Exemplo n.º 1
0
    def setup_base_gps(self):
        self.base_gps = []  # one per dataset
        self.deep_gps = []  # all but the first dataset
        self.parent_gps = []
        for i in range(self.num_datasets):
            z = self.Z[0][i]
            k = self.kernels[0][i]
            sig = self.noise_sigmas[0][i]

            gp = MR_SVGP(z, k, sig)
            self.base_gps.append(gp)

            if i > 0:
                z = self.Z[1][i - 1]
                k = self.kernels[1][i - 1]
                sig = self.noise_sigmas[1][i - 1]

                dgp = MR_SVGP(z, k, sig)
                self.deep_gps.append(dgp)

        if self.parent_mixtures:
            for i in range(len(self.parent_mixtures)):
                z = self.Z[2][i]
                k = self.kernels[2][i]
                sig = self.noise_sigmas[2][i]

                gp = MR_SVGP(z, k, sig)

                self.parent_gps.append(gp)

        self.base_gps = ParamList(self.base_gps)
        self.deep_gps = ParamList(self.deep_gps)
        self.parent_gps = ParamList(self.parent_gps)
Exemplo n.º 2
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    def __init__(self,
                 kern,
                 Z,
                 mean_function,
                 num_nodes,
                 dim_per_in,
                 dim_per_out,
                 gmat,
                 share_Z=False,
                 nb_init=True,
                 **kwargs):

        Layer.__init__(self, input_prop_dim=False, **kwargs)

        self.kern = kern
        self.num_nodes = num_nodes
        self.dim_per_in, self.dim_per_out = dim_per_in, dim_per_out
        self.gmat = gmat
        self.share_Z = share_Z
        self.nb_init = nb_init
        self.num_outputs = num_nodes * dim_per_out
        self.num_inducing = Z.shape[0]

        self.q_mu = Parameter(
            np.zeros((self.num_inducing, num_nodes * dim_per_out)))
        self.mean_function = ParamList([], trainable=False)
        self.q_sqrt_lst = ParamList([])
        transform = transforms.LowerTriangular(self.num_inducing,
                                               num_matrices=self.dim_per_out)

        if share_Z:
            self.feature = InducingPoints(Z)
        else:
            self.feature = ParamList([])  # InducingPoints(Z)

        for nd in range(num_nodes):
            if mean_function:
                self.mean_function.append(mean_function[nd])
            else:
                self.mean_function.append(Zero())
            if share_Z:
                pa_nd = self.pa_idx(nd)
                Ku_nd = self.kern[nd].compute_K_symm(Z)
                Lu_nd = np.linalg.cholesky(Ku_nd + np.eye(Z.shape[0]) *
                                           settings.jitter)
                q_sqrt = np.tile(Lu_nd[None, :, :], [dim_per_out, 1, 1])
                self.q_sqrt_lst.append(Parameter(q_sqrt, transform=transform))
            else:
                pa_nd = self.pa_idx(nd)
                Z_tmp = Z[:, pa_nd].copy()
                self.feature.append(InducingPoints(Z_tmp))
                Ku_nd = self.kern[nd].compute_K_symm(Z_tmp)
                Lu_nd = np.linalg.cholesky(Ku_nd + np.eye(Z_tmp.shape[0]) *
                                           settings.jitter)
                q_sqrt = np.tile(Lu_nd[None, :, :], [dim_per_out, 1, 1])
                self.q_sqrt_lst.append(Parameter(q_sqrt, transform=transform))

        self.needs_build_cholesky = True
Exemplo n.º 3
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    def _init_layers(self):
        self.layers = []

        for i in range(self.nLayers):
            self.layers.append(
                SVGP_Layer(layer_id=i,
                           Z=None,
                           U=self.U,
                           kern=self.kernels[i],
                           num_outputs=self.num_classes,
                           mean_function=Zero()))

        self.layers = ParamList(self.layers)
Exemplo n.º 4
0
    def __init__(self,
                 X,
                 Y,
                 likelihood,
                 layers,
                 minibatch_size=None,
                 num_samples=1,
                 **kwargs):
        """

