Ejemplo n.º 1
0
    def setUp(self):
        self.task = SinFunction()

        kernel = george.kernels.Matern52Kernel(np.ones([self.task.n_dims]) *
                                               0.01,
                                               ndim=self.task.n_dims)

        noise_kernel = george.kernels.WhiteKernel(1e-9, ndim=self.task.n_dims)
        kernel = 3000 * (kernel + noise_kernel)

        prior = default_priors.TophatPrior(-2, 2)
        model = GaussianProcess(kernel, prior=prior)
        X = init_random_uniform(self.task.X_lower, self.task.X_upper, 3)
        Y = self.task.evaluate(X)

        model.train(X, Y, do_optimize=False)
        self.acquisition_func = InformationGain(model,
                                                X_upper=self.task.X_upper,
                                                X_lower=self.task.X_lower)

        self.acquisition_func.update(model)
Ejemplo n.º 2
0
    def setUp(self):
        self.task = SinFunction()
        
        kernel = george.kernels.Matern52Kernel(np.ones([self.task.n_dims]) * 0.01,
                                                       ndim=self.task.n_dims)

        noise_kernel = george.kernels.WhiteKernel(1e-9, ndim=self.task.n_dims)
        kernel = 3000 * (kernel + noise_kernel)

        prior = default_priors.TophatPrior(-2, 2)
        model = GaussianProcess(kernel, prior=prior)
        X = init_random_uniform(self.task.X_lower,
                                self.task.X_upper,
                                3)
        Y = self.task.evaluate(X)

        model.train(X, Y, do_optimize=False)
        self.acquisition_func = InformationGain(model,
                     X_upper=self.task.X_upper,
                     X_lower=self.task.X_lower)

        self.acquisition_func.update(model)
Ejemplo n.º 3
0
    def __init__(self,
                 objective_func,
                 X_lower,
                 X_upper,
                 maximizer="direct",
                 acquisition="LogEI",
                 par=None,
                 n_func_evals=4000,
                 n_iters=500):
        self.objective_func = objective_func
        self.X_lower = X_lower
        self.X_upper = X_upper

        assert self.X_upper.shape[0] == self.X_lower.shape[0]

        self.task = Task(self.X_lower, self.X_upper, self.objective_func)

        cov_amp = 2

        initial_ls = np.ones([self.task.n_dims])
        exp_kernel = george.kernels.Matern32Kernel(initial_ls,
                                                   ndim=self.task.n_dims)
        kernel = cov_amp * exp_kernel
        #kernel = GPy.kern.Matern52(input_dim=task.n_dims)

        prior = DefaultPrior(len(kernel) + 1)

        n_hypers = 3 * len(kernel)
        if n_hypers % 2 == 1:
            n_hypers += 1

        #self.model = GaussianProcessMCMC(kernel, prior=prior, n_hypers=n_hypers, chain_length=500, burnin_steps=100)
        self.model = GaussianProcess(kernel,
                                     prior=prior,
                                     dim=self.X_lower.shape[0],
                                     noise=1e-3)
        #self.model = GPyModel(kernel)

        #MAP ESTMIATE

        if acquisition == "EI":
            if par is not None:
                self.a = EI(self.model,
                            X_upper=self.task.X_upper,
                            X_lower=self.task.X_lower,
                            par=par)
            else:
                self.a = EI(self.model,
                            X_upper=self.task.X_upper,
                            X_lower=self.task.X_lower)
        elif acquisition == "LogEI":
            if par is not None:
                self.a = LogEI(self.model,
                               X_upper=self.task.X_upper,
                               X_lower=self.task.X_lower,
                               par=par)
            else:
                self.a = LogEI(self.model,
                               X_upper=self.task.X_upper,
                               X_lower=self.task.X_lower)
        elif acquisition == "PI":
            self.a = PI(self.model,
                        X_upper=self.task.X_upper,
                        X_lower=self.task.X_lower)
        elif acquisition == "UCB":
            if par is not None:
                self.a = LCB(self.model,
                             X_upper=self.task.X_upper,
                             X_lower=self.task.X_lower,
                             par=par)
            else:
                self.a = LCB(self.model,
                             X_upper=self.task.X_upper,
                             X_lower=self.task.X_lower)
        elif acquisition == "UCB_GP":
            if par is not None:
                self.a = LCB_GP(self.model,
                                X_upper=self.task.X_upper,
                                X_lower=self.task.X_lower,
                                par=par)
            else:
                self.a = LCB_GP(self.model,
                                X_upper=self.task.X_upper,
                                X_lower=self.task.X_lower)
        elif acquisition == "InformationGain":
            self.a = InformationGain(self.model,
                                     X_upper=self.task.X_upper,
                                     X_lower=self.task.X_lower)
        elif acquisition == "InformationGainMC":
            self.a = InformationGainMC(
                self.model,
                X_upper=self.task.X_upper,
                X_lower=self.task.X_lower,
            )
        else:
            logger.error("ERROR: %s is not a"
                         "valid acquisition function!" % (acquisition))
            return None

