From c73909eb2d5cca44a6d168b7b217bdd00ca14b1e Mon Sep 17 00:00:00 2001
From: Kieran O'Mahony <kieranom@gmail.com>
Date: Mon, 5 Aug 2013 11:31:40 +1000
Subject: [PATCH] BUG: values array for non-unique, interleaved cols incorrect

---
 pandas/core/internals.py       |  9 +++++----
 pandas/tests/test_internals.py | 11 +++++++++++
 2 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/pandas/core/internals.py b/pandas/core/internals.py
index abe70e9037264..56a6c8081d556 100644
--- a/pandas/core/internals.py
+++ b/pandas/core/internals.py
@@ -1546,15 +1546,16 @@ def _interleave(self, items):
                 result[indexer] = block.get_values(dtype)
                 itemmask[indexer] = 1
 
-            if not itemmask.all():
-                raise AssertionError('Some items were not contained in blocks')
-
         else:
 
             # non-unique, must use ref_locs
             rl = self._set_ref_locs()
             for i, (block, idx) in enumerate(rl):
-                result[i] = block.iget(idx)
+                result[i] = block.get_values(dtype)[idx]
+                itemmask[i] = 1
+
+        if not itemmask.all():
+            raise AssertionError('Some items were not contained in blocks')
 
         return result
 
diff --git a/pandas/tests/test_internals.py b/pandas/tests/test_internals.py
index 6f13678339425..57827857e107a 100644
--- a/pandas/tests/test_internals.py
+++ b/pandas/tests/test_internals.py
@@ -457,6 +457,17 @@ def test_xs(self):
     def test_interleave(self):
         pass
 
+    def test_interleave_non_unique_cols(self):
+        df = DataFrame([
+            [Timestamp('20130101'), 3.5],
+            [Timestamp('20130102'), 4.5]],
+            columns=['x', 'x'],
+            index=[1, 2])
+
+        df_unique = df.copy()
+        df_unique.columns = ['x', 'y']
+        np.testing.assert_array_equal(df_unique.values, df.values)
+
     def test_consolidate(self):
         pass