def _sample_item(self, **kwargs):
        """Sample an item from the pool according to the instrumental
        distribution
        """
        t = self.t_

        # Update instrumental distribution
        self._calc_inst_pmf()

        if self.record_inst_hist:
            inst_pmf = self._inst_pmf[:,t]
        else:
            inst_pmf = self._inst_pmf

        # Sample label and record weight
        loc, stratum_idx = self.strata.sample(pmf = inst_pmf)
        weight = self.strata.weights_[stratum_idx]/inst_pmf[stratum_idx]

        return loc, weight, {'stratum': stratum_idx}
def _sample_item ( self , ** kwargs ) : t = self . t_ self . _calc_inst_pmf ( ) if self . record_inst_hist : inst_pmf = self . _inst_pmf [ : , t ] else : inst_pmf = self . _inst_pmf loc , stratum_idx = self . strata . sample ( pmf = inst_pmf ) weight = self . strata . weights_ [ stratum_idx ] / inst_pmf [ stratum_idx ] return loc , weight , { 'stratum' : stratum_idx }
Sample an item from the pool according to the instrumental
        distribution