title: Scale training set by inverse standard deviation using python
body: <p>I am using python and have a training set of data that i need to 'subtract the mean and scale by inverse standard deviation'. Subtracting the mean would just be subtracting the mean from each value in each column i assume, but i have no idea what i am meant to do when it says to 'scale by inverse standard deviation'.</p>
  
  <p>I have googled it but nothing has come up in relation to python or neural networks so i'm not sure how to continue.</p>
  
  <p>Thanks</p>
  
  <p>EDIT: Would this be correct?</p>
  
  <pre><code>scaled_train =  (train - train_mean) / train_std_deviation
  </code></pre>