Is ExCoupon

Function Is ExCoupon within
Bond with keys Bond Is ExCoupon keys returns true if the given settlement date is on or after the ex coupon date of the accrual period(s) of the referenced bond(s) that includes(include) the date
The financial interpretation is that if a purchased bond settles on , the purchaser will skip (receive) the forthcoming coupon, if the function here returns true (false).

If the settlement date is not explicitly given, it will be set to the bond's settlement date as implied by a trade transaction assumed to occur on the
trade date T₀ (typically today).