title: Select specific rows of 2D PyTorch tensor
body: <p>Suppose I have a 2D tensor looking something like this: </p>
  
  <pre><code>[[44, 50, 1, 32],
  .
  .
  .
  [7, 13, 90, 83]]
  </code></pre>
  
  <p>and a list of  row indices that I want to select that looks something like this <code>[0, 34, 100, ..., 745]</code>. How can I go through and create a new tensor that contains only the rows whose indices are contained in the array?</p>