Esempio n. 1
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    def _buildKrigingAlgo(self, inputSample, outputSample):
        """
        Build the functional chaos algorithm without running it.
        """
        if self._basis is None:
            # create linear basis only for the defect parameter (1st parameter),
            # constant otherwise
            input = ['x' + str(i) for i in range(self._dim)]
            functions = []
            # constant
            functions.append(ot.SymbolicFunction(input, ['1']))
            # linear for the first parameter only
            functions.append(ot.SymbolicFunction(input, [input[0]]))
            self._basis = ot.Basis(functions)

        if self._covarianceModel is None:
            # anisotropic squared exponential covariance model
            self._covarianceModel = ot.SquaredExponential([1] * self._dim)

        # normalization
        mean = inputSample.computeMean()
        try:
            stddev = inputSample.computeStandardDeviation()
        except AttributeError:
            stddev = inputSample.computeStandardDeviationPerComponent()
        linear = ot.SquareMatrix(self._dim)
        for j in range(self._dim):
            linear[j, j] = 1.0 / stddev[j] if abs(stddev[j]) > 1e-12 else 1.0
        zero = [0.0] * self._dim
        transformation = ot.LinearFunction(mean, zero, linear)

        algoKriging = ot.KrigingAlgorithm(transformation(inputSample),
                                          outputSample, self._covarianceModel,
                                          self._basis)
        return algoKriging, transformation
def test_two_outputs():
    f = ot.SymbolicFunction(['x'], ['x * sin(x)', 'x * cos(x)'])
    sampleX = [[1.0], [2.0], [3.0], [4.0], [5.0], [6.0], [7.0], [8.0]]
    sampleY = f(sampleX)
    basis = ot.Basis([
        ot.SymbolicFunction(['x'], ['x']),
        ot.SymbolicFunction(['x'], ['x^2'])
    ])
    covarianceModel = ot.SquaredExponential([1.0])
    covarianceModel.setActiveParameter([])
    covarianceModel = ot.TensorizedCovarianceModel([covarianceModel] * 2)
    algo = ot.KrigingAlgorithm(sampleX, sampleY, covarianceModel, basis)
    algo.run()
    result = algo.getResult()
    mm = result.getMetaModel()
    assert mm.getOutputDimension() == 2, "wrong output dim"
    ott.assert_almost_equal(mm(sampleX), sampleY)
    # Check the conditional covariance
    reference_covariance = ot.Matrix([[4.4527, 0.0, 8.34404, 0.0],
                                      [0.0, 2.8883, 0.0, 5.41246],
                                      [8.34404, 0.0, 15.7824, 0.0],
                                      [0.0, 5.41246, 0.0, 10.2375]])
    ott.assert_almost_equal(
        result([[9.5], [10.0]]).getCovariance() - reference_covariance,
        ot.Matrix(4, 4), 0.0, 2e-2)
def test_two_outputs():
    f = ot.SymbolicFunction(['x'], ['x * sin(x)', 'x * cos(x)'])
    sampleX = [[1.0], [2.0], [3.0], [4.0], [5.0], [6.0], [7.0], [8.0]]
    sampleY = f(sampleX)
    basis = ot.Basis([ot.SymbolicFunction(['x'], ['x']),
                      ot.SymbolicFunction(['x'], ['x^2'])])
    covarianceModel = ot.SquaredExponential([1.0])
    covarianceModel.setActiveParameter([])
    algo = ot.KrigingAlgorithm(sampleX, sampleY, covarianceModel, basis)
    algo.run()
    result = algo.getResult()
    mm = result.getMetaModel()
    assert mm.getOutputDimension() == 2, "wrong output dim"
    ott.assert_almost_equal(mm(sampleX), sampleY)
Esempio n. 4
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    def fit(self, X, y, **fit_params):
        """Fit Kriging regression model.

        Parameters
        ----------
        X : array-like, shape = (n_samples, n_features)
            Training data.
        y : array-like, shape = (n_samples, [n_output_dims])
            Target values.

        Returns
        -------
        self : returns an instance of self.

