def filterCandidates(self, cand):
        """
        Build a HashTree with candidates cand, then count support of these candidates to filter out
        all those that have support not lower than sup_theta
        """
        hashtree = HashTree(cand)
        hashtree.count(self.transactions)
        return hashtree.getNodes(self.sup_theta)

        Build a HashTree with candidates cand, then count support of these candidates to filter out
        all those that have support not lower than sup_theta
        
wordseg/freqitem.py