def slicesum(self, start, stop=None, axis=0):
        """Slices the histogram along axis, then sums over that slice, returning a d-1 dimensional histogram"""
        return self.slice(start, stop, axis).sum(axis)
def slicesum ( self , start , stop = None , axis = 0 ) : return self . slice ( start , stop , axis ) . sum ( axis )
Slices the histogram along axis, then sums over that slice, returning a d-1 dimensional histogram