FIXME : Add documentation
Type | Intent | Optional | Attributes | Name | ||
---|---|---|---|---|---|---|
real, | intent(in), | dimension (:) | :: | h | ||
real, | intent(in), | dimension (:) | :: | th | ||
real, | intent(out), | dimension (:) | :: | dh |
subroutine get_thgrad (h, th, dh)
implicit none
real, dimension (:), intent (in) :: h, th
real, dimension (:), intent (out) :: dh
integer :: ig, nth
nth = size(th)
do ig = 2, nth-1
dh(ig) = (h(ig+1)-h(ig-1))/(th(ig+1)-th(ig-1))
end do
! note that H_neo is periodic in theta
dh(1) = (h(2)-h(nth))/(2.*(th(2)-th(1)))
dh(nth) = (h(1)-h(nth-1))/(2.*(th(nth)-th(nth-1)))
end subroutine get_thgrad