sdot Function

  function sdot(n,sx,incx,sy,incy)

    !! Routine to compute X*Y where X and Y are vectors
    !! author: Jack Dongarra, Linpack
    !! author: P J Knight, CCFE, Culham Science Centre
    !! n        : input integer : order of the matrices sx, sy
    !! sx(n*incx) : input real array : first vector
    !! incx     : input integer : interval in storage between sx array elements
    !! sy(n*incy) : input real array : second vector
    !! incy     : input integer : interval in storage between sy array elements
    !! This routine performs the dot product of two vectors, i.e.
    !! calculates the sum from i=1 to N, of X(i)*Y(i).
    !!     !
    ! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

    implicit none

    real(dp) :: sdot

    !  Arguments

    integer, intent(in) :: n,incx,incy
    real(dp), dimension(:), intent(in) :: sx
    real(dp), dimension(:), intent(in) :: sy

    !  Local variables

    integer :: ix,i,iy
    real(dp) :: sw

    ! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

    sw = 0.0D0
    ix = 1
    iy = 1
    do i = 1,n
       sw = sw + (sx(ix) * sy(iy))
       ix = ix + incx
       iy = iy + incy
    end do

    sdot = sw

  end function sdot