示例#1
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class GaussianProcessInterpolator:
    def __init__(self, observations):
        self.observations = observations
        self.gaussian_process = GaussianProcess(corr='cubic',
                                                theta0=1e-2,
                                                thetaL=1e-4,
                                                thetaU=1e-1,
                                                random_start=100)
        self._compute_model()

    def _compute_model(self):

        observation_points = []
        observation_results = []

        for entry in self.observations:
            observation_points.append(entry[0])
            observation_results.append(entry[1])

        observation_points_array = np.atleast_2d(observation_points)
        observation_results_array = np.array(observation_results).T

        self.gaussian_process.fit(observation_points_array,
                                  observation_results_array)

    def compute_prediction(self, observation_points):

        observation_points_array = np.atleast_2d(observation_points)

        predicted_observation_results, MSE = self.gaussian_process.predict(
            observation_points_array, eval_MSE=True)
        return predicted_observation_results, MSE
示例#2
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def interpolate_measurements(measurements, interptype='griddata'):
    pts, z = measurements_to_cartesian_points(measurements)
    gridx, gridy = make_mesh_grid(pts)
    if interptype == 'griddata':
        grid = interpolate.griddata(pts,
                                    z, (gridx, gridy),
                                    method='linear',
                                    fill_value=-3e30)
    elif interptype == 'rbf':
        ptx, pty = list(zip(*pts))
        f = interpolate.Rbf(ptx, pty, z, function='linear')
        grid = f(gridy, gridx)
    elif interptype == 'gauss':
        from sklearn.gaussian_process import GaussianProcess
        ptx, pty = list(zip(*pts))
        ptx = np.array(ptx)
        pty = np.array(pty)
        z = np.array(z)
        print(math.sqrt(np.var(z)))
        gp = GaussianProcess(regr='quadratic',
                             corr='cubic',
                             theta0=np.min(z),
                             thetaL=min(z),
                             thetaU=max(z),
                             nugget=0.05)
        gp.fit(X=np.column_stack([pty, ptx]), y=z)
        rr_cc_as_cols = np.column_stack([gridy.flatten(), gridx.flatten()])
        grid = gp.predict(rr_cc_as_cols).reshape((ncol, nrow))
    return gridx, gridy, grid
示例#3
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    def nugget_kungfu(day=0, fx_id=0, hour=3, theta0=(0.4, 1.0)):
        G = X.nm[day, fx_id, :, hour]

        G_m = G.mean(axis=0)
        G_s = G.std(axis=0)

        from sklearn.gaussian_process.gaussian_process import MACHINE_EPSILON
        nugget = (G_s / G_m) ** 2.0
        mask = ~np.isfinite(nugget)
        nugget[mask] = 10. * MACHINE_EPSILON
        nugget = nugget.ravel()
        est = GaussianProcess(corr='squared_exponential',
                              theta0=theta0,
                              #thetaL=(.5, 1.0), thetaU=(5.0, 10.0),
                              #random_start=100,
                              nugget=nugget,
                              )
        est.fit(x, G_m.ravel())
        print('est.theta_: %s' % str(est.theta_))

        pred, sigma = est.predict(np.c_[new_lats.ravel(), new_lons.ravel()],
                                  eval_MSE=True)
        pred = pred.reshape((10 * lon.shape[0], 10 * lat.shape[0])).T
        sigma = sigma.reshape((10 * lon.shape[0], 10 * lat.shape[0])).T

        fig, ([ax1, ax2, ax3, ax4]) = plt.subplots(4, 1)
        ax1.imshow(G_m, interpolation='none')
        ax1.set_ylabel('Ens mean')
        ax2.imshow(G_s, interpolation='none')
        ax2.set_ylabel('Ens std')
        ax3.imshow(pred, interpolation='none')
        ax3.set_ylabel('GP mean')
        ax4.imshow(sigma, interpolation='none')
        ax4.set_ylabel('GP sigma')
示例#4
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    def __init__(self, objective, noise, burn_in=2, grid=None):
        """
        Initialize the model. Here dim is the dimensionality of the problem.
        """
	
	# this is where the objective function stored.
        self.objective = objective

        self.burn_in = burn_in # check this many random points before fitting the GP

        self.gp = GaussianProcess(theta0=.5, thetaL=.01, thetaU=10., nugget=noise)

	# X and Y, this is where the training data for the GP stored.
        self.X = np.zeros((0, objective.ndim))
        self.Y = np.zeros((0, 1))

        if grid:
            self.grid = grid

        else:
            # If the user did not pass a grid, we construct a grid by using a
            # sobol sequence.

            self.grid = np.transpose(sobol.i4_sobol_generate(
                objective.ndim, objective.ndim * 200, 7))

            # expand the grid to cover the domain of the objective
            d = self.objective.domain
            self.grid = self.grid * (d[1] - d[0]) + d[0]
	print self.grid
def test_2d(regr=regression.constant,
            corr=correlation.squared_exponential,
            random_start=10,
            beta0=None):
    # MLE estimation of a two-dimensional Gaussian Process model accounting for
    # anisotropy. Check random start optimization.
    # Test the interpolating property.
    b, kappa, e = 5., .5, .1
    g = lambda x: b - x[:, 1] - kappa * (x[:, 0] - e)**2.
    X = np.array([[-4.61611719, -6.00099547], [4.10469096, 5.32782448],
                  [0.00000000, -0.50000000], [-6.17289014, -4.6984743],
                  [1.3109306, -6.93271427], [-5.03823144, 3.10584743],
                  [-2.87600388, 6.74310541], [5.21301203, 4.26386883]])
    y = g(X).ravel()

    thetaL = [1e-4] * 2
    thetaU = [1e-1] * 2
    gp = GaussianProcess(regr=regr,
                         corr=corr,
                         beta0=beta0,
                         theta0=[1e-2] * 2,
                         thetaL=thetaL,
                         thetaU=thetaU,
                         random_start=random_start,
                         verbose=False)
    gp.fit(X, y)
    y_pred, MSE = gp.predict(X, eval_MSE=True)

    assert_true(np.allclose(y_pred, y) and np.allclose(MSE, 0.))

    eps = np.finfo(gp.theta_.dtype).eps
    assert_true(
        np.all(gp.theta_ >= thetaL - eps))  # Lower bounds of hyperparameters
    assert_true(
        np.all(gp.theta_ <= thetaU + eps))  # Upper bounds of hyperparameters
示例#6
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    def gaussian_process(nx, ny, x, y, x_min, y_min, dx, dy):
        """
        Gausian process method. To replace kriging.
        Description:
        http://scikit-learn.org/stable/modules/generated/sklearn.gaussian_process.GaussianProcess.html#sklearn.gaussian_process.GaussianProcess.predict
        The scikit learn python library should be installed
        Should be tested
        """

        # Prediction is very sensitive to the parameters below, please use with care!
        gp = GaussianProcess(regr='quadratic',
                             corr='cubic',
                             theta0=0.1,
                             thetaL=.001,
                             thetaU=1.,
                             nugget=0.01)
        gp.fit(x, y)

        x_grid_x = np.linspace(x_min, x_min + dx * nx, nx)
        x_grid_y = np.linspace(y_min, y_min + dy * ny, ny)
        xv, yv = np.meshgrid(x_grid_x, x_grid_y)
        x_grid = np.dstack((xv.flatten(), yv.flatten()))[0]
        grid = np.reshape(gp.predict(x_grid, eval_MSE=False, batch_size=None),
                          (ny, nx))

        return grid
def ensemble(value, noise):

