Developer Reference for Intel® oneAPI Math Kernel Library for Fortran
v?InvSqrt
vsInvSqrt vdInvSqrt vmsInvSqrt vmdInvSqrt Computes an inverse square root of vector elements.
Syntax
call vsinvsqrt(n, a, y)
call vsinvsqrti(n, a, inca, y, incy)
call vmsinvsqrt(n, a, y, mode)
call vmsinvsqrti(n, a, inca, y, incy, mode)
call vdinvsqrt(n, a, y)
call vdinvsqrti(n, a, inca, y, incy)
call vmdinvsqrt(n, a, y, mode)
call vmdinvsqrti(n, a, inca, y, incy, mode)
Include Files
mkl_vml.f90
Input Parameters
Name |
Type |
Description |
|---|---|---|
n |
Specifies the number of elements to be calculated. |
|
a |
Fortran 77: DOUBLE PRECISION for vdinvsqrt , vmdinvsqrtFortran 90: REAL , INTENT(IN) for vsinvsqrt , vmsinvsqrtFortran 90: DOUBLE PRECISION , INTENT(IN) for vdinvsqrt , vmdinvsqrt |
Array that specifies the input vector a . |
inca , incy |
INTEGER, INTENT(IN) |
Specifies increments for the elements of a and y . |
mode |
INTEGER(KIND=8) , INTENT(IN) |
Overrides global VM mode setting for this function call. See vmlSetMode (Sets a new mode for VM functions according to the mode parameter and stores the previous VM mode to oldmode.) for possible values and their description. |
Output Parameters
Name |
Type |
Description |
|---|---|---|
y |
Fortran 77: DOUBLE PRECISION for vdinvsqrt , vmdinvsqrtFortran 90: REAL , INTENT(OUT) for vsinvsqrt , vmsinvsqrtFortran 90: DOUBLE PRECISION , INTENT(OUT) for vdinvsqrt , vmdinvsqrt |
Array that specifies 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 |