def check_lower_bound(shape_mu, shape_alpha, plates_mu=(), **kwargs):
     M = GaussianARD(np.ones(plates_mu + shape_mu),
                     np.ones(plates_mu + shape_mu),
                     shape=shape_mu,
                     plates=plates_mu)
     if not ('ndim' in kwargs or 'shape' in kwargs):
         kwargs['ndim'] = len(shape_mu)
     X = GaussianARD(M,
                     2*np.ones(shape_alpha),
                     **kwargs)
     Y = GaussianARD(X,
                     3*np.ones(X.get_shape(0)),
                     **kwargs)
     Y.observe(4*np.ones(Y.get_shape(0)))
     X.update()
     Cov = 1/(2+3)
     mu = Cov * (2*1 + 3*4)
     x2 = mu**2 + Cov
     logH_X = (+ 0.5*(1+np.log(2*np.pi)) 
               + 0.5*np.log(Cov))
     logp_X = (- 0.5*np.log(2*np.pi) 
               + 0.5*np.log(2) 
               - 0.5*2*(x2 - 2*mu*1 + 1**2+1))
     r = np.prod(X.get_shape(0))
     self.assertAllClose(r * (logp_X + logH_X),
                         X.lower_bound_contribution())
示例#2
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def run():
    k = 2
    c = 5
    s = 2
    x = np.arange(10)
    y = k * x + c + s * np.random.randn(10)

    X=np.vstack([x,np.ones(len(x))]).T
    B = GaussianARD(0, 1e-6, shape=(2,))
    F = SumMultiply('i,i', B, X)
    tau = Gamma(1e-3, 1e-3)

    Y = GaussianARD(F, tau)

    Y.observe(y)
    from bayespy.inference import VB
    Q = VB(Y, B, tau)
    Q.update(repeat=1000)
    xh = np.linspace(-5, 15, 100)
    Xh = np.vstack([xh, np.ones(len(xh))]).T
    Fh = SumMultiply('i,i', B, Xh)


    bpplt.pyplot.figure()
    bpplt.plot(Fh, x=xh, scale=2)
    bpplt.plot(y, x=x, color='r', marker='x', linestyle='None')
    bpplt.plot(k*xh+c, x=xh, color='r');
    bpplt.pyplot.show()
示例#3
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def _setup_linear_regression():
    """
    Setup code for the pdf and contour tests.

    This code is from http://www.bayespy.org/examples/regression.html
    """
    np.random.seed(1)
    k = 2  # slope
    c = 5  # bias
    s = 2  # noise standard deviation

    x = np.arange(10)
    y = k * x + c + s * np.random.randn(10)
    X = np.vstack([x, np.ones(len(x))]).T

    B = GaussianARD(0, 1e-6, shape=(2, ))

    F = SumMultiply('i,i', B, X)

    tau = Gamma(1e-3, 1e-3)
    Y = GaussianARD(F, tau)
    Y.observe(y)

    Q = VB(Y, B, tau)
    Q.update(repeat=1000)
    xh = np.linspace(-5, 15, 100)
    Xh = np.vstack([xh, np.ones(len(xh))]).T
    Fh = SumMultiply('i,i', B, Xh)

    return locals()
示例#4
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def _setup_linear_regression():
    """
    Setup code for the pdf and contour tests.

    This code is from http://www.bayespy.org/examples/regression.html
    """
    np.random.seed(1)
    k = 2 # slope
    c = 5 # bias
    s = 2 # noise standard deviation

    x = np.arange(10)
    y = k*x + c + s*np.random.randn(10)
    X = np.vstack([x, np.ones(len(x))]).T

    B = GaussianARD(0, 1e-6, shape=(2,))

    F = SumMultiply('i,i', B, X)

    tau = Gamma(1e-3, 1e-3)
    Y = GaussianARD(F, tau)
    Y.observe(y)

    Q = VB(Y, B, tau)
    Q.update(repeat=1000)
    xh = np.linspace(-5, 15, 100)
    Xh = np.vstack([xh, np.ones(len(xh))]).T
    Fh = SumMultiply('i,i', B, Xh)

    return locals()
示例#5
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    def test_mask_to_parent(self):
        """
        Test the mask handling in Mixture node
        """

        K = 3
        Z = Categorical(np.ones(K)/K,
                        plates=(4,5,1))
        Mu = GaussianARD(0, 1,
                         shape=(2,),
                         plates=(4,K,5))
        Alpha = Gamma(1, 1,
                      plates=(4,K,5,2))
        X = Mixture(Z, GaussianARD, Mu, Alpha, cluster_plate=-3)
        Y = GaussianARD(X, 1, ndim=1)
        mask = np.reshape((np.mod(np.arange(4*5), 2) == 0),
                          (4,5))
        Y.observe(np.ones((4,5,2)),
                  mask=mask)
        self.assertArrayEqual(Z.mask,
                              mask[:,:,None])
        self.assertArrayEqual(Mu.mask,
                              mask[:,None,:])
        self.assertArrayEqual(Alpha.mask,
                              mask[:,None,:,None])

        pass
示例#6
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    def test_mask_to_parent(self):
        """
        Test the mask handling in Mixture node
        """

        K = 3
        Z = Categorical(np.ones(K)/K,
                        plates=(4,5))
        Mu = GaussianARD(0, 1,
                         shape=(2,),
                         plates=(4,K,5))
        Alpha = Gamma(1, 1,
                      plates=(4,K,5,2))
        X = Mixture(Z, GaussianARD, Mu, Alpha, cluster_plate=-2)
        Y = GaussianARD(X, 1)
        mask = np.reshape((np.mod(np.arange(4*5), 2) == 0),
                          (4,5))
        Y.observe(np.ones((4,5,2)), 
                  mask=mask)
        self.assertArrayEqual(Z.mask,
                              mask)
        self.assertArrayEqual(Mu.mask,
                              mask[:,None,:])
        self.assertArrayEqual(Alpha.mask,
                              mask[:,None,:,None])
                         
        pass
示例#7
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    def fit(self, X, y):
        self.weights = GaussianARD(0, 1e-6, shape=(X.shape[-1], ))
        y_mean = SumMultiply('i,i', self.weights, X)
        precision = Gamma(1, .1)
        y_obs = GaussianARD(y_mean, precision)
        y_obs.observe(y)

        Q = VB(y_obs, self.weights, precision)
        Q.update(repeat=self.n_iter, tol=self.tolerance, verbose=False)
示例#8
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    def test_riemannian_gradient(self):
        """Test Riemannian gradient of a Gamma node."""

        #
        # Without observations
        #

        # Construct model
        a = np.random.rand()
        b = np.random.rand()
        tau = Gamma(a, b)
        # Random initialization
        tau.initialize_from_parameters(np.random.rand(),
                                       np.random.rand())
        # Initial parameters
        phi0 = tau.phi
        # Gradient
        g = tau.get_riemannian_gradient()
        # Parameters after VB-EM update
        tau.update()
        phi1 = tau.phi
        # Check
        self.assertAllClose(g[0],
                            phi1[0] - phi0[0])
        self.assertAllClose(g[1],
                            phi1[1] - phi0[1])

        #
        # With observations
        #

        # Construct model
        a = np.random.rand()
        b = np.random.rand()
        tau = Gamma(a, b)
        mu = np.random.randn()
        Y = GaussianARD(mu, tau)
        Y.observe(np.random.randn())
        # Random initialization
        tau.initialize_from_parameters(np.random.rand(),
                                       np.random.rand())
        # Initial parameters
        phi0 = tau.phi
        # Gradient
        g = tau.get_riemannian_gradient()
        # Parameters after VB-EM update
        tau.update()
        phi1 = tau.phi
        # Check
        self.assertAllClose(g[0],
                            phi1[0] - phi0[0])
        self.assertAllClose(g[1],
                            phi1[1] - phi0[1])

        pass
示例#9
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    def test_lower_bound_contribution(self):

        a = 15
        b = 21
        y = 4
        x = Gamma(a, b)
        x.observe(y)
        testing.assert_allclose(
            x.lower_bound_contribution(),
            (
                a * np.log(b) +
                (a - 1) * np.log(y) -
                b * y -
                special.gammaln(a)
            )
        )

        # Just one latent node so we'll get exact marginal likelihood
        #
        # p(Y) = p(Y,X)/p(X|Y) = p(Y|X) * p(X) / p(X|Y)
        a = 2.3
        b = 4.1
        x = 1.9
        y = 4.8
        tau = Gamma(a, b)
        Y = GaussianARD(x, tau)
        Y.observe(y)
        mu = x
        nu = 2 * a
        s2 = b / a
        a_post = a + 0.5
        b_post = b + 0.5*(y - x)**2
        tau.update()
        testing.assert_allclose(
            [-b_post, a_post],
            tau.phi
        )
        testing.assert_allclose(
            Y.lower_bound_contribution() + tau.lower_bound_contribution(), # + tau.g,
            (
                special.gammaln((nu+1)/2)
                - special.gammaln(nu/2)
                - 0.5 * np.log(nu)
                - 0.5 * np.log(np.pi)
                - 0.5 * np.log(s2)
                - 0.5 * (nu + 1) * np.log(
                    1 + (y - mu)**2 / (nu * s2)
                )
            )
        )

        return
示例#10
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    def test_message_to_parents(self):
        """ Check gradient passed to inputs parent node """
        D = 3

        X = Gaussian(np.random.randn(D), random.covariance(D))
        a = Gamma(np.random.rand(D), np.random.rand(D))

        Y = GaussianARD(X, a)
        Y.observe(np.random.randn(D))

        self.assert_message_to_parent(Y, X)
        self.assert_message_to_parent(Y, a)

        pass
示例#11
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    def fit(self, X, y):
        self._init_weights()
        # self.cost,
        # self.myopic_voc(action, state),
        # self.vpi_action(action, state),
        # self.vpi(state),
        # self.expected_term_reward(state)

        self.tau = Gamma(self.prior_a, self.prior_b)
        F = SumMultiply('i,i', self.weights, X)
        y_obs = GaussianARD(F, self.tau)
        y_obs.observe(y)

        Q = VB(y_obs, self.weights)
        Q.update(repeat=10, tol=1e-4, verbose=False)
示例#12
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def pca():

    np.random.seed(41)

    M = 10
    N = 3000
    D = 5

    # Construct the PCA model
    alpha = Gamma(1e-3, 1e-3, plates=(D, ), name='alpha')
    W = GaussianARD(0, alpha, plates=(M, 1), shape=(D, ), name='W')
    X = GaussianARD(0, 1, plates=(1, N), shape=(D, ), name='X')
    tau = Gamma(1e-3, 1e-3, name='tau')
    W.initialize_from_random()
    F = SumMultiply('d,d->', W, X)
    Y = GaussianARD(F, tau, name='Y')

    # Observe data
    data = np.sum(np.random.randn(M, 1, D - 1) * np.random.randn(1, N, D - 1),
                  axis=-1) + 1e-1 * np.random.randn(M, N)
    Y.observe(data)

    # Initialize VB engine
    Q = VB(Y, X, W, alpha, tau)

    # Take one update step (so phi is ok)
    Q.update(repeat=1)
    Q.save()

    # Run VB-EM
    Q.update(repeat=200)
    bpplt.pyplot.plot(np.cumsum(Q.cputime), Q.L, 'k-')

    # Restore the state
    Q.load()

    # Run Riemannian conjugate gradient
    #Q.optimize(X, alpha, maxiter=100, collapsed=[W, tau])
    Q.optimize(W, tau, maxiter=100, collapsed=[X, alpha])
    bpplt.pyplot.plot(np.cumsum(Q.cputime), Q.L, 'r:')

    bpplt.pyplot.show()
示例#13
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def pca():

    np.random.seed(41)

