remove unused tmy._recolumn 'inplace' kwarg

remove unused tmy._recolumn 'inplace' kwarg

Author: KonstantinTr

docs/sphinx/source/whatsnew/v0.5.1.rst

@@ -21,6 +21,7 @@ Bug fixes
 * ModelChain.prepare_inputs and ModelChain.complete_irradiance now
   correctly pass the 'solar_position_method' argument to
   solarposition.get_solarposition (:issue:`377`)
+* Fixed usage of inplace parameter for tmy._recolumn (:issue:`342`)
 
 Enhancements
 ~~~~~~~~~~~~

pvlib/tmy.py

@@ -187,7 +187,7 @@ def readtmy3(filename=None, coerce_year=None, recolumn=True):
         index_col='datetime')
 
     if recolumn:
-        _recolumn(data)  # rename to standard column names
+        data = _recolumn(data)  # rename to standard column names
 
     data = data.tz_localize(int(meta['TZ']*3600))
 
@@ -213,7 +213,7 @@ def _parsedate(ymd, hour, year=None):
     return true_date
 
 
-def _recolumn(tmy3_dataframe, inplace=True):
+def _recolumn(tmy3_dataframe):
     """
     Rename the columns of the TMY3 DataFrame.
 
@@ -251,7 +251,7 @@ def _recolumn(tmy3_dataframe, inplace=True):
 
     mapping = dict(zip(raw_columns.split(','), new_columns))
 
-    return tmy3_dataframe.rename(columns=mapping, inplace=True)
+    return tmy3_dataframe.rename(columns=mapping)
 
 
 def readtmy2(filename):