示例#1
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# Graphical copula validation
# ---------------------------
#
# In this paragraph we visualize an estimated copula versus the data in the rank space.
#

# %%
# First we create data
marginals = [ot.Normal()] * 2
dist = ot.ComposedDistribution(marginals, ot.ClaytonCopula(3))
N = 500
sample = dist.getSample(N)

# %%
# We build a estimate copula from the previous sample using the :class:`~openturns.ClaytonCopulaFactory` :
estimated = ot.ClaytonCopulaFactory().build(sample)

# %%
# We represent data as a cloud in the rank space :
ranksTransf = ot.MarginalTransformationEvaluation(
    marginals, ot.MarginalTransformationEvaluation.FROM)
rankSample = ranksTransf(sample)
rankCloud = ot.Cloud(rankSample, 'blue', 'plus', 'sample')

# %%
# We can plot the graph with rank sample and estimated copula :
myGraph = ot.Graph('Parametric estimation of the copula', 'X', 'Y', True,
                   'topleft')
myGraph.setLegendPosition('bottomright')
myGraph.add(rankCloud)
示例#2
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import openturns as ot
from matplotlib import pyplot as plt
from openturns.viewer import View
ot.RandomGenerator.SetSeed(0)
factory = ot.ClaytonCopulaFactory()
ref = factory.build()
dimension = ref.getDimension()
if dimension <= 2:
    sample = ref.getSample(50)
    distribution = factory.build(sample)
    if dimension == 1:
        distribution.setDescription(['$t$'])
        pdf_graph = distribution.drawPDF(256)
        cloud = ot.Cloud(sample, ot.Sample(sample.getSize(), 1))
        cloud.setColor('blue')
        cloud.setPointStyle('fcircle')
        pdf_graph.add(cloud)
        fig = plt.figure(figsize=(10, 4))
        plt.suptitle(str(distribution))
        pdf_axis = fig.add_subplot(111)
        View(pdf_graph, figure=fig, axes=[pdf_axis], add_legend=False)
    else:
        sample = ref.getSample(500)
        distribution.setDescription(['$t_0$', '$t_1$'])
        pdf_graph = distribution.drawPDF([256] * 2)
        cloud = ot.Cloud(sample)
        cloud.setColor('red')
        cloud.setPointStyle('fcircle')
        pdf_graph.add(cloud)
        fig = plt.figure(figsize=(10, 4))
        plt.suptitle(str(distribution))