estimator.py 文件源码

def calc_lower_ll(self):
        g = digamma(self.gamma) - digamma(self.gamma.sum(axis=1)[:, np.newaxis])
        N = self._data.nsamples
        psi_d = np.exp(self.log_psi + self._data.log_d[:, :, :, np.newaxis])

        ll = self.ll_offset
        ll += (psi_d.sum(axis=0) * self.log_beta).sum()
        ll += (psi_d.sum(axis=1).sum(axis=1) * g).sum()
        ll += N * (gammaln(self.alpha.sum()) - gammaln(self.alpha).sum()) + (self.alpha * g.sum(axis=0)).sum()
        ll -= (gammaln(self.gamma.sum(axis=1)) - gammaln(self.gamma).sum(axis=1) + (self.gamma * g).sum(axis=1)).sum()
        ll -= (psi_d * self.log_psi).sum()
        return ll