std::numeric_limits<T>::round_error

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static T round_error() throw();		(until C++11)
static constexpr T round_error() noexcept;		(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
char8_t (C++20)	0
char16_t (C++11)	0
char32_t (C++11)	0
short	0
unsigned short	0
int	0
unsigned int	0
long	0
unsigned long	0
long long (C++11)	0
unsigned long long (C++11)	0
float	0.5F
double	0.5
long double	0.5L

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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
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numeric_limits::max_digits10 (C++11)
numeric_limits::radix
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numeric_limits::min_exponent10
numeric_limits::max_exponent
numeric_limits::max_exponent10
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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
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float_denorm_style

std::numeric_limits<T>::round_error

Return value

See also

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