title: Octave signal package installation
body: <p>I'm on Ubuntu 16.04 and currently using Octave as a reciprocal to Matlab for signal processing. Everything was fine till I needed to use <code>medfilt1</code> function to get the median. Octave generated an error report saying that signal package is not installed on my system. After browsing a bit I found the command</p>
  
  <pre><code> sudo apt-get install octave-signal
  </code></pre>
  
  <p>I ran this command and it showed everything downloaded and installed perfectly. However, if I again run the octave script the error persists:</p>
  
  <blockquote>
    <p>warning: the 'medfilt1' function belongs to the signal package from Octave Forge
    which you have installed but not loaded.  To load the package, run 'pkg
    load signal' from the Octave prompt.</p>
    
    <p>Please read <a href="http://www.octave.org/missing.html" rel="noreferrer">http://www.octave.org/missing.html</a> to learn how you can
    contribute missing functionality.
    warning: called from
        <strong>unimplemented</strong> at line 524 column 5
        filter-practice.m at line 8 column 2
    error: 'medfilt1' undefined near line 8 column 3
    error: called from
        filter-practice.m at line 8 column 2</p>
  </blockquote>
  
  <p>Analyzing the error message I attempted to run <code>pkg load signal</code> but the terminal told me that there is no such command. </p>
  
  <blockquote>
    <p>command not found: pkg</p>
  </blockquote>
  
  <p>How can I get the signal package installed on my system?</p>