title: How to create an inequality constraint on the inner product of two columns in CVXPY?
body: <p>Suppose my constraint is the product of the first column and third column of the matrix variable is greater than one. How can I implement in CVXPY? Example:</p>
  
  <pre><code>w = Variable(4,3) 
  </code></pre>
  
  <p>In Matlab, my constraint would be:</p>
  
  <pre><code>w(:,1)'*w(:,3)&gt;1
  </code></pre>
  
  <p>How can I implement it in CVXPY? Or can we perform dot product under CVXPY? <code>numpy.dot</code> is not supported by CVXPY.</p>