NAME

std::isunordered - std::isunordered

Synopsis

Defined in header <cmath>
bool isunordered( float x, float y ); (1) (since C++11)
(constexpr since C++23)
bool isunordered( double x, double y ); (2) (since C++11)
(constexpr since C++23)
bool isunordered( long double x, long double y ); (3) (since C++11)
(constexpr since C++23)
bool isunordered( Arithmetic x, Arithmetic y ); (4) (since C++11)
(constexpr since C++23)

1-3) Determines if the floating point numbers x and y are unordered, that is, one or
both are NaN and thus cannot be meaningfully compared with each other.
4) A set of overloads or a function template for all combinations of arguments of
arithmetic type not covered by (1-3). If any argument has integral type, it is cast
to double.

Parameters

x - floating point value
y - floating point value

Return value

true if either x or y is NaN, false otherwise

See also

fpclassify categorizes the given floating-point value
(C++11) (function)
isnan checks if the given number is NaN
(C++11) (function)