title: Comparing pandas.Series for equality when they are in different orders
body: <p>Pandas automatically aligns data indices of Series objects before applying the binary operators such as addition and subtraction, but this is not done when checking for equality. Why is this, and how do I overcome it?</p>
  
  <p>Consider the following example:</p>
  
  <pre><code>In [15]: x = pd.Series(index=["A", "B", "C"], data=[1,2,3])
  
  In [16]: y = pd.Series(index=["C", "B", "A"], data=[3,2,1])
  
  In [17]: x
  Out[17]:
  A    1
  B    2
  C    3
  dtype: int64
  
  In [18]: y
  Out[18]:
  C    3
  B    2
  A    1
  dtype: int64
  
  In [19]: x==y
  Out[19]:
  A    False
  B     True
  C    False
  dtype: bool
  
  In [20]: x-y
  Out[20]:
  A    0
  B    0
  C    0
  dtype: int64
  </code></pre>
  
  <p>I am using pandas 0.12.0.</p>