Developer Reference for Intel® oneAPI Math Kernel Library for Fortran

ID 766686
Date 6/24/2024
Public

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Document Table of Contents

v?TGamma

Computes the gamma function of vector elements.

Syntax

call vstgamma( n, a, y )

call vstgammai(n, a, inca, y, incy)

call vmstgamma( n, a, y, mode )

call vmstgammai(n, a, inca, y, incy, mode)

call vdtgamma( n, a, y )

call vdtgammai(n, a, inca, y, incy)

call vmdtgamma( n, a, y, mode )

call vmdtgammai(n, a, inca, y, incy, mode)

Include Files

  • mkl_vml.f90

Input Parameters

Name

Type

Description

n

INTEGER, INTENT(IN)

Specifies the number of elements to be calculated.

a

DOUBLE PRECISION for vdtgamma, vmdtgamma

REAL, INTENT(IN) for vstgamma, vmstgamma

DOUBLE PRECISION, INTENT(IN) for vdtgamma, vmdtgamma

Array that specifies the input vector a.

inca, incy

INTEGER, INTENT(IN)

Specifies increments for the elements of a and y.

mode

INTEGER(KIND=8), INTENT(IN)

Overrides global VM mode setting for this function call. See vmlSetMode for possible values and their description.

Output Parameters

Name

Type

Description

y

DOUBLE PRECISION for vdtgamma, vmdtgamma

REAL, INTENT(OUT) for vstgamma, vmstgamma

DOUBLE PRECISION, INTENT(OUT) for vdtgamma, vmdtgamma

Array that specifies the output vector y.

Description

The v?TGamma function computes the gamma function for elements of the input vector a and writes them to the output vector y. Precision overflow thresholds for the v?TGamma function are beyond the scope of this document. If the result does not meet the target precision, the function raises the OVERFLOW exception and sets the VM Error Status to VML_STATUS_OVERFLOW.

Special Values for Real Function v?TGamma(x)
Argument Result VM Error Status Exception
+0 + VML_STATUS_SING ZERODIVIDE
-0 - VML_STATUS_SING ZERODIVIDE
negative integer QNAN VML_STATUS_ERRDOM INVALID
- QNAN VML_STATUS_ERRDOM INVALID
+ +    
X > overflow + VML_STATUS_OVERFLOW OVERFLOW
QNAN QNAN    
SNAN QNAN   INVALID