.. only:: html

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

        Click :ref:`here <sphx_glr_download_auto_examples_plot_geodataframe.py>`     to download the full example code
    .. rst-class:: sphx-glr-example-title

    .. _sphx_glr_auto_examples_plot_geodataframe.py:


Alpha Shapes with GeoPandas GeoDataFrame
========================================

This example opens a shapefile with GeoPandas, and generates a new GeoDataFrame
with the alpha shape as its only geometry.  It then plots the geodataframe with
cartopy.



.. image:: /auto_examples/images/sphx_glr_plot_geodataframe_001.png
    :alt: plot geodataframe
    :class: sphx-glr-single-img






.. code-block:: default
   :lineno-start: 10

    import os
    import matplotlib.pyplot as plt
    import cartopy.crs as ccrs
    import geopandas
    import alphashape

    try:
        DATA = os.path.abspath(os.path.join(os.path.dirname(__file__), 'data'))
    except NameError:
        DATA = os.path.abspath(os.path.join(os.path.dirname(os.getcwd()),
                                            'examples', 'data'))

    # Define input points
    gdf = geopandas.read_file(os.path.join(DATA, 'Public_Airports_March2018.shp'))

    # Generate the alpha shape
    alpha_shape = alphashape.alphashape(gdf)

    # Initialize plot
    ax = plt.axes(projection=ccrs.PlateCarree())

    # Plot input points
    gdf_proj = gdf.to_crs(ccrs.Robinson().proj4_init)
    ax.scatter([p.x for p in gdf_proj['geometry']],
               [p.y for p in gdf_proj['geometry']],
               transform=ccrs.Robinson())

    # Plot alpha shape
    ax.add_geometries(
        alpha_shape.to_crs(ccrs.Robinson().proj4_init)['geometry'],
        crs=ccrs.Robinson(), alpha=.2)

    plt.show()


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

   **Total running time of the script:** ( 0 minutes  55.497 seconds)


.. _sphx_glr_download_auto_examples_plot_geodataframe.py:


.. only :: html

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



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

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



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

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


.. only:: html

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

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