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Author: cwhanse

pvlib/pvsystem.py

@@ -349,6 +349,9 @@ def get_irradiance(self, solar_zenith, solar_azimuth, dni, ghi, dhi,
         If passed as a tuple the length must be the same as the number of
         Arrays.
 
+        If `dni_extra` is omitted and parameters are passed as float, then
+        ``dni_extra=1367`` is assumed.
+
         Returns
         -------
         poa_irradiance : DataFrame or tuple of DataFrame
@@ -1112,6 +1115,11 @@ def get_irradiance(self, solar_zenith, solar_azimuth, dni, ghi, dhi,
             Column names are: ``'poa_global', 'poa_direct', 'poa_diffuse',
             'poa_sky_diffuse', 'poa_ground_diffuse'``.
 
+        Notes
+        -----
+        If `dni_extra` is omitted and parameters are passed as float, then
+        ``dni_extra=1367`` is assumed.
+
         See also
         --------
         :py:func:`pvlib.irradiance.get_total_irradiance`