        :param X: List of training inputs where each element of the list is a numpy array corresponding to the inputs of one fidelity.
        :param Y: List of training targets where each element of the list is a numpy array corresponding to the inputs of one fidelity.
        :param likelihood: gpflow likelihood object for use at the final layer
        :param layers: List of doubly_stochastic_dgp.layers.Layer objects
        :param minibatch_size: Minibatch size if using minibatch trainingz
        :param num_samples: Number of samples when propagating predictions through layers
        :param kwargs: kwarg inputs to gpflow.models.Model
        """

        Model.__init__(self, **kwargs)

        self.Y_list = Y
        self.X_list = X
        self.minibatch_size = minibatch_size

        self.num_samples = num_samples

        # This allows a training regime where the first layer is trained first by itself, then the subsequent layer
        # and so on.
        self._train_upto_fidelity = -1

        if minibatch_size:
            for i, (x, y) in enumerate(zip(X, Y)):
                setattr(self, "num_data" + str(i), x.shape[0])
                setattr(self, "X" + str(i), Minibatch(x,
                                                      minibatch_size,
                                                      seed=0))
                setattr(self, "Y" + str(i), Minibatch(y,
                                                      minibatch_size,
                                                      seed=0))
        else:
            for i, (x, y) in enumerate(zip(X, Y)):
                setattr(self, "num_data" + str(i), x.shape[0])
                setattr(self, "X" + str(i), DataHolder(x))
                setattr(self, "Y" + str(i), DataHolder(y))

        self.num_layers = len(layers)
        self.layers = ParamList(layers)

        self.likelihood = BroadcastingLikelihood(likelihood)
Exemplo n.º 5
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    def __init__(self, X, adj, layers, sample, n_samples, K,
                 neighbors=None, loss_type="link_full", label=None,
                 pos_edges=None, neg_edges=None, idx_train=None,
                 linear_layer=False, n_split=None, name="GCGP_base", **kwargs):
        """
        :param X: tensor placeholder
        :param adj: sparse tensor placeholder
        :param label:
        :param layers:
        :param sample:
        :param n_samples:
        :param K:
        :param neighbors: n-array, [n_nodes, K]
        """
        Model.__init__(self, name=name, **kwargs)

        self.X = X
        self.adj = adj
        self.loss_type = loss_type
        self.label = label
        self.pos_edges = pos_edges
        self.neg_edges = neg_edges
        self.idx_train = idx_train
        self.n_split = n_split
        self.linear_layer = linear_layer
        self.layers = ParamList(layers)

        self.sample = sample
        self.n_samples = n_samples
        self.K = K

        # indices for neighbor sampling
        self.neighbor_indices = [None] * 4

        if self.sample == "neighbor":
            assert neighbors is not None  # neighbors should not be None when sample="neighbor"
            self.update_neighbor_indices(neighbors.shape[0], neighbors)

        if self.loss_type == "classification":
            self.likelihood = gpflow.likelihoods.MultiClass(len(np.unique(self.label)))

        if self.loss_type == "regression":
            self.likelihood = gpflow.likelihoods.Gaussian(variance=0.1)

        if self.linear_layer:
            with tf.variable_scope("linear_weight"):
                self.W = tf.get_variable(name="linear_w", shape=[self.layers[-1].num_outputs, self.label.shape[1]],
                                         dtype=settings.float_type, initializer=tf.glorot_uniform_initializer())
Exemplo n.º 6
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    def __init__(self, X, Y, likelihood, layers,
                 minibatch_size=None,
                 num_samples=1):
        Model.__init__(self)
        self.num_samples = num_samples

        self.num_data = X.shape[0]
        if minibatch_size:
            self.X = Minibatch(X, minibatch_size, seed=0)
            self.Y = Minibatch(Y, minibatch_size, seed=0)
        else:
            self.X = DataHolder(X)
            self.Y = DataHolder(Y)

        self.likelihood = BroadcastingLikelihood(likelihood)

        self.layers = ParamList(layers)
Exemplo n.º 7
0
    def __init__(self,
                 X,
                 Y,
                 time_vec,
                 likelihood,
                 layers,
                 minibatch_size=100,
                 num_samples=1,
                 num_data=None,
                 wfunc='exp',
                 **kwargs):
        Model.__init__(self, **kwargs)
        self.num_samples = num_samples

