Determines if the specified value is NAN or QNAN.

ret isnan(x)





[in] The specified value.


Return Value

Returns a value of the same size as the input, with a value set to True if the x parameter is NAN or QNAN. Otherwise, False.

Type Description

Name Template Type Component Type Size
xscalar, vector, or matrix float any
retscalar, vector, or matrix bool as input


Minimum Shader Model

This function is supported in the following shader models.

Shader ModelSupported
Shader Model 2 (DirectX HLSL) and higher shader modelsyes
Shader Model 1 (DirectX HLSL) yes (vs_1_1 only)


See also

Intrinsic Functions (DirectX HLSL)