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Comparing sensitivity indices#
from __future__ import annotations
from gemseo import configure_logger
from gemseo.problems.uncertainty.ishigami.ishigami_discipline import IshigamiDiscipline
from gemseo.problems.uncertainty.ishigami.ishigami_space import IshigamiSpace
from gemseo.uncertainty.sensitivity.correlation_analysis import CorrelationAnalysis
from gemseo.uncertainty.sensitivity.morris_analysis import MorrisAnalysis
configure_logger()
<RootLogger root (INFO)>
In this example, we consider the Ishigami function [IH90]
implemented as an Discipline
by the IshigamiDiscipline
.
It is commonly used
with the independent random variables \(X_1\), \(X_2\) and \(X_3\)
uniformly distributed between \(-\pi\) and \(\pi\)
and defined in the IshigamiSpace
.
discipline = IshigamiDiscipline()
uncertain_space = IshigamiSpace()
We would like to carry out two sensitivity analyses, e.g. a first one based on correlation coefficients and a second one based on the Morris methodology, and compare the results,
Firstly,
we create a CorrelationAnalysis
and compute the sensitivity indices:
correlation = CorrelationAnalysis()
correlation.compute_samples([discipline], uncertain_space, 10)
correlation.compute_indices()
WARNING - 00:12:16: No coupling in MDA, switching chain_linearize to True.
INFO - 00:12:16: *** Start CorrelationAnalysisSamplingPhase execution ***
INFO - 00:12:16: CorrelationAnalysisSamplingPhase
INFO - 00:12:16: Disciplines: IshigamiDiscipline
INFO - 00:12:16: MDO formulation: MDF
INFO - 00:12:16: Running the algorithm OT_MONTE_CARLO:
INFO - 00:12:16: 10%|█ | 1/10 [00:00<00:00, 417.22 it/sec]
INFO - 00:12:16: 20%|██ | 2/10 [00:00<00:00, 678.91 it/sec]
INFO - 00:12:16: 30%|███ | 3/10 [00:00<00:00, 888.87 it/sec]
INFO - 00:12:16: 40%|████ | 4/10 [00:00<00:00, 1048.77 it/sec]
INFO - 00:12:16: 50%|█████ | 5/10 [00:00<00:00, 1187.58 it/sec]
INFO - 00:12:16: 60%|██████ | 6/10 [00:00<00:00, 1304.54 it/sec]
INFO - 00:12:16: 70%|███████ | 7/10 [00:00<00:00, 1397.90 it/sec]
INFO - 00:12:16: 80%|████████ | 8/10 [00:00<00:00, 1483.86 it/sec]
INFO - 00:12:16: 90%|█████████ | 9/10 [00:00<00:00, 1553.83 it/sec]
INFO - 00:12:16: 100%|██████████| 10/10 [00:00<00:00, 1621.68 it/sec]
INFO - 00:12:16: *** End CorrelationAnalysisSamplingPhase execution (time: 0:00:00.011180) ***
CorrelationAnalysis.SensitivityIndices(kendall={'y': [{'x1': array([0.55555556]), 'x2': array([0.02222222]), 'x3': array([-0.11111111])}]}, pcc={'y': [{'x1': array([0.84696461]), 'x2': array([0.68814608]), 'x3': array([-0.29846394])}]}, pearson={'y': [{'x1': array([0.685388]), 'x2': array([0.09681897]), 'x3': array([-0.23027298])}]}, prcc={'y': [{'x1': array([0.90374102]), 'x2': array([0.76539572]), 'x3': array([-0.02232206])}]}, spearman={'y': [{'x1': array([0.74545455]), 'x2': array([0.04242424]), 'x3': array([-0.09090909])}]}, src={'y': [{'x1': array([0.94001308]), 'x2': array([0.55748872]), 'x3': array([-0.16157012])}]}, srrc={'y': [{'x1': array([1.06252802]), 'x2': array([0.60167726]), 'x3': array([-0.00959941])}]}, ssrc={'y': [{'x1': array([0.88362459]), 'x2': array([0.31079367]), 'x3': array([0.0261049])}]})
Then,
we create an MorrisAnalysis
and compute the sensitivity indices:
morris = MorrisAnalysis()
morris.compute_samples([discipline], uncertain_space, 10)
morris.compute_indices()
WARNING - 00:12:16: No coupling in MDA, switching chain_linearize to True.
INFO - 00:12:16: *** Start MorrisAnalysisSamplingPhase execution ***
INFO - 00:12:16: MorrisAnalysisSamplingPhase
INFO - 00:12:16: Disciplines: IshigamiDiscipline
INFO - 00:12:16: MDO formulation: MDF
INFO - 00:12:16: Running the algorithm MorrisDOE:
INFO - 00:12:16: 12%|█▎ | 1/8 [00:00<00:00, 2880.70 it/sec]
INFO - 00:12:16: 25%|██▌ | 2/8 [00:00<00:00, 2581.90 it/sec]
INFO - 00:12:16: 38%|███▊ | 3/8 [00:00<00:00, 2379.52 it/sec]
INFO - 00:12:16: 50%|█████ | 4/8 [00:00<00:00, 2347.12 it/sec]
INFO - 00:12:16: 62%|██████▎ | 5/8 [00:00<00:00, 2355.56 it/sec]
INFO - 00:12:16: 75%|███████▌ | 6/8 [00:00<00:00, 2389.24 it/sec]
INFO - 00:12:16: 88%|████████▊ | 7/8 [00:00<00:00, 2381.00 it/sec]
INFO - 00:12:16: 100%|██████████| 8/8 [00:00<00:00, 2379.58 it/sec]
INFO - 00:12:16: *** End MorrisAnalysisSamplingPhase execution (time: 0:00:00.008583) ***
MorrisAnalysis.SensitivityIndices(mu={'y': [{'x1': array([0.73532408]), 'x2': array([-0.05115399]), 'x3': array([-1.6024484])}]}, mu_star={'y': [{'x1': array([0.76770333]), 'x2': array([2.09435091]), 'x3': array([1.6024484])}]}, sigma={'y': [{'x1': array([0.76770333]), 'x2': array([2.09435091]), 'x3': array([1.58984353])}]}, relative_sigma={'y': [{'x1': array([1.]), 'x2': array([1.]), 'x3': array([0.99213399])}]}, min={'y': [{'x1': array([0.03237925]), 'x2': array([2.04319692]), 'x3': array([0.01260487])}]}, max={'y': [{'x1': array([1.50302741]), 'x2': array([2.14550491]), 'x3': array([3.19229192])}]})
Lastly,
we compare these analyses
with the graphical method BaseSensitivityAnalysis.plot_comparison()
,
either using a bar chart:
morris.plot_comparison(correlation, "y", use_bar_plot=True, save=False, show=True)

<gemseo.post.dataset.bars.BarPlot object at 0x74788407b590>
or a radar plot:
morris.plot_comparison(correlation, "y", use_bar_plot=False, save=False, show=True)

<gemseo.post.dataset.radar_chart.RadarChart object at 0x747880fc4c80>
Total running time of the script: (0 minutes 0.304 seconds)