zzdotu.f

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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
*
      SUBROUTINE zzdotu( N, DOTU, X, INCX, Y, INCY ) …
      END