# ilogb

Exponent as an integer value.

## Description

Returns the exponent as an integer value.

## Notes

The vector versions of the math functions operate
component-wise. The description is per-component.

The built-in math functions are not affected by the prevailing rounding mode in the calling
environment, and always return the same value as they would if called with the round to
nearest even rounding mode.

The built-in math functions take scalar or vector arguments. For any specific use of these
function, the actual type has to be the same for all arguments and the return type unless
otherwise specified.

The generic type name gentype is used to indicate that the function can
take float, float2, float3, float4,
float8, float16, double, double2,
double3, double4, double8, or double16
as the type for the arguments.

If extended with cl_khr_fp16,
generic type name gentype may indicate half and
half{2|3|4|8|16} as arguments and return values.

The generic type name gentypef is used to indicate that the function can
take float, float2, float3, float4,
float8, or float16 as the type for the arguments.

The generic type name gentyped is used to indicate that the function can take
double, double2, double3, double4,
double8, or double16 as the type for the arguments.

The following macros shall expand to integer constant expressions whose values are
returned by `ilogb`

(`x`

) if `x`

is zero or NaN, respectively. The value of `FP_ILOGB0`

shall be
either {`INT_MIN`

} or - {`INT_MAX`

}. The value
of `FP_ILOGBNAN`

shall be either {`INT_MAX`

}
or {`INT_MIN`

}.

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