title: Is there a python t test for difference?
body: <p>Is there a t test in a python package where you can test for difference?
  If there is how do you use it?</p>
  
  <p>For example test two vectors:</p>
  
  <pre><code>a=np.random.randn(5, 7)
  b=np.random.randn(5, 7)
  </code></pre>
  
  <p>I have found the t test : ttest_ind in statsmodels. 
  However I would like to specify the difference to test for, this can not be passed into the ttest_ind function. Does anybody know another way to do this?</p>