        """
        if len(X) == 0:
            raise ValueError(
                "Can not perform a kriging algorithm with empty sample")
        # check data type is accurate
        if (len(np.shape(X)) != 2):
            raise ValueError("X has incorrect shape.")
        input_dimension = len(X[1])
        if len(np.shape(
                y)) == 1:  # For sklearn.multioutput.MultiOutputRegressor
            y = np.expand_dims(y, axis=1)
        if len(np.shape(y)) != 2:
            raise ValueError("y has incorrect shape.")

        if type(self.kernel) is str:
            covarianceModel = eval('ot.' + self.kernel + "(" +
                                   str(input_dimension) + ")")
        else:
            covarianceModel = ot.CovarianceModel(self.kernel)
        if type(self.basis) is str:
            basisCollection = eval('ot.' + self.basis + "BasisFactory(" +
                                   str(input_dimension) + ").build()")
        else:
            basisCollection = ot.Basis(self.basis)
        ot.ResourceMap.SetAsString("KrigingAlgorithm-LinearAlgebra",
                                   str(self.linalg_meth).upper())
        algo = ot.KrigingAlgorithm(X, y, covarianceModel, basisCollection)
        if self.n_iter_opt:
            opt_algo = algo.getOptimizationAlgorithm()
            opt_algo.setMaximumIterationNumber(self.n_iter_opt)
            algo.setOptimizationAlgorithm(opt_algo)
        else:
            algo.setOptimizeParameters(False)
        algo.run()
        self.result_ = algo.getResult()
        return self
Esempio n. 5
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    def setBasis(self, basis):
        """
        Accessor to the kriging basis. 

        Parameters
        ----------
        basis : :py:class:`openturns.Basis`
            The basis used as trend in the kriging model.
        """
        try:
            ot.Basis(basis)
        except NotImplementedError:
            raise Exception('The given parameter is not a Basis.')
        self._basis = basis
Esempio n. 6
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    def set_mean(self, mean):
        '''
        This function constructs the mean function
        takes the following argument:
            -> mean_type
        '''

        if mean.mean_type == 'Linear':
            self.mean_function = ot.LinearBasisFactory(self.input_dim).build()
        elif mean.mean_type == 'Constant':
            self.mean_function = ot.ConstantBasisFactory(
                self.input_dim).build()
        elif mean.mean_type == 'Quadratic':
            self.mean_function = ot.QuadraticBasisFactory(
                self.input_dim).build()
        elif mean.mean_type == 'Zero':
            self.mean_function = ot.Basis()
        else:
            self.mean_function = "This library does not support the specified mean function"
Esempio n. 7
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    def _buildKrigingAlgo(self, inputSample, outputSample):
        """
        Build the functional chaos algorithm without running it.
        """
        if self._basis is None:
            # create linear basis only for the defect parameter (1st parameter),
            # constant otherwise
            input = ['x' + str(i) for i in range(self._dim)]
            functions = []
            # constant
            functions.append(ot.NumericalMathFunction(input, ['y'], ['1']))
            # linear for the first parameter only
            functions.append(ot.NumericalMathFunction(input, ['y'],
                                                      [input[0]]))
            self._basis = ot.Basis(functions)

        if self._covarianceModel is None:
            # anisotropic squared exponential covariance model
            covColl = ot.CovarianceModelCollection(self._dim)
            for i in range(self._dim):
                if LooseVersion(ot.__version__) == '1.6':
                    covColl[i] = ot.SquaredExponential(1, 1.)
                elif LooseVersion(ot.__version__) > '1.6':
                    covColl[i] = ot.SquaredExponential([1], [1.])
            self._covarianceModel = ot.ProductCovarianceModel(covColl)

        if LooseVersion(ot.__version__) == "1.9":
            algoKriging = ot.KrigingAlgorithm(inputSample, outputSample,
                                              self._covarianceModel,
                                              self._basis)
        else:
            algoKriging = ot.KrigingAlgorithm(inputSample, outputSample,
                                              self._basis,
                                              self._covarianceModel, True)
        algoKriging.run()
        return algoKriging
import openturns as ot
from openturns.viewer import View

