Intel® Math Kernel Library 2019 Developer Reference - Fortran
Computes vector a to the scalar power b.
call vspowx( n, a, b, y )
call vmspowx( n, a, b, y, mode )
call vdpowx( n, a, b, y )
call vmdpowx( n, a, b, y, mode )
call vcpowx( n, a, b, y )
call vmcpowx( n, a, b, y, mode )
call vzpowx( n, a, b, y )
call vmzpowx( n, a, b, y, mode )
Name |
Type |
Description |
|---|---|---|
n |
INTEGER, INTENT(IN) |
Number of elements to be calculated. |
a |
DOUBLE PRECISION for vdpowx, vmdpowx COMPLEX for vcpowx, vmcpowx DOUBLE COMPLEX for vzpowx, vmzpowx REAL, INTENT(IN) for vspowx, vmspowx DOUBLE PRECISION, INTENT(IN) for vdpowx, vmdpowx COMPLEX, INTENT(IN) for vcpowx, vmcpowx DOUBLE COMPLEX, INTENT(IN) for vzpowx, vmzpowx |
Array a that specifies the input vector |
| b | DOUBLE PRECISION for vdpowx, vmdpowx COMPLEX for vcpowx, vmcpowx DOUBLE COMPLEX for vzpowx, vmzpowx REAL, INTENT(IN) for vspowx, vmspowx DOUBLE PRECISION, INTENT(IN) for vdpowx, vmdpowx COMPLEX, INTENT(IN) for vcpowx, vmcpowx DOUBLE COMPLEX, INTENT(IN) for vzpowx, vmzpowx |
Scalar value b that is the constant power. |
mode |
INTEGER(KIND=8), INTENT(IN) |
Overrides global VM mode setting for this function call. See vmlSetMode for possible values and their description. |
| Data Type | Threshold Limitations on Input Parameters |
|---|---|
| single precision | abs(a[i]) < ( FLT_MAX )1/b |
| double precision | abs(a[i]) < ( DBL_MAX )1/b |
Precision overflow thresholds for the complex v?Powx function are beyond the scope of this document.
Name |
Type |
Description |
|---|---|---|
y |
DOUBLE PRECISION for vdpowx, vmdpowx COMPLEX for vcpowx, vmcpowx DOUBLE COMPLEX for vzpowx, vmzpowx REAL, INTENT(OUT) for vspowx, vmspowx DOUBLE PRECISION, INTENT(OUT) for vdpowx, vmdpowx COMPLEX, INTENT(OUT) for vcpowx, vmcpowx DOUBLE COMPLEX, INTENT(OUT) for vzpowx, vmzpowx |
Array that specifies the output vector y. |
The v?Powx function computes a to the power b for a vector a and a scalar b.
The real function v(s/d)Powx has certain limitations on the input range of a and b parameters. Specifically, if a[i] is positive, then b may be arbitrary. For negative a[i], the value of b must be an integer (either positive or negative).
The complex function v(c/z)Powx has no input range limitations.
Special values and VM Error Status treatment are the same as for the v?Pow function.