTEXPR T
|
|
d_sigmoid_impl(T x, T a){
|
|
return sprout::math::detail::d_sigmoid_impl_1(sprout::math::sigmoid(x, a), a);
|
|
}
|
|
} // namespace detail
|
|
template<
|
|
typename FloatType,
|
|
typename sprout::enabler_if<std::is_floating_point<FloatType>::value>::type = sprout::enabler
|
|
>
|
|
inline SPROUT_CONSTEXPR FloatType
|
|
d_sigmoid(FloatType x){
|
|
return sprout::math::detail::d_sigmoid_impl(sprout::math::detail::as_float_compute(x));
|
|
}
|
|
template<
|
|
typename FloatType,
|
|
typename sprout::enabler_if<std::is_floating_point<FloatType>::value>::type = sprout::enabler
|
|
>
|
|
inline SPROUT_CONSTEXPR FloatType
|
|
d_sigmoid(FloatType x, FloatType a){
|
|
return sprout::math::detail::d_sigmoid_impl(sprout::math::detail::as_float_compute(x), sprout::math::detail::as_float_compute(a));
|
|
}
|
|
template<
|
|
typename IntType,
|
|
typename sprout::enabler_if<std::is_integral<IntType>::value>::type = sprout::enabler
|
|
>
|
|
inline SPROUT_CONSTEXPR double
|
|
d_sigmoid(IntType x) {
|
|
return sprout::math::d_sigmoid(static_cast<double>(x));
|
|
}
|
|
template<
|
|
typename ArithmeticType1,
|
|
typename ArithmeticType2,
|
|
typename sprout::enabler_if<
|
|
std::is_arithmetic<ArithmeticType1>::value && std::is_arithmetic<ArithmeticType2>::value
|
|
>::type = sprout::enabler
|
|
>
|
|
inline SPROUT_CONSTEXPR typename sprout::float_promote<ArithmeticType1, ArithmeticType2>::type
|
|
d_sigmoid(ArithmeticType1 x, ArithmeticType2 a) {
|
|
typedef typename sprout::float_promote<ArithmeticType1, ArithmeticType2>::type type;
|
|
return sprout::math::d_sigmoid(static_cast<type>(x), static_cast<type>(a));
|
|
}
|
|
|
|
//
|
|
// d2_sigmoid
|
|
//
|
|
namespace detail {
|
|
template<typename T>
|
|
inline SPROUT_CONSTEXPR T
|
|
d2_sigmoid_impl_1(T s){
|
|
return s * (1 - s) * (1 - 2 * s);
|
|
}
|
|
template<typename T>
|
|
inline SPROUT_CONSTEXPR T
|
|
d2_sigmoid_impl_1(T s, T a){
|
|
return a * a * s * (1 - s) * (1 - 2 * s);
|
|
}
|
|
template<typename T>
|
|
inline SPROUT_CONSTEXPR T
|
|
d2_sigmoid_impl(T x){
|
|
return sprout::math::detail::d2_sigmoid_impl_1(sprout::math::sigmoid(x));
|
|
}
|
|
template<typename T>
|
|
inline SPROUT_CONSTEXPR T
|
|
d2_sigmoid_impl(T x, T a){
|
|
return sprout::math::detail::d2_sigmoid_impl_1(sprout::math::sigmoid(x, a), a);
|
|
}
|
|
} // namespace detail
|
|
template<
|
|
typename FloatType,
|
|
typename sprout::enabler_if<std::is_floating_point<FloatType>::value>::type = sprout::enabler
|
|
>
|
|
inline SPROUT_CONSTEXPR FloatType
|
|
d2_sigmoid(FloatType x){
|
|
return sprout::math::detail::d2_sigmoid_impl(sprout::math::detail::as_float_compute(x));
|
|
}
|
|
template<
|
|
typename FloatType,
|
|
typename sprout::enabler_if<std::is_floating_point<FloatType>::value>::type = sprout::enabler
|
|
>
|
|
inline SPROUT_CONSTEXPR FloatType
|
|
d2_sigmoid(FloatType x, FloatType a){
|
|
return sprout::math::detail::d2_sigmoid_impl(sprout::math::detail::as_float_compute(x), sprout::math::detail::as_float_compute(a));
|
|
}
|
|
template<
|
|
typename IntType,
|
|
typename sprout::enabler_if<std::is_integral<IntType>::value>::type = sprout::enabler
|
|
>
|
|
inline SPROUT_CONSTEXPR double
|
|
d2_sigmoid(IntType x) {
|
|
return sprout::math::d2_sigmoid(static_cast<double>(x));
|
|
}
|
|
template<
|
|
typename ArithmeticType1,
|
|
typename ArithmeticType2,
|
|
typename sprout::enabler_if<
|
|
std::is_arithmetic<ArithmeticType1>::value && std::is_arithmetic<ArithmeticType2>::value
|
|
>::type = sprout::enabler
|
|
>
|
|
inline SPROUT_CONSTEXPR typename sprout::float_promote<ArithmeticType1, ArithmeticType2>::type
|
|
d2_sigmoid(ArithmeticType1 x, ArithmeticType2 a) {
|
|
typedef typename sprout::float_promote<ArithmeticType1, ArithmeticType2>::type type;
|
|
return sprout::math::d2_sigmoid(static_cast<type>(x), static_cast<type>(a));
|
|
}
|
|
} // namespace math
|
|
|
|
using sprout::math::sigmoid;
|
|
using sprout::math::d_sigmoid;
|
|
using sprout::math::d2_sigmoid;
|
|
} // namespace sprout
|
|
|
|
#endif // #ifndef SPROUT_MATH_SIGMOID_HPP
|