    #mixture = GMM(C = 100)
    mixture = GMM()
    newdataset = addNoise(noise)
    temp = np.copy(newdataset[:,-1])
    newdataset[:,-1] = newdataset[:,2]
    newdataset[:,2] = temp
    #print newdataset[:,-1], newdataset[:,3]
    for ensemble in range(0,value):
        np.random.shuffle(newdataset)
        train = np.copy(newdataset[0:-10,:])
        test =  np.copy(newdataset[-10:-1,:])
        test_pred = np.copy(test)
        mixture.fit(newdataset[0:-10,0:-2],newdataset[0:-10,-1])
        preds = mixture.predict(newdataset[-10:-1,0:-2])
        test_pred[:,-2:-1] = preds
        errorabs =  abs(dataset[-10:-1,-1]-preds)/(dataset[-10:-1,-1])
        meanerrorabs = np.mean(errorabs)
        stderrorabs = np.std(errorabs)
        print preds
        #print meanerrorabs, stderrorabs
        #plt.plot(abs(dataset[-10:-1,-1]-preds))
        #plt.ylim(-5e-12,5e-12)
        #plt.scatter(dataset[-10:-1,0],dataset[-10:-1,-1])
        #plt.plot(preds)
        #plt.show()
        np.savetxt('data/new_train_%d_snr_%d.csv'%(ensemble,noise),train,delimiter=',')
        np.savetxt('data/new_test_%d_snr_%d.csv'%(ensemble,noise),test,delimiter=',')
        np.savetxt('data/new_test_predict_%d_snr_%d.csv'%(ensemble,noise),test_pred,delimiter=',')
示例#8
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文件: interp.py 项目: nilodna/altimpy
    def kriging(self, X, y, X_pred):
        """Interpolate using Gaussian Process Regression (kriging).

        Uses the GP pacakge from 'sklearn' to interpolate spatial data points
        (2d).

        Interpolation equal noiseless case, i.e., "almost" no uncertainty in
        the observations.

        Bounds are defined assuming anisotropy.

        """
        # instanciate a Gaussian Process model
        gp = GaussianProcess(regr=self.regr,
                             corr=self.corr,
                             theta0=self.theta0,
                             thetaL=self.thetaL,
                             thetaU=self.thetaU,
                             random_start=self.rand_start,
                             nugget=self.nugget,
                             verbose=True)

        # fit to data using Maximum Likelihood Estimation of the parameters
        gp.fit(X, y)

        # evaluate the prediction points (ask for MSE as well)
        y_pred, MSE = gp.predict(X_pred, eval_MSE=True)

        return [y_pred, np.sqrt(MSE)]
 def crossValidation(self, n): 
     kf = KFold(len(self.trainX), n_folds = n)
     total_error = 0
     predictions = {}
     if self.algorithm != 'gp':
         for train,test in kf: 
             this_x = []
             this_y = []
             for i in train: 
                 this_x.append(self.trainX[i])
                 this_y.append(self.trainY[i])
             reg = self.model_for_algorithm()
             reg.fit(this_x, this_y)
             for test_i in test: 
                 predicted = reg.predict(self.trainX[test_i])
                 predictions[test_i] = predicted
                 squared_error = (predicted - self.trainY[test_i])**2
             total_error += squared_error
         self.count_accuracy(predictions)
         return total_error / len(self.trainX), predictions
     else:
         for train_idx, test_idx in kf:
             X_train = self.trainX[train_idx]
             y_train = self.trainY[train_idx]
             gp = GaussianProcess(theta0=1e-2, thetaL=1e-4, thetaU=1e-1)
             gp.fit(X_train, y_train)
             for test_i in test_idx:
                 predicted, sigma2 = gp.predict(self.trainX[test_i], eval_MSE=True)
                 predictions[test_i] = (predicted, sigma2, self.trainY[test_i])
                 sigma = np.sqrt(sigma2)
                 if self.trainY[test_i] > predicted + 1.96 * sigma or self.trainY[test_i] < predicted - 1.96 * sigma:
                     total_error += 1
         return total_error / float(len(self.trainX)), predictions
示例#10
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def train_gaussian(path):
    X, Y, weight = load_data(path, get_avg(path))
    np.save("train_X", X)
    np.save("train_Y", Y)
    gp = GaussianProcess()
    gp.fit(X, Y)
    return gp
示例#11
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def test(filename, reg):
    # initial the parameters
    #(X, y) = data_read('./data/eta_reg_605603_p0.data');
    # (X, y) = load_svmlight_file('./data/eta_reg_605603_p0.data');
    (X, y) = load_svmlight_file(filename);
    print("Data imported!");

    # divide into training and test_pyGPs datasets
    ratio = 0.8;
    num = len(y);
    idx = range(num);
    random.shuffle(idx);
    tn = int(np.floor(num*ratio));
    tr_idx = idx[:tn]
    te_idx = idx[tn:]
    # X_train = X[tr_idx]
    # y_train = y[tr_idx]
    tnum = int(np.floor(0.2*num))
    X_train = X[tr_idx[:tnum]]
    y_train = y[tr_idx[:tnum]]    
    X_test = X[te_idx]
    y_test = y[te_idx]

    # train linear ridge regression model
    print("Model training!");
    p1 = float(reg);
    clf = GaussianProcess(corr='squared_exponential');
    # clf.fit(list(X_train), y_train);
    clf.fit(X_train.toarray() , y_train);  
    abe = np.mean( abs(clf.predict(X_test.toarray()) - y_test)/y_test )
    #np.mean((clf.predict(X_test) - y_test) ** 2))
    print("Absolute error is: %.2f" % abe );
def check2d(X, regr=regression.constant, corr=correlation.squared_exponential,
            random_start=10, beta0=None):
    """
    MLE estimation of a two-dimensional Gaussian Process model accounting for
    anisotropy. Check random start optimization.

    Test the interpolating property.
    """
    b, kappa, e = 5., .5, .1
    g = lambda x: b - x[:, 1] - kappa * (x[:, 0] - e) ** 2.

    y = g(X).ravel()

    thetaL = [1e-4] * 2
    thetaU = [1e-1] * 2
    gp = GaussianProcess(regr=regr, corr=corr, beta0=beta0,
                         theta0=[1e-2] * 2, thetaL=thetaL,
                         thetaU=thetaU,
                         random_start=random_start, verbose=False)
    gp.fit(X, y)
    y_pred, MSE = gp.predict(X, eval_MSE=True)

    assert_true(np.allclose(y_pred, y) and np.allclose(MSE, 0.))

    assert_true(np.all(gp.theta_ >= thetaL)) # Lower bounds of hyperparameters
    assert_true(np.all(gp.theta_ <= thetaU)) # Upper bounds of hyperparameters
def test_2d_2d(regr=regression.constant, corr=correlation.squared_exponential,
               random_start=10, beta0=None):
    """
    MLE estimation of a two-dimensional Gaussian Process model accounting for
    anisotropy. Check random start optimization.

