title: How to sum all the arrays inside a list of arrays?
body: <p>I am working with the confusion matrix. So for each loop I have an array (confusion matrix). As I am doing 10 loops, I end up with 10 arrays. I want to sum all of them. 
  So I decided that for each loop I am going to store the arrays inside a list --I do not know whether it is better to store them inside an array.</p>
  
  <p>And now I want to add each array which is inside the list. </p>
  
  <p>So If I have:</p>
  
  <pre><code>    5 0 0       1 1 0
      0 5 0       2 4 0
      0 0 5       2 0 5
  </code></pre>
  
  <p>The sum will be:</p>
  
  <pre><code>    6 1 0
      2 9 0 
      2 0 10
  </code></pre>
  
  <p>This is a picture of my confusion matrices and my list of arrays:
  <a href="https://i.stack.imgur.com/ZMFT0.png" rel="noreferrer"><img src="https://i.stack.imgur.com/ZMFT0.png" alt="enter image description here"></a></p>
  
  <p>This is my code: </p>
  
  <pre><code>   list_cm.sum(axis=0)
  </code></pre>