llvm-project/libcxx/include/cmath

673 lines
21 KiB
C++

// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef _LIBCPP_CMATH
#define _LIBCPP_CMATH
/*
cmath synopsis
Macros:
HUGE_VAL
HUGE_VALF // C99
HUGE_VALL // C99
INFINITY // C99
NAN // C99
FP_INFINITE // C99
FP_NAN // C99
FP_NORMAL // C99
FP_SUBNORMAL // C99
FP_ZERO // C99
FP_FAST_FMA // C99
FP_FAST_FMAF // C99
FP_FAST_FMAL // C99
FP_ILOGB0 // C99
FP_ILOGBNAN // C99
MATH_ERRNO // C99
MATH_ERREXCEPT // C99
math_errhandling // C99
namespace std
{
Types:
float_t // C99
double_t // C99
// C90
floating_point abs(floating_point x);
floating_point acos (arithmetic x);
float acosf(float x);
long double acosl(long double x);
floating_point asin (arithmetic x);
float asinf(float x);
long double asinl(long double x);
floating_point atan (arithmetic x);
float atanf(float x);
long double atanl(long double x);
floating_point atan2 (arithmetic y, arithmetic x);
float atan2f(float y, float x);
long double atan2l(long double y, long double x);
floating_point ceil (arithmetic x);
float ceilf(float x);
long double ceill(long double x);
floating_point cos (arithmetic x);
float cosf(float x);
long double cosl(long double x);
floating_point cosh (arithmetic x);
float coshf(float x);
long double coshl(long double x);
floating_point exp (arithmetic x);
float expf(float x);
long double expl(long double x);
floating_point fabs (arithmetic x);
float fabsf(float x);
long double fabsl(long double x);
floating_point floor (arithmetic x);
float floorf(float x);
long double floorl(long double x);
floating_point fmod (arithmetic x, arithmetic y);
float fmodf(float x, float y);
long double fmodl(long double x, long double y);
floating_point frexp (arithmetic value, int* exp);
float frexpf(float value, int* exp);
long double frexpl(long double value, int* exp);
floating_point ldexp (arithmetic value, int exp);
float ldexpf(float value, int exp);
long double ldexpl(long double value, int exp);
floating_point log (arithmetic x);
float logf(float x);
long double logl(long double x);
floating_point log10 (arithmetic x);
float log10f(float x);
long double log10l(long double x);
floating_point modf (floating_point value, floating_point* iptr);
float modff(float value, float* iptr);
long double modfl(long double value, long double* iptr);
floating_point pow (arithmetic x, arithmetic y);
float powf(float x, float y);
long double powl(long double x, long double y);
floating_point sin (arithmetic x);
float sinf(float x);
long double sinl(long double x);
floating_point sinh (arithmetic x);
float sinhf(float x);
long double sinhl(long double x);
floating_point sqrt (arithmetic x);
float sqrtf(float x);
long double sqrtl(long double x);
floating_point tan (arithmetic x);
float tanf(float x);
long double tanl(long double x);
floating_point tanh (arithmetic x);
float tanhf(float x);
long double tanhl(long double x);
// C99
bool signbit(arithmetic x);
int fpclassify(arithmetic x);
bool isfinite(arithmetic x);
bool isinf(arithmetic x);
bool isnan(arithmetic x);
bool isnormal(arithmetic x);
bool isgreater(arithmetic x, arithmetic y);
bool isgreaterequal(arithmetic x, arithmetic y);
bool isless(arithmetic x, arithmetic y);
bool islessequal(arithmetic x, arithmetic y);
bool islessgreater(arithmetic x, arithmetic y);
bool isunordered(arithmetic x, arithmetic y);
floating_point acosh (arithmetic x);
float acoshf(float x);
long double acoshl(long double x);
floating_point asinh (arithmetic x);
float asinhf(float x);
long double asinhl(long double x);
floating_point atanh (arithmetic x);
float atanhf(float x);
long double atanhl(long double x);
floating_point cbrt (arithmetic x);
float cbrtf(float x);
long double cbrtl(long double x);
floating_point copysign (arithmetic x, arithmetic y);
float copysignf(float x, float y);
long double copysignl(long double x, long double y);
floating_point erf (arithmetic x);
float erff(float x);
long double erfl(long double x);
floating_point erfc (arithmetic x);
float erfcf(float x);
long double erfcl(long double x);
floating_point exp2 (arithmetic x);