        print(np.ndim(X))
        if np.ndim(X) == 2:
            self.num_data = num_data or X.shape[0]
            self.X = wMinibatch(X,
                                time_vec,
                                batch_size=minibatch_size,
                                seed=0,
                                wfunc=wfunc)
            self.Y = wMinibatch(Y,
                                time_vec,
                                batch_size=minibatch_size,
                                seed=0,
                                wfunc=wfunc)
        else:
            self.num_data = num_data or X.shape[1]
            self.X = wpMinibatch(X,
                                 time_vec,
                                 batch_size=minibatch_size,
                                 seed=0,
                                 wfunc=wfunc)
            self.Y = wpMinibatch(Y,
                                 time_vec,
                                 batch_size=minibatch_size,
                                 seed=0,
                                 wfunc=wfunc)
            self.m = 4

        self.likelihood = BroadcastingLikelihood(likelihood)

        self.layers = ParamList(layers)
Exemplo n.º 8
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    def __init__(self,
                 X,
                 Y,
                 likelihood,
                 layers,
                 minibatch_size=None,
                 num_samples=1,
                 num_data=None,
                 div_weights=None,
                 **kwargs):
        Model.__init__(self, **kwargs)
        self.num_samples = num_samples

        self.num_data = num_data or X.shape[0]
        if minibatch_size:
            self.X = Minibatch(X, minibatch_size, seed=0)
            self.Y = Minibatch(Y, minibatch_size, seed=0)
        else:
            self.X = DataHolder(X)
            self.Y = DataHolder(Y)

        self.likelihood = BroadcastingLikelihood(likelihood)

        self.layers = ParamList(layers)
        """CHANGES START"""
        """Weights for the uncertainty quantifiers (per layer)"""
        if div_weights is None:
            div_weights = [1.0] * len(
                layers)  #multiply by 1, i.e. don't change
        elif type(div_weights) == list and len(div_weights) != len(layers):
            print(
                "WARNING! You specified a list of weights for the " +
                "uncertainty quantifiers, but your DGP has more/less layers " +
                "than the number of weights you specified! " +
                "We set all weights to 1.0")
            div_weights = [1.0] * len(layers)
        elif type(div_weights) == list and len(div_weights) == len(layers):
            div_weights = div_weights
        """Distribute the weights into the layers"""
        for layer, weight in zip(layers, div_weights):
            layer.set_weight(weight)
        """CHANGES EEND"""
Exemplo n.º 9
0
class SVGPG_Layer(Layer):
    def __init__(self, kern, Z, mean_function, num_nodes, dim_per_in, dim_per_out,
                 gmat, share_Z=False, nb_init=True, **kwargs):

        Layer.__init__(self, input_prop_dim=False, **kwargs)

        self.kern = kern
        self.num_nodes = num_nodes
        self.dim_per_in, self.dim_per_out = dim_per_in, dim_per_out
        self.gmat = gmat
        self.share_Z = share_Z
        self.nb_init = nb_init
        self.num_outputs = num_nodes * dim_per_out
        self.num_inducing = Z.shape[0]

        self.q_mu = Parameter(np.zeros((self.num_inducing, num_nodes * dim_per_out)))
        self.mean_function = ParamList([], trainable=False)
        self.q_sqrt_lst = ParamList([])
        transform = transforms.LowerTriangular(self.num_inducing, num_matrices=self.dim_per_out)

        if share_Z:
            self.feature = InducingPoints(Z)
        else:
            self.feature = ParamList([])  # InducingPoints(Z)