f = ot.SymbolicFunction(['x'], ['x + x * sin(x)'])
inputSample = ot.Sample([[1.0], [3.0], [5.0], [6.0], [7.0], [8.0]])
outputSample = f(inputSample)

f1 = ot.SymbolicFunction(['x'], ['sin(x)'])
f2 = ot.SymbolicFunction(['x'], ['x'])
f3 = ot.SymbolicFunction(['x'], ['cos(x)'])
basis = ot.Basis([f1, f2, f3])
covarianceModel = ot.SquaredExponential([1.0])
covarianceModel.setActiveParameter([])
algo = ot.GeneralLinearModelAlgorithm(inputSample, outputSample,
                                      covarianceModel, basis)
algo.run()
result = algo.getResult()
metamodel = result.getMetaModel()

graph = f.draw(0.0, 10.0)
graph.add(metamodel.draw(0.0, 10.0))
graph.add(ot.Cloud(inputSample, outputSample))
graph.setColors(['blue', 'red', 'black'])
graph.setLegends(['model', 'meta model', 'sample'])
graph.setLegendPosition('topleft')
graph.setTitle('y(x)=x + x * sin(x)')
View(graph, figure_kw={'figsize': (8, 4)})
Esempio n. 9
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# Create a trend
fTrend = ot.SymbolicFunction(["t"], ["1+2*t+t^2"])
fTemp = ot.TrendTransform(fTrend, myGrid)

# Add the trend to the process and get a field
myYProcess = ot.CompositeProcess(fTemp, myXProcess)
myYField = myYProcess.getRealization()

# Create a TrendFactory
myBasisSequenceFactory = ot.LARS()
myFittingAlgorithm = ot.KFold()
func1 = ot.SymbolicFunction(["t"], ["1"])
func2 = ot.SymbolicFunction(["t"], ["t"])
func3 = ot.SymbolicFunction(["t"], ["t^2"])
myBasis = ot.Basis([func1, func2, func3])

myTrendFactory = ot.TrendFactory(myBasisSequenceFactory, myFittingAlgorithm)

# Estimate the trend
myTrendTransform = myTrendFactory.build(myYField, myBasis)

graph = myTrendTransform.getTrendFunction().draw(0.0, 10.0)
graph.add(fTrend.draw(0.0, 10.0))
graph.add(ot.Cloud(myYField.getMesh().getVertices(), myYField.getValues()))
graph.setColors(['red', 'blue', 'black'])
graph.setLegends(['estimated trend', 'real trend', 'sample'])
graph.setLegendPosition('topleft')
graph.setYTitle('values')
graph.setTitle("Trend estimation from a field")
polyColl = [univariateFactory]*dimension

# %%
enumerateFunction = ot.LinearEnumerateFunction(dimension)
productBasis = ot.OrthogonalProductPolynomialFactory(polyColl, enumerateFunction)

# %%
functions = []
numberOfTrendCoefficients = 12
for i in range(numberOfTrendCoefficients):
    multivariatepolynomial = productBasis.build(i)
    print(multivariatepolynomial)
    functions.append(multivariatepolynomial)

# %%
basis = ot.Basis(functions)

# %%
# Create the metamodel
# --------------------

# %%
# In order to create the kriging metamodel, we first select a constant trend with the `ConstantBasisFactory` class. Then we use a squared exponential covariance model. Finally, we use the `KrigingAlgorithm` class to create the kriging metamodel, taking the training sample, the covariance model and the trend basis as input arguments. 

