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std::isnan

From cppreference.com
< cpp‎ | numeric‎ | math
 
 
 
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Defined in header <cmath>
bool isnan( float arg );
(since C++11)
bool isnan( double arg );
(since C++11)
bool isnan( long double arg );
(since C++11)

Determines if the given floating point number arg is not-a-number (NaN).

Contents

[edit] Parameters

arg - floating point value

[edit] Return value

true if arg is NaN, false otherwise

[edit] Notes

In C, isnan is a preprocessor macro, rather than a function.

[edit] See also

categorizes the given floating point value
(function) [edit]
(C++11)
checks if the given number has finite value
(function) [edit]
(C++11)
checks if the given number is infinite
(function) [edit]
(C++11)
checks if the given number is normal
(function) [edit]
checks if two floating-point values are unordered
(function) [edit]
C documentation for isnan