data_preprocessing.py 文件源码

def _compute_global_pc(self, dataset, session, limit=None):
        """ Compute the Principal Component. """
        _dataset = dataset
        if isinstance(limit, int):
            _dataset = _dataset[:limit]
        d = _dataset
        s0, s1, s2, s3 = d.shape[0], d.shape[1], d.shape[2], d.shape[3]
        flat = np.reshape(d, (s0, s1 * s2 * s3))
        sigma = np.dot(flat.T, flat) / flat.shape[1]
        U, S, V = np.linalg.svd(sigma)
        pc = np.dot(np.dot(U, np.diag(1. / np.sqrt(S + _EPSILON))), U.T)
        self.global_pc.assign(pc, session)
        return pc

    # -----------------------
    #  Persistent Parameters
    # -----------------------