Computes the tangent of vector elements multiplied by π.

Syntax

vsTanpi (n, a, y);

vmsTanpi (n, a, y, mode);

vdTanpi (n, a, y);

vmdTanpi (n, a, y, mode);

• mkl.h

Input Parameters

Name

Type

Description

n

const MKL_INT

Specifies the number of elements to be calculated.

a

const float* for vsTanpi

const float* for vmsTanpi

const double* for vdTanpi

const double* for vmdTanpi

Pointer to the array containing the input vector a.

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 vsTanpi

float* for vmsTanpi

double* for vdTanpi

double* for vmdTanpi

Pointer to an array containing the output vector y.

Description

The v?Tanpi function computes the tangent of vector elements multiplied by π. For an argument x, the function computes tan(π*x).

Special values for Real Function v?Tanpi(x)
Argument Result VM Error Status Exception
+0 +1
-0 +1
± QNAN VML_STATUS_ERRDOM INVALID
n, even integer copysign(0.0, n)
n, odd integer copysign(0.0, -n)
n + 0.5, for n even integer and n + 0.5 representable +
n + 0.5, for n odd integer and n + 0.5 representable -
QNAN QNAN
SNAN QNAN   INVALID

The copysign(x, y) function returns the first vector argument x with the sign changed to match that of the second argument y.

Application Notes

If arguments abs(ai) ≤ 2 13 for single precision or abs(ai ) ≤ 2 67 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.