Developer Reference for Intel® oneAPI Math Kernel Library for Fortran
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v?InvSqrt
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 |
INTEGER, INTENT(IN) |
Specifies the number of elements to be calculated. |
a |
DOUBLE PRECISION for vdinvsqrt, vmdinvsqrt REAL, INTENT(IN) for vsinvsqrt, vmsinvsqrt 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 for possible values and their description. |
Output Parameters
Name |
Type |
Description |
---|---|---|
y |
DOUBLE PRECISION for vdinvsqrt, vmdinvsqrt REAL, INTENT(OUT) for vsinvsqrt, vmsinvsqrt 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.
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 |