
.. DO NOT EDIT.
.. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY.
.. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE:
.. "gallery/inverse/fit_sphere_scattering.py"
.. LINE NUMBERS ARE GIVEN BELOW.

.. only:: html

    .. note::
        :class: sphx-glr-download-link-note

        :ref:`Go to the end <sphx_glr_download_gallery_inverse_fit_sphere_scattering.py>`
        to download the full example code.

.. rst-class:: sphx-glr-example-title

.. _sphx_glr_gallery_inverse_fit_sphere_scattering.py:


Fit an isolated-sphere scattering measurement
==============================================

Recover a sphere diameter from one dimensionless scattering-efficiency
measurement. This uses the isolated-particle Mie model. It does not represent
multiple scattering, near-field coupling, or positional correlations in dense
particle systems.

The fitted diameter is approximately 180 nanometers within the stated bounds.
The prediction is a scalar dimensionless efficiency. One noiseless channel
with a fixed refractive index demonstrates parameter recovery; it does not
establish uniqueness over a wider diameter range.

.. GENERATED FROM PYTHON SOURCE LINES 15-53


.. rst-class:: sphx-glr-script-out

 .. code-block:: none

    iteration    1 | objective 0.035303537 | step 0.1    iteration    2 | objective 0.0083962553 | step 0.1    iteration    3 | objective 0.00081984712 | step 0.1    iteration    4 | objective 0.00081984712 | step 0.05    iteration    5 | objective 0.00081984712 | step 0.025    iteration    6 | objective 1.2293524e-05 | step 0.025    iteration    7 | objective 1.2293524e-05 | step 0.0125    iteration    8 | objective 1.2293524e-05 | step 0.00625    iteration    9 | objective 1.2293524e-05 | step 0.00313    iteration   10 | objective 1.9310194e-07 | step 0.00313    iteration   11 | objective 1.9310194e-07 | step 0.00156    iteration   12 | objective 1.9310194e-07 | step 0.000781    iteration   13 | objective 1.9310194e-07 | step 0.000391    iteration   14 | objective 3.0152357e-09 | step 0.000391    iteration   15 | objective 3.0152357e-09 | step 0.000195    iteration   16 | objective 3.0152357e-09 | step 9.77e-05    iteration   17 | objective 3.0152357e-09 | step 4.88e-05    iteration   18 | objective 4.711693e-11 | step 4.88e-05    iteration   19 | objective 4.711693e-11 | step 2.44e-05    iteration   20 | objective 4.711693e-11 | step 1.22e-05    iteration   21 | objective 4.711693e-11 | step 6.1e-06    iteration   22 | objective 7.3619446e-13 | step 6.1e-06    iteration   23 | objective 7.3619446e-13 | step 3.05e-06    iteration   24 | objective 7.3619446e-13 | step 1.53e-06    iteration   25 | objective 7.3619446e-13 | step 7.63e-07    converged after 25 iterations | objective 7.3619446e-13
    converged (52 model evaluations)
    objective = 0.000000


|

.. code-block:: Python

    from PyMieSim import (
        Measure,
        FitParameter, MeasuredData, PlaneWave, PolarizationState, Simulation, Sphere,
        fit_parameters, ureg,
    )

    source = PlaneWave(
        wavelength=532 * ureg.nanometer,
        polarization=PolarizationState(angle=0 * ureg.degree),
        amplitude=1 * ureg.volt / ureg.meter,
    )
    target_diameter = 180 * ureg.nanometer
    target = Simulation(
        scatterer=Sphere(diameter=target_diameter, material=1.59, medium=1.0),
        source=source,
    ).get(Measure.QSCA)


    def model(parameters):
        sphere = Sphere(diameter=parameters["diameter"], material=1.59, medium=1.0)
        return Simulation(scatterer=sphere, source=source).get(Measure.QSCA)


    result = fit_parameters(
        model=model,
        observation=MeasuredData(values=target),
        parameters=[
            FitParameter(
                name="diameter",
                initial=130 * ureg.nanometer,
                bounds=(80 * ureg.nanometer, 260 * ureg.nanometer),
            )
        ],
        max_iterations=250,
        show_progress=True,
    )

    print(result.summary())


.. rst-class:: sphx-glr-timing

   **Total running time of the script:** (0 minutes 0.013 seconds)


.. _sphx_glr_download_gallery_inverse_fit_sphere_scattering.py:

.. only:: html

  .. container:: sphx-glr-footer sphx-glr-footer-example

    .. container:: sphx-glr-download sphx-glr-download-jupyter

      :download:`Download Jupyter notebook: fit_sphere_scattering.ipynb <fit_sphere_scattering.ipynb>`

    .. container:: sphx-glr-download sphx-glr-download-python

      :download:`Download Python source code: fit_sphere_scattering.py <fit_sphere_scattering.py>`

    .. container:: sphx-glr-download sphx-glr-download-zip

      :download:`Download zipped: fit_sphere_scattering.zip <fit_sphere_scattering.zip>`


.. only:: html

 .. rst-class:: sphx-glr-signature

    `Gallery generated by Sphinx-Gallery <https://sphinx-gallery.github.io>`_