features.py 文件源码

def Kuf(self, kern, Xnew):
        if isinstance(kern, kernels.RBF):
            with decors.params_as_tensors_for(kern):
                Xnew, _ = kern._slice(Xnew, None)
                Zmu, Zlen = kern._slice(self.Z, self.scales)
                idlengthscales = kern.lengthscales + Zlen
                d = self._cust_square_dist(Xnew, Zmu, idlengthscales)
                Kuf = tf.transpose(kern.variance * tf.exp(-d / 2) *
                                   tf.reshape(tf.reduce_prod(kern.lengthscales / idlengthscales, 1),
                                              (1, -1)))
            return Kuf
        else:
            raise NotImplementedError(
                "Multiscale features not implemented for `%s`." % str(type(kern)))