    Test the GP interpolation for 2D output
    """
    b, kappa, e = 5., .5, .1
    g = lambda x: b - x[:, 1] - kappa * (x[:, 0] - e) ** 2.
    f = lambda x: np.vstack((g(x), g(x))).T
    X = np.array([[-4.61611719, -6.00099547],
                  [4.10469096, 5.32782448],
                  [0.00000000, -0.50000000],
                  [-6.17289014, -4.6984743],
                  [1.3109306, -6.93271427],
                  [-5.03823144, 3.10584743],
                  [-2.87600388, 6.74310541],
                  [5.21301203, 4.26386883]])
    y = f(X)
    gp = GaussianProcess(regr=regr, corr=corr, beta0=beta0,
                         theta0=[1e-2] * 2, thetaL=[1e-4] * 2,
                         thetaU=[1e-1] * 2,
                         random_start=random_start, verbose=False)
    gp.fit(X, y)
    y_pred, MSE = gp.predict(X, eval_MSE=True)

    assert_true(np.allclose(y_pred, y) and np.allclose(MSE, 0.))
示例#14
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    def optimize(self, f, beta=1, init_num=10, restarts=100, \
             opt_fx=float('-inf'), torelance=1e-8, iteration=1000):
        X = self.generate_random_variables(init_num)
        Fx = [f(x) for x in X]

        x_best = self.lower
        fx_best = min(Fx)
        acq_values = []
        num_evals = 0

        for i in range(iteration):
            gp = GaussianProcess(theta0=[0.1]*self.dim)
            gp.fit(X, Fx)

            x_new, acq_value = self.max_acquisition(gp, beta=beta, restarts=restarts)
            fx_new = f(x_new)
            num_evals += 1

            if fx_new < fx_best:
                x_best = x_new
                fx_best = fx_new
                print("%d \t %s \t %s" % (i, fx_best, x_best))
                if np.abs(fx_best - opt_fx) < torelance : break

            #X = np.vstack((X, x_new))
            #Fx = np.hstack((Fx, fx_new))
            #acq_values.append(acq_value)

        print("#Evals=%d \t\t f(x*)=%s" % (num_evals, str(fx_best)))
        return (x_best, fx_best)
示例#15
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class GaussianProcessRigression(object):

	def __init__(self,data_frame,test_df):
		self.df=data_frame
		self.test=test_df

	def fitModel(self,predictors,output_var):
		self.predictors=predictors
		self.output_var=output_var
		self.gp = GaussianProcess(corr='cubic', theta0=1e-2, thetaL=1e-4, thetaU=1e-1, random_start=100)
		self.gp.fit(self.df[predictors].values,self.df[output_var].values)
		self.y_pred, self.MSE = self.gp.predict(self.test[predictors], eval_MSE=True)
		self.sigma = np.sqrt(self.MSE)

	#works only when you have single parameter for predictors only 
	#as for multiple parameters doesn't make sense to make a 2D curve.
	def givePlot(self,xlabel='$x$',ylabel='$f(x)$'):
		fig = pl.figure()
		pl.plot(self.test[self.predictors], self.test[self.output_var], 'r:', label=u'Actual curve')
		# pl.plot(X, y, 'r.', markersize=10, label=u'Observations')
		pl.plot(self.test[self.predictors], self.y_pred, 'b-', label=u'Prediction')
		pl.fill(np.concatenate([self.test[self.predictors], self.test[self.output_var]]), \
		        np.concatenate([self.y_pred - 1.9600 * self.sigma,
		                       (self.y_pred + 1.9600 * self.sigma)[::-1]]), \
		        alpha=.5, fc='b', ec='None', label='95% confidence interval')
		pl.xlabel(xlabel)
		pl.ylabel(ylabel)
		pl.ylim(-10, 20)
		pl.legend(loc='upper left')
		pl.show()
示例#16
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def gp_lc_fit(t, m, e, npoints=10000, plot=True, theta=0.15):
    '''
    Use Gaussian process regression to fit a functional
     form to a supernova lightcurve.
    t, m, e: 1D arrays for time, mag, and error
    theta: the autcorrelation timescale parameter. If the model needs to have more
            flexture, increase theta.  If it needs less, decrease theta.
    returns: t, mag, err arrays of size npoints
    '''
    edge = 1.0  # predict beyond the data by this amount on either side

    X = np.atleast_2d( t ).T  # need a 2D array for skl procedures
    y = np.array(m)
    e = np.array(e)
    x = np.atleast_2d( np.linspace(t[0]-edge, t[-1]+edge, npoints)).T
    xf = x.flatten()

    gp = GaussianProcess(regr='linear', nugget=(e/y)**2, theta0=theta)
    gp.fit(X,y)
    y_pred, MSE = gp.predict(x, eval_MSE=True)
    ep = MSE**.5  # prediction error estimate

    if plot:
        plt.figure()
        plt.errorbar( t, m, yerr=e, fmt='b.' )
        plt.plot(xf, y_pred, 'g', lw=2)
        plt.fill_between( xf, y_pred+ep, y_pred-ep, alpha=0.5, color='g' )
        plt.gca().invert_yaxis()
        plt.title('Photometry, GP model, and errors')
        plt.show()
    return xf, y_pred, ep
示例#17
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    def _trainGP(self, colors, nfit=-1):
        """Train the mapping between eigenvalues and color via Gaussian Process
        
           @param colors    array of galaxy colors
           @param nfit      number of eigenvalues to use in the mapping (if =-1 use all)
        """
        self._gp = GaussianProcess(corr=self._corr_type, theta0=self._theta0)

        if (nfit < 0):
            nfit = self.eigenvalue_coeffs.shape[1]
            print "Using all", nfit, "eigenvalues in GP"

        # BK note:
        # Make sure we only include unique color values
        # Used method for taking unique rows in array found here:
        # http://stackoverflow.com/questions/16970982/find-unique-rows-in-numpy-array
        data = colors
        find_unique = np.ascontiguousarray(data).view(
            np.dtype((np.void, data.dtype.itemsize * data.shape[1])))
        unique_idx = np.unique(find_unique, return_index=True)[1]
        print "Number of unique colors in SED set", len(
            unique_idx), "total number of SEDs =", len(colors)

        # Train and predict eigenvalues for this color set
        self._gp.fit(colors[unique_idx],
                     self.eigenvalue_coeffs[unique_idx, :nfit])
class GaussianProcessInterpolator:

    def __init__(self, observations):
        self.observations = observations
        self.gaussian_process = GaussianProcess(corr='cubic', theta0=1e-2, thetaL=1e-4, thetaU=1e-1, random_start=100)
        self._compute_model()

    def _compute_model(self):

        observation_points = []
        observation_results = []

        for entry in self.observations:
            observation_points.append(entry[0])
            observation_results.append(entry[1])

        observation_points_array = np.atleast_2d(observation_points)
        observation_results_array = np.array(observation_results).T

        self.gaussian_process.fit(observation_points_array, observation_results_array)

    def compute_prediction(self, observation_points):

        observation_points_array = np.atleast_2d(observation_points)

        predicted_observation_results, MSE = self.gaussian_process.predict(observation_points_array, eval_MSE=True)
        return predicted_observation_results, MSE
示例#19
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def test_2d_2d(regr=regression.constant,
               corr=correlation.squared_exponential,
               random_start=10,
               beta0=None):
    """
    MLE estimation of a two-dimensional Gaussian Process model accounting for
    anisotropy. Check random start optimization.