    M = 10
    N = 3000
    D = 5

    # Construct the PCA model
    alpha = Gamma(1e-3, 1e-3, plates=(D,), name='alpha')
    W = GaussianARD(0, alpha, plates=(M,1), shape=(D,), name='W')
    X = GaussianARD(0, 1, plates=(1,N), shape=(D,), name='X')
    tau = Gamma(1e-3, 1e-3, name='tau')
    W.initialize_from_random()
    F = SumMultiply('d,d->', W, X)
    Y = GaussianARD(F, tau, name='Y')

    # Observe data
    data = np.sum(np.random.randn(M,1,D-1) * np.random.randn(1,N,D-1), axis=-1) + 1e-1 * np.random.randn(M,N)
    Y.observe(data)

    # Initialize VB engine
    Q = VB(Y, X, W, alpha, tau)

    # Take one update step (so phi is ok)
    Q.update(repeat=1)
    Q.save()

    # Run VB-EM
    Q.update(repeat=200)
    bpplt.pyplot.plot(np.cumsum(Q.cputime), Q.L, 'k-')

    # Restore the state
    Q.load()

    # Run Riemannian conjugate gradient
    #Q.optimize(X, alpha, maxiter=100, collapsed=[W, tau])
    Q.optimize(W, tau, maxiter=100, collapsed=[X, alpha])
    bpplt.pyplot.plot(np.cumsum(Q.cputime), Q.L, 'r:')

    bpplt.pyplot.show()
示例#14
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    def test_message_to_parent(self):
        """
        Test the message to parents of Mixture node.
        """

        K = 3

        # Broadcasting the moments on the cluster axis
        Mu = GaussianARD(2, 1, ndim=0, plates=(K, ))
        (mu, mumu) = Mu._message_to_child()
        Alpha = Gamma(3, 1, plates=(K, ))
        (alpha, logalpha) = Alpha._message_to_child()
        z = Categorical(np.ones(K) / K)
        X = Mixture(z, GaussianARD, Mu, Alpha)
        tau = 4
        Y = GaussianARD(X, tau)
        y = 5
        Y.observe(y)
        (x, xx) = X._message_to_child()
        m = z._message_from_children()
        self.assertAllClose(
            m[0] * np.ones(K),
            random.gaussian_logpdf(xx * alpha, x * alpha * mu, mumu * alpha,
                                   logalpha, 0) * np.ones(K))
        m = Mu._message_from_children()
        self.assertAllClose(m[0], 1 / K * (alpha * x) * np.ones(3))
        self.assertAllClose(m[1], -0.5 * 1 / K * alpha * np.ones(3))

        # Some parameters do not have cluster plate axis
        Mu = GaussianARD(2, 1, ndim=0, plates=(K, ))
        (mu, mumu) = Mu._message_to_child()
        Alpha = Gamma(3, 1)  # Note: no cluster plate axis!
        (alpha, logalpha) = Alpha._message_to_child()
        z = Categorical(np.ones(K) / K)
        X = Mixture(z, GaussianARD, Mu, Alpha)
        tau = 4
        Y = GaussianARD(X, tau)
        y = 5
        Y.observe(y)
        (x, xx) = X._message_to_child()
        m = z._message_from_children()
        self.assertAllClose(
            m[0] * np.ones(K),
            random.gaussian_logpdf(xx * alpha, x * alpha * mu, mumu * alpha,
                                   logalpha, 0) * np.ones(K))

        m = Mu._message_from_children()
        self.assertAllClose(m[0], 1 / K * (alpha * x) * np.ones(3))
        self.assertAllClose(m[1], -0.5 * 1 / K * alpha * np.ones(3))

        # Cluster assignments do not have as many plate axes as parameters.
        M = 2
        Mu = GaussianARD(2, 1, ndim=0, plates=(K, M))
        (mu, mumu) = Mu._message_to_child()
        Alpha = Gamma(3, 1, plates=(K, M))
        (alpha, logalpha) = Alpha._message_to_child()
        z = Categorical(np.ones(K) / K)
        X = Mixture(z, GaussianARD, Mu, Alpha, cluster_plate=-2)
        tau = 4
        Y = GaussianARD(X, tau)
        y = 5 * np.ones(M)
        Y.observe(y)
        (x, xx) = X._message_to_child()
        m = z._message_from_children()
        self.assertAllClose(
            m[0] * np.ones(K),
            np.sum(random.gaussian_logpdf(xx * alpha, x * alpha * mu,
                                          mumu * alpha, logalpha, 0) * np.ones(
                                              (K, M)),
                   axis=-1))

        m = Mu._message_from_children()
        self.assertAllClose(m[0] * np.ones((K, M)),
                            1 / K * (alpha * x) * np.ones((K, M)))
        self.assertAllClose(m[1] * np.ones((K, M)),
                            -0.5 * 1 / K * alpha * np.ones((K, M)))

        # Mixed distribution broadcasts g
        # This tests for a found bug. The bug caused an error.
        Z = Categorical([0.3, 0.5, 0.2])
        X = Mixture(Z, Categorical, [[0.2, 0.8], [0.1, 0.9], [0.3, 0.7]])
        m = Z._message_from_children()

        pass
示例#15
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    def test_message_to_parent(self):
        """
        Test the message to parents of Concatenate node.
        """

        # Two parents without shapes
        X1 = GaussianARD(0, 1, plates=(2,), shape=())
        X2 = GaussianARD(0, 1, plates=(3,), shape=())
        Z = Concatenate(X1, X2)
        Y = GaussianARD(Z, 1)
        Y.observe(np.random.randn(*Y.get_shape(0)))
        m1 = X1._message_from_children()
        m2 = X2._message_from_children()
        m = Z._message_from_children()
        self.assertAllClose((m[0]*np.ones((5,)))[:2],
                            m1[0]*np.ones((2,)))
        self.assertAllClose((m[1]*np.ones((5,)))[:2],
                            m1[1]*np.ones((2,)))
        self.assertAllClose((m[0]*np.ones((5,)))[2:],
                            m2[0]*np.ones((3,)))
        self.assertAllClose((m[1]*np.ones((5,)))[2:],
                            m2[1]*np.ones((3,)))

        # Two parents with shapes
        with warnings.catch_warnings():
            warnings.simplefilter("ignore", FutureWarning)

            X1 = GaussianARD(0, 1, plates=(2,), shape=(4,6))
            X2 = GaussianARD(0, 1, plates=(3,), shape=(4,6))
            Z = Concatenate(X1, X2)
            Y = GaussianARD(Z, 1)
            Y.observe(np.random.randn(*Y.get_shape(0)))
            m1 = X1._message_from_children()
            m2 = X2._message_from_children()
            m = Z._message_from_children()
            self.assertAllClose((m[0]*np.ones((5,4,6)))[:2],
                                m1[0]*np.ones((2,4,6)))
            self.assertAllClose((m[1]*np.ones((5,4,6,4,6)))[:2],
                                m1[1]*np.ones((2,4,6,4,6)))
            self.assertAllClose((m[0]*np.ones((5,4,6)))[2:],
                                m2[0]*np.ones((3,4,6)))
            self.assertAllClose((m[1]*np.ones((5,4,6,4,6)))[2:],
                                m2[1]*np.ones((3,4,6,4,6)))

            # Two parents with non-default concatenation axis
            X1 = GaussianARD(0, 1, plates=(2,4), shape=())
            X2 = GaussianARD(0, 1, plates=(3,4), shape=())
            Z = Concatenate(X1, X2, axis=-2)
            Y = GaussianARD(Z, 1)
            Y.observe(np.random.randn(*Y.get_shape(0)))
            m1 = X1._message_from_children()
            m2 = X2._message_from_children()
            m = Z._message_from_children()
            self.assertAllClose((m[0]*np.ones((5,4)))[:2],
                                m1[0]*np.ones((2,4)))
            self.assertAllClose((m[1]*np.ones((5,4)))[:2],
                                m1[1]*np.ones((2,4)))
            self.assertAllClose((m[0]*np.ones((5,4)))[2:],
                                m2[0]*np.ones((3,4)))
            self.assertAllClose((m[1]*np.ones((5,4)))[2:],
                                m2[1]*np.ones((3,4)))

            # Constant parent
            X1 = np.random.randn(2,4,6)
            X2 = GaussianARD(0, 1, plates=(3,), shape=(4,6))
            Z = Concatenate(X1, X2)
            Y = GaussianARD(Z, 1)
            Y.observe(np.random.randn(*Y.get_shape(0)))
            m1 = Z._message_to_parent(0)
            m2 = X2._message_from_children()
            m = Z._message_from_children()
            self.assertAllClose((m[0]*np.ones((5,4,6)))[:2],
                                m1[0]*np.ones((2,4,6)))
            self.assertAllClose((m[1]*np.ones((5,4,6,4,6)))[:2],
                                m1[1]*np.ones((2,4,6,4,6)))
            self.assertAllClose((m[0]*np.ones((5,4,6)))[2:],
                                m2[0]*np.ones((3,4,6)))
            self.assertAllClose((m[1]*np.ones((5,4,6,4,6)))[2:],
                                m2[1]*np.ones((3,4,6,4,6)))

        pass
示例#16
0
    def test_message_to_parent_mu(self):
        """
        Test that GaussianARD computes the message to the 1st parent correctly.
        """

        # Check formula with uncertain parent alpha
        mu = GaussianARD(0, 1)
        alpha = Gamma(2, 1)
        X = GaussianARD(mu, alpha)
        X.observe(3)
        (m0, m1) = mu._message_from_children()
        #(m0, m1) = X._message_to_parent(0)
        self.assertAllClose(m0, 2 * 3)
        self.assertAllClose(m1, -0.5 * 2)

        # Check formula with uncertain node
        mu = GaussianARD(1, 1e10)
        X = GaussianARD(mu, 2)
        Y = GaussianARD(X, 1)
        Y.observe(5)
        X.update()
        (m0, m1) = mu._message_from_children()
        self.assertAllClose(m0, 2 * 1 / (2 + 1) * (2 * 1 + 1 * 5))
        self.assertAllClose(m1, -0.5 * 2)

        # Check alpha larger than mu
        mu = GaussianARD(np.zeros((2, 3)), 1e10, shape=(2, 3))
        X = GaussianARD(mu, 2 * np.ones((3, 2, 3)))
        X.observe(3 * np.ones((3, 2, 3)))
        (m0, m1) = mu._message_from_children()
        self.assertAllClose(m0, 2 * 3 * 3 * np.ones((2, 3)))
        self.assertAllClose(m1, -0.5 * 3 * 2 * misc.identity(2, 3))

        # Check mu larger than alpha
        mu = GaussianARD(np.zeros((3, 2, 3)), 1e10, shape=(3, 2, 3))
        X = GaussianARD(mu, 2 * np.ones((2, 3)))
        X.observe(3 * np.ones((3, 2, 3)))
        (m0, m1) = mu._message_from_children()
        self.assertAllClose(m0, 2 * 3 * np.ones((3, 2, 3)))
        self.assertAllClose(m1, -0.5 * 2 * misc.identity(3, 2, 3))

        # Check node larger than mu and alpha
        mu = GaussianARD(np.zeros((2, 3)), 1e10, shape=(2, 3))
        X = GaussianARD(mu, 2 * np.ones((3, )), shape=(3, 2, 3))
        X.observe(3 * np.ones((3, 2, 3)))
        (m0, m1) = mu._message_from_children()
        self.assertAllClose(m0, 2 * 3 * 3 * np.ones((2, 3)))
        self.assertAllClose(m1, -0.5 * 2 * 3 * misc.identity(2, 3))

