Developer Reference for Intel® oneAPI Math Kernel Library - C

Developer Reference

  • 0.9
  • 09/09/2020
  • Public Content
Contents

v?Acos

Computes inverse cosine of vector elements.

Syntax

vsAcos
(
n
,
a
,
y
)
;
vsAcosI(n, a, inca, y, incy);
vmsAcos
(
n
,
a
,
y
,
mode
)
;
vmsAcosI(n, a, inca, y, incy, mode);
vdAcos
(
n
,
a
,
y
)
;
vdAcosI(n, a, inca, y, incy);
vmdAcos
(
n
,
a
,
y
,
mode
)
;
vmdAcosI(n, a, inca, y, incy, mode);
vcAcos
(
n
,
a
,
y
)
;
vcAcosI(n, a, inca, y, incy);
vmcAcos
(
n
,
a
,
y
,
mode
)
;
vmcAcosI(n, a, inca, y, incy, mode);
vzAcos
(
n
,
a
,
y
)
;
vzAcosI(n, a, inca, y, incy);
vmzAcos
(
n
,
a
,
y
,
mode
)
;
vmzAcosI(n, a, inca, y, incy, mode);
Include Files
  • mkl.h
Input Parameters
Name
Type
Description
n
const int
Specifies the number of elements to be calculated.
a
const float*
 for
vsAcos
,
vmsAcos
const double*
 for
vdAcos
,
vmdAcos
const MKL_Complex8*
 for
vcAcos
,
vmcAcos
const MKL_Complex16*
 for
vzAcos
,
vmzAcos
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
vsAcos
,
vmsAcos
double*
 for
vdAcos
,
vmdAcos
MKL_Complex8*
 for
vcAcos
,
vmcAcos
MKL_Complex16*
 for
vzAcos
,
vmzAcos
Pointer to an array that contains the output vector
y
.
Description
The
v?Acos
 function computes inverse cosine of vector elements.
Special Values for Real Function
v?Acos(x)
Argument
Result
VM Error Status
Exception
+0
+
π
/2
 
 
-0
+
π
/2
 
 
+1
+0
 
 
-1
+
π
 
 
|X| > 1
QNAN
VML_STATUS_ERRDOM
INVALID
+
∞
QNAN
VML_STATUS_ERRDOM
INVALID
-
∞
QNAN
VML_STATUS_ERRDOM
INVALID
QNAN
QNAN
 
 
SNAN
QNAN
 
INVALID
See Special Value Notations for the conventions used in the table below.
Special Values for Complex Function
v?Acos(z)
RE(z)
i
·
IM(z)
-
∞
 
-X
 
-0
 
+0
 
+X
 
+
∞
 
NAN
 
+i
·
∞
+3
·
π
/4-i
·
∞
+
π
/2-i
·
∞
+
π
/2-i
·
∞
+
π
/2-i
·
∞
+
π
/2-i
·
∞
+
π
/4-i
·
∞
QNAN-i
·
∞
+i
·
Y
+
π
-i
·
∞
+0-i
·
∞
QNAN+i
·
QNAN
+i
·
0
+
π
-i
·
∞
+
π
/2-i
·
0
+
π
/2-i
·
0
+0-i
·
∞
QNAN+i
·
QNAN
-i
·
0
+
π
+i
·
∞
+
π
/2+i
·
0
+
π
/2+i
·
0
+0+i
·
∞
QNAN+i
·
QNAN
-i
·
Y
+
π
+i
·
∞
+0+i
·
∞
QNAN+i
·
QNAN
-i
·
∞
+3
π
/4+i
·
∞
+
π
/2+i
·
∞
+
π
/2+i
·
∞
+
π
/2+i
·
∞
+
π
/2+i
·
∞
+
π
/4+i
·
∞
QNAN+i
·
∞
+i
·
NAN
QNAN+i
·
∞
QNAN+i
·
QNAN
+
π
/2+i
·
QNAN
+
π
/2+i
·
QNAN
QNAN+i
·
QNAN
QNAN+i
·
∞
QNAN+i
·
QNAN
Notes:
  • raises
    INVALID
     exception when real or imaginary part of the argument is
    SNAN
  • Acos(CONJ(z))=CONJ(Acos(z))
    .

Product and Performance Information

1

Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors. These optimizations include SSE2, SSE3, and SSSE3 instruction sets and other optimizations. Intel does not guarantee the availability, functionality, or effectiveness of any optimization on microprocessors not manufactured by Intel. Microprocessor-dependent optimizations in this product are intended for use with Intel microprocessors. Certain optimizations not specific to Intel microarchitecture are reserved for Intel microprocessors. Please refer to the applicable product User and Reference Guides for more information regarding the specific instruction sets covered by this notice.

Notice revision #20110804