Пример #1
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def test_check_needless():
    complete_prior = {
        "lengthscale": tfd.Gamma(1.0, 1.0),
        "variance": tfd.Gamma(2.0, 2.0),
        "obs_noise": tfd.Gamma(3.0, 3.0),
        "latent": tfd.Normal(loc=0.0, scale=1.0),
    }
    posterior = Prior(kernel=RBF()) * Bernoulli()
    priors = prior_checks(posterior, complete_prior)
    assert priors == complete_prior
Пример #2
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def prior_checks(gp: NonConjugatePosterior, priors: dict) -> dict:
    if "latent" in priors.keys():
        latent_prior = priors["latent"]
        if latent_prior.name != "Normal":
            warnings.warn(
                f"A {latent_prior.name} distribution prior has been placed on the latent function. It is strongly afvised that a unit-Gaussian prior is used."
            )
        return priors
    else:
        priors["latent"] = tfd.Normal(loc=0.0, scale=1.0)
        return priors
Пример #3
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def test_transformed_distributions():
    from tensorflow_probability.substrates.jax import (
        bijectors as tfb,
        distributions as tfd,
    )

    d = dist.TransformedDistribution(dist.Normal(0, 1), dist.transforms.ExpTransform())
    d1 = tfd.TransformedDistribution(tfd.Normal(0, 1), tfb.Exp())
    x = random.normal(random.PRNGKey(0), (1000,))
    d_x = d.log_prob(x).sum()
    d1_x = d1.log_prob(x).sum()
    assert_allclose(d_x, d1_x)
Пример #4
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def test_sample_unwrapped_mixture_same_family():
    from tensorflow_probability.substrates.jax import distributions as tfd

    # test no error is raised
    with numpyro.handlers.seed(rng_seed=random.PRNGKey(0)):
        numpyro.sample(
            "sample",
            tfd.MixtureSameFamily(
                mixture_distribution=tfd.Categorical(probs=[0.3, 0.7]),
                components_distribution=tfd.Normal(
                    loc=[-1.0, 1], scale=[0.1, 0.5]  # One for each component.
                ),
            ),
        )
Пример #5
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    def mll(
        params: dict, x: Array, y: Array, priors: dict = {"latent": tfd.Normal(loc=0.0, scale=1.0)}
    ):
        params = transform(params)
        n = x.shape[0]
        link = link_function(gp.likelihood)
        gram_matrix = gram(gp.prior.kernel, x, params)
        gram_matrix += I(n) * jitter
        L = jnp.linalg.cholesky(gram_matrix)
        F = jnp.matmul(L, params["latent"])
        rv = link(F)
        ll = jnp.sum(rv.log_prob(y))

        priors = prior_checks(gp, priors)
        log_prior_density = evaluate_prior(params, priors)
        constant = jnp.array(-1.0) if negative else jnp.array(1.0)
        return constant * (ll + log_prior_density)
Пример #6
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    def mll(
        params: dict,
        training: Dataset,
        priors: dict = {"latent": tfd.Normal(loc=0.0, scale=1.0)},
        static_params: dict = None,
    ):
        x, y = training.X, training.y
        n = training.n
        params = transform(params)
        if static_params:
            params = concat_dictionaries(params, transform(static_params))
        link = link_function(gp.likelihood)
        gram_matrix = gram(gp.prior.kernel, x, params)
        gram_matrix += I(n) * jitter
        L = jnp.linalg.cholesky(gram_matrix)
        F = jnp.matmul(L, params["latent"])
        rv = link(F)
        ll = jnp.sum(rv.log_prob(y))

        priors = prior_checks(gp, priors)
        log_prior_density = evaluate_prior(params, priors)
        constant = jnp.array(-1.0) if negative else jnp.array(1.0)
        return constant * (ll + log_prior_density)
Пример #7
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def test_lpd(x):
    val = jnp.array(x)
    dist = tfd.Normal(loc=0.0, scale=1.0)
    lpd = log_density(val, dist)
    assert lpd is not None
Пример #8
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 def model(labels):
     coefs = numpyro.sample("coefs",
                            tfd.Normal(jnp.zeros(dim), jnp.ones(dim)))
     logits = numpyro.deterministic("logits", jnp.sum(coefs * data,
                                                      axis=-1))
     return numpyro.sample("obs", tfd.Bernoulli(logits=logits), obs=labels)
Пример #9
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 def f(x):
     with numpyro.handlers.seed(rng_seed=0), numpyro.handlers.trace() as tr:
         numpyro.sample("x", tfd.Normal(x, 1))
     return tr["x"]["fn"]
Пример #10
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def spectral_density(kernel: SpectralRBF) -> tfd.Distribution:
    return tfd.Normal(loc=jnp.array(0.0), scale=jnp.array(1.0))