BUG: tests pass now

Author: wesm

pandas/core/groupby.py

@@ -323,10 +323,17 @@ def _generator_factory(self):
 
 def _is_indexed_like(obj, other):
     if isinstance(obj, Series):
+        if not isinstance(other, Series):
+            return False
         return obj.index.equals(other.index)
     elif isinstance(obj, DataFrame):
+        if not isinstance(other, DataFrame):
+            return False
+
         return obj._indexed_same(other)
 
+    return False
+
 class Grouping(object):
 
     def __init__(self, index, grouper=None, name=None, level=None):
@@ -780,7 +787,7 @@ def _wrap_applied_output(self, keys, values, not_indexed_same=False):
                 columns = values[0].index
                 index = keys
             else:
-                stacked_values = np.vstack(values)
+                stacked_values = np.vstack(values).T
                 index = values[0].index
                 columns = keys
 

pandas/tests/test_sparse.py

@@ -310,7 +310,7 @@ def _compare_with_dense(sp):
             dense = sp.to_dense()
 
             def _compare(idx):
-                dense_result = dense.take(idx)
+                dense_result = dense.take(idx).values
                 sparse_result = sp.take(idx)
                 assert_almost_equal(dense_result, sparse_result)