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nan, nanf, nanl

 

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Returns a quiet NaN value.

Syntax

double nan(  
   const char* input   
);  
float nanf(  
   const char* input   
);  
long double nanl(  
   const char* input   
);  

Parameters

input
A string value.

Return Value

The nan functions return a quiet NaN value.

Remarks

The nan functions return a floating-point value that corresponds to a quiet (non-signalling) NaN. The input value is ignored. For information about how a NaN is represented for output, see printf, _printf_l, wprintf, _wprintf_l.

Requirements

Function C header C++ header
nan, nanf, nanl <math.h> <cmath>

.NET Framework Equivalent

System::Double::NaN

See Also

Floating-Point Support
_finite, _finitef
_fpclass, _fpclassf
isnan, _isnan, _isnanf