Update chapter 14 code

Author: rossant

chapter14_graphgeo/02_airports.ipynb

@@ -4,7 +4,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "# Drawing airports and flight routes with NetworkX"
+    "# Drawing flight routes with NetworkX"
    ]
   },
   {
@@ -320,6 +320,7 @@
     "fig, ax = plt.subplots(1, 1, figsize=(12, 8),\n",
     "                       subplot_kw=dict(projection=crs))\n",
     "ax.coastlines()\n",
+    "# Extent of continental US.\n",
     "ax.set_extent([-128, -62, 20, 50])\n",
     "nx.draw_networkx(sg, ax=ax,\n",
     "                 font_size=16,\n",

chapter14_graphgeo/03_dag.ipynb

@@ -189,7 +189,7 @@
     }
    ],
    "source": [
-    "nx.draw_shell(graph, with_labels=True,\n",
+    "nx.draw_shell(graph,\n",
     "              node_color=colors,\n",
     "              cmap=plt.cm.Blues,\n",
     "              font_size=8,\n",

chapter14_graphgeo/06_gis.ipynb

@@ -94,7 +94,7 @@
    ],
    "source": [
     "fig, ax = plt.subplots(1, 1, figsize=(6, 8),\n",
-    "                      subplot_kw=dict(projection=crs))\n",
+    "                       subplot_kw=dict(projection=crs))\n",
     "draw_africa(ax)"
    ]
   },

chapter14_graphgeo/07_gps.ipynb

@@ -97,7 +97,6 @@
     "# from https://stackoverflow.com/a/8859667/1595060\n",
     "EARTH_R = 6372.8\n",
     "\n",
-    "\n",
     "def geocalc(lat0, lon0, lat1, lon1):\n",
     "    \"\"\"Return the distance (in km) between two points in\n",
     "    geographical coordinates.\"\"\"\n",