        #self.acquisition_func = IntegratedAcquisition(self.model, self.a, self.task.X_lower, self.task.X_upper)
        self.acquisition_func = self.a

        if maximizer == "cmaes":
            self.max_fkt = cmaes.CMAES(self.acquisition_func,
                                       self.task.X_lower, self.task.X_upper)
        elif maximizer == "direct":
            self.max_fkt = direct.Direct(
                self.acquisition_func,
                self.task.X_lower,
                self.task.X_upper,
                n_func_evals=n_func_evals,
                n_iters=n_iters)  #default is n_func_evals=400, n_iters=200
        elif maximizer == "stochastic_local_search":
            self.max_fkt = stochastic_local_search.StochasticLocalSearch(
                self.acquisition_func, self.task.X_lower, self.task.X_upper)
        elif maximizer == "grid_search":
            self.max_fkt = grid_search.GridSearch(self.acquisition_func,
                                                  self.task.X_lower,
                                                  self.task.X_upper)
        else:
            logger.error("ERROR: %s is not a valid function"
                         "to maximize the acquisition function!" %
                         (acquisition))
            return None

        self.bo = BayesianOptimization(acquisition_func=self.acquisition_func,
                                       model=self.model,
                                       maximize_func=self.max_fkt,
                                       task=self.task)
Ejemplo n.º 4
0
def fmin(objective_func,
         X_lower,
         X_upper,
         num_iterations=30,
         maximizer="direct",
         acquisition="LogEI",
         initX=None,
         initY=None):

    assert X_upper.shape[0] == X_lower.shape[0]

    class Task(BaseTask):
        def __init__(self, X_lower, X_upper, objective_fkt):
            super(Task, self).__init__(X_lower, X_upper)
            self.objective_function = objective_fkt

    task = Task(X_lower, X_upper, objective_func)

    cov_amp = 2

    initial_ls = np.ones([task.n_dims])
    exp_kernel = george.kernels.Matern52Kernel(initial_ls, ndim=task.n_dims)
    kernel = cov_amp * exp_kernel

    prior = DefaultPrior(len(kernel) + 1)

    n_hypers = 3 * len(kernel)
    if n_hypers % 2 == 1:
        n_hypers += 1
    model = GaussianProcessMCMC(kernel,
                                prior=prior,
                                n_hypers=n_hypers,
                                chain_length=200,
                                burnin_steps=100)

    if acquisition == "EI":
        a = EI(model, X_upper=task.X_upper, X_lower=task.X_lower)
    elif acquisition == "LogEI":
        a = LogEI(model, X_upper=task.X_upper, X_lower=task.X_lower)
    elif acquisition == "PI":
        a = PI(model, X_upper=task.X_upper, X_lower=task.X_lower)
    elif acquisition == "UCB":
        a = LCB(model, X_upper=task.X_upper, X_lower=task.X_lower)
    elif acquisition == "InformationGain":
        a = InformationGain(model, X_upper=task.X_upper, X_lower=task.X_lower)
    elif acquisition == "InformationGainMC":
        a = InformationGainMC(
            model,
            X_upper=task.X_upper,
            X_lower=task.X_lower,
        )
    else:
        logger.error("ERROR: %s is not a"
                     "valid acquisition function!" % (acquisition))
        return None

    acquisition_func = IntegratedAcquisition(model, a, task.X_lower,
                                             task.X_upper)

    if maximizer == "cmaes":
        max_fkt = cmaes.CMAES(acquisition_func, task.X_lower, task.X_upper)
    elif maximizer == "direct":
        max_fkt = direct.Direct(acquisition_func, task.X_lower, task.X_upper)
    elif maximizer == "stochastic_local_search":
        max_fkt = stochastic_local_search.StochasticLocalSearch(
            acquisition_func, task.X_lower, task.X_upper)
    elif maximizer == "grid_search":
        max_fkt = grid_search.GridSearch(acquisition_func, task.X_lower,
                                         task.X_upper)
    else:
        logger.error("ERROR: %s is not a valid function"
                     "to maximize the acquisition function!" % (acquisition))
        return None

    bo = BayesianOptimization(acquisition_func=acquisition_func,
                              model=model,
                              maximize_func=max_fkt,
                              task=task)

