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author | Stanislaw Halik <sthalik@misaki.pl> | 2016-09-18 12:42:15 +0200 |
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committer | Stanislaw Halik <sthalik@misaki.pl> | 2016-11-02 15:12:04 +0100 |
commit | 44861dcbfeee041223c4aac1ee075e92fa4daa01 (patch) | |
tree | 6dfdfd9637846a7aedd71ace97d7d2ad366496d7 /eigen/Eigen/src/Core/MathFunctions.h | |
parent | f3fe458b9e0a29a99a39d47d9a76dc18964b6fec (diff) |
update
Diffstat (limited to 'eigen/Eigen/src/Core/MathFunctions.h')
-rw-r--r-- | eigen/Eigen/src/Core/MathFunctions.h | 779 |
1 files changed, 779 insertions, 0 deletions
diff --git a/eigen/Eigen/src/Core/MathFunctions.h b/eigen/Eigen/src/Core/MathFunctions.h new file mode 100644 index 0000000..dc2c698 --- /dev/null +++ b/eigen/Eigen/src/Core/MathFunctions.h @@ -0,0 +1,779 @@ +// This file is part of Eigen, a lightweight C++ template library +// for linear algebra. +// +// Copyright (C) 2006-2010 Benoit Jacob <jacob.benoit.1@gmail.com> +// +// This Source Code Form is subject to the terms of the Mozilla +// Public License v. 2.0. If a copy of the MPL was not distributed +// with this file, You can obtain one at http://mozilla.org/MPL/2.0/. + +#ifndef EIGEN_MATHFUNCTIONS_H +#define EIGEN_MATHFUNCTIONS_H + +namespace Eigen { + +namespace internal { + +/** \internal \struct global_math_functions_filtering_base + * + * What it does: + * Defines a typedef 'type' as follows: + * - if type T has a member typedef Eigen_BaseClassForSpecializationOfGlobalMathFuncImpl, then + * global_math_functions_filtering_base<T>::type is a typedef for it. + * - otherwise, global_math_functions_filtering_base<T>::type is a typedef for T. + * + * How it's used: + * To allow to defined the global math functions (like sin...) in certain cases, like the Array expressions. + * When you do sin(array1+array2), the object array1+array2 has a complicated expression type, all what you want to know + * is that it inherits ArrayBase. So we implement a partial specialization of sin_impl for ArrayBase<Derived>. + * So we must make sure to use sin_impl<ArrayBase<Derived> > and not sin_impl<Derived>, otherwise our partial specialization + * won't be used. How does sin know that? That's exactly what global_math_functions_filtering_base tells it. + * + * How it's implemented: + * SFINAE in the style of enable_if. Highly susceptible of breaking compilers. With GCC, it sure does work, but if you replace + * the typename dummy by an integer template parameter, it doesn't work anymore! + */ + +template<typename T, typename dummy = void> +struct global_math_functions_filtering_base +{ + typedef T type; +}; + +template<typename T> struct always_void { typedef void type; }; + +template<typename T> +struct global_math_functions_filtering_base + <T, + typename always_void<typename T::Eigen_BaseClassForSpecializationOfGlobalMathFuncImpl>::type + > +{ + typedef typename T::Eigen_BaseClassForSpecializationOfGlobalMathFuncImpl type; +}; + +#define EIGEN_MATHFUNC_IMPL(func, scalar) Eigen::internal::func##_impl<typename Eigen::internal::global_math_functions_filtering_base<scalar>::type> +#define EIGEN_MATHFUNC_RETVAL(func, scalar) typename Eigen::internal::func##_retval<typename Eigen::internal::global_math_functions_filtering_base<scalar>::type>::type + +/**************************************************************************** +* Implementation of real * +****************************************************************************/ + +template<typename Scalar, bool IsComplex = NumTraits<Scalar>::IsComplex> +struct real_default_impl +{ + typedef typename NumTraits<Scalar>::Real RealScalar; + static inline RealScalar run(const Scalar& x) + { + return x; + } +}; + +template<typename