Пример #1
0
    def test_dimensions(self):
        a1 = Normal.dist(mu=0, sigma=1)
        a2 = Normal.dist(mu=10, sigma=1)
        mix = Mixture.dist(w=np.r_[0.5, 0.5], comp_dists=[a1, a2])

        assert mix.mode.ndim == 0
        assert mix.logp(0.0).ndim == 0

        value = np.r_[0.0, 1.0, 2.0]
        assert mix.logp(value).ndim == 1
Пример #2
0
    def test_mixture_of_mixture(self):
        if theano.config.floatX == 'float32':
            rtol = 1e-4
        else:
            rtol = 1e-7
        nbr = 4
        with Model() as model:
            # mixtures components
            g_comp = Normal.dist(
                mu=Exponential('mu_g', lam=1.0, shape=nbr, transform=None),
                sigma=1,
                shape=nbr)
            l_comp = Lognormal.dist(
                mu=Exponential('mu_l', lam=1.0, shape=nbr, transform=None),
                sigma=1,
                shape=nbr)
            # weight vector for the mixtures
            g_w = Dirichlet('g_w', a=floatX(np.ones(nbr)*0.0000001), transform=None)
            l_w = Dirichlet('l_w', a=floatX(np.ones(nbr)*0.0000001), transform=None)
            # mixture components
            g_mix = Mixture.dist(w=g_w, comp_dists=g_comp)
            l_mix = Mixture.dist(w=l_w, comp_dists=l_comp)
            # mixture of mixtures
            mix_w = Dirichlet('mix_w', a=floatX(np.ones(2)), transform=None)
            mix = Mixture('mix', w=mix_w,
                          comp_dists=[g_mix, l_mix],
                          observed=np.exp(self.norm_x))

        test_point = model.test_point

        def mixmixlogp(value, point):
            floatX = theano.config.floatX
            priorlogp = st.dirichlet.logpdf(x=point['g_w'],
                                            alpha=np.ones(nbr)*0.0000001,
                                            ).astype(floatX) + \
                        st.expon.logpdf(x=point['mu_g']).sum(dtype=floatX) + \
                        st.dirichlet.logpdf(x=point['l_w'],
                                            alpha=np.ones(nbr)*0.0000001,
                                            ).astype(floatX) + \
                        st.expon.logpdf(x=point['mu_l']).sum(dtype=floatX) + \
                        st.dirichlet.logpdf(x=point['mix_w'],
                                            alpha=np.ones(2),
                                            ).astype(floatX)
            complogp1 = st.norm.logpdf(x=value,
                                       loc=point['mu_g']).astype(floatX)
            mixlogp1 = logsumexp(np.log(point['g_w']).astype(floatX) +
                                 complogp1,
                                 axis=-1, keepdims=True)
            complogp2 = st.lognorm.logpdf(value,
                                          1.,
                                          0.,
                                          np.exp(point['mu_l'])).astype(floatX)
            mixlogp2 = logsumexp(np.log(point['l_w']).astype(floatX) +
                                 complogp2,
                                 axis=-1, keepdims=True)
            complogp_mix = np.concatenate((mixlogp1, mixlogp2), axis=1)
            mixmixlogpg = logsumexp(np.log(point['mix_w']).astype(floatX) +
                                    complogp_mix,
                                    axis=-1, keepdims=True)
            return priorlogp, mixmixlogpg

        value = np.exp(self.norm_x)[:, None]
        priorlogp, mixmixlogpg = mixmixlogp(value, test_point)

        # check logp of mixture
        assert_allclose(mixmixlogpg, mix.logp_elemwise(test_point),
                        rtol=rtol)

        # check model logp
        assert_allclose(priorlogp + mixmixlogpg.sum(),
                        model.logp(test_point),
                        rtol=rtol)

