title: How to find unknown operator A for two known vectors in MATLAB?
body: <p>Say I have a matrix <code>A</code> that has four symbolic values <code>a, b, c, d</code> and the rest are zero. The positions of the values are known:</p>
  
  <pre class="lang-matlab prettyprint-override"><code>sym a b c d
  A = [a b 0 0; c 0 0 0; 0 d 0 0; 0 0 0 0]
  </code></pre>
  
  <p>(Note, I randomly placed these symbols. The dimensions I'm dealing with are bigger than this.)</p>
  
  <p>Now say I have two vectors <code>x</code> and <code>y</code> that are known exactly. I want to find the values for <code>a, b, c, d</code> that take x to y. Specifically, I want to solve for all/any <code>A</code>'s in the equation <code>A*x = y</code> in MATLAB. How is this done?</p>