        # Check broadcasting of dimensions
        mu = GaussianARD(np.zeros((2, 1)), 1e10, shape=(2, 1))
        X = GaussianARD(mu, 2 * np.ones((2, 3)), shape=(2, 3))
        X.observe(3 * np.ones((2, 3)))
        (m0, m1) = mu._message_from_children()
        self.assertAllClose(m0, 2 * 3 * 3 * np.ones((2, 1)))
        self.assertAllClose(m1, -0.5 * 2 * 3 * misc.identity(2, 1))

        # Check plates for smaller mu than node
        mu = GaussianARD(0, 1, shape=(3, ), plates=(4, 1, 1))
        X = GaussianARD(mu, 2 * np.ones((3, )), shape=(2, 3), plates=(4, 5))
        X.observe(3 * np.ones((4, 5, 2, 3)))
        (m0, m1) = mu._message_from_children()
        self.assertAllClose(m0 * np.ones((4, 1, 1, 3)),
                            2 * 3 * 5 * 2 * np.ones((4, 1, 1, 3)))
        self.assertAllClose(
            m1 * np.ones((4, 1, 1, 3, 3)),
            -0.5 * 2 * 5 * 2 * misc.identity(3) * np.ones((4, 1, 1, 3, 3)))

        # Check mask
        mu = GaussianARD(np.zeros((2, 1, 3)), 1e10, shape=(3, ))
        X = GaussianARD(mu,
                        2 * np.ones((2, 4, 3)),
                        shape=(3, ),
                        plates=(
                            2,
                            4,
                        ))
        X.observe(3 * np.ones((2, 4, 3)),
                  mask=[[True, True, True, False], [False, True, False, True]])
        (m0, m1) = mu._message_from_children()
        self.assertAllClose(m0, (2 * 3 * np.ones(
            (2, 1, 3)) * np.array([[[3]], [[2]]])))
        self.assertAllClose(m1, (-0.5 * 2 * misc.identity(3) * np.ones(
            (2, 1, 1, 1)) * np.array([[[[3]]], [[[2]]]])))

        # Check mask with different shapes
        mu = GaussianARD(np.zeros((2, 1, 3)), 1e10, shape=())
        X = GaussianARD(mu,
                        2 * np.ones((2, 4, 3)),
                        shape=(3, ),
                        plates=(
                            2,
                            4,
                        ))
        mask = np.array([[True, True, True, False], [False, True, False,
                                                     True]])
        X.observe(3 * np.ones((2, 4, 3)), mask=mask)
        (m0, m1) = mu._message_from_children()
        self.assertAllClose(
            m0, 2 * 3 * np.sum(
                np.ones((2, 4, 3)) * mask[..., None], axis=-2, keepdims=True))
        self.assertAllClose(m1, (-0.5 * 2 * np.sum(
            np.ones((2, 4, 3)) * mask[..., None], axis=-2, keepdims=True)))

        # Check non-ARD Gaussian child
        mu = np.array([1, 2])
        Mu = GaussianARD(mu, 1e10, shape=(2, ))
        alpha = np.array([3, 4])
        Lambda = np.array([[1, 0.5], [0.5, 1]])
        X = GaussianARD(Mu, alpha)
        Y = Gaussian(X, Lambda)
        y = np.array([5, 6])
        Y.observe(y)
        X.update()
        (m0, m1) = Mu._message_from_children()
        mean = np.dot(np.linalg.inv(np.diag(alpha) + Lambda),
                      np.dot(np.diag(alpha), mu) + np.dot(Lambda, y))
        self.assertAllClose(m0, np.dot(np.diag(alpha), mean))
        self.assertAllClose(m1, -0.5 * np.diag(alpha))

        # Check broadcasted variable axes
        mu = GaussianARD(np.zeros(1), 1e10, shape=(1, ))
        X = GaussianARD(mu, 2, shape=(3, ))
        X.observe(3 * np.ones(3))
        (m0, m1) = mu._message_from_children()
        self.assertAllClose(m0,
                            2 * 3 * np.sum(np.ones(3), axis=-1, keepdims=True))
        self.assertAllClose(
            m1,
            -0.5 * 2 * np.sum(np.identity(3), axis=(-1, -2), keepdims=True))

        pass
示例#17
0
    def test_message_to_parent_alpha(self):
        """
        Test the message from GaussianARD the 2nd parent (alpha).
        """

        # Check formula with uncertain parent mu
        mu = GaussianARD(1, 1)
        tau = Gamma(0.5 * 1e10, 1e10)
        X = GaussianARD(mu, tau)
        X.observe(3)
        (m0, m1) = tau._message_from_children()
        self.assertAllClose(m0, -0.5 * (3**2 - 2 * 3 * 1 + 1**2 + 1))
        self.assertAllClose(m1, 0.5)

        # Check formula with uncertain node
        tau = Gamma(1e10, 1e10)
        X = GaussianARD(2, tau)
        Y = GaussianARD(X, 1)
        Y.observe(5)
        X.update()
        (m0, m1) = tau._message_from_children()
        self.assertAllClose(m0,
                            -0.5 * (1 / (1 + 1) + 3.5**2 - 2 * 3.5 * 2 + 2**2))
        self.assertAllClose(m1, 0.5)

        # Check alpha larger than mu
        alpha = Gamma(np.ones((3, 2, 3)) * 1e10, 1e10)
        X = GaussianARD(np.ones((2, 3)), alpha, ndim=3)
        X.observe(2 * np.ones((3, 2, 3)))
        (m0, m1) = alpha._message_from_children()
        self.assertAllClose(
            m0 * np.ones((3, 2, 3)),
            -0.5 * (2**2 - 2 * 2 * 1 + 1**2) * np.ones((3, 2, 3)))
        self.assertAllClose(m1 * np.ones((3, 2, 3)), 0.5 * np.ones((3, 2, 3)))

        # Check mu larger than alpha
        tau = Gamma(np.ones((2, 3)) * 1e10, 1e10)
        X = GaussianARD(np.ones((3, 2, 3)), tau, ndim=3)
        X.observe(2 * np.ones((3, 2, 3)))
        (m0, m1) = tau._message_from_children()
        self.assertAllClose(
            m0, -0.5 * (2**2 - 2 * 2 * 1 + 1**2) * 3 * np.ones((2, 3)))
        self.assertAllClose(m1 * np.ones((2, 3)), 0.5 * 3 * np.ones((2, 3)))

        # Check node larger than mu and alpha
        tau = Gamma(np.ones((3, )) * 1e10, 1e10)
        X = GaussianARD(np.ones((2, 3)), tau, shape=(3, 2, 3))
        X.observe(2 * np.ones((3, 2, 3)))
        (m0, m1) = tau._message_from_children()
        self.assertAllClose(
            m0 * np.ones(3), -0.5 * (2**2 - 2 * 2 * 1 + 1**2) * 6 * np.ones(
                (3, )))
        self.assertAllClose(m1 * np.ones(3), 0.5 * 6 * np.ones(3))

        # Check plates for smaller mu than node
        tau = Gamma(np.ones((4, 1, 2, 3)) * 1e10, 1e10)
        X = GaussianARD(GaussianARD(1, 1, shape=(3, ), plates=(4, 1, 1)),
                        tau,
                        shape=(2, 3),
                        plates=(4, 5))
        X.observe(2 * np.ones((4, 5, 2, 3)))
        (m0, m1) = tau._message_from_children()
        self.assertAllClose(m0 * np.ones(
            (4, 1, 2, 3)), (-0.5 * (2**2 - 2 * 2 * 1 + 1**2 + 1) * 5 * np.ones(
                (4, 1, 2, 3))))
        self.assertAllClose(m1 * np.ones((4, 1, 2, 3)), 5 * 0.5 * np.ones(
            (4, 1, 2, 3)))

        # Check mask
        tau = Gamma(np.ones((4, 3)) * 1e10, 1e10)
        X = GaussianARD(np.ones(3), tau, shape=(3, ), plates=(
            2,
            4,
        ))
        X.observe(2 * np.ones((2, 4, 3)),
                  mask=[[True, False, True, False], [False, True, True,
                                                     False]])
        (m0, m1) = tau._message_from_children()
        self.assertAllClose(m0 * np.ones((4, 3)),
                            (-0.5 * (2**2 - 2 * 2 * 1 + 1**2) * np.ones(
                                (4, 3)) * np.array([[1], [1], [2], [0]])))
        self.assertAllClose(
            m1 * np.ones((4, 3)),
            0.5 * np.array([[1], [1], [2], [0]]) * np.ones((4, 3)))

        # Check non-ARD Gaussian child
        mu = np.array([1, 2])
        alpha = np.array([3, 4])
        Alpha = Gamma(alpha * 1e10, 1e10)
        Lambda = np.array([[1, 0.5], [0.5, 1]])
        X = GaussianARD(mu, Alpha, ndim=1)
        Y = Gaussian(X, Lambda)
        y = np.array([5, 6])
        Y.observe(y)
        X.update()
        (m0, m1) = Alpha._message_from_children()
        Cov = np.linalg.inv(np.diag(alpha) + Lambda)
        mean = np.dot(Cov, np.dot(np.diag(alpha), mu) + np.dot(Lambda, y))
        self.assertAllClose(
            m0 * np.ones(2), -0.5 * np.diag(
                np.outer(mean, mean) + Cov - np.outer(mean, mu) -
                np.outer(mu, mean) + np.outer(mu, mu)))
        self.assertAllClose(m1 * np.ones(2), 0.5 * np.ones(2))

        pass
示例#18
0
import numpy
numpy.random.seed(1)
M = 20
N = 100
import numpy as np
x = np.random.randn(N, 2)
w = np.random.randn(M, 2)
f = np.einsum('ik,jk->ij', w, x)
y = f + 0.1 * np.random.randn(M, N)
D = 10
from bayespy.nodes import GaussianARD, Gamma, SumMultiply
X = GaussianARD(0, 1, plates=(1, N), shape=(D, ))
alpha = Gamma(1e-5, 1e-5, plates=(D, ))
C = GaussianARD(0, alpha, plates=(M, 1), shape=(D, ))
F = SumMultiply('d,d->', X, C)
tau = Gamma(1e-5, 1e-5)
Y = GaussianARD(F, tau)
Y.observe(y)
from bayespy.inference import VB
Q = VB(Y, X, C, alpha, tau)
C.initialize_from_random()
from bayespy.inference.vmp.transformations import RotateGaussianARD
rot_X = RotateGaussianARD(X)
rot_C = RotateGaussianARD(C, alpha)
from bayespy.inference.vmp.transformations import RotationOptimizer
R = RotationOptimizer(rot_X, rot_C, D)
Q.set_callback(R.rotate)
Q.update(repeat=1000)
import bayespy.plot as bpplt
bpplt.plot(F)
bpplt.plot(f, color='r', marker='x', linestyle='None')
示例#19
0
import numpy as np

np.random.seed(1)
data = np.random.normal(5, 10, size=(10, ))
from bayespy.nodes import GaussianARD, Gamma

mu = GaussianARD(0, 1e-6)
tau = Gamma(1e-6, 1e-6)
y = GaussianARD(mu, tau, plates=(10, ))
y.observe(data)
from bayespy.inference import VB