float exp2f(float x);
long double exp2l(long double x);
floating_point expm1 (arithmetic x);
float expm1f(float x);
long double expm1l(long double x);
floating_point fdim (arithmetic x, arithmetic y);
float fdimf(float x, float y);
long double fdiml(long double x, long double y);
floating_point fma (arithmetic x, arithmetic y, arithmetic z);
float fmaf(float x, float y, float z);
long double fmal(long double x, long double y, long double z);
floating_point fmax (arithmetic x, arithmetic y);
float fmaxf(float x, float y);
long double fmaxl(long double x, long double y);
floating_point fmin (arithmetic x, arithmetic y);
float fminf(float x, float y);
long double fminl(long double x, long double y);
floating_point hypot (arithmetic x, arithmetic y);
float hypotf(float x, float y);
long double hypotl(long double x, long double y);
double hypot(double x, double y, double z); // C++17
float hypot(float x, float y, float z); // C++17
long double hypot(long double x, long double y, long double z); // C++17
int ilogb (arithmetic x);
int ilogbf(float x);
int ilogbl(long double x);
floating_point lgamma (arithmetic x);
float lgammaf(float x);
long double lgammal(long double x);
long long llrint (arithmetic x);
long long llrintf(float x);
long long llrintl(long double x);
long long llround (arithmetic x);
long long llroundf(float x);
long long llroundl(long double x);
floating_point log1p (arithmetic x);
float log1pf(float x);
long double log1pl(long double x);
floating_point log2 (arithmetic x);
float log2f(float x);
long double log2l(long double x);
floating_point logb (arithmetic x);
float logbf(float x);
long double logbl(long double x);
long lrint (arithmetic x);
long lrintf(float x);
long lrintl(long double x);
long lround (arithmetic x);
long lroundf(float x);
long lroundl(long double x);
double nan (const char* str);
float nanf(const char* str);
long double nanl(const char* str);
floating_point nearbyint (arithmetic x);
float nearbyintf(float x);
long double nearbyintl(long double x);
floating_point nextafter (arithmetic x, arithmetic y);
float nextafterf(float x, float y);
long double nextafterl(long double x, long double y);
floating_point nexttoward (arithmetic x, long double y);
float nexttowardf(float x, long double y);
long double nexttowardl(long double x, long double y);
floating_point remainder (arithmetic x, arithmetic y);
float remainderf(float x, float y);
long double remainderl(long double x, long double y);
floating_point remquo (arithmetic x, arithmetic y, int* pquo);
float remquof(float x, float y, int* pquo);
long double remquol(long double x, long double y, int* pquo);
floating_point rint (arithmetic x);
float rintf(float x);
long double rintl(long double x);
floating_point round (arithmetic x);
float roundf(float x);
long double roundl(long double x);
floating_point scalbln (arithmetic x, long ex);
float scalblnf(float x, long ex);
long double scalblnl(long double x, long ex);
floating_point scalbn (arithmetic x, int ex);
float scalbnf(float x, int ex);
long double scalbnl(long double x, int ex);
floating_point tgamma (arithmetic x);
float tgammaf(float x);
long double tgammal(long double x);
floating_point trunc (arithmetic x);
float truncf(float x);
long double truncl(long double x);
constexpr float lerp(float a, float b, float t) noexcept; // C++20
constexpr double lerp(double a, double b, double t) noexcept; // C++20
constexpr long double lerp(long double a, long double b, long double t) noexcept; // C++20
} // std
*/
#include <__assert> // all public C++ headers provide the assertion handler
#include <__config>
#include <type_traits>
#include <version>
#include <math.h>
#ifndef _LIBCPP_MATH_H
# error <cmath> tried including <math.h> but didn't find libc++'s <math.h> header. \
This usually means that your header search paths are not configured properly. \
The header search paths should contain the C++ Standard Library headers before \
any C Standard Library, and you are probably using compiler flags that make that \
not be the case.
