.. DO NOT EDIT.
.. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY.
.. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE:
.. "school-tutorials/trilmax-2025/1_python-library/plot_5_energy.py"
.. LINE NUMBERS ARE GIVEN BELOW.

.. only:: html

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

        :ref:`Go to the end <sphx_glr_download_school-tutorials_trilmax-2025_1_python-library_plot_5_energy.py>`
        to download the full example code.

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

.. _sphx_glr_school-tutorials_trilmax-2025_1_python-library_plot_5_energy.py:


Classical Energy
****************


.. admonition:: Tutorial tasks

    *   Compute classical energy of one of the Hamiltonians from the previous tasks.
    *   Change the convention of the spin Hamiltonian and re-compute the energy. Does it
        change?
    *   Use the set of Hamiltonians from :ref:`trilmax-2025_spinham_arithmetics`.
        Optimize the spin direction for the full Hamiltonian. Use them to compute
        energy contributions of every term.
    *   (extra) Create a Hamiltonian of the ferromagnet with an easy magnetic axis.
        Find out numerically the value of the magnetic field that is applied
        perpendicular to the easy axis, which fully orients the spins along the magnetic
        field.

Classical energy of the spin Hamiltonian is implemented in a separate class.

.. GENERATED FROM PYTHON SOURCE LINES 21-28

.. code-block:: Python


    import magnopy

    spinham = magnopy.examples.cubic_ferro_nn(S=1, J_21=(-1, 0, 1))

    energy = magnopy.Energy(spinham=spinham)








.. GENERATED FROM PYTHON SOURCE LINES 29-30

This object can be used to simply compute the energy for some set of spin directions

.. GENERATED FROM PYTHON SOURCE LINES 30-35

.. code-block:: Python


    print(energy(spin_directions=[[1, 0, 0]]))
    print(energy(spin_directions=[[0, 1, 0]]))
    print(energy(spin_directions=[[0, 0, 1]]))





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

 .. code-block:: none

    -4.0
    -3.0
    -2.0




.. GENERATED FROM PYTHON SOURCE LINES 36-38

or to optimize spin directions within unit cell and get the configuration of some local
minima

.. GENERATED FROM PYTHON SOURCE LINES 38-41

.. code-block:: Python


    optimized_sd = energy.optimize()





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

 .. code-block:: none

    ─────┬─────────────┬─────────────┬─────────────
    step │     E_0     │  delta E_0  │ max torque 
    ─────┴─────────────┴─────────────┴─────────────
    1       -3.8144091     0.5227305     0.7795155
    2       -3.9177110     0.1033019     0.6757774
    3       -3.9701722     0.0524612     0.3862030
    4       -3.9996792     0.0295069     0.0361254
    5       -3.9998632     0.0001840     0.0281246
    6       -3.9999656     0.0001025     0.0117617
    7       -3.9999929     0.0000273     0.0069941
    8       -3.9999954     0.0000024     0.0046177
    9       -3.9999977     0.0000023     0.0042198
    10      -3.9999992     0.0000015     0.0019175
    11      -3.9999996     0.0000005     0.0016791
    12      -4.0000000     0.0000003     0.0003172
    13      -4.0000000     0.0000000     0.0002358
    14      -4.0000000     0.0000000     0.0000697
    15      -4.0000000     0.0000000     0.0000598
    16      -4.0000000     0.0000000     0.0000160
    17      -4.0000000     0.0000000     0.0000126
    18      -4.0000000     0.0000000     0.0000033
    ───────────────────────────────────────────────




.. GENERATED FROM PYTHON SOURCE LINES 42-43

see :py:class:`magnopy.Energy` for more details.

.. GENERATED FROM PYTHON SOURCE LINES 43-48

.. code-block:: Python


    print(optimized_sd)
    print(energy(optimized_sd))






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

 .. code-block:: none

    [[ 1.00000000e+00 -1.43745602e-06 -4.01553907e-07]]
    -3.9999999999976126





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

   **Total running time of the script:** (0 minutes 0.038 seconds)


.. _sphx_glr_download_school-tutorials_trilmax-2025_1_python-library_plot_5_energy.py:

.. only:: html

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

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

      :download:`Download Jupyter notebook: plot_5_energy.ipynb <plot_5_energy.ipynb>`

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

      :download:`Download Python source code: plot_5_energy.py <plot_5_energy.py>`

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

      :download:`Download zipped: plot_5_energy.zip <plot_5_energy.zip>`


.. only:: html

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

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