title: Logsoftmax stability
body: <p>I know how to make softmax stable by adding to element -max _i x_i. This avoids overflow and underflow. 
  Now, taking log of this can cause underflow. log softmax(x) can evaluate to zero, leading to -infinity.</p>
  
  <p>I am not sure how to fix it. I know this is a common problem. I read several answers on it, which I didn't understand. But I am still confused on how to solve this problem.</p>
  
  <p>PS: If you provide a simple example, it would be awesome.</p>