nan, nanf, nanl

Returns a quiet NaN value.

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

Reference

Floating-Point Support

_finite

_fpclass

_isnan