def ydiffs(self): return tslib.unique_deltas(self.fields['Y'].astype('i8'))
def deltas_asi8(self): return tslib.unique_deltas(self.index.asi8)
def mdiffs(self): nmonths = self.fields['Y'] * 12 + self.fields['M'] return tslib.unique_deltas(nmonths.astype('i8'))
def deltas(self): return tslib.unique_deltas(self.values)