forked from lijiext/lammps
135 lines
2.9 KiB
Fortran
135 lines
2.9 KiB
Fortran
*> \brief \b ZDOTC
|
|
*
|
|
* =========== DOCUMENTATION ===========
|
|
*
|
|
* Online html documentation available at
|
|
* http://www.netlib.org/lapack/explore-html/
|
|
*
|
|
* Definition:
|
|
* ===========
|
|
*
|
|
* COMPLEX*16 FUNCTION ZDOTC(N,ZX,INCX,ZY,INCY)
|
|
*
|
|
* .. Scalar Arguments ..
|
|
* INTEGER INCX,INCY,N
|
|
* ..
|
|
* .. Array Arguments ..
|
|
* COMPLEX*16 ZX(*),ZY(*)
|
|
* ..
|
|
*
|
|
*
|
|
*> \par Purpose:
|
|
* =============
|
|
*>
|
|
*> \verbatim
|
|
*>
|
|
*> ZDOTC forms the dot product of two complex vectors
|
|
*> ZDOTC = X^H * Y
|
|
*>
|
|
*> \endverbatim
|
|
*
|
|
* Arguments:
|
|
* ==========
|
|
*
|
|
*> \param[in] N
|
|
*> \verbatim
|
|
*> N is INTEGER
|
|
*> number of elements in input vector(s)
|
|
*> \endverbatim
|
|
*>
|
|
*> \param[in] ZX
|
|
*> \verbatim
|
|
*> ZX is REAL array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
|
|
*> \endverbatim
|
|
*>
|
|
*> \param[in] INCX
|
|
*> \verbatim
|
|
*> INCX is INTEGER
|
|
*> storage spacing between elements of ZX
|
|
*> \endverbatim
|
|
*>
|
|
*> \param[in] ZY
|
|
*> \verbatim
|
|
*> ZY is REAL array, dimension ( 1 + ( N - 1 )*abs( INCY ) )
|
|
*> \endverbatim
|
|
*>
|
|
*> \param[in] INCY
|
|
*> \verbatim
|
|
*> INCY is INTEGER
|
|
*> storage spacing between elements of ZY
|
|
*> \endverbatim
|
|
*
|
|
* Authors:
|
|
* ========
|
|
*
|
|
*> \author Univ. of Tennessee
|
|
*> \author Univ. of California Berkeley
|
|
*> \author Univ. of Colorado Denver
|
|
*> \author NAG Ltd.
|
|
*
|
|
*> \date December 2016
|
|
*
|
|
*> \ingroup complex16_blas_level1
|
|
*
|
|
*> \par Further Details:
|
|
* =====================
|
|
*>
|
|
*> \verbatim
|
|
*>
|
|
*> jack dongarra, 3/11/78.
|
|
*> modified 12/3/93, array(1) declarations changed to array(*)
|
|
*> \endverbatim
|
|
*>
|
|
* =====================================================================
|
|
COMPLEX*16 FUNCTION ZDOTC(N,ZX,INCX,ZY,INCY)
|
|
*
|
|
* -- Reference BLAS level1 routine (version 3.7.0) --
|
|
* -- Reference BLAS is a software package provided by Univ. of Tennessee, --
|
|
* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
|
|
* December 2016
|
|
*
|
|
* .. Scalar Arguments ..
|
|
INTEGER INCX,INCY,N
|
|
* ..
|
|
* .. Array Arguments ..
|
|
COMPLEX*16 ZX(*),ZY(*)
|
|
* ..
|
|
*
|
|
* =====================================================================
|
|
*
|
|
* .. Local Scalars ..
|
|
COMPLEX*16 ZTEMP
|
|
INTEGER I,IX,IY
|
|
* ..
|
|
* .. Intrinsic Functions ..
|
|
INTRINSIC DCONJG
|
|
* ..
|
|
ZTEMP = (0.0d0,0.0d0)
|
|
ZDOTC = (0.0d0,0.0d0)
|
|
IF (N.LE.0) RETURN
|
|
IF (INCX.EQ.1 .AND. INCY.EQ.1) THEN
|
|
*
|
|
* code for both increments equal to 1
|
|
*
|
|
DO I = 1,N
|
|
ZTEMP = ZTEMP + DCONJG(ZX(I))*ZY(I)
|
|
END DO
|
|
ELSE
|
|
*
|
|
* code for unequal increments or equal increments
|
|
* not equal to 1
|
|
*
|
|
IX = 1
|
|
IY = 1
|
|
IF (INCX.LT.0) IX = (-N+1)*INCX + 1
|
|
IF (INCY.LT.0) IY = (-N+1)*INCY + 1
|
|
DO I = 1,N
|
|
ZTEMP = ZTEMP + DCONJG(ZX(IX))*ZY(IY)
|
|
IX = IX + INCX
|
|
IY = IY + INCY
|
|
END DO
|
|
END IF
|
|
ZDOTC = ZTEMP
|
|
RETURN
|
|
END
|