Example 2: Morris use-case and LHS initial design

To define the trajectories, we first get an LHS design in the box of size We set the number of trajectories input variables are randomly to 10.

import openturns as ot
import otmorris
import openturns.viewer as otv

use the reference 20-d function from the Morris paper

f = ot.Function(otmorris.MorrisFunction())
dim = f.getInputDimension()

Number of trajectories

r = 10

Define an LHS experiment of size 50 in [0, 1]^20

size = 50
dist = ot.ComposedDistribution([ot.Uniform(0, 1)] * dim)
lhs_experiment = ot.LHSExperiment(dist, size, True, False)
lhsDesign = lhs_experiment.generate()
morris_experiment = otmorris.MorrisExperimentLHS(lhsDesign, r)
bounds = ot.Interval(dim)  # [0, 1]^20
X = morris_experiment.generate()
Y = f(X)

Evaluate Elementary effects (ee)

morris = otmorris.Morris(X, Y, bounds)

Compute mu/sigma

mean = morris.getMeanAbsoluteElementaryEffects()
sigma = morris.getStandardDeviationElementaryEffects()
graph = morris.drawElementaryEffects(0)
graph.setTitle("Elementary Effects using LHS")
view = otv.View(graph)

otv.View.ShowAll()