notebooks/07-plot-graph-over-shape.ipynb

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    "# Use OSMnx to plot street network over place shape\n",
    "\n",
    "Author: [Geoff Boeing](https://geoffboeing.com/)\n",
    "\n",
    "This example uses Portland, Maine - a city with several islands within its municipal boundaries. Thus, we set `retain_all=True` when getting the network so that we keep all the graph components, not just the largest connected component.\n",
    "\n",
    "  - [Overview of OSMnx](http://geoffboeing.com/2016/11/osmnx-python-street-networks/)\n",
    "  - [GitHub repo](https://github.com/gboeing/osmnx)\n",
    "  - [Examples, demos, tutorials](https://github.com/gboeing/osmnx-examples)\n",
    "  - [Documentation](https://osmnx.readthedocs.io/en/stable/)\n",
    "  - [Journal article/citation](http://geoffboeing.com/publications/osmnx-complex-street-networks/)"
   ]
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   "source": [
    "import matplotlib.pyplot as plt\n",
    "import osmnx as ox\n",
    "from descartes import PolygonPatch\n",
    "from shapely.geometry import MultiPolygon\n",
    "from shapely.geometry import Polygon\n",
    "\n",
    "%matplotlib inline\n",
    "ox.config(log_console=True)\n",
    "ox.__version__"
   ]
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    "# get the place boundaries\n",
    "place = \"Portland, Maine\"\n",
    "gdf = ox.geocode_to_gdf(place)\n",
    "\n",
    "# get the street network, with retain_all=True to retain all the disconnected islands' networks\n",
    "G = ox.graph_from_place(place, network_type=\"drive\", retain_all=True)"
   ]
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    "# plot the network, but do not show it or close it yet\n",
    "fig, ax = ox.plot_graph(\n",
    "    G,\n",
    "    show=False,\n",
    "    close=False,\n",
    "    bgcolor=\"#333333\",\n",
    "    edge_color=\"w\",\n",
    "    edge_linewidth=0.3,\n",
    "    node_size=0,\n",
    ")\n",
    "\n",
    "# to this matplotlib axis, add the place shape as descartes polygon patches\n",
    "for geometry in gdf[\"geometry\"].tolist():\n",
    "    if isinstance(geometry, (Polygon, MultiPolygon)):\n",
    "        if isinstance(geometry, Polygon):\n",
    "            geometry = MultiPolygon([geometry])\n",
    "        for polygon in geometry:\n",
    "            patch = PolygonPatch(polygon, fc=\"k\", ec=\"#666666\", lw=1, alpha=1, zorder=-1)\n",
    "            ax.add_patch(patch)\n",
    "\n",
    "# optionally set up the axes extents\n",
    "margin = 0.02\n",
    "west, south, east, north = gdf.unary_union.bounds\n",
    "margin_ns = (north - south) * margin\n",
    "margin_ew = (east - west) * margin\n",
    "ax.set_ylim((south - margin_ns, north + margin_ns))\n",
    "ax.set_xlim((west - margin_ew, east + margin_ew))\n",
    "plt.show()"
   ]
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   "cell_type": "markdown",
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   "source": [
    "Notice this municipal boundary is an administrative boundary, not a physical boundary, so it represents jurisdictional bounds, not individual physical features like islands. To get individual islands' geometries, use the `geometries` module:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "islands = ox.geometries_from_place(place, tags={\"place\": [\"island\", \"islet\"]})\n",
    "islands.shape"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
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