        # check input and check logp again
        test_point['g_w'] = np.asarray([.1, .1, .2, .6])
        test_point['mu_g'] = np.exp(np.random.randn(nbr))
        priorlogp, mixmixlogpg = mixmixlogp(value, test_point)
        assert_allclose(mixmixlogpg, mix.logp_elemwise(test_point),
                        rtol=rtol)
        assert_allclose(priorlogp + mixmixlogpg.sum(),
                        model.logp(test_point),
                        rtol=rtol)
Пример #3
0
    def test_mixture_of_mixture(self):
        if theano.config.floatX == "float32":
            rtol = 1e-4
        else:
            rtol = 1e-7
        nbr = 4
        with Model() as model:
            # mixtures components
            g_comp = Normal.dist(mu=Exponential("mu_g",
                                                lam=1.0,
                                                shape=nbr,
                                                transform=None),
                                 sigma=1,
                                 shape=nbr)
            l_comp = Lognormal.dist(mu=Exponential("mu_l",
                                                   lam=1.0,
                                                   shape=nbr,
                                                   transform=None),
                                    sigma=1,
                                    shape=nbr)
            # weight vector for the mixtures
            g_w = Dirichlet("g_w",
                            a=floatX(np.ones(nbr) * 0.0000001),
                            transform=None,
                            shape=(nbr, ))
            l_w = Dirichlet("l_w",
                            a=floatX(np.ones(nbr) * 0.0000001),
                            transform=None,
                            shape=(nbr, ))
            # mixture components
            g_mix = Mixture.dist(w=g_w, comp_dists=g_comp)
            l_mix = Mixture.dist(w=l_w, comp_dists=l_comp)
            # mixture of mixtures
            mix_w = Dirichlet("mix_w",
                              a=floatX(np.ones(2)),
                              transform=None,
                              shape=(2, ))
            mix = Mixture("mix",
                          w=mix_w,
                          comp_dists=[g_mix, l_mix],
                          observed=np.exp(self.norm_x))

        test_point = model.test_point

        def mixmixlogp(value, point):
            floatX = theano.config.floatX
            priorlogp = (st.dirichlet.logpdf(
                x=point["g_w"],
                alpha=np.ones(nbr) * 0.0000001,
            ).astype(floatX) +
                         st.expon.logpdf(x=point["mu_g"]).sum(dtype=floatX) +
                         st.dirichlet.logpdf(
                             x=point["l_w"],
                             alpha=np.ones(nbr) * 0.0000001,
                         ).astype(floatX) +
                         st.expon.logpdf(x=point["mu_l"]).sum(dtype=floatX) +
                         st.dirichlet.logpdf(
                             x=point["mix_w"],
                             alpha=np.ones(2),
                         ).astype(floatX))
            complogp1 = st.norm.logpdf(x=value,
                                       loc=point["mu_g"]).astype(floatX)
            mixlogp1 = logsumexp(np.log(point["g_w"]).astype(floatX) +
                                 complogp1,
                                 axis=-1,
                                 keepdims=True)
            complogp2 = st.lognorm.logpdf(value, 1.0, 0.0,
                                          np.exp(point["mu_l"])).astype(floatX)
            mixlogp2 = logsumexp(np.log(point["l_w"]).astype(floatX) +
                                 complogp2,
                                 axis=-1,
                                 keepdims=True)
            complogp_mix = np.concatenate((mixlogp1, mixlogp2), axis=1)
            mixmixlogpg = logsumexp(np.log(point["mix_w"]).astype(floatX) +
                                    complogp_mix,
                                    axis=-1,
                                    keepdims=False)
            return priorlogp, mixmixlogpg

        value = np.exp(self.norm_x)[:, None]
        priorlogp, mixmixlogpg = mixmixlogp(value, test_point)

        # check logp of mixture
        assert_allclose(mixmixlogpg, mix.logp_elemwise(test_point), rtol=rtol)

        # check model logp
        assert_allclose(priorlogp + mixmixlogpg.sum(),
                        model.logp(test_point),
                        rtol=rtol)

