function ssw_deltat, t0, t1, $ seconds=seconds, minutes=minutes, hours=hours, days=days, loud=loud, $ reference=reference case n_params() of 0: message,"Need input timess..." 1: times=t0 2: times=[anytim(t0(0)),anytim(t1(0))] else: endcase case 1 of keyword_set(seconds): factor=1. keyword_set(minutes): factor=1./60. keyword_set(hours): factor=1./(60.*60.) keyword_set(days): factor=1./(60.*60.*24) else: factor=1.0 endcase case 1 of keyword_set(reference): $ deltat=( anytim(times,/tai) - anytim(reference,/tai) )*factor else:deltat=deriv_arr(anytim(times,/tai))*factor endcase if n_elements(deltat) eq 1 then deltat=deltat(0) return,deltat end