Scalar> +struct real_default_impl<Scalar,true> +{ + typedef typename NumTraits<Scalar>::Real RealScalar; + static inline RealScalar run(const Scalar& x) + { + using std::real; + return real(x); + } +}; + +template<typename Scalar> struct real_impl : real_default_impl<Scalar> {}; + +template<typename Scalar> +struct real_retval +{ + typedef typename NumTraits<Scalar>::Real type; +}; + + +/**************************************************************************** +* Implementation of imag * +****************************************************************************/ + +template<typename Scalar, bool IsComplex = NumTraits<Scalar>::IsComplex> +struct imag_default_impl +{ + typedef typename NumTraits<Scalar>::Real RealScalar; + static inline RealScalar run(const Scalar&) + { + return RealScalar(0); + } +}; + +template<typename Scalar> +struct imag_default_impl<Scalar,true> +{ + typedef typename NumTraits<Scalar>::Real RealScalar; + static inline RealScalar run(const Scalar& x) + { + using std::imag; + return imag(x); + } +}; + +template<typename Scalar> struct imag_impl : imag_default_impl<Scalar> {}; + +template<typename Scalar> +struct imag_retval +{ + typedef typename NumTraits<Scalar>::Real type; +}; + +/**************************************************************************** +* Implementation of real_ref * +****************************************************************************/ + +template<typename Scalar> +struct real_ref_impl +{ + typedef typename NumTraits<Scalar>::Real RealScalar; + static inline RealScalar& run(Scalar& x) + { + return reinterpret_cast<RealScalar*>(&x)[0]; + } + static inline const RealScalar& run(const Scalar& x) + { + return reinterpret_cast<const RealScalar*>(&x)[0]; + } +}; + +template<typename Scalar> +struct real_ref_retval +{ + typedef typename NumTraits<Scalar>::Real & type; +}; + +/**************************************************************************** +* Implementation of imag_ref * +****************************************************************************/ + +template<typename Scalar, bool IsComplex> +struct imag_ref_default_impl +{ + typedef typename NumTraits<Scalar>::Real RealScalar; + static inline RealScalar& run(Scalar& x) + { + return reinterpret_cast<RealScalar*>(&x)[1]; + } + static inline const RealScalar& run(const Scalar& x) + { + return reinterpret_cast<RealScalar*>(&x)[1]; + } +}; + +template<typename Scalar> +struct imag_ref_default_impl<Scalar, false> +{ + static inline Scalar run(Scalar&) + { + return Scalar(0); + } + static inline const Scalar run(const Scalar&) + { + return Scalar(0); + } +}; + +template<typename Scalar> +struct imag_ref_impl : imag_ref_default_impl<Scalar, NumTraits<Scalar>::IsComplex> {}; + +template<typename Scalar> +struct imag_ref_retval +{ + typedef typename NumTraits<Scalar>::Real & type; +}; + +/**************************************************************************** +* Implementation of conj * +****************************************************************************/ + +template<typename Scalar, bool IsComplex = NumTraits<Scalar>::IsComplex> +struct conj_impl +{ + static inline Scalar run(const Scalar& x) + { + return x; + } +}; + +template<typename Scalar> +struct conj_impl<Scalar,true> +{ + static inline Scalar run(const Scalar& x) + { + using std::conj; + return conj(x); + } +}; + +template<typename Scalar> +struct conj_retval +{ + typedef Scalar type; +}; + +/**************************************************************************** +* Implementation of abs2 * +****************************************************************************/ + +template<typename Scalar,bool IsComplex> +struct abs2_impl_default +{ + typedef typename NumTraits<Scalar>::Real RealScalar; + static