    best_x, f_min = bo.run(num_iterations, X=initX, Y=initY)
    return task.retransform(best_x), f_min, model, acquisition_func, max_fkt
Ejemplo n.º 5
0
class InformationGainTestCase(unittest.TestCase):
    def setUp(self):
        self.task = SinFunction()

        kernel = george.kernels.Matern52Kernel(np.ones([self.task.n_dims]) *
                                               0.01,
                                               ndim=self.task.n_dims)

        noise_kernel = george.kernels.WhiteKernel(1e-9, ndim=self.task.n_dims)
        kernel = 3000 * (kernel + noise_kernel)

        prior = default_priors.TophatPrior(-2, 2)
        model = GaussianProcess(kernel, prior=prior)
        X = init_random_uniform(self.task.X_lower, self.task.X_upper, 3)
        Y = self.task.evaluate(X)

        model.train(X, Y, do_optimize=False)
        self.acquisition_func = InformationGain(model,
                                                X_upper=self.task.X_upper,
                                                X_lower=self.task.X_lower)

        self.acquisition_func.update(model)

    def test_sampling_representer_points(self):

        # Check if representer points are inside the bounds
        assert np.any(
            self.acquisition_func.zb >= self.acquisition_func.X_lower)
        assert np.any(
            self.acquisition_func.zb <= self.acquisition_func.X_upper)

    def test_compute_pmin(self):

        # Uniform distribution
        m = np.ones([self.acquisition_func.Nb, 1])
        v = np.eye(self.acquisition_func.Nb)

        pmin = epmgp.joint_min(m, v)
        pmin = np.exp(pmin)

        uprob = 1. / self.acquisition_func.Nb

        assert pmin.shape[0] == self.acquisition_func.Nb
        assert np.any(pmin < (uprob + 0.03)) and np.any(pmin > uprob - 0.01)

        # Dirac delta
        m = np.ones([self.acquisition_func.Nb, 1]) * 1000
        m[0] = 1
        v = np.eye(self.acquisition_func.Nb)

        pmin = epmgp.joint_min(m, v)
        pmin = np.exp(pmin)
        uprob = 1. / self.acquisition_func.Nb
        assert pmin[0] == 1.0
        assert np.any(pmin[:1] > 1e-10)

    def test_innovations(self):
        # Case 1: Assume no influence of test point on representer points
        rep = np.array([[1.0]])
        x = np.array([[0.0]])
        dm, dv = self.acquisition_func.innovations(x, rep)

        assert np.any(np.abs(dm) < 1e-3)
        assert np.any(np.abs(dv) < 1e-3)

        # Case 2: Test point is close to representer points
        rep = np.array([[1.0]])
        x = np.array([[0.99]])
        dm, dv = self.acquisition_func.innovations(x, rep)
        assert np.any(np.abs(dm) > 1e-3)
        assert np.any(np.abs(dv) > 1e-3)

    def test_general_interface(self):

        X_test = init_random_uniform(self.task.X_lower, self.task.X_upper, 1)

        a = self.acquisition_func(X_test, False)

        assert len(a.shape) == 2
        assert a.shape[0] == X_test.shape[0]
        assert a.shape[1] == 1

    def test_check_grads(self):
        x_ = np.array([[0.1]])
        assert check_grad(self.acquisition_func,
                          lambda x: -self.acquisition_func(x, True)[1],
                          x_) < 1e-3
Ejemplo n.º 6
0
    def test(self):
        X_lower = np.array([0])
        X_upper = np.array([1])
        X = init_random_uniform(X_lower, X_upper, 10)
        Y = np.sin(X)

        kernel = george.kernels.Matern52Kernel(np.ones([1]), ndim=1)

        prior = TophatPrior(-2, 2)
        model = GaussianProcess(kernel, prior=prior)
        model.train(X, Y)

        x_test = init_random_uniform(X_lower, X_upper, 3)

        # Shape matching predict
        m, v = model.predict(x_test)

        assert len(m.shape) == 2
        assert m.shape[0] == x_test.shape[0]
        assert m.shape[1] == 1
        assert len(v.shape) == 2
        assert v.shape[0] == x_test.shape[0]
        assert v.shape[1] == x_test.shape[0]

        #TODO: check gradients

        # Shape matching function sampling
        x_ = np.linspace(X_lower, X_upper, 10)
        x_ = x_[:, np.newaxis]
        funcs = model.sample_functions(x_, n_funcs=2)
        assert len(funcs.shape) == 2
        assert funcs.shape[0] == 2
        assert funcs.shape[1] == x_.shape[0]