        # check input and check logp again
        test_point["g_w"] = np.asarray([0.1, 0.1, 0.2, 0.6])
        test_point["mu_g"] = np.exp(np.random.randn(nbr))
        priorlogp, mixmixlogpg = mixmixlogp(value, test_point)
        assert_allclose(mixmixlogpg, mix.logp_elemwise(test_point), rtol=rtol)
        assert_allclose(priorlogp + mixmixlogpg.sum(),
                        model.logp(test_point),
                        rtol=rtol)
Пример #4
0
    def test_mixture_of_mixture(self):
        nbr = 4
        with Model() as model:
            # mixtures components
            g_comp = Normal.dist(mu=Exponential('mu_g',
                                                lam=1.0,
                                                shape=nbr,
                                                transform=None),
                                 sigma=1,
                                 shape=nbr)
            l_comp = Lognormal.dist(mu=Exponential('mu_l',
                                                   lam=1.0,
                                                   shape=nbr,
                                                   transform=None),
                                    sigma=1,
                                    shape=nbr)
            # weight vector for the mixtures
            g_w = Dirichlet('g_w',
                            a=floatX(np.ones(nbr) * 0.0000001),
                            transform=None)
            l_w = Dirichlet('l_w',
                            a=floatX(np.ones(nbr) * 0.0000001),
                            transform=None)
            # mixture components
            g_mix = Mixture.dist(w=g_w, comp_dists=g_comp)
            l_mix = Mixture.dist(w=l_w, comp_dists=l_comp)
            # mixture of mixtures
            mix_w = Dirichlet('mix_w', a=floatX(np.ones(2)), transform=None)
            mix = Mixture('mix',
                          w=mix_w,
                          comp_dists=[g_mix, l_mix],
                          observed=np.exp(self.norm_x))

        test_point = model.test_point

        def mixmixlogp(value, point):
            priorlogp = st.dirichlet.logpdf(x=point['g_w'],
                                            alpha=np.ones(nbr)*0.0000001,
                                            ) + \
                        st.expon.logpdf(x=point['mu_g']).sum() + \
                        st.dirichlet.logpdf(x=point['l_w'],
                                            alpha=np.ones(nbr)*0.0000001,
                                            ) + \
                        st.expon.logpdf(x=point['mu_l']).sum() + \
                        st.dirichlet.logpdf(x=point['mix_w'],
                                            alpha=np.ones(2),
                                            )
            complogp1 = st.norm.logpdf(x=value, loc=point['mu_g'])
            mixlogp1 = logsumexp(np.log(point['g_w']) + complogp1,
                                 axis=-1,
                                 keepdims=True)
            complogp2 = st.lognorm.logpdf(value, 1., 0., np.exp(point['mu_l']))
            mixlogp2 = logsumexp(np.log(point['l_w']) + complogp2,
                                 axis=-1,
                                 keepdims=True)
            complogp_mix = np.concatenate((mixlogp1, mixlogp2), axis=1)
            mixmixlogpg = logsumexp(np.log(point['mix_w']) + complogp_mix,
                                    axis=-1,
                                    keepdims=True)
            return priorlogp, mixmixlogpg

        value = np.exp(self.norm_x)[:, None]
        priorlogp, mixmixlogpg = mixmixlogp(value, test_point)

        # check logp of mixture
        assert_allclose(mixmixlogpg, mix.logp_elemwise(test_point))

        # check model logp
        assert_allclose(priorlogp + mixmixlogpg.sum(), model.logp(test_point))

        # check input and check logp again
        test_point['g_w'] = np.asarray([.1, .1, .2, .6])
        test_point['mu_g'] = np.exp(np.random.randn(nbr))
        priorlogp, mixmixlogpg = mixmixlogp(value, test_point)
        assert_allclose(mixmixlogpg, mix.logp_elemwise(test_point))
        assert_allclose(priorlogp + mixmixlogpg.sum(), model.logp(test_point))