# %%
covarianceModel = ot.SquaredExponential([1.]*dimension, [1.0])

# %%
algo = ot.KrigingAlgorithm(X_train, Y_train, covarianceModel, basis)
algo.run()
result = algo.getResult()
class pyf2p(ot.OpenTURNSPythonFieldToPointFunction):
    def __init__(self, mesh):
        super(pyf2p, self).__init__(mesh, in_dim, out_dim)
        self.setInputDescription(["x1", "x2", "x3", "x4"])
        self.setOutputDescription(['g'])
    def _exec(self, X):
        Xs = ot.Sample(X)
        x1, x2, x3, x4 = Xs.computeMean()
        y = x1 + x2 + x3 - x4 + x1 * x2 - x3 * x4 - 0.1 * x1 * x2 * x3
        return [y]
f = ot.FieldToPointFunction(pyf2p(tg))

# First process: elementary process based on a bivariate random vector
f1 = ot.SymbolicFunction(['t'], ['sin(t)'])
f2 = ot.SymbolicFunction(['t'], ['cos(t)^2'])
myBasis = ot.Basis([f1, f2])
coefDis = ot.Normal([1.0] * 2, [0.6] * 2, ot.CorrelationMatrix(2))
p1 = ot.FunctionalBasisProcess(coefDis, myBasis, tg)

# Second process: smooth Gaussian process
p2 = ot.GaussianProcess(ot.SquaredExponential([1.0], [T / 4.0]), tg)

# Third process: elementary process based on a bivariate random vector
randomParameters = ot.ComposedDistribution([ot.Uniform(), ot.Normal()])
p3 = ot.FunctionalBasisProcess(randomParameters, ot.Basis([ot.SymbolicFunction(["t"], ["1", "0"]), ot.SymbolicFunction(["t"], ["0", "1"])]))

X = ot.AggregatedProcess([p1, p2, p3])
X.setMesh(tg)

N = 1000
x = X.getSample(N)
ftest = summary[9][0]

# openturns like
X = ot.Sample(len(pop15), 0)
P = ot.Sample.BuildFromPoint(pop15)
X.stack(P)
P = ot.Sample.BuildFromPoint(pop75)
X.stack(P)
X.setDescription(["pop15", "pop75"])
Y = ot.Sample.BuildFromPoint(sr)
# Model with pop15 + pop75 without intercept
# We do not run mode with pop15 only for the moment
f = ot.SymbolicFunction(["pop15", "pop75"], ["pop15"])
g = ot.SymbolicFunction(["pop15", "pop75"], ["pop75"])
h = ot.SymbolicFunction(["pop15", "pop75"], ["1"])
basis = ot.Basis([f, g])
model = ot.LinearModelAlgorithm(X, basis, Y)
model.run()
result = model.getResult()
analysis = ot.LinearModelAnalysis(result)

np.testing.assert_almost_equal(result.getRSquared(), r2, 14)
np.testing.assert_almost_equal(result.getAdjustedRSquared(), ar2, 14)
np.testing.assert_almost_equal(analysis.getFisherScore(), ftest, 14)

#---------------------------------------------------------------------
# Model 2 : 2 param + intercepts

formula = Formula('sr ~ pop75 + pop15')
fit = stats.lm(formula)
summary = stats.summary_lm(fit)
Esempio n. 13
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#! /usr/bin/env python

from __future__ import print_function
import openturns as ot
from math import *

ot.TESTPREAMBLE()

try:

    basis = ot.Basis()
    print('basis =', basis)
    basisSize = 3

    phis = []
    for j in range(basisSize):
        phis.append(ot.SymbolicFunction(['x'], ['x^' + str(j + 1)]))
    basis = ot.Basis(phis)
    print('basis =', basis)

    print(basis.getSize())
    print(basis.getSubBasis([1, 2]))
    print(basis.isFinite())
    print(basis.isOrthogonal())
    # print(basis[1])
    # print(basis[0:2])

    # basis[1] = ot.Function(['x'], ['z'], ['x^42'])
    # print('basis =', basis)
    # basis[0:2] = basis[1:3]
    # print('basis =', basis)
        self.setInputDescription(["x1", "x2", "x3", "x4"])
        self.setOutputDescription(['g'])

    def _exec(self, X):
        Xs = ot.Sample(X)
        x1, x2, x3, x4 = Xs.computeMean()
        y = x1 + x2 + x3 - x4 + x1 * x2 - x3 * x4 - 0.1 * x1 * x2 * x3
        return [y]


f = ot.FieldToPointFunction(pyf2p(tg))