        for nd in range(num_nodes):
            if mean_function:
                self.mean_function.append(mean_function[nd])
            else:
                self.mean_function.append(Zero())
            if share_Z:
                pa_nd = self.pa_idx(nd)
                Ku_nd = self.kern[nd].compute_K_symm(Z)
                Lu_nd = np.linalg.cholesky(Ku_nd + np.eye(Z.shape[0]) * settings.jitter)
                q_sqrt = np.tile(Lu_nd[None, :, :], [dim_per_out, 1, 1])
                self.q_sqrt_lst.append(Parameter(q_sqrt, transform=transform))
            else:
                pa_nd = self.pa_idx(nd)
                Z_tmp = Z[:, pa_nd].copy()
                self.feature.append(InducingPoints(Z_tmp))
                Ku_nd = self.kern[nd].compute_K_symm(Z_tmp)
                Lu_nd = np.linalg.cholesky(Ku_nd + np.eye(Z_tmp.shape[0]) * settings.jitter)
                q_sqrt = np.tile(Lu_nd[None, :, :], [dim_per_out, 1, 1])
                self.q_sqrt_lst.append(Parameter(q_sqrt, transform=transform))

        self.needs_build_cholesky = True

    def pa_idx(self, nd):
        res = []
        for n in range(self.num_nodes):
            w = self.gmat[nd, n]
            if w > 0:
                res = res + list(range(n * self.dim_per_in, (n + 1) * self.dim_per_in))
        res = np.asarray(res)
        return res

    @params_as_tensors
    def build_cholesky_if_needed(self):
        # make sure we only compute this once
        if self.needs_build_cholesky:
            self.Ku, self.Lu = [None] * self.num_nodes, [None] * self.num_nodes
            self.Ku_tiled_lst, self.Lu_tiled_lst = [], []
            for nd in range(self.num_nodes):
                if self.share_Z:
                    Ku_nd = self.feature.Kuu(self.kern[nd], jitter=settings.jitter)
                else:
                    Ku_nd = self.feature[nd].Kuu(self.kern[nd], jitter=settings.jitter)
                Lu_nd = tf.cholesky(Ku_nd)
                self.Ku[nd] = Ku_nd
                self.Lu[nd] = Lu_nd
                self.Ku_tiled_lst.append(tf.tile(Ku_nd[None, :, :], [self.dim_per_out, 1, 1]))
                self.Lu_tiled_lst.append(tf.tile(Lu_nd[None, :, :], [self.dim_per_out, 1, 1]))
            self.needs_build_cholesky = False

    @time_it
    def conditional_ND(self, X, full_cov=False):
        self.build_cholesky_if_needed()

        if self.share_Z:
            return self.conditional_ND_share_Z(X, full_cov=False)
        else:
            return self.conditional_ND_not_share_Z(X, full_cov=False)

    def conditional_ND_share_Z(self, X, full_cov=False):
        mean_lst, var_lst, A_tiled_lst = [], [], []
        for nd in range(self.num_nodes):
            pa_nd = self.pa_idx(nd)
            Kuf_nd = self.feature.Kuf(self.kern[nd], X)

            A_nd = tf.matrix_triangular_solve(self.Lu[nd], Kuf_nd, lower=True)
            A_nd = tf.matrix_triangular_solve(tf.transpose(self.Lu[nd]), A_nd, lower=False)
            mean_tmp = tf.matmul(A_nd, self.q_mu[:, nd * self.dim_per_out:(nd + 1) * self.dim_per_out],
                                 transpose_a=True)
            X_tmp = tf.gather(X, pa_nd, axis=1)
            if self.nb_init:
                mean_tmp += self.mean_function[nd](X_tmp)
            else:
                mean_tmp += self.mean_function[nd](X[:, nd * self.dim_per_in:(nd + 1) * self.dim_per_in])
            mean_lst.append(mean_tmp)

            A_tiled_lst.append(tf.tile(A_nd[None, :, :], [self.dim_per_out, 1, 1]))
            SK_nd = -self.Ku_tiled_lst[nd]
            q_sqrt_nd = self.q_sqrt_lst[nd]
            with params_as_tensors_for(q_sqrt_nd, convert=True):
                SK_nd += tf.matmul(q_sqrt_nd, q_sqrt_nd, transpose_b=True)

            B_nd = tf.matmul(SK_nd, A_tiled_lst[nd])
            # (num_latent, num_X)
            delta_cov_nd = tf.reduce_sum(A_tiled_lst[nd] * B_nd, 1)
            Kff_nd = self.kern[nd].Kdiag(X)