inline RealScalar run(const Scalar& x) + { + return x*x; + } +}; + +template<typename Scalar> +struct abs2_impl_default<Scalar, true> // IsComplex +{ + typedef typename NumTraits<Scalar>::Real RealScalar; + static inline RealScalar run(const Scalar& x) + { + return real(x)*real(x) + imag(x)*imag(x); + } +}; + +template<typename Scalar> +struct abs2_impl +{ + typedef typename NumTraits<Scalar>::Real RealScalar; + static inline RealScalar run(const Scalar& x) + { + return abs2_impl_default<Scalar,NumTraits<Scalar>::IsComplex>::run(x); + } +}; + +template<typename Scalar> +struct abs2_retval +{ + typedef typename NumTraits<Scalar>::Real type; +}; + +/**************************************************************************** +* Implementation of norm1 * +****************************************************************************/ + +template<typename Scalar, bool IsComplex> +struct norm1_default_impl +{ + typedef typename NumTraits<Scalar>::Real RealScalar; + static inline RealScalar run(const Scalar& x) + { + using std::abs; + return abs(real(x)) + abs(imag(x)); + } +}; + +template<typename Scalar> +struct norm1_default_impl<Scalar, false> +{ + static inline Scalar run(const Scalar& x) + { + using std::abs; + return abs(x); + } +}; + +template<typename Scalar> +struct norm1_impl : norm1_default_impl<Scalar, NumTraits<Scalar>::IsComplex> {}; + +template<typename Scalar> +struct norm1_retval +{ + typedef typename NumTraits<Scalar>::Real type; +}; + +/**************************************************************************** +* Implementation of hypot * +****************************************************************************/ + +template<typename Scalar> +struct hypot_impl +{ + typedef typename NumTraits<Scalar>::Real RealScalar; + static inline RealScalar run(const Scalar& x, const Scalar& y) + { + using std::max; + using std::min; + using std::abs; + using std::sqrt; + RealScalar _x = abs(x); + RealScalar _y = abs(y); + RealScalar p = (max)(_x, _y); + if(p==RealScalar(0)) return RealScalar(0); + RealScalar q = (min)(_x, _y); + RealScalar qp = q/p; + return p * sqrt(RealScalar(1) + qp*qp); + } +}; + +template<typename Scalar> +struct hypot_retval +{ + typedef typename NumTraits<Scalar>::Real type; +}; + +/**************************************************************************** +* Implementation of cast * +****************************************************************************/ + +template<typename OldType, typename NewType> +struct cast_impl +{ + static inline NewType run(const OldType& x) + { + return static_cast<NewType>(x); + } +}; + +// here, for once, we're plainly returning NewType: we don't want cast to do weird things. + +template<typename OldType, typename NewType> +inline NewType cast(const OldType& x) +{ + return cast_impl<OldType, NewType>::run(x); +} + +/**************************************************************************** +* Implementation of atanh2 * +****************************************************************************/ + +template<typename Scalar, bool IsInteger> +struct atanh2_default_impl +{ + typedef Scalar retval; + typedef typename NumTraits<Scalar>::Real RealScalar; + static inline Scalar run(const Scalar& x, const Scalar& y) + { + using std::abs; + using std::log; + using std::sqrt; + Scalar z = x / y; + if (y == Scalar(0) || abs(z) > sqrt(NumTraits<RealScalar>::epsilon())) + return RealScalar(0.5) * log((y + x) / (y - x)); + else + return z + z*z*z / RealScalar(3); + } +}; + +template<typename Scalar> +struct atanh2_default_impl<Scalar, true> +{ + static inline Scalar run(const Scalar&, const Scalar&) + { + EIGEN_STATIC_ASSERT_NON_INTEGER(Scalar) + return Scalar(0); + } +}; + +template<typename Scalar> +struct atanh2_impl : atanh2_default_impl<Scalar, NumTraits<Scalar>::IsInteger> {}; + +template<typename Scalar> +struct atanh2_retval +{ + typedef Scalar type; +}; + +/**************************************************************************** +* Implementation of pow * +****************************************************************************/ + +template<typename Scalar, bool IsInteger> +struct pow_default_impl +{ + typedef Scalar retval; + static inline Scalar run(const Scalar& x, const Scalar& y) + { + using std::pow; + return pow(x, y); + } +}; + +template<typename Scalar> +struct pow_default_impl<Scalar, true> +{ + static inline Scalar run(Scalar x, Scalar y) + { + Scalar res(1); + eigen_assert(!NumTraits<Scalar>::IsSigned || y >= 0); + if(y & 1) res *= x; + y >>= 1; + while(y) + { + x *= x; + if(y&1) res *= x; + y >>= 1; + } + return res; + } +}; + +template<typename Scalar> +struct pow_impl : pow_default_impl<Scalar, NumTraits<Scalar>::IsInteger> {}; + +template<typename Scalar> +struct pow_retval +{ + typedef Scalar type; +}; + +/**************************************************************************** +* Implementation of random * +****************************************************************************/ + +template<typename Scalar, + bool IsComplex, + bool IsInteger> +struct random_default_impl {}; + +template<typename Scalar> +struct random_impl : random_default_impl<Scalar, NumTraits<Scalar>::IsComplex, NumTraits<Scalar>::IsInteger> {}; + +template<typename Scalar> +struct random_retval +{ + typedef Scalar type; +}; + +template<typename Scalar> inline EIGEN_MATHFUNC_RETVAL(random, Scalar) random(const Scalar& x, const Scalar& y); +template<typename Scalar> inline EIGEN_MATHFUNC_RETVAL(random, Scalar) random(); + +template<typename Scalar> +struct random_default_impl<Scalar, false, false> +{ + static inline Scalar run(const Scalar& x, const Scalar& y) + { + return x + (y-x) * Scalar(std::rand()) / Scalar(RAND_MAX); + } + static inline Scalar run() + { + return run(Scalar(NumTraits<Scalar>::IsSigned ? -1 : 0), Scalar(1)); + } +}; + +enum { + floor_log2_terminate, + floor_log2_move_up, + floor_log2_move_down, + floor_log2_bogus +}; + +template<unsigned int n, int lower, int upper> struct floor_log2_selector +{ + enum { middle = (lower + upper) / 2, + value = (upper <= lower + 1) ? int(floor_log2_terminate) + : (n < (1 << middle)) ? int(floor_log2_move_down) + : (n==0) ? int(floor_log2_bogus) + : int(floor_log2_move_up) + }; +}; + +template<unsigned int n, + int lower = 0, + int upper = sizeof(unsigned int) * CHAR_BIT - 1, + int selector = floor_log2_selector<n, lower, upper>::value> +struct floor_log2 {}; + +template<unsigned int n, int lower, int upper> +struct floor_log2<n, lower, upper, floor_log2_move_down> +{ + enum { value = floor_log2<n, lower, floor_log2_selector<n, lower, upper>::middle>::value }; +}; + +template<unsigned int n, int lower, int upper> +struct floor_log2<n, lower, upper, floor_log2_move_up> +{ + enum { value = floor_log2<n, floor_log2_selector<n, lower, upper>::middle, upper>::value }; +}; + +template<unsigned int n, int lower, int upper> +struct floor_log2<n, lower, upper, floor_log2_terminate> +{ + enum { value = (n >= ((unsigned int)(1) << (lower+1))) ? lower+1 : lower }; +}; + +template<unsigned int n, int lower, int upper> +struct floor_log2<n, lower, upper, floor_log2_bogus> +{ + // no value, error at compile time +}; + +template<typename Scalar> +struct random_default_impl<Scalar, false, true> +{ + typedef typename NumTraits<Scalar>::NonInteger NonInteger; + + static inline Scalar run(const Scalar& x, const Scalar& y) + { + return x + Scalar((NonInteger(y)-x+1) * std::rand() / (RAND_MAX + NonInteger(1))); + } + + static inline Scalar run() + { +#ifdef