Remove empty horizon component from irradiance.haydavies (#2788)

* Remove empty horizon brightening component from haydavies

* Change OrderedDict to Dict

* Apply suggestion from @AdamRJensen

* Add what's new entry

* Update docs/sphinx/source/whatsnew/v0.16.0.rst

Co-authored-by: Adam R. Jensen <39184289+AdamRJensen@users.noreply.github.com>

* Change Dict to dict

* Update docs/sphinx/source/whatsnew/v0.16.0.rst

Co-authored-by: Cliff Hansen <cwhanse@sandia.gov>

* Apply suggestion from @cwhanse

Co-authored-by: Cliff Hansen <cwhanse@sandia.gov>

* Apply suggestion from @cwhanse

Co-authored-by: Cliff Hansen <cwhanse@sandia.gov>

---------

Co-authored-by: Adam R. Jensen <39184289+AdamRJensen@users.noreply.github.com>
Co-authored-by: Cliff Hansen <cwhanse@sandia.gov>

Author: 3 people

docs/sphinx/source/whatsnew/v0.16.0.rst

@@ -0,0 +1,48 @@
+.. _whatsnew_0_16_0:
+
+
+v0.16.0
+-----------------------
+
+Breaking Changes
+~~~~~~~~~~~~~~~~
+* Remove empty ``poa_horizon`` key from the ``diffuse_components`` output of
+  :py:func:`pvlib.irradiance.haydavies`.
+  (:pull:`2788`)
+
+
+Deprecations
+~~~~~~~~~~~~
+
+
+Bug fixes
+~~~~~~~~~
+
+
+Enhancements
+~~~~~~~~~~~~
+
+
+Documentation
+~~~~~~~~~~~~~
+
+
+Testing
+~~~~~~~
+
+
+Benchmarking
+~~~~~~~~~~~~
+
+
+Requirements
+~~~~~~~~~~~~
+
+
+Maintenance
+~~~~~~~~~~~
+
+
+Contributors
+~~~~~~~~~~~~
+

pvlib/irradiance.py

@@ -787,7 +787,7 @@ def haydavies(surface_tilt, surface_azimuth, dhi, dni, dni_extra,
 
     Returns
     --------
-    numeric, OrderedDict, or DataFrame
+    numeric, dict, or DataFrame
         Return type controlled by ``return_components`` argument.
         If `False`, ``sky_diffuse`` is returned.
         If `True`, ``diffuse_components`` is returned.
@@ -796,13 +796,11 @@ def haydavies(surface_tilt, surface_azimuth, dhi, dni, dni_extra,
         The sky diffuse component of the solar radiation on a tilted
         surface. [Wm⁻²]
 
-    diffuse_components : OrderedDict (array input) or DataFrame (Series input)
+    diffuse_components : dict (array input) or DataFrame (Series input)
         Keys/columns are:
             * poa_sky_diffuse: Total sky diffuse
             * poa_isotropic
             * poa_circumsolar
-            * poa_horizon (always zero, not accounted for by the
-              Hay-Davies model)
 
     Notes
     ------
@@ -860,14 +858,11 @@ def haydavies(surface_tilt, surface_azimuth, dhi, dni, dni_extra,
     sky_diffuse = poa_isotropic + poa_circumsolar
 
     if return_components:
-        diffuse_components = OrderedDict()
-        diffuse_components['poa_sky_diffuse'] = sky_diffuse
-
-        # Calculate the individual components
-        diffuse_components['poa_isotropic'] = poa_isotropic
-        diffuse_components['poa_circumsolar'] = poa_circumsolar
-        diffuse_components['poa_horizon'] = np.where(
-            np.isnan(diffuse_components['poa_isotropic']), np.nan, 0.)
+        diffuse_components = {
+            'poa_sky_diffuse': sky_diffuse,
+            'poa_isotropic': poa_isotropic,
+            'poa_circumsolar': poa_circumsolar
+        }
 
         if isinstance(sky_diffuse, pd.Series):
             diffuse_components = pd.DataFrame(diffuse_components)

tests/test_irradiance.py

@@ -209,13 +209,11 @@ def test_haydavies(irrad_data, ephem_data, dni_et):
 
 
 def test_haydavies_components(irrad_data, ephem_data, dni_et):
-    keys = ['poa_sky_diffuse', 'poa_isotropic', 'poa_circumsolar',
-            'poa_horizon']
+    keys = ['poa_sky_diffuse', 'poa_isotropic', 'poa_circumsolar']
     expected = pd.DataFrame(np.array(
         [[0, 27.1775, 102.9949, 33.1909],
          [0, 27.1775, 30.1818, 27.9837],
-         [0, 0, 72.8130, 5.2071],
-         [0, 0, 0, 0]]).T,
+         [0, 0, 72.8130, 5.2071]]).T,
         columns=keys,
         index=irrad_data.index
     )