def __init__(self, groups=None):
        super(GroupedRequirements, self).__init__(NamedRequirements)
        self.groups = groups or self.default_groups
        self.filename = None
        self.create_default_groups()
def __probabilities(self, index_cluster, index_point):
        divider = 0.0
        for i in range(self.__amount_clusters):
            divider += self.__pic[i] * self.__gaussians[i][index_point]