def predict(self):
        """
        Returns
        -------
        proba : ndarray, shape=(n_clusters, )
            The probability of given cluster being label 1.

        """
        if self.w_ is not None:
            sigmoid = lambda t: 1. / (1. + np.exp(-t))
            return sigmoid(np.dot(self.centers, self.w_[:-1]) + self.w_[-1])
        else:
            # TODO the model is not trained
            pass
Returns
        -------
        proba : ndarray, shape=(n_clusters, )
            The probability of given cluster being label 1.