    Test the GP interpolation for 2D output
    """
    b, kappa, e = 5., .5, .1
    g = lambda x: b - x[:, 1] - kappa * (x[:, 0] - e)**2.
    f = lambda x: np.vstack((g(x), g(x))).T
    X = np.array([[-4.61611719, -6.00099547], [4.10469096, 5.32782448],
                  [0.00000000, -0.50000000], [-6.17289014, -4.6984743],
                  [1.3109306, -6.93271427], [-5.03823144, 3.10584743],
                  [-2.87600388, 6.74310541], [5.21301203, 4.26386883]])
    y = f(X)
    gp = GaussianProcess(regr=regr,
                         corr=corr,
                         beta0=beta0,
                         theta0=[1e-2] * 2,
                         thetaL=[1e-4] * 2,
                         thetaU=[1e-1] * 2,
                         random_start=random_start,
                         verbose=False)
    gp.fit(X, y)
    y_pred, MSE = gp.predict(X, eval_MSE=True)

    assert_true(np.allclose(y_pred, y) and np.allclose(MSE, 0.))
 def gaussian_process(x_train, y_train, x_test):
     def vector_2d(array):
         return np.array(array).reshape((-1, 1))
     
     import warnings
 
     
     
     def fxn():
         warnings.warn("deprecated", DeprecationWarning)
     with warnings.catch_warnings():
         warnings.simplefilter("ignore")
         fxn()
         
         x_train = vector_2d(x_train)
         y_train = vector_2d(y_train)
         x_test = vector_2d(x_test)
         # Train gaussian process
         gp = GaussianProcess(corr='squared_exponential',
                              theta0=1e-1, thetaL=1e-3, thetaU=1)
         gp.fit(x_train, y_train)
 
         # Get mean and standard deviation for each possible
         # number of hidden units
         y_mean, y_var = gp.predict(x_test, eval_MSE=True)
         y_std = np.sqrt(vector_2d(y_var))
 
     return y_mean, y_std
示例#21
0
def noiseless():
  X = np.atleast_2d([1.,3.,5.,6.,7.,8.,]).T
  # observations
  y = f(X).ravel() # reshape to 1-D
  # mesh the input space to cover all points to predict f(x) and the MSE
  x = np.atleast_2d(np.linspace(0,10,1000)).T # and flatten
  # instantiate gauss process
  gp = GaussianProcess(corr='cubic', theta0=1e-2, thetaL=1e-4,
                       thetaU=1e-1, random_start=100)
  # fit to data using maximum likelihood estimation of params
  gp.fit(X,y)
  # make predictions on meshed x-axis, also return MSE
  y_pred, MSE = gp.predict(x, eval_MSE=True)
  sigma = np.sqrt(MSE)
  
  # plot
  fig = plt.figure()
  plt.plot(x, f(x), 'r:', label=u'$f(x) = x\,\sin(x)$')
  plt.plot(X, y, 'r.', markersize=10, label=u'Observations')
  plt.plot(x, y_pred, 'b-', label=u'Prediction')
  # fill the space between the +/-MSE
  plt.fill(np.concatenate([x, x[::-1]]), # reverse order of x
           np.concatenate([y_pred - 1.9600 * sigma,
                          (y_pred + 1.9600 * sigma)[::-1]]),
           alpha=0.5, fc='b', ec='None', label='95% confidence interval')
           # shade, fill color, edge color
  plt.title('Noiseless case')
  plt.xlabel('$x$')
  plt.ylabel('$f(x)$')
  plt.ylim(-10, 20)
  plt.legend(loc='upper left')
  return
示例#22
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def train_gaussian(path):
    X, Y, weight = load_data(path, get_avg(path))
    np.save("train_X", X)
    np.save("train_Y", Y)
    gp = GaussianProcess()
    gp.fit(X, Y)
    return gp
示例#23
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 def update_GP(self,meas_locations):
     # define grid to evaluate stuff on
     #res = 100
     sensornoise=.000001
     noise= sensornoise*np.random.randn(meas_locations.shape[0])
     measurements = self.simulatedsurface(meas_locations) + noise
     print meas_locations
     print measurements
     [self.meas_locations,self.new_measurements]=self.averageduplicates(meas_locations,measurements)
     # Instanciate and fit Gaussian Process Model
     gp = GaussianProcess(corr='squared_exponential',
         #theta0=10e-1,
         #thetaL=10e-1, ##thetaU=1e-1,
         nugget=(sensornoise/self.new_measurements) ** 2
     )
     # Observations
     
     print noise
     
     # Don't perform MLE or you'll get a perfect prediction for this simple example!
     gp.fit(self.meas_locations, self.new_measurements)
     #evaluate the prediction and its MSE on a grid
     y_pred, MSE = gp.predict(self.xgrid, eval_MSE=True)
     sigma = np.sqrt(MSE)
     y_pred = y_pred.reshape((self.res, self.res))
     sigma = sigma.reshape((self.res, self.res))
     self.model=y_pred
     self.uncertainty=sigma
     return [y_pred,sigma]
def gaussian_fit_likelihood(x, y):
    # Remove duplicates
    n_dupl = 0
    d = dict()
    for i in range(len(x)):
      try:
        if d[x[i]] != y[i]:
          n_dupl += 1
          d.pop(x[i], None)
      except:
        d[x[i]] = y[i]

    ret = [n_dupl]

    try:  
      newX = np.atleast_2d(d.keys()).T
      newY = np.array(d.values()).ravel()
      g = GaussianProcess(theta0=1e5, thetaL=1e-4, thetaU=1e-1)
      #g = GaussianProcess()
      g.fit(newX, newY)
      err = newY - g.predict(newX)
      p = pearsonr(err, newX)
      ret += [g.reduced_likelihood_function_value_]
      ret += p
    except:
      #fp = open("bad_pt.txt", "a")
      #fp.write("1")
      #fp.close()
      ret += [0.0, 0.0, 0.0]
   
    print ret
    return ret
示例#25
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文件: interp.py 项目: fspaolo/altimpy
    def kriging(self, X, y, X_pred):
        """Interpolate using Gaussian Process Regression (kriging).

        Uses the GP pacakge from 'sklearn' to interpolate spatial data points
        (2d).

        Interpolation equal noiseless case, i.e., "almost" no uncertainty in
        the observations.

        Bounds are defined assuming anisotropy.

        """
        # instanciate a Gaussian Process model
        gp = GaussianProcess(regr=self.regr, corr=self.corr,
                             theta0=self.theta0, thetaL=self.thetaL,
                             thetaU=self.thetaU, random_start=self.rand_start,
                             nugget=self.nugget, verbose=True)

        # fit to data using Maximum Likelihood Estimation of the parameters
        gp.fit(X, y)

        # evaluate the prediction points (ask for MSE as well)
        y_pred, MSE = gp.predict(X_pred, eval_MSE=True)

        return [y_pred, np.sqrt(MSE)]
def test_2d(regr=regression.constant, corr=correlation.squared_exponential,
            random_start=10, beta0=None):
    # MLE estimation of a two-dimensional Gaussian Process model accounting for
    # anisotropy. Check random start optimization.
    # Test the interpolating property.
    b, kappa, e = 5., .5, .1
    g = lambda x: b - x[:, 1] - kappa * (x[:, 0] - e) ** 2.
    X = np.array([[-4.61611719, -6.00099547],
                  [4.10469096, 5.32782448],
                  [0.00000000, -0.50000000],
                  [-6.17289014, -4.6984743],
                  [1.3109306, -6.93271427],
                  [-5.03823144, 3.10584743],
                  [-2.87600388, 6.74310541],
                  [5.21301203, 4.26386883]])
    y = g(X).ravel()

    thetaL = [1e-4] * 2
    thetaU = [1e-1] * 2
    gp = GaussianProcess(regr=regr, corr=corr, beta0=beta0,
                         theta0=[1e-2] * 2, thetaL=thetaL,
                         thetaU=thetaU,
                         random_start=random_start, verbose=False)
    gp.fit(X, y)
    y_pred, MSE = gp.predict(X, eval_MSE=True)

    assert_true(np.allclose(y_pred, y) and np.allclose(MSE, 0.))

