title: What is the borrow parameter in Theano
body: <p>I see this following line of code:</p>
  
  <pre><code>n_train_batches = train_set_x.get_value(borrow=True).shape[0] / batch_size
  </code></pre>
  
  <p>In the above line, what is the borrow parameter exactly? What is the advantage of adding that there? FYI, train_set_x is basically a matrix that was generated using the theano.shared method.</p>