Developer Reference

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

Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.