* changes permitting the creation of a location object from epw metadata.

- 2 options included: 'from_epw' or 'from_tmy_or_epw', to discuss

Author: tylunel

pvlib/location.py

@@ -85,46 +85,79 @@ def __repr__(self):
             ('{}: {}'.format(attr, getattr(self, attr)) for attr in attrs)))
 
     @classmethod
-    def from_tmy(cls, tmy_metadata, tmy_data=None, **kwargs):
+    def from_tmy_or_epw(cls, weather_metadata, weather_data=None, **kwargs):
         """
         Create an object based on a metadata
-        dictionary from tmy2 or tmy3 data readers.
+        dictionary from tmy2, tmy3 or epw data readers.
 
         Parameters
         ----------
-        tmy_metadata : dict
-            Returned from tmy.readtmy2 or tmy.readtmy3
-        tmy_data : None or DataFrame, default None
-            Optionally attach the TMY data to this object.
+        weather_metadata : dict
+            Returned from tmy.readtmy2, tmy.readtmy3 or epw.read_epw
+        weather_data : None or DataFrame, default None
+            Optionally attach the weather data to this object.
 
         Returns
         -------
         Location object (or the child class of Location that you
         called this method from).
         """
-        # not complete, but hopefully you get the idea.
-        # might need code to handle the difference between tmy2 and tmy3
-
-        # determine if we're dealing with TMY2 or TMY3 data
-        tmy2 = tmy_metadata.get('City', False)
-
-        latitude = tmy_metadata['latitude']
-        longitude = tmy_metadata['longitude']
+        # determine if we're dealing with TMY2, TMY3 or data formatted
+        # in .epw (Note that TMY2 and TMY3 can be formatted in epw sometimes)
+        tmy2 = weather_metadata.get('City', False)
+        tmy3 = weather_metadata.get('Name', False)
 
         if tmy2:
-            name = tmy_metadata['City']
+            name = weather_metadata['City']
+        elif tmy3:
+            name = weather_metadata['Name']
         else:
-            name = tmy_metadata['Name']
+            name = weather_metadata['city']
+
+        latitude = weather_metadata['latitude']
+        longitude = weather_metadata['longitude']
 
-        tz = tmy_metadata['TZ']
-        altitude = tmy_metadata['altitude']
+        tz = weather_metadata['TZ']
+        altitude = weather_metadata['altitude']
 
         new_object = cls(latitude, longitude, tz=tz, altitude=altitude,
                          name=name, **kwargs)
 
         # not sure if this should be assigned regardless of input.
-        if tmy_data is not None:
-            new_object.tmy_data = tmy_data
+        if weather_data is not None:
+            new_object.weather_data = weather_data
+
+        return new_object
+
+    @classmethod
+    def from_epw(cls, epw_metadata, epw_data=None, **kwargs):
+        """
+        Create a Location object based on a metadata
+        dictionary from epw data readers.
+
+        Parameters
+        ----------
+        epw_metadata : dict
+            Returned from epw.read_epw
+        epw_data : None or DataFrame, default None
+            Optionally attach the epw data to this object.
+
+        Returns
+        -------
+        Location object (or the child class of Location that you
+        called this method from).
+        """
+
+        latitude = epw_metadata['latitude']
+        longitude = epw_metadata['longitude']
+
+        name = epw_metadata['city']
+
+        tz = epw_metadata['TZ']
+        altitude = epw_metadata['altitude']
+
+        new_object = cls(latitude, longitude, tz=tz, altitude=altitude,
+                         name=name, **kwargs)
 
         return new_object
 

pvlib/test/test_location.py

@@ -214,22 +214,33 @@ def test_from_tmy_3():
     from test_tmy import tmy3_testfile
     from pvlib.iotools import read_tmy3
     data, meta = read_tmy3(tmy3_testfile)
-    loc = Location.from_tmy(meta, data)
+    loc = Location.from_tmy_or_epw(meta, data)
     assert loc.name is not None
     assert loc.altitude != 0
     assert loc.tz != 'UTC'
-    assert_frame_equal(loc.tmy_data, data)
+    assert_frame_equal(loc.weather_data, data)
 
 
 def test_from_tmy_2():
     from test_tmy import tmy2_testfile
     from pvlib.iotools import read_tmy2
     data, meta = read_tmy2(tmy2_testfile)
-    loc = Location.from_tmy(meta, data)
+    loc = Location.from_tmy_or_epw(meta, data)
     assert loc.name is not None
     assert loc.altitude != 0
     assert loc.tz != 'UTC'
-    assert_frame_equal(loc.tmy_data, data)
+    assert_frame_equal(loc.weather_data, data)
+
+
+def test_from_epw():
+    from test_epw import epw_testfile
+    from pvlib.iotools import read_epw
+    data, meta = read_epw(epw_testfile)
+    loc = Location.from_tmy_or_epw(meta, data)
+    assert loc.name is not None
+    assert loc.altitude != 0
+    assert loc.tz != 'UTC'
+    assert_frame_equal(loc.weather_data, data)
 
 
 def test_get_solarposition(expected_solpos, golden_mst):