Q = VB(mu, tau, y)
Q.update(repeat=20)
import bayespy.plot as bpplt

bpplt.pyplot.subplot(2, 1, 1)
bpplt.pdf(mu, np.linspace(-10, 20, num=100), color='k', name=r'\mu')
bpplt.pyplot.subplot(2, 1, 2)
bpplt.pdf(tau, np.linspace(1e-6, 0.08, num=100), color='k', name=r'\tau')
bpplt.pyplot.tight_layout()
bpplt.pyplot.show()
示例#20
0
    def test_message_to_parent_alpha(self):
        """
        Test the message from GaussianARD the 2nd parent (alpha).
        """

        # Check formula with uncertain parent mu
        mu = GaussianARD(1,1)
        tau = Gamma(0.5*1e10, 1e10)
        X = GaussianARD(mu,
                        tau)
        X.observe(3)
        (m0, m1) = tau._message_from_children()
        self.assertAllClose(m0,
                            -0.5*(3**2 - 2*3*1 + 1**2+1))
        self.assertAllClose(m1,
                            0.5)

        # Check formula with uncertain node
        tau = Gamma(1e10, 1e10)
        X = GaussianARD(2, tau)
        Y = GaussianARD(X, 1)
        Y.observe(5)
        X.update()
        (m0, m1) = tau._message_from_children()
        self.assertAllClose(m0,
                            -0.5*(1/(1+1)+3.5**2 - 2*3.5*2 + 2**2))
        self.assertAllClose(m1,
                            0.5)

        # Check alpha larger than mu
        alpha = Gamma(np.ones((3,2,3))*1e10, 1e10)
        X = GaussianARD(np.ones((2,3)),
                        alpha,
                        ndim=3)
        X.observe(2*np.ones((3,2,3)))
        (m0, m1) = alpha._message_from_children()
        self.assertAllClose(m0 * np.ones((3,2,3)),
                            -0.5*(2**2 - 2*2*1 + 1**2) * np.ones((3,2,3)))
        self.assertAllClose(m1*np.ones((3,2,3)),
                            0.5*np.ones((3,2,3)))

        # Check mu larger than alpha
        tau = Gamma(np.ones((2,3))*1e10, 1e10)
        X = GaussianARD(np.ones((3,2,3)),
                        tau,
                        ndim=3)
        X.observe(2*np.ones((3,2,3)))
        (m0, m1) = tau._message_from_children()
        self.assertAllClose(m0,
                            -0.5*(2**2 - 2*2*1 + 1**2) * 3 * np.ones((2,3)))
        self.assertAllClose(m1 * np.ones((2,3)),
                            0.5 * 3 * np.ones((2,3)))

        # Check node larger than mu and alpha
        tau = Gamma(np.ones((3,))*1e10, 1e10)
        X = GaussianARD(np.ones((2,3)),
                        tau,
                        shape=(3,2,3))
        X.observe(2*np.ones((3,2,3)))
        (m0, m1) = tau._message_from_children()
        self.assertAllClose(m0 * np.ones(3),
                            -0.5*(2**2 - 2*2*1 + 1**2) * 6 * np.ones((3,)))
        self.assertAllClose(m1 * np.ones(3),
                            0.5 * 6 * np.ones(3))

        # Check plates for smaller mu than node
        tau = Gamma(np.ones((4,1,2,3))*1e10, 1e10)
        X = GaussianARD(GaussianARD(1, 1, 
                                    shape=(3,),
                                    plates=(4,1,1)),
                        tau,
                        shape=(2,3),
                        plates=(4,5))
        X.observe(2*np.ones((4,5,2,3)))
        (m0, m1) = tau._message_from_children()
        self.assertAllClose(m0 * np.ones((4,1,2,3)),
                            (-0.5 * (2**2 - 2*2*1 + 1**2+1)
                             * 5*np.ones((4,1,2,3))))
        self.assertAllClose(m1 * np.ones((4,1,2,3)),
                            5*0.5 * np.ones((4,1,2,3)))

        # Check mask
        tau = Gamma(np.ones((4,3))*1e10, 1e10)
        X = GaussianARD(np.ones(3),
                        tau,
                        shape=(3,),
                        plates=(2,4,))
        X.observe(2*np.ones((2,4,3)), mask=[[True, False, True, False],
                                            [False, True, True, False]])
        (m0, m1) = tau._message_from_children()
        self.assertAllClose(m0 * np.ones((4,3)),
                            (-0.5 * (2**2 - 2*2*1 + 1**2) 
                             * np.ones((4,3)) 
                             * np.array([[1], [1], [2], [0]])))
        self.assertAllClose(m1 * np.ones((4,3)),
                            0.5 * np.array([[1], [1], [2], [0]]) * np.ones((4,3)))
        
        # Check non-ARD Gaussian child
        mu = np.array([1,2])
        alpha = np.array([3,4])
        Alpha = Gamma(alpha*1e10, 1e10)
        Lambda = np.array([[1, 0.5],
                          [0.5, 1]])
        X = GaussianARD(mu, Alpha, ndim=1)
        Y = Gaussian(X, Lambda)
        y = np.array([5,6])
        Y.observe(y)
        X.update()
        (m0, m1) = Alpha._message_from_children()
        Cov = np.linalg.inv(np.diag(alpha)+Lambda)
        mean = np.dot(Cov, np.dot(np.diag(alpha), mu)
                           + np.dot(Lambda, y))
        self.assertAllClose(m0 * np.ones(2),
                            -0.5 * np.diag(
                                np.outer(mean, mean) + Cov
                                - np.outer(mean, mu)
                                - np.outer(mu, mean)
                                + np.outer(mu, mu)))
        self.assertAllClose(m1 * np.ones(2),
                            0.5 * np.ones(2))
        
        pass
示例#21
0
    def test_message_to_parent(self):
        """
        Test the message to parents of Gate node.
        """

        # Unobserved and broadcasting
        Z = 2
        X = GaussianARD(0, 1, shape=(), plates=(3,))
        F = Gate(Z, X)
        Y = GaussianARD(F, 1)
        m = F._message_to_parent(0)
        self.assertEqual(len(m), 1)
        self.assertAllClose(m[0], 0*np.ones(3))
        m = F._message_to_parent(1)
        self.assertEqual(len(m), 2)
        self.assertAllClose(m[0]*np.ones(3), [0, 0, 0])
        self.assertAllClose(m[1]*np.ones(3), [0, 0, 0])
        
        # Gating scalar node
        Z = 2
        X = GaussianARD([1,2,3], 1, shape=(), plates=(3,))
        F = Gate(Z, X)
        Y = GaussianARD(F, 1)
        Y.observe(10)
        m = F._message_to_parent(0)
        self.assertAllClose(m[0], [10*1-0.5*2, 10*2-0.5*5, 10*3-0.5*10])
        m = F._message_to_parent(1)
        self.assertAllClose(m[0], [0, 0, 10])
        self.assertAllClose(m[1], [0, 0, -0.5])
        
        # Fixed X
        Z = 2
        X = [1,2,3]
        F = Gate(Z, X, moments=GaussianMoments(0))
        Y = GaussianARD(F, 1)
        Y.observe(10)
        m = F._message_to_parent(0)
        self.assertAllClose(m[0], [10*1-0.5*1, 10*2-0.5*4, 10*3-0.5*9])
        m = F._message_to_parent(1)
        self.assertAllClose(m[0], [0, 0, 10])
        self.assertAllClose(m[1], [0, 0, -0.5])

        # Uncertain gating
        Z = Categorical([0.2, 0.3, 0.5])
        X = GaussianARD([1,2,3], 1, shape=(), plates=(3,))
        F = Gate(Z, X)
        Y = GaussianARD(F, 1)
        Y.observe(10)
        m = F._message_to_parent(0)
        self.assertAllClose(m[0], [10*1-0.5*2, 10*2-0.5*5, 10*3-0.5*10])
        m = F._message_to_parent(1)
        self.assertAllClose(m[0], [0.2*10, 0.3*10, 0.5*10])
        self.assertAllClose(m[1], [-0.5*0.2, -0.5*0.3, -0.5*0.5])

        # Plates in Z
        Z = [2, 0]
        X = GaussianARD([1,2,3], 1, shape=(), plates=(3,))
        F = Gate(Z, X)
        Y = GaussianARD(F, 1)
        Y.observe([10, 20])
        m = F._message_to_parent(0)
        self.assertAllClose(m[0], [[10*1-0.5*2, 10*2-0.5*5, 10*3-0.5*10],
                                   [20*1-0.5*2, 20*2-0.5*5, 20*3-0.5*10]])
        m = F._message_to_parent(1)
        self.assertAllClose(m[0], [20, 0, 10])
        self.assertAllClose(m[1], [-0.5, 0, -0.5])

        # Plates in X
        Z = 2
        X = GaussianARD([[1,2,3], [4,5,6]], 1, shape=(), plates=(2,3,))
        F = Gate(Z, X)
        Y = GaussianARD(F, 1)
        Y.observe([10, 20])
        m = F._message_to_parent(0)
        self.assertAllClose(m[0], [10*1-0.5*2 + 20*4-0.5*17,
                                   10*2-0.5*5 + 20*5-0.5*26,
                                   10*3-0.5*10 + 20*6-0.5*37])
        m = F._message_to_parent(1)
        self.assertAllClose(m[0], [[0, 0, 10],
                                   [0, 0, 20]])
        self.assertAllClose(m[1]*np.ones((2,3)), [[0, 0, -0.5],
                                                  [0, 0, -0.5]])

        # Gating non-default plate
        Z = 2
        X = GaussianARD([[1],[2],[3]], 1, shape=(), plates=(3,1))
        F = Gate(Z, X, gated_plate=-2)
        Y = GaussianARD(F, 1)
        Y.observe([10])
        m = F._message_to_parent(0)
        self.assertAllClose(m[0], [10*1-0.5*2, 10*2-0.5*5, 10*3-0.5*10])
        m = F._message_to_parent(1)
        self.assertAllClose(m[0], [[0], [0], [10]])
        self.assertAllClose(m[1], [[0], [0], [-0.5]])

        # Gating non-scalar node
        Z = 2
        X = GaussianARD([[1,4],[2,5],[3,6]], 1, shape=(2,), plates=(3,))
        F = Gate(Z, X)
        Y = GaussianARD(F, 1)
        Y.observe([10,20])
        m = F._message_to_parent(0)
        self.assertAllClose(m[0], [10*1-0.5*2 + 20*4-0.5*17,
                                   10*2-0.5*5 + 20*5-0.5*26,
                                   10*3-0.5*10 + 20*6-0.5*37])
        m = F._message_to_parent(1)
        I = np.identity(2)
        self.assertAllClose(m[0], [[0,0], [0,0], [10,20]])
        self.assertAllClose(m[1], [0*I, 0*I, -0.5*I])
        
        # Broadcasting the moments on the cluster axis
        Z = 2
        X = GaussianARD(2, 1, shape=(), plates=(3,))
        F = Gate(Z, X)
        Y = GaussianARD(F, 1)
        Y.observe(10)
        m = F._message_to_parent(0)
        self.assertAllClose(m[0], [10*2-0.5*5, 10*2-0.5*5, 10*2-0.5*5])
        m = F._message_to_parent(1)
        self.assertAllClose(m[0], [0, 0, 10])
        self.assertAllClose(m[1], [0, 0, -0.5])

        pass
示例#22
0
    def test_message_to_child(self):
        """
        Test moments of GaussianARD.
        """

        # Check that moments have full shape when broadcasting
        X = GaussianARD(np.zeros((2,)),
                        np.ones((3,2)),
                        shape=(4,3,2))
        (u0, u1) = X._message_to_child()
        self.assertEqual(np.shape(u0),
                         (4,3,2))
        self.assertEqual(np.shape(u1),
                         (4,3,2,4,3,2))

