title: Creating Categorical Variables in Octave (implementing dummyvar)
body: <p>So within a data file that I would like to pass into an octave function, I have a categorical field, like this:</p>
  
  <pre><code>group =
  
  msie-7
  msie-8
  msie-7
  msie-8
  msie-9
  firefox-15
  chrome-21
  chrome-21
  firefox-15
  msie-7
  msie-8
  msie-9
  ..
  </code></pre>
  
  <p>I would like to turn this into a series of dummy variables (similar to the factor function in R). For some reason though, my installation of Octave does not recognize the <code>dummyvars</code> function.</p>
  
  <pre><code>octave-3.2.4.exe:16&gt; dummyvars(group)
  error: `dummyvars' undefined near line 16 column 1
  octave-3.2.4.exe:16&gt; dummyvar(group)
  error: `dummyvar' undefined near line 16 column 1
  </code></pre>
  
  <ol>
  <li>Any idea why this is the case?</li>
  <li>How would I go about writing a function to work around this? I have functions in octave designed for regularized logistic regression analysis, but this inability to handle categorical variables is a big set back. </li>
  </ol>