.. DO NOT EDIT.
.. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY.
.. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE:
.. "examples/plot_quadtree_hanging.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_quadtree_hanging.py>`
        to download the full example code

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

.. _sphx_glr_examples_plot_quadtree_hanging.py:


QuadTree: Hanging Nodes
=======================

You can give the refine method a function, which is evaluated on every
cell of the TreeMesh.

Occasionally it is useful to initially refine to a constant level
(e.g. 3 in this 32x32 mesh). This means the function is first evaluated
on an 8x8 mesh (2^3).

.. GENERATED FROM PYTHON SOURCE LINES 13-45



.. image-sg:: /examples/images/sphx_glr_plot_quadtree_hanging_001.png
   :alt: plot quadtree hanging
   :srcset: /examples/images/sphx_glr_plot_quadtree_hanging_001.png
   :class: sphx-glr-single-img





.. code-block:: default

    import discretize
    import matplotlib.pyplot as plt


    def run(plotIt=True):
        M = discretize.TreeMesh([8, 8])

        def refine(cell):
            xyz = cell.center
            dist = ((xyz - [0.25, 0.25]) ** 2).sum() ** 0.5
            if dist < 0.25:
                return 3
            return 2

        M.refine(refine)
        if plotIt:
            M.plot_grid(nodes=True, centers=True, faces_x=True)
            plt.legend(
                (
                    "Nodes",
                    "Hanging Nodes",
                    "Cell Centers",
                    "X faces",
                    "Hanging X faces",
                    "Grid",
                )
            )


    if __name__ == "__main__":
        run()
        plt.show()


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

   **Total running time of the script:** (0 minutes 0.144 seconds)


.. _sphx_glr_download_examples_plot_quadtree_hanging.py:

.. only:: html

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




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

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

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

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


.. only:: html

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

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