spcof1 Subroutine

  subroutine spcof1(x,avh,y,dy,n,p,q,a,c,ic,u,v)
!
! calculates coefficients of a cubic smoothing spline from
! parameters calculated by subroutine spfit1.
!
!---specifications for arguments---
    integer, intent(in) :: ic,n
    real, dimension (:), intent(in) :: x, y, dy
    real, dimension (:), intent(out) :: a
    real, dimension (ic, 3), intent(out) :: c
    real, dimension (0:n+1), intent(in out) :: u
    real, dimension (0:n+1), intent(in) :: v
    real, intent(in) :: p, q, avh
!
!---specifications for local variables---
    integer :: i
    real :: h,qh
!
!---calculate a---
    qh = q/ (avh*avh)
    do i = 1,n
       a(i) = y(i) - p*dy(i)*v(i)
       u(i) = qh*u(i)
    end do
!
!---calculate c---
    do i = 1,n - 1
       h = x(i+1) - x(i)
       c(i,3) = (u(i+1)-u(i))/ (3.0d0*h)
       c(i,1) = (a(i+1)-a(i))/h - (h*c(i,3)+u(i))*h
       c(i,2) = u(i)
    end do
  end subroutine spcof1