title: Pytorch, what are the gradient arguments
body: <p>I am reading through the documentation of PyTorch and found an example where they write </p>
  
  <pre><code>gradients = torch.FloatTensor([0.1, 1.0, 0.0001])
  y.backward(gradients)
  print(x.grad)
  </code></pre>
  
  <p>where x was an initial variable, from which y was constructed (a 3-vector). The question is, what are the 0.1, 1.0 and 0.0001 arguments of the gradients tensor ? The documentation is not very clear on that.</p>