def __iter__(self):
    sdata = self.sorted_data
    if (self.ngroups == 0):
        return
    (starts, ends) = lib.generate_slices(self.slabels, self.ngroups)
    for (start, end) in zip(starts, ends):
        (yield self._chop(sdata, slice(start, end)))
def __iter__(self):
    sdata = self.sorted_data
    if (self.ngroups == 0):
        return
    (starts, ends) = lib.generate_slices(self.slabels, self.ngroups)
    for (start, end) in zip(starts, ends):
        (yield self._chop(sdata, slice(start, end)))