MathF.ReciprocalSqrtEstimate(Single) Method

Definition

Namespace:

System

Assembly:

System.Runtime.dll

Source:

MathF.cs

Returns an estimate of the reciprocal square root of a specified number.

public:
 static float ReciprocalSqrtEstimate(float x);

public static float ReciprocalSqrtEstimate (float x);

static member ReciprocalSqrtEstimate : single -> single

Public Shared Function ReciprocalSqrtEstimate (x As Single) As Single

Parameters

x

Single

The number whose reciprocal square root is to be estimated.

Returns

Single

An estimate of the reciprocal square root x.

Remarks

On x86/x64 hardware this may use the RSQRTSS instruction which has a maximum relative error of 1.5 * 2^-12.

On ARM64 hardware this may use the FRSQRTE instruction which performs a single Newton-Raphson iteration.

On hardware without specialized support, this may just return 1.0 / Sqrt(x).