harmonic butter fly rules like B point should be 0.786 retracement of XA leg And C point should be 0.886 or 0.382 or in between if near values good and is retracement of AB leg and D 1.618 or 2.24 of BC and 1.27 of XA
these are for butter fly for other patterns retracements will vary
disclaimer- this is not any investment call or idea , this just my view and it can go wrong ,this is only for educational purposes trade at your own risk :)