From 80b5082a2c2a39ac9613e30168a18706a4d3088c Mon Sep 17 00:00:00 2001
From: John-Colvin <john.loughran.colvin@gmail.com>
Date: Mon, 3 Sep 2012 20:53:50 +0200
Subject: [PATCH 1/2] fixed row/col orientation for 2D arrays

Pytables createArray function uses the opposite convention to pandas
for row/col. Using the numpy transpose .T corrects for this without
copying the data and keeping the orientation of 1D arrays intact.
---
 pandas/io/pytables.py | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/pandas/io/pytables.py b/pandas/io/pytables.py
index d116337c80e4d..b7dce3d5c758a 100644
--- a/pandas/io/pytables.py
+++ b/pandas/io/pytables.py
@@ -686,7 +686,10 @@ def _read_index_node(self, node):
     def _write_array(self, group, key, value):
         if key in group:
             self.handle.removeNode(group, key)
-
+        
+        #Transform needed to interface with pytables row/col notation
+        value = value.T
+        
         if self.filters is not None:
             atom = None
             try:

From 4ff42dbcd4cc430f504cd8e53067581575fd949c Mon Sep 17 00:00:00 2001
From: John-Colvin <john.loughran.colvin@gmail.com>
Date: Mon, 3 Sep 2012 22:18:20 +0200
Subject: [PATCH 2/2] added tranposed attribute, used in _read_array
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

the transposed attribute keeps track of whether the data has been 
transposed, allowing it to be correctly read by _read_array.
Some minor rearrangement of _read_array was necessary to reduce
duplicate code.
---
 pandas/io/pytables.py | 23 ++++++++++++++++-------
 1 file changed, 16 insertions(+), 7 deletions(-)

diff --git a/pandas/io/pytables.py b/pandas/io/pytables.py
index b7dce3d5c758a..5820e447e5df5 100644
--- a/pandas/io/pytables.py
+++ b/pandas/io/pytables.py
@@ -704,6 +704,7 @@ def _write_array(self, group, key, value):
                                               value.shape,
                                               filters=self.filters)
                 ca[:] = value
+                getattr(group, key)._v_attrs.transposed = True
                 return
 
         if value.dtype.type == np.object_:
@@ -722,6 +723,8 @@ def _write_array(self, group, key, value):
                 getattr(group, key)._v_attrs.shape = value.shape
             else:
                 self.handle.createArray(group, key, value)
+                
+        getattr(group, key)._v_attrs.transposed = True
 
     def _write_table(self, group, items=None, index=None, columns=None,
                      values=None, append=False, compression=None):
@@ -961,23 +964,29 @@ def _read_array(group, key):
     import tables
     node = getattr(group, key)
     data = node[:]
+    attrs = node._v_attrs
+
+    transposed = getattr(attrs, 'transposed', False)
 
     if isinstance(node, tables.VLArray):
-        return data[0]
+        ret = data[0]
     else:
-        attrs = node._v_attrs
-
         dtype = getattr(attrs, 'value_type', None)
         shape = getattr(attrs, 'shape', None)
 
         if shape is not None:
             # length 0 axis
-            return np.empty(shape, dtype=dtype)
+            ret = np.empty(shape, dtype=dtype)
 
         if dtype == 'datetime64':
-            return np.array(data, dtype='M8[ns]')
-        return data
-
+            ret = np.array(data, dtype='M8[ns]')
+        ret = data
+    
+    if transposed == True:
+        return ret.T
+    else:
+        return ret
+    
 def _unconvert_index(data, kind):
     if kind == 'datetime64':
         index = DatetimeIndex(data)