示例#1
0
class HetmogpWrapeper(BaseEstimator):
    def __init__(self, M=20, vem_iters=3):
        self.likelihoods_list = [Bernoulli(), Bernoulli()]  # Real + Binary
        self.likelihood = HetLikelihood(self.likelihoods_list)
        self.Y_metadata = self.likelihood.generate_metadata()
        self.D = self.likelihood.num_output_functions(self.Y_metadata)
        self.M = M
        self.vem_iters = vem_iters
        pass

    def fit(self, X_l, y_l, X_h, y_h):
        input_dim = X_h.shape[1]
        X = [X_l, X_h]
        Y = [y_l.reshape(-1, 1), y_h.reshape(-1, 1)]
        Q = 2  # number of latent functions
        ls_q = np.array(([.05] * Q))
        var_q = np.array(([.5] * Q))
        kern_list = util.latent_functions_prior(Q,
                                                lenghtscale=ls_q,
                                                variance=var_q,
                                                input_dim=input_dim)
        #Z = np.linspace(0, 1, self.M)
        #Z = Z[:, np.newaxis]
        Z = np.random.randn(self.M, input_dim)
        self.model = SVMOGP(X=X,
                            Y=Y,
                            Z=Z,
                            kern_list=kern_list,
                            likelihood=self.likelihood,
                            Y_metadata=self.Y_metadata)
        self.model = VEM(self.model,
                         stochastic=False,
                         vem_iters=self.vem_iters,
                         optZ=True,
                         verbose=False,
                         verbose_plot=False,
                         non_chained=False)

    def predict_proba(self, X):
        htmogp_1_m, htmogp_1_v = self.model._raw_predict_f(
            X, output_function_ind=1)
        pos_preds = expit(htmogp_1_m)
        return np.hstack((1 - pos_preds, pos_preds))

    def predict(self, X):
        proba = self.predict_proba(X)[:, 1]
        return (proba > 0.5).astype(int)
示例#2
0
        n_iter = int(config.N_iter)
        all_NLPD = []
        Times_all = []
        ELBO_all = []

        random.seed(101)
        np.random.seed(101)
        ELBO = []
        NLPD = []
        myTimes = []

        Y = Ytrain.copy()
        X = Xtrain.copy()

        J = likelihood.num_output_functions(Y_metadata)  # This function indicates how many J latent functions we need
        print('J is:',J)
        np.random.seed(myseed)
        if not convolved:
            if ('toy' in dataset):
                ls_q = 1 * np.sqrt(Dim) * (np.random.rand(Q) + 0.001)  # 10 * np.ones(Q)   era 0.01
            elif ('zip_conv' in dataset):
                ls_q = 0.1 * np.sqrt(Dim) * (np.random.rand(Q) + 0.001)
            else:
                ls_q = 0.1 * np.sqrt(Dim) * (np.random.rand(Q) + 0.001)  # 10 * np.ones(Q)   era 0.01
            print("Initial lengthscales uq:", ls_q)
        else:
            if ('toy1c' in dataset):
                ls_q = 0.0001 * np.sqrt(Dim) * (np.random.rand(Q) + 0.001)  # 10 * np.ones(Q)   era 0.01
                lenghtscale = 0.1 * np.sqrt(Dim) * (np.random.rand(J) * np.random.rand(J))
                length_Tq = 0.1 * np.sqrt(Dim) * (np.random.rand(Q) * np.random.rand(Q))
示例#3
0
def load_toy1_conv(N=1000, input_dim=1):
    if input_dim == 2:
        Nsqrt = int(N**(1.0 / input_dim))
    print('input_dim:', input_dim)
    # Q = 5  # number of latent functions

    # Heterogeneous Likelihood Definition
    # likelihoods_list = [Gaussian(sigma=1.0), Bernoulli()] # Real + Binary
    likelihoods_list = [Gaussian(sigma=0.1),
                        Gaussian(sigma=0.1)]  # Real + Binary
    # likelihoods_list = [Gaussian(sigma=1.0)]
    likelihood = HetLikelihood(likelihoods_list)
    Y_metadata = likelihood.generate_metadata()
    D = likelihoods_list.__len__()
    J = likelihood.num_output_functions(Y_metadata)
    Q = 1
    """""" """""" """""" """""" """"""
    rescale = 10
    Dim = input_dim
    if input_dim == 2:
        xy = rescale * np.linspace(-1.0, 1.0, Nsqrt)
        xx = rescale * np.linspace(-1.0, 1.0, Nsqrt)
        XX, XY = np.meshgrid(xx, xy)
        XX = XX.reshape(Nsqrt**2, 1)
        XY = XY.reshape(Nsqrt**2, 1)
        Xtoy = np.hstack((XX, XY))
    else:
        minis = -rescale * np.ones(Dim)
        maxis = rescale * np.ones(Dim)
        Xtoy = np.linspace(minis[0], maxis[0], N).reshape(1, -1)
        for i in range(Dim - 1):
            Xaux = np.linspace(minis[i + 1], maxis[i + 1], N)
            Xtoy = np.concatenate(
                (Xtoy, Xaux[np.random.permutation(N)].reshape(1, -1)), axis=0)
            # Z = np.concatenate((Z, Zaux.reshape(1, -1)), axis=0)
        Xtoy = 1.0 * Xtoy.T

