sqrt, rsqrt, half_sqrt, native_sqrt, half_sqrt, native_sqrt

Square root functions.

gentype sqrt ( gentype )
gentype half_sqrt ( gentype x)
gentype native_sqrt ( gentype x)
gentype rsqrt ( gentype )
gentype half_rsqrt ( gentype x)
gentype native_rsqrt ( gentype x)


sqrt computes square root.

half_sqrt computes square root.

native_sqrt computes square root over an implementation-defined range. The maximum error is implementation-defined.

rsqrt computes inverse square root.

half_rsqrt computes inverse square root.

native_rsqrt computes inverse square root over an implementation-defined range. The maximum error is implementation-defined.


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. The generic type name gentype is used to indicate that the function can take float, float2, float3, float4, float8, or float16 as the type for the arguments. For any specific use of these function, the actual type has to be the same for all arguments and the return type.

If extended with cl_khr_fp64, generic type name gentype may indicate double and double{2|3|4|8|16} as arguments and return values. 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.

Functions with the half_ prefix are implemented with a minimum of 10-bits of accuracy i.e. an ULP value less than or equal to 8192 ulp.

Functions with the native_ prefix may map to one or more native device instructions and will typically have better performance compared to the corresponding functions (without the native__ prefix). The accuracy (and in some cases the input range(s)) of these functions is implementation-defined.


OpenCL Specification

Also see

Math Functions

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