I have the following doubt: How should the OIS fixed rate be considered in computing principal+interests at the maturity of the swap? I mean, if i.e. the swap lasts 4 day (without w.e. in the middle), and the day count convention is ACT/365, I've found both: P*(1+OIS*4/365) (here) and P*(1+OIS/365)^4 (here)
Thanks!