    eps = np.finfo(gp.theta_.dtype).eps
    assert_true(np.all(gp.theta_ >= thetaL - eps))  # Lower bounds of hyperparameters
    assert_true(np.all(gp.theta_ <= thetaU + eps))  # Upper bounds of hyperparameters
示例#27
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def initGP():
    """Do simulations with random pi,z and create GP, X, y"""
    poolsize = 68
    pool = Pool.spawn(Genome.open(NN_STRUCTURE_FILE), poolsize, std=10)
    X = []
    for i, org in enumerate(pool):
        org.mutate()
        genome = org.genome
        w = genome.weights
        z = [np.random.uniform(0, 0.3)]
        reward = cliff(genome, z)

        while reward <= 0 and len(X) < poolsize / 2:
            #Train input policies to reach the goal.
            org.mutate()
            genome = org.genome
            w = genome.weights
            reward = cliff(genome, z)

        if not len(X):
            X = np.atleast_2d(w + z)
            y = np.atleast_2d([reward])
        else:
            X = np.append(X, [w + z], axis=0)
            y = np.append(y, [reward])

    # Initialize GP with kernel parameters.
    GP = GaussianProcess(theta0=0.1, thetaL=.001, thetaU=1.)

    GP.fit(X, y)

    return GP, X, y
def GaussianProcess_interp(points, values, xi, theta0=0.1, thetaL=0.001, thetaU=1.0, nugget=0.01):
    x_points = np.array(points)[:, 0]
    y_points = np.array(points)[:, 1]
    gp = GaussianProcess(theta0=theta0, thetaL=thetaL, thetaU=thetaU, nugget=nugget)
    gp.fit(X=np.column_stack([x_points, y_points]), y=np.array(values))
    xi_as_cols = np.column_stack([xi[0].flatten(), xi[1].flatten()])
    z = gp.predict(xi_as_cols).reshape(xi[0].shape)
    return z
示例#29
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 def __init__(self, observations):
     self.observations = observations
     self.gaussian_process = GaussianProcess(corr='cubic',
                                             theta0=1e-2,
                                             thetaL=1e-4,
                                             thetaU=1e-1,
                                             random_start=100)
     self._compute_model()
示例#30
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文件: gp.py 项目: jmandreoli/PYTOOLS
 def __init__(self,data,theta0=None,thetaL_r=None,thetaU_r=None,**ka):
     self.data = data
     gp = GaussianProcess(theta0=theta0,thetaL=thetaL_r*theta0,thetaU=thetaU_r*theta0,**ka)
     gp.fit(data.x[:,newaxis],data.y)
     def q(x,regr=gp.get_params()['regr'],beta=gp.reduced_likelihood_function()[1]['beta']):
         return dot(regr(x),beta)
     self.q = q
     self.predict = gp.predict
def _predict_coordinate(segment, coord, times, t1, sigma=10., **kwargs):

    times = np.atleast_2d(times).T
    prev = segment[coord]
    nugget = (sigma / (prev + sigma)) ** 2
    gp = GaussianProcess(nugget=nugget, **kwargs)
    gp.fit(times, prev)
    return gp.predict(t1, eval_MSE=True)
示例#32
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def learning(regression,correlation,x_train,y_train):

	print("Learning")

	X_train, Y_train = numpy.asarray(x_train) , numpy.asarray(y_train)

	gp = GaussianProcess(corr=correlation, normalize=True, regr=regression, thetaL=1e-2, thetaU=1.0)
	gp.fit(X_train, Y_train)
	return gp
def gaussReg(metrics, densities): 
  #  metrics = [[0, 0], [2, 2]] #List of lists of metrics calculated 
   # densities =  [0.5, 2.5] #The corresponding densities 
    
    gp = GaussianProcess(corr='absolute_exponential', theta0=1e-1,
                     thetaL=1e-3, thetaU=1,
                     random_start=100)    #Change these parameters to get better fit...            
    gp.fit(metrics, densities)
    return gp
def gaussReg(metrics, densities): 
  #  metrics = [[0, 0], [2, 2]] #List of lists of metrics calculated 
   # densities =  [0.5, 2.5] #The corresponding densities 
    
    gp = GaussianProcess(corr='absolute_exponential', theta0=1e-1,
                     thetaL=1e-3, thetaU=1,
                     random_start=100)    #Change these parameters to get better fit...            
    gp.fit(metrics, densities)
    return gp
示例#35
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def gpTest1():
    xx = np.array([[10.]])
    X = np.array([[1., 3., 5., 6., 7., 8., 9.]]).T
    y = (X * np.sin(X)).ravel()
    gp = GaussianProcess(theta0=0.1, thetaL=.001, thetaU=1.)
    gp.fit(X, y)
    p = gp.predict(xx)
    print(X, y)
    print(p, xx * np.sin(xx))
def Gaussian_Process_Regression(features, target):
    print("===== GaussianProcess =====")
    print("[INFO] Training the Classifier")

    classifier = GaussianProcess(theta0=0.1, thetaL=0.001, thetaU=1.0)
    classifier.fit(features, target)

    print("Saving the classifier")
    data_io.save_model(classifier)
示例#37
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def Gaussian_Process_Regression(features, target):
    print("===== GaussianProcess =====")
    print("[INFO] Training the Classifier")
    
    classifier = GaussianProcess(theta0=0.1, thetaL=0.001, thetaU=1.0)
    classifier.fit(features, target)
    
    print("Saving the classifier")
    data_io.save_model(classifier)
示例#38
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    def get_best_params(model,
                        training,
                        testing,
                        non_relevant_count=100,
                        **kwargs):
        """
        Search for the best set of parameters in the model

        use ParameterTuning().getBestParameters(model,parA=(0,10,0.1,3)...)
        (min,max,step,default)
        """
        # Create a grid of parameters
        kwargs = kwargs or model.param_details()
        grid = zip(
            *(x.flat
              for x in np.mgrid[[slice(*row[:3]) for row in kwargs.values()]]))
        m_instance = model()
        values = {
            k: ParameterTuning.tune(m_instance, training, testing,
                                    non_relevant_count,
                                    **dict(zip(kwargs.keys()[:2], k)))
            for k in zip(*(v[:2] for v in kwargs.values()))
        }

        gp = GaussianProcess(theta0=.1, thetaL=.001, thetaU=5.)

