std::numeric_limits::denorm_min

From Cppreference


static T denorm_min()		(pre-C++11 version)

static constexpr T denorm_min()		(C++11 version)

Returns the minimum positive subnormal value of the type T, if std::numeric_limits<T>::has_denorm != std::denorm_absent, otherwise returns std::numeric_limits<T>::min(). Only meaningful for floating-point types.


`T`	std::numeric_limits<T>::denorm_min()

/* non-specialized */	`T();`

bool	false

char	0

signed char	0

unsigned char	0

wchar_t	0

char16_t	0

char32_t	0

short	0

unsigned short	0

int	0

unsigned int	0

long	0

unsigned long	0

long long	0

unsigned long long	0

float	$2 -149$ if std::numeric_limits<float>::is_iec559 == true

double	$2 -1074$ if std::numeric_limits<double>::is_iec559 == true

long double	/* implementation-defined */

[edit] Exceptions

noexcept specification:


noexcept

(C++11 feature)

[edit] Example

Demonstates the underlying bit structure of the denorm_min()

#include <cstdint>
#include <limits>
#include <cassert>
int main()
{
    // the smallest subnormal value has sign bit = 0, exponent = 0
    // and only the least significant bit of the fraction is 1
    uint32_t denorm_bits = 0x0001;
    float denorm_float = reinterpret_cast<float&>(denorm_bits);
    assert(denorm_float == std::numeric_limits<float>::denorm_min());
}

[edit] See also

min [static]

returns the smallest finite value of the given type
(public static member function)

has_denorm

identifies the denormalization style used by the floating-point type
(public static member constant)

lowest [static] (C++11)

returns the lowest finite value of the given type
(public static member function)

std::numeric_limits::denorm_min

From Cppreference

Contents

[edit] Return value

[edit] Exceptions

[edit] Example

[edit] See also