Merge pull request #194 from geopandas/clean/add-kwarg-null-value

Always use kwargs when calling _series_unary_op()

geopandas/base.py

@@ -95,12 +95,12 @@ def _invalidate_sindex(self):
     @property
     def area(self):
         """Return the area of each geometry in the GeoSeries"""
-        return _series_unary_op(self, 'area', np.nan)
+        return _series_unary_op(self, 'area', null_value=np.nan)
 
     @property
     def geom_type(self):
         """Return the geometry type of each geometry in the GeoSeries"""
-        return _series_unary_op(self, 'geom_type', None)
+        return _series_unary_op(self, 'geom_type', null_value=None)
 
     @property
     def type(self):
@@ -110,22 +110,22 @@ def type(self):
     @property
     def length(self):
         """Return the length of each geometry in the GeoSeries"""
-        return _series_unary_op(self, 'length', np.nan)
+        return _series_unary_op(self, 'length', null_value=np.nan)
 
     @property
     def is_valid(self):
         """Return True for each valid geometry, else False"""
-        return _series_unary_op(self, 'is_valid')
+        return _series_unary_op(self, 'is_valid', null_value=False)
 
     @property
     def is_empty(self):
         """Return True for each empty geometry, False for non-empty"""
-        return _series_unary_op(self, 'is_empty')
+        return _series_unary_op(self, 'is_empty', null_value=False)
 
     @property
     def is_simple(self):
         """Return True for each simple geometry, else False"""
-        return _series_unary_op(self, 'is_simple', False)
+        return _series_unary_op(self, 'is_simple', null_value=False)
 
     @property
     def is_ring(self):
@@ -168,7 +168,7 @@ def exterior(self):
     def interiors(self):
         """Return the interior rings of each polygon"""
         # TODO: return empty list or None for non-polygons
-        return _series_unary_op(self, 'interiors')
+        return _series_unary_op(self, 'interiors', null_value=False)
 
     def representative_point(self):
         """Return a GeoSeries of points guaranteed to be in each geometry"""