Running a script

To get started with BornAgain scripting, run a first example.

We assume that BornAgain and Python are installed and that the Python interpreter can import bornagain (see preceding page, “Check Installation”).

We shall now run a first example script. This and all other example scripts can also be found in the BornAgain distribution, in directory auto/Examples.

Download the following example script, using the link just below the code frame. Save the script under the name AlternatingLayers1.py.

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#!/usr/bin/env python3
"""
Basic example of specular reflectometry simulation.
The sample consists of 20 alternating Ti and Ni layers.
"""
import bornagain as ba
from bornagain import ba_plot as bp, deg, angstrom
import matplotlib.pyplot as plt


def get_sample():
    # Materials
    vacuum = ba.MaterialBySLD("Vacuum", 0, 0)
    material_Ti = ba.MaterialBySLD("Ti", -1.9493e-06, 0)
    material_Ni = ba.MaterialBySLD("Ni", 9.4245e-06, 0)
    material_Si = ba.MaterialBySLD("Si", 2.0704e-06, 0)

    # Layers
    top_layer = ba.Layer(vacuum)
    ti_layer = ba.Layer(material_Ti, 30*angstrom)
    ni_layer = ba.Layer(material_Ni, 70*angstrom)
    substrate = ba.Layer(material_Si)

    # Sample
    sample = ba.Sample()
    sample.addLayer(top_layer)
    for _ in range(10):
        sample.addLayer(ti_layer)
        sample.addLayer(ni_layer)
    sample.addLayer(substrate)

    return sample


def get_simulation(sample):
    n = 500
    scan = ba.AlphaScan(n, 2*deg/n, 2*deg)
    scan.setWavelength(1.54*angstrom)
    return ba.SpecularSimulation(scan, sample)


if __name__ == '__main__':
    sample = get_sample()
    simulation = get_simulation(sample)
    result = simulation.simulate()
    bp.plot_simulation_result(result)
    plt.show()
auto/Examples/specular/AlternatingLayers1.py

For a discussion of the content of this script, see simulation/reflectometry.

From the command line

At the command prompt in a terminal, launch the script with the command

python AlternatingLayers1.py

(on systems that still have Python2, the command may rather be python3).

As result, a MatPlotLib window should pop up, and display this reflectometry curve:

Short call (Linux, Mac)

Under a Unix shell, the script can also be launched without typing python at the command prompt:

AlternatingLayers1.py

This is made possible by the line “#!/usr/bin/env python3” on top of the script. It may be necessary to make the script executable by

chmod a+x AlternatingLayers1.py