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SUBROUTINE ZZDOTU( N, DOTU, X, INCX, Y, INCY )
*
* -- ScaLAPACK tools routine (version 1.7) --
* University of Tennessee, Knoxville, Oak Ridge National Laboratory,
* and University of California, Berkeley.
* May 1, 1997
*
* .. Scalar Arguments ..
INTEGER INCX, INCY, N
COMPLEX*16 DOTU
* ..
* .. Array Arguments ..
COMPLEX*16 X( * ), Y( * )
* ..
*
* Purpose
* =======
*
* ZZDOTU is a simple FORTRAN wrapper around the BLAS function
* ZDOTU returning the result in the parameter list instead.
*
* =====================================================================
*
* .. Local Scalars ..
COMPLEX*16 ZTEMP
INTEGER I,IX,IY
* ..
* .. Executable Statements ..
*
ZTEMP = (0.0d0,0.0d0)
DOTU = (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 + X(I)*Y(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 + X(IX)*Y(IY)
IX = IX + INCX
IY = IY + INCY
END DO
END IF
DOTU = ZTEMP
*
RETURN
*
* End of ZZDOTU
*
END
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