! delta_function.jnl
! Description: Defines a Dirac delta function at central point in time

! Programmed by E. D. Cokelet, NOAA/PMEL, 30 Nov 1999

! Usage:  go delta_function central_point_index_number output_function_name
! The output delta function's time range will be 2*(central_point_index_number)

can mode verify

define axis/units=hours/t=1:`2*$1`:1 t_ax_delta
let tim_delta = t[gt=t_ax_delta]
define grid/t=t_ax_delta grid_delta

let delta_delta = if tim_delta eq `$1` then 1 else 0
let $2 = delta_delta[g=grid_delta]