title: How can I retrieve a row by index value from a Pandas DataFrame?
body: <p>I have created a dataframe and set an index:</p>
  
  <pre><code>df = pd.DataFrame(np.random.randn(8, 4),columns=['A', 'B', 'C', 'D'])
  df = df.set_index('A')
  </code></pre>
  
  <p>The dataframe looks like this:</p>
  
  <pre><code>                  B         C         D
  A
   0.687263 -1.700568  0.140175  1.420394
  -0.212621 -0.700442 -0.041497 -1.034021
  -0.614214 -0.437313 -0.464493 -1.182492
  -0.885062  0.203892 -0.412400 -0.578346
  -1.222661  2.014908 -0.463674 -0.378910
   0.132472 -0.389512  0.623531 -0.788556
  -1.083620  1.167158 -0.558217 -0.222078
   1.066270 -0.215586 -0.884757 -0.878557
  </code></pre>
  
  <p>How do I get the value of B in the row for which <code>A</code> is <code>0.687263</code>?</p>
  
  <p>I've tried:</p>
  
  <pre><code>e = df.loc(0.687263)
  </code></pre>
  
  <p>This gives me a <code>LocIndexer</code> object, rather than the row I'd expect (also I'd like to specify that it should be a single row if possible):</p>
  
  <pre><code>&lt;pandas.core.indexing._LocIndexer object at 0x10385e210&gt;
  </code></pre>
  
  <p>And if I now try <code>e['B']</code> I get an error. </p>
  
  <p>How do I get the value of B?</p>