        # Check the formula
        X = GaussianARD(2, 3)
        (u0, u1) = X._message_to_child()
        self.assertAllClose(u0, 2)
        self.assertAllClose(u1, 2**2 + 1/3)

        # Check the formula for multidimensional arrays
        X = GaussianARD(2*np.ones((2,1,4)),
                        3*np.ones((2,3,1)),
                        ndim=3)
        (u0, u1) = X._message_to_child()
        self.assertAllClose(u0, 2*np.ones((2,3,4)))
        self.assertAllClose(u1, 
                            2**2 * np.ones((2,3,4,2,3,4))
                            + 1/3 * misc.identity(2,3,4))
                            

        # Check the formula for dim-broadcasted mu
        X = GaussianARD(2*np.ones((3,1)),
                        3*np.ones((2,3,4)),
                        ndim=3)
        (u0, u1) = X._message_to_child()
        self.assertAllClose(u0, 2*np.ones((2,3,4)))
        self.assertAllClose(u1, 
                            2**2 * np.ones((2,3,4,2,3,4))
                            + 1/3 * misc.identity(2,3,4))
                            
        # Check the formula for dim-broadcasted alpha
        X = GaussianARD(2*np.ones((2,3,4)),
                        3*np.ones((3,1)),
                        ndim=3)
        (u0, u1) = X._message_to_child()
        self.assertAllClose(u0, 2*np.ones((2,3,4)))
        self.assertAllClose(u1, 
                            2**2 * np.ones((2,3,4,2,3,4))
                            + 1/3 * misc.identity(2,3,4))
                            
        # Check the formula for dim-broadcasted mu and alpha
        X = GaussianARD(2*np.ones((3,1)),
                        3*np.ones((3,1)),
                        shape=(2,3,4))
        (u0, u1) = X._message_to_child()
        self.assertAllClose(u0, 2*np.ones((2,3,4)))
        self.assertAllClose(u1, 
                            2**2 * np.ones((2,3,4,2,3,4))
                            + 1/3 * misc.identity(2,3,4))
                            
        # Check the formula for dim-broadcasted mu with plates
        mu = GaussianARD(2*np.ones((5,1,3,4)),
                         np.ones((5,1,3,4)),
                         shape=(3,4),
                         plates=(5,1))
        X = GaussianARD(mu,
                        3*np.ones((5,2,3,4)),
                        shape=(2,3,4),
                        plates=(5,))
        (u0, u1) = X._message_to_child()
        self.assertAllClose(u0, 2*np.ones((5,2,3,4)))
        self.assertAllClose(u1, 
                            2**2 * np.ones((5,2,3,4,2,3,4))
                            + 1/3 * misc.identity(2,3,4))

        # Check posterior
        X = GaussianARD(2, 3)
        Y = GaussianARD(X, 1)
        Y.observe(10)
        X.update()
        (u0, u1) = X._message_to_child()
        self.assertAllClose(u0,
                            1/(3+1) * (3*2 + 1*10))
        self.assertAllClose(u1,
                            (1/(3+1) * (3*2 + 1*10))**2 + 1/(3+1))
        
        pass
示例#23
0
    def test_message_to_parent_mu(self):
        """
        Test that GaussianARD computes the message to the 1st parent correctly.
        """

        # Check formula with uncertain parent alpha
        mu = GaussianARD(0, 1)
        alpha = Gamma(2,1)
        X = GaussianARD(mu,
                        alpha)
        X.observe(3)
        (m0, m1) = mu._message_from_children()
        #(m0, m1) = X._message_to_parent(0)
        self.assertAllClose(m0,
                            2*3)
        self.assertAllClose(m1,
                            -0.5*2)

        # Check formula with uncertain node
        mu = GaussianARD(1, 1e10)
        X = GaussianARD(mu, 2)
        Y = GaussianARD(X, 1)
        Y.observe(5)
        X.update()
        (m0, m1) = mu._message_from_children()
        self.assertAllClose(m0,
                            2 * 1/(2+1)*(2*1+1*5))
        self.assertAllClose(m1,
                            -0.5*2)

        # Check alpha larger than mu
        mu = GaussianARD(np.zeros((2,3)), 1e10, shape=(2,3))
        X = GaussianARD(mu,
                        2*np.ones((3,2,3)))
        X.observe(3*np.ones((3,2,3)))
        (m0, m1) = mu._message_from_children()
        self.assertAllClose(m0,
                            2*3 * 3 * np.ones((2,3)))
        self.assertAllClose(m1,
                            -0.5 * 3 * 2*misc.identity(2,3))

        # Check mu larger than alpha
        mu = GaussianARD(np.zeros((3,2,3)), 1e10, shape=(3,2,3))
        X = GaussianARD(mu,
                        2*np.ones((2,3)))
        X.observe(3*np.ones((3,2,3)))
        (m0, m1) = mu._message_from_children()
        self.assertAllClose(m0,
                            2 * 3 * np.ones((3,2,3)))
        self.assertAllClose(m1,
                            -0.5 * 2*misc.identity(3,2,3))

        # Check node larger than mu and alpha
        mu = GaussianARD(np.zeros((2,3)), 1e10, shape=(2,3))
        X = GaussianARD(mu,
                        2*np.ones((3,)),
                        shape=(3,2,3))
        X.observe(3*np.ones((3,2,3)))
        (m0, m1) = mu._message_from_children()
        self.assertAllClose(m0,
                            2*3 * 3*np.ones((2,3)))
        self.assertAllClose(m1,
                            -0.5 * 2 * 3*misc.identity(2,3))

        # Check broadcasting of dimensions
        mu = GaussianARD(np.zeros((2,1)), 1e10, shape=(2,1))
        X = GaussianARD(mu,
                        2*np.ones((2,3)),
                        shape=(2,3))
        X.observe(3*np.ones((2,3)))
        (m0, m1) = mu._message_from_children()
        self.assertAllClose(m0,
                            2*3 * 3*np.ones((2,1)))
        self.assertAllClose(m1,
                            -0.5 * 2 * 3*misc.identity(2,1))

        # Check plates for smaller mu than node
        mu = GaussianARD(0,1, 
                         shape=(3,),
                         plates=(4,1,1))
        X = GaussianARD(mu,
                        2*np.ones((3,)),
                        shape=(2,3),
                        plates=(4,5))
        X.observe(3*np.ones((4,5,2,3)))
        (m0, m1) = mu._message_from_children()
        self.assertAllClose(m0 * np.ones((4,1,1,3)),
                            2*3 * 5*2*np.ones((4,1,1,3)))
        self.assertAllClose(m1 * np.ones((4,1,1,3,3)),
                            -0.5*2 * 5*2*misc.identity(3) * np.ones((4,1,1,3,3)))

        # Check mask
        mu = GaussianARD(np.zeros((2,1,3)), 1e10, shape=(3,))
        X = GaussianARD(mu,
                        2*np.ones((2,4,3)),
                        shape=(3,),
                        plates=(2,4,))
        X.observe(3*np.ones((2,4,3)), mask=[[True, True, True, False],
                                            [False, True, False, True]])
        (m0, m1) = mu._message_from_children()
        self.assertAllClose(m0,
                            (2*3 * np.ones((2,1,3)) 
                             * np.array([[[3]], [[2]]])))
        self.assertAllClose(m1,
                            (-0.5*2 * misc.identity(3)
                             * np.ones((2,1,1,1))
                             * np.array([[[[3]]], [[[2]]]])))

        # Check mask with different shapes
        mu = GaussianARD(np.zeros((2,1,3)), 1e10, shape=())
        X = GaussianARD(mu,
                        2*np.ones((2,4,3)),
                        shape=(3,),
                        plates=(2,4,))
        mask = np.array([[True, True, True, False],
                         [False, True, False, True]])
        X.observe(3*np.ones((2,4,3)), mask=mask)
        (m0, m1) = mu._message_from_children()
        self.assertAllClose(m0,
                            2*3 * np.sum(np.ones((2,4,3))*mask[...,None], 
                                         axis=-2,
                                         keepdims=True))
        self.assertAllClose(m1,
                            (-0.5*2 * np.sum(np.ones((2,4,3))*mask[...,None],
                                             axis=-2,
                                             keepdims=True)))

        # Check non-ARD Gaussian child
        mu = np.array([1,2])
        Mu = GaussianARD(mu, 1e10, shape=(2,))
        alpha = np.array([3,4])
        Lambda = np.array([[1, 0.5],
                          [0.5, 1]])
        X = GaussianARD(Mu, alpha, ndim=1)
        Y = Gaussian(X, Lambda)
        y = np.array([5,6])
        Y.observe(y)
        X.update()
        (m0, m1) = Mu._message_from_children()
        mean = np.dot(np.linalg.inv(np.diag(alpha)+Lambda),
                      np.dot(np.diag(alpha), mu)
                      + np.dot(Lambda, y))
        self.assertAllClose(m0,
                            np.dot(np.diag(alpha), mean))
        self.assertAllClose(m1,
                            -0.5*np.diag(alpha))

        # Check broadcasted variable axes
        mu = GaussianARD(np.zeros(1), 1e10, shape=(1,))
        X = GaussianARD(mu,
                        2,
                        shape=(3,))
        X.observe(3*np.ones(3))
        (m0, m1) = mu._message_from_children()
        self.assertAllClose(m0,
                            2*3 * np.sum(np.ones(3), axis=-1, keepdims=True))
        self.assertAllClose(m1,
                            -0.5*2 * np.sum(np.identity(3), 
                                            axis=(-1,-2), 
                                            keepdims=True))

        pass
示例#24
0
    def test_message_to_parent(self):
        """
        Test the message to parents of Mixture node.
        """

        K = 3

        # Broadcasting the moments on the cluster axis
        Mu = GaussianARD(2, 1,
                         ndim=0,
                         plates=(K,))
        (mu, mumu) = Mu._message_to_child()
        Alpha = Gamma(3, 1,
                      plates=(K,))
        (alpha, logalpha) = Alpha._message_to_child()
        z = Categorical(np.ones(K)/K)
        X = Mixture(z, GaussianARD, Mu, Alpha)
        tau = 4
        Y = GaussianARD(X, tau)
        y = 5
        Y.observe(y)
        (x, xx) = X._message_to_child()
        m = z._message_from_children()
        self.assertAllClose(m[0] * np.ones(K),
                            random.gaussian_logpdf(xx*alpha,
                                                   x*alpha*mu,
                                                   mumu*alpha,
                                                   logalpha,
                                                   0)
                            * np.ones(K))
        m = Mu._message_from_children()
        self.assertAllClose(m[0],
                            1/K * (alpha*x) * np.ones(3))
        self.assertAllClose(m[1],
                            -0.5 * 1/K * alpha * np.ones(3))

        # Some parameters do not have cluster plate axis
        Mu = GaussianARD(2, 1,
                         ndim=0,
                         plates=(K,))
        (mu, mumu) = Mu._message_to_child()
        Alpha = Gamma(3, 1) # Note: no cluster plate axis!
        (alpha, logalpha) = Alpha._message_to_child()
        z = Categorical(np.ones(K)/K)
        X = Mixture(z, GaussianARD, Mu, Alpha)
        tau = 4
        Y = GaussianARD(X, tau)
        y = 5
        Y.observe(y)
        (x, xx) = X._message_to_child()
        m = z._message_from_children()
        self.assertAllClose(m[0] * np.ones(K),
                            random.gaussian_logpdf(xx*alpha,
                                                   x*alpha*mu,
                                                   mumu*alpha,
                                                   logalpha,
                                                   0)
                            * np.ones(K))
                                                   
        m = Mu._message_from_children()
        self.assertAllClose(m[0],
                            1/K * (alpha*x) * np.ones(3))
        self.assertAllClose(m[1],
                            -0.5 * 1/K * alpha * np.ones(3))