            # either (1, num_X) + (num_latent, num_X)
            var_nd = tf.expand_dims(Kff_nd, 0) + delta_cov_nd
            var_nd = tf.transpose(var_nd)

            var_lst.append(var_nd)

        mean = tf.concat(mean_lst, axis=1)
        var = tf.concat(var_lst, axis=1)
        return mean, var

    def conditional_ND_not_share_Z(self, X, full_cov=False):
        mean_lst, var_lst, A_tiled_lst = [], [], []
        for nd in range(self.num_nodes):
            pa_nd = self.pa_idx(nd)
            X_tmp = tf.gather(X, pa_nd, axis=1)
            Kuf_nd = self.feature[nd].Kuf(self.kern[nd], X_tmp)

            A_nd = tf.matrix_triangular_solve(self.Lu[nd], Kuf_nd, lower=True)
            A_nd = tf.matrix_triangular_solve(tf.transpose(self.Lu[nd]), A_nd, lower=False)

            mean_tmp = tf.matmul(A_nd, self.q_mu[:, nd * self.dim_per_out:(nd + 1) * self.dim_per_out],
                                 transpose_a=True)
            if self.nb_init:
                mean_tmp += self.mean_function[nd](X_tmp)
            else:
                mean_tmp += self.mean_function[nd](X[:, nd * self.dim_per_in:(nd + 1) * self.dim_per_in])
            mean_lst.append(mean_tmp)
            A_tiled_lst.append(tf.tile(A_nd[None, :, :], [self.dim_per_out, 1, 1]))

            SK_nd = -self.Ku_tiled_lst[nd]
            q_sqrt_nd = self.q_sqrt_lst[nd]
            with params_as_tensors_for(q_sqrt_nd, convert=True):
                SK_nd += tf.matmul(q_sqrt_nd, q_sqrt_nd, transpose_b=True)

            B_nd = tf.matmul(SK_nd, A_tiled_lst[nd])

            # (num_latent, num_X)
            delta_cov_nd = tf.reduce_sum(A_tiled_lst[nd] * B_nd, 1)
            Kff_nd = self.kern[nd].Kdiag(X_tmp)

            # (1, num_X) + (num_latent, num_X)
            var_nd = tf.expand_dims(Kff_nd, 0) + delta_cov_nd
            var_nd = tf.transpose(var_nd)

            var_lst.append(var_nd)

        mean = tf.concat(mean_lst, axis=1)
        var = tf.concat(var_lst, axis=1)
        return mean, var

    @time_it
    def KL(self):
        """
        The KL divergence from the variational distribution to the prior

        :return: KL divergence from N(q_mu, q_sqrt) to N(0, I), independently for each GP
        """

        self.build_cholesky_if_needed()

        KL = -0.5 * self.num_inducing * self.num_nodes * self.dim_per_out

        for nd in range(self.num_nodes):
            q_sqrt_nd = self.q_sqrt_lst[nd]
            with params_as_tensors_for(q_sqrt_nd, convert=True):
                KL -= 0.5 * tf.reduce_sum(tf.log(tf.matrix_diag_part(q_sqrt_nd) ** 2))

                KL += tf.reduce_sum(tf.log(tf.matrix_diag_part(self.Lu[nd]))) * self.dim_per_out
                KL += 0.5 * tf.reduce_sum(
                    tf.square(tf.matrix_triangular_solve(self.Lu_tiled_lst[nd], q_sqrt_nd, lower=True)))
                q_mu_nd = self.q_mu[:, nd * self.dim_per_out:(nd + 1) * self.dim_per_out]
                Kinv_m_nd = tf.cholesky_solve(self.Lu[nd], q_mu_nd)
                KL += 0.5 * tf.reduce_sum(q_mu_nd * Kinv_m_nd)

        return KL
Exemplo n.º 10
0
def init_layers_graph(X, Y, Z, kernels, gmat,
                      num_layers=2,
                      num_nodes=None,
                      dim_per_node=5,
                      dim_per_X=5, dim_per_Y=5,
                      share_Z=False,
                      nb_init=True):
    layers = []

    def pa_idx(nd, dim_per_in):
        res = []
        for n in range(num_nodes):
            w = gmat[nd, n]
            if w > 0:
                # print(res, range(n*self.dim_per_in, (n+1)*self.dim_per_in))
                res = res + list(range(n * dim_per_in, (n + 1) * dim_per_in))
        res = np.asarray(res)
        return res

