title: np.quantile with wrong calculation?
body: <p>Under certain settings, np.quantile makes mistakes in determining the correct quantile. Is this a bug?</p>
  
  <pre><code>x = np.array([374, 358, 341, 355, 342, 334, 353, 346, 355, 344,
                349, 330, 352, 328, 336, 359, 361, 345, 324, 386,
                334, 370, 349, 327, 342, 354, 361, 354, 377, 324])
  
  q = np.quantile(x, 0.25)
  
  print(q)
  
  print(len(x[x&lt;=q]) / len(x))
  
  print(len(x[x&gt;=q]) / len(x))
  </code></pre>
  
  <p>Output:</p>
  
  <pre><code>337.25
  
  0.26666666666666666
  
  0.7333333333333333
  </code></pre>
  
  <p>0.73 means that only 73% of values are larger or equal than the determined quantile; by definition it should be >= 75%</p>