Vector length.

float fast_length ( gentype p)


Returns length of vector p computed as:

half_sqrt(p.x2 + p.y2 + ...)


Built-in geometric functions operate component-wise and the description is per-component. The generic type name gentype indicates that the function can take float, float2, or float4 as the type for the arguments.

The built-in geometric functions are implemented using the round to nearest even rounding mode.

The geometric functions can be implemented using contractions such as mad or fma.


OpenCL Specification

Also see

Geometric Functions

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