[polygons] Polygon area calculations

scripts/geodata/polygons/area.py

@@ -0,0 +1,26 @@
+import pyproj
+
+from functools import partial
+from shapely.ops import transform
+from shapely.geometry import Polygon
+
+
+def polygon_area(poly):
+    return transform(
+        partial(pyproj.transform,
+                pyproj.Proj(init='EPSG:4326'),
+                pyproj.Proj(proj='aea',
+                            lat1=poly.bounds[1],
+                            lat2=poly.bounds[2],
+                            )
+                ),
+        poly
+    ).area
+
+
+def polygon_bounding_box_area(poly):
+    bbox = poly.bounds
+    p = Polygon([(bbox[0], bbox[3]), (bbox[0], bbox[1]),
+                 (bbox[2], bbox[1]), (bbox[2], bbox[3]),
+                 ])
+    return polygon_area(p)