title: PHP count Multidimensional Array value
body: <p>Let say I have an array</p>
  
  <pre><code>[
    {0:1, 1:5, 3:null},
    {0:4, 1:null, 3:null},
    {0:null, 1:5, 3:5}
  ]
  </code></pre>
  
  <p>I want to count that so my expected output is</p>
  
  <pre><code>[{0:2, 1:2, 3:1}]
  </code></pre>
  
  <p>I do not have any idea how to archive that, please help.</p>