Proposition to give access to geometry properties within the user-def…

…ined stats. docs modification
perrygeo · Jun 15, 2019 · 1db2a33 · 1db2a33
1 parent 910455c
commit 1db2a33
Show file tree

Hide file tree

Showing 2 changed files with 25 additions and 2 deletions.
diff --git a/docs/manual.rst b/docs/manual.rst
@@ -174,6 +174,20 @@ then use it in your ``zonal_stats`` call like so::
     ...             add_stats={'mymean':mymean})
     [{'count': 75, 'mymean': 14.660084635416666}, {'count': 50, 'mymean': 56.605761718750003}]
 
+To have access to geometry properties, a dictionnary can be passed to the user-defined function::
+
+    >>> def mymean_prop(x,prop):
+    ...     return np.ma.mean(x) * prop['id']
+
+then use it in your ``zonal_stats`` call like so::
+
+    >>> zonal_stats("tests/data/polygons.shp",
+    ...             "tests/data/slope.tif",
+    ...             stats="count",
+    ...             add_stats={'mymean_prop':mymean_prop},
+    ...             properties=['id'])
+    [{'count': 75, 'mymean_prop': 14.660084635416666}, {'count': 50, 'mymean_prop': 113.2115234375}]
+
 
 GeoJSON output
 ^^^^^^^^^^^^^^

diff --git a/src/rasterstats/main.py b/src/rasterstats/main.py
@@ -45,7 +45,8 @@ def gen_zonal_stats(
         zone_func=None,
         raster_out=False,
         prefix=None,
-        geojson_out=False, **kwargs):
+        geojson_out=False,
+        properties=None, **kwargs):
     """Zonal statistics of raster values aggregated to vector geometries.
 
     Parameters
@@ -112,6 +113,9 @@ def gen_zonal_stats(
         with zonal stats appended as additional properties.
         Use with `prefix` to ensure unique and meaningful property names.
 
+    properties: list of str, , optional
+        Property names of the geo-like python objects to be used in the user-defined stats.
+        
     Returns
     -------
     generator of dicts (if geojson_out is False)
@@ -146,6 +150,8 @@ def gen_zonal_stats(
         features_iter = read_features(vectors, layer)
         for _, feat in enumerate(features_iter):
             geom = shape(feat['geometry'])
+            if properties:
+                prop_dic = {k: feat['properties'][k] for k in properties}
 
             if 'Point' in geom.type:
                 geom = boxify_points(geom, rast)
@@ -254,7 +260,10 @@ def gen_zonal_stats(
 
             if add_stats is not None:
                 for stat_name, stat_func in add_stats.items():
-                    feature_stats[stat_name] = stat_func(masked)
+                    try:
+                        feature_stats[stat_name] = stat_func(masked, prop_dic)
+                    except:
+                        feature_stats[stat_name] = stat_func(masked)
 
             if raster_out:
                 feature_stats['mini_raster_array'] = masked