#endif
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
_LIBCPP_PUSH_MACROS
#include <__undef_macros>
_LIBCPP_BEGIN_NAMESPACE_STD
using ::signbit _LIBCPP_USING_IF_EXISTS;
using ::fpclassify _LIBCPP_USING_IF_EXISTS;
using ::isfinite _LIBCPP_USING_IF_EXISTS;
using ::isinf _LIBCPP_USING_IF_EXISTS;
using ::isnan _LIBCPP_USING_IF_EXISTS;
using ::isnormal _LIBCPP_USING_IF_EXISTS;
using ::isgreater _LIBCPP_USING_IF_EXISTS;
using ::isgreaterequal _LIBCPP_USING_IF_EXISTS;
using ::isless _LIBCPP_USING_IF_EXISTS;
using ::islessequal _LIBCPP_USING_IF_EXISTS;
using ::islessgreater _LIBCPP_USING_IF_EXISTS;
using ::isunordered _LIBCPP_USING_IF_EXISTS;
using ::isunordered _LIBCPP_USING_IF_EXISTS;
using ::float_t _LIBCPP_USING_IF_EXISTS;
using ::double_t _LIBCPP_USING_IF_EXISTS;
using ::abs _LIBCPP_USING_IF_EXISTS;
using ::acos _LIBCPP_USING_IF_EXISTS;
using ::acosf _LIBCPP_USING_IF_EXISTS;
using ::asin _LIBCPP_USING_IF_EXISTS;
using ::asinf _LIBCPP_USING_IF_EXISTS;
using ::atan _LIBCPP_USING_IF_EXISTS;
using ::atanf _LIBCPP_USING_IF_EXISTS;
using ::atan2 _LIBCPP_USING_IF_EXISTS;
using ::atan2f _LIBCPP_USING_IF_EXISTS;
using ::ceil _LIBCPP_USING_IF_EXISTS;
using ::ceilf _LIBCPP_USING_IF_EXISTS;
using ::cos _LIBCPP_USING_IF_EXISTS;
using ::cosf _LIBCPP_USING_IF_EXISTS;
using ::cosh _LIBCPP_USING_IF_EXISTS;
using ::coshf _LIBCPP_USING_IF_EXISTS;
using ::exp _LIBCPP_USING_IF_EXISTS;
using ::expf _LIBCPP_USING_IF_EXISTS;
using ::fabs _LIBCPP_USING_IF_EXISTS;
using ::fabsf _LIBCPP_USING_IF_EXISTS;
using ::floor _LIBCPP_USING_IF_EXISTS;
using ::floorf _LIBCPP_USING_IF_EXISTS;
using ::fmod _LIBCPP_USING_IF_EXISTS;
using ::fmodf _LIBCPP_USING_IF_EXISTS;
using ::frexp _LIBCPP_USING_IF_EXISTS;
using ::frexpf _LIBCPP_USING_IF_EXISTS;
using ::ldexp _LIBCPP_USING_IF_EXISTS;
using ::ldexpf _LIBCPP_USING_IF_EXISTS;
using ::log _LIBCPP_USING_IF_EXISTS;
using ::logf _LIBCPP_USING_IF_EXISTS;
using ::log10 _LIBCPP_USING_IF_EXISTS;
using ::log10f _LIBCPP_USING_IF_EXISTS;
using ::modf _LIBCPP_USING_IF_EXISTS;
using ::modff _LIBCPP_USING_IF_EXISTS;
using ::pow _LIBCPP_USING_IF_EXISTS;
using ::powf _LIBCPP_USING_IF_EXISTS;
using ::sin _LIBCPP_USING_IF_EXISTS;
using ::sinf _LIBCPP_USING_IF_EXISTS;
using ::sinh _LIBCPP_USING_IF_EXISTS;
using ::sinhf _LIBCPP_USING_IF_EXISTS;