# First process: elementary process based on a bivariate random vector
f1 = ot.SymbolicFunction(['t'], ['sin(t)'])
f2 = ot.SymbolicFunction(['t'], ['cos(t)^2'])
myBasis = ot.Basis([f1, f2])
coefDis = ot.Normal([1.0] * 2, [0.6] * 2, ot.CorrelationMatrix(2))
p1 = ot.FunctionalBasisProcess(coefDis, myBasis, tg)

# Second process: smooth Gaussian process
p2 = ot.GaussianProcess(ot.SquaredExponential([1.0], [T / 4.0]), tg)

# Third process: elementary process based on a bivariate random vector
randomParameters = ot.ComposedDistribution([ot.Uniform(), ot.Normal()])
p3 = ot.FunctionalBasisProcess(
    randomParameters,
    ot.Basis([
        ot.SymbolicFunction(["t"], ["1", "0"]),
        ot.SymbolicFunction(["t"], ["0", "1"])
    ]))
Esempio n. 15
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enumerateFunction = ot.EnumerateFunction(dim)
factory = ot.OrthogonalProductPolynomialFactory([ot.MonomialFactory()]*dim, enumerateFunction)

# Build 'interactions' as a list of list [a1,a2,a3,a4,a5], and we will generate tensorized
# polynomials SAL^a1*pH^a2*K^a3*Na^a4*Zn^a5.

# BIO~SAL+pH+K+Na+Zn
interactions = []
interactions.append([0]*dim)
for i in xrange(dim):
  indices = [0]*dim
  indices[i] = 1
  # Y ~ I(Xi)^1
  interactions.append(indices[:])

basis = ot.Basis([factory.build(enumerateFunction.inverse(indices)) for indices in interactions])
################################################################################################

i_min = [interactions.index([0,0,0,0,0])]
i_0 = i_min[:]

#---------------- Forward / Backward------------------- 
#   X: input sample
#   basis : Basis
#   Y: output sample
#   i_min:  indices of minimal model
#   direction: Boolean (True FORWARD, False BACKWARD)
#   penalty: multiplier of number of degrees of freedom
#   maxiteration: maximum number of iterations

#---------------- Both------------------- 
Esempio n. 16
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#! /usr/bin/env python

from __future__ import print_function
import openturns as ot

R = ot.CorrelationMatrix(2)
R[0, 1] = -0.99
d1 = ot.Normal([-1.0, 1.0], [1.0, 1.0], R)
R[0, 1] = 0.99
d2 = ot.Normal([1.0, 1.0], [1.0, 1.0], R)
distribution = ot.Mixture([d1, d2], [1.0] * 2)
classifier = ot.MixtureClassifier(distribution)
f1 = ot.SymbolicFunction(['x'], ['-x'])
f2 = ot.SymbolicFunction(['x'], ['x'])
experts = ot.Basis([f1, f2])
moe = ot.ExpertMixture(experts, classifier)
moeNMF = ot.Function(moe)

print('Mixture of experts=', moe)

# Evaluate the mixture of experts on some points
for i in range(2):
    p = [-0.3 + 0.8 * i / 4.0]
    print('moe   ( %.6g )=' % p[0], moe(p))
    print('moeNMF( %.6g )=' % p[0], moeNMF(p))
# and on a sample
x = [[-0.3], [0.1]]
print('x=', ot.Sample(x), 'moeNMF(x)=', moeNMF(x))

# non-supervised mode (2d)
f1 = ot.SymbolicFunction(['x1', 'x2'], ['-8'])
Esempio n. 17
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graph = mm2.draw(1e-6, 1.0)
view = viewer.View(graph)

# %%
# Define the mixture
R = ot.CorrelationMatrix(2)
d1 = ot.Normal([-1.0, -1.0], [1.0] * 2, R)  # segment 1
d2 = ot.Normal([1.0, 1.0], [1.0] * 2, R)  # segment 2
weights = [1.0] * 2
atoms = [d1, d2]
mixture = ot.Mixture(atoms, weights)

