title: Randperm columns of a matrix
body: <p>Hey i have a matrix A 3x3..</p>
  
  <pre><code>A= [1 2 3 4
      2 3 4 5
      3 4 5 6]
  </code></pre>
  
  <p>I want with randperm to generate a new matrix B where the columns will be shuflled..Anyone can help?</p>