std::numeric_limits::round_error

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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 T round_error()		(pre-C++11 version)
static constexpr T round_error()		(C++11 version)

Returns the largest possible rounding error in ULPs (units in the last place) as defined by ISO 10967, which can vary from 0.5 (rounding to the nearest digit) to 1.0 (rounding to zero or to infinity). It is only meaningful if std::numeric_limits<T>::is_integer == false.

[edit] Return value

T	std::numeric_limits<T>::round_error()
/* 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	0.5F
double	0.5
long double	0.5L

[edit] Exceptions

[edit] See also

round_style	identifies the rounding style used by the type (public static member constant)