# %%
# Create the classifier based on the mixture
classifier = ot.MixtureClassifier(mixture)

# %%
# Create local experts using the metamodels
experts = ot.Basis([mm1, mm2])

# %%
# Create a mixture of experts
evaluation = ot.ExpertMixture(experts, classifier)
moe = ot.Function(evaluation)

# %%
# Draw the mixture of experts
graph = moe.draw(-1.0, 1.0)
view = viewer.View(graph)
plt.show()
Esempio n. 18
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import openturns as ot
from openturns.viewer import View

f = ot.SymbolicFunction(['x'],  ['x * sin(x)'])
sampleX = [[1.0], [2.0], [3.0], [4.0], [5.0], [6.0], [7.0], [8.0]]
sampleY = f(sampleX)
basis = ot.Basis([ot.SymbolicFunction(['x'], ['x']),
                  ot.SymbolicFunction(['x'], ['x^2'])])
covarianceModel = ot.SquaredExponential([1.0])
covarianceModel.setActiveParameter([])
algo = ot.KrigingAlgorithm(sampleX, sampleY, covarianceModel, basis)
algo.run()
result = algo.getResult()

graph = f.draw(0.0, 10.0)
graph.add(result.getMetaModel().draw(0.0, 10.0))
graph.add(ot.Cloud(sampleX, sampleY))
graph.setColors(['blue', 'red', 'black'])
graph.setLegends(['model', 'meta model', 'sample'])
graph.setLegendPosition('topleft')
graph.setTitle('y(x)=x * sin(x)')
View(graph, figure_kwargs={'figsize': (8, 4)})
Esempio n. 19
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#! /usr/bin/env python

from __future__ import print_function
import openturns as ot

basisSize = 3
sampleSize = 3

X = ot.NumericalSample(sampleSize, 1)
for i in range(sampleSize):
    X[i, 0] = i + 1.0

Y = ot.NumericalSample(sampleSize, 1)

phis = []
for j in range(basisSize):
    phis.append(ot.NumericalMathFunction(['x'], ['y'], ['x^' + str(j + 1)]))
basis = ot.Basis(phis)
for i in range(basisSize):
    print(ot.NumericalMathFunctionCollection(basis)[i](X))

proxy = ot.DesignProxy(X, basis)
full = range(basisSize)

design = proxy.computeDesign(full)
print(design)

proxy.setWeight([0.5] * sampleSize)
design = proxy.computeDesign(full)
print(design)
from matplotlib import pylab as plt
import math as m
ot.Log.Show(ot.Log.NONE)

# %%
# Define the coefficients distribution
mu = [2.0]*2
sigma = [5.0]*2
R = ot.CorrelationMatrix(2)
coefDist = ot.Normal(mu, sigma, R)

# %%
# Create a basis of functions
phi_1 = ot.SymbolicFunction(['t'], ['sin(t)'])
phi_2 = ot.SymbolicFunction(['t'], ['cos(t)^2'])
myBasis = ot.Basis([phi_1, phi_2])

# %%
# Create the mesh
myMesh = ot.RegularGrid(0.0, 0.1, 100)

# %%
# Create the process
process = ot.FunctionalBasisProcess(coefDist, myBasis, myMesh)

# %%
# Draw a sample
N = 6
sample = process.getSample(N)
graph = sample.drawMarginal(0)
graph.setTitle(str(N)+' realizations of functional basis process')
Esempio n. 21
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interactions.append([0] * dim)
for i in range(dim):
    indices = [0] * dim
    indices[i] = 1
    # Y ~ I(Xi)^1
    interactions.append(indices[:])

funcs = [
    factory.build(enumerateFunction.inverse(indices))
    for indices in interactions
]
description = X.getDescription()
description.add('f')
[f.setDescription(description) for f in funcs]

basis = ot.Basis(funcs)
#

i_min = [interactions.index([0, 0, 0, 0, 0])]
i_0 = i_min[:]

