Vector length.

float length ( gentype p)

double length (gentype p) // if double extension enabled
half length (gentype p) // if half extension enabled


Returns the length of vector p, i.e., the square root of (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.

If extended with cl_khr_fp64, generic type name gentype may indicate double and double{2|4|8|16} as arguments and return values. If extended with cl_khr_fp16, generic type name gentype may indicate half and half{2|4|8|16} as arguments and return values.


OpenCL Specification

Also see

Geometric Functions

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