Create a composed function

In this example we are going to create a composed function

from __future__ import print_function
import openturns as ot
import openturns.viewer as viewer
from matplotlib import pylab as plt
import math as m
ot.Log.Show(ot.Log.NONE)

assume f, g functions

g = ot.SymbolicFunction(['x1', 'x2'],
                        ['x1 + x2', '3 * x1 * x2'])
f = ot.SymbolicFunction(['x1', 'x2'], ['2 * x1 - x2'])

create the composed function

function = ot.ComposedFunction(f, g)

evaluate the function

x = [3.0, 4.0]
y = function(x)
print('x=', x, 'y=', y)

Out:

x= [3.0, 4.0] y= [-22]