EIGEN_MAKING_DOCS + return run(Scalar(NumTraits<Scalar>::IsSigned ? -10 : 0), Scalar(10)); +#else + enum { rand_bits = floor_log2<(unsigned int)(RAND_MAX)+1>::value, + scalar_bits = sizeof(Scalar) * CHAR_BIT, + shift = EIGEN_PLAIN_ENUM_MAX(0, int(rand_bits) - int(scalar_bits)), + offset = NumTraits<Scalar>::IsSigned ? (1 << (EIGEN_PLAIN_ENUM_MIN(rand_bits,scalar_bits)-1)) : 0 + }; + return Scalar((std::rand() >> shift) - offset); +#endif + } +}; + +template<typename Scalar> +struct random_default_impl<Scalar, true, false> +{ + static inline Scalar run(const Scalar& x, const Scalar& y) + { + return Scalar(random(real(x), real(y)), + random(imag(x), imag(y))); + } + static inline Scalar run() + { + typedef typename NumTraits<Scalar>::Real RealScalar; + return Scalar(random<RealScalar>(), random<RealScalar>()); + } +}; + +template<typename Scalar> +inline EIGEN_MATHFUNC_RETVAL(random, Scalar) random(const Scalar& x, const Scalar& y) +{ + return EIGEN_MATHFUNC_IMPL(random, Scalar)::run(x, y); +} + +template<typename Scalar> +inline EIGEN_MATHFUNC_RETVAL(random, Scalar) random() +{ + return EIGEN_MATHFUNC_IMPL(random, Scalar)::run(); +} + +} // end namespace internal + +/**************************************************************************** +* Generic math function * +****************************************************************************/ + +namespace numext { + +template<typename Scalar> +inline EIGEN_MATHFUNC_RETVAL(real, Scalar) real(const Scalar& x) +{ + return EIGEN_MATHFUNC_IMPL(real, Scalar)::run(x); +} + +template<typename Scalar> +inline typename internal::add_const_on_value_type< EIGEN_MATHFUNC_RETVAL(real_ref, Scalar) >::type real_ref(const Scalar& x) +{ + return internal::real_ref_impl<Scalar>::run(x); +} + +template<typename Scalar> +inline EIGEN_MATHFUNC_RETVAL(real_ref, Scalar) real_ref(Scalar& x) +{ + return EIGEN_MATHFUNC_IMPL(real_ref, Scalar)::run(x); +} + +template<typename Scalar> +inline EIGEN_MATHFUNC_RETVAL(imag, Scalar) imag(const Scalar& x) +{ + return EIGEN_MATHFUNC_IMPL(imag, Scalar)::run(x); +} + +template<typename Scalar> +inline typename internal::add_const_on_value_type< EIGEN_MATHFUNC_RETVAL(imag_ref, Scalar) >::type imag_ref(const Scalar& x) +{ + return internal::imag_ref_impl<Scalar>::run(x); +} + +template<typename Scalar> +inline EIGEN_MATHFUNC_RETVAL(imag_ref, Scalar) imag_ref(Scalar& x) +{ + return EIGEN_MATHFUNC_IMPL(imag_ref, Scalar)::run(x); +} + +template<typename Scalar> +inline EIGEN_MATHFUNC_RETVAL(conj, Scalar) conj(const Scalar& x) +{ + return EIGEN_MATHFUNC_IMPL(conj, Scalar)::run(x); +} + +template<typename Scalar> +inline EIGEN_MATHFUNC_RETVAL(abs2, Scalar) abs2(const Scalar& x) +{ + return EIGEN_MATHFUNC_IMPL(abs2, Scalar)::run(x); +} + +template<typename Scalar> +inline EIGEN_MATHFUNC_RETVAL(norm1, Scalar) norm1(const Scalar& x) +{ + return EIGEN_MATHFUNC_IMPL(norm1, Scalar)::run(x); +} + +template<typename Scalar> +inline EIGEN_MATHFUNC_RETVAL(hypot, Scalar) hypot(const Scalar& x, const Scalar& y) +{ + return EIGEN_MATHFUNC_IMPL(hypot, Scalar)::run(x, y); +} + +template<typename Scalar> +inline EIGEN_MATHFUNC_RETVAL(atanh2, Scalar) atanh2(const Scalar& x, const Scalar& y) +{ + return EIGEN_MATHFUNC_IMPL(atanh2, Scalar)::run(x, y); +} + +template<typename Scalar> +inline EIGEN_MATHFUNC_RETVAL(pow, Scalar) pow(const Scalar& x, const Scalar& y) +{ + return EIGEN_MATHFUNC_IMPL(pow, Scalar)::run(x, y); +} + +// std::isfinite is non standard, so let's define our own version, +// even though it is not very efficient. +template<typename T> bool (isfinite)(const T& x) +{ + return x<NumTraits<T>::highest() && x>NumTraits<T>::lowest(); +} + +} // end namespace numext + +namespace internal { + +/**************************************************************************** +* Implementation