using ::sqrt _LIBCPP_USING_IF_EXISTS;
using ::sqrtf _LIBCPP_USING_IF_EXISTS;
using ::tan _LIBCPP_USING_IF_EXISTS;
using ::tanf _LIBCPP_USING_IF_EXISTS;
using ::tanh _LIBCPP_USING_IF_EXISTS;
using ::tanhf _LIBCPP_USING_IF_EXISTS;
using ::acosh _LIBCPP_USING_IF_EXISTS;
using ::acoshf _LIBCPP_USING_IF_EXISTS;
using ::asinh _LIBCPP_USING_IF_EXISTS;
using ::asinhf _LIBCPP_USING_IF_EXISTS;
using ::atanh _LIBCPP_USING_IF_EXISTS;
using ::atanhf _LIBCPP_USING_IF_EXISTS;
using ::cbrt _LIBCPP_USING_IF_EXISTS;
using ::cbrtf _LIBCPP_USING_IF_EXISTS;
using ::copysign _LIBCPP_USING_IF_EXISTS;
using ::copysignf _LIBCPP_USING_IF_EXISTS;
using ::erf _LIBCPP_USING_IF_EXISTS;
using ::erff _LIBCPP_USING_IF_EXISTS;
using ::erfc _LIBCPP_USING_IF_EXISTS;
using ::erfcf _LIBCPP_USING_IF_EXISTS;
using ::exp2 _LIBCPP_USING_IF_EXISTS;
using ::exp2f _LIBCPP_USING_IF_EXISTS;
using ::expm1 _LIBCPP_USING_IF_EXISTS;
using ::expm1f _LIBCPP_USING_IF_EXISTS;
using ::fdim _LIBCPP_USING_IF_EXISTS;
using ::fdimf _LIBCPP_USING_IF_EXISTS;
using ::fmaf _LIBCPP_USING_IF_EXISTS;
using ::fma _LIBCPP_USING_IF_EXISTS;
using ::fmax _LIBCPP_USING_IF_EXISTS;
using ::fmaxf _LIBCPP_USING_IF_EXISTS;
using ::fmin _LIBCPP_USING_IF_EXISTS;
using ::fminf _LIBCPP_USING_IF_EXISTS;
using ::hypot _LIBCPP_USING_IF_EXISTS;
using ::hypotf _LIBCPP_USING_IF_EXISTS;
using ::ilogb _LIBCPP_USING_IF_EXISTS;
using ::ilogbf _LIBCPP_USING_IF_EXISTS;
using ::lgamma _LIBCPP_USING_IF_EXISTS;
using ::lgammaf _LIBCPP_USING_IF_EXISTS;
using ::llrint _LIBCPP_USING_IF_EXISTS;
using ::llrintf _LIBCPP_USING_IF_EXISTS;
using ::llround _LIBCPP_USING_IF_EXISTS;
using ::llroundf _LIBCPP_USING_IF_EXISTS;
using ::log1p _LIBCPP_USING_IF_EXISTS;
using ::log1pf _LIBCPP_USING_IF_EXISTS;
using ::log2 _LIBCPP_USING_IF_EXISTS;
using ::log2f _LIBCPP_USING_IF_EXISTS;
using ::logb _LIBCPP_USING_IF_EXISTS;
using ::logbf _LIBCPP_USING_IF_EXISTS;
using ::lrint _LIBCPP_USING_IF_EXISTS;
using ::lrintf _LIBCPP_USING_IF_EXISTS;
using ::lround _LIBCPP_USING_IF_EXISTS;
using ::lroundf _LIBCPP_USING_IF_EXISTS;
using ::nan _LIBCPP_USING_IF_EXISTS;
using ::nanf _LIBCPP_USING_IF_EXISTS;
using ::nearbyint _LIBCPP_USING_IF_EXISTS;
using ::nearbyintf _LIBCPP_USING_IF_EXISTS;
using ::nextafter _LIBCPP_USING_IF_EXISTS;
using ::nextafterf _LIBCPP_USING_IF_EXISTS;
using ::nexttoward _LIBCPP_USING_IF_EXISTS;