    X_running, Z_running = X.copy(), Z.copy()
    for l in range(num_layers - 1):
        if l == 0:
            dim_in = dim_per_X
            dim_out = dim_per_node
        else:
            dim_in = dim_per_node
            dim_out = dim_per_node
        # print(dim_in, dim_out)
        X_running_tmp = np.zeros((X.shape[0], dim_out * num_nodes))
        Z_running_tmp = np.zeros((Z.shape[0], dim_out * num_nodes))
        mf_lst = ParamList([], trainable=False)
        for nd in range(num_nodes):
            if nb_init:
                pa = pa_idx(nd, dim_in)
            else:
                pa = np.asarray(range(nd * dim_in, (nd + 1) * dim_in))
            agg_dim_in = len(pa)

            if agg_dim_in == dim_out:
                mf = Identity()

            else:
                if agg_dim_in > dim_out:  # stepping down, use the pca projection
                    # _, _, V = np.linalg.svd(X_running[:, nd*dim_in : (nd+1)*dim_in], full_matrices=False)
                    _, _, V = np.linalg.svd(X_running[:, pa], full_matrices=False)
                    W = V[:dim_out, :].T

                else:  # stepping up, use identity + padding
                    W = np.concatenate([np.eye(agg_dim_in), np.zeros((agg_dim_in, dim_out - agg_dim_in))], 1)

                mf = Linear(W)
                mf.set_trainable(False)
            mf_lst.append(mf)
            if agg_dim_in != dim_out:
                # print(Z_running_tmp[:, nd*dim_out:(nd+1)*dim_out].shape, Z_running[:, nd*dim_in:(nd+1)*dim_in].shape,
                #       W.shape, Z_running[:, nd*dim_in:(nd+1)*dim_in].dot(W).shape)
                Z_running_tmp[:, nd * dim_out:(nd + 1) * dim_out] = Z_running[:, pa].dot(W)
                X_running_tmp[:, nd * dim_out:(nd + 1) * dim_out] = X_running[:, pa].dot(W)
            else:
                Z_running_tmp[:, nd * dim_out:(nd + 1) * dim_out] = Z_running[:, pa]
                X_running_tmp[:, nd * dim_out:(nd + 1) * dim_out] = X_running[:, pa]

        layers.append(
            SVGPG_Layer(kernels[l], Z_running, mf_lst, num_nodes, dim_in, dim_out, gmat, share_Z=share_Z, nb_init=nb_init))
        Z_running = Z_running_tmp
        X_running = X_running_tmp

    # final layer
    if num_layers == 1:
        fin_dim_in = dim_per_X
    else:
        fin_dim_in = dim_per_node
    layers.append(
        SVGPG_Layer(kernels[-1], Z_running, None, num_nodes, fin_dim_in, dim_per_Y, gmat, share_Z=share_Z, nb_init=nb_init))
    return layers
Exemplo n.º 11
0
    def __init__(self,
                 datasets=[],
                 inducing_locations=[],
                 kernels=[],
                 noise_sigmas=[],
                 minibatch_sizes=[],
                 mixing_weight=None,
                 parent_mixtures=None,
                 masks=None,
                 num_samples=1,
                 **kwargs):
        """
            datasets: an array of arrays [X_a, Y_a] ordered by 'trust', ie datasets[0] is the most reliable 
            inducing_points_locations: an array of inducing locations for each of the datasets  
            kernels: an array of kernels for each of the datasets  
            noise_sigmas: an array of noise_sigmas for each of the datasets  
            mixing_weight (MR_Mixing_Weight): an object that will combine the predictions from each of the local experts
            parent_mixtures: an array of parent mixture models
        """
        Model.__init__(self, **kwargs)

        self.dataset_sizes = []
        for d in datasets:
            self.dataset_sizes.append(d[0].shape[0])

        self.num_datasets = len(datasets)
        self.X = []
        self.Y = []
        self.Z = inducing_locations
        self.masks = masks
        self.MASKS = []
        self.kernels = kernels
        self.noise_sigmas = noise_sigmas
        self.num_samples = num_samples