        # Shape matching predict variance
        x_test1 = np.array([np.random.rand(1)])
        x_test2 = np.random.rand(10)[:, np.newaxis]
        var = model.predict_variance(x_test1, x_test2)
        assert len(var.shape) == 2
        assert var.shape[0] == x_test2.shape[0]
        assert var.shape[1] == 1

        # Check compatibility with all acquisition functions
        acq_func = EI(model, X_upper=X_upper, X_lower=X_lower)
        acq_func.update(model)
        acq_func(x_test)

        acq_func = PI(model, X_upper=X_upper, X_lower=X_lower)
        acq_func.update(model)
        acq_func(x_test)

        acq_func = LCB(model, X_upper=X_upper, X_lower=X_lower)
        acq_func.update(model)
        acq_func(x_test)

        acq_func = InformationGain(model, X_upper=X_upper, X_lower=X_lower)
        acq_func.update(model)
        acq_func(x_test)
        # Check compatibility with all incumbent estimation methods
        rec = BestObservation(model, X_lower, X_upper)
        inc, inc_val = rec.estimate_incumbent(None)
        assert len(inc.shape) == 2
        assert inc.shape[0] == 1
        assert inc.shape[1] == X_upper.shape[0]
        assert len(inc_val.shape) == 2
        assert inc_val.shape[0] == 1
        assert inc_val.shape[1] == 1

        rec = PosteriorMeanOptimization(model, X_lower, X_upper)
        startpoints = init_random_uniform(X_lower, X_upper, 4)
        inc, inc_val = rec.estimate_incumbent(startpoints)
        assert len(inc.shape) == 2
        assert inc.shape[0] == 1
        assert inc.shape[1] == X_upper.shape[0]
        assert len(inc_val.shape) == 2
        assert inc_val.shape[0] == 1
        assert inc_val.shape[1] == 1

        rec = PosteriorMeanAndStdOptimization(model, X_lower, X_upper)
        startpoints = init_random_uniform(X_lower, X_upper, 4)
        inc, inc_val = rec.estimate_incumbent(startpoints)
        assert len(inc.shape) == 2
        assert inc.shape[0] == 1
        assert inc.shape[1] == X_upper.shape[0]
        assert len(inc_val.shape) == 2
        assert inc_val.shape[0] == 1
        assert inc_val.shape[1] == 1
Ejemplo n.º 7
0
class InformationGainTestCase(unittest.TestCase):

    def setUp(self):
        self.task = SinFunction()
        
        kernel = george.kernels.Matern52Kernel(np.ones([self.task.n_dims]) * 0.01,
                                                       ndim=self.task.n_dims)

        noise_kernel = george.kernels.WhiteKernel(1e-9, ndim=self.task.n_dims)
        kernel = 3000 * (kernel + noise_kernel)

        prior = default_priors.TophatPrior(-2, 2)
        model = GaussianProcess(kernel, prior=prior)
        X = init_random_uniform(self.task.X_lower,
                                self.task.X_upper,
                                3)
        Y = self.task.evaluate(X)

        model.train(X, Y, do_optimize=False)
        self.acquisition_func = InformationGain(model,
                     X_upper=self.task.X_upper,
                     X_lower=self.task.X_lower)

        self.acquisition_func.update(model)

    def test_sampling_representer_points(self):

        # Check if representer points are inside the bounds
        assert np.any(self.acquisition_func.zb >= self.acquisition_func.X_lower)
        assert np.any(self.acquisition_func.zb <= self.acquisition_func.X_upper)

    def test_compute_pmin(self):

        # Uniform distribution
        m = np.ones([self.acquisition_func.Nb, 1])
        v = np.eye(self.acquisition_func.Nb)

        pmin = epmgp.joint_min(m, v)
        pmin = np.exp(pmin)

        uprob = 1. / self.acquisition_func.Nb

        assert pmin.shape[0] == self.acquisition_func.Nb
        assert np.any(pmin < (uprob + 0.03)) and np.any(pmin > uprob - 0.01)

        # Dirac delta
        m = np.ones([self.acquisition_func.Nb, 1]) * 1000
        m[0] = 1
        v = np.eye(self.acquisition_func.Nb)

        pmin = epmgp.joint_min(m, v)
        pmin = np.exp(pmin)
        uprob = 1. / self.acquisition_func.Nb
        assert pmin[0] == 1.0
        assert np.any(pmin[:1] > 1e-10)

    def test_innovations(self):
        # Case 1: Assume no influence of test point on representer points
        rep = np.array([[1.0]])
        x = np.array([[0.0]])
        dm, dv = self.acquisition_func.innovations(x, rep)

        assert np.any(np.abs(dm) < 1e-3)
        assert np.any(np.abs(dv) < 1e-3)

