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      real(8) function sdot (n,sx,incx,sy,incy)
!
!     forms the dot product of two vectors.
!     uses unrolled loops for increments equal to one.
!     jack dongarra, linpack, 3/11/78.
!
      use timers

 !    real(8) sx(1),sy(1),stemp
 !    integer i,incx,incy,ix,iy,m,mp1,n
      real(8) sx(n),sy(n)
      integer n
      integer(4) ithandl /0/
      if ( timon ) call timstrt ( "sdot", ithandl )
      sdot = sum ( sx*sy )
!
 !    stemp = 0.0e0
 !    sdot  = 0.0e0
 !    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
 !      stemp = stemp + sx(ix)*sy(iy)
 !      ix = ix + incx
 !      iy = iy + incy
 ! 10 continue
 !    sdot = stemp
 !    goto 9999  !   return
!
!        code for both increments equal to 1
!
!
!        clean-up loop
!
 ! 20 m = mod(n,5)
 !    if( m .eq. 0 ) go to 40
 !    do 30 i = 1,m
 !      stemp = stemp + sx(i)*sy(i)
 ! 30 continue
 !    if( n .lt. 5 ) go to 60
 ! 40 mp1 = m + 1
 !    do 50 i = mp1,n,5
 !      stemp = stemp + sx(i)*sy(i) + sx(i + 1)*sy(i + 1) +
 !   *   sx(i + 2)*sy(i + 2) + sx(i + 3)*sy(i + 3) + sx(i + 4)*sy(i + 4)
 ! 50 continue
 ! 60 sdot = stemp
 9999 if ( timon ) call timstop ( ithandl )
      return
      end