        # To make it reasonable we limit the number of iterations
        for i in xrange(0, ParameterTuning.__max_iterations):

            # Get a list of parameters and the correspondent result
            param, response = zip(*values.items())

            # Fit the GaussianProcess model with the parameters and results
            gp.fit(np.array(param), np.array(response).T)

            # Get prediction
            y_predicted, mse = gp.predict(grid, eval_MSE=True)

            # get upper confidence interval. 2.576 z-score corresponds to 99th
            # percentile
            ucb_u = y_predicted + np.sqrt(mse) * ParameterTuning.__z_score

            next_list = zip(ucb_u, grid)
            next_list.sort(reverse=True)
            new_x = next_list[0][1]

            if new_x not in values:
                values[new_x] = ParameterTuning.tune(
                    m_instance, training, testing,
                    **{k: v
                       for k, v in zip(kwargs, new_x)})
            else:
                break
        sv = sorted(values.items(), cmp=lambda x, y: cmp(y[1], x[1]))
        assert sv[0][1] > sv[-1][1], "Sorted from lowest to highest"
        return {k: v for k, v in zip(kwargs, sv[0][0])}
示例#39
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def run_test(training_size,prediction_size,function_name,corr_kernel,n_cluster,prior='GCP'):
	scoring_function = functions[function_name]
	parameter_bounds = all_parameter_bounds[function_name]

	x_training = []
	y_training = []
	for i in range(training_size):
		x = [np.random.uniform(parameter_bounds[j][0],parameter_bounds[j][1]) for j in range(parameter_bounds.shape[0])]
		x_training.append(x)
		y_training.append(scoring_function(x)[0])
	if(isInt[function_name]):
		x_training,y_training = compute_unique2( np.asarray(x_training,dtype=np.int32) , np.asarray( y_training) )

	candidates = []
	real_y = []
	for i in range(prediction_size):
		x = [np.random.uniform(parameter_bounds[j][0],parameter_bounds[j][1]) for j in range(parameter_bounds.shape[0])]
		candidates.append(x)
		real_y.append(scoring_function(x)[0])
	real_y = np.asarray(real_y)
	if(isInt[function_name]):
		candidates = np.asarray(candidates,dtype=np.int32)

	if(prior == 'GP'):
		gp = GaussianProcess(theta0=.1 *np.ones(parameter_bounds.shape[0]),
							 thetaL=0.001 * np.ones(parameter_bounds.shape[0]),
							 thetaU=10. * np.ones(parameter_bounds.shape[0]),
							 random_start=5,
							 nugget=nugget)
		gp.fit(x_training,y_training)
		pred = gp.predict(candidates)
		likelihood = gp.reduced_likelihood_function_value_

	else:
		gcp = GaussianCopulaProcess(nugget=nugget,
		                            corr=corr_kernel,
		                            random_start=5,
		                            normalize=True,
		                            coef_latent_mapping=coef_latent_mapping,
		                            n_clusters=n_clusters)
		gcp.fit(x_training,y_training)
		likelihood = gcp.reduced_likelihood_function_value_
		
		if not (integratedPrediction):
			pred = gcp.predict(candidates)
		else:
			pred,_,_,_ = gcp.predict(candidates,
									eval_MSE = True,
									eval_confidence_bounds=True,
									integratedPrediction=True)

	mse = np.mean( (pred - real_y)**2. )
	# Normalize 
	mse = mse / ( np.std(real_y) **2. )
	likelihood = np.exp(likelihood)
	return [mse,likelihood]
def gaussReg(metrics, densities): 
    """Runs a Gaussian Regression algorithm on metrics, and array of metrics, 
        and densities, the corresponding densities."""
  #  metrics = [[0, 0], [2, 2]] #List of lists of metrics calculated 
   # densities =  [0.5, 2.5] #The corresponding densities 
    
    gp = GaussianProcess( regr = 'linear', corr = 'absolute_exponential', theta0 = 1, thetaL=1, thetaU=10)    #Change these parameters to get better fit...            
   
    gp.fit(metrics, densities)
    return gp
def getAllData():
    global allData, costModel, costModelInputScaler, costModelOutputScaler
    if not allData or not costModel:
        ## COST MODEL
        spamReader = csv.reader(open('time_results.csv', 'rb'), delimiter=';', quotechar='"')

        x = []
        y = []
        for row in spamReader:
            x.append([float(row[1]),float(row[2])])
            y.append([float(row[3]) + random.random()])
        x = array(x)
        y = array(y)
        input_scaler = preprocessing.StandardScaler().fit(x)
        scaled_training_set = input_scaler.transform(x)

                # Scale training data
        output_scaler = preprocessing.StandardScaler(with_std=False).fit(y)
        adjusted_training_fitness = output_scaler.transform(y)
        
        regr = GaussianProcess(corr='squared_exponential', theta0=1e-1,
                         thetaL=1e-5, thetaU=3,
                         random_start=400)
        regr.fit(scaled_training_set, adjusted_training_fitness)
        costModel = regr
        costModelInputScaler = input_scaler
        costModelOutputScaler = output_scaler
        ## cores, accuracy, exeuction time
        spamReader = csv.reader(open('AnsonCores.csv', 'rb'), delimiter=',', quotechar='"')
        cores = {11:{}}
        for row in spamReader:
            cores[11][int(row[1])] = int(row[0])

        maxcores = cores
        spamReader = csv.reader(open('AnsonExec.csv', 'rb'), delimiter=';', quotechar='"')

        allData = {}
        for row in spamReader:
            row_0 = int(row[0])
            row_1 = int(row[1])
            row_2 = int(row[2])
            row_3 = float(row[3])
            row_4 = float(row[4])
            data = [cores[row_0][row_1],row_3,row_4]
            
            try:
                try:
                    allData[row_0][row_1][row_2] = data
                except:
                    allData[row_0][row_1] = {row_2:data}
            except:
                allData[row_0] = {row_1:{row_2:data}}
        #spamReader.close()
    #print allData
    return allData
示例#42
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def make_a_perfect_model(pairNo, x, X, y):
    """Make a GaussianProcess model for data without noise (It
    complains for TDC dataset though!)"""
    gp = GaussianProcess(theta0=1e-3, thetaL=1e-3, thetaU=1, random_start=500)
    # Fit to data using Maximum Likelihood Estimation of the parameters
    gp.fit(X, y)

    # Make the prediction on the meshed x-axis (ask for MSE as well)
    y_pred, MSE = gp.predict(x, eval_MSE=True)
    sigma = np.sqrt(MSE)
    return gp, y_pred, sigma
示例#43
0
def compareStats(rawData, theta):

    data = [[rawData["lon"][i], rawData["lat"][i]] for i in range(len(rawData["lon"]))]
    labels = rawData["classif"]

    data, labels = mapping.cleanDoubles(data, labels)

    rfc = GaussianProcess(regr="linear", theta0=theta)
    rfc.fit(data, labels)
    scores = cross_val_score(rfc, data, labels, cv=5)
    print ("Accuracy: %0.2f (+/- %0.2f)" % (scores.mean(), scores.std() * 2))
def learning(regression,correlation,trainingsize,Quantum_enrgy,Parameters):
	x_train, y_train, x_test, y_test = load_data(Quantum_enrgy,Parameters,trainingsize)
	print len(x_train)
	print len(y_train)

