title: Row and column labelling of matrixes in LaTeX
body: <p>How to add labels to the columns and rows (such as <code>a</code>, <code>b</code>, <code>c</code>, <code>d</code> and the like) which go above and to the left (both outside) of the matrix, but are obviously aligned with said columns and rows?</p>
  
  <p>An example matrix:</p>
  
  <pre><code>\[
  \begin{pmatrix}
  t   &amp; 1-t &amp;  -1 &amp;  0  &amp;  0  \\
  0   &amp;  t  &amp; 1-t &amp;  -1 &amp;  0  \\
  0   &amp;  0  &amp;  t  &amp; 1-t &amp;  -1 \\
  -1  &amp;  0  &amp;  0  &amp;  t  &amp; 1-t \\
  1-t &amp;  -1 &amp;  0  &amp;  0  &amp;  t
  \end{pmatrix}
  \]
  </code></pre>