Create a parametric function

In this example we are going to create a parametric function:

d_{L,I}(E, F):  \mathbb{R}^2  \rightarrow \mathbb{R}

function from an existing “full” function:

d(E, F, L, I):  \mathbb{R}^4  \rightarrow \mathbb{R}

import openturns as ot

ot.Log.Show(ot.Log.NONE)

Create the function with all parameters d(E, F, L, I)

def d_func(X):
    E, F, L, II = X
    d = -F * L**3 / (3.0 * E * II)
    return [d]


beam = ot.PythonFunction(4, 1, d_func)

Evaluate d

x = [50.0, 1.0, 10.0, 5.0]
beam(x)
class=Point name=Unnamed dimension=1 values=[-1.33333]


Create the indices of the frozen parameters (L,I) from the full parameter list

indices = [2, 3]

Create the values of the frozen parameters (L,I)

referencePoint = [10.0, 5.0]

Create the parametric function

beam_LI = ot.ParametricFunction(beam, indices, referencePoint)

Evaluate d on (E,F) with fixed parameters (L,I)

beam_LI([50.0, 1.0])
class=Point name=Unnamed dimension=1 values=[-1.33333]