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

.. only:: html

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

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

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

.. _sphx_glr_examples_plot_polar_horns.py:


Polar horns
===========

.. GENERATED FROM PYTHON SOURCE LINES 7-8

First, some imports.

.. GENERATED FROM PYTHON SOURCE LINES 8-19

.. code-block:: Python


    from astroplan import Observer
    from astropy.coordinates import ITRS
    from astropy.time import Time
    from astropy import units as u
    from astropy_healpix import HEALPix
    from dorado.scheduling.constraints import TrappedParticleFluxConstraint
    from ligo.skymap import plot  # noqa: F401
    from matplotlib import pyplot as plt
    import numpy as np








.. GENERATED FROM PYTHON SOURCE LINES 20-21

Create trapped particle constraint.

.. GENERATED FROM PYTHON SOURCE LINES 21-28

.. code-block:: Python


    constraint = TrappedParticleFluxConstraint(
        flux=100 * u.cm**-2 * u.s**-1,
        energy=1 * u.MeV,
        particle='e',
        solar='max')








.. GENERATED FROM PYTHON SOURCE LINES 29-30

Evaluate the constraint on a HEALPix grid in ITRS coordinates.

.. GENERATED FROM PYTHON SOURCE LINES 30-45

.. code-block:: Python


    obstime = Time('2021-01-01')
    frame = ITRS(obstime=obstime)
    healpix = HEALPix(64, frame=frame)
    locations = healpix.healpix_to_skycoord(np.arange(healpix.npix))
    locations = ITRS(lon=locations.spherical.lon,
                     lat=locations.spherical.lat,
                     distance=1 * u.Rearth + 600 * u.km,
                     representation_type='spherical')
    locations = locations.earth_location

    constraint_values = np.asarray([
        constraint.compute_constraint(obstime, Observer(location))
        for location in locations])





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

 .. code-block:: none

    /home/docs/checkouts/readthedocs.org/user_builds/dorado-scheduling/envs/latest/lib/python3.11/site-packages/numpy/lib/function_base.py:2455: RuntimeWarning: invalid value encountered in aep8 (vectorized)
      outputs = ufunc(*inputs)




.. GENERATED FROM PYTHON SOURCE LINES 46-47

Plot a map of the true/false value of the constraint.

.. GENERATED FROM PYTHON SOURCE LINES 47-51

.. code-block:: Python


    ax = plt.axes(projection='geo mollweide')
    ax.imshow_hpx(constraint_values, order='nearest-neighbor', cmap='binary_r')
    ax.grid()



.. image-sg:: /examples/images/sphx_glr_plot_polar_horns_001.png
   :alt: plot polar horns
   :srcset: /examples/images/sphx_glr_plot_polar_horns_001.png
   :class: sphx-glr-single-img






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

   **Total running time of the script:** (4 minutes 4.699 seconds)


.. _sphx_glr_download_examples_plot_polar_horns.py:

.. only:: html

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

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

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

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

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


.. only:: html

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

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