        # Cluster assignments do not have as many plate axes as parameters.
        M = 2
        Mu = GaussianARD(2, 1,
                         ndim=0,
                         plates=(K,M))
        (mu, mumu) = Mu._message_to_child()
        Alpha = Gamma(3, 1,
                      plates=(K,M))
        (alpha, logalpha) = Alpha._message_to_child()
        z = Categorical(np.ones(K)/K)
        X = Mixture(z, GaussianARD, Mu, Alpha, cluster_plate=-2)
        tau = 4
        Y = GaussianARD(X, tau)
        y = 5 * np.ones(M)
        Y.observe(y)
        (x, xx) = X._message_to_child()
        m = z._message_from_children()
        self.assertAllClose(m[0]*np.ones(K),
                            np.sum(random.gaussian_logpdf(xx*alpha,
                                                          x*alpha*mu,
                                                          mumu*alpha,
                                                          logalpha,
                                                          0) *
                                   np.ones((K,M)),
                                   axis=-1))
                                                   
        m = Mu._message_from_children()
        self.assertAllClose(m[0] * np.ones((K,M)),
                            1/K * (alpha*x) * np.ones((K,M)))
        self.assertAllClose(m[1] * np.ones((K,M)),
                            -0.5 * 1/K * alpha * np.ones((K,M)))
        

        # Mixed distribution broadcasts g
        # This tests for a found bug. The bug caused an error.
        Z = Categorical([0.3, 0.5, 0.2])
        X = Mixture(Z, Categorical, [[0.2,0.8], [0.1,0.9], [0.3,0.7]])
        m = Z._message_from_children()

        #
        # Test nested mixtures
        #
        t1 = [1, 1, 0, 3, 3]
        t2 = [2]
        p = Dirichlet([1, 1], plates=(4, 3))
        X = Mixture(t1, Mixture, t2, Categorical, p)
        X.observe([1, 1, 0, 0, 0])
        p.update()
        self.assertAllClose(
            p.phi[0],
            [
                [[1, 1], [1, 1], [2, 1]],
                [[1, 1], [1, 1], [1, 3]],
                [[1, 1], [1, 1], [1, 1]],
                [[1, 1], [1, 1], [3, 1]],
            ]
        )

        # Test sample plates in nested mixtures
        t1 = Categorical([0.3, 0.7], plates=(5,))
        t2 = [[1], [1], [0], [3], [3]]
        t3 = 2
        p = Dirichlet([1, 1], plates=(2, 4, 3))
        X = Mixture(t1, Mixture, t2, Mixture, t3, Categorical, p)
        X.observe([1, 1, 0, 0, 0])
        p.update()
        self.assertAllClose(
            p.phi[0],
            [
                [
                    [[1, 1], [1, 1], [1.3, 1]],
                    [[1, 1], [1, 1], [1, 1.6]],
                    [[1, 1], [1, 1], [1, 1]],
                    [[1, 1], [1, 1], [1.6, 1]],
                ],
                [
                    [[1, 1], [1, 1], [1.7, 1]],
                    [[1, 1], [1, 1], [1, 2.4]],
                    [[1, 1], [1, 1], [1, 1]],
                    [[1, 1], [1, 1], [2.4, 1]],
                ]
            ]
        )

        # Check that Gate and nested Mixture are equal
        t1 = Categorical([0.3, 0.7], plates=(5,))
        t2 = Categorical([0.1, 0.3, 0.6], plates=(5, 1))
        p = Dirichlet([1, 2, 3, 4], plates=(2, 3))
        X = Mixture(t1, Mixture, t2, Categorical, p)
        X.observe([3, 3, 1, 2, 2])
        t1_msg = t1._message_from_children()
        t2_msg = t2._message_from_children()
        p_msg = p._message_from_children()
        t1 = Categorical([0.3, 0.7], plates=(5,))
        t2 = Categorical([0.1, 0.3, 0.6], plates=(5, 1))
        p = Dirichlet([1, 2, 3, 4], plates=(2, 3))
        X = Categorical(Gate(t1, Gate(t2, p)))
        X.observe([3, 3, 1, 2, 2])
        t1_msg2 = t1._message_from_children()
        t2_msg2 = t2._message_from_children()
        p_msg2 = p._message_from_children()
        self.assertAllClose(t1_msg[0], t1_msg2[0])
        self.assertAllClose(t2_msg[0], t2_msg2[0])
        self.assertAllClose(p_msg[0], p_msg2[0])

        pass
示例#25
0
    def test_message_to_parent(self):
        """
        Test the message to parents of Mixture node.
        """

        K = 3

        # Broadcasting the moments on the cluster axis
        Mu = GaussianARD(2, 1,
                         ndim=0,
                         plates=(K,))
        (mu, mumu) = Mu._message_to_child()
        Alpha = Gamma(3, 1,
                      plates=(K,))
        (alpha, logalpha) = Alpha._message_to_child()
        z = Categorical(np.ones(K)/K)
        X = Mixture(z, GaussianARD, Mu, Alpha)
        tau = 4
        Y = GaussianARD(X, tau)
        y = 5
        Y.observe(y)
        (x, xx) = X._message_to_child()
        m = z._message_from_children()
        self.assertAllClose(m[0] * np.ones(K),
                            random.gaussian_logpdf(xx*alpha,
                                                   x*alpha*mu,
                                                   mumu*alpha,
                                                   logalpha,
                                                   0)
                            * np.ones(K))
        m = Mu._message_from_children()
        self.assertAllClose(m[0],
                            1/K * (alpha*x) * np.ones(3))
        self.assertAllClose(m[1],
                            -0.5 * 1/K * alpha * np.ones(3))

        # Some parameters do not have cluster plate axis
        Mu = GaussianARD(2, 1,
                         ndim=0,
                         plates=(K,))
        (mu, mumu) = Mu._message_to_child()
        Alpha = Gamma(3, 1) # Note: no cluster plate axis!
        (alpha, logalpha) = Alpha._message_to_child()
        z = Categorical(np.ones(K)/K)
        X = Mixture(z, GaussianARD, Mu, Alpha)
        tau = 4
        Y = GaussianARD(X, tau)
        y = 5
        Y.observe(y)
        (x, xx) = X._message_to_child()
        m = z._message_from_children()
        self.assertAllClose(m[0] * np.ones(K),
                            random.gaussian_logpdf(xx*alpha,
                                                   x*alpha*mu,
                                                   mumu*alpha,
                                                   logalpha,
                                                   0)
                            * np.ones(K))
                                                   
        m = Mu._message_from_children()
        self.assertAllClose(m[0],
                            1/K * (alpha*x) * np.ones(3))
        self.assertAllClose(m[1],
                            -0.5 * 1/K * alpha * np.ones(3))

        # Cluster assignments do not have as many plate axes as parameters.
        M = 2
        Mu = GaussianARD(2, 1,
                         ndim=0,
                         plates=(K,M))
        (mu, mumu) = Mu._message_to_child()
        Alpha = Gamma(3, 1,
                      plates=(K,M))
        (alpha, logalpha) = Alpha._message_to_child()
        z = Categorical(np.ones(K)/K)
        X = Mixture(z, GaussianARD, Mu, Alpha, cluster_plate=-2)
        tau = 4
        Y = GaussianARD(X, tau)
        y = 5 * np.ones(M)
        Y.observe(y)
        (x, xx) = X._message_to_child()
        m = z._message_from_children()
        self.assertAllClose(m[0]*np.ones(K),
                            np.sum(random.gaussian_logpdf(xx*alpha,
                                                          x*alpha*mu,
                                                          mumu*alpha,
                                                          logalpha,
                                                          0) *
                                   np.ones((K,M)),
                                   axis=-1))
                                                   
        m = Mu._message_from_children()
        self.assertAllClose(m[0] * np.ones((K,M)),
                            1/K * (alpha*x) * np.ones((K,M)))
        self.assertAllClose(m[1] * np.ones((K,M)),
                            -0.5 * 1/K * alpha * np.ones((K,M)))
        

        # Mixed distribution broadcasts g
        # This tests for a found bug. The bug caused an error.
        Z = Categorical([0.3, 0.5, 0.2])
        X = Mixture(Z, Categorical, [[0.2,0.8], [0.1,0.9], [0.3,0.7]])
        m = Z._message_from_children()

        pass
# 各ノードを定義
X = GaussianARD(0, 1, shape=(D, ), plates=(1, 100), name='X')
alpha = Gamma(1e-3, 1e-3, plates=(D, ), name='alpha')
C = GaussianARD(0, alpha, shape=(D, ), plates=(10, 1), name='C')
F = Dot(C, X)  #内積
tau = Gamma(1e-3, 1e-3, name='tau')
Y = GaussianARD(F, tau, name='Y')

# -----Performing inference------
# 1: Observe some nodes
c = np.random.randn(10, 2)
x = np.random.randn(2, 100)
data = np.dot(c, x) + 0.1 * np.random.randn(10, 100)
# data:10×100

Y.observe(data)
#( Missing values)
Y.observe(data,
          mask=[[True], [False], [False], [True], [True], [False], [True],
                [True], [True], [False]])

# 2: Choosing the inference method
from bayespy.inference import VB
Q = VB(Y, C, X, alpha, tau)

# 3: Initializing the posterior approximation
X.initialize_from_parameters(np.random.randn(1, 100, D), 10)

# 4: Running the inference algorithm
# Q.update()
# Q.update(C, X)
示例#27
0
        def check(indices, plates, shape, axis=-1, use_mask=False):
            mu = np.random.rand(*(plates+shape))
            alpha = np.random.rand(*(plates+shape))
            X = GaussianARD(mu, alpha, shape=shape, plates=plates)
            Y = Take(X, indices, plate_axis=axis)
            Z = GaussianARD(Y, 1, shape=shape)
            z = np.random.randn(*(Z.get_shape(0)))
            if use_mask:
                mask = np.mod(np.reshape(np.arange(np.prod(Z.plates)), Z.plates), 2) != 0
            else:
                mask = True
            Z.observe(z, mask=mask)
            X.update()
            (x0, x1) = X.get_moments()

            # For comparison, build the same model brute force
            X = GaussianARD(mu, alpha, shape=shape, plates=plates)

            # Number of trailing plate axes before the take axis
            N = len(X.plates) + axis

            # Reshape the take axes into a single axis
            z_shape = X.plates[:axis] + (-1,)
            if axis < -1:
                z_shape = z_shape + X.plates[(axis+1):]
            z_shape = z_shape + shape
            z = np.reshape(z, z_shape)

            # Reshape the take axes into a single axis
            if use_mask:
                mask_shape = X.plates[:axis] + (-1,)
                if axis < -1:
                    mask_shape = mask_shape + X.plates[(axis+1):]
                mask = np.reshape(mask, mask_shape)

            for (j, i) in enumerate(range(np.size(indices))):
                ind = np.array(indices).flatten()[i]
                index_x = N*(slice(None),) + (ind,)
                index_z = N*(slice(None),) + (j,)
                # print(index)
                Xi = X[index_x]
                zi = z[index_z]
                Zi = GaussianARD(Xi, 1, ndim=len(shape))
                if use_mask:
                    maski = mask[index_z]
                else:
                    maski = True
                Zi.observe(zi, mask=maski)

            X.update()

            self.assertAllClose(
                x0,
                X.get_moments()[0],
            )

            self.assertAllClose(
                x1,
                X.get_moments()[1],
            )

            return
示例#28
0
    def test_message_to_parent(self):
        """
        Test the message to parents of Mixture node.
        """