        #gpflow models are Parameterized objects
        print(parent_mixtures)
        self.parent_mixtures = ParamList(
            parent_mixtures) if parent_mixtures is not None else None

        self.mixing_weight = mixing_weight

        minibatch = False
        for i, d in enumerate(datasets):
            #TODO: can we just wrap with a ParamList?
            if minibatch:
                _x = Minibatch(d[0], batch_size=minibatch_sizes[i], seed=0)
                _y = Minibatch(d[1], batch_size=minibatch_sizes[i], seed=0)
            else:
                _x = DataHolder(d[0])
                _y = DataHolder(d[1])

            #Check we have some masks
            if self.masks:
                #Check if we have a mask for this dataset
                _mask = None
                if self.masks[i] is not None:
                    if minibatch:
                        _mask = Minibatch(self.masks[i],
                                          batch_size=minibatch_sizes[0],
                                          seed=0)
                    else:
                        _mask = DataHolder(self.masks[i])

            #make it so GPFlow can find _x, _y
            setattr(self, 'x_{i}'.format(i=i), _x)
            setattr(self, 'y_{i}'.format(i=i), _y)
            if self.masks:
                setattr(self, 'mask_{i}'.format(i=i), _mask)

            #save references
            self.X.append(self.__dict__['x_{i}'.format(i=i)])
            self.Y.append(self.__dict__['y_{i}'.format(i=i)])
            if self.masks:
                self.MASKS.append(self.__dict__['mask_{i}'.format(i=i)])

        self.setup()
Exemplo n.º 12
0
    def __init__(self,
                 latent_dim,
                 Y,
                 inputs=None,
                 emissions=None,
                 px1_mu=None,
                 px1_cov=None,
                 kern=None,
                 Z=None,
                 n_ind_pts=100,
                 mean_fn=None,
                 Q_diag=None,
                 Umu=None,
                 Ucov_chol=None,
                 qx1_mu=None,
                 qx1_cov=None,
                 As=None,
                 bs=None,
                 Ss=None,
                 n_samples=100,
                 batch_size=None,
                 chunking=False,
                 seed=None,
                 parallel_iterations=10,
                 jitter=gp.settings.numerics.jitter_level,
                 name=None):

        super().__init__(latent_dim,
                         Y[0],
                         inputs=None if inputs is None else inputs[0],
                         emissions=emissions,
                         px1_mu=px1_mu,
                         px1_cov=None,
                         kern=kern,
                         Z=Z,
                         n_ind_pts=n_ind_pts,
                         mean_fn=mean_fn,
                         Q_diag=Q_diag,
                         Umu=Umu,
                         Ucov_chol=Ucov_chol,
                         qx1_mu=qx1_mu,
                         qx1_cov=None,
                         As=None,
                         bs=None,
                         Ss=False if Ss is False else None,
                         n_samples=n_samples,
                         seed=seed,
                         parallel_iterations=parallel_iterations,
                         jitter=jitter,
                         name=name)

        self.T = [Y_s.shape[0] for Y_s in Y]
        self.T_tf = tf.constant(self.T, dtype=gp.settings.int_type)
        self.max_T = max(self.T)
        self.sum_T = float(sum(self.T))
        self.n_seq = len(self.T)
        self.batch_size = batch_size
        self.chunking = chunking

        if self.batch_size is None:
            self.Y = ParamList(Y, trainable=False)
        else:
            _Y = np.stack([
                np.concatenate(
                    [Ys, np.zeros((self.max_T - len(Ys), self.obs_dim))])
                for Ys in Y
            ])
            self.Y = Param(_Y, trainable=False)

        if inputs is not None:
            if self.batch_size is None:
                self.inputs = ParamList(inputs, trainable=False)
            else:
                desired_length = self.max_T if self.chunking else self.max_T - 1
                _inputs = [
                    np.concatenate([
                        inputs[s],
                        np.zeros(
                            (desired_length - len(inputs[s]), self.input_dim))
                    ]) for s in range(self.n_seq)
                ]  # pad the inputs
                self.inputs = Param(_inputs, trainable=False)

        if qx1_mu is None:
            self.qx1_mu = Param(np.zeros((self.n_seq, self.latent_dim)))

        self.qx1_cov_chol = Param(
            np.tile(np.eye(self.latent_dim)[None, ...], [self.n_seq, 1, 1])
            if qx1_cov is None else np.linalg.cholesky(qx1_cov),
            transform=gtf.LowerTriangular(self.latent_dim,
                                          num_matrices=self.n_seq))