        # Case 2: Test point is close to representer points
        rep = np.array([[1.0]])
        x = np.array([[0.99]])
        dm, dv = self.acquisition_func.innovations(x, rep)
        assert np.any(np.abs(dm) > 1e-3)
        assert np.any(np.abs(dv) > 1e-3)

    def test_general_interface(self):

        X_test = init_random_uniform(self.task.X_lower, self.task.X_upper, 1)

        a = self.acquisition_func(X_test, False)

        assert len(a.shape) == 2
        assert a.shape[0] == X_test.shape[0]
        assert a.shape[1] == 1

    def test_check_grads(self):
        x_ = np.array([[0.1]])
        assert check_grad(self.acquisition_func,
                lambda x: -self.acquisition_func(x, True)[1], x_) < 1e-3
Ejemplo n.º 8
0
    def test(self):
        X_lower = np.array([0])
        X_upper = np.array([1])
        X = init_random_uniform(X_lower, X_upper, 10)
        Y = np.sin(X)
        kernel = GPy.kern.Matern52(input_dim=1)
        model = GPyModel(kernel)
        model.train(X, Y)

        x_test = init_random_uniform(X_lower, X_upper, 3)

        # Shape matching predict
        m, v = model.predict(x_test, full_cov=True)
        assert len(m.shape) == 2
        assert m.shape[0] == x_test.shape[0]
        assert m.shape[1] == 1
        assert len(v.shape) == 2
        assert v.shape[0] == x_test.shape[0]
        assert v.shape[1] == x_test.shape[0]

        # Check gradients
        dm, dv = model.predictive_gradients(x_test)
        assert len(dm.shape) == 2
        assert dm.shape[0] == x_test.shape[0]
        assert dm.shape[1] == x_test.shape[1]
        assert len(dv.shape) == 2
        assert dv.shape[0] == x_test.shape[0]
        assert dv.shape[1] == 1

        # Shape matching function sampling
        x_ = np.linspace(X_lower, X_upper, 10)
        x_ = x_[:, np.newaxis]
        funcs = model.sample_functions(x_, n_funcs=2)
        assert len(funcs.shape) == 2
        assert funcs.shape[0] == 2
        assert funcs.shape[1] == x_.shape[0]

        # Shape matching predict variance
        x_test2 = np.array([np.random.rand(1)])
        x_test1 = np.random.rand(10)[:, np.newaxis]
        var = model.predict_variance(x_test1, x_test2)
        assert len(var.shape) == 2
        assert var.shape[0] == x_test1.shape[0]
        assert var.shape[1] == 1

        # Check compatibility with all acquisition functions
        acq_func = EI(model,
                     X_upper=X_upper,
                     X_lower=X_lower)
        acq_func.update(model)
        acq_func(x_test)

        acq_func = PI(model,
                     X_upper=X_upper,
                     X_lower=X_lower)
        acq_func.update(model)
        acq_func(x_test)

        acq_func = LCB(model,
                     X_upper=X_upper,
                     X_lower=X_lower)
        acq_func.update(model)
        acq_func(x_test)

        acq_func = InformationGain(model,
                     X_upper=X_upper,
                     X_lower=X_lower)
        acq_func.update(model)
        acq_func(x_test)

        # Check compatibility with all incumbent estimation methods
        rec = BestObservation(model, X_lower, X_upper)
        inc, inc_val = rec.estimate_incumbent(None)
        assert len(inc.shape) == 2
        assert inc.shape[0] == 1
        assert inc.shape[1] == X_upper.shape[0]
        assert len(inc_val.shape) == 2
        assert inc_val.shape[0] == 1
        assert inc_val.shape[1] == 1

        rec = PosteriorMeanOptimization(model, X_lower, X_upper)
        startpoints = init_random_uniform(X_lower, X_upper, 4)
        inc, inc_val = rec.estimate_incumbent(startpoints)
        assert len(inc.shape) == 2
        assert inc.shape[0] == 1
        assert inc.shape[1] == X_upper.shape[0]
        assert len(inc_val.shape) == 2
        assert inc_val.shape[0] == 1
        assert inc_val.shape[1] == 1

        rec = PosteriorMeanAndStdOptimization(model, X_lower, X_upper)
        startpoints = init_random_uniform(X_lower, X_upper, 4)
        inc, inc_val = rec.estimate_incumbent(startpoints)
        assert len(inc.shape) == 2
        assert inc.shape[0] == 1
        assert inc.shape[1] == X_upper.shape[0]
        assert len(inc_val.shape) == 2
        assert inc_val.shape[0] == 1
        assert inc_val.shape[1] == 1