std::numeric_limits::round_error

 

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std::numeric_limits

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numeric_limits::is_specialized

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numeric_limits::is_integer

numeric_limits::is_exact

numeric_limits::has_infinity

numeric_limits::has_quiet_NaN

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numeric_limits::has_denorm_loss

numeric_limits::round_style

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numeric_limits::digits10

numeric_limits::max_digits10 (C++11)

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numeric_limits::min_exponent

numeric_limits::min_exponent10

numeric_limits::max_exponent

numeric_limits::max_exponent10

numeric_limits::traps

numeric_limits::tinyness_before

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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();		(until C++11)
static constexpr T round_error();		(since C++11)

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.

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

Exceptions

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

See also

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