v?Cospi
v?Cospi
Computes the cosine of vector elements multiplied by
π
.Syntax
vsCospi
(
n
,
a
,
y
);
vsCospiI(n, a, inca, y, incy);
vmsCospi
(
n
,
a
,
y
,
mode
);
vmsCospiI(n, a, inca, y, incy, mode);
vdCospi
(
n
,
a
,
y
);
vdCospiI(n, a, inca, y, incy);
vmdCospi
(
n
,
a
,
y
,
mode
);
vmdCospiI(n, a, inca, y, incy, mode);
Include Files
- mkl.h
Input Parameters
Name | Type | Description |
|---|---|---|
n | const MKL_INT | Specifies the number of elements to be calculated. |
a | const float* for vsCospi const float* for vmsCospi const double* for vdCospi const double* for vmdCospi | Pointer to the array containing the input vector a . |
inca , incy | const MKL_INT | Specifies increments for the elements of a and y . |
mode | const MKL_INT64 | Overrides the global VM mode setting for this
function call. See
vmlSetMode
for possible values and their
description. |
Output Parameters
Name | Type | Description |
|---|---|---|
y | float* for vsCospi float* for vmsCospi double* for vdCospi double* for vmdCospi | Pointer to an array containing the output vector y . |
Description
The
v?Cospi
function computes the cosine of vector elements multiplied by π
. For an argument x
, the function computes cos(π
*x
).Argument | Result | VM Error Status | Exception |
|---|---|---|---|
+0 | +1 | ||
-0 | +1 | ||
n + 0.5, for any integer n where n + 0.5 is representable | +0 | ||
± ∞ | QNAN | VML_STATUS_ERRDOM | INVALID |
QNAN | QNAN | ||
SNAN | QNAN | INVALID |
Application Notes
If arguments abs() ≤ 2 ) ≤ 2
a
i
22
for single precision or abs(a
i
43
for double precision, they belong to the fast computational path
: arguments for which VM provides the best possible performance. Avoid arguments with do not belong to the fast computational path in VM High Accuracy (HA) or Low Accuracy (LA) functions. For arguments which do not belong to the fast computational path you can use VM Enhanced Performance (EP) functions, which are fast on the entire function domain. However, these functions provide lower accuracy.