title: quiver3 returns vectors with incorrect length
body: <p>I have a set of vectors</p>
  <pre><code>t = [ -1    -1     0
         1    -1     0
         1     1     0
        -1     1     0 ]
  </code></pre>
  <p>those vectors form a square when plotted sequentially (head to tail)</p>
  <p>I am using the <code>quiver3</code> instruction to obtain a plot of those vectors as follows:</p>
  <pre><code>quiver3(starts(:,1), starts(:,2), starts(:,3), t(:,1), t(:,2), t(:,3))
  </code></pre>
  <p>I calculated &quot;starts&quot; by cumulative sums of the matrix t and got the following result</p>
  <pre><code>starts = [ 0     0     0
            -1    -1     0
             0    -2     0
             1    -1     0]
  </code></pre>
  <p>All the values makes perfect sense and would give a square if plotted manually, but <code>quiver3</code> returned the following plot</p>
  <p><img src="https://i.stack.imgur.com/pk0BW.jpg" alt="enter image description here" />
  <img src="https://i.stack.imgur.com/EWdvi.jpg" alt="enter image description here" /></p>
  <p>Why aren't the vectors' heads touching the tails? how can I fix that?</p>