</span>
        kf.xp = zeros(n , 1);
        <span class="comment">% Execution of the extended Kalman filter</span>
        kf = kalman(kf, dtg);
</pre>
<h2 id="15">OBSERVABILITY</h2>
<pre class="codeinput">        <span class="comment">% Number the observable states at current vor_dme time</span>
        ob(gdx) = rank(obsv(kf.F, kf.H));
</pre>
<h2 id="16">INS/vor_dme CORRECTIONS</h2>
<pre class="codeinput">        <span class="comment">% Quaternion correction</span>
        qua_skew = -skewm(qua(1:3));  