        _As = [np.ones((T_s - 1, self.latent_dim))
               for T_s in self.T] if As is None else As
        _bs = [np.zeros((T_s - 1, self.latent_dim))
               for T_s in self.T] if bs is None else bs
        if Ss is not False:
            _S_chols = [np.tile(self.Q_sqrt.value.copy()[None, ...], [T_s - 1, 1]) for T_s in self.T] if Ss is None \
                else [np.sqrt(S) if S.ndim == 2 else np.linalg.cholesky(S) for S in Ss]

        if self.batch_size is None:
            self.As = ParamList(_As)
            self.bs = ParamList(_bs)
            if Ss is not False:
                self.S_chols = ParamList([
                    Param(Sc,
                          transform=gtf.positive if Sc.ndim == 2 else
                          gtf.LowerTriangular(self.latent_dim,
                                              num_matrices=Sc.shape[0]))
                    for Sc in _S_chols
                ])
        else:
            _As = np.stack([
                np.concatenate(
                    [_A,
                     np.zeros((self.max_T - len(_A) - 1, *_A.shape[1:]))])
                for _A in _As
            ])
            _bs = np.stack([
                np.concatenate([
                    _b,
                    np.zeros((self.max_T - len(_b) - 1, self.latent_dim))
                ]) for _b in _bs
            ])
            self.As = Param(_As)
            self.bs = Param(_bs)
            if Ss is not False:
                _S_chols = [
                    np.concatenate([
                        _S,
                        np.zeros((self.max_T - len(_S) - 1, *_S.shape[1:]))
                    ]) for _S in _S_chols
                ]
                _S_chols = np.stack(_S_chols)
                self.S_chols = Param(_S_chols, transform=gtf.positive if _S_chols.ndim == 3 else \
                    gtf.LowerTriangular(self.latent_dim, num_matrices=(self.n_seq, self.max_T - 1)))

        self.multi_diag_px1_cov = False
        if isinstance(px1_cov, list):  # different prior for each sequence
            _x1_cov = np.stack(px1_cov)
            _x1_cov = np.sqrt(
                _x1_cov) if _x1_cov.ndim == 2 else np.linalg.cholesky(_x1_cov)
            _transform = None if _x1_cov.ndim == 2 else gtf.LowerTriangular(
                self.latent_dim, num_matrices=self.n_seq)
            self.multi_diag_px1_cov = _x1_cov.ndim == 2
        elif isinstance(px1_cov, np.ndarray):  # same prior for each sequence
            assert px1_cov.ndim < 3
            _x1_cov = np.sqrt(
                px1_cov) if px1_cov.ndim == 1 else np.linalg.cholesky(px1_cov)
            _transform = None if px1_cov.ndim == 1 else gtf.LowerTriangular(
                self.latent_dim, squeeze=True)

        self.px1_cov_chol = None if px1_cov is None else Param(
            _x1_cov, trainable=False, transform=_transform)

        if self.chunking:
            px1_mu_check = len(self.px1_mu.shape) == 1
            px1_cov_check_1 = not self.multi_diag_px1_cov
            px1_cov_check_2 = self.px1_cov_chol is None or len(
                self.px1_cov_chol.shape) < 3
            assert px1_mu_check and px1_cov_check_1 and px1_cov_check_2, \
                'Only one prior over x1 allowed for chunking'
Exemplo n.º 13
0
 def to_param_list(var_list, name):
     param_list = []
     for idx, var in enumerate(var_list):
         name_idx = '{name}_{idx}'.format(name=name, idx=idx)
         param_list.append(Param(var, dtype=float_type, name=name_idx))
     return ParamList(param_list)