using ::nexttowardf _LIBCPP_USING_IF_EXISTS;
using ::remainder _LIBCPP_USING_IF_EXISTS;
using ::remainderf _LIBCPP_USING_IF_EXISTS;
using ::remquo _LIBCPP_USING_IF_EXISTS;
using ::remquof _LIBCPP_USING_IF_EXISTS;
using ::rint _LIBCPP_USING_IF_EXISTS;
using ::rintf _LIBCPP_USING_IF_EXISTS;
using ::round _LIBCPP_USING_IF_EXISTS;
using ::roundf _LIBCPP_USING_IF_EXISTS;
using ::scalbln _LIBCPP_USING_IF_EXISTS;
using ::scalblnf _LIBCPP_USING_IF_EXISTS;
using ::scalbn _LIBCPP_USING_IF_EXISTS;
using ::scalbnf _LIBCPP_USING_IF_EXISTS;
using ::tgamma _LIBCPP_USING_IF_EXISTS;
using ::tgammaf _LIBCPP_USING_IF_EXISTS;
using ::trunc _LIBCPP_USING_IF_EXISTS;
using ::truncf _LIBCPP_USING_IF_EXISTS;
using ::acosl _LIBCPP_USING_IF_EXISTS;
using ::asinl _LIBCPP_USING_IF_EXISTS;
using ::atanl _LIBCPP_USING_IF_EXISTS;
using ::atan2l _LIBCPP_USING_IF_EXISTS;
using ::ceill _LIBCPP_USING_IF_EXISTS;
using ::cosl _LIBCPP_USING_IF_EXISTS;
using ::coshl _LIBCPP_USING_IF_EXISTS;
using ::expl _LIBCPP_USING_IF_EXISTS;
using ::fabsl _LIBCPP_USING_IF_EXISTS;
using ::floorl _LIBCPP_USING_IF_EXISTS;
using ::fmodl _LIBCPP_USING_IF_EXISTS;
using ::frexpl _LIBCPP_USING_IF_EXISTS;
using ::ldexpl _LIBCPP_USING_IF_EXISTS;
using ::logl _LIBCPP_USING_IF_EXISTS;
using ::log10l _LIBCPP_USING_IF_EXISTS;
using ::modfl _LIBCPP_USING_IF_EXISTS;
using ::powl _LIBCPP_USING_IF_EXISTS;
using ::sinl _LIBCPP_USING_IF_EXISTS;
using ::sinhl _LIBCPP_USING_IF_EXISTS;
using ::sqrtl _LIBCPP_USING_IF_EXISTS;
using ::tanl _LIBCPP_USING_IF_EXISTS;
using ::tanhl _LIBCPP_USING_IF_EXISTS;
using ::acoshl _LIBCPP_USING_IF_EXISTS;
using ::asinhl _LIBCPP_USING_IF_EXISTS;
using ::atanhl _LIBCPP_USING_IF_EXISTS;
using ::cbrtl _LIBCPP_USING_IF_EXISTS;
using ::copysignl _LIBCPP_USING_IF_EXISTS;
using ::erfl _LIBCPP_USING_IF_EXISTS;
using ::erfcl _LIBCPP_USING_IF_EXISTS;
using ::exp2l _LIBCPP_USING_IF_EXISTS;
using ::expm1l _LIBCPP_USING_IF_EXISTS;
using ::fdiml _LIBCPP_USING_IF_EXISTS;
using ::fmal _LIBCPP_USING_IF_EXISTS;
using ::fmaxl _LIBCPP_USING_IF_EXISTS;
using ::fminl _LIBCPP_USING_IF_EXISTS;
using ::hypotl _LIBCPP_USING_IF_EXISTS;
using ::ilogbl _LIBCPP_USING_IF_EXISTS;
using ::lgammal _LIBCPP_USING_IF_EXISTS;
using ::llrintl _LIBCPP_USING_IF_EXISTS;
using ::llroundl _LIBCPP_USING_IF_EXISTS;
