title: How to make tridiagonal matrix in matlab?
body: <p>How I create matrix  below from vector [1 2 3 4 5]</p>
  
  <pre><code>1 0 0 0 0
  2 1 0 0 0
  3 2 1 0 0
  4 3 2 1 0
  5 4 3 2 1
  0 5 4 3 2
  0 0 5 4 3
  0 0 0 5 4
  0 0 0 0 5
  </code></pre>