 construct orthogonal rotation matrix 
</pre>

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<div class="subtitle">Examples</div>

<p>
Taking three arbitrary angles, we compute the rotation matrix
</p>

<pre class="matlab">
ang = [34 72 -143]*pi/180;
R = erot(ang)
</pre>

<pre class="mloutput">
R =
    0.1319   -0.6369    0.7595
    0.6008   -0.5581   -0.5724
    0.7885    0.5318    0.3090
</pre>

<p>
Now, feeding this rotation matrix into <code>eulang</code>, we get back the three 