BUG: fix plotting of dup indexed objects

doc/source/release.rst

@@ -125,6 +125,8 @@ pandas 0.13
     (:issue:`4455`)
   - Fixed Panel attribute naming conflict if item is named 'a'
     (:issue:`3440`)
+  - Fixed an issue where duplicate indexes were raising when plotting
+    (:issue:`4486`)
 
 pandas 0.12
 ===========

pandas/core/series.py

@@ -602,7 +602,6 @@ def _ixs(self, i, axis=0):
                 else:
                     return _index.get_value_at(self, i)
 
-
     @property
     def _is_mixed_type(self):
         return False
@@ -2646,8 +2645,10 @@ def reindex(self, index=None, method=None, level=None, fill_value=pa.NA,
                                                 level=level, limit=limit,
                                                 takeable=takeable)
 
-        # GH4246 (dispatch to a common method with frame to handle possibly duplicate index)
-        return self._reindex_with_indexers(new_index, indexer, copy=copy, fill_value=fill_value)
+        # GH4246 (dispatch to a common method with frame to handle possibly
+        # duplicate index)
+        return self._reindex_with_indexers(new_index, indexer, copy=copy,
+                                           fill_value=fill_value)
 
     def _reindex_with_indexers(self, index, indexer, copy, fill_value):
         new_values = com.take_1d(self.values, indexer, fill_value=fill_value)

pandas/tests/test_graphics.py

@@ -3,7 +3,7 @@
 import string
 import unittest
 
-from datetime import datetime, date
+from datetime import datetime, date, timedelta
 
 from pandas import Series, DataFrame, MultiIndex, PeriodIndex, date_range
 from pandas.compat import range, lrange, StringIO, lmap, lzip, u, zip
@@ -309,6 +309,16 @@ def test_invalid_kind(self):
         s = Series([1, 2])
         self.assertRaises(ValueError, s.plot, kind='aasdf')
 
+    @slow
+    def test_dup_datetime_index_plot(self):
+        dr1 = date_range('1/1/2009', periods=4)
+        dr2 = date_range('1/2/2009', periods=4)
+        index = dr1.append(dr2)
+        values = randn(index.size)
+        s = Series(values, index=index)
+        _check_plot_works(s.plot)
+
+
 
 class TestDataFramePlots(unittest.TestCase):
 

pandas/tools/plotting.py

@@ -1041,7 +1041,7 @@ def _get_xticks(self, convert_period=False):
                 """
                 x = index._mpl_repr()
             elif is_datetype:
-                self.data = self.data.reindex(index=index.order())
+                self.data = self.data.sort_index()
                 x = self.data.index._mpl_repr()
             else:
                 self._need_to_set_index = True