File: cdotc.f

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      complex function cdotc(n,cx,incx,cy,incy)
c
c     forms the dot product of two vectors, conjugating the first
c     vector.
c     jack dongarra, linpack,  3/11/78.
c     modified 12/3/93, array(1) declarations changed to array(*)
c
      complex cx(*),cy(*),ctemp
      integer i,incx,incy,ix,iy,n
c
      ctemp = (0.0,0.0)
      cdotc = (0.0,0.0)
      if(n.le.0)return
      if(incx.eq.1.and.incy.eq.1)go to 20
c
c        code for unequal increments or equal increments
c          not equal to 1
c
      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
        ctemp = ctemp + conjg(cx(ix))*cy(iy)
        ix = ix + incx
        iy = iy + incy
   10 continue
      cdotc = ctemp
      return
c
c        code for both increments equal to 1
c
   20 do 30 i = 1,n
        ctemp = ctemp + conjg(cx(i))*cy(i)
   30 continue
      cdotc = ctemp
      return
      end