	X_train, y_train = numpy.asarray(x_train) , numpy.asarray(y_train)
	X_val, y_val = numpy.asarray(x_test) , numpy.asarray(y_test)

	print("Generating GP")
	gp = GaussianProcess(corr=correlation, normalize=True, regr=regression, thetaL=1e-2, thetaU=1.0)
	gp.fit(X_train, y_train)
	return gp, x_train, y_train, x_test, y_test
示例#45
0
class GaussianProcess(object):
    def __init__(self, nugget=0.1):
        self.nugget = nugget

    def fit(self, chips):
        X = pandas.DataFrame([[chip.X, chip.Y] for chip in chips])
        y = [chip.gnd for chip in chips]
        self.gp = GaussianProcess(nugget=self.nugget)
        self.gp.fit(X, y)

    def predict(self, chip):
        return self.gp.predict([chip.X, chip.Y])
示例#46
0
def gpo1d(objective):
	besto = 0.0
	bestp = None

	D = 1
	

	X = []
	y = []


	params = abs(rand(D)) * 10.0
	X.append(params)
	y.append(objective([params, params]))

	params = abs(rand(D)) * 10.0
	X.append(params)
	y.append(objective([params, params]))

	print "X = ", X
	print "y = ", y


	while(True):
		gp = GaussianProcess(corr='cubic', theta0=1e-2, thetaL=1e-4, thetaU=1e-1, random_start=100)
		gp.fit(X, y)   

		#XX, YY = np.meshgrid(np.linspace(0, 10, 20), np.linspace(0, 10, 20))
		#print XX

		XX = numpy.linspace(0, 10, 100)
		y_pred, mse = gp.predict(np.c_[XX], eval_MSE=True)
		sigma = np.sqrt(mse)
		#Z = np.array(Z)
		#Z = Z.reshape(XX.shape)
		
	
		pl.plot(X,y, 'xk')
		pl.plot(XX, y_pred, 'b-', label=u'Prediction')
		pl.fill(np.concatenate([XX, XX[::-1]]), np.concatenate([y_pred - 1.9600 * sigma, (y_pred + 1.9600 * sigma)[::-1]]), alpha=.5, fc='b', ec='None', label='95% confidence interval')
		#CS = pl.contour(XX, YY, Z, 20, colours='k')
		pl.show()

		# Find next point to evaluate
		# Evaluate and append to X and y
		for k in xrange(2):
			params = abs(rand(D)) * 10.0
			X.append(params)
			y.append(objective([params, params]))
		


	return bestp
示例#47
0
class GaussianProcess(object):
    def __init__(self, nugget=0.1):
        self.nugget = nugget
        
    def fit(self, chips):
        X = pandas.DataFrame([[chip.X, chip.Y] for chip in chips])
        y = [chip.gnd for chip in chips]        
        self.gp = GaussianProcess(nugget=self.nugget)
        self.gp.fit(X, y)
    
    def predict(self, chip):
        return self.gp.predict([chip.X, chip.Y])
示例#48
0
def fit_GP(all_sp, miss_rate, train_rate):
    # seperate train and test_pyGPs data, unobserved speeds are set as -1
    train_sp, test_sp = sep_train(all_sp, miss_rate, train_rate)

    # calculate historical mean
    his_mean = calc_mean(train_sp)

    # fit and predict
    mape_dates = defaultdict(lambda: 0)
    rmse_dates = defaultdict(lambda: 0)

    for key in test_sp:

        # X: historical mean, Y: current speed
        miss_links = list()
        miss_true_sp = list()
        miss_mean_sp = list()
        obser_links = list()
        obser_true_sp = list()  # Y
        obser_mean_sp = list()  # X

        for l in range(len(test_sp[key])):
            if test_sp[key][l] == -1:
                miss_links.append(l)
                miss_true_sp.append(all_sp[int(key[0])][int(key[1])][l])
                miss_mean_sp.append(his_mean[l])
            else:
                obser_links.append(l)
                obser_true_sp.append(all_sp[int(key[0])][int(key[1])][l])
                obser_mean_sp.append(his_mean[l])

        X = np.atleast_2d(obser_mean_sp).T
        Y = np.array(obser_true_sp).T
        gp = GaussianProcess(corr="absolute_exponential")
        gp.fit(X, Y)

        x = np.atleast_2d(miss_mean_sp).T
        predict_sp, MSE = gp.predict(x, eval_MSE=True)
        sigma = np.sqrt(MSE)

        mape = 0.0
        rmse = 0.0
        for i in range(len(miss_links)):
            rmse += (predict_sp[i] - miss_true_sp[i]) ** 2
            mape += np.abs(predict_sp[i] - miss_true_sp[i]) / miss_true_sp[i]
        rmse = np.sqrt(rmse / len(miss_links))
        mape = mape / len(miss_links)

        mape_dates[key] = mape
        rmse_dates[key] = rmse

    return (mape_dates, rmse_dates)
示例#49
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def test_1d(regr=regression.constant, corr=correlation.squared_exponential,
            random_start=10, beta0=None):
    # MLE estimation of a one-dimensional Gaussian Process model.
    # Check random start optimization.
    # Test the interpolating property.
    gp = GaussianProcess(regr=regr, corr=corr, beta0=beta0,
                         theta0=1e-2, thetaL=1e-4, thetaU=1e-1,
                         random_start=random_start, verbose=False).fit(X, y)
    y_pred, MSE = gp.predict(X, eval_MSE=True)
    y2_pred, MSE2 = gp.predict(X2, eval_MSE=True)

    assert_true(np.allclose(y_pred, y) and np.allclose(MSE, 0.)
                and np.allclose(MSE2, 0., atol=10))
示例#50
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 def create_gp_and_fit(x, y, max_try=100):
     # この辺怪しい
     theta0 = 0.1
     for i in range(max_try + 1):
         try:
             gp = GaussianProcess(theta0=theta0)
             gp.fit(x, y)
             return gp
         except Exception as e:
             theta0 *= 10
             if i == max_try:
                 print(theta0)
                 raise e
示例#51
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def noisy():
    X = np.linspace(0.1, 9.9, 20)
    X = np.atleast_2d(X).T
    # observations and noise
    y = f(X).ravel()
    dy = 0.5 + 1.0 * np.random.random(y.shape)
    noise = np.random.normal(0, dy)
    y += noise
    # mesh the input space for evaluation of the function & its prediction and MSE
    x = np.atleast_2d(np.linspace(0, 10, 1000)).T
    # instantiate a gauss process
    gp = GaussianProcess(corr='squared_exponential',
                         theta0=1e-1,
                         thetaL=1e-3,
                         thetaU=1,
                         nugget=(dy / y)**2,
                         random_start=100)
    # nugget specifies std of noise, Tikhonov regularization
    # allows robust recovery of underlying function
    # from noisy data
    # fit to GP using maximum likelihood estimation of params
    gp.fit(X, y)
    # make predictions on meshed x-axis
    y_pred, MSE = gp.predict(x, eval_MSE=True)
    sigma = np.sqrt(MSE)

    # plot
    fig = plt.figure()
    plt.plot(x, f(x), 'r:', label=u'$f(x) = x\,\sin(x)$')
    plt.errorbar(X.ravel(),
                 y,
                 dy,
                 fmt='r.',
                 markersize=10,
                 label=u'Observations')
    plt.plot(x, y_pred, 'b-', label=u'Prediction')
    plt.fill(
        np.concatenate([x, x[::-1]]),  # reverse order of x
        np.concatenate(
            [y_pred - 1.9600 * sigma, (y_pred + 1.9600 * sigma)[::-1]]),
        alpha=0.5,
        fc='b',
        ec='None',
        label='95% confidence interval')
    # shade, fill color, edge color
    plt.title('Noisy case')
    plt.xlabel('$x$')
    plt.ylabel('$f(x)$')
    plt.ylim(-10, 20)
    plt.legend(loc='upper left')
    return
示例#52
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def next(grid, candidates, pending, complete, completed_values):
    gp = GaussianProcess(random_start=10, nugget=1e-6)
    gp.fit(_encode_categorical_df(complete, grid), completed_values)
    if pending.shape[0]:
        # Generate fantasies for pending
        mean, variance = gp.predict(_encode_categorical_df(pending, grid),
                                    eval_MSE=True)
        pending_value_estimation = pd.Series(mean + np.sqrt(variance) *
                                             npr.randn(mean.shape[0]))
        gp.fit(_encode_categorical_df(complete.append(pending), grid),
               completed_values.append(pending_value_estimation))

