# IEEE_IS_NAN

Elemental Module Intrinsic Function (Generic): Returns whether an IEEE value is Not-a-Number (NaN).

## Module

USE, INTRINSIC :: IEEE_ARITHMETIC

result = IEEE_IS_NAN (x)

x | (Input) Must be of type REAL.

## Results

The result type is default logical. The result has the value true if the value of x is NaN; otherwise, false.

## Example

IEEE_IS_NAN (SQRT(-2.0)) has the value true if IEEE_SUPPORT_SQRT (2.0) has the value true.

Parent topic: H to I

## See Also

IEEE_ARITHMETIC Intrinsic Module
IEEE Intrinsic Modules Quick Reference Tables