    def latent_functions_prior(Q,
                               lengthscale=None,
                               input_dim=None,
                               name='kern_q'):
        #lenghtscale = rescale * np.array([0.5])  # This is the one used for previous experiments
        #lenghtscale = rescale * lengthscale
        lenghtscale = lengthscale
        variance = 1 * np.ones(Q)
        kern_list = []
        for q in range(Q):
            # print("length:",lenghtscale[q])
            # print("var:", variance[q])
            kern_q = GPy.kern.RBF(input_dim=input_dim,
                                  lengthscale=lenghtscale[q],
                                  variance=variance[q],
                                  name='rbf')
            kern_q.name = name + str(q)
            kern_list.append(kern_q)
        return kern_list

    kern_list_uq = latent_functions_prior(Q,
                                          lengthscale=np.array([0.1]),
                                          input_dim=Dim,
                                          name='kern_q')
    kern_list_Gdj = latent_functions_prior(J,
                                           lengthscale=np.array([0.3, 0.7]),
                                           input_dim=Dim,
                                           name='kern_G')
    kern_aux = GPy.kern.RBF(input_dim=Dim,
                            lengthscale=1.0,
                            variance=1.0,
                            name='rbf_aux',
                            ARD=False) + GPy.kern.White(input_dim=Dim)
    kern_aux.white.variance = 1e-6

    # True U and F functions
    def experiment_true_u_functions(kern_list, kern_list_Gdj, X):
        Q = kern_list.__len__()
        # for d,X in enumerate(X_list):
        u_latent = np.zeros((X.shape[0], Q))
        np.random.seed(104)
        for q in range(Q):
            u_latent[:, q] = np.random.multivariate_normal(
                np.zeros(X.shape[0]), kern_list[q].K(X))

        return u_latent

    def experiment_true_f_functions(kern_u, kern_G, kern_aux, X, Q, J):

        W = W_lincombination(Q, J)
        # print(W)
        # for j in range(J):
        f_j = np.zeros((X.shape[0], J))
        for j in range(J):
            for q in range(Q):
                util.update_conv_Kff(kern_u[q], kern_G[j], kern_aux)
                #f_j += (W[q] * true_u[:, q]).T
                f_j[:, j] += W[q][j] * np.random.multivariate_normal(
                    np.zeros(X.shape[0]), kern_aux.K(X))
        # true_f.append(f_d)

        return f_j

    # True Combinations
    def W_lincombination(Q, J):
        W_list = []
        # q=1
        for q in range(Q):
            # W_list.append(np.array(([[-0.5], [0.1]])))
            if q == 0:
                # W_list.append(0.3*np.random.randn(J, 1))
                W_list.append(np.array([-0.5, 2.1])[:, None])
            elif q == 1:
                # W_list.append(2.0 * np.random.randn(J, 1))
                W_list.append(np.array([
                    1.4,
                    0.3,
                ])[:, None])
            else:
                # W_list.append(10.0 * np.random.randn(J, 1)+0.1)
                W_list.append(np.array([
                    0.1,
                    -0.8,
                ])[:, None])

        return W_list

    """""" """""" """""" """""" """""" ""

    # True functions values for inputs X
    f_index = Y_metadata['function_index'].flatten()
    J = f_index.__len__()
    trueF = experiment_true_f_functions(kern_list_uq, kern_list_Gdj, kern_aux,
                                        Xtoy, Q, J)
    # if input_dim==2:
    #     #from mpl_toolkits.mplot3d import Axes3D  # noqa: F401 unused import
    #
    #     from matplotlib import cm
    #     from matplotlib.ticker import LinearLocator, FormatStrFormatter
    #     fig = plt.figure()
    #     ax = fig.gca(projection='3d')
    #
    #     # Make data.
    #     # X = np.arange(-5, 5, 0.25)
    #     # Y = np.arange(-5, 5, 0.25)
    #     # X, Y = np.meshgrid(X, Y)
    #     # R = np.sqrt(X ** 2 + Y ** 2)
    #     # Z = np.sin(R)
    #
    #     # Plot the surface.
    #     surf = ax.plot_surface(Xtoy[:,0].reshape(Nsqrt,Nsqrt), Xtoy[:,1].reshape(Nsqrt,Nsqrt), trueF[:,2].reshape(Nsqrt,Nsqrt), cmap=cm.coolwarm,linewidth=0, antialiased=False)
    #
    #     # Customize the z axis.
    #     #ax.set_zlim(-1.01, 1.01)
    #     ax.zaxis.set_major_locator(LinearLocator(10))
    #     ax.zaxis.set_major_formatter(FormatStrFormatter('%.02f'))
    #
    #     # Add a color bar which maps values to colors.
    #     fig.colorbar(surf, shrink=0.5, aspect=5)
    #
    #     plt.show()
    #
    # else:
    #     plt.figure(15)
    #     plt.plot(trueF[:,1])
    #     plt.figure(16)
    #     plt.plot(trueU)

    d_index = Y_metadata['d_index'].flatten()
    F_true = []
    # for i,f_latent in enumerate(trueF):
    #    if

    for t in range(D):
        _, num_f_task, _ = likelihoods_list[t].get_metadata()
        f = np.empty((Xtoy.shape[0], num_f_task))
        for j in range(J):
            if f_index[j] == t:
                f[:, d_index[j], None] = trueF[:, j][:, None]

        F_true.append(f)

    # Generating training data Y (sampling from heterogeneous likelihood)
    Ytrain = likelihood.samples(F=F_true, Y_metadata=Y_metadata)

    #Yreg0 = (Ytrain[0] - Ytrain[0].mean(0)) / (Ytrain[0].std(0))
    #Yreg1 = (Ytrain[1] - Ytrain[1].mean(0)) / (Ytrain[1].std(0))
    #Ytrain = [Yreg0, Yreg1]
    Xtrain = []
    for d in range(likelihoods_list.__len__()):
        Xtrain.append(Xtoy)

    return Xtrain, Ytrain