std::numeric_limits::has_quiet_NaN - cppreference.com (original) (raw)

| static const bool has_quiet_NaN; | | (until C++11) | | -------------------------------------- | | ------------- | | static constexpr bool has_quiet_NaN; | | (since C++11) |

The value of std::numeric_limits<T>::has_quiet_NaN is true for all types T capable of representing the special value "Quiet Not-A-Number". This constant is meaningful for all floating-point types and is guaranteed to be true if std::numeric_limits<T>::is_iec559 == true.

[edit] Standard specializations

T value of std::numeric_limits<T>::has_quiet_NaN
/* non-specialized */ false
bool false
char false
signed char false
unsigned char false
wchar_t false
char8_t (since C++20) false
char16_t (since C++11) false
char32_t (since C++11) false
short false
unsigned short false
int false
unsigned int false
long false
unsigned long false
long long (since C++11) false
unsigned long long (since C++11) false
float usually true
double usually true
long double usually true

[edit] See also

| | returns a quiet NaN value of the given floating-point type (public static member function) [edit] | | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | | identifies floating-point types that can represent the special value "positive infinity" (public static member constant) [edit] | | | identifies floating-point types that can represent the special value "signaling not-a-number" (NaN) (public static member constant) [edit] |