SIMD.reciprocalSqrtApproximation

The static SIMD.%type%.reciprocalSqrtApproximation() method returns a new instance with an approximation of the reciprocal value (1 / x) of the square root (Math.sqrt()) of the lane values.

Syntax

SIMD.Float32x4.reciprocalSqrtApproximation(t)
SIMD.Float64x2.reciprocalSqrtApproximation(t)

Parameters

t

An instance of a corresponding SIMD type.

Return value

A new corresponding SIMD data type with the reciprocal (1 / x) of the square root (Math.sqrt()) of the values.

Description

The SIMD.%type%.reciprocalSqrtApproximation() is an approximation of the reciprocal of the square root of the lane values. This means that an estimation of the reciprocal of a number is calculated and that there can be a small amount of error. The Newton-Raphson division, for example, is one of the fast division methods that calculates an estimation. See also this ARM/NEON FAQ article.

Examples

var a = SIMD.Float32x4(1, 2, 3, 4);
SIMD.Float32x4.reciprocalSqrtApproximation(a);
// Float32x4[1, 0.7071067690849304, 0.5773502588272095, 0.5]

var b = SIMD.Float64x2(0, Infinity);
SIMD.Float64x2.reciprocalSqrtApproximation(b);
// Float64x2[Infinity, 0]

Specifications

Specification	Status	Comment
SIMD The definition of 'SIMDConstructor.reciprocalSqrtApproximation' in that specification.	Draft	Initial definition.

Browser compatibility

See also

• SIMD