        K = 3

        # Broadcasting the moments on the cluster axis
        Mu = GaussianARD(2, 1,
                         ndim=0,
                         plates=(K,))
        (mu, mumu) = Mu._message_to_child()
        Alpha = Gamma(3, 1,
                      plates=(K,))
        (alpha, logalpha) = Alpha._message_to_child()
        z = Categorical(np.ones(K)/K)
        X = Mixture(z, GaussianARD, Mu, Alpha)
        tau = 4
        Y = GaussianARD(X, tau)
        y = 5
        Y.observe(y)
        (x, xx) = X._message_to_child()
        m = X._message_to_parent(0)
        self.assertAllClose(m[0],
                            random.gaussian_logpdf(xx*alpha,
                                                   x*alpha*mu,
                                                   mumu*alpha,
                                                   logalpha,
                                                   0))
                                                   
        m = X._message_to_parent(1)
        self.assertAllClose(m[0],
                            1/K * (alpha*x) * np.ones(3))
        self.assertAllClose(m[1],
                            -0.5 * 1/K * alpha * np.ones(3))

        # Some parameters do not have cluster plate axis
        Mu = GaussianARD(2, 1,
                         ndim=0,
                         plates=(K,))
        (mu, mumu) = Mu._message_to_child()
        Alpha = Gamma(3, 1) # Note: no cluster plate axis!
        (alpha, logalpha) = Alpha._message_to_child()
        z = Categorical(np.ones(K)/K)
        X = Mixture(z, GaussianARD, Mu, Alpha)
        tau = 4
        Y = GaussianARD(X, tau)
        y = 5
        Y.observe(y)
        (x, xx) = X._message_to_child()
        m = X._message_to_parent(0)
        self.assertAllClose(m[0],
                            random.gaussian_logpdf(xx*alpha,
                                                   x*alpha*mu,
                                                   mumu*alpha,
                                                   logalpha,
                                                   0))
                                                   
        m = X._message_to_parent(1)
        self.assertAllClose(m[0],
                            1/K * (alpha*x) * np.ones(3))
        self.assertAllClose(m[1],
                            -0.5 * 1/K * alpha * np.ones(3))

        # Cluster assignments do not have as many plate axes as parameters.
        M = 2
        Mu = GaussianARD(2, 1,
                         ndim=0,
                         plates=(K,M))
        (mu, mumu) = Mu._message_to_child()
        Alpha = Gamma(3, 1,
                      plates=(K,M))
        (alpha, logalpha) = Alpha._message_to_child()
        z = Categorical(np.ones(K)/K)
        X = Mixture(z, GaussianARD, Mu, Alpha, cluster_plate=-2)
        tau = 4
        Y = GaussianARD(X, tau)
        y = 5 * np.ones(M)
        Y.observe(y)
        (x, xx) = X._message_to_child()
        m = X._message_to_parent(0)
        self.assertAllClose(m[0]*np.ones(K),
                            np.sum(random.gaussian_logpdf(xx*alpha,
                                                          x*alpha*mu,
                                                          mumu*alpha,
                                                          logalpha,
                                                          0) *
                                   np.ones((K,M)),
                                   axis=-1))
                                                   
        m = X._message_to_parent(1)
        self.assertAllClose(m[0] * np.ones((K,M)),
                            1/K * (alpha*x) * np.ones((K,M)))
        self.assertAllClose(m[1] * np.ones((K,M)),
                            -0.5 * 1/K * alpha * np.ones((K,M)))
        

        pass
示例#29
0
    def test_gradient(self):
        """Test standard gradient of a Gamma node."""
        D = 3

        np.random.seed(42)

        #
        # Without observations
        #

        # Construct model
        a = np.random.rand(D)
        b = np.random.rand(D)
        tau = Gamma(a, b)
        Q = VB(tau)
        # Random initialization
        tau.initialize_from_parameters(np.random.rand(D),
                                       np.random.rand(D))
        # Initial parameters
        phi0 = tau.phi
        # Gradient
        rg = tau.get_riemannian_gradient()
        g = tau.get_gradient(rg)
        # Numerical gradient
        eps = 1e-8
        p0 = tau.get_parameters()
        l0 = Q.compute_lowerbound(ignore_masked=False)
        g_num = [np.zeros(D), np.zeros(D)]
        for i in range(D):
            e = np.zeros(D)
            e[i] = eps
            p1 = p0[0] + e
            tau.set_parameters([p1, p0[1]])
            l1 = Q.compute_lowerbound(ignore_masked=False)
            g_num[0][i] = (l1 - l0) / eps
        for i in range(D):
            e = np.zeros(D)
            e[i] = eps
            p1 = p0[1] + e
            tau.set_parameters([p0[0], p1])
            l1 = Q.compute_lowerbound(ignore_masked=False)
            g_num[1][i] = (l1 - l0) / eps

        # Check
        self.assertAllClose(g[0],
                            g_num[0])
        self.assertAllClose(g[1],
                            g_num[1])

        #
        # With observations
        #

        # Construct model
        a = np.random.rand(D)
        b = np.random.rand(D)
        tau = Gamma(a, b)
        mu = np.random.randn(D)
        Y = GaussianARD(mu, tau)
        Y.observe(np.random.randn(D))
        Q = VB(Y, tau)
        # Random initialization
        tau.initialize_from_parameters(np.random.rand(D),
                                       np.random.rand(D))
        # Initial parameters
        phi0 = tau.phi
        # Gradient
        rg = tau.get_riemannian_gradient()
        g = tau.get_gradient(rg)
        # Numerical gradient
        eps = 1e-8
        p0 = tau.get_parameters()
        l0 = Q.compute_lowerbound(ignore_masked=False)
        g_num = [np.zeros(D), np.zeros(D)]
        for i in range(D):
            e = np.zeros(D)
            e[i] = eps
            p1 = p0[0] + e
            tau.set_parameters([p1, p0[1]])
            l1 = Q.compute_lowerbound(ignore_masked=False)
            g_num[0][i] = (l1 - l0) / eps
        for i in range(D):
            e = np.zeros(D)
            e[i] = eps
            p1 = p0[1] + e
            tau.set_parameters([p0[0], p1])
            l1 = Q.compute_lowerbound(ignore_masked=False)
            g_num[1][i] = (l1 - l0) / eps

        # Check
        self.assertAllClose(g[0],
                            g_num[0])
        self.assertAllClose(g[1],
                            g_num[1])

        pass
示例#30
0
# 
# where $\mathcal{N}$ is the Gaussian distribution parameterized by its mean and precision (i.e., inverse variance), and $\mathcal{G}$ is the gamma distribution parameterized by its shape and rate parameters. Note that we have given quite uninformative priors for the variables $\mu$ and $\tau$.  This simple model can also be shown as a directed factor graph:

# This model can be constructed in BayesPy as follows:

# In[2]:

from bayespy.nodes import GaussianARD, Gamma
mu = GaussianARD(0, 1e-6)
tau = Gamma(1e-6, 1e-6)
y = GaussianARD(mu, tau, plates=(10,))


# In[3]:

y.observe(data)


# Next we want to estimate the posterior distribution.  In principle, we could use different inference engines (e.g., MCMC or EP) but currently only variational Bayesian (VB) engine is implemented.  The engine is initialized by giving all the nodes of the model:

# In[4]:

from bayespy.inference import VB
Q = VB(mu, tau, y)


# The inference algorithm can be run as long as wanted (max. 20 iterations in this case):

# In[5]:

Q.update(repeat=20)
示例#31
0
from bayespy.inference import VB
Q = VB(X, C, gamma, A, alpha, tau, Y)
w = 0.3
a = np.array([[np.cos(w), -np.sin(w), 0, 0], [np.sin(w),
                                              np.cos(w), 0, 0], [0, 0, 1, 0],
              [0, 0, 0, 0]])
c = np.random.randn(M, 4)
x = np.empty((N, 4))
f = np.empty((M, N))
y = np.empty((M, N))
x[0] = 10 * np.random.randn(4)
f[:, 0] = np.dot(c, x[0])
y[:, 0] = f[:, 0] + 3 * np.random.randn(M)
for n in range(N - 1):
    x[n + 1] = np.dot(a, x[n]) + [1, 1, 10, 10] * np.random.randn(4)
    f[:, n + 1] = np.dot(c, x[n + 1])
    y[:, n + 1] = f[:, n + 1] + 3 * np.random.randn(M)
from bayespy.utils import random
mask = random.mask(M, N, p=0.2)
Y.observe(y, mask=mask)
import bayespy.plot as bpplt
Q.update(repeat=10)
from bayespy.inference.vmp import transformations
rotC = transformations.RotateGaussianARD(C, gamma)
rotA = transformations.RotateGaussianARD(A, alpha)
rotX = transformations.RotateGaussianMarkovChain(X, rotA)
R = transformations.RotationOptimizer(rotX, rotC, D)
Q.callback = R.rotate
Q.update(repeat=1000)
bpplt.plot(F, center=True)
bpplt.pyplot.show()
示例#32
0
    def test_message_to_child(self):
        """
        Test moments of GaussianARD.
        """

        # Check that moments have full shape when broadcasting
        X = GaussianARD(np.zeros((2, )), np.ones((3, 2)), shape=(4, 3, 2))
        (u0, u1) = X._message_to_child()
        self.assertEqual(np.shape(u0), (4, 3, 2))
        self.assertEqual(np.shape(u1), (4, 3, 2, 4, 3, 2))

        # Check the formula
        X = GaussianARD(2, 3)
        (u0, u1) = X._message_to_child()
        self.assertAllClose(u0, 2)
        self.assertAllClose(u1, 2**2 + 1 / 3)

        # Check the formula for multidimensional arrays
        X = GaussianARD(2 * np.ones((2, 1, 4)), 3 * np.ones((2, 3, 1)), ndim=3)
        (u0, u1) = X._message_to_child()
        self.assertAllClose(u0, 2 * np.ones((2, 3, 4)))
        self.assertAllClose(
            u1, 2**2 * np.ones(
                (2, 3, 4, 2, 3, 4)) + 1 / 3 * misc.identity(2, 3, 4))

        # Check the formula for dim-broadcasted mu
        X = GaussianARD(2 * np.ones((3, 1)), 3 * np.ones((2, 3, 4)), ndim=3)
        (u0, u1) = X._message_to_child()
        self.assertAllClose(u0, 2 * np.ones((2, 3, 4)))
        self.assertAllClose(
            u1, 2**2 * np.ones(
                (2, 3, 4, 2, 3, 4)) + 1 / 3 * misc.identity(2, 3, 4))

        # Check the formula for dim-broadcasted alpha
        X = GaussianARD(2 * np.ones((2, 3, 4)), 3 * np.ones((3, 1)), ndim=3)
        (u0, u1) = X._message_to_child()
        self.assertAllClose(u0, 2 * np.ones((2, 3, 4)))
        self.assertAllClose(
            u1, 2**2 * np.ones(
                (2, 3, 4, 2, 3, 4)) + 1 / 3 * misc.identity(2, 3, 4))

        # Check the formula for dim-broadcasted mu and alpha
        X = GaussianARD(2 * np.ones((3, 1)),
                        3 * np.ones((3, 1)),
                        shape=(2, 3, 4))
        (u0, u1) = X._message_to_child()
        self.assertAllClose(u0, 2 * np.ones((2, 3, 4)))
        self.assertAllClose(
            u1, 2**2 * np.ones(
                (2, 3, 4, 2, 3, 4)) + 1 / 3 * misc.identity(2, 3, 4))

