std::numeric_limits::has_denorm_loss

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std::numeric_limits
Static constants numeric_limits::is_specialized numeric_limits::is_signed numeric_limits::is_integer numeric_limits::is_exact numeric_limits::has_infinity numeric_limits::has_quiet_NaN numeric_limits::has_signaling_NaN numeric_limits::has_denorm numeric_limits::has_denorm_loss numeric_limits::round_style numeric_limits::is_iec559 numeric_limits::is_bounded numeric_limits::is_modulo numeric_limits::digits numeric_limits::digits10 numeric_limits::max_digits10 (C++11) numeric_limits::radix numeric_limits::min_exponent numeric_limits::min_exponent10 numeric_limits::max_exponent numeric_limits::max_exponent10 numeric_limits::traps numeric_limits::tinyness_before Static member functions numeric_limits::min numeric_limits::lowest (C++11) numeric_limits::max numeric_limits::epsilon numeric_limits::round_error numeric_limits::infinity numeric_limits::quiet_NaN numeric_limits::signaling_NaN numeric_limits::denorm_min Helper types float_round_style float_denorm_style

static const bool has_denorm_loss		(pre-C++11 version)
static constexpr bool has_denorm_loss		(C++11 version)

The value of std::numeric_limits<T>::has_denorm_loss is true for all floating-point types T capable of distinguishing loss of precision due to denormalization from other causes of inexact result.

Contents 1 Standard specializations 2 Notes 3 Example 4 See also

[edit] Standard specializations

T	value of std::numeric_limits<T>::has_denorm_loss
/* non-specialized */	false
bool	false
char	false
signed char	false
unsigned char	false
wchar_t	false
char16_t	false
char32_t	false
short	false
unsigned short	false
int	false
unsigned int	false
long	false
unsigned long	false
long long	false
unsigned long long	false
float	implementation-defined
double	implementation-defined
long double	implementation-defined

[edit] Notes

Standard-compliant IEE 754 floating-point implementations may detect the floating-point underflow at three predefined moments:

1) after computation of a result with absolute value smaller than std::numeric_limits<T>::min(), such implementation detects tinyness before rounding.

2) after rounding of the result to std::numeric_limits<T>::digits bits, if the result is tiny, such implementation detects tinyness after rounding.

3) if the conversion of the rounded tiny result to subnormal form resulted in the loss of precision, such implementation detects denorm loss.

[edit] Example

This section is incomplete

[edit] See also

tinyness_before	identifies floating-point types that detect tinyness before rounding (public static member constant)
has_denorm	identifies the denormalization style used by the floating-point type (public static member constant)