Developer Reference for Intel® oneAPI Math Kernel Library for C

ID 766684
Date 11/07/2023
Public

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Document Table of Contents

v?InvSqrt

Computes an inverse square root of vector elements.

Syntax

vsInvSqrt( n, a, y );

vsInvSqrtI(n, a, inca, y, incy);

vmsInvSqrt( n, a, y, mode );

vmsInvSqrtI(n, a, inca, y, incy, mode);

vdInvSqrt( n, a, y );

vdInvSqrtI(n, a, inca, y, incy);

vmdInvSqrt( n, a, y, mode );

vmdInvSqrtI(n, a, inca, y, incy, mode);

Include Files

  • mkl.h

Input Parameters

Name

Type

Description

n

const MKL_INT

Specifies the number of elements to be calculated.

a

const float* for vsInvSqrt, vmsInvSqrt

const double* for vdInvSqrt, vmdInvSqrt

Pointer to an array that contains the input vector a.

inca, incy

const MKL_INT

Specifies increments for the elements of a and y.

mode

const MKL_INT64

Overrides global VM mode setting for this function call. See vmlSetMode for possible values and their description.

Output Parameters

Name

Type

Description

y

float* for vsInvSqrt, vmsInvSqrt

double* for vdInvSqrt, vmdInvSqrt

Pointer to an array that contains the output vector y.

Description

The v?InvSqrt function computes an inverse square root of vector elements.

Special Values for Real Function v?InvSqrt(x)
Argument Result VM Error Status Exception
X < +0 QNAN VML_STATUS_ERRDOM INVALID
+0 + VML_STATUS_SING ZERODIVIDE
-0 - VML_STATUS_SING ZERODIVIDE
- QNAN VML_STATUS_ERRDOM INVALID
+ +0    
QNAN QNAN    
SNAN QNAN   INVALID