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

.. only:: html

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

        :ref:`Go to the end <sphx_glr_download_user-guide_model-gallery_spectral_plot_piecewise_norm_spectral.py>`
        to download the full example code. or to run this example in your browser via Binder

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

.. _sphx_glr_user-guide_model-gallery_spectral_plot_piecewise_norm_spectral.py:


.. _piecewise-norm-spectral:

Piecewise  norm spectral model
==============================

This model parametrises a piecewise spectral correction
with a free norm parameter at each fixed energy node.

.. GENERATED FROM PYTHON SOURCE LINES 12-15

Example plot
------------
Here is an example plot of the model:

.. GENERATED FROM PYTHON SOURCE LINES 15-34

.. code-block:: Python


    from astropy import units as u
    import matplotlib.pyplot as plt
    from gammapy.modeling.models import (
        Models,
        PiecewiseNormSpectralModel,
        PowerLawSpectralModel,
        SkyModel,
    )

    energy_bounds = [0.1, 100] * u.TeV
    model = PiecewiseNormSpectralModel(
        energy=[0.1, 1, 3, 10, 30, 100] * u.TeV,
        norms=[1, 3, 8, 10, 8, 2],
    )
    model.plot(energy_bounds, yunits=u.Unit(""))
    plt.grid(which="both")





.. image-sg:: /user-guide/model-gallery/spectral/images/sphx_glr_plot_piecewise_norm_spectral_001.png
   :alt: plot piecewise norm spectral
   :srcset: /user-guide/model-gallery/spectral/images/sphx_glr_plot_piecewise_norm_spectral_001.png
   :class: sphx-glr-single-img





.. GENERATED FROM PYTHON SOURCE LINES 35-38

YAML representation
-------------------
Here is an example YAML file using the model:

.. GENERATED FROM PYTHON SOURCE LINES 38-44

.. code-block:: Python


    model = model * PowerLawSpectralModel()
    model = SkyModel(spectral_model=model, name="piecewise-norm-model")
    models = Models([model])

    print(models.to_yaml())




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

 .. code-block:: none

    components:
    -   name: piecewise-norm-model
        type: SkyModel
        spectral:
            type: CompoundSpectralModel
            model1:
                type: PiecewiseNormSpectralModel
                parameters:
                -   name: norm_0
                    value: 1.0
                -   name: norm_1
                    value: 3.0
                -   name: norm_2
                    value: 8.0
                -   name: norm_3
                    value: 10.0
                -   name: norm_4
                    value: 8.0
                -   name: norm_5
                    value: 2.0
                energy:
                    data:
                    - 0.1
                    - 1.0
                    - 3.0
                    - 10.0
                    - 30.0
                    - 100.0
                    unit: TeV
                interp: log
            model2:
                type: PowerLawSpectralModel
                parameters:
                -   name: index
                    value: 2.0
                -   name: amplitude
                    value: 1.0e-12
                    unit: cm-2 s-1 TeV-1
                -   name: reference
                    value: 1.0
                    unit: TeV
            operator: mul
    metadata:
        creator: Gammapy 1.3.dev241+g0271bebfc
        date: '2024-05-03T15:02:26.704218'
        origin: null






.. _sphx_glr_download_user-guide_model-gallery_spectral_plot_piecewise_norm_spectral.py:

.. only:: html

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

    .. container:: binder-badge

      .. image:: images/binder_badge_logo.svg
        :target: https://mybinder.org/v2/gh/gammapy/gammapy-webpage/main?urlpath=lab/tree/notebooks/dev/user-guide/model-gallery/spectral/plot_piecewise_norm_spectral.ipynb
        :alt: Launch binder
        :width: 150 px

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

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

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

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


.. only:: html

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

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