title: agreement how a Matrix (2D) is stored as JSON?
body: <p>Is there some agreement on how a Matrix should be stored as JSON from math software like Matlab/Octave/R?</p>
  
  <p>For example</p>
  
  <pre><code>a =
      1   2
      3   4
  </code></pre>
  
  <p>can be saved as (and it's my favourite because it's fortran order):</p>
  
  <pre><code>{"a":[[1,3],[2,4]]}
  </code></pre>
  
  <p>Another way (this is what <a href="https://github.com/fangq/jsonlab/" rel="nofollow noreferrer">jsonlab</a> would do):</p>
  
  <pre><code>{"a":[[1,2],[3,4]]}
  </code></pre>
  
  <p>But is there some agreement/common sense under JSON user?</p>