    # Predict the marginal means and variances at candidates.
    mean, variance = gp.predict(_encode_categorical_df(candidates, grid),
                                eval_MSE=True)
    best = np.min(completed_values)

    func_s = np.sqrt(variance) + 0.0001
    Z = (best - mean) / func_s
    ncdf = sps.norm.cdf(Z)
    npdf = sps.norm.pdf(Z)
    ei = func_s * (Z * ncdf + npdf)

    best_cand = np.argmax(ei)
    return (best_cand, grid)
示例#53
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def test_mse_solving():
    # test the MSE estimate to be sane.
    # non-regression test for ignoring off-diagonals of feature covariance,
    # testing with nugget that renders covariance useless, only
    # using the mean function, with low effective rank of data
    gp = GaussianProcess(corr='absolute_exponential', theta0=1e-4,
                         thetaL=1e-12, thetaU=1e-2, nugget=1e-2,
                         optimizer='Welch', regr="linear", random_state=0)

    X, y = make_regression(n_informative=3, n_features=60, noise=50,
                           random_state=0, effective_rank=1)

    gp.fit(X, y)
    assert_greater(1000, gp.predict(X, eval_MSE=True)[1].mean())
示例#54
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class COGP(object):

    def __init__(self, func, initial, minimize=True, storeAllEvaluations=True,
                 storeAllEvaluated=True, maxEvaluations=10):
        self.func = func
        self.X = np.array(initial)
        self.y = np.array([func(el) for el in initial])
        LEFT = np.min(initial)
        RIGHT = np.max(initial)
        self.x = [i for i in itertools.product(np.arange(LEFT, RIGHT, 0.1),
                                               repeat=len(initial[0]))]
        self.fmin = np.min(self.y)
        self.argmin = self.X[np.argmin(self.y)]
        self.gp = GaussianProcess(corr='cubic', theta0=1e-2, thetaL=1e-4,
                                  thetaU=1e-1)
        self.storeAllEvaluations = storeAllEvaluations
        self.storeAllEvaluated = storeAllEvaluated
        if storeAllEvaluations:
            self._allEvaluations = []
        if storeAllEvaluated:
            self._allEvaluated = []
        self.max_evaluations = maxEvaluations
        self.time = 0

    def learn(self):
        wall_time = time.time()
        for step in xrange(self.max_evaluations):
            try:
                self.gp.fit(self.X, self.y)
            except:
                break
            y_pred, MSE = self.gp.predict(self.x, eval_MSE=True)

            s = (self.fmin-y_pred) / np.sqrt(MSE)
            argm = np.argmax(MSE * (s * norm.cdf(s) + norm.pdf(s)))

            self.X = np.vstack([self.X, self.x[argm]])
            f = self.func(self.x[argm])
            if self.storeAllEvaluations:
                self._allEvaluations.append(f)
            if self.storeAllEvaluated:
                self._allEvaluated.append(self.x[argm])
            self.y = np.hstack([self.y, f])
            if f < self.fmin:
                self.fmin = f
                self.argmin = self.x[argm]

        self.time = time.time() - wall_time
        return (np.array(self.argmin), self.fmin)
def decompose_model(timeseries, fcst_window):
    composed_df = pd.DataFrame()
    res_df = pd.DataFrame()
    res_test = sm.seasonal_decompose(timeseries.dropna(),
                                     two_sided=False)
    composed_df['trend'] = res_test.trend.dropna()
    composed_df['seasonal'] = res_test.seasonal.dropna()
    composed_df['residual'] = res_test.resid.dropna()

    # create date index for the output data frame
    date_rng = pd.date_range(composed_df.index[len(composed_df) - 1] + DateOffset(months=1),
                             periods=fcst_window,
                             freq='MS')
    res_df['Date'] = pd.to_datetime(date_rng,
                                    errors='coerce')
    res_df = res_df.sort_values(by='Date')
    res_df = res_df.set_index('Date')

    # predict the residual component
    resid_mean = composed_df['residual'].mean()
    res_df['Residual'] = resid_mean

    # predict the seasonal component
    last_year = date_rng[0].year - 1
    last_year_rng = pd.date_range(date(last_year, 1, 1),
                                  periods=12,
                                  freq='MS')
    seas_data = composed_df.loc[composed_df.index.isin(last_year_rng)].seasonal
    seas_val = list()
    for i in range(fcst_window):
        seas_val.append(seas_data[res_df.index[i].month - 1])

    res_df['Seasonal'] = seas_val

    # predict the trend component (Gaussian Process)
    x_fit = (composed_df.index - composed_df.index[0]).days.tolist()
    x_test = (res_df.index - composed_df.index[0]).days.tolist()
    x_fit_np = np.asarray(x_fit).reshape((-1, 1))
    x_test_np = np.asarray(x_test).reshape((-1, 1))
    y_fit = composed_df['trend'].values
    y_fit_np = np.asarray(y_fit).reshape((-1, 1))
    gpr = GaussianProcess(corr='cubic', regr='linear', theta0=1e-2, thetaL=1e-4, thetaU=1e-1,
                          random_start=100)
    gpr.fit(x_fit_np, y_fit_np)
    y_gpr = gpr.predict(x_test_np)
    res_df['Trend'] = y_gpr
    res_df['Total'] = res_df.sum(axis=1)
    res_df.loc[res_df['Total'] < 0, 'Total'] = 0
    return res_df
 def __init__(self,
              num_in_samples=2,
              sampling_function=uniform_random_sampling):
     self.gp = GaussianProcess(corr='squared_exponential',
                               theta0=1e-2,
                               thetaL=1e-4,
                               thetaU=1e-1,
                               random_start=100)
     self.results_hash = {}
     self.observations = []
     self.samples = []
     self.num_in_samples = num_in_samples
     self.sampling_function = sampling_function
     self.model_robot_results = {}
     self.generateX_AND_getY_for_training()
示例#57
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 def __init__(self,
              func,
              initial,
              minimize=True,
              storeAllEvaluations=True,
              storeAllEvaluated=True,
              maxEvaluations=10):
     self.func = func
     self.lst = initial
     self.gp = GaussianProcess(corr='cubic',
                               theta0=1e-2,
                               thetaL=1e-4,
                               thetaU=1e-1,
                               random_start=100)
     self.max_evaluations = maxEvaluations
def test_batch_size():
    # TypeError when using batch_size on Python 3, see
    # https://github.com/scikit-learn/scikit-learn/issues/7329 for more
    # details
    gp = GaussianProcess()
    gp.fit(X, y)
    gp.predict(X, batch_size=1)
    gp.predict(X, batch_size=1, eval_MSE=True)