コード例 #1
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def test_vae():
    minibatch_size = 10
    data = pm.floatX(np.random.rand(100))
    x_mini = pm.Minibatch(data, minibatch_size)
    x_inp = at.vector()
    x_inp.tag.test_value = data[:minibatch_size]

    ae = aesara.shared(pm.floatX([0.1, 0.1]))
    be = aesara.shared(pm.floatX(1.0))

    ad = aesara.shared(pm.floatX(1.0))
    bd = aesara.shared(pm.floatX(1.0))

    enc = x_inp.dimshuffle(0, "x") * ae.dimshuffle("x", 0) + be
    mu, rho = enc[:, 0], enc[:, 1]

    with pm.Model():
        # Hidden variables
        zs = pm.Normal("zs", mu=0, sigma=1, size=minibatch_size)
        dec = zs * ad + bd
        # Observation model
        pm.Normal("xs_", mu=dec, sigma=0.1, observed=x_inp)

        pm.fit(
            1,
            local_rv={zs: dict(mu=mu, rho=rho)},
            more_replacements={x_inp: x_mini},
            more_obj_params=[ae, be, ad, bd],
        )
コード例 #2
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def test_discrete_not_allowed():
    mu_true = np.array([-2, 0, 2])
    z_true = np.random.randint(len(mu_true), size=100)
    y = np.random.normal(mu_true[z_true], np.ones_like(z_true))

    with pm.Model():
        mu = pm.Normal("mu", mu=0, sigma=10, size=3)
        z = pm.Categorical("z", p=at.ones(3) / 3, size=len(y))
        pm.Normal("y_obs", mu=mu[z], sigma=1.0, observed=y)
        with pytest.raises(opvi.ParametrizationError):
            pm.fit(n=1)  # fails
コード例 #3
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def test_fit_with_nans(score):
    X_mean = pm.floatX(np.linspace(0, 10, 10))
    y = pm.floatX(np.random.normal(X_mean * 4, 0.05))
    with pm.Model():
        inp = pm.Normal("X", X_mean, size=X_mean.shape)
        coef = pm.Normal("b", 4.0)
        mean = inp * coef
        pm.Normal("y", mean, 0.1, observed=y)
        with pytest.raises(FloatingPointError) as e:
            advi = pm.fit(100, score=score, obj_optimizer=pm.adam(learning_rate=float("nan")))
コード例 #4
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def test_var_replacement():
    X_mean = pm.floatX(np.linspace(0, 10, 10))
    y = pm.floatX(np.random.normal(X_mean * 4, 0.05))
    with pm.Model():
        inp = pm.Normal("X", X_mean, size=X_mean.shape)
        coef = pm.Normal("b", 4.0)
        mean = inp * coef
        pm.Normal("y", mean, 0.1, observed=y)
        advi = pm.fit(100)
        assert advi.sample_node(mean).eval().shape == (10,)
        x_new = pm.floatX(np.linspace(0, 10, 11))
        assert advi.sample_node(mean, more_replacements={inp: x_new}).eval().shape == (11,)