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DOUBLE COMPLEX FUNCTION ZDOTU(N,ZX,INCX,ZY,INCY)
* .. Scalar Arguments ..
INTEGER INCX,INCY,N
* ..
* .. Array Arguments ..
DOUBLE COMPLEX ZX(*),ZY(*)
* ..
*
* Purpose
* =======
*
* ZDOTU forms the dot product of two vectors.
*
* Further Details
* ===============
*
* jack dongarra, 3/11/78.
* modified 12/3/93, array(1) declarations changed to array(*)
*
* .. Local Scalars ..
DOUBLE COMPLEX ZTEMP
INTEGER I,IX,IY
* ..
ZTEMP = (0.0d0,0.0d0)
ZDOTU = (0.0d0,0.0d0)
IF (N.LE.0) RETURN
IF (INCX.EQ.1 .AND. INCY.EQ.1) GO TO 20
*
* 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 10 I = 1,N
ZTEMP = ZTEMP + ZX(IX)*ZY(IY)
IX = IX + INCX
IY = IY + INCY
10 CONTINUE
ZDOTU = ZTEMP
RETURN
*
* code for both increments equal to 1
*
20 DO 30 I = 1,N
ZTEMP = ZTEMP + ZX(I)*ZY(I)
30 CONTINUE
ZDOTU = ZTEMP
RETURN
END
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