std::isunordered

 

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HUGE_VALFHUGE_VALHUGE_VALL (C++11)(C++11) INFINITY (C++11) NAN (C++11) math_errhandlingMATH_ERRNOMATH_ERREXCEPT (C++11)	FP_NORMALFP_SUBNORMALFP_ZEROFP_INFINITEFP_NAN (C++11)(C++11)(C++11)(C++11)(C++11)

 

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