        # Check the formula for dim-broadcasted mu with plates
        mu = GaussianARD(2 * np.ones((5, 1, 3, 4)),
                         np.ones((5, 1, 3, 4)),
                         shape=(3, 4),
                         plates=(5, 1))
        X = GaussianARD(mu,
                        3 * np.ones((5, 2, 3, 4)),
                        shape=(2, 3, 4),
                        plates=(5, ))
        (u0, u1) = X._message_to_child()
        self.assertAllClose(u0, 2 * np.ones((5, 2, 3, 4)))
        self.assertAllClose(
            u1, 2**2 * np.ones(
                (5, 2, 3, 4, 2, 3, 4)) + 1 / 3 * misc.identity(2, 3, 4))

        # Check posterior
        X = GaussianARD(2, 3)
        Y = GaussianARD(X, 1)
        Y.observe(10)
        X.update()
        (u0, u1) = X._message_to_child()
        self.assertAllClose(u0, 1 / (3 + 1) * (3 * 2 + 1 * 10))
        self.assertAllClose(u1,
                            (1 / (3 + 1) * (3 * 2 + 1 * 10))**2 + 1 / (3 + 1))

        pass
示例#33
0
    def test_message_to_parent(self):
        """
        Test the message to parents of Concatenate node.
        """

        # Two parents without shapes
        X1 = GaussianARD(0, 1, plates=(2, ), shape=())
        X2 = GaussianARD(0, 1, plates=(3, ), shape=())
        Z = Concatenate(X1, X2)
        Y = GaussianARD(Z, 1)
        Y.observe(np.random.randn(*Y.get_shape(0)))
        m1 = X1._message_from_children()
        m2 = X2._message_from_children()
        m = Z._message_from_children()
        self.assertAllClose((m[0] * np.ones((5, )))[:2], m1[0] * np.ones(
            (2, )))
        self.assertAllClose((m[1] * np.ones((5, )))[:2], m1[1] * np.ones(
            (2, )))
        self.assertAllClose((m[0] * np.ones((5, )))[2:], m2[0] * np.ones(
            (3, )))
        self.assertAllClose((m[1] * np.ones((5, )))[2:], m2[1] * np.ones(
            (3, )))

        # Two parents with shapes
        with warnings.catch_warnings():
            warnings.simplefilter("ignore", FutureWarning)

            X1 = GaussianARD(0, 1, plates=(2, ), shape=(4, 6))
            X2 = GaussianARD(0, 1, plates=(3, ), shape=(4, 6))
            Z = Concatenate(X1, X2)
            Y = GaussianARD(Z, 1)
            Y.observe(np.random.randn(*Y.get_shape(0)))
            m1 = X1._message_from_children()
            m2 = X2._message_from_children()
            m = Z._message_from_children()
            self.assertAllClose((m[0] * np.ones((5, 4, 6)))[:2],
                                m1[0] * np.ones((2, 4, 6)))
            self.assertAllClose((m[1] * np.ones((5, 4, 6, 4, 6)))[:2],
                                m1[1] * np.ones((2, 4, 6, 4, 6)))
            self.assertAllClose((m[0] * np.ones((5, 4, 6)))[2:],
                                m2[0] * np.ones((3, 4, 6)))
            self.assertAllClose((m[1] * np.ones((5, 4, 6, 4, 6)))[2:],
                                m2[1] * np.ones((3, 4, 6, 4, 6)))

            # Two parents with non-default concatenation axis
            X1 = GaussianARD(0, 1, plates=(2, 4), shape=())
            X2 = GaussianARD(0, 1, plates=(3, 4), shape=())
            Z = Concatenate(X1, X2, axis=-2)
            Y = GaussianARD(Z, 1)
            Y.observe(np.random.randn(*Y.get_shape(0)))
            m1 = X1._message_from_children()
            m2 = X2._message_from_children()
            m = Z._message_from_children()
            self.assertAllClose((m[0] * np.ones((5, 4)))[:2], m1[0] * np.ones(
                (2, 4)))
            self.assertAllClose((m[1] * np.ones((5, 4)))[:2], m1[1] * np.ones(
                (2, 4)))
            self.assertAllClose((m[0] * np.ones((5, 4)))[2:], m2[0] * np.ones(
                (3, 4)))
            self.assertAllClose((m[1] * np.ones((5, 4)))[2:], m2[1] * np.ones(
                (3, 4)))

            # Constant parent
            X1 = np.random.randn(2, 4, 6)
            X2 = GaussianARD(0, 1, plates=(3, ), shape=(4, 6))
            Z = Concatenate(X1, X2)
            Y = GaussianARD(Z, 1)
            Y.observe(np.random.randn(*Y.get_shape(0)))
            m1 = Z._message_to_parent(0)
            m2 = X2._message_from_children()
            m = Z._message_from_children()
            self.assertAllClose((m[0] * np.ones((5, 4, 6)))[:2],
                                m1[0] * np.ones((2, 4, 6)))
            self.assertAllClose((m[1] * np.ones((5, 4, 6, 4, 6)))[:2],
                                m1[1] * np.ones((2, 4, 6, 4, 6)))
            self.assertAllClose((m[0] * np.ones((5, 4, 6)))[2:],
                                m2[0] * np.ones((3, 4, 6)))
            self.assertAllClose((m[1] * np.ones((5, 4, 6, 4, 6)))[2:],
                                m2[1] * np.ones((3, 4, 6, 4, 6)))

        pass
示例#34
0
    def test_message_to_parent(self):
        """
        Test the message to parents of Gate node.
        """

        # Unobserved and broadcasting
        Z = 2
        X = GaussianARD(0, 1, shape=(), plates=(3, ))
        F = Gate(Z, X)
        Y = GaussianARD(F, 1)
        m = F._message_to_parent(0)
        self.assertEqual(len(m), 1)
        self.assertAllClose(m[0], 0 * np.ones(3))
        m = F._message_to_parent(1)
        self.assertEqual(len(m), 2)
        self.assertAllClose(m[0] * np.ones(3), [0, 0, 0])
        self.assertAllClose(m[1] * np.ones(3), [0, 0, 0])

        # Gating scalar node
        Z = 2
        X = GaussianARD([1, 2, 3], 1, shape=(), plates=(3, ))
        F = Gate(Z, X)
        Y = GaussianARD(F, 1)
        Y.observe(10)
        m = F._message_to_parent(0)
        self.assertAllClose(
            m[0], [10 * 1 - 0.5 * 2, 10 * 2 - 0.5 * 5, 10 * 3 - 0.5 * 10])
        m = F._message_to_parent(1)
        self.assertAllClose(m[0], [0, 0, 10])
        self.assertAllClose(m[1], [0, 0, -0.5])

        # Fixed X
        Z = 2
        X = [1, 2, 3]
        F = Gate(Z, X, moments=GaussianMoments(0))
        Y = GaussianARD(F, 1)
        Y.observe(10)
        m = F._message_to_parent(0)
        self.assertAllClose(
            m[0], [10 * 1 - 0.5 * 1, 10 * 2 - 0.5 * 4, 10 * 3 - 0.5 * 9])
        m = F._message_to_parent(1)
        self.assertAllClose(m[0], [0, 0, 10])
        self.assertAllClose(m[1], [0, 0, -0.5])

        # Uncertain gating
        Z = Categorical([0.2, 0.3, 0.5])
        X = GaussianARD([1, 2, 3], 1, shape=(), plates=(3, ))
        F = Gate(Z, X)
        Y = GaussianARD(F, 1)
        Y.observe(10)
        m = F._message_to_parent(0)
        self.assertAllClose(
            m[0], [10 * 1 - 0.5 * 2, 10 * 2 - 0.5 * 5, 10 * 3 - 0.5 * 10])
        m = F._message_to_parent(1)
        self.assertAllClose(m[0], [0.2 * 10, 0.3 * 10, 0.5 * 10])
        self.assertAllClose(m[1], [-0.5 * 0.2, -0.5 * 0.3, -0.5 * 0.5])

        # Plates in Z
        Z = [2, 0]
        X = GaussianARD([1, 2, 3], 1, shape=(), plates=(3, ))
        F = Gate(Z, X)
        Y = GaussianARD(F, 1)
        Y.observe([10, 20])
        m = F._message_to_parent(0)
        self.assertAllClose(
            m[0], [[10 * 1 - 0.5 * 2, 10 * 2 - 0.5 * 5, 10 * 3 - 0.5 * 10],
                   [20 * 1 - 0.5 * 2, 20 * 2 - 0.5 * 5, 20 * 3 - 0.5 * 10]])
        m = F._message_to_parent(1)
        self.assertAllClose(m[0], [20, 0, 10])
        self.assertAllClose(m[1], [-0.5, 0, -0.5])

        # Plates in X
        Z = 2
        X = GaussianARD([[1, 2, 3], [4, 5, 6]], 1, shape=(), plates=(
            2,
            3,
        ))
        F = Gate(Z, X)
        Y = GaussianARD(F, 1)
        Y.observe([10, 20])
        m = F._message_to_parent(0)
        self.assertAllClose(m[0], [
            10 * 1 - 0.5 * 2 + 20 * 4 - 0.5 * 17, 10 * 2 - 0.5 * 5 + 20 * 5 -
            0.5 * 26, 10 * 3 - 0.5 * 10 + 20 * 6 - 0.5 * 37
        ])
        m = F._message_to_parent(1)
        self.assertAllClose(m[0], [[0, 0, 10], [0, 0, 20]])
        self.assertAllClose(m[1] * np.ones((2, 3)),
                            [[0, 0, -0.5], [0, 0, -0.5]])

        # Gating non-default plate
        Z = 2
        X = GaussianARD([[1], [2], [3]], 1, shape=(), plates=(3, 1))
        F = Gate(Z, X, gated_plate=-2)
        Y = GaussianARD(F, 1)
        Y.observe([10])
        m = F._message_to_parent(0)
        self.assertAllClose(
            m[0], [10 * 1 - 0.5 * 2, 10 * 2 - 0.5 * 5, 10 * 3 - 0.5 * 10])
        m = F._message_to_parent(1)
        self.assertAllClose(m[0], [[0], [0], [10]])
        self.assertAllClose(m[1], [[0], [0], [-0.5]])

        # Gating non-scalar node
        Z = 2
        X = GaussianARD([[1, 4], [2, 5], [3, 6]], 1, shape=(2, ), plates=(3, ))
        F = Gate(Z, X)
        Y = GaussianARD(F, 1)
        Y.observe([10, 20])
        m = F._message_to_parent(0)
        self.assertAllClose(m[0], [
            10 * 1 - 0.5 * 2 + 20 * 4 - 0.5 * 17, 10 * 2 - 0.5 * 5 + 20 * 5 -
            0.5 * 26, 10 * 3 - 0.5 * 10 + 20 * 6 - 0.5 * 37
        ])
        m = F._message_to_parent(1)
        I = np.identity(2)
        self.assertAllClose(m[0], [[0, 0], [0, 0], [10, 20]])
        self.assertAllClose(m[1], [0 * I, 0 * I, -0.5 * I])

        # Broadcasting the moments on the cluster axis
        Z = 2
        X = GaussianARD(2, 1, shape=(), plates=(3, ))
        F = Gate(Z, X)
        Y = GaussianARD(F, 1)
        Y.observe(10)
        m = F._message_to_parent(0)
        self.assertAllClose(
            m[0], [10 * 2 - 0.5 * 5, 10 * 2 - 0.5 * 5, 10 * 2 - 0.5 * 5])
        m = F._message_to_parent(1)
        self.assertAllClose(m[0], [0, 0, 10])
        self.assertAllClose(m[1], [0, 0, -0.5])

        pass