hmm.py 文件源码

def _accumulate_sufficient_statistics(self, stats, obs, framelogprob,
                                          posteriors, fwdlattice, bwdlattice):
        super(GaussianHMM, self)._accumulate_sufficient_statistics(
            stats, obs, framelogprob, posteriors, fwdlattice, bwdlattice)

        if 'm' in self.params or 'c' in self.params:
            stats['post'] += posteriors.sum(axis=0)
            stats['obs'] += np.dot(posteriors.T, obs)

        if 'c' in self.params:
            if self.covariance_type in ('spherical', 'diag'):
                stats['obs**2'] += np.dot(posteriors.T, obs ** 2)
            elif self.covariance_type in ('tied', 'full'):
                # posteriors: (nt, nc); obs: (nt, nf); obs: (nt, nf)
                # -> (nc, nf, nf)
                stats['obs*obs.T'] += np.einsum(
                    'ij,ik,il->jkl', posteriors, obs, obs)