using ::log1pl _LIBCPP_USING_IF_EXISTS;
using ::log2l _LIBCPP_USING_IF_EXISTS;
using ::logbl _LIBCPP_USING_IF_EXISTS;
using ::lrintl _LIBCPP_USING_IF_EXISTS;
using ::lroundl _LIBCPP_USING_IF_EXISTS;
using ::nanl _LIBCPP_USING_IF_EXISTS;
using ::nearbyintl _LIBCPP_USING_IF_EXISTS;
using ::nextafterl _LIBCPP_USING_IF_EXISTS;
using ::nexttowardl _LIBCPP_USING_IF_EXISTS;
using ::remainderl _LIBCPP_USING_IF_EXISTS;
using ::remquol _LIBCPP_USING_IF_EXISTS;
using ::rintl _LIBCPP_USING_IF_EXISTS;
using ::roundl _LIBCPP_USING_IF_EXISTS;
using ::scalblnl _LIBCPP_USING_IF_EXISTS;
using ::scalbnl _LIBCPP_USING_IF_EXISTS;
using ::tgammal _LIBCPP_USING_IF_EXISTS;
using ::truncl _LIBCPP_USING_IF_EXISTS;
#if _LIBCPP_STD_VER > 14
inline _LIBCPP_INLINE_VISIBILITY float hypot( float __x, float __y, float __z ) { return sqrt(__x*__x + __y*__y + __z*__z); }
inline _LIBCPP_INLINE_VISIBILITY double hypot( double __x, double __y, double __z ) { return sqrt(__x*__x + __y*__y + __z*__z); }
inline _LIBCPP_INLINE_VISIBILITY long double hypot( long double __x, long double __y, long double __z ) { return sqrt(__x*__x + __y*__y + __z*__z); }
template <class _A1, class _A2, class _A3>
inline _LIBCPP_INLINE_VISIBILITY
typename enable_if_t
<
is_arithmetic<_A1>::value &&
is_arithmetic<_A2>::value &&
is_arithmetic<_A3>::value,
__promote<_A1, _A2, _A3>
>::type
hypot(_A1 __lcpp_x, _A2 __lcpp_y, _A3 __lcpp_z) _NOEXCEPT
{
typedef typename __promote<_A1, _A2, _A3>::type __result_type;
static_assert((!(is_same<_A1, __result_type>::value &&
is_same<_A2, __result_type>::value &&
is_same<_A3, __result_type>::value)), "");
return hypot((__result_type)__lcpp_x, (__result_type)__lcpp_y, (__result_type)__lcpp_z);
}
#endif
template <class _A1>
_LIBCPP_INLINE_VISIBILITY
_LIBCPP_CONSTEXPR typename enable_if<is_floating_point<_A1>::value, bool>::type
__libcpp_isnan_or_builtin(_A1 __lcpp_x) _NOEXCEPT
{
#if __has_builtin(__builtin_isnan)
return __builtin_isnan(__lcpp_x);
#else
return isnan(__lcpp_x);
#endif
}
template <class _A1>
_LIBCPP_INLINE_VISIBILITY
_LIBCPP_CONSTEXPR typename enable_if<!is_floating_point<_A1>::value, bool>::type
__libcpp_isnan_or_builtin(_A1 __lcpp_x) _NOEXCEPT
{
return isnan(__lcpp_x);
}
template <class _A1>
_LIBCPP_INLINE_VISIBILITY
_LIBCPP_CONSTEXPR typename enable_if<is_floating_point<_A1>::value, bool>::type
__libcpp_isinf_or_builtin(_A1 __lcpp_x) _NOEXCEPT
{
#if __has_builtin(__builtin_isinf)
return __builtin_isinf(__lcpp_x);
#else
return isinf(__lcpp_x);
#endif
}
template <class _A1>
_LIBCPP_INLINE_VISIBILITY
_LIBCPP_CONSTEXPR typename enable_if<!is_floating_point<_A1>::value, bool>::type
__libcpp_isinf_or_builtin(_A1 __lcpp_x) _NOEXCEPT
{
return isinf(__lcpp_x);
}
template <class _A1>
_LIBCPP_INLINE_VISIBILITY
_LIBCPP_CONSTEXPR typename enable_if<is_floating_point<_A1>::value, bool>::type
__libcpp_isfinite_or_builtin(_A1 __lcpp_x) _NOEXCEPT
{
#if __has_builtin(__builtin_isfinite)
return __builtin_isfinite(__lcpp_x);
#else
return isfinite(__lcpp_x);
#endif
}
template <class _A1>
_LIBCPP_INLINE_VISIBILITY
_LIBCPP_CONSTEXPR typename enable_if<!is_floating_point<_A1>::value, bool>::type
__libcpp_isfinite_or_builtin(_A1 __lcpp_x) _NOEXCEPT
{
return isfinite(__lcpp_x);
}
#if _LIBCPP_STD_VER > 17
template <typename _Fp>
_LIBCPP_HIDE_FROM_ABI constexpr
_Fp __lerp(_Fp __a, _Fp __b, _Fp __t) noexcept {
if ((__a <= 0 && __b >= 0) || (__a >= 0 && __b <= 0))
return __t * __b + (1 - __t) * __a;
if (__t == 1) return __b;
const _Fp __x = __a + __t * (__b - __a);
if ((__t > 1) == (__b > __a))
return __b < __x ? __x : __b;
else
return __x < __b ? __x : __b;
}
_LIBCPP_HIDE_FROM_ABI constexpr float
lerp(float __a, float __b, float __t) _NOEXCEPT { return __lerp(__a, __b, __t); }
_LIBCPP_HIDE_FROM_ABI constexpr double
lerp(double __a, double __b, double __t) _NOEXCEPT { return __lerp(__a, __b, __t); }
_LIBCPP_HIDE_FROM_ABI constexpr long double
lerp(long double __a, long double __b, long double __t) _NOEXCEPT { return __lerp(__a, __b, __t); }
template <class _A1, class _A2, class _A3>
inline _LIBCPP_HIDE_FROM_ABI
constexpr typename enable_if_t
<
is_arithmetic<_A1>::value &&
is_arithmetic<_A2>::value &&
is_arithmetic<_A3>::value,
__promote<_A1, _A2, _A3>
>::type
lerp(_A1 __a, _A2 __b, _A3 __t) noexcept
{
typedef typename __promote<_A1, _A2, _A3>::type __result_type;
static_assert(!(_IsSame<_A1, __result_type>::value &&
_IsSame<_A2, __result_type>::value &&
_IsSame<_A3, __result_type>::value));
return __lerp((__result_type)__a, (__result_type)__b, (__result_type)__t);
}
#endif // _LIBCPP_STD_VER > 17
_LIBCPP_END_NAMESPACE_STD
_LIBCPP_POP_MACROS
#endif // _LIBCPP_CMATH