of fuzzy comparisons * +****************************************************************************/ + +template<typename Scalar, + bool IsComplex, + bool IsInteger> +struct scalar_fuzzy_default_impl {}; + +template<typename Scalar> +struct scalar_fuzzy_default_impl<Scalar, false, false> +{ + typedef typename NumTraits<Scalar>::Real RealScalar; + template<typename OtherScalar> + static inline bool isMuchSmallerThan(const Scalar& x, const OtherScalar& y, const RealScalar& prec) + { + using std::abs; + return abs(x) <= abs(y) * prec; + } + static inline bool isApprox(const Scalar& x, const Scalar& y, const RealScalar& prec) + { + using std::min; + using std::abs; + return abs(x - y) <= (min)(abs(x), abs(y)) * prec; + } + static inline bool isApproxOrLessThan(const Scalar& x, const Scalar& y, const RealScalar& prec) + { + return x <= y || isApprox(x, y, prec); + } +}; + +template<typename Scalar> +struct scalar_fuzzy_default_impl<Scalar, false, true> +{ + typedef typename NumTraits<Scalar>::Real RealScalar; + template<typename OtherScalar> + static inline bool isMuchSmallerThan(const Scalar& x, const Scalar&, const RealScalar&) + { + return x == Scalar(0); + } + static inline bool isApprox(const Scalar& x, const Scalar& y, const RealScalar&) + { + return x == y; + } + static inline bool isApproxOrLessThan(const Scalar& x, const Scalar& y, const RealScalar&) + { + return x <= y; + } +}; + +template<typename Scalar> +struct scalar_fuzzy_default_impl<Scalar, true, false> +{ + typedef typename NumTraits<Scalar>::Real RealScalar; + template<typename OtherScalar> + static inline bool isMuchSmallerThan(const Scalar& x, const OtherScalar& y, const RealScalar& prec) + { + return numext::abs2(x) <= numext::abs2(y) * prec * prec; + } + static inline bool isApprox(const Scalar& x, const Scalar& y, const RealScalar& prec) + { + using std::min; + return numext::abs2(x - y) <= (min)(numext::abs2(x), numext::abs2(y)) * prec * prec; + } +}; + +template<typename Scalar> +struct scalar_fuzzy_impl : scalar_fuzzy_default_impl<Scalar, NumTraits<Scalar>::IsComplex, NumTraits<Scalar>::IsInteger> {}; + +template<typename Scalar, typename OtherScalar> +inline bool isMuchSmallerThan(const Scalar& x, const OtherScalar& y, + const typename NumTraits<Scalar>::Real &precision = NumTraits<Scalar>::dummy_precision()) +{ + return scalar_fuzzy_impl<Scalar>::template isMuchSmallerThan<OtherScalar>(x, y, precision); +} + +template<typename Scalar> +inline bool isApprox(const Scalar& x, const Scalar& y, + const typename NumTraits<Scalar>::Real &precision = NumTraits<Scalar>::dummy_precision()) +{ + return scalar_fuzzy_impl<Scalar>::isApprox(x, y, precision); +} + +template<typename Scalar> +inline bool isApproxOrLessThan(const Scalar& x, const Scalar& y, + const typename NumTraits<Scalar>::Real &precision = NumTraits<Scalar>::dummy_precision()) +{ + return scalar_fuzzy_impl<Scalar>::isApproxOrLessThan(x, y, precision); +} + +/****************************************** +*** The special case of the bool type *** +******************************************/ + +template<> struct random_impl<bool> +{ + static inline bool run() + { + return random<int>(0,1)==0 ? false : true; + } +}; + +template<> struct scalar_fuzzy_impl<bool> +{ + typedef bool RealScalar; + + template<typename OtherScalar> + static inline bool isMuchSmallerThan(const bool& x, const bool&, const bool&) + { + return !x; + } + + static inline bool isApprox(bool x, bool y, bool) + { + return x == y; + } + + static inline bool isApproxOrLessThan(const bool& x, const bool& y, const bool&) + { + return (!x) || y; + } + +}; + + +} // end namespace internal + +} // end namespace Eigen + +#endif // EIGEN_MATHFUNCTIONS_H |