penalty_BIC = log(X.getSize())
penalty_AIC = 2.
maxiteration = 1000

for k in [penalty_AIC, penalty_BIC]:
    # Forward / Backward
    if k == penalty_AIC:
        IC = " AIC "
    if k == penalty_BIC:
        IC = " BIC "
Esempio n. 22
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import openturns as ot
from math import exp
from matplotlib import pyplot as plt
from openturns.viewer import View

f1 = ot.SymbolicFunction(['t'], ['sin(t)'])
f2 = ot.SymbolicFunction(['t'], ['cos(t)*cos(t)'])
myBasis = ot.Basis([f1, f2])
coefDis = ot.Normal([2] * 2, [5] * 2, ot.CorrelationMatrix(2))
myTG = ot.RegularGrid(0.0, 0.1, 250)

myFBP = ot.FunctionalBasisProcess(coefDis, myBasis, myTG)

TS = myFBP.getRealization()

graph = TS.draw()
graph.add(myFBP.getRealization().draw())
graph.add(myFBP.getRealization().draw())
graph.setColors(['red', 'blue', 'green'])

fig = plt.figure(figsize=(10, 4))
plt.suptitle('Functional Basis Process')
fbp_axis = fig.add_subplot(111)
view = View(graph, figure=fig, axes=[fbp_axis], add_legend=False)
# Define the fitting algorithm using the
# Corrected Leave One Out or KFold algorithms
myFittingAlgorithm = ot.CorrectedLeaveOneOut()
myFittingAlgorithm_2 = ot.KFold()

# Define the basis function
# For example composed of 5 functions
myFunctionBasis = list(map(lambda fst: ot.SymbolicFunction(
    ['t', 's'], [fst]), ['1', 't', 's', 't^2', 's^2']))

# Define the trend function factory algorithm
myTrendFactory = ot.TrendFactory(myBasisSequenceFactory, myFittingAlgorithm)

# Create the trend transformation  of type TrendTransform
myTrendTransform = myTrendFactory.build(myYField, ot.Basis(myFunctionBasis))

# Check the estimated trend function
print('Trend function = ', myTrendTransform)

# %%
# CASE 2 : we impose the trend (or its inverse)

# The function g computes the trend : R^2 -> R
# g :      R^2 --> R
#          (t,s) --> 1+2t+2s
g = ot.SymbolicFunction(['t', 's'], ['1+2*t+2*s'])
gTemp = ot.TrendTransform(g, myMesh)

# Get the inverse trend transformation
# from the trend transform already defined
Esempio n. 24
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#

# %%
import openturns as ot
from openturns.viewer import View

# %%
# First build a process to generate the input data.
# We assemble a 4-d process from functional and Gaussian processes.
T = 3.0
NT = 32
tg = ot.RegularGrid(0.0, T / NT, NT)
f1 = ot.SymbolicFunction(['t'], ['sin(t)'])
f2 = ot.SymbolicFunction(['t'], ['cos(t)^2'])
coeff1_dist = ot.Normal([1.0] * 2, [0.6] * 2, ot.CorrelationMatrix(2))
p1 = ot.FunctionalBasisProcess(coeff1_dist, ot.Basis([f1, f2]), tg)
p2 = ot.GaussianProcess(ot.SquaredExponential([1.0], [T / 4.0]), tg)
coeff3_dist = ot.ComposedDistribution([ot.Uniform(), ot.Normal()])
f1 = ot.SymbolicFunction(["t"], ["1", "0"])
f2 = ot.SymbolicFunction(["t"], ["0", "1"])
p3 = ot.FunctionalBasisProcess(coeff3_dist, ot.Basis([f1, f2]))
X = ot.AggregatedProcess([p1, p2, p3])
X.setMesh(tg)

# %%
# Draw some input trajectories from our process
ot.RandomGenerator.SetSeed(0)
x = X.getSample(10)
graph = x.drawMarginal(0)
graph.setTitle(f'{x.getSize()} input trajectories')
_ = View(graph)