title: numpy.argmax: how to get the index corresponding to the *last* occurrence, in case of multiple occurrences of the maximum values
body: <p>I have an array of numbers, and the maximum value might occurrence more than once. </p>
  
  <p>Is it possible to find the index of the last occurrence of the maximum value by using something like numpy.argmax?</p>
  
  <p>Or, even better, is it possible to get a list of indices of all the occurrences of the maximum value in the array?</p>