std::numeric_limits::lowest

STD：：数字[医]限制：：最低

static constexpr T lowest()		(since C++11)

返回由数值类型表示的最低限值。T，即有限值x以至于没有其他的有限值y何地y < x这与std::numeric_limits<T>::min()用于浮点类型。仅对有界类型有意义。

返回值

T	std::numeric_limits::lowest()
/* non-specialized */	T(
bool	false
char	CHAR_MIN
signed char	SCHAR_MIN
unsigned char	0
wchar_t	WCHAR_MIN
char16_t	0
char32_t	0
short	SHRT_MIN
unsigned short	0
int	INT_MIN
unsigned int	0
long	LONG_MIN
unsigned long	0
long long	LLONG_MIN
unsigned long long	0
float	-FLT_MAX
double	-DBL_MAX
long double	-LDBL_MAX

注记

对于基本C++浮点类型，第三方浮点类型不适用于%27 s。T可能存在于std::numeric_limits<T>::lowest()!=-std::numeric_limits<T>::max()...

例外

(none)	(until C++11)
noexcept specification: noexcept	(since C++11)

例

演示浮点类型的最小、最大和最低。

二次

#include <limits>
#include <iostream>
int main()
{
 
    std::cout << "std::numeric_limits<T>::min():\n"
              << "\tfloat: " << std::numeric_limits<float>::min()
              << " or " << std::hexfloat << std::numeric_limits<float>::min() << '\n'
              << "\tdouble: " << std::defaultfloat << std::numeric_limits<double>::min()
              << " or " << std::hexfloat << std::numeric_limits<double>::min() << '\n';
    std::cout << "std::numeric_limits<T>::lowest():\n"
              << "\tfloat: " << std::defaultfloat << std::numeric_limits<float>::lowest()
              << " or " << std::hexfloat << std::numeric_limits<float>::lowest() << '\n'
              << "\tdouble: " << std::defaultfloat << std::numeric_limits<double>::lowest()
              << " or " << std::hexfloat << std::numeric_limits<double>::lowest() << '\n';
    std::cout << "std::numeric_limits<T>::max():\n"
              << "\tfloat: " << std::defaultfloat << std::numeric_limits<float>::max()
              << " or " << std::hexfloat << std::numeric_limits<float>::max() << '\n'
              << "\tdouble: " << std::defaultfloat << std::numeric_limits<double>::max()
              << " or " << std::hexfloat << std::numeric_limits<double>::max() << '\n';
}

二次

产出：

二次

std::numeric_limits<T>::min():
        float: 1.17549e-38 or 0x1p-126
        double: 2.22507e-308 or 0x1p-1022
std::numeric_limits<T>::lowest():
        float: -3.40282e+38 or -0x1.fffffep+127
        double: -1.79769e+308 or -0x1.fffffffffffffp+1023
std::numeric_limits<T>::max():
        float: 3.40282e+38 or 0x1.fffffep+127
        double: 1.79769e+308 or 0x1.fffffffffffffp+1023

二次

另见

min static	returns the smallest finite value of the given type (public static member function)
denorm_min static	returns the smallest positive subnormal value of the given floating-point type